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1
Li, Zhi Xiang y Jing Zheng. "A Transmission Control System's Research for a Nursing Bed with Four Transmissions Driven by a Single Motor". Advanced Materials Research 443-444 (enero de 2012): 518–22. http://dx.doi.org/10.4028/www.scientific.net/amr.443-444.518.
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This paper introduces a kind of multi-function nursing bed control system which has won Chinese invention patent. This system takes AT89C51 as a core, uses a unique control mode for a single electrical machinery driven four transmissions, and adopts a modular control technology which respectively controls the movements of four lead screws through electrical machinery’s positive or negative rotation, and electromagnetic clutch’s connection or disconnection to decide the power transmission direction, so as to realize the different postures of the nursing bed, and meet the demands of patient care.
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Matyja, Tomasz y Bogusław Łazarz. "Simulation Studies of the Effect of Shaft's Nonlinear Flexural Stiffness Parameters for Critical States of Rotating Power Transmission Systems". Solid State Phenomena 236 (julio de 2015): 62–69. http://dx.doi.org/10.4028/www.scientific.net/ssp.236.62.
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The paper presents simulation studies, performed using Simulink, the impact of nonlinear flexural stiffness of shafts for critical speed range and amplitude of vibration. The tests were performed on the selected model of a rotating machine, consisting of a drive, two torsional vibration dampers, shaft with mounted on it two rigid rotors (discs), supported on a three self-aligning roller bearings and mechanical power receiver (brake). The machine startup and braking with crossing the critical states was simulated using specialized Simulink library, which was developed by authors for analysis of transient states in rotating machines and flexural-torsional couplings. In accordance with the concept of modeling adopted by the authors, rotating system is divided into inertial rigid elements (rotors, bearings, clutches, etc..) and compliance elements (parts of the shaft). The main component of the currently developed library is block modeling rigid rotor with 6 degrees of freedom and with the static and dynamic unbalance. By assumption the library is a modular, expandable and allows modeling the systems of any configuration. The goal of the simulation was to verify how nonlinear flexural stiffness of shaft influences the values of critical speeds and the level of flexural and torsional vibrations.
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Duan, Jian Rui, Jin Yao y Hua Li. "The Calculation Method of Lock-Up Clutch Friction Work". Applied Mechanics and Materials 475-476 (diciembre de 2013): 1375–81. http://dx.doi.org/10.4028/www.scientific.net/amm.475-476.1375.
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In order to calculate the friction work of lock-up clutch, which come from the lock-up process of hydraulic torque converter, this article established a simplified dynamic model of the engine and hydraulic torque converter , according to the route of power transmission and the rule of moment balance. And then the mathematical model of the lock-up process was deduced. This article reached a calculation method of lock-up clutch friction work by the mathematical model , and did some further simplified. Meanwhile, the lock-up process was simulated by Matlab/Simulink. By analyzing the simulatin resultthe computed result of machinery bookthe computed result of the improved method, the correctness of the improved method was verified.
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Rafea M. Abd El-Maksoud, Rafea M. Abd El-Maksoud. "Advanced Power Transmission System". journal of King Abdulaziz University Engineering Sciences 23, n.º 2 (22 de febrero de 2012): 191–207. http://dx.doi.org/10.4197/eng.23-2.10.
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Different researches are adopted to modify and enhance automatic transmission by every means. Whereas, torque converter that represents the most important component in such transmission suffers from some problems that are not completely solved. In this paper, power transmission system is herein introduced as a unique power transmission system that is not affected by torque converter problems. This power transmission operates with power splitting concept and is composed of conventional torque converter connected to planetary sets. Three clutches are used to shift the operating modes and unique positive displacement hydraulic couplings are utilized to regulate performance in power paths. Also, a modified model used to predict torque converter performance is utilized with planetary gear kinetics to assess the transmission performance. Moreover, the present system operates with high performance. Unlike the automatic transmission that operates in line, the present system operates with infinity number of operational bands for each engine speed.
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Li, Yan Min, Zhi Hua Liu, Dong Wang y Yong Zhang. "Analysis on the Shifting Performance of the Hydraulic System of a Transmission for Construction Machinery". Advanced Materials Research 201-203 (febrero de 2011): 2206–11. http://dx.doi.org/10.4028/www.scientific.net/amr.201-203.2206.
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The paper discusses the performance of a hydraulic system controlling the shifting action of a construction vehicle transmission. Based on the principle of the hydraulic system of the transmission, a simulation model of the hydraulic system is established using AMEsim software. The simulation results indicate that the double-step hydraulic cylinder structure has an advantage of a fast, smooth and reliable shifting. The shifting connecting and separating overlap time of two clutches can be controlled precisely by an electronic joystick. The fast response speed can be ensured because using screw-in cartridge valves acting as the directional valves. Some techniques of improving the shifting quality are obtained. There is a great reference for the construction vehicles’ transmission in the future.
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Sheu, Kuen Bao, Tsung Hua Hsu y Yuan Yong Hsu. "A Novel Parallel Hybrid Motorcycle Transmission". Materials Science Forum 505-507 (enero de 2006): 1021–26. http://dx.doi.org/10.4028/www.scientific.net/msf.505-507.1021.
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This paper presents a novel parallel hybrid transmission for motorcycles. This transmission incorporates a mechanical type rubber V-belt continuously variable transmission and chain drives to combine the power of the two power sources, an internal combustion engine and an electric motor. By using the mechanical type clutches used in the proposed transmission, it can provide a parallel hybrid that can be grouped into four modes of operation: electric motor mode, engine mode, engine/charging mode, and power mode. A design example is built and tested.
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Chen, De Min, Qing Ge Cai y Hong Zhang. "Simulation and Test Study of Multidisc Magneto-Rheological Fluid Clutch". Applied Mechanics and Materials 599-601 (agosto de 2014): 464–67. http://dx.doi.org/10.4028/www.scientific.net/amm.599-601.464.
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A Magneto-rheological Fluid Clutch (MRC for short) which has a novel and simple structure is designed; the research on the magnetic field distribution is based on the finite element simulation software which is named Ansoft; In order to test the work performance, the electronic torsion testing machine is used for the torque transmission capability and controllability test. The experimental results reveal that the MRC could meet the torque transmission demand of high power machine and response quickly and reliably.
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Hoodorozhkov, Sergey y Andrey Krasilnikov. "Digital twin of wheel tractor with automatic gearbox". E3S Web of Conferences 164 (2020): 03032. http://dx.doi.org/10.1051/e3sconf/202016403032.
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This article describes the digital twin of power drive unit (engine and transmission) of 8-ton class wheel tractor with automatic gearbox. Detailed mathematical model of considered tractor power drive unit - engine with 16-speed automatic gearbox and friction shift of stages under load without breaking the power flow is given. The theoretical methods of research are based on the use of the MATLab package. With the help of fundamental package units, models of gearbox physical components are created: friction clutches, gears, shafts with the required properties, engine mathematical model, as well as model of the transmission control system. The calculation methods of the gearbox dynamic processes going on in the gear shifts using friction clutches is proposed. A feature of the mathematical model is consideration of the resistive torque, the rate of rise of switched on clutches friction torque, both during switching to the higher and lower gears. Mathematic simulation of tractor power drive unit operation under load was performed. The results of the completed calculations are presented. The possibility of using this digital model to simulate tractor operation during its main work operations is shown.
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Liu, Jikai, Biao Ma, Heyan Li, Man Chen y Guoqiang Li. "Control strategy optimization for a dual-clutch transmission downshift with a single slipping clutch during the torque phase". Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 232, n.º 5 (10 de mayo de 2017): 651–66. http://dx.doi.org/10.1177/0954407017704783.
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During the torque phase, appropriate coordination between two clutches is of vital importance to the dual-clutch transmission so that a high-quality shift is achieved without clutch interaction and engine flare, because a poor-quality shift definitely extends the shift time and increases the friction work. Concerning this problem, two different power flow conditions during the torque phase are discussed in detail, after investigation of the dual-clutch transmission downshift process and the design of an H∞ robust controller for the inertia phase. The results obtained indicate that, if two clutches are slipping simultaneously during the torque phase, either power interruption or power circulation occurs. Thus, by optimizing the relationship between the two clutches, a novel control strategy is proposed for the dual-clutch transmission so that the downshift process is accomplished with only one slipping clutch, in order to obtain the highest system efficiency. The system model was established on the MATLAB/Simulink platform and used to study the variations in the torque and the speed output in response to different control strategies. The simulation results show that, with the smooth inertia phase guaranteed by the robust controller, the proposed control strategy not only can avoid power interruption or power circulation during the torque phase but also can shorten the shift time (from 1.1 s to 0.8 s) and reduce the jerk level (from 6.8 m/s3 to 5.7 m/s3) effectively, in comparison with the conventional control strategy. Finally, to validate the effectiveness of the proposed control strategy, bench tests on a dual-clutch transmission were carried out, and the test data obtained show good agreement with the simulation results.
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Rogkas, Nikolaos, Despoina Almpani, Georgios Vasileiou, Eustratios Tsolakis, Christos Vakouftsis, P. Zalimidis y Vasilios Spitas. "A comparative study on the effect of disks geometrical features on the drag torque of a wet friction clutch". MATEC Web of Conferences 317 (2020): 04001. http://dx.doi.org/10.1051/matecconf/202031704001.
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In recent years, the need for highly efficient automatic and semiautomatic powertrains has led to the wide use of wet friction clutches as power transmission systems. While wet friction clutches surpass their counterparts dry-friction clutches in the engagement process as they provide higher efficient torque and smoother torque and speed transmission, yet they fall behind in their disengaged state where the clutch acts as a power loss to the system due to the drag torque developed on the disks from fluid’s viscous shear stresses. Shear stresses are developed due to the relative speed difference of coaxial disks distanced at a prescribed axial clearance and rotating independently, yielding to a torsional Couette shear flow. This matter has been investigated thoroughly in the literature with experimental and numerical approaches for the case of flat disks admitting the complex flow pattern, which is augmented even more from the presence of geometrical features (grooves) on the surface of the disks. It becomes clear that the efficient calculation and understanding of drag torque can lead to its minimization and therefore to further establishing the use of wet clutches. In this work the effect of various disks geometrical features on the drag torque of a wet clutch is examined. The results are obtained via FEA (Finite Element Analysis) using the commercial software ANSYS.
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Hedman, A. "Transmission Analysis—Automatic Derivation of Relationships". Journal of Mechanical Design 115, n.º 4 (1 de diciembre de 1993): 1031–37. http://dx.doi.org/10.1115/1.2919252.
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A method for derivation of relationships for general mechanical transmission systems is given. It is adapted for computer-aided analysis and synthesis of the kinematics, loads, and power flows. Losses are included. All relationships are handled by a computer program. No manual dealing with equations is necessary. The user only describes the transmission systems: (1) The transmission units, e.g., gear transmissions, planetary gear trains, clutches and input shafts. (2) How the shafts of those units are connected. Then, the computer program formulates the relationships, and a computer algebra program performs algebraic eliminations. Symbolic, non-numerical, relationships between speeds and torques of two arbitrary shafts can be derived, e.g., the overall efficiency. Special algorithms handle the power flows in split-power transmissions. The method saves time and eliminates the risk for human errors.
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Li, Baogang, Dongye Sun, Minghui Hu, Xingyu Zhou, Junlong Liu y Dongyang Wang. "Coordinated control of gear shifting process with multiple clutches for power-shift transmission". Mechanism and Machine Theory 140 (octubre de 2019): 274–91. http://dx.doi.org/10.1016/j.mechmachtheory.2019.06.009.
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Zhong, Youkun. "Design and Analysis of Thermal Management System of Power Matching Transmission in Energy Machinery". International Journal of Heat and Technology 39, n.º 2 (30 de abril de 2021): 629–37. http://dx.doi.org/10.18280/ijht.390234.
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With the technical development of energy conservation and emission reduction technology, the internal structure of engineering machinery has become denser. The rising full-machine heat load that ensues challenges the effect of the cooling system. In the traditional thermal management system for the transmission in energy machinery, the cooling capacity does not fully match the load of each subsystem, and the thermal management components cannot adapt to the dynamic cooling demand of engineering machinery. To solve these problems, this paper designs and analyzes the thermal management system of power matching transmission in energy machinery. Firstly, the energy distribution among different components of engineering machinery, including, hydraulic system, transmission system, and cooling system, was described in each work section, and the dynamic matching method was detailed for hydraulic torque converter. Then, heat source engine, hydraulic torque converter, and hydraulic retarder were selected as the targets of thermal management for the power transmission system of loader. Next, the thermal management cycle was framed as a scheme in which the engine transmission system is independent with the cooling circulation system, and a heat transfer calculation model was constructed for loader transmission system. The proposed model was proved effective through experiments. The research results provide a reference for the thermal management of other subsystems of engineering machinery.
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Bi, De Xue, Hai Fei Long y Zhi Chao Sun. "A New Design Method of Dexterous Hand Based on Power Second Distribution". Applied Mechanics and Materials 236-237 (noviembre de 2012): 1316–20. http://dx.doi.org/10.4028/www.scientific.net/amm.236-237.1316.
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This paper presents a new design method of TUST dexterous hand. With cable based transmission scheme and implementation methods, and a new designed clutch device and finger cable-drive mechanism for second distribution of electrical power, the plan of using one motor to drive a robot hand with 21 Degrees of Freedom is fulfilled. Then the prototype is machined and manufactured, and the main design propose is verified.
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Han, Hyun-Woo, Jung-Su Han, Woo-Jin Chung, Ji-Tae Kim y Young-Jun Park. "Prediction of Synchronization Time for Tractor Power-Shift Transmission Using Multi-Body Dynamic Simulation". Transactions of the ASABE 64, n.º 5 (2021): 1483–98. http://dx.doi.org/10.13031/trans.14233.
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HighlightsPrediction of synchronization time was performed for a power-shift transmission.We derived an analytical equation for synchronization time and developed a multi-body dynamics model.Model results were compared with results of a power-shift test on a synchronizer.Reduced computation and design time was achieved for automatic transmission design.Abstract. Synchronization time determines the capacity of a shift actuator for an automatic transmission system. Existing approaches for measuring this time only consider one rotational inertia and therefore cannot be applied to the power-shift transmission (PST) of a tractor with wet multi-plate clutches on both sides of the synchronizer. This study aims to predict the PST synchronization time by considering time-varying axial forces as first-order functions and the equivalent rotational inertias of the hub and the gear. First, we derive an analytical equation for the synchronization time. We then develop a multi-body dynamics (MBD) model that includes the drag torque of the wet multi-plate clutches. The MBD model is composed of a synchronizer, a linkage, and an output shaft of a shift actuator as a rigid-body system. A power-shift test was performed on the synchronizer at two shift stages requiring the maximum shift force of the system. The torque of the shift actuator (the input of the shift system) and the angular displacement of the output shaft of the shift actuator (the output of the shift system) were measured. The results of the simulation model were then compared with those of the shift test. Compared with the test results, the simulation results were validated within 7.63% accuracy, based on the maximum value for the torque of the shift actuator. The proposed equation was validated within a maximum error range of 8.25%. The proposed equation did not consider drag torque of the wet multi-plate clutches because that torque is much smaller than the cone torque of the synchronizer in the target shift system. The proposed equation can reduce computation time and will enable more precise sizing of the synchronizer and shift actuator in the early design stages of automatic transmissions. Keywords: Multi-body dynamics, Power-shift transmission, Synchronization time, Synchronizer, Tractor transmission.
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AHMADIZADEH, P. y B. MASHADI. "OPTIMAL CONTROL OF THE EASIER MANAGEMENT DUAL-MODE POWER-SPLIT TRANSMISSION". Latin American Applied Research - An international journal 47, n.º 3 (31 de julio de 2017): 113–18. http://dx.doi.org/10.52292/j.laar.2017.310.
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This paper deals with the optimal control strategy design of the easier management (EM) dual-mode power-split device (PSD) in hybrid electric vehicles (HEV). The EM mechanism provides two modes of operation for the HEV based on the clutches performance. One mode is the input split mode and the other is the compound split mode. Dynamic programming (DP) method is used to find the optimal control strategy including the mode switching and the power split between the power sources while providing the charge sustaining condition. Simulation results show significant improvements of the fuel consumption in comparison to the Toyota Hybrid System (THS), which is a well-known industrialized PSD, and in comparison to the rule-based methods. Keywords − − ,, , I
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Chen, Guo Jin, Ting Ting Liu, Jing Ni, Ming Xu y Huo Qing Feng. "Research on Adaptive Power Control System of Working Machinery". Applied Mechanics and Materials 278-280 (enero de 2013): 1504–9. http://dx.doi.org/10.4028/www.scientific.net/amm.278-280.1504.
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The load changes of working machinery in the running process will certainly result in poor matches in the characteristics of the transmission system. For the issue, this paper studies the adaptive power control model and algorithm. The adaptive power control system is developed using the adaptive power control technology based on the load identification, and is applied in the full AC electric forklift and the CNC band sawing machine. The variable frequency system and intelligent control method based on the integration of the load characteristic recognition and control proposed in this paper, adaptively adjust the parameters of the PID controller according to the load characteristic parameters identified real-timely for the transmission system of the working machinery, so as to achieve the best performance matches, the highest effectiveness and lowest energy consumption of the entire transmission system.
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Billah, MM, MS Hossain, MR Islam y MA Rahman. "Selection of V-Belt for Power Transmission in Agricultural Machinery". Progressive Agriculture 19, n.º 2 (11 de noviembre de 2013): 187–94. http://dx.doi.org/10.3329/pa.v19i2.16961.
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The solution of a v-belt design problem depends upon many data tables, figures, equations and sequence of calculations. To solve such a problem a computer program is developed which facilitates the design procedure by fast computation with less drudgery and more accuracy. Computed result shows the diameter of smaller and larger sheave, center distance, belt length, belt number, required number of belt, belt cross-section, as output after calculation. The computer-generated output by using this program is found more accurate and efficient than the conventional calculation method.DOI: http://dx.doi.org/10.3329/pa.v19i2.16961 Progress. Agric. 19(2): 187 - 194, 2008
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Salamandra, Konstantin. "Static analysis and parameters synthesis of planetary-layshaft transmissions with three power flows". MATEC Web of Conferences 224 (2018): 02040. http://dx.doi.org/10.1051/matecconf/201822402040.
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The increase in the number of transmission ratios in the vehicles gearboxes leads to an increase in the number of mechanisms used and their complication. One way to obtain simple designs of multi-speed transmissions with smaller number of gears, clutches, brakes and synchronizers is to use combinations of planetary differential gears and gears with fixed axes (planetary-layshaft transmissions). The article presents a static analysis of a planetary-layshaft transmissions with three parallel power flows for obtaining the dependencies between the gear ratios of the internal mechanisms and the speed ratios of the transmission. A technique for determination the gear ratios of the internal mechanisms for providing a close to a given series of transmission ratios is described.
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Krykhtin, Yu I. y V. I. Karlov. "HIGH-PERFORMANCE METHOD OF PRODUCTION OF POWDER FRICTIONAL PRODUCTS ON FE-BASIS WITH HIGH TECHNOLOGICAL AND OPERATIONAL PROPERTIES". IZVESTIA VOLGOGRAD STATE TECHNICAL UNIVERSITY, n.º 2(249) (25 de febrero de 2021): 20–26. http://dx.doi.org/10.35211/1990-5297-2021-2-249-20-26.
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Physical and technological bases of DHP-PFM method for production of dry friction powder friction articles on Fe-base with high technological and operational indices for a wide range of practical use have been developed. The DHP-PFM method is that the dynamic hot pressing (DHP) provides production of the new powder frictional materials (PFM) through an underlayer from carbonyl iron between frictional material and a basis (framework) with electroplated nickel coating. Friction lining compaction is made of charge of ФМК-79 type and has high hardness and low porosity. Processes of the choice of composition of furnace charge, formation of structure and properties of new powder frictional materials on Fe-to a basis are investigated. The method is characterized by high productivity, energy saving, simplified technology and provides the possibility to use existing technological equipment for making structural powder products. Method of DHP-PFM manufacturing of dry friction powder friction linings can be used for manufacturing of friction units of transmissions of light track machines with high specific power. The friction material received by this method from furnace charge of FMK-79 type can be used as unified for such frictional units as the main friction clutch, an onboard friction clutch, tape and disk brakes.
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Niu, B. y N. Olhoff. "Minimization of vibration power transmission from rotating machinery to a flexible supporting plate". International Journal of Structural Stability and Dynamics 14, n.º 03 (16 de febrero de 2014): 1350068. http://dx.doi.org/10.1142/s0219455413500685.
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This paper deals with the problem of optimum design of a foundation for rotating machinery with a view to minimize vibration transmission from a machine source to its supporting structure. The problem of analysis and optimization of the installation systems of machinery has been extensively researched on the assumption of a rigid supporting structure. The design based on a rigid supporting structure model is reasonable for the installation of machinery in many real engineering situations. However, this rigid support based model may not be appropriate for the problem studied herein where the machinery is to be installed on a relatively flexible supporting plate. Thus, a generalized mathematical model of mobility power flow is developed in this paper, with a rotating machine as vibration source, resilient mounts as isolator, and a flexible supporting plate as receiver. The objective of minimizing vibration transmission is realized by optimization of stiffness coefficients of resilient mounts with a constraint on the vibration level of the machine. The design objective is chosen as the minimization of the power flow transmitted to the flexible supporting plate through the resilient mounts at the excitation frequency of the machinery. Both a single excitation frequency and a range of excitation frequencies are considered. A gradient-based mathematical programing method is selected for its advantage of efficiently solving the current type of optimization problem with multiple mounts and multi-degree-of-freedom vibration transmission. The sensitivities of the objective and the constraint functions with respect to the design variables are derived analytically. The design and performance of the optimized machinery foundation is illustrated and discussed using several numerical examples. The optimized mounting system is suitable for the installation case of a rotating machine with a low or medium service speed on a flexible supporting plate structure.
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Deng, Tao, Fen Bin Hu y Dong Ye Sun. "Study on Torque Control Strategy of Dual Clutch Transmission during Shifting". Applied Mechanics and Materials 121-126 (octubre de 2011): 3541–45. http://dx.doi.org/10.4028/www.scientific.net/amm.121-126.3541.
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Based on the analysis of Dual clutch transmission (DCT) working principle, the shift kinetics model is established, and the power switching rule between two clutches during upshift and downshift is established by analyzing the torque transmission relationship of vehicle driveline system during shifting, then shift process is tested on actual vehicle with Matlab/Simulink software. Comparing the two different kinds of downshift processes, and illuminating the effect on engine control by various downshift control rules, the downshift process is optimized.
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Liu, Guo Qiang, Wei Sun, De Min Chen y Xiao Lin Guo. "Pressure Measurement System Design and Controlling Study on the Double-Clutch Automatic Transmission". Advanced Materials Research 490-495 (marzo de 2012): 946–50. http://dx.doi.org/10.4028/www.scientific.net/amr.490-495.946.
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Dual-clutch automatic transmission with two clutches alternate way to achieve work uninterrupted power shift, showing the precise control of the clutch in the dual clutch automatic transmission is extremely important, From that point the text, the design of a converter based on AD7731 dual clutch automatic transmission pressure measurement system, the analysis in detail the system design and the corresponding interface circuit, the test results show that the pressure measurement system design can be very good to meet the needs of the clutch pressure measurement system
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Hoodorozhkov, S. I. y A. А. Krasilnikov. "Numerical simulation of dynamic processes in transmission of vehicle". Izvestia MGTU MAMI 1, n.º 1 (2021): 38–45. http://dx.doi.org/10.31992/2074-0530-2021-47-1-38-45.
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The article considers the issues of digital modeling of dynamic processes in the transmissions of vehicles. The purpose of this research was to develop an algorithm for numerical mathematical modeling of dynamic processes in the transmissions of transport vehicles using modern digital software packages. The method includes a systematic approach to the study of dynamic processes during switching, based on modeling the operation of the gearbox together with the internal com-bustion engine (taking into account its dynamic, speed and load characteristics). The order of appli-cation of the MATLab – Simulink, Simscape software for numerical simulation of dynamic pro-cesses is considered. Using the fundamental blocks of these applications, models of physical com-ponents are created: the internal combustion engine, friction clutches, gearboxes, elastic shafts, damping devices, and tractor power transmission control systems. A digital model of the tractor transmission is created, its design scheme is given, and the initial characteristics are set. It was used to simulate dynamic processes in the tractor gearbox. The main attention in this paper is paid to the application of the proposed method for calculating the dynamic processes in the gearbox during gear changes under load with forward and reverse switching, including the simultaneous use of several friction clutches.
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Mou, Liu Chen y Guang Fu Yin. "Power Train-Vehicle Modeling to Simulate Shifting Transients of Off-Highway Vehicles". Advanced Materials Research 44-46 (junio de 2008): 415–20. http://dx.doi.org/10.4028/www.scientific.net/amr.44-46.415.
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Analytic modeling and analog computer simulation techniques are presented to determine the power train transient responses excited by clutch-actuated gear shifts. A method to describe the dynamics of a transmission arrangement having several clutches and interconnected planetary gear sets is considered in detail. Simulation model testing is directed toward optimizing system design parameters and evaluating power train component capability and vehicle shift-feel. Data reduction techniques applied to model responses of torque and speed will yield appropriate spectrums representative of simulated work cycle.
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Jia, Zhizhou y Pingkang Li. "Nonlinear Dynamics of a Power-Split Transmission Unit with a Planetary Gear Train and Selectable One-Way Clutches". Complexity 2020 (30 de marzo de 2020): 1–16. http://dx.doi.org/10.1155/2020/8729365.
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A Planetary Gear Train (PGT) can be used in series-parallel transmission to redistribute powers. Selectable one-way clutches (SOWCs), compared with traditional friction clutches, can simplify controls and diversify patterns especially for hybrid transmissions. In this paper, a nonlinear torsional model of a power-split PGT coupled with three SOWCs is proposed. Piecewise nonlinearities of SOWCs as well as clearance, time-varying mesh stiffness, and synthetic transmission error of the PGT are considered. With a specified group of comprehensive evaluation indices, influences of piecewise nonlinearities of SOWCs are explored. Simulation results show that the piecewise nonlinearities of SOWCs can diminish collision range and reduce resonances of the PGT. Further research studies on parameter configurations of each SOWC reveal that of the three SOWCs, stiffness and radius of the SOWC connected to the sun gear of the PGT are dominant factors. Large stiffness and effective radius of the SOWC render the PGT fall into chaos on lower meshing frequencies; however, enormous impact vibrations occur to the SOWC if it gets too soft. Additionally, the increase of the damping ratio of the SOWC connected to sun gear can distinctly reduce the vibration and maximum dynamic load of the system on the entire working range.
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Mockensturm, Eric M. y Raghavan Balaji. "Piece-Wise Linear Dynamic Systems With One-Way Clutches". Journal of Vibration and Acoustics 127, n.º 5 (6 de diciembre de 2004): 475–82. http://dx.doi.org/10.1115/1.1897737.
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One-way clutches and clutch bearings are being used in a wide variety of dynamic systems. Motivated by their recent use as ratchets in piezoelectric actuators and decoupling devices in serpentine belt drives, a method of analysis of systems containing one-way clutches is presented. Two simple systems are analyzed. The goal of the first is the power transmission which would be of concern in an actuator. The goal of the second is decoupling large inertia elements to reduce loads in an oscillating system, the objective of the clutch in a serpentine belt drive. Results show how system parameters can be tuned to meet the desired performance of these piece-wise linear systems.
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Habermehl, Christian, Georg Jacobs, Stephan Neumann y Kevin Weißenfels. "Influence of Drivetrain Hybridization on Transmission Lifetime". Applied Sciences 10, n.º 20 (12 de octubre de 2020): 7086. http://dx.doi.org/10.3390/app10207086.
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Parallel hybrid drivetrains for passenger cars have additional electric drives compared to conventional drivetrains. In the event of vehicle deceleration, the electric drives are operated as generators, thus recovering kinetic energy through regeneration. If these drives are positioned upstream of the transmission input, regeneration power must be transferred by the transmission. This creates additional loads on the individual machine elements, which has a negative effect on the transmission lifetime. This paper investigates the influence of hybridization in terms of regeneration on the lifetime of bearings as highly critical elements in a dual clutch transmission. The vehicle simulation model employed in this study consists of an internal combustion engine, an electric motor, a mechanical drivetrain and the vehicle body, as well as a driver and a simple operating strategy. In this model, a detailed transmission model including its controls is embedded to determine its component loads. The resulting load spectra are used in a methodical approach to calculate the bearing lifetime of the transmission. The results show that the additional regenerative power flow reduces the bearing lifetime so that additional loads must be taken into account in the development and operation of transmission systems.
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Phan, Tai Tan. "MODELLING AND SIMULATION OF THE AUTOMOBILE DYNAMICS MOVEMENT USING MATLAB SIMULINK SOFTWARE". Scientific Journal of Tra Vinh University 1, n.º 1 (13 de junio de 2019): 94–103. http://dx.doi.org/10.35382/18594816.1.1.2019.94.
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As the car moving, the power of the engine is transmitted to the active wheel through the transmission system. In such a transmission, the power is lost due to friction in the powertrain and the power of the active wheel will be less than the output of the engine. The transmission system consists of components such as clutches, transmissions, propeller shaft, active bridge, differential and active wheels. During the working process, each of these parts is affected by the individual factors that reduce their performance. This article is to analyze the structure, function, task and modeling of the vehicle transmission system components, building the dynamics movement model of the transmission system according to D’Alambert principle, in which the dynamics of the wheel and the axle as well as the rigidity of the powertrain and chassis are mentioned. The Matlab Simulink software is used to simulate the automobile drive system. Thereby, the factors affecting the operation of the transmission system are analysed and evaluated in order to clarify the law of motion, and propose solutions that improve the quality of the transmission system on automobile.
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Wang, Junyan, Changgao Xia, Xin Fan y Junyu Cai. "Research on Transmission Characteristics of Hydromechanical Continuously Variable Transmission of Tractor". Mathematical Problems in Engineering 2020 (12 de agosto de 2020): 1–14. http://dx.doi.org/10.1155/2020/6978329.
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This paper proposes a new transmission scheme of hydromechanical continuously variable transmission (HMCVT) for tractors. The HMCVT has 4 working ranges in each of the front and rear directions. The speed characteristic and the torque characteristic of HMCVT are theoretically derived. On the basis of HMCVT power flow direction, the Крейнeс formula is used to calculate the transmission efficiency. Then, the image analysis method is used to study the influence of parameters on the transmission efficiency of HMCVT, and the main influencing factors are found. The results of theoretical derivation demonstrate that, by coordinating control of the HST displacement ratio and the engagement conditions of shifting clutches, the stepless speed regulation of HMCVT at the tractor speed of 0–50 km/h can be realized. The proposed HMCVT has the ability to continuously transmit and change torque over all working ranges. The overall transmission efficiency of HMCVT is at a high level. To verify the theoretical derivation, Amesim simulation software is used for the modeling and simulation of HMCVT. The simulation results are consistent with the theoretical analysis results. Therefore, the HMCVT proposed in this paper has the advantages of compact structure and high transmission efficiency, and it is suitable for matching tractors.
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Shapovalov, Vladimir, Petr Shcherbak, Pavel Kharlamov, Tatiana Sajamova y Denis Ryabysh. "Improving the energy efficiency of power transmissions of a rolling stock on the basis of dynamic anisotropy of frictional contact". E3S Web of Conferences 104 (2019): 01002. http://dx.doi.org/10.1051/e3sconf/201910401002.
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The analysis showed the following tendencies of development and energy efficiency of designs of gearboxes for track machines: provision of a maximum level of efficiency, removal of rupture of a stream of the passed capacity, provision of a high level of reliability, decrease of power input on gearbox work, provision of convenience, simplicity of service and steering, engine braking maintenance, and also maintenance of a relatively low cost. The above-mentioned tasks are performed by including clutch pinion gears with the built in frictional amplifier elements in an automatic gearbox, and also during the effect of dynamic anisotropy of frictional bonds. Besides a torque transfer, the clutch gear carries out a safety clutch function. That means that there is sliding at a high rotational power. Factor of strengthening of the given link is Кstr → ∞ due to occurence of dynamic anisotropy of frictional bonds. Physical and mechanical characteristics of contacting surfaces are formed in the course of dynamic interaction of roughnesses in friction units at modes of dry and boundary friction. Essential-nonlinear friction processes, interconnected with dynamic processes on the contact area, define values of target characteristics of frictional system. They can fluctuate in a very wide range. The friction factor fmp for the same friction units at preservation of constant conditions and friction parameters can vary from zero to infinity that is an essence of dynamic anisotropy of frictional bonds.
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Lou, Xi Yin. "Research of Track-Type Full Feeding Combine Harvester Walking Design Scheme Based on Hydraulic Close System". Applied Mechanics and Materials 697 (noviembre de 2014): 187–89. http://dx.doi.org/10.4028/www.scientific.net/amm.697.187.
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Hydraulic technology is one of the key techniques of modern transmission and control. Closed type hydraulic power transmission system is weight ratio, fast action, easy to realize the advantages of flexible stepless speed regulation, flexible power transmission. In this paper, the closed hydraulic system of double bidirectional variable hydraulic pump and the bidirectional quantitative motor, the drive system for crawler type machinery, advantages, in the walking system design process can reasonable calculation and power matching, reasonable selection of power components, the universal value of engineering application.
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Demidov, N. N., A. A. Krasilnikov y S. I. Hoodorozhkov. "TRACTOR GEARBOX: RESEARCH OF SHIFTING GEARS’ PROCESSES". Russian Automobile and Highway Industry Journal 17, n.º 1 (5 de marzo de 2020): 58–71. http://dx.doi.org/10.26518/2071-7296-2020-17-1-58-71.
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Introduction. The process of shifting gears under load is one of the most complex types of dynamic process in the transmissions of transport, road and construction vehicles. Currently, the existing calculation methods do not fully reflect the features of the engine and automated gearbox interaction by switching stages under load using more than two friction clutches at the same time. The paper discusses the method of calculating the dynamic characteristics of the gearbox with the simultaneous use of both two and four friction clutches by shifting gears under load with forward and reverse switching. The authors present the results of the dynamic characteristics of the theoretical study of the automated gearbox with frictional stages’ switching under load and without breaking the power flow.Materials and methods. The main method was based on a system approach to the dynamic processes study and on the modeling of the gearbox operation together with the internal combustion engine. The authors took into account the regulatory, speed and load engine characteristics, resistive torque variation, rate of pressure rise in clutches by shifting to higher and lower gears. The paper performed theoretical modeling of processes using the MATLab package and the Simulink application. Using the main blocks of this application, the authors created models of physical components: an internal combustion engine, friction clutches, gear reducers, elastic shafts, damping devices and tractor power transmission control systems.Results. As a result, the authors obtained calculated data of the dynamic processes, variations in speed and rotational torque on the gearbox shafts; the load on the engine by shifting gears at different values of the start and finish time in switching on and off the gearbox friction controls. The paper presented the relevant graphs of the processes.Discussion and conclusions. The developed method of calculating the dynamic characteristics of the gearbox allows simulating workflows by shifting to higher and lower gears. This method takes into account both the parameters of the gearbox design and of the control actions: the rate of switching on the friction clutches; the time intervals of overlapping the “on and off” clutches. Therefore, in relation to the considered gearbox, the authors determine the values of the optimal time control commands of the friction by shifting.Financial transparency: the authors have no financial interest in the presented materials or methods. There is no conflict of interest.
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Chen, Yan-song, I.-Ming Chen y Tyng Liu. "A design approach for multi-configuration hybrid transmission mechanisms". Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 234, n.º 12 (20 de junio de 2020): 2744–58. http://dx.doi.org/10.1177/0954407020924981.
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Several hybrid architectures have been widely used in hybrid electric vehicles. For example, power-split architecture brings seamless operation, while parallel architecture makes the internal combustion engine directly drive the wheel. To combine the advantages of various architectures, this study aims to develop a design approach to create a transmission mechanism that has multiple configurations and uses these configurations to achieve several hybrid architectures. First, this study standardized hybrid transmission mechanisms using the Function Power Graph; this powerful and intuitive tool inspired several elements and an element layout for the new mechanisms. Then, several configurations with up to five elements were enumerated and organized into the databases. Next, the mechanisms with multiple configurations and a limited number of clutching units (clutches or brakes) were evaluated, 10 of which were identified as the best group that provided five parallel configurations, two 2-motor electric vehicle configurations, and a power-split configuration. At the end of this paper, a novel hybrid transmission mechanism was developed as a demonstration. It provides higher power and torque at the output but there is no need to use the larger internal combustion engine or motor-generators. This mechanism also enables the internal combustion engine to drive in overdrive parallel architectures to avoid the loss in energy conversion when the power-split architecture is not required. As a result, after a designer specifies the desired hybrid configurations, follows the procedure, and uses the configuration databases built in this study, a novel hybrid transmission mechanism will be created.
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Zhang, Ming Zhu y Zhi Li Zhou. "Modeling and Control Simulation for the Multi-Range Hydro-Mechanical CVT". Key Engineering Materials 621 (agosto de 2014): 462–69. http://dx.doi.org/10.4028/www.scientific.net/kem.621.462.
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To develop the control system of multi-range hydro-mechanical continuously variable transmission (HMCVT), a model of a multi-range HMCVT is built using the principle of dynamics. According to the characteristic of power split, HMCVT is separated as axes set, variable displacement pump-motor system, clutch set. With wheel tractor as application instance, the whole model of vehicle power train is made, which includes the engine, HMCVT, running system and control system. Based on the theory of Finite State Machine, an automatic control method of speed change and range shift is present, which employs the throttle value, engine speed, range number and transmission ratio as the control parameters. The dynamic characteristic of automatic speed changing and ranges shifting is simulated. The result indicates that the model can correctly represent the dynamic characteristic of HMCVT, the engine can run at the optimal working point, the multi-range HMCVT can shift range steadily and change transmission ratio continuously when the load changes, the circularly shift range is avoided. The model can be used conveniently for the analysis of vehicle dynamic performance and the research of multi-range HMCVT control method.
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Wang, Cheng. "High power density design for planetary gear transmission system". Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 233, n.º 16 (17 de mayo de 2019): 5647–58. http://dx.doi.org/10.1177/0954406219850212.
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Planetary gear transmission system has been widely used in the field of aerospace equipment, automobiles, ships, etc. High power density design is an important development direction for transmission machinery, but there is a lack of systematic and deepening research in planetary gear transmission system field. Taken the most widely used 2K–H-type planetary gear transmission system as research object, a design method of high power density considering volume and efficiency is put forward. First, the transmission efficiency model of 2K–H-type planetary gear transmission system is built on the basis of calculation of single gear pair meshing efficiency instead of the look-up table method. Second, the volume model of 2K–H-type planetary gear transmission system is built according to the structure of gear. Finally, the smallest volume and the minimum power loss of 2K–H-type planetary gear transmission system are the target of optimization, and the linear-weighted combination method is used to construct target function. Taken a 2K–H-type planetary gear reducer in some machine tool as an example, the optimization is carried out. The results show that the power loss of optimized system is reduced by 11.42%, and the volume of system is reduced by 25.2%.
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Wu, Yi-Chang y Zi-Heng Sun. "Design and Analysis of a Novel Speed-Changing Wheel Hub with an Integrated Electric Motor for Electric Bicycles". Mathematical Problems in Engineering 2013 (2013): 1–8. http://dx.doi.org/10.1155/2013/369504.
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The aim of this paper is to present an innovative electromechanical device which integrates a brushless DC (BLDC) hub motor with a speed-changing wheel hub stored on the rear wheel of an electric bicycle. It combines a power source and a speed-changing mechanism to simultaneously provide functions of power generation and transmission for electric bicycles. As part of the proposed integrated device, the wheel hub consists of a basic planetary gear train providing three forward speeds including a low-speed gear, a direct drive, and a high-speed gear. Each gear is manually controlled by the shift control sleeve to selectively engage or disengage four pawl-and-ratchet clutches based on its clutching sequence table. The number of gear teeth of each gear element of the wheel hub is synthesized. The BLDC hub motor is an exterior-rotor-type permanent-magnet synchronous motor. Two-dimensional finite-element analysis (FEA) software is employed to facilitate the motor design and performance analysis. An analysis of the power transmission path at each gear is provided to verify the validity of the proposed design. The results of this work are beneficial to the embodiment, design, and development of novel electromechanical devices for the power and transmission systems of electric bicycles.
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Dai, Lu, Tie Jun Yang, Xu Hu y Han Bing Ke. "Investigation on Power Transmission for the Isolation System Mounting on Plate-Shell Coupled Structure". Applied Mechanics and Materials 716-717 (diciembre de 2014): 631–34. http://dx.doi.org/10.4028/www.scientific.net/amm.716-717.631.
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An approach of combining the rigid body theory and improved Fourier series method is proposed to model the single-stage isolation system based on an elastic plate-shell coupled structure, and the isolation performance is investigated. Considering the practical problems of the machinery system design in the field of marine engineering, the influences of various structural parameters on the isolation performance for the isolation system is implemented. The numerical simulation results are given and discussed.
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Kim, Jungyun, F. C. Park, Yeongil Park y Mishima Shizuo. "Design and Analysis of a Spherical Continuously Variable Transmission". Journal of Mechanical Design 124, n.º 1 (1 de agosto de 2000): 21–29. http://dx.doi.org/10.1115/1.1436487.
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In this article we propose the design of a novel continuously variable transmission, the spherical continuously variable transmission (S-CVT). The S-CVT consists of a sphere, input and output discs, and variators. The rotating input and output discs are connected to the power source and output shafts, respectively, while the sphere is situated between the input and output discs. The transmission ratio is controlled by adjusting the location of the contact point between the variators and the sphere, which in turn controls the axis of rotation of the sphere. The S-CVT can smoothly transit between the forward, neutral, and reverse states without any brakes or clutches, and its compact and simple design and its relatively simple control make it particularly effective for mechanical systems in which excessively large torques are not required (e.g., mobile robots, household appliances, small-scale machining centers). We describe the operating principles behind the S-CVT, including a kinematic and dynamic analysis. Simulations and experiments with a constructed prototype are conducted to assess the performance of the S-CVT, including a study of its energy efficiency vis-a´-vis reduction gears.
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Kátai, László, Péter Szendrő y Péter Gárdonyi. "The power transmission stability and efficiency of V-belts". Progress in Agricultural Engineering Sciences 12, n.º 1 (diciembre de 2016): 25–49. http://dx.doi.org/10.1556/446.12.2016.2.
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The V-belt drive is a rather popular, widely used form of power transmission in agricultural and food industry engineering. At the same time, its stability, the lifetime of V-belt is influenced by several environmental factors, namely in the food industry by the contamination affecting the belt sides, the ambient temperature, humidity and the occasionally aggressive (acidic, alkaline air, air saturated with gases, etc.) medium. In the case of agricultural machinery, the vibration caused by uncertainly oriented pulleys with bearing in different plate structures (often being shaken in the fields) as well as alignment adjustment inaccuracies jeopardize the reliability of the parameters of the drive. Furthermore, the efficiency is determined by several factors together: the slippage occurring during drive transmission, the hysteresis loss resulting from the external and internal friction occurring with the belt entering and exiting the pulley. Experimental equipment and calculation methods were developed to determine the dynamics of temperature increase generated by the belt and pulley relationship. The temperature generated in the V-belt was measured as a function of pretension, pulley diameter and bending frequency. The so-called damping factor characterizing the contact with the pulley (the external friction when entering and exiting the groove) and the hysteresis loss (inner friction) are also determined. On the basis of the damping factor (ζ ≈ 400 Ns/m2) of the V-belt involved in the experiments the other losses (Poth) occurring from the pulley—V-belt contact and internal friction may be estimated. The drive parameters may be optimized with the mathematical model describing the effect of the pulley diameter and belt frequency on the increase in temperature. A standardized calculation method as well as design factors valid for the properly adjusted drive and normal operating conditions determined through empirical and laboratory experiments are used for the sizing of V-belt drives. The lifetime of V-belt drives designed in this way, used in extreme conditions typical of agricultural machinery will not be appropriate and will not provide clear, predictable information for maintenance planning. In such cases the results of our own many lifetime tests conducted in the given circumstances can be safely relied on. The agricultural harvesting machines are large plate-body self-propelled structures on which most of the power supply of the (threshing, cleaning, moving, etc.) machine units handling the crop is realized via belt drives. The distance and angular displacement of the axes involved in the drive can vary within wide limits. The misalignment and angular displacement of the pulleys can be the result of installation instability — due to the plate structure — and the deformation of the plate structure occurring during the operation as well. V-belt drives operate satisfactorily under such conditions as well, however these faults are unfavourable in terms of belt lifetime and result in the reduction of drive efficiency. A further aim of our research is to examine through experiments the lifetime and efficiency of V-belts used in agricultural machines as a function of drive adjustment errors. According to the results of the measurements of the geometrical adjustment errors of V-belt drives performed in the field, the pulleys of agricultural equipment are not always positioned in the medium plane of the drive. In our experiments these data served as independent variables. Figure 1 shows the arrangement of a V-belt drive in a grain harvester with the laser pulley alignment measuring instrument installed as an accessory. In the case of many machine types in 80% of the tested drives three times the permissible error was measured, and because of off-road use, due to dynamic load these errors further increased as a result of the frame deformation. The results of both the belt bending testing and the geometrical adjustment testing of the drive offer great help in the design of belt drives. At the same time they can be the source of lifetime and efficiency forecasts.
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Tsai, Ming-Fong, Yen-Ching Chu, Min-Hao Li y Lien-Wu Chen. "Smart Machinery Monitoring System with Reduced Information Transmission and Fault Prediction Methods Using Industrial Internet of Things". Mathematics 9, n.º 1 (22 de diciembre de 2020): 3. http://dx.doi.org/10.3390/math9010003.
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A monitoring system for smart machinery has been considered to be one of the most important goals in recent enterprises. This monitoring system will encounter huge difficulties, such as more data uploaded by smart machines, and the available internet bandwidth will influence the transmission speed of data and the reliability of the equipment monitoring platform. This paper proposes reducing the periodical information that has been uploaded to the monitoring platform by setting an upload event through the traits of production data from machines. The proposed methods reduce bandwidth and power consumption. The monitoring information is reconstructed by the proposed methods, so history data will not reduce storage in the cloud server database. In order to reduce the halt time caused by machine error, the proposed system uses machine-learning technology to model the operating status of machinery for fault prediction. In the experimental results, the smart machinery monitoring system using the Industrial Internet of Things reduces the volume of information uploaded by 54.57% and obtains a 98% prediction accuracy.
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Mao, Kun Li. "Research on Even-Loading Mechanism of Multi-Planetary Gear Transmission". Advanced Materials Research 834-836 (octubre de 2013): 1476–79. http://dx.doi.org/10.4028/www.scientific.net/amr.834-836.1476.
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Multi-planetary gear transmission is usually used in construction equipment, metallurgical machinery and wind-driven generator. Driving mechanism of heavy-duty equipment without even-loading system is badly loading, resulting in great impact force and severe vibration. To study characteristic of power dividing, multi-planetary gear transmission without any even-loading mechanism and that with flexible pin even-loading mechanism were simulated in commercial gear drive design software and dynamics analysis software. The simulation results are shown in this paper and conclusions are drawn useful for design and manufacture of heavy-duty multi-planetary gear transmission.
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Ho, Thanh-Tho y Sheng-Jye Hwang. "Configuration Synthesis of Novel Hybrid Transmission Systems Using a Combination of a Ravigneaux Gear Train and a Simple Planetary Gear Train". Energies 13, n.º 9 (7 de mayo de 2020): 2333. http://dx.doi.org/10.3390/en13092333.
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Thirty-two novel hybrid transmissions consisting of a Ravigneaux gear train and a single planetary gear train are synthesized using a creative design methodology based on graph-theory and the lever analogy method. The design process commences by identifying an existing transmission configuration which meets all of the design requirements. The chosen design is then used to synthesize all possible mechanism permutations which satisfy the design constraints. The feasible mechanisms which satisfy both the design requirements and the design constraints are converted into analogous levers. The levers which fail to provide the required operation modes of the hybrid transmission are eliminated and the remaining levers are assigned brakes and clutches in order to realize the final designs. The responsiveness of the new hybrid transmissions and the feasibility of the proposed design methodology are confirmed by analyzing the power flow and kinematics of one of the designs in all of the operation modes.
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Bin, Wei, He yongyong, Wang Wei y Luo jianbin. "Simulation and experiment of viscous torque for disengaged wet clutches of tracked vehicle". Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 233, n.º 4 (19 de julio de 2018): 593–604. http://dx.doi.org/10.1177/1350650118788143.
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In order to predict the viscous drag loss for tracked vehicles, the drag torque of the friction pair with different grooves was investigated in this paper. The traditional computation method is difficult to adapt for the new kinds of friction plates with complex grooves. A numerical method with the help of CFD models is adopted to simulate the fluid flow status in the grooves and the drag torque was obtained by the accumulation of the discrete viscous force. The simulation results implied that the plates with different kinds grooves were provided with various characteristics of viscous torque and these characteristics could be affected by the rotation direction for the plate with spiral grooves, which are proved in experiment. Meanwhile, it was also found that the two kinds of plates with double arc or spiral grooves, which have different sensitive parameters in drag dissipation, have to perform accurate flow control and clearance design respectively. The simulations and experiments showed that the ‘positive spiral grooves’ friction plates had minimum drag torque in regular heavy-duty conditions. It can be used in transmission system with requirements of limited space and high mobility, which can lead to better heat dissipation and less power loss.
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Guo, Xiaofan y Andrea Vacca. "Advanced Design and Optimal Sizing of Hydrostatic Transmission Systems". Actuators 10, n.º 9 (21 de septiembre de 2021): 243. http://dx.doi.org/10.3390/act10090243.
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This paper presents a novel method for designing and sizing high-efficient hydrostatic transmissions (HTs) for heavy duty propulsion applications such as agricultural and construction machinery. The proposed method consists in providing cost effective HT architectures that maximizes efficiency at the most frequent operating conditions of the transmission, as opposed to the traditional HT design methods based on the most demanding requirements of the system. The sizing method is based on a genetic optimization algorithm for calculating the optimal displacement of the main units of the HT to maximizes the efficiency in the most frequent operating conditions of the vehicle. A simulation model for HTs is built in MATLAB/Simulink® environment to test three different circuit alternatives for basic HTs. Considering a particular 250 kW heavy-duty application for which drive cycle data were available, this study shows great improvement in energy efficiency (14%) and power saving (20.1%) at frequent operating conditions while still achieving the corner power condition.
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Gao, You Shan, Zhi Song, Ai Hong Wang y Ze Kun Jin. "Dynamic Simulation for Rolling Impact Compaction Machine". Advanced Materials Research 430-432 (enero de 2012): 1610–13. http://dx.doi.org/10.4028/www.scientific.net/amr.430-432.1610.
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Through established the simulation model for the engine and the traction host powertrain of rolling impact compaction machine, Simulated the working load with time history with the simulation parameters of rolling impact compaction machine. The simulation accuracy was verified by compared between the test speed and the simulation speed. The speed, turbine torque, torque converter efficiency, torque converter, gear ratios, fuel consumption, engine power, torque are dynamic changes follow with the alternating load and slope load so as to adapt to the dynamic drag torque fluctuations. Traction host power must be equipped with a full host transmission of the internal combustion engine. Driveline should be hydraulic transmission fluid or hydraulic machinery.
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Kim, Yeon-Soo, Wan-Soo Kim, Md Abu Ayub Siddique, Seung-Yun Baek, Seung-Min Baek, Su-Hwan Cheon, Sang-Dae Lee et al. "Power Transmission Efficiency Analysis of 42 kW Power Agricultural Tractor According to Tillage Depth during Moldboard Plowing". Agronomy 10, n.º 9 (26 de agosto de 2020): 1263. http://dx.doi.org/10.3390/agronomy10091263.
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In order to optimize tractor design and optimize efficiency during tillage operation, it is essential to verify the impact through field tests on factors affecting the tractor load. The objectives of this study were to investigate the effect of tillage depth on power transmission efficiency of 42 kW power agricultural tractor during moldboard plowing. A load measurement system and a tillage depth measurement system were configured for field tests. To analyze the effect of tillage depth on power transmission efficiency and fuel consumption, the data measured in the three-repeated field test were classified according to tillage depth. As the tillage depth increased from 11 cm at the top of the hardpan to 23 cm at the deepest, the required power of the engine increased by approximately 13% from 35.48 kW to 40.11 kW, and the power transmission efficiency also increased significantly from 66% to 95%. Among them, the power transmission efficiency of the rear axle was significantly increased from 38% to 59%, which was the most affected. As the tillage depth increased, the overall power requirement is greatly increased due to the resulting workload, but the fuel consumption and the specific fuel consumption are reduced because the engine speed of the tractor is reduced. As the tillage depth increased from 11 cm to 23 cm, the fuel consumption rate was rather reduced by 13.5% as the engine rotational speed decreased 11.3% due to the increase work load of tractor. In addition, the specific fuel consumption decreased from 302.44 g/kWh to 236.93 g/kWh, showing a fuel consumption saving of up to 21.7% during moldboard plow. In addition, as the tillage depth increased, the ratio of the value excluding the mechanical and hydraulic power requirements has significantly decreased from 34% to 5% as the power transmission efficiency increases. This study considers the soil properties according to the soil depth, as well as the power transmission efficiency and fuel consumption rate. The research results can provide useful information for research on power transmission efficiency and selection of an appropriate power source of agricultural tractor according to tillage depth during moldboard plowing and are expected to be used in various ways as basic studies of digital farming research in agricultural machinery.
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Ayaki, Yukihiro, Shinya Uemachi, Takeshi Ishibashi y Yoshiaki Shirai. "Trinocular Vision System using Local Disparity Histogram for Detection of Heavy Machinery Approaching to Power Transmission Lines". IEEJ Transactions on Electronics, Information and Systems 117, n.º 10 (1997): 1418–24. http://dx.doi.org/10.1541/ieejeiss1987.117.10_1418.
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Stockinger, U., D. Groetsch, F. Reiner, K. Voelkel, H. Pflaum y K. Stahl. "Friction behavior of innovative carbon friction linings for wet multi-plate clutches". Forschung im Ingenieurwesen 85, n.º 1 (21 de enero de 2021): 115–27. http://dx.doi.org/10.1007/s10010-020-00436-9.
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AbstractThe torque transfer capability as well as long-term endurance are essential for wet multi-plate clutches. The quality of the torque transmission process largely depends on the tribological system consisting of friction pairing, lubricant and applied loads. The requirements on friction linings in wet multi-plate clutches increase continuously due to stricter CO2 reduction regulations and the demand of higher power densities.There is a lack of published data and information about the friction behavior of modern Carbon friction linings in wet multi-plate clutch applications, although these friction materials have successfully proven their performance capabilities over the last two decades in synchronizers. Therefore, this article presents results from experimental studies on the friction behavior of innovative Carbon friction linings carried out on a component test rig. Friction screening tests were performed with Carbon-fiber reinforced plastic (CFRP) and Carbon-fiber reinforced Carbon (C/C) linings in brake and constant slip operation. Furthermore, our research included long-term tests with different lubricants (engine/marine/tractor oil).Results show that modern Carbon friction linings can offer advantages over other materials. In the friction screening (brake and constant slip operations) and long-term tests, the torque transfer capability of both friction linings is very stable, even at high specific loads—sliding velocities near 30 m/s and axial pressures of 2.5 MPa. Influences of sliding velocity, pressure and lubricant on the friction performance are presented. Furthermore, the gradient of the Coefficient of Friction (CoF) curve usually decreases at the end of the engagement to enable good control and shift comfort.
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Hoodorozhkov, Sergey I., Andrey A. Krasilnikov y Matvey S. Gubachev. "Optimisation of an Algorithm for Automatic Control of Transmission in a Wheeled Tractor". International Journal of Automotive and Mechanical Engineering 18, n.º 3 (21 de septiembre de 2021): 9051–60. http://dx.doi.org/10.15282/ijame.18.3.2021.17.0694.
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The paper considers a digital model of a wheeled agricultural tractor, as well as algorithms for automatic control of the engine and transmission. Simulation of the working conditions was performed in MATLAB and its applications, Simulink, Sim-scape. The tractor model is based on a systemic approach and includes such subsystems as the engine, transmission, undercarriage, hook load, and control actions from the operator, as well as functions of logic and optimisation for gear shifting. With the help of fundamental blocks of the Matlab package, models of tractor physical components are created. The fundamental blocks of the package serve to model the physical components of the tractor: engine, transmission control system, the transmission that includes friction clutches, gears, shafts ties with the necessary characteristics. Simulation of the working processes of a tractor unit is performed with optimisation of the laws of engine and transmission control according to the criterion of fuel efficiency and maximum power usage. The control system parameters were optimised in the transport mode, as well as in the maximum power mode in the traction range. As an illustration of the use of this analysis method, a solution to the problem of optimisation of an agricultural wheeled tractor operating modes is given. The results of this mathematical simulation are presented in this paper. Parameters of tractor operation control algorithm, which provide minimum fuel consumption in tractor operating cycles, are given. The research results showed the effectiveness of the proposed algorithms and the digital model. The presented digital model allows to debug the operating tractor control algorithms and offers an engineering practice for optimising automatic control of the agricultural tractor engine and transmission.