Journal articles: 'Cylinder offset'

1

Zhang, Hai Yan, He Ping Hou, Jun Feng Si, and Xiao Yu Chen. "Parameter Study of Offset Press Cylinder Based on Sliding Friction." Advanced Materials Research 174 (December 2010): 299–302. http://dx.doi.org/10.4028/www.scientific.net/amr.174.299.

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In the contact area of offset, a relative slide occurs between the surface of plate cylinder and blanket cylinder, which changes the print image and influences the printing quality. The relative slide in the cylinders’ rolling process is investigated, and the determination rule of cylinders’ geometric parameters of offset press is proposed. The results show that the relative slide is minimization under the condition that the compression of elastic cylinder radius is 0.2 times bigger than that of rigid cylinder radius, and the deformation of print image and dot gain both are minimization. The results provide theoretical direction for accurate determination of cylinder radius of offset press.

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Igo, Naoki, and Kiyoshi Hoshino. "Variable offset pressure controller for air cylinder actuator." Abstracts of the international conference on advanced mechatronics : toward evolutionary fusion of IT and mechatronics : ICAM 2010.5 (2010): 135–40. http://dx.doi.org/10.1299/jsmeicam.2010.5.135.

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3

Guzzomi, A. L., D. C. Hesterman, and B. J. Stone. "Variable inertia effects of an engine including piston friction and a crank or gudgeon pin offset." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 222, no. 3 (March 1, 2008): 397–414. http://dx.doi.org/10.1243/09544070jauto590.

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In order to obtain greater accuracy in simulation, more sophisticated models are often required. When it comes to the torsional vibration of reciprocating mechanisms the effect of inertia variation is very important. It has been shown that the inclusion of this variation increases model accuracy for both single-cylinder and multi-cylinder engine torsional vibration predictions. Recent work by the present authors has revealed that piston-to-cylinder friction may modify an engine's ‘apparent’ inertia function. Kinematic analysis also shows that the piston side force and the dynamic piston-to-cylinder friction are interdependent. This has implications for engine vibration modelling. Most modern engines employ a gudgeon pin offset, and there is a growing interest in pursuing large crank offsets; hence, the effect of these on inertia variation is also of interest. This paper presents the derivation of the inertia function for a single engine mechanism, including both piston-to-cylinder friction and crank or gudgeon pin offset, and investigates the effect of each through predictions. The effect of crank offset on the variable inertia function is also verified by experiment.

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Guo, Jun Zhong, Jun Ping Yang, and Tian Tian Cai. "Rigid-Flexible Coupled Modeling and Simulation Analysis of Printing Cylinder Based on ANSYS." Advanced Materials Research 308-310 (August 2011): 2418–21. http://dx.doi.org/10.4028/www.scientific.net/amr.308-310.2418.

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In order to analyze the influence on the printing graphics from the deformation of the printing cylinders and blankets, in this paper, offset printing unit was as the research object, the three-dimensional assembly model of printing cylinders was established by using SolidWorks , the model was imported into finite element software ANSYS, by using ANSYS nonlinear contact calculated functionality, the face-to-face contact of impression surface between plate cylinder and blanket cylinder, blanket cylinder and impression cylinder were established, the stress and strain distribution of blanket were obtained, and the elongation value of circumferential and radial direction of blanket were got, the dot enlargement value was received by simulation analysis.

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Maheandera Prabu, Paulraj, Mahadevan Sivasubramanian, P. Rajesh Kanna, M. Uthayakumar, and K. P. Padmanaban. "Numerical Investigation of Forced Convection Heat Transfer from Offset Square Cylinders Placed in a Three Dimensional Confined Channel." Applied Mechanics and Materials 813-814 (November 2015): 729–35. http://dx.doi.org/10.4028/www.scientific.net/amm.813-814.729.

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Abstract-Flow over two offset square cylinders in a confined channel is simulated for different Reynoldsnumber to reveal the forced convection heat transfer from the heated square cylinders to the ambientfluid. The bottom of the cylinder is maintained at constant temperature. The distance between thecylinder in normal direction as well as transverse direction are fixed as 2d and the blockage ratio is fixedas 0.167. Heat transfer from the cylinders to the ambient fluid as well as conducted within solid wallthrough conjugate interface boundary investigated in connection with Reynolds number are reportedfor both steady and periodic flow. Simulation is carried out for Reynolds number varies from 10 to100 for the fluid as air with Prandtl number as 0.71. The isotherm contours, local Nusselt number andaverage Nusselt number are reported for various Reynolds number. The stagnation zone results higherNusselt number than remaining walls and rear wall results lowest Nusselt number. The downstreamcylinder results higher Nusselt number than the upstream cylinder. The top and bottom surfaceNusselt number from upstream and downstream cylinder are not analogous to single cylinder placed ina channel.

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Šalvienė, Eglė, Nikolaj Šešok, and Igor Iljin. "DAMPING TRANSVERSAL VIBRATIONS OF THE OFFSET CYLINDER OF THE OFFSET PRESS / RULONINĖS OFSETINĖS MAŠINOS OFSETINIO CILINDRO SKERSINIŲ VIRPESIŲ SLOPINIMAS." Mokslas - Lietuvos ateitis 3, no. 6 (January 3, 2012): 8–11. http://dx.doi.org/10.3846/mla.2011.101.

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Investigation into the influence of a dynamic vibration damper on the intensity of the absolute forced transversal vibrations of the blanket cylinder of the web printing offset press was performed. The analytical and numerical examination of the dynamic model of the cylinder was done. The obtained results have disclosed that the application of the damper decreases the intensity of printing cylinder vibrations. Santrauka Analiziniu ir skaitmeniniu būdu ištirtas dinaminio virpesių slopintuvo efektyvumas slopinant priverstinius periodinius ofsetinio spausdinimo įrenginio ofsetinio cilindro skersinius virpesius, bloginančius atspaudų kokybę. Atliktas ofsetinio cilindro ir virpesių slopintuvo modeliavimas „Matlab“ programa. Sudarytos „Simulink“ diagramos. Pateiktos amplitudinės dažninės charakteristikos. Parodyta, kad naudojant virpesių slopintuvus galima efektyviai mažinti spausdinimo įrenginio cilindrų skersinius virpesius.

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Li, P., T. Shen, and D. Liu. "Idle speed performance improvement via torque balancing control in ignition-event scale for SI engines with multi-cylinders." International Journal of Engine Research 13, no. 1 (October 24, 2011): 65–76. http://dx.doi.org/10.1177/1468087411405415.

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Imbalance in torque generation leads to engine speed fluctuation. To improve the idle engine speed performance, the torque balancing control problem is addressed in this paper for multi-cylinder SI engines. To evaluate cylinder-to-cylinder imbalance, the average torque in ignition-event scale is introduced as controlled output, which enables a feedback control to be performed without measurement of instantaneous torque, and the individual spark advances are chosen as control inputs. A linear discrete time model with single input and single output is proposed to represent the dynamics of the imbalance, where a sequentially switching function is introduced to describe the spark advance signals delivered to each cylinder and the differences in torque generation caused by the individual cylinder characteristics are equivalently modelled as unknown offset in the inputs. An estimation algorithm with the proof of convergence is presented to provide on-line estimation of the unknown offset under the passivity assumption of the system. Furthermore, a feedback control law which combines the unknown offset estimation and the model predictive control is proposed. Finally, the unknown offset estimation and the feedback control approach are validated based on the experimental results carried out on a six-cylinder gasoline engine test bench.

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8

Wu, Shu Qin, Yi Ming Wang, Ji Fei Cai, and Shao Hua Zhang. "Research on the Methods of the Testing on the Value of the Cylinder's Axial Bounce of the Press." Advanced Materials Research 174 (December 2010): 273–76. http://dx.doi.org/10.4028/www.scientific.net/amr.174.273.

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Printing cylinder driven by helical gear is the basic requirements of the modern printing press. Helical gear transmission necessarily produces component force in axial. It brings about a small displacement in axial to the cylinder, that is, axial bounce. The axial placement is too small or too large during the printing process, which both will have harmful effects on printed matter. At the same time, the axial playing of the cylinder is one of the important performance standards to determine printing press. The modern high-speed printing press has a higher requirement on mechanic properties and axial bounce. We tested on the cylinders of press and analyzed on the placement of the cylinders in order to effectively master and control the displacement in axial in the case of the printing press running with high-speed. We chose a four-color offset press as the test objects and reasonably selected measurement points on the cylinder shaft end face. We collected vibration signals of the blanket cylinders, impress cylinders and transfer cylinders. Then obtain the placement in axial of the cylinders with quadrature method. Analysis shows that the higher the printing speed, the larger the placement of the same type cylinder in axial is, which shows that the placement of the cylinders in axial has something to do with the printing speed. At the same speed, the blanket cylinder have a larger placement in axial than impress cylinder and transfer cylinder. Which shows that the placement of the cylinders in axial has connection to the cylinder assembly structure. Test data accord well with the actual structure and assembling condition, which can be considered as the theoretical basis to control the placement of cylinder in axial.

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9

Geng, Ainong, Kuihua Geng, Wengui Su, Hongdong Yu, and Xinmo Li. "Influence of Cylinder Offset on the Operation Characteristics of an Oil-Free Lubricated Wobble-reciprocating Compressor." Journal of Advanced Manufacturing Systems 15, no. 02 (April 27, 2016): 57–67. http://dx.doi.org/10.1142/s0219686716500062.

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This work introduced the structural characteristic and working principle of cylinder offset oil-free lubricated wobble-reciprocating compressor. A mathematical model of crank-link mechanism was setup. The influence of cylinder offset to side clearance, side pressure and friction power were discussed. It revealed that when the offset applied on suction stroke side, the peak value of side pressure in suction stroke was relatively low in comparison to that of the compression stroke. Low friction loss was hereby achieved; meanwhile the system’s sealability was deteriorated, due to the larger backlash between piston and cylinder during the compression process. Reverse trend was found when the offset moved to compression stroke side. The side pressure in suction stroke and the friction power increased, with the decrease of side pressure of compression process and the improvement of sealability.

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10

Griffith, Martin D., David Lo Jacono, John Sheridan, and Justin S. Leontini. "Flow-induced vibration of two cylinders in tandem and staggered arrangements." Journal of Fluid Mechanics 833 (November 2, 2017): 98–130. http://dx.doi.org/10.1017/jfm.2017.673.

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A numerical study of the flow-induced vibration of two elastically mounted cylinders in tandem and staggered arrangements at Reynolds number $Re=200$ is presented. The cylinder centres are set at a streamwise distance of 1.5 cylinder diameters, placing the rear cylinder in the near-wake region of the front cylinder for the tandem arrangement. The cross-stream or lateral offset is varied between 0 and 5 cylinder diameters. The two cylinders are identical, with the same elastic mounting, and constrained to oscillate only in the cross-flow direction. The variation of flow behaviours is examined for static cylinders and for elastic mountings of a range of spring stiffnesses, or reduced velocity. At least seven major modes of flow response are identified, delineated by whether the oscillation is effectively symmetric, and the strength of the influence of the flow through the gap between the two cylinders. Submodes of these are also identified based on whether or not the flow remains periodic. More subtle temporal behaviours, such as period doubling, quasi-periodicity and chaos, are also identified and mapped. Across all of these regimes, the amplitudes of vibration and the magnitude of the fluid forces are quantified. The modes identified span the parameter space between two important limiting cases: two static bodies at varying lateral offset; and two elastically mounted bodies in a tandem configuration at varying spring stiffnesses. Some similarity in the response of extremely stiff or static bodies and extremely slack bodies is shown. This is explained by the fact that the slack bodies are free to move to an equilibrium position and stop, effectively becoming a static system. However, the most complex behaviour appears between these limits, when the bodies are in reasonably close proximity, and the natural structural frequency is close to the vortex shedding frequency of a single cylinder. This appears to be driven by the interplay between a series of time scales, including the vortex formation time, the advection time across the gap between the cylinders and the oscillation period of both bodies. This points out an important difference between this multi-body system and the classic single-cylinder vortex-induced vibration: two bodies in close proximity will not oscillate in a synchronised, periodic manner when their natural structural frequencies are close to the nominal vortex shedding frequency of a single cylinder.

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11

Wang, Fang, and Hong Chen. "Design and Research on the Clutch Mechanism in Modern Offset Printing Machine." Advanced Materials Research 694-697 (May 2013): 128–32. http://dx.doi.org/10.4028/www.scientific.net/amr.694-697.128.

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The clutch mechanism is the important part of printing machine. At present, cam connecting rod type mechanical clutch mechanism has been used by most of the domestic offset printing machine and its mechanical structure is very complex and its reliability is very poor. So a new type of pneumatic clutch mechanism is designed to meet its technological requirements. For the new mechanism, the motion law of the blanket cylinder can be calculated in the pressing process by complex number vector method and the finite element model has been established, natural frequency, maximum amplitude and mode of vibration of the cylinder can be calculated based on Block Lanczos method. The analysis results show that the relationship between the cylinders is flexible impact at the pressing instant, positioning is accurate, stable and reliable, which meets flexible design requirements. Thus it is important significance to improve design level and the product quality of the domestic printing machine and shorten the gap with foreign advanced printing machine.

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12

Jin, Lin, Yan Li, Xiao Zhang, and Miao Liu. "Calculation Method on the Cooling Roller of Waterless Offset Press." Applied Mechanics and Materials 312 (February 2013): 196–99. http://dx.doi.org/10.4028/www.scientific.net/amm.312.196.

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In order to control the temperature of the ink, a cooling roller is used to cool down the temperature of the blanket cylinder. The calculation of the heat transfer on cooling roller is divided into two parts: One part is the exchange heat with the air through the cooling roller and the blanket cylinder, the other part is the heat conduction of the cooling roller and the blanket cylinder on the contact area. The heat conduction on the contact area is divided into the thermal conductivity generated by the friction and the heat conduction from blanket to the cooling roller.

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13

Yang, Jun Ping, Jun Zhong Guo, and X. Wang. "Analysis of Imapct of Plate Cylinder Deformation on the Graphic Quality." Advanced Materials Research 215 (March 2011): 332–35. http://dx.doi.org/10.4028/www.scientific.net/amr.215.332.

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Plate cylinder is the core component of the offset printing unit to complete the image transfer. The plate cylinder’s deformation will occur under pressure, resulting in the image’s deformation on the plate and the low printing quality. In this article, the three-dimensional digital model of plate, packing and cylinder are established by using solidworks software, they are assembled as a whole, the whole is imported into ANSYS finite element analysis software. The shaft of both sides of the cylinder are fixed, and the contact relations between plate, packing and cylinder body are defined, the pressure are load on the area with 5mm width on the surface of the plate cylinder. After solving, the flexural deformation of plate, packing and cylinder are obtained, through analyzing the axial and radial deformation of the plate, the graphic’s elongation which transferred from plate to blanket are received, consequently, an important basis of researching the image expansion will be provided.

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14

Liu, Lin Lin, Zai Rong Feng, and Chang Xing Wang. "Performance Research and Structure Optimize on Printing Cylinder Based on Finite Element Contact Analysis." Advanced Materials Research 174 (December 2010): 323–26. http://dx.doi.org/10.4028/www.scientific.net/amr.174.323.

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This paper concerns printing cylinders of offset press. In addition to research mechanism of the printing pressure, the paper employs finite element analysis and distance-anti-calculating to simulate the status of contacted contacting-cylinders. Deflection curves in axial and circumferential and the 3D model on deflection of cylinder are get. The result shows that in printing course, under the influence of gravity and printing pressure, the flexural deformation of cylinder is caused in the axial direction. besides, while printing pressure is applied to circumferential different position of printing cylinder, because of complex sectional construction，circumferential deformation is also inconsistent, so printing pressure is distributed asymmetrically that printing pressure is not only no-uniform in axial, but also wave-like periods in circumferential. The paper optimizes cylinder structure and proposes a new cylinder with pterygoid stiffeners of heterogeneous distribution. Simulation results show that the circumferential flexural curve of the optimized cylinder is obviously smooth than the original one, and the flexural distortion of the circumferential location point corresponding decreases, which indicates the anti-bending stiffness of optimized cylinder is enhanced as well as the flexural deformation is reduced, and the value of the different circumferential position’s printing pressure tends to be uniform. The maldistribution of the circumferential position’s printing pressure is improved effectively, which contributed to the improvement of printing quality.

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15

Lu, Yiyun, and Qiaohong Dang. "Magnetic Forces Investigation of Bulk HTS over Permanent Magnetic Guideway under Different Lateral Offset with 3D-Model Numerical Method." Advances in Materials Science and Engineering 2012 (2012): 1–6. http://dx.doi.org/10.1155/2012/640497.

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Magnetic forces of a cylinder shape bulk high-temperature superconductor (HTS) over a permanent magnet guideway (PMG) are studied mathematically. One cylindrical bulk HTS with a diameter of 30 mm and 15 mm in height is used. Two types of PMG are employed for external magnetic fields consideration. The relationship of magnetic forces of bulk HTS under different lateral offsets over PMG is studied with 3D-model finite element method (FEM). The calculation results show that the maximum magnetic levitation force of bulk HTS over PMG is tightly related to the applied magnetic field distribution. For the symmetrical PMG, the maximum magnetic levitation force decreases linearly with the increase of lateral offset of the bulk sample. For the Halbach PMG, when lateral offset changes from 0 mm to 25 mm, the maximum magnetic levitation force increases with the increase of lateral offset of the bulk HTS. When the lateral offset exceeds the center of the Halbach by 25 mm, the maximum levitation force decreases rapidly with the increase of the lateral offset of the bulk sample.

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GOTO, Masanori, Tatsuya UEDA, Takuji KOKUFU, Akihiro KIRI, and Norio ITO. "709 Effect of Cylinder-Offset on V-type Engine." Proceedings of Conference of Hokuriku-Shinetsu Branch 2007.44 (2007): 277–78. http://dx.doi.org/10.1299/jsmehs.2007.44.277.

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Guzzomi, A. L., D. C. Hesterman, and B. J. Stone. "Some Effects of Piston Friction and Crank or Gudgeon Pin Offset on Crankshaft Torsional Vibration." Journal of Ship Research 54, no. 01 (March 1, 2010): 41–52. http://dx.doi.org/10.5957/jsr.2010.54.1.41.

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The varying inertia associated with reciprocating mechanisms leads to nonlinear frequency coupling between rotational speed and an engine system's average torsional natural frequencies. This coupling can cause secondary resonance problems. Recent work by the authors has shown that piston-to-cylinder friction and gudgeon pin or crank offset can modify coupling behavior. These effects can be demonstrated by analysis of an engine's receptance function and through time simulations. This paper presents the derivation of a single-cylinder engine receptance in the presence of piston-to-cylinder friction. Simulations are then used to investigate some of the effects of piston-to-cylinder friction, offset, and excitation phase on the frequency content of the crankshaft velocity. Simulations indicate that nonlinear coupling is affected by these variables, which has implications for secondary resonance detection and prevention. The most significant finding is that stronger coupling behavior can occur when piston-to-cylinder lubrication breaks down.

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Liu, Qing Gang, Xi Qi Yu, Pei Ying Peng, and Yan Shu Guo. "Stress Analysis of Opening and Offset Nozzle on a Cylinder." Advanced Materials Research 614-615 (December 2012): 560–63. http://dx.doi.org/10.4028/www.scientific.net/amr.614-615.560.

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FEA(Finite Element Analysis) has been used in the stress analysis of two geometry sizes of opening and offset nozzle, corresponding standards has been included, and the results show that the strength of the cylinder is fit for safety requirement. The stress analysis also shows that the stress distribution principles are not dependent to the sizes of the opening, but closely to the positions. At the same time the magnitude of stress is relative to the size of the opening and the nozzle. So, stress analysis should be conducted to every offset opening and nozzle to ensure the safety of the cylinder.

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Zheng, Xin. "Model Analysis of Offset Cylinder Based on Finite Element Method." Applied Mechanics and Materials 312 (February 2013): 16–20. http://dx.doi.org/10.4028/www.scientific.net/amm.312.16.

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According to structural characteristics of blanket cylinder in the three-point suspended independent and dependent impression mechanism in offset, the 3D solid finite element model was established using ANSYS under hypothetical conditions by finite element model method. The intial five order model and the corresponding critical speed is gotten by the Block Lanczos characteristic value method. The calculation result shows that the maximum offset speed is less than first-order model critical speed, resonance can be avoided to meet printing quality requirements. The method is of highly significant in verifying reliability of blanket cylinder structure, forecasting response characteristic in certain circumstances in order to avoiding resonance and noise which cause mechanical defect.

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20

Tunestål, Per. "Model Based TDC Offset Estimation from Motored Cylinder Pressure Data." IFAC Proceedings Volumes 42, no. 26 (2009): 241–47. http://dx.doi.org/10.3182/20091130-3-fr-4008.00032.

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21

Gaitonde, Datta, J. S. Shang, and J. R. Edwards. "Structure of a Supersonic Three-Dimensional Cylinder/Offset-Flare Turbulent Interaction." Journal of Spacecraft and Rockets 34, no. 3 (May 1997): 294–302. http://dx.doi.org/10.2514/2.3232.

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IGO, Naoki, and Kiyoshi HOSHINO. "2P1-C29 Control of air cylinder actuator using variable offset pressure." Proceedings of JSME annual Conference on Robotics and Mechatronics (Robomec) 2010 (2010): _2P1—C29_1—_2P1—C29_4. http://dx.doi.org/10.1299/jsmermd.2010._2p1-c29_1.

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23

Abe, Hiroshi, Tetsuo Yoshida, Hiromichi Kobayashi, and Kiyoshi Nakamura. "Temperature Dependence of Zero Offset of Piezoelectric-Ceramic Cylinder Vibratory Gyroscope." Japanese Journal of Applied Physics 35, Part 1, No. 9B (September 30, 1996): 5031–33. http://dx.doi.org/10.1143/jjap.35.5031.

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Zebiri, C. E., M. Lashab, D. Sayad, I. T. E. Elfergani, K. H. Sayidmarie, F. Benabdelaziz, R. A. Abd-Alhameed, J. Rodriguez, and J. M. Noras. "Offset Aperture-Coupled Double-Cylinder Dielectric Resonator Antenna With Extended Wideband." IEEE Transactions on Antennas and Propagation 65, no. 10 (October 2017): 5617–22. http://dx.doi.org/10.1109/tap.2017.2743741.

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Winklhofer, Ernst, Siegfried Loesch, Stefan Satschen, and Bernhard Thonhauser. "Reduction of Friction Losses by Means of Cylinder Liner Offset in a Floating Liner Single Cylinder Engine." International Journal of Automotive Engineering 9, no. 4 (2018): 304–9. http://dx.doi.org/10.20485/jsaeijae.9.4_304.

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Jia, Libin, Jeffrey Naber, and Jason Blough. "Application of FRF with SISO and MISO model for accelerometer-based in-cylinder pressure reconstruction on a 9-L diesel engine." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 229, no. 4 (June 5, 2014): 629–43. http://dx.doi.org/10.1177/0954406214538009.

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Engine control with feedback from engine combustion process diagnostics can help improve fuel efficiency and assist in meeting stricter emission regulations. The standard is to use in-cylinder pressure measurements with analysis including rate of heat release. The measurement is usually obtained with intrusive sensors that require a special mounting process and engine structure modification. The potential of the low-cost non-intrusive accelerometer as an alternative means to reconstruct the in-cylinder pressure has been demonstrated by previous investigations. In this work, start of injection (SOI) sweep test conditions at varied speed spanning both low load and high load were conducted on an inline 6-cylinder, 9 L diesel engine. The relationship between the in-cylinder pressure and the accelerometer signal was quantified with frequency response function (FRF). The robustness of the obtained FRF was evaluated by applying the single-test-based FRF to reconstruct the in-cylinder pressures for other test conditions. Two models, single-input single-output (SISO) and multiple-input single-output (MISO), were investigated and compared where the accelerometer signal was taken as the input and in-cylinder pressure as the output. The optimal channel used to acquire the input signal in the SISO model was selected on the basis of coherence analysis. Results show that the MISO model assisted by principal component analysis (PCA) and offset-compensation processes can result in better in-cylinder pressure estimation than the SISO model for conditions with 2200 rpm engine speed. With the purpose of minimizing the cost for accelerometer employment, the minimum number of inputs used to reconstruct the in-cylinder pressure in the MISO model was pursued. Thresholds were set based on three estimated in-cylinder pressure parameters to select the qualified input channels and two input channels were finally determined. Results showed that the two-input single-output FRF model coupled with the PCA and offset-compensation processes improves the FRF’s robustness for the in-cylinder pressure estimation in comparison to the SISO FRF model based on all the tests conducted in this paper.

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Guo, Jun Zhong, and Jun Ping Yang. "Impact Analysis of Piston Velocity to Cylinders Motion on Pneumatic Impression On-Off Mechanism of Sheet-Fed Offset Press." Advanced Materials Research 215 (March 2011): 327–31. http://dx.doi.org/10.4028/www.scientific.net/amr.215.327.

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The impression on-off mechanism is an important part of the offset press, the design and manufacture have relationship with the performance of the printing presses and the quality of the printed products. Pneumatic impression on-off mechanism has the advantages of high position accuracy, reliable and highly automation. This article takes pneumatic impression on-off mechanism as the object of study, the three-dimensional digital model of the impression on-off mechanism is established and the process of on-off pressure is analyzed by using ADAMS software, the piston minimum velocity when the cylinders rotates in different angular velocity is obtained, through simulation, the relation between the motion of impression on-off mechanism and cylinder angular displacement is analyzed. Finally, an important basis to adjust the piston velocity under different speed of cylinders rotation will be provided.

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Brata, Akas Sureng, Keiji Sasaki, and Shigeyuki Shimachi. "Cylinder Insertion into Hole of Flexible Rubber Plate - Insertion Force Related to Position and Posture of Cylinder -." Journal of Robotics and Mechatronics 10, no. 3 (June 20, 1998): 191–96. http://dx.doi.org/10.20965/jrm.1998.p0191.

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We discuss cylinder insertion into a hole of a flexible rubber plate. Rubber plate deformation is modeled using long beams aligned perpendicular to the hole. Insertion force is analyzed in relation to cylinder depth, offset and inclination. Insertion force forms a hyperbolic field in three-dimensional space composed of position and posture parameter coordinates. The magnitude of insertion force is discussed based on insertion trajectory in the hyperbolic field. A human inserting a cylinder might angle it at the start of insertion, making it perpendicular to the rubber surface at the end. The human's sequence uses a trajectory that minimizes insertion force. We show experimentally a hyperbolic field in position and posture space.

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Jurkiewicz, Agnieszka, and Yuriy Pyr'yev. "The Change of Printouts' Quality Depending on Pressure of a Blanket Cylinder Against an Impression Cylinder and a Plate Cylinder in Offset Machine." Acta Mechanica et Automatica 8, no. 1 (March 1, 2014): 9–15. http://dx.doi.org/10.2478/ama-2014-0002.

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Abstract According to lots of books, the pressure in offset printing affects the optical density and the quality of printouts. One of the quality parameters is a tone value increase. An advantage of our research method is obtaining printing effects for different pressures on one printout, thus meaning for identical printing conditions. We obtained the same printing conditions through using different amounts of underlay sheets fixed to the blanket cylinder, under a blanket. The pressure was increased from optimal settings - in accordance with the machine manufacturer’s recommendation. The test printouts were printed using Adast Dominant 515, on a coated and an uncoated paper. The optical density value was measured on the tone value scale from 10% to 100% stepping regularly by 10%. For this scale the tone value increase was computed. The research shows that for both types of paper the optical density and the tone value increase changes not very much above the optimal pressure recommended by the machine manufacturer. A difference in the optical density and in the tone value increase is bigger for coated paper than for uncoated paper. Changes in these two parameters are negligible in places where used form 0 to 4 underlay sheets and are quite significant in the place where 5 underlay sheets were.

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Liu, Deliang, and Shifeng Zhang. "The Influence of Barrel Offset on Cylinder Liner-Piston Ring Lubrication State." IOP Conference Series: Materials Science and Engineering 774 (March 27, 2020): 012140. http://dx.doi.org/10.1088/1757-899x/774/1/012140.

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Yamilinets, S. Yu, G. N. Zhuravleva, and A. P. Kondratov. "Chemical resistance of a surface of an offset cylinder of printing equipment." IOP Conference Series: Materials Science and Engineering 862 (May 28, 2020): 062107. http://dx.doi.org/10.1088/1757-899x/862/6/062107.

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Jia, Libin, Jeffrey D. Naber, and Jason R. Blough. "Frequency response function adaptation for reconstruction of combustion signature in a 9-L diesel engine." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 229, no. 17 (January 23, 2015): 3071–83. http://dx.doi.org/10.1177/0954406215569256.

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An accelerometer as a low-cost non-intrusive transducer for sensing the combustion events in a diesel engine was investigated via the reconstruction of in-cylinder pressure using an adapting frequency response function (FRF). As the noise introduced into the accelerometer signal and the response to combustion vary with the operating condition, the FRF computed from a single operating condition only works for the same or similar conditions. To overcome this limitation, an adaptation process for the FRF was explored. Robustness of FRF over additional operational conditions with start of injection, start of combustion, and load variations was greatly improved. Frequency domain analysis shows that only the low-frequency content is determinant for the in-cylinder pressure reconstruction, and the adaptation of the first and second (0 Hz and 121 Hz) harmonics of the FRF results in the greatest improvement for the in-cylinder pressure estimation accuracy. The 0 Hz harmonic is adjusted based on the pre-measured in-cylinder pressure offset and the online measured accelerometer signal offset. Particle swam optimization as a computational algorithm is applied to adapt the 121 Hz harmonic of FRF. The results show that the adapted FRF, in comparison to the unadapted FRF, can reduce the phase error up to 1.3 crank angle degrees and reduce the amplitude error by up to 90%.

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Liu, Dun, Chuan Zhen Huang, Jun Wang, Hong Tao Zhu, Peng Yao, and Zeng Wen Liu. "Study on the Effect of Standoff Distance on Processing Performance of Alumina Ceramics in Two Modes of Abrasive Waterjet Turning Patterns." Advanced Materials Research 797 (September 2013): 21–26. http://dx.doi.org/10.4028/www.scientific.net/amr.797.21.

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Abrasive waterjet (AWJ) turning is an emerging technology, which plays an important role in machining cylindrical parts with the distinct advantages of negligible thermal effects and extremely low cutting force. This paper presents an experimental study of abrasive waterjet turning (AWJT) of Al2O3ceramics. The machining process and performance in terms of the depth of penetration (DOP), surface roughness (Ra) and actual impact angle (β) are discussed to understand the effect of standoff distance (SOD) on the processing performance at two different turning modes. Based on the results of these investigations, there is a significant change ofDOPandRaat differentSODin radial mode turning and the optimalSODof gaining maximumDOPand the minimumRais about 5.5mm.However, theDOPis nearly independent on theSODin offset mode turning. SmallerRaandDOPcan be obtained in offset mode. Furthermore, the results indicate that the roundness error of cylinder parts is probably improved with the properSODinterval in radial mode turning and it is suitable for machining cylinder part with considerably different radial size. The offset mode turning as the next operation after radial mode turning is recommended to process workpiece with excellent roundness. In this way, by understanding the effect ofSODon processing alumina ceramics, the paper establishes a good basis for developing strategies for optimizing processing parameters in order to generate the desired part geometry and achieve better surface quality.

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Tunestål, P. "TDC Offset Estimation from Motored Cylinder Pressure Data based on Heat Release Shaping." Oil & Gas Science and Technology – Revue d’IFP Energies nouvelles 66, no. 4 (July 2011): 705–16. http://dx.doi.org/10.2516/ogst/2011144.

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Klein, Philipp, Matthias Schmidt, and Otmar Loffeld. "ESTIMATION OF THE CYLINDER PRESSURE OFFSET AND POLYTROPIC EXPONENT USING EXTENDED KALMAN FILTER." IFAC Proceedings Volumes 40, no. 10 (2007): 175–82. http://dx.doi.org/10.3182/20070820-3-us-2918.00025.

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Blair, W. L., D. P. Hoult, and V. W. Wong. "The Role of Piston Distortion on Lubrication in a Reciprocating Engine." Journal of Engineering for Gas Turbines and Power 112, no. 3 (July 1, 1990): 287–300. http://dx.doi.org/10.1115/1.2906494.

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The microgeometry of the piston, rings, and skirt relative to the liner strongly influences lubrication in a reciprocating engine. This study develops an approximation technique that decouples the thermomechanical piston-skirt distortions from the complex lubricant support in a large diesel engine. The model considers the limiting case of starved skirt lubrication with large clearance. It permits efficient design of machined three-dimensional piston-skirt contours for piston support. In the calculations, a three-dimensional finite-element model is coupled with a postprocessing algorithm to predict skirt distortions, piston tilt, operating clearance, and oil-film contact area as a function of machined profile, thermal expansion, cylinder pressure, piston inertia, and transient side loads. A piston dynamics model is developed that defines the transient piston side force based on engine geometry, cylinder pressure, inertial loads, and wrist-pin offset. The results of this study indicate that (1) the transient skirt distortions due to cylinder pressure on the compression and power strokes result in a significant increase in oil-film contact area; (2) the piston skirt operating shape depends on the location and area of oil-film contact; (3) the contact area and location during intake and exhaust strokes vary substantially from that during the compression and power strokes; (4) the wrist-pin offset reduces the maximum side load and piston slap intensity occurring in the region of maximum cylinder pressure; (5) effective three-dimensional skirt profile design may result in significant changes in oil-film contact area and location on the skirt throughout the cycle.

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37

Guo, Jun Zhong, Tian Tian Cai, and Shi Ying Zhao. "Control and Regulation of Following Pressure Regulating Device in Offset Press." Applied Mechanics and Materials 312 (February 2013): 762–65. http://dx.doi.org/10.4028/www.scientific.net/amm.312.762.

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In this paper, the single and double eccentric combination of pressure regulation device in the offset press was as the object. A closed loop control system of printing pressure and a following pressure regulation device were designed. The rotation angle of eccentric bearing in plate cylinder and the length change of regulating screw were worked out by means of the vector relationship of pressure regulation. The influence on printing quality from the pressure regulation device was analyzed, and it provided a certain basis for the regulation and control of printing pressure.

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Peiyou, Xiong, Geng Daojing, Hao Guannan, Zhang Jian, Guo Wei, Zhao Wenbin, and Chen Li. "Influence of piston pin hole offset on cavity erosion of diesel engine cylinder liner." Engineering Failure Analysis 103 (September 2019): 217–25. http://dx.doi.org/10.1016/j.engfailanal.2019.04.022.

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Lv, Chuan Dong, Ji Fei Cai, Guang Li, and Rui Ming Fang. "Study on the Effect of Brush Roller to Blanket." Advanced Materials Research 591-593 (November 2012): 2143–47. http://dx.doi.org/10.4028/www.scientific.net/amr.591-593.2143.

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Brushes-type blanket washer’s function is rubbing a high speed spinning brush roller against blanket roller, so as to clean the paper-lints and ink which adhere to the surface of blanket cylinder. It is very important to do a research into the dynamic structural analysis of the washer which determines the stability of this equipment. With the gyroscopic effect dynamic analysis of brush blanket, we get the relation curve between central offset of the washer and the load of permanent joint. The result show that a minute alteration of the central offset causes effect change of the load. This result provides a theoretical basis to control the effect change and then improve the stability and decrease the cost.

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Dendge, Ramesh R. "Analysis of Printing Pressure Using Density Measurements of Printed Ink." SAMRIDDHI : A Journal of Physical Sciences, Engineering and Technology 11, no. 01 (July 25, 2019): 39–46. http://dx.doi.org/10.18090/samriddhi.v11i01.6.

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In process-color lithographic sheet-fed offset printing the uniformity of printing pressure is critical in achieving consistent print quality. The variations in printing pressure at blanket and impression cylinder nip affect the resultant print density of process colors. The variations in printing pressure are observed not only within the print run but also in the print area of the sheet. The printing pressure is the function of machine engineering, blanket cylinder covering material, substrate, and thickness of image carrier, packing materials used in packing of blanket and plate cylinder. Many printers, even today, use a feeler gauge to judge the level of printing pressure at two or three places along with the blanket and impression cylinder nip. The conventional feeler gauge method yields qualitative information and considers a very smaller portion of the print area. In this experimental work, the densitometry is used to devise an alternative subjective method to give information about the levels of printing pressure across the print area. The image equalling print area is divided into uniformly spaced small patches and one thousand sheets uncoated paper are printed with cyan color on large format offset printing machine. Three sheets, 101th, 501th, and 901th, representing the start, middle and the end of the print run are selected. Out of each identified sheets, three patches are selected from left middle and right columns giving a total nine locations from across the print area. The reflection densities, of nine cyan patches uniformly covering the print area, are measured using electronic densitometer for each of the sheets and tabulated. This approach, involving statistics, is aimed at providing a quantitative tool to analyze printing pressure variation across the print area and within the print run.

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Kim, Chung Hwan, Ha-Il You, and Seung-Hyun Lee. "Register control of roll-to-roll gravure-offset printing equipment considering time difference between measurement and actuation." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 226, no. 11 (January 3, 2012): 2726–38. http://dx.doi.org/10.1177/0954406211433247.

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The manufacture of printed electronics by roll-to-roll printing machine requires more accurate register performance than conventional media printing technology. Moreover, high drying temperature and long drying time to sinter the inks can induce the substantial changes in the length of the substrate and consequently register errors. Among the roll-to-roll printing methods, the gravure one, despite its relatively fast productivity and fine-line printing capacity, has difficulty in achieving the required register specifications for printed electronics because of the dependence of the register control on web dynamics. This study proposes a roll-to-roll gravure-offset printing equipment, including the register measurement system designed to enhance register performance and the related register control method for the application of printed electronics. Each cylinder constituting the printing unit is driven independently by an individual servomotor. Moreover, the printing patterns of the plate cylinder can move in the axial direction by position control, as well as in the web transport direction by a phase shift of the plate cylinder, without affecting the dynamics of the web. The time difference between the measurement and the actual control action is considered and modeled. The register measurement system, including selections of sensors and marks is also proposed to consider the effect of the time difference. The simulation results and the experiments of the register control are shown to verify the effect of the time difference on the control performances. It is found that a proper estimation of time difference should be obtained in order to guarantee more accurate and stable control performances.

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Hassan, Taj Elssir, Abdelfattah Bilal, and Maisara Mohy Eldin Gasim. "Theoretical Performance Comparison between Inline, Offset and Twin Crankshaft Internal Combustion Engines." FES Journal of Engineering Sciences 3, no. 1 (November 6, 2008): 17. http://dx.doi.org/10.52981/fjes.v3i1.76.

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The twin crankshaft engine is anew configuration of internal combustion engine that introduced to solve the engine liner wear problems, increase the engine efficiency and it has other advantages over conventional engines. In this research, a computational work was carried out to compare the performance of three l engine configurations, namely, the conventional (inline) engine, the offset crankshaft engine and the twin crankshaft engine, of the same cylinder bore, speed, crank arm, piston mass and heat addition. The performance measured was the side thrust force that causes liner wear and the output torque. Results showed that the twin crankshaft engine is superior in terms of torque which means it has larger efficiency than the other configurations.

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Cao, Li Bo, Wen Tao Cheng, Xiang Nan Shi, Jie Chen, and Li Quan. "Development and Validation of Offset Deformable Barrier Model with Beam Element." Applied Mechanics and Materials 128-129 (October 2011): 1139–42. http://dx.doi.org/10.4028/www.scientific.net/amm.128-129.1139.

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According to GB/T 20913-2007 regulation, the finite element model of the offset deformable barrier (ODB) was built with beam and shell elements, and validated in the simulation of quasi-static compression test. In order to analyze the local deformation characteristics of the ODB model, a sled test was designed. A cylinder impactor of 110 mm in diameter was welded in front of the sled. It was used to impact the fixed ODB. The simulation model of this test was also built. The acceleration of the sled and the deformation of the ODB were measured in the test and compared with the simulation data. The results show that the ODB model with beam elements not only satisfies the demands of the regulations, but also has good local deformation characteristics. The efficiency of computing can be improved obviously with beam elements.

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Gnana Sagaya Raj, A., J. M. Mallikarjuna, and V. Ganesan. "Flow Investigation on Different Combustion Chamber Configuration in a DI Diesel Engine – A CFD Approach." Advanced Materials Research 505 (April 2012): 420–23. http://dx.doi.org/10.4028/www.scientific.net/amr.505.420.

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The main objective of the present investigation is to make a computational study of flow structure inside the engine cylinder in a DI diesel engine during the end of compression stroke at an engine speed of 1000 rev/min. The analysis has been carried out for four different piston configurations viz., flat piston, centre bowl on flat piston, inclined and inclined offset bowl piston. A polyhedral trimmed cell has been adopted for meshing the geometries using the code called STAR-CD Es-ice. The flow has been simulated by solving the governing equations of conservation of mass, momentum and energy using the SIMPLE algorithm. From this numerical prediction, the best possible combustion chamber configuration and the location of fuel injector on the cylinder head have been arrived.

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Achmadi, Hendra. "CBS (Contrastrain Based Schedulling) adalah Faktor Penentu Keberhasilan Perusahanan Printing." ComTech: Computer, Mathematics and Engineering Applications 1, no. 1 (June 1, 2010): 75. http://dx.doi.org/10.21512/comtech.v1i1.2169.

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In a highly competitive industry faces today ranging from small or home-based printing to using machine that can print offset a hundred thousand copies per hour. But, the increasing competition resulted in requiring a faster production time from order entry, print proff until the production process to delivery to customers. Often times in case of orders which will result in the concurrent PPIC will experience vertigo in the setting of production schedules which have concurrent delivery time. Often will end up with no receipt of orders due to difficulties in the production schedule, especially if the orders require the same offset machine and cylinder wear the same length, while the number of cylinders is limited. Therefore, the printing company should be able to do so in the conduct of a penetration timing of production can easily be simulated and implemented on the ground. CBS (Base Constraint scheduling) is a technique to do the scheduling of production so that production can be carried out smoothly and quickly that fulfill the promise made to customers. In scheduling, there are several techniques that can be used are: FCFS (First Came First Serve), EDD (Earliest Date), and LCLS (Last Came Last Serve). So, it is required to be able to do way better scheduling to get results quickly in this fast changing schedules.

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Parker, J. K., S. R. Bell, and D. M. Davis. "An Opposed-Piston Diesel Engine." Journal of Engineering for Gas Turbines and Power 115, no. 4 (October 1, 1993): 734–41. http://dx.doi.org/10.1115/1.2906767.

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Typical conventional diesel engine designs are based on arrangements of single piston and cylinder sets placed sequentially either in-line or offset (“V”) along the crankshaft. The development of other engines, such as the opposed piston type, has been motivated by potential advantages seen in such designs, which may not be viable in conventional in-line or V engine arrangements. Several alternatives to conventional engine design have been investigated in the past and some aspects of these designs have been utilized by engine manufacturers. The design and development of a proof-of-concept opposed piston diesel engine is summarized in this paper. An overview of opposed-piston engines is presented from early developments to current designs. The engine developed in this work is a two stroke and uses four pistons, which move in two parallel cylinders that straddle a single crankshaft. A prechamber equipped with a single fuel injector connects the two cylinders, forming a single combustion chamber. The methodology of the engine development process is discussed along with details of component design. Experimental evaluations of the assembled proof-of-concept engine were used for determining feasibility of the design concept. An electric dynamometer was used to motor the engine and for loading purposes. The dynamometer is instrumented for monitoring both speed and torque. Engine parameters measured include air flow rate, fuel consumption rate, inlet air and exhaust temperatures, and instantaneous cylinder gas pressure as a function of crank position. The results of several testing runs are presented and discussed.

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Ou Yang, Tian Cheng, Nan Chen, Cui Cui Ju, Cheng Long Li, and Jiang Hu Li. "Dynamic Analysis of Offset Printing Press Gear-Cylinder-Bearing System under Time-Varying Meshing Stiffness Effect." Key Engineering Materials 656-657 (July 2015): 658–63. http://dx.doi.org/10.4028/www.scientific.net/kem.656-657.658.

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This study propose a new nonlinear model for offset printing press gear-cylinder-bearing system by the lumped parameter approach. The multi-DOF model consists of helical gear pairs and spur gear pairs with time-varying meshing stiffness. Bearing and shaft flexibilities are include in the model as well. The equations of motion are obtained by Darren Bell principle and Runge-Kutta numerical method is used to slove the equations of motion. The results show that meshing stiffness and bearing stiffness significantly affect critical speed, vibration acceleration and meshing force. Multi-body dynamics software are applied to compare with lumped parameter model. The results show that there are many similarities in different aspects. Results of experimental study on offset printing press are also presented for validation of different models. After Discrete Fourier Transform, the graphics display that acceleration peaks frequencies are an integer multiple of the gear mesh frequency. It demonstrate that mechanical vibration is mainly from gear transmission system at high printing speed and gear transmission system lead to nonlinear vibration. This work provide a foundation for further improvement of the dynamics of gear system.

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Fouladi, Kamran, and Oktay Baysal. "Viscous Simulation Method for Unsteady Flows Past Multicomponent Configurations." Journal of Fluids Engineering 114, no. 2 (June 1, 1992): 161–69. http://dx.doi.org/10.1115/1.2910011.

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An algorithm is developed to obtain numerical simulations of flows about complex configurations composed of multiple and nonsimilar components with arbitrary geometries. The algorithm uses a hybridization of the domain decomposition techniques for grid generation and to reduce the computer memory requirement. Three-dimensional Reynolds-averaged, unsteady, compressible, and full Navier-Stokes equations are solved on each of the subdomains by a fully vectorized, finite-volume, upwind-biased, approximately factored, and multigrid method. The effect of Reynolds stresses is incorporated through an algebraic turbulence model with several modifications for interference flows. The algorithm is applied to simulate supersonic flows past an ogive-nose-cylinder near or inside a cavity. The cylinder is attached to an offset L-shaped sting when placed above the cavity opening. The unsteady nature of these flowfields and the interaction of the cavity shear layer with the cylinder are simulated. These cases illustrate two significantly different and important interference characteristics for an internally carried store separating from its parent body. Unsteadiness of the cavity flow has a more pronounced effect on the normal forces acting on the cylinder when the cylinder is placed inside the cavity. The time averaged surface pressures compare favorably with the wind tunnel data, despite the averaging time period for the computations being three orders of magnitude smaller than that of the experimental measurements.

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Zhao, Ji Bin, and Xiu Li Li. "Testing and Research on Inking Properties of Offset Press." Advanced Materials Research 174 (December 2010): 319–22. http://dx.doi.org/10.4028/www.scientific.net/amr.174.319.

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A new testing form was designed, in which the screens having gray scales and some solid blocks were included. The screens consist of gray scales from 0 to 100% of dot coverage, and the solid blocks also have coverage scales from 0 to 100%. Printing experiment was performed, and densities and dot coverage of specific places were measured and recorded. Based on the testing data, density or dot coverage undulation with printing impressions was indicated by curves. Furthermore analysis was taken. Dot gains in the same prints are not constant, which cause that saddle shape in prints. Some reasons from construction of press such as the gap of cylinder, swing of transferring roller and oscillation of oscillating rollers were brought out. Same values of ink presetting can not get the same printing quality in the ink zones which have the same graphic coverage. The traditional press has a long make-ready time in printing running, which can reduce the efficiency of press. Shaft-less technology of inking system is put forward to cut down the make-ready time and to decrease the power consumption. New algorithm research is necessary for ink zone presetting in order to get more precise ink feeding. Some research on the press construction is also important for the press having some inherent defects

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Bian, J. H., W. T. Niu, L. N. Wang, Z. H. Liu, and P. F. Wang. "Study of Steering Actuator of Static “Point-the-Bit” Rotary Steerable System." Materials Science Forum 697-698 (September 2011): 665–70. http://dx.doi.org/10.4028/www.scientific.net/msf.697-698.665.

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This paper describes a new steering actuator of static “point-the-bit” rotary steerable system (RSS). It works by controlling the bias unit to give the mandrel an offset to the original axis, so as to drive the drill bit deviation from the borehole axis. The bias force is provided by the hydraulic cylinder. The steering actuator introduces two universal joints, which effectively improved the conditions of bearing high alternating stress, and the build up rate of the system. Mandrel’s static and kinematic equations were established on the basis of simplifying the mechanical structure model of the mandrel and bearing. Bending angle and deflection curve equation were derived and the position of the hydraulic cylinder was optimized. At last, the paper gives the control model of the bias unit.

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Journal articles on the topic 'Cylinder offset'

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