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Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ordnance Industry Automation is the property of Editorial Board for Ordnance Industry Automation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract A crawler system provides much larger ground contact, leading to excellent terrain adaptability. Due to its structural characteristics, high‐frequency vibration proportional to the vehicle speed is generated during the driving process. This is a result of the polygon and rolling effects between the track and the wheels. A field test of a tracked vehicle is performed to monitor movement signals of the chassis and a rocker arm. Their corresponding power spectral density distributions confirm the correctness of the frequency‐calculation equation. Then, a novel elastic track tensioning device with a damper is designed as a cushion between the idler and the chassis. Depending on its geometry, the equivalent damping coefficient for a dynamic model is evaluated. Subsequently, the damping is altered in response to different operating conditions by a hybrid damping fuzzy semiactive control system. The controller accounts for both chassis and track vibration. Based on the transfer matrix method for multibody systems, a dynamical model of the track system is developed. Control performances are evaluated using two numerical simulations of obstacle crossing and off‐road driving operations. Results indicate that the proposed semiactive tensioner is substantially better than the conventional one. This paper provides a novel feasible scheme for vibration reduction of tracked vehicles.

Based on the meshing theory of silent chain, a new type of silent chain transmission system, the multi-phase Hy-Vo silent chain transmission system is proposed. The calculation method of the involute tooth profile equation for each phase sprocket is presented. The meshing design system is built. The Fourier series of lateral fluctuation quantity is established. The rationality of design and calculation is verified by computer simulation analysis. Compared with single-phase and double-phase silent chains, the polygonal effect of multi-phase Hy-Vo silent chain transmission system is smaller. It could provide a theoretical basis for the multivariate variation of silent chain. Communicated by John McPhee. [ABSTRACT FROM AUTHOR]

Scraper conveyor chain and chain gear transmission as the research object,analysis of the scraper conveyor load and no-load conditions chain dynamics,and numerical simulation of the scraper conveyor special point chain speed and tension are simulated. The results showed that: the most important parameter of the chain is the number of sprocket teeth,and the running stability of the scraper conveyor is proportional to the number of sprocket teeth,13 tooth sprocket stability is far stronger than 9 tooth sprocket scraper conveyor; polygon effect there side impact load on the chain tension fluctuation significantly higher than the no-load side; the reaction sensitivity of polygon effect is inversely proportional to the length of the chain length of the scraper conveyor and sprocket selection provides a theoretical basis,and to Study on dynamic characteristics of research methods and provides a theoretical basis.

The calculation of meshing force between chain links and sprocket is one of the chain transmission dynamics research focus. An approximate equation of sprocket meshing force is derived,under the condition of the local deformation before and after a single roller engaged with the tooth. Taking the main chain drive of a certain round balers as the research object,the dynamic characteristics and meshing force of main chain transmission system with multi-driven wheels in baling process of round balers under the condition of actual load torque are obtained through the simulation,the dynamics characterization of the chain drive system is analyzed and the validity of the model is verified,which present a certain operational method for actual agricultural machinery design.

Based on the meshing theory of the Hy-Vo silent chain plate-sprocket-cutter system, the basic meshing design system of dual phase Hy-Vo silent chain is built. The polygon effects of Hy-Vo silent chain are contrastingly analyzed through the geometrical analysis method in one-phase and dual phase transmission systems. The ideal multi-variation conditions of the parameters of Hy-Vo silent chain are reached. The calculation of inner meshing overhang is pointed out in dual phase transmission system. Combined with a specific example, the multi-body dynamic model of inner–outer meshing Hy-Vo silent chain is established in dual phase transmission system, and the relations of system fluctuation quantities are analyzed. The research shows that as the parameters of inner–outer meshing Hy-Vo silent chain in dual phase transmission system become closer to the ideal multi-variation conditions, the polygon effect is smaller. It could supply the theoretical basis for the parameter design of multi-variation of dual phase Hy-Vo silent chain transmission system, and provide the theoretical instruction for the dynamic meshing analysis of dual phase Hy-Vo silent chain transmission system. [ABSTRACT FROM AUTHOR]

The pushing chain mechanism is a novel telescoping mechanism used to push objects from one position to another rapidly. For obtaining a long telescoping distance, this mechanism adopts a helicoids case which can store links as many as possible. In order to analyze the dynamic properties and the pushing stability of the pushing chain, the dynamics models of its extraction from the helicoids case and engagement with the sprocket are established. Meanwhile, the dynamics model of the extended chain during the pushing process is deduced. A numerical simulation of the full dynamics model is performed using MATLAB. The simulation results show that the drive forces influenced by the polygon effect transit from drastic oscillations to smooth fluctuations. The traction force acted on the chain in the helicoids case drops down to zero gradually with time. The links of the extended chain have a transverse vibration around the pushing line and the amplitudes reach a maximum at the middle. However, the pushing velocity rises quickly at the initial stage and begins to stabilize with small fluctuation. The pushing chain mechanism has good pushing stability and high-speed performance. [ABSTRACT FROM AUTHOR]

The helicoid pushing chain mechanism is a novel telescopic mechanism used to push objects from one position to another one rapidly. It occupies a minimal amount of space in the contact status. In constrained space the helicoid chain case adopted may store as many links as possible for acquiring a long telescopic distance. In order to analyze the influences of polygon effect and meshing impact on the dynamic properties and pushing stability of the unidirectional chain, the dynamics models are established for the processes of extracting the unidirectional chain from the helicoid chain case and it meshing with the sprocket. Meanwhile, the extended part is simplified as a multi-spring-damping system, and the dynamics model of pushing process is deduced. The full dynamics models is numerically simulated by using MATLAB software and Rung-Kutta method. The simulation results show that the drawing force acted on the unidirectional chain in the chaincase drops down to zero concussively over time, and the change of the thrust force transits form drastic oscillation to smooth fluctuation. Besides, the pushing velocity of the chain is nearly constant during the pushing process. Hence this mechanism has an excellent pushing stability. In addition, the established dynamics models are verified by the experimental measurement of the pushing velocity. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Measurement Science & Instrumentation is the property of Journal of Measurement Science & Instrumentation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on the theory that the Hy-Vo silent chain meshes with the sprocket, and the related condition that the Hy-Vo silent chain sprocket meshes with a tool, multi-variations of the Hy-Vo silent chain and sprocket are designed. The meshing design system of the dual phase Hy-Vo silent chain plate-sprocket-tool is built. The design method of the dual phase Hy-Vo silent chain transmission system is presented. Combined with a concrete example, the dual phase Hy-Vo silent chain transmission system model is established, and the dual phase transmission system is decomposed into two single-phase transmission systems. The research shows that the instantaneous transmission ratio of a dual phase transmission system may be different from the instantaneous transmission ratio of a decomposed single-phase transmission system. If the two pitches of the dual phase sprocket are equal and the two groups of pressure angles are the same, the largest fluctuation quantity of the dual phase transmission system is less in comparison with the single-phase transmission system, and the polygon effect is smaller. The design method will provide a corresponding theoretical guidance for the design of other multi-phase chain systems. [ABSTRACT FROM AUTHOR]

The polygon effect is a major factor affecting the dynamic characteristics of chain drive in oil saw chain system. It causes impact, noise and dithering of the saw chain and significantly affects the lifespan of oil saw. A simple analytical method is proposed for analyzing the dynamic response resulting from the polygon effect of an oil saw chain system by using the difference method for numerical approximation. A MATLAB program is implemented and then applied for the polygon effect analysis of a specific saw chain drive. Numerical results such as velocities and dynamic loads due to polygon effect are compared with experimental data to demonstrate the effectiveness of the new method. A good agreement is obtained. The proposed polygon effect analysis method can provide guidelines for oil saw chain design for better dynamic performance. [ABSTRACT FROM AUTHOR]