Dynamics of High Speed Roller Chain Drives

1995 ◽  
Author(s):  
Peter Fritz ◽  
Friedrich Pfeiffer
Keyword(s):  
High Speed ◽  
Contact Forces ◽  
System Structure ◽  
Unilateral Constraints ◽  
Roller Chain ◽  
Contact Configuration ◽  
Nonlinear Force ◽  
A Chain ◽  
The Impact ◽  
Chain Drives

Abstract This paper deals with roller chain drives applied in combustion engines. In order to find characteristics for an optimal design, all components of a chain drive are taken into account. For a detailed analysis of the chain strand vibrations and the contact configurations each chain link, sprocket and guide is treated as a separate body. A nonlinear force element describes the joint forces, including elasticity, damping, backlash and oil-displacement. To determine real contact forces between a link and a sprocket or a guide, the exact contour and the mutual dependence of the contacts are considered. The impact of one link may influence the other links in such a manner that their contact configuration may change. In the mechanical model these contacts are represented by unilateral constraints. Applying the formulation of the linear complementarities including additional inequality conditions, the determination of a valid contact configuration after a change in the system structure is simplified.

Modeling of Tread Block Contact Mechanics Using Linear Viscoelastic Theory3

2008 ◽  
Vol 36 (3) ◽  
pp. 211-226 ◽  
Author(s):  
F. Liu ◽  
M. P. F. Sutcliffe ◽  
W. R. Graham
Keyword(s):  
High Speed ◽  
Slip Rate ◽  
Material Model ◽  
Contact Forces ◽  
Block Modeling ◽  
Rate Dependent ◽  
Linear Viscoelastic Material ◽  
Linear Viscoelastic ◽  
The Impact ◽  
Good Agreement

Abstract In an effort to understand the dynamic hub forces on road vehicles, an advanced free-rolling tire-model is being developed in which the tread blocks and tire belt are modeled separately. This paper presents the interim results for the tread block modeling. The finite element code ABAQUS/Explicit is used to predict the contact forces on the tread blocks based on a linear viscoelastic material model. Special attention is paid to investigating the forces on the tread blocks during the impact and release motions. A pressure and slip-rate-dependent frictional law is applied in the analysis. A simplified numerical model is also proposed where the tread blocks are discretized into linear viscoelastic spring elements. The results from both models are validated via experiments in a high-speed rolling test rig and found to be in good agreement.

Limb/Ground Impacts and Unexpected Impacts Control Strategy for a Model of a Walking Robot Limb

2010 ◽  
Vol 164 ◽  
pp. 377-382
Author(s):  
Krzysztof Lipiński
Keyword(s):  
Control System ◽  
Normal Component ◽  
Contact Forces ◽  
Walking Robots ◽  
Unilateral Constraints ◽  
Multibody Model ◽  
Dc Motors ◽  
Tangent Direction ◽  
Analysis Of Dynamics ◽  
The Impact

The paper deals with numerical analysis of dynamics of walking robots. The focus is on limb/ground contact. Normal and tangent direction are considered separately. In the normal one, the contacts are modeled as unilateral constraints. In the tangent one, slip and friction are considered. As the contacts are unilateral, nonzero velocities could be present before the contact. These velocities diminish rapidly, and significant contact forces are present. The forces have destructive influence on the robot structure, and the impulsive changes of the arms velocities can disorient the control system. In the paper, the impact consequences are discussed, as well as consequences of installation of a 0/1 contact sensor. A 3D mechatronic multibody model of a quote of a robot is considered. Its limb is driven by DC motors and controlled by a dedicated control system. With the zero signals from the sensor, the control prevents a constant velocity of the limb end. The normal component of the velocity has to be stopped at the positive signals, and the motor current has to be reduced. Exemplary calculations are presented in the paper.

Study on Noise in New Roller Chain Drives

2012 ◽  
Vol 522 ◽  
pp. 598-601
Author(s):  
Wei Sun ◽  
Xiao Lun Liu ◽  
Wen Cheng Wang ◽  
Li Yan He ◽  
Jia Jun Liu
Keyword(s):  
Noise Reduction ◽  
Noise Level ◽  
High Speed ◽  
Low Noise ◽  
The Other ◽  
Metal Mesh ◽  
Roller Chain ◽  
Polyurethane Composite ◽  
Noise Characteristics ◽  
The Impact

In order to mitigate the impact and the polygon effect of the chain and the sprocket during the meshing process and achieve the purpose of noise reduction, a Hlow noiseH nanostructured metal mesh-polyurethane composite material split roller chain was designed by means of changing structure and material of chain roller. Noise testing and frequency spectrum analysis were conducted, for the new roller chain and the other three kinds of the same specification chains with different structural rollers, on the closed force flow noise test bench researched and developed independently. The results show that the new roller chain can absorb some of the impact energy, and reduce vibration and noise of chain drive. The noise level generated by the new roller chain is significantly lower than the other tested roller chains, especially in high frequency and high speed. The difference in noise level is actually 3-11dB in driving sprocket speed of 1000r/min, and a significant noise reduction is achieved. The results also verify low noise characteristics of the new roller chain and rationality of design method.

Design and Construction of a Machine to Evaluate the Forces in Roller Chain Drives

1992 ◽  
Author(s):  
James C. Conwell ◽  
Glen E. Johnson ◽  
S. W. Peterson
Keyword(s):  
Experimental Investigation ◽  
Impact Force ◽  
Normal Operation ◽  
Test Machine ◽  
Chain Drive ◽  
Roller Chain ◽  
Wide Range ◽  
The Impact ◽  
Chain Drives ◽  
Design And Construction

Abstract In this article, a brief history of chain drives is presented, and the design and construction of a machine to investigate chain drive force phenomena is discussed. The new test machine allows the measurement of the impact force between a roller and the sprocket during “seating” and it can also be used to measure the forces that exist in the link sides plates during normal operation (including start-up and shut down conditions). Data can be obtained for a wide range of chain loads and speeds. Two companion papers (“Experimental Investigation of the Impact Force that Occurs When a Roller Seats on the Sprocket During Normal Operation of a Roller Chain Drive” and “Experimental Investigation of the Forces in a Link Side Plate During Normal Operation of a Roller Chain Drive”, both presented at this conference) describe experiments that have been completed with this test machine.

On the Impact Intensity of Vibrating Axially Moving Roller Chains

1992 ◽  
Vol 114 (3) ◽  
pp. 397-403 ◽  
Author(s):  
K. W. Wang ◽  
S. P. Liu ◽  
S. I. Hayek ◽  
F. H. K. Chen
Keyword(s):  
Chain Structure ◽  
Momentum Balance ◽  
System Response ◽  
Roller Chain ◽  
Impulse Function ◽  
Static Approach ◽  
Axially Moving ◽  
Local Impacts ◽  
The Impact ◽  
Chain Drives

Experimental observation has shown that the most significant noise source in roller chain drives is from the impacts between the chain and the sprocket during their meshing process. Despite its importance, studies have not been made to thoroughly analyze the chain/sprocket impact dynamics and their interaction with the vibrating, axially moving chain structure. This paper presents a novel analysis which integrates the local meshing phenomena with the global system. An axially moving chain interacting with local impacts has been modelled and the momentum balance method is employed to derive the impulse function. A study is carried out to quantify the intensity of subsequent impacts. It is found that the impact intensity is significantly affected by the vibration characteristics and response of the moving chain, and vice versa. The classical quasi-static approach will create errors in predicting the impulse magnitude and system response. Meshing frequencies that will cause maximum and minimum impulses are analytically predicted. This fundamental investigation provides new insight into roller chain dynamics, which is an essential step toward the design of quiet chain drives.

scholarly journals A Refined Numerical Simulation on Dynamic Behavior of Roller Chain Drives

2004 ◽  
Vol 11 (5-6) ◽  
pp. 573-584 ◽  
Author(s):  
H. Zheng ◽  
Y.Y. Wang ◽  
K.P. Quek
Keyword(s):  
Dynamic Behavior ◽  
Layer Structure ◽  
Contact Forces ◽  
Noise Emission ◽  
Transient Vibration ◽  
Explicit Finite Element ◽  
Roller Chain ◽  
Element Technique ◽  
Geometry Simplification ◽  
Chain Drives

A refined numerical analysis of the dynamic behavior of roller chain drives is performed considering the roller assembly as a three-layer structure with mechanical clearance between each two of the mechanical components. Instead of using analytical method, explicit finite element technique is utilized for modeling and simulating the dynamic behavior of chain drives. The complete standard geometry of sprockets and all components of chain links are used in the developed model with minor geometry simplification. A primary goal is to achieve a more complete understanding of the dynamic behavior of chain drives especially in the transient vibration response of the engaging rollers, which is crucial for noise emission calculation. The simulated velocity response of the engaging rollers and roller-sprocket contact forces achieved using the full model are compared with what found by the simple model which has been adopted in analytical study of chain roller dynamics.

Dynamics of CVT Chain Drives: Mechanichal Model and Verification

1997 ◽  
Author(s):  
Jürgen Srnik ◽  
Friedrich Pfeiffer
Keyword(s):  
Power Transmission ◽  
Contact Forces ◽  
Coulomb’S Friction ◽  
Joint Forces ◽  
Chain Link ◽  
Frictional Forces ◽  
Contact Situation ◽  
A Chain ◽  
Chain Drives ◽  
Chain Links

Abstract This paper deals with the dynamics of continuously variable (CVT) chain drives. According to the discrete structure of the chain, which causes the polygonal actions, the mechanical model contains each chain link and pulley as a separate body. While a chain link is part of a strand, only joint forces including friction act on the chain links, whereas in the contact situation additional impulsive and frictional forces in the contact zones between the chain link’s rocker pins and the tapered surfaces of the cone pulleys have to be taken into account. For the calculation of the contact forces Coulomb’s friction law as well as a time sparing continuous approximation are applied. Simulation results show the influence of the cone pulley’s deformation on the power transmission. They also show the repercussion of the polygonal action. Furthermore the chain’s pitch influence on the vibrational behavior of the transmission is discussed. A comparison of calculated and measured tensional forces verifies the model presented.

scholarly journals Vibration of Roller Chain Drives at Low, Medium and High Operating Speeds

1993 ◽  
Author(s):  
Woosuk Choi ◽  
Glen E. Johnson
Keyword(s):  
Boundary Conditions ◽  
Transverse Vibration ◽  
Equations Of Motion ◽  
Time Dependent ◽  
Partial Differential ◽  
Periodic Load ◽  
Roller Chain ◽  
Axially Moving ◽  
The Impact ◽  
Chain Drives

Abstract A model based on axially moving material is developed to study transverse vibration in roller chain drives. A unique feature of the work presented in this study is that impact, polygonal action and external periodic load have been included through chain tension and boundary conditions and periodic length change is also considered. The impact between the engaging roller and sprocket surface is modeled as a single impact between two elastic bodies and the modeling of the polygonal action is based on a four bar mechanism (rigid four bar at low speeds, elastic four bar at moderate and high speeds). At low and medium operating speeds, the system equation of motion for the chain span is expressed as a mixed type partial differential equation with time-dependent coefficients and time-dependent boundary conditions. At high operating speeds, the system equations of motion are two partial differential equations for transverse and longitudinal vibrations respectively and they are nonlinearly coupled The effects on transverse vibration of center distance, the moment of inertia of the driven sprocket system, static tension, and external periodic load are presented and discussed. Solutions are obtained by a finite difference method and Galerkin’s method.

Reduction of Noise and Vibration in Roller Chain Drives

1977 ◽  
Vol 191 (1) ◽  
pp. 363-370 ◽  
Author(s):  
S. W. Nicol ◽  
J. N. Fawcett
Keyword(s):  
High Frequency ◽  
Noise Level ◽  
Experimental Tests ◽  
Chain Drive ◽  
Noise And Vibration ◽  
High Frequency Vibration ◽  
Roller Chain ◽  
Guide Device ◽  
The Impact ◽  
Chain Drives

Particularly at the higher sprocket speeds, one of the main sources of noise and high-frequency vibration in a roller chain drive is the impact which occurs each time the driving sprocket collects a roller from the chain span. A method of guiding the chain so as to virtually eliminate these impacts is described. Details are given of experimental tests in which a simply-constructed guide device greatly reduced the amplitude of the high-frequency vibration of a drive, and produced a very significant lowering of the noise level.

On the Impact Intensity of Vibrating Axially Moving Roller Chains

1991 ◽  
Author(s):  
K. W. Wang ◽  
S. P. Liu ◽  
S. I. Hayek ◽  
F. H. K. Chen
Keyword(s):  
Chain Structure ◽  
Momentum Balance ◽  
System Response ◽  
Roller Chain ◽  
Impulse Function ◽  
Static Approach ◽  
Axially Moving ◽  
Local Impacts ◽  
The Impact ◽  
Chain Drives

Abstract Experimental observation has shown that the most significant noise source in roller chain drives is from the impacts between the chain and the sprocket during their meshing process. Despite its importance, studies have not been made to thoroughly analyze the chain/sprocket impact dynamics and their interaction with the vibrating, axially moving chain structure. This paper presents a novel analysis which integrates the local meshing phenomena with the global system. An axially moving chain interacting with local impacts has been modelled and the momentum balance method is employed to derive the impulse function. Convergence of the impulse function is examined and a study is carried out to quantify the intensity of subsequent impacts. It is found that the impact intensity is significantly affected by the vibration characteristics and response of the moving chain, and vice versa. The classical quasi-static approach will create errors in predicting the impulse magnitude and system response. This fundamental investigation provides new insight to roller chain dynamics, which is an essential step toward the design of quiet chain drives.

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