Constant Velocity Joint Research Articles

506 ツェッパ形等速継手の保持器応力変動解析(ジョイントのモデリングとその応用,OS-19 マルチボディダイナミクス,総合テーマ「伝統を,未来へ!」)

To analyze cage stress of the Rzeppa constant velocity joint (CVJ), we construct the model of Flexible Multibody Dynamics that is using a direct integration method. This model is composed of these parts; cage is finite element mesh, shaft is the divided beam element and other parts are the rigid body. The correctness of this simulation model was confirmed by the experiment that measures the strain of the cage pillar. Then, we considered the cause where cage stress change was generated while CVJ is rotating.

Transverse vibration of multi-segment shaft system joined with multiple hinges

A driveshaft with discontinuities (i.e., joints) is a major component in various industries including marine and automotive ones. The segments of a multi-piece driveshaft in automotive applications are joined using constant velocity or universal joints or a combination of both. The design of the driveshaft of an automotive system is primarily driven by its natural frequency. This paper presents an exact solution for the vibration of a three-piece driveshaft with multiple intermediate hinges. Each joint is modelled as a frictionless internal hinge. The Euler-Bernoulli beam theory is used. Lumped masses are placed on each side of the joint to represent the joint mass. Equations of motion are developed using the appropriate boundary conditions and then solved exactly. Natural frequencies and mode shapes are obtained. Numerical results obtained here are compared with those obtained using experimental and analytical tools (e.g., finite elements). The solution should be of value to engineers interested in the design and optimisation of the driveline systems.

507 トリポード形等速ジョイントのスラスト力低減に関する研究(ジョイントのモデリングとその応用,OS-19 マルチボディダイナミクス,総合テーマ「伝統を,未来へ!」)

To achieve reduction of thrust force of a tripod constant velocity joint, some reduction methods are determined based on mechanisms inducing the thrust force. In these methods, a dual-contact method is selected because of very few design change. A theory inducing the thrust force between a roller and this dual-contact groove is constructed. By comparing theoretical results with computational ones using multibody dynamics approach, the appropriateness of this theory is verified. This paper also describes the effectiveness of the thrust force reduction by testing a prototype joint equiped with the dual-contact groove.

トリポード形等速ジョイントのローラ挙動とスラスト力に関する研究(<特集>D&D2009)

A tripod constant velocity joint is used in the driveshaft of front wheel drive vehicles. Thrust force generated by this joint causes lateral vibration in these vehicles. To determine mechanisms inducing the thrust force, a detailed model is constructed based on a multibody dynamics approach. Though the joint is equipped with three rollers and grooves, this model consists of principal parts concerned with one roller and groove in order to precisely analyze frictional phenomena occurring between the roller and the groove. These principal parts are defined as rigid bodies and are connected by force elements of contact and friction. The appropriateness of this model is verified by comparing computational and experimental results and it is clarified that the principal factors inducing the thrust force are three kinds of sliding friction force at a contact point between the roller and the groove. This paper also describes the reason that the third rotating order component of the thrust force is induced by one roller and groove.

Study on Roller Behavior and Thrust Force of Tripod Constant Velocity Joint

Tripod constant velocity joints are used in the driveshaft of front wheel drive vehicles. Thrust force generated by this joint causes lateral vibration in these vehicles. To determine the mechanisms inducing the thrust force, a detailed model is constructed based on a multibody dynamics approach. Although the joint is equipped with three rollers and grooves, this model consists of the principal parts for one roller and groove in order to precisely analyze frictional phenomena occurring between the roller and the groove. These principal parts are defined as rigid bodies and are connected by force elements of contact and friction. The appropriateness of this model is verified by comparing computational and experimental results and it is clarified that the principal factors inducing the thrust force are three kinds of sliding friction force at the point of contact between the roller and the groove. This paper also describes the reason why the third rotating order component of the thrust force is induced by one roller and groove.

Simulation and Physical Modeling of Forging Sequence of Bj Type Outer Race

The outer race of a constant velocity (CV) joint is an important automotive component that is difficult to be forged because its shape is very complicated and the required precision is high. Since traditional cold forging methods are not always capable of producing complexly shaped parts, such parts are often made by processes, which require intense machining operations at relatively high costs. Thus near net shape forging is an attractive option for producing of outer race. Actual problems in final ironing sequence are prevention of ductile fracture and surface defects in final product and true formation of internal ball grooves of the workpiece. In this study Cockroft&Latham failure criterion was applied to final ironing sequence. Finally physical modeling is down using lead. In order to investigate the flow of the billet material during forging, the experimentally obtained section profile of internal grooves as measured by a CMM is compared with simulation based profile.

A phenomenological friction model of tripod constant velocity (CV) joints

Constant velocity (CV) joints have been favored for automotive applications, compared to universal joints, due to their superiority of constant velocity torque transfer and plunging capability. High speed and sport utility vehicles with large joint articulation angles, demand lower plunging friction inside their CV joints to meet noise and vibration requirements, thus requiring a more thorough understanding of their internal friction characteristics. In this paper, a phenomenological CV joint friction model was developed to model the friction behavior of tripod CV joints by using an instrumented CV joint friction apparatus with tripod-type joint assemblies. Experiments were conduced under different operating conditions of oscillatory speeds, CV joint articulation angles, lubrication, and torque. The experimental data and physical parameters were used to develop a physics-based phenomenological CV joint dynamic friction model. It was found that the proposed friction model captures the experimental data well, and the model was used to predict the external generated axial force, which is the main source of force that causes vehicle vibration problems.

Research on the technology for outer race elliptical groove grinding with basin-like grinding wheel

A new grinding method that outer race elliptic track in ball basket constant velocity joint is ground by means of basin-like grinding wheel is proposed herein. Aiming at the grinding process with basin-like grinding wheel, the paper establishes the mathematical model, optimizes the parameters by using restrictive random direction method, studies the processing principle in detail, and analyzes the machining errors. The simulation results indicate that the theoretical error of elliptical groove ground by basin-like wheel will be reduced to the level of 0.001 mm. Then, the grinding experiments of elliptical grooves with the basin-like grinding wheel were completed, and the measurements of the grooves by portable arm coordinate measuring machine were carried out, which validates the feasibility of this grinding technology.

Decoupled and Homokinetic Transmission of Rotational Motion via Constant-Velocity Joints in Closed-Chain Orientational Manipulators

This paper presents novel 2DOF and 3DOF closed-chain orientational manipulators, whose end-effector motion is actuated in a decoupled and homokinetic way by frame-located motors via holonomic transmissions based on constant-velocity couplings. The functioning of these couplings is investigated and the conditions applying for homokinetic transmission to be preserved during simultaneous motor drive are revealed and implemented. As a result, decoupled and configuration-independent relations between the motor rates and the time-derivatives of the variables describing the end-effector orientation are achieved. The attainment of analogous relations between the motor speeds and the components of the end-effector angular velocity is conversely proven to be unfeasible. The problem of singularities is furthermore examined, showing that input-output homokinesis is not a sufficient condition for a globally uniform kinetostatic behavior of the mechanism, which may, indeed, possibly reach uncertainty singular configurations. The connecting chains of the most typical constant-velocity couplings are analyzed, in order to obtain analytical expressions for the functions on which such singularities depend. The influence of design parameters is accordingly inspected. The results are valuable for the type and dimension synthesis of closed-chain wrists free from direct kinematic singularities, and characterized by simple kinematics and regular input-output kinetostatic relations.

Development of steel grades for heat treated power train components: a review

The development of new carburising steel grades by Daido Steel for heat treated transmission parts is reviewed. These developments are driven by the need for cost reduction, weight saving, fuel economy and higher mechanical performance in new car models under development in response to environmental and economic demands. The next generation of gears will be peened, then vacuum carburised to improve fatigue and impact strength in lighter components designed with smaller tooth cross-sections, and new steels giving improved performance have been developed. Case studies of new steels for pulleys (allowing shorter carburising times) and constant velocity joints are also described.

Weight reduction with optimised longitudinal shafts

The engine/transmission unit shall be connected robustly, uniformly and without vibration with the differential. This was done in former times by “cardan shafts” and cardan joints with certain disadvantages. Nowadays GKN uses longitudinal shafts with constant velocity (CV) joints. One solution is called Direct Torque Flow (DTF) utilizes modern CV joints and fulfils the competing targets weight reduction and cost savings by eliminating the bolted connection.

Multibody dynamics analysis of the driveshaft coupling of the ball and tripod types of constant velocity joints

The paper proposes a multibody dynamic simulation to numerically evaluate the generated axial force (GAF) and plunging resistant force (PRF) practically related to the shudder and idling vibration of an automobile. A numerical analysis of the drive shaft coupling of a ball joint (BJ) and two plunging type joints, a tripod joint (TJ), and a very low axial force tripod joint (VTJ), are conducted using the commercial program DAFUL. User-defined subroutines of a friction model illustrating the contacted parts of the outboard and inboard joint are subsequently developed to overcome the numerical instability and improve the solution performance. The Coulomb friction effect is applied to describe the contact models of the lubricated parts in the rolling and sliding mechanisms. The numerical results, in accordance with the joint articulation angle variation, are validated with experimentation. The offset between spider and housing is demonstrated to be the critical role in producing the third order component of the axial force that potentially causes the noise and vibration in the vehicle. The VTJ shows an excellent behavior for the shudder when compared with the TJ. In addition, a flexible nonlinear contact analysis coupled with multibody dynamics is also performed to show the dynamic strength characteristics of the rollers, housing, and spider.

Influence of Axial Adjustment Force in Universal Ball Joint on vibrational load of front-wheel drive vehicle power unit

The technical article presents compensating axial force dependent on transmitting engine torque, suspension displacement and constant velocity joint design. Also authors showed influence of powertrain vibration on compensating axial force.

Thrust Force Analysis of Tripod Constant Velocity Joint Using Multibody Model

A tripod constant velocity joint is used in the driveshaft of front wheel drive vehicles. Thrust force generated by this joint causes lateral vibration in these vehicles. To analyze the thrust force, a detailed model is constructed based on a multibody dynamics approach. This model includes all principal parts of the joint defined as rigid bodies and all force elements of contact and friction acting among these parts. This model utilizes a new contact modeling method of needle roller bearings for more precise and faster computation. By comparing computational and experimental results, the appropriateness of this model is verified and the principal factors inducing the second and third rotating order components of the thrust force are clarified. This paper also describes the influence of skewed needle rollers on the thrust force and evaluates the contribution of friction forces at each contact region to the thrust force.

112 トリポード形等速ジョイントのローラ挙動とスラスト力に関する研究

112 トリポード形等速ジョイントのローラ挙動とスラスト力に関する研究

マルチボディモデルによるトリポード形等速ジョイントのスラスト力解析(<特集>D&D 2008)

マルチボディモデルによるトリポード形等速ジョイントのスラスト力解析(<特集>D&D 2008)

Boot for constant velocity joint

Boot for constant velocity joint

Secondary Torque in Automotive Drive Shaft Ball Joints: Influence of Geometry and Friction

Automotive drive shafts are made of two constant velocity joints coupled by an intermediate shaft. In general, the joint close to the gearbox is a plunging tripod joint, the movement of which serves suspension. The joint close to the wheel is a fixed ball type joint, which allows the steering movement. The article is devoted to secondary torque generated by the ball joint during torque transmission. This study is based on an ADAMS model in rigid bodies with local deformation at contact (Hertz theory) and on industrial test bench measurements. After geometrical representation of ball joint kinematics and before the secondary torque calculation, the ADAMS model is validated through the calculation of internal efforts, which are compared with the models and measurements already presented in the literature. Concerning the secondary torque study, measurements with an industrial test bench at the NTN TE Test Department and the ADAMS model show that the R6 component of the secondary torque (orthogonal to the joint plane) is found to be negligible with respect to the transmitted torque (<2 N m for 300 N m input torque). The results of the ADAMS model also show that the steering component of the secondary torque (in the joint plane and orthogonal to the wheel axis) does not only depend on the joint angle but also on the friction and sign of the transmitted power.

Development of a semi-empirical friction model in automotive driveshaft joints

High speed and sport utility vehicles with large joint articulation angle demand lower friction in automotive driveshaft joints to meet noise and vibration comfort levels. Thus a more thorough understanding of internal friction characteristics and mechanisms is required. In this paper, a friction model in automotive driveshaft joints was developed through the use of test data from an instrumented Constant Velocity (CV) joint friction apparatus with actual driveshaft assemblies. Experiments were conducted under different realistic operating conditions of oscillatory speeds, CV joint articulation angles, lubrication, and torque. The experimental data was used to develop a physics-based semi-empirical CV joint internal friction model as a function of different CV joint operating parameters. It was found that the proposed friction model captures the experimental results well. Also the friction model estimates the generated axial force (GAF) in tripod CV joints well, which is the main source of force that causes vehicle vibration problems.

Research on elliptical groove grinding for plunging constant velocity joint with basin grinding wheel

The theoretical error of elliptical groove in outer race of plunging constant velocity joint ground by finger grinding wheel is about 0.004 mm. In order to decrease the error, a new grinding method with basin grinding wheel is proposed. When we optimize the design parameters, the basin grinding wheel will avoid the problems that the feasibility and grinding accuracy are restricted by the interference of the head in the grinding process by means of finger grinding wheel, and can be used to ensure the machining precision and the sectional shape of the raceway to the greatest extent. Aiming at the grinding process with basin grinding wheel, the paper establishes the mathematical model, optimizes the parameters by using simplex algorithm, studies the processing principle in detail, and analyzes the machining errors. The simulation results indicate that the theoretical error for elliptical groove ground by basin grinding wheel will be reduced to 0.631 μm.