Modern Transmission Mechanism of Production Machines

Ha Nguyen Van, M.Sc.

Doctoral thesis

Abstract:

Cam design is constantly evolving. In recent years, with the rapid development and popularization of mechanical products in modern society, it has been such an important question on designing and producing mechanisms precisely. Also, together with the assistance of the numerically controlled manufacture system being widely applied in this time, which are useful tools for the designer to develop a new type of cam profile. Therefore, this dissertation mainly focuses on designing a novel cam mechanism for converting the rotation cam to a desired rotary motion of the output shaft. The design based on the idea of altering the roller follower by the ball for a groove cam mechanism. Where the ball plays a roller of the follower in a conventional cam follower. Due to the balls connect the grooving cam and the grooves of the output shaft, they perform pure rolling motion without sliding. Hence, the main function of the balls transfers the moments and velocities from the camshaft into the output shaft. With the input, the body is the groove cam and the output shaft is driven one. Due to the contact between the balls with their grooves on each part of the cam mechanism is very important can directly affect the lifespan and the ability working of the structure of the groove cam. Therefore, the thesis also determines the contact stress between the ball and the grooves on output camshaft, middle part as well as a circular groove on the input camshaft by using both theory and fine element analysis methods. Through contact analysis, the changes could be shown in contact pressure, strain, penetration, friction stress on the groove cam mechanism. Based on the results simulation by ANSYS Workbench can aid the designer to redesign the model to obtain the optimal design. Finally, from the simulation results revealed that the computational values were consistent with theoretical values. It can be concluded that the proposed design has been successfully designing. Finally, the groove cam mechanism was manufactured successfully at the Laboratory of Department of the Design of Machine Elements and Mechanism of Technical University of Liberec, Czech Republic.

Abstract:

Cam design is constantly evolving. In recent years, with the rapid development and popularization of mechanical products in modern society, it has been such an important question on designing and producing mechanisms precisely. Also, together with the assistance of the numerically controlled manufacture system being widely applied in this time, which are useful tools for the designer to develop a new type of cam profile. Therefore, this dissertation mainly focuses on designing a novel cam mechanism for converting the rotation cam to a desired rotary motion of the output shaft. The design based on the idea of altering the roller follower by the ball for a groove cam mechanism. Where the ball plays a roller of the follower in a conventional cam follower. Due to the balls connect the grooving cam and the grooves of the output shaft, they perform pure rolling motion without sliding. Hence, the main function of the balls transfers the moments and velocities from the camshaft into the output shaft. With the input, the body is the groove cam and the output shaft is driven one. Due to the contact between the balls with their grooves on each part of the cam mechanism is very important can directly affect the lifespan and the ability working of the structure of the groove cam. Therefore, the thesis also determines the contact stress between the ball and the grooves on output camshaft, middle part as well as a circular groove on the input camshaft by using both theory and fine element analysis methods. Through contact analysis, the changes could be shown in contact pressure, strain, penetration, friction stress on the groove cam mechanism. Based on the results simulation by ANSYS Workbench can aid the designer to redesign the model to obtain the optimal design. Finally, from the simulation results revealed that the computational values were consistent with theoretical values. It can be concluded that the proposed design has been successfully designing. Finally, the groove cam mechanism was manufactured successfully at the Laboratory of Department of the Design of Machine Elements and Mechanism of Technical University of Liberec, Czech Republic.

Keywords

Groove cam, cam groove optimization, ball transition, contact analysis, novel cam, groove ball transmission

Language used: English

Date on which the thesis was submitted / produced: 14. 3. 2019

Thesis defence

• Supervisor: prof. Ing. Ladislav Ševčík, CSc.

Technical University of Liberec

Faculty of Mechanical Engineering

Doctoral programme / field:
Machines and Equipment / Machine and Equipment Design