Papers by Keyword: Drive Screw

Abstract: The ball screw drive system is obtained widespread application in the modern machine. Along with the improving of feeding velocity and working precision, its dynamic analysis becomes more and more important. Considering the bearing stiffness and the contact deformation between the worktable and the screw, the drive screw is seen as a bar under elastic supports at both ends and with an internal moving elastic support. Using boundary conditions and matching conditions, the longitudinal vibration frequency equation of the screw is derived and the mode shape of the screw is solved. The vibration frequency is analyzed when the worktable moves from the left to the right end of the screw. The effect of the system parameters on the natural frequency and the mode shape are studied to supply a base for designing the drive system.

Abstract: The design and development of a screw-drive in-pipe robot is presented. The robot is composed of power-driving module, walking orientation module, universal joints, and accessories. The application of automatic spring structure on the robot improves its adaptability. The robot is able to move smoothly in the vertical, inclined, or horizontal pipelines, or even when the cross-section of the pipe is not strictly circular. The calculation formulae of robot walking speed and motor driving torque are derived in this paper. According to the geometries at the bend and the motion constraints, the robot turning capacity and turning condition are also analyzed. The vertical, bend, and other tests are performed on the experimental prototype, demonstrating that the screw-drive in-pipe robot provides sufficient tractive forces and good maneuverability and adaptability.

Abstract: The drive screw is simplified as a rotating Tinoshenko beam under the pre-tension force. Using boundary conditions and continuity conditions, the frequency equation of the screw with the elastic supports is derived considering the effect of gyroscope, the pre-tension force, the bearing stiffness, and the contact between the worktable and the screw. The effect of the system parameters on the lateral natural frequency is studied to supply a base for designing the drive system.