No.1019E 2023Special Edition on Automotive Technologies Simulation of Meshing Rack and Pinion for Steering Systems

Systems Innovation R&D Dept., Research & Development Division
Abstract Rack and pinion systems used for steering systems present several unique points. The first is that the racks used are generally round, and are supported without restraint against rack rotation. Second, the rack is supported by a spring that is pressed against the pinion, and under no or light load, the front and back tooth surfaces mesh. Because of this unique structure, conventional meshing simulation, which determines the distributed load on tooth surfaces, has not been applied. The influence of distributed load on performance is significant and should be evaluated at the design stage. This influence was dealt with by adding the equivalent error of tooth surfaces due to the motion of the rack and the distributed load due to the meshing on the back tooth surface to the conventional tooth deformation formula used for meshing simulation. As a result of the analysis, it was confirmed that the displacement caused by the rack behavior and the meshing of both tooth surfaces, which is unique structure of steering rack and pinion systems, could be reproduced. Verifi cation was also performed using actual equipment.
Keyword steering system, rack and pinion, meshing simulation, tooth deformation formula

1) T. KOBAYASHI, H. SHIBATA: Estimation of Rack Swing Torque for Rack and Pinion Steering Gear, JTEKT ENGINEERING JOURNAL, No. 1006E (2009) 23-30.

Search tag

Download Ranking of