Test method for jumping change of friction coefficient of worm gear and worm in automobile steering system

Abstract

A method for testing a jumpy variation in the fitting friction coefficient between a worm gear and a worm of an automobile steering system, comprising: rotatably arranging a worm gear assembly (2) on a worm gear fixing device (5), rotatably arranging a worm assembly (1) on a worm fixing device (4), and meshing the worm assembly (1) with the worm gear assembly (2); applying a pressure F to the worm assembly (1) and rotating the worm assembly (1); measuring the rotation torque T of the worm assembly (1); calculating the fitting friction coefficient between the worm gear and the worm; and plotting a graph of the jumpy variation in the fitting friction coefficient between the worm gear and the worm. The testing method applies a traditional method for testing a friction coefficient to the test of a jumpy variation of a friction pair between the fitted worm gear and worm of a reduction mechanism of a columnar electrically steering system. The method is simple and useful, and the implementation cost is low. Problems can be found in advance by this testing method during early design of a reduction structure, and the mechanical noise produced by the worm gear and the worm can be avoided in advance, thereby reducing the cost and period of post-design changes.

Description

technical field [0001] The invention belongs to the technical field of automobiles. Specifically, the invention relates to a method for testing the jumping change of the friction coefficient of a column-type electric steering system reduction mechanism of a worm gear and a worm. Background technique [0002] With the development of the automobile industry, the traditional hydraulic steering system is used less and less. In order to improve the handling performance and comfort of the vehicle, as well as reduce the fuel consumption of the vehicle, more and more vehicles use the electric steering system, and the current More than half of the electric steering system adopts column electric steering system. [0003] The worm gear of the deceleration mechanism of the column-type electric steering system is easy to produce mechanical noise. As customers have more and more stringent requirements for vehicle comfort, if the mechanical noise of the vehicle steering system components i...

AI Technical Summary

Problems solved by technology

[0003] The worm gear of the deceleration mechanism of the column-type electric steering system is easy to generate mechanical noise. As customers have more and more stringent requirements for vehicle comfort, if the mechanical noise of the vehicle steering system components is not well controlled, it will cause customer complaints In severe cases, it may even affect customers' purchase choices of vehicle brands, leading to a decline in vehicle sales and affecting corporate profits

[0004] The worm gear and worm gear of the column type electric steering system are easy to produce mechanical noise. The mechanism of the noise mainly includes the following situations: 1. The processing of the parts of the worm gear and worm itself does not meet the design requirements, and the fit clearance does not meet the design requirements. ; 2. The axial coincidence degree of worm gear and worm is poor; 3. The surface of worm gear and worm is easy to wear and has burrs on the surface; 4. The grease applied between the worm gear and worm has poor performance and has not played its due role. lubrication

The detection of the above four mechanisms can be found through the worm gear of the reduction mechanism in conjunction with the change of the friction coefficient jump. If there is a problem, the friction system will have a relatively large jump, and even abnormal changes will occur.

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