Rack and pinion steering unit

Abstract

A rack and pinion steering gear unit is achieved that is capable of preventing an increase in operating force of the steering wheel and auxiliary operating force from a motor, and improving the response performance to minute operation when traveling straight. A pressing roller 34 elastically pushes the rear surface 29 of a rack shaft 9 toward a pinion shaft 5. This pressing roller 34 is supported by way of a radial needle bearing 16a by a support shaft 33 that is supported by and fastened to a holder 30 so as to be able to rotate freely. A thrust needle bearing 35 that receives a thrust load that is applied to the pressing roller 34 is provided between both side surfaces in the axial direction of the pressing roller 34 and the inside surface of the holder 30.

Description

technical field [0001] The present invention relates to a rack and pinion steering unit constituting a steering device for applying a steering angle to steering wheels of an automobile, and more particularly to a rack and pinion steering unit using a rolling rack guide. Background technique [0002] As a mechanism for converting rotational motion input from a steering wheel into linear motion for applying a steering angle, a rack and pinion steering unit is used. Steering devices equipped with rack and pinion steering gear units are described in Japanese Patent Application Laid-Open No. 2009-184591, Japanese Patent Laid-Open No. 2004-17872, Japanese Patent Application Laid-Open No. 61-124471, etc., and conventionally widely known. [0003] Figure 7 An example of a steering device incorporating a rack and pinion steering unit is shown. This steering device is a so-called column assist type rack and pinion power steering device. That is, in order to reduce the operating fo...

AI Technical Summary

Problems solved by technology

[0013] In this structure, since the inclined surface of the rack shaft is biased in the axial direction of the rack shaft, the rack shaft may be inclined with respect to the axis.

In addition, there may be manufacturing errors between the respective tapered surfaces of the pressing rollers divided into two, or gaps may occur between the inner peripheral surface of the pressing roller and the outer peripheral surface of the support shaft.

Therefore, in the case of this structure, due to the above-mentioned phenomenon, the meshing state of the meshing portion of the pinion teeth and the rack teeth cannot be properly maintained. sense of incongruity

If the meshing state of the meshing portion of the pinion teeth and the rack teeth deviates significantly from the proper state, damage, etc., may occur at the meshing portion due to a local collision.

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