Patent ID: 9656685
Date: 2017-05-23
CPC Classifications: B62D,F16B,F16C,F16H,F16J,Y10T

Claim:
1. A rack and pinion steering gear unit comprising: a casing having a cylindrical shaped main housing section that is open on both ends, and a cylindrical shaped sub housing section that is open on one end and is provided in a twisted position with respect to the main housing section; a rack shaft having rack teeth on a front surface thereof, and is located on an inside of the main housing section of the casing so as to be able to displace in an axial direction thereof; a pinion shaft having pinion teeth that are formed on a tip half section in an axial direction thereof and that engage with the rack teeth, and with a base end section in an axial direction thereof protruding to an outside through an opening section of the sub housing section of the casing, is supported inside the sub housing section so at to be able to rotate freely; a rolling bearing comprising an inner ring having an inner raceway around an outer circumferential surface thereof, an outer ring having an outer raceway around an inner circumferential surface thereof, and a plurality of rolling bodies that are provided between the inner raceway and outer raceway so as to be able to roll freely; and in order to support the pinion shaft inside the sub housing section, the inner ring is fastened around a portion of the pinion shaft that is closer to the base end section side in the axial direction than a portion where the pinion teeth are formed, and with one side surface in the axial direction of the outer ring being in contact with a stepped surface that is formed around the inner circumferential surface of the sub housing section, the outer ring is fitted inside and supported to the sub housing section; a C-shaped incomplete circular ring shaped retaining ring that is located around a middle section in the axial direction of the pinion shaft, that is provided with a non-continuous area, and that, with a radially outside portion thereof fastened to a fastening groove that is formed around the inner circumferential surface near the opening section of the sub housing section, presses one side surface in the axial direction of a radially inside portion thereof against other side surface in the axial direction of the outer ring so as to apply a preload to the ball bearing; and a diameter reduction prevention section that is provided on part of a member that is fastened to an opening side end section or a section near the opening section of the sub housing section, and by being inserted inside the non-continuous area of the retaining ring and engaging with the retaining ring, prevents reduction of the diameter of the retaining ring, wherein the non-continuous area of the retaining ring is located on a rack shaft side of the retaining ring, a clip that comprises a radially outside arm section and a radially inside arm section is elastically mounted to an opening side end section of the sub housing section so as to span the opening side end section, and the diameter reduction prevention section is constructed by a tip-end section of the radially inside arm section that is placed inside of the sub housing section, and a stopper structure for preventing the clip from coming out from the opening side end section of the sub housing section is provided between the clip and the sub housing section on an outer circumferential surface side of the opening side end section of the sub housing section.