Abstract:
A rack-and-pinion steering apparatus comprises pinion teeth formed according to proper tooth specifications in other aspects under a larger pressure angle, thereby stably offering smooth and comfortable steering feeling over a long time. The module (m), number of teeth (z), tooth depth (h) and helix angle (β) of the pinion teeth (4) are set within the following ranges, under a pressure angle (α) set within a range of 24° to 30° and a given stroke ratio. module (m): 1.8 to 2.0 number of teeth (z): 7 to 13 tooth depth (h): 2 m to 2.5 m helix angle (β): 35° or smaller
Abstract:
A rack-and-pinion type steering apparatus 1 includes a gear case 3 made of aluminum or an aluminum alloy and having a hollow portion 2; a steering shaft 6 rotatably supported by the gear case 3 through rolling bearings 4 and 5; a pinion 7 which is rotatably supported in the gear case 3 through the steering shaft 6; a rack bar 9 on which rack teeth 8 meshing with the pinion 7 are formed; and a rack guide 10 which is disposed in the hollow portion 2 inside the gear case 3 and supports the rack bar 9 slidably with respect to its moving direction A.