| 摘要 |
A method for producing the rack of variable ratio rack-and-pinion steering arrangements in which a uniformly toothed pinion meshes with a non-uniformly toothed rack. The rack has a central section (7) of uniform pitch and tooth shape flanked by two outer sections (8) having a different pitch and tooth shape so as to vary the steering ratio in dependence upon the position of the rack, the teeth in the transitional areas between the central section and the outer sections being of modified shape and pitch. The method comprises the steps of forming a rack with a central section (7) of uniform pitch and tooth shape, forming two outer sections (8) disposed one at a preset distance from each end of the central section (7) and having uniform pitch and tooth shape differing from the pitch and tooth shape of the central section, and producing transitional areas by form-grinding transitional tooth spaces (9, 10 and 9', 10') between the respective sections (7 and 8), which tooth spaces fan out from central points defined by the points of intersection (F and F1) of the helix angles of the last tooth spaces (A and A1 respectively) of the central section and the first tooth spaces (D and D1) of the respective outer sections (7 and 8). |
