| 摘要 |
There is provided a rack supporting device which comprises a supporting element (4) guided in the back and forth direction by the inner circumferential face of a guide hole (6) of a housing (3) and is made of a pair of half pieces (20, 21). The back face of the rack (2) is supported by the front ends of the half pieces (20, 21). Both half pieces (20, 21) are pressed to the back of the rack (2) and to the inner circumferential face of the guide hole (6). The inner circumferential face of the guide hole (6) is arranged on a first fictitious cylindrical face having an axis along the back and forth direction. The outer circumferential face of each of the half pieces (20, 21) has a small diameter portion (A, C) and a great diameter portion (B). The small diameter portion (A, C) is arranged on a second fictitious cylindrical face, which has an axis along the back and forth direction and the diameter of which is smaller than that of the first fictitious cylindrical face. The great diameter portion (B) is arranged on a third fictitious cylindrical face having an axis along the back and forth direction and the diameter of which is greater than that of the first fictitious cylindrical face. The outer circumferential face of each of the half pieces (20, 21) is in contact with the inner circumferential face of the guide hole (6) at both circumferential ends (P1, P2) of the great diameter portion (B). <IMAGE> <IMAGE> |
