| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress a decrease in braking force due to axial deformation of an annular flange without causing any increase in weight of a screw shaft. <P>SOLUTION: A normal and parking brake device 100 includes a cylinder 11, a piston 21 assembled in an in-cyclinder hole 11a of the cylinder 11, and a brake lining 31a pressed by the piston 21 against a braked rotary body (40), and also includes a nut member 61 and a screw shaft 62 which are connected to each other by screwing and an electric motor 71 capable of driving them. The screw shaft 62 has a rotary shaft part 62b in one side region, a male screw part 62b in the other end region, and an annular flange 62c in an intermediate region. At the annular flange 62c, a tapered engagement surface Sa is formed which faces the bottom wall surface 11b2 of the cylinder 11 while making the external diameter of the rotary shaft part 62a small and the external diameter of the annular flange 62c large, and a tapered bearing surface Sb which bears the engagement surface Sa rotatably is formed on the bottom wall surface 11b2 of the cylinder 11. <P>COPYRIGHT: (C)2013,JPO&INPIT |
