摘要 |
A castor includes a castor body provided with an upper slideway, a lower slideway and a projection, two rollers mounted on the castor body, a first braking member pivotally connected with the castor body and provided with a protrusion, a second braking member mounted in the lower slideway, a sliding block mounted in the upper slideway of the castor body, a compression spring biased between the castor body and the sliding block, and a linear spring mounted between the projection of the castor body and the protrusion of the first braking member. Thus, the linear spring provides a restoring force to the protrusion of the first braking member and eliminates the stress applied on the protrusion of the first braking member and the projection of the castor body. |