Patent ID: 9211762
Filing Date: 2015-12-15
Classification: B60B

Abstract:
1. A castor comprising: a castor body provided with an upright shaft swivelly mounted thereto, an upper slideway, a lower slideway and a projection; a gear connected with the upright shaft of the castor body; two rollers rotatably mounted on two opposite sides of the castor body; a first braking member pivotally connected with the castor body and provided with a protrusion; a second braking member slidably mounted in the lower slideway of the castor body and being engageable with the gear; a sliding block slidably mounted in the upper slideway of the castor body; a compression spring mounted in the upper slideway of the castor body and 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; wherein: each of the rollers has an inner face provided with a plurality of locking grooves; the first braking member has an upper end provided with a press portion abutting the sliding block and a lower end provided with a push portion abutting the second braking member; the second braking member has an outer end connected with the push portion of the first braking member and an inner end engageable with the gear; and the sliding block is provided with a plurality of locking pieces for locking in the locking grooves of each of the rollers.