GB1428451A - Castors - Google Patents

Abstract

1428451 Castors BRITISH CASTORS Ltd 1 April 1974 [6 Jan 1973] 898/73 Heading A4U [Also in Division B7] A castor comprises wheels (13), 14 rotatably mounted on a body 10 and displaceable vertically relative to the body, and resilient means such as springs 22 biasing the wheels downwardly. The body 10 has a socket 11 in which is rotatably mounted a spindle 12 for attaching the castor to an article of furniture. The spindle may be retained in the socket 11 by a small projection formed in the socket 11 engaging a groove in the spindle. The wheels are inter-connected by interfitting spigots 17, 18 and the spigots may be fixed together or may be inter-connected by co-operating projection and recess means which permit relative rotation. The wheels are rotatably mounted on a carrier 19 which is slidably disposed in an opening 21 in the body 10 and which may be formed of two initially separate parts inserted into the opening 21 from opposite sides of the body and then secured together. Resilient buffers may be provided to limit vertical movement of the carrier 19. The springs 22 may be replaced by cylindrical blocks of rubber or other elastomeric material or by a leaf-spring. The carrier 19 may be replaced by a lever pivotally mounted on the body and biased downwardly by resilient means which may be a coiled spring, a leaf-spring, a block of elastomeric material or a torsion spring. A damper may be provided for damping movement of the carrier relative to the body and may be of the friction type or a fluid filled damper. In a modification, Fig. 4 (not shown), the spigots of the wheels are retained in assembled relation by a headed member received within a bore in the inner spigot and retained by a rib on the member engaging a recess in the bore and by co-operating splines on the member and in the bore. In a second modification, Fig. 5 (not shown), the wheels have spigots which are inter-connected directly but which are engaged over spigots projecting from the sides of the carrier. In a third modification, Fig. 6 (not shown), the carrier has a central bore having disposed in it an axle on opposite ends of which are rotatably mounted the wheels, and bearing sleeves are interposed between the bores of the wheels and the axle and are rotatable on the axle and are retained in the bores of the wheels by co-operating ribs and grooves. In another embodiment, Figs. 7 and 8 (not shown), the springs 22 are replaced by a single central spring. The carrier is inserted into the opening in the body from below, the opening extending to the bottom of the body and the carrier being retained by a member releasably closing the opening. The spring may be replaced by two springs in this embodiment, Fig. 10 (not shown). The carrier may be biased by two or more resilient elements arranged to provide a progressive rate of springing.