GB1347459A - Caster wheel - Google Patents

Abstract

1347459 Castors HUFA-ROLLEN HUGO FASSBENDER K G 26 May 1972 [31 July 1971] 25030/72 Heading A4U [Also in Division F2] A castor assembly includes a steering lock 26 by which a wheel 3 is locked in a straight line of travel by the engagement of a tang 33 on a locking lever 32 in a notch 34 in a fork base plate 5. The locking lever 32 is loaded by a spring 35 and is pivoted on a lock support plate 38 on which is also pivoted an actuating lever 27 by which the locking lever is released, each lever being retained in locked and unlocked positions by an over-centre device. Pivot pins 30, 39 of the levers 27, 32 have bearings in side webs of the support-plate 38, which is secured to a base plate 9 of the assembly, the spring 35 being mounted on the pin 39 and having upper and lower arms bearing on the support plate 38 and on a lateral part 42 at the tanged end of the locking lever 32. An actuator bar 31 extending between side webs 28 of the actuating lever 27 bears against the locking lever so that in unlocked position, Fig. 1, in which the locking lever forms an approximately horizontal extension of the support plate 38, the inner end of the lever 27 is held by the spring 35 in engagement with the face 38" of the plate 38. When the actuating lever is depressed the bar 31 moves through a relatively small angle α, past a dead-centre line X-X and through a larger angle # into its locked position, the thrust of the spring snapping the locking lever 32 into its locked position in which edges 45 of walls 28 contact edges 46 of the locking lever or the tang 33 abuts the upper surface of a spring 19 secured to the base plate 5. The spring 19 has a lower part with a projection 20, adjustable by a screw 21, and an upper part having teeth 18, the projection 20 engaging the periphery of the wheel, to prevent rolling movement of the wheel 3, and the teeth 18 engaging recesses 17' in a plate 17, welded to the lower end of a plunger 13, which is vertically and non-rotatably movable in a bush 11 welded to the base plate 9, to prevent swivelling of the castor when the plunger is depressed, against the action of spring 25, by pressure on a head 14. In a modification, side webs of the locking lever support a pivot pin for the actuating lever which is urged by a single-arm spring to bear, in the unlocked position, by an intermediate part on an edge of the lock support plate and by an upturned inner end on the under surface of the lock support plate. In the depressed, locked position of the actuating lever the edges of the side webs thereof bear on the undersurface of the lock support plate.