Abstract: A castor wheel assembly on the underside of a shopping trolley comprises a wheel mounted to a wheel mount and rotatable about its rotational axis. A locking device including an engagement element and an actuator element is operatively coupled to the wheel mount for releasably engaging a locking element of the wheel mount to restrict swivelling of the wheel about a swivel axis of the wheel mount. The wheel is freely rotatable about the swivel axis when reversely rotated. Reverse rotation of the wheel urges the actuator element into pressing engagement with the wheel, driving the coupling portion of the engagement element away from the periphery of the wheel for disengagement of the engagement element from the locking element. Engagement of the engagement element and the locking element is only effected when the wheel is forwardly rotated to reduce the pressing engagement.

Abstract: The present invention relates generally to a castor wheel assembly 1 fitted onto the underside of the frame of a shopping trolley. The wheel assembly 1 comprises a wheel 2 mounted to a wheel mount 4 and rotatable about its rotational axis 6. Locking means in the form of an engagement element 8 and an actuator element 10 is operatively coupled to the wheel mount 4 for releasably engaging a locking element 12 of the wheel mount 4 to restrict swivelling of the wheel 2 about a swivel axis S of the wheel mount 4. The wheel 2 is substantially freely rotatable about the swivel axis S when the wheel 2 is rotated in the reverse direction. Rotation of the wheel 2 in the reverse direction urges the actuator element into pressing engagement with the wheel driving the coupling portion of the engagement element away from the peripheral surface of the wheel for disengagement of the engagement element from the locking element.