Abstract: A lock for a sliding door has at least one locking bolt adapted in use to be moved between an open position and a locking position by activation of an operating member which rotates a pinion which engages a pair of drive racks to cause movement of the locking bolt generally parallel to the longitudinal axis of the bolt and in a direction parallel to a leading edge of a door in which the lock is mounted. The locking bolt is adapted when moved to its locking position to move into locking engagement with a staple-like keep mounted on a frame for the door when the door is in a closed position. A key operated deadlock facility prevents activation of the operating member. Preferably, the lock is also fitted with a safety mechanism so that it cannot be damaged if the door to which it is fitted is closed when the lock is in a locking position, and it is also possible to provide both an automatic latching and a panic feature on the lock.

Abstract: The invention provides a wheel or roller assembly for a patio door or the like comprising a carriage having two parallel spaced side plates, and a wheel rotatably mounted within the carriage by means of a pair of spaced ball- or roller-bearing sets, one at or adjacent each side thereof.In a preferred embodiment, the inner and outer races of a pair of ball bearing sets are provided by inturned arcuate portions of the side plates and interior edge regions, for example lined arcuate grooves, of the wheel respectively.