Abstract: An improvement in a sealing combination for sealing intermediate a cap ring on the hydraulic cylinder or the like and a rod running concentrically therethrough characterized by, in addition to the usual cage assembly on the cylinder assembly, a stuffing box and a wiper ring box for holding respective seals and ring wiper, bearing for maintaining the rod centralized within the central assembly and facilitating longitudinal movement, primary seal disposed about the rod and within the sealing box, a rod wiper disposed about the rod and within the wiper ring box, secondary seal disposed about the rod and intermediate the primary seal and the rod wiper and stop device disposed intermediate the primary seal and the secondary seal and adapted to stop longitudinal movement of the bearing to prevent crushing the second seal. Also disclosed are specific preferred embodiments.

Abstract: An elevator car has a drive mechanism mounted in a compact housing on the upper surface of the car. The drive mechanism includes a rotatable drive shaft, around which is mounted a linear actuator block having a plurality of ball bearings, obliquely arranged relative to the shaft, and firmly touching the shaft. Rotation of the shaft by a motor makes the block move linearly along the shaft. A bracket attached to the block carries an elevator door. Rotation of the shaft therefore opens and closes the door. The direction of movement of the block, and hence the door, depends on the direction of rotation of the shaft. The drive mechanism is compact and simple, and can be applied to new elevators or can be used to retrofit existing elevator cars.