Abstract: An elevator includes a special propelling fluid dynamic device which uses as a plunger the duly balanced car counterweight. The car conveys people and things upwards and downwards within a vertical conduit or hoistway supported by a cable extending to an upper pulley. When changing the direction, a counterweight is extended to balance the car. The pulley is supported from the hoistway walls and is kept in a freely-rotating condition while the balanced counterweight is a hollow piston-counterweight, accommodated in the cylinder vertically disposed in the hoistway itself and adjacent to the car. Both are integral with the propelling fluid dynamic device that produces the upward and downward movements of the car, which is completed with a circuit having a fluid flow conduit and a driving pump coupled to the valve mechanism.

Abstract: An elevator includes a special propelling fluid dynamic device which uses as a plunger the duly balanced car counterweight. The car conveys people and things upwards and downwards within a vertical conduit or hoistway supported by a cable extending to an upper pulley. When changing the direction, a counterweight is extended to balance the car. The pulley is supported from the hoistway walls and is kept in a freely-rotating condition while the balanced counterweight is a hollow piston-counterweight, accommodated in the cylinder vertically disposed in the hoistway itself and adjacent to the car. Both are integral with the propelling fluid dynamic device that produces the upward and downward movements of the car, which is completed with a circuit having a fluid flow conduit and a driving pump coupled to the valve mechanism.