US 5,494,133 AGranted

Controlled weight-lowering device

AssigneeKenneth Green

InventorsKenneth Green, Ewald Kerkhoff, David Call

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Abstract

A controlled weight-lowering device is presented which allows an individual to descend from a building at a predetermined rate of descent. The device can be permanently attached to the building or it can be portable. The device has an outer bracket which is securely attached to the inside of the building. Rotating about a shaft attached to the bracket is a cylindrical winding drum. The drum has a rope wound around it that is attached to a harness. The individual puts on the harness he desires to descend. Inside the winding drum is an inner gear pump and valve mechanism which is surrounded by an oil reservoir. Oil is allowed to go into the gear set chamber and circulates past the gears. The rate of flow of the oil out of the gear set chamber is regulated by a spring biased tapered piston. As the strength of the spring biasing is set on the piston, the rate of flow of oil within the gear set chamber is regulated. Because the gear set is connected to the cylindrical axis of the winding drum, controlling the rate of flow of oil, which controls the rate of rotation of the gears, also controls the rate of rotation of the drum.

Claims7

Dependent claims

A controlled weight lowering device for lowering human beings or other objects, comprising:

(a) an outer attaching bracket which supports a rotating drum, said drum rotating about a keyed shaft attached to said bracket;
(b) said drum having a rope wound about its circumference and containing an inner controlling mechanism;
(c) said controlling mechanism comprising:
(1) a gear chamber having a pair of rotating intermeshed gears wherein the teeth of said gears have very close tolerances whereby oil within said gear chamber cannot flow between said gear teeth and wherein one of said gears is connected to said rotating keyed shaft, said gear chamber having a plurality of inlet ports and one cylindrical outlet port;
(2) an oil reservoir surrounding said gear chamber wherein oil from said reservoir circulates into said gear chamber through said inlet ports;
(3) a tapered piston for controlling the rate of flow of oil out of said gear chamber through said outlet port, said piston being biased closed towards said cylindrical outlet port by a disc-spring, wherein said disc-spring may be pre-set to open said outlet port when a pre-determined rotational force is applied to said drum and wherein said disc-spring may be adjusted while said lowering device is in use to regulate the rate of descent of said human or object.

3 more elements

Dependencies are inferred from the claim text.