Self-generating elevator emergency power source

• US 6,516,922 B2
• Filed: 05/04/2001
• Issued: 02/11/2003
• Est. Priority Date: 05/04/2001
• Status: Expired due to Fees

• Current Assignee: Andrew Reisman, Gregory Shadkin
• Original Assignee: Andrew Reisman, Gregory Shadkin
• Inventors: Shadkin, Gregory, Reisman, Andrew
• Primary Examiner(s): SALATA, ANTHONY J
• Application Number:
  US09/849,030
• Publication Number:
  US 20020162705A1
• Time in Patent Office: 648 Days
• Field of Search: 187/290, 187/296, 187/404, 187/405, 318/375, 318/376
• US Class Current: 187/290
• CPC Class Codes: B66B 5/02 responsive to abnormal operating conditions
• CPC Class Codes: B66B 5/027 to permit passengers to leave an elevator car in case of failure, e.g. moving the car to a reference floor or unlocking the door

Abstract

An elevator system, elevator retrofit kit, and detachable counterweight for providing a self-generating elevator emergency power source. The system converts kinetic energy of an elevator cab descending due to gravity into electrical energy used to regulate the speed of descent. The elevator system can be structured in numerous ways and includes either a generator or a motor in generator mode, driven by a cable attached to the elevator cab and activated by the descent of the cab. The elevator cab descends due to gravity, either by using a counterweight being sufficiently light relative to the cab to cause the cab to descend, or by using a counterweight system whereby power loss or interruption causes the unlocking of a detachable counterweight from a permanent counterweight.

Claims

1. An emergency descent system for elevators using gravitational forces to control the descent of an elevator cab in the event of a loss of power from an outside power source, the system comprising:

a counterweight assembly including a counterweight weighing less than the minimum weight of the elevator cab;

a generating unit operatively coupled to a drive member and electrically coupled to a load bank;

a cable having a first end and second end, the cable operatively coupled to the drive member between the first end and second end, the first end coupled to the counterweight assembly and the second end coupled to the elevator cab such that the weight differential between the counterweight assembly and the elevator cab causes the drive member to rotate, causing the generating unit to produce a first generator torque and a corresponding first current; and

an elevator controller having a secondary power source to supply power to the elevator controller, the elevator controller electrically coupled to an outside power source, the secondary power source, the generating unit, and the load bank,

wherein the elevator controller configured to detect the speed of the elevator cab and direct a current from the generator to the load bank, and wherein the regulated current produces a generator torque to counteract the cab torque for controlling the rotation of the drive member and the descent of the elevator cab, and

wherein the counterweight assembly includes a constant counterweight weighing less than the minimum weight of the elevator cab, a detachable counterweight, and a releasable lock, the constant counterweight coupled to the first end of the cable and the detachable counterweight releasably coupled to the constant counterweight through the releasable lock, and wherein the elevator controller is electrically coupled to the releasable lock and is configured to send a release signal to the releasable lock upon a loss of outside power.

2. The emergency descent system of claim 1, further comprising a free-fall catcher connected to the detachable counterweight and configured for clamping to the counterweight rail upon a substantially free-fall descent.

3. The emergency descent system of claim 1, wherein upon the restoration of outside power, the elevator controller directs the elevator cab to rise and the constant counterweight to correspondingly lower into contact with the detachable counterweight, wherein the releasable lock is configured to couple the constant counterweight and the detachable counterweight.