The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 19, 1999
Filed:
Mar. 17, 1998
Gerard G Piserchia, Emerson, NJ (US);
Julio C Ramos, Lake Hiawatha, NJ (US);
Inventio AG, Hergiswil NW, CH;
Abstract
An emergency stop circuit for an elevator drive includes an emergency stop control (7) that selectively varies the current flowing in a field winding (4) of a direct current drive motor (M). During an emergency stop, the motor (M) operates as a generator and has an armature winding (1) loaded with a braking resistor (9) to apply a voltage, depending on the direction of movement of the elevator car, either by a first switch (10) and a second switch (11), or by a third switch (12) and a fourth switch (13). The switches (10, 11, 12, 13) are connected as an H-bridge between the windings (1, 4) and are controlled by the emergency stop control (7) depending on the deceleration required by the elevator car, for example by pulse operation depending based upon a preset deceleration value and a measured deceleration value from a deceleration sensor (14) mounted on the car.