Patent · US Expired

Elevator speed control

US4527662A · kind A · utility

7Cited by
5References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 1, 1983
Grant dateJul 9, 1985
Priority date
Expiry dateApr 1, 2003

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB66B1/285
  • WIPO fieldHandling
  • WIPO sectorMechanical engineering

Abstract

To control an elevator motor, a first analog signal, the profile of which defines the velocity characteristics during acceleration, is generated in response to a motor jerk signal, a signal to accelerate the motor. This first analog signal is then multiplied with a second analog signal to provide a third analog signal which is supplied to the motor controls. The magnitude and polarity of that third analog signal controls motor speed and direction. The second analog signal has a unity value, a value of one, except when the car is within a slowdown distance from the floor. When the car moves through that range, the second analog signal decreases from unity. The second analog signal is provided from digital coefficients that are stored in a memory device and addressable for particular positions from the slowdown position. The coefficients are addressed by the output from a down counter that counts pulses that are provided by a car position transducer as the car moves from the slowdown position. The relationship between the counts and the stored digital coefficients which they address define the deceleration profile.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.