Method of Operating an Elevator System and Elevator System for the Method

Abstract

A method of operating an elevator system with a drum for taking up a suspension device, a drive unit for driving the drum, and a control unit for controlling the drive unit, includes operating the control unit of the drive unit to prescribe a rotational speed that depends on a length of the suspension device that is rolled onto the drum. Also included is an elevator system in which the method can be used.

Description

DESCRIPTION OF THE DRAWINGS

The above, as well as other, advantages of the present invention will become readily apparent to those skilled in the art from the following detailed description of a preferred embodiment when considered in the light of the accompanying drawings in which:

FIG. 1 is a perspective view of a prior art elevator system with a counterweight;

FIG. 2 is a perspective schematic representation of an elevator system with a drum to take up a suspension means according to the present invention; and

FIG. 3 is a schematic representation of an Archimedean spiral.

Claims

1. A method of operating an elevator system with a drum for taking up a suspension means, a drive unit for driving the drum, and a control unit for controlling the drive unit, comprising the steps of: a. generating from the control unit a signal representing a rotational speed that depends on a length of the suspension means that is rolled onto the drum; andb. operating the drive unit at the rotational speed in response to the signal.

2. The method according to claim 1 including determining the length of the suspension means that is rolled onto the drum from an absolute number of the turns of the drum.

3. The method according to claim 2 including determining absolute number of turns from a position of an elevator car attached to the suspension means in an elevator hoistway.

4. The method according to claim 1 including determining the length of the suspension means that is rolled onto the drum from a position of an elevator car attached to the suspension means in an elevator hoistway.

5. The method according to claim 1 including during commissioning of the elevator system initializing the control unit when the elevator car is moved into a starting position.

6. The method according to claim 1 performing said step a. after each turn of the drum.

7. The method according to claim 1 including rolling the suspension means onto the drum spirally.

8. An elevator system comprising: a drum for taking up a suspension means attached to an elevator car;a drive unit for driving said drum in rotation; anda control unit for controlling the rotation of said drive unit, said control unit operating to determine a rotational speed for said drive unit that depends on a length of said suspension means that is rolled onto said drum.

9. The elevator system according to claim 8 including a value encoder connected to said drive unit for determining a number of turns of said drum.

10. The elevator system according to claim 9 wherein said value encoder is an absolute value encoder.

11. The elevator system according to claim 8 including a value encoder attached to the elevator car for determining a position of the elevator car.

12. The elevator system according to claim 11 wherein said value encoder is an absolute value encoder.