Elevator with adjustable buffer length

Patent metadata

Field	Value
Publication number	US-9517919-B2
Application number	US-201514716530-A
Country	US
Kind code	B2
Filing date	May 19, 2015
Priority date	Nov 20, 2012
Publication date	Dec 13, 2016
Grant date	Dec 13, 2016

Abstract

An elevator includes at least one elevator car driving along an elevator shaft as well as an elevator control measuring the car position. The elevator further includes a buffer in the shaft pit, whose length is adjustable in response to the car position and car speed. Via this measure, the shaft pit can be reduced in high speed elevator requiring large buffer lengths.

First claim

The invention claimed is:

1. An elevator comprising:
at least one elevator car driving in an elevator shaft;
an elevator control measuring the car position; and
a buffer in a shaft pit of the elevator shaft,
whereby a length of the buffer is adjustable in response to the car position,
wherein the elevator control has a buffer control part which is configured to monitor the deceleration of the elevator car when approaching the lowest landing in the elevator shaft, and wherein the buffer control part is configured to decrease the buffer length if the car deceleration during approach to the lowest landing corresponds to a given slope.

2. The elevator according to claim 1 , wherein the shaft pit has a smaller depth below the lowermost landing than a maximal length of the buffer.

3. The elevator according to claim 1 , wherein the buffer is a hydraulic cylinder device having a cylinder and a piston, wherein a position of the piston with respect to the cylinder is adjustable.

4. The elevator according to claim 1 , wherein control car position detectors are provided at different levels in the elevator shaft in a car deceleration zone above the lowest landing, which position detectors co-act with a triggering element mounted at the elevator car, wherein a reference data memory is provided in connection with the elevator control and wherein the buffer control part is configured to issue a fault action when actual car speed at the level of a position detector exceeds a corresponding reference speed from the reference data memory by a limit value.

5. The elevator according to claim 4 , wherein the control car position detectors are provided additionally to an obligatory car position measuring device of the elevator.

6. The elevator according to claim 4 , wherein the fault action comprises the opening of an elevator safety circuit.

7. The elevator according to claim 4 , wherein the fault action comprises the activation of a buffer drive to extend the buffer length.

8. A method for adjusting the length of a buffer in the shaft pit of an elevator shaft, said method comprising the steps of:
determining the position of an elevator car; and
adjusting the length of the buffer in response to the actual car position,
wherein the buffer length is reduced when the elevator car approaches the lowest landing and decelerates according to a given deceleration slope.

9. The method according to claim 8 , wherein the buffer is extended to its maximum length if the elevator car deviates by a limit extent from the given deceleration slope when approaching the lowermost landing.

10. The method according to claim 8 , wherein the signal of position detectors in the car deceleration zone of the elevator shaft above the lowest landing is used as trigger for the elevator control to compare the actual car speed with a reference car speed corresponding to the location of the position detectors and wherein a fault action is provided if the actual car speed at said locations exceeds the reference value by a limit value.

11. The method according to claim 10 , wherein the fault action comprises the driving of the buffer length to its maximal value and/or the opening of an elevator safety circuit.

12. The elevator according to claim 2 , wherein the buffer is a hydraulic cylinder device having a cylinder and a piston, wherein a position of the piston with respect to the cylinder is adjustable.

13. The elevator according to claim 5 , wherein the fault action comprises the opening of an elevator safety circuit.

14. The elevator according to claim 5 , wherein the fault action comprises the activation of a buffer drive to extend the buffer length.

15. The elevator according to claim 6 , wherein the fault action comprises the activation of a buffer drive to extend the buffer length.

16. The method according to claim 8 , wherein the buffer is extended to its maximum length if the elevator car deviates by a limit extent from the given deceleration slope when approaching the lowermost landing.

17. The elevator according to claim 1 , wherein the length of the buffer is adjustable in response to the car speed.

18. The method according to claim 8 , further comprising the steps of:
determining the speed of the elevator car; and
adjusting the length of the buffer in response to the actual car speed.

Assignees

• Kone Corp

Inventors

• Kalliomäki Jaakko
• Puranen Mikko

Classifications

• B66B5/28 Primary

  Buffer-stops for cars, cages, or skips · CPC title

• B66B5/282

  Structure thereof · CPC title

• B66B5/16

  Braking or catch devices operating between cars, cages, or skips and fixed guide elements or surfaces in hoistway or well · CPC title

• B66B5/06

  electrical · CPC title