Elevator apparatus

Patent metadata

Field	Value
Publication number	US-10093515-B2
Application number	US-201415122004-A
Country	US
Kind code	B2
Filing date	Apr 9, 2014
Priority date	Apr 9, 2014
Publication date	Oct 9, 2018
Grant date	Oct 9, 2018

Abstract

In an elevator apparatus, a safety device that makes a car perform emergency stopping is mounted to the car. A rope is installed in a loop inside a hoistway. The rope is connected to the car. A tensioning sheave around which the rope is wound is disposed in a lower portion of the hoistway. A tensioning sheave displacement detecting portion detects downward displacement of the tensioning sheave that accompanies dropping of the car due to breakage of the suspending body and activates the safety device.

First claim

The invention claimed is:

1. An elevator apparatus comprising:
a car that ascends and descends inside a hoistway;
a suspending body that suspends the car;
a hoisting machine that raises and lowers the car;
a safety device that is mounted to the car, and that makes the car perform emergency stopping;
a car buffer that alleviates mechanical shock from a collision of the car into a bottom portion of the hoistway;
a rope that is installed in a loop inside the hoistway, and that is connected to the car;
a tensioning sheave that is disposed in a lower portion of the hoistway, and around which the rope is wound; and
a tensioning sheave displacement detecting portion that detects displacement of the tensioning sheave that accompanies dropping of the car due to a breakage of the suspending body, and that activates the safety device.

2. The elevator apparatus according to claim 1 , further comprising a speed governor that includes a speed governor sheave, and that monitors for overspeed traveling of the car,
the rope being a speed governor rope that is wound around the speed governor sheave, and that is connected to the safety device.

3. The elevator apparatus according to claim 1 , wherein the tensioning sheave displacement detecting portion includes:
a rope gripping mechanism that is fixed inside the hoistway; and
a switch member that is connected to the tensioning sheave, the switch member is configured to be displaced downward and operate the rope gripping mechanism due to a downward displacement of the tensioning sheave,
wherein the rope gripping mechanism grips the rope to activate the safety device when the switch member is displaced downward.

4. The elevator apparatus according to claim 3 , wherein:
an expansion and contraction absorbing damper that absorbs vertical displacement of the tensioning sheave due to expansion and contraction of the speed governor rope by expanding and contracting is disposed between the switch member and the tensioning sheave; and
a switch member supporting spring that holds a position of the switch member relative to the rope gripping mechanism in opposition to expansion and contraction of the expansion and contraction absorbing damper is disposed between the switch member and the rope gripping mechanism.

5. The elevator apparatus according to claim 1 , wherein the tensioning sheave displacement detecting portion includes:
a signal generating portion that is activated by downward displacement of the tensioning sheave that accompanies dropping of the car due breakage of the suspending body to output an electrical activating command signal; and
an emergency safety activating portion that activates the safety device in response to the activating command signal from the signal generating portion.

6. The elevator apparatus according to claim 1 , wherein:
a hoisting machine brake is disposed on the hoisting machine; and
a vibration suppressing damper that suppresses vertical vibration of the tensioning sheave during emergency stopping of the car using the hoisting machine brake is connected to the tensioning sheave.

Assignees

• Mitsubishi Electric Corp

Inventors

• Shiraishi Naohiro
• Watanabe Seiji
• Fukui Kotaro

Classifications

• B66B5/0031

  for safety reasons · CPC title

• B66B5/28

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

• B66B9/00

  Kinds or types of lifts in, or associated with, buildings or other structures (characterised by control systems B66B1/00; apparatus for raising or lowering persons on stages of theatres A63J5/12) · CPC title

• B66B5/04

  for detecting excessive speed · CPC title

• B66B5/18

  and applying frictional retarding forces · CPC title