elevator safety system

Abstract

The invention provides a safety system of an elevator; the system can detect overspeed of an elevator car in a whole elevating passage area, so the speed of the elevator car can be reduced in a possible early time; the safety system of the elevator can detect a car speed matched with the car position, when the car speed exceeds an allowed speed, the elevator is determined to have overspeed, and the motion of the elevator car is limited; the safety system comprises the following structures: a plurality of detection plates arranged on specific positions; a car position sensor arranged on the elevator car and used for detecting the detection plates; a safety controller determining whether the car position is in a specific position or not according to the output of the car position sensor; a position and speed linked information database used for storing distance information indicating the specific position and interval of the detection plates; the safety controller can calculate car speed of each interval according to passing time and distance information of each interval; the calculated car speed matched with the car position is compared with an overspeed determining curve, and overspeed condition happens or not can be determined.

Description

technical field [0001] The present invention relates to a safety system of an elevator whose safety is ensured by a safety device arranged in an elevator passage. Background technique [0002] In the safety device of the existing elevator system, a forced deceleration device for the terminal floor is provided. Safety is ensured by setting the buffer at the lower part of the elevator passage below the allowable collision speed. [0003] In high-speed elevators, if it is necessary to install buffers that allow collisions at rated speeds, the length of the buffers will become very long, requiring excavation of elevator pits tens of meters deep. The purpose of the forced deceleration device on the terminal floor is to reduce the depth of the elevator pit, and it is mainly used for elevators with long strokes. [0004] As a terminal floor forced deceleration device, for example, Patent Document 1 discloses a device that, in order to detect the speed of the car, uses an approach...

AI Technical Summary

Problems solved by technology

[0010] In the above-mentioned prior art, when the elevator temporarily stops or accelerates suddenly in the overspeed detection area, the calculated car speed may be lower or higher than the actual speed when the elevator leaves the overspeed detection area. Apparent speed, so it is possible to make a wrong judgment

In addition, in Patent Document 2, a cam and an encoder are used for position detection and speed detection, and when a sensor fails, the elevator system needs to be stopped, resulting in a decrease in the operating rate of the elevator system.

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