RU179811U1 - MAGNETIC BRAKE - Google Patents

Abstract

The utility model belongs to the class of devices that ensure the safe operation of lifting devices when an abnormal speed (acceleration) occurs due to braking effects created by the interaction of permanent magnets with eddy currents induced in a metal guide rail. The technical result of the application of the proposed magnetic brake is to ensure the safe movement of the cabin of the lifting devices, including elevators, when creating abnormal (emergency) traffic conditions. The magnetic brake of the elevator car or other lifting device is based on the braking effect of the interaction of permanent magnets assembled in cages on the outside cabs with alternating magnetic poles, in eddy currents induced in a metal bus (guide) when they move relative to each other. The force of (non-contact) braking is regulated by changing the gap between the planes of the magnets and the guide, due to the support rollers built into the cage with magnets. When creating an emergency (emergency) situation and increasing the speed of the cab, the magnetic brake automatically ensures the normal descent speed. 3 ill.

Description

The proposed device relates to a means of ensuring the safe operation of elevators and other lifted and lowered along metal guiding objects. Various types of mechanical and electromechanical devices are known that inhibit or catch an elevator car falling in an emergency. A common drawback for these devices, including spring-loaded and powered by electricity, is not a complete guarantee of the safety of the elevator cabs, especially when the power is turned off.

These drawbacks are deprived of permanent magnet brakes interacting with a metal guide (bus) fixed in the elevator shaft. By creating eddy currents in the latter, moving by permanent magnets fixed on the elevator car, contactless braking of the car is ensured, which does not allow it to move down with acceleration.

A device [1] is known with permanent magnets fixed to a vehicle (attraction cabin) and a tire with plates of various materials fixed to it to provide the necessary braking force on a known section (for the attraction — of the final) tire. The proposed solution is designed to perform tires of heterogeneous material in the braking area, which reduces the braking efficiency.

The magnetic brake proposed in [2] is characterized by greater braking efficiency due to the performance of tire parts from various metals, which increase the braking effect, but only in the final section of the vehicle. However, for an elevator circuit (non-attraction), where the section of the start of braking (in an emergency) can be on any part of the tire, the manufacture of its individual sections from various materials does not make sense, since braking must occur at any moment of an abnormal increase in the speed of the elevator car.

The technical problem of the utility model to be solved is to ensure the safe descent of the elevator car from any moment when the nominal speed exceeds 2-3 times during an emergency at any height of the elevator shaft. In this case, the safe braking system should not consume any energy.

The solution to this problem is achieved by using a magnetic brake of the elevator car, containing a metal guide rail installed in the elevator shaft and permanent magnets mounted on the elevator car and covering the bus from opposite sides with opposite magnetic poles, characterized in that the magnets are assembled in cages (with alternating magnetic poles), which are attached to the cab and rest on the bus through adjustable rollers, providing a constant clearance that does not affect the regular movement of the cab, but limiting it to orost to the nominal descent speed in an emergency situation.

The advantages of the proposed utility model over the known analogues and prototype are as follows:

- provides the effect of emergency braking on any part of the tire from any moment exceeding the nominal speed of the cab;

- provides a greater braking effect (braking force), due to the location of the permanent magnets in the clips with the alternation of their magnetic poles;

- eliminates the friction of the permanent magnets on the metal guide rail by installing rollers between it and the clips;

- it is possible to smoothly change the gap between the metal guide rail and the clips by adjusting the rollers when setting up the device.

Thus, the foregoing features are novel, essential and provide the device with industrial applicability, because allow:

- to ensure the operation of the magnetic brake on any part of the metal guide rail, which extends the working range of its application along the entire shaft;

- change the braking force by changing the clearance between the metal guide rail and the clips using adjustable rollers;

- apply a metal guide rail made of homogeneous metal;

- to increase the service life of the device due to the absence of wear from friction of permanent magnets on a metal guide rail.

In the drawings (Fig. 1, Fig. 2 and Fig. 3), the proposed magnetic brake is shown in schematic form. In FIG. 1, an elevator car 1 is shown moving along two metal guide rails installed in the shaft opposite each other 2. Brackets 3 with clips 4 are mounted on the cab 1, including permanent magnets 5 on both sides with defined clearances, covering the metal guide rails 2. At the ends holders 4 (Fig. 2, section A-A), rollers 6 are mounted, resting on a metal guide rail 2 with the possibility of adjusting the gap between the permanent magnets 5 in the ferrule 4 and the metal guide rail 2.

Permanent magnets 5 in the clips 4 are arranged with alternating magnetic poles and so that the metal guide rail 2 is enclosed by opposite poles on both sides of them. The rollers 6 (Fig. 3, section B-B) using the regulators 7, set the gap between the permanent magnets 5 and the metal guide rail 2, so as to provide the necessary braking force of the cab 1 when the standard speed of its movement is exceeded.

Features of the proposed magnetic brake are:

- the constant availability of the emergency response device anywhere in the elevator shaft and ensuring a safe lowering speed;

- manufacturability and ease of manufacture of a metal guide rail from a homogeneous metal, including steel;

- the ability to achieve the necessary braking force as the number of clips, the magnitude of the magnetic induction of permanent magnets, and the size of the adjustable clearance between the clips and the metal guide rail;

- elimination of the friction of the permanent magnets on the metal guide rail due to the rollers.

During the movement of the elevator car in an emergency (breakage of all cables, etc.), its speed increases sharply. Accordingly, the speed of movement of permanent magnets fixed on the cab relative to the metal guide rail increases, which generates strong eddy currents in it, which, when interacting with the magnetic field of the permanent magnets, create braking forces that stabilize the movement of the cab with a constant safe descent speed. The selection of the number and physical parameters of permanent magnets and the gap between the clips and the metal guide rail provides the necessary safe speed for lowering the cab in an emergency.

The features presented in the proposed utility model, together with the features of the prototype, are essential and solve the technical task of ensuring the safe speed of the elevator car in an emergency.

In general, the proposed utility model has novelty, a high technical level and industrial applicability and, according to the applicants, can be protected by a patent of the Russian Federation.

Information sources:

1. US patent 60623350, IPC B60L 7/28 from 05.16.2002

2. Patent No. RU 2205113, IPC B60L 7/28 of July 15, 2002 (Prototype of the invention).

Claims (1)

Magnetic brake of the elevator car, comprising a metal guide rail installed in the elevator shaft, and permanent magnets mounted on the elevator car and covering the bus on both sides with opposite magnetic poles, characterized in that the magnets are assembled with alternating poles in clips that are attached to the car and they rely on the tire through adjustable rollers, providing a constant clearance that does not affect the speed of the cab during regular movement, but prevents its acceleration in emergency situations to a constant standard soon STI lift.

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