JPS5833419B2 - electromagnetic braking device - Google Patents

Abstract

PURPOSE:To have a stable and smooth performance of a depressing rod in an electromagnetic braking device equipped with a plunger type electric magnet by fixing a moving core and the depressing rod independently on the stationary core. CONSTITUTION:A depressing rod 12 for a brake is born inside a stationary core 11 with two bearings 13, 16. A moving core 17 is formed independently from the depressing rod 12 and so arranged as in sliding contact with a bushing 22. When current is applied to a coil 10, a force is applied to the moving core 17 which wants to move it, not only in the axial but also normal direction, where the moving core 17 and depressing rod 12 are in contact with each other while being born independently, so that only the axial directed motive force of the moving core 17 is transmitted to the depressing rod 12.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electromagnetic braking device, and particularly to an electromagnetic braking device equipped with a plunger type electromagnet suitable for use in an elevator.

FIG. 1 is a diagram showing a schematic configuration of a conventional electromagnetic moving device for elevators of this type.

The braking device has a structure in which a pair of levers 5 embrace a brake drum 1 from the outside, and a brake lining 7 that contacts the outer peripheral surface of the brake drum 1 is fixed to the inside of the levers 5 via a brake pad. ing.

A brake spring 2 is attached to the upper part of the pair of levers 5.
The pressure of this braking spring 2 is applied to the lever 5, the brake juro,
The braking force is transmitted to the outer peripheral surface of the brake drum 1 via the brake lining 7, and the braking force is applied to the brake drum 1.

Further, an electromagnet 30 is provided at the upper part of the brake drum held between the brake springs 2 by the lever 5, and the push-down rod 12 of the electromagnet 30 pushes down the arm 4 fixed to the push rod 3. The braking force is released.

FIG. 2 shows a conventional example of the electromagnet 30 shown in FIG.

A fixed iron core 11 having a through hole in the center is arranged concentrically inside the cylindrical yoke 9, and the fixed iron core 11 is fitted and fixed to the lower surface of the yoke 9.

A bearing 13 is inserted into the lower end of the through hole of the fixed core 11, and a shaft (push rod 12) fixed to the movable core 15 supported by the bearing 13 is inserted into the through hole of the fixed core 110. .

An end plate 8 forming a magnetic circuit is fixed to the outer peripheral portion of the movable iron core 15 via a predetermined gap to the upper end opening of the yoke 9.

Further, a bracket 21 made of a non-magnetic material is fitted and fixed concentrically with the yoke 9 on the upper part of the end plate 8.

A bearing 14 is inserted into the center of the bracket 21, and the other end of the push-down rod 12 of the movable iron core 15 is supported by the bearing 14.

Furthermore, a cylindrical coil bobbin 20 is installed concentrically between the lower end of the end plate 8 and the lower surface of the yoke 9, and an excitation coil 10 is wound around the outer periphery of the coil bobbin 20. There is.

The push-down rod 12 of the movable iron core 15 is slidably attached to the bearing 1.
3 and 14, and the movable iron core 15 can move up and down.

When the brake is released, when the excitation coil 10 is energized, the fixed iron core 1
1 is magnetized, the movable iron core 15 is attracted to the fixed iron core 11, and the push-down rod 12 of the movable iron core 15 protrudes.

However, in the structure of such a conventional electromagnetic braking device, the movable core 15 is caused by the eccentricity of the yoke 9 and the end plate 8, which are located on the outer circumference of the movable core 15 with a gap between them.
A biased magnetic force acts on the

This biased magnetic force causes the push-down rod 1 of the movable iron core 15 to
2 and the bearings 13, 14 in a direction perpendicular to the axial direction, a drawback arises in that the inner surface of the bearing material is worn out.

Moreover, due to this wear, the movement of the movable iron core 15 in the axial direction and the perpendicular direction during suction is increased more than a specified value, resulting in a drawback that the suction operation of the movable iron core 15 is inhibited.

An object of the present invention is to provide an electromagnetic braking device that eliminates the above-mentioned drawbacks, stabilizes and smoothes the movement of the push-down rod associated with the suction operation of the movable iron core, and reduces wear on the bearing section that supports the push-down rod. It is about providing.

The present invention includes a fixed iron core fixed to a yoke equipped with an excitation coil, and a rod-shaped push-down rod that is slidably supported by a bearing provided in a through hole of the fixed iron core and that extends through the through hole. and a movable core that is disposed opposite to the fixed core and moves toward and away from the fixed core, and the movable core and the end of the pushing/lowering rod are brought into contact with each other so that they are not connected and fixed to each other. It is equipped with an electromagnet.

An embodiment of the electromagnetic braking device of the present invention will be described below with reference to FIG. 3, using the same reference numerals for the same parts as those of the conventional example.

FIG. 3 is a longitudinal sectional view showing the structure of an electromagnet, which is a main part of this embodiment.

Inside the cylindrical yoke 9, a coil bobbin 20 around which an excitation coil 10 is wound is arranged concentrically.

A fixed iron core 11 having a through hole in the center is arranged concentrically inside the coil bobbin 20, and the fixed iron core 11 is fitted and fixed to the lower surface of the yoke 9.

A bearing 13 and a bearing 16 are provided at both ends of the fixed core 110 through hole.
are fitted, and the fixed core 11 is fixed by these bearings 13 and 16.
A push-down rod 12 inserted into the zero through hole is supported.

A movable core 17 is disposed above the fixed core 11 to face it, and the lower surface of the movable core 17 is in contact with the end of the push-down rod 12 .

The outer peripheral surface of the movable iron core 17 is in sliding contact with a bushing 22 made of a non-magnetic material, and this bushing 22 is supported by a case 19 forming a magnetic circuit.

Furthermore, this case 19 is fixed to the upper end opening of the yoke 9, and the upper opening of the case 19 is covered with a cover 18.

Note that when the pressure of the brake spring 2 is applied to the drum (not shown) via the lever 5, the gap between the fixed iron core 11 and the movable iron core 17 is G.

The rest of the configuration is the same as the conventional example shown in FIG. 1, so the explanation will be omitted.

Next, to explain the operation of this embodiment, the excitation coil 1
0, the fixed iron core 11 is magnetized and the movable iron core 1
7 is attracted to the fixed iron core 11.

Then, the push-down rod 12 protrudes and pushes the arm 4,
The braking force exerted by the braking spring 2 is released.

At this time, even if a biased magnetic force is generated due to the eccentricity of the yoke 9, case 19, etc. that form the magnetic circuit, the force generated by this biased magnetic force to move the movable iron core 17 in the direction perpendicular to the axial direction is 12 and the movable iron core 17 are only in contact with each other, the force is not transmitted to the push-down rod 12.

That is, only the axial motion force of the movable iron core 17 is transmitted to the push-down rod 12.

According to this embodiment, the movable iron core 17 and the push-down rod 12
Since the bearings 13 and 1 are only in contact with each other and are not connected and fixed, the force acting perpendicularly to the axial direction of the movable iron core 17 due to biased magnetic force is not transmitted to the push-down rod 12.
This has the effect of preventing a load due to biased magnetic force from being applied to 6.

Therefore, the wear of the bearings 13 and 16 is reduced and the life of the bearings 13 and 16 is improved.

This has the effect of smoothing the operation of the push-down rod 12 due to the suction operation of the movable core 17 and improving the reliability of the device.

As described above, according to the electromagnetic braking device of the present invention, the operation of the push-down rod accompanying the suction operation of the movable iron core can be made stable and smooth, and the wear of the bearing portion that supports the push-down rod can be reduced. It is effective.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing the structure of a conventional electromagnetic braking device, FIG. 2 is a longitudinal sectional view showing an example of the electromagnet shown in FIG. 1, and FIG. 3 is an example of an electromagnetic braking device of the present invention. FIG. 2 is a longitudinal cross-sectional view showing the structure of an electromagnet that is a main part of the embodiment. 1... Brake tram, 5... L/Gover 9... Yoke, 10... Excitation coil, 11... Fixed iron core, 12...-Pushing down rod, 14,16...Bearing, 1T...
...Movable iron core, 30...Electromagnet.

Claims (1)

[Claims] 1. A yoke forming an outer shell, a cylindrical excitation coil built into the yoke, and a cylindrical excitation coil disposed inside this excitation coil,
a fixed iron core fixed to the yoke; a movable iron core disposed opposite to the fixed iron core and attracted to the fixed iron core;
An electromagnet is provided which has a push-down rod that is moved in the axial direction by the movable core and is supported by a bearing in a through hole opened in the fixed core, and by moving the push-down rod in the axial direction, a pair of In an electromagnetic braking device that releases the braking force of a braking spring applied to a drum through a rotor, two bearings are provided in a through hole of a fixed core, and a push-down rod is provided that is supported by these two bearings. An electromagnetic braking device characterized in that a yoke inner end of a push-down rod is brought into contact with a movable iron core.