WO2020021632A1

WO2020021632A1 - Electromagnetic brake device and hoist

Info

Publication number: WO2020021632A1
Application number: PCT/JP2018/027699
Authority: WO
Inventors: 前田　徹
Original assignee: 三菱電機株式会社
Priority date: 2018-07-24
Filing date: 2018-07-24
Publication date: 2020-01-30
Also published as: JP6704533B1; JPWO2020021632A1

Abstract

The present invention provides an electromagnetic brake device and a hoist, which can shorten time from the issuance of a braking command to the start of braking. The electromagnetic brake device according to the present invention is provided with: a needle; a yoke; a brake spring that is installed between the needle and the yoke and that pushes the needle in a direction away from the yoke; a plurality of coils that are arranged in the yoke and that magnetically attract the needle in opposition to the spring force of the brake spring; and a control unit that supplies current of the same direction to the coils when braking is cancelled, and supplies, when braking is started, current of a direction opposed to that of the current supplied when the braking is cancelled, to a portion of the coils while stopping the current supply to the remaining coils.

Description

Electromagnetic brake device and hoist

The present invention relates to an electromagnetic brake device and a hoist provided with the electromagnetic brake device.

A conventional electromagnetic brake device includes a brake disk that rotates integrally with a rotor, a fixed plate provided on one side in the axial direction of the brake disk, and a fixed plate that sandwiches the brake disk in the axial direction, and A magnetic plate provided movably in the axial direction, a spring member for pressing the magnetic plate against the brake disk, a coil for electromagnetically attracting the magnetic plate against the pressing force of the spring member, and a yoke for fixing the coil, The coil is an inner / outer double coil in which two annular coils having different diameters are arranged concentrically apart from each other (for example, see Patent Document 1).

Published Japanese Utility Model Application No. Hei 6-74066

(4) In the conventional electromagnetic brake device, when the energization of the double coil is stopped in response to the braking command, a residual magnetic flux that acts to electromagnetically attract the magnetic plate is generated. As a result, there is a problem that the time from the braking command to the start of braking becomes longer.

The present invention has been made to solve such a problem, and an object of the present invention is to provide an electromagnetic brake device and a hoist that can shorten the time from a braking command to the start of braking.

An electromagnetic brake device according to the present invention includes a mover, a yoke, a braking spring that is installed between the mover and the yoke, and that pushes the mover in a direction away from the yoke, and that is disposed on the yoke. A plurality of coils for magnetically attracting the mover against the spring force of the braking spring, and a current in the same direction is applied to each of the plurality of coils at the time of braking release, and the plurality of coils of A control unit configured to supply current to a part of the coils in a direction opposite to the current supplied when the brake is released, and to stop supplying power to the remaining coils.

According to the present invention, since the residual magnetic flux acting to magnetically attract the mover disappears, it is possible to realize an electromagnetic brake device and a hoist that can reduce the time from a braking command to the start of braking.

FIG. 1 is a schematic diagram illustrating an overall configuration of an elevator apparatus according to Embodiment 1 of the present invention. FIG. 2 is a cross-sectional view illustrating a main part of the hoist according to the first embodiment of the present invention. FIG. 2 is a circuit diagram of the electromagnetic brake device according to Embodiment 1 of the present invention. FIG. 2 is a cross-sectional view showing a brake release state in the electromagnetic brake device according to Embodiment 1 of the present invention. FIG. 2 is a cross-sectional view showing a state immediately after stopping energization of the coil in the electromagnetic brake device according to Embodiment 1 of the present invention. FIG. 2 is a sectional view showing a state at the time of starting braking in the electromagnetic brake device according to Embodiment 1 of the present invention. FIG. 7 is a cross-sectional view illustrating an electromagnetic brake device according to Embodiment 2 of the present invention. FIG. 13 is a cross-sectional view illustrating an electromagnetic brake device according to Embodiment 3 of the present invention.

Embodiment 1 FIG.
FIG. 1 is a schematic diagram illustrating an overall configuration of an elevator apparatus according to Embodiment 1 of the present invention. FIG. 2 is a cross-sectional view illustrating a main part of a hoist according to Embodiment 1 of the present invention. FIG. 2 is a circuit diagram of the electromagnetic brake device according to Embodiment 1 of the present invention.

In FIGS. 1 and 2, the elevator apparatus 100 includes a hoist 3 installed in a machine room 2 above the hoistway 1, and a hoist 4 wound around the hoist 3 in the hoistway 1. It comprises a hanging wire rope 5, a car 6 and a counterweight 7 connected to both ends of the wire rope 5. Then, the hoist 3 is driven, and the car 6 is guided by the car guide rails 8 and moves up and down in the hoistway 1. The counterweight 7 moves up and down while being guided by a weight guide rail (not shown) in conjunction with the elevation of the car 6. An elevator control device 9 for controlling the driving of the hoist 3 is installed in the machine room 2.

The hoist 3 includes a sheave 4, an output shaft 3 a that transmits the driving force of the motor unit to the sheave 4, a brake disc 12 that rotates in conjunction with the rotation of the output shaft 3 a, and a braking force applied to the brake disc 12. And an electromagnetic brake device 20 that acts on The output shaft 3 a is rotatably supported at both ends by a support base 11 attached to the upper surface of the steel material 10. The sheave 4 is fixed to the output shaft 3a. The brake disk 12 is fixed to the side surface of the sheave 4 with bolts or the like, and is rotatable integrally with the sheave 4. The surface of the brake disk 12 opposite to the sheave 4 serves as a braking surface 12a. The electromagnetic brake device 20 is supported by the support base 11 and installed on the opposite side of the sheave 4 of the brake disk 12 with the output shaft 3a interposed therebetween.

The electromagnetic brake device 20 is made of a mover 21 made of a magnetic material, a brake pad 22 fixed to one surface of the mover 21, and a magnetic material installed on the other surface of the mover 21. A yoke 23, a coil 24 mounted on the yoke 23 and exciting to generate a magnetic attraction force, and a braking spring 25 for generating a braking force. The mover 21 is mounted on the yoke 23 and is capable of reciprocating in a direction approaching the yoke 23 and in a direction away from the yoke 23. A braking spring 25 is provided between the mover 21 and the yoke 23, and presses the mover 21 in a direction away from the yoke 23. Note that the mover 21, the yoke 23, the coil 24, and the braking spring 25 form an electromagnet.

The electromagnetic brake device 20 configured as described above is fixed to the support base 11 with bolts or the like, and is installed with the brake pad 22 facing the brake disk 12. Thereby, the brake pad 22 comes into contact with the braking surface 12a or separates from the braking surface 12a in conjunction with the reciprocating movement of the mover 21. When the current supply to the coil 24 is stopped, the mover 21 moves in the direction of the brake disk 12 by the spring force of the braking spring 25. Thereby, the brake pad 22 is pressed against the braking surface 12a, and the output shaft 3a is braked. As a result, the drive of the hoisting machine 3 is braked. To release the braking by the electromagnetic brake device 20, the coil 24 is energized to generate a magnetic field. This magnetic field acts on the yoke 23, and the yoke 23 becomes magnetic. As a result, the mover 21 is drawn toward the yoke 23 against the spring force of the braking spring 25 and comes into contact with the yoke 23. Thereby, the brake pad 22 separates from the braking surface 12a of the brake disc 12, and the braking is released.

Here, the specific structure of the electromagnetic brake device 20 will be described with reference to FIG.

The yoke 23 is made of, for example, a magnetic material and has a rectangular parallelepiped shape, and has an annular groove 26 formed in the center of the surface on the movable element 21 side. Therefore, the yoke 23 moves the cylindrical inner pole portion 23a inside the groove 26, the annular outer pole portion 23b outside the groove 26, and the inner pole portion 23a and the outer pole portion 23b opposite to the mover 21. And a bottom portion 23c connected on the side. The coil 24 includes a first coil 24a and a second coil 24b formed in the same cylindrical shape. The first coil 24a and the second coil 24b are coaxially housed in the groove 26 in two layers in the reciprocating direction of the mover 21. The braking spring 25 is housed in, for example, grooves 27 provided at four corners of the surface of the yoke 23 on the movable element 21 side, and presses the movable element 21 in a direction away from the yoke 23.

As shown in FIG. 3, the electromagnetic brake device 20 includes a first AC power supply 31a for supplying current to the first coil 24a, a second AC power supply 31b for supplying current to the second coil 24b, Is provided. The electromagnetic brake device 20 further includes a first switch 32a provided in a power supply path between the first coil 24a and the first AC power supply 31a, and a power supply path between the second coil 24b and the second AC power supply 31b. And a control unit 30 that controls the operation of the first switch 32a and the second switch 32b. The first switch 32a switches the phase of the current supplied to the first coil 24a from the first AC power supply 31a and cuts off the current. The second switch 32b switches the phase of the current supplied from the second AC power supply 31b to the second coil 24b and cuts off the current. The control unit 30 controls a switching operation between the first switch 32a and the second switch 32b based on a braking command or a braking release command from the elevator control device 9.

Next, the operation of the electromagnetic brake device 20 will be described with reference to FIGS. FIG. 4 is a cross-sectional view showing a brake release state in the electromagnetic brake device according to the first embodiment of the present invention, and FIG. 5 is a state immediately after stopping energization of the coil in the electromagnetic brake device according to the first embodiment of the present invention. FIG. 6 is a cross-sectional view showing a state of the electromagnetic brake device according to Embodiment 1 of the present invention at the start of braking. 4 to 6, hatching is omitted so that the flow of the magnetic flux is easy to see.

First, in a state where the first coil 24a and the second coil 24b are not energized, the pressing force of the braking spring 25 acts on the mover 21. Thereby, as shown in FIG. 2, the brake pad 22 is pressed against the braking surface 12a of the brake disk 12. As a result, the rotation of the output shaft 3a of the hoist 3 is braked, and the landing state of the car 6 is maintained.

Next, when a car call occurs, a braking release command is sent from the elevator control device 9 to the control unit 30. Therefore, the control unit 30 controls the switching operation between the first switch 32a and the second switch 32b. As a result, an alternating current having the same phase is supplied to the first coil 24a and the second coil 24b from the first AC power supply 31a and the second AC power supply 31b.

電流 Thus, currents in the same direction flow in the first coil 24a and the second coil 24b, and magnetic fluxes 35a and 35b flowing to the right side in the inner pole portion 23a in FIG. 4 are generated. As a result, the magnetic fluxes 35a and 35b flow from the inner pole portion 23a to the mover 21, and flow from the mover 21 to the magnetic path returning to the inner pole portion 23a via the outer pole portion 23b and the bottom portion 23c. As a result, as shown in FIG. 4, the mover 21 is magnetically attracted to the yoke 23 against the pressing force of the braking spring 25, and the brake pad 22 separates from the braking surface 12 a of the brake disk 12. As a result, the braking of the output shaft 3a is released. Then, the output shaft 3a of the hoisting machine 3 is driven to rotate, the sheave 4 is driven to rotate in synchronization with the output shaft 3a, and the car 6 moves up and down.

Next, when the car 6 arrives on the floor, a braking command is sent from the elevator control device 9 to the control unit 30. Here, a case will be described in which the control unit 30 operates the first switch 32a and the second switch 32b so as to stop energizing the first coil 24a and the second coil 24b. In this case, the state is changed from the state in which the same phase current is applied to the first coil 24a and the second coil 24b to the state in which the current supply to the first coil 24a and the second coil 24b is stopped. At this time, the magnetic flux does not completely disappear, and a part of the magnetic flux remains. As shown in FIG. 5, the residual magnetic flux 36 flows from the inner pole part 23a to the mover 21, and then flows from the mover 21 to the magnetic path returning to the inner pole part 23a via the outer pole part 23b and the bottom part 23c. When the residual magnetic flux 36 flows through this magnetic path, a force for electromagnetically attracting the mover 21 is generated, and acts to delay the braking operation.

In the first embodiment, when receiving the braking command, the control unit 30 operates the first switch 32a so as to stop energizing the first coil 24a. Further, the control unit 30 operates the second switch 32b such that a current having a phase opposite to that of the current that was supplied at the time of the braking release command is supplied to the second coil 24b. As a result, a current flows in the second coil 24b in a direction opposite to the current flowing at the time of the braking release command, and as shown in FIG. 6, a magnetic flux 37b flowing to the left through the inner pole portion 23a is generated. As a result, the magnetic flux 37b flows from the inner pole portion 23a to the bottom portion 23c, and flows from the bottom portion 23c through the outer pole portion 23b and the mover 21 to the magnetic path returning to the inner pole portion 23a. Since the magnetic flux 37b flows in the opposite direction to the residual magnetic flux 36, the residual magnetic flux 36 is canceled by the magnetic flux 37b. Thereby, the residual magnetic flux 36 acting to delay the braking operation disappears, and the time from the braking command to the start of braking is reduced.

At the time of braking release, a current having the same phase is applied to the first coil 24a and the second coil 24b which are disposed in the groove 26 forming the inner pole portion 23a so as to overlap in the groove depth direction. Therefore, the magnetic flux generated by the first coil 24a and the second coil 24b is not canceled. As a result, a sufficient braking release force can be secured, and it is not necessary to increase the size of the first coil 24a and the second coil 24b.

The first coil 24a and the second coil 24b are connected to the dedicated first AC power supply 31a and second AC power supply 31b via the first switch 32a and the second switch 32b, respectively. Then, the control unit 30 switches between the first switch 32a and the second switch 32b at the start of braking to stop energizing the first coil 24a, and determines the current that has been applied to the second coil 24b when braking is released. Are conducting currents of opposite phases. Therefore, the controller 30 does not need to perform complicated control such as adjusting the current of the second AC power supply 31b so that the residual magnetic flux can be eliminated.

Note that the electromagnetic attraction force due to the magnetic flux 37b is half of the electromagnetic attraction force due to the magnetic fluxes 35a and 35b when the brake is released, and is smaller than the spring force of the braking spring 25. Has no effect. Therefore, the application of the current of the opposite phase to the second coil 24b may be continued during braking, but it is preferable to stop the conduction when the residual magnetic flux 36 disappears. That is, it is preferable that the application of the current having the opposite phase to the second coil 24b be limited at the time of starting the braking.

In the first embodiment, only the second coil 24b is energized, but only the first coil 24a may be energized.
Further, in the first embodiment, the power supply for supplying power to the first coil 24a and the second coil 24b is an AC power supply, but the power supply for supplying power to the first coil 24a and the second coil 24b may be a DC power supply. In this case, at the time of braking release, a current having the same direction may be applied to the first coil 24a and the second coil 24b. Then, at the start of braking, the current supply to the first coil 24a may be stopped, and a current opposite to the current supplied at the time of braking release may be supplied to the second coil 24b.

Embodiment 2 FIG.
FIG. 7 is a sectional view showing an electromagnetic brake device according to Embodiment 2 of the present invention.

In FIG. 7, the mover 21A and the yoke 23A are configured by laminating magnetic thin plates 40a made of an electromagnetic steel sheet in the moving direction of the mover 21A.

Embodiment 2 is different from Embodiment 2 in that the mover 21A and the yoke 23A made of a laminated body of the magnetic thin plates 40a are used instead of the mover 21 and the yoke 23 made of a lump of magnetic material. Thus, the configuration is the same as that of the first embodiment. Therefore, in the second embodiment, the same effect as in the first embodiment can be obtained.

In the second embodiment, the mover 21A and the yoke 23A are configured by a laminated body of the magnetic thin plates 40a. Thus, the generation of eddy currents in the mover 21A and the yoke 23A is suppressed, so that the magnetic flux generated by the eddy currents is reduced, and the time from a braking command to the start of braking is further reduced.

Embodiment 3 FIG.
FIG. 8 is a sectional view showing an electromagnetic brake device according to Embodiment 3 of the present invention.

In FIG. 8, the mover 21B and the yoke 23B are configured by laminating a magnetic thin plate 40b made of an electromagnetic steel sheet in a direction orthogonal to the moving direction of the mover 21B.
The other configuration is the same as that of the second embodiment.

The third embodiment has the same configuration as that of the second embodiment except that the laminating direction of the magnetic thin plate 40b of the mover 21B and the yoke 23B is different from the laminating direction of the magnetic thin plate 40a of the mover 21A and the yoke 23A. Have been. Therefore, in the third embodiment, the same effect as in the second embodiment can be obtained.

Here, in

Embodiments

2 and 3, the mover and the yoke are formed of a laminated body in which magnetic thin plates are stacked in the same direction. However, the stacking direction of the magnetic thin plates of the mover and the magnetic thin plate of the yoke are different. It may be composed of a laminate having a different lamination direction. Further, one of the mover and the yoke may be formed of a lump, and the other may be formed of a laminate.

In each of the above embodiments, the two coils are arranged on the surface of the mover side of the yoke so as to overlap in the moving direction of the mover. The number may be three or more. In this case, when braking is released, a current in the same direction is supplied to each of the coils from a dedicated power supply, and when braking is started, for example, a current in the opposite direction is supplied to one coil, and power supply to the other coils is stopped. Good.

In each of the above embodiments, the first coil and the second coil are formed in the same annular shape, and are coaxially arranged on the surface of the yoke on the mover side so as to overlap in the moving direction of the mover. However, the first coil and the second coil may be formed in an annular shape having different diameters, and may be arranged concentrically close to each other on the movable element side surface of the yoke.

Also, in each of the above embodiments, the electromagnetic brake device is described as being applied to a disk brake type hoist, but the electromagnetic brake device may be applied to a drum brake type hoist. .
Further, in each of the above embodiments, the electromagnetic brake device is described as being applied to the hoist of the elevator device. However, the electromagnetic brake device may be applied to braking of a motor for other uses.

3 hoist, 20 electromagnetic brake device, 21, 21A, 21B mover, 23, 23A, 23B yoke, 24 coil, 24a first coil, 24b second coil, 25 braking spring, 30 control unit, 40a, 40b magnetic Thin plate.

Claims

Mover,
York and
A braking spring that is installed between the mover and the yoke and pushes the mover away from the yoke;
A plurality of coils arranged on the yoke for magnetically attracting the mover against the spring force of the braking spring;
At the time of braking release, a current in the same direction is supplied to each of the plurality of coils, and at the time of braking start, a current in the opposite direction to the current supplied at the time of braking release is supplied to some of the plurality of coils. An electromagnetic brake device comprising: a control unit that energizes and stops energizing the remaining coils.
The electromagnetic brake device according to claim 1, further comprising a dedicated power supply for each of the plurality of coils.
(3) The electromagnetic brake device according to (1) or (2), wherein the yoke is constituted by a laminated body of magnetic thin plates.
The electromagnetic brake device according to any one of claims 1 to 3, wherein the mover is formed of a laminate of magnetic thin plates.
A hoist comprising the electromagnetic brake device according to any one of claims 1 to 4.