JPH0814283A - Multipolar electromagnetic brake - Google Patents

Abstract

PURPOSE:To provide a multipolar electromagnetic brake in which the number of part items can be reduced without loosing the structural reliability. CONSTITUTION:A multipolar electromagnetic brake 10 has a base part 12, a plurality of core parts 14 fixed to the base part 12, an exciting coil 15 wound on each core part 14, an end plate 20 fixed to the base part 12 with an axial space from the top end surface 18 of each core part 14, and a friction plate 22 arranged between the top end surface 18 of each core part 14 and the end plate 20 in such a manner as to be axially movable and connected to a rotor 28. This brake further has an armature 24 arranged between the top end surface 18 of each core part 14 and the friction plate 22 in such a manner as to be only axially movable and a plurality of compression coil springs 26 for energizing the armature 24 in the direction getting close to the end plate 20. The core parts 14 are formed by cutting and bending required parts of the base part 12 by a press machine.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic brake, and more particularly to a friction plate type multi-pole for braking or releasing the rotational movement of a friction plate connected to a braked rotating body by turning on / off electromagnetic force generated in a plurality of magnetic poles. Regarding electromagnetic brakes.

[0002]

2. Description of the Related Art A friction plate type electromagnetic brake, for example, an output shaft of an electric motor that supports the weight of a driven body when it is stopped in a driving portion of a machine tool, rotates a rotating body that is to be rotated by a static load applied from the outside. It is preferably used for braking and holding. In this type of friction plate type electromagnetic brake, a plurality of columnar core portions around which excitation windings are wound are fixed to a ring-shaped base portion that is placed stationary and surrounds the braked rotating body in a non-contact manner. Multi-pole electromagnetic brakes are known.

In this multi-pole electromagnetic brake, a plurality of core portions each carry an excitation winding, extend in the axial direction around the braked rotating body, and are located at positions axially separated from the tip surfaces of the core portions. , An annular end plate fixedly connected to the base. Further, an annular friction plate is arranged between the tip surface of the core portion and the end plate, and is connected to the braked rotating body so as to be able to move in the axial direction in a minute manner. Is an annular armature that is attracted to the core portion by an electromagnetic force, that is, a movable iron plate is arranged so as to be movable only in the axial direction. A plurality of compression coil springs are arranged in a compressed state between the armature and the base as elastic members for urging the armature in a direction approaching the end plate. When the excitation winding is de-energized, the friction force is held between the armature and the end plate by the spring force of the compression coil spring, and the rotor is braked and held by the friction between the armature and the end plate. When the excitation winding is energized, the armature is attracted by the electromagnetic force to the core portion against the spring force of the compression coil spring,
The rotating body is released from the braking state.

[0004]

In the conventional multi-pole electromagnetic brake, the base is generally formed by pressing from a sheet metal material, and a plurality of pillar-shaped cores formed in separate steps are attached to the base by bolts or adhesives. It was fixedly connected. In that case, since the number of cores corresponding to the number of poles is prepared, the number of parts is increased, which consumes a great deal of time and labor for assembling work, and there is a problem that inventory management becomes complicated. An object of the present invention is to provide a multi-pole electromagnetic brake capable of reducing the number of parts without impairing the structural reliability and thus reducing the time and labor consumed in the assembly work.

[0005]

In order to achieve the above object, the present invention provides a base portion which is stationary around the braked rotating body, and an excitation winding which is axially projected from the base portion. A plurality of core portions, an end plate that is axially separated from the tip end surfaces of the plurality of core portions in the protruding direction and fixed to the base portion, and is disposed between the tip end surface of the core portion and the end plate. A friction plate that is movably connected to the rotating body in the axial direction, and is arranged so as to be movable only in the axial direction between the tip surface of the core portion and the friction plate,
A multipolar electromagnetic brake including an armature that is attracted to the core portion by electromagnetic force, and an elastic member that urges the armature toward the end plate to hold the friction plate by braking between the armature and the end plate. In, the plurality of core portions are formed by plastically deforming a desired portion of the base portion, and thus the base portion and the core portion are integrally connected to each other to provide a multipolar electromagnetic brake.

[0006]

[Function] When a plurality of core portions are formed by plastically deforming a desired portion of the base portion, the core portions are integrally connected to the base portion, so that even when the armature is attracted by electromagnetic force, stable excitation is achieved. Demonstrates sufficient mechanical strength to hold the winding in place. By integrally molding the base portion and the core portion in this way, it is not necessary to prepare a separate core portion, and the number of parts of the multipolar electromagnetic brake is reduced.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described in more detail with reference to the preferred embodiments shown in the accompanying drawings. 1 to 3 show a multi-pole electromagnetic brake 10 according to an embodiment of the present invention. The electromagnetic brake 10 includes a ring-plate-shaped base portion 12 that is stationary, a plurality of columnar core portions 14 that are fixedly connected to the base portion 12 and project in the axial direction, and each core portion 14
The excitation winding 16 wound around the end plate 20, the end plate 20 fixedly coupled to the base portion 12 at a position axially separated from the projecting end surface 18 of each core portion 14, and the end surface of each core portion 14. 18
And the end plate 20, the annular friction plate 22 rotatably and movably in the axial direction, and the tip end surface 1 of each core portion 14.
8 and the friction plate 22 are provided with an annular plate-shaped armature 24 arranged so as to be movable only in the axial direction, and a plurality of compression coil springs 26 for urging the armature 24 toward the end plate 20. .

The base 12, the end plate 20, the friction plate 22, and the armature 24 are concentrically arranged side by side in the axial direction,
A braked rotating body 28 such as a shaft of an electric motor is inserted through each central opening. The base 12 surrounds the rotating body 28 in a contactless manner and is fixed to a given stationary body (not shown) by, for example, a bolt 30 (FIG. 2). Similarly, the end plate 20 surrounds the rotating body 28 in a non-contact manner. A plurality of spacing pipes 32 are arranged between the base 12 and the end plate 20, and a bolt 34 penetrating the end plate 20 and each spacing pipe 32 is screwed into a screw hole 36 formed in the base 12. , The end plate 20 is the base 12
Fixedly connected to. The friction plate 22 is coupled to the rotating body 28 by a spline ring 40 closely fitted to the rotating body 28 so that the spline portion 38 provided in the center opening of the friction plate 22 is finely movable in the axial direction. Rotate with 28.

The armature 24 is made of a magnetic material and surrounds the rotating body 28 in a non-contact manner so as to surround the tip surface 18 of each core portion 14.
Is placed opposite to. In the armature 24, the spacing pipe 32 is loosely fitted in each of the plurality of holes 42 provided in the outer edge portion, and only between the tip end surface 18 of each core portion 14 and the friction plate 22 along the spacing pipe 32 in the axial direction. It is movable. A compression coil spring 26 surrounds each spacing tube 32 and is disposed in a compressed state between the base 12 and the armature 24. When the excitation winding 16 is not energized, the armature 24 is pressed against the friction plate 22 by the spring force of the compression coil spring 26. As a result, the friction plate 22 and the end plate 20 and the armature 2 are
4, which is closely clamped between the end plate 20 and the armature 2.
The rotor 28 is held by braking due to the friction between the friction plate 4 and the friction plate 22. When the excitation winding 16 is energized, the armature 24 is attracted to the core portion 14 by the electromagnetic force, and the compression coil spring 2
6 slides axially along the spacing tube 32 against the spring force of 6. As a result, the friction between the end plate 20, the armature 24 and the friction plate 22 is eliminated, and the rotating body 28 is released from the braking state.

As shown in the drawing, each exciting winding 16 is preferably wound in advance on a bobbin 44 made of, for example, a resin material having an electric insulation property. In that case, by inserting the core portion 14 into the center hole 46 of the bobbin 44, the bobbins 44 carrying the excitation windings 16 are attached to the respective core portions 14. The core portion 14 and the bobbin 44 can be fixed to each other by, for example, an adhesive. With such a structure, the winding work of the excitation winding 16 on the core portion 14 is facilitated, and the electrical insulation and fixing of the excitation winding 16 to the core portion 14 can be obtained in one step.

Multipolar electromagnetic brake 1 according to an embodiment of the present invention
0 has a very advantageous structure in which the base portion 12 and the plurality of core portions 14 are integrally molded. That is, the plurality of core portions 14
Are formed by cutting and bending a desired portion of the base 12 with a press machine. As shown in FIG. 4, in the electromagnetic brake 10, the core portions 14 are circumferentially arranged at substantially equal intervals between the inner edge portion and the outer edge portion of the base portion 12 in the circumferential direction. In order to realize such an arrangement, a pair of substantially parallel notches 48 extending inward in the radial direction from the outer edge portion are formed at four locations at equal intervals in the circumferential direction of the base portion 12, and the pair of notches 48 are provided at each location. Each core portion 14 is formed by bending the sandwiched portion until it is substantially orthogonal to the base portion 12. The cutting and bending steps may be performed sequentially as described above, but may be performed simultaneously depending on the thickness of the base portion 12. After cutting and bending by a press machine, each core portion 14 is preferably subjected to a surface treatment by a polishing step, whereby burrs and sags are corrected and a substantially square pillar-shaped core portion 14 is formed as shown in the figure. . Furthermore, through holes 50 for the bolts 30 and 34 (FIG. 2) are formed in the base portion 12 having the plurality of core portions 14 by drilling.

In the electromagnetic brake 10, the base 12 has a thickness of, for example, 5 mm to 15 mm, preferably 8 mm to 12 mm. If the thickness of the base portion 12 is larger than this range, it becomes difficult to form the core portion 14 by a press machine, and if it is smaller than this range, the rigidity of the base portion 12 when attaching the electromagnetic brake 10 to a given machine body and the magnetic path formed by the base portion 12 are difficult. The cross-sectional area of is insufficient. The base 12 is made of a magnetic metal material such as iron or copper. Generally, the base portion of the multi-pole electromagnetic brake is processed and formed from such a sheet metal material of magnetic metal by a pressing machine and a polishing machine. Therefore, the base portion 12 and the core portion 14 of the electromagnetic brake 10 should be formed by pressing and polishing. Is advantageous in that the press machine and polishing machine used in the conventional molding process can be used.

In the electromagnetic brake 10, the circumferential dimension of the core portion 14, that is, the distance between the pair of substantially parallel notches 48 is, for example, 5 mm to 30 mm, preferably 8 mm to 15 mm.
Is. Further, the bobbin 44 carrying the excitation winding 16 and attached to the core portion 14 has a square columnar center hole 46 corresponding to the core portion 14. The bobbin 44 energizes the excitation winding 16 to attract the armature 24, and
Must be firmly fixed and supported by. For that purpose, for example, the bobbin 44 can be fixed to the core portion 14 with an adhesive having excellent adhesive strength, heat resistance, and electrical insulation. An adhesive that is preferably used for fixing the core portion 14 and the bobbin 44 to each other is an epoxy adhesive.

As shown in FIG. 5A, a pair of substantially parallel notches 52 extending radially outward from the inner edge of the base portion 12.
It is also possible to form a core portion 54 defined by Further, a portion 56 that slightly protrudes laterally is formed at the tip of the core portion 14 (FIG. 5B), whereby the excitation winding 1
Mutual fixing of the bobbin 44 carrying 6 and the core portion 14 with an adhesive can be assisted. Furthermore, FIG.
As shown in, the core portion 62 having the projecting edge portion 60 that extends laterally at the tip can be formed by the step 58 that extends stepwise at the outer edge portion of the base portion 12. In this case, the excitation winding 16 can be directly wound around the core portion 62 by covering the surfaces of the base portion 12 and the core portion 62 with the insulating coating 64 (FIG. 6B).

The core portion of the multi-pole electromagnetic brake according to the present invention can be formed by plastically deforming the base portion by various methods other than the cutting and bending. For example, as shown in FIG. 7, an annular core portion 68 can be formed by burring a desired portion of the base portion 66. In this case, for example, the base 66 may be formed of a laminated body of a plurality of magnetic thin plates, and the burring process may be performed only on the uppermost thin plate 70. The core portion 68 is preferably surface-treated by a polishing process. The bobbin 74 having the corresponding cylindrical center hole 72 and carrying the excitation winding 16 is attached to the thus formed annular core portion 68. In addition, in order to improve the magnetic circuit characteristics and mechanical strength of the core portion 68, a columnar separate core member 76 may be arranged inside the core portion 68.
Mutual fixing of the core portion 68 to the bobbin 74 and the core member 76 can be obtained by an epoxy adhesive. Further, a deep drawing process may be performed instead of the burring process so that the core 68 has a closed end.

[0016]

As is apparent from the above description, according to the present invention, a plurality of core portions are formed by plastically deforming a desired portion of the base portion, and thus the base portion and the core portion are integrally connected. Since the configuration is adopted, it is possible to reduce the number of parts of the multipolar electromagnetic brake without impairing the structural reliability. Therefore, according to the present invention, the assembly and the parts management of the multi-pole electromagnetic brake become extremely easy.

[Brief description of drawings]

FIG. 1 is a diagram of a multi-pole electromagnetic brake according to an embodiment of the present invention and is a cross-sectional view taken along line I-I of FIGS. 2 and 3.

FIG. 2 is a plan view of the multipolar electromagnetic brake of FIG.

3 is a cross-sectional plan view of the multi-pole electromagnetic brake of FIG. 1 taken along line III-III.

FIG. 4 is a perspective view showing a base structure of the multipolar electromagnetic brake of FIG.

5A and 5B are diagrams of a modified example of the base structure of FIG. 4, and FIG. 5A is a partially enlarged perspective view and FIG. 5B is a partially enlarged sectional view taken along line VV.

6A and 6B are views of another modified example of the base structure of FIG. 4, and FIG. 6A is a partially enlarged perspective view and FIG. 6B is a partially enlarged cross-sectional view taken along line VI-VI.

FIG. 7 is a diagram showing a base structure of a multipolar electromagnetic brake according to another embodiment of the present invention, in which (a) is a perspective view and (b) is a line VII.
FIG. 7 is a partially enlarged sectional view taken along line VII.

[Explanation of symbols]

 12, 66 ... Base portion 14, 54, 62, 68 ... Core portion 16 ... Excitation winding 18 ... Tip surface 20 ... End plate 22 ... Friction plate 24 ... Armature 26 ... Compression coil spring 28 ... Rotating body 30, 34 ... Bolt 44 , 74 ... Bobbin 48, 52, 58 ... Notch

Claims (1)

[Claims] 1. A base part which is arranged stationary around the braked rotating body, a plurality of core parts which project in the axial direction from the base part and are respectively wound with excitation windings, and a plurality of protrusions of the core parts. The end plate that is axially separated from the front end surface and fixed to the base portion, and is disposed between the front end surface and the end plate of the core portion, and is movably connected to the braked rotating body in the axial direction. Friction plate,
An armature, which is arranged so as to be movable only in the axial direction between the tip end surface of the core portion and the friction plate, is attracted to the core portion by an electromagnetic force, and an armature attached in a direction of approaching the end plate. In a multi-pole electromagnetic brake comprising an elastic member for biasing and holding the friction plate between the armature and the end plate, the plurality of core parts plastically deform a desired part of the base part. A multi-pole electromagnetic brake, characterized in that the base portion and the core portion are integrally connected.