JPH0511385Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a negatively actuated electromagnetic brake that releases the braking of shaft rotation when the electromagnetic coil is energized, and brakes the shaft rotation when the electromagnetic coil is de-energized.

[Conventional technology]

Electromagnetic brakes are broadly classified into positive-acting type and negative-acting type, depending on whether the shaft rotation is braked or released when the electromagnetic coil is energized. 1977-
The one disclosed in Publication No. 187106 is known. The negative actuation type electromagnetic brake described here is equipped with an annular field that is fixed to the equipment fixing part and has an electromagnetic coil inside, and a side plate is attached to the attraction surface side of this field. They are fixed concentrically across a predetermined space. In the space between the field and the side plate, an annular armature is provided so as to be slidable but non-rotatable with its plane facing the suction surface of the field. An integrated disk is interposed between the device fixing portion and the disk so as to be slidable in the rotational direction via a shaft and a hub rotatably supported by the device fixing portion. Friction plates are affixed to both sides of this disk, each facing the plane of the armature and side plate, and the field side has an elastic force in the direction of separating the armature from the suction surface. A brake spring is provided.

With this configuration, when the electromagnetic coil is excited and the armature resists the elastic force of the braking spring and is attracted to the attraction surface of the field, the friction plates on both sides of the disk are released from pressure, so that the disk The integral shaft in the direction of rotation becomes unbraked, and when driven, it rotates.

From this state, when the drive of the shaft is released and the electromagnetic coil is demagnetized, the armature is separated from the attraction surface of the field by the elastic force of the braking spring, and the disk is moved and the friction plates on both sides are connected to the armature and side plate. Since the disc is brought into pressure contact with the disc, the rotation of the disc is braked, and the shaft integrated with the disc is braked in the direction of rotation.

The field in this negative actuation type electromagnetic brake is formed by an annular yoke forged from steel and a mounting back plate that closes the open end of the annular groove.The yoke is equipped with an electromagnetic coil. The above-mentioned annular groove for storing the magnet and a narrow annular groove that communicates with the annular groove and opens to the attraction surface are provided, and a magnetic flux path that bypasses the armature is formed using the narrow annular groove as a demagnetizing part. There is.

[The problem that the idea aims to solve]

However, as mentioned above, the field in such conventional negative actuating electromagnetic brakes is a forged yoke, which does not reduce the overall weight of the electromagnetic brake. The manufacturing process requires many steps, such as bonderite processing of the surface, cold forging to create an annular member with an annular groove, forming a narrow annular groove, and then finishing the suction surface with cutting. There was a problem with rising costs.

[Means to solve the problem]

In order to solve such problems, this invention
A yoke made of a steel plate material having an annular shape as a whole and having an annular groove for storing an electromagnetic coil and a slit concentrically formed in the bottom plate of the annular groove, and the yoke can move forward and backward with respect to the end face of the bottom plate. An armature supported by the base plate was provided as a component of a negative operation type electromagnetic brake, and a guide member for regulating rotation of the armature was screwed and fixed to a protrusion formed on the bottom plate. Further, in the second aspect of the present invention, the guide member is fixed to an outer side plate formed by cutting and raising a yoke.

[Effect]

When the electromagnetic coil is energized and the armature resists the elastic force of the brake spring and is attracted to the attraction surface of the field, the friction plates on both sides of the disk are released from pressure, so that the shaft integrated with the disk applies braking in the rotational direction. It is in an unraveled state, and when you drive it, it rotates. From this state, when the drive of the shaft is released and the electromagnetic coil is demagnetized, the armature is separated from the attraction surface of the field by the elastic force of the braking spring, and the disk moves and the friction plates on both sides are pressed together. The rotation of the disk is braked, and the shaft integral with the disk is braked in the direction of rotation. Since the yoke of this negative-actuation type electromagnetic brake is made of a plate material, it is lightweight and requires fewer steps, and the armature guide member is screwed into the protrusion on the yoke bottom plate, so the armature is firmly supported. Ru. Furthermore, since the guide member is fixed to the outer side plate formed by cutting and raising the yoke, the diameter of the disk is not restricted by the guide member.

〔Example〕

1 to 3 show an embodiment of the negative actuation type electromagnetic brake according to the present invention, FIG. 1 is a longitudinal sectional view thereof, FIG. 2 is a front view of the yoke, and FIG. 3 is a guide member fixing part. FIG. In the figure, a negative actuation type electromagnetic brake 1 is equipped with a field indicated by the symbol 2 as a whole, and this field 2 is connected to a yoke 3.
and a back plate 4. The yoke 3 is formed entirely into an annular shape in front view by pressing a steel plate, and includes an annular groove 5 formed into an annular U-shaped cross section by deep drawing, and an annular mounting portion 6 continuing to the outer periphery of the annular groove 5. , and an annular spring receiving portion 7 continuing to the inner peripheral edge. The entire negative actuation type electromagnetic brake 1 is connected to the mounting hole 6 of the mounting portion 6.
It is fixed to a housing 8 as a device fixing part by a bolt (not shown) inserted in a. An electromagnetic coil 9 formed in an annular shape is wound around a coil bobbin 10 and housed in the annular groove 5, and the end surface of the bottom plate 5a of the annular groove 5 serves as a magnetic attraction surface 11 of the field 2.

12 is a side plate formed in a disc shape and fixed to the bottom plate 5a of the annular groove 5 with a plurality of bolts 13;
By being interposed between the side plate 12 and the field 2, a predetermined space is formed between the side plate 12 and the field 2, and the side plate 12 has a plane parallel to the magnetic attraction surface 11. In the space between the side plate 12 and the field 2, an annular armature 15 is slidably inserted with its plane facing the magnetic attraction surface 11. By engaging the holes with the collar 14, rotation is restricted and sliding is guided. In addition, bolt 13
The structure for fixing it to the bottom plate 5a will be described later. On the other hand, a shaft 16 is rotatably supported by a bearing on the housing 8 side, and a hub 17 is fixed to the tip of the shaft 16 with a key 18. 19 is a disk formed in a disk shape and interposed between the armature 15 and the side plate 12,
By spline fitting with the hub 17, the hub 1
7, and is formed to be slidable in the axial direction, and annular friction plates 20 and 21 are attached to both surfaces thereof. 22 is interposed between the armature 15 and the spring receiving part 7 of the yoke 3, and the armature 15 is attached to the magnetic attraction surface 1.
This is a braking spring that biases in a direction away from 1.

And, on the bottom plate 5a of the annular groove 5 of the yoke 3,
Two rows of slits 2 each formed in an arc shape
3 and 24 are provided by punching at intervals in the radial direction, and a plurality of arc-shaped slits 25 are formed in the portion of the armature 15 facing the magnetically attracting surface 11, which are formed in the slits on the yoke 3 side. 2
3 and 24, and are provided by punching so as to be out of phase with each other in the radial direction. That is, in the cross-sectional view of FIG.
4. With this configuration, the magnetic flux shown by the symbol Φ in the figure generated by the excitation of the electromagnetic coil 9 detours from the bottom plate 5a to the armature 15, returns to the bottom plate 5a, and detours to the armature 15 again, resulting in a double flux. flows through the path of

The back plate 4 is formed into an annular shape, and is press-fitted to close an opening of an annular groove 5 in which an electromagnetic coil 9 is housed.

In the present invention, as shown in FIG. 3, an inward protrusion 5c is formed by burring on the annular groove bottom plate 5a, and the screw hole 5d for the bolt 13, which serves as a guide member for the armature 15, is formed on the annular groove bottom plate 5a. It is drilled in. By doing this, the number of screw threads that are engaged with the threaded portion of the bolt 13 increases, so even if a large force is applied to the bolt 13 when the braking torque is large, the rotation of the armature 15 can be sufficiently restricted. There is no problem even if the yoke 3 is made of a thin steel plate.

The operation of the negative actuation type electromagnetic brake configured as above will be explained. When the electromagnetic coil 9 is excited, a magnetic flux Φ is generated. By providing the slits 23, 24 and the slit 25, which are out of phase with each other in the radial direction, in the bottom plate 5a of the annular groove 5 and the armature 15, the magnetic flux Φ is generated. As shown in the figure, the path detours around the armature 15 so as to reciprocate twice between the bottom plate 5a and the armature 15 using the slits 23, 24, and 25 as magnetic breakers. In this way, the magnetic flux Φ
When this occurs, the armature 15 resists the elastic force of the braking spring 22 and is attracted to the magnetic attraction surface 11 of the field 2, and the friction 20 and 21 on both sides of the disk 19 are released from pressure, allowing the disk 19 to rotate. , the shaft 16 rotates together with the disk 19 via the hub 17.

When the drive of the shaft 16 is released from this state and the electromagnetic coil 9 is demagnetized, the armature 15 is moved by the elastic force of the braking spring 22 to the magnetic attraction surface 11 of the field 2.
The disk 19 moves and the friction plates 20 and 21 on both sides of the disk 19 are pressed against each other.
9 is braked, the hub 17 stops, and the shaft 16
will also stop.

Negative action electromagnetic brake 1 that operates in this way
The entire yoke 3 is formed by deep drawing of the annular groove 5 and the slit 23, by pressing a steel plate.
Since it is formed by 24 punching processes, it is easy to manufacture and lightweight.

FIG. 4 is a longitudinal cross-sectional view of the upper half of the electromagnetic brake showing an embodiment of the invention of claim 2. In the invention, the outer side plate 5e of the annular groove 5 is connected to the bottom plate 5a at the corresponding part of the collar 14. The bolts 13 are cut and raised so that they are flush with each other, and the bolts 13 are inserted into through holes in the cut and raised portions and fixed with nuts. By doing this, the diameter of the disk 19 is not reduced to restrict the rotation of the armature 15, and the rotation of the armature 15 is sufficiently restricted.

In the above embodiment, an example was shown in which the disk 19 was spline-fitted to the hub 17, but these members could be made into an integral structure and the side plate 12
It is also possible to use a negative actuation type electromagnetic brake that does not require this. Further, in such a case, instead of the bolt 13 and the collar 14, a stud or the like with a male thread formed on one side may be used.

[Effect of idea]

As is clear from the above description, according to the present invention, there is provided a yoke made of a steel plate having an annular shape as a whole and having an annular groove for storing an electromagnetic coil and a slit formed in a concentric arc shape on the bottom plate of the annular groove; By providing the armature, which is supported so as to move forward and backward in the direction of the end surface of the bottom plate of the yoke, as a component of the negative action type electromagnetic brake, the entire yoke is manufactured by pressing a thin steel plate. Because it is lightweight and easy to handle,
Production costs can be reduced by simplifying the production process. In addition, by screwing and fixing the guide member that regulates the rotation of the armature into a protrusion formed on the annular groove bottom plate, or by fixing this guide member to the outer side plate formed by cutting and raising the yoke, Even when the braking torque is large, the rotation of the armature can be sufficiently regulated, and the durability of the guide member fixing part is improved, making it possible to obtain a thin, lightweight, and high braking torque negative actuation type electromagnetic brake. When the guide member is fixed to the outer side plate, the diameter of the disk will not be reduced due to the fixation of the guide member.

[Brief explanation of the drawing]

1 to 4 show an embodiment of the negative actuation type electromagnetic brake according to the present invention, FIG. 1 is an expanded longitudinal sectional view thereof, FIG. 2 is a front view of the yoke, and FIG. 3 is a guide member fixing part. FIG. 4 is an enlarged longitudinal sectional view of the upper half of a negative operation type electromagnetic brake showing an embodiment of the invention according to claim 2. DESCRIPTION OF SYMBOLS 1... Negative action electromagnetic brake, 2... Field, 3... Yoke, 5... Annular groove, 5a... Bottom plate, 5c... Protrusion, 5d... Screw hole, 5e... Outer side plate, 9... Electromagnetic coil, 11...magnetic adsorption surface, 15...armature.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A yoke made of steel plate material having an annular shape as a whole and having an annular groove for storing an electromagnetic coil and a slit formed in a concentric arc shape on the bottom plate of the annular groove, and this yoke. an armature supported so as to be freely advanced and retracted in a direction toward and away from the end surface of the bottom plate, and a guide member for regulating rotation of the armature is screwed and fixed to a protrusion formed on the bottom plate. Electromagnetic brake. (2) A yoke made of a steel plate material having an annular shape as a whole and having an annular groove for storing an electromagnetic coil and a slit concentrically formed in the bottom plate of the annular groove, and a perspective direction of the yoke with respect to an end surface of the bottom plate. A negative actuation type electromagnetic brake, comprising an armature that is supported to move forward and backward, and a guide member for regulating rotation of the armature is fixed to an outer side plate formed by cutting and raising the yoke.