JPH07253130A - Nonexcitation operation type electromagnetic brake - Google Patents

Abstract

PURPOSE:To improve the assemblability of a nonexcitation operation type electromagnetic brake capable of automatic gap regulation. CONSTITUTION:A gap holding shaft 12 is formed on a hollow shaft whose both ends are severally inserted in the guide hole 7a of an armature 7 and the guide hole 8b of a pressure receiving plate 8, and a gap (g) between the second ring holder 13 press-fitted on the gap holding shaft 12 and an engaging plate 14 fixed to the armature 7 is set up so as to be equal to a gap G between a field core 4 and the armature 7 in a nonexcitation state. In addition, a flange part 12a is formed on the gap holding shaft 12, and put upon the disc-shaped outside flange 9a of the first ring holder 9 press-fitted on the gap holding shaft 12, and fixed to the pressure receiving plate 8 through a fixing plate 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-excitation actuated electromagnetic brake capable of automatic clearance adjustment.

[0002]

2. Description of the Related Art An unexcited actuation type electromagnetic brake supports a pressure receiving plate in front of a field core having an electromagnetic coil installed therein through a plurality of guide shafts fixed to the field core, and An armature supported by a guide shaft is arranged between the core and the pressure receiving plate so as to be movable only in the axial direction. Then, the disc mounted on the braked shaft is interposed between the armature and the pressure receiving plate,
The disc is braked by a braking spring that presses the armature toward the pressure receiving plate. Also, by magnetically attracting the armature to the field core against the pressing force of the braking spring,
It has a structure for releasing the braking of the disc and the braked shaft on which the disc is mounted.

In the non-excitation actuated electromagnetic brake having such a structure, the gap formed between the field core and the armature in the non-excitation state increases due to wear of the disc, the armature frictionally engaged with the disc and the pressure receiving plate. As a result, the braking release characteristic of exciting the field core and magnetically attracting the armature against the spring force of the braking spring deteriorates, so the non-excitation actuated electromagnetic type that enables automatic adjustment of the gap. Various brakes have been proposed.

One of them is Japanese Utility Model Application 60-1703.
There is a "rotating electric machine with a brake" proposed in the specification and drawings at the time of filing of No. 55 (Actual No. 62-81736).
In the non-excitation actuated electromagnetic brake described as an example in this specification, a stepped through hole having a large-diameter side opening is formed on the pressure receiving plate on the side opposite to the disk, and the stepped hole is inserted. The gap holding shaft is supported by the pressure receiving plate via the ring holder, and a head is provided at the tip protruding from the through hole of the armature of the gap holding shaft to the field core side, and there is no excitation between the head and the armature. In this structure, a gap having the same size as the gap between the armature and the field core in the state is formed. In addition, another ring holder is also placed in another stepped guide hole of the pressure receiving plate, and the pressure is received via the other ring holder to the guide shaft that is fixed to the field core and supports the entire device on the bracket. The structure is such that the board is supported.

Therefore, in the non-excitation actuated electromagnetic brake, the armature, the disc and the pressure receiving plate are pressed to the bracket side by the braking spring in the non-excitation state, but the pressure receiving plate is pressed to the bracket by the ring holder. Since the movement of the disk is restricted, the disk and the braked shaft on which the disk is mounted are braked. Also, when the gap between the field core and armature increases due to wear of the disk, the armature hits the head of the gap holding shaft when in the excited state, and the pressure receiving plate accompanies the magnetic attraction movement of the armature to the field core. Since the gap is also increased and drawn, the gap can be automatically adjusted.

On the other hand, other non-excitation actuated electromagnetic brakes are disclosed in Japanese Utility Model Application No. 62-72000 (Saikai No. 63-1).
No. 80746) There is an "electromagnetic brake device with an auto gap mechanism" proposed in the specification at the time of application and in the drawings.
The non-excitation actuated electromagnetic brake described as an example in this specification has a clearance holding shaft which is fixed to the armature and is inserted into a through hole formed in the pressure receiving plate. A wave spring, a flat ring, a ring holder, and a pressing plate are sequentially fitted to the tip protruding from the outside of the plate. And
A ring holder is press-fitted onto the clearance holding shaft, and an outer edge of the ring holder is prevented from coming off by a pressing plate fixed to a pressure receiving plate. In addition, the guide shaft fixed to the field core is provided so as to project outward from the guide hole of the pressure receiving plate,
Another ring holder press-fitted to the tip of the guide shaft is retained by a pressing plate via a flat wheel.

In the non-excitation actuated electromagnetic brake having such a structure, when the clearance between the field core and the armature increases, when the armature magnetically moves to the field core, the increased wear causes the clearance holding shaft and the ring. Since the armature pulls the pressure receiving plate via the holder, and another ring holder on the guide shaft is also moved by the pressing plate along with the pulling, the gap can be automatically adjusted.

[0008]

In the conventional non-excitation actuated electromagnetic brake capable of automatic clearance adjustment, a clearance equal to the clearance in the non-excited state of the field core and the armature is provided between the armature and the head of the clearance holding shaft. Alternatively, there is a difference in that it is configured between the pressure receiving plate and the ring holder of the gap holding shaft, or that each ring holder is hooked in the stepped through hole of the pressure receiving plate or is engaged with the pressing plate fixed to the pressure receiving plate. However, the same effect can be expected in that the gap can be automatically adjusted. However, these non-excitation actuated electromagnetic brakes have a structure in which a ring holder for pulling the pressure receiving plate by the armature along with the magnetic attraction movement of the armature is directly press-fitted onto the clearance holding shaft, which facilitates assembly of the device. There was a need for improvement.

That is, as described on page 11, lines 9 to 10 of the specification at the time of filing of Japanese Utility Model Application No. 60-170355 and in FIG. Improvement was desired. In this invention,
An object is to improve the assemblability of a non-excitation actuated electromagnetic brake capable of automatic clearance adjustment.

[0010]

In order to achieve such an object, in the non-excitation actuated electromagnetic brake of the present invention, as a first invention, the field core is alternately erected in front of the field core at circumferential intervals. It has a plurality of first and second guide shafts installed, and each guide shaft has a structure in which it is inserted into a guide hole and a through hole formed in the armature and the pressure receiving plate, and the first guide shaft receives pressure. The first ring holders that prevent the plates from coming off are individually press-fitted. Further, a clearance holding shaft having a hollow shaft shape with both ends facing the through hole of the armature and the pressure receiving plate was fitted to the second guide shaft, and the clearance holding shaft was fixed to the pressure receiving plate. The clearance between the second ring holder press-fitted to each clearance holding shaft and the engaging plate fixed to the armature is set to be equal to the clearance between the field core and the armature in the non-excited state. .

As a second invention, the first guide shaft in the first invention is omitted, and a plurality of guide shafts corresponding to the second guide shaft are provided with a first ring holder for preventing the pressure receiving plate from coming off. The structure is characterized in that the first ring holder and the second ring holder are arranged coaxially by being press-fitted into.

[0012]

In the non-excitation actuated electromagnetic brake, the armature is pressed by the braking spring toward the pressure receiving plate via the disc, so that the disc and the braked shaft on which the disc is mounted are braked. When the armature is magnetically attracted to the field core against the pressing force of the braking spring, the braking of the disc and the braked shaft is released. When the disk wears due to such repeated operation, the gap between the field core and the armature in the non-excited state increases, and the magnetic resistance in the magnetic circuit of the electromagnetic coil installed in the field core increases and braking Although the release characteristic deteriorates, when the armature magnetically moves to the field core, the gap is automatically adjusted by pulling the pressure receiving plate through the second ring holder and the gap holding shaft by the amount of the increase in the gap. .

[0013]

1 to 5 show a non-excitation actuated electromagnetic brake according to an embodiment of the present invention. FIG. 1 is a front view, FIG. 2 is a sectional view taken along the line AA of FIG. 1, and FIG. 1 is a sectional view taken along line BB of FIG.
FIG. 4 is an enlarged view of an essential part around the first ring holder in FIG.
FIG. 3 is an enlarged view of a main part around the second ring holder in FIG. 1. Hereinafter, embodiments will be described with reference to these drawings.

A non-excitation actuated electromagnetic brake 1 is an end bracket 2 of a motor which is a drive source for general industrial machines and the like.
It is mounted so as to brake the braked shaft 3 protruding from the. Reference numeral 4 is a field core fixed to the end bracket 2 by a mounting screw (not shown) that is inserted from the mounting screw hole 4a and screwed into the end bracket 2.
The electromagnetic coil 5 is integrally fixed to the inside of the annular groove with an insulating resin and provided therein. Further, on the front surface of the field core 4 (the magnetic pole surface of the electromagnetic coil 5), a plurality of first guide shafts 6 (three in the 120 ° equidistant positions in the embodiment) are arranged at circumferential intervals. The first guide shafts 6 are erected by screwing and fixing the screw parts, and the first guide shafts 6 are formed in the armature 7 and the pressure receiving plate 8 which are provided in front of the field core 4, respectively.・ It is inserted through 8a. Then, a first ring holder 9 having a substantially disc spring shape is press-fitted to each tip of the first guide shaft 6 protruding from the pressure receiving plate 8, and the disk-shaped first ring holder 9 has a disk shape. The outer edge portion 9a is integrally fixed to a fixing plate 10 having a rectangular shape in plan view having an annular portion having an L-shaped cross section. The fixing plate 10 is fixed to the pressure receiving plate 8 with a screw, and the first ring holder 9
The fixing plate 10 can be constructed as a single piece. Further, a pair of chamfered portions 6 a into which a tool for screwing the first guide shaft 6 into the field core 4 is fitted is formed at the tip of the first guide shaft 6.

In this embodiment, a plurality of second guide shafts 11 (three at equidistant positions of 120 degrees in the embodiment) are provided on the front surface of the field core 4 at circumferentially spaced intervals. Are erected by being screwed together and fixed, and are arranged alternately with the first guide shafts 6. Reference numeral 11a is a pair of chamfered portions formed in the same manner as the chamfered portion 6a of the first guide shaft 6. Each second guide shaft 11 has
A plurality of armatures 7 and pressure receiving plates 8 (in the embodiment, 12
Guide holes 7a, 8 drilled at 3 positions each at 0 °
It is inserted into a hollow shaft-shaped gap holding shaft 12 fitted so that both ends thereof face into through holes 7b and 8b different from a. The gap holding shaft 12 has a flange portion 12a formed at the end portion on the pressure receiving plate 8 side, and the flange portion 12a is formed through the through hole 8b of the pressure receiving plate 8.
The counterbore surface formed in the opening is fitted and fixed to the pressure receiving plate 8 with a pair of screws.

A second ring holder 13 having a substantially disc spring shape is press-fitted into each clearance holding shaft 12. Further, in the second ring holder 13, the press-fitting fitting portion to the clearance holding shaft 12 faces the counterbore surface formed in the opening of the through hole 7b of the armature 7, and the disk-shaped outer edge portion 13a receives the pressure of the armature 7. It is in contact with the surface on the plate 8 side. And this second
A gap g equal to the gap G between the field core 4 and the armature 7 in the non-excited state (see FIG. 5) is set between the outer edge portion 13a of the ring holder 13 and the engaging portion 14a of the engaging plate 14. There is. The engagement plate 14 has a shape similar to that of the fixed plate 10, and has a circular plate portion having an L-shaped cross section formed by press-pressing on a part of a steel plate that is rectangular in plan view.
It is fixed to the armature 7 with a pair of screws.

Further, in this embodiment, a disc 15 having a pair of linings 15a fixed thereto is interposed between the armature 7 and the pressure receiving plate 8, and the disc 15 is mounted on the braked shaft 3 of the motor. The hub 16 is key-fitted and is retained by a retaining ring (not shown) so as to be spline-fitted with the hub 16. And field core 4
Each braking spring 1 individually inserted into a plurality of spring holes 4b (three, for example, at circumferentially equidistant positions, see FIG. 3) formed in the
The armature 7 is pressed against the pressure receiving plate 8 side through the disk 15 by the pressing force of 7. The reference numeral 18 in FIG.
Guide pins are provided upright on the front surface of the field core 4 at intervals in the circumferential direction, and are individually inserted and fixed in through holes formed in the armature 7 in plural numbers.

In the non-excitation actuated electromagnetic brake 1 having the above-described structure, in the non-excitation state as shown in FIGS. 2 and 3, the braking spring 17 causes the armature 7 to press the pressure receiving plate 8 side through the disc 15. Therefore, the disk 15 and the braked shaft 3 on which the disk 15 is mounted are braked and held stationary. Here, when the electromagnetic coil 5 of the field core 4 is energized to be in an excited state, the armature 7 becomes a braking spring 17
Since the magnetic field is magnetically attracted to the field core 4 against the pressing force of and is separated from the disk 15, the braking of the disk 15 and the braked shaft 3 on which the disk 15 is mounted is released.

When the lining 15a of the disk 15 is worn and the gap G between the field core 4 and the armature 7 becomes large due to the repetition of such operations, the magnetic resistance in the magnetic circuit of the electromagnetic coil 5 also becomes large and braking is performed. In this embodiment, when the armature 7 is magnetically attracted to the field core 4, the engaging plate 14 fixed to the armature 7 is brought into contact with the second ring holder 13 so that the releasing characteristic is deteriorated. Since the pressure receiving plate 8 is pulled apart by the magnetic attraction movement of the armature 7 via the two-ring holder 13 and the gap holding shaft 12, the gap G is automatically adjusted.

Next, a non-excitation actuated electromagnetic brake according to another embodiment of the present invention will be described. FIG. 6 is a cross-sectional view of only the upper half, and the same components as those in the previous embodiment are designated by the same reference numerals, and the duplicated description will be omitted. In this non-excitation actuated electromagnetic brake 19, the first guide shaft 6 in the previous embodiment is omitted. Then, the first ring holder 9 serving as a retaining member for the pressure receiving plate 8 is press-fitted onto the second guide shaft 11 in the previous embodiment. Further, the disc-shaped outer edge portion 9a of the first ring holder 9 is overlapped with the flange portion 12a of the gap holding shaft 12, and is fitted in the counterbore surface formed in the opening of the through hole 8b of the pressure receiving plate 8. There is. Then, the ring-shaped fixed plate 2 fixed to the pressure receiving plate 8
It is locked by 0.

The non-excitation actuated electromagnetic brake 19 having the above-described structure operates in the same manner as the non-excitation actuated electromagnetic brake 1, and the gap G between the field core 4 and the armature 8 is automatically adjusted.

In the above embodiment, the pressure receiving plate 8 is prevented from coming off by the first ring holder 9 having a substantially disc spring shape, but it is shown in the enlarged view of the main parts around the first ring holder in FIGS. 7 and 8. As described above, the pressure receiving plate 8 is prevented from coming off by the first ring holder 19 having the conical peripheral surface 19a fitted to the conical counterbore surface 8c formed in the guide hole 8a of the pressure receiving plate 8 and the slit 19b. May be. Also, the first ring holder 1
In order to regulate the backward movement of 9 the compression coil spring 21 that is prevented from coming off by the retaining ring 20 and the slit that is press-fitted to the first guide shaft 6 and screwed to the pressure receiving plate 8 like the first ring holder 9. A retaining ring 22 having 22a may be provided.
With such a retaining structure, when the pressing force of the braking spring 17 is received, the first ring holder 19 is firmly press-fitted into the first guide shaft 6, so that the pressure receiving plate 8 is detached. The stop can be ensured.

[0023]

In such a non-excitation actuated electromagnetic brake, since the hollow shaft-shaped clearance holding shaft is constructed as the first invention, the first guide shaft is inserted into the guide holes of the armature and the pressure receiving plate, and the field core is inserted. After adjusting the clearance between the field core and the armature by press-fitting and fitting the first ring holder onto the first guide shaft, insert the second guide shaft into the clearance holding shaft and screw into the field core. Since the assembly is completed only by fixing and fixing, the productivity of the non-excitation actuated electromagnetic brake can be improved.

In the second aspect of the invention, the first ring holder and the second ring holder / gap holding shaft are arranged on the same guide shaft, so that the productivity of the non-excitation type electromagnetic brake can be further improved. Along with this, it can be provided at low cost.

[Brief description of drawings]

FIG. 1 is a front view of a non-excitation actuated electromagnetic brake that is an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG.

FIG. 4 is an enlarged view of a main part around a first ring holder in FIG.

FIG. 5 is an enlarged view of a main part around a second ring holder in FIG.

FIG. 6 is a sectional view of only the upper half of the non-excitation actuated electromagnetic brake according to another embodiment of the present invention.

FIG. 7 is an enlarged view of a main part around a first ring holder that is another embodiment of the present invention.

FIG. 8 is an enlarged view of a main part around a first ring holder that is another embodiment of the present invention.

[Explanation of symbols]

 4 field core 5 electromagnetic coil 6 first guide shaft 7 armature 8 pressure receiving plate 9 first ring holder 11 second guide shaft 12 gap holding shaft 13 second ring holder 14 engaging plate 15 disc 17 braking spring

Claims (2)

[Claims] 1. A field core in which an electromagnetic coil is installed, a plurality of first guide shafts standing upright in front of the field core at circumferential intervals, and the first guide shafts are individually provided. A pressure receiving plate having a guide hole to be inserted,
A first ring holder press-fitted to each tip of the guide shaft projecting outward from the guide hole of the pressure receiving plate to allow only the movement of the pressure receiving plate to the field core side; the field core; An armature provided between the pressure receiving plate and a plurality of guide holes through which the guide shafts are individually inserted, and individually fixed in a plurality of through holes different from the guide holes of the pressure receiving plate. A plurality of hollow shaft-shaped gap holding shafts, each tip of which faces a plurality of through holes different from the guide holes of the armature, and are press-fitted into the gap holding shafts to the pressure receiving plate side. Of the second ring holder, a hooking plate fixed to the armature and having a hooking portion facing each of the second ring holders with a predetermined gap, and a circumference of the front surface of the field core. Direction spacing A plurality of second guide shafts that are erected upright and are individually inserted into the gap holding shafts, a disc that is mounted between the armature and the pressure receiving plate and that is mounted on the braked shaft, and the discs And a braking spring for pressing the armature to the pressure receiving plate side, and a gap between the field core and the armature in a non-excited state, a gap between the second ring holder and the engaging plate are set to be equal to each other. Non-excitation actuated electromagnetic brake. 2. A field core in which an electromagnetic coil is provided, a plurality of guide shafts standing upright in front of the field core at circumferential intervals, and a guide into which these guide shafts are individually inserted. A pressure receiving plate having a hole formed therein and a pressure receiving plate press-fitted to each tip of the guide shaft projecting outward from a guide hole of the pressure receiving plate to permit only movement of the pressure receiving plate to the field core side. 1 ring holder, an armature having a plurality of guide holes formed between the field core and the pressure receiving plate and having the guide shafts individually inserted therein, and individually fixed in the guide holes of the pressure receiving plate A plurality of gap holding shafts each having a hollow shaft shape with each tip facing the guide hole of the armature and fitted into the guide shafts, and press-fitted into each of the gap holding shafts to the pressure receiving plate side. Allowable to move Second ring holders, a hooking plate fixed to the armature and having a hooking portion facing each of the second ring holders with a predetermined gap, and an interposing member between the armature and the pressure receiving plate. A disc mounted on the braked shaft, and a braking spring that presses the armature toward the pressure receiving plate via the disc,
A non-excitation actuated electromagnetic brake, wherein a gap between the field core and the armature and a gap between the second ring holder and the engaging plate in a non-excited state are set to be equal.