JPS628661Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] In this invention, an armature placed directly opposite a fixed member through a disk is pressed toward the fixed member by the pressing force of a compression coil spring. This invention relates to a reverse-actuating electromagnetic brake that obtains braking force by doing so.

[Conventional technology]

Conventionally, in this type of reverse action electromagnetic brake,
As an example of this is shown in FIG. Annular or annularly arranged friction plates 6, 6 are fixed to both end surfaces near the periphery of an axially flexible plate spring-shaped disk 5 concentrically caulked and fixed to the flange 4A, and these friction plates are The mounting plate 7 as a fixing member is fixed to the end face of the rotating machine 1 with bolts, and the mounting plate 7 receives the elastic pressing force of the compression coil springs 8 provided at a plurality of locations.
Rotation of the rotating shaft 2 is prevented by pinching it with the armature 9 which is pressed in the direction.

The armature 9 that operates as a brake member is supported in front of the mounting plate 7 at a distance from the mounting plate 7 by a plurality of bolts 10 as connecting members arranged on the same circumference. When magnetically attracted to an annular field core 12 fixed to a bolt 10 with nuts 11, 11, the disk 5 to which the friction plate 6 is fixed is released, causing the electromagnetic brake to lose its braking function. The armature 9 has each of the bolts 10
A hole 15 is provided for inserting a collar 14 into which the collar 14 is fitted and secured with a nut 13.

The field core 12 has a compression coil spring 8
When a voltage is applied to an electromagnetic coil 17 built into the field core, a magnetic flux Φ is generated and the armature 9 is magnetically attracted.

[Problem that the invention attempts to solve]

In the conventional reverse-actuating electromagnetic brake having the above-described structure, as described above, the armature 9, which has become de-energized by stopping the supply of electricity to the electromagnetic coil 17, is integrated with the rotating shaft 2 which is rotating due to inertia. It comes into pressure contact with a friction plate 6 fixed to the disc 5, and brings it into frictional contact with the mounting plate 7 to perform braking, so at that time,
A slight amount of twisting occurs between the friction plate 6, that is, the rotating shaft 2.

On the other hand, as described above, when the armature 9 is attracted to or separated from the field core 12, it moves in the axial direction using the collar 14 externally fitted on the bolt 10 inserted into the hole 15 as a guide. Therefore, since a certain degree of dimensional difference is naturally provided between the inner diameter of the hole 15 and the outer diameter of the collar 14, when the above-mentioned rotation occurs, the inner circumferential surface of the hole 15 on the collar 14 collide and generate noise and vibration.

For example, if the rotating machine 1 is a rotating machine for a camera, this vibration will cause shutter shake and the noise will be unpleasant to the ears.

[Means for solving problems]

Based on the above-mentioned viewpoints, this invention provides a reverse-actuating electromagnetic brake in which there is no risk of the armature colliding with the bolt, which is a connecting member, and in particular the collar, causing noise and vibration due to rotation. A disk that rotates together with the shaft, an armature disposed directly opposite the fixed member through the disk, a compression coil spring that presses the armature toward the fixed member, and a compression coil spring that presses the armature toward the fixed member, and A field core with a built-in electromagnetic coil that magnetically attracts the armature in a direction to pull the armature away from the disk, and a connecting member that integrally connects the field core and the fixing member, and the connecting member guides the axial movement of the armature. The reverse action electromagnetic brake that supports the armature as a member is characterized in that the armature is fixedly supported by the connecting member via a leaf spring so as to be movable only in the axial direction.

〔Example〕

Next, the reverse-actuating electromagnetic brake of this invention will be explained by way of examples with reference to the drawings.

FIG. 2 shows an example of the reverse action electromagnetic brake of this invention in a longitudinal sectional side view. Further, FIG. 3 shows a partially cutaway front view of the main structure of this invention as a sectional view taken along the line of FIG. 2. In addition,
This embodiment differs from the conventional reverse-actuating electromagnetic brake shown in FIG. 1 only in the armature support structure, so the same reference numerals as in FIG. 1 are used here for the same members in the structure other than the armature support structure. and use the previous explanation. As shown in the drawings, the reverse action electromagnetic brake 18 of this embodiment includes:
The collar 14' fixed to the mounting plate 7 is shortened, and one end of the arc-shaped leaf spring 19 is fitted into the bolt 10 between the collar 14' and the nut 13, and the other end is fixed to the armature. It is fixed at a predetermined position on the back side of 9 with bolts 20.

The leaf springs 19 are usually three pieces arranged at equiangularly divided positions on the back surface of the armature, consist of circular arcs concentric with the armature 9, and are fixed concentrically near the outer peripheral edge of the armature 9.

As is clear from FIGS. 2 and 3, the armature 9 has an arcuate notch 22 at the outer peripheral edge 3 for dodging the bolt 10 and the bolt 21 that fixes the mounting plate 7 to the end face of the rotating machine 1. It is provided at a certain location.

In the reverse action electromagnetic brake 18 of this invention having the above-described configuration, when a voltage is applied to the electromagnetic coil 17 from the state shown in FIG. Magnetic adsorption to.

When the armature 9 is magnetically attracted to the field core 12, the pressing force applied to the friction plates 6, 6 in the direction of the mounting plate 7 is removed, so the friction plates 6, 6
The rotary shaft 2, which is integral with the disk 5 to which it is fixed, becomes free.

Conversely, when the rotating shaft 2 enters the braking state from the driving state, the drive power to the rotating machine 1 is usually cut off, and the rotating shaft 2 enters the idling state. If the power supply circuit of the electromagnetic coil 17 is connected in series with this drive power supply circuit, or if a relay switch that opens simultaneously when the drive power supply circuit of the rotating machine 1 is opened is inserted in the power supply circuit of the electromagnetic coil 17, the rotating shaft 2 becomes idling, and at the same time armature 9 touches friction plate 6.
is pressed against the mounting plate 7 to stop the rotation of the rotating shaft 2.

At this time, the armature 9 cannot move in the rotational direction because it is connected to the mounting plate 7, which is a fixed member, through the leaf spring 19 and the bolt 10, which is a connecting member. Since no rotation occurs, no collision occurs between the armature and the connecting member.

[Effect of idea]

As is clear from the above explanation, in the reverse action electromagnetic brake of this invention, when the armature presses the friction plate against the fixed member, the armature is prevented from moving against the connecting member by the leaf spring that supports the armature on the connecting member. This has the excellent advantage that no noise or vibration is generated between the armature and the connecting member because it does not cause sagging.

[Brief explanation of the drawing]

FIG. 1 is a vertical side view showing an example of a conventional reverse-acting electromagnetic brake, FIG. 2 is a vertical side view showing an embodiment of the reverse-acting electromagnetic brake of this invention, and FIG.
FIG. 2 is a front view with a part of the figure-line view portion removed. In the drawings, 1...rotating machine, 2... rotating shaft,
4... Brake hub, 4A... Flange, 5...
Disc, 6...Friction plate, 7...Mounting plate, 8...
Compression coil spring, 9... Armature, 10...
Bolt, 12...Field core, 14, 14'
... Collar, 15 ... Stupid hole, 17 ... Electromagnetic coil, 18 ... Reverse action electromagnetic brake of this invention, 1
9... Leaf spring, 20, 21... Bolt, 22...
Notch, Φ...magnetic flux.

Claims (1)

[Scope of utility model registration request] A disk that rotates together with the rotating shaft, an armature disposed directly opposite the fixed member through the disk, a compression coil spring that presses the armature toward the fixed member, and a compression coil spring that resists the pressing force of the compression coil spring. A field core with a built-in electromagnetic coil that magnetically attracts the armature in a direction to pull the armature away from the disk, and a connecting member that integrally connects the field core and the fixed member, and the connecting member prevents the armature from moving in the axial direction. In the reverse-actuating electromagnetic brake that supports the armature as a guide member, the armature is fixedly supported on the connecting member via a leaf spring so as to be movable only in an axial direction. .