JPS5818536B2 - Automatic gap adjustment device for electromagnetic brakes - Google Patents

Abstract

PURPOSE:To improve the supporting disc of a solenoid brake or the like in responsiveness and permit a reliable automatic gap regulation by facing the supporting disc to hold an armature attracted by an electromagnet to said electromagnet in the direction of its magnetic line of force so that said disc is placed in the magnetic flux. CONSTITUTION:On the shaft of a collar 6, a supporting disc 7 having a diameter approximately equal to that of a flange 6a is axially movably provided facing to an electromagnet 4 in the direction of its magnetic line of force through a plate spring S1. Then, an armature 10 having a given gap (g) between a stator 3 provided with the electromagnet 4 and a friction plate 5 is axially movably provided through a ring-shaped spring S2 so that the spring force of the spring S1 is smaller than the electromagnetic attraction force acting upon the armature 10 but larger than the spring force of the spring S2. Thereby, the gap between the friction plate 5 and the armature 10 can be kept proper, so that a reliable automatic gap regulation can be expected under a constantly stable condition.

Description

[Detailed description of the invention] The present invention relates to an automatic gap adjustment device for an electromagnetic brake.

Referring to FIG. 6 showing a conventional example, the conventional electromagnetic brake is fitted onto the rotating shaft 22 with the engagement of a key 42 by excitation of an electromagnet 24 housed in a stator 23 attached to an end bracket 21. The armature 30 on the collar 26 is pulled against the elasticity of the circular leaf spring S, and the rotation of the rotating shaft 220 is stopped by contact friction between the armature 30 and the friction plate 25 on the stator 23. However, in this conventional electromagnetic brake, a collar 27 abutting against the stepped portion 43 of the rotary shaft 22 and several washer-like shims 41 abutting against the collar 27 are attached to the rotary shaft 22 in advance.
2, the end of the collar 26 is placed on the rotating shaft with the end in contact with the shim 41, and the collar 26 is fixed on the shaft 22 by screwing in the set screw 29 that is threaded into the screw hole 40. The end face of the collar 26 is limited by a fixing collar 28. If the friction plate 25 wears out due to constant use of the electromagnetic brake and the gap g widens beyond the allowable limit, the shim 41 can be removed. The gap between the electromagnetic brakes was adjusted by removing the friction plate 25 according to the amount of wear and moving the collar 26 forward toward the stator by the thickness of the removed shim 41.

However, in this conventional gap adjustment, in order to remove the shim 41, it is necessary to disassemble the entire device and remove the fixing collar 28 and collar 26 from the rotating shaft 22. It is necessary to reassemble the entire device by fitting and fixing the collar 26 and the fixing collar 28 onto the shaft 22 again, and the gap adjustment of the conventional electromagnetic brake lacks simplicity.

Therefore, an object of the present invention is to provide an automatic gap adjustment device that automatically adjusts the gap on the friction engagement surface of a friction transmission mechanism such as an electromagnetic brake, thereby solving the inconveniences of conventional gap adjustment. .

To explain the configuration of the present invention with reference to the illustrated embodiments, 1
is the end bracket of the motor, 2 is the rotation axis of the motor, 3
numeral 4 is an electromagnet built into the stator, and numeral 5 is a friction plate attached to the magnetic pole surface of the stator.

Reference numeral 6 denotes a boss with an outer flange 6a fixed on the rotating shaft 2. On the shaft of the boss, a support disk 7 having approximately the same diameter as the flange portion 6a is attached to the electromagnet 4 in the direction of the magnetic field lines of the electromagnet 4. A ring-shaped leaf spring S having elasticity in the axial direction faces each other.
1 so as to be slidable in the axial direction.

Then, the opposing edges of the support disk 7 and the flange portion 6a of the collar are tapered to form a substantially square-shaped circumferential groove 8, and an endless coil spring 9 is tensioned in the circumferential groove 8. Keep it on.

Reference numeral 10 denotes an armature disposed with a constant gap g1 between the friction plate 5, and the armature is slidably connected to the inner surface of the support disk 7 via a ring-shaped leaf spring S having elasticity in the axial direction. In this case, among the bolts 11 that fix the leaf spring S2 to the armature 10 and the support disk 7 alternately on its circumferential surface, the bolts 1. ,,1 ,,,a to the other bolt 1
Unlike 1b, it has a stepped structure with a head 13.

The support disk 7 has a large diameter stepped portion 1 on the flange portion 6a side.
A through hole 12 having a diameter 2a is provided.

The static pole t11a is inserted into the through hole 12 from the flange portion 6a side and fixed to the armature 10, thereby fixing the ring-shaped leaf spring S to the armature 10.

The head 13 has a larger diameter than the through hole 12, but the stepped portion 12a
smaller than the diameter of.

The gap g with respect to the stepped portion 12a in the non-operating state
They are designed to face each other with a gap g2 equal to 1.

In the above configuration, the spring force of the leaf spring 1S is smaller than the electromagnetic attractive force acting on the armature 10, and the spring force of the leaf spring S is smaller than the electromagnetic attraction force acting on the armature 10.
Adjust the spring force so that it is greater than the spring force in step 2.

Regarding the coil spring 9 in the V-shaped circumferential groove 8, although the coil spring is not pushed out of the groove by the return force of the plate spring S1, the support disk 7 and the armature are 10 is applied to the stator 3 side.

To explain the present invention in detail, FIGS. 1 and 2 show a state in which the electromagnet is de-energized and braking has never been applied.

At this time, the armature 10 is pulled toward the support disk 7 by the return force of the leaf spring S2, and there is a gap g1 between it and the friction plate 5.
is formed.

This gap g1 is between the support disk 7 and the stud bolt 11.
It is equal to the gap g2 provided between a.

When the electromagnet is excited, the armature 10 is attracted toward the stator 3 against the force of the leaf spring S2, and the rotating shaft is braked by contact friction with the friction plate 5.

At this time, as shown in FIG. 4, the spring force of the leaf spring S1 is smaller than the electromagnetic attraction force acting on the armature 10, but
The spring force of leaf spring S2 is adjusted to be smaller than that of leaf spring S1, so in the end, leaf spring S1 remains stationary and leaf spring S2
is pulled toward the stator 3, creating a gap g3 between the back surface of the armature 10 and the support disk 70, which is equal to the gap g2.

When the friction plate 5 wears out during use, the armature 10 first
As before, the stud bolt 1 is activated by excitation of the electromagnet.
Until the head of 1a comes into contact with the support disk 7, it is sucked and moved toward the stator side against the leaf spring S2.

Next, when the armature 10 is further moved toward the stator side against the leaf spring S1 by a distance corresponding to the amount of wear of the friction plate 5 by the electromagnetic attraction force, the stud bolt 1
The support disk 7 connected to the armature 10 via 1a is also forcibly moved by the same distance toward the stator,
The distance from the fixed flange portion 6a increases.

As a result, the coil spring 9 stuck in the V-shaped circumferential groove 8 contracts radially inward, and the fixed flange portion 6
a and the supporting disk 70, so when the next excitation is cut off, the armature 10 moves by a distance gl toward the side opposite to the stator due to the leaf spring S2.

At this time, the support disk 7 remains in the same position, so that exactly the same condition as before wear is reproduced at that position.

In the state where the excitation is cut off as in the above, a constant gap g1, which is equal to the gap g2 between the static pole t11a and the support disk 7, is always maintained between the friction plate 5 and the armature 10.

In the present invention, as described above, the support disk 7 holding the armature 10 attracted by the electromagnet 4 is arranged to face the electromagnet 4 in the direction of the magnetic field line of the electromagnet 4, and the support disk 7 is placed in the magnetic flux. , the responsiveness of the support disk 7 during gap adjustment is extremely good, and reliable automatic gap adjustment can be expected.

Further, the coil spring 9 that automatically maintains the gap between the friction plate 5 and the armature 10 at a set value is stuck in a circumferential groove 8 located axially above the friction plate 5. The dust produced by the wear of the coil spring 5 does not accumulate in the circumferential groove and has no adverse effect on the spring action of the coil spring 9, so that the gap can be adjusted reliably in a stable condition at all times.

The supporting disk 7 can be made of either magnetic or non-magnetic material, but if necessary, non-magnetic material can be used to ensure reliable operation.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, in which Fig. 1 is a longitudinal sectional view showing the structure of an electromagnetic brake, Fig. 2 is an enlarged view of the main part of Fig. 1, and Fig. 3 shows the installation of a ring-shaped leaf spring. FIGS. 4 and 5 are explanatory diagrams showing the state, FIGS. 4 and 5 are explanatory diagrams of the operation, and FIG. 6 is a partial vertical cross-sectional view of a conventional electromagnetic brake. Explanation of symbols, 1...Motor end bracket, 2.
... Rotating shaft of motor, 3... Stator, 4... Electromagnet, 5... Friction plate, 6... Boss, 6a... Flange portion, 7... Support disk, 8...・Circumferential groove, 9... Coil spring, 10... Armature, 11a...
・Stat bolt, 11b...Bolt, gl 2g2
2g3...Gap, Sl. S2...plate spring.

Claims (1)

[Claims] 1. In an electromagnetic brake, a stator 3 having a built-in electromagnet 4 and a friction plate 5 is fixed to an end bracket 1, and an armature 10 facing the friction plate 5 with a gap g is linked to a rotating shaft 2. A boss 6 having a flange portion 6a is attached to the shaft 2, and a support disk 7 having approximately the same diameter as the flange portion 6a is attached to the stator 3 side of the boss 6.
The flange portion 6a and the support disk 7 are connected by bolts 11b.
is attached so as to be movable in the axial direction via ring-shaped leaf springs S1 alternately fixed to both members, and each opposing outer edge of the flange portion 6a and the support disk 7 is tapered to form a substantially V-shaped circle. A circumferential groove 8 is formed, an endless coil spring 9 is stuck in the circumferential groove 8, and a transparent support plate 7 has a large-diameter stepped portion 12a on the flange portion 6a side. Hole 1
2, and on the side of the stator 3 of the support disk 7, a ring-shaped leaf spring S2 with a spring force greater than that of the leaf spring S1 is provided.
The through hole 12 has a head portion 13 having a larger diameter than the through hole 12.
The stud bolt 11a is inserted from the flange portion 6a side and the pole N1b is attached from the stator 3 side.
By interposing the ring-shaped leaf spring S2, which is alternately fixed to both the armature 10 and the support disk 70,
The armature 10 is mounted so as to be movable in the axial direction, and a gap g2 is created between the large-diameter stepped portion 12a and the head 13.
The gap adjusting device for an electromagnetic brake is configured such that the dimension of is equal to the dimension of the gap g1 between the friction plate 5 and the armature 10.