JPH0138351Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a non-excited electromagnetic brake that applies braking to a braked object by the force of a spring and releases the braking by electromagnetic attractive force. The purpose of this is to eliminate any backlash that occurs between the plates and the support rods that support them.

First, a conventional electromagnetic brake will be explained with reference to FIG. In the figure, 1 is a yoke, 2 is a coil housed in a recess of the yoke 1, and 3 is an armature support rod embedded horizontally in the yoke 1 with one side facing the magnetic pole surface, which is the inner surface of the yoke 1. 4 for axial movement. 5 is support rod 4
A pressing plate 6 supported by a nut screwed onto the end of the support rod 4 serves to prevent the pressing plate from moving in the axial direction and to adjust the gap g between the armature 3 and the yoke 1. A brake disk 7 is located between the armature 3 and the pressing plate 5, and is engaged with a spline 8a of the braked shaft 8 at a spline 7a provided on the inner circumference. Most of the 9 is inserted into each of a plurality of holes provided on the circumference of the yoke 1, and the armature 3 is pressed in the direction of the pressing plate 5 by a braking spring supported by the hole. are doing.

The conventional electromagnetic brake consists of the above coil 2.
When no current is supplied to the armature 3, the force of the spring 9 presses the brake disc 7 against the pressing plate 5 via the armature 3, and as a result, the brake disc 7 is clamped between the armature 3 and the pressing plate 5. By fixing the yoke 1 in a suitable position on the machine using the electromagnetic brake, the braked shaft 8 is braked, and when current is supplied to the coil 2, an electromagnetic attractive force is generated against the armature 3, This armature is attracted toward the yoke 1 against the force of the spring 9, the clamping pressure on the brake disc 7 is removed, and the braking on the braked shaft 8 is released.

However, in the case of such conventional electromagnetic brakes,
The armature 3 and the pressure plate 5 are supported by a support rod 4, and the armature moves axially on the support rod 4 for braking and releasing the brake, and the pressure plate 5 moves axially on the support rod 4 for adjusting the gap g. It is necessary to have a structure that allows sliding, and for this purpose, the armature 3 and the press plate 5 are fitted to the support rod 4 with a fitting tolerance maintained. Therefore, there is a backlash between both the armature 3 and the pressing plate 5 and the support rod 4, which causes a delay in the braking operation, reducing the stopping accuracy of the braked part, or causing the braking to be released. When the brake disc 7 is rotated, these armatures and the pressing plate 5 can move freely in the rotational direction within the range of the above-mentioned rotation with respect to the support rod 4, so that these armatures and the pressing plate are supported. The disadvantage is that it collides with the rod and generates noise.

The present invention eliminates such drawbacks, and an embodiment of the present invention will be described below with reference to FIGS. 2 and 3. First, in FIG. 2, 11 is a yoke, 12 is a coil, 13 is an armature that faces the magnetic pole part connected to the yoke 1 with an air gap, and 14 is a yoke 11.
A plurality of support bolts are provided horizontally on the circumference of the yoke and passed through the yoke, and the screw portions at the tips of the support bolts are screwed into screw holes in the press plate 15 to connect the press plate and the yoke 11. 16 is a lock nut screwed onto the threaded portion of the support bolt 14; 17 is a braked shaft 18 between the armature 13 and the pressing plate 15;
19 is a braking spring fitted into the support bolt 14, and 20 is an annular support plate fitted into the support bolt 14 between the armature 13 and the pressing plate 15. A considerable gap is provided at the fitting part with the support bolt 14 to prevent contact with the bolt, and a threaded hole 21 is formed in the peripheral edge, and this threaded hole part is used to connect the equipment used for the brake (see Fig. (not shown) and is fixed in place so that it does not rotate during operation. 22 and 23 are annular leaf springs; one leaf spring 22 is located between the armature 13 and the support plate 20 and connects the two;
is located between the press plate 15 and the support plate 20 and connects them, and the armature 13 and the press plate 15 are supported on the support plate 20 by these leaf springs. The dimensions of the leaf springs 22 and 23 are set so that the distance between the armature 13 and the pressing plate 15 in the brake release state is slightly larger than the thickness of the braking surface of the brake disc 17. In the embodiment, the leaf springs 22 and 23 are annular ones, but a plurality of arcuate or strip-shaped leaf springs may be arranged on the circumference.

The first embodiment of the present invention is constructed as described above, and when no current is supplied to the coil 12, the armature 13 is moved against the pressing plate 1 by the repulsive force of the spring 19.
Since the yoke 11 is configured to be able to move freely in the axial direction (left and right directions in the drawing), the brake disc 17 is pushed toward the 5 side.
is clamped between the armature 13 and the pressing plate 15, and its brake disc 17, therefore this disc 1
Braking is applied to a braked shaft 18 that is dynamically connected to the coil 12, and when a current is supplied to the coil 12, the armature 13 is attracted to the yoke 11 side against the force of the spring 19 by electromagnetic attraction force. As a result, the clamping pressure on the brake disc 17 by the armature 13 and the pressing plate 15 is removed, and the braking force on the braked shaft 18 is released.

To adjust the gap between the armature 13 and the magnetic pole part of the yoke 11, loosen the lock nut 16 and rotate the support bolt 14 using a spanner or the like, and the press plate 15 will be attached to the screw of the bolt. moves, and the gap changes.

The original operation of the brake described above is essentially the same as that of the conventional brake shown in FIG. Since this support plate is fixed to the equipment used, the braking torque during braking is generated by both leaf springs 22, 2.
3. FIG. 3 shows another embodiment of the present invention, in which a coil spring 24 is fitted around the support bolt 14 between the armature 13 and the pressing plate 15, and the armature 13 is pressed by the repulsive force of this coil spring. The coil spring is designed to press open the plate 15, and the action of this coil spring ensures that the brake can be released more reliably when power is supplied to the coil 12.

In this case, as described above, the brake disc 17 and the push plate 15 are connected to the support plate 2 through the leaf springs 22 and 23, respectively.
By supporting this support plate on a fixed part so that it does not rotate, the braking torque is received by the plate springs 22 and 23. Therefore, at least the armature 1 that needs to be moved in the axial direction
3, and a support plate 20 that supports this amateur
There is no torque transmission relationship between the support bolt 14 and the support bolt 14, so it is sufficient to increase the gap between them to avoid mutual contact, and to connect the pressing plate 15 integrally with the bolt 14. 13 and the pressing plate 15 do not need to have a backlash in the rotational direction with respect to the support bolt 14, and can improve the stopping accuracy of the braked object during braking. There is no problem such as noise generation due to the collision of the pressing plate 15 with the bolt 14, and furthermore, since the armature and the pressing plate are reliably opened by the leaf spring when the brake is released, it is possible to eliminate the idling torque. It's also effective.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing a conventional electromagnetic brake, Fig. 2 is a sectional view of the upper half of the electromagnetic brake showing one embodiment of the invention, and Fig. 3 is a partial sectional view showing another embodiment of the invention. be. 11...York, 13...Amachiyua, 14...
... Support bolt, 15 ... Pressing plate, 17 ... Brake disk, 20 ... Support plate, 22, 23 ... Leaf spring.

Claims (1)

[Scope of utility model registration request] A armature facing the magnetic pole portion of the yoke, a pressing plate facing the armature with a brake disk in between, a support bolt passing through the armature in the axial direction and connecting the pressing plate and the yoke; A support plate is provided between the armature and the pressing plate and has the bolt passed through it, and a leaf spring is provided on the support plate to connect and support the armature and the pressing plate, and the leaf spring receives the braking torque during braking. An electromagnetic brake characterized by: