JP3929884B2 - Non-excitation electromagnetic brake - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a non-exciting operation type electromagnetic brake capable of quickly releasing the contact between a rotary plate and a pressure-receiving plate when releasing a brake. <P>SOLUTION: The non-exciting operation type electromagnetic brake comprises an armature 30 being opposite to a field core and capable of only moving to an axial direction, the rotary plate 60 arranged to be opposite to the armature and loosely and movably fitting on an outer periphery of a center hub 50 inserted by a rotary shaft 40 in an axial direction, the pressure-receiving plate 70 arranged to be opposite to the rotary plate, a braking spring 80 urging the armature to a press contact direction so as to bring into press contact with the rotary plate, and an elastically connecting means elastically connecting between the center hub and the rotary plate. The elastically connecting means provides a contact portion elastically connected with an inner peripheral surface of the rotary plate at two places of a pressure-receiving plate side and an armature side, which hold a perpendicular surface at a center position to an axial direction. Further, the elastically connecting means is also set so that an axial component of elastically connecting force at the contact portion of the pressure-receiving plate side in a non-exciting state is greater than that at the contact portion of the armature side. <P>COPYRIGHT: (C)2004,JPO&amp;NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a non-excitation operation type electromagnetic brake.
[0002]
[Prior art]
FIG. 8 shows a conventional non-excitation actuated electromagnetic brake, FIG. 8 (a) is a plan view, and FIG. 8 (b) is a cross-sectional view taken along line A-O-B in FIG. 8 (a). It is. The non-excitation operation type electromagnetic brake shown in FIG. 8 includes a field core 120 in which the electromagnetic coil 110 is embedded, and the field core 120 when the electromagnetic coil 110 is not energized, that is, when the field core 120 is in a non-excitation state. The armature 130 that faces the gap G and is movable only in the axial direction, and the center hub 150 that is arranged to face the armature 130 and is fitted to the rotary shaft 140 rotates to move in the axial direction. A possible rotating plate 160, a pressure receiving plate 170 disposed to face the rotating plate 160, and a brake spring 180 that urges the armature 130 in a direction in pressure contact with the rotating plate 160 are provided. Although not shown, the rotating shaft 140 is pivoted on the field core 120 by a bearing such as a ball bearing.
[0003]
The rotating plate 160 is structured to be movable in the axial direction along the outer peripheral surface of a square center hub 150 with a corner cut as shown in FIG. A slight clearance (gap) exists between the inner peripheral surface of the inner diameter portion and the outer peripheral surface of the center hub 150. Therefore, as shown in FIG. 9, the leaf spring 154 is engaged with the axially extending grooves 152 provided at two locations on the outer peripheral surface of the center hub 150, and the curved portion is engaged with the center hub 150. By projecting from the outer peripheral surface, the leaf spring 154 is brought into elastic contact with the inner peripheral surface of the inner diameter portion of the rotating plate 160 as shown in FIG. As a result, the play due to the clearance between the center hub 150 and the rotating plate 160 is removed.
[0004]
In the non-excitation operation type electromagnetic brake having such a structure, the armature 130 is rotated by the brake plate 180 when the current is not flowing through the electromagnetic coil 110, that is, when the field core 120 is in the non-excitation state. The rotating plate 160 is sandwiched between the pressure receiving plate 170 and the armature 130, and the rotation is stopped, whereby the rotating shaft 140 is braked.
[0005]
On the other hand, when a current is passed through the electromagnetic coil 110, that is, when the field core 120 is in an excited state, the armature 130 is attracted to the field core 120, and the pressure contact between the armature 130 and the rotary plate 160 is released. Then, the rotating plate 160 is released from the clamping of the pressure receiving plate 170 and the armature 130 and becomes rotatable. Thereby, the brake of the rotating shaft 140 is released (for example, refer to Patent Document 1).
[0006]
[Patent Document 1]
Japanese Utility Model Publication No. 60-107638 [0007]
[Problems to be solved by the invention]
However, in the conventional non-excitation operation type electromagnetic brake as shown in FIG. 8, the leaf spring 154 is elastically in contact with the inner peripheral surface of the inner diameter portion of the rotating plate 160, and therefore, between the rotating plate 160 and the center hub 150. A frictional force that hinders the rotation of the rotating plate 160 in the axial direction works. Therefore, although the field core 120 is in an excited state and the rotating plate 160 is released from the clamping of the pressure receiving plate 170 and the armature 130, the rotating plate 160 rotates while being in contact with the pressure receiving plate 170, and the brake is released. Sometimes an excessive load was applied to the rotating shaft, and an overload was applied to the motor, causing abnormal heat generation. Furthermore, the friction between the rotating plate 160 and the pressure receiving plate 170 causes an unpleasant rubbing sound or wears the rotating plate 160 and shortens the life of the brake body.
[0008]
Therefore, an object of the present invention is to provide a non-excited operation type electromagnetic that has a long brake life and prevents contact between the rotating plate and the pressure receiving plate quickly and reliably when the brake is released, thereby preventing abnormal noise and heat generation. To provide a brake.
[0009]
[Means for Solving the Problems]
The invention according to claim 1 is a field core in which an electromagnetic coil is embedded, and an armature that is opposed to the field core with a gap between the field core and is movable only in the axial direction when the field core is in a non-excited state, A rotary plate that is disposed so as to face the armature and is fitted on the rotary shaft, and is loosely fitted on the outer periphery of the center hub so as to be movable in the axial direction, a pressure receiving plate arranged so as to face the rotary plate, and the armature Is installed between the outer peripheral surface of the center hub and the inner peripheral surface of the rotary plate to elastically contact the center hub and the rotary plate. In the non-excitation actuating electromagnetic brake having the elastic contact means for preventing rattling, the elastic contact means has a plane symmetric shape with the vertical plane at the center position in the axial direction as the central plane, and sandwiches the vertical plane. The rotation A contact portion that elastically contacts the pressure receiving plate side and the armature side at the edge portion of the inner peripheral surface of the rotating plate, and the axial center position of the elastic contact means in the non-excited state The said subject is achieved by decentering from the axial center position to the said armature side.
[0010]
According to a second aspect of the present invention, there is provided an armature capable of moving only in the axial direction while facing a gap between a field core having an electromagnetic coil embedded therein and the field core when the field core is in an unexcited state. A rotating plate that is arranged so as to be movable in the axial direction on the outer periphery of a center hub that is arranged to face the armature and is fitted to the rotating shaft, and a pressure receiving plate that is arranged to face the rotating plate, A brake spring that urges the armature in a direction in which the armature is pressed against the rotating plate, and is mounted between an outer peripheral surface of the center hub and an inner peripheral surface of the rotating plate to elastically contact the center hub and the rotating plate. In the non-excitation actuating electromagnetic brake having elastic contact means for preventing rattling between the two, the elastic contact means has an asymmetric shape composed of two curved portions with a vertical plane at the axial center position as a central plane. , A contact portion that elastically contacts the pressure receiving plate side and the armature side at the edge portion of the inner peripheral surface of the rotating plate with the vertical surface interposed therebetween, and in a non-excited state, the curved portion is The pressure-receiving plate side is curved more greatly than the armature side, thereby achieving the above-mentioned problem.
[0011]
Furthermore, the invention according to claim 3 achieves the above-mentioned object in addition to the configuration of the invention according to claim 1 or claim 2, wherein the elastic contact means is a double leaf spring.
[0012]
[Action]
In the non-excitation actuating electromagnetic brake according to claim 1, the elastic means has a plane-symmetrical shape with the vertical plane at the axial center position as the central plane, and the edge portion of the inner peripheral surface of the rotating plate sandwiching the vertical plane The contact portion that makes elastic contact at two locations on the pressure receiving plate side and the armature side, and the axial center position of the elastic contact means is decentered from the axial center position of the rotary plate to the armature side in the non-excited state. Therefore, the rotating plate moves to the armature side due to the difference in elastic contact force that acts on the two contact parts between the elastic contact means and the rotating plate when excited, and the rotating plate and the pressure receiving plate are in contact with each other. Is released promptly and reliably.
[0013]
In the non-excitation actuating electromagnetic brake according to claim 2, the elastic contact means has an asymmetric shape composed of two curved portions with the vertical plane at the axial center position as the central plane, and the rotary plate sandwiches the vertical plane. The edge part of the inner peripheral surface constitutes a contact portion that elastically contacts at two places on the pressure receiving plate side and the armature side, and in the non-excited state, the bending portion bends more on the pressure receiving plate side than on the armature side. As a result, the rotating plate moves to the armature side due to the difference in elastic contact force acting on the two contact portions of the elastic contact means and the rotating plate when excited, and the rotating plate and the pressure receiving plate Contact is quickly and reliably released.
[0014]
In the non-excitation actuating electromagnetic brake according to claim 3, since the elastic contact means is a double spring, the action of the non-excitation actuating electromagnetic brake according to claim 1 or 2 is ensured with a simple configuration. Played.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described based on Example 1 with reference to the drawings. FIG. 1 shows Example 1 which is an example of an embodiment of the non-excitation operation type electromagnetic brake of the present invention. FIG. 1 (a) is a plan view, and FIG. 1 (b) is FIG. It is sectional drawing in the AOB line of a). The non-excitation operation type electromagnetic brake shown in FIG. 1 is opposed to the field core 20 in which the electromagnetic coil 10 is embedded, and the field core 20 via the gap G when the field core 20 is in the non-excitation state. The armature 30 that can move only in the direction of the armature 30 and the center hub 50 that is disposed opposite to the armature 30 and that is fitted to the rotating shaft 40, rotate in the axial direction, and face the rotating plate 60. And a brake spring 80 that urges the armature 30 in a direction in which the armature 30 is pressed against the rotating plate 60.
[0016]
The pressure receiving plate 70 is formed with a circular center hole 70a at the center thereof, and three through holes and three through bolts 92 (FIG. 1 (b) through which the tip portions 90a of the three bolts 90 pass. ) Are formed at equal intervals in the circumferential direction. The gap adjusting nut 90b is fastened to the tip portions 90a of the three bolts 90, so that the gap between the pressure receiving plate 70 and the field core 20 is kept constant by the spacer 96 and the presser spring 94. Further, an O-ring 34 serving as a cushioning material is held between the end faces of the field core 20 and the armature 30 that are opposed to each other, with a gap provided on the outer periphery of each guide pin 32 that guides the movement of the armature 30 in the axial direction. The O-ring 34 has a function of reducing a collision sound when the armature 30 is attracted to the field core 20 when the field core 20 is excited.
[0017]
A square center hole is formed at the center of the rotating plate 60, and a square center hub 50 with a cross-sectional shape having a corner is loosely fitted in the center hole. Since the rotary plate 60 is structured to be movable in the axial direction along the outer peripheral surface of the center hub 50, the rotary plate 60 is located between the inner peripheral surface of the inner diameter portion of the rotary plate 60 and the outer peripheral surface of the center hub 50. There is a slight clearance (gap). Therefore, as shown in FIG. 2, elastic contacting means are provided in the axially extending grooves 52 provided at two locations on the outer peripheral surface of the center hub 50. This elastic contact means includes a leaf spring 54 in which a vertical surface at the center position in the longitudinal direction, that is, an axial direction, has a central surface as a concave portion, and two curved portions 54a and 54b are formed at plane-symmetrical positions. And is locked to the groove 52 by locking portions 54c and 54d formed at both ends. Then, by projecting the two curved portions 54a and 54b from the outer peripheral surface of the center hub 50, the curved portions 54a and 54b of the leaf spring 54 are rotated as shown in C portion of FIGS. 3 and 1B. The plate 60 is elastically contacted at two locations on the inner peripheral surface of the inner diameter portion.
[0018]
FIG. 4 is an enlarged view of a portion C in FIG. As shown in this figure, in the non-excited state, the axial center position P1 of the leaf spring 54 is eccentric from the axial center position P2 of the rotating plate 60 toward the armature 30 side. Therefore, in the non-excited state, the axial force of the elastic contact force acting on the two contact portions of the rotating plate 60 and the leaf spring 54 is directed toward the pressure receiving plate 70 as shown by the arrows in the figure. The force FR in the direction of the armature 30 is larger than the force FL. As a result, the FL and FR are moved in the direction of the armature 30 so that FL and FR become equal when excited, that is, the plate spring 54 and the axial center position are aligned, and the rotary plate 60 and pressure receiving plate 70 are moved. Contact with is quickly and reliably released.
[0019]
In the first embodiment described above, a plate spring in which the vertical surface at the axial center position is the central surface, the central portion is the concave portion, and two curved portions are formed at the plane-symmetrical positions is used as the elastic contact means. Is a shape that constitutes a contact portion that elastically contacts the inner peripheral surface of the rotating plate at two locations on the pressure receiving plate side and the armature side with respect to the central surface, and the elastic contact force at the contact portion on the pressure receiving plate side in the non-excited state. The axial direction component is not limited to this as long as it can be larger than the axial direction component of the elastic contact force at the contact portion on the armature side.
[0020]
For example, as shown in FIG. 5, instead of a leaf spring, a flat plate 56 having two ridges sandwiching the center surface and a coil spring 58 that urges the flat plate 56 outward from the center hub 50 side. It is also possible. Moreover, as shown in FIG. 6, it is possible to use two single leaf springs 54 instead of the two leaf springs.
[0021]
Next, another embodiment of the present invention will be described with reference to FIG. Since the configuration other than the elastic contact means is the same as that of the first embodiment, detailed description thereof is omitted. FIG. 7 is an enlarged sectional view of the vicinity of the elastic contact means in the second embodiment. As shown in FIG. 7, a leaf spring 54 in which two curved portions 54a and 54b having a non-axisymmetric shape are formed by setting a vertical portion P in the longitudinal direction, that is, an axial center position as a central plane, a central portion as a concave portion. And is locked in the groove of the center hub 50 by locking portions 54c and 54d formed at both ends. Then, by projecting the two curved portions 54 a and 54 b from the outer peripheral surface of the center hub 50, the two curved portions 54 a and 54 b are elastically contacted at two locations at the edge portion of the inner peripheral surface of the inner diameter portion of the rotating plate 60.
[0022]
As shown in this figure, the two curved portions of the leaf spring 54 are curved more largely on the pressure receiving plate 70 side than on the armature 30 side. Therefore, in the non-excited state, the axial force of the elastic contact force acting on the two contact portions of the rotating plate 60 and the leaf spring 54 is directed toward the pressure receiving plate 70 as shown by the arrows in the figure. The force FR in the direction of the armature 30 is larger than the force FL. As a result, the rotating plate 60 moves in the direction of the armature 30 due to the difference between the elastic contact force FL and the elastic contact force FR in the excited state, and the contact between the rotary plate 60 and the pressure receiving plate 70 is quickly and reliably released. The
[0023]
【The invention's effect】
In the non-excitation actuating electromagnetic brake according to claim 1, the elastic means has a plane-symmetrical shape with the vertical plane at the axial center position as the central plane, and the edge portion of the inner peripheral surface of the rotating plate sandwiching the vertical plane The contact portion that makes elastic contact at two locations on the pressure receiving plate side and the armature side, and the axial center position of the elastic contact means is decentered from the axial center position of the rotary plate to the armature side in the non-excited state. Therefore, the rotating plate moves to the armature side due to the difference in elastic contact force that acts on the two contact parts between the elastic contact means and the rotating plate when excited, and the rotating plate and the pressure receiving plate are in contact with each other. Is released promptly and reliably, and the occurrence of abnormal noise is also suppressed. Further, an excessive load on the motor due to the contact between the rotating plate and the pressure receiving plate is prevented. Further, the wear of the rotating plate is suppressed and the life of the device is extended. Moreover, since it is not necessary to care about the direction when attaching the elastic means, the assembly process is simplified.
[0024]
In the non-excitation actuating electromagnetic brake according to claim 2, the elastic contact means has an asymmetric shape composed of two curved portions with the vertical plane at the axial center position as the central plane, and the rotary plate sandwiches the vertical plane. The edge part of the inner peripheral surface constitutes a contact portion that elastically contacts at two places on the pressure receiving plate side and the armature side, and in the non-excited state, the bending portion bends more on the pressure receiving plate side than on the armature side. As a result, the rotating plate moves to the armature side due to the difference in elastic contact force acting on the two contact portions of the elastic contact means and the rotating plate when excited, and the rotating plate and the pressure receiving plate Contact is quickly and reliably released, and abnormal noise is also suppressed. Further, an excessive load on the motor due to the contact between the rotating plate and the pressure receiving plate is prevented. Further, the wear of the rotating plate is suppressed and the life of the device is extended.
[0025]
In addition to the effect exhibited by the non-excitation actuating electromagnetic brake according to claim 1 or 2, the non-exciting actuating electromagnetic brake according to claim 3 is characterized in that the elastic means is a double leaf spring. The configuration can be simplified.
[Brief description of the drawings]
FIG. 1 is a diagram showing a non-excitation operation type electromagnetic brake according to an embodiment of the present invention, wherein (a) is a plan view thereof and (b) is an A-O-B line of (a). It is sectional drawing in a line.
FIG. 2 is an enlarged perspective view of a center hub and elastic contact means of the non-excitation operation type electromagnetic brake of FIG. 1;
3 is an enlarged perspective view showing a state in which the center hub and elastic contact means shown in FIG. 2 are loosely fitted to a rotating plate. FIG.
FIG. 4 is an enlarged view of a portion C in FIG.
FIG. 5 is a diagram showing another form of the elastic contact means.
FIG. 6 is a view showing another form of the elastic contact means.
FIG. 7 is a diagram showing elastic contact means used in a non-excitation actuating electromagnetic brake according to another embodiment of the present invention.
8A and 8B are diagrams showing a conventional non-excitation operation type electromagnetic brake, wherein FIG. 8A is a plan view thereof, and FIG. 8B is a cross-sectional view taken along line A-O-B in FIG.
FIG. 9 is an enlarged perspective view of a center hub and elastic contact means of a conventional non-excitation operation type electromagnetic brake.
10 is an enlarged perspective view showing a state in which the center hub and the elastic contact means shown in FIG. 9 are loosely fitted to a rotating plate.
[Explanation of symbols]
10, 110 ... Electromagnetic coils 20, 120 ... Field cores 30, 130 ... Armature 32 ... Guide pins 34 ... O-rings 40, 140 ... Rotating shafts 50, 150 ... Center Hubs 52, 152 ... grooves 54, 154 ... leaf springs 60, 160 ... rotating plates 70, 170 ... pressure receiving plates 80, 180 ... braking springs 90 ... bolts

Claims (3)

A field core in which an electromagnetic coil is embedded, an armature that is opposed to the field core via a gap when the field core is in a non-excited state, and is movable only in the axial direction, and is disposed to face the armature A rotating plate loosely fitted to the outer periphery of the center hub fitted to the rotating shaft so as to be movable in the axial direction, a pressure receiving plate arranged to face the rotating plate, and a direction in which the armature is pressed against the rotating plate A brake spring that is urged against the elastic member, and an elastic contact that is mounted between the outer peripheral surface of the center hub and the inner peripheral surface of the rotating plate to elastically contact the center hub and the rotating plate to prevent rattling of both. In a non-excitation actuating electromagnetic brake having means,
The elastic contact means has a plane-symmetrical shape with a vertical plane at the axial center position as a central plane, and the pressure receiving plate side and the armature side at the edge portion of the inner peripheral surface of the rotary plate with the vertical plane in between. The contact portion is configured to be elastically contacted at two locations, and in the non-excited state, the axial center position of the elastic contact means is eccentric from the axial center position of the rotating plate toward the armature. Non-excitation actuated electromagnetic brake. A field core in which an electromagnetic coil is embedded, an armature that is opposed to the field core via a gap when the field core is in a non-excited state, and is movable only in the axial direction, and is disposed to face the armature A rotating plate loosely fitted to the outer periphery of the center hub fitted to the rotating shaft so as to be movable in the axial direction, a pressure receiving plate arranged to face the rotating plate, and a direction in which the armature is pressed against the rotating plate A brake spring that is urged against the elastic member, and an elastic contact that is mounted between the outer peripheral surface of the center hub and the inner peripheral surface of the rotating plate to elastically contact the center hub and the rotating plate to prevent rattling of both. In a non-excitation actuating electromagnetic brake having means,
The elastic contact means has an asymmetrical shape composed of two curved portions with a vertical plane at the axial center position as a central plane, and the pressure receiving plate side at the edge portion of the inner peripheral surface of the rotating plate with the vertical plane interposed therebetween And a contact portion that elastically contacts at two locations on the armature side, and in the non-excited state, the curved portion is curved more greatly on the pressure receiving plate side than on the armature side. Excitation actuated electromagnetic brake.   The non-excitation actuating electromagnetic brake according to claim 1 or 2, wherein the elastic contact means is a two-plate spring.

Images