JP2669944B2 - Non-excitation actuated electromagnetic brake silencer - Google Patents

Abstract

PURPOSE:To effectively reduce collision sound at the time of operating by burying an elastic body equipped with a projecting part projecting from the end surface in recessed parts partially provided in one end surface where a fixed iron core and a movable iron core are opposed to each other. CONSTITUTION:Recessed parts 12 such as ring channels and the like are provided in the inner and outer peripheries of the electromagnetic coil 2 of a fixed iron core 1, and elastic bodies 11 such as O-rings and the like are buried. Since the depth of each recessed part 12 is a little shallower than the thickness of the elastic body 11, the projecting part of the elastic body 11 is projected from the end surface of the fixed iron core 1. As the projecting parts of the elastic bodies 11 are partial by this construction, projecting dimension is contracted by pushing pressure of a movable iron core 4. Therefore, the movable iron core 4 is electrically, stuck more closely to the fixed iron core 1 to suppress increase of magnetic resistance, completely stuck to the same on account of design, and completely exhibits magnetic force. Moreover mechanically, contraction of the projecting part requires a collision time for distortion by that quantity, collision is slowly damped, and collision sound is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a silencer for operating noise of a non-excitation actuated electromagnetic brake for braking / holding a rotating body.

[0002]

2. Description of the Related Art Conventionally, as an operating noise of a non-excitation actuated electromagnetic brake, there are a sound that a movable iron core by a braking spring collides with a rotating disk during braking and a sound that a movable iron core collides with a fixed iron core during attraction. In the former case, the collision sound is relatively small because the material of the rotating disk is resin, but in the latter case, a large collision sound is generated because the mutual materials are metal such as magnetic material. Therefore, as a method of reducing the collision noise of the fixed iron core and the movable iron core, which is the operation noise of the electromagnetic brake, there are the following three methods.
(1) The brake part is wrapped with a soundproof cover (for example, Japanese Patent Application No. 2-107186). (2) The attraction force of the electromagnetic coil is reduced to reduce the collision noise between the iron cores. (3) A buffer plate having viscoelasticity is arranged on the end surface portion of the fixed iron core (for example, Japanese Utility Model Laid-Open No. 2-27033).

[0003]

In order to meet the demand for noise reduction in the operating environment and reduce the operating noise of the electromagnetic brake which is frequently generated, the above-mentioned method is available, but it has the following problems. The problem (1) is that the soundproof cover raises the cost and the heat generated in the brake is not well dissipated. In the case of (2), in order to produce the same braking torque, it is necessary to increase the external dimensions, which is problematic in terms of size and economy. (3) is
Since the magnetic resistance increases and the electromagnetic force decreases, the braking force decreases, and the operating noise does not decrease so much.

Therefore, an object of the present invention is to provide a silencer for a non-excitation actuated electromagnetic brake capable of effectively reducing the collision noise during the operation of the fixed iron core and the movable iron core without reducing the braking force. is there.

[0005]

A silencer for a non-excitation actuated electromagnetic brake according to a first aspect of the present invention is a fixed iron core around which an electromagnetic coil is wound, and the fixed iron core is sucked to release braking and is pressed by a braking spring. A movable iron core that can be moved in the axial direction to brake by
In a non-excitation actuated electromagnetic brake consisting of a rotating disc positioned between the movable iron core and the braking plate and being braked or released, the fixed iron core and the movable iron core are opposed to each other. A concave portion having a U-shaped cross section, which is an annular groove, is provided on one side, and an annular elastic body having a circular cross section is embedded in the concave portion, the projecting portion projecting from the end surface.

A silencer for a non-excitation actuated electromagnetic brake according to a second aspect of the present invention is the silencer according to the first aspect, wherein a plurality of the recesses are arranged on the end surface.

[0007]

In the invention 1, since the protruding portion 11a of the elastic body 11 is partial, the protruding portion 11a is pressed by the movable iron core 4 and the protruding dimension is contracted. Therefore, the movable iron core 4 is electrically connected to the fixed iron core 1. , Closer contact and increase in magnetic resistance are suppressed, and depending on the design, complete close contact and electromagnetic force are fully exerted. In addition, mechanically contracting the protrusion 11a requires a collision time (although it is minute) to distort that much, and the collision is gradually buffered within the time, and the collision noise is reduced. Since the method (3) of the conventional example is a plate, the strain is extremely small and almost close to the volume strain, so that the silencing action of the present invention is larger. In addition, since the annular elastic body having a circular cross section is embedded in the U-shaped concave portion formed of the annular groove, the elastic body is elastic between the groove wall and the peripheral surface of the elastic body at each corner of the concave portion. A void is formed to allow deformation, and the elastic body is unlikely to crack even when subjected to repeated pressing force over a long period of time. Further, the annular groove is easy to work, and if the annular elastic body embedded in the groove is made slightly smaller in diameter, it is elastically held in the annular groove by itself. Further, a commercially available O-ring can be used as the annular elastic body, and it is not necessary to specially manufacture and prepare the elastic body. According to the second aspect of the invention, a more stable silencing effect is obtained by the plurality of annular elastic bodies.

[0008]

1 is a partial cross-sectional view of the embodiment, and FIG. 2 is an enlarged cross-sectional view near the elastic body of FIG. In the figure, first, to explain the same parts as in the prior art, the fixed iron core 1 is fixed to the studs 5 mounted on the braking plate 7 by the nuts 10,
A movable iron core 4 is disposed so as to face the fixed iron core and be movable in the axial direction by the guide of the stud 5. An electromagnetic coil 2 is wound around the fixed iron core 1. The movable iron core 4 and the rotating disk 6 are pressed against the braking plate 7 by the pressing force of a plurality of braking springs 3 embedded in the fixed iron core 1, and the rotating disk 6 and the center hub 8 mounted on the rotating shaft 9 and the shaft. It is fitted so that it can move in any direction.

When a voltage is applied to the electromagnetic coil 2 in this state, the movable iron core 4 is attracted by the electromagnetic attraction force, and the braking spring 3
The rotating disc 6 pressed against the braking plate 7 by the pressing force becomes free to rotate and is rotated by the rotating force of the rotating shaft 9. When the voltage applied to the electromagnetic coil 2 disappears, the electromagnetic attraction force disappears, and the movable iron core 4 is pressed against the rotating disk 6 and the braking plate 7 by the pressing force of the braking spring 3, so that the rotating disk 6 and the rotating shaft. 9 stops. With such a structure, when a voltage is applied to the electromagnetic coil 2 described above, the movable iron core 4 is attracted to the fixed iron core 1 and collides with each other to generate a loud collision noise.

Therefore, as a characteristic structure of the embodiment, a concave portion 12 having a U-shaped cross section, which is an annular groove, is provided on the inner and outer circumferences of the electromagnetic coil 2 of the fixed iron core 1, and the O-ring or the like is provided in each of these two grooves. An annular elastic body 11 having a circular cross section is embedded. The depth of the recess 12 is made slightly shallower than the cross-sectional diameter of the elastic body 11 so that the protruding portion 11a of the elastic body 11 protrudes from the end surface of the fixed iron core 1.

According to such a structure, since the protruding portion 11a of the elastic body 11 is partial, the protruding portion 11a is pressed by the movable iron core 4 and the protruding size is reduced. The fixed core 1 is more closely adhered to the magnetic core 1 to suppress an increase in magnetic resistance, and depending on the design, the fixed iron core 1 is completely adhered and electromagnetic force is fully exerted. Moreover, mechanically contracting the protrusion 11a requires a collision time (although it is minute) to distort that much, and the collision is gradually buffered within the time, and the collision noise is reduced. Since the method (3) of the conventional example is a plate, the strain is extremely small and almost close to the volume strain, so that the silencing action of the present invention is larger. Since the elastic body has a smaller cross section toward the tip, the cushioning action is weak at first, and gradually becomes stronger, and the silencing action is large. Also, the recess 1
At each corner of No. 2, a gap is formed between the groove wall and the peripheral surface of the elastic body 11 to allow the elastic body to elastically deform, and the elastic body 11 is unlikely to crack even if repeatedly subjected to pressing force for a long period of time. . The recess 11 may be provided on the movable iron core side.

[0012]

The silencer for a non-excitation actuated electromagnetic brake according to the present invention includes a fixed iron core around which an electromagnetic coil is wound, a shaft which is sucked by the fixed iron core to release braking, and which is pushed by a braking spring to brake. In a non-excitation actuated electromagnetic brake comprising a movable iron core movable in a direction and a rotating disc positioned between the movable iron core and a braking plate for braking or releasing the braking, the fixed iron core and the movable core are provided. A concave portion having a U-shaped cross section, which is an annular groove, is provided on either one of the end surfaces facing the iron core. To do. According to such a configuration, the partial protruding portion is easily pushed by the movable iron core and is easily distorted in the axial direction, and the kinetic energy of the movable iron core is well converted into the strain energy. That is, there is an effect of muting the collision sound. In addition, the elastic body is less likely to crack and has excellent durability. In addition, the annular groove has the effect that it is easy to machine and has the self-holding force of the elastic body. There is no need to make and prepare. Furthermore, the second aspect of the invention has an effect that a plurality of annular elastic bodies can contribute to a reduction in cost while securing a sufficient silencing action and durability, such as a more stable silencing action being obtained.

[Brief description of the drawings]

FIG. 1 is a partial sectional view of an embodiment.

FIG. 2 is an enlarged cross-sectional view of the vicinity of the elastic body of FIG.

[Explanation of symbols]

 1 Fixed Iron Core 2 Electromagnetic Coil 3 Braking Spring 4 Movable Iron Core 6 Rotating Disc 7 Braking Plate 11 Elastic Body 11a Projection 12 Recess

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-60-40835 (JP, A) Actual development 62-15630 (JP, U) Actual development 61-137132 (JP, U) Actual development 2- 27033 (JP, U) Actual opening Sho 58-140736 (JP, U) Actual opening Sho 54-161886 (JP, U)

Claims (2)

(57) [Claims] 1. A fixed iron core around which an electromagnetic coil is wound, a movable iron core which is attracted to the fixed iron core to release braking, and which is pushed by a braking spring to be movable in the axial direction, and the movable iron core and the braking. In a non-excitation actuated electromagnetic brake consisting of a rotating disc positioned between the plate and braked or released, a ring-shaped groove is provided on either one of the facing end faces of the fixed core and the movable core. A silencer for a non-excitation actuated electromagnetic brake, characterized in that a recess having a U-shaped cross section is provided, and an annular elastic body having a circular cross section, which is provided with a protrusion protruding from the end face, is embedded in the recess. 2. The silencer for a non-excitation actuated electromagnetic brake according to claim 1, wherein a plurality of the recesses are arranged on the end face.