JPH05282982A - Electromagnetic relay - Google Patents

Abstract

PURPOSE:To prevent the generation of noise due to the vibration which is produced with the collision of a core with an armature and the collision of an stationary contact with a movable contact and propagated through a case into air. CONSTITUTION:The outer surface of a case 6 is wholly coated with an impact absorbing material 20a to be fastened. Thereby, the vibration which is produced with the collision of a core 1 with an armature 5 and the collision of a stationary contact 9a, 9b with a movable contact 10 is prevented from being propagated through the case 6 into air.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic relay, and more particularly to an electromagnetic relay having an armature supported by a hinge spring, and an electromagnetic relay application device having the electromagnetic relay mounted on a circuit board.

FIG. 7 shows a perspective view of an electromagnetic relay of this kind in which a current is applied to a coil to form a magnetic field to open and close contacts. As shown in FIG. 7, one surface of the L-shaped yoke 4 is connected and fixed to the core 1 near the bottom of the coil 2 wound around the spool 3, and the other surface of the L-shaped yoke 4 is bent. An armature 5 is side-connected to the front end side of the surface via a hinge spring 7. The core 1 is inserted in the hollow cylindrical portion of the spool 3, and faces the armature 5. The hinge spring 7 connected to the armature 5 by the boss 11 has a movable spring 8 in the direction opposite to the hinge portion, and a movable contact 10 is arranged near the tip thereof. The movable contact 10 is surrounded vertically and fixed contacts 9a, 9
b is arranged. When a current is applied to the coil 2, the armature 5 is attracted to the core 1, so that the movable contact 10 and the fixed contacts 9a, 9b can be electrically connected / disconnected. The case 6 is fixed to the spool 3 and has terminals 12a, 12b, 1
2c is exposed outside the main body of the electromagnetic relay.

[0003]

In the conventional electromagnetic relay, the vibration generated by the collision between the armature and the core and the collision between the movable contact and the fixed contact propagates into the air through the case and is exposed to the outside of the main body of the electromagnetic relay. There is a problem that a large amount of noise is generated by propagating to the substrate through the terminal and propagating from the substrate into the air.

[0004]

The electromagnetic relay of the present invention comprises:
It is characterized in that it has a case to which at least one of the outer surface and the inner surface is applied and fixed with a shock absorbing material.

In the electromagnetic relay application apparatus of the present invention, the electromagnetic relay is mounted on a circuit board, or the electromagnetic relay or an electromagnetic relay outside the electromagnetic relay is mounted on a circuit board and then mounted on a case. A shock absorber is applied and fixed to at least the surface of the circuit board around the relay.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present technology will be described with reference to the drawings. FIG. 1 is a perspective view of an electromagnetic relay according to an embodiment of the present invention. As shown in FIG. 1, an impact absorbing material (Nippon Automation, trade name Gelnac (registered trademark), paint type) is applied to the entire outer surface of the ace with a spatula or the like to a substantially uniform thickness. At this time, it is sufficient that the amount of impact absorbing material applied is about 0.5 g and the average wall thickness is about 0.3 mm. After coating, it is dried at room temperature for about 30 minutes. The vibration generated from the collision between the armature and the core, the movable contact and the fixed contact during the operation and restoration of the electromagnetic relay is damped by the shock absorbing material applied and fixed to the outer surface of the case.
This has the effect of reducing the sound pressure level of the electromagnetic relay.
This is shown in FIG. FIG. 4 shows the relationship between the applied amount of the shock absorbing material and the measured sound pressure level. When the applied amount is about 0.5 g and the average wall thickness is 0.25 mm, the sound pressure level is about 10 dB (A) compared to the conventional case. descend. Note that FIG. 3 shows a method of measuring the sound pressure level.

Next, FIG. 2A is a perspective view of an electromagnetic relay application device of the present invention. As shown in FIG. 2 (a), mounting the electromagnetic relay of the present invention on a circuit board results in a reduction of 5 to 7 dB (A) compared to the conventional case. This is shown in FIG. FIG. 5 shows the relationship between the applied amount of the shock absorbing material and the measured sound pressure level when the circuit board is mounted.

Next, FIG. 2B is a perspective view of a second embodiment of the electromagnetic relay application apparatus of the present invention. As shown in FIG. 2B, after mounting the electromagnetic relay of the present invention on a circuit board, the case of the electromagnetic relay or the surface of the circuit board around the electromagnetic relay is applied and fixed with a shock absorbing material. At this time, a coating amount of the impact absorbing material of about 0.6 g is sufficient. In this case, the sound pressure level of the electromagnetic relay application device of the present invention is 9 to
It decreases by 13 dB (A). This is shown in FIG. FIG. 6 shows the relationship between the application area of the shock absorbing material on the surface of the circuit board and the measured sound pressure level.

[0009]

According to the present invention, since at least one of the outer surface and the inner surface of the case is applied and fixed by the shock absorbing material, the vibration generated by the collision between the core and the armature and the collision between the movable contact and the fixed contact is prevented. It has the effect of preventing it from propagating into the air through the case, and as a result no noise is generated. Further, the electromagnetic relay of the present invention is mounted on a circuit board, or after mounting, at least the surface of the circuit board around the case and the electromagnetic relay is coated and fixed with a shock absorbing material, so that the noise of the electromagnetic relay applied device is reduced. Have an effect.

[Brief description of drawings]

FIG. 1 is a perspective view of an electromagnetic relay according to an embodiment of the present invention.

FIG. 2 is a perspective view of an electromagnetic relay application device of the present invention.

FIG. 3 is a sound pressure level measuring method.

FIG. 4 is a characteristic diagram showing a relationship between a coating amount of a shock absorbing material and a measured sound pressure level.

FIG. 5 is a characteristic diagram showing the relationship between the amount of impact absorbing material applied and the measured sound pressure level in a circuit board mounted state.

FIG. 6 is a characteristic diagram showing the relationship between the application area of the shock absorber on the surface of the circuit board and the measured sound pressure level.

FIG. 7 is a perspective view of a conventional electromagnetic relay.

[Explanation of symbols]

 1 core 2 coil 3 spool 4 yoke 5 armature 6 case 7 hinge spring 8 movable spring 9a fixed contact 9b fixed contact 10 movable contact 11 boss 12a terminal 12b terminal 12c terminal 13 electromagnetic relay 20a shock absorber 20b shock absorber 20c shock absorber 20d shock absorber 30 circuit board 31 precision sound level meter 32 anechoic box 33 microphone

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Seiichi Machida 5-7-1 Shiba, Minato-ku, Tokyo NEC Corporation

Claims (3)

[Claims] 1. An electromagnetic relay including a case that includes at least one set of an electromagnetic mechanism section and an electric contact opening / closing mechanism section and that protects the electromagnetic mechanism section and the electric contact opening / closing mechanism section,
An electromagnetic relay, wherein a shock absorbing material is applied and fixed to at least one surface of the outer surface or the inner surface of the case. 2. The electromagnetic relay according to claim 1, wherein the electromagnetic relay is mounted on a circuit board. 3. An electromagnetic relay applied device, wherein a case of an electromagnetic relay mounted on a circuit board and at least the surface of the circuit board around the case are applied and fixed with a shock absorbing material.