JPH11273533A - Electromagnetic relay - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lengthen the mechanical and electric service life, and improve productivity by arranging a projection in a movable block rotated by an electromagnet block, and regulating a position by bringing the projection into pressure contact with the back face intermediate part at overshoot time of a movable contact piece projecting from the movable block. SOLUTION: A movable block 30 by integrally forming a movable iron piece 32 on a back face and a movable contact piece 33 in parallel under it, is rotated on the basis of excitation and demagnetization of an electromagnet block so that a movable contact point 33a projected in the free end part of the movable contact piece 33 is contacted with and separated from a normally opening fixed contact point 14a and a normally closed fixed contact point 15a. A position regulating projection 34a capable of abutting to a back face of the movable contact piece 33 is arranged on the outside edge part outward surface of the projecting part 34 of a main body 31 of this movable block 30. A position is regulated by bringing this projection 34a into pressure contact with the back face central part of the movable contact piece 33 when overshoot time of the movable contact piece 33. Therefore, a deflection angle of the base part of the movable contact piece 33 projecting from the main body 31 of the movable block is reduced to prevent a stress concentration as well as to prevent chattering.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic relay,
The present invention relates to a long-life electromagnetic relay.

[0002]

2. Description of the Related Art Conventionally, as an electromagnetic relay, for example, there is an electromagnetic relay having a configuration shown in FIGS. That is, it is an electromagnetic relay in which the electromagnet block 3, the movable block 4, and the like are accommodated in an internal space formed by the base 1 and the case 2. Electromagnetic block 3 mounted and fixed on base 1
The iron core 3c is inserted into a center hole of a spool 3b around which a coil 3a is wound, and one protruding end is used as a magnetic pole portion, and the other protruding end is fixed to a bent yoke 5 by caulking. The movable block 4 integrally formed by disposing the movable contact piece 6 and the movable iron piece 7 in substantially non-contact with each other is rotatably supported by the horizontal tip of the yoke 5 via a coil spring 8. I have. Then, the excitation of the electromagnet block 3
When the movable iron piece 7 of the movable block 4 is attracted to and separated from the magnetic pole portion of the iron core 3c by demagnetization, the movable block 4 rotates around the horizontal tip of the yoke 5 against the spring force of the coil spring 8. . The movable contact 6a provided at the free end of the movable contact piece 6 alternately comes into contact with and separates from the normally closed fixed contact 6b or the normally open fixed contact 6c to open and close the electric circuit.

[0003]

In this type of electromagnetic relay, the movable contact piece 6 and the lead wire 9 are connected by soldering. However, from the viewpoint of protection of the global environment, the productivity of the connection portion is improved. Therefore, the connection structure is formed by welding and connecting the two without using solder. Further, in this connection structure, the connection portion is covered with a molding resin material for the purpose of preventing disconnection of the connection portion, that is, disconnection due to tensile force, bending force or the like applied to the lead wire 9. For this reason, the length dimension of the movable contact piece 6 must be shortened.

However, the movable contact piece having a short length as described above operates as shown in FIGS. 8 (a) to 8 (d). In particular, the movable block 4 is overloaded by inertia during the return operation. The shooting state (FIG. 8C) is reached. As a result, the movable contact piece 6 protruding from the movable block body 4a.
Greatly bends, and stress concentrates on the base thereof, so that fatigue fracture easily occurs and the mechanical life is short. In addition, the return bounce time during the return operation is prolonged due to the shortening of the movable contact piece 6, and so-called chattering is likely to occur. For this reason, an arc is generated between the contacts during the return operation, and the contacts are easily worn, so that there is a problem that the electrical life is short.

To solve these problems, for example, the gap between the movable contact piece 6 and the movable block body 4a is reduced,
It is conceivable to reduce the displacement amount of the movable contact piece 6.
However, in this method, a mold such as a thin side core is required for molding, and the mold life is shortened, so that there is a problem that productivity is reduced.

In view of the above problems, an object of the present invention is to provide an electromagnetic relay having a long mechanical and electrical life and a high productivity.

[0007]

In order to achieve the above object, an electromagnetic relay according to the present invention comprises a movable block formed by integrally integrating a movable iron piece and a movable contact piece in a non-contact state substantially in parallel with each other. An electromagnetic relay, which rotates based on excitation and demagnetization and contacts and separates a movable contact provided at a free end of a movable contact piece protruding from the movable block with a fixed contact. The protrusion that presses against the middle part of the back of the contact piece and regulates the position,
The structure is provided on the movable block.

The movable block may be one in which a movable iron piece separately formed by insert molding is integrated with a movable contact piece formed primarily by secondary molding. The protrusion may be provided on a protrusion of a movable block formed by covering one end of the movable iron piece with a synthetic resin material.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings of FIGS. That is, as shown in FIG. 1, the electromagnetic relay according to the present embodiment
Base 10, electromagnet block 20, and movable block 3
0 and a case 40.

The base 10 is substantially in the shape of a rectangular plate, and a pair of pedestals 12, 1 facing each other with a groove in the vicinity of one end thereof.
3 are formed. The pedestals 12 and 13 are provided with slits (not shown) at a predetermined pitch in a direction perpendicular to the paper surface. The fixed contact terminals 14 and 15 are press-fitted so as to face each other at each position defined by the slit. The normally open fixed contact 14a and the normally closed fixed contact 15a provided at the upper ends of the fixed contact terminals 14, 15 are opposed to each other at a predetermined interval.

In the electromagnet block 20, an iron core 23 is inserted into a center hole of a spool 22 around which a coil 21 is wound, and one protruding end is used as a magnetic pole part 23a, and the other protruding end is bent into a substantially L-shape. The yoke 24 is caulked and fixed to the vertical portion 24a. And this electromagnet block 20
The flange 22a of the spool 22 and the vertical portion 24a of the yoke 24 are pressed into the base 10 and fixed. The coil 21 is electrically connected to the coil terminal 16 via a relay terminal 25 press-fitted into the spool 22.

The movable block 30 is formed by arranging a movable iron piece 32 and a movable contact piece 33 substantially in parallel in a non-contact state and insert-molding the movable block main body 31 (FIG. 2).
(A), (b)). The movable contact 33a is provided at the free end.
The movable contact piece 33 having a lead wire 35
Is electrically connected to the movable contact terminal 17 via Further, of the protrusions 34 of the movable block main body 31 formed by covering the lower end of the movable iron piece 32 with a synthetic resin material, the lower end edge of its outward surface can be brought into contact with the back surface of the movable contact piece 33. The position regulating projection 34a is provided. The protrusion 34a presses against the middle part of the rear surface of the movable contact piece 33 during overshoot during the return operation to regulate the position of the movable contact piece 33. For this reason, the projection 34a can reduce the bending angle at the base of the movable contact piece 33 protruding from the movable block main body 31, thereby preventing stress concentration and so-called chattering. Then, the movable block 30 is moved to the horizontal tip portion 24 of the yoke 24.
By rotatably supporting the movable contact b, the movable contact 33a faces the normally-open fixed contact 14a and the normally-closed fixed contact 15a alternately so as to be able to come and go. Further, the movable contact piece 33 is biased outward by locking the uppermost end of the movable iron piece 32 to the electromagnet block 20 via the coil spring 36.

The case 40 has a substantially rectangular parallelepiped shape which can be fitted to the base 10 and has a positioning holding portion 4 on its ceiling surface.
1 is protruded. When the case 40 is assembled to the base 10, the positioning presser 41 is used to hold the horizontal tip 24 of the yoke 24 assembled to the electromagnet block 20.
b. As a result, the electromagnet block 20 is sandwiched between the base 10 and the case 40 from above and below and is stabilized.

Next, the operation of the electromagnetic relay having the above configuration will be described. First, when no voltage is applied to the coil 21 of the electromagnet block 20, the movable block 30 is urged in the counterclockwise direction in FIG. Are in contact with the normally closed fixed contact 15a.

When a voltage is applied to the coil 21 to excite it, the magnetic pole portion 23a of the iron core 23 attracts the movable iron piece 32, so that the movable block 30 resists the spring force of the coil spring 36, and , Rotate clockwise. Therefore, after the movable contact 33a contacts the normally-open fixed contact 14a (FIG. 4A), the movable iron piece 32 is moved to the magnetic pole portion 23 of the iron core 23.
Adsorb to a.

Next, when the application of the voltage to the coil 21 is stopped and the above-mentioned excitation is released, the movable block 30 is rotated in the reverse direction by the spring force of the coil spring 36. Therefore, the movable contact 33a is separated from the normally-open fixed contact 14a and returns (FIG. 4B). Then, after the movable contact 33a contacts the normally closed fixed contact 15a, the movable block 30 is further rotated by the inertial force to be in an overshoot state, and the protrusion 34a of the movable block 30 Crimp. For this reason, the base of the movable contact piece 33 does not bend at a large angle as in the conventional example. Further, since the projection 34a is pressed against and pressed against the middle portion of the back surface of the movable contact piece 33, so-called chattering can be prevented. Finally, while the movable contact 33a is in contact with the normally closed fixed contact 15a, the movable block 30 is slightly swung back by the spring force of the movable contact piece 33, and the projection 34a is separated from the movable contact piece 33 to be in a return state. (FIG. 4D).

In the movable block 30, it is not necessary to insert-mold the movable iron piece 32 and the movable contact piece 33 on the movable block main body 31 at the same time. For example, as shown in FIG. 3, after connecting the lead wire 35 to the movable contact piece 33,
Insert molding is performed by primary molding. Then, separately from this, the movable iron piece 32 formed by insert molding may be secondarily formed and integrated. According to the present embodiment, there is an advantage that the positioning between the movable contact piece 33 and the movable iron piece 32 is facilitated, and productivity and component accuracy are improved. Also, the present invention may be applied to a case where the position of the movable contact piece is restricted only during the operation of the position regulating projection. Further, the movable contact does not need to alternately contact and separate from the pair of fixed contacts, and may be configured to contact and separate only one fixed contact.

[0018]

EXAMPLE An operation characteristic during a return operation was measured by providing a projection having a shape determined based on the equation shown in FIG. 6 in the electromagnetic relay shown in FIG. The measurement results are shown in the graph of FIG. (Comparative Example) The operating characteristics were measured in the same manner when no projection was provided. FIG. 9 shows the measurement results. Note that the graphs shown in FIG. 5 or FIG. 9 are measured based on the outward side surface of the movable block. Therefore, in order for the movable contact to reliably contact the normally-closed fixed contact, the displacement must be as shown in FIG.
Alternatively, it is necessary to be about 0.45 or more in FIG. 9, and if it is less than 0.45, it means that the movable contact is separated from the normally closed fixed contact.

By comparing FIG. 5 showing the measurement results of the present embodiment with FIG. 9 of the prior art, the present embodiment has a smaller displacement during the return operation, especially the amplitude at the time of overshoot, than the comparative example. I understand. For this reason, it turned out that the bending angle in the base part of a movable contact piece becomes small, and stress concentration hardly occurs. Further, as is clear from FIG. 5, even if there is a swing back from the overshoot state, the amplitude of the swing back does not become 0.45 or less. Therefore, the movable contact does not separate from the fixed contact, and so-called chattering does not occur. As a result, it was found that no arc was generated between the contacts and the wear of the contacts was significantly reduced, so that the electrical life was extended.

The projections according to the embodiment are formed by roughly calculating based on the equations shown in FIG. However, the equation of FIG. 6 can be used to roughly calculate the shape and position of the projection of the movable block having the most typical component configuration, and is not necessarily limited to the projection of the position and shape derived from this equation. It does not do.

[0021]

As is apparent from the above description, according to the electromagnetic relay of the first aspect of the present invention, after the movable contact comes into contact with the fixed contact, the movable block is further rotated by the inertial force to overshoot. Even in the state, the projection of the movable block presses against the middle part of the rear surface of the movable contact piece to regulate the position. For this reason, the base of the movable contact piece does not bend at a large angle as in the conventional example, and it is difficult for fatigue fracture to occur, so that the mechanical life is extended. In addition, since the projection is pressed against the middle portion of the rear surface of the movable contact piece and indirectly presses the movable contact, so-called chattering does not occur and the electrical life is extended. Further, since the projection is provided on the movable block, there is no need to reduce the gap between the movable block main body and the movable contact piece. For this reason, a mold such as a thin side core is not required, and the life of the mold is prolonged, thereby improving the productivity.

According to the second aspect, the movable block is formed by integrally molding the movable iron piece separately insert-molded with the movable contact piece formed primarily by secondary molding. For this reason, the positioning of the movable contact piece and the movable iron piece becomes easy, and productivity,
Parts accuracy is improved.

According to the third aspect, the protrusion is provided on the protrusion of the movable block formed by covering one end of the movable iron piece with a synthetic resin material. For this reason, since the movable iron piece serves as a core material and the protrusion is hardly deformed, the protrusion is hardly deformed even when the protrusion comes into contact with the movable contact piece. As a result, the position can be regulated as designed, and there is an effect that the operation characteristics do not vary.

[Brief description of the drawings]

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

FIG. 2 shows the movable block shown in FIG.
2A is an enlarged side view, and FIG. 2B is an enlarged sectional view.

FIG. 3 is a modified example of FIG. 2 (b).

FIG. 4 is a schematic diagram for explaining the operation of the movable block shown in FIG.

FIG. 5 is a graph showing an operation of a movable block.

FIG. 6 is a schematic diagram showing an example for specifying the external dimensions of the present embodiment.

FIG. 7 is a cross-sectional view illustrating an electromagnetic relay according to a conventional example.

8 is a schematic diagram for explaining the operation of the movable block shown in FIG.

FIG. 9 is a graph showing an operation of a movable block according to a conventional example.

[Explanation of symbols]

Reference numeral 10: base, 14a: normally open fixed contact, 15a: normally closed fixed contact, 20: electromagnet block, 23: iron core, 23a ...
Magnetic pole part, 30: movable block, 31: movable block body, 32: movable iron piece, 33: movable contact piece, 33a: movable contact, 34: protrusion, 34a: position regulating projection.

Claims (3)

[Claims] A movable block formed by integrating a movable iron piece and a movable contact piece in a substantially non-contact state and substantially parallel to each other, rotates based on excitation and demagnetization of an electromagnet block, and projects from the movable block. A movable contact provided at a free end portion of the electromagnetic relay that contacts and separates from a fixed contact; wherein, when the movable contact piece overshoots, a protrusion that presses against a middle portion of the rear surface of the movable contact piece to regulate the position is formed by the movable block An electromagnetic relay provided in the electromagnetic relay. 2. The electromagnetic relay according to claim 1, wherein the movable block is formed by integrating a separately formed movable iron piece into a primary molded movable contact piece by secondary molding. 3. The electromagnetic relay according to claim 1, wherein the protrusion is provided on a protrusion of the movable block formed by covering one end of the movable iron piece with a synthetic resin material.