JP6988455B2 - Electromagnetic relay - Google Patents

Description

The present invention relates to an electromagnetic relay that opens and closes an electric circuit by bringing a movable contact and a fixed contact into contact with each other based on magnetic attraction.

Conventionally, an electromagnetic relay has been known as a device for controlling the on / off of an electric circuit. The electromagnetic relay constitutes a magnetic circuit that passes through a fixed core and a yoke based on the energization of the exciting coil, and is provided on the movable contact and non-movable part attached to the shaft by magnetically attracting the movable core together with the shaft. Make contact with the fixed contact and turn on the electric circuit. Further, by stopping the energization of the exciting coil, the magnetic circuit is turned off, and by returning the shaft and the movable core to the resting position side, the movable contact and the fixed contact are separated from each other, and the electric circuit is turned off. A return spring is provided between the fixed core and the movable core so that the shaft and the movable core can be accurately returned to the resting position side.

Patent Document 1 proposes such an electromagnetic relay in which a return spring is used as a magnetic material. The electromagnetic relay proposed in Patent Document 1 has a fixed core and a return spring by arranging the suction surface of the fixed core and the movable core inside the fitting portion of the return spring composed of the movable core and the coil spring. The interference is prevented and the operating voltage is stabilized. The spring is made of a magnetic material to be a part of the magnetic circuit, and the attractive force between the windings can be obtained to reduce the operating voltage.

Japanese Unexamined Patent Publication No. 2012-94435

However, when the return spring is composed of a coil spring, a force is generated inward in the radial direction between the return spring and the movable core adjacent to the coil spring, and the return spring is tilted.

Therefore, the present inventors are studying the application of a conical compression coil spring called a bamboo shoot spring, which is formed by winding a thin plate in a spiral shape as a return spring. Specifically, a bamboo shoot spring composed of a magnetic material is placed between the fixed core and the movable core, and the bamboo shoot spring is contracted when the exciting coil is energized to make the movable contact and the fixed contact. Make a contact. Before the exciting coil is energized, the outermost peripheral side of the bamboo shoot spring is in contact with the fixed core on one direction side in the axial direction, and the innermost peripheral side of the bamboo shoot spring is in contact with the movable core on the other side in the axial direction. Be done. Then, when the exciting coil is energized, the entire area of one end surface of the contracted bamboo shoot spring in the axial direction becomes a contact surface and comes into contact with the movable core, and the entire area of the other end surface in the axial direction becomes a contact surface. Contact the fixed core. In this way, the bamboo shoot spring becomes a part of the magnetic circuit, and it becomes possible to strengthen the attractive force between the movable core and the fixed core.

However, depending on the processing accuracy of the axial tip surface of the bamboo shoot and the inclination of the movable core, the contact surface between the axial end surface of the bamboo shoot spring and the movable core is sufficient when the exciting coil is energized. It may not be possible to obtain it.

In view of the above points, it is an object of the present invention to provide an electromagnetic relay capable of securing a contact area between a return spring and a movable core.

In order to achieve the above object, the electromagnetic relay according to claim 1 is arranged in an exciting coil (12) that forms a magnetic field by energization and in a central hole formed in an inner diameter portion of the exciting coil, and is placed on the exciting coil. The fixed core (13), which constitutes a part of the magnetic circuit formed based on energization, is arranged so as to cover one of the outer peripheral side and the axial end of the exciting coil, and forms a part of the magnetic circuit. A yoke (14) having an opening (142a) formed on one side in the axial direction so as to correspond to the position of the fixed core, and an exciting coil arranged opposite to the fixed core at a position corresponding to the opening. A movable core (15) that is attracted to the fixed core side based on the magnetic attraction when energized to, a movable contact (20) that has a movable contact (23) and operates following the movable core, and an exciting coil. A magnetic circuit composed of a plurality of fixed terminals (24a, 24b) having fixed contacts (25a, 25b) with which the movable contacts come into contact when energized, and a magnetic material that urges the movable core in a direction away from the fixed core. It is provided with a return spring (16), which constitutes a part of the above. In such a configuration, the return spring is composed of a bamboo shoot spring, and one end of the return spring in the axial direction is connected to one side of the movable core on the fixed core side.

According to such a configuration, since one end of the return spring in the axial direction is connected to one surface of the movable core on the fixed core side, it is possible to suppress the return spring from tilting in the axial direction, and the movable core can be prevented from tilting. It is possible to suppress the occurrence of radial positional deviation in which the central axis of the return spring deviates from the central axis of. This makes it possible to make an electromagnetic relay that can secure a contact area between the movable core and the return spring.

The reference numerals in parentheses of each of the above means indicate an example of the correspondence with the specific means described in the embodiment described later.

It is sectional drawing of the electromagnetic relay which concerns on 1st Embodiment. It is a bottom view when the movable core is seen from the lower part of the paper surface of FIG. FIG. 3 is a cross-sectional view showing a state of the electromagnetic relay shown in FIG. 1 when energization of an exciting coil is started. FIG. 3 is a cross-sectional view showing a state of the electromagnetic relay shown in FIG. 1 in the process of energizing the exciting coil and achieving a conduction state. It is sectional drawing which showed the state of the electromagnetic relay shown in FIG. 1 when the exciting coil was energized and became the conduction state. It is sectional drawing of the electromagnetic relay which concerns on 2nd Embodiment. It is sectional drawing which showed the state of the electromagnetic relay shown in FIG. 4 when the exciting coil was energized and became the conduction state. It is sectional drawing of the electromagnetic relay which concerns on 3rd Embodiment. It is sectional drawing which showed the state of the electromagnetic relay shown in FIG. 6 when the exciting coil was energized and became the conduction state. It is sectional drawing of the electromagnetic relay which concerns on 4th Embodiment. It is sectional drawing of the electromagnetic relay which explains as the modification of the 4th Embodiment. It is sectional drawing of the electromagnetic relay which concerns on 5th Embodiment. It is the figure which showed silicon between the axial length of a return spring and the spring reaction force. It is sectional drawing of the electromagnetic relay which concerns on 6th Embodiment. It is sectional drawing of the electromagnetic relay which concerns on 7th Embodiment. It is a bottom view of the movable core described in another embodiment. It is a bottom view of the movable core described in another embodiment. It is a bottom view of the movable core described in another embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each of the following embodiments, the parts that are the same or equal to each other will be described with the same reference numerals.

(First Embodiment)
The electromagnetic relay according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 3.

As shown in FIG. 1, the electromagnetic relay includes a case 11, an exciting coil 12, a fixed core 13, a yoke 14, a movable core 15, a return spring 16, a shaft 17, a base 18, a retaining ring 19, a movable contact 20, and a retaining ring. 21 and a pressure spring 22 are provided.

The case 11 is made of a non-magnetic and non-conductive material such as resin. Each component constituting the electromagnetic relay is housed in the space formed in the case 11.

The exciting coil 12 forms a magnetic field when energized, has a substantially cylindrical shape, and is wound around a bobbin 12a having a hollow cylindrical portion. The exciting coil 12 is energized through an external connection terminal (not shown). The fixed core 13 and the like are arranged in the central hole formed in the inner diameter portion of the exciting coil 12.

The fixed core 13 is made of a magnetic material, and is composed of a substantially columnar member having a size corresponding to the central hole of the exciting coil 12, and constitutes a part of a magnetic circuit. The fixed core 13 has a structure in which a through hole 13a is formed along the central axis, and one end of the shaft 17 is located in the through hole 13a.

The yoke 14 is a magnetic member that surrounds the exciting coil 12. The yoke 14 is arranged so as to cover one of the outer peripheral side and the axial end portion of the exciting coil 12, constitutes a part of the magnetic circuit, and has an opening corresponding to the position of the fixed core 13 on one side in the axial direction. It is configured as if the yoke hole 142a is formed.

In the case of the present embodiment, the yoke 14 has a configuration including a first member 141 and a second member 142. The first member 141 is a member called a stationary, and has a structure in which a plate material made of a magnetic material is bent into a substantially U shape. The first member 141 covers the outer peripheral side of the exciting coil 12 and one end side of the exciting coil 12 in the axial direction. Further, the second member 142 is a member called a top plate, which is made of a magnetic material, is formed of, for example, a circular flat plate or a rectangular flat plate, and covers the other end side of the exciting coil 12 in the axial direction. Further, the second member 142 is arranged so as to face the movable core 15 described later, and is joined to the first member 141.

An opening 141a is formed in the first member 141 at a position corresponding to the fixed core 13, and a part of the fixed core 13 is fitted into the opening 141a to form the fixed core 13 and the first member 141. Are joined. The yoke hole 142a described above is formed in the center of the second member 142 so as to penetrate the second member 142. The shape of the yoke hole 142a, that is, the inner peripheral shape of the second member 142 is a shape corresponding to the movable core 15.

The movable core 15 is a plate-shaped member made of a magnetic material arranged at a position corresponding to the yoke hole 142a in the second member 142. A through hole 15a into which a shaft 17 described later is inserted is formed on the central axis of the movable core 15. The movable core 15 is located at a resting position away from the yoke 14 when the exciting coil 12 is not energized, and magnetically attracts to the yoke 14 side when the exciting coil 12 is energized. Then, it is brought into contact with the second member 142 of the yoke 14. The outer peripheral shape of the movable core 15 has a shape corresponding to the inner peripheral shape of the yoke hole 142a, and the side opposite to the fixed core 13 has a flange shape having a larger diameter than the fixed core 13 side, and the flange-shaped portion thereof. Is in contact with the inner wall surface of the yoke hole 142a.

Further, in the present embodiment, a stopper portion 15b is provided on one surface of the movable core 15 on the return spring 16 side as a configuration for suppressing the return spring 16 from tilting in the axial direction. In the case of the present embodiment, the stopper portion 15b is a portion constituting the connecting portion.

As shown in FIGS. 1 and 2, the stopper portion 15b is composed of a protrusion portion of the movable core 15 that protrudes in an annular shape from one surface on which the return spring 16 is arranged toward the fixed core 13. As will be described later, the stopper portion 15b is fitted to the tip of the return spring 16 having the smallest diameter, and the outer diameter of the stopper portion 15b is movable among the return springs 16 before the stopper portion 15b is fitted. It is equal to or larger than the inner diameter of the tip on the core 15 side.

The return spring 16 is arranged between the fixed core 13 and the movable core 15 and urges the movable core 15 on the opposite side of the fixed core 13. When the exciting coil 12 is energized, the movable core 15 is attracted to the fixed core 13 side against the return spring 16 by the electromagnetic attraction force.

Specifically, the return spring 16 is composed of a conical compression coil spring called a bamboo shoot spring, which is formed by winding a thin plate in a spiral shape, and is made of a magnetic material. For example, SPCC (cold rolled steel plate), SK, SUS430, or the like can be used as the magnetic material constituting the return spring 16.

In the case of the present embodiment, the return spring 16 has a movable core such that the tip of the return spring 16 on the smaller diameter side is directed to the movable core 15 side and the tip on the larger diameter side is directed to the fixed core 13 side. It is arranged between the 15 and the fixed core 13. Further, at the tip of the return spring 16 on the smaller diameter side, the stopper portion 15b is fitted in the return spring 16. The axial thickness of the return spring 16 is such that the return spring 16 is brought into contact with both the movable core 15 and the fixed core 13 when the electromagnetic relay is in a conductive state, as will be described later. Therefore, a magnetic circuit is formed between the movable core 15 and the fixed core 13 through the entire winding of the return spring 16, and the conductive state is maintained in a state where the movable core 15 is more strongly attracted by magnetism. Is possible.

As described above, the fixed core 13, the yoke 14, the movable core 15, and the return spring 16 are composed of magnetic materials, and when the exciting coil 12 is energized, the magnetic circuit of the magnetic flux induced by the exciting coil 12 is energized. Is configured.

The shaft 17 is made of, for example, a non-magnetic material, and is made movable integrally with the movable core 15 by being coupled to the movable core 15. More specifically, the shaft 17 is coupled to the movable core 15 in a state of being inserted into the through hole 15a formed in the movable core 15. Then, one end of the shaft 17 protrudes toward the fixed core 13 and enters the through hole 13a formed in the fixed core 13.

Further, a flange portion 17b having an enlarged outer diameter of a part of the shaft 17 is formed at a position corresponding to one surface of the movable core 15 on the fixed core 13 side of the shaft 17. When the exciting coil 12 is energized, the movable core 15 pushes the flange portion 17b, so that the shaft 17 can be moved to the fixed core 13 side.

In the case of the present embodiment, the movable core 15, the shaft 17, the movable contactor 20, and the like are movable portions that are moved forward and backward by energizing and de-energizing the exciting coil 12. These moving parts make up the mover.

The base 18 is made of a non-magnetic insulating material, for example, a resin, and is fixed to the case 11. The base 18 has an opening 18a formed in the center thereof, and the shaft 17 is inserted into the opening 18a. The base 18 is fixed to the case 11 in contact with the yoke 14. The base 18 is provided with a plate-shaped first fixed terminal 24a and a second fixed terminal 24b made of conductive metal. These first fixed terminal 24a and second fixed terminal 24b form a part of the wiring of the electric circuit to be turned on / off by the electromagnetic relay. Further, a first fixed contact 25a is attached to the base 18 so as to be connected to the first fixed terminal 24a, and a second fixed contact 25b is attached so as to be connected to the second fixed terminal 24b. The first fixed contact 25a is arranged to face one movable contact 23, and the second fixed contact 25b is arranged to face the other movable contact 23.

Although not shown, the first fixed terminal 24a and the second fixed terminal 24b are drawn out to the outside of the case 11 so that they can be electrically connected to an external electric circuit. Further, a stopper 18b is provided on one side of the base 18 facing the movable core 15 to restrict the movement of the movable core 15 to the opposite side to the fixed core 13.

The retaining ring 19 is arranged on the side of the shaft 17 opposite to the fixed core 13 from the base 18, and is fixed by being fitted to the shaft 17. The retaining ring 19 positions the movable contactor 20 in the axial direction of the shaft 17.

The movable contact 20 is operated to follow the movable core 15, and is composed of a plate-shaped member made of conductive metal, and has two movable contacts 23 made of conductive metal, for example, at symmetrical positions about the shaft 17. It is fixed. The movable contact 20 is arranged on the opposite side of the shaft 17 from the base 18 to the fixed core 13 by inserting the shaft 17 into the insertion hole 20a formed in the center. One surface of the movable contact 20 on the fixed core 13 side is in contact with the retaining ring 19, and the movable contact 20 is positioned and arranged at the position of the retaining ring 19.

The retaining ring 21 is fitted to the end of the shaft 17 opposite to the fixed core 13. The pressure contact spring 22 is arranged between the retaining ring 21 and the movable contact 20 and urges the movable contact 20 to the retaining ring 19 side, that is, to the first fixed contact 25a and the second fixed contact 25b side. ing. Therefore, even if vibration or the like occurs, the connection between the movable contact 23 and the first fixed contact 25a and the second fixed contact 25b is maintained.

The electromagnetic relay according to the present embodiment is configured by the above structure.

Next, the operation and effect of the electromagnetic relay according to the present embodiment will be described with reference to FIGS. 1 and 3 (a) to 3 (c). The solid line arrows shown in FIGS. 3 (a) to 3 (c) and the direction display symbols on the return spring 16 indicate the direction of the magnetic flux flow, and the broken line arrows indicate the direction of magnetic attraction. Shows.

First, as shown in FIG. 1, when the exciting coil 12 is not energized and the exciting coil 12 is not energized, the magnetic attraction force is not generated by the exciting coil 12, so that the movable core 15 is based on the spring force of the return spring 16. It is in a state away from the fixed core 13. The movable contact 23 is also separated from the first fixed contact 25a and the second fixed contact 25b. Therefore, the target electric circuit to be on / off controlled by the electromagnetic relay is in the off state.

When the exciting coil 12 is energized, as shown in FIGS. 3A and 3B, the movable core 15 is attracted to the fixed core 13 side against the return spring 16 by the electromagnetic attraction force, and the shaft 17 and the movable core 17 are movable. The contact 20 follows the movable core 15 and moves toward the fixed core 13. Then, as shown in FIG. 3C, the movable contact 23 comes into contact with the first fixed contact 25a and the second fixed contact 25b, and the space between the first fixed contact 25a and the second fixed contact 25b is electrically connected. It becomes a conductive state.

On the other hand, when the energization of the exciting coil 12 is released, the movable core 15, the shaft 17, and the movable contact 20 are urged by the return spring 16 to be moved to the opposite side of the fixed core 13. As a result, as shown in FIG. 1, the movable contact 23 is separated from the first fixed contact 25a and the second fixed contact 25b, and the first fixed contact 25a and the second fixed contact 25b are electrically cut off from each other. Become.

Here, in order to make the return spring 16 serve as a part of the magnetic circuit when performing the above operation, the return spring 16 is made of a magnetic material.

However, as long as the return spring 16 is made of a magnetic material, a force (hereinafter referred to as side force) is generated between the return spring 16 and other magnetic material parts, and the inclination of the movable core 15 and the return spring 16 is increased. It becomes a factor. Therefore, it is preferable that the return spring 16 has a structure capable of reducing the side force while being used as a magnetic circuit.

Therefore, as described above, in the present embodiment, the return spring 16 is composed of a conical compression coil spring called a bamboo shoot spring.

When the movable core 15 is magnetically attracted to the fixed core 13 side by energizing the exciting coil 12, a magnetic flux flows along the winding of the return spring 16 composed of a bamboo shoot spring. At this time, since the return spring 16 has a thin plate shape, leakage flux from the return spring 16 is generated between the fixed core 13 and the return spring 16 and between the return spring 16 and the movable core 15. Using this leakage flux, a magnetic attraction force is generated between the fixed core 13 and the return spring 16 and between the return spring 16 and the movable core 15, and a "force for contracting the spring" can be obtained. That is, the apparent spring reaction force can be weakened only while the exciting coil 12 is energized.

When the movable core 15 is completely sucked, a magnetic flux flows in the height direction of the return spring 16, but acts on the movable core 15 and the return spring 16 from the start of magnetic suction to the end of the magnetic suction of the movable core 15. The suction force has no radial component. Therefore, it is possible to reduce the side force. As described above, by applying the bamboo shoot spring as the return spring 16, the side force can be reduced, so that the inclination of the movable core 15 and the return spring 16 can be suppressed.

Further, the thickness of the return spring 16 in the axial direction is set so that the return spring 16 is brought into contact with both the movable core 15 and the fixed core 13 when the electromagnetic relay is in a conductive state. Therefore, a magnetic circuit is formed between the movable core 15 and the fixed core 13 through the entire winding of the return spring 16, and the conductive state is maintained in a state where the movable core 15 is more strongly attracted by magnetism. Is possible.

However, even if the thickness of the return spring 16 in the axial direction is set as described above, the return spring 16 and the movable core 15 may be used in the conduction state depending on the processing accuracy of the axial tip surface of the return spring 16 and the inclination of the movable core. There is a possibility that the contact area between them will not be sufficient.

Therefore, in the case of the present embodiment, the movable core 15 is provided with a stopper portion 15b so that the stopper portion 15b is fitted to the tip of the return spring 16 on the smaller diameter side. Due to such a configuration, the movable core 15 and one end of the return spring 16 are connected to each other, the diameter change of one end of the return spring 16 is regulated by the stopper portion 15b, and the contact between the movable core 15 and the return spring 16 is restricted. The area can be secured. Further, by providing the stopper portion 15b, the movable core 15 and the return spring 16 can be brought into surface contact with each other. Further, the return spring 16 can be brought into contact with the stopper portion 15b by utilizing the force of winding the return spring 16 inward in the radial direction, that is, the force of maintaining the shape. Therefore, it is possible to secure a contact area between the movable core 15 and the return spring 16.

Further, since the stopper portion 15b is fitted to the tip of the return spring 16 on the smaller diameter side, it is possible to suppress the return spring 16 from tilting in the axial direction, and the return spring 16 returns from the central axis of the movable core 15. It is possible to suppress the occurrence of radial positional deviation in which the central axis of the spring 16 is displaced. As a result, the spring force of the return spring 16 can be made to act evenly on the central axes of the fixed core 13 and the movable core 15, the inclination of the movable core 15 can be suppressed, and the variation in each performance can be suppressed. It becomes.

As described above, in the present embodiment, the return spring 16 is made of a magnetic bamboo shoot spring. This makes it possible to reduce the side force while allowing the return spring 16 to be used as a constituent of the magnetic circuit. A stopper portion 15b is provided for the movable core 15 so as to be fitted to the tip of the return spring 16 on the smaller diameter side. This makes it possible to make an electromagnetic relay that can secure a contact area between the movable core 15 and the return spring 16.

(Second Embodiment)
The second embodiment will be described. Since the present embodiment is the same as the first embodiment in that the configuration of the fixed core 13 is changed from the first embodiment, only the parts different from the first embodiment will be described.

As shown in FIG. 4, the electromagnetic relay of the present embodiment has a configuration in which the fixed core 13 is provided with an extension portion 13b. The extending portion 13b is formed on the surface of the fixed core 13 facing the movable core 15, and has a structure that protrudes in a columnar shape toward the movable core 15 side. The central axis of the extension portion 13b is coaxial with the central axis of the portion of the fixed core 13 other than the extension portion 13b, and the through hole 13a includes the extension portion 13b on these central axes. It is formed so as to penetrate the fixed core 13.

The axial dimension of the extension portion 13b is arbitrary, but when the excitation coil 12 is not energized, a part of the extension portion 13b enters the inside of the innermost inner diameter side of the return spring 16 and the extension portion 13b is not energized. It is designed to be smaller than the axial thickness of the return spring 16.

By providing such an extension portion 13b, it is possible to extend the region of the fixed core 13 in which the shaft 17 is slid. Therefore, the inclination of the shaft 17 and the movable core 15 can be further suppressed, and the variation in each performance can be further suppressed.

Further, as shown by an arrow in FIG. 4, when the exciting coil 12 is energized, a magnetic flux flowing through the extension portion 13b is generated, and this magnetic flux causes the magnetic flux to flow from the fixed core 13 to the return spring 16. The amount can be increased. Therefore, the amount of magnetic flux in the entire magnetic circuit is increased and the electromagnetic attraction force is increased, so that the movable core 15 can be attracted more strongly.

Further, as shown by an arrow in FIG. 5, when the electromagnetic relay is in a conductive state, a magnetic flux flowing from the tip of the extending portion 13b to the movable core 15 is generated, and the extending portion 13b and the movable core 15 are connected to each other. A magnetic attraction force can be obtained even in the meantime. Therefore, a stronger connection is possible, and it is possible to suppress the occurrence of contact separation in which the movable contact 23 is separated from the first fixed contact 25a and the second fixed contact 25b, resulting in a more reliable electromagnetic relay. can do.

Further, since the movable core 15 is provided with the stopper portion 15b, the same effect as that of the first embodiment can be obtained, and further, the inner wall surface of the innermost portion of the return spring 16 and the outer peripheral surface of the extending portion 13b. It is also possible to obtain the effect that the gap between the two can be kept constant while keeping the distance between the two and the predetermined distance or less. Therefore, it is possible to suppress the concentration of the magnetic flux generated when the distance between the return spring 16 and the extension portion 13b is locally reduced while obtaining the electromagnetic attraction force due to the magnetic flux flowing through the extension portion 13b to the return spring 16. Since the concentration of the magnetic flux can be suppressed, the return spring 16 can be suppressed from being attracted to the fixed core 13 and coming into contact with or sticking to the fixed core 13.

Further, since the stopper portion 15b can suppress the inner diameter of the return spring 16 from shrinking, when the return spring 16 is expanded and contracted with the movement of the movable core 15, the inner wall surface of the return spring 16 and the extending portion 13b Can be prevented from touching. Therefore, friction due to contact between the return spring 16 and the extension portion 13b can be suppressed, the electromagnetic relay can be operated more smoothly, and wear of the extension portion 13b and the return spring 16 can be suppressed.

(Third Embodiment)
The third embodiment will be described. This embodiment is a modification of the configuration of the stopper portion 15b corresponding to the connecting portion with respect to the second embodiment, and the other parts are the same as those of the second embodiment. Only explain.

As shown in FIG. 6, in the electromagnetic relay of the present embodiment, the radial dimension of the stopper portion 15b is reduced with respect to the first embodiment, and the space between the inner peripheral surface of the stopper portion 15b and the outer peripheral surface of the stopper portion 15b is reduced. The recess 15c is formed in the recess.

Further, an annular protrusion 13c is formed on the tip surface of the extension 13b facing the movable core 15. The radial width of the protrusion 13c is set to be equal to or less than the distance between the inner peripheral surface of the stopper portion 15b and the outer peripheral surface of the stopper portion 15b. Therefore, as shown in FIG. 7, when the movable core 15 is moved to the fixed core 13 side most, the protrusion 13c enters the recess 15c so that the protrusion 13c and the stopper 15b mesh with each other. Can be done.

With such a configuration, it is possible to suppress an increase in the weight of the movable core 15 by the amount that the radial dimension of the stopper portion 15b is reduced. Therefore, the same effect as that of the second embodiment can be obtained while suppressing the increase in the weight of the movable portion.

(Fourth Embodiment)
The fourth embodiment will be described. In the present embodiment, the configuration of the stopper portion 15b corresponding to the connecting portion is changed from the first to third embodiments, and the other parts are the same as those in the first to third embodiments. -Only the parts different from the third embodiment will be described. Here, the case where the structure of the stopper portion 15b is changed will be described with respect to the structure in which the extension portion 13b is provided and the protrusion portion 13c is inserted into the recess 15c as in the third embodiment. It can also be applied to the structure of the embodiment.

As shown in FIG. 8, in the electromagnetic relay of the present embodiment, the movable core 15 is composed of two members, a first member 15d and a second member 15e. The first member 15d is composed of a disk-shaped plate member 15f made of a magnetic material such as SPCC, and a stopper portion 15b is formed on the side of the plate member 15f opposite to the second member 15e. The second member 15e is also made of a disk-shaped member made of a magnetic material such as SPCC. Then, one surface of the first member 15d opposite to the stopper portion 15b is attached to one surface of the second member 15e on the fixed core 13 side to be integrated, and the movable core 15 is configured.

As described above, even if the portion of the movable core 15 that constitutes the stopper portion 15b is composed of a separate member from the remaining portion, the same effect as that of each of the above embodiments can be obtained.

(Modified example of the fourth embodiment)
In the fourth embodiment, the first member 15d has a structure that overlaps the entire surface of the fixed core 13 side of the second member 15e, but the structure shown in FIG. 9 may be used. That is, the entire area inside the stopper portion 15b of the first member 15d is the opening portion 15g, and the protrusion portion 15h corresponding to the opening portion 15g is provided on one surface of the second member 15e on the fixed core 13 side. Then, the protruding portion 15h is fitted into the opening portion 15g. Even with such a structure, the same effect as that of the fourth embodiment can be obtained.

In the case of the example of FIG. 9, the tip of the stopper portion 15b is projected from the tip of the protruding portion 15h, and the recess 15c is formed by the stopper portion 15b and the protruding portion 15h. There is. Therefore, the effect of the third embodiment can be obtained.

(Fifth Embodiment)
A fifth embodiment will be described. This embodiment is also the same as the first to fourth embodiments in that the configuration of the connecting portion is changed with respect to the first to fourth embodiments. Only the different parts will be described. Here, a case where the configuration of the stopper portion 15b is changed in the configuration including the extension portion 13b as in the second embodiment will be described, but the structure of the first, third, and fourth embodiments will also be described. Applicable.

As shown in FIG. 10, in the electromagnetic relay of the present embodiment, a groove portion 15i is formed on one surface of the movable core 15 on the fixed core 13 side, and the groove portion 15i functions as a connecting portion. The groove portion 15i has an annular shape corresponding to the tip of the return spring 16 on the smaller diameter side, and one end side of the return spring 16 in the axial direction is fitted in the groove portion 15i.

By fitting the one end side of the return spring 16 in the axial direction into the groove portion 15i in this way, the groove portion 15i functions as a connecting portion, and it is possible to prevent the inner diameter of the return spring 16 from shrinking. Therefore, the same effect as that of the first to fourth embodiments can be obtained.

Further, the thickness of the return spring 16 is constant from the inner diameter side to the outer diameter side. By doing so, the restoring force when the return spring 16 is compressed, that is, the variation in the spring reaction force can be suppressed by the amount that a part of the return spring 16 has entered the groove portion 15i.

That is, as shown in FIG. 11, the spring reaction force of the return spring 16 has a characteristic that the length in the axial direction of the return spring 16 increases sharply when the length is reduced to near the thickness of the return spring 16. There is. Therefore, if the return spring 16 is designed to be shrunk to the thickness in the axial direction when the movable core 15 is moved to the fixed core 13 side most, the spring reaction force due to individual differences of the return spring 16 due to processing variation or the like. The variation becomes large. If the spring reaction force of the return spring 16 is too large, it may be difficult to magnetically attract the movable core 15.

However, since a part of the return spring 16 is inserted in the groove portion 15i, the return spring 16 cannot be contracted to the thickness in the axial direction, and can be contracted only to a region where the variation in the spring reaction force is relatively small. Therefore, even if there are individual differences in the return spring 16, it is possible to suppress variations in the spring reaction force when the return spring 16 is compressed, and it becomes difficult to magnetically attract the movable core 15. It can be avoided to occur.

(Sixth Embodiment)
The sixth embodiment will be described. This embodiment is also the same as the first to fourth embodiments in that the configuration of the connecting portion is changed with respect to the first to fourth embodiments. Only the different parts will be described. Here, a case where the configuration of the stopper portion 15b is changed in the configuration including the extension portion 13b as in the second embodiment will be described, but the structure of the first, third, and fourth embodiments will also be described. Applicable.

As shown in FIG. 12, in the electromagnetic relay of the present embodiment, a connecting portion is configured by directly connecting the tip of the return spring 16 on the smaller diameter side to one surface of the fixed core 13 side of the movable core 15. There is. The return spring 16 and the movable core 15 may be connected by welding or the like, but here, a case where the return spring 16 and the movable core 15 are connected via an adhesive 30 is shown. Then, the adhesive 30 is applied to the side surface of the innermost portion of the return spring 16 so that the movable core 15 and the return spring 16 are magnetically connected, that is, they are in direct contact with each other. I have to.

In this way, even if the connecting portion is configured by directly connecting the return spring 16 and the movable core 15, the same effect as that of the first to fourth embodiments can be obtained.

(7th Embodiment)
The seventh embodiment will be described. In this embodiment, the configuration of the return spring 16 and the like is changed with respect to the first, second, fourth to sixth embodiments, and the other embodiments are the first, second, fourth to sixth embodiments. Therefore, only the parts different from the first, second, fourth to sixth embodiments will be described. Here, a case where the configuration of the return spring 16 and the like is changed in the configuration including the extension portion 13b as in the second embodiment will be described, but the structure of the first, fourth to sixth embodiments will be described. Can also be applied.

As shown in FIG. 13, in the present embodiment as in the second embodiment, the return spring 16 is made of a bamboo shoot spring, but the tip on the smaller diameter side is directed toward the fixed core 13 side, and the diameter is increased. The tip on the larger side is oriented toward the movable core 15 side.

Further, a stopper portion 15b is formed on one surface of the movable core 15 on the fixed core 13 side. The inner diameter of the stopper portion 15b is the same as or slightly smaller than the outer diameter of the tip of the return spring 16 before being fitted into the stopper portion 15b on the movable core 15 side, that is, the tip on the side having the largest diameter. As a result, the tip of the return spring 16 on the side having the largest diameter is fitted into the stopper portion 15b. Then, at the tip of the return spring 16 on the smaller diameter side, the extension portion 13b is fitted in the return spring 16. As a result, the inner wall surface and the tip surface of the return spring 16 are brought into contact with the extending portion 13b.

In this way, the direction of the return spring 16 can be directed in the direction opposite to that of the second embodiment. With such a configuration, the return spring 16 and the stopper portion 15b are brought into contact with each other, so that the contact area between the movable core 15 and the return spring 16 can be secured.

Further, the stopper portion 15b and the extension portion 13b suppress the inclination and radial position deviation of the return spring 16 in the axial direction, and the stopper portion 15b suppresses the radial spread of the return spring 16 so that the extension portion is extended. The 13b also suppresses the reduction of the return spring 16 inward in the radial direction. Therefore, the spring force of the return spring 16 can be made to act evenly on the central axes of the fixed core 13 and the movable core 15, the inclination of the movable core 15 can be suppressed, and the variation in each performance can be suppressed. Become.

In the case of a structure in which the extension portion 13b is not provided as in the first embodiment, the same configuration as the stopper portion 15b and the groove portion 15i is provided on one surface of the fixed core 13 on the movable core 15 side. It may be provided, or the return spring 16 and the fixing core 13 may be directly connected with an adhesive or the like.

(Other embodiments)
The present invention is not limited to the above-described embodiment, and can be appropriately modified within the scope of the claims.

In the first to fourth and seventh embodiments, the movable core 15 is viewed from the fixed core 13 side so that the stopper portion 15b has an annular shape, but other shapes may be used. For example, as shown in FIG. 14, the stopper portion 15b may have a regular octagonal shape. Of course, the shape is not limited to an octagon, and other polygonal shapes such as a hexagon may be used. In the first to fourth embodiments, when the stopper portion 15b is polygonal, the length of the diagonal line passing through the central axis of the movable core 15 is the same as or slightly equal to the inner diameter of the tip of the return spring 16 on the movable core 15 side. It should be enlarged. In the seventh embodiment, when the stopper portion 15b is polygonal, the shortest distance from the central axis of the movable core 15 to each side is the same as or slightly equal to the outer diameter of the tip of the return spring 16 on the movable core 15 side. It suffices if it is made smaller.

Further, the stopper portion 15b may have a shape in which a part of an annular shape or a polygon is cut out, or a shape divided into a plurality of parts in a broken line shape. For example, as shown in FIG. 15, a C-shaped shape obtained by cutting out a part of an annular shape, or as shown in FIG. 16, an annular shape divided into a plurality of rings can be formed. Of course, it may be a dot-shaped polygonal shape divided into a plurality of parts. In that case, it is preferable that each corner portion of the polygonal shape is formed as a part of the stopper portion 15b. That is, the stopper portion 15b may have a structure capable of regulating the change in diameter at one end of the return spring 16 when the exciting coil 12 is energized.

Further, although the return spring 16 is entirely made of a magnetic material, since a part of the magnetic circuit may be formed by the return spring 16, a part of the return spring 16 may be made of a material other than the magnetic material.

12 Exciting coil 13 Fixed core 14 Yoke 15 Movable core 15b Stopper part 15i Groove part 16 Return spring 20 Movable contact 23 Movable contacts 25a, 25b 1st and 2nd fixed contacts

Claims (11)

An exciting coil (12) that forms a magnetic field by energization,
A fixed core (13) arranged in a central hole formed in the inner diameter portion of the exciting coil and forming a part of a magnetic circuit formed based on energization of the exciting coil.
It is arranged so as to cover one of the outer peripheral side and the axial end portion of the exciting coil, constitutes a part of the magnetic circuit, and is opened on one side of the axial direction so as to correspond to the position of the fixed core. The yoke (14) on which the portion (142a) was formed and
A movable core (15) that is arranged to face the fixed core at a position corresponding to the opening and is attracted to the fixed core side based on a magnetic attraction when the exciting coil is energized.
A movable contact (20) having a movable contact (23) and operating following the movable core,
A plurality of fixed terminals (24a, 24b) having fixed contacts (25a, 25b) with which the movable contacts come into contact when the exciting coil is energized.
A return spring (16) that urges the movable core in a direction away from the fixed core and constitutes a part of the magnetic circuit by being composed of a magnetic material is provided.
The return spring is an electromagnetic relay composed of a bamboo shoot spring, and one end in the axial direction of the return spring is connected to one surface of the movable core on the fixed core side. In the return spring, the tip of the return spring on the smaller diameter side is directed toward the movable core side.
The portion where the movable core and the return spring are connected is used as a connecting portion.
The connecting portion is formed on one surface of the movable core on the fixed core side, and is fitted to the tip of the return spring on the smaller diameter side, so that the return spring is compressed when the exciting coil is energized. The electromagnetic relay according to claim 1, which is a stopper portion (15b) that regulates a change in the diameter of the tip of the return spring on the smaller diameter side. The electromagnetic relay according to claim 2, wherein the stopper portion is composed of a protrusion portion of the movable core that protrudes toward the fixed core side from one surface on which the return spring is arranged. The electromagnetic relay according to claim 3, wherein the stopper portion is any one of an annular shape, a polygonal shape, a dot-shaped annular shape divided into a plurality of parts, and a dot-shaped polygonal shape. The fixed core has a columnar extending portion (13b) that protrudes from one surface of the fixed core on the movable core side toward the movable core side and enters the inside of the innermost inner diameter side of the return spring.
The stopper portion regulates a change in the diameter of the tip of the return spring on the smaller diameter side, so that the stopper portion is between the inner wall surface of the tip of the return spring on the smaller diameter side and the outer peripheral surface of the extension portion. The electromagnetic relay according to any one of claims 2 to 4, which constitutes a certain gap. The fixed core has a columnar extending portion (13b) that protrudes from one surface of the fixed core on the movable core side toward the movable core side and enters the inside of the innermost inner diameter side of the return spring.
The electromagnetic relay according to claim 2 or 3, wherein the stopper portion has an annular shape, and the outer diameter of the stopper portion is larger than the outer diameter of the extension portion. The electromagnetic wave according to claim 6, wherein the outer diameter of the stopper portion is equal to or larger than the inner diameter of the inner diameter of the tip of the return spring having the smallest diameter in the state before the stopper portion is fitted. relay. The portion where the movable core and the return spring are connected is used as a connecting portion.
The electromagnetic relay according to claim 1, wherein the connecting portion is a groove portion (15i) formed on one surface of the movable core on the fixed core side and into which one end in the axial direction of the return spring is fitted. The portion where the movable core and the return spring are connected is used as a connecting portion.
A claim in which one end of the return spring in the axial direction is connected to one surface of the movable core on the fixed core side while being directly contacted by welding or an adhesive (30) to form the connecting portion. Item 1. The electromagnetic relay according to item 1. In the return spring, the tip of the return spring on the larger diameter side is directed toward the movable core side.
The portion where the movable core and the return spring are connected is used as a connecting portion.
The connecting portion is formed on one surface of the movable core on the fixed core side, and the tip of the return spring on the larger diameter side is fitted so that the return spring is compressed when the exciting coil is energized. The electromagnetic relay according to claim 1, which is a stopper portion (15b) that regulates a change in the diameter of the tip of the return spring on the larger diameter side. 10. Claim 10 that the inner diameter of the stopper portion is the same as or smaller than the outer diameter of the tip of the return spring having the largest diameter side before the return spring is fitted into the stopper portion. The electromagnetic relay described in.

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