JP4858508B2 - Electromagnetic switchgear - Google Patents

Description

The present invention relates to an electromagnetic switching device having a structure in which a contact is opened and closed by an attractive force of an electromagnet and an elastic restoring force of an operating spring piece.

Conventionally, a movable contact that is displaced integrally with the armature is installed facing the movable contact by attracting and separating the armature from the iron core by the attractive force of the electromagnet and the elastic return force of the operating spring piece. Various electromagnetic switchgears that come in contact with and separate from the fixed contact are provided (see, for example, Patent Document 1).

By the way, in recent years, such electromagnetic switchgear is desired to have higher performance, smaller size, and smaller space. In addition, the electromagnetic switching device is required to have high reliability in solder bonding with a printed wiring board. However, if the size is reduced and the space is reduced, the amount of heat generated by the operating spring pieces in the electromagnetic switching device and the contacts and terminals forming the energization path increases. If the heat generation amount exceeds the heat dissipation amount, the internal temperature of the electromagnetic switching device rises, the internal heat is transmitted to the solder joint portion between the electromagnetic switching device and the printed wiring board, and the solder is melted, resulting in poor bonding. There's a problem.

For example, if an electromagnetic switching device used in an electronic control unit (ECU) of an in-vehicle device of an automobile can be further downsized, the ECU can be downsized accordingly, and a part mounting portion in the vehicle can be saved. it can. However, an electromagnetic switch used in an ECU of an on-vehicle device having a large load current such as a headlight or a wiper is particularly concerned about excessive heat generation. Therefore, in order to prevent the above-mentioned joint failure, the demand for low heat generation is increasing with the trend of miniaturization of the electromagnetic switchgear.

On the other hand, for the purpose of enhancing the heat dissipation effect, an electromagnetic switching device having a heat conductive member interposed between the yoke and the inner wall of the case housing the electromagnetic block, or the coil periphery is covered with a heat conductive resin layer. In addition, there is provided an electromagnetic switching device in which the resin layer is in close contact with the inner wall of the case (see Patent Documents 2 and 3).
JP 2006-210289 A JP 2006-331882 A JP-A-10-172407

However, the conventional electromagnetic switch for the purpose of improving the heat dissipation effect has a problem that a new additional heat conduction member or a complicated work process for molding a resin layer is required.

The present invention has been made in view of the above-described reasons, and an object thereof is to provide an electromagnetic switching device that can easily enhance the heat dissipation effect to the outside and suppress the rise in internal temperature without newly increasing the number of members. Is to provide.

In order to achieve the above object, the invention according to claim 1 is arranged so that the armature is attracted to and separated from the iron core by the attraction force of the electromagnet and the elastic return force of the operating spring piece, thereby being displaced integrally with the armature. In the electromagnetic switching device in which the movable contact that contacts and separates from the fixed contact that is installed opposite to the movable contact, the electromagnet, the yoke, the operating spring piece, the armature, the movable contact, An electromagnetic block composed of a bobbin, and a box-shaped case that houses the electromagnetic block, and the electromagnet is disposed through the bobbin and an excitation coil wound around the bobbin. consists of iron core, the yoke is connected to one end of the iron core, through the actuating spring piece supporting said armature swingably, wherein the case, a high thermal conductivity resin member depending on a special filler-containing liquid crystal polymer Is formed, the inner wall surface of the case facing the connection portion between the yoke and the iron core, characterized in that in contact with the at least part of the electromagnetic block.

According to the present invention, the case for housing the electromagnetic block is formed of a special filler-containing liquid crystal polymer that is a resin member having a high thermal conductivity, and the inner side of the case facing the connecting portion between the iron core and the yoke. Since the wall surface is in contact with at least a part of the electromagnetic block, it is possible to easily enhance the heat radiation effect to the outside through the case and suppress an increase in the internal temperature without newly increasing the number of members. .

According to a second aspect of the present invention, in the first aspect of the present invention, a graphite sheet, which is a high thermal conductivity sheet , is interposed between the contact surfaces of the electromagnetic block and the inner wall of the case. It is characterized by being mounted.

According to the present invention , a graphite sheet, which is a high thermal conductivity sheet , is interposed between the contact surfaces of the electromagnetic block and the inner wall of the case, so that a heat dissipation effect is achieved. It can be further increased.

According to a third aspect of the present invention, in the first or second aspect of the present invention, a heat radiating piece extends along the inner wall surface at an end of the operating spring piece coupled to the yoke, and the heat radiating piece is The abutting against the inner wall surface.

According to this invention, among the constituent members of the electromagnetic block, the operating spring piece having a high calorific value is provided with a heat radiating piece extending along the inner wall surface and directly contacting the inner wall surface of the case. Since they are in contact with each other, heat is efficiently conducted, and the heat dissipation effect can be further enhanced.

In the present invention, there is an effect that it is possible to easily enhance the heat dissipation effect to the outside and suppress an increase in internal temperature without newly increasing the number of members.

(Embodiment 1)
Hereinafter, Embodiment 1 of the present invention will be described with reference to FIGS. In the following description, the vertical and horizontal directions are defined in FIG.

As shown in FIGS. 2 to 3, the electromagnetic switching device of the first embodiment includes a case 2 that is formed in a substantially rectangular parallelepiped box shape as a whole, and an electromagnetic block 1 that is housed inside the case 2. . Moreover, the electromagnetic switching device is mounted on the printed wiring board 3 by solder bonding, as shown in FIG.

As shown in FIG. 1, the case 2 includes a body 4 formed in a box shape with an open bottom surface and a base 5 formed in a flat box shape with an open top surface. 5
Is formed from above.

As shown in FIG. 1, a recess 4 a that is recessed in the front direction in the left-right direction is formed on the inner side of the front side wall of the body 4, and further below the recess 4 a. On the inner side of the side wall of the body 4 is formed a locking step 4b that is recessed outwardly over the entire circumference.

As shown in FIGS. 1 and 3, insertion holes 5 a penetrating downward in a rectangular shape are disposed on the inner bottom surface of the base 5 at a total of four locations, approximately the center in the front-rear direction of the left and right ends and the rear. In addition, a pair of insertion portions 5b are provided in front of the left and right ends so as to penetrate in an elongated rectangular shape.

As shown in FIGS. 1 and 2, the electromagnetic block 1 includes an electromagnet 6, a yoke 7, and an operating spring piece 8.
, Armature 9, movable contact 10, and bobbin 11. The electromagnet 6 includes an exciting coil 12 wound around a bobbin 11 and an iron core 13 inserted through the central axis of the bobbin 11.

As shown in FIG. 2, the bobbin 11 is formed in a substantially cylindrical shape as a whole by a resin material having electrical insulation, and has a barrel portion 11 a and upper flange portions 11 b provided at upper and lower ends of the barrel portion 11 a.
And the lower collar portion 11c. The trunk portion 11a is formed in a cylindrical shape, and a through hole 11d formed through the upper and lower end portions is provided on the central axis thereof. And the trunk | drum 11a
The coil 12 is wound around the outer peripheral surface of the steel plate, and the iron core 13 is inserted into the through hole 11d. Upper collar 1
1b has an upper end portion of the body portion 11a formed in a substantially U-shape, and an end portion of the U-shaped opening faces rearward. And the horizontal part 7a of the below-mentioned yoke 7 is fitted by the upper collar part 11b from back. The lower flange portion 11c has a lower end portion of the body portion 11a formed in a rectangular plate shape. Further, the front and rear end portions are opened in front of the approximate center in the front-rear direction of the rectangular plate, and the rectangular plate is used as an upper side wall. A cylindrical portion formed in a substantially rectangular tube shape is formed. Recessed portions 11e recessed rearward are provided at the upper and lower portions of the peripheral left and right ends of the front opening of the lower collar portion 11c, and a fixed contact portion 15 described later is inserted into the recessed portion 11e from the front. A pair of terminal pieces 11f and 11g extending downward is provided at a substantially central portion in the front-rear direction of the left and right ends of the lower collar portion 11c.

The iron core 13 is formed in a columnar shape, and has a rectangular plate-shaped head portion 13 a whose left-right dimension is longer than the outer diameter of the iron core 13 at the lower end.

As shown in FIGS. 1 and 2, the yoke 7 is formed by bending a rectangular plate at a right angle about the center in the front-rear direction and extending downward from the horizontal portion 7a parallel to the horizontal plane and the rear end portion of the horizontal portion 7a. And a magnetic path for magnetic flux is formed around the coil 12. The horizontal portion 7a is inserted into the upper flange portion 11b of the bobbin 11 from the rear opening, and is fitted into a recess formed by the upper surface of the trunk portion 11a and the upper flange portion 11b. Further, a through hole 7c penetrates the lateral portion 7a, and the central axis of the through hole 7c is made equal to the central axis of the through hole 11d during the fitting. And the through hole 11d
The upper end portion of the iron core 13 projecting upward from the base 7 is caulked and fixed to the through hole 7c, whereby the yoke 7
Is connected to the iron core 13. On the other hand, at the lower end portion of the iron core 13, the head 13 a is in contact with the lower surface of the lower collar portion 11 c, so that the yoke 7 and the iron core 13 do not fall out of the bobbin 11. The upright part 7b is spaced apart from the coil 12 and arranged in parallel with the central axis of the iron core 13, and three protrusions (not shown) protruding rearward are provided on the rear surface.

As shown in FIGS. 1 and 2, the actuating spring piece 8 is formed by bending a conductive thin plate such as a copper plate into a substantially L shape, and is parallel to a normal direction of the horizontal plane and an operating portion 8a parallel to the horizontal plane. The fixed portion 8b is configured by a hinge spring portion 8c which is a bent portion between the operating portion 8a and the fixed portion 8b. Actuator 8
a is extended in the forward direction, and the armature 9 is fixed by caulking near the rear of the upper surface of the operating portion 8a. At the front end of the operating portion 8a, a hole that penetrates in the vertical direction is formed,
A movable contact 10 formed in a substantially spherical shape is fixed by caulking in the hole, and the movable contact 10
The top portions in the vertical direction are respectively opposed to fixed contacts 16a and 17a described later. And the fixing | fixed part 8b is provided with the three hole parts 8e penetrated in the front-back direction, and is fixed to the rear surface of the standing part 7b of the yoke 7 with the terminal board 20 mentioned later. At this time, the front part of the operation part 8a is inserted from the rear side opening of the cylinder part of the lower collar part 11c.

The terminal plate 20 serves as a common terminal that is electrically connected to the movable contact 10 via the operating spring piece 8. As shown in FIG. 2, the terminal plate 20 is formed by punching a conductive plate material and bending it so that the U-shaped main body portion 20a and the pair of L-shaped terminal pieces 20b are integrated. Formed. The main body 20a is provided with three holes 20c that penetrate in the front-rear direction. The main body portion 20a has three protrusions (not shown) of the upright portion 7b as holes 8e, 2e.
By caulking to 0c, it is fixed to the rear surface of the standing portion 7b together with the fixing portion 8b.

As shown in FIGS. 1 and 2, the armature 9 is formed in a substantially rectangular plate shape with a magnetic material, and is fixed to the rear side of the upper surface of the operating portion 8a as described above. Also, the rear end 9 of the armature 9
As shown in FIG. 1, a is in contact with the lower end portion 7d of the upright portion 7b of the yoke 7 in the left-right direction.

That is, the yoke 7 supports the armature 9 via the operating spring piece 8 so as to be swingable in the vertical direction. The electromagnet 6, the yoke 7, the actuating spring piece 8, the armature 9 and the movable contact 10 constituting the electromagnetic block 1 cooperate with each other to form a magnetic circuit by the coil 12.

As shown in FIG. 2, the fixed contact portion 15 includes a normally open (NO) fixed contact terminal plate 16 having a fixed contact 16 a facing the movable contact 10 on the upper surface side of the movable spring piece 8, and the movable spring piece 8. Normally closed (NC) having a fixed contact 17a facing the movable contact 10 on the lower surface side
It consists of a fixed contact terminal plate 17.

The NO fixed contact terminal plate 16 is formed in a convex shape by a conductive material, and further, the right end portion extends downward, and is formed in a substantially L shape as a whole. A fixed contact 16a formed in a substantially hemispherical shape is disposed at the center of the lower surface of the convex portion. Protruding pieces 16b are provided on the front left and right sides of the convex portion. The left and right protruding pieces 16b are respectively fitted into a pair of recesses 11e provided on the left and right front upper ends of the lower flange portion 11c, so that the NO fixed contact terminal plate 1
6 is fixed to the bobbin 11. A terminal piece 16c extending downward is provided at the end of the right protruding piece 16b.

The NC fixed contact terminal plate 17 is formed in a convex shape by a conductive material, and further, a conductive terminal piece 17c protruding downward in a rectangular plate shape is provided at the left end portion. A fixed contact 17a formed in a substantially hemispherical shape is disposed at the center of the upper surface of the convex portion. The protrusions 17b provided on the front left and right sides of the convex-shaped part are respectively fitted to the pair of recesses 11e provided on the front lower left and right of the lower collar part 11c, so that the NC fixed contact terminal plate 17 is Bobbin 1
1 is fixed.

In the first embodiment, the movable contact 10 is applied to a contact switching type c contact that makes contact with the two fixed contacts 16a and 17a. Not limited to this, the present invention can also be applied to a normally open type a contact and a normally closed type b contact that perform contact / separation operation with respect to one fixed contact.

When the electromagnetic block 1 is housed in the case 2, first, as shown in FIG.
11 g and the pair of terminal pieces 20 b are inserted into the insertion holes 5 a, the terminal pieces 16 c and 17 c are inserted into the insertion portions 5 b, and each terminal piece protrudes downward from the bottom wall of the base 5, so that the electromagnetic block 1 is formed on the inner bottom surface of the base 5. Place. Next, the body 4 is covered from above the base 5. At this time, the front upper end of the lower collar portion 11c of the bobbin 11 is disposed on the side of the recessed portion 4a, and the locking step portion 4b of the body 4 is
It is placed on the upper end of the side wall of the base 5 over the entire circumference. Then, the body 4 lower surface opening periphery and the lower surface of the base 5 bottom wall are assembled by sealing with a sealing material 2a such as a thermosetting resin (for example, epoxy resin). The electromagnetic switching device of the first embodiment is mounted on the printed wiring board 3 by inserting five terminal pieces excluding the terminal piece 17c protruding from the lower surface of the bottom wall of the base 5 into the through hole 3a and soldering them. The

  Next, the basic operation of the electromagnetic switching device described above will be described.

When no current flows through the coil 12, the electromagnet 6 is in a non-excited state, and the armature 9 is located away from the head 13 a of the iron core 13. That is, the contact with which the movable contact 10 contacts is the fixed contact 17a.

When a current flows through the coil 12 from this state, the electromagnet 6 is excited, and the armature 9
Due to this suction force, the rear end portion 9a is displaced upward with the back end portion 9a as a fulcrum against the elastic return force of the operating spring piece 8, and is attracted to the head portion 13a of the iron core 13. With this suction operation, the movable contact 10 is displaced upward together with the armature 9 via the operating portion 8 a of the operating spring piece 8. That is, movable contact 1
The contact point where 0 comes in contact is switched from the fixed contact point 17a to the fixed contact point 16a.

Thereafter, when the current flowing through the coil 12 is cut off, the electromagnet 6 is demagnetized, and the attractive force of the electromagnet 6 disappears. Therefore, the armature 9 is moved downward by the elastic return force of the operating spring piece 8 in the downward direction opposite to the attracting direction. Displaces and moves away from the head 13 a of the iron core 13. With this separation operation, the movable contact 10 is displaced downward together with the armature 9 via the operating portion 8 a of the operating spring piece 8.
That is, the contact with which the movable contact 10 contacts is switched from the fixed contact 16 to the fixed contact 17a.

By repeating the excitation and demagnetization of the electromagnet 6 in this manner, the contact is separated from the fixed contacts 16a and 17a opposed to the movable contact 10 to switch the contacts.

  Next, the gist of the present invention will be described.

Case 2 of Embodiment 1 is a material with high thermal conductivity (for example, a liquid crystal polymer containing a special filler).
Formed by. Further, on the inner wall surface of the upper end portion of the body 4 facing the connecting portion between the iron core 13 and the yoke 7, as shown in FIG. 1, there is a convex portion 2 b that protrudes downward over substantially the entire surface except the left and right front and rear ends. The convex portion 2 b is in contact with the upper surface of the electromagnetic block 1, that is, the upper surface of the iron core 13 and the upper surface of the yoke 7. That is, the heat generated in the electromagnetic block 1 is conducted upward and easily radiated from the body 4 of the case 2 to the outside via the convex portion 2b. Therefore, the electromagnetic switching device according to the first embodiment can easily enhance the heat dissipation effect to the outside and suppress the increase in the internal temperature without newly increasing the number of members. Moreover, since the electromagnetic block 1 is in contact with the case 2 farthest from the base 5 facing the printed wiring board 3, heat conduction to the solder joint portion can be suppressed and joint failure can be prevented. In addition to the case 2 described above, the upper collar portion 11b of the bobbin 11
If it is formed of the same high thermal conductive material, the heat dissipation effect can be further enhanced.

By the way, in this Embodiment 1, the convex part 2b provided in the inner wall surface of the upper end part of the body 4 is contact | abutting on the upper surface of the electromagnetic block 1. FIG. However, the present invention is not limited to this, and the inner wall surface of the upper end portion of the body 4 may be brought into direct contact with the upper surface of the electromagnetic block 1 by shortening the vertical dimension of the body 4 instead of providing the convex portion 2b.

Moreover, as shown in FIG. 4, you may interpose the high heat conductive sheet 30 (for example, graphite sheet) between the mutual contact surfaces of the electromagnetic block 1 and the inner wall of the upper end of the body 4. With this high heat conductive sheet 30, the amount of heat transferred from the upper surface of the yoke 7 to the inner wall of the upper end of the body 4 is increased, and the heat dissipation effect can be further enhanced.

(Embodiment 2)
Hereinafter, Embodiment 2 of the present invention will be described with reference to FIG. In the second embodiment,
Since the basic configuration is the same as that of the first embodiment, common components are denoted by the same reference numerals and description thereof is omitted.

In the first embodiment, the upper surface of the iron core 13 and the upper surface of the yoke 7 are brought into contact with the inner wall surface of the upper end portion of the body 4. The second embodiment is characterized in that the heat dissipating piece 8d of the operating spring piece 8 is brought into contact with the inner wall surface of the upper end portion of the body 4.

Among the members constituting the electromagnetic block 1, the member having a high calorific value is the operating spring piece 8 serving as an energization path. Therefore, the upper end portion of the operating spring piece 8 is provided with a heat radiating piece 8d extending upward from the upper end portion of the fixed portion 8b and further extending forward along the inner wall surface of the upper end portion of the body 4. The operating spring piece 8 is directly brought into contact with the inner wall surface of the upper end portion of the body 4 via Therefore, the heat generated from the actuating spring piece 8 is efficiently conducted directly to the case 2 via the heat radiating piece 8d,
The heat dissipation effect can be further enhanced. In addition, since heat conductivity becomes high, so that the purity of copper is high,
The operating spring piece 8 including the heat radiating piece 8d is preferably formed of, for example, a copper alloy used for the material of the lead frame.

It is sectional drawing of Embodiment 1 of this invention. It is a disassembled perspective view in the same as the above. The case in the above is shown, (a) is an upper perspective view, (b) is a lower perspective view. It is principal part sectional drawing when the high heat conductive sheet in the same as above is interposed. It is principal part sectional drawing of Embodiment 2 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electromagnetic block 2 Case 6 Electromagnet 7 Relay 8 Actuating spring piece 9 Armature 10 Movable contact 11 Bobbin 12 Coil 13 Iron core 16a Fixed contact 17a Fixed contact

Claims (3)

A movable contact that is displaced integrally with the armature is installed opposite to the movable contact by attracting and separating the armature from the iron core by the attractive force of the electromagnet and the elastic return force of the operating spring piece. In the electromagnetic switching device that contacts and separates from a fixed contact, the electromagnetic block including the electromagnet, the yoke, the operating spring piece, the armature, the movable contact, and the bobbin is housed. The electromagnet includes an exciting coil wound around the bobbin and the iron core disposed through the bobbin, and the yoke is formed of the iron core. The armature is connected to one end, and the armature is swingably supported through the operating spring piece, and the case is formed of a special filler-containing liquid crystal polymer that is a resin member having high thermal conductivity, and the iron core and the Pair with connecting part with yoke An inner wall surface of the case for an electromagnetic switching device, characterized in that in contact with the at least part of the electromagnetic block. 2. The electromagnetic sheet according to claim 1 , wherein a graphite sheet, which is a highly heat conductive sheet , is interposed between a part of the electromagnetic block and an inner surface of the case. Switchgear. 2. A heat radiating piece extends along the inner wall surface at an end of the operating spring piece coupled to the yoke, and the heat radiating piece contacts the inner wall surface. The electromagnetic switchgear according to 2.

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