JP4000553B2 - Electromagnetic relay - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a seal-type electromagnetic relay in which an opening side of a case is sealed with a sealing material and airtightness inside and outside the case is maintained.
[0002]
[Prior art]
In general, small electromagnetic relays mounted on in-vehicle circuit boards, etc. are sealed so that they can withstand washing after mounting the board and to ensure the prescribed waterproof and dustproof properties. Type relays (ie, seal-type relays) have become mainstream.
In this sealed relay, a relay body made up of an electromagnet (coil and iron core), a contact or a conductive terminal is covered with a case having a square section with one end opened, and the opening side of the case is closed with a closing member. And a gap between the joint portions of the case are sealed with a sealing material (for example, an adhesive such as an epoxy resin). As the closing member, one flange of a spool around which the coil is wound may be used as the closing member, or a separate member (for example, a member called a base member) is used as the closing member. It may be provided as.
By the way, in such a type of relay, in order to ensure its sealing performance at high temperatures and to prevent the case from bulging (bending of the case), the adhesive surface (joint surface) between the case and the closing member is widened, A device has been devised such as increasing the thickness of the case or partially forming reinforcing ribs on the inner surface of the case. Without such ingenuity, the air inside the relay sealed due to the high temperature during soldering of the relay terminal and the board (about 260 ° C in the surface mount type) would expand, causing the case to bend and adhesive. The joint portion that has been hardened and hardly bent is easily peeled off. For example, Japanese Utility Model Laid-Open No. 5-69846 (utility model registration publication No. 2594726) and Japanese Utility Model Laid-Open No. 63-56546 disclose protrusions (partition walls 6c, guide protrusions 5a, An electromagnetic relay forming 5b) is disclosed.
[0003]
[Problems to be solved by the invention]
However, the conventional seal-type relay cannot sufficiently satisfy both the demand for downsizing and the demand for high heat resistance, both of which have recently become stronger.
This is because, for example, the method of simply increasing the thickness of the side wall of the case or simply forming the above-mentioned reinforcing ribs on the inner surface of the case to prevent deflection at high temperatures increases the external dimensions and reduces the size. This is because there is a problem in that the effective internal volume of the case is reduced and the performance of the relay is reduced. Note that the reduction of the effective internal volume of the case means that the dimensions of the components constituting the relay body are forcibly reduced. For example, the attractive force of the electromagnet is reduced due to the reduction of the coil, yoke or iron core. In addition, the current capacity is reduced due to the smaller conductive terminal.
In addition, the method of simply enlarging the joint surface of the case and the closure member to prevent deflection at high temperatures also increases the outer dimension of the case (ie, the outer dimension of the relay) or the effective inner volume of the case (relay This is because the component dimensions of the main body are reduced, and there are similar problems.
Accordingly, an object of the present invention is to provide a highly heat-resistant sealed relay that is small in size and can maintain its sealing performance even at high temperatures.
[0004]
[Means for Solving the Problems]
The electromagnetic relay according to the present invention is covered with a case having a rectangular cross section with an open lower end side , one flange of a spool around which an electromagnet coil is wound is disposed on the lower end opening side of the case, and the other flange of the spool There are disposed on the upper end back side of the case, in the electromagnetic relay the lower end opening side of the case is sealed by being closed by the closing member sealing material,
The reinforcing rib of the case protrudes inward from the inner surface of the case so as to be disposed in an empty space formed between the roundness of the corner of the coil wound around the spool and the inner surface of the case. forming manner, the lower end surface of the reinforcing rib is joined to the upper surface of the closure member, is the joint which is characterized in that fixed in the sealing material.
[0005]
In the electromagnetic relay according to the present invention, the reinforcing ribs of the case are arranged in the empty space formed between the roundness of the corners of the coil and the inner surface of the case. For this reason, although the case is provided with reinforcing ribs for the case, the outer dimension of the case (that is, the outer dimension of the relay) increases correspondingly, and the effective inner volume of the case (part dimensions of the relay body) decreases. There will be no negative effects.
Moreover, the lower end of the reinforcing rib of the case was bonded to the upper surface of the closing member, and this bonded portion was also fixed with a sealing material. For this reason, when the case is about to expand outward due to an increase in the internal pressure of the case at high temperatures, a force in the direction in which shearing stress is generated is also applied to the sealing material, and the strength against peeling of the sealing material is increased. Greatly improved.
Therefore, it is possible to sufficiently satisfy both the demand for downsizing and the demand for high heat resistance, both of which have become stronger recently. That is, ensuring the sealing performance at high temperatures, and preventing the swelling of the case (bending of the case) and peeling of the joint between the case and the closing member (that is, improvement of peeling strength, etc.) can reduce the size of the relay. This can be realized without hindering high performance.
[0006]
In a preferred aspect of the present invention, a recess that facilitates the flow of the sealing material is formed at a position corresponding to the reinforcing rib on the side surface of the closing member.
In this case, there is an advantage that the filling of the sealing material (in particular, filling of the joint portion of the reinforcing rib and the closing member) is easy and reliable, and the relay is also excellent in terms of productivity.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an example of an embodiment when the present invention is applied to a small electromagnetic relay will be described with reference to the drawings.
FIG. 1 is a side view of the electromagnetic relay 1 of this example (a view of the case and the like viewed from the side), and FIG. 2 is an enlarged view of a portion indicated by a symbol X in FIG. FIG. 3 is a perspective view of the electromagnetic relay 1 (a state before attaching the case), and FIG. 4 is a front view of the electromagnetic relay 1 (a view of the case and the like seen from the front). 5A to 5C are a side sectional view, a perspective view, and a horizontal sectional view, respectively, of the case 14 described later. FIG. 6 is an exploded perspective view of the electromagnetic relay 1 (a state before attaching a case or the like), and FIG. 7 is a horizontal sectional view of the electromagnetic relay 1 (a state before attaching the case). In FIG. 4, the sealing material is not shown. In the following, the side where the case 14 is opened (the lower side in FIG. 4 and the like) is referred to as the case opening side, the lower end side or the lower side, and the opposite side (the upper side in FIG. 4 and the like) is the rear side of the case. It is called the upper end side or the upper side.
[0008]
As shown in FIG. 4, the electromagnetic relay 1 includes a spool 2 for winding a coil 2c (shown in FIG. 3 and the like) constituting an electromagnet, an iron core 3 of an electromagnet attached to the spool 2 in an inserted state, An L-shaped yoke 4 that is connected to the lower end of the iron core 3 and serves as a path for magnetic lines of force, and a movable base whose upper end side is joined to the upper end side of the yoke 4 and attracted to the iron core 3 when the coil is energized to swing the front end side. A leaf spring in which the iron piece 5 and the upper plate-like portion 6a are swingable, and the plate-like portion 6a is attached to the upper surface side of the movable iron piece 5, and the movable contact spring. A movable contact 7 attached by crimping to the tip of the plate-like portion 6a, a first fixed contact 8 (NC contact) to which the movable contact 7 is pressed when the coil is not energized, and the first fixed contact 8 at the upper end. First fixing attached by caulking A second fixed contact 10 (NO contact) to which the movable contact 7 is pressed when the coil is energized, a second fixed terminal 11 to which the second fixed contact 10 is attached to the upper end portion by caulking, and each coil A first coil terminal 12 and a second coil terminal 13 connected to the wires, respectively, and a case 14 having a lower end opened.
[0009]
The electromagnetic relay 1 is of a type in which the lower flange 2b of the spool 2 in FIG. 4 also serves as a so-called base for miniaturization, and each part except the case 14 is centered on the spool 2. The case 14 is finally covered with the sub-assembly thus assembled, and then the opening side of the case 14 is sealed with a sealing material 20 such as a thermosetting resin (for example, epoxy resin) (shown in FIG. 1). ) And assembled. The sealing material 20 is filled by dropping a predetermined amount of uncured sealing material 20 into the opening of the case 14 with the opening side of the case 14 facing upward in the vertical direction, and then putting it in a heating tank or the like. This is done by curing the material 20.
Further, the lower plate side of the movable contact spring 6, the first fixed terminal 9, and the second fixed terminal 11 has a base (flange 2 b) as in the first coil terminal 12 and the second coil terminal 13. ) And connecting end portions 21, 22, and 23 for connecting each contact to a predetermined circuit conductor of the substrate. In FIG. 4, the second coil terminal 13 is on the side facing the first coil terminal 12, and the lower end portion of the first fixed terminal 9 (that is, the connection end portion 22) is the lower end portion of the second fixed terminal 11 (that is, the connection end portion 22). , On the opposite side of the connecting end 23).
[0010]
Here, as shown in FIG. 6, the coil terminals 12 and 13, the first fixed terminal 9, and the second fixed terminal 11 are fixed to the flange 2 b of the spool 2 by press-fitting.
As shown in FIG. 5, the case 14 has a rectangular parallelepiped shape with a square section opened at the lower end side, and is made of, for example, a synthetic resin molded product. As shown in FIG. 5, reinforcing ribs 31, 32, 33, and 34 extending in the vertical direction are formed by integral molding at four positions on the inner surface of the case. These reinforcing ribs 31 to 34 are arranged in empty spaces S1 to S4 (shown in FIG. 7) formed between the roundness of the four corners of the coil 2c wound around the spool 2 and the inner surface of the case 14. As such, the formation position is set. Further, as shown in FIG. 5A or 1, the lower ends of the reinforcing ribs 31 to 34 extend to a position where they are joined to the upper surface of the flange 2b that is a closing member, and the gap between the joined portions is a capillary tube. Due to the phenomenon and gravity, the seal material 20 is sufficiently large to flow in as shown in FIG. Further, the upper ends of the reinforcing ribs 31 to 34 extend to the inner surface (ceiling surface) of the upper wall of the case 14 as shown in FIG. In addition, what is shown with the code | symbol 14a in FIG. 5 is the convex part of the case 14 provided in the seal part of the movable contact spring 6 (end part 21 for connection) (refer FIG. 4).
[0011]
The spool 2 has an upper end flange 2a disposed on the back side of the case and a lower end flange 2b disposed on the opening side of the case 14, and the above-described reinforcing ribs 31 to 34 of the upper end flange 2a. Relief portions 35 to 38 (concave portions) for avoiding interference with the reinforcing ribs 31 to 34 are formed at positions corresponding to (see FIG. 6). Further, in the side surface of the flange 2b on the lower end side of the spool 2 (joint surface with the case), the concave portions 39 and 40 for facilitating the flow of the sealing material 20 into the positions corresponding to the reinforcing ribs 31 and 32 described above. (See FIG. 1 or FIG. 3).
[0012]
As described above, the seal-type relay of this example described above is in the empty spaces S1 to S4 (shown in FIG. 7) formed between the roundness of the four corners of the coil 2c and the inner surface of the case 14. The reinforcing ribs 31 to 34 of the case 14 are arranged. For this reason, although it is the structure provided with the reinforcement ribs 31-34, the external dimension (namely, external dimension of the relay 1) of the case 14 becomes large correspondingly, or the effective internal volume of the case 14 (component of a relay main body) There is no adverse effect that the dimension) becomes small.
Further, the lower ends of the reinforcing ribs 31 to 34 were joined to the upper surface of the closing member (in this case, the flange 2 b), and this joined portion was also fixed by the sealing material 20. For this reason, when the case is about to expand outward due to an increase in the internal pressure of the case at a high temperature, a force in a direction in which a shear stress is generated is applied to the sealing material 20 that fixes the joint. The strength against peeling of the sealing material 20 is remarkably improved. Incidentally, for example, in a configuration in which the sealing material 20 is merely filled in the gap between the inner side surface of the case 14 and the side end surface of the flange 2b, the peeling direction in which the case 14 tends to bulge outward at high temperatures (FIG. 1). In the right and left direction), the bonding is only between the planes perpendicular to the surface (only the bonding in the direction in which the tensile stress acts on the sealing material 20), and the strength of the sealing material 20 that is relatively strong against the shear stress cannot be utilized. Become. However, in the configuration of this example, the joint between the lower ends of the reinforcing ribs 31 to 34 and the upper surface of the flange 2b is also fixed by the sealing material 20 as shown in FIG. Since it becomes the working direction, the bulging and peeling of the case 14 are more firmly prevented by the fixing force of this portion.
[0013]
Therefore, it is possible to sufficiently satisfy both the demand for downsizing and the demand for high heat resistance, both of which have become stronger recently. That is, the sealing performance is ensured at a high temperature, and the case bulge (case deflection) and the joint between the case and the closing member (in this case, the spool flange) are prevented from peeling (that is, the peel strength is improved, etc.) ), However, can be realized without hindering the miniaturization and high performance of the relay.
Particularly in the case of this example, since the reinforcing ribs 31 to 34 are provided in the longitudinal direction (in this case, the vertical direction) on the side surface of the case 14, the effect of preventing the deflection by the reinforcing ribs 31 to 34 is exhibited more highly. Can contribute by increasing heat resistance.
Moreover, in this example, the recessed parts 39 and 40 for making it easy to flow the sealing material 20 into the position of the reinforcement ribs 31 and 32 are formed in the side surface of the flange 2b. For this reason, there is an advantage that the filling of the sealing material 20 (particularly, the filling of the joint between the reinforcing ribs 31 and 32 and the flange 2b) is easy and reliable, and the relay is also excellent in terms of productivity.
[0014]
In addition, this invention is not restricted to the aspect of embodiment described above.
For example, the above-described recesses 39 and 40 are not necessarily required. In the above-described embodiment, the same recesses as those of the recesses 39 and 40 may be provided for the reinforcing ribs 33 and 34 .
Further, the closing member of the present invention may be constituted by a member separate from the spool.
Moreover, although the said example is an example which applied this invention to the electromagnetic relay of what is called a c contact type (the type which has both a contact and b contact), b which has only a contact type and b contact which has only a contact. Needless to say, the same applies to the contact type.
FIG. 2B shows a joint structure of a case reinforcing rib and a closing member, which is an example of development from the present invention. This is because the lower end of the reinforcing rib 32 extends to the vicinity of the opening side end surface of the case 14, and the position corresponding to the reinforcing rib 32 on the side end surface of the flange 2 b is formed into a concave shape corresponding to the outer shape of the reinforcing rib 32. In this structure, the extending portions of the reinforcing ribs 32 are joined so as to be inserted in a state where the reinforcing ribs 32 are vertically penetrated, and the sealing material 20 is filled in the gaps of the joining portions as shown in FIG.
[0015]
【The invention's effect】
In the electromagnetic relay according to the present invention, the reinforcing ribs of the case are arranged in the empty space formed between the roundness of the corners of the coil and the inner surface of the case. For this reason, although the case is provided with reinforcing ribs for the case, the outer dimension of the case (that is, the outer dimension of the relay) increases correspondingly, and the effective inner volume of the case (part dimensions of the relay body) decreases. There will be no negative effects.
Moreover, the lower end of the reinforcing rib of the case was bonded to the upper surface of the closing member, and this bonded portion was also fixed with a sealing material. For this reason, when the case is about to expand outward due to an increase in the internal pressure of the case at high temperatures, a force in the direction in which shearing stress is generated is also applied to the sealing material, and the strength against peeling of the sealing material is increased. Greatly improved.
Therefore, it is possible to sufficiently satisfy both the demand for downsizing and the demand for high heat resistance, both of which have become stronger recently. That is, ensuring the sealing performance at high temperatures, and preventing the swelling of the case (bending of the case) and peeling of the joint between the case and the closing member (that is, improvement of peeling strength, etc.) can reduce the size of the relay. This can be realized without hindering high performance.
[Brief description of the drawings]
FIG. 1 is a side sectional view of an electromagnetic relay.
FIG. 2 is an enlarged view of a portion X in FIG.
FIG. 3 is a perspective view of an electromagnetic relay.
FIG. 4 is a front view of the electromagnetic relay.
FIG. 5 is a diagram showing a case of an electromagnetic relay.
FIG. 6 is an exploded perspective view of the electromagnetic relay.
FIG. 7 is a horizontal sectional view of the electromagnetic relay.
[Explanation of symbols]
1 Electromagnetic relay 2 Spool 2a Flange (the other flange)
2b Flange (One flange, closing member)
3 Iron core 4 Yoke 5 Movable iron piece 6 Movable contact spring (movable contact terminal)
7 movable contact 8 first fixed contact 9 first fixed terminal 10 second fixed contact 11 second fixed terminal 12 first coil terminal 13 second coil terminal 14 case 20 sealing material 31-34 reinforcing ribs 39, 40 recess

Claims (2)

One flange of a spool, which is covered with a case having a rectangular cross section with an open lower end side and around which an electromagnet coil is wound, is disposed on the lower end opening side of the case, and the other flange of the spool is on the back side of the upper end of the case In the electromagnetic relay that is disposed in the lower end opening side of the case is closed with a closing member and sealed with a sealing material,
The reinforcing rib of the case protrudes inward from the inner surface of the case so as to be disposed in an empty space formed between the roundness of the corner of the coil wound around the spool and the inner surface of the case. formed as the electromagnetic relay of the lower end surface of the reinforcing rib is joined to the upper surface of the closure member, characterized in that the joining portion is fixed with the sealing material.   2. The electromagnetic relay according to claim 1, wherein a recess for facilitating the flow of the sealing material is formed on a side surface of the closing member at a position corresponding to the reinforcing rib.

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