WO2015045515A1

WO2015045515A1 - Structure for connecting terminal of electrical component

Info

Publication number: WO2015045515A1
Application number: PCT/JP2014/066125
Authority: WO
Inventors: 哲弥西村
Original assignee: 日本サーモスタット株式会社
Priority date: 2013-09-25
Filing date: 2014-06-18
Publication date: 2015-04-02
Also published as: JP2015065019A

Abstract

The present invention is configured such that, when a connection is to be established between a first terminal (6) comprising a high-melting metal and a second terminal (4) comprising a low-melting metal and having a molded resin member (3) attached to the side opposite the joining surface thereof, the first terminal (6) is coupled in a non-contact state with the connection surface of the second terminal (4) across a prescribed gap, and a laser beam is directed from the side of the first terminal (6) opposite the joining surface to melt the first terminal (6) under heating, causing the joining surface of the second terminal (4) to also melt due to heat conducted from the first terminal (6), thereby welding together both terminals.

Description

Terminal connection structure for electrical components

The present invention relates to a terminal connection structure for an electrical component suitable for use in the case where one terminal is resin-molded when welding a terminal made of a different metal.

For example, in a thermostat device used for controlling the flow rate of cooling water in an internal combustion engine, a heater is incorporated to operate the on-off valve of the device regardless of the cooling water temperature, and the heater is installed as necessary. It is generally employed to control opening and closing of the on-off valve by controlling energization.

Conventionally, this type of electric control type thermostat has a thermoelement enclosing wax or the like so as to face the inside of a device housing that forms a cooling water passage as shown in Patent Document 1, for example, and heat is generated depending on the cooling water temperature. The movement of the axis direction of expansion and contraction is transmitted to the valve body that opens and closes the cooling water passage, thereby controlling the opening and closing of the cooling water passage. Then, a rod-shaped heater is exposed from the outside of the device housing into the thermo element, and the wax can be selectively thermally expanded by the heat effect of the rod-shaped heater.

By the way, in this type of electric control type thermostat, terminal terminals for external connection for connecting the heater to the outside of the apparatus are drawn out of the apparatus housing. That is, the terminal terminal has a resin-molded connector member for fixing the terminal terminal to the apparatus housing side. The connector member is configured such that a part of the connector terminal is exposed to the outside, and the heater terminal on the heater side is connected to the connector terminal.

Here, the above-described heater terminal is generally made of a high-melting point metal such as nickel or kovar, and the connector terminal is made of a low-melting point metal such as brass. These terminals are welded, for example, by resistance welding. Has been.

However, in such resistance welding, it is necessary to weld both terminals to be welded by sandwiching them between the electrodes, and a space for arranging the above electrodes must be provided at the joint between both terminals. I must. Therefore, the structure of the joint portion of both terminals tends to be complicated, and the joint portion has to be enlarged including a space, so that there is a problem that the connector member becomes large.

Of course, in welding with the resin mold type terminal as described above, it is conceivable to make a hole in a predetermined portion of the resin member, insert an electrode into the hole, and perform welding. However, if it does in this way, it will be necessary to block a hole in a post process, and there will also be a problem that the number of parts will increase, parts cost and assembly cost will increase, and cost will increase.

For example, in Patent Document 2, in a joint in which a gap is provided between an upper member having a high melting point and a lower member having a low melting point, only the upper member is heated and melted by laser irradiation, and heat transfer from the upper member is performed with the lower member. A laser bonding method for melting the bonding surface is disclosed.

Japanese Patent Laid-Open No. 2005-155831 JP 2004-042053 A

However, in the laser joining method in Patent Document 2 described above, the upper member to be joined and the lower member are in a non-contact state with a predetermined gap between them and laser irradiation is performed from one member side. Thus, both members are simply welded together.
And in this patent document 2, there is no description which suggests about joining in case one member mentioned above is resin modal molding.

In particular, in the electric control type thermostat as in Patent Document 1 described above, it is desirable to join the connector terminal and the heater terminal on the heater side in the connector portion of the terminal terminal for external connection. It arrange | positions in the connector member molded by resin molding. In particular, when it is desired to reduce the size of the connector part, the connector part is often embedded in a state where a part is exposed in the resin member constituting the connector member.

Therefore, in the case where the connector terminal and the heater terminal embedded in the resin mold are welded and joined as described above, it is desirable to take care that the resin member is not affected by the welding heat.

This invention is made | formed in view of such a situation, and the 2nd terminal in the molded resin member and the 1st terminal joined to this can be weld-joined simply and reliably. Further, it is an object of the present invention to obtain a terminal connection structure for an electrical component that can be configured in a small and compact manner and that is low in cost.

In order to meet such an object, the terminal connection structure for an electrical component according to the present invention (the invention described in claim 1) includes a first terminal made of a refractory metal and a second terminal made of a low melting metal. In the terminal connection structure of the electrical component to be connected, a molded resin member is attached to the anti-joining surface of the second terminal, and the first terminal is on the connection surface of the second terminal. A non-contact body is contacted with a predetermined gap, laser irradiation is performed from the anti-joint surface side of the first terminal, the first terminal is heated and melted, and heat is transferred from the first terminal. It is characterized in that both terminals are welded together by melting the joint surface of the second terminal.

The terminal connection structure for electrical parts according to the present invention (the invention according to claim 2) is the electrical component terminal connection structure according to claim 1, wherein the first terminal is melted and melted by heating and melting by laser irradiation from the anti-joint surface side. Both terminals are joined by joining the first terminal to the joint surface of the second terminal by its own weight.

The terminal connection structure for an electrical component according to the present invention (the invention described in claim 3) is the electrical component type thermostat according to claim 1 or 2, wherein the first component is a heater of a heater in the thermostat. The second terminal is a connector terminal in a connector for externally connecting the heater.

Here, the first terminal made of a refractory metal is made of, for example, nickel, cobalt, an alloy thereof, or the like. The second terminal made of a low melting point metal is made of, for example, brass. Of course, the expressions high melting point and low melting point are relative expressions of the melting points of the two metal materials to be joined, and do not specify a certain temperature range. Further, the metal material is not limited to the above example.

In particular, according to the present invention, the resin member by molding is attached to the antibonding surface side of the second terminal, and a part of the resin member surrounds the periphery of the bonding surface of the second terminal. Even when the wall portion is formed, the first terminal is brought into contact with the second terminal in a non-contact state, and laser irradiation is performed from the anti-joint surface side of the first terminal. By doing. Both terminals can be welded together.

Further, when the present invention is applied to a connector portion for energizing a heater for wax heating control in an electric control type thermostat used in an internal combustion engine, a heater terminal made of a high melting point metal and a heater terminal made of a low melting point metal When the connector-side terminal molded with resin so that the resin member exists on the opposite surface in contact with the heat is melted by laser irradiation only on the heater terminal side, and heat transfer from the heater terminal Both terminals can be welded together by melting the joint surface.

Here, both terminals are in a non-contact state, but the molten heater terminal comes into contact with the connector terminal by its own weight and is joined. Further, the laser irradiation only needs to be such that only the heater terminal can be heated and melted, and there is no limitation on just focus or defocus. Further, the intensity and time of laser irradiation may be appropriately selected depending on the properties of the target metal.

As described above, according to the terminal connection structure for an electrical component according to the present invention, the first and second terminals made of different metals are brought into a non-contact state with a predetermined interval from the anti-joint surface side of the first terminal. By performing laser irradiation, the first terminal is melted, and the second terminal is melted by heat transfer from the first terminal, so that both terminals are heated and melted and welded. In spite of the simple configuration, there are various excellent effects listed below.

1. By irradiating only the first terminal (heater terminal) with laser, the first terminal (heater terminal), the second terminal (connector side terminal; hereinafter referred to as connector terminal) are attached to this. Even if the resin member is arranged so as to overlap in the laser irradiation direction, the thermal influence on the peripheral member of the irradiated member is small, and the resin member near the lower plate does not deteriorate.
2. Since the sealing property of the product can be maintained, the effect of preventing cooling water leakage can be exhibited.

3. Due to the joining by heat transfer, the terminal evaporates due to melting and the thickness is not reduced. Therefore, a sufficient bonding area can be secured and the bonding strength is improved. In addition, the thermal effect on the peripheral portion to be joined is small, and the thickness of the resin member in the vicinity of the joining surface can be reduced and the weight can be reduced. Even if the resin member is thinned, the through hole is not opened in the resin member, so that it is not affected by outside air. Also, dust does not enter.

4. No processing for joining is required as in spot welding. Even if the heater terminal is joined with another member having a low melting point such as silver wax (700 ° to 900 ° C.), the silver wax does not melt by heat conduction and the heater terminal does not come off from the separate member.

5. Even if both terminals are in a non-contact state, the melted heater terminal comes into contact with the connector-side terminal by its own weight. Since it joins by its own weight, it can provide high quality products.

6. Since both terminals can be melted and welded by laser irradiation from the back side of one terminal, the other terminal is molded and has a wall portion surrounding the terminal, for example, an electrode for spot welding Even in the case where the periphery of the joint is so narrow that it does not enter, welding can be performed easily and reliably.

1 shows an embodiment of an electric component terminal connection structure according to the present invention, and is a cross-sectional view of a main part of an electronically controlled thermostat. FIG. It is a schematic perspective view for demonstrating the connection part of the terminal connector and heater in the A section of FIG. It is a schematic sectional drawing of the connection part of the terminal connector of FIG. 2, and a heater. It is a schematic sectional drawing for demonstrating the terminal connection structure which concerns on this invention.

1 to 4 show an embodiment of an electric component terminal connection structure according to the present invention.
In these drawings, in the present embodiment, the present invention relates to the connector terminal 4 of the connector portion 3 in the terminal terminal 2 for external connection in the electric control type thermostat 1 and the heater for electric temperature control in the thermostat 1 (16 described later). The case where it is applied to the joint portion with the heater terminal 6 in FIG.

Here, the electric control type thermostat 1 to which the present invention is applied has a conventionally well-known configuration as apparent from Patent Document 1 described above, and a detailed description thereof is omitted here.

In FIG. 1, 10 is a device housing assembled to a device body that forms a cooling water passage (not shown), 11 is a main valve body that opens and closes a cooling water passage 12 formed in the

device housing

10, and 13 is A return spring that biases the main valve body 11.
Reference numeral 15 denotes a thermo element in which the main valve body 11 is assembled and fixed in a part of the axial direction, and includes a wax inside and a piston (both not shown) that moves forward and backward in the axial direction by its thermal expansion and contraction. Has been.

Inside the thermo element 15, a rod-like heater 16 extending from a connector mounting portion opened in the axial direction of the apparatus housing 10 is inserted, and by controlling the heat generation temperature of the heater 16, the wax is Regardless of the cooling water temperature, it is configured so that it can expand and contract.

Now, according to the present invention, in connecting the first terminal (heater terminal 6) made of a high melting point metal and the second terminal (connector terminal 4) made of a low melting point metal, FIG. As shown, a molded resin member (connector member 3) is attached to the anti-joining surface of the connector terminal 4, and the heater terminal 6 has a predetermined gap GAP on the connection surface of the connector terminal 4. The contact is made with a non-contact body, and laser irradiation (indicated by an arrow in FIG. 4) is performed from the side opposite to the surface of the heater terminal 6 to heat and melt the heater terminal 6 and to transmit from the heater terminal 6. It is characterized in that both

terminals

4 and 6 are welded and connected by melting the joint surface of the connector terminal 4 with heat.

Here, as described above, the heater terminals 6 are heated and melted by laser irradiation from the side opposite to the joint surface of the heater terminal 6, and the melted and melted heater terminal 6 is joined to the joint surface of the connector terminal 4 by its own weight. 6 are joined. In FIG. 4, the left side shows a state in which a gap GAP is open between the connector terminal 4 and the heater terminal 6 before laser irradiation, and the right side in FIG. 4 shows that the heater terminal 6 is melted by laser irradiation. And the state joined to the connector terminal 4 with dead weight is shown.

The heater terminal 6 made of the above-described refractory metal is made of, for example, nickel, cobalt, or an alloy thereof. The connector terminal 4 made of a low melting point metal is made of, for example, brass. Of course, the expressions high melting point and low melting point are relative expressions of the melting points of the two metal materials to be joined, and do not specify a certain temperature range. Further, the metal material is not limited to the above example.

Further, the connector terminal 4 as described above is generally plated with a plating material such as Sn, Ag, Au or the like for the purpose of preventing oxidative degradation. Regardless of the type of plating or the presence or absence of the plating process, the heater is used. The welding connection with the terminal 6 in a good state is possible.

Further, according to the present embodiment, when applied to the connector portion 3 of the electric control type thermostat 1, the resin member (connector member) by molding is attached to the anti-joining surface side of the connector terminal 4, and this connector In the case where a part of the member 3 has a wall portion 8 formed so as to surround the periphery of the joint surface of the connector terminal 4, as shown in FIG. 2 and FIG. By arranging the connector terminal 4, the heater terminal 6 is brought into contact with the connector terminal 4 in a non-contact state with a predetermined gap, and laser irradiation is performed from the anti-joining surface side of the heater terminal 6. Both

terminals

4 and 6 can be simply and reliably welded together.

Here, although both the

terminals

4 and 6 described above are in a non-contact state, the molten heater terminal 6 comes into contact with the connector terminal 4 by its own weight and is joined. Further, the laser irradiation may be performed to such an extent that only the heater terminal 6 can be heated and melted. In this case, the intensity of laser irradiation, the laser output, the spot diameter, and the time may be appropriately selected depending on the properties, thickness, width, etc. of the target metal. It has been confirmed by experiments that the width of the heater terminal 6 is good within twice the spot diameter.

According to the above configuration, despite the simple configuration, there are various excellent effects described below.
In other words, by irradiating only the heater terminal 6 with the laser, the heater terminal 6, the connector side terminal (hereinafter referred to as the connector terminal 4), and the connector member 3 attached thereto are overlapped in the laser irradiation direction. However, the thermal influence on the peripheral members of the irradiated member is small, and the connector member 3 side located on the lower side does not deteriorate.
Accordingly, since the connector member 3 is not affected by heat such as welding, the sealing performance of the product can be maintained, and therefore, an effect of preventing cooling water leakage can be exhibited.

Also, because of the joining by heat transfer, the

terminals

4 and 6 are very little evaporated by dissolution and the thickness is not reduced. Therefore, a sufficient bonding area can be secured and the bonding strength is improved. In addition, there is no problem that damages the electrical connection such as a short circuit. In addition, the thermal influence on the peripheral portion to be joined is small, and the thickness of the connector member 3 in the vicinity of the joining surface can be reduced and the weight can be reduced. Further, even if the connector member 3 is thinned, there is an advantage that a through hole is not opened in the member, so that it is not affected by outside air and foreign matter such as dust does not enter.

Furthermore, there is no need for joint processing as in spot welding. Even if the heater terminal 6 is joined to another member with a low melting point such as silver wax (700 degrees to 900 degrees), the silver wax is not melted by heat conduction and the heater terminal 6 is not detached from the separate member. .

Even if both

terminals

4 and 6 are in a non-contact state, the melted heater terminal 6 comes into contact with the connector terminal 4 by its own weight, so that a gap is generated between the both

terminals

4 and 6, However, since the molten heater terminal 6 is joined by its own weight, a high-quality product can be provided.

Further, since both

terminals

4 and 6 can be melted and welded by laser irradiation from the back side of one terminal 6, the other terminal 6 is molded and has a wall portion 8 surrounding the periphery of the terminal. Even if it exists, it can weld-join easily and reliably.

Further, according to the structure of the embodiment described above, welding from the open end side surrounded by the wall portion 8 of the connector member 3 (resin member) in which the terminals 4 are molded is possible, and resistance welding as in the related art is possible. Since the arrangement space such as this electrode becomes unnecessary, the overall length can be reduced, and the entire configuration is simplified.

Here, in the above-described embodiment, reference numeral 9 in FIG. 4 is a holding jig for pressing the connector terminal 4 during welding, and can be freely used as necessary.

In addition, this invention is not limited to the structure demonstrated by embodiment mentioned above, and comprises the junction part of the connector terminal 4 of the connector part of the terminal terminal 2 and the heater terminal 6 in the electric control type thermostat 1 as an electrical component. Needless to say, the shape, structure, and the like of each part can be appropriately modified and changed. For example, the electric component to which the present invention can be applied is not limited to the connector portion of the electric control type thermostat 1 described above.

1 Electric control type thermostat 2 Terminal terminal 3 Connector part 4 Connector terminal (connector side terminal)
6 Heater terminal 8 Wall 10 Device housing 11 Main valve body 12 Cooling water passage 13 Return spring 15 Thermo element 16 Heater (bar heater)

Claims

A terminal connection structure for an electrical component that connects a first terminal made of a refractory metal and a second terminal made of a low melting point metal,
The anti-joint surface of the second terminal is provided with a molded resin member,
The first terminal is brought into contact with a non-contact body with a predetermined gap on the connection surface of the second terminal, and laser irradiation is performed from the anti-joint surface side of the first terminal. The terminal is heated and melted, and the joining surface of the second terminal is also melted by heat transfer from the first terminal, whereby both terminals are welded and connected. Component terminal connection structure.
The terminal connection structure for an electrical component according to claim 1,
The first terminal is heated and melted by laser irradiation from the anti-joint surface side, and the melted and melted first terminal is joined to the joint surface of the second terminal by its own weight, so that both terminals are A terminal connection structure for electrical parts, characterized by being joined.
In the terminal connection structure of the electrical component according to claim 1 or 2,
The electrical component is an electrically controlled thermostat;
The first terminal is a heater terminal of a heater in the thermostat;
The terminal connection structure for an electrical component, wherein the second terminal is a connector terminal in a connector for externally connecting the heater.