BOARD MODULE AND ELECTRICAL JUNCTION BOX

An object is to improve heat dissipation performance while reducing a distance between boards when circuits on the boards are electrically connected to each other. The board module includes a first board including a first circuit, and a first connector provided on the first board, and the first connector is connected to a second connector, a through hole is formed in the first board, the first connector includes a connector housing disposed in the through hole and a first terminal, the first terminal includes a first board-side end portion connected to the first circuit, a first terminal portion held by the connector housing, and a heat dissipation portion provided between a first board-side end portion and the first terminal portion and exposed as seen from the opposite side to the second connector with respect to the connector housing.

TECHNICAL FIELD

The present disclosure relates to a board module and an electrical junction box.

BACKGROUND

JP 2009-129858A discloses an inter-board connection structure that electrically connects circuits of a first board and a second board to each other and includes a first female terminal disposed on a surface of the first board that faces the opposite side to the second board, a second female terminal disposed on a surface of the second board that faces the opposite side to the first board, and a male member that has a first male terminal at one end and a second male terminal at the other end. The male member extends through the first board and the second board, and is connected to the first female terminal and the second female terminal.

JP 2019-8872A discloses a connector that connects a board and an external terminal to each other, including a connector terminal portion connected to the board and the external terminal, and a housing portion that holds the connector terminal portion, in which the housing portion is installed on the board while extending through the board and protruding from two sides of the board in a height direction thereof.

Here, when connecting a connector provided on a board to another connector, downsizing of a structure for connection and improvement in heat dissipation performance are required. No consideration is given to heat dissipation performance in Patent Documents 1 and 2.

In view of this, an object of the present disclosure is to improve heat dissipation performance while downsizing a structure for connection when connecting a connector provided on a board to another connector.

SUMMARY

The board module according to the present disclosure is a board module including a first board including a first circuit, and a first connector provided on the first board, wherein the first connector is connected to a second connector, a through hole is formed in the first board, the first connector includes a connector housing disposed in the through hole and a first terminal, and the first terminal includes a first board-side end portion that is electrically and mechanically connected to the first circuit a first terminal portion held by the connector housing, and a heat dissipation portion provided between the first board-side end portion and the first terminal portion and exposed from the connector housing as seen from a side opposite to the second connector.

Advantageous Effects

According to the present disclosure, when connecting a connector provided on a board to another connector, heat dissipation performance can be improved while downsizing a structure for connection.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

First, embodiments of this disclosure will be listed and described below.

A board module according to the present disclosure is as follows.

In a first aspect, a board module including a first board including a first circuit, and a first connector provided on the first board, wherein the first connector is connected to a second connector, a through hole is formed in the first board, the first connector includes a connector housing disposed in the through hole and a first terminal, and the first terminal includes a first board-side end portion that is electrically and mechanically connected to the first circuit a first terminal portion held by the connector housing, and a heat dissipation portion provided between the first board-side end portion and the first terminal portion and exposed from the connector housing as seen from a side opposite to the second connector.

According to this board module, the connector housing is disposed in the through hole formed in the first board, and the first terminal portion is held by the connector housing. As a result of the first connector and the second connector approaching each other, the first terminal portion and the second terminal portion of the second connector are connected to each other. Since the connector housing that holds the first terminal portion is disposed in the through hole, the structure for connection between the first connector and the second connector can be downsized. Also, since the first terminal is provided between the first board-side end portion and the first terminal portion, and includes the heat dissipation portion exposed as seen from the opposite side to the second connector, the heat dissipation performance can be improved.

In a second aspect, in the board module according to the first aspect, a configuration is also possible in which a second connector provided on a second board including a second circuit provided spaced apart from the first board, and the second connector includes a second terminal including a second board side end portion that is electrically and mechanically connected to the second circuit and a second terminal portion connected to the first terminal portion as a result of the first board and the second board approaching each other.

In a third aspect, in the board module according to the second aspect, a configuration is also possible in which the second board side end portion is electrically and mechanically connected to the second circuit on the first board-side with respect to the second board.

In a fourth aspect, in the board module according to any one of the first through the third aspects, a configuration is also possible in which the heat dissipation portion protrudes on an opposite side to the second connector with respect to the connector housing. With this configuration, excellent heat dissipation can be achieved.

In a fifth aspect, in the board module according to any one of the first through the fourth aspects, a configuration is also possible in which the heat dissipation portion is in contact with a heat dissipation promotion member in a heat conductive manner. In this manner, heat in the first terminal can be efficiently dissipated via the heat dissipation promotion member.

In a sixth aspect, in the board module according to any one of the first through the fifth aspects, a configuration is also possible in which a receiving portion that is in contact with the heat dissipation portion from an opposite side to the first connector in a direction in which the first connector and the second connector are connected to each other is further provided. In this manner, when connecting the connectors to each other, a force that acts on the first terminal portion is taken on by the receiving portion.

In a seventh aspect, in the board module according to any one of the first through the sixth aspects, a configuration is also possible in which the first terminal includes a stress absorption portion that can deform more easily than the first terminal portion, between the first board-side end portion and the first terminal portion. In this manner, when connecting the connectors to each other, a force that acts on the first terminal portion is mitigated due to deformation of the stress absorption portion, and thus the force is unlikely to be transferred to the first board-side end portion. Accordingly, the connection state between the first board-side end portion and the first circuit can be maintained.

In an eighth aspect, in the board module according to any one of the first through the seventh aspects, a configuration is also possible in which the first board-side end portion extends in a direction intersecting a direction in which the first connector and the second connector are connected to each other, and the first board-side end portion is electrically and mechanically connected to the first circuit on the second connector side with respect to the first board. When the first connector and the second connector are connected to each other, the first terminal is pressed away from the second connector. When the first board-side end portion that extends in the direction intersecting the connection direction is electrically and mechanically connected to the first circuit on the second connector side with respect to the first board, a force that presses the first terminal is taken on by the first board. In this manner, the connection state between the first board-side end portion and the first circuit can be maintained.

In a ninth aspect, in the board module according to any one of the first through the eighth aspects, a configuration is also possible in which a peg member that is held by the connector housing and in contact with the first board from the second connector side is further provided. In this manner, a force that acts when the first connector and the second connector are connected to each other is taken on by the peg member from the first terminal portion via the connector housing.

An electrical junction box according to the present disclosure is as follows.

In a tenth aspect, a board module according to any one of first through the ninth aspects, and a case that covers the board module. In this manner, in the electrical junction box, when the circuits of the boards are electrically connected to each other, the heat dissipation performance can be improved while reducing the distance between the boards. This contributes to downsizing of the electrical junction box.

A specific example of a board module and an electrical junction box according to the present disclosure will be described below with reference to the drawings. Note that the present disclosure is not limited to these examples, but defined by the claims, and all changes that come within the meaning and scope of equivalency of the claims are intended to be embraced therein.

Hereinafter, a board module and an electrical junction box according to an embodiment will be described.FIG.1is a schematic perspective view showing an electrical junction box10provided with a board module20.FIG.2is a cross-sectional view taken along line II-II inFIG.1.FIG.3is a cross-sectional view showing a state where a connector is being connected.

Overall Configuration

The electrical junction box10is a component that is connected between electrical components to electrically connect the electrical components. For example, the electrical junction box10is disposed on a power supply path between a power supply such as a battery and a load such as a vehicle-mounted electrical component (e.g., lamp or a wiper) in a vehicle. The electrical junction box10may perform power distribution, power on/off, and the like on the power supply path.

The electrical junction box10includes a board module20and a case12.

The case12is a member that covers the board module20. The case12is made of resin or the like, and has a box-like shape that covers the upper side and four peripheral sides of the board module. A bottom opening of the case12may be closed by a heat dissipation promotion member90. In this case, the heat dissipation promotion member90can be exposed to the outside of the case12and easily dissipate heat to the outside. The bottom opening of the case12may be closed by a bottom plate other than the heat dissipation promotion member90.

The board module20includes a first board30, a first connector40, a second board60, and a second connector70.

The first board30includes a first circuit32. The second board60includes a second circuit62. The second board60is parallel with the first board30with an interval therebetween. The first board30is provided with the first connector40, and the second board60is provided with the second connector70. Due to connection between the first connector40and the second connector70, the first circuit32and the second circuit62are electrically connected to each other.

More specifically, a circuit for performing on/off control of a power circuit is formed on each of the first board30and the second board60.

For example, the first board30includes a power circuit, a switching element inserted into an intermediate portion of the power circuit, and a signal circuit that allows signals for performing on/off control of the switching element to flow therethrough. The power circuit is formed by a bus bar formed by a metal plate or the like, for example. The switching element is, for example, a field effect transistor (FET). The signal circuit is a circuit pattern formed by etching a copper foil, for example. The switching element is mounted on the first board30by being soldered to the power circuit and the signal circuit, for example.

For example, the second board60includes a semiconductor chip and a signal circuit. The semiconductor chip is, for example, an IC (Integrated Circuit) on which an electronic circuit for performing the on/off control of a switching element is formed. The signal circuit is a circuit pattern formed by etching a copper foil, for example.

The first circuit32of the first board30and the second circuit62of the second board60are power circuits or signal circuits. For example, the first circuit32is a signal circuit of the first board30, and the second circuit62is signal circuit of the second board60. In this case, as a result of the first circuit32and the second circuit62being connected to each other via the first connector40and the second connector70, the on/off control of the switching element mounted on the first board30can be performed by the semiconductor chip mounted on the second board60.

Examples of the circuits formed on the first board30and the second board60are not limited to the above examples. For example, a configuration is also possible in which a power circuit is formed on both the first board30and the second board60, and the power circuit of the first board30is the first circuit32and the power circuit of the second board60is the second circuit62. In this case, the first connector40and the second connector70may connect the power circuit formed on the first board30and the power circuit formed on the second board60to each other. The first board30may be a board including a circuit other than the first circuit32, such as a double-sided circuit board or a multi-layer circuit board. Similarly, the second board60may be a board including a circuit other than the second circuit62, such as a double-sided circuit board or a multi-layer circuit board.

Hereinafter, the first connector40and the second connector70will be described in more detail, on the assumption that the first circuit32is provided on a surface on the second board60side of a board body31of the first board30, and the second circuit62is provided on the first board30side of a board body61of the second board60.

First Connector

The first connector40is a connector that is mounted on the first board30. A through hole31his formed in the board body31of the first board30. Here, the through hole31hhas a square shape. The first circuit32is formed on at least a portion of the periphery of the through hole31hon a surface of the board body31on the second board60side.

The first connector40includes a connector housing42and a first terminal50.

The connector housing42is made of an insulating material such as resin. The connector housing42is disposed in the through hole31hwhile holding the first terminal50, and is held by the first board30. In this manner, the first terminal50is held at a constant position and in a constant orientation with respect to the first board30.

The first terminal50is a member formed by, for example, pressing a metal plate, and includes a first board-side end portion52, a first terminal portion54, and an intermediate portion56.

The first board-side end portion52is electrically and mechanically connected to the first circuit32. Here, “the first board-side end portion52is electrically and mechanically connected to the first circuit32” means the first board-side end portion52and the first circuit32are connected to each other in such a manner that an electrical current can flow between the first board-side end portion52and the first circuit32, and the first board-side end portion52and the first circuit32are held so as to maintain a constant positional relationship. For example, if the first board-side end portion52is soldered to the first circuit32, the first board-side end portion52is electrically and mechanically connected to the first circuit32. This also applies to the relationship between a second board side connection portion73and the second circuit62(described later).

The first terminal portion54is held by the connector housing42. The orientation of the first terminal portion54held in the connector housing42is an orientation suitable for connection to a second terminal portion74of the second connector70, and in this case, the orientation is perpendicular to the first board30.

The intermediate portion56is provided between the first board-side end portion52and the first terminal portion54. The intermediate portion56is a portion that connects the first board-side end portion52and the first terminal portion54to each other. The intermediate portion56includes a heat dissipation portion57exposed to the opposite side to the second board60. The heat dissipation portion57is a portion that is exposed from the connector housing42as seen from the opposite side to the second board60. Note that, “the heat dissipation portion57is exposed from the connector housing42as seen from the opposite side to the second board60” means that at least a portion of the heat dissipation portion57is not hidden by the connector housing42but can be seen when seen from the opposite side to the second board60.

The first connector40will be described in more detail.FIG.4is a perspective view showing the first connector40.FIG.5is a perspective view showing the first terminal50. As shown inFIGS.1to5, the first connector40has a configuration in which the first terminal50is held by the connector housing42.

The connector housing42is a component formed by molding resin, for example. The connector housing42includes a housing body portion43formed into a bottomed tubular shape. In this case, the housing body portion43is formed into a square bottomed tubular shape having a square bottom portion44, and a circumferential wall portion45that stands toward one side from the circumference of the bottom portion44.

For convenience, a direction extending along one side of the bottom portion44is the width direction, and a direction orthogonal to the width direction is the front-rear direction (seeFIG.4). The dimension of the housing body portion43in the width direction is substantially the same as the width dimension of the through hole31hin the same direction. In this manner, the housing body portion43is positioned in the width direction in the through hole31h. The dimension of the housing body portion43in the front-rear direction is set smaller than the dimension of the through hole31hin the same direction. In the state where the housing body portion43is disposed inside the through hole31h, a gap S is formed between the housing body portion43and the through hole31hon one side in the front-rear direction. The intermediate portion56(described later) of the first terminal50can pass through the gap S.

In the present embodiment, slits that extend from an opening of the housing body portion43toward the bottom portion44are respectively formed in front and rear portions of the circumferential wall portion45of the housing body portion43. The slits may be omitted.

The connector housing42includes a pair of holding pieces47. The pair of holding pieces47protrude outward from a portion of the circumferential wall portion45of the housing body portion43, near the opening. In this case, the pair of holding pieces47protrude outward from two edges of wall portions on one side of the circumferential wall portion45in the front-rear direction. A pair of holding grooves48are formed at portions of the pair of holding pieces47that oppose each other. The pair of holding grooves48each have a groove-like shape and extend from the opening side toward the bottom portion44of the housing body portion43. Portions of the pair of holding grooves48near the bottom portion44protrude relative to portions near the opening. Accordingly, the distance between the bottom portions of the pair of holding grooves48is smaller in the region near the bottom portion44than that in the region near the opening.

Outward surfaces47fon the bottom portion44side of the pair of the holding pieces47are located in an intermediate axial portion of the circumferential wall portion45and face toward the bottom portion44. In the state where the housing body portion43is disposed in the through hole31h, the outward surfaces47fcan come into contact with the first board30from the second board60side. Even if the pair of holding pieces47have no peg member80, the pair of holding pieces47protrude outward from the housing body portion43and come into contact with the first board30from the second board60side, and serve to take on an insertion force that is applied when the second connector70is inserted into the first connector40.

The first terminal50is formed by, for example, pressing a band-like metal plate made of copper, a copper alloy, aluminum, an aluminum alloy or the like. One end portion of the first terminal50is the first board-side end portion52, and the other end portion of the first terminal50is the first terminal portion54. A portion of the first terminal50between the first board-side end portion52and the first terminal portion54is the intermediate portion56.

A base end portion of the first terminal portion54is held by the bottom portion44so as to stand upright. The first terminal portion54passes inside the circumferential wall portion45from the bottom portion44and extends toward an opening of the housing body portion43. Here, the first terminal portion54is formed by folding back two end portions of the plate-like portion before being pressed, so as to overlap each other. In other words, the first terminal portion54has a thickness dimension twice the thickness dimension of the plate member serving as the base material thereof. In doing so, the first terminal portion54is unlikely to bend. It is not essential that the first terminal portion54has a two-layer structure formed by folding back a plate or the like. The second terminal portion74is connected to the first terminal portion54. The direction in which the first terminal portion54extends is the same as the direction in which the first terminal portion54and the second terminal portion74are connected to each other. Also, the direction in which the first terminal portion54and the second terminal portion74are connected to each other is the same as the direction in which the first connector40and the second connector70are connected to each other.

Note that the first terminal portion54may be supported by the bottom portion44using any configuration. For example, a configuration is also possible in which the first terminal portion54is held by the bottom portion44due to the first terminal portion54being pressed into the through hole31hformed in the bottom portion44. Alternatively, a configuration is also possible in which the first terminal portion54is held by the bottom portion44as a result of the connector housing42being molded using the first terminal portion54as an insert component.

The intermediate portion56passes the outer side of the bottom portion44and the outer side of the circumferential wall portion45from the base end portion of the first terminal portion54and reaches an axial intermediate position of the circumferential wall portion45. More specifically, the intermediate portion56includes a hanging portion56a, a lateral extending portion56b, a bent portion56c, and an in-hole portion56d.

The hanging portion56aextends in a direction intersecting (here, orthogonal to) the bottom portion44from the base end portion of the first terminal portion54outward of the bottom portion44. The lateral extending portion56bextends in a direction intersecting (here, orthogonal to) the hanging portion56afrom an end portion of the hanging portion56a. The lateral extending portion56bextends toward the opposite side to the pair of holding pieces47in the front-rear direction. The bent portion56cis bent toward the opening of the connector housing42while curving from an end portion of the lateral extending portion56b. The in-hole portion56dextends from an end portion of the bent portion56ctoward the axially intermediate portion of the connector housing42along the axial direction of the connector housing42. A gap is provided between the intermediate portion56and the outer surface of the connector housing42. In the present embodiment, of the first terminal50, the heat dissipation portion57exposed as seen from the opposite side to the second board includes the hanging portion56a, the lateral extending portion56b, and the bent portion56c. The hanging portion56a, the lateral extending portion56b, and the bent portion56c, which are an example of the heat dissipation portion57, can also be understood as being portions protruding to the opposite side to the second board60with respect to the connector housing42.

Also, the bent portion56cis not held by the connector housing42and the first board30. While the first terminal portion54has a two-layer folded structure, the bent portion56cis a single plate structure and thinner than the first terminal portion54. In addition, since the bent portion56cis curved, the entirety of the bent portion56can be easily deformed. For this reason, in the first terminal50, the bent portion56cserves as a stress absorption portion that can be easily deformed. Also, the stress absorption portion of the first terminal50can be realized as a result of at least either the first terminal portion54being thin or having a shape that enables easy bending of the first terminal portion54.

The first board-side end portion52extends from an end portion of the intermediate portion56that is on the opposite side to the first terminal portion54in a direction intersecting (here, orthogonal to) the direction in which the first terminal portion54extends. The first board-side end portion52extends outward in the opposite direction to the pair of holding pieces47. In the axial direction of the connector housing42, the position at which the first board-side end portion52extends is the same as the end portion of a leg portion84of the peg member80(described later). The first board-side end portion52is electrically and mechanically connected to the first circuit32of the first board30.

The first connector40includes the peg member80.FIG.6is a perspective view showing the peg member80. As shown inFIGS.2to4andFIG.6, the peg member80is a member that is held by the connector housing42and is in contact with the first board30from the second board60side.

More specifically, similarly to the first terminal50, the peg member80is formed by pressing a metal plate or the like. The peg member80may also be made of resin.

The peg member80includes a base portion82and a leg portion84. The base portion82has a plate-like shape. Widths of side portions of the base portion82gradually increase from the end portions on the bottom portion44side, and are largest at an intermediate portion of the base portion82in the extending direction. The maximum dimension in the width direction of the base portion82is smaller than the distance between the pair of holding grooves48on the opening side, and larger than the distance between the pair of holding grooves48on the bottom portion44side.

The leg portion84extends outward from the end portion on the bottom portion44side of the base portion82, then extends from the portion extending outward toward the bottom portion44, and then extends from the portion on the bottom portion44side outward along a direction orthogonal to the axial direction of the connector housing42.

As a result of the base portion82being pressed between the pair of holding grooves48, and the two side portions of the base portion82biting into the bottom portions of the pair of holding grooves48near the bottom portion44, the peg member80is held by the connector housing42. In this state, the leading end portion of the leg portion84is located at the same position in the axial direction of the connector housing42as the first board-side end portion52.

The first connector40is mounted to the first board30as follows. Specifically, the connector housing42is disposed in the through hole31h. In this state, the intermediate portion56can reach the second board60side of the first board30from the outer side of the bottom portion44of the connector housing42through the gap S between the outer circumferential surface of the housing body portion43and the inner circumferential surface of the through hole31h. The first board-side end portion52that is continuous with the leading end portion of the intermediate portion56can come into contact with the first circuit32on the second board60side of the first board30. In this state, the leading end portion of the leg portion84of the peg member80can come into contact with the surface of the first board30on the second board60side. Also, the outward surfaces47fof the pair of holding pieces47may also come in contact with the surface on the second board60side of the first board30. The outward surfaces47fmay be spaced apart from the first board30.

In this state, the first board-side end portion52is electrically and mechanically connected to the first circuit32. For example, the first board-side end portion52is soldered to the first circuit32. As a result, the first connector40is mounted and fixed to the first board30. Note that the leg portion84of the peg member80may also be soldered to the first board30. In this case, a configuration is also possible in which a dummy pattern that is not connected to other circuits is formed on the first board30and the peg member80is soldered to the dummy pattern.

Heat Dissipation Promotion Member

The heat dissipation portion57may be in contact with the heat dissipation promotion member90in a heat conductive manner. The heat dissipation promotion member90is a member for promoting heat dissipation from the first terminal50. The heat dissipation promotion member90is, for example, a member that is thicker than the first terminal50, and is made of a material with high heat conductivity such that heat from the first terminal50is easily transferred thereto. The heat dissipation promotion member90may have a configuration suitable for dissipating heat to the outside, such as a portion exposed to the outside of the case12, a portion having a shape suitable for having an increased surface area (e.g., a fin structure, and a comb-like structure), and the like.

The heat dissipation promotion member90is provided spaced apart from the first board30on the opposite side to the second board60with respect to the first board30. The heat dissipation promotion member90, the first board30, and the second board60are supported in parallel with and spaced apart from each other. For example, a configuration is also possible in which the first board30and the second board60are screwed and fixed to the heat dissipation promotion member90, and at this time, a cylindrical boss portion98is interposed between the heat dissipation promotion member90and the first board30, and another boss portion98is interposed between the first board30and the second board60.

The inward facing surface of the heat dissipation promotion member90opposes the heat dissipation portion57. While the first board30is supported at a constant position with respect to the heat dissipation promotion member90, the heat dissipation portion57is disposed at a position capable of being in contact with the heat dissipation promotion member90in a heat-conductive manner. “The heat dissipation portion57is in contact with the heat dissipation promotion member90in a heat conductive manner” means a case where the heat dissipation portion57is in direct contact with the heat dissipation promotion member90or a case where the heat dissipation portion57is in contact with the heat dissipation promotion member90via a heat conductive member constituted of a solid or a liquid. As the heat conductive member, a material that improves adhesion to the heat dissipation portion57or the heat dissipation promotion member90or that improves the heat conductivity thereof with use of the heat conductive filler (e.g. metal powder) included therein is used. As the heat conductive member, a known heat conductive sheet, a heat conductive grease, or a heat conductive adhesive may be used. Here, an example is shown in which the lateral extending portion56bof the heat dissipation portion57is in contact with the heat dissipation promotion member90via the heat conductive member96a.

A protruding portion92is formed at a portion of the heat dissipation promotion member90that is adjacent to the hanging portion56a. The hanging portion56ais in contact with the protruding portion92in a heat-conductive manner as well. In the present embodiment, the hanging portion56ais in contact with the protruding portion92via the heat conductive member96b.

As a result of the hanging portion56abeing brought into contact with the protruding portion92in a heat conductive manner, heat is likely to be transferred from the heat dissipation portion57to the heat dissipation promotion member90. Note that the protruding portion92is not essential.

The above heat dissipation promotion member90is an example of a receiving portion that comes in contact with the heat dissipation portion57from the opposite side to the second board60in the direction in which the first terminal50and the second terminal portion74are connected to each other. As a result of the heat dissipation promotion member90being in contact with the heat dissipation portion57from the opposite side to the second board60, even if the first terminal50is pressed toward the heat dissipation promotion member90when the first terminal50and the second board60are connected to each other, the resulting force is taken on the heat dissipation promotion member90. Focusing on such a role, the heat dissipation portion57may be in direct contact with the heat dissipation promotion member90, or a heat conductive sheet that is unlikely to deform may be used as the heat conductive member96a. Also, focusing on the function of taking on a force that acts on the heat dissipation portion57, the heat dissipation promotion member90need not be a member suitable for dissipating heat to the outside.

Second Connector

The second connector70includes the second terminal72and a connector housing78.

Similarly to the first terminal50, the second terminal72is formed by pressing a metal plate, for example, and includes a second board side connection portion73and the second terminal portion74.

The second terminal portion74is a portion connected to the first terminal portion54as a result of the first board30and the second board60approaching each other. In the present embodiment, the second terminal portion74has a configuration in which a contact piece76is formed inside a tubular portion75. The tubular portion75is formed into a tubular shape that allows the first terminal portion54to be inserted thereinto, here, a square tubular shape. The contact piece76has a shape that can be elastically deformed inside the tubular portion75. When the first terminal portion54is inserted into the tubular portion75, the contact piece76elastically deforms so as to be pushed away by the first terminal portion54, and the contact piece76is pressed against the first terminal portion54by the elastic restoring force generated by the contact piece76attempt to return to its original shape.

The second board side connection portion73is electrically and mechanically connected to the second circuit62. In the present embodiment, the second board side connection portion73extends from the base end portion of the tubular portion75in a direction intersecting (here, orthogonal to) the axial direction of the tubular portion75. The second board side connection portion73is electrically connected to the second circuit62on the first board30side with respect to the second board60. For example, the second board side connection portion73is soldered to the second circuit62or the like. In this manner, the second terminal portion74is mounted and fixed to the second board60in an orientation of protruding from the second board60toward the first board30.

The connector housing78is a tubular member made of resin or the like. The second terminal portion74is housed in the connector housing78. As a result of the second terminal portion74being inserted into the connector housing42, the second terminal portion74can be guided such that the first terminal portion54is smoothly inserted and connected inside the second terminal portion74. The connector housing78may also be omitted.

Connection Work

An example of connection work between the first terminal portion54and the second terminal portion74will be described.

First, the first board30on which the first connector40is mounted is fixed to the heat dissipation promotion member90. In this state, the lateral extending portion56bof the heat dissipation portion57is in contact with the heat dissipation promotion member90via the heat conductive member96a. Also, the outward surface of the hanging portion56ais in contact with the protruding portion92of the heat dissipation promotion member90via the heat conductive member96b.

In the above state, the second board60that is kept parallel with the first board30is moved closer to the first board30. Then, the second connector70approaches the first connector40, and the connector housing78is inserted into the connector housing42. As a result, the first terminal portion54is inserted into the second terminal portion74. The first terminal portion54is inserted into the second terminal portion74while pushing away the contact piece76of the second terminal portion74. As a result, a force F1that acts in a direction toward the base end side also acts on the first terminal portion54. The force F1of the first terminal portion54that acts in a direction toward the base end side is transferred to the connector housing42. The connector housing42is in contact with a surface on the second board60side of the first board30via the peg member80. As a result, the force F1of the first terminal portion54that acts in a direction toward the base end side is taken on by the peg member80that is in contact with the first board30(see F2).

Also, the intermediate portion56of the first terminal50is in contact with the heat dissipation promotion member90as the receiving portion. For this reason, the force of the first board30moving toward the base end side is received by the heat dissipation promotion member90serving as the receiving portion as well (see F3).

Even if the force F1that acts on the first terminal portion54is transferred to the intermediate portion56, the bent portion56cfunctions as a stress absorption portion that deforms in accordance with the force F1. Accordingly, the force F1becomes unlikely to be transferred to the first board-side end portion52as is. As a result, the electrical and mechanical connection state between the first board-side end portion52and the first circuit32can be favorably maintained.

Also, the first board-side end portion52is connected to the first circuit32of the first board30from the second board60side, and thus, even if the force F1is transferred to the first board-side end portion52, the force can be effectively received by the first board30(see F4).

Also, since the first board-side end portion52is pressed in the direction toward the first circuit32, the electrical and mechanical connection state between the second terminal72and the second circuit62can also be favorably maintained.

Effects

According to the board module20or the electrical junction box10with the above configuration, the connector housing42is disposed in the through hole31hformed in the first board30, and the first terminal portion54is held by the connector housing42. As a result of the first board30and the second board60approaching each other, the first terminal portion54and the second terminal portion74are connected to each other. Here, in order to establish connection between the first terminal portion54and the second terminal portion74, a certain insertion length is required. Accordingly, the first terminal portion54and the second terminal portion74are set to a length that is the insertion length or more. In the present embodiment, since at least a portion of the connector housing42that holds the first terminal portion54is disposed in the through hole31h, it is possible to reduce the size of the connection structure by disposing a portion of the connection structure between the first connector40and the second connector70in the first board30. Also, the distance between the first board30and the second board60can be reduced. Since the first board30can be disposed near the second board60, the thickness dimension of the board module20can be reduced, and further, the size of the electrical junction box10can be reduced. Accordingly, the cost of the board module20and the electrical junction box10can be reduced.

Also, the first terminal50is provided between the first board-side end portion52and the first terminal portion54, and includes the heat dissipation portion57that is exposed as seen from the opposite side to the second board60, and thus heat generated by the first terminal50or the heat transferred to the first terminal50is efficiently dissipated, and the heat dissipation performance of the board module20can be improved.

In addition, as a result of the fact that the heat dissipation performance of the first terminal50can be improved, the first terminal portion54can be downsized. Also, freedom of selection of the material used for the first terminal50can be improved. For example, the first terminal50can be made of aluminum, an aluminum alloy, or the like.

Also, since the heat dissipation portion57protrudes to the opposite side to the second board60with respect to the connector housing42, excellent heat dissipation can be achieved. Note that “the heat dissipation portion57protrudes to the opposite side to the second board60with respect to the connector housing42” means that at least a portion of the heat dissipation portion57can be observed in the state of protruding from the connector housing42toward the opposite side to the second board60, as seen from a direction orthogonal to the connection direction with respect to the connector40.

Also, if the heat dissipation portion57is in contact with the heat dissipation promotion member90in a heat conductive manner, the heat of the first terminal50can be effectively dissipated via the heat dissipation promotion member90.

In addition, in the direction in which the first terminal portion54and the second terminal portion74are connected to each other, if the heat dissipation promotion member90serving as the receiving portion is in contact with the heat dissipation portion57from the opposite side to the second board60, when the first terminal portion54and the second terminal portion74are connected to each other, the force that acts on the first terminal portion54is taken on by the heat dissipation promotion member90. In this manner, an excessive force is unlikely to act on the connection portion between the first board-side end portion52and the first circuit32, and the connection state between the first terminal50and the first circuit32can be favorably maintained.

Also, since the bent portion56cserving as the stress absorption portion is provided between the first board-side end portion52and the first terminal portion54, when connecting the first terminal portion54and the second terminal portion74to each other, the force that acts on the first terminal portion54is mitigated due to deformation of the bent portion56c, and is unlikely to be transferred to the first board-side end portion52. In this manner, an excessive force is unlikely to act on the connection portion between the first board-side end portion52and the first circuit32, and the connection state of the first terminal50and the first circuit32can be favorably maintained. In addition, even if positional displacement occurs between the first board-side end portion52and the first terminal portion54due to expansion and contraction accompanying a change in temperature, the displacement is absorbed by the bent portion56c. In this manner, for example, the solder between the first board-side end portion52and the first circuit32is unlikely to peel off, and the thermal durability is improved.

Also, when the first terminal portion54and the second terminal portion74are connected to each other, the first terminal50is pressed away from the second board60. Since the first board-side end portion52is electrically and mechanically connected to the first circuit32of the first board30from the second board60side, a force that presses the first terminal50can be effectively received by the first board-side end portion52that is in contact with the first board30. Also, the first board-side end portion52is pressed toward the first circuit32, rather than away from the first circuit32. In this manner, the connection state between the first terminal50and the first circuit32is favorably maintained.

Also, the peg member80held by the connector housing42is in contact with the first board30from the second board60side, and thus a force that acts when the first terminal portion54and the second terminal portion74are connected to each other is received by the first board30via the connector housing42and peg member80from the first terminal portion54. If the peg member80is made of metal, the rigidity of the connector housing42made of resin is reinforced, and the first connector40can be reliably positioned on the first board30.

Also, the second board side connection portion73is electrically and mechanically connected to the second circuit62on the first board30side with respect to the second board60. As a result, when the first terminal portion54is connected to the second terminal portion74, a force that acts on the second terminal portion74is received by the second board60. In this manner, the connection state between the second board side connection portion73and the second circuit62is favorably maintained.

Variations

In the present embodiment, an example in which the second connector70provided on the second board60is connected to the first connector40. However, the second connector connected to the first connector40need not be a connector provided on a board. For example, the second connector may be a connector provided on an end portion of a wire harness that includes a plurality of wires.

A configuration in which the first board-side end portion52is connected to the first circuit32, and a configuration in which the second board side connection portion73is connected to the second circuit62are not limited to the above example. For example, a configuration is also possible in which the first board-side end portion52has a pin-like shape and is soldered to the first circuit32while extending through a through hole formed in the first board30. Further, a configuration is also possible in which the second board side connection portion73has a pin-like shape and, in a state of extending through a through hole formed in the second board60, is soldered to the second circuit formed on a surface toward which the second board side connection portion73extends relative to the second board60.

Further, the present embodiment described an example in which the first terminal portion54is inserted and connected to the second terminal portion74. However, a configuration is also possible in which the second terminal portion is inserted and connected to the first terminal portion. For example, the second terminal portion may be formed into a tab-like male terminal, and the first terminal portion may be formed into a tubular female terminal.

Note that the configurations described in the above embodiment and variations can be combined as appropriate as long as no mutual contradictions arise.