JP4750604B2 - Circuit board housing case - Google Patents

Description

  The present invention relates to a circuit board housing case that houses a circuit board and is attached to a vehicle or the like.

  Conventionally, a gas sensor including a sensor element that detects a specific gas component in exhaust gas of an automobile or the like is known. The sensor element of this gas sensor performs detection using the fact that the magnitude or voltage value of the current flowing through itself changes according to the concentration of the specific gas component. In order to flow the current, a sensor control circuit electrically connected to the sensor element is provided outside the gas sensor. The sensor control circuit is electrically connected to an ECU (electronic control unit) that controls electronic control of the automobile, and the detected current of the sensor element is converted into a concentration signal indicating the concentration of a specific gas component by the sensor control circuit. To the electronic control unit). The ECU calculates the concentration of the specific gas component and the air-fuel ratio based on the input detection signal, and adjusts the fuel injection amount in the engine.

  By the way, the sensor control circuit described above is mounted on a circuit board, and this circuit board is accommodated in a case for wiring connection. Since this case is normally assembled under the floor of a vehicle of an automobile, it is desirable that the case itself be configured to have a low height in the vertical direction during assembly (low profile). In order to reduce the height of the case, a case having a bottom wall and a housing part surrounded by a side wall connected at one end to the bottom wall is formed and orthogonal to the vertical direction when the case is assembled to a vehicle. The assembly structure of the case is designed so that the surface direction of the bottom wall is arranged in the direction. Then, a relatively large electronic component constituting the sensor control circuit is arranged on one plate surface (hereinafter referred to as “back surface”) side of the circuit board, and the other plate surface (hereinafter referred to as “main surface”). A relatively small electronic component that constitutes the sensor control circuit is disposed on the circuit board, and the circuit board is accommodated in the accommodating portion so that the main surface faces the bottom wall, and between the main surface and the bottom wall of the circuit board. The case may be configured so that the distance between the two becomes smaller.

In addition, the case is placed so that the lead wires for electrical connection between the sensor control circuit and the external circuit such as the gas sensor and ECU are pulled out from the case in the horizontal direction when the case is assembled to the vehicle. Configure. When designing a case like this, it is difficult to house a circuit board with lead wires connected in advance in the case, and it is difficult to seal the lead position of the case lead wire. In some cases, pin terminals (terminal wires) are interposed between the wires (input / output cables) and the pin terminals are embedded in a case (casing) in advance by insert molding. The circuit board and the lead wire are respectively connected to both ends of the pin terminal. Since the connection between the pin terminal and the circuit board is performed in the housing portion, in order to improve the workability in the connection, an electronic component penetrating the circuit board in its thickness direction and disposed on the circuit board An electrically connected through-hole conductor is provided. Then, the pin terminal may be erected from the bottom wall of the case so that the pin terminal can be easily inserted into the through-hole conductor when the circuit board is accommodated in the case (see, for example, Patent Document 1). By doing so, the soldering work between the through-hole conductor and the pin terminal of the circuit board accommodated in the case can be easily performed.
JP 2003-344337 A

  However, when the circuit board is housed in the case of the configuration of Patent Document 1, and the circuit board is sealed by filling the case with a filler in order to ensure the water-tightness of the circuit board and protect it from the environment, Between the pin terminal fixed to the bottom wall of the case (in other words, embedded in the bottom wall) and the circuit board fixed to the pin terminal by soldering due to the influence of thermal expansion of the filler. There is a possibility that a load is applied to the soldered portion and the solder floats or cracks, resulting in poor contact.

  The present invention has been made to solve the above-described problems, and while realizing a low profile, a pin terminal interposed in connection between a circuit board housed inside and an external circuit, and the circuit board An object of the present invention is to provide a circuit board housing case capable of maintaining the reliability of electrical connection for a long period of time.

In order to achieve the above object, a circuit board housing case according to a first aspect of the present invention has a bottom wall and a housing portion that is surrounded by a side wall that is connected to one end of the bottom wall and has a top portion that is open. A circuit board housing case in which a circuit board on which through-hole conductors are formed along a direction is housed in the housing portion, and the circuit board is sealed with an insulating filler filled in the housing portion. In order to electrically connect an external circuit and the circuit board, one end portion is disposed in the housing portion and the other end portion is disposed outside the housing portion so that the inside of the side wall of the housing portion is disposed. A pin terminal in which a middle body portion between the one end and the other end is embedded, and the one end of the pin terminal extends away from the side wall from which the pin protrudes, The connection end portion that is a part of In the bent state, it is disposed in the accommodating portion apart from the bottom wall, and the connection end portion of the one end portion is inserted into the through-hole conductor of the circuit board, and the through-hole conductor The bottom wall and the side wall are integrally formed by injection molding so that the middle body portion of the pin terminal is embedded in the side wall, and the one end of the pin terminal is Among these, the front end barrel which is a portion between the connection end and the middle barrel is a first bent portion that extends closer to the bottom wall than its protruding position from the side wall, and the first A second bent portion that extends away from the protruding position and is connected to the connecting end portion while being connected to the tip of the bent portion .

  In addition to the configuration of the invention according to claim 1, the circuit board housing case of the invention according to claim 2 has a height direction from the bottom wall to the top part of the housing part. It is accommodated in the said accommodating part in the form located in the said bottom wall side rather than the center position of this.

Further, the circuit board housing case of the invention according to claim 3, in addition to the configuration of the invention according to claim 1 or 2, viewing the bottom wall from the opening side of the receiving portion along the thickness direction of the bottom wall In this case, at least one part of the bottom wall facing the one end of the pin terminal is formed in a concave shape so as to be farther from the main surface facing the bottom wall of the circuit board. It is characterized by being.

Further, in the circuit board housing case of the invention according to claim 4 , in addition to the configuration of the invention of claim 3 , the terminal arrangement portion of the bottom wall is formed in a convex shape outside the housing portion. It is characterized by.

According to a fifth aspect of the present invention, there is provided a circuit board housing case, in addition to the structure of the fourth aspect of the present invention, and a plurality of ribs protruding outward in the thickness direction on the bottom wall outside the housing portion. The terminal arrangement portion and the portion of the bottom wall other than the terminal arrangement portion are partitioned by a part of the plurality of ribs, and the protruding tips of the plurality of ribs are It is characterized by being aligned on a plane perpendicular to the thickness direction of the wall.

In addition to the configuration of the invention according to any one of claims 1 to 5 , the circuit board housing case of the invention according to claim 6 has a flat plate shape in the pin terminal, and is uneven in the thickness direction. It is characterized in that a shaped reinforcing portion is formed.

In the circuit board housing case according to the first aspect of the present invention, one end portion of a pin terminal in which a middle body portion is embedded in its side wall is disposed in the housing portion, and a connection end portion of the one end portion and a through-hole conductor of the circuit board And the filler is filled in the accommodating portion. One end of the pin terminal extends away from the side wall from which the pin terminal protrudes in the accommodating portion, and is also separated from the bottom wall, so that the whole end portion has a spring property and approaches the bottom wall or the bottom wall. It is possible to bend in the direction away from the center or in the left-right direction. The container is filled with a filler and the circuit board is sealed, but even if the circuit board is misaligned in the container due to thermal expansion of the filler or vibration received by the circuit board housing case from the outside, Stress can be absorbed by bending of one end of the pin terminal. The connecting end is joined to a through-hole conductor provided on the circuit board, and the joining is usually performed by solder or the like. If stress is applied to the joint, the solder may be cracked or floated. However, as in the present invention, one end of the pin terminal bends following the displacement of the circuit board and absorbs the generated stress. As a result, the solder can be prevented from cracking and floating, and the bonding between the pin terminal and the circuit board can be maintained for a long time. In addition, since the pin terminal is embedded in the side wall and the other end portion is disposed outside the housing portion from the side wall, the connection between the external circuit and the pin terminal can be performed on the side of the circuit board housing case, so that the low height Can be realized.
In addition, if the tip body of one end of the pin terminal is configured to be close to the bottom wall while being separated from the bottom wall, the bending position of the connecting end to bend toward the top portion is further increased. Can be approached. Therefore, the connection end and the through-hole conductor of the circuit board can be joined after bringing the circuit board to be joined to the connection end closer to the bottom wall, and thus the overall height of the circuit board housing case can be reduced. Can be realized.

  Further, the circuit board inserts the connection end of the pin terminal into its through-hole conductor and joins it to the pin terminal, but the connection end is bent so as to face the top of the housing portion. Since the through-hole conductor is normally provided so as to penetrate in the thickness direction of the circuit board, the circuit board is accommodated in the accommodating portion with the height direction of the accommodating portion being the thickness direction of the accommodating portion. At this time, as in the invention according to claim 2, if the circuit board is housed in the housing portion in a form in which the circuit board is positioned on the bottom wall side with respect to the center position in the height direction of the housing portion, It can arrange | position in an accommodating part in the state approached by the bottom wall. Accordingly, since the height of the housing portion can be reduced by the amount that the circuit board is brought closer to the bottom wall, the overall height of the circuit board housing case can be reduced.

On the other hand, as in the invention according to claim 3 , if the terminal arrangement portion corresponding to a portion of the bottom wall, where one end portion of the pin terminal faces the bottom wall, is formed in a concave shape, the one end portion of the pin terminal is A wide gap for bending can be secured in the thickness direction of the bottom wall. As a result, when one end portion of the pin terminal is bent, it contacts the bottom wall, and the bending is restricted, so that it is difficult to cause stress on the joint portion between the circuit board and the connection end portion. In addition, the bonding between the pin terminal and the circuit board can be maintained over a long period of time. Such a configuration is particularly effective when the tip body of one end of the pin terminal is close to the bottom wall in order to achieve a low profile of the circuit board housing case.

Moreover, if the terminal arrangement | positioning part formed in concave shape inside the accommodating part among the bottom walls like the invention which concerns on Claim 4 is formed in convex shape in the accommodating part outer side, the bottom wall of the part formed in the concave shape Only the thickness can be prevented from becoming extremely thin. Therefore, the thickness of the bottom wall can be maintained substantially constant between the terminal arrangement portion and the portion excluding the terminal arrangement portion, and there is no partial deviation in the thickness of the bottom wall, so that the circuit board can be accommodated. The rigidity of the case can be maintained.

Furthermore, if a rib is provided outside the bottom wall as in the invention according to claim 5 , the bottom wall can be reinforced to increase the rigidity. In addition, even when the bottom wall is configured such that the position in the thickness direction is shifted between the terminal arrangement portion and other parts as described above, the thickness of the bottom wall can be increased by aligning the protruding tip positions of the ribs. Even when the bottom wall is used to form a circuit board housing case, the height does not partially differ. Therefore, when this circuit board housing case is assembled to another member (for example, a protective cover for protecting the case) In addition, there is an advantage that the assembly of both is not restricted.

By the way, as for the pin terminal, the middle body part is embedded in the side wall of the circuit board housing case. The circuit board housing case having such a configuration is usually molded by injection molding using a resin. Therefore, as in the invention according to claim 6 , if the reinforcing part is formed in the middle body part of the pin terminal, the middle body part can withstand the injection pressure of the material injected into the mold at the time of molding. There will be no variation in the position of the one end portion that will be disposed in the housing portion later, and the pin terminal will not be deformed. Therefore, when the circuit board is assembled to the circuit board housing case in the manufacturing process, the connection end of the pin terminal can be easily inserted into the through-hole conductor of the circuit board.

  Hereinafter, an embodiment of a circuit board housing case embodying the present invention will be described with reference to the drawings. In the present embodiment, a circuit board 40 on which a sensor control circuit interposed between a gas sensor (not shown) attached to an exhaust pipe of an automobile and an ECU (not shown) for electronic control of the automobile is mounted is accommodated. The housing case 20 for this is taken as an example of a circuit board housing case, and the structure thereof will be described.

  First, the sensor unit 10 in which the circuit board 40 is accommodated in the accommodating portion 21 of the accommodating case 20 will be described with reference to FIGS. FIG. 1 is a perspective view of the sensor unit 10 formed by housing the circuit board 40 in the housing portion 21 of the housing case 20 as viewed from the top, back, and left side. FIG. 2 is a perspective view of the state of the sensor unit 10 before the protective cover 60 is attached to the housing case 20 as seen from the plane, back, and left side. The sensor unit 10 according to the present embodiment is used by being mounted under the floor of an automobile. In order to easily grasp the positional relationship of each part of the structure constituting the housing case 20, the sensor unit 10 of the attached automobile is used. Six directions are defined based on the vertical direction, the front-rear direction, and the left-right direction. That is, the up-down direction, the front-rear direction, and the left-right direction used in the present embodiment are directions defined for convenience of explanation, and do not necessarily limit that the sensor unit 10 is attached to the automobile so as to be in the six plane directions. Absent. Further, the vertical direction is also referred to as the vertical direction, and the front-rear direction and the left-right direction are also referred to as the horizontal direction.

  The sensor unit 10 shown in FIG. 1 has six sensor-side lead wires 89 connected to a gas sensor (not shown) with a heater, and four connected to an ECU (electronic control unit) that performs electronic control of the automobile. It is an apparatus for electrically connecting between the ECU side lead wire 79. The sensor unit 10 is configured to obtain a detection current whose magnitude changes in accordance with the gas concentration of a specific component in the exhaust gas by passing an electric current through the gas sensor, convert the detection current into a concentration signal, and transmit the detection signal to the ECU. It has a circuit board 40 on which a sensor control circuit (not shown) is mounted. The circuit board 40 is housed in the housing portion 21 of the housing case 20 made of resin, and is sealed watertight by filling the housing portion 21 with a mold resin 50 such as urethane. The mold resin 50 corresponds to the “filler” in the present invention.

  As shown in FIG. 2, the storage case 20 has an outer peripheral surface (specifically, a front side wall 22, a rear side wall 23, a left side wall 24, a right side wall 25, and a bottom wall 26 constituting the storage case 20. Each outer peripheral surface) is covered with a metal protective cover 60. As a result, when the sensor unit 10 is used with the bottom wall 26 of the housing case 20 facing down under the floor of the automobile, the housing case 20 is protected from impact due to rock jumping or the like. Moreover, the two brackets 61 are provided in the protective cover 60, and the protective cover 60 functions also as a fixture which fixes the sensor unit 10 under the floor of a motor vehicle. The left side wall 24 and the right side wall 25 of the housing case 20 are provided with two sets of engaging portions 27 for attaching the protective cover 60, and the protective covers provided corresponding to the respective engaging portions 27. By being engaged with the engaging portion 62 of 60, the housing case 20 and the protective cover 60 are configured to be firmly fixed as shown in FIG.

  The front side wall 22 and the rear side wall 23 of the housing case 20 are provided with an ECU side connector part 70 and a sensor side connector part 80, respectively. As described above, the ECU-side lead wire 79 and the sensor-side lead wire 89 are electrically connected to each other via the sensor control circuit (not shown) of the circuit board 40 (see FIG. 1). The electrical connection between the circuit board 40 and the ECU-side lead wire 79 and the sensor-side lead wire 89 for that purpose is a pin to be described later embedded in the front side wall 22 and the rear side wall 23 of the housing case 20 in a state of passing through them. This is done via the terminal 90 (see FIG. 7). In the ECU-side connector portion 70 and the sensor-side connector portion 80, the pin terminal 90, the ECU-side lead wire 79, and the sensor-side lead wire 89 are electrically connected.

  More specifically, as shown in an exploded perspective view of the sensor-side connector portion 80 in FIG. 2, six pin terminals 90 are embedded side by side in the rear side wall 23 of the housing case 20, and the rear end of each pin terminal 90 The portions 93 are respectively exposed from the terminal blocks 231 protruding from the rear side wall 23. Then, the core wires of the six sensor-side lead wires 89 are caulked and fixed to each rear end portion 93 and are electrically connected. The structure of the sensor side connector part 80 is a structure for protecting this connection part and maintaining watertightness. A terminal block cap 83 provided with an insertion hole 831 for inserting each sensor side lead wire 89 is provided. The terminal block 231 is covered and fixed to the terminal block 231 together with the connection portion between the rear end portion 93 and the sensor-side lead wire 89 with the rubber packing 82 interposed between the terminal block 231 and the terminal block 231. In addition, a seal rubber 84 is inserted into each insertion hole 831 of the terminal block cap 83 and is interposed between the sensor side lead wire 89 that passes through the inside, thereby maintaining water tightness in the terminal block cap 83. Is made. Further, a terminal block cap cover 81 provided with a hole through which the sensor-side lead wire 89 can be inserted is fitted into the terminal block cap 83 to prevent the seal rubber 84 from coming off. On the other hand, the ECU-side connector portion 70 is a protection structure for a connection portion between the four ECU-side lead wires 79 and the corresponding pin terminals 90. Although the internal structure of the ECU side connector part 70 is not illustrated, it has the same structure as the sensor side connector part 80.

  Next, the housing case 20 will be described with reference to FIGS. FIG. 3 is a perspective view of the housing case 20 as seen in the direction of the arrow from the plane, back surface, and left side surface. FIG. 4 is a plan view of the storage case 20. FIG. 5 is a cross-sectional view of the housing case 20 as viewed in the direction of the arrow from the left side surface along the alternate long and short dash line AA in FIG. 4. FIG. 6 is a plan view of the housing case 20 that houses the circuit board 40. FIG. 7 is a cross-sectional view of the housing case 20 that houses the circuit board 40 as viewed from the left side surface along the one-dot chain line BB in FIG. 6. FIG. 8 is a perspective view of the pin terminal 90. FIG. 9 is a plan view of the pin terminal 90. FIG. 10 is a side view of the pin terminal 90. FIG. 11 is a cross-sectional view of the pin terminal 90 viewed in the direction of the arrows along the one-dot chain line CC in FIG. FIG. 12 is a cross-sectional view of the pin terminal 90 viewed in the direction of the arrows along the one-dot chain line DD in FIG. FIG. 13 is a perspective view of the housing case 20 as seen from the bottom, back, and right side. FIG. 14 is a bottom view of the housing case 20. FIG. 15 is a cross-sectional view of the housing case 20 as viewed in the direction of the arrow from the right side surface along the alternate long and short dash line EE in FIG. 14. FIG. 16 is a cross-sectional view of the housing case 20 as viewed in the direction of the arrow from the right side surface along the alternate long and short dash line FF in FIG. 14.

  As shown in FIGS. 3 to 5, the storage case 20 has a bottom wall 26 having a substantially square shape with rounded corners in plan view, and is upright from the bottom wall 26 and its outer edge. This is a box-shaped case having an accommodating part 21 surrounded by four side walls, that is, a front side wall 22, a rear side wall 23, a left side wall 24, and a right side wall 25 and having a top portion 28 (see FIG. 5) opened. The edge 211 on the opposite side to the edge connected to the bottom wall 26 of each side wall 22-25 is comprised so that it may align with the plane orthogonal to the upright direction of each side wall 22-25. Moreover, the shape of the plate | board surface of each side wall 22-25 is formed horizontally long so that the storage case 20 may become a flat shape (refer FIG. 3).

  In the housing part 21 of the housing case 20, substrate mounting tables 212 are formed at four corner portions of the bottom wall 26 and the side walls 22 to 25. As shown in FIGS. 6 and 7, the accommodating portion 21 accommodates the circuit board 40 on which the sensor control circuit described above is mounted with the thickness direction thereof being the vertical direction. At this time, the four corners of the circuit board 40 are placed on the board mounting table 212, and there is a constant gap between the plate surface (main surface 41) on the bottom wall 26 side of the circuit board 40 and the inner surface 261 of the bottom wall 26. The distance is maintained. A relatively large electronic component (not shown) constituting the sensor control circuit is mounted on the main surface 41 of the circuit board 40, and the sensor control circuit is formed on the back surface 42 opposite to the main surface 41. A relatively small electronic component is mounted. For this reason, the distance between the back surface 42 of the circuit board 40 and the edge 211 of the side walls 22-25 rather than the distance between the main surface 41 of the circuit board 40 and the inner surface 261 of the bottom wall 26 in the accommodating part 21. The height of the substrate mounting table 212 from the inner surface 261 of the bottom wall 26 is determined.

  As shown in FIGS. 3 to 5, on the outer peripheral surfaces of the front side wall 22 and the rear side wall 23 of the housing case 20, a terminal block 221 constituting the ECU side connector part 70 and the sensor side connector part 80 described above. And a terminal block 231 are integrally provided. The terminal block 221 is formed at a position near the right side wall 25 of the front side wall 22 (see FIG. 4) and at a substantially central position in the vertical direction (see FIG. 5). Further, the terminal block 231 is formed at a position near the left side wall 24 of the rear side wall 23 (see FIG. 4) and at a substantially central position in the vertical direction (see FIG. 5). As shown in FIG. 5, the pin terminal 90 is embedded in the rear side wall 23 where the terminal block 231 is formed and in the front side wall 22 where the terminal block 221 is formed. The side wall 23 and the front side wall 22 including the terminal block 221 are respectively penetrated.

  Here, the pin terminal 90 will be described. As shown in FIGS. 8 to 10, the pin terminal 90 is formed by subjecting a plate made of a conductive metal to plastic working. As shown in FIG. 5, the pin terminal 90 has a middle barrel portion 92 embedded in the front side wall 22 at the position where the terminal block 221 is formed and the rear side wall 23 where the terminal block 231 is formed. And a front end portion 91 disposed in the accommodating portion 21 and a rear end portion 93 exposed from the terminal block 221 or the terminal block 231. The front end portion 91 and the rear end portion 93 correspond to “one end portion” and “the other end portion” in the present invention, respectively.

  The middle body portion 92 of the pin terminal 90 is disposed on the housing portion 21 side when buried in the housing case 20, and from the first embedded portion 921 toward the rear end portion 93 side, It is comprised from the 2nd embedding part 922 extended long in the state which extended the width direction (left-right direction when embedding in the storage case 20) of the plate. As shown in FIGS. 11 and 12, the second embedded portion 922 is formed with a concave portion 923 having an oval shape in the thickness direction of the plate body, leaving its own edge portion. Further, on the bottom surface of the concave surface portion 923 that is inside the periphery of the concave surface portion 923, three convex surface portions 924 that are continuous along the longitudinal direction of the oval shape are formed as convex portions in the thickness direction of the plate body. With this configuration, the cross section in the width direction of the second embedded portion 922 (see FIG. 12) and the cross section in the longitudinal direction of the second embedded portion 922 (see FIG. 11) form a zigzag reinforcing structure, and the rigidity of the middle trunk portion 92 Has been increased. Although the storage case 20 is formed by injection molding, the second embedded portion 922 can withstand the injection pressure of the material filled (injected) into the mold when the storage case 20 is formed by having this reinforcing structure. Can do. The concave surface portion 923 and the convex surface portion 924 correspond to the “reinforcing portion” in the present invention.

  Next, as shown in FIGS. 8 to 10, the tip portion 91 of the pin terminal 90 includes a connection end portion 911 erected in a direction orthogonal to the plate surface of the middle body portion 92, and the connection end portion 911. It is comprised from the front-end | tip trunk | drum 914 which connects the 1st embedding part 921 of the middle trunk | drum 92. FIG. Further, the front end barrel portion 914 includes a first bent portion 912 that is bent from the end of the middle barrel portion 92 on the first embedded portion 921 side in a direction orthogonal to the extending direction of the middle barrel portion 92, and the first bent portion 912. The second bent portion 913 is bent from the end in the extending direction of the middle barrel portion 92. The connecting end portion 911 is bent in the direction orthogonal to the extending direction of the middle trunk portion 92 from the end of the second bent portion 913 in the direction opposite to the first bent portion 912, and the first bent portion 912 and the second bent portion 912 As shown in FIG. 10, the bent portion 913 and the connecting end portion 911 form a U shape as viewed from the side. Further, the connection end portion 911 is formed with a wide portion 916 having the same width as the second bent portion 913 on the second bent portion 913 side, and narrower than the wide portion 916 on the distal end side of the wide portion 916. A portion 915 is formed.

  Next, as shown in FIGS. 8 to 10, the rear end portion 93 of the pin terminal 90 extends continuously in the extending direction of the middle barrel portion 92 from the end of the middle barrel portion 92 on the second embedded portion 922 side. A rear end body portion 931 and a connection portion 932 that is connected to the rear end body portion 931 and connects to the ECU side lead wire 79 and the sensor side lead wire 89 are formed. The connecting portion 932 is formed wide in the width direction, and both ends in the width direction are bent in the same direction to form a groove shape, and the lead wire core wire is sandwiched (a shape that can be crimped and fixed).

  As shown in FIG. 5, the pin terminal 90 having such a shape has a middle barrel portion 92 embedded in the front side wall 22 and the rear side wall 23 of the housing case 20, and a rear end portion 93 extending from the terminal blocks 221 and 231. While being exposed to the outside, the distal end portion 91 is exposed in the accommodating portion 21. As shown in FIGS. 3 to 5, the first bent portion 912 of the front end body portion 914 from the protruding position 222 of the front side wall 22 of the front end portion 91 and the protruding position 232 of the rear side wall 23 is located in the bottom wall 26. It arrange | positions in the state extended toward. The second bent portion 913 connected to the end of the first bent portion 912 is disposed so as to extend away from the front side wall 22 and the rear side wall 23 while maintaining a state of being apart from the bottom wall 26 by a certain distance. The connection end 911 is disposed in an upright state from the end of the second bent portion 913 upward (toward the top portion 28). Accordingly, the connection end 911 is elastically held in the accommodating portion 21 so that the connection end portion 911 can be displaced in the vertical direction, the horizontal direction, and the front-back direction by the distal end body portion 914 protruding from the protruding position 222 or the protruding position 232. The connecting end portion 911 is erected upward, and the distal end body portion 914 protrudes from the projecting positions 222 and 232, and the distal end portion 91 as a whole can be bent with springiness.

  By the way, as described above, the circuit board 40 is accommodated in the accommodating portion 21. As shown in FIGS. 6 and 7, the circuit board 40 has through-hole conductors for inserting the connection end portions 911 of the individual pin terminals 90 along the edges at both ends in the front-rear direction when accommodated. 45 are arranged in a line, and each is formed penetrating in the thickness direction. Each of these through-hole conductors 45 is provided at a circuit end of a sensor control circuit (not shown) mounted on the circuit board 40, and is electrically connected to electronic components constituting the sensor control circuit. The through-hole conductor 45 refers to a conductor formed along the inner wall of the through-hole penetrating along the thickness direction of the circuit board 40. In the accommodating portion 21, the circuit board 40 is connected to the through-hole conductor 45 by inserting the connection end portions 911 of the pin terminals 90 into the respective through-hole conductors 45 in a state where the four corners are placed on the board mounting table 212. The end portion 911 is joined by soldering. As a result, the ECU side lead wire 79 and the sensor side lead wire 89 are electrically connected to the sensor control circuit via the pin terminal 90, and the circuit board 40 is positioned by the pin terminal 90 in the accommodating portion 21. It will be in the state supported so that deviation is possible. In this state, the accommodating portion 21 is filled with the above-described mold resin 50 (see FIG. 1), and the circuit board 40 is sealed in a watertight manner.

  As shown in FIGS. 3 to 5, the bottom wall 26 of the housing case 20 is formed with recesses in the terminal arrangement portions 264 and 265 that are rectangular in plan view at two locations on the inner surface 261. In the terminal arrangement portion 264, the tip end portions 91 of the four pin terminals 90 protruding from the wall surface inside the housing portion 21 at the position where the terminal block 221 of the front side wall 22 is formed overlap the bottom wall 26 in the vertical direction. It is formed so as to include the position. Similarly, in the terminal arrangement portion 265, the tip end portions 91 of the six pin terminals 90 protruding from the wall surface inside the housing portion 21 at the position where the terminal block 231 of the rear side wall 23 is formed have the bottom wall 26 in the vertical direction. It is formed so as to include the overlapping position. Due to the concave structure of these terminal arrangement portions 264 and 265, even if the second bent portion 913 of each pin terminal 90 is arranged closer to the bottom wall 26 as shown in FIG. It can be maintained in contact. That is, since the bottom wall 26 does not restrict the vertical displacement of the distal end portion 91 of the pin terminal 90 (bending of the distal end portion 91), the circuit board 40 supported by the pin terminal 90 is more secured to the bottom wall 26. It becomes possible to arrange | position in the position near. In addition, in order to implement | achieve the structure of the metal mold | die which supports the pin terminal 90 embedded at the storage case 20 at the time of shaping | molding, and is extracted after shaping | molding, as shown in FIG.3, FIG.4, the terminal arrangement | positioning parts 264,265 are horizontal. It is formed with a large area.

  Since the terminal arrangement portions 264 and 265 are formed on the inner surface 261 side of the bottom wall 26 as described above, the thickness of the bottom wall 26 is partially reduced. Therefore, the reinforcing structure is provided on the bottom wall 26. As shown in FIGS. 13 to 16, ribs 29 swelled in the thickness direction are provided in a lattice shape in the plate surface direction on the outer surface 262 which is the plate surface outside the accommodating portion 21 of the bottom wall 26. The protruding height of the rib 29, that is, the protruding tip position in the thickness direction of the bottom wall 26 is aligned with a virtual plane S orthogonal to the thickness direction of the bottom wall 26, as shown in FIGS. On the inner surface 261 of the bottom wall 26, the terminal arrangement portions 264, 265 are provided in a state of projecting downward in the thickness direction with respect to the middle bottom portion 263, which is a portion where the terminal arrangement portions 264, 265 are not formed. ing. That is, the middle bottom portion 263 and the terminal arrangement portions 264 and 265 constituting the bottom wall 26 are formed to have substantially the same thickness, and the terminal arrangement portions 264 and 265 are formed in a recessed shape in the accommodating portion 21, so that the middle bottom portion The structure is shifted in the thickness direction with respect to H.263.

  As shown in FIGS. 13 to 16, the displacement for each part is in a range between the position of the middle bottom 263 on the inner surface 261 side of the bottom wall 26 and the position of the protruding tip of the rib 29 in the thickness direction. When the bottom wall 26 is viewed in a plan view, the bottom wall 26 is divided into blocks divided by ribs 29. That is, in the blocks 267 and 268 respectively corresponding to the terminal arrangement portions 264 and 265, the position of the outer surface 262 in the thickness direction of the bottom wall 26 is closer to the position of the protruding tip of the rib 29 (virtual plane S). On the other hand, in the block 266 corresponding to the middle bottom portion 263, the position of the outer surface 262 in the thickness direction of the bottom wall 26 is farther than the blocks 267 and 268 in the position of the protruding tip of the rib 29 (virtual plane S). In other words, the blocks 267 and 268 are formed as recesses shallower than the block 266 with reference to the protruding tip of the rib 29.

  By configuring the bottom wall 26 in this way, the tip 91 of the pin terminal 90 can be brought closer to the bottom wall 26, and the circuit board 40 can be brought closer to the bottom wall 26, thereby realizing a reduction in the height of the housing case 20. Is done. In addition, the partial thinning of the bottom wall 26 due to the recessed portions of the terminal arrangement portions 264 and 265 is also eliminated by configuring the middle bottom portion 263 to have the same thickness as the terminal arrangement portions 264 and 265. Is done. Further, the strength of the bottom wall 26 itself is ensured by the reinforcing structure by the ribs 29. Further, since the positions of the projecting tips of the ribs 29 are aligned, the thickness of the bottom wall 26 as a whole is aligned with the distance between the projecting tips of the ribs 29 and the position of the inner surface 261 in the middle bottom 263. As a result, the height when completed is uniform and no tilt occurs.

  Needless to say, the present invention can be modified in various ways. For example, the position of the outer surface 262 in the thickness direction of the bottom wall 26 is adjusted in units of blocks divided by ribs 29. However, the positions of the terminal arrangement portions 264 and 265 and the middle bottom portion 263 when the bottom wall 26 is viewed in plan view. The position may be used as a separation position as it is, and a step may be formed on the outer surface 262 in the block.

  In addition, as in the housing case 120 shown in FIG. 17, the lead wire 135 for connection to the ECU and the gas sensor and the pin terminal 190 may be connected by a detachable connector 130. In this case, the housing case 120 is provided with a connector engaging portion 170, and the connector engaging portion 170 is formed with a mouth portion 175 into which the distal end portion 131 of the connector 130 can be inserted. Then, the rear end portion of the pin terminal 190 is arranged in a plate shape or a pin shape in the mouth portion 175. On the other hand, an insertion hole 134 into which the rear end portion of the pin terminal 190 is inserted is formed in the front end portion 131 of the connector 130, and a connection terminal for the lead wire 135 is provided therein. Further, an O-ring 133 is provided on the outer periphery of the tip 131 so as to prevent water droplets or the like from entering the mouth 175 by contacting the inner periphery of the mouth 175 when the tip 131 is inserted into the mouth 175. It is good to provide. With such a configuration, when attaching the sensor unit in which the housing case 20 is assembled under the floor of the automobile, the work can be performed with the lead wire 135 removed, and attachment is easy. Here, the tip 131 of the connector 130 is housed in the connector engaging portion 170, but the connector 130 may be externally mounted on the connector engaging portion 170.

  In the present embodiment, the tip body portion 914 to the connection end portion 911 of the tip end portion 91 of the pin terminal 90 are bent in a U-shape, and the connection end portion 911 is directed upward (upper portion 28). However, the present invention is not necessarily limited to this form, and the distal end body portion 914 may extend straight or be bent in an arc shape. That is, the connection end 911 is erected upward, the tip body 914 protrudes from the projecting positions 222 and 232 and is separated from the bottom wall 26, and the entire tip 91 is bent with springiness. Any form can be used.

  The present invention can be applied to a case in which a circuit board on which electronic components are mounted is accommodated and the circuit board is sealed with a filler.

FIG. 3 is a perspective view of the sensor unit 10 formed by housing the circuit board 40 in the housing portion 21 of the housing case 20 as seen from the plane, back surface, and left side surface. It is the perspective view which looked at the mode of sensor unit 10 before attaching protection cover 60 to storage case 20 from the plane, back, and left side. It is the perspective view which looked at the storage case 20 in the arrow direction from the plane, the back surface, and the left side surface. 4 is a plan view of the storage case 20. FIG. It is sectional drawing of the storage case 20 seen in the arrow direction from the left side surface in the dashed-dotted line AA of FIG. 3 is a plan view of a housing case 20 that houses a circuit board 40. FIG. FIG. 7 is a cross-sectional view of the housing case 20 that houses the circuit board 40 as viewed from the left side surface along the one-dot chain line BB in FIG. 6. 3 is a perspective view of a pin terminal 90. FIG. 3 is a plan view of a pin terminal 90. FIG. 3 is a side view of a pin terminal 90. FIG. It is sectional drawing of the pin terminal 90 seen in the arrow direction in the dashed-dotted line CC of FIG. It is sectional drawing of the pin terminal 90 seen in the arrow direction in the dashed-dotted line DD of FIG. It is the perspective view which looked at the storage case 20 from the bottom face, the back, and the right side. 4 is a bottom view of the storage case 20. FIG. It is sectional drawing of the storage case 20 seen in the arrow direction from the right side surface in the dashed-dotted line EE of FIG. It is sectional drawing of the storage case 20 seen in the arrow direction from the right side surface in the dashed-dotted line FF of FIG. It is sectional drawing which shows the structure of the storage case 120 as a modification.

DESCRIPTION OF SYMBOLS 20 Storage case 21 Storage part 22 Front side wall 23 Rear side wall 24 Left side wall 25 Right side wall 26 Bottom wall 28 Top part 29 Rib 40 Circuit board 41 Main surface 45 Through-hole conductor 50 Mold resin 90 Pin terminal 91 Tip part 92 Middle trunk part 93 Rear end portion 222, 232 Protruding position 264, 265 Terminal arrangement portion 911 Connection end portion 912 First bent portion 913 Second bent portion 914 Tip trunk portion 922 Second embedded portion 923 Concave surface portion 924 Convex surface portion

Claims (6)

A circuit board having a bottom wall and a housing part surrounded by a side wall connected at one end to the bottom wall and having an opening at the top and having through-hole conductors formed along the plate thickness direction is housed in the housing part. A circuit board housing case in which the circuit board is sealed with an insulating filler filled in the housing portion,
In order to electrically connect the external circuit and the circuit board, the one end is disposed in the side wall of the housing portion so that one end portion is disposed in the housing portion and the other end portion is disposed outside the housing portion. A pin terminal in which a middle body portion between the portion and the other end portion is embedded,
The one end portion of the pin terminal extends in a direction away from the side wall from which the pin terminal protrudes, and the connection end portion, which is a portion on the tip side of the pin terminal, is bent toward the top portion of the housing portion, Arranged in the housing part away from the wall,
The connection end of the one end is inserted into the through-hole conductor of the circuit board and is joined to the through-hole conductor .
The bottom wall and the side wall are integrally molded by injection so that the middle body portion of the pin terminal is embedded in the side wall,
Of the one end portion of the pin terminal, a front end barrel portion that is a portion between the connection end portion and the middle barrel portion extends so as to be closer to the bottom wall than its own protruding position from the side wall. A circuit board housing comprising: a first bent portion; and a second bent portion that is connected to a distal end of the first bent portion and extends away from the protruding position and is connected to the connection end portion. Case.   The circuit board is housed in the housing part in a form that is located closer to the bottom wall than a center position in the height direction from the bottom wall toward the top part in the housing part. The circuit board housing case according to claim 1. When the bottom wall is viewed along the thickness direction of the bottom wall from the opening side of the housing portion, the terminal arrangement portion is a portion facing at least the one end portion of the pin terminal at one portion of the bottom wall. 3. The circuit board housing case according to claim 1, wherein the circuit board housing case is formed in a concave shape so as to be farther from a main surface facing the bottom wall of the circuit board. The circuit board housing case according to claim 3 , wherein the terminal arrangement portion of the bottom wall is formed in a convex shape outside the housing portion. On the outside of the housing part, the bottom wall is provided with a plurality of ribs protruding outward in the thickness direction,
The terminal placement portion and the portion of the bottom wall other than the terminal placement portion are partitioned by some of the plurality of ribs,
5. The circuit board housing case according to claim 4 , wherein projecting tips of the plurality of ribs are aligned on a plane perpendicular to the thickness direction of the bottom wall. Wherein in the body of the pin terminal is a flat plate-shaped, the circuit board housing case according to any one of claims 1 to 5, characterized in that uneven reinforcing portion is formed in the thickness direction.

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