JP4824525B2 - Circuit board housing case for gas sensor - Google Patents

Description

The present invention relates to a circuit board housing case for a gas sensor 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 various electronic controls 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. Sent to (electronic control unit). The ECU calculates the concentration of the specific gas component and the air-fuel ratio based on the input concentration signal, and adjusts the fuel injection amount in the engine.

  The sensor control circuit described above is mounted on a circuit board, and this circuit board is housed in a wiring connection case for the purpose of waterproofing and circuit protection, and is sealed with a resin filled in the case. And the lead wire on the gas sensor side and the side lead wire of the ECU are respectively connected to the connector part provided in the case, and each lead wire is electrically connected to the circuit board accommodated in the case via the connector part. Has been.

By the way, the gas sensor is exposed to a high temperature as the internal combustion engine is operated. However, when water is suddenly cooled in such a situation, a pressure difference is generated between the gas sensor and its surroundings, and the gas sensor itself is exposed. There is a case where a load is applied (for example, water enters the gas sensor). In order to prevent this, outside air can be introduced into the gas sensor from the ECU side installed in the atmosphere exposed to the outside air (atmosphere) using the electrical connection path between the ECU and the gas sensor. It has been known. For example, an ECU-side lead wire (ECU-side heater wire) and a gas sensor-side lead wire (sensor-side heater wire) having air permeability are electrically connected using a connector, and air is formed in the connector. A connector has been proposed in which the ends (terminals) of the respective lead wires are respectively arranged in a route (ventilation route) so that air can flow between the two lead wires (for example, see Patent Document 1). In this Patent Document 1, the air permeability between the lead wire on the ECU side and the lead wire on the gas sensor side is realized by a ventilation path formed in a connector for connecting the two. When a substrate is interposed, it is necessary to provide a similar ventilation path in the case.
JP 2004-111388 A

  However, when the case containing the circuit board is filled with the resin as described above, if the resin enters the ventilation path, the inner diameter of the ventilation path is reduced, or the flow path is sometimes blocked. There was a risk of getting lost. In addition, since the case is usually attached to the bottom of an automobile and may be exposed to the outside of the car, it may be made by resin injection molding from the viewpoint of weather resistance and productivity. In some cases, it is difficult to take, the inner diameter of the ventilation path may vary depending on the wear state of the mold and the production lot, and the air flow rate may vary depending on the product.

The present invention has been made to solve the above-described problems, and can smoothly introduce air from the ECU side to the gas sensor side while accommodating a circuit board interposed between the gas sensor and the ECU. An object is to provide a circuit board housing case for a gas sensor .

In order to achieve the above object, a circuit board housing case for a gas sensor according to a first aspect of the present invention has a bottom wall and a concave housing portion surrounded by a side wall rising from the bottom wall, and includes a first external device. A circuit board housing case in which a circuit board electrically connected to each of the two external devices is accommodated in the housing portion between the first external device and the second external device, wherein the lead wire insulates the conductive wire A first external device-side lead wire for making electrical connection between the circuit board and the first external device; A second external device-side lead wire for electrical connection between the circuit board and the second external device, and one end for electrically connecting the circuit board and the first external device-side lead wire. The side is arranged outside the housing part, the other A first pin terminal embedded in a first part of the side wall, and an outer peripheral side of the side wall in the first part, and connected to the first pin terminal, so that a side is disposed in the housing portion A first connector portion having a first hermetic sealing space that is hermetically sealed with respect to the outside while surrounding one end portion of the insulating coating of the first external device side lead wire; and the circuit board; In order to electrically connect the second external device side lead wire, one end side is disposed outside the housing portion, and the other end side is buried in the second portion of the side wall so as to be disposed within the housing portion. The second pin terminal is provided on the outer peripheral side of the side wall in the second part, and surrounds one end portion of the insulating coating of the second external device side lead wire connected to the second pin terminal, Is hermetically sealed to the outside. A second connector portion having a gap and a part of the second connector portion disposed in the circuit board housing case, and a hollow connecting the first hermetic sealing space and the second hermetic sealing space so as to allow ventilation. The circuit board housing case is hermetically sealed by filling the housing with mold resin .

The circuit board housing case for a gas sensor according to a second aspect of the present invention is the circuit board housing case according to the first aspect, wherein the pipe has one end passing through the first portion of the side wall. It protrudes in the 1st airtight sealing space, and the other end part penetrates the 2nd site | part of the said side wall, and protrudes in the said 2nd airtight sealing space, It is characterized by the above-mentioned.

A circuit board housing case for a gas sensor according to a third aspect of the invention is the same as that of the first or second aspect, wherein the pipe is made of metal, and both ends of the pipe have a cross-sectional shape. However, it is deformed so as to be flatter than the cross-sectional shape of the portion between both ends.

According to a fourth aspect of the present invention, in the circuit board housing case for a gas sensor, in addition to the configuration of the first invention, the pipe is embedded in the bottom wall of the housing portion. It is characterized by becoming.

In addition to the configuration of the invention according to claim 4, the circuit board housing case for a gas sensor of the invention according to claim 5 includes the first part and the second part of the side wall, and the bottom wall. The pipes are configured at different positions in the height direction, and the pipes are portions between the first hermetic sealed space and the bottom wall, and between the second hermetic sealed space and the bottom wall. Are each bent.

A circuit board housing case for a gas sensor according to a first aspect of the present invention includes a first hermetic sealing space in a first connector portion surrounding one end portion of a first external device side lead wire having air permeability, and a first air permeability. 2 The first external device is ventilated by a hollow pipe provided in a form traversing the inside of the case in the second hermetic sealing space in the second connector portion surrounding one end portion of the lead wire on the external device side. And the ventilation path | route interrupted | blocked with external air between 2nd external devices can be ensured. In order to reduce the manufacturing cost, the housing part of the circuit board housing case, which is usually formed by injection molding from resin or the like, is configured to have a wide space, and if the inside of the housing part is configured as a ventilation path, sink marks during injection molding The cross-sectional area of the ventilation path may not be constant due to wear of the mold or the mold, and there is a risk that the air flow inside will be difficult to stabilize, but by placing the pipe in the case, the ventilation path can be reliably Can be secured. Further, since the strength of the ventilation path is maintained by the strength of the pipe itself, a structure for reinforcing the strength of the ventilation path is not required, and the circuit board housing case can be reduced in size and height. Furthermore, even when adopting a configuration in which the housing portion is filled with resin in order to protect the circuit board, a ventilation path between the first hermetic sealing space and the second hermetic sealing space is secured by the pipe, The filling resin does not obstruct or block the ventilation path.

  In this way, the pipe can secure a ventilation path between the first hermetic sealing space and the second hermetic sealing space in the circuit board housing case, but as in the invention according to claim 2, By adopting a configuration in which one end and the other end of the pipe are respectively protruded from the side walls, the outside air is cut off, and a ventilation path that consistently connects the first hermetic sealing space and the second hermetic sealing space is ensured. Can be secured.

  And if the one end part and other end part of a pipe are each deform | transformed flat like the invention which concerns on Claim 3, it can prevent that a pipe pulls out from a circuit board accommodation case. The deformation of both ends of the pipe can be easily performed by crushing both ends with a mold while arranging the pipe by insert molding when forming the circuit board housing case by injection molding as described above. If it does in this way, both ends of a pipe can be pinched with a metal mold in the case of injection molding. Thereby, it can prevent that a pipe rotates by the injection pressure of the resin material at the time of injection molding, or shift | deviates from a desired arrangement position. Furthermore, it is only necessary to set the hollow cylindrical pipe as it is in the mold as it is, and it is not necessary to deform both ends in advance. Further, even when the pipe is embedded in the bottom wall, the both ends of the pipe are supported by the mold, so that it is possible to sufficiently prevent the displacement during injection molding. In addition, if a metal pipe is used as such a pipe, sufficient strength can be obtained even if the outer diameter of the pipe is reduced.

  Further, if the pipe is embedded in the bottom wall as in the invention according to claim 4, the height of the accommodating portion (side wall) can be lowered by accommodating the pipe when accommodating the circuit board. It is possible to reduce the size and height of the substrate housing case.

  By the way, depending on the design of the circuit board housing case, the first portion and the second portion of the side wall and the bottom wall may be arranged so as to be shifted in the height direction. In the case where the pipe is embedded in the bottom wall in such a design, if the pipe is bent and arranged as in the invention according to claim 5, the circuit board housing case can be reduced in size while securing the ventilation channel, Low profile can be achieved.

Hereinafter, an embodiment of a circuit board housing case for a gas sensor embodying the present invention will be described with reference to the drawings. In the present embodiment, sensor control interposed between a gas sensor (not shown) attached to the exhaust pipe of an automobile and an ECU (not shown) that performs various electronic controls such as automobile ignition control and air-fuel ratio feedback control. The housing case 20 for housing the circuit board 40 on which the circuit is mounted is taken as an example of the circuit board housing case, and the structure thereof will be described with reference to FIGS.

  FIG. 1 is a perspective view of a state in which the circuit board 40 is accommodated in the accommodating portion 21 of the accommodating case 20 as viewed from the front, the plane, and the right side. FIG. 2 is a perspective view of the housing case 20 as seen from the front, the plane, and the right side in order to explain the structure of the connector portion 60. FIG. 3 is a plan view of the housing case 20. FIG. 4 is a cross-sectional view of the housing case 20 as seen by cutting the part surrounded by the circle A in FIG. 1 with a horizontal plane passing through the vicinity of the pipe 30. FIG. 5 is a cross-sectional view of the housing case 20 as viewed from the direction of the arrows along the one-dot chain line CC in FIG. FIG. 6 is a diagram illustrating a part of a cross section of the housing case 20 as viewed from the direction of the arrow along the alternate long and short dash line DD in FIG. 3. FIG. 7 is a perspective view of the housing case 20 in which the portion of the connector base 70 surrounded by the circle B in FIG. 2 is enlarged.

  Note that the storage case 20 of the present embodiment is used by being attached under the floor of an automobile, and in order to easily grasp the positional relationship of each part of the structure constituting the storage case 20, 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 determined for convenience of explanation, and do not necessarily limit that the housing case 20 is attached to the automobile so as to be in the six-plane directions. Absent. Further, the vertical direction is also referred to as a height direction.

  The housing case 20 shown in FIG. 1 is connected to six lead wires 69 connected to a gas sensor (not shown) with a heater as a first external device and an ECU (electronic control unit) as a second external device. The circuit board 40 on which a sensor control circuit (not shown) interposed between the six lead wires 89 is mounted is accommodated. The sensor control circuit sends a current to the gas sensor to obtain a detection current whose magnitude changes according to the gas concentration of a specific component in the exhaust gas, and converts the detection current into a concentration signal and transmits it to the ECU, This is a circuit for performing energization control of the heater based on a command from the ECU.

  The housing case 20 is formed by resin injection molding and is enclosed by a front side wall 22, a rear side wall 23, a right side wall 24 and a left side wall 25 erected from each side edge of the rectangular bottom wall 26. It has a portion 21 and has a shallow box shape with an open top wall. The above-described circuit board 40 is accommodated in the accommodating portion 21, and the accommodating case 20 is hermetically sealed by filling the accommodating portion 21 with a mold resin 50 such as urethane. Engaging claws 27 for attaching a protective cover (not shown) are provided on the right side wall 24 and the left side wall 25 of the housing case 20. The protective cover is a metal that covers the outer peripheral surfaces of the front side wall 22, the rear side wall 23, the right side wall 24, the left side wall 25, and the bottom wall 26 in order to protect the housing case 20 attached under the floor of the automobile from impacts caused by rock jumping or the like. A cover made of metal and having a bracket for mounting.

  In addition, connector portions 60 and 80 are provided on the front side wall 22 and the rear side wall 23 of the housing case 20, respectively. As described above, the lead wire 69 on the gas sensor side and the lead wire 89 on the ECU side are electrically connected to each other via the sensor control circuit (not shown) of the circuit board 40. For this purpose, electrical connection between the circuit board 40 and the lead wires 69 and 89 is made by pin terminals 79 and 99 (see FIG. 3) 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. ) Is done through. As shown in FIG. 2, the pin terminal 99 is embedded in the rear side wall 23 in a bent state in the vertical direction, and a portion exposed in the accommodating portion 21 has a U shape, and one end faces upward. Are arranged as follows. Although not shown in FIG. 2, the same applies to the pin terminal 79. With such a structure, the circuit board 40 is soldered and electrically connected to the pin terminals 79 and 99 in the accommodating portion 21, and has a spring property. It is supported.

  On the other hand, electrical connection between the pin terminals 79 and 99 and the lead wires 69 and 89 is performed in the connector portions 60 and 80. Here, in the present embodiment, since the gas sensor side connector portion 60 and the ECU side connector portion 80 have the same shape, the structure of the gas sensor side connector portion 60 will be described below. As shown in FIG. 2, the connector portion 60 includes a connector base portion 70 protruding forward from a portion (corresponding to a “first portion” in the present invention) from the approximate center of the front side wall 22 to the right side wall 24. A connector cover 65 that covers the connector base 70 and three packings 66, 67, 68 for keeping the inside of the connector 60 airtight are configured. In the connector base 70, through holes 71 into which six lead wires 69 are inserted independently are formed side by side in the left-right direction. Among the insertion holes 71, the five insertion holes 71 from the right side wall 24 side communicate with each other in five through holes 72 that are provided in the vertical direction in the middle of the protruding direction of the connector base 70. Has been. Similarly, the remaining one insertion hole 71 is communicated with a through hole 75 provided in the up and down direction along with the through hole 72.

  As shown in FIG. 3, the other ends of the six pin terminals 79 embedded in the through holes 72 and 75 so as to penetrate the front side wall 22 are exposed. As shown in FIG. 4, end portions of the lead wires 69 inserted into the insertion holes 71 are disposed in the through holes 72 and 75, and the insulating coating 62 of the lead wire 69 is disposed in the through holes 72 and 75. The core wire 61 exposed from the open end 63 is crimped to the other end of each pin terminal 79 and electrically connected thereto.

  In addition, as shown in FIG. 2, groove portions 73 and 74 that make one round of the outer periphery are formed on the outer periphery on the front side wall 22 side of the through hole 72 of the connector base 70 and on the outer periphery of the protruding tip side of the through hole 72. Is provided. The grooves 73 and 74 are engaged with rubber-made annular packings 66 and 67, respectively, and are brought into contact with the inner peripheral surface of the connector cover 65 that covers the connector base 70. Further, a rubber packing 68 is interposed between the lead wire 69 inserted into the insertion hole 71 of the connector base 70 and the inner peripheral surface of the insertion hole 71. As shown in FIG. 4, these packings 66, 67, and 68 are configured to maintain airtightness in the connector portion 60, particularly in the through holes 72 and 75.

  On the other hand, the connector 80 on the ECU side also has the same structure as the connector 60. That is, as shown in FIG. 3, the connector base 90 that protrudes rearward from a portion (corresponding to a “second portion” in the present invention) from the approximate center of the rear side wall 23 to the left side wall 25 is Through-holes 92 and 95 (through the rightmost wall 24 side are the through-holes 95 and the remaining five are through-holes 92) are formed. One end of each of the six pin terminals 99 embedded in the through holes 92 and 95 so as to penetrate the rear side wall 23 is exposed. The through holes 92 and 95 are communicated with the insertion holes 91 drilled in the protruding direction of the connector base 90, and the core wire of the ECU-side lead wire 89 (see FIG. 1) inserted into each insertion hole 91 passes therethrough. Each pin terminal 99 is electrically connected in the holes 92 and 95. Moreover, although not shown in figure, it is comprised so that the airtightness of each through-hole 92,95 may be maintained by three types of packing similar to the connector part 60. FIG.

  The gas sensor-side connector portion 60 and the ECU-side connector portion 80 having the above-described structure are formed so as to partially overlap in the front-rear direction of the housing case 20. Specifically, as shown in FIG. 3, the through hole 75 of the connector base 70 and the through hole 95 of the connector base 90 are arranged so as to overlap in the front-rear direction. The through hole 75 and the through hole 95 are communicated with each other by a metal pipe 30 that extends straight across the inside of the housing portion 21 of the housing case 20.

  As shown in FIG. 5, the pipe 30 is an elongated hollow member made of a stainless alloy such as aluminum or SUS. The one end 31 side is embedded in a state of penetrating a part of the front side wall 22 and the connector base 70 of the housing case 20, and the one end 31 protrudes into the through hole 75. Similarly, the other end portion 32 side of the pipe 30 is embedded in a state of penetrating a part of the rear side wall 23 of the housing case 20 and the connector base portion 90, and the other end portion 32 projects into the through hole 95. As shown in FIG. 6, the pipe 30 is arranged in the housing portion 21 with a part of the bottom wall 26 of the housing case 20 (an outer peripheral surface facing the bottom wall 26) buried therein. ing. Further, as shown in FIG. 7, one end portion 31 of the pipe 30 protruding into the through hole 75 of the connector portion 60 is deformed so as to be flat in the vertical direction. Although not shown, the other end 32 of the pipe 30 is similarly deformed in the through hole 95.

  In the housing case 20 having such a structure, as shown in FIG. 4, a through hole 75 from which one end portion 31 of the pipe 30 protrudes communicates with the insertion hole 71, and a lead wire 69 is inserted into the insertion hole 71. Has been inserted. Airtightness from the outside air through the insertion hole 71 is sealed by the packing 68, and the airtightness of the through hole 75 is also sealed by the packings 66 and 67 and the connector cover 65. Since the core wire 61 of the lead wire 69 is electrically connected to the pin terminal 79 in the through hole 75 as described above, one end portion of the insulating coating 62, that is, the open end 63 is formed in this airtight sealed space. (Hereinafter referred to as “first hermetic sealing space” 78). As described above, the lead wire 69 can be ventilated. However, since the core wire 61 (conductive wire) of the lead wire 69 is formed of a stranded wire, the gap between the core wire 61 and the gap between the core wire 61 and the insulating coating 62 are air. It is because it becomes possible to distribute. Therefore, the inside of the gas sensor (not shown) and the first hermetic sealing space 78 are communicated with each other through the lead wire 69 in a state of being blocked from the outside air.

  Although not shown, the connector unit 80 has the same structure as the connector unit 60. That is, a space (hereinafter referred to as “second hermetic sealing space” 98) in which the through hole 95 and the insertion hole 91 shown in FIG. 3 are hermetically sealed with the packing and the connector cover is formed, and this second hermetic sealing is performed. One end portion, that is, an open end of the insulating film of the lead wire 89 is disposed in the space 98. Therefore, the inside of the ECU (not shown) and the second hermetic sealing space 98 are communicated with each other through the lead wire 89 in a state of being blocked from the outside air.

  The first hermetic sealing space 78 and the second hermetic sealing space 98 are communicated with each other by the pipe 30 in which the one end portion 31 and the other end portion 32 protrude from the through hole 75 and the through hole 95 as described above. ing. As a result, air is circulated between the gas sensor and the ECU through the lead wire 69, the first hermetic sealing space 78, the pipe 30, the second hermetic sealing space 98, and the lead wire 89 in a state of being blocked from the outside air. A possible ventilation path will be formed. A gas sensor exposed to a high temperature during operation of the internal combustion engine may be subjected to, for example, water and rapidly cooled to cause a pressure difference between the gas sensor and its surroundings. This configuration is such that outside air can be introduced from the ECU side to the gas sensor via the path, and the pressure difference that can be generated in this way is alleviated, so a load is applied to the gas sensor itself (for example, water enters the gas sensor). .) Is prevented.

  The housing case 20 is formed by resin injection molding using a mold (not shown), but the pipe 30 and the pin terminals 79 and 99 described above are embedded in the housing case 20 by insert molding. At this time, the portion of the pipe 30 protruding into the housing portion 21 after the housing case 20 is molded is in a state of being positioned in contact with the mold, so that the pipe 30 is filled when the resin material is filled into the mold. Even if the injection pressure is applied to the pipe 30, the pipe 30 is not displaced. Furthermore, since the one end part 31 and the other end part 32 of the pipe 30 are crushed by the mold and deformed into a flat shape and are directly pressed by the mold, the rotation of the pipe 30 due to the injection pressure is also suppressed. Further, the one end 31 and the other end 32 of the pipe 30 are deformed, so that the pipe 30 is prevented from coming off from the housing case 20. Since the pipe 30 and the pin terminals 79 and 99 are embedded through the front side wall 22 and the rear side wall 23, the through holes 75 and 95 and the accommodating portion are interposed through the through portions of the pipe 30 and the pin terminals 79 and 99. Air does not circulate with 21. Furthermore, the height of the accommodating portion 21 can be reduced by the amount that the pipe 30 is embedded in the bottom wall 26, and thus the accommodating case 20 can be reduced in size and height. On the other hand, if the pipe 30 ensures the ventilation channel in the housing part 21, the ventilation channel is blocked or blocked by the mold resin 50 filled in the housing part 21 to protect the circuit board 40. It will not come off.

  Needless to say, the present invention can be modified in various ways. For example, the pipe 30 has one end portion 31 and the other end portion 32 projecting into the first hermetic sealing space 78 and the second hermetic sealing space 98, respectively. A hole for connecting the accommodating portion 21 and the first hermetic sealing space 78 or the second hermetic sealing space 98 is provided, and one end 31 or the other end 32 of the pipe 30 is disposed in the hole. Also good.

  The pipe 30 has a circular cross section, but may be elliptical or rectangular. Moreover, the pipe 30 may not be a seamless hollow member, and may be, for example, a joint having a seam produced by bending a single plate.

  In the present embodiment, a part of the pipe 30, specifically, the outer peripheral surface facing the bottom wall 26 is embedded in the bottom wall 26, and the other parts are exposed in the housing portion 21. Although it has already been described that the pipe 30 can be pressed by a mold when the housing case 20 is molded by using such a configuration, a part of the pipe 30 extending in the extending direction of the pipe 30 may be embedded in the bottom wall 26. Similar effects can be obtained.

  Of course, the pipe 30 may have a structure that is not exposed in the accommodating portion 21. Specifically, like the pipe 130 of the housing case 120 shown in FIG. 8, it may be configured to be completely embedded in the bottom wall 126 and not exposed in the housing portion 121. In such a case, the housing case 120 is designed such that the one end 131 and the other end 132 of the pipe 130 are exposed from the connector base 170 provided on the front side wall 122 and the connector base 190 provided on the rear side wall 123, respectively. At the time of molding, the one end 131 and the other end 132 may be pressed with a mold.

  Further, when the position of the bottom wall 126 and the position where the one end 131 and the other end 132 of the pipe 130 are exposed from the connector bases 170 and 190 in the vertical direction are different, as shown in FIG. The side 131 and the other end 132 may be bent stepwise and embedded in each wall so as to connect to the bottom wall 126 through the front side wall 122 and the rear side wall 123, respectively. Further, as in the present embodiment, if the one end 131 and the other end 132 are flatly deformed and pressed by a mold, the housing case 120 is molded by an injection machine having a strong injection pressure of the resin material. However, since the rotation of the pipe 130 is suppressed, the pipe 130 can be prevented from being exposed from the bottom wall 126.

  Moreover, the structure of the connector parts 60 and 80 which form the 1st airtight sealing space 78 and the 2nd airtight sealing space 98 is also arbitrary. The case 120 will be described as an example. As shown in FIG. 9, the pin terminal 179 and the one end 131 of the pipe 130 protrude from the connector base 170 of the case 120 toward the front. Between the connector cover 163 that covers all of them and engages with the connector base 170, and the connector base 170, a packing 162 that engages with the outer periphery of the connector base 170 is interposed. The lead wire 169 is connected to the pin terminal 179 disposed in the connector cover 163 through the insertion hole 171 of the connector cover 163, and the packing 164 is interposed between the insertion hole 171 and the lead wire 169. Further, a cover 161 for preventing the packing 164 from falling off is assembled to the connector cover 163. With such a configuration, the entire inside of the connector cover 163 functions as an airtight sealing space, and only one packing 162 is sufficient for the packing engaged with the connector base 170 side.

  Further, like the housing case 220 shown in FIG. 10, the lead wire 269 for connecting to the ECU or the gas sensor and the pin terminal 279 may be connected by a detachable connector 280. In this case, the connector engaging portion 270 is provided on the front side wall 222 of the housing case 220, and the connector engaging portion 270 is formed with a mouth portion 275 into which the distal end portion 281 of the connector 280 can be inserted. In the mouth 275, the end of the pin terminal 279 is arranged in a plate shape or a pin shape. On the other hand, an insertion hole 284 into which the end portion of the pin terminal 279 is inserted into the tip portion 281 of the connector 280 and an insertion hole into which one end portion 231 of the pipe 230 provided in the same configuration as the pipe 130 of the modified example is inserted. 283. The insertion holes 283 and 284 are communicated with each other so as to be ventilated, and a connection terminal for a lead wire 269 is provided in the insertion hole 284. Further, a packing 285 is provided on the outer periphery of the distal end portion 281 to abut against the inner peripheral surface of the mouth portion 275 when the distal end portion 281 is inserted into the mouth portion 275 so as to maintain airtightness in the mouth portion 275. In addition, a packing 286 for keeping the insertion hole 284 hermetically sealed is provided at the insertion port of the lead wire 269 of the connector 280 so that the opening end of the insulating film of the lead wire 269 is disposed in the insertion hole 284. Even in such a configuration, an airtight sealed space can be formed in the mouth portion 275, and a ventilation path that is blocked from outside air is formed between the connector portion provided on the rear side wall (not shown) via the pipe 230. be able to. Here, the tip end portion 281 of the connector 280 is housed in the connector engaging portion 270, but the connector 280 may be externally mounted on the connector engaging portion 270. Of course, you may form the storage case which combined the above-mentioned various connector structures.

  The present invention can be applied to a housing case that requires a ventilation path between both external devices while housing a circuit board interposed between two external devices.

FIG. 6 is a perspective view of the state in which the circuit board 40 is accommodated in the accommodating portion 21 of the accommodating case 20 as viewed from the front, the plane, and the right side. In order to explain the structure of the connector part 60, it is the perspective view which looked at the storage case 20 from the front surface, the plane, and the right side surface. 4 is a plan view of the storage case 20. FIG. FIG. 2 is a cross-sectional view of a housing case 20 as seen by cutting a portion surrounded by a circle A in FIG. 1 with a horizontal plane passing through the vicinity of a pipe 30. It is sectional drawing of the storage case 20 seen from the arrow direction in the dashed-dotted line CC of FIG. It is a figure which shows a part of cross section of the storage case 20 seen from the arrow direction in the dashed-dotted line DD of FIG. FIG. 3 is a perspective view of the housing case 20 in which a portion of the connector base 70 surrounded by a circle B in FIG. 2 is enlarged. It is sectional drawing which looked at the storage case 120 as a modification from the side. It is a perspective view of storage case 120 as a modification. It is sectional drawing which shows the connector structure of the storage case 220 as a modification.

20 Housing Case 21 Housing 22 Front Side Wall 23 Rear Side Wall 24 Right Side Wall 25 Left Side Wall 26 Bottom Wall 30 Pipe 31 One End 32 Other End 40 Circuit Board 60, 80 Connector 61 Core Wire 62 Insulating Film 63 Open End 66-68 Packing 69, 89 Lead wire 70, 90 Connector base 75, 95 Through hole 78 First hermetic sealing space 79, 99 Pin terminal 98 Second hermetic sealing space

Claims (5)

A circuit that has a bottom wall and a concave accommodating portion surrounded by a side wall rising from the bottom wall, and is electrically connected to both of the first external device and the second external device with lead wires. A circuit board housing case for a gas sensor that houses a substrate in the housing section,
The lead wire has a configuration in which a conductive wire is covered with an insulating coating and has air permeability between both ends in the insulating coating, and a first electrical connection between the circuit board and the first external device is performed. An external device-side lead wire, and a second external device-side lead wire that electrically connects the circuit board and the second external device,
In order to electrically connect the circuit board and the first external device side lead wire, the first portion of the side wall is arranged such that one end side is disposed outside the housing portion and the other end side is disposed in the housing portion. A first pin terminal embedded in
The inside of the first part is sealed to the outside while surrounding one end of the insulating coating of the first external device side lead wire provided on the outer peripheral side of the side wall and connected to the first pin terminal. A first connector portion having a first hermetic sealing space sealed in
In order to electrically connect the circuit board and the second external device side lead wire, the second portion of the side wall is arranged such that one end side is disposed outside the housing portion and the other end side is disposed in the housing portion. A second pin terminal embedded in
The inside of the second part is airtight with respect to the outside while surrounding one end of the insulating coating of the second external device side lead wire connected to the second pin terminal and provided on the outer peripheral side of the side wall. A second connector portion having a second hermetic sealing space sealed in
Some of itself is disposed within the circuit board housing case, and a hollow pipe that connects between the first hermetically sealed space and the second hermetically sealed space breathable, the mold resin The circuit board housing case for a gas sensor is characterized in that the inside of the circuit board housing case is hermetically sealed by filling the housing portion. The pipe has one end passing through the first part of the side wall and protruding into the first hermetic sealing space, and the other end passing through the second part of the side wall. The circuit board housing case for a gas sensor according to claim 1, wherein the circuit board housing case projects into the second hermetic sealing space. 3. The pipe according to claim 1, wherein the pipe is made of metal, and both ends of the pipe are deformed so that a cross-sectional shape thereof is flatter than a cross-sectional shape of a portion between the both ends. A circuit board housing case for the gas sensor described. The circuit board housing case for a gas sensor according to any one of claims 1 to 3, wherein the pipe is embedded in the bottom wall of the housing portion. The first part and the second part of the side wall and the bottom wall are configured at different positions in the height direction, and the pipe is located between the first hermetic sealing space and the bottom wall. The circuit board housing case for a gas sensor according to claim 4, wherein a portion between the second hermetic sealing space and the bottom wall is bent.

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