JP2003222604A - Gas sensor unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas sensor unit that can determine relative position relation of a first casing member, a second casing member, and a gas sensor element to an only specified position relation and also relative position relation with an object for unit installation such as the duct of a car body and vehicle air conditioning system to only one. <P>SOLUTION: The gas sensor unit 100 is formed with an opening 112b for gas introduction, the accommodation 112 of the gas sensor element, and a terminal connector 113 on a first casing member 110. A rectangular parallelepiped shape part of one part of the substrate position setting part 115 of the first casing member 110 is formed as a first convex shape part 111 and a second convex part 121 with a cylindrical shape is separately formed at the bottom of the second casing member 120. Then a control unit 128 for a mounting attitude to control the mounting attitude of the casing member 120 itself to the object to only one is formed on the second casing member 120. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas sensor unit in which a gas sensor element is housed in a casing, and more particularly to a gas sensor unit in which the casing comprises a first casing member and a second casing member.

[0002]

2. Description of the Related Art There are various known gas sensor units in which a gas sensor element is housed in a casing. For example, the gas sensor unit is mounted on a unit mounting target such as a body of an automobile or a duct of an air conditioner for a vehicle. , Which detects changes in the concentration of exhaust gas in the outside air. Specifically, it is used in a mechanism that automatically switches between opening and closing of the flap when the change in the exhaust gas concentration in the outside air exceeds a predetermined level to control the inside / outside air mode. Among such gas sensor units, FIG. 9 shows a gas sensor unit 500 which can be manufactured at low cost by reducing the number of parts and the number of assembling steps.

The gas sensor unit 500 comprises a first casing member 510 having a lid shape, a second casing member 520 having a box shape, and a wiring board 530. In the first casing member 510, a gas sensor element housing portion 512 that houses the gas sensor element 531, a gas introduction opening portion 512b for introducing the gas to be measured from the outside to the gas sensor element 531, and an output signal from the gas sensor element 531 are taken out. A terminal connector portion 513 for forming is formed. The second casing member 520 is provided with a mounting portion 52 for mounting the gas sensor unit 500 to a unit mounting target such as a vehicle body or a vehicle air conditioner duct.
2, and a second casing member 520 for a unit mounting target such as a body of an automobile or a duct of an air conditioner for a vehicle.
A mounting posture restricting portion 528 for restricting the mounting posture of itself to only one is formed. The wiring board 530 includes
A gas sensor element 531 and electronic parts (resistor, capacitor, microcomputer, etc.) are mounted.

In these assembling methods, first, the wiring board 530 on which the gas sensor element 531 and the like are mounted is mounted on the first casing member 510. Specifically, the wiring board 530
While connecting the connection terminal 532 of No. 1 and the board-side connection portion 518b of the connection terminal 518 of the terminal connector portion 513,
The wiring board 530 is sandwiched and fixed by the board fixing portions 514b formed on two opposite sides of the outer periphery of the casing member 510. Then, the first casing member 510 having the wiring board 530 mounted thereon is replaced with the second casing member 520.
Attach to. Specifically, the fitting guide portions 514 formed at the four corners of the first casing member 510 are not
The gas sensor unit 500 is inserted into the casing member 520, the lock portion 523 of the second casing member 520 engages with the recess 516 of the first casing member 510, and the first casing member 510 is fixed to the second casing member 520. Is completed.

[0005]

This gas sensor unit 500 is good in that it is easy to assemble, but when mounting the first casing member 510 to the second casing member 520, the relative positional relationship between the two is unique. There was a problem in that it was not decided on one specific positional relationship. Specifically, the gas sensor unit 500 has the correct positional relationship shown in FIG. 9 and the incorrect positional relationship obtained by rotating the first casing member 510 shown in FIG. 9 by 180 degrees on the same plane. At both times, the first casing member 510 can be fixed to the second casing member 520. Therefore, in the manufacturing process, the worker assembles the first casing member 510 and the second casing member 520 in an erroneous positional relationship, and the gas introduction opening 512b and the gas sensor element 53.
1, the terminal connector portion 513 and the second casing member 5
The relative positional relationship with 20 may be incorrect (see FIG. 3).

Further, in the gas sensor unit 500, a mounting posture restricting portion for restricting the mounting posture of the second casing member 520 to a unit mounting target such as a body of an automobile or a duct of an air conditioner for a vehicle is limited to one. 528 is formed. Therefore, the gas sensor unit 500 assembled in an incorrect positional relationship may be attached to a unit installation target such as a body of an automobile or a duct of an air conditioner for a vehicle in an incorrect positional relationship.

By the way, the gas to be measured flows from a certain direction with respect to the gas sensor unit 500. Therefore, when the gas sensor unit 500 is properly attached to the body of an automobile or the duct of an air conditioner for a vehicle,
The gas inlet opening 512b and the gas sensor element 531 are located in the direction in which the gas to be measured flows, and the terminal connector 5
13 does not block the flow of the gas to be measured to the gas introduction opening 512b. However, as described above, the relative positions of the gas introduction opening 512b, the gas sensor element 531 and the terminal connector 513 are interchanged with respect to the body of the automobile or the duct of the vehicle air conditioner (FIG. 3).
(Refer to FIG. 4), the gas inlet opening 512b is provided by the connector portion 513 and the harness connected to the connector portion 513.
It will interrupt the flow of the measured gas to the.

Therefore, the conventional gas sensor unit 50
In the case of 0, the gas to be measured is less likely to be introduced from the gas introduction opening 512b, and there is a possibility that the change in the concentration of the exhaust gas in the gas to be measured cannot be accurately detected. Therefore, the characteristics of the mechanism for controlling the inside / outside air mode may not be exhibited. Further, since the length of the harness connected to the connector portion 513 is limited, as described above, the position of the connector portion 513 relative to the unit installation target such as the body of the automobile or the duct of the air conditioner for the vehicle may change. By
The harness may sometimes not reach the connector portion 513. Further, even in the gas sensor unit in which the terminal connector portion 513 is not formed in the first casing member 510, the gas sensor unit is attached to the unit attachment target object such as the body of the automobile or the duct of the air conditioner for the vehicle in the wrong positional relationship as described above. In that case, there is a possibility that the change in the concentration of the exhaust gas in the measured gas may not be accurately detected. Specifically, by changing the positions of the gas introduction opening 512b and the gas sensor element 531 with respect to a unit mounting target such as a body of an automobile or a duct of a vehicle air conditioner, the gas introduction opening 512b with respect to the flow of the gas to be measured is changed. And gas sensor element 53
Since the position of 1 changes, it may not be possible to accurately detect the change in the concentration of the exhaust gas in the measured gas.

The present invention has been made in view of the above circumstances, and includes a first casing member, a second casing member,
The relative positional relationship between the gas sensor element and the gas sensor element can be defined as only one specific positional relationship, and further, the relative positional relationship with the unit mounting object such as the body of the automobile or the duct of the air conditioner for the vehicle can be uniquely defined. A gas sensor unit capable of performing the above is provided.

[0010]

A gas sensor unit comprising a gas sensor element and a casing accommodating the gas sensor element, the casing comprising a first casing member and a second casing member for fixing the first casing member.
A first casing member having a casing member, the first casing member including a gas introduction opening for introducing a gas to be measured from the outside to the gas sensor element, and a gas sensor element accommodation portion for accommodating the gas sensor element; The first casing member is fixed to the second casing member in a state where the relative positional relation between the member and the second casing member is one specific positional relation, and other positional relations. When trying to fix the first casing member to the second casing member,
The second casing member has a shape such that the relative positional relationship between the gas introduction opening of the casing member and the gas sensor element housing portion and the second casing member is different, and the second casing member is a second member to the unit mounting object. A mounting posture restricting portion for restricting only one mounting posture of the casing member itself is included, and the relative positional relationship between the first casing member and the second casing member is the specific positional relationship. Only when the first casing member is
It is a gas sensor unit formed so that it can be fixed to a casing member.

In the gas sensor unit of the present invention, the gas inlet opening and the gas sensor element housing portion are formed in the first casing member, and the gas sensor element is housed in the gas sensor element housing portion of the first casing member. For this reason,
The gas sensor element is not arranged at the wrong position with respect to the first casing member, and therefore, the relative positional relationship between the gas introduction opening and the gas sensor element is uniquely determined. By the way, in the gas sensor unit of the present invention, when the first casing member is fixed to the second casing member when the relative relative positional relationship between the first casing member and the second casing member is only one specific positional relationship, When attempting to fix the first casing member to the second casing member with a positional relationship other than, the relative positional relationship between the gas introducing opening of the first casing member, the gas sensor element housing portion, and the second casing member is It has a different arrangement.

However, the first casing member and the second casing member can be fixed to the second casing member only when the relative positional relationship between them is only one specific positional relationship. Is formed in.
Therefore, the first casing member is not fixed to the second casing member in an erroneous positional relationship, so that the relative positional relationship between the gas introduction opening and the gas sensor element and the second casing member is uniquely determined. . Therefore, the relative positional relationship among the first casing member, the second casing member, and the gas sensor element that form the gas sensor unit of the present invention is uniquely determined. For this reason, the gas sensor unit of the present invention has a structure in which an operator can prevent an assembly mistake such as assembling these components in an incorrect positional relationship in the manufacturing process.

Further, the second casing member is provided with a mounting posture restricting portion for restricting only one mounting posture of the second casing member itself to the unit mounting object. Therefore, when the gas sensor unit of the present invention is mounted on a unit mounting target such as an automobile body or a duct of a vehicle air conditioner for use, the gas introduction opening and the gas sensor element and the vehicle body or vehicle air conditioner are attached. It is possible to define only one relative positional relationship with the unit installation target such as the duct. Therefore, in the gas sensor unit of the present invention, as described above, only one relative positional relationship between the gas introduction opening and the gas sensor element and the second casing member is determined. Can be prevented from being attached to.

The first casing member and the second casing member have a shape such that the first casing member can be fixed to the second casing member only when the relative positional relation between the first casing member and the second casing member is only one specific positional relation. Are as follows. For example, the outer shape of the fitting portion between the two is rectangular, and from this shape, the relative positional relationship between the two is not limited to a single specific positional relationship, and one of the specific positional relationships is 180 degrees on the same plane. It is assumed that the casing member can be fixed even when it is rotated by a certain degree, but it is the shape of the casing member formed so that it can be fixed only when it is in a specific positional relation. In addition, the outer shape of the fitting portion of both is a pentagon of the home base shape, and it is clear from the shape of the fitting portion of the both that the relative positional relationship between the two can be fixed only when there is only one specific positional relationship. The shape of the member is also included.

Another solution is a gas sensor unit comprising a gas sensor element and a casing accommodating the gas sensor element, the casing having a first casing member and a second casing member for fixing the same. The first casing member is provided with a gas introduction opening for introducing a gas to be measured from the outside to the gas sensor element, a gas sensor element accommodating portion for accommodating the gas sensor element, and a terminal electrically connected to the gas sensor element. The second casing member includes a connector portion, and the second casing member includes a mounting posture restricting portion for restricting the mounting posture of the second casing member itself to the unit mounting object to only one.
The first casing member and the second casing member are formed such that the first casing member can be fixed to the second casing member only when the relative positional relationship between them is only one specific positional relationship. It is a gas sensor unit which is formed.

In the gas sensor unit of the present invention, the gas inlet opening and the gas sensor element housing portion are formed in the first casing member, and the gas sensor element is housed in the gas sensor element housing portion of the first casing member. Therefore, the gas sensor element is not arranged at an incorrect position with respect to the first casing member, and therefore, the relative positional relationship between the gas introduction opening and the gas sensor element is uniquely determined.

In the gas sensor unit of the present invention, the gas sensor element housing portion and the terminal connector portion are the first.
It is formed on the casing member. The gas sensor element housing portion and the terminal connector portion cannot be formed in the same portion of the first casing member. For this reason, when the first casing member is fixed to the second casing member with only one specific positional relation between the first casing member and the second casing member, and when the first casing member is fixed with other positional relations. When this is attempted, the relative positional relationship between the gas sensor element housing portion and the terminal connector portion of the first casing member and the second casing member differs. Therefore, there is a possibility that a gas sensor unit having an incorrect relative positional relationship between the gas introduction opening, the gas sensor element, and the terminal connector portion and the second casing member may be assembled. If the gas sensor unit with the wrong positional relationship is attached to the unit installation target such as the body of the automobile or the duct of the air conditioner for the vehicle, as described above, the gas to be measured is less likely to be introduced from the gas introduction opening. However, there is a possibility that the change in the exhaust gas concentration cannot be accurately detected. Therefore, the characteristics of the mechanism for controlling the inside / outside air mode may not be exhibited.

However, in the gas sensor unit according to the present invention, the first casing member and the second casing member are connected to the second casing member only when the relative positional relationship between them is one specific positional relationship. It is formed so that it can be fixed to the member. For this reason, the first casing member is not fixed to the second casing member in an erroneous positional relationship, so that the gas sensor element housing portion and the terminal connector portion of the first casing member and the second casing member are not fixed.
Only one relative positional relationship with the casing member is determined. Therefore, the gas introduction opening, the gas sensor element, and the relative positional relationship between the terminal connector portion and the second casing member are uniquely determined. Therefore, the relative positional relationship among the first casing member, the second casing member, and the gas sensor element that form the gas sensor unit of the present invention is uniquely determined. For this reason, the gas sensor unit of the present invention has a structure in which an operator can prevent an assembly mistake such as assembling these components in an incorrect positional relationship in the manufacturing process.

Further, the second casing member is provided with a mounting posture restricting portion for restricting only one mounting posture of the second casing member itself to the unit mounting object. Therefore, when the gas sensor unit of the present invention is mounted on a unit mounting target such as an automobile body or a duct of a vehicle air conditioner for use, the gas introduction opening and the gas sensor element and the vehicle body or vehicle air conditioner are attached. It is possible to define only one relative positional relationship with the unit installation target such as the duct. Therefore, in the gas sensor unit of the present invention, as described above, only one relative positional relationship between the gas introduction opening, the gas sensor element, and the terminal connector portion and the second casing member is determined, and thus the gas sensor having an incorrect positional relationship is used. It is possible to prevent the unit from being attached to the unit attachment target.

Further, in any one of the above-mentioned gas sensor units, at least one of the first casing member and the second casing member has a first position when the relative positional relationship between them is not the specific positional relationship. It is preferable that the gas sensor unit includes an illicit fixing blocker that blocks the fixing of the first casing member to the two casing members.

In the gas sensor unit of the present invention, the illegal fixing can be surely prevented by the illegal fixing preventing portion formed on at least one of the first casing member and the second casing member. Therefore, it is possible to reliably prevent the first casing member from being fixed to the second casing member in an incorrect positional relationship.

Further, the gas sensor unit includes a wiring board which is connected to the gas sensor element and on which electronic parts are mounted, and wherein the illegal fixation preventing portion includes the first casing member and the second casing member. Even when fixed in a specific positional relationship or when attempted to be fixed in a positional relationship other than the specific positional relationship, the electronic component and the gas sensor element mounted on the wiring board are arranged so as to be isolated from each other. The gas sensor unit is

In the gas sensor unit of the present invention, not only when the first casing member is fixed to the second casing member in a specific positional relationship, but also when it is attempted to be fixed in an erroneous positional relationship other than that, it is illegal. The fixing block is arranged so as not to contact the electronic components and the gas sensor element mounted on the wiring board. That is, the gas sensor unit of the present invention has a structure in which the electronic component and the gas sensor element are not damaged by the improper fixing preventing portion when assembled in the manufacturing process.

Further, in the gas sensor unit according to any one of the above, the illegal fixing prevention portion projects inside the first casing member and the inside of the second casing member. The gas sensor unit may be at least one of the second convex portions.

The gas sensor unit according to the present invention is capable of reliably preventing illegal fixing by at least one of the first convex portion and the second convex portion, and is easy to form the illegal fixing preventing portion. . As the gas sensor unit of the present invention, there are cases where convex portions are formed on both the first casing member and the second casing member, and cases where they are formed on only one of them. When forming the convex portion on both the first casing member and the second casing member, for example, the first convex portion is formed on the inner surface of the first casing member, and the inner surface of the second casing member is formed. An example in which the second convex portion is formed is shown. This gas sensor unit
When the first casing member is fixed to the second casing member in the correct positional relationship, that is, the specific positional relationship, the first convex portion and the second convex portion are separated from each other, and both casing members are fixed. Although it is possible, if not, the both convex portions abut and the fixation is impossible.

On the other hand, when the convex portion is formed only on one of the first casing member and the second casing member, for example, the first convex portion is formed only on the first casing member and the second casing member is formed. A part of the bottom surface of the part may have a concave part. This gas sensor unit
Only when the first casing member is fixed to the second casing member in the correct positional relation, that is, the specific positional relation,
The tip of the convex portion is housed in the concave portion to enable fixing, but if not, the first convex portion abuts the bottom surface of the second casing member to make fixation impossible. is there.

Further, in the gas sensor unit, at least one of the first convex portion and the second convex portion has a side surface portion standing upright on the bottom surface of the casing member including itself immediately after molding. It is preferable to use a gas sensor unit that also serves as a deformation preventing portion for preventing the deformation of the gas sensor unit.

For example, when the casing member is formed by resin molding, in consideration of productivity, the resin may be die-cut in a state where the resin is not yet completely cured. Then, there is a possibility that the side surface portion of the casing member that stands upright on the bottom surface may be deformed. However, in the gas sensor unit of the present invention, the convex portion that is the improper fixing prevention portion is also used as the deformation prevention portion of the side surface of the casing member that includes itself. For this reason, it is possible not only to reliably prevent the first casing member from being fixed to the second casing member in an erroneous positional relationship, but also to prevent deformation of the casing member having the convex portion. Become. In addition, when the deformation prevention part is already formed to prevent the deformation of the casing member, if this is also used as the improper fixing prevention part, there is an advantage that the deformation prevention part does not have to be separately formed.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings. Gas sensor unit 100 of the present embodiment
As shown in exploded view in FIG. 1, the lid-shaped first casing member 11 molded by a known resin integral molding method
0, a box-shaped second casing member 120 molded by a known resin integral molding method, and a wiring board 130. The gas sensor element 1 is provided on the first casing member 110.
A gas sensor element accommodating portion 112 for accommodating 31, a gas introducing opening 112b for introducing a gas to be measured from the outside to the gas sensor element 131, and a terminal connector portion 113 for extracting an output signal from the gas sensor element 131 are formed. There is. In the second casing member 120, a mounting portion 122 for mounting the gas sensor unit 100 to a unit mounting target such as a vehicle body or a vehicle air conditioner duct, and a unit such as a vehicle body or a vehicle air conditioner duct. A mounting posture restricting portion 128 is formed for restricting only one mounting posture of itself to the mounting object. A gas sensor element 131 and an electronic component 135 are mounted on the wiring board 130.

Although not shown, the gas sensor element 131 has a first sensitive gas body (for example, S) whose sensor resistance value changes on its surface due to a change in the concentration of an oxidizing gas such as NOx.
nO2) and a second gas-sensitive material (for example, WO) in which the sensor resistance value changes due to a change in the concentration of a reducing gas such as HC or CO.
3), an alumina substrate provided with an electric heater as a means for supplying heat to both gas sensitive bodies, an outer cylinder surrounding the outside of the alumina substrate and provided with a ventilation hole, and one end having both gas sensitive bodies And a plurality of element terminal portions connected to the heater and having the other end extended to the outside of the outer cylinder. Needless to say, the gas sensor element 131 is not limited to the above configuration.

In the gas sensor element housing portion 112 of the first casing member 110, a plurality of gas introduction openings 112b are formed in the circumferential direction for allowing the gas to be detected (outside air) to come into contact with the gas sensor element 131. The gas introduction opening 1 of the inside of the gas sensor element housing 112.
A filter 141 (see FIG. 4) having air permeability and water repellency is ultrasonically welded to the gas sensor element 131 side of the formation position of 12b. For example, the gas sensor unit 1
When 00 is attached to a unit attachment target such as a body of an automobile or a duct of an air conditioner for a vehicle, the gas sensor element accommodating portion 112 is likely to be covered with water due to rainfall, car washing or the like, but by providing the filter 141, Wiring board 130 on which gas sensor element 131 and many electronic components are mounted
The waterproof property of the. By providing the filter 141 substantially parallel to the gas introduction direction of the gas introduction opening 112b, it becomes difficult for water drops to directly hit the filter 141, and the waterproof function can be further enhanced.

The gas sensor unit 100 is attached to a unit mounting object such as a body of an automobile or a duct of an air conditioner for a vehicle, and can detect a change in exhaust gas concentration in the outside air. Specifically, when the change in the exhaust gas concentration in the outside air reaches or exceeds a predetermined level, the flap can be automatically opened / closed to be used as a mechanism for controlling the inside / outside air mode of a vehicle. Such a gas sensor unit 100 is assembled as follows.

First, the wiring board 130 on which the gas sensor element 131 and the electronic component 135 are mounted is mounted on the first casing member 110. Specifically, as shown in FIG. 2, the wiring board 130 is mounted so as to be surrounded by board position setting portions 115 having an L-shaped cross section formed at four positions of the first casing member 110. At this time, the gas sensor element 131 mounted on the wiring board 130 is attached to the first casing member 1
While being accommodated in the gas sensor element accommodating portion 112 of 10, the terminal connector portion 113 is connected to the connection terminal 132 of the wiring board 130.
The board-side connection portion 118b of the connection terminal 118 is inserted. The connection terminal 132 of the wiring board 130 and the connection terminal 118b of the terminal connector portion 113 are connected by solder or the like. In addition, the first casing member 110 of the present embodiment.
Does not fix the wiring board 130 by the board fixing portion as in the related art.

Next, the first casing member 110 on which the wiring board 130 is mounted is mounted on the second casing member 120. Specifically, the fitting guide portions 114 formed at six positions on the peripheral edge of the first casing member 110 are inserted into the second casing member 120, and the second casing member 1
20 of the first casing member 110 is engaged with the locking portion 123 of the first casing member 110, and
It is fixed to the casing member 120. Then, by pouring an uncured polymer material such as resin or rubber into the entire outer periphery of the fitting portion between the first casing member 110 and the second casing member 120, and then curing it,
First casing member 110 and second casing member 120
A seal member 142 for filling a gap in a fitting portion with
(See FIG. 4).

In this way, the gas sensor unit 100 in which the wiring board 130 is housed in the casing 150 composed of the first casing member 110 and the second casing member 120 is completed. The state inside the casing 150 at this time is shown in FIG. FIG. 4 is a view corresponding to a partial sectional view taken along line EE of FIG. In addition, on the bottom surface of the second casing member 120, as shown in the perspective view of FIG. 1 and the top view of FIG.
The substrate supporting portion 127 is formed. Therefore, as shown in FIG. 4, the cantilevered wiring board 130 fixed to the first casing member 110 only at the connection terminals 132.
The first casing member 110 to the second casing member 1
When fixed to 20, it can be supported and stabilized from the back side.

Here, the structure of the gas sensor unit 100 assembled as described above will be described in detail. In the gas sensor unit 100 of the present embodiment, as described above, the gas introduction opening 112b and the gas sensor element housing portion 112 are formed in the first casing member 100, and the gas sensor element 131 houses the gas sensor element housing of the first casing member 100. It is accommodated in the section 112. For this reason, the gas sensor element 131 is not arranged at an erroneous position with respect to the first casing member 100, and therefore the relative positional relationship between the gas introduction opening 112b and the gas sensor element 131 is uniquely determined.

Further, the first casing member 110 and the second casing member 110
The casing member 120 means both casing members 110,
The first casing member 110 is formed so that the first casing member 110 can be fixed to the second casing member 120 only when the relative positional relationship between the 120 is one specific positional relationship.
Specifically, the first casing member 110 and the second casing member 120 prevent the first casing member 110 from being fixed to the second casing member 120 when their relative positional relationship is not a specific positional relationship. An illegitimate fixing prevention portion is formed for this. In the present embodiment, FIG.
As shown in the perspective view of FIG. 2 and the top view of FIG. 2, a rectangular parallelepiped portion that is a part of the board position setting portion 115 formed on the back surface of the first casing member 110 serves as the first convex shape as the improper fixing prevention portion. As the portion 111, a cylindrical second convex portion 121 is separately formed on the bottom surface of the second casing member 120 at a position adjacent to the deformation preventing portion 126b.

The gas sensor unit 100 as described above is
The first casing member 110 and the second casing member 120
In addition, when the fixing is performed in the correct positional relationship shown in FIG. 3A, that is, in the specific positional relationship, the fixing is possible. Specifically, when it is attempted to fix the first casing member 110 to the second casing member 120, A of FIG.
As shown in FIG. 5A in the -A cut end view, the first convex portion 111 and the second convex portion 121 are in a separated positional relationship, and the both convex portions 111 and 121 are not in contact with each other. Further, since the second convex portion 121 is inserted between the fitting guide portion 114 of the first casing member 110 and the board position setting portion 115, the first casing member 110 is fixed to the second casing member 120. It becomes possible. In addition,
As a matter of course, the deformation prevention portion 126 of the second casing member 120 is also arranged so as not to come into contact with the first casing member 110 when the first casing member 110 is assembled and fixed to the second casing member 120.

On the contrary, as shown in FIG. 3B, when the first casing member 110 is rotated 180 degrees on the same plane, an erroneous positional relationship, that is, a positional relationship which is not a specific positional relationship is obtained.
The first casing member 100 and the second casing member 120
In addition, when trying to fix, it becomes impossible. Specifically, when trying to fix the first casing member 110 to the second casing member 120, B of FIG.
As shown in the -B cut end view of FIG. 5B, the first convex portion 111 and the second convex portion 121 are in contact with each other and cannot be fixed. Therefore, the gas sensor unit 100
Then, the first casing member 110 will not be fixed to the second casing member 120 in an erroneous positional relationship.

Therefore, in the gas sensor unit 100 of the present embodiment, the relative positional relationship between the first casing member 100, the second casing member 120, and the gas sensor element 131 is set to a single specific positional relationship. For this reason, the gas sensor unit 100 of the present embodiment has a structure capable of preventing an assembly mistake in which a worker assembles these components in an incorrect positional relationship in the manufacturing process.

By the way, the gas sensor unit 100 of the present embodiment is, as shown in FIGS. 3 (a) and 3 (b),
First casing member 100 and second casing member 120
The relative position of the gas introducing opening 112b, the gas sensor element housing 112, and the terminal connector 113 and the second casing member 120 when the relative positional relationship with the specific positional relationship is other than that. The relationship will change. However, as described above, the first casing member 110
Is not fixed to the second casing member 120 in an erroneous positional relationship. Therefore, in the gas sensor unit 100 of the present embodiment, the gas introduction opening 112b, the gas sensor element 131, the terminal connector portion 113, and the second casing. Only one relative positional relationship with the member 120 is determined.

Further, the second casing member 120 includes
As shown in FIG. 1, a mounting posture restricting portion 128 for restricting only one mounting posture of the unit mounting target body is formed. Therefore, when the gas sensor unit 100 is mounted on a unit mounting target such as a body of an automobile or a duct of an air conditioner for a vehicle to be used, the gas introduction opening 112b and the gas sensor element 131 are installed.
It is possible to uniquely define the relative positional relationship between a vehicle body and a unit mounting target such as a duct of a vehicle air conditioner. Therefore, in the gas sensor unit 100 of the present embodiment, as described above, only one relative positional relationship between the gas introduction opening 112b and the gas sensor element 131 and the second casing member 120 is determined, so that the gas sensor having an incorrect positional relationship is used. It is possible to prevent the unit from being attached to the body of the automobile or the duct of the air conditioner for the vehicle.

Therefore, in the gas sensor unit 100 of this embodiment, the outside air is introduced from the gas introduction opening 112b without the flow of the outside air to the gas introduction opening 112b being blocked by the connector portion 113 and the harness connected thereto. Therefore, it is possible to accurately detect the change in the concentration of the exhaust gas in the outside air. Therefore, the gas sensor unit 100 of this embodiment can exhibit the characteristics of the mechanism for controlling the inside / outside air mode. Further, as described above, the harness does not reach the connector portion 513 due to the change in the position of the connector portion 113 with respect to the unit mounting target such as the body of the automobile or the duct of the vehicle air conditioner.

The gas sensor unit 1 of this embodiment
In FIG. 00, as can be seen from FIG. 5A, when the first casing member 100 is fixed to the second casing member 120 in a specific positional relationship, the first convex portion 111 and the second convex portion 121 are wired. The gas sensor element 131 and the electronic component 135 mounted on the substrate 130 are arranged so as not to come into contact with each other. Further, as can be seen from FIG. 5B, the first convex portion 111 and the second convex portion 121 also have the gas sensor element 131 mounted on the wiring substrate 130 even when the fixing is performed in an incorrect positional relationship. In addition, it is arranged so as not to contact the electronic component 135. Therefore, the gas sensor unit 100 of the present embodiment has a structure in which the gas sensor element 131, the electronic component 135, and the like are not damaged by the first convex portion 111 and the second convex portion 121 when assembled in the manufacturing process. ing. As a matter of course,
The gas sensor element 131 mounted on the wiring board 130 is also used for the deformation preventing portion 126 of the second casing member 120.
In addition, it is arranged so as not to contact the electronic component 135.

(Modification 1) Next, a gas sensor unit 200, which is a first modification of the gas sensor unit 100 of the embodiment, will be described with reference to the drawings.
In the gas sensor unit 100 of the above-described embodiment, the cylindrical second convex portion 121 is separately formed near the deformation preventing portion 126 of the second casing member 120. In contrast,
The gas sensor unit 200 according to the present modification is different in that the columnar second convex portion is not separately formed, but the other portions are substantially the same. Therefore, the description will be focused on the parts different from the embodiment, and the description of the same parts will be omitted or simplified.

The gas sensor unit 200 of this modification
As can be seen by comparing FIG. 2, which is a plan view of the gas sensor unit 100 of the embodiment, with FIG. 6, which is a plan view of the gas sensor unit 200 of the present modified embodiment, the second casing member 120 of the embodiment includes: The cylindrical second convex portion 12
1 is formed, but a similar convex portion is not formed in the second casing member 220 of this modification. In the second casing member 220 of the present modification, a rectangular parallelepiped second convex portion 226b is formed instead of the deformation preventing portion 126b of the second casing member 120 of the embodiment.

Therefore, the gas sensor unit 200 of the present modified embodiment has the second convex portion 2 which functions as an unauthorized fixation preventing portion.
26b is also used as a deformation preventing portion on the side surface of the second casing member 220. Therefore, it is possible to prevent the first casing member 210 from being fixed to the second casing member 220 in an erroneous positional relationship, and also to prevent the second casing member 220 from being fixed.
The deformation of the second casing member 220 having the convex portion 226b can also be prevented. The gas sensor unit 200 of this modification is the gas sensor unit 1 of the embodiment.
As compared with 00, the second convex portion 2 as an unauthorized fixation preventing portion
The point 26b is not formed separately from the deformation preventing portion. Along with this, the first casing member 2 of the present modified embodiment
In FIG. 10, as can be seen by comparing FIGS. 2 and 6, the first convex portion 211 has a shape extended from the first convex portion 111 of the embodiment.

The gas sensor unit 200 of this modification
Replaces the first casing member 210 with the second casing member 2
When it is attempted to fix the position 20 in the correct positional relationship shown in FIG. 3A, that is, the specific positional relationship, the fixing is possible. Specifically, when attempting to fix the first casing member 110 to the second casing member 120, as shown in FIG.
7A is a cross-sectional view taken along line CC of FIG. 7, the second convex portion 226b does not contact the second casing member 220, and is in a positional relationship separated from the first convex portion 211 not shown. ing. Therefore, the first casing member 110 can be fixed to the second casing member 120.

On the contrary, when the first casing member 210 as shown in FIG. 3B is rotated 180 degrees on the same plane, the first casing member 210 has an erroneous positional relationship, that is, a positional relationship other than the specific positional relationship. The second casing member 2
When trying to fix it to 20, it becomes impossible. Specifically, when trying to fix the first casing member 110 to the second casing member 120, D of FIG.
As shown in FIG. 7B, which is a cross-sectional view taken along line D, the first convex portion 21 is formed.
1 and the 2nd convex-shaped part 226b contact, and fixation becomes impossible. Therefore, in the gas sensor unit 200, the first
The casing member 210 will not be fixed to the second casing member 220 in an erroneous positional relationship.

(Modification 2) Next, a gas sensor unit 300, which is a second modification of the gas sensor unit 100 of the embodiment, will be described with reference to the drawings.
In the gas sensor unit 100 of the embodiment described above, the first casing member 110 and the second casing member 120.
Then, the first convex portion 111 and the second convex portion 121 are formed.
On the other hand, the gas sensor unit 300 of the present modification is different in that the second convex member is not formed in the second casing member, but is substantially the same in other parts. Therefore, the description will be focused on the parts different from the embodiment, and the description of the same parts will be omitted or simplified.

Gas sensor unit 300 of this modification
Is the first convex portion 311 only in the first casing member 310.
In place of the second convex portion, the second casing portion 320 has a concave portion 321 formed in a part of its bottom surface (see FIG. 8). In such a gas sensor unit 300, the first casing member 310 is replaced by the second casing member 320.
In addition, when the fixing is performed in the correct positional relationship shown in FIG. 3A, that is, in the specific positional relationship, the fixing is possible. Specifically, when it is attempted to fix the first casing member 110 to the second casing member 120, A of FIG.
As shown in FIG. 8A, which is a sectional view taken along line A of FIG. 8A, the tip portion of the first convex portion 111 is housed in the concave portion 321 and can be fixed.

On the contrary, as shown in FIG. 3B, the first casing member 310 and the second casing member 320 are set in an erroneous positional relationship in which the first casing member 310 is rotated 180 degrees, that is, a positional relationship that is not a specific positional relationship. When you try to fix it to, it becomes impossible. Specifically, the first
When the casing member 110 is to be fixed to the second casing member 120, as shown in FIG. 8B, which is a sectional view taken along line BB of FIG. 3B, the first convex portion 311 has the second casing. The member 320 comes into contact with the bottom surface of the member 320 and cannot be fixed. Therefore, in the gas sensor unit 300, the first casing member 310 is not fixed to the second casing member 320 in an erroneous positional relationship.

Although the present invention has been described above with reference to the embodiments and modified embodiments, the present invention is not limited to the above embodiments and the like, and within the scope not departing from the gist of the present invention.
It goes without saying that it can be applied with appropriate changes. For example, in the embodiment and the modifications 1 and 2, the first convex portion 11
Although one each of 1,1, 211, 311 and the second convex portion 121, 226b is formed, a plurality of them may be formed. It is preferable to form a plurality of convex portions because it is possible to more reliably prevent the first casing member from being fixed to the second casing member in an erroneous positional relationship. Also,
In the embodiment and the first and second modifications, the gas sensor element 13
Although 1 is mounted on the wiring board 130 together with the electronic component 135, the wiring may be drawn from the wiring board 130 to the outside of the board and separately connected without mounting on the wiring board 130.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing main components of a gas sensor unit 100 according to an embodiment.

FIG. 2 is a diagram showing a main part structure of a gas sensor unit 100 according to an embodiment, and particularly, a first casing member 1
10 is an exploded plan view showing the structures of the inner side surfaces of the first casing member 10 and the second casing member 120. FIG.

FIG. 3 is a top view of gas sensor units 100, 200 and 300 according to the embodiment and the first and second modifications,
(A) is a top view when fixing at a specific position (correct position), and (b) is a top view when fixing at a position (wrong position) other than the specific position.

FIG. 4 is a partially cut sectional view of the gas sensor unit 100 according to the embodiment, which is a partial sectional view taken along line EE of FIG.

5A and 5B are cut end views of the gas sensor unit 100 according to the embodiment, where FIG. 5A is a cut end view taken along line AA of FIG. 3A, and FIG. 5B is a cut end view taken along line BB of FIG. 3B. It is a figure.

FIG. 6 is a gas sensor unit 200 according to the first modification.
FIG. 4 is a diagram showing the structure of the main part of FIG. 4, and is an exploded plan view showing the structure of the inner surfaces of the first casing member 210 and the second casing member 220 in particular.

FIG. 7 is a gas sensor unit 200 according to the first modification.
3A is a cross-sectional view of FIG. 3A, and FIG.
3B is a cross-sectional view taken along the line D-D of FIG.

FIG. 8 is a gas sensor unit 300 according to Modification 2.
3A is a cut end view of FIG. 3A, an end view corresponding to the AA cut surface of FIG. 3A, and FIG. 3B is an end view corresponding to the BB cut surface of FIG. 3B. .

FIG. 9 is an exploded perspective view showing main components of a conventional gas sensor unit 500.

[Explanation of symbols]

131,531 Gas sensor element 110,210,310,510 1st casing part 120,220,320,520 2nd casing part 100,200,300,500 Gas sensor unit 150,250,350 Casing 112b, 512b Gas introduction opening part 112 , 512 Gas sensor element accommodating portions 128, 228, 528 Mounting posture regulating portions 111, 211, 311 First convex portion (illegal fixing blocking portion) 121,226b Second convex portion (illegal fixing blocking portion) 130,530 Wiring board 135 Electronic Components 126, 226, 226b Deformation Blocking Parts 113, 513 Terminal Connector Parts

Continued front page    F term (reference) 2G046 AA11 AA13 AA22 AA23 BB02                       BB04 BD01 BE03 BF05 BG01                       BH08 BJ06 DC13 FB02 FE39                       FE46                 2G060 AA01 AB08 AB10 AB16 AB19                       AE19 AF07 BA01 BB02 BB09                       BB13 BC02 HB06 HC13 HC15                       HC19 HC21 HD03 KA01

Claims (6)

[Claims] 1. A gas sensor unit comprising: a gas sensor element; and a casing accommodating the gas sensor element, the casing having a first casing member and a second casing member fixing the first casing member, The one casing member includes a gas introduction opening for introducing a gas to be measured from the outside to the gas sensor element, and a gas sensor element accommodation portion for accommodating the gas sensor element, and the first casing member and the second casing member. When the first casing member is fixed to the second casing member in a state where the relative positional relationship between the two is one specific positional relationship, and when the first casing member is the second casing member in other positional relationships. At the time of fixing to the member, the gas introduction opening of the first casing member and the gas sensor The second housing member has a shape such that the relative positional relationship between the element housing portion and the second casing member is different, and the second casing member has only one mounting posture of the second casing member itself with respect to the unit mounting target. The first casing member and the second casing member include a mounting posture restricting portion for restricting the first casing member only when the relative positional relationship between them becomes the specific positional relationship. A gas sensor unit formed so as to be fixed to a casing member. 2. A gas sensor unit comprising: a gas sensor element; and a casing accommodating the gas sensor element, wherein the casing has a first casing member and a second casing member for fixing the first casing member. 1 casing member includes a gas introduction opening for introducing a gas to be measured from the outside to the gas sensor element, a gas sensor element housing portion for housing the gas sensor element, and a terminal connector portion electrically connected to the gas sensor element. The second casing member includes a mounting posture restricting portion for restricting only one mounting posture of the second casing member itself with respect to the unit mounting target, and the first casing member and the second casing member are: Only when the relative positional relationship between the two becomes one specific positional relationship, the first casing Gas sensor unit are formed so as to wood can be fixed to the second casing member. 3. The gas sensor unit according to claim 1, wherein at least one of the first casing member and the second casing member has a relative positional relationship between the two. A gas sensor unit provided with an illegal fixation blocking part which blocks fixation of a 1st casing member to a 2nd casing member, when it is not related. 4. The gas sensor unit according to claim 3, further comprising: a wiring board that is connected to the gas sensor element and has an electronic component mounted thereon, and wherein the unauthorized fixation preventing portion includes the first casing member and the first casing member. (2) The electronic component and the gas sensor element mounted on the wiring board are isolated from each other when fixed to the casing member in the specific positional relationship or to be fixed in a positional relationship other than the specific positional relationship. Gas sensor unit that is arranged like. 5. The gas sensor unit according to claim 3 or 4, wherein the improper fixing prevention part is a first convex part projecting inward of the first casing member, and the second casing member. A gas sensor unit that is at least one of the second convex portions projecting inwardly of the gas sensor unit. 6. The gas sensor unit according to claim 5, wherein at least one of the first convex portion and the second convex portion is a side surface erected on a bottom surface of a casing member including self. A gas sensor unit that also functions as a deformation prevention unit for preventing deformation immediately after molding.