TWI593947B - Pressure sensor - Google Patents

Description

Pressure sensor

The invention relates to a pressure sensor.

Patent Document 1 discloses a pressure sensor that displays a pressure of a fluid to be measured measured by a pressure detecting element in a digital manner. In such a pressure sensor, for example, a component such as a circuit board on which a pressure detecting element is mounted and a liquid crystal display element are stacked and housed in a casing composed of a front frame portion and a base member. [Patent Document] [Patent Document 1] Japanese Patent Laid-Open No. Hei 10-142090. In the above-described pressure sensor, the circuit board to which the pressure detecting element is attached is placed, and is subjected to the pressure of the fluid to be measured. The portion where the pressure detecting element is supported must be firmly fixed to the frame or the like in order to withstand the high pressure from the fluid to be measured. Therefore, as a method of fixing the circuit board to the casing or the like to which the pressure detecting element is attached, it is necessary to use a screw fixing method or a thermal caulking method which can be surely fixed. However, the screw fixing method or the hot caulking method is a laborious work, which may hinder the simplification of the assembly of the pressure sensor.

The present invention has been made to solve the above problems, and an object thereof is to provide a pressure sensor which is easy to perform assembly work.

[Means for Solving the Problem] In order to achieve the above-described purpose, the pressure sensor can detect the pressure of the fluid to be measured, and includes a base member including an introduction portion for introducing the fluid to be measured, and a pressure detecting element. Measuring the pressure of the fluid to be measured introduced from the introduction portion; the circuit board is stacked on the base member, and the pressure detecting element is mounted on the circuit board; the fixing member is disposed on the base plate and sandwiched between the base plate and the base On the opposite side of the component, the circuit board is sandwiched between the fixed component and the base component, and the fixing component is provided with a holding portion extending toward the base member side, and the holding portion and the base An inner engagement portion is provided between the elements, and the inner engagement portion fixes the base member and the fixed component by partially engaging one of the components on the other side with the other component. A cover member is attached and fixed, and the cover member is disposed outside the inner engagement portion to suppress deformation of a portion where the inner engagement portion is provided.

According to the above configuration, the base member, the circuit board, and the fixing member are stacked in order, and the fixing member that is disposed on the opposite side of the base member from the circuit board by the inner engaging portion, and the base member With this simple action, the circuit board can be fixed to the fixed part. Further, by arranging the cover member fixed to the base member on the outer side of the inner engagement portion, the deformation of the portion where the inner engagement portion is provided is restricted, specifically, the deformation in the outwardly extending direction. When the engagement state of the inner engagement portion is released, the portion where the inner engagement portion is provided must be deformed in the outward opening direction, and this deformation is suppressed by the pressing of the cover member, thereby releasing the engagement of the inner engagement portion. It is quite difficult. As a result, the fixing member and the base member are fixed by the engagement of the circuit board, and the fixing structure is easy to assemble, and is also a stable fixing structure capable of withstanding the pressure generated from the fluid.

In the above configuration, the inner engaging portion includes an engaging claw and an engaging recess, and the engaging claw is provided in the holding portion and protrudes toward the base member side, and the engaging recess is provided in the base member, and The engagement claw is engaged with the auxiliary engagement recessed portion, and the auxiliary engagement recess is adjacent to the base end side of the engagement claw, and is open to the base element side, and the base element is provided with an auxiliary The engaging claws are inserted into the auxiliary engaging recesses.

In this case, in order to release the engagement of the inner engaging portion, it is necessary to deform the portion in which the inner engaging portion is provided to the engaging width of the engaging claw and the engaging recess, and the engaging width of the insertion recess and the auxiliary engaging claw. The sum of the above. Therefore, it is quite difficult to release the engagement of the inner engaging portion. Further, it is possible to ensure the same degree of engagement width with about half of the claw length as compared with the case where only one of the engagement claws and the auxiliary engagement claws is omitted. Therefore, the inner engaging portion can be provided in a smaller space, thereby improving the design freedom of the pressure sensor. In particular, it is easy to achieve miniaturization of the sensor.

In the above configuration, the cover member is provided with an attachment portion for fixing the attachment aid, and the attachment aid is for attaching the pressure sensor to the installation target. In particular, the mounting portion is provided on a wall portion of the cover member located outside the inner engaging portion.

In this case, the mounting aid is located outside the cover member in a state in which the mounting aid is mounted. Therefore, when the portion having the inner engaging portion is to be deformed in the outward opening direction, it is extremely difficult to deform the cover member in the same direction. As a result, the effect of suppressing deformation of the portion where the inner engaging portion is provided by the cover member is improved.

In the above configuration, an outer engagement portion is provided between the base member and the cover member, and the outer engagement portion is configured to engage a portion of one of the components on the other side with the other component. The seat member is fixed to the cover member, and the outer engagement portion is provided on a surface of the base member that is the same as a surface on which the inner engagement portion is provided.

In this case, in the assembly process, when the fixed parts are stacked and the cover member is attached, it is only necessary to work on the same side of the surface on which the inner engagement portion and the outer engagement portion are provided, so that assembly can be easily performed. .

In the above configuration, the base member is provided with a flange, and the flange is located at a position facing the end of the cover member. Under this circumstance, it is difficult to cause a problem that the article is accidentally hooked to the end of the cover member to cause the cover member to fall from the base member.

In the above configuration, the flange is provided with a detaching recess, and when the cover member is to be removed from the base member, the jig is inserted into the detaching recess. In this case, even in the case where the cover member is firmly fixed to the base member in order to increase the strength of the fixing structure by the inner engaging portion, the cover member can be simply removed by using the jig. Remove the base member. By providing the detaching portion as a concave portion, it is difficult to cause the article to be accidentally hooked to the detaching portion, causing the cover member to fall from the base member.

In the above configuration, the edge portion on the side of the base member of the cover member is disposed at a position overlapping the portion of the cover member located outside the inner engagement portion in the direction along the edge portion. There is a protruding portion that protrudes toward the side of the base member. In this case, the distance from the portion overlapping the inner engaging portion to the edge portion of the cover member becomes long. Therefore, when the portion having the inner engaging portion is to be deformed in the outward opening direction, it is difficult for the cover member to be deformed in this direction. As a result, it is possible to improve the deformation of the portion where the inner engaging portion is provided by the cover member.

[Effect of the Invention] With the pressure sensor of the present invention, the assembly work can be easily performed.

Hereinafter, an embodiment in which the present invention is embodied as a pressure sensor including a liquid crystal display element will be described. As shown in FIGS. 1 and 2, the pressure sensor 10 is provided with a base member 20 made of synthetic resin. The base member 20 is formed in a bottomed rectangular box shape and includes a quadrangular plate-shaped rear wall 21; the first inner side wall 22 is erected along opposite sides of one side of the rear wall 21; and the second inner side wall 23 The two sides of the other side of the rear wall 21 are erected upright.

A flange 24 that protrudes from the first inner side wall 22 and the second inner side wall 23 is provided at a peripheral portion of the rear wall 21. A recess 24a is provided at a central portion of each side of the flange 24. A cylindrical guide port 21a for taking in the fluid to be measured is provided at a central portion of the rear wall 21. A connection hole 21b is provided in the rear wall 21 by cutting one side of the rear wall 21.

As shown in FIGS. 2 and 5, an engagement groove 25 extending from the edge portion on the opening side is provided at the center portion of the outer surface of the first inner side wall 22. An engagement recess 25a is provided in the engagement groove 25, and the engagement recess 25a extends along the opening edge of the first inner side wall 22, and penetrates the first inner side wall 22. The engagement groove 25 is provided with an auxiliary engagement claw 25b that protrudes toward the outer side along the edge of the engagement recess 25a. The auxiliary engagement claw 25b is formed in a substantially triangular shape in a cross section whose width gradually becomes wider toward the engagement portion 25a side.

As shown in FIGS. 2 and 6, two engagement projections 22a are provided on the outer surface of the first inner side wall 22, and two engagement projections 22a are located in the engagement groove 25 in the direction along the opening edge. side. Further, on the flange 24 of the first inner side wall 22, a detaching recessed portion 26 is provided at a position overlapping each of the engaging projections 22a.

As shown in FIGS. 2 and 5 to 7, a circuit board 30 is disposed on the upper surface of the first inner side wall 22 and the second inner side wall 23 of the base member 20, and detection of pressure is formed on the circuit board 30. Loop, etc. The outer shape of the circuit board 30 is formed to substantially match the outer peripheral shape of the first inner side wall 22 and the second inner side wall 23 of the base element 20, and a recess 30a is provided in a part of the periphery of the circuit board 30, and the recess 30a is provided in the recess 30a. The engagement grooves 25 of the first inner side wall 22 correspond to each other.

A pressure detecting element 31 is attached to a central portion of the lower surface (surface on the side of the base member 20) of the circuit board 30. As shown in FIGS. 5 and 7, the pressure detecting element 31 includes a cylindrical introduction portion 31a that protrudes toward the base member 20, and an O-ring 32 is interposed between the introduction portion 31a and the base member 20. An external connection connector 33 is attached to the lower surface of the circuit board 30. The front end portion of the external connection connector 33 is engaged with the coupling hole 21b of the base member 20. In each of the cross-sectional views shown in FIGS. 5 to 7, the components for mounting the pressure detecting element 31, the external connection connector 33, and the like on the circuit board 30 are simplified.

As shown in FIG. 2 to FIG. 7, on the upper surface side (the side opposite to the base member 20) of the circuit board 30, a diffusion element 40 and a liquid crystal display element 50 are sequentially stacked, and the liquid crystal display element 50 is displayed by pressure detection. The detection result detected by the component 31. In the present embodiment, the diffusing element 40 corresponds to a supporting element.

The diffusing element 40 is a quadrangular plate-shaped member made of synthetic resin, and has substantially the same outer shape as the circuit board 30. A diffusion opening portion 41 having a rectangular shape is provided in a central portion of the diffusing element 40. As shown in FIG. 3, the light-emitting element 34 for display (for backlight) such as an LED mounted on the circuit board 30 is located at an opening portion of the diffusion opening portion 41. The diffusing element 40 diffuses light emitted from the light emitting element 34 toward the liquid crystal display element 50 in the diffusion opening portion 41.

As shown in FIGS. 3 to 7, a connector insertion hole 42 extending along the long side 41a is formed between the long side 41a on one side of the diffusion opening 41 and the peripheral edge portion of the diffusion element 40 in the diffusing element 40. The connector insertion hole 42 penetrates the diffusion element 40. An elastic connector 35 is inserted into the connector insertion hole 42, and the elastic connector 35 electrically connects the liquid crystal display element 50 to the circuit board 30. The elastic connector 35 is a member formed into a flat plate shape by alternately stacking a conductive rubber and an insulating rubber having elasticity. One end side of the elastic connector 35 is connected to an electrode provided on the circuit board 30, and the other end of the elastic connector 35 is connected. The side is connected to the electrode portion of the liquid crystal display element 50.

As shown in FIG. 3 and FIG. 7, the diffusing element 40 is located on the opposite side of the connector insertion hole 42 with the diffusion opening 41 interposed therebetween, and the other long side 41b of the diffusion opening 41 is provided. An elastic support portion 43 for supporting the liquid crystal display element 50 is integrally formed at a portion near the center. The elastic support portion 43 is formed in a bridge shape in which a rectangular plate-shaped portion is connected at two points at both ends thereof, and is a portion that can be bent in the vertical direction (thickness direction).

Specifically, a gap 44 extending along the long side 41b of the other side of the diffusion opening 41 is provided on the side of the diffusion opening 41 of the elastic support portion 43, and the opening for diffusion of the elastic support portion 43 is provided. On the opposite side of the portion 41, a step portion 45 is further provided in the upper and lower directions (thickness direction) than the elastic supporting portion 43. By the gap 44 and the step portion 45, the elastic supporting portion 43 is formed in a bridge shape in which the long rectangular plate-like portion is joined at two points at both ends thereof. The lower surface side (the side of the circuit board 30) of the elastic supporting portion 43 is formed with a recess to thereby increase its curvature. Further, a convex portion 43a that protrudes upward (the side opposite to the circuit board 30) is provided at a central portion of the elastic support portion 43.

As shown in FIG. 6, the portion of the diffusing element 40 that is lowered by the step portion 45 serves as the button mounting portion 46, and the button mounting portion 46 is provided with a button member 60 to be described later. A support wall 47 that is erected on the upper side (the side opposite to the circuit board 30) and a holding piece 48 that is erected on the lower side are provided on the periphery of the diffusing element 40. In the present embodiment, the holding piece 48 corresponds to the holding portion.

As shown in FIG. 2 and FIG. 3, the holding piece 48 is a quadrangular plate-shaped portion provided at a central portion of both sides of the peripheral edge of the diffusing element 40 on the same side as the first inner side wall 22 of the base member 20, and is housed. It is provided in the engagement groove 25 provided in the 1st inner side wall 22 of the base element 20. The inner end portion of the holding piece 48 is provided with an engaging claw 48a that protrudes toward the inner surface side. The engaging claws 48 are formed in a substantially triangular cross section whose width gradually becomes wider toward the base end side of the holding piece 48. An auxiliary engagement recess 48b penetrating the holding piece 48 is provided on the proximal end side of the engaging claw 48a of the holding piece 48.

As shown in FIG. 5, the engaging claw 48a provided in the holding piece 48 is inserted into the engaging recessed portion 25a provided in the first inner side wall 22 of the base member 20. The auxiliary engagement claw 25b provided on the first inner side wall 22 is inserted into the auxiliary engagement recess 48b provided in the holding piece 48. In the present embodiment, the engagement claws 48a, the engagement recesses 25a, the auxiliary engagement claws 25b, and the auxiliary engagement recesses 48b constitute an inner engagement portion.

As shown in FIGS. 4 to 7, the liquid crystal display element 50 and the button element 60 are disposed on the upper surface side (the side opposite to the circuit board 30) of the diffusing element 40. The liquid crystal display element 50 is a member formed into a long rectangular shape as a whole, and is disposed to overlap the diffusion opening portion 41 of the diffusion element 40. As shown in FIG. 7 , an electrode portion is integrally formed on one of the long sides of the back surface of the liquid crystal display element 50 , and the electrode portion is coupled to an elastic connector 35 that protrudes from the connector insertion hole 42 of the diffusing element 40 . The other central portion on the long side of the back surface of the liquid crystal display element 50 is in contact with the protruding portion 43a of the elastic supporting portion 43 on the diffusing element 40. Therefore, one of the long sides of the back surface of the liquid crystal display element 50 is entirely supported by the elastic connector 35, and the other central portion of the long side is supported by the elastic supporting portion 43.

As shown in FIGS. 1 and 4, the pressure sensor 10 is provided with a cover member 70 made of a synthetic resin that covers the outside of the base member 20. The cover member 70 is formed in a bottomed rectangular box shape, and includes a square plate-shaped front wall 71, a first outer side wall 72 that is erected from opposite sides of one side of the front wall 71, and the other side from the front wall 71. The second outer side wall 73 is provided upright on both sides of the opposite side.

A window portion 71a for visually confirming the liquid crystal display element 50 is provided on the front wall 71. As shown in FIGS. 5 to 7, a transparent cover 71b covering the window portion 71a is attached to the inner side of the front wall 71. The transparent cover 71b abuts against the liquid crystal display element 50, and presses the liquid crystal display element 50 to display the liquid crystal. The element 50 is fixed between the transparent cover 71b and the elastic connector 35 and the elastic support portion 43. The front wall 71 is provided with a button opening portion 71c for exposing the button portion of the button member 60.

As shown in FIG. 4, the first outer side wall 72 and the second outer side wall 73 of the cover member 70 are each formed in a long square shape, and a protruding portion 74 that protrudes toward the opening edge side is provided at a central portion on the opening edge side. The first outer side wall 72 is provided with two outer side engaging recesses 72a that penetrate the first outer side wall 72, and the two outer side engaging recesses 72a are respectively located on both sides of the protruding portion 74 in the direction along the opening edge. Two groove-shaped first mounting portions 75a are provided on both sides of the outer wall surface of the second outer side wall 73 on the side of the front wall 71, and are provided at the central portion on the opening edge side of the outer surface of the first outer side wall 72. The second mounting portion 75b has a groove shape.

As shown in FIGS. 5 and 6, the first outer side wall 72 of the cover member 70 is located outside the first inner side wall 22 of the base member 20 and the holding piece 48 of the diffusing element 40, abutting or approaching the first inner side wall 22 And holding the sheet 48. As shown in FIGS. 1 and 4 to 6, the edge portions on the opening side of the first outer side wall 72 and the second outer side wall 73 of the cover member 70 are disposed to face the flange 24 of the base member 20, and The circumferential surface of the flange 24 of the first outer side wall 72 and the second outer side wall 73 is substantially flush. The protruding portion 74 provided on the first outer side wall 72 and the second outer side wall 73 is inserted into the recess 24a of the flange 24 provided in the first inner side wall 22 and the second inner side wall 23 of the base member 20. As shown in FIG. 7 , the protruding portion 74 of the first outer side wall 72 is provided at a position overlapping the portion of the first outer side wall 72 on the outer side of the holding piece 48 in the direction along the edge portion on the opening side. As shown in FIG. 6, the engagement protrusion 22a provided in the 1st inner side wall 22 of the base element 20 is inserted in the outer side engagement recessed part 72a provided in the 1st outer side wall 72. In the present embodiment, the outer engagement portion is formed by the engagement projection 22a and the outer engagement recess 72a.

Next, an example of the assembly work of the pressure sensor 10 of the present embodiment will be described. First, a circuit board 30 on which the components such as the pressure detecting element 31 and the external connection connector 33 are mounted is stacked on the first inner side wall 22 and the second inner side wall 23 of the base member 20. At this time, as shown in FIG. 5, an O-ring 32 is provided between the introduction portion 31a of the pressure detecting element 31 mounted on the circuit board 30 and the base member 20, and is mounted on the circuit board 30. The front end portion of the external connection connector 33 is engaged with the coupling hole 21b of the base member 20.

Thereafter, the holding piece 48 of the diffusing element 40 is placed in the engaging groove 25 provided on the first inner side wall 22 of the base member 20, and the diffusing element 40 is stacked on the upper surface of the circuit board 30. At this time, as shown in FIG. 5, the holding piece 48 is elastically deformed and opened outward, and the engaging claw 48a of the holding piece 48 is inserted into the engaging recessed portion 25 of the first inner side wall 22 to be engaged. At the same time, the auxiliary engagement claws 25b of the first inner side wall 22 are inserted into the auxiliary engagement recesses 48b of the holding piece 48 to be engaged. Therefore, the diffusion member 40 is fixed to the base member 20, and the circuit board 30 is fixed to the base member 20 in a state of being sandwiched between the base member 20 and the diffusion member 40.

Next, the elastic connector 35 is inserted into the connector insertion hole 42 of the diffusing member 40, and the elastic connector 35 and the diffusing member 40 are in a state where the end of the elastic connector 35 is protruded from the connector insertion hole 42. The liquid crystal display element 50 is laminated on the upper surface of the elastic support portion 43. At this time, the liquid crystal display element 50 is positioned on the diffusion element 40 by bringing the edge of the liquid crystal display element 50 against the inner surface of the support wall 47. A button member 60 is attached to the button mounting portion 46 of the diffusing element 40.

Next, the cover member 70 provided with the transparent cover 71b is placed on the base member 20. The base member 20 is provided with a circuit board 30, a diffusion member 40, and the like. At this time, as shown in FIG. 6, the engagement projection 22a provided in the first inner side wall 22 of the base member 20 is inserted into the outer engagement recess 72a provided in the first outer side wall 72, and is engaged. At the same time, as shown in FIG. 1, the protruding portions 74 provided on the first outer side wall 72 and the second outer side wall 73 are inserted into the recesses 24a provided in the first inner side wall 22 and the second inner side wall 23 of the base member 20. . Thereby, the cover member 70 is attached and fixed to the base member 20.

Further, as shown in FIG. 7, the liquid crystal display element 50 is fixed by being sandwiched between the transparent cover 71b mounted on the cover member 70 and the elastic connector 35 of the diffusing member 40 and the elastic supporting portion 43. And by being clamped between the diffusing element 40 and the cover member 70, the button member 60 is fixed. The assembly of the pressure sensor 10 is completed like this. By inserting the jig such as a screwdriver into the detaching recess 26 provided in the base member 20, the first outer side wall 72 and the second outer side wall 73 are bent, and the cover member 70 can be easily removed.

Further, the pressure sensor 10 of the present embodiment is mounted on a panel or the like as described below. As shown in FIG. 8, the side of the window part 71a of the cover member 70 is set to the surface side, and the pressure sensor 10 is inserted in the mounting opening 80a of the mounting object 80. Then, the first mounting assisting device 81 is attached to the circumferential surface of the portion of the pressure sensor 10 that protrudes from the mounting object 80 toward the front surface side, and the second mounting assisting device 82 is attached to the pressure sensor 10 The circumferential surface that protrudes toward the back side.

The first attachment assisting device 81 is formed in a quadrangular frame shape having a larger outer shape than the pressure sensor 10, and the first attachment projection 81a is attached to both opposite sides of the inner surface side. When the first attachment protrusion 81a is engaged with the first attachment portion 75a of the second outer side wall 73 of the cover member 70 of the pressure sensor 10, the first attachment assisting device 81 is fixed to the pressure sensor. 10 on.

The second attachment assisting device 82 is formed in a quadrangular frame shape having a larger outer shape than the pressure sensor 10, and the second attachment projection 82a is attached to both opposite sides of the inner surface side. When the second attachment protrusion 82a is engaged with the second attachment portion 75b of the first outer side wall 72 of the cover member 70 of the pressure sensor 10, the second attachment assisting device 82 is fixed to the pressure sensor. 10 on.

By attaching the first mounting aid 81 and the second mounting assisting device 82, the pressure sensor 10 is restrained from being detached from the mounting object 80 toward the front side and the back side, and the pressure sensor 10 is fixed. On the installation object 80.

Next, the action of this embodiment will be described. In the pressure sensor 10 of the present embodiment, a holding piece 48 extending toward the side of the base element 20 is provided on the diffusing element 40 disposed on the opposite side of the base member 20 with the circuit board 30 interposed therebetween. Further, by engaging the inner engagement portion (the engagement claw 48a and the engagement recess portion 25a, and the auxiliary engagement claw 25b and the auxiliary engagement concave portion 48b) provided between the holding piece 48 and the base member 20, The diffusion element 40 is fixed to the base member 20, and the circuit board 30 is fixed to the base member 20 in a state of being sandwiched between the base member 20 and the diffusion member 40. Therefore, the base member 20, the circuit board 30, and the diffusion member 40 are stacked in order, and the base member 20 and the diffusion member 40 are engaged by the inner engaging portion, and the circuit can be operated by such a simple action. The plate 30 is fixed to the base member 20.

In the fixing structure, when the holding piece 48 is deformed in the outward opening direction and the amount of deformation exceeds the engaging width of the inner engaging portion, the engagement of the inner engaging portion is released, and the circuit board 30 is released. The base portion 20 is fixed. The engagement width of the inner engagement portion is the width of the portion of the engagement claw 48a that is engaged with the engagement recess 25a and the width of the portion of the auxiliary engagement claw 25b that is locked with the auxiliary engagement recess 48b. sum.

Therefore, by partially positioning the first cover member 70 (the first outer side wall 72) provided on the base member 20 for protecting the circuit board 30 and the like on the outer side of the holding piece 48, it is possible to suppress the holding piece 48 from opening outward. The deformation. Thereby, in the case where the cover member 70 is attached, the engagement of the inner engagement portion becomes difficult to be released. As a result, the fixed structure of the circuit board 30 on the base member 20, the base member 20, the circuit board 30, and the diffusing member 40 are stacked in order, and the base member 20 and the diffusing member 40 are made by the inner engaging portion. The snap fit is a fixed structure that is easy to assemble and is also a stable fixed structure that can withstand the pressure from the fluid being measured.

Next, the effects of the present embodiment will be described. (1) The pressure sensor 10 for detecting the pressure of the fluid to be measured is provided with a base member 20 having a flow guiding port 21a for introducing a fluid to be measured, and a pressure detecting element 31 for detecting the introduction of the fluid introduced from the gas guiding port 21a. The pressure of the fluid is measured; the circuit board 30 is stacked, on the base member 20, the pressure detecting element 31 is mounted on the circuit board 30; and the diffusing element 40 is disposed opposite the base member 20 with the circuit board 30 interposed therebetween On the side, between the diffusing element 40 and the base member 20, the circuit board 30 is clamped. The diffusion member 40 is provided with a holding piece 48 extending toward the side of the base member 20, and an inner engaging portion (the engaging claw 48a and the engaging recess 25a, and the auxiliary card) are provided between the holding piece 48 and the base member 20. The engaging claw 25b and the auxiliary engaging recess 48b) fix the base member 20 and the diffusing member 40 by partially engaging one of the members to the other member. A cover member 70 is attached to the base member 20, and the cover member 70 is disposed outside the inner engagement portion to suppress deformation of the holding piece 48.

According to the above configuration, the assembly work can be easily performed, and in particular, the assembly work for fixing the circuit board 30 to the base member 20 can be performed. (2) The inner engaging portion has the engaging claw 48a and the engaging recess 25a. The engaging claw 48a is provided on the holding piece 48, and protrudes toward the base member 20, and the engaging recess 25a is provided on the base member 20, and the card is engaged. The recessed portion 25a is engaged with the engaging claw 48a. Further, an auxiliary engagement recess 48b is provided on the holding piece 48. The auxiliary engagement recess 48b is open to the base end side of the engaging claw 48a, opens to the base member 20 side, and is inserted into the base member 20. The auxiliary engagement recess 48b is an auxiliary engagement claw 25b.

In the case of the above configuration, in order to release the engagement of the inner engaging portion, it is necessary to deform the holding piece 48 to reach the engaging width of the inner engaging portion, in other words, the engaging recess 48a and the engaging recess. The width of the portion where the 25a is locked is equal to or greater than the width of the portion of the auxiliary engagement claw 25b that is locked with the auxiliary engagement recess 48b. Therefore, it is very difficult to release the engagement of the inner engaging portion.

According to the above configuration, in comparison with the case where only one of the engagement claws 48a and the auxiliary engagement claws 25b is omitted and only one engagement claw is provided, the engagement width of the same degree can be secured by about half of the claw length. Therefore, the inner engaging portion can be provided in a smaller space, thereby increasing the degree of freedom in design of the pressure sensor 10. In particular, it is easy to correspond to the miniaturization of the pressure sensor 10.

(3) The base member 20 is formed in a rectangular box shape having two sets of the first inner side wall 22 and the second inner side wall 23 facing each other, and the inner side engaging portion is provided only on one side wall, that is, the first inner side wall 22 and Hold between sheets 48.

According to the above configuration, by fixing the portion where the inner engaging portion is provided between the first inner side wall 22 of the base member 20 and the holding piece 48, the strength of the fixing structure by the inner engaging portion can be ensured, and Suppress production costs.

(4) A second mounting portion 75b is provided on the first outer side wall 72 of the cover member 70, that is, the wall portion outside the holding piece 48 of the diffusing element 40. The second mounting portion 75b and the pressure sensor 10 are mounted thereon. The second mounting aid 82 used when the object 80 is provided is engaged.

According to the above configuration, the second attachment assisting device 82 is located on the outer side of the first outer side wall 72 of the cover member 70 in a state in which the second attachment assisting device 82 is attached. Therefore, when the holding piece 48 of the diffusing member 40 is intended to be deformed in the outward opening direction, the cover member 70 is hard to be deformed in the same direction. As a result, the effect of suppressing the deformation of the holding piece 48 by the cover member 70 is improved.

(5) An outer engaging portion (an engaging projection 22a and an outer engaging recess 72a) is provided between the base member 20 and the cover member 70, and the outer engaging portion is formed by the one side member and the other side The components are engaged to secure the base member 20 and the cover member 70. The outer fitting portion is provided on the same surface of the base member 20 as the surface on which the inner engaging portion is provided.

According to the above configuration, in the assembly process, when the diffusing element 40 is stacked and the lid member 70 is covered, the inner side engaging portion and the outer side engaging portion are provided, and the operation can be performed on the same side. Carry out the assembly.

(6) A flange 24 is provided on the base member 20, and the flange 24 is disposed to face the edge of the cover member 70 on the side of the base member 20.

According to the above configuration, the flange 24 faces the end portion of the cover member 70, so that the problem that the article is accidentally hooked to the end portion of the cover member 70 and the cover member 70 is dropped from the base member 20 is less likely to occur.

(7) The flange 24 is provided with a detaching recess 26, and when the cover member 70 is to be removed from the base member 20, the jig is inserted into the detaching recess 26.

According to the above configuration, in order to improve the strength of the fixing structure by the inner engaging portion, the cover member 70 can be firmly fixed to the base member 20, and the cover can be easily removed from the base member 20 by using the jig. Element 70 is removed. Further, the disassembling portion is provided as a concave portion, and it is difficult to cause the article to be accidentally hooked to the dismounting portion to cause the cover member 70 to fall from the base member 20.

(8) The edge portion on the opening side of the first outer side wall 72 is provided with a pedestal at a position overlapping the portion of the first outer side wall 72 located outside the holding piece 48 in the direction of the same edge portion. A projection 74 projecting from the side of the element 20.

According to the above configuration, the distance from the portion overlapping the holding piece 48 to the edge portion of the cover member 70 becomes long. Therefore, when the holding piece 48 is intended to be deformed in the outward opening direction, the first outer side wall 72 is hardly deformed in the same direction. As a result, the effect of suppressing deformation of the holding piece 48 by the cover member 70 is improved.

(9) The diffusing element 40 used on the pressure sensor 10 having the liquid crystal display element 50 is used as a fixed component.

According to the above configuration, the increase in the number of parts can be suppressed. Further, the above embodiment can be modified and embodied as described below.

The specific configuration of the inner engaging portion is not limited to the above embodiment. For example, the auxiliary engagement claws 25b and the auxiliary engagement recesses 48b may be omitted, or the engagement claws 48a and the engagement recesses 25a may be omitted. Further, instead of the configuration in which the claw and the recess are engaged, the claws may be engaged with each other.

・ The length of the claw of the engaging claw 48a can be set as appropriate. From the viewpoint of ensuring a large engagement width of the inner engagement portion, the length is set such that the front end of the claw of the engagement claw 48a (the front end in the protruding direction) and the first portion of the base member 20 are set at the time of engagement The positions of the inner surfaces of the inner side walls 22 are identical. Further, from the viewpoint of miniaturization, the length is equal to or less than the length: the end of the claw of the engaging claw 48a (the tip end in the protruding direction) and the inside of the first inner side wall 22 of the base member 20 at the time of the engagement The position of the surface is the same. The engaging recess 25a that engages with the engaging claw 48a does not require a through hole. At this point, the same applies to the auxiliary engaging claws 25b.

The holding piece 48 may be provided on the peripheral edge of the base member 20 on the side of the second inner side wall 23 of the diffusing element 40, and the inner side of the base member 20 may be provided between the second inner side wall 23 and the inner side wall 23 of the base member 20. Engagement department.

The holding piece 48 (holding portion) provided in the diffusing element 40 is not limited to a sheet shape. For example, it may be a wall that is erected along some or all of the sides of the diffusing element 40.

In the above embodiment, the holding piece 48 provided on the diffusing element 40 is located outside the first inner side wall 22 of the base element 20, but may be located inside the first inner side wall 22. In this case, the cover member 70 suppresses deformation of the first inner side wall 22 in the outward opening direction.

・ The diffusing element 40 used in the pressure sensor 10 including the liquid crystal display element 50 is used as a fixed component, but an inner engaging portion may be provided between the base member 20 and the base member 20 in addition to the diffusing member 40. Fixed parts.

・ The outer side engagement portion provided between the base member 20 and the cover member 70 may be provided on a surface of the base member 20 that is different from the surface on which the inner engagement portion is provided. In this case, in order to release the deformation direction of the cover member 70 required for the engagement of the outer engagement portion and the deformation direction of the diffusion member 40 required to release the engagement of the inner engagement portion (the deformation direction of the holding piece 48) The force in the direction in which the engagement of the inner engagement portion is released does not become a force that cancels the direction in which the outer engagement portion is engaged. Therefore, the fixing structure becomes more stable by the engagement of the inner engaging portions.

・ The outer engagement portion provided between the base member 20 and the cover member 70 can be omitted. For example, the base member 20 may be configured by a plurality of divided bodies that form a housing space therein, and the divided bodies may be engaged with each other.

・ In the cover member 70, the positions at which the first mounting portion 75a and the second mounting portion 75b are provided may be changed. Among the first mounting portion 75a and the second mounting portion 75b, at least one of the first outer side walls 72 of the cover member 70 (the wall portion on the outer side of the holding piece 48 of the diffusing element 40) is mounted. In the state in which the first attachment assisting device 81 or the second attachment assisting device 82 is attached, the effect of suppressing deformation of the holding piece 48 by the cover member 70 can be enhanced. In addition, from the viewpoint of the remarkable effect, the first attachment portion 75a and the second attachment portion 75b are provided on a portion of the first outer side wall 72 that is located on the outer side of the holding piece 48 or a portion closer to the opening side than the portion. .

・ A base member 20 made of metal may be used instead of the base member 20 made of synthetic resin. In this case, an insulating member is disposed between the base member 20 and the circuit board 30.

The above embodiment is embodied as a pressure sensor 10 including a liquid crystal display element 50, and may be a pressure sensor 10 having no liquid crystal display element 50. In this case, instead of the diffusing element 40, a fixing member forming the inner engaging portion is provided between the base members 20.

10‧‧‧ Pressure sensor
20‧‧‧Base components (frame)
21‧‧‧ Back wall
21a‧‧‧Inlet
21b‧‧‧Link hole
22‧‧‧1st inner side wall
22a‧‧‧Snap protrusion
23‧‧‧2nd inner side wall
24‧‧‧Flange
24a‧‧‧ recess
25‧‧‧ snap groove
25a‧‧‧Clamping recess
25b‧‧‧Auxiliary Card Claw
26‧‧‧Removing recess
30‧‧‧ boards
30a‧‧‧ recess
31‧‧‧ Pressure sensing element
31a‧‧‧Importing Department
32‧‧‧O-ring
33‧‧‧Connector for external connection
34‧‧‧Lighting elements
35‧‧‧Flexible connector
40‧‧‧Diffuser
41‧‧‧Diffuse opening
41a, 41b‧‧‧ long side
42‧‧‧Connector insertion hole
43‧‧‧Elastic support
43a‧‧‧protrusion
44‧‧‧ gap
45‧‧‧ section of the section
46‧‧‧Button Installation Department
47‧‧‧Support wall
48‧‧‧ Keeping the film
48a‧‧‧Card claws
48b‧‧‧Auxiliary snap recess
50‧‧‧Liquid display components
60‧‧‧ button components
70‧‧‧ cover components
71‧‧‧ front wall
71a‧‧‧Window Department
71b‧‧‧clear cover
71c‧‧‧ button opening
72‧‧‧1st outer side wall
72a‧‧‧Pocket recess
73‧‧‧2nd outer side wall
74‧‧‧Protruding
75a‧‧‧1st installation department
75b‧‧‧2nd Installation Department
80‧‧‧Installation objects
80a‧‧‧Installation
81‧‧‧1st installed aid
81a‧‧‧1st Installation Department
82‧‧‧Second installation aids
82a‧‧‧2nd Installation Department

Figure 1 shows an oblique view of the pressure sensor. Figure 2 shows an exploded perspective view of a portion of the pressure sensor (base member, board and diffuser). Figure 3 shows a perspective view of a portion of the pressure sensor (base member, board, and diffuser). Figure 4 shows an exploded perspective view of the pressure sensor. Figure 5 is a cross-sectional view taken along line 5-5 of Figure 1. Figure 6 is a cross-sectional view taken along line 6-6 of Figure 1. Figure 7 is a cross-sectional view taken along line 7-7 of Figure 1. Figure 8 shows an illustration of the installation of the pressure sensor.

20‧‧‧Base components

21a‧‧‧Inlet

22‧‧‧1st inner side wall

24‧‧‧Flange

24a‧‧‧ recess

25‧‧‧ snap groove

25a‧‧‧Clamping recess

25b‧‧‧Auxiliary Card Claw

30‧‧‧ boards

30a‧‧‧ recess

31‧‧‧ Pressure sensing element

31a‧‧‧Importing Department

32‧‧‧O-ring

40‧‧‧Diffuser

41‧‧‧Diffuse opening

47‧‧‧Support wall

48‧‧‧ Keeping the film

48a‧‧‧Card claws

48b‧‧‧Auxiliary snap recess

50‧‧‧Liquid display components

70‧‧‧ cover components

71‧‧‧ front wall

71a‧‧‧Window Department

71b‧‧‧clear cover

72‧‧‧1st outer side wall

74‧‧‧Protruding

Claims (10)

A pressure sensor capable of detecting a pressure of a fluid to be measured, comprising: a base member having an introduction portion for introducing a fluid to be measured; and a pressure detecting element for measuring a pressure introduced from the introduction portion Measuring a pressure of the fluid; a circuit board stacked on the base member, wherein the pressure detecting element is mounted on the circuit board; and a fixing component disposed on a side opposite to the base member sandwiching the circuit board The circuit board is sandwiched between the fixing member and the base member, and a holding portion extending toward the base member side is provided on the fixing member, and a gap is provided between the holding portion and the base member. In the inner engaging portion, the inner engaging portion is fixed to the base member and the other member, and the base member and the fixing member are fixed to each other, and the cover member is attached and fixed to the base member. The cover member is disposed outside the inner engagement portion to suppress deformation of a portion where the inner engagement portion is provided, and the inner engagement portion is provided with a snap fit And the engaging recessed portion, wherein the engaging claw is provided in the holding portion, and protrudes toward the base member side, wherein the engaging recessed portion is provided in the base member, and is engaged with the engaging claw, and the holding portion is provided with an auxiliary engaging portion a concave portion, the auxiliary engagement concave portion is adjacent to a proximal end side of the engagement claw, and is open to the base member side, and the base member is provided with an auxiliary engagement claw, and the auxiliary engagement claw is inserted into the auxiliary engagement concave portion . A pressure sensor capable of detecting a pressure of a fluid to be measured, comprising: a base member having an introduction portion for introducing a fluid to be measured; and a pressure detecting element for measuring a pressure introduced from the introduction portion Measuring the pressure of the fluid; a circuit board stacked on the base member, wherein the pressure detecting element is mounted on the circuit board; and a fixing member disposed on a side opposite to the base member sandwiching the circuit board, the fixed part and the aforementioned The circuit board is sandwiched between the base members, and the fixing member is provided with a holding portion extending toward the base member side, and an inner engaging portion is provided between the holding portion and the base member. The inner engaging portion fixes the base member and the fixing member by engaging a portion of the one side member with the other member, and the cover member is attached and fixed to the base member, and the cover member is disposed. The outer side of the inner engaging portion is configured to suppress deformation of a portion where the inner engaging portion is provided, and the cover member is provided with a mounting portion for fixing the auxiliary device, and the mounting aid is for The pressure sensor is mounted to the installation object. The pressure sensor according to claim 2, wherein the mounting portion is provided on a wall portion of the cover member located outside the inner engaging portion. The pressure sensor according to any one of claims 1 to 3, wherein an outer engagement portion is provided between the base member and the cover member, and the outer engagement portion is The base member and the cover member are fixed by engaging a portion of one of the components on the one side with the other component, and the external engagement portion is provided in the base member and the inner engagement portion. The same surface. A pressure sensor capable of detecting a pressure of a fluid to be measured, comprising: a base member having an introduction portion for introducing a fluid to be measured; and a pressure detecting element for measuring a pressure introduced from the introduction portion Measuring the pressure of the fluid; a circuit board stacked on the base member, wherein the pressure detecting element is mounted on the circuit board; and a fixing member disposed on a side opposite to the base member sandwiching the circuit board, the fixed part and the aforementioned The circuit board is sandwiched between the base members, and the fixing member is provided with a holding portion extending toward the base member side, and an inner engaging portion is provided between the holding portion and the base member. The inner engaging portion fixes the base member and the fixing member by engaging a portion of the one side member with the other member, and the cover member is attached and fixed to the base member, and the cover member is disposed. The outer side of the inner engaging portion is configured to suppress deformation of a portion where the inner engaging portion is provided, and an outer engaging portion is provided between the base member and the cover member, and the outer engaging portion is provided on one side The part of the part is engaged with the part on the other side to fix the base element and the cover element, and the external engagement part is disposed on the base element Setting the same face of the inner surface of the engaging portion. The pressure sensor according to any one of claims 1 to 3, wherein the base member is provided with a flange, and the flange is located on the base member side of the cover member The position of the opposite edge of the edge. A pressure sensor capable of detecting a pressure of a fluid to be measured, comprising: a base member having an introduction portion for introducing a fluid to be measured; and a pressure detecting element for measuring a pressure introduced from the introduction portion Measuring the pressure of the fluid; the circuit board is stacked on the base member, and the pressure detecting element is mounted on the circuit board; and The fixing component is disposed on a side opposite to the base member with the circuit board interposed therebetween, and the circuit board is sandwiched between the fixing component and the base component, and the fixing component is provided with the foregoing A holding portion extending on the side of the base member is provided with an inner engagement portion between the holding portion and the base member, and the inner engagement portion is engaged with a member on the other side by a part of the one side member. Thereby, the base member and the fixing member are fixed, and a cover member is attached and fixed to the base member, and the cover member is disposed outside the inner engagement portion to suppress deformation of a portion where the inner engagement portion is provided. The base member is provided with a flange, and the flange is located at a position facing an edge portion of the cover member on the base member side. The pressure sensor according to claim 6 or 7, wherein the flange is provided with a detaching recess, and when the cover member is to be removed from the base member, the fixture is The aforementioned recess for disassembly is inserted. The pressure sensor according to any one of the preceding claims, wherein the edge portion of the cover member on the side of the base member is in a direction along the edge portion. A protruding portion that protrudes toward the base member side is provided at a position where the cover member overlaps a portion located outside the inner engaging portion. A pressure sensor capable of detecting a pressure of a fluid to be measured, comprising: a base member having an introduction portion for introducing a fluid to be measured; and a pressure detecting element for measuring a pressure introduced from the introduction portion Measuring a pressure of the fluid; a circuit board stacked on the base member, wherein the pressure detecting element is mounted on the circuit board; and a fixing component disposed on a side opposite to the base member sandwiching the circuit board Holding the aforementioned circuit board between the aforementioned fixing member and the aforementioned base member, The fixing member is provided with a holding portion extending toward the base member side, and an inner engagement portion is provided between the holding portion and the base member, and the inner engagement portion is formed by one side member The base member and the other side member are engaged with each other to fix the base member and the fixing member, and a cover member is attached and fixed to the base member, and the cover member is disposed outside the inner engagement portion, and the installation is suppressed. The deformation of the portion of the inner engagement portion on the side of the base member side of the cover member is in a direction along the edge portion of the cover member and the outer portion of the inner engagement portion The overlapping position is provided with a protruding portion that protrudes toward the side of the base member.