JP5500001B2 - Pressure sensor mounting structure - Google Patents

Description

  The present invention relates to a pressure sensor mounting structure.

  Conventionally, pressure sensors as disclosed in Patent Documents 1 and 2 have been known. This pressure sensor has a diaphragm that deforms in response to pressure, and includes a pressure detection unit that converts changes in resistance, capacitance, and the like due to deformation of the diaphragm into electrical signals and outputs them. A signal from the pressure detection unit is taken out through wire bonding, a circuit board, a pin, an FPC (flexible printed circuit) or a lead wire, a connector pin, a bus bar, and the like.

  FIG. 9 is an external view of a pressure sensor according to the prior art. As shown in FIG. 9, the pressure sensor 100 according to the prior art includes a case 101 in which a pressure detection unit and a circuit board are accommodated. The case 101 is integrated with a screw portion 102 for coupling to a body of a device to be detected, a connector 103 for taking out a signal to the outside, and the like. A flange portion may be provided instead of the screw portion 102.

  In the pressure sensor 100, internal parts such as a diaphragm and a circuit board are protected by a case 101, a connector 103, and the like, and a mounting structure with a device to be detected such as a screw or a flange is designated, so that the specifications, usage environment, etc. Can be used in a wide range of various devices.

  A device that uses such a pressure sensor 100 includes a transmission that is a device that is hydraulically controlled in an automobile. A plurality of solenoid valves and pressure sensors are arranged inside a transmission such as an AT (Automatic Transmission) or a CVT (Continuously Variable Transmission). These are controlled by a CU (control unit) that controls the transmission.

  The CU is generally arranged at a location different from the transmission from the transmission via a wire harness. Recently, however, an electromechanically integrated configuration in which the CU is arranged inside the transmission has been proposed. . Since the CU requires a relatively large arrangement space, there is a demand for miniaturization and space saving of solenoid valves and pressure sensors that are also arranged inside the transmission.

  As described above, since the pressure sensor 100 includes the case 101 in which the attachment portion such as the screw portion 102 and the connector 103 are integrated, there is a limit to the installation space that can be reduced. Although there is a configuration in which the mounting portion such as the screw portion 102 is eliminated from the case 101, a space for installing a circuit board containing an amplifier circuit or the like is required in the vicinity of the pressure detection portion. There is a limit.

Japanese Patent No. 3463536 Japanese Patent No. 3815282

The present invention has been made to solve the above-described problems of the prior art, and an object of the present invention is to provide a pressure sensor mounting structure capable of saving space, reducing weight, and reducing costs. It is in.

In order to achieve the above object, the pressure sensor mounting structure in the present invention comprises:
A pressure sensor mounting structure for mounting the pressure sensor to a device to be detected,
A housing space for housing a pressure detection unit having a diaphragm is provided between the housing of the device and another member attached to the outer surface of the housing, and the housing space communicates with the internal space of the housing. A communication hole is provided,
The pressure detection unit is accommodated in the accommodation space so that the pressure-sensitive surface of the diaphragm can receive the pressure inside the housing through the communication hole,
FPC which is a wiring for taking out the output signal of the pressure detection unit to the outside is drawn out from the housing space to the outside of the housing ,
The pressure detector and the FPC are integrally attached to a case member,
The case member is sandwiched and fixed between the housing and the other member in the accommodation space;
The FPC is mounted with a circuit board that includes an amplification circuit that amplifies an output signal of the pressure detection unit and extends from the case member along the attachment surface of the housing and the other member in the accommodation space And
A circuit board with the pressure sensing portion is disposed along said mounting surface and said Rukoto.
In order to achieve the above object, the pressure sensor mounting structure according to the present invention includes:
A pressure sensor mounting structure for mounting the pressure sensor to a device to be detected,
A housing space for housing a pressure detection unit having a diaphragm is provided between the housing of the device and another member attached to the outer surface of the housing, and the housing space communicates with the internal space of the housing. A communication hole is provided,
The pressure detection unit is accommodated in the accommodation space so that the pressure-sensitive surface of the diaphragm can receive the pressure inside the housing through the communication hole,
The wiring for taking out the output signal of the pressure detection unit is drawn out from the housing space to the outside of the housing,
The pressure detection unit and the wiring are integrally attached to a case member,
The case member is sandwiched and fixed between the housing and the other member in the accommodation space;
Mounting including an amplifying circuit for amplifying an output signal of the pressure detection unit on a circuit board that extends in the housing space along a mounting surface between the housing and the other member and has one end fixed to the case member The parts are mounted,
The mounting component and the pressure detection unit are arranged along the mounting surface.

  The pressure sensor does not have a case member or the like for accommodating the pressure detection unit, and the pressure detection unit is provided in an accommodation space provided between a housing to which the pressure sensor is attached and another member attached to the housing. Be contained. That is, instead of providing the pressure sensor with its own case, the housing of the counterpart device and other members attached thereto are used as the case of the pressure sensor. Thereby, the case member unique to the pressure sensor becomes unnecessary, the number of members is reduced, and the space for arranging the pressure sensor can be reduced. Therefore, the number of members in the pressure sensor mounting structure can be reduced, the cost can be reduced, the space can be saved, the overall weight of the counterpart device can be reduced, and the size can be reduced.

  As described above, by integrating the pressure detection unit and the wiring with the case member to form a unit, the mounting operation can be simplified. In addition, the pressure detection unit can be positioned and fixed in the accommodation space by using another member attached to the housing and fixing the case member between the housing and the other member. Thereby, it is not necessary to separately provide a means for fixing the pressure detection unit. Therefore, the components are simplified, and the installation work is facilitated.

A seal member is disposed between the diaphragm and the opening of the communication hole,
When the other member is attached to the housing, the seal member is pressed between the diaphragm and the opening of the communication hole by the case member being pressed against the housing by the other member. It should be compressed.

  In this way, the configuration can be further simplified by enabling the compression state of the seal member to be formed using the pressing force of other members.

An FPC (flexible printed circuit) is a flat conductive member having flexibility and flexibility, and wiring with a high degree of freedom is possible without being restricted by the space of the installation space. The FPC is extended from the case member (pressure detection unit) along the attachment surface between the housing and the other member, and the circuit board and the pressure detection unit are mounted on the FPC in an arrangement along the attachment surface. Thereby, the height of the accommodation space can be kept low.

  As described above, by fixing the circuit board including the amplifier circuit and the like to the case member and integrating the circuit board including the circuit board, the mounting operation can be further facilitated. Moreover, the mounting space of the circuit board and the pressure detection unit are arranged along the attachment surface between the housing and the other member, so that the height of the accommodation space can be suppressed low.

The wiring is
The space between the other member and the housing is pulled out from the housing space, and
A gasket that surrounds the accommodation space and seals between the other member and the housing may be integrally provided at a portion that passes between the other member and the housing.

The wiring is
Through the lead-out hole provided in the housing, it is pulled out from the housing space, and
A grommet that seals a gap between the lead hole and the wiring may be integrally provided.

  Thereby, the storage space is blocked from the outside, the influence of the external environment on the pressure detection unit can be reduced, and the pressure detection unit can be protected.

  According to the present invention, space saving, weight reduction, and cost reduction can be achieved.

It is typical sectional drawing which shows the attachment structure of the pressure sensor which concerns on Example 1 of this invention. It is typical sectional drawing which shows the structure of the pressure sensor which concerns on Example 1 of this invention. It is a typical perspective view when the attachment structure of the pressure sensor of FIG. 1 is seen from the outer surface side of the housing. It is a typical perspective view which shows the attachment surface with the housing in another member. It is typical sectional drawing which shows the attachment structure of the pressure sensor which concerns on Example 2 of this invention. It is a typical perspective view when the attachment structure of the pressure sensor of FIG. 5 is seen from the outer surface side of the housing. It is typical sectional drawing which shows the attachment structure of the pressure sensor which concerns on Example 3 of this invention. It is a typical perspective view when the attachment structure of the pressure sensor of FIG. 7 is seen from the outer surface side of the housing. It is a typical perspective view which shows the external appearance of the pressure sensor which concerns on a prior art.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be exemplarily described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention only to those unless otherwise specified. .

Example 1
With reference to FIGS. 1-4, the attachment structure of the pressure sensor which concerns on Example 1 of this invention is demonstrated. FIG. 1 is a schematic cross-sectional view showing a pressure sensor mounting structure according to Embodiment 1 of the present invention. FIG. 2 is a schematic cross-sectional view illustrating the configuration of the pressure sensor according to the first embodiment of the invention. 3 is a schematic perspective view when the pressure sensor mounting structure of FIG. 1 is viewed from the outer surface side of the housing (the mounting surface side of other members). FIG. 4 is a schematic perspective view showing a mounting surface of another member with the housing.

<Schematic configuration of mounting structure>
As shown in FIG. 1, the pressure sensor mounting structure according to this embodiment is a structure for mounting the pressure sensor 1 to a housing 2 of a device to be detected. On the outer surface 20 of the housing 2, a recess 21 is formed in a region where another member 3 is attached. An accommodation space for accommodating the pressure sensor 1 is formed between the housing 2 and the other member 3 by the recess 21. The recess 21 is closed by attaching another member 3. A communication hole 23 that penetrates the housing 2 (communication between the inside and the outside of the housing 2) is provided on the bottom surface 22 of the recess 21 so that the internal pressure of the housing 2 can be detected.

  In this embodiment, the pressure detection target device is a vehicle transmission that is hydraulically controlled. The other members 3 are a CU 30 and a CU case 31 that control the transmission. However, the mating member to which the pressure sensor is attached is not limited to this. The CU 30 is attached to the upper surface of the CU case 31. The CU case 31 may be attached with wiring for the CU 30 or a heat sink. In addition, a protective cover may be attached.

<Configuration of pressure sensor>
As shown in FIG. 2, the pressure sensor 1 includes a pressure detection unit 12 including a diaphragm 10 and a strain gauge 11. The diaphragm 10 has a pressure-sensitive portion 10a formed to be thin. A plurality of strain gauges 11 are arranged on the surface of the pressure-sensitive portion 10a opposite to the pressure-sensitive surface 10b via an insulating layer. Although the specific configuration and pressure detection principle of the pressure detection unit 12 are conventional techniques and detailed description thereof is omitted, the pressure detection unit 12 is deformed by the pressure received by the pressure sensitive surface 10b by the pressure sensitive surface 10b. The deformation of the portion 10a is output as an output change of the strain gauge 11. The diaphragm 10 can be made of various materials such as metal, silicon, and ceramic. In addition to the above-described thin film type, a semiconductor type, a capacitance type, or the like can be used as a pressure detection method. Further, the pressure sensor 1 has an FPC 13 as a wiring for taking out an output signal from the pressure detection unit 12 to the outside.

  As shown in FIG. 1, the pressure sensor 1 includes a unit in which a pressure detection unit 12 and an FPC 13 are integrated by a case member 15. The case member 15 is fixed to the outer periphery of the diaphragm 10 of the pressure detection unit 12. In this embodiment, as shown in FIG. 2, the lower surface of the case member 15 and the upper surface of the flange portion 10c provided at the lower end of the diaphragm 10 are fixed by adhesion or the like. Further, one end side of the FPC 13 is overlapped and fixed on the upper surface of the case member 15. The pressure detector 12 and the FPC 13 are electrically connected by wire bonding 14. The FPC 13 is bonded and fixed to the upper surface of the case member 15 with an adhesive or the like. The FPC 13 is extended from the pressure detection unit 12 substantially along the mounting surface (the outer surface 20 of the housing 2) between the housing 2 and the CU case 31, and passes between the outer surface 20 of the housing 2 and the CU case 31. 2 is pulled out.

  The wire bonding 14 is covered with a potting portion 16 in order to protect it from the external environment. The potting portion 16 is formed by providing a protective plate 16a made of resin so as to cover the outside of the wire bonding 14 on the upper surface of the FPC 13, and a gel-like potting agent is poured into the protective plate 16a.

  The pressure sensor 1 has a circuit board 17. An amplifier circuit for amplifying and outputting the output signal of the strain gauge 11 is mounted on the circuit board 17. The electrical connection between the circuit board 17 and the FPC 13 may be soldered directly or via a pin (not shown) or the like. Moreover, you may connect by welding etc. The circuit board 17 may be mounted directly on the FPC 13 without using a glass epoxy board or the like. When the diaphragm 10 is a silicon diaphragm or the like, an amplifier circuit or the like may be formed directly on the diaphragm.

  In the pressure sensor 1, the pressure detection unit 12 and the circuit board 17 are arranged side by side along the mounting surface of the housing 2 and the CU case 31. When the CU case 31 is attached to the outer surface 20 of the housing 2, the case member 15 of the pressure sensor 1 is pressed against the bottom surface 22 of the recess 21 by the CU case 31. Thereby, the pressure sensor 1 is positioned and fixed in the recess 21. The lower surface 32 of the CU case 31 is provided with a pressing portion 33 for contacting the upper surface of the case member 15 and pressing the case member 15 downward.

  An annular gasket 18 is integrally provided on the FPC 13 by integral molding or the like. The gasket 18 is disposed between the housing 2 and the CU case 31 so as to surround the outer periphery of the recess 21, and seals between the housing 2 and the CU case 31. Thereby, the space between the recess 21 and the CU case 31, that is, the accommodation space of the pressure sensor 1 is sealed from the outside. As shown in FIGS. 3 and 4, in this embodiment, mounting grooves 24 and 34 for mounting the gasket 18 are provided on the outer surface 20 of the housing 2 and the lower surface 32 of the CU case 31 in contact with the outer surface 20. Yes.

  Between the flange portion 10c provided at the lower end of the diaphragm 10 and the opening edge portion of the communication hole 23, a rubber O-ring 4 is disposed as a seal member. The flange portion 10 c is pressed against the bottom surface 22 of the recess 21 when the case member 15 is pressed by the CU case 31. Thereby, the O-ring 4 is compressed between the flange portion 10 c of the diaphragm 10 and the opening edge portion of the communication hole 23, and seals between the flange portion 10 c and the opening edge portion of the communication hole 23.

<Excellent points of this embodiment>
As described above, according to the pressure sensor mounting structure of the present invention, the pressure sensor does not have an original case member or the like as in the prior art, and detects internal components such as a diaphragm, a strain gauge, and an amplifier circuit. It is configured to be directly assembled to the housing of the target device. That is, instead of providing the pressure sensor with its own case, the housing of the counterpart device and other members attached thereto are used as the case of the pressure sensor. Thereby, it can contribute to reduction of the number of parts in the attachment structure of a pressure sensor, cost reduction, space saving, weight reduction, size reduction, etc. of a counterpart device.

  In the pressure sensor, the pressure detection unit and the wiring are unitized, and the unit is positioned and fixed between the housing and the other member by being pressed against the bottom surface of the recess by the other member attached to the housing. Therefore, there is no need to separately provide a fixing means for positioning and fixing the pressure sensor, the components are simplified, and the mounting operation is facilitated.

  Further, since the unit is not completely fixed to the housing or other members by welding, adhesion, fitting, or the like, it is easy to remove.

  Furthermore, since the unit is connected to the housing and other members via a seal member such as an O-ring or gasket, the effect of distortion on the diaphragm caused by the difference in linear expansion coefficient with the housing due to temperature change is reduced. Can do.

  A circuit board including an amplifier circuit and the like is mounted on an FPC extended from the pressure detection unit along the attachment surface between the housing and another member. That is, the pressure detection unit and the circuit board are arranged side by side along the mounting surface (housing outer surface). Thereby, the depth of a recessed part is shallow, ie, the height of the accommodation space of the component of a pressure sensor can be restrained low.

  Further, in the case of a CU for AT or CVT, the CU is larger than the pressure sensor, and the mounting area in the housing is also increased. Therefore, by effectively utilizing the dead space below the CU mounting surface in the housing, the transmission can be reduced in size and space can be saved.

  In this embodiment, the housing space for housing the pressure sensor is formed by providing a recess in the housing. However, the housing may be formed by providing a recess in another member. You may form a recessed part in each.

(Example 2)
With reference to FIG.5 and FIG.6, the attachment structure of the pressure sensor which concerns on Example 2 of this invention is demonstrated. FIG. 5 is a schematic cross-sectional view showing a pressure sensor mounting structure according to the present embodiment. FIG. 6 is a schematic perspective view of the pressure sensor mounting structure of FIG. 5 as viewed from the outer surface side of the housing.

  Here, only the configuration different from the above embodiment will be described. Constituent elements common to the above-described embodiments are denoted by the same reference numerals and detailed description thereof is omitted.

  In the present embodiment, the housing 2 is provided with a communication hole 25 that communicates with the recess 21 and the outside of the housing 2. The FPC 13 extends outside the housing 2 through the communication hole 25, not between the outer surface 20 of the housing 2 and the CU case 31. A gap between the FPC 13 and the communication hole 25 is sealed with a grommet 19. Note that a seal member (not shown) such as a gasket is disposed between the housing 2 and the CU case 31 as necessary for sealing.

(Example 3)
With reference to FIG.7 and FIG.8, the attachment structure of the pressure sensor which concerns on Example 3 of this invention is demonstrated. FIG. 7 is a schematic cross-sectional view showing a pressure sensor mounting structure according to the present embodiment. FIG. 8 is a schematic perspective view when the pressure sensor mounting structure of FIG. 5 is viewed from the outer surface side of the housing.

  Here, only the configuration different from the above embodiment will be described. Constituent elements common to the above-described embodiments are denoted by the same reference numerals and detailed description thereof is omitted.

In this embodiment, the diaphragm 10 and the case member 15 are integrated, and the circuit board 17 ′ is directly integrated with the case member 15. One end of the circuit board 17 ′ is laminated and fixed on the upper surface of the case member 15, and is disposed in the recess 21 so as to extend from the case member 15 along the attachment surface between the housing 2 and the CU case 31. Circuit board 17 'such as an amplifier circuit
The components mounted on are arranged side by side with the pressure detector 12 along the mounting surface.

  The pressure detector 12 is connected to the circuit board 17 ′ by wire bonding 14 ′. Connected to the circuit board 17 ′ is a lead wire 13 ′ for taking out the output signal of the pressure detector 12 to the outside. Note that an FPC may be used instead of the lead wire 13 'as in the above embodiment.

  The housing 2 is provided with a communication hole 25 ′ communicating with the recess 21 and the outside of the housing 2. The lead wire 13 ′ extends to the outside of the housing 2 through the communication hole 25 ′. A gap between the lead wire 13 'and the communication hole 25' is sealed with a grommet 19 '. Note that a seal member (not shown) such as a gasket is disposed between the housing 2 and the CU case 31 as necessary for sealing.

  According to the present embodiment, fixing the circuit board 17 ′ to the case member 15 and integrating them can further facilitate the mounting operation. In addition, by arranging the mounting position of the amplifier circuit or the like side by side with the pressure detection unit 12, the depth of the recess 21 can be made shallow, that is, the height of the accommodation space can be kept low.

DESCRIPTION OF SYMBOLS 1 Pressure sensor 10 Diaphragm 11 Strain gauge 12 Pressure detection part 13 FPC
14 Wire bonding 15 Case member 16 Potting portion 17 Circuit board 18 Gasket 2 Housing 20 Upper surface 21 Recessed portion 22 Bottom surface 23 Communication hole 3 Other member 30 CU
31 CU case 4 O-ring

Claims (5)

A pressure sensor mounting structure for mounting the pressure sensor to a device to be detected,
A housing space for housing a pressure detection unit having a diaphragm is provided between the housing of the device and another member attached to the outer surface of the housing, and the housing space communicates with the internal space of the housing. A communication hole is provided,
The pressure detection unit is accommodated in the accommodation space so that the pressure-sensitive surface of the diaphragm can receive the pressure inside the housing through the communication hole,
FPC which is a wiring for taking out the output signal of the pressure detection unit to the outside is drawn out from the housing space to the outside of the housing ,
The pressure detector and the FPC are integrally attached to a case member,
The case member is sandwiched and fixed between the housing and the other member in the accommodation space;
The FPC is mounted with a circuit board that includes an amplification circuit that amplifies an output signal of the pressure detection unit and extends from the case member along the attachment surface of the housing and the other member in the accommodation space And
Mounting structure of the pressure sensor and the circuit board and the pressure sensing portion is disposed along said mounting surface and said Rukoto. A pressure sensor mounting structure for mounting the pressure sensor to a device to be detected,
A housing space for housing a pressure detection unit having a diaphragm is provided between the housing of the device and another member attached to the outer surface of the housing, and the housing space communicates with the internal space of the housing. A communication hole is provided,
The pressure detection unit is accommodated in the accommodation space so that the pressure-sensitive surface of the diaphragm can receive the pressure inside the housing through the communication hole,
The wiring for taking out the output signal of the pressure detection unit is drawn out from the housing space to the outside of the housing,
The pressure detection unit and the wiring are integrally attached to a case member,
The case member is sandwiched and fixed between the housing and the other member in the accommodation space ;
Mounting including an amplifying circuit for amplifying an output signal of the pressure detection unit on a circuit board that extends in the housing space along a mounting surface between the housing and the other member and has one end fixed to the case member The parts are mounted,
The mounting component and the and the pressure sensing portion is disposed along the mounting surface mounting structure to that pressure sensor, wherein Rukoto. A seal member is disposed between the diaphragm and the opening of the communication hole,
When the other member is attached to the housing, the seal member is pressed between the diaphragm and the opening of the communication hole by the case member being pressed against the housing by the other member. The pressure sensor mounting structure according to claim 1 , wherein the pressure sensor is compressed. The wiring is
The space between the other member and the housing is pulled out from the housing space, and
The gasket which seals between the said other member and the said housing surrounding the said accommodation space in the site | part which passes between the said other member and the said housing is integrally provided from Claim 1 characterized by the above-mentioned. 4. The pressure sensor mounting structure according to any one of 3 above. The wiring is
Through the lead-out hole provided in the housing, it is pulled out from the housing space, and
The pressure sensor mounting structure according to any one of claims 1 to 3 , further comprising a grommet that integrally seals a gap between the lead hole and the wiring.

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