JP2540967Y2 - Pressure sensor - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a pressure sensor having a capacitive pressure transducer,

[0002] The present invention relates to a pressure sensor having a capacitive pressure transducer having an electric circuit that can be adjusted after being connected to an electric circuit, improved in assemblability, and mounted on a housing.

[0003]

2. Description of the Related Art Pressure sensors including pressure transducers are known and described, for example, in U.S. Pat. No. 4,875,135. 7A and 7B are cross-sectional views of a conventional pressure sensor. The housing 1 includes a capacitive pressure transducer 2, an electric circuit 3, and a cup-shaped connector body 4 having connector terminals.

The electric circuit 3 has electronic components mounted on a flexible substrate 5, is arranged on the opposite side 2.2 of the converter 2, and is electrically connected to each other and to the converter terminal 6. The opposite end 5.2 of the flexible substrate was bent so as to lie below the bottom of the connector body in the chamber 7, and was electrically connected to the connector terminal 8, and an electronic component was mounted.

[0005] The sensor also has an opening 9 at one end outside the housing of the connector to enable calibration of the electrical circuit 3 to the transducer 2 after mounting on the sensor housing 1. After adjustment with a probe through the opening 9, only the tubular portion was sealed with a rubber material or the like.

[0006]

The prior art pressure sensor has a structure in which a flexible board is bent to be connected to a connector terminal and fixed to the connector terminal. Therefore, the terminal 8 in the connector body 4 and the flexible board 5 are soldered or the like. However, there is a disadvantage in the production work that the fixing work has to be performed. Further, since the sensor is properly calibrated and the sensor is sealed after the calibration, there is also a disadvantage in the production operation that a sealing agent encapsulating and curing process cannot be shortened. In addition, since the hole for calibrating the electric signal is provided outside the housing of the connector, when the sealed portion is used for an automobile, which is a main use, adverse effects such as ambient temperature, humidity, vibration, and oily dust are caused. Had been exposed to For this reason, there has been a drawback that the operation of the electric circuit is disadvantageously caused due to deterioration of the sealant over time and the like.

[0007] The purpose of the present invention is to overcome those disadvantages in the prior art. More specifically, it is an object of the present invention to improve the structure of the pressure sensor, thereby simplifying the assembling work, reducing the cost, and obtaining a pressure sensor with improved quality due to improved environmental resistance.

[0008]

In order to achieve the above object, a pressure sensor according to the present invention comprises a housing having a pressure fluid inlet, a pressure sensing element disposed in the housing, and an electric circuit having electric components mounted on both sides. An electric circuit having a board, and an electric connector body disposed and fixed on an upper portion of the housing, wherein the pressure sensing element is supported at a lower portion in the housing, and an electric circuit is provided between the pressure sensing element and the electric circuit board. A hollow support member made of an insulating material is disposed, a flange portion of the electric connector body is disposed on an upper surface of the electric circuit board, and the hollow support member is interposed between the housing and the electric connector to perform pressure sensing. The device and the electric circuit board are sandwiched and held, and a connector terminal is supported on a bottom surface in the guide cylinder of the electric connector body, and the connector terminal is connected to the electric circuit board. Hamada' capable connected by electric contact, it is characterized in that an adjusting hole for adjusting the electrical circuit signals of the electric circuit on the bottom surface within the guide tube.

[0009]

[0010] Thus, the electric circuit integrated with the converter and the electric connector can be handled as independent parts, and there is an advantage that the assembling work is simplified in production.

Further, according to the present invention, the connector terminal in the housing cylinder of the electric connector is provided with an adjustment hole for an electric signal of an electric circuit on the bottom surface which is drawn out to protect the adjustment hole from a surrounding bad environment during use. At the same time, there is an advantage that the sealing of the adjustment hole can be simplified with a rubber stopper or the like.

[0012]

Since the present invention has the above means,
Due to the change in the pressure of the fluid applied to the pressure fluid inlet, the capacitive pressure transducer changes its capacity and transmits it to an electric circuit, which generates an electric signal corresponding to the changed pressure and controls, for example, a compressor.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings.
FIG. 1 is a plan view of the pressure sensor 11 of the present invention, and FIG.
, And sectional views of the sensor are shown in FIGS. A diaphragm 15 of a flat disk-shaped capacitive pressure transducer 14 which receives pressure through a pressure inlet 13 is hermetically sealed with a gasket 16 or the like in a housing 12, and a support member 17, a flange 18 of a connector body 18. 4 are arranged so as to overlap the transducer 14 and the housing edge 1
2.1 is fixed by caulking or the like.

The pressure transducer 14 has a diaphragm 15 made of a ceramic material such as alumina. The diaphragm 15 is provided at a predetermined distance from the ceramic base 19 with a glass sealing material or the like, and is disposed on the facing surface. Diaphragm 1
A capacitor having a capacitance that changes according to the applied pressure is formed on the facing surface of the ceramic base 19 with the metal coating 5.

The output of the converter 14 is a ceramic base 19
From the opposite side 19. 1 as metal terminals 20, 21 and at predetermined intervals by a hollow disk-shaped support member 17 arranged opposite the opposite side 19.1 of the converter. It is electrically connected to the circuit 22. The support member is formed of an electrically insulating material such as polybutylene terephthalate, and has a groove so that the positions of the converter 14 and the electric circuit 22 are determined. The electrical circuit includes an electrical circuit that outputs an electrical signal corresponding to the pressure applied to the capacitive transducer.

Since this circuit is disclosed in, for example, Japanese Patent Application Laid-Open No. 2-78912, all details of the circuit are not described here, and the circuit has circuit components such as an integrated circuit unit, a resistor, and a capacitor. It is recognized that. In this embodiment, the electric circuit 22 has an electric circuit board 23 having through-holes made of both sides made of a ceramic material having good heat resistance and humidity resistance.

The sensor has a connector body 18 of an electrically insulating material, such as polybutylene terephthalate, reinforced with glass and disposed in an overlying relationship with the support member 17.

The connector body is provided with a connector tubular section 18.1 for fitting and removing the connector, which covers a plurality of connector terminals 24, 25, 26 for transferring signals to the outside, and a convex section 18.2 for preventing the connector from coming off. , 18.3 on the outer periphery and the support member 17.
And a flange portion 18.4 that extends integrally with the electric circuit board 23 so as to overlap.

The electric components of the electric circuit 22 are mounted in the vacant space 27 of the connector body and the hollow portion 28 of the support member 17. According to the present invention, the electrical connection between the electric circuit 22 and the plurality of connector terminals 24, 25, 26 is performed by a connector that can be fitted and removed.

In the embodiment shown in FIGS. 3 and 4, the connector terminals 24, 25, and 26 connected to the electric circuit are in the form of circular or flat convex pins.
Is configured to be coupled to the concave connectors 29, 30, and 31 mounted on the connector. The connectors may be arranged independently of each other as shown in the figure, or may be arranged at one location. In the embodiment shown in FIG. 5, a plate-like lever 32 made of beryllium copper having spring properties and connected to the connector terminal by caulking or the like is provided on one surface of the electric circuit board.
It is bent so as to be parallel to 1 and has a conical-convex electric contact 33 at the tip, and is joined to a metal foil electrode provided on the electric circuit board 23. In addition, in the case of this configuration, preferably, the electrical contact 33 and the metal foil electrode are provided with a surface bead such as a gold plating to improve the contact reliability. In the embodiment shown in FIG. 6, a lever 34 connected to a connector terminal by caulking or the like and having a constricted portion with a resilient end is provided with a hole 1 provided in the support member 17.
7.1, the contact 35 protruding from the electric circuit board 23
Are electrically connected by insertion.

According to the present invention, since the sensor is capacitive, the adjustment of the electric circuit 22 to the converter 14 needs to be performed after the sensor 12 is mounted on the housing 12 in order to avoid the influence of an external electric field and stray capacitance. Therefore, as shown in FIGS. 3 and 4, a plurality of adjusting holes 36 extend from the protruding surface 18.5 of the plurality of connector terminals 24, 25, 26 extending to a position outside the connector body 18 to the inner opposite surface 18.6. , 37. In this arrangement, the semi-fixed regulators 38 and 39 of the electric circuit 22 are inserted through adjustment holes 36 and 37 from outside to insert a rotary driver (not shown), and the electric circuit 22 is adjusted in a known manner. ing. At least two locations need to be adjusted to determine the relationship between pressure and output voltage. In addition, since this adjustment operation is performed while applying pressure, the connector terminals 41, 25 fitted to the connector terminals 24, 25, 26 in the housing 40A of the external coupler 40 coupled to the connector body of the sensor 11.
42 and 43 and a driver insertion port are formed.

Further, depending on the configuration of the electric circuit 22, there may be a case where the calibration is performed by external electric calibration instead of mechanical adjustment. Even in such a case, it is possible to perform calibration in a known manner by inserting an electric contact probe into the adjustment hole.

Further, depending on the configuration of the electric circuit 22, trimming by a laser beam may be performed from outside without mechanical adjustment. Even in such a case, it is possible to arrange the shape and layout of the adjustment holes as in the case described above. When the adjustment is completed, the adjustment hole has a stopper projection and can be plugged into a plurality of adjustment holes.
4 is configured to be inserted and sealed. Or even
As shown in FIG. 5, the adjusting hole may be configured to be covered with a lid 45 and then sealed with a sealant 46 such as a rubber material.

[0024]

According to the structure of the present invention, the soldering work required for the electrical connection between the electric circuit and the connector terminal, which is a disadvantage of the prior art, is unnecessary in the assembly process of mass production, and the automatic assembling apparatus is used. Is configured to be easily and securely fixedly connected.

Also, a hollow support member made of an electrically insulating material is disposed in the housing, and the support member is interposed between the housing and the connector so that the pressure sensing element is formed between the housing and the connector. The pressure sensing element and the electric circuit board are electrically insulated from each other and held firmly at predetermined intervals without causing distortion or the like during assembly. Further, since an adjustment hole for adjusting an electric circuit signal of the electric circuit is formed in the guide cylinder of the connector body, FIG.
As shown in the above, when the pressure sensor is used, the guide hole is covered by the housing of the external coupler 40 or the bushings 47, 48, 49, etc., so that the adjustment hole is blocked from the outside, and the adjustment hole is closed. Ambient temperature, humidity,
The quality can be improved without being exposed to the adverse effects of vibration, oily dust, and the like.

[Brief description of the drawings]

FIG. 1 is a plan view of a sensor of the present invention.

FIG. 2 is an external view of the sensor of the present invention.

FIG. 3 is a sectional view taken along line 3-3 in FIG. 1;

FIG. 4 is a sectional view taken along the line 4-4 in FIG. 1;

FIG. 5 is a sectional view of a main part of another embodiment of the sensor of the present invention.

FIG. 6 is a sectional view of still another embodiment of the sensor of the present invention.

FIG. 7 is a cross-sectional view of a conventional sensor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 12 Housing 13 Pressure flow inlet 14 Pressure sensing element 17 Support member 22 Electric circuit 23 Electric circuit board 24, 25, 26 Connector terminal

 ──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-2-190731 (JP, A) JP-A-59-208432 (JP, A) JP-A-1-300092 (JP, A) JP-A-58-208 198739 (JP, A) JP-A-62-267636 (JP, A) JP-A-2-146731 (JP, U)

Claims (1)

(57) [Scope of request for utility model registration] 1. A housing having a pressure fluid inlet, an electric circuit having a pressure sensing element disposed in the housing and an electric circuit board having electric components mounted on both sides thereof, and an electric connector body disposed and fixed on an upper portion of the housing. A pressure sensor comprising: a pressure sensor that supports the pressure sensing element at a lower portion in the housing;
A hollow support member made of an electrically insulating material is arranged between the pressure sensing element and the electric circuit board, and a flange portion of the electric connector body is arranged on an upper surface of the electric circuit board, and the housing and the electric connector are arranged. While holding and holding the pressure sensing element and the electric circuit board with the hollow support member interposed therebetween, the connector terminal is supported on the bottom surface in the guide cylinder of the electric connector body, and the connector terminal is provided with the connector terminal. A pressure sensor, which is connected to an electric circuit board so as to be detachable by electric contact contact, and has an adjustment hole for adjusting an electric circuit signal of the electric circuit on a bottom surface in the guide cylinder.