JP2661643B2 - Pressure sensor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure sensor having a capacitive pressure transducer, and more particularly, to a pressure sensor suitable for connection between an electric circuit and an electric connector and connection between an electric circuit and a pressure transducer. It is.

[0002]

2. Description of the Related Art FIG. 7 is a sectional view of a conventional pressure sensor, in which a capacitive pressure transducer 2, a hollow support member 5 for holding the pressure transducer 2, and a support member 5 are provided.
An electric circuit 4 using an electric circuit board 3 supported at a predetermined interval between the pressure transducer 2 and a cup-shaped electric circuit having a plurality of connector terminals 6 coupled to the electric circuit 4. And a connector 7.

The electric circuit 4 has an electric circuit board 3 having electronic components mounted on both sides. The circuit board 3 and a plurality of connector terminals 6 projecting into an electric connector 7 are connected to the connector 8 of the circuit board 3. It is electrically connected via a terminal protrusion 6a which can be inserted and removed.

The electric circuit 4 (electric circuit board 3)
The pressure transducer 2 and the pressure transducer 2 are electrically connected by metal terminals 9 and 10 which are disposed on a side 2a opposite to the pressure receiving surface of the pressure transducer 2 and project vertically from the opposite side.

[0005]

In the prior art pressure sensor, a connector terminal 6 provided on an electric connector 7 and the electric circuit 4 are electrically connected via a terminal protrusion 6a capable of fitting and removing. Therefore, the electric circuit 4 and the electric connector 7 can be handled as independent components, and there is an advantage that the assembly workability is simplified in production.

However, in the mass production assembling process, the projecting portion 6 integrated with the connector terminal 6 for transferring signals to the outside is provided.
In the case where a is bent or has a dimensional variation, the terminal protruding portion 6a has a drawback that it may not be properly fitted to the connector 8.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned drawbacks of the prior art. It is an object of the present invention to provide a pressure sensor which can be assembled inexpensively and reliably by improving the structure of the pressure sensor. Is to do.

[0008]

SUMMARY OF THE INVENTION The present invention comprises a housing having a pressure inlet, a capacitive pressure transducer disposed within the housing, and fixed within the housing at a predetermined distance from the pressure transducer. An electric circuit using an electric circuit board having electronic components mounted on both sides thereof, a hollow support member for supporting the electric circuit board, and a cup-shaped housing including the support member and the circuit board and being coupled to the housing. A pressure sensor comprising: an electrical connector; a plurality of connector terminals through which the electrical connector penetrates a main body and is electrically coupled to the circuit board; a flange portion including the circuit board and a support member; A recess cut out to the transducer terminal connection position of the circuit board on the circumference of the portion, and a plurality of cranks of the pressure transducer bent in the recess. Metal terminals fitted, characterized in that is electrically coupled to the electric circuit.

[0009]

A plurality of metal terminals coming out of the pressure transducer are formed in a crank shape, and are fitted into concave portions cut out on the circumference of a flange portion of the electric connector to be connected to the electric circuit board, so that the crank terminals are formed. The bent metal terminal absorbs the dimensional variation that occurs at the time of assembling with the electrical connector or the electric circuit board, and is easily fitted, so that a fitting error relating to the assembling is avoided.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a plan view of a pressure sensor 11 of the present invention.
FIG. 2 shows a front view of the external appearance, and FIG.
Is shown in

In the housing 12, a flat disk-shaped diaphragm 15 of a capacitive pressure transducer 14 which receives pressure through a pressure inlet 13 is hermetically sealed with a gasket 16 or the like. On the opposite side, a circuit board 23 having an electric circuit 22 included in the flange portion 18b of the electric connector 18 and a hollow support member 17 supporting the circuit board 23 are arranged so as to overlap the pressure transducer 14. , The housing 12
Are fixed by caulking or the like.

The pressure transducer 14 has a diaphragm 15 made of a ceramic material such as alumina, and the diaphragm 15 is opposed to a ceramic base 19 at a predetermined distance by a glass sealing material or the like. A capacitor having a capacitance that changes according to the applied pressure is formed by metal coating on the opposing surface of the diaphragm 15 and the ceramic base 19.

The electrical connector 18 has a plurality of connector terminals 24, 25, 26 which penetrate the main body and are electrically connected to the circuit board 23, and a flange portion 18b containing the circuit board 23 and the support member 17. On the circumference of the flange portion 18b, there is provided a concave portion 18c as shown in FIG.

The electrical connection between the pressure transducer 14 and the electric circuit 22 according to the present invention is performed by soldering. In the embodiment shown in FIG. 3, the output of the pressure transducer 14 passes through the ceramic base 19 and from the opposite side 19a to the metal terminal 20,
Withdrawn through 21. The metal terminals 20, 21
Is bent into a crank shape as shown in FIGS. 4 and 5 so as to protrude to the outer peripheral side of the pressure transducer 14, and is fitted into the circumferential concave portion 18c of the flange portion 18b to be connected to the circuit board 23. Is configured. The connection between the metal terminals 20, 21 and the electric circuit board 23 is securely fixed by soldering from one side surface of the cutout portion 18c using a soldering device such as a light beam or a heater.

The circuit board 23 has a hollow cylindrical support member 17 made of an electrically insulating material such as polybutylene terephthalate or the like, and is positioned at a predetermined distance from the pressure transducer 14 so as to be positioned. The circuit board 23 includes an electric circuit 22 that outputs an electric signal corresponding to the pressure applied to the capacitive pressure transducer 14.

The electric circuit 22 is disclosed in, for example, Japanese Patent Laid-Open No. 2-78.
Although the detailed description is omitted because it is disclosed in Japanese Patent Application Laid-Open No. 912, it is noted that it has circuit components such as an integrated circuit unit, a resistor, and a capacitor. In this embodiment,
The electric circuit 22 has an electric circuit board 23 having through holes on both sides made of a ceramic material having good heat resistance and humidity resistance.

The electric connector 18 is formed of an electrically insulating material such as polybutylene terephthalate reinforced with glass, and is arranged in a superposed relation with the support member 17 included therein. The electric connector 18 has a cup shape, and has a plurality of connector terminals 24, 25, and 26 for transmitting and receiving signals to the outside, and a connector for covering / connecting the connector terminals 24-26. A guide cylinder 18a, a projection 18d for preventing a connector coupled with the guide cylinder 18a from coming off, and an inner cylinder 27 engaged with the projection 18d and fitted inside the guide cylinder 18a. And a flange portion 18b including the support member 17 and the electric circuit 22 and integrally extending to a position overlapping the opposite side surface 19a of the pressure transducer 14. The electric circuit 2 is stored in the internal vacancies 28 and 29 defined by the circuit board 23 of the connector 18.
2 electrical components are mounted.

The connector terminals 24, 25, and 26 extend through the body of the electrical connector 18 to one surface 23a of the circuit board 23, and are connected to the circuit board 23 stably fixed in the flange portion 18b. They are electrically connected by soldering or the like. Further, the flange portion 18 of the connector 18
b, an annular groove is provided on the outer periphery thereof.
Is inserted as shown in FIG.
In this way, it is possible to prevent moisture and harmful dust from entering from the caulking portion a.

The pressure sensor according to the present invention is not limited to the above-described embodiment, and may employ a pressure transducer 14 as shown in FIG. 6, for example. The pressure transducer 14 is provided with a notch 19c in the axial direction on the outer peripheral wall 19b of the ceramic base 19, and the metal terminals 20, 21 bent in a crank shape are provided in the notch 19c.
The metal terminals 20 and 21 are fixed so as to protrude from the side surface 19a opposite to the side 5 so that the protruding portions of the metal terminals 20 and 21 are connected to the electric circuit board 23, whereby the same effect as in the above embodiment can be obtained.

Since the pressure sensor according to the present invention is capacitive, the adjustment of the electric circuit 22 to the pressure transducer 14 needs to be performed after mounting on the housing 12 in order to avoid the influence of an external electric field or stray capacitance. 1 and 3
As shown in FIG. 3, the electric connector 18 is provided with a plurality of adjusting holes 31 and 32 penetrating from the inner bottom surface 18e of the guide tube portion 18a to the opposite surface 18f, and a rotary driver or the like inserted from the outside through the adjusting holes 31 and 32. Is used to adjust the trimmer capacitor 33 of the electric circuit 22.

When the adjustment of the trimmer capacitor 33 is completed, a rubber stopper 34 integrally formed with a bellows-like packing is inserted into the adjustment holes 31 and 32 to prevent moisture from entering from outside.
Are inserted so as to seal the openings of the adjustment holes 31 and 32.

[0022]

The gist of the pressure sensor of the present invention has the features described in the claims. Therefore, particularly in the assembly process of mass production, the pressure sensor and the electric circuit which are disadvantageous in the prior art are used. There are no fitting errors of the pressure transducer, the assembly can be easily and reliably performed by the automatic assembling apparatus, and excellent effects such as improvement in quality can be obtained.

[Brief description of the drawings]

FIG. 1 is a plan view of a pressure sensor according to an embodiment of the present invention.

FIG. 2 is an external front view of the pressure sensor.

FIG. 3 is a longitudinal sectional view taken along line AA ′ of FIG. 1;

FIG. 4 is an exploded perspective view of a main part of the pressure sensor.

FIG. 5 is a perspective view of the pressure transducer shown in FIG. 4 as viewed from another angle.

FIG. 6 is an external perspective view showing a modified example of the pressure transducer.

FIG. 7 is a longitudinal sectional view showing a conventional pressure sensor.

[Explanation of symbols]

12 housing, 13 pressure inlet, 14 capacitive pressure transducer, 15 diaphragm, 18 electrical connector,
18c: recess, 20, 21: metal terminal, 22: electric circuit, 23: electric circuit board, 24, 25, 26: connector terminal.

Claims (2)

(57) [Claims] 1. A housing having a pressure inlet, a capacitive pressure transducer disposed in the housing, and electronic components mounted on both surfaces fixed in the housing at a predetermined distance from the pressure transducer. A pressure circuit comprising: an electric circuit using the mounted electric circuit board; a hollow support member that supports the electric circuit board; and a cup-shaped electric connector that includes the support member and the circuit board and is coupled to the housing. In the sensor, a plurality of connector terminals through which the electrical connector penetrates the main body and is electrically coupled to the circuit board; a flange portion including the circuit board and the support member; and a circuit on a circumference of the flange portion. A recess cut out to the transducer terminal connection position of the substrate, and a plurality of metal terminals bent into a crank shape of the pressure transducer are fitted into the recess, and A pressure sensor characterized by being electrically coupled to an electric circuit. 2. The pressure transducer has a notch in an axial direction of an outer peripheral wall surface, and a metal terminal bent in a crank shape is fixed to the notch so as to protrude to a side opposite to the diaphragm. 2. The structure according to claim 1, wherein the protrusion of the metal terminal is connected to the circuit board.
A pressure sensor as described.