JPH1114485A - Pressure sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure sensor wherein the electric output can be adjusted during manufacture while the size of the entire sensor can be reduced without causing increase in the number of parts. SOLUTION: The pressure sensor 100 comprises an electric circuit board 2, a pressure sensor module 1, a case 4, a housing main body 3 where the substrate 2, the module 1, and the case 4 are housed, and a connector part 5, and the housing main body 3 comprises an internal space 34 where the substrate 2, the module 1 and the case 4 are housed and a rising part 31 which rises around an upper part, and the rising part 31 is divided into a part where a plurality of slits are provided for caulking the case and a part where the connector is caulked, and at the peripheral upper part of the case 4 and the peripheral lower part or the connector part 5, notch parts which engaged each other are provided, and the case 4 is fixed by a case caulking part while the pressure sensor main body and the case are fixed as one body with a connector caulking part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure sensor, and more particularly to a structure of a pressure sensor which has a reduced number of parts, is reduced in size, is easily adjusted, and is easily assembled.

[0002]

2. Description of the Related Art The structure of a conventional pressure sensor 150 will be described with reference to FIG. The conventional pressure sensor 150 includes a pressure sensor module 1 such as a variable capacitance type pressure sensor or a variable resistance type pressure sensor, and an electric circuit that converts a change in capacitance or a change in resistance into a current or voltage electric output. Circuit board 2 on which is mounted
And a case 4 on which the electric circuit board is mounted, and the pressure sensor module 1, the electric circuit board 2, and the case 4
, A housing 5 having a space connected to the pressure measuring space, a connector 5 for taking out the electric circuit output to the outside, a sealing member 6, and a sleeve 9 for fixing the housing body 3 to the connector 5. Consists of

The pressure sensor module 1 includes a substrate 11 made of an insulating material such as ceramic and a pressure responsive plate 12 made of ceramic or the like held at a predetermined interval by an interval holding member 13 made of a glass adhesive or the like. Be composed. When the pressure sensor module 1 is composed of a variable capacitance type pressure sensor element, electrostatic electrodes are respectively provided on opposing surfaces of the substrate 11 and the pressure response plate 12, and an electric signal is externally transmitted by the pins 14. It is configured to take out. When the pressure sensor module 1 is composed of a variable resistance type pressure sensor element, a bridge composed of a resistance pair is provided on a surface of the pressure response plate 12 facing the substrate 11, and an electric signal is taken out by a pin 14. Is configured.

[0004] The electric circuit board 2 is provided with circuit elements 22 such as resistors and arithmetic elements constituting a capacitance-electric signal conversion circuit or a resistance value-electric signal conversion circuit on the upper and lower surfaces of a substrate 21. An electric signal is extracted to the outside by a pin 23 soldered to an electrode pad provided on the upper surface of the substrate 21.

[0005] The case 4 is made of an insulating material and is formed in a cylindrical shape. The electric circuit board 2 is mounted and fixed on a step provided inside.

The housing body 3 includes a body portion 35, a space 34 provided inside the body portion 35, a rising portion 31 rising above the space, and a flange portion 36 provided on the outer periphery of the body portion 35. Is connected to the pressure measurement space by the through hole 33.

The pressure sensor main body is formed by laminating the sealing member 6, the pressure sensor module 1, and the case 4 to which the electric circuit board 2 is fixed in the space 34 of the housing main body 3, and caulking the rising portion 31 to fix them. doing. Pressure is supplied from the through-hole 33 provided in the lower part of the pressure sensor main body obtained in this way, and the electric output obtained from the pin 23 is used to trim the resistance 22 constituting the electric circuit by laser light, thereby setting the resistance value. The adjustment is performed to adjust the electric circuit.

[0008] The flexible printed circuit board 25 is soldered to the pins 23 of the pressure sensor main body thus adjusted, and the other end of the flexible circuit board 25 is soldered to the terminal 52 of the connector section. The pressure sensor 150 is mounted on the flange 36 of the housing main body via 61 and caulked with the sleeve 9 to complete the pressure sensor 150.

As described above, in the pressure sensor of the type that maintains the airtightness between the space where the pressure is transmitted by the seal member 6 and the space where the electric circuit is disposed, the airtightness is reduced to the measured pressure in the adjusting step. To withstand, and
An upper space is required for adjusting the resistance value of the electric circuit by laser trimming or the like. Further, it is necessary to connect the terminal and the above part after the adjustment. for that reason,
A flange-shaped receiving shape 36 is provided outside the housing body,
It was necessary to fit the connector there and fix it with the sleeve 9.

The pressure sensor having such a configuration requires the sleeve 9 and the O-ring 61, and the number of parts increases.
In addition, there is a problem that the provision of the flange and the sleeve increases the size of the pressure sensor.

On the other hand, the structure of a pressure sensor 160 using a piezoresistive sensor will be described with reference to FIG. The conventional piezoresistive pressure sensor 160 includes a piezoresistive pressure sensor module 10 having a piezoresistor on its surface, an electric circuit board 2 having an electric circuit for converting a change in resistance of the piezoresistor into an electric output, A piezoresistive pressure sensor module and a shield plate for protecting an electric circuit from EMC;
The housing body 3 has a space for accommodating the electric circuit board 2 and the shield plate 8 and having a space connected to the pressure measurement space, and a connector 5 for taking out the electric circuit output to the outside.

Piezoresistive pressure sensor module 10
Is anodically bonded on a rectangular cylindrical glass base 15, and the lower part of the glass base 15 is an inner space 3 of the housing body 3.
4 is fixed to the periphery of the through hole 33 formed in the bottom portion by anodic bonding.

The electric circuit board 2 has an opening in the center of which the piezoresistive pressure sensor module 10 is disposed, and has a circuit element such as a resistor or an arithmetic element constituting a resistance-electric signal conversion circuit on its surface. 22 are provided, and the pins 2 soldered to the electrode pads provided on the substrate 21 are provided.
3, an electric signal is taken out. The electric circuit board 2 is fixed by an adhesive or the like to a step portion facing the internal space 34 of the housing body 3. The electrode pads of the piezoresistive pressure sensor module 10 arranged in the opening of the electric circuit board 2 and the electrode pads provided on the surface of the electric circuit board 2 are connected by gold wires 16 or the like.

A conductive shield plate 8 is mounted on the electric circuit board 2. An opening is provided in the shield plate, and a pin 23 soldered to an electrode pad of the electric circuit board 2 penetrates through a sleeve-shaped dielectric to take out an electric signal to the outside. Electrodes are provided on the inner and outer surfaces of the sleeve by metallizing or the like to form a feedthrough capacitor.

The housing main body 3 is composed of a body portion 35, an internal space 34 provided inside the body portion 35, and a rising portion 31 rising above the space, and the internal space 34 is formed into a pressure measurement space by a through hole 33. Communicating.

After fixing the pressure sensor module 10 and the electric circuit board 2 in the internal space 34 of the housing body 3, pressure is supplied from a through hole 33 provided in a lower part of the pressure sensor body, and the electric power obtained from the pin 23 is supplied. Based on the output, the resistance of the electric circuit is adjusted by trimming the resistance of the electric circuit using laser light to adjust the electric circuit.
In this case, since the piezoresistive pressure sensor module 10 to which pressure is applied is firmly fixed to the housing main body via the glass base 15, the electric circuit can be adjusted by applying pressure from the through hole 33. .

The pin 23 of the pressure sensor body adjusted as described above is passed through the sleeve 9 of the shield plate 8, and is inserted into the opening 522 provided at the tip of the pin lower part 521 of the terminal block 523 provided with the terminal 52. Pin 2
3 and then soldered to the terminal 52.
Is penetrated through an opening provided in the connector portion 5, and the periphery of the connection portion is caulked with the rising portion 31 of the housing body 3 to be integrated to complete the pressure sensor 160.

In the pressure sensor 160 using the piezoresistive pressure sensor having such a configuration, it is not necessary to maintain a particularly airtight condition for adjustment or the like, but a shield plate for ECM countermeasures is provided. It is necessary to attach a feedthrough capacitor for passing through and taking out. For this purpose, a method is employed in which the rising portion 84 of the shield plate 8 is pressed into the inner wall of the internal space 34 of the housing body 3 and fixed. However, in this case, forming the feed-through capacitor by press-fitting the pin 23 into the sleeve having a diameter of, for example, about 0.7 to 1.0 mm of the shield plate 8 to which the feed-through capacitor 81 is attached is high in the arrangement of the pins. In addition to the need for accuracy, it is necessary to consider the effect of the stress at the time of press-fitting the shield plate on the feedthrough capacitor.

On the other hand, as shown in FIG. 9, a pressure sensor 170 having a shield plate 8 formed in a planar shape and a peripheral end thereof sandwiched and fixed between a lower end of the connector 5 and a step provided in the housing 3 is employed. is there. In FIG. 9, each component having the same reference numeral as the component shown in FIG. 8 has substantially the same function.

In the case of the pressure sensor 170 having such a configuration, since the pin 23 is penetrated through the sleeve and soldered to connect a penetrating capacitor, the pin 23 is pressed and caulked from above, so that stress is generated at the pin connection portion. Therefore, there is a concern that the feedthrough capacitor may be destroyed. Further, since the housing 3 and the shield plate 8 are merely pressed against each other, the impedance at high frequencies may be increased due to the contraction of the connector, the oxidation of the housing and the shield plate, and the noise resistance may be degraded. .

[0021]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art. In a pressure sensor using a variable capacitance type pressure sensor or a variable resistance type pressure sensor, an electric sensor is manufactured during the manufacturing process. It is an object of the present invention to provide a pressure sensor capable of adjusting the output and reducing the size of the entire sensor without increasing the number of parts.

Further, according to the present invention, in a pressure sensor using a piezoresistive pressure sensor, the precision of the sleeve provided on the shield plate is not so much a problem, and the pressure is not applied to the shield plate, so that the feedthrough capacitor is adversely affected. It is an object of the present invention to provide a pressure sensor that does not provide the pressure.

[0023]

In order to solve the above-mentioned problems, the present invention provides an electric circuit board, a pressure sensor module, a case, a housing for accommodating the electric circuit board, the pressure sensor module, and the case. In a pressure sensor having a main body and a connector, the housing main body has an inner space that houses the electric circuit board and the pressure sensor module and the case and a rising part that rises around an upper part, and a plurality of slits are formed in the rising part. Was provided.

Further, according to the present invention, in the above-mentioned pressure sensor, notches are provided at the upper part of the periphery of the case and at the lower part of the periphery of the connector. And the connector is swaged.
The pressure sensor module was a variable capacitance type pressure sensor or a variable resistance type pressure sensor.

Further, the present invention relates to a pressure sensor having an electric circuit board, a pressure sensor module, a shield plate, a housing body for accommodating the electric circuit board, the pressure sensor module and the shield plate, and a connector. The housing body has an inner space for accommodating the electric circuit board, the pressure sensor module, and the shield plate, and a rising portion rising up around the upper portion. The plurality of slits are provided in the rising portion, and the pressure sensor module is piezo A part of the periphery of the shield plate is caulked and fixed by the rising portion, and another part of the periphery of the shield plate is sandwiched between a step provided in the internal space of the housing body and the lower end of the connector. It was composed by incorporating.

[0026]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 to 4 are views for explaining a first embodiment of a pressure sensor according to the present invention.
FIG. 2 is a longitudinal sectional view of the pressure sensor, and FIG. 2 is a longitudinal sectional view of a plane rotated by 90 degrees from the section shown in FIG. ing. FIG. 3 is a perspective view of the housing body of the pressure sensor shown in FIGS. 1 and 2, and FIG. 4 is a perspective view of the case and the connector section shown in FIGS.

The pressure sensor 10 according to the first embodiment
Numeral 0 denotes an electric circuit equipped with a pressure sensor module 1 such as a variable capacitance type pressure sensor or a variable resistance type pressure sensor and an electric circuit for converting a change in capacitance or a change in resistance into a current or voltage electric output. A circuit board 2, a case 4 on which the electric circuit board is mounted, a housing body 3 having a space for accommodating the pressure sensor module 1, the electric circuit board 2, and the case 4 and connected to a pressure measurement space; And a connector section 5 for taking out an electric circuit output to the outside.

As in the prior art, the pressure sensor module 1 includes a substrate 11 made of an insulating material such as ceramic,
A pressure response plate 12 made of ceramic or the like held at a predetermined interval by an interval holding member 13 made of a glass adhesive or the like. When the pressure sensor module 1 is composed of a variable capacitance type pressure sensor element, electrostatic electrodes are respectively provided on opposing surfaces of the substrate 11 and the pressure response plate 12, and an electric signal is externally transmitted by the pins 14. It is configured to take out. When the pressure sensor module 1 is constituted by a variable resistance type pressure sensor element, a bridge circuit made of a resistor is provided on the surface of the pressure response
Is configured to extract an electric signal to the outside.

The electric circuit board 2 is provided with circuit elements 22 such as resistors and arithmetic elements constituting a capacitance-electric signal conversion circuit or a resistance value-electric signal conversion circuit on the upper and lower surfaces of a substrate 21. An electric signal is extracted to the outside by a pin 23 soldered to an electrode pad provided on the upper surface of the substrate 21.

The case 4 is made of an insulating material, has a cylindrical shape, and has the electric circuit board 2 mounted and fixed on a step provided therein. Further, the case 4 is provided with a cutout portion 42 and a rising portion 41 on an upper surface thereof. This notch 4
2 and the rising portion 41 are formed by a hanging portion 53 of the connector portion 5 described later.
And the notch 54 are fitted.

The housing body 3 is composed of a body portion 35, an internal space 34 provided inside the body portion 35, and a rising portion 31 rising above the space, and the internal space 34 is connected to a pressure measurement space by a through hole 33. Communicating. further,
The rising portion 31 is provided with a plurality of slits 32, and the rising portion 31 is divided into a caulking portion 314 for fixing the case and a caulking portion 315 for fixing the connector.

The seal member 6, the pressure sensor module 1, and the electric circuit board 2 are provided in the internal space 34 of the housing body 3.
Are fixed to each other, and a case fixing caulking portion 314 of the rising portion 31 is crimped to fix the rising portion 41 of the case 4 to form a pressure sensor main body. The pressure is supplied from the through-hole 33 provided in the lower part of the pressure sensor main body obtained in this way, and the resistance 22 constituting the electric circuit is trimmed with laser light based on the electric output obtained from the pin 23, whereby the resistance is increased. By adjusting the value, the electric circuit is adjusted.

In the pressure sensor body thus adjusted, the hanging part 53 of the connector part 5 has the notch part 42 of the case 4.
The case 4 and the connector portion 5 are arranged so as to fit into the connector portion 5. The pins 23 penetrate through an opening provided on the upper surface of the connector portion 5 and are inserted through an opening 522 provided on a lower end portion 521 of the terminal 52. Caulking part 31 for fixing
The connector portion 5 is integrated by caulking 5. Next, after the pins 23 are soldered to the lower ends 521 of the terminals 52, the connection portions are covered with the resin 7 and protected. Thus, the pressure sensor 100 is completed.

The pressure sensor of the type configured to maintain the airtightness between the space where the pressure is transmitted and the space where the electric circuit is disposed by the sealing material 6 in the adjusting process is a case fixing caulking in the adjusting step. The pressure sensor main body is integrated by the unit 314 so that the airtightness withstands the measurement pressure, and an upper space for adjusting the resistance value of the electric circuit by laser trimming or the like is secured. Further, the pressure sensor body and the connector can be easily connected after the adjustment.

The pressure sensor according to the present invention having the above-described structure is provided with a sleeve 9 and an O-ring 61 as in the prior art.
Becomes unnecessary, and the number of parts can be reduced. Further, in the pressure sensor according to the present invention, the pressure sensor main body and the connector portion can be easily integrated in a small number of steps, and the size of the pressure sensor is not increased.

Next, a second embodiment of the present invention will be described.
The configuration of the pressure sensor 110 using the piezoresistive pressure sensor will be described with reference to FIGS. FIG. 5 is a vertical sectional view of the pressure sensor 110, and FIG.
FIG. 3 is a vertical cross-sectional view of a plane rotated 90 degrees from the cross-section shown in FIG. 1, and shows a position where connection between a terminal and a pin is clearly shown. The piezoresistive pressure sensor 110 according to this embodiment is an electric circuit including a piezoresistive pressure sensor module 10 having a piezoresistor provided on the surface and an electric circuit for converting a change in resistance of the piezoresistor into an electric output. Substrate 2 and piezoresistive pressure sensor module 1
A housing body 3 having an internal space 34 for accommodating the pressure sensor module 10 and the electric circuit board 2 and the shield plate 8 and connected to a pressure measuring space; And a connector section 5 for taking out the output of the electric circuit to the outside.

Piezoresistive pressure sensor module 10
Is anodically bonded onto a rectangular cylindrical glass base 15, and the lower end of the glass base 15 is
4 is fixed to the periphery of the through hole 33 formed in the bottom portion by anodic bonding.

The electric circuit board 2 has an opening in the center of which the piezoresistive pressure sensor module 10 is disposed, and has a circuit element such as a resistor and an arithmetic element constituting a resistance-electric signal conversion circuit on its surface. Is provided, and the substrate 2
Pin 2 soldered to an electrode pad provided on the upper surface of 1
3, an electric signal is taken out. The electric circuit board 2 is fixed by an adhesive or the like to a step portion facing the internal space 34 of the housing body 3. The electrode pads of the piezoresistive pressure sensor module 10 arranged in the opening of the electric circuit board 2 and the electrode pads provided on the surface of the electric circuit board 2 are connected by gold wires 16 or the like.

A conductive shield plate 8 is mounted on the upper part of the electric circuit board 2. An opening is provided in the shield plate 8, and a pin 23 soldered to an electrode pad of the electric circuit board 2 penetrates through a sleeve-like dielectric to take out an electric signal to the outside. Electrodes are provided on the inner surface and the outer surface of the sleeve by metallizing or the like to form a feedthrough capacitor 81.

The housing main body 3 is composed of a body portion 35, an internal space 34 provided inside the body portion 35, and a rising portion 31 rising above the space, and the internal space 34 is formed into a pressure measurement space by a through hole 33. Communicating. Further, a plurality of slits substantially similar to FIG. 3 are provided in the rising portion 31 of the housing main body, and are divided into a caulking portion for fixing the shield plate and a caulking portion for fixing the connector.

In the internal space 34 of the housing body 3, the piezoresistive pressure sensor module 10, the electric circuit board 2
After fixing, the through hole 3 provided in the lower part of the pressure sensor body
Pressure is supplied from 3 and the resistance of the electric circuit is adjusted by trimming the resistance of the electric circuit by using a laser beam based on the electric output obtained from the pin 23, thereby adjusting the electric circuit. In this case, since the piezoresistive pressure sensor module 10 to which pressure is applied is firmly fixed to the housing main body via the glass base 15, it is possible to adjust the electric circuit by applying pressure from the through hole 33. .

The pin 23 of the pressure sensor main body thus adjusted is passed through the sleeve 81 of the shield plate 8, and the pin 23 is inserted into the opening provided at the tip of the pin lower portion 521 of the terminal block 523 provided with the terminal 52. After that, the shield plate 8 is fixed by caulking the shield plate fixing caulking portion of the rising portion 31 of the housing body 3, and then the pin 23 is soldered to the lower end portion 521 of the terminal 52 of the connector portion 5 to be integrated. Become Thereafter, the connector fixing portion of the rising portion 31 of the housing body 3 is swaged to fix the connector portion 5 to the pressure sensor body, thereby completing the pressure sensor 110.

With such a configuration, the pressure sensor 110 according to the present embodiment, when placing the shield plate 8 above the piezoresistive pressure sensor module 10, uses the sleeve of the feedthrough capacitor 81. If the interval is adjusted to be equal to the interval between the pins 23, the position of the through-hole may be the accuracy set to be located on the step portion of the internal space 34 of the housing body 3, and the fixing of the shield plate may be performed by the housing body 3. Can be fixed by the caulking portion for fixing the shield plate in the rising portion 31 of the upper portion 31, and the subsequent steps are simplified. Furthermore, since the end of the shield plate is fixed on the step provided in the internal space of the housing main body and the hanging portion of the connector, no stress is transmitted to the feedthrough capacitor.

[0044]

As described above, according to the present invention, in the pressure sensor, the slit is provided in the upright portion provided in the upper portion of the housing body for housing the pressure sensor module, and the caulking is performed twice. The caulking of the pressure sensor main body and the caulking for integrating the connector portion with the pressure sensor main body can be performed by the caulking portion provided on the housing main body without using another fixing member, which reduces the number of parts and the sensor itself. The size can be reduced.

Further, according to the present invention, in a pressure sensor using a piezoresistive pressure sensor module, a slit is provided in a rising portion provided in an upper portion of a housing body for housing the pressure sensor module, and caulking is divided into two times. The caulking that forms the pressure sensor body by fixing the shield plate and the caulking that fixes the pressure sensor body and the connector part are provided on the housing body without using other fixing members. Since the number of parts can be reduced and the size of the sensor itself can be reduced, when fixing the housing body to the connector, the swaging pressure is not transmitted to the shield plate without transmitting to the shield plate. This will not cause damage.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing the structure of a pressure sensor according to the present invention.

FIG. 2 is a longitudinal sectional view at a section rotated by 90 degrees from the longitudinal sectional view shown in FIG. 1;

FIG. 3 is a perspective view showing a shape of a housing main body used for the pressure sensor according to the present invention.

FIG. 4 is a perspective view showing the shape of a case and a connector used for the pressure sensor according to the present invention.

FIG. 5 is a longitudinal sectional view showing the structure of a pressure sensor according to a second embodiment of the present invention.

FIG. 6 is a longitudinal sectional view at a section rotated by 90 degrees from the longitudinal sectional view shown in FIG. 1;

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

FIG. 8 is a longitudinal sectional view showing the structure of another conventional pressure sensor.

FIG. 9 is a longitudinal sectional view showing the structure of still another conventional pressure sensor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pressure sensor module 2 Circuit board 3 Housing main body 4 Case 5 Connector part 6 Seal member 7 Adhesive 8 Shield plate 9 Sleeve 10 Pressure sensor module (piezoresistive type) 11 Substrate 12 Pressure response plate 13 Glass adhesive 14 Pin 15 Glass base Table 16 Gold wire 21 Electric circuit board 22 Circuit element 23 Pin 25 Flexible board 31 Rise 32 Slit 33 Through hole 34 Internal space 35 Body part 41 Rise 42 Cutout 51 Connector 52 Terminal 53 Hanging lower part 54 Cutout 61 O-ring 81 Feed-through capacitor (sleeve) 82 Flange

Claims (7)

[Claims] 1. A pressure sensor comprising: an electric circuit board, a pressure sensor module, a case, a housing body that houses the electric circuit board, the pressure sensor module, the case, and a connector. A pressure sensor having an internal space for housing an electric circuit board, a pressure sensor module, and a case and a rising portion rising around the upper portion, wherein a plurality of slits are provided in the rising portion. 2. The pressure sensor according to claim 1, wherein notches are provided at an upper portion of the periphery of the case and at a lower portion of the periphery of the connector so as to fit each other. 3. The upright portion provided on the case body is divided into a portion for caulking the case portion and a portion for caulking the connector portion by slits. Pressure sensor. 4. The pressure sensor according to claim 1, wherein the pressure sensor module is a variable capacitance type pressure sensor or a variable resistance type pressure sensor. 5. A pressure sensor having an electric circuit board, a pressure sensor module, a shield plate, a housing body that houses the electric circuit board, the pressure sensor module, and the shield plate, and a connector, wherein the housing body is A pressure sensor having an internal space for accommodating the electric circuit board, the pressure sensor module, and the shield plate, and a rising portion rising around the upper portion, and a plurality of slits provided in the rising portion. 6. The pressure sensor according to claim 5, wherein the pressure sensor module is a piezoresistive pressure sensor. 7. A portion of the shield plate is fixed by caulking at the periphery thereof, and another portion of the periphery is sandwiched between a step provided in an internal space of the housing and a lower end of the connector. The pressure sensor according to claim 6, wherein