JPH10300618A - Characteristic measuring device of pressure sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the characteristic measuring device of a pressure sensor capable of suppressing generation of mechanical stress and measuring characteristics with high precision. SOLUTION: In the characteristic measuring device of a pressure sensor which measures pressure characteristics by applying pressure via a pressure applying jig, the pressure applying jig is constituted by a plurality of piping terminals 4 which are branched from pressure piping, and in which a through hole is formed on a leading end face; and a cylindrical body 5 in which an introducing hole 52 having a contact part 51 with the leading end part of a pressure introducing pipe 17 in an inner peripheral part is formed at the one end and the other end is released, and which has the substantially same outer peripheral configuration as that of the through hole and is movable in a longitudinal direction of a piping terminal 4. The leading end part of the pressure introducing pipe 17 is brought into contact with the contact part 51 formed in a marginal part of the introducing hole 52 of the cylindrical body 5, and pressure is introduced from a pressure pipe into a pressure sensor main body 1 via the piping terminal 4, cylindrical body 5 and pressure introducing pipe 17, and an electric signal caused corresponding to bending of a diaphram caused by the introduced pressure is fetched out from an external terminal 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a characteristic measuring device for measuring a pressure characteristic of a pressure sensor.

[0002]

2. Description of the Related Art A pressure sensor chip having a diaphragm structure utilizes a piezo effect. As shown in FIG. 3, a piezo resistor 12, a field oxide film 13, An electrode wiring 15 for extracting an electrode from the silicon nitride film 14 and the piezoresistor 12 is formed, and the semiconductor substrate 11 is anisotropically etched on the back side by an anisotropic etching technique.
A diaphragm 16 is formed. Then, these are covered with a cover to form a pressure sensor main body. A pressure sensor is composed of the pressure sensor main body and an external terminal connected to a pressure introducing pipe and electrode wiring 15 described later. Reference numeral 19 denotes an electrode pad that is in ohmic connection with the electrode wiring 15. The principle of operation of this pressure sensor is that when the diaphragm 16 bends under pressure, a stress corresponding to the amount of deflection is generated in the piezoresistor 12. The resistance value of the piezoresistor 12 changes according to this stress, and this is detected as a change in an electric signal.

[0003] The characteristics of this pressure sensor are that it uses silicon, so that it is smaller and more sensitive than the conventional Bourdon tube type, and it has good reproducibility and high reliability. can give.

[0004] Measuring equipment for measuring the pressure characteristics of such a pressure sensor generally includes a pressure generator, a constant voltage power supply or a constant current power supply, a voltmeter or an ammeter, a thermostat, and automatic control of these. And the like. Then, the pressure sensor to be measured is incorporated in a pressure applying jig for applying pressure, and is put in a constant temperature layer together with an output extracting section for outputting a signal indicating a pressure characteristic from the pressure sensor to the outside. Various characteristics are measured in the temperature state.

Here, as shown in FIG. 4, the pressure applying jig 2 is made of metal such as aluminum and has a hollow portion 21 therein.
It has a plurality of pressure introduction holes 22 connected to the hollow portion 21 and corresponding to the pressure introduction pipe 17 for introducing pressure to the diaphragm 16 in the pressure sensor main body 1. To extract the output,
This is performed by using a circuit board on which a plurality of IC sockets 31 are mounted.

[0006] An external terminal 18 for taking out an electric signal of the pressure sensor to be measured to the outside is inserted into the IC socket 31 of the wiring board 3 so that the pressure introducing pipe 17 faces in the opposite direction to the wiring board 3 side. Next, the pressure applying jig 2 is mounted so that the pressure introducing pipe 17 fits into the pressure introducing hole 22. At this time, a stopper 32 as a spacer between the wiring board 3 and the pressure applying jig 2 is interposed therebetween. The stopper 32 is fixed to the wiring board 3 in advance, and the pressure applying jig 2 and the stopper 32 are fixed with the screw 23. The pressure applying jig 2 is provided with a pressure pipe 24, pressure is introduced from the pressure pipe 24 into the pressure introducing hole 22 through the hollow portion 21, and furthermore, the pressure sensor main body through the pressure introducing pipe 17. 1 to be introduced into the diaphragm 16.

[0007]

However, in the above-described method of measuring the pressure characteristics of the pressure sensor, the method for measuring the pressure characteristics of the pressure sensor is described as follows. When the positional displacement occurs in the direction, a stress mainly in the horizontal direction is applied to the pressure introducing pipe 17 by the pressure applying jig 2. This stress is applied to the diaphragm 16 in the pressure sensor main body 1, and the pressure characteristic changes. Further, since the pressure applying jig 2 is formed integrally so as to measure the characteristics of a plurality of pressure sensors with one pressure applying jig 2, the displacement of one pressure sensor becomes the whole displacement, Stress will also be applied to other pressure sensors.

Further, when the pressure applying jig 2 is fixed by a plurality of screws 23 and the tightening torque of the screws 23 varies, the pressure applying jig 2 slightly tilts and warps, There is a problem that the same stress as described above is applied to the pressure introducing pipe 17 of the sensor, and the pressure characteristics fluctuate.

Another problem is that the temperature characteristic such as temperature characteristic measurement is one of the important items among the characteristic items of the pressure sensor, but the efficiency of the temperature characteristic measurement is low. . In other words, in order to simultaneously measure a large number of pressure sensors with the integrated pressure applying jig 2, the volume of the pressure applying jig 2 increases, and the heat capacity thereof increases. In addition, since the pressure sensor to be measured is sealed by the wiring board 3, the pressure applying jig 2, and the stopper 32, even if the pressure characteristic is measured by changing the ambient temperature, It takes time for the temperature to change, and the efficiency of the measurement becomes poor.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to suppress the generation of mechanical stress and to measure the characteristics of a pressure sensor with high accuracy and high efficiency. Is to provide.

[0011]

According to the first aspect of the present invention,
For a pressure sensor having a pressure sensor main body, a pressure introducing pipe for introducing pressure to a diaphragm in the pressure sensor main body, and an external terminal for taking out an electric signal output according to the deflection of the diaphragm to the outside. A pressure sensor characteristic measuring device that measures pressure characteristics by applying pressure via a pressure applying jig, the plurality of pipe terminals branched from a pressure pipe and having a through hole formed in a tip surface, An introduction hole having an abutting portion with the tip of the pressure introduction tube is formed at one end on the inner periphery, the other end is opened, the outer periphery is substantially the same as the shape of the through hole, and the length of the pipe end is A pressure applying jig is configured with the cylindrical body that is movable in the direction, and the leading end of the pressure introducing tube is brought into contact with a contact portion formed at a peripheral portion of an introduction hole of the cylindrical body, From the pressure pipe through a pipe terminal, a tubular body and a pressure introduction pipe Introducing a pressure into the pressure sensor body Te,
An electric signal generated according to the deflection of the diaphragm caused by the introduced pressure is taken out from the external terminal.

According to a second aspect of the present invention, in the first aspect of the present invention, a stopper is provided at an open end of the tubular body.

According to a third aspect of the present invention, in the first or second aspect of the present invention, a tapered portion is provided at an open end of the cylindrical body for facilitating introduction of an introduction pressure into the cylindrical body. It is characterized by the following.

According to a fourth aspect of the present invention, in the first to third aspects of the present invention, a ring-shaped projection having an air passage hole is formed on an inner peripheral surface of the pipe end. It is.

According to a fifth aspect of the present invention, in the first to fourth aspects of the present invention, grease is interposed between an outer peripheral portion of the tubular body and a through hole of the pipe end. Is what you do.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram of a cross-sectional state of a pipe terminal 4 and a tubular body 5 according to a pressure sensor characteristic measuring device showing an example of an embodiment of the present invention. Piping terminal 4
Although the actual shapes of and have a cylindrical shape rotated about the X-Y axis in the figure, they are not limited to the cylindrical shape. The characteristic measuring device of the pressure sensor according to the present embodiment includes:
Pressure applying jig 6 composed of a plurality of pipe terminals 4 and cylindrical body 5
And the wiring board 3 on which the IC socket 31 is mounted.

The pipe terminal 4 is formed to branch off from the pressure pipe 24, and a through hole 41 having substantially the same shape as the outer peripheral shape of the tubular body 5 is formed at the tip end surface.

The cylindrical body 5 has a pressure introducing hole 52 having an abutting portion 51 at one end with an end portion of the pressure introducing pipe 17 at an inner peripheral portion.
Is formed, the other end is opened, the outer peripheral shape is substantially the same as the shape of the through hole 41, and the outer peripheral shape is provided movably in the length direction of the pipe terminal 4. As the contact portion 51, for example, FIG.
Although it can be constituted by forming a taper as shown in (1), it is not limited to this shape. At the open end of the tubular body 5, a locking portion 53 as a retaining portion is formed, and the locking portion 53 is hooked on the peripheral edge portion 44 on the tip end surface of the pipe terminal 4, so that the tubular body 5 is connected to the pipe terminal 4. From falling off. In addition, a tapered portion 54 is formed at the open end of the tubular body 5 so that an introduction pressure is easily introduced into the inside of the tubular body 5.

The outer peripheral portion of the cylindrical body 5 and the through hole 4 of the pipe terminal 4
A small gap between the inner surface of the pipe 1 and the inner surface of the pipe 1 is filled with grease 7 to maintain airtightness by the grease 7 and smoothly move the tubular body 5 along the length direction of the pipe end 4. Is being done. Reference numeral 42 denotes a ring-shaped projection formed by forming a node on the inner peripheral surface, then penetrating the center portion in a circular shape to form an air passage hole 43, and even when the cylindrical body 5 is pushed in. It is provided at a position where the tubular body 5 does not contact. The ring-shaped projections 42 are formed such that when the tubular body 5 has completely entered the inside of the piping terminal 4, the tubular body 5 passes through the inside of the piping terminal 4 and enters another piping terminal 4. This is to prevent the measurement of the characteristics of the pressure sensor from being hindered.

When the characteristic is measured by the pressure sensor characteristic measuring device of the present embodiment, first, as shown in FIG. With the pressure sensor main body 1 fixed to the wiring board 3 by inserting the external terminal 18 into the socket 31 installed on the wiring board 3 from the state where the pressure sensor
The pipe terminal 4 is pushed down toward the pressure sensor while the distal end of the pressure introducing pipe 17 of the pressure sensor is in contact with the contact portion 51 of the tubular body 5. Then, as shown in FIG. 2 (b), the tubular body 5 is pushed into the inside of the pipe terminal 4, and the pressure applying jig 6 composed of the pipe terminal 4 and the tubular body 5 is attached to the pressure introducing pipe 17. You. At this time, the cylindrical body 5 can smoothly move in the length direction of the pipe terminal 4 by the action of the grease 7.

In this state, when pressure is introduced from the pressure pipe 24 through the pipe end 4 of the pressure applying jig 6 and the cylindrical body 5 and pressurized, the pressure is increased through the pressure introducing pipe 17 of the pressure sensor. The voltage is applied to the diaphragm 16 in the sensor body 1. By extracting an electric signal output from the external terminal 18 through the external terminal 18 in accordance with the pressure applied to the diaphragm 16, the pressure characteristic can be measured. Here, when pressure is applied to the inside of the pipe terminal 4, the cylindrical body 5 is pushed downward in the drawing by this pressure, so that the state of contact with the distal end of the pressure introducing pipe 17 becomes stronger, The airtightness of the contact portion is increased.

According to the present embodiment, when the pressure from the pressure pipe 24 is applied, the end of the pressure introducing pipe 17 of the pressure sensor and the contact portion 51 of the tubular body 5 are brought into contact with each other, so that Since the connection with the introduction pipe 17 is made, even if the wiring board 3 or the piping terminal 4 is misaligned, the displacement in the vertical direction is not affected by the lengthwise direction of the piping terminal 4 of the cylindrical body 5. Since it is absorbed by the movement, the mechanical stress applied to the pressure sensor is reduced. Further, since the pressure sensor main body 1 is not hermetically sealed by the pressure applying jig 6, the wiring board 3, and the like, the pressure sensor main body 1 is directly exposed to the atmosphere in the constant temperature bath. Therefore, when the pressure characteristic is measured by changing the ambient temperature in the constant temperature bath, the temperature of the pressure sensor changes following the change in the ambient temperature, so that the efficiency of the characteristic measurement does not deteriorate.

[0023]

As described above, according to the first aspect of the present invention, the pressure sensor main body, the pressure introducing pipe for introducing pressure to the diaphragm in the pressure sensor main body, and the output according to the deflection of the diaphragm. A pressure sensor having an external terminal for taking out an electrical signal to be applied to the outside, and a pressure sensor for measuring pressure characteristics by applying pressure via a pressure applying jig, Branched from the pipe, a plurality of pipe terminals having a through hole formed on the tip surface, an introduction hole having a contact portion with the tip of the pressure introduction pipe on the inner periphery at one end is formed, and the other end is opened, An outer peripheral shape is substantially the same as the shape of the through-hole, and a pressure applying jig is constituted by a tubular body movable in a longitudinal direction of the piping terminal, and a tip end of the pressure introducing pipe is formed by the cylindrical member. Abuts on the abutment formed on the periphery of the inlet So, the pipe terminal from the pressure line,
Pressure is introduced into the pressure sensor main body through the cylindrical body and the pressure introduction pipe, and an electric signal generated in accordance with the deflection of the diaphragm caused by the introduced pressure is taken out from the external terminal. Even if a displacement or the like occurs between the sensor and the like, the mechanical stress is absorbed by the movement of the tubular body in the longitudinal direction of the pipe end, thereby suppressing the occurrence of the mechanical stress and further reducing the pressure. Since the sensor body was directly exposed to the atmosphere in the thermostat, it was possible to provide a pressure sensor characteristic measuring device capable of measuring characteristics with high accuracy and high efficiency.

According to the second aspect of the present invention, in the first aspect of the present invention, if a stopper is provided at the open end of the tubular body, the tubular body completely enters the inside of the pipe terminal. In this case, it is possible to prevent the tubular body from passing through the inside of the piping terminal and entering another piping terminal, thereby preventing the characteristic measurement of another pressure sensor from being hindered.

According to the third aspect of the present invention, in the first or second aspect of the present invention, a tapered portion for facilitating introduction pressure into the cylindrical body is provided at an open end of the cylindrical body. If provided, the applied pressure can be efficiently introduced.

According to the fourth aspect of the invention, in the first to third aspects of the invention, if a ring-shaped projection having an air passage hole is formed on the inner peripheral surface of the pipe end,
Even when the tubular body has completely entered the inside of the piping terminal, the tubular body passes through the inside of the piping terminal and enters another piping terminal, which hinders the measurement of characteristics of other pressure sensors. Can be prevented.

According to a fifth aspect of the present invention, in the first to fourth aspects of the present invention, grease is interposed between an outer peripheral portion of the cylindrical body and a through hole of the pipe end. For example, airtightness is maintained, and the tubular body is smoothly moved in the length direction of the pipe terminal.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a cross-sectional state of a pipe terminal and a tubular body according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing a cross-sectional state of a schematic configuration of a pressure sensor characteristic measuring device according to an embodiment of the present invention.

FIG. 3 is a schematic diagram showing a cross section of a pressure sensor chip.

FIG. 4 is a schematic diagram showing a schematic configuration of a conventional pressure sensor characteristic measuring device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pressure sensor main body 3 Wiring board 4 Piping terminal 5 Cylindrical body 6 Pressure application jig 7 Grease 16 Diaphragm 17 Pressure introduction pipe 18 External terminal 24 Pressure piping 31 Socket 41 Through hole 42 Ring-shaped projection 43 Passing hole 44 Peripheral edge 51 Contact part 52 Inlet hole 53 Lock part 54 Taper part

Claims (5)

[Claims] 1. A pressure sensor having a pressure sensor main body, a pressure introduction pipe for introducing pressure to a diaphragm in the pressure sensor main body, and an external terminal for taking out an electric signal output in accordance with the deflection of the diaphragm. A pressure sensor characteristic measuring device for measuring pressure characteristics by applying a pressure to a pressure sensor via a pressure applying jig, the pressure sensor being branched from a pressure pipe and having a through-hole formed at a tip end surface. The piping terminal, an introduction hole having an abutting portion with the tip of the pressure introduction tube is formed at one end on the inner periphery and the other end is opened, and the outer periphery shape is substantially the same as the shape of the through hole. A pressure application jig is constituted by a tubular body movable in the length direction of the pipe end, and a tip portion of the pressure introduction pipe is formed at a contact portion formed at a peripheral portion of an introduction hole of the tubular body. From the pressure pipe, the pipe end, the tubular body and the pressure. Pressure measurement is performed by introducing pressure into the pressure sensor main body through a force introduction pipe, and extracting an electric signal generated according to the deflection of the diaphragm caused by the introduced pressure from the external terminal. apparatus. 2. The pressure sensor characteristic measuring device according to claim 1, wherein a retaining portion is provided at an open end of said cylindrical body. 3. The characteristic of the pressure sensor according to claim 1, wherein a tapered portion is provided at an open end of the cylindrical body so as to easily introduce an introduction pressure into the cylindrical body. measuring device. 4. The pressure sensor characteristic measuring device according to claim 1, wherein a ring-shaped projection having an air passage hole is formed on an inner peripheral surface of the pipe end. 5. The pressure sensor characteristic measuring device according to claim 1, wherein grease is interposed between an outer peripheral portion of the cylindrical body and a through hole of the pipe end.