JPH10300616A - 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 and high efficiency. SOLUTION: There is formed an insertion hole 41 having such a size that a pressure introducing pipe 17 can be inserted with a margin into the leading end faces of a plurality of piping terminals 4 branched from pressure piping, and the inside of the piping terminal 4, a ring-like member 5 having a substantially same outer peripheral shape as the inner peripheral shape of the piping terminal 4 and forming a contact part 51 with the lading end part of the pressure introducing pipe 17 in an inner peripheral part is provided movably to a longitudinal direction along the inner peripheral face of the piping terminal 4, and the pressure introducing pipe 17 is inserted into the insertion hole 41, and the leading end part of the pressure introducing pipe 17 is brought into contact with the contact part 51 of the ring-like member 5, and pressure is introduced into a sensor main body via the piping terminal 4 and pressure introducing pipe 17, and an electric signal caused corresponding to bending of a diaphram 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 measuring device for measuring pressure characteristics by applying a pressure through a pressure applying jig, the device having a plurality of pipe terminals branched from a pressure pipe, and the pressure end is provided on a tip end surface of the pipe terminal. An insertion hole large enough to allow the introduction pipe to be inserted with a margin is formed. Inside the piping terminal, the outer peripheral shape is substantially the same as the inner peripheral shape of the piping terminal. A pressure applying jig is formed by providing a ring-shaped member having a contact portion with the tip of the pipe so as to be movable in the length direction along the inner peripheral surface of the piping end, and thereby forming the pressure introducing jig. Insert the pipe into the insertion hole of the pipe end Into the pressure sensor body through the pressure end of the pressure introducing pipe through the piping end and the pressure introducing pipe from the pressure pipe, and caused by the introduced pressure. An electric signal generated according to the deflection of the diaphragm 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 ring-shaped air passage hole is provided on the inner peripheral surface of the pipe terminal at a position deeper than the installation position of the ring-shaped member. It is characterized in that a projection is formed.

According to a third aspect of the present invention, in the first or second aspect of the invention, grease is interposed between the ring-shaped member and an inner peripheral surface of the pipe terminal. It is.

[0014]

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 according to a pressure sensor characteristic measuring device showing an example of an embodiment of the present invention. The actual shape of the pipe terminal 4 is a cylindrical shape rotated about the XY axis in the figure, but is not limited to the cylindrical shape. The pressure sensor characteristic measuring device according to the present embodiment includes a plurality of pipe terminals 4.
And a ring-shaped member 5 installed in the piping terminal 4, and a wiring board 3 on which an IC socket 31 is mounted.

The pipe terminal 4 is formed to branch off from the pressure pipe 24, and an insertion hole 41 is formed at the tip end of the pipe so that the pressure introducing pipe 18 can be inserted with a margin. Therefore, there is a gap between the outer peripheral surface of the pressure introducing pipe 18 and the insertion hole 41 with the pressure introducing pipe 18 inserted. Piping terminal 4
Inside, the outer peripheral shape is substantially the same as the inner peripheral shape of the pipe end 4, and the inner peripheral portion has a contact portion 5 with the distal end of the pressure introducing pipe 17.
A ring-shaped member 5 such as a rubber O-ring formed with 1 is slidably provided in the longitudinal direction along the inner peripheral surface of the pipe terminal 4. The contact portion 51 can be configured by, for example, forming a taper as shown in FIG. 1, but is not limited to this shape. Further, a slight gap between the ring-shaped member 5 and the inner peripheral surface of the pipe terminal 4 is filled with grease 52, and the grease 52 maintains airtightness and the inner periphery of the pipe terminal 4 of the ring-shaped member 5. Movement along the surface is performed smoothly.
Reference numeral 42 denotes a ring-shaped projection formed by forming a node on the inner peripheral surface of the pipe terminal 4 and then penetrating the center portion in a circular shape to form an air passage hole 43. It is provided at a position on the far side. When the ring-shaped member 5 is out of the installed state on the inner peripheral surface of the pipe terminal 4, the ring-shaped protrusion 42 is inserted into the other pipe terminal 4 through the inside of the pipe terminal 4. , To prevent the measurement of the characteristics of other pressure sensors from being hindered.

When the characteristic is measured by the pressure sensor characteristic measuring device of the present embodiment, first, as shown in FIG. 2A, the ring-shaped member 5 is mounted near the tip end surface of the pipe terminal 4. In advance, as shown in FIG. 2B, the piping terminal 4 is connected to 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. By pushing the pressure introduction pipe 17 of the pressure sensor into the insertion hole 41 so as to be inserted, the pipe terminal 4 is attached to the pressure introduction pipe 17. Here, when the pressure introducing pipe 17 is pushed in so as to be inserted into the insertion hole 41, the distal end of the pressure introducing pipe 17 comes into contact with the contact portion 51 of the ring-shaped member 5, and pushes up the ring-shaped member 5. At this time, the ring-shaped member 5 can move smoothly along the inner peripheral surface of the pipe terminal 4 by the action of the grease 52.

In this state, when pressure is introduced from the pressure pipe 24 through the pipe terminal 4 of the pressure applying jig 6 and pressurized, the pressure is applied to the inside of the pressure sensor body 1 through the pressure introduction pipe 17 of the pressure sensor. Applied to the diaphragm 16. 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 ring-shaped member 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 tip of the pressure introducing pipe 17 of the pressure sensor and the contact portion 51 of the ring-shaped member 5 in the pipe terminal 4 come into contact with each other. Since the piping terminal 4 and the pressure introducing pipe 17 are connected to each other, even if the wiring board 3 and the piping terminal 4 are misaligned, the pressure introducing pipe 17 is not affected by the lateral displacement.
Is absorbed by the gap between the outer peripheral surface of the pipe and the insertion hole 41 of the pipe terminal 4, and the ring-shaped member 5
Is absorbed by the movement in the length direction along the inner peripheral surface of the piping terminal 4, so that 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 4 and the wiring board 3, etc., 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.

[0019]

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 measuring a pressure characteristic by applying a pressure via a pressure applying jig. It has a plurality of piping ends, an insertion hole large enough to allow the pressure introduction pipe to be inserted with a margin in the tip end surface of the piping terminal, inside the piping terminal, the outer peripheral shape is the The inner peripheral shape of the pipe end is substantially the same, and a ring-shaped member having an inner peripheral portion formed with a contact portion with the distal end of the pressure introducing pipe is formed in the longitudinal direction along the inner peripheral surface of the pipe end. Pressure is provided by providing it to be movable A jig is formed, the pressure introducing pipe is inserted into an insertion hole of the piping end, and a tip end of the pressure introducing pipe is brought into contact with a contact part of the ring-shaped member. Pressure is introduced into the pressure sensor body via a 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, the mechanical stress is caused by the gap between the outer peripheral surface of the pressure introducing pipe and the insertion hole of the piping terminal and the lengthwise movement of the ring-shaped member along the inner peripheral surface of the piping terminal. ,
It absorbs and suppresses the generation of mechanical stress, and furthermore, the pressure sensor body is directly exposed to the atmosphere in the thermostatic chamber, and a pressure sensor characteristic measuring device that can measure characteristics with high accuracy and high efficiency Could be provided.

According to a second aspect of the present invention, in the first aspect of the present invention, an air passage hole is provided on the inner peripheral surface of the pipe terminal at a position deeper than the installation position of the ring-shaped member. If the ring-shaped projection is formed, even if the ring-shaped member is displaced from the installation state on the inner peripheral surface of the pipe terminal, the ring-shaped member does not enter another pipe terminal through the inside of the pipe terminal, and This can prevent the characteristic measurement of the pressure sensor from being hindered.

According to the third aspect of the invention, in the first or second aspect of the invention, if grease is interposed between the ring-shaped member and the inner peripheral surface of the pipe end, The airtightness is maintained, and the ring-shaped member is smoothly moved along the inner peripheral surface of the pipe end.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a cross-sectional state of a pipe terminal 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 Ring member 6 Pressure application jig 16 Diaphragm 17 Pressure introduction pipe 18 External terminal 24 Pressure piping 31 Socket 41 Insertion hole 42 Ring-shaped projection 51 Contact part 52 Grease

Claims (3)

[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 measuring device for measuring pressure characteristics by applying a pressure to a pressure sensor through a pressure applying jig, the device having a plurality of pipe terminals branched from a pressure pipe, and a tip of the pipe terminal On the surface, an insertion hole large enough to allow the pressure introduction pipe to be inserted with a margin is formed, and inside the piping terminal, the outer peripheral shape is substantially the same as the inner peripheral shape of the piping terminal, and in the inner peripheral portion. Constitutes a pressure applying jig by providing a ring-shaped member having a contact portion with the distal end portion of the pressure introduction pipe so as to be movable in the length direction along the inner peripheral surface of the piping end. And the pressure introduction pipe is connected to the pipe end. Insert the end of the pressure introduction tube into the contact portion of the ring-shaped member, and introduce pressure from the pressure piping to the pressure sensor main body through the piping terminal and the pressure introduction tube, An electric signal generated according to the deflection of the diaphragm caused by the introduced pressure is taken out from the external terminal. 2. A ring-shaped projection having an air passage hole is formed at a position on the inner peripheral surface of the pipe end farther from a position where the ring-shaped member is installed. Pressure sensor characteristic measuring device. 3. The pressure sensor characteristic measuring device according to claim 1, wherein grease is interposed between the ring-shaped member and an inner peripheral surface of the pipe end.