JP2002168717A - Pressure measuring instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low-priced pressure measuring instrument capable of preventing rainwater, corrosive gases, dust, or the like, from invading thereinto by a simple structure and capable of stably measuring pressures. SOLUTION: This pressure measuring instrument is equipped with a body incorporating a measuring diaphragm therein, a reference pressure chamber provided on one side of the diaphragm with the atmospheric pressure applied thereto, and a venthole provided in the body to cause the pressure chamber to communicate with the exterior. This instrument is characterized by having an absorption diaphragm chamber provided in a ring-shape in the body to communicate with the venthole and an absorption diaphragm provided in a ring- shape so as to seal the diaphragm chamber against the exterior and absorbing changes in the volume of air in the venthole owing to changes in the use environment temperature and variations in the atmospheric pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure measuring device capable of preventing rainwater, corrosive gas, dust and the like from entering with a simple structure and capable of performing stable pressure measurement.

[0002]

2. Description of the Related Art FIG. 3 is an explanatory view of the configuration of a conventional example generally used in the prior art.
No. in the official gazette. FIG. 4 is a detailed explanatory view of a main part of FIG. In the figure, 1 is a sensor chip. In this case, silicon is used.

[0005] Reference numeral 2 denotes a concave portion provided on the sensor chip 1 and constituting a measurement diaphragm 3 serving as a strain-flexing portion on the sensor chip 1. Reference numeral 4 denotes a semiconductor pressure detecting element provided on the strain generating portion 3 of the sensor chip 1.

[0004] Reference numeral 5 denotes a glass support substrate made of Pyrex (registered trademark) glass, one surface of which is connected to one surface of the sensor chip and which forms the recess 2 and the reference pressure chamber 6. In this case, it is joined to the sensor chip 1 by anodic bonding or the like.

[0005] Reference numeral 7 denotes a communication hole provided on the glass support substrate 5 and communicating with the pressure introduction chamber 6. 8 is a main body. The other surface of the glass support substrate 5 is joined. Reference numeral 9 denotes a bonding wire for electrically connecting the signal extraction pin 11 provided on the main body 8 to the semiconductor pressure detecting element 4.

The signal extracting pin 11 is connected to the main body 8.
Is filled in the space formed by the main body 8, the sensor chip 1, and the glass support substrate 5.

[0007] In this case, silicone oil defoamed in a vacuum is used as the filling liquid 101. The seal diaphragm seals the sealed liquid 101 with the main body 8.

The ventilation hole 15 is provided in the main body 8.
One end is connected to the communication hole 7 and the other end is open to the outside. The amplifier case 16 is mounted on the main body 8 via an O-ring 17 to ensure airtightness and waterproofness.

In the above configuration, when the measurement pressure P1 is applied to the filling liquid 101 and the atmospheric pressure P0 is applied to the reference pressure chamber 6, the measurement diaphragm 3 is displaced by the pressure P1 minus the pressure P0. When this displacement is electrically detected by the semiconductor pressure detecting element 4, an electric signal output corresponding to the pressure P1 and the pressure P0 is obtained.

[0010]

Generally, an atmospheric pressure reference pressure measuring device used for industrial measurement has an open side to the atmosphere.
Silicon oil or the like is not sealed due to manufacturing costs, and a vent hole 15 is provided on the open side of the pressure sensor 1 to the atmosphere, from which the atmospheric pressure directly contacts the pressure sensor 1.

For this reason, in a pressure measuring device which is often installed outside, rainwater, corrosive gas, dust and the like enter the pressure sensor 1 and cause an error. Amplifier case 15
Even if the vent hole 15 is opened, there is no point because the amplifier case 15 is airtight to ensure waterproofness.

An object of the present invention is to solve the above-mentioned problems, and to provide an inexpensive pressure measuring device which can prevent intrusion of rainwater, corrosive gas, dust and the like with a simple structure, can perform stable pressure measurement, and can provide a low-cost pressure measuring device. Is to do.

[0013]

In order to achieve the above object, according to the present invention, there is provided a pressure measuring apparatus as set forth in claim 1, wherein a main body having a built-in measuring diaphragm, and one surface side of the measuring diaphragm. A pressure measurement device provided with a reference pressure chamber to which atmospheric pressure is applied and a ventilation hole provided in the main body and communicating the reference pressure chamber with the outside. An absorption diaphragm chamber communicating with the ventilation hole, and a volume change due to a change in the temperature of the use environment and a change in the volume of air in the ventilation hole due to a change in atmospheric pressure due to a ring-shaped seal provided between the absorption diaphragm chamber and the outside. And an absorbing diaphragm for absorbing the amount.

According to a second aspect of the present invention, in the pressure measuring device according to the first aspect, the absorption diaphragm is made of stainless steel.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. FIG. 1 is an explanatory diagram of a main part configuration of an embodiment of the present invention,
FIG. 2 is a perspective view of FIG. In the figure, the configuration of the same symbol as FIG. 3 represents the same function. Hereinafter, only differences from FIG. 3 will be described.

In the figure, an absorption diaphragm chamber 21 is
The main body 8 is provided in a ring shape and communicates with the vent hole 15.

The absorption diaphragm 22 is provided in a ring shape by sealing the absorption diaphragm chamber 21 and the outside, and changes in volume due to a change in the ambient temperature and a change in the volume of air in the ventilation hole 15 due to a change in atmospheric pressure. Absorb quantity.

In this case, the absorbing diaphragm 22 is made of a metal material, and is made of a stainless steel material.

In the above configuration, when the measurement pressure P1 is applied to the filling liquid 101 and the atmospheric pressure P0 is applied to the reference pressure chamber 6, the measurement diaphragm 3 is displaced by the pressure P1 minus the pressure P0.

When this displacement is electrically detected by the semiconductor pressure detecting element 4, an electric signal output corresponding to the pressure P1 and the pressure P0 is obtained.

Since the absorption diaphragm 22 is provided in the absorption diaphragm chamber 21, it is possible to prevent rainwater, corrosive gas, dust and the like from entering, and the atmospheric pressure is accurately introduced into the reference pressure chamber 6.

As a result, (1) the absorption diaphragm chamber 21 is provided in a ring shape by sealing the outside from the outside, and a volume change due to a change in the volume of air in the ventilation hole 15 due to a change in the use environment temperature and a change in the atmospheric pressure. Since the absorption diaphragm 22 for absorbing the amount is provided, it is possible to prevent the intrusion of rainwater, corrosive gas, dust and the like with a simple configuration, and to obtain a pressure measurement device capable of performing stable pressure measurement.

(2) The absorption diaphragm chamber 21 is provided in a ring shape by sealing the outside from the outside, and absorbs a volume change due to a change in the volume of air in the ventilation hole 15 due to a change in the use environment temperature and a change in the atmospheric pressure. Absorbing diaphragm 22
Is provided, a simple product design becomes possible with a simple configuration, and an inexpensive pressure measuring device can be obtained.

(3) Since the absorbing diaphragm 22 is made of stainless steel, the stainless steel has marketability and good corrosion resistance, so that a pressure measuring device with good corrosion resistance can be obtained.

In the above embodiment, the absorption diaphragm 22 is described as being made of a metal material. However, the invention is not limited to this. For example, a vinyl material or a rubber material may be used.
In short, any material can be used as long as it can absorb a change in volume due to a change in the volume of air in the ventilation hole due to a change in the use environment temperature and a change in the atmospheric pressure.

If the absorbing diaphragm 22 is made of a vinyl material, the vinyl material has marketability and can be obtained at a low cost, so that an inexpensive pressure measuring device can be obtained. If the absorption diaphragm 22 is made of a rubber material, the rubber material has good elasticity, and can easily absorb the volume change of the air in the vent hole 15, and a pressure measuring device with good characteristics can be obtained.

It should be noted that the foregoing description has been directed to specific preferred embodiments for the purpose of illustration and illustration of the invention. Therefore, the present invention is not limited to the above-described embodiments, and includes many more modifications without departing from the spirit thereof.
This includes deformation.

[0028]

As described above, according to the first aspect of the present invention,
According to the above, the following effects are obtained. (1) An absorption diaphragm which is provided in a ring shape by sealing the absorption diaphragm chamber and the outside and which absorbs a volume change due to a change in the volume of air in the ventilation hole due to a change in the use environment temperature and a change in the atmospheric pressure is provided. Therefore, with a simple configuration, it is possible to prevent rainwater, corrosive gas,
A pressure measuring device capable of performing stable pressure measurement can be obtained.

(2) An absorption diaphragm which is provided in a ring shape by sealing the absorption diaphragm chamber and the outside and absorbs a volume change due to a change in the volume of air in the ventilation hole due to a change in a use environment temperature and a change in atmospheric pressure. Is provided, a simple product design becomes possible with a simple configuration, and an inexpensive pressure measuring device can be obtained.

According to the second aspect of the present invention, the following effects can be obtained. Since the absorption diaphragm is made of stainless steel, the stainless steel has marketability and good corrosion resistance, so that a pressure measuring device with good corrosion resistance can be obtained.

Therefore, according to the present invention, it is possible to prevent intrusion of rainwater, corrosive gas, dust and the like with a simple configuration, to perform stable pressure measurement, and to realize an inexpensive pressure measurement device.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a main part configuration of an embodiment of the present invention.

FIG. 2 is a perspective view of FIG.

FIG. 3 is an explanatory diagram of a configuration of a main part of a conventional example generally used in the related art.

FIG. 4 is a detailed explanatory view of a main part of FIG. 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sensor chip 2 Concave part 3 Measurement diaphragm 4 Semiconductor pressure detection element 5 Glass support substrate 6 Reference pressure chamber 7 Communication hole 8 Main body 9 Pouring wire 11 Signal extraction pin 12 Sealing glass 13 Hermetic seal terminal 14 Seal diaphragm 15 Vent hole 16 Amplifier case 17 O-ring 21 Absorption diaphragm chamber 21 Absorption diaphragm 101 Filled liquid P0 Atmospheric pressure P1 Measurement pressure

Claims (2)

[Claims] 1. A main body in which a measurement diaphragm is incorporated, a reference pressure chamber provided on one surface side of the measurement diaphragm to which atmospheric pressure is applied, and a communication between the reference pressure chamber provided in the main body and the outside. A pressure measuring device having a ventilation hole, an absorption diaphragm chamber provided in the main body in a ring shape and communicating with the ventilation hole, and a ring-shaped sealing room for the absorption diaphragm chamber and the outside. A pressure measuring device comprising: an absorbing diaphragm for absorbing a volume change caused by a change in the volume of air in the ventilation hole due to a change in temperature and a change in atmospheric pressure. 2. The pressure measuring device according to claim 1, wherein said absorbing diaphragm is made of stainless steel.