JPH0138510Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field] The present invention relates to a pressure measuring device.

More specifically, the present invention relates to a pressure measuring device in which the internal chamber is partitioned into a measuring chamber and a reference chamber by a pressure receiving element, the pressure measuring device is of a single liquid chamber type, and is equipped with an attitude error compensation mechanism.

[Prior art]

FIG. 1 is a diagram illustrating the configuration of a conventional example that has been commonly used.

In the figure, 1 is a main body, and 2 is an internal chamber provided in the main body 1. 3 is a pressure receiving element provided in the internal chamber 2. In this case, the pressure receiving element 3 includes a ring-shaped support portion 31 and a measurement diaphragm 3.
2 and more. 321 is a displacement detection means provided on the diaphragm 32, and in this case, a semiconductor strain gauge is used. The internal chamber 2 is a measurement chamber 21 and a reference chamber 2 into which the reference pressure P _s is introduced by the pressure receiving element 3.
It is divided into 2. A seal diaphragm 4 is provided to cover the outer surface of the main body 1. 5
is a cover provided on the main body 1 to cover the seal diaphragm 4. The cover 5 constitutes the main body 1 and an external chamber 6. Thus, the external chamber 6 is partitioned by the seal diaphragm 4 into a pressure receiving chamber 61 into which the measurement pressure P _n is introduced and a pressure guiding chamber 62 . 7 is a communication hole connecting the measurement chamber 21 and the pressure chamber 62.
Reference numeral 8 denotes a sealed liquid that fills the measurement chamber 21, the communication hole 7, and the pressure chamber 62, and in this case, silicone oil is used.

In the above configuration, the measured pressure P _n is
, the pressure is applied to the measuring diaphragm 32 via the sealing diaphragm 4, the fill liquid 8. The measurement diaphragm 32 is the reference chamber 22
It is displaced in response to the reference pressure P _s introduced into the measurement chamber 21 and the measurement pressure P _n transmitted to the measurement chamber 21 . This displacement is
The displacement detection means 321 attached to the measurement diaphragm 32 can detect it as an electrical signal.

However, such a device has an attitude error as shown below.

Now, as shown in FIG.
and the distance between the seal diaphragm 4 and the filled liquid 8.
If the specific gravity of is p, the direction of gravity is y, the angle of inclination from the y direction is θ, and the effective area of the measurement diaphragm 32 is A _e , then the error component ΔH caused by the attitude change due to the tilt of θ is ΔH= HpgA _e sinθ.

When measuring a small pressure, for example, a pressure of 100 mmH ₂ O or less, even if the inclination angle θ is small, the above value has a large influence, resulting in a pressure measuring device with a large attitude error.

The present invention solves this problem.

[Purpose of invention]

An object of the present invention is to provide a pressure measuring device that has small posture errors and is therefore resistant to vibrations.

[Structure of the idea]

In order to achieve this purpose, an internal chamber provided in the main body, a pressure receiving element that partitions the internal chamber into a measurement chamber into which measurement pressure is introduced and a reference chamber into which reference pressure is introduced, and A first external chamber provided symmetrically around the center and partitioned into a first pressure receiving chamber and a first pressure impulse chamber by a first seal diaphragm; and a first external chamber partitioned into a second pressure receiving chamber and a second pressure impulse chamber by a second seal diaphragm. a second external chamber, a communication hole that communicates the first and second pressure chambers and the measurement chamber, and an enclosure that fills the communication hole, the first and second pressure chambers, and the measurement chamber. This is a pressure measuring device comprising a liquid and a displacement detecting means for detecting displacement of the measuring diaphragm.

Examples will be described below.

〔Example〕

FIG. 3 is an explanatory diagram of the configuration of an embodiment of the present invention.

Hereinafter, only the differences from FIG. 1 will be explained.

Reference numerals 4a and 4b denote first and second seal diaphragms that are symmetrically provided to cover the outer surface of the main body 1 and separated by a distance l from the measurement chamber 21.
5a and 5b are seal diaphragms 4, respectively.
This is a cover provided on the main body 1 to cover the parts a and 4b. The covers 5a and 5b constitute the main body 1 and first and second external chambers 6a and 6b, respectively.
The first and second external chambers 6a and 6b are pressure receiving chambers 61a and 61 into which the measurement pressure _Pn is introduced by the first and second seal diaphragms 4a and 4b, respectively.
b, and pressure chambers 62a, 62b. 7
A is a communication hole connecting the measurement chamber 21 and the pressure chamber 62a. 7b is a communication hole connecting the measurement chamber 21 and the pressure chamber 62b. 8a is the measurement chamber 21 and the communication hole 7a,
7b and the pressure chambers 62a and 62b.

The operation of the above configuration will be explained.

As shown in FIG. 4, when the device is tilted by θ degrees from the y direction, the pressure chambers 62a, 62b and the communication hole 7
Since a and 7b are located at symmetrical positions with respect to the measurement chamber 21, the head error is canceled and no posture error occurs.

In the above-mentioned embodiments, a semiconductor strain gauge type pressure measuring device was described, but the present invention is not limited to this. For example, a capacitance type pressure measuring device or a differential coil type pressure measuring device may be used. In short, any one-liquid fixed pressure measuring device may be used.

[Functions and effects of the idea]

As explained above, in the present invention, the pressure receiving portions are arranged symmetrically with respect to the pressure detection mechanism, so that head errors due to differences in the heads of the sealed liquid are prevented from occurring.

As a result, according to the present invention, it is possible to realize a pressure measuring device that has small posture errors and is therefore resistant to vibrations.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of the configuration of a conventional example that has been commonly used in the past, Fig. 2 is an explanatory diagram of the operation of Fig. 1, Fig. 3 is an explanatory diagram of the configuration of an embodiment of the present invention, and Fig. 4 is FIG. 3 is an explanatory diagram of the operation of FIG. 3; 1... Main body, 2... Internal chamber, 21... Measurement chamber,
22...Reference chamber, 3...Pressure receiving element, 31...Support part, 3
2...Measuring diaphragm, 321...Displacement detection means,
4a, 4b...Seal diaphragm, 5a, 5b...
Cover, 6a, 6b...External chamber, 61a, 61b...
Pressure receiving chamber, 62a, 62b...pressure chamber, 7a, 7b...
Communication hole, 8...Filled liquid.

Claims (1)

[Scope of utility model registration request] an internal chamber provided in the main body; a pressure receiving element that partitions the internal chamber into a measurement chamber into which measurement pressure is introduced and a reference chamber into which reference pressure is introduced; and a first pressure receiving element provided symmetrically around the measurement chamber. a first external chamber partitioned into a first pressure receiving chamber and a first pressure impulse chamber by a seal diaphragm; a second external chamber partitioned into a second pressure receiving chamber and a second pressure impulse chamber by a second seal diaphragm; A communication hole that communicates the first and second pressure chambers with the measurement chamber, a sealed liquid that fills the communication hole, the first and second pressure chambers, and the measurement chamber, and displacement of the measurement diaphragm. A pressure measurement device comprising displacement detection means for detecting.