JPS63255616A - Flow rate converter - Google Patents

Abstract

PURPOSE:To provide various measuring ranges and to measure a large flow rate, by providing the hole constituting a throttle for a bypass passage in addition to the hole constituting a measuring throttle and providing a cantilevered beam pressure accepting plate in opposed relation to said hole. CONSTITUTION:The hole 201 constituting a throttle for a bypass passage is provided with respect to the hole 107 constituting a flow rate measuring throttle and the extending part of a cantilevered beam pressure accepting plate 200 is opposed to said hole 201 to mount said plate 201 to a half body 101B. The extending part 104A of a cantilevered beam pressure accepting plate 104 for measurement is provided in opposed relation to the hole 107. Further, the displacement detection coils 112A, 112B constituting a displacement detector are provided in opposed relation to the pressure receiving plate 104 and connected to a bridge to take out the displacement quantity of the extending part 104A on the side especially opposed to the hole 107 of the pressure accepting plate 104 as the inductance change of the coil 112A. Then, the electric signal corresponding to the flow rate of the gas passing through the hole 107 is extracted from the change quantity of inductance.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a flow rate conversion device for measuring the flow rate of, for example, gas.

``Prior Art'' The present applicant proposed a flow rate conversion device in ``Japanese Patent Application No. 61-6958'', and this invention relates to an improvement of this earlier application.

The structure of the previously proposed flow rate detector will be explained using FIGS. 2 and 3.

FIGS. 2 and 3 show the structure of the previously proposed flow rate conversion device. In the figure, 101 indicates a body. The body 101 is constructed by combining body halves 101A and 101B with ports 1-102.

A vacant space 103 is located at the joint between the body halves 101A and 101B.
is formed, and a cantilever pressure receiving plate 10 is installed in this empty space 103.
Attach 4. The cantilever pressure receiving plate 104 is made of a magnetic material with spring properties, has a rectangular shape as shown in FIG. Extend from one side to the other around the fixed position.

One extension portion 104A is arranged to face the hole 107 formed in the body half 101B. In this example, a hole 107 formed in the body half 10'lB is used as a fluid inlet, and a hole 108 formed in the body half 10]A is used as a fluid outlet. The hole 07 constituting the inlet port constitutes a kind of throttle, and allows the fluid that has passed through the throttle to hit the plate surface of one extension 104A of the cantilever pressure receiving plate 104 perpendicularly.

A side wall 109 is provided on the side edge of the extension part 104A in order to effectively apply the force exerted by the fluid flow to the cantilever pressure receiving plate]04, and a wall 111 is also provided at a position facing the tip of the extension part 1.04A. The wall]] 1 has a notched shape on the upper side, and has a wall surface shape that obtains a displacement conversion output proportional to the flow rate, and functions to linearize and correct the output.

In this example, the displacement detection coil 11 constitutes a displacement detector under the extension part 104A and the other extension part 104B.
2A and 112B are provided. These detection coils, 112
A and ]]2B can use, for example, a coil wound around an E-shaped core. As the facing distance with the beam pressure receiving plate 104 changes, the inductance of the displacement detection coils 11.2A and 112B changes, and the amount of displacement of the cantilever pressure receiving plate 104 can be determined.

The coils 112 and 112B constitute a bridge 113 with resistors 114, 115, and 1.16 as shown in FIG. Beam pressure plate 1.0
When the extension part 104 of 4 is displaced, the inductance of the detection coil 112A changes, and the amount of change is measured by the bridge 113.
It can also be extracted as a detection signal. bridge 11
The detection signal taken out from the detector 3 is converted into direct current by a detection-rectifier circuit 118, outputted through a linearizer 119 as required, and inputted to an indicator 121 or the like.

Note that the reference numeral 122 shown in FIG. 2 indicates a stopper that protects the cantilever pressure receiving plate 104, and when excessive fluid pressure is applied,
This stopper 122 receives the cantilever pressure receiving plate 104 and prevents the cantilever pressure receiving plate 104 from being permanently deformed. The stopper 122 also extends to the extended portion 104B side of the cantilever pressure receiving plate 104, and covers and protects the extended portion 104B side.

In the examples shown in Figures 2 and 3, the cantilever pressure receiving plate 1 for flow rate detection is
A case is shown in which a pseudo pressure receiving plate 123 is provided separately from 04. This pseudo pressure receiving plate 123 is connected to the detection coil 124A and 1.2/
Both extensions 123A, by I 13.

123B is detected, and this displacement detection signal is sent to the fourth
A difference signal is obtained by the bridge circuit 128 and the operational amplifier 129 shown in the figure, and the voltage controlled oscillator 117 is controlled by this difference signal to control the pressure receiving plate 104 according to the posture of the body], O].
This is provided to compensate for the influence of gravity on the body.

[Problems to be Solved by the Invention] According to the structure of the flow rate conversion device proposed earlier, in order to create devices with different flow rate measurement ranges, a large number of magnetic spring materials with different spring constants for the cantilever pressure receiving plate 104 are prepared. This has the disadvantage of increasing costs when producing a wide variety of products in small quantities.

In addition, to obtain a flow rate converter that can measure large flow rates, hole 1 is required.
I have to make the diameter of '07 thicker (・.

In order to make the hole 107 thicker so that proper measurements can be made, the width of the pressure receiving plate 10'40, etc. must also be increased, which has the disadvantage that the shape of the body 101 must also be increased. .

The purpose of this invention is to create a flow rate conversion device that has various measurement ranges without having to prepare various spring materials for use in the cantilever pressure receiving plate, and also to provide a flow rate conversion device that can measure large flow rates. An object of the present invention is to provide a flow rate conversion device having a structure that can be made compact.

"Means for Solving the Problem" In this invention, at least two throttles are provided in the flow path, and a cantilever pressure receiving plate is provided on the downstream side of each of the throttles. A variable orifice is configured to bypass the flow of fluid, and a flow rate measuring section is configured by the other restrictor and a cantilever pressure receiving plate.

According to the configuration of the present invention, since a bypass path is provided for the measuring section, a flow rate conversion device having various measurement ranges can be made by simply changing the bypass amount of the bypass path.

Therefore, it is not necessary to prepare magnetic spring materials of various thicknesses to be used as the cantilever pressure receiving plate, so that costs can be reduced even when producing a wide variety of products in small quantities.

In addition, by changing the cross-sectional area of the hole on the bypass side, it is possible to create a flow rate converter with different measurement ranges, so even when creating a flow rate converter for measuring large flow rates, it is only necessary to increase the cross-sectional area of the hole on the bypass side. This provides the advantage of not having to increase the size of the body.

"Embodiment" FIG. 1 shows an embodiment of the present invention. In the figure, parts corresponding to those in FIGS. 2 and 3 are denoted by the same reference numerals, and redundant explanation thereof will be omitted, but this example does not show the case where the body 101 has a rectangular shape. In this invention, a hole 201 constituting a bypass passage constriction is provided for the hole 107 constituting a flow rate measurement constriction, and the extended portion of the cantilever pressure receiving plate 200 is opposed to this hole 201, so that the body half It is attached to the body 101B.

The extension portion 104A of the cantilever pressure receiving plate 105 for measurement is provided to face the hole 107 constituting the measurement diaphragm, as described above. In addition, this cantilever pressure receiving plate], a displacement detection coil which constitutes a displacement detector opposite to 04] 12A]
12B are provided, and these displacement detection coils 1]2 people]]2
B is connected like the bridge 113 explained in FIG. An electrical signal corresponding to the flow rate of gas passing through the hole 107 is extracted from the amount.

Side walls 109 and 111 are provided surrounding the extension portion 104A of the cantilever pressure receiving plate 10jI in a U-shape, so that the fluid can flow through the cantilever beam 10.
4 extension F$ 104 so that it acts effectively on A (・ru.

Note that this example shows an example in which the pseudo pressure receiving plate 123 shown in FIG. 3 is not necessarily used, since it is not necessarily necessary.

"Effects of the Invention" As explained above, according to the present invention, in addition to the hole 107 constituting the measuring aperture, there is also a hole 201 constituting the diaphragm for measuring), and a cantilevered beam facing the hole 201. Pressure receiving plate 2
Since 00 is provided, the absolute amount of fluid can be increased by the amount of fluid that passes through the throttle. The ratio of the amount of fluid passing through the bypass aperture and the amount of fluid passing through the measurement aperture is determined mainly by the area ratio of the holes 201 and 107 and the cantilever pressure receiving plate 20.
It is determined by spring constants of 1 and 200.

Therefore, by determining the ratio of the flow rates of the throttle 201 and 1.07 in advance, the total fluid flow rate can be determined from the amount of displacement of the cantilever pressure receiving plate 104.

The measurement range can be easily changed by changing the area of the via hole 201.

Therefore, the measurement hole 107 and the cantilever pressure receiving plate], No. 04 (
Flow rate conversion devices with different measurement ranges can be made without changing constants, etc.

Therefore, according to the present invention, it is possible to create a flow rate conversion device with different measurement ranges without having to prepare a cantilever pressure-receiving plate], 04, and magnetic plate members having various plate thicknesses and various plate constants. This enables high-mix, low-volume production at low cost.

Furthermore, since the bypass hole 201 is not a hole specifically for flowing a measurement fluid, its shape may be arbitrarily selected. Therefore, a hole with a large cross-sectional area can be easily formed, so that the shape of the body half 101B does not need to be enlarged. Therefore, even when making a flow rate converter with a large measured flow rate, the body halves 1. There is also the advantage that there is no need to increase the size of OI B and it can be made smaller.

Further, in this invention, a cantilever pressure receiving plate 200 is provided in the bypass hole 201, and the bypass passage also operates as a variable orifice by means of the cantilever pressure receiving plate 200.
Therefore, the flow path is narrowed on the low flow rate side, and the flow path is opened on the high flow rate side, resulting in the advantage that a wide linear measurement range can be obtained.

In addition, in the above description, the detection coil 11.2A is used as the displacement detector.

112B has been described, however, it is also possible to measure the displacement amount of the cantilever pressure receiving plate using an electrostatic 9-quantity method.

[Brief explanation of drawings]

Fig. 1 is a plan view showing an embodiment of the present invention, Fig. 2 is a sectional view for explaining the prior art, Fig. 3 is a plan view for explaining the prior art, and Fig. 4 is a plan view for explaining the prior art. FIG. 3 is a connection diagram for explaining the electrical structure. 101 A, 101]'3: Half body, 104
．． 200: Cantilever pressure receiving plate, 107: Hole forming a measurement aperture, 112A, 112B: Detection coil forming a displacement detector, 201: Hole forming a bypass aperture.

Claims (1)

[Claims] (1) A: at least one pair of throttles provided in the channel through which the fluid flows, and B: at least two throttles provided downstream of the throttles and arranged so that the fluid that has passed through the throttles hits the plate surface in a direction substantially perpendicular to the plate surface. A flow rate conversion device comprising: (C) a cantilever-shaped pressure receiving plate; and (C) a displacement detector that is provided opposite to one of the pressure receiving plates and measures the amount of displacement of the pressure receiving plate.