JPS6256819A - Measuring instrument for flow rate of gas - Google Patents

Abstract

PURPOSE:To find the imperfection of the fitting part of a tapered tube and a gas leak in the early stage by forming an observation window in a housing which contains the tapered tube and a gas leak sensor hermetically so as to observe a float for gas flow rate measurement visually. CONSTITUTION:The float 2a in the tapered tube 2 and scale 2b of a gas flow rate measuring instrument 1 are observed visually from outside the sealed housing 3 through a glass plate 4 to measure the flow rate of gas. If the fitting part of the tapered tube 3 is not perfect or if the gas leaks owing to the cracking of the tapered tube 2, a gas leak detection sensor 7 detects that and an alarm 8 drives an alarm buzzer to sound.

Description

[Detailed Description of the Invention] [Industrial Applications] This invention prevents gas from leaking to the outside from a transparent tapered tube equipped with a float for measuring the pH of the gas flow. The present invention relates to a device for measuring gas flow rate 1:1.

[Prior Art] Conventionally, for example, a 1 ft flow of various gases used in a thin film forming apparatus for silicon oxide, silicon nitride, etc. is achieved by placing a glass tapered tube in a part of the gas flow path and using this tapered tube. A float is placed inside the tube, and the gas flow 11 passing through the Taber tube is measured at the position of the float.

[Problems to be Solved by the Invention] However, such conventional gas flow rate 111i1
11+ equipment, if the tapered pipe is installed incorrectly or if the tapered pipe cracks, gas may leak to the outside.
If the gas is flammable or combustible, this can lead to an extremely dangerous situation.

[Objective of the Invention] The object of the present invention is to solve such conventional problems, and the problem is that when installing a tapered pipe, gas leaks out due to defects in the parts or cracks in the tapered pipe. Preventing 11-
1. To provide a gas flow (11 total 4 (11 devices) that can detect gas leaks at an early stage.

[L stage for solving the problem] The first stage of the present invention for achieving such purpose is to use a transparent tapered pipe equipped with a float for sipping the gas flow; A leakage detection sensor, and a sealed body that seals the tapered pipe and the gas leakage detection sensor, and the sealed casing includes a gas that hits a monitoring window for visually monitoring the float described in 1-1. Stream 1,1 is in a total of 1illll equipment.

[Operations] The gas flow control device configured in this way has a tapered tube that is installed so that even if gas leaks due to a defect in the part or the tapered tube cracks, the gas will not leak inside the body. Gas does not leak to the outside of the sealed casing only when it is filled.Then, the gas leak detection sensor detects the gas inside the sealed casing.Furthermore, the float, which produces a total of 6t11 of gas flow 111, is connected to the sealed casing by the monitoring window. 11 Vision from the outside of the body 1.: Able to see at the knee.

[Example 7] Hereinafter, with reference to the drawings, 7k of the gas in this invention will be explained.
An example of the ill measuring device will be explained below.

FIGS. 1 and 2 show the flow of the FF system: 1 L + i 1 sub-device 1. FIG. Is it the same in the figure? Those with a bow indicate the same thing.

As shown in FIG. 1, this gas flow lit +i E
7111 'kU Flow in tapered pipe 2)2
The flow of gas (monon run gas) passing through the inside of the float tube 2 is measured at the positions of floats 2 i and i, and the tapered tube 2 is equipped with I-1. 21) is formed.

This tapered tube 2 is hermetically sealed in a sealed housing 3, and this sealed housing 3 has floats 2a, ! :] 1 plate 2b [1] A transparent glass plate 4 as a monitoring window for visual monitoring d'--And this glass plate 4 is attached to the main body of the sealed casing 3 with bolts 5.

Then, the gap between the main body of the sealed casing 3 and the glass plate 4 is closed with an O-ring 6 (see FIG. 2) serving as a nuru shrine.

Further, this sealed casing 3 has a gas leak detection sensor 7. This gas leak detection sensor 7 is a semiconductor whose tip is made of tin oxide, and is used by heating this ``I'' conductor to about 350 degrees Celsius with a heater. When flammable gas absorbs blue〉1',
The resistance of the conductor decreases, the current increases, and the voltage becomes h5=I'
It is supposed to be done.

This gas leak detection sensor 7 is connected to an alarm 8. The gas leak detection sensor 7 is installed in the sealed housing 3.
The gap between the main body of the sealed casing 3 and the gas leak detection sensor 7 is also secured by an O-ring 10 (
See Figure 2! 1 (1).

Now, this gas flow jjl: As shown in FIG. It flows out into the gas pipe 12 through the tapered pipe 2 .

Note that 13 is a needle valve that stops the gas flowing from the gas pipe 11 to the tapered pipe 2 and adjusts the flow iit.

Then, the gap between the main body of the sealed casing, the ij space pipe LL12, and the needle valve 13 is also closed with the sealing material.

The gas flow IF1 measuring device 1 configured as described above is used when measuring the normal gas flow 1 (gas flow) 1, in which the gas flowing from the gas pipe 11 into the tapered pipe 2 is connected to the float disposed inside the tapered pipe 2. 2a is set to l'2 at the fixed position of [1 fill 2b -].

The float 2a and the 1-1 stack 2[) are viewed from the outside of the sealed casing 3 through the glass plate 4. It is seen as ζ, and 1M1'' of gas flow is converted into 1 liquid and 4 rivers.

Now, when installing the tapered tube 2, if gas leaks due to a defect in the part or the tapered tube 2 breaks, it is necessary to attach the main body of the sealed casing 3 and the glass plate 4. Gas leak detection system 7. Waste pipe 11
．． Since the gaps between the valve 12 and the hinge valve 13 are each closed with an O-ring 6, 10 or other sealing material, leakage gas will not leak out of the sealed housing 3.

Then, the gas leak detection sensor 7 detects the gas inside the sealed housing 3, and the alarm 8 connected to the gas leak detection sensor 7 does not sound an alarm buzzer.

Although the embodiment 1-1 has been described above, the monitoring window may be made of a plastic plate or the like.

In addition, in the embodiment, when a gas leak occurs, the gas leak detection sensor detects this and issues an alarm +11! Although the device does not emit a single signal buzzer, it is also possible to adopt an interface mechanism that closes the valve of the gas distribution system based on the signal detected by each device.

[Effects of the Invention] As is clear from the above description, the gas flow rate measuring device of the present invention comprises: a transparent tapered tube provided with a float for measuring the gas flow rate; a gas drowning detection sensor; The gas leak detection sensor is equipped with a sealed casing that seals the gas leak detection sensor, and the sealed casing has a monitoring window for visually monitoring the float described in item 11. It can prevent gas from leaking to the outside in the event of a gas leak, and can detect gas leaks early.

[Brief explanation of the drawing]

FIG. 1 shows the gas flow rate 1, L al1 in this invention.
FIG. 2 is a +E side view showing an embodiment of one device, and FIG. 2 is a -ffl<notch side view of FIG. 1. 1... Gas flow fNI, , i I sub-device, 2...
... Tapered pipe, 3 ... Sealed casing, 4 ... Brass plate, 7 ... Gas leak detection sensor, 8 ... Alarm.

Claims (2)

[Claims] (1) A transparent tapered tube equipped with a float for measuring the flow rate of gas, a gas leak detection sensor, and a sealed casing that seals the tapered tube and the gas leak detection sensor, and the sealed casing includes the A gas flow rate measuring device characterized by having a monitoring window for visually monitoring a float. (2) The tapered tube is made of glass with a scale, the monitoring window has a transparent glass plate, and the mounting portion between the main body of the sealed casing and the glass plate and the gas leak detection sensor is sealed with a sealing material. 2. The gas flow rate measuring device according to claim 1, wherein the device is hermetically sealed.