JPH04408Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a small pressure regulator for carbon dioxide gas for reducing high pressure carbon dioxide gas to a desired working pressure.

<Prior art> Generally, when carbon dioxide gas is decompressed from a high pressure to a low pressure, the decompression side is excessively cooled due to adiabatic expansion of the carbon dioxide gas, producing dry ice, which freezes and blocks the passage on the depressurization side. There is a risk.
Especially in pressure regulators for carbon dioxide gas at 50/min or more, freezing phenomenon on the decompression side cannot be avoided.
The main body of the pressure regulator is equipped with a heater and heat absorbing fins.

By the way, even in a small carbon dioxide pressure regulator for so-called low pressure use, where the usage flow rate is 20/min or less and the maximum usage pressure is 3Kg/ ^cm2 ,
As with the large-sized model, the pressure regulator body was equipped with a heater and heat-absorbing fins.

<Problems to be solved by the invention> However, as shown in FIG. 2 and FIG. As a result, the size of the pressure regulator itself becomes large, which not only makes handling work troublesome, but also the attached parts of the pressure regulator become a hindrance after piping is installed. Furthermore, a heater 50 or an endothermic fin 5
2, the manufacturing cost of the pressure regulator increases.

<Means for solving the problem> The configuration of the present invention is to provide a pressure regulator main body with a primary inlet and a secondary outlet for carbon dioxide gas, and to provide a communication path between the inlet and the outlet of the main body with a primary inlet and a secondary outlet of the carbon dioxide gas. a valve seat biased toward the valve seat by a compression spring; a diaphragm disposed across the valve seat in a position opposing the valve seat and biased toward the valve seat by a compression spring on the secondary side; A small pressure regulator for carbon dioxide gas comprising a valve connecting pin supported by a valve seat or a diaphragm and having a free end passing through a perforated hole in the valve seat and coming into contact with the diaphragm or the valve seat. It is characterized in that an insertion rod supported by the diaphragm and having a smaller diameter than the gas extraction passage is inserted on the diaphragm side of the gas extraction passage that communicates the space on the diaphragm side with respect to the seat and the secondary outlet.

<Function> Since the support part of the diaphragm is in contact with the atmosphere, it has a good heat absorption effect, and the diaphragm is thin and has good heat transfer, so when adjusting the pressure of carbon dioxide gas with a small regulator, that is, when reducing the pressure, the carbon dioxide Even if dry ice is generated on the decompression side due to adiabatic expansion of gas, the atmospheric temperature is absorbed by the diaphragm in turn, so that Dry ice no longer exists near the surface. This makes it difficult for dry ice to flow into the gas extraction passage. Further, since the insertion rod also vibrates together with the diaphragm which frequently vibrates when adjusting the pressure of carbon dioxide gas, the inflow of dry ice into the gas extraction passage and the adhesion of dry ice are prevented. Therefore, freezing of the carbon dioxide flow path does not occur.

<Example> Hereinafter, the present invention will be explained in detail with reference to the illustrated example.

In FIG. 1, reference numeral 1 denotes a pressure regulator main body, in which a primary side inlet 101 for supplying carbon dioxide gas and a secondary side outlet 102 for taking out carbon dioxide gas reduced to a desired pressure are appropriately communicated. . 2 is a valve seat having a drilled hole 201 in the center, and 3 is a valve seat that is slidable in the Z direction, and is biased in the Z ₂ direction by a compression spring 4 on the primary side. 5 is a diaphragm disposed across the valve seat 2 at a position facing the valve seat 3; in the case shown, the pressure regulator main body 1;
It is clamped by a cover 8 which is screwed onto the pressure regulator main body 1. The diaphragm 5 is integrally formed with a spring receiver 6 and a metal fitting 7 that is screwed onto the spring receiver 6. Reference numeral 9 denotes a pressure adjustment screw that is screwed onto the cover 8. By operating this pressure adjustment screw, the biasing force of the diaphragm in the _Z1 direction is applied via the spring receiver 11, the secondary side compression spring 12, and the spring receiver 6. be adjusted. Reference numeral 13 denotes a valve communication pin that is integrally supported by, for example, the valve seat 3. The valve communication pin 13 passes freely through the perforated hole 201 of the valve seat 2, and its free end abuts against the diaphragm 5 side. 1
Reference numeral 4 denotes a gas extraction passage communicating with the secondary side outlet, and the open end 141 of this gas extraction passage 14 in the Z ₂ direction, that is, the gas extraction port, is connected to the diaphragm 5 with respect to the valve seat 2.
It is arranged at a position close to the diaphragm 5 in the side space. Of course, the outlet 141 is arranged at a position where it does not come into contact with the diaphragm 5 when the diaphragm 5 moves up and down. An insertion rod 15 is supported by the diaphragm 5 and inserted into the gas extraction passage 14, and is inserted into the gas extraction passage 14 as appropriate so that the desired flow rate of carbon dioxide gas is obtained despite the presence of the insertion rod 15. The dimensions with respect to the rod 15 are determined. Note that the space B formed when the valve seat 2 and the valve seat 3 are in contact with each other is appropriately communicated with the primary side inlet 101.

In the above, for example, the primary side inlet is connected to a high-pressure welding carbon dioxide cylinder, and the secondary side outlet is connected to an arc welding torch.

By the way, the flow rate and pressure of carbon dioxide gas used during arc welding are approximately 15/min and 1.5/min, respectively.
~2.5Kg/cm ² , so the pressure regulator may be small. Operate the pressure adjustment screw 9 of this small pressure regulator to adjust the secondary pressure to the desired value, for example 2.5.
Adjust so that it is Kg/cm ² . The state in which the high-pressure carbon dioxide gas connected to the primary side inlet is decompressed to the desired working pressure, that is, the set secondary pressure, and taken out from the secondary side outlet is the same as that of a known pressure regulator, so a description thereof will be omitted.

Now, when high-pressure carbon dioxide gas flows into space A through valve seat 3 and valve seat 2, that is, when the pressure is reduced from high pressure to low pressure, the reduced pressure side is excessively cooled due to adiabatic expansion of carbon dioxide gas, and dry ice is generated. do.

By the way, the diaphragm 5 is thin and has good heat transfer, and since the supporting portion of the diaphragm 5, that is, the cover 8 is in contact with the atmosphere, the diaphragm 5 has a good heat absorption effect. For this reason, when the dry ice comes into contact with the diaphragm 5, the diaphragm 5 tends to be excessively cooled, but since the diaphragm 5 has a good heat absorbing effect against atmospheric temperature as described above, the diaphragm 5 and the insertion rod 15 are It is never cooled. Of course, this condition depends on the amount of dry ice generated, but for example, secondary pressure (maximum): 3, which is the subject of this invention.
Kg/cm ² , operating flow rate (maximum): 20/min In so-called small pressure regulators for carbon dioxide gas, even if dry ice is generated, the surfaces of the diaphragm 5 and the insertion rod 15 are frozen. I didn't. Further, dry ice no longer exists near the surface of the diaphragm 5, which has a good heat absorption effect at atmospheric temperature, and near the surface of the insertion rod 15 supported by the diaphragm 5 and inserted into the gas extraction passage 14. This makes it difficult for dry ice to flow into the gas extraction passage. Further, since the insertion rod 15 also vibrates together with the diaphragm 5, which frequently vibrates when adjusting the pressure of carbon dioxide gas, the inflow of dry ice into the gas extraction passage and the adhesion of dry ice are prevented. Therefore, the freezing phenomenon of the secondary flow path of carbon dioxide gas does not occur, and carbon dioxide gas in a desired state can be used.

Note that the gas outlet 141 may be made of an appropriate material such as Teflon or ceramics to which dry ice does not easily adhere. Of course, the pressure regulator body 1 and the gas outlet 141 can also be integrated. Furthermore, if the insertion rod 15 is made of a thermally conductive material such as copper, aluminum, or an alloy thereof, the effect of absorbing heat at atmospheric temperature will be even better. Furthermore, the insertion rod 1 via the diaphragm 5
In order to improve the heat absorption effect to the diaphragm 5, the gas outlet 141 can be positioned as close to the supporting side of the diaphragm 5 as possible. Furthermore, the insertion rod 15 can also be attached directly to the diaphragm 5. Furthermore, the valve connecting pin 13 can be supported on the diaphragm 5 side and the free end can be brought into contact with the valve seat 3. In addition, the gas outlet 141
Although it is preferable that the gas outlet 141 and the diaphragm 5 be close to each other, the insertion rod 15 is provided even if the gas outlet 141 and the diaphragm 5 are separated from each other to some extent.
Inflow of dry ice into the gas extraction passage and adhesion of dry ice are reliably prevented. Of course, in order to maintain airtightness, an appropriate airtight member such as a "0" ring or packing may be provided.

<Effects of the Invention> As is clear from the above description, the present invention provides a known compact pressure regulator for carbon dioxide gas in which the gas take-off passage communicates the space on the diaphragm side with respect to the valve seat and the secondary outlet. The feature is that an insertion rod supported by the diaphragm and having a smaller diameter than the gas extraction passage is inserted into the diaphragm side, so that the small carbon dioxide pressure regulator can be formed extremely compactly and manufactured at low cost. be able to.

[Brief explanation of drawings]

FIG. 1 is a front sectional view showing an embodiment of the present invention, and FIGS. 2 and 3 are front sectional views showing conventional examples, respectively. 1...Pressure regulator body, 2...Valve seat, 3...Valve seat, 4...Primary side compression spring, 5...Diaphragm, 12...Secondary side compression spring, 13...
...Valve connection pin, 141...Gas outlet, 15
...Insertion rod, 101...Primary side inlet, 102...
Secondary exit.

Claims (1)

[Scope of utility model registration request] A pressure regulator main body is provided with a primary inlet and a secondary outlet for carbon dioxide gas, and a valve seat is provided in a communication path between the inlet and the outlet of the main body and is biased toward the valve seat by a compression spring on the primary side. A diaphragm is disposed across the valve seat and opposed to the valve seat, and is biased toward the valve seat by a compression spring on the secondary side. In a small pressure regulator for carbon dioxide gas, which is provided with a valve connecting pin that extends freely and has a free end that contacts a diaphragm or a valve seat, a gas outlet that communicates a space on the diaphragm side with respect to the valve seat and a secondary side outlet. A small pressure regulator for carbon dioxide gas, which is formed by inserting an insertion rod supported by the diaphragm and having a smaller diameter than the gas extraction passage into the diaphragm side of the passage.