JP2596875B2 - Welding safety device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a safety device for welding, and more particularly to a safety device used for gas welding.

[0002]

2. Description of the Related Art Conventionally, as a safety device on a combustion gas side such as acetylene gas used for gas welding, when an oxygen gas or a mixed gas of oxygen-acetylene flows back to an acetylene gas side in a combustion or non-combustion state. It is known that a backflow is prevented, and when the flow returns to a normal flow, the normal flow is prevented.

[0003]

In the above-mentioned welding safety device, valve means are separately used as means for preventing backflow and normal flow, so that the structure is complicated and the assembly is not easy. Large overall dimensions and high manufacturing costs.

An object of the present invention is to provide a means for preventing backflow and normal flow, which is simple and easy to assemble, is compact as a whole, and has a low manufacturing cost.

[0005]

In order to achieve the above object, in the welding safety device according to the present invention, as a means for preventing backflow and normal flow, an airtight surface for preventing backflow and an airtight surface for preventing normal flow are provided. The common packing is configured to contact in an airtight manner.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below with reference to the drawings.

A cylindrical main body (2) having a combustion gas flow path (1) is connected to a main body (4) having an integral joint (3) at one end and a screw (5) to the main body. (6). The joint part (3) is connected to a pipe or the like on the combustion gas supply side by an external thread (7), and the joint part (6) is connected to a pipe or the like on the welding tool by an external thread (8). You. In a normal flow state, the combustion gas flows in from the joint portion (3) and flows out from the joint portion (6) as shown by an arrow A.

[0008] Valve means for preventing gas backflow and normal flow are incorporated in the flow path of the main body (4). The valve body (9) of this valve means is reciprocally inserted into the guide tube (10), and the guide tube (10) is incorporated in the flow passage of the main body (4). A filter (11) made of a sintered metal or the like that prevents passage of flashback is provided on the outer periphery of the guide cylinder (10) by a seat (12). Both normal flow and reverse flow gases are guided through the filter (11) at the seat (12).

The valve means is constructed in various modes.
The first embodiment is shown in FIGS. The valve body (9) is composed of a small diameter portion (13) and a large diameter portion (14). The small-diameter portion (13) has a first packing (16), which is made of rubber and has an annular shape and is commonly used to prevent normal flow and backflow, in one annular groove (15) on the outer periphery thereof, and the other packing (16). Annular groove (1
Similarly, in FIG. 7), a second packing (18) for preventing backflow of an abnormally high pressure, such as at the time of an explosion, is fitted and fixed to each other in a rubber-like annular shape. Airtight surface (19) for preventing backflow, airtight surface (20) for preventing normal flow, and airtight surface (21) for preventing backflow of abnormally high pressure at the time of explosion, in contact with these packings (16, 18) in an airtight manner. Are formed in an annular raised portion (22) raised in the inner peripheral surface of the joint portion (3). The small diameter portion (13) further has a ventilation hole (23) for communicating the inside and outside thereof to guide a normal flow from the outside to the inside of the valve body (9).

In FIG. 1, the valve element (9) is pushed to the right at a normal flow pressure and is opened. The normal flow flows in from the joint part (3), passes between the airtight surface (19) and the packing (16), and flows into the valve body (9) from the vent hole (23) of the valve body (9). . The normal flow flowing out of the valve body (9) passes through the filter (11) from the inside to the outside, flows to the back of the seat (12), and flows out of the joint (6).

When a backflow of a relatively low pressure that does not reach the high pressure at the time of the explosion occurs, the valve element (9) is pushed to the left as shown in FIG. Contact airtightly to prevent backflow.

When an explosion occurs and a backflow accompanied by a backfire occurs, the filter (11) blocks the passage of the backfire. At this time, an abnormally high backflow pressure causes the valve (9) to move the valve body (9) as shown in FIG. And push it further to the left. The valve element (9) stops when its tip engages the shoulder (24) of the joint (3). During this time, the packing (16) moves from the airtight surface (19) to the airtight surface (20) through the airtight surface (21), and the packing (18) is
It moves to the position where it comes into airtight contact with (21). The packing (18) also prevents abnormal high-pressure backflow.

When the backflow pressure is released due to the breakage of the hose and the normal flow acts on the valve element (9), the valve element is pushed rightward as shown in FIG. It contacts the airtight surface (20) to prevent outflow of normal flow.

In order to return the valve body (9) to the initial position where backflow can be prevented, the valve body is pushed in with a rod-like member, and the packing (16) is moved from the airtight surface (20) to the airtight surface (19). Airtight side
Move (21) around.

FIG. 5 shows a second embodiment of the valve means.
As shown in FIG. This valve means is different from that of the first embodiment in that one third packing (25) prevents the flow of a low backflow pressure from an abnormally high backflow pressure and a normal flow pressure. The packing (25) is also made of rubber and has an annular shape, and is fitted and fixed in the annular groove (15) of the small diameter portion (13) of the valve body (9). An annular bulge in which a low-pressure backflow-preventing airtight surface (27) and a normal-flow-preventing airtight surface (28) in airtight contact with the packing (25) are raised inside the inner peripheral surface of the joint part (3). It is formed on both side surfaces of the portion (30). An airtight surface (31) for preventing backflow of an abnormally high pressure generated during an explosion is formed on the inner peripheral surface of the joint (3) connected to the airtight surface (28).

In FIG. 5, the valve body (9) is in a valve-open state in which it is pushed rightward at a normal flow pressure. Normal flow is first
As in the embodiment, it flows in from the joint part (3) and flows out from the joint part (6).

When a relatively low-pressure backflow without explosion occurs, the valve body (9) is pushed to the left as shown in FIG. 6, and the packing (25) comes into contact with the airtight surface (27), and the backflow occurs. To block.

When a backflow accompanied by flashback occurs due to the explosion, the backflow is blocked by the filter (11) in the same manner as in the first embodiment, but an abnormally high backflow pressure causes the valve body (9) to flow. Push it further to the left as shown in FIG. The valve element (9) stops when its tip and the shoulder (24) of the joint (3) engage. Meanwhile, the packing (25) moves from the airtight surface (27) to the airtight surface (31) through the raised surface (32) of the annular ridge (30), and moves to the airtight surface (3).
Contact with 1) to prevent backflow of abnormally high pressure.

When the backflow pressure is eliminated due to the breakage of the hose, the valve body (9) is pushed rightward as shown in FIG. 8 at a normal flow pressure, and the packing (25) comes into contact with the airtight surface (28). To prevent the outflow of the normal flow.

In order to return the valve body (9) to the initial position, the valve body is pushed rightward with a rod-like one as in the first embodiment.

As the third embodiment of the valve means, FIGS.
As shown in FIG. This valve means has one fourth packing (33)
The second embodiment is the same as that of the second embodiment in preventing the flow of the abnormally high backflow pressure and the normal backpressure from the low backflow pressure, but differs in the following points. An annular rubber packing (33) is fitted and fixed in an annular groove (34) on the inner peripheral surface of the joint portion (3). An airtight surface (35) for preventing backflow of low pressure and a gastight surface (36) for preventing normal flow in contact with the packing (33) are provided on both sides of an annular ridge (37) raised on the outer peripheral surface of the valve body (9). Formed on the surface. An airtight surface (38) for preventing abnormal high-pressure backflow generated at the time of the explosion is formed on the peripheral surface of the annular groove of the valve body (9) connected to the airtight surface (36).

In FIG. 9, the valve element (9) is in an open state at a normal flow pressure as in the first and second embodiments.
Normal flow also flows in from the joint part (3) and exits from the joint part (6).

When a low-pressure backflow occurs during non-explosion, the valve element (9) is pushed to the left as shown in FIG. 10, and the airtight surface (35) at the tip of the valve element (9) is packed (33). )
Prevent the backflow.

When an abnormally high pressure backflow accompanied by flashback occurs at the time of the explosion, the flashback is blocked by the filter (11) in the same manner as in the previous embodiment. It is pushed further to the left as shown in FIG. The valve body (9) stops at that position with its airtight surface (35) engaging the shoulder (39) of the joint (3). Meanwhile, the ridge (37) moves through the packing (33) and moves between the shoulder (39) and the packing (33), and the airtight surface (38) comes into contact with the packing (33) and a backflow of abnormally high pressure occurs. To block.

When the backflow pressure is eliminated, the valve element (9) is pushed to the right at normal flow pressure as shown in FIG. 12, and its airtight surface (36) comes into contact with the packing (33) to allow normal flow. Block.

In order to return the valve element (9) to the initial position, the valve element is pushed with a rod-like member as in the above-described embodiment, and the raised portion (37) is moved by passing through the packing (33). .

In the first to third embodiments, the valve element (9)
When the compression coil spring (40) is incorporated between the guide cylinder (10) and
The valve element moves as soon as any backflow pressure is generated to close the flow path.

[0028]

As described above, the present invention provides an airtight surface (19, 27, 35) for preventing backflow as a means for preventing backflow and normal flow.
And the common packing (16, 25, 33) in contact with the airtight surface (20, 28, 36) for normal flow prevention, the structure of the blocking means is simple and easy to assemble. Therefore, it is possible to make the whole compact and reduce the manufacturing cost. The present invention further provides a packing (25, 33) which is also used for preventing the backflow and the normal flow, and a packing (18) which is separate from the packing (25, 33) and moves together to prevent explosion or the like. Since it is configured to prevent the backflow of an abnormally high backflow pressure that occurs at the time of welding, the safety as a welding safety device is maintained while maintaining the effects of the above configuration, assembly, dimensions, and manufacturing costs. The function will be higher.

[Brief description of the drawings]

FIG. 1 is a partially longitudinal front view of a welding safety device showing a normal flow state in a first embodiment of the present invention.

In Figure 2 the weld safety of FIG. 1 is a vertical sectional front view partially showing the blocking state of the reverse flow.

In Figure 3 the weld safety of FIG. 1 is a vertical sectional front view partially showing the blocking state of abnormally high pressure in the reverse flow.

In Figure 4 the weld safety of FIG. 1 is a vertical sectional front view partially showing the blocking state of the normal stream.

FIG. 5 is a partially longitudinal front view of a welding safety device showing a normal flow state in a second embodiment of the present invention.

In Figure 6 the weld safety of FIG 5 is a vertical sectional front view partially showing the blocking state of the reverse flow.

In [7] welding safety of FIG 5 is a vertical sectional front view partially showing the blocking state of abnormally high pressure in the reverse flow.

In [8] welding safety of FIG 5, is part longitudinal front view showing a blocking state of normal flow

FIG. 9 is a partial longitudinal front view of a welding safety device showing a normal flow state in a third embodiment of the present invention.

In Figure 10 the welding safety of FIG 9 is a vertical sectional front view partially showing the blocking state of the reverse flow.

In [11] welded safety of FIG 9 is a vertical sectional front view partially showing the blocking state of abnormally high pressure in the reverse flow.

In Figure 12 the welding safety of FIG 9, is part longitudinal front view showing a blocking state of normal flow

[Explanation of symbols]

2 Body 9 Valve Element 10 Guide Cylinder 11 Filter 12 Receiving Seat 16 First Packing 18 Second Packing 19 Airtight Surface for Preventing Low-Pressure Backflow 20
Airtight surface for normal flow prevention 21 Airtight surface for high pressure backflow prevention 23 Vent hole 25 Third packing 27 Airtight surface for low pressure backflow prevention 28 Airtight surface for normal flow prevention
31 High-pressure backflow prevention airtight surface 33 Fourth packing 35 Low-pressure backflow prevention airtight surface 36 Normal flow prevention airtight surface 38 High-pressure backflow prevention airtight surface 40 Compression coil spring

Claims (6)

(57) [Claims] An airtight surface (19, 27) for preventing backflow , comprising: a cylindrical main body (2) having a combustion gas flow path; and a valve element (9) incorporated in the flow path of the main body. And for normal flow prevention
An airtight surface (20, 28) is formed on the inner peripheral surface of the flow path of the main body (2).
Formed on both sides of the annular ridge (22, 30),
The packings (16, 25) that contact both airtight surfaces are
The packing (1) is fixed to the outer peripheral surface of the valve body (9).
6, 25) prevents backflow due to the generation of relatively low backflow pressure
Contact with airtight surface (19, 27) to prevent backflow and explode
Due to the occurrence of abnormally high backflow due to
Airtight to prevent normal flow by passing through the inner peripheral surface of 2, 30)
Surface (20, 28) side, and with the occurrence of normal flow,
Normal flow by contacting the airtight surface (20, 28) for preventing normal flow
Safety device for preventing welding. 2. The valve element (9) according to claim 1 , wherein the packing (16) passes through the annular ridge (22) from the backflow preventing airtight surface (19) to the normal flow preventing airtight surface (20). When the main body is moved, it is stopped at that position at the shoulder (24) of the main body, and at the stop position, the airtight surface (21) of the inner peripheral surface between the two airtight surfaces (19, 20) of the raised portion (22). 2.) The welding safety device according to claim 1 , wherein another packing (18) for preventing abnormally high backflow in contact with the valve body is fixed to the outer peripheral surface of the valve body. 3. The valve body (9) according to claim 1 , wherein the packing (25) passes through the annular ridge (30) from the backflow preventing airtight surface (27) to the normal flow preventing airtight surface (28). When the packing (2) is moved, the packing (2) is stopped at that position at the shoulder (31) of the main body (2).
5. The welding safety device according to claim 1 , wherein 5) contacts an airtight surface (31) of an inner peripheral surface of the flow path of the main body (2) to prevent an abnormally high backflow. 4. A cylindrical main body having a flow path for combustion gas.
(2) and a valve element (9) incorporated in the flow path of the main body.
The airtight surface for backflow prevention (35) and the airtight surface for normal flow prevention (36) are provided with an annular raised portion (3 ) on the outer peripheral surface of the valve element (9).
Is formed on both sides of the 7), the packing in contact with both of these airtight surface (33) is fixed to the inner peripheral surface of the flow path of the body (2), reverse-blocking airtight surface of the valve body (9) (35) comes into contact with the packing (33) to prevent the backflow with the generation of the relatively low backflow pressure, and the bulge (37) of the valve element (9) with the generation of the abnormally high backflow due to an explosion or the like. Is an airtight surface (36) for preventing normal flow through the packing (33)
Is sent to the side that comes into contact with the packing (33), and contacts the packing (33) when a normal flow is generated, thereby preventing a normal flow. Valve body 5. A method according to claim 4 (9), when the normal flow blocking airtight surface of the valve body (36) has moved to the side in contact with the packing (33), the shoulder of the main body (2) It is stopped at that position by parts (39), according to claim 4 in which the gas-tight surface of the outer peripheral surface of the valve body (9) at the stop position (38) prevents an abnormally high flow back into contact with the packing (33) Safety device for welding. 6. The valve element (9) has a rod shape and the packing (16, 25, 33) has an airtight surface (2) for preventing normal flow.
0, 28, 36) to the airtight surface (19, 2) for preventing backflow.
The welding safety device according to any one of claims 1 to 5 , wherein the welding safety device is sent so as to relatively move toward the (7, 35) side.