JPS6359041B2 - - Google Patents

Description

Detailed Description of the Invention The present invention relates to a safety device for welding, and is particularly suitable for use as a safety device on the side of combustion gas such as acetylene. If the acetylene gas flows back to the acetylene gas side under this condition, the backflow flashback is prevented, thereby preventing an explosion of the combustion gas supply source, and the exposure of the mark notifies the occurrence of backflow.

Examples of the present invention will be described in detail below.

The welding safety device of the present invention includes a socket-side joint 1 and a plug-side joint 2 separably coupled to the socket-side joint 1, and gas flows from the socket-side joint to the plug-side joint.

As shown in FIG. 1, the socket side joint 1 includes a cylindrical socket portion 3, a cylindrical first valve chamber portion 5 connected to the socket portion with a screw 4, and a screw 6 connected to the valve chamber portion.
a second valve chamber part 7 connected to the second valve chamber part 7;
The socket body 10 is comprised of a joint part 9 connected to the socket body 10.

The socket part 3 has three holes 11 drilled at equal intervals around the peripheral wall of the socket part as a means for connecting the socket side joint 1 and the plug side joint 2, and a connecting ball 12 is installed in each hole. It has been inserted. Hole 11
is formed into a conical shape that becomes narrower toward the center of the socket portion 3, and prevents the connecting ball 12 from protruding inward from the hole 11. The connecting ball 12 connects the socket part 3 and the plug part 13 to each other by engaging with the annular connecting groove 14 of the plug part 13.

Further, a cylindrical detachable sleeve 15 is loosely fitted around the outer periphery of the socket portion 3 so as to be movable and rotatable from a forward position to a backward position or vice versa.
The removable sleeve 15 has a flanged retaining ring 16 connected to its outer circumferential end with a screw 17, a non-slip knurl 18 on the outer circumference of the retaining ring, and an annular protuberance 19 on its inner circumferential surface. Raised portion 19
When the detachable sleeve 15 is in the forward position, it moves away from the position where the connecting ball 12 is pushed in, allowing the connecting ball to move in the radial direction, and in this state, the plug part 13 and the socket part 3 are connected and removed. . Furthermore, when the removable sleeve 15 is in the retracted position, the raised portion 19 coincides with the position of the connecting ball 12 and pushes the connecting ball into the connecting groove 1 .
4, the plug part 13 and the socket part 3 are connected to each other.

The cylindrical intermediate member 20 is installed in an annular space between the socket portion 3 and the detachable sleeve 15, and has an outer flange 21 and an inner flange 22. By engaging the inner flange 22 with the retaining ring 23 of the socket part 3, the intermediate member 20 is coupled to the socket part 3 so as to be able to move forward and backward and rotate, and the outer flange 21 engages with the flange 24 of the retaining ring 16 and the raised part 19. The removable sleeve 15 is connected to the socket portion 3 so as to be movable forward, backward, and rotatable. A coiled compression spring 25 is attached to the inner flange 22
A coiled compression spring 27 is provided between the outer flange 21 and the detachable sleeve 1 to move the intermediate member 20 to the forward position.
5, and the removable sleeve is retracted with respect to the intermediate member 20.

The first valve chamber 5 has a first valve means built therein for blocking gas flow in the normal direction. As this valve means, a cylindrical valve seat 28 and a cylindrical rubber packing 29 are fixed in the valve chamber 5 by being held between the intermediate stage of the socket part 3, the end face of the valve chamber 5, and the intermediate stage. . Further, a valve body 30 that contacts the valve seat 28 is incorporated into the valve chamber 5 so as to move forward and backward, and the valve body 30 is supported by a coiled compression spring 3 in the valve chamber.
1 and is pressed against the valve seat 28. When the valve body 30 is pressed against the valve seat 28, the flow path is closed, and when it is away from the valve seat 28, the flow path is opened, and the gas flowing into the flow path from the end face of the joint portion 9 is Flows in from the outside through the through hole 32 in the peripheral wall of the valve body 30 and flows out from the end face of the socket portion 3.

Opening and closing of the valve body 30 is performed by the plug part 13. When the plug part is inserted into the socket part 3, the end face of the plug part 13 pushes the valve body 30 to open a flow path, and when the plug part is pulled out from the socket part. , the valve body 30 is pressed against the valve seat 28 by the spring 31 to close the flow path. In addition, 33 is a ring-shaped rubber packing that connects the valve body 3.
This is a member that is fixed at 0 and contacts the valve seat 28 to improve airtightness.

The second valve chamber 7 has a second valve means for preventing backflow and a means for preventing backfire incorporated therein.

The valve means includes a movable valve seat 34 and a movable check valve body 35.
Equipped with: The movable valve seat 34 has a cylindrical portion 36 , a flange-shaped seat 37 erected on the inner periphery, and an annular groove 38 formed on the outer periphery, and the cylindrical portion is fitted onto the inner periphery of the valve chamber 7 . It is movable in both directions with respect to the valve chamber in airtight contact via 39. The movable valve seat 34 is further constantly subjected to the elastic force of the compression spring 40, and is pressed to the forward position where it contacts the flange 41 in a normal state.

The check valve body 35 has a cylindrical portion 4 having a relatively large diameter.
2, a cylindrical portion 43 integrally connected to the cylindrical portion and having a smaller diameter, and a portion 44 extending from the cylindrical portion and closing one end thereof, and a rubber packing 45 is fixed to the portion 44. ing. This check valve body 35 is assembled into the cylindrical portion 36 of the valve seat 34, and the cylindrical portion 4
The outer circumferential surface of 2 is slidably in contact with the inner circumferential surface of the cylindrical portion 36, and the portion 44 is in the direction of the joint portion 9 (rightward in the drawing).
suitable for In a normal state, the check valve body 35 moves leftward to the flange 41 of the valve chamber 5 under fluid pressure.
The fluid flowing in the normal direction flows from the outside into the through hole 46 of the cylindrical part of the valve body, flows out in the direction of the socket part 3, and when it receives backflow pressure, it moves to the right. , the packing 45 is the seat part 37
to prevent backflow. A coiled compression spring 47 has a resilient force weaker than the fluid pressure in the normal direction.
is provided between the check valve body 35 and the flange 41, the check valve body 35 is moved by the spring 47 when backflow occurs.
It operates more sharply than without it.

The flashback prevention means is composed of a flashback prevention member 48 that is formed into a cylindrical shape by laminating a plurality of wire mesh plates. They are stacked so that they are sparse on the inside and denser on the outside, allowing gas to pass through but not flame. In addition to the wire mesh method, it is also possible to use materials with the same effectiveness, such as sintered metal made by sintering metal powder. The flashback prevention member 48 is incorporated in the valve chamber 7 so as to exist between the valve seat 34 and the joint 9, and one end thereof is connected to the intermediate step 50 of the valve chamber 7 via a packing 49. The other end is engaged with and held by a flange 53 of the joint portion 9 via a packing 51 and a guide plate 52, respectively. Backfire prevention member 48
An annular gap flow path is formed between the outer peripheral surface of the valve chamber 7 and the inner peripheral surface of the valve chamber 7, and gas flowing in the normal direction passes through the peripheral wall of the flashback prevention member 48 from the outside to the inside. When a backflow occurs, the valve body 35 moves to the right to prevent the backflow, but even if a backfire occurs and the flame flows back past the valve body 35, it will be blocked by the flashback prevention member 48.

The guide plate 52 guides the gas flowing into the joint portion 9 to the outer periphery of the flashback prevention member 48, and for this purpose, a cross-shaped groove 54 is formed on the outer surface of the guide plate 52. The gas is guided in the radial direction along the groove 54 and reaches the outer peripheral surface of the flashback prevention member 48 .
A rod-shaped portion 55 extends from the center of the guide plate 52, and a rubber packing 56 is fixed to the tip thereof. This further ensures prevention of backflow.

The valve chamber portion 7 further has an annular mark 57 on its outer periphery.
A cylindrical cover 58 is loosely fitted to cover or expose the mark. The mark 57 is preferably colored red, and the cover 58 is movable forward and backward and rotatable, and has an annular protuberance 59 on its inner peripheral surface. When the cover 58 is in the retracted position, the mark 57 is blocked by the cover, indicating that the gas flow is normal, and when the cover 58 is advanced, the mark 57 is exposed and backflow is recognized. In order to ensure its recognition, it is preferable to color the mark 57 red. A coiled compression spring 60 is provided in an annular space between the cover 58 and the valve chamber 7, and its both ends are connected to the raised portion 59 and the stepped portion 6.
1, giving the cover constant momentum to the left.

The steel balls 62 are stoppers that engage with the raised portions 59 of the cover 58 to hold the cover in the retracted position, and are inserted into three holes 63 drilled at equal intervals around the valve chamber portion 7. There is. The steel ball 62 is attached to the valve seat 3
4 is in the normal position, it protrudes from the hole 63 on the outer circumferential surface of the valve seat and engages with the raised portion 59 to hold the cover 58 in a position that shields the mark 57. When the valve body 35 is moved to the right by backflow pressure and the valve seat 34 is moved in the same direction, the annular groove 3 of the valve seat
8 reaches the position of the ball 62, the ridge 59 of the cover pushes the ball into the annular groove and advances to the left until it reaches the mark 57.
is exposed. When the cover 58 is moved back to the right from this state, the raised portion 59 is displaced from the position of the ball 62, the valve seat 34 is returned to its normal position by the spring 40, the ball 62 is pushed out, and the cover 58 is returned to its original position. to hold.

As shown in FIG. 2, the plug side joint 2 has a cylindrical plug part 13, a cylindrical hose joint part 64 integrally connected to the plug part, and a flange part 65 located between the two, There is an annular connecting groove 1 in the plug part.
4 is formed.

When the plug part 13 is inserted into the socket part 3 and pushed together with the intermediate member 20 against the springs 25 and 27, the connecting groove 14 reaches the connecting ball 12, and at the same time, the detachable sleeve 15 is moved back by the spring 27 and the connecting ball is moved. 12 is pushed into the connecting groove 14 and restrained, and both joints 1 and 2 are connected to each other as shown in FIG. 3.
The valve body 30 is opened by being pushed in by the plug part 13, and the gas flowing into the joint part 9 passes through the flashback prevention member 58 as described above, opens the check valve body 35, and passes through the socket part 3. It reaches the plug part 13 and the joint part 6
It flows out from 4. When backflow occurs, check valve body 3
5 is closed to prevent the backflow, and in the unlikely event that flame flows back past the check valve body 35, the flashback prevention member 48
At the same time, the movable valve seat 34 is retracted by the valve body 35, the cover 58 is advanced, and the mark 57 is exposed, so that the occurrence of backflow is recognized (FIG. 4).

When separating both joints 1 and 2, when the detachable sleeve 15 is advanced to the left in the state shown in FIG.
3 is pushed out from the socket part 3, and both joints 1 and 2
is released, and the valve body 30 is closed.

To use it again, move the cover 58 back to the right in the state shown in FIG.
7 is shielded by a cover, and at the same time the valve seat 34 is
0, it is returned to its original position together with the check valve 35.

The relationship between the cover 58 and the mark 57 is that of the cover 5.
8 may be fixed and the mark 57 may be movable to expose and shield the mark.

As described above, the welding safety device of the present invention is configured so that the mark is exposed and recognized by the relative movement of the cover 58 and the mark 57 when a backflow occurs, so that it can immediately respond to the backflow. As a result, the safety with respect to prevention of explosion is increased, and since the flashback prevention member 48 is incorporated, the above-mentioned safety is further increased.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a partially longitudinal front view of the socket-side joint, FIG. 2 is a partially vertical front view of the plug-side joint, and FIG. FIG. 4 is a partially longitudinal front view showing a state in which the flow is flowing in a normal direction, and FIG. 4 is a partially longitudinal front view showing a state in which both joints are connected and backflow flashback occurs. In the figure, 1 is the socket side joint, 2 is the plug side joint,
3 is a socket portion, 5 is a first valve chamber portion, 7 is a second valve chamber portion, 9 is a joint portion, 10 is a socket body, 12 is a connecting ball, 13 is a plug portion, 14 is a connecting groove, 15 is a detachable sleeve , 19 is a protrusion, 20 is a meson, 25
is a compression spring, 27 is a compression spring, 28 is a valve seat, 29
3 is a packing, 30 is a valve body, 31 is a compression spring, 3
3 is a packing, 34 is a movable valve seat, 35 is a movable check valve body, 37 is a seat, 38 is an annular groove, 40 is a compression spring, 47 is a compression spring, 48 is a flashback prevention member, 5
2 is a guide plate, 54 is a groove, 57 is a mark, 58 is a cover, 59 is a raised portion, 60 is a compression spring, 62 is a ball, 64 is a joint portion, and 65 is a flange portion.

Claims (1)

[Scope of Claims] 1. A first valve means capable of blocking the normal flow of combustion gas and a second valve means capable of blocking reverse flow in the flow path of the socket side joint that is separably connected to the plug side joint. At a position that can be recognized from the outside of the socket joint, there is a mark that indicates the occurrence of backflow and a cover that covers or exposes the mark by relative movement. Under normal conditions, the mark is covered by the cover, and backflow does not occur. a welding safety device that is moved relative to the cover in conjunction with actuation of the second valve means to expose the welding safety device upon occurrence of the 2. A first valve means capable of blocking normal flow of combustion gas, a second valve means capable of blocking reverse flow, and a passage of combustion gas are provided in the flow path of the socket side joint that is separably connected to the plug side joint. There is a backfire prevention means that allows the flame to pass through but prevents the passage of flame, and there is a mark on the outside of the socket side joint that makes it possible to recognize the occurrence of backflow, and a cover that blocks or exposes the mark by relative movement. A welding safety device in which the mark is shielded by a cover in a normal state and moves to an exposed position relative to the cover in conjunction with the operation of the second valve means in the event of backflow.