JPH0780047B2 - Variable shield box for welding - Google Patents

Description

Description: TECHNICAL FIELD The present invention mainly relates to a shield box for preventing oxidation during welding of active metal, and more particularly to a variable welding shield box suitable for welding curved joints. is there.

[Prior Art] A TIG welding method in which an arc is surrounded by an inert shield gas and tungsten is used as an electrode to prevent oxidation of a welded portion is widely used.

However, in the case of welding active metals such as titanium, tantalum, and zirconium, the surface oxidation of the welded portion is remarkable due to the high temperature immediately after welding.

Therefore, conventionally, as shown in FIGS. 7 and 8, the lower part of the elongated box a is opened, and the torch cup c of the TIG torch is inserted into the torch insertion hole b provided at one end of the box a. , The box a is fixed to the torch cup c with the shield box mounting screw d, and the shield gas pipe e disposed inside the box a
By ejecting a shield gas from the gas and passing the shield gas through the gas rectifying wire mesh f to uniformly cover the welding beads,
It has a back shield.

[Problems to be Solved by the Invention] However, since such a conventional shield box is fixed to the torch cup c, back welding can be performed without problems when welding a welding line on a flat surface. When welding the upper welding line, it is necessary to position the tungsten electrode g substantially perpendicular to the welding line, so that the lower surface of the shield box and the surface of the base material often do not become parallel, and a sound shield is ensured. I can't.

[Means for Solving Problems] An object of the present invention is to solve the above-mentioned problems and to obtain a sound back shield effect even under any circumstances when welding a curved joint of an active metal. In this case, the shield box bodies divided into front and rear are connected so that they can be bent, the top of the shield box body is attached to the upper part of the welding torch, and the slide box mounted on the top of the shield box body moves up and down without changing the welding electrode position. A variable shield box for welding, characterized in that shield gas pipes are respectively arranged in the front and rear shield box bodies, and a roller for positioning and moving is further provided under the front and rear shield box bodies. Is.

[Operation] The shield box body can be easily moved by the roller below the shield box body and can be bent back and forth because it is divided into the front and back, so that it can follow the welding line on the curved surface well and it is a back shield. Can be performed satisfactorily.

Further, even if the welding torch fluctuates in the vertical direction, the shield box can slide, so that the electrode insertion depth can be easily adjusted even within the groove.

Embodiments Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 and FIG. 2 show an embodiment of the present invention, in which the torch mounting seat 2 is provided at both sides of an annular torch mounting seat 2 into which the torch cup 1 can be inserted and fixed, at 180 ° opposite positions. Sliders 3 and 3 are fixed in the axial direction, and grooves 4 are provided on both side surfaces of the sliders 3 and 3, and sliders 5 and 5 having a U-shaped cross section are provided on the sliders 3 and 3, respectively. 4 are fitted to each other so that they can slide.

A shield box front part 6 having curved surfaces in the front-rear direction and the left-right direction and a shield box rear part 7 longer than the shield box front part 6 are connected to the sliders 5 and 5 at the top by brackets 8 and pins 9. is there. The connecting portions of the front part 6 and the rear part 7 of the shield box are provided with semi-circular notches so that they can be brought into close contact with the outer peripheral surface of the torch mounting seat 2 at the top, and both sides are brought into close contact with each other so that they pass each other. is there.

Shield gas pipes 10 and 11 are inserted into the front part 6 and the rear part 7 of each shield box from the top and arranged along inner walls 12 and 13, respectively, and the inner walls 12 and 13 of the shield gas pipes 10 and 11 are arranged. A large number of nozzles are provided on the side, and the rectifying wire nets 14 and 15 are provided at the front and rear portions of the shield box so as to be located below the shield gas pipes 10 and 11.
They are arranged in 6 and 7, respectively. Further, ball bearing type positioning rollers 16 and 17 capable of rotating 360 ° are attached to the lower end portions of the front and rear portions 6 and 7 of the shield boxes, respectively. In the figure, 18 indicates a tungsten electrode.

With the above configuration, the TIG torch is inserted and fixed to the torch mounting seat 2, and the shield box 20 is mounted on the outer peripheral portion of the torch mounting seat 2 so as to be able to move up and down.

A shield box 20 is placed on an active metal base material such as titanium so as to straddle a weld line 19 on a curved surface extending from a horizontal direction to a vertical direction as shown in FIG. 3, and a tongue-ten electrode 18 is provided as shown in FIG. Insert deeply into groove 21. At this time, since the positioning rollers 16 and 17 are grounded on the active metal base material, the torch mounting seat 2 is pushed by pushing the torch.
The sliders 3 and 3 are the sliders on the front and rear parts 6 and 7 of the shield box.
The tip of the tungsten electrode 18 is held at an appropriate distance from the groove 21 by sliding with 5, 5 and rising.

When the shield box 20 is moved along the welding line 19 in the curved surface while supplying power to the tungsten electrode 18 and the shield gas to the torch and further supplying the shield gas to the shield gas pipes 10 and 11, While the positioning rollers 16 and 17 of the front and rear parts of the box 6 and 7 are in contact with the surface of the base material, the front and rear parts of the shield box 6 and 7 are bent around the pin 9 pivotal part, and when the curved surface is the first, It deforms as shown by the chain double-dashed line in the figure. Therefore, even when the tungsten electrode 18 is welded in the groove 21 while repeatedly moving up and down, the shield boxes 12 and 13 always maintain a constant distance from the base metal, so that a healthy shield effect is always obtained and stabilized. Can perform arc welding.

The shield gas supplied to the shield gas pipes 10 and 11 is ejected toward the inner walls of the front and rear portions 6 and 7 of each shield box. Is centered around the arc point of the tungsten electrode 18 and is forced to wrap around the weld bead 22. Therefore, not only the arc point but also the welding bead 22 is completely shielded, so that the oxidation of the active metal at the time of welding can be completely prevented.

When welding of one layer is completed, as shown in FIG.
Even if is moved upward by one layer, the shield box 20 is moved downward by one layer due to its own weight, so that a constant shield effect is always obtained.

In the above, since the positioning rollers 16 and 17 employ the ball bearings, the positioning rollers 16 and 17 can smoothly respond to the moving direction of the torch.

The welding variable shield box of the present invention is not limited to the above-mentioned embodiment, and it goes without saying that various modifications can be made without departing from the scope of the present invention.

[Advantages of the Invention] As described above, according to the variable shield box for welding of the present invention, since the shield box bodies divided into the front and rear are pivotally attached so as to be openable and closable and movable by the rollers, the movable shield box moves along the curved surface. Even if it is done, the front and rear shield box bodies will always adhere well to the curved surface while keeping a constant interval, and the shield gas will be concentrated around the arc point and near the welding bead, so that the back shield can be completely performed. Also, since the shield box is mounted so that it can slide up and down, the insertion depth of the tungsten electrode can be easily changed and adjusted for each pass, and since the shield box is always in contact with the base metal surface by the roller, the tungsten electrode Left and right positioning can be easily done.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory view of an embodiment of the shield box of the present invention, FIG. 2 is a view taken along the line II-II of FIG. 1, and FIG.
The figure which shows the welding state of the curved welding line by the shield box shown in the figure, FIG. 4 is the IV-IV direction arrow view of FIG. 3, 5th figure
The figure shows a state in which welding beads are further laminated on the state shown in FIG. 4, FIG. 6 is an explanatory diagram showing an example of a conventional shield box, and FIG. 7 is a VII-VII direction arrow view of FIG. is there. 1 is a torch cup, 2 is a torch mounting seat, 3 and 5 are sliders, 6 is a shield box front part, 7 is a shield box rear part, 10 and 11 are shield gas pipes, 12 and 13 are inner walls, and 14 and 15 are for rectification Wire mesh, 16 and 17 are positioning rollers.

Claims (1)

[Claims] 1. A shield box body divided into front and rear portions is refractably connected, a top portion of the shield box body is attached to an upper portion of a welding torch, and a shield box body is attached by a slide attached to the top portion without changing a welding electrode position. A variable shield box for welding, characterized in that it is vertically movable, shield gas pipes are respectively arranged in the front and rear shield box bodies, and positioning and moving rollers are provided below the front and rear shield box bodies.