JPH0330470B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gas shielded arc welding nozzle, and more particularly to a gas shielded arc welding nozzle with improved durability and welding workability.

Conventionally used gas shielded arc welding nozzles are made of metal (copper) and are screwed onto the tip of the welding torch. When welding nozzles are used, the tip of the nozzle wears out during use, making it easy for welding spatter to adhere to the welding nozzle, making it difficult to stop welding work to remove the spatter, or to remove firmly adhered spatter. The disadvantage is that it requires a lot of effort. Moreover, the welding tip and the nozzle may be bridged by the adhered spatters, and the nozzle may come into contact with the workpiece during welding, resulting in a short circuit between the welding tip and the workpiece through the nozzle. , which caused damage to not only the nozzle but also the torch itself. This not only causes the disadvantage of economic loss due to damage to equipment, but also causes psychological pressure on workers who must always be aware of the above-mentioned short-circuit phenomenon during welding work. It is also a contributing factor.

In addition, even in automatic welding using robots, etc., whose application has been rapidly expanding in recent years, from the viewpoint of continuous work over a long period of time, spatter adhesion to the nozzle as described above and the accompanying Preventing equipment damage has become an important technical challenge.

In order to prevent the above-mentioned drawbacks, it may be possible to form the entire gas-shielded arc welding nozzle from a non-conductive material such as ceramic, but as is well known, ceramics may have notches etc. Since this material is easily damaged, even if a gas-shielded arc welding nozzle of the same shape as a conventional one is formed using this material, it would be extremely difficult to put it into practical use as is.

This invention was made in view of the above, and its purpose is to make it difficult for spatter to adhere, to have good removability, and to prevent short circuits as described above, as well as to prevent welding work and assembly work. An object of the present invention is to provide a gas-shielded arc welding nozzle with improved convenience.

The gas-shielded arc welding nozzle of the present invention, which achieves the above object, includes a support ring screwed onto the tip of a welding torch, a cylindrical nozzle member fitted onto the tip of the support ring, and an outer periphery of the support ring. The supporting ring has a threaded portion on the inner and outer periphery of the base thereof, and a plurality of elastically deformable gripping claws disposed in the circumferential direction on the distal end thereof. In addition, each of the gripping claws further has a radially inward engaging protrusion on the distal end thereof, and the outer periphery of each of the gripping claws is formed in a tapered shape that becomes larger in diameter toward the distal end. The nozzle member is made of ceramic, and has a concave groove on the outer periphery of at least one end thereof into which the engaging protrusion provided on the gripping claw can fit, and the outer tightening ring has the above-mentioned groove on the inner periphery of its base. It has a threaded part that can be screwed into the outer threaded part of the support ring, and also has a holding part on its tip side that comes into contact with the outer tapered part of the gripping claw part and presses it radially inward. It will be characterized by

As mentioned above, since the nozzle member is made of ceramic, it is difficult for spatter to adhere, and its peelability is also good, and the phenomenon of short circuit between the chip and the object to be welded is prevented. This makes it possible to significantly improve the durability of gas-shielded arc welding nozzles and welding workability.

Moreover, since the above-described structure is adopted, the nozzle member can be attached and detached by simply loosening the outer tightening ring, that is, by one touch, which is extremely convenient.

Furthermore, the elasticity of the gripping claws provides the following functions: absorbing thermal expansion and contraction of the nozzle member, preventing generation of excessive tightening force when tightening the outer tightening ring, and absorbing manufacturing errors of the nozzle member.

Next, specific embodiments of the gas shielded arc welding nozzle of the present invention will be described in detail with reference to the drawings.

In the figure, reference numeral 1 denotes a welding torch, and a support ring 2 is screwed onto the tip of the torch.A cylindrical nozzle member 3 is fitted onto the tip of the support ring 2. An outer tightening ring 4 is screwed onto the outer periphery of 2. Above support ring 2
As shown in FIGS. 2 and 3, its base 5
Threaded portions 6 and 7 are provided on the inner and outer circumferential portions of the welding torch 1, respectively, and the inner circumferential threaded portion 6 is screwed onto the tip of the welding torch 1. A plurality of (six in the figure) gripping claws 8 are provided on the distal end side of the support ring 2, and the gripping claws 8 in this case are It is formed by providing six slits 9 extending in parallel to the axial direction in a substantially cylindrical portion extending from 5 to the distal end side.
Furthermore, an engaging protrusion 10 having a semicircular cross section and protruding radially inward is provided on the inner peripheral portion of the distal end of each of the gripping claws 8 . Note that a tapered portion 11 is provided on the outer peripheral portion of the gripping claw portion 8 so that the diameter thereof gradually increases from the base side toward the distal end side.

As shown in FIG. 4, the nozzle member 3 is a cylindrical member, and grooves 12 having approximately the same cross-sectional shape as the engaging protrusion 10 are formed on the outer periphery near both ends of the nozzle member 3. It is set up. To form this nozzle member 3, non-conductive materials such as ceramics are used, and among them, Si ₃ N ₄ is
It is a material with excellent high-temperature strength, abrasion resistance, and thermal shock resistance, and has been confirmed to be particularly preferable as a material for the nozzle member 3. In addition, the above
In addition to Si ₃ N ₄ , a test was also conducted using a nozzle member 3 made of Al ₂ O ₃ , but the nozzle member 3 made of Si ₃ N ₄ was much better in terms of both the amount of spatter attached and the peelability of spatter. It was confirmed.

The outer tightening ring 4 is, as shown in FIG.
The base portion 13 has a threaded portion 14 on the inner periphery that can be screwed into the threaded portion 7 provided on the outer periphery of the support ring 2, and a cylindrical portion 15 on the distal end thereof. The inner diameter of this cylindrical portion 15 is selected to be smaller than the maximum diameter of the tapered portion 11 of the gripping claw portion 8 and larger than the minimum diameter, and serves as a holding portion 16.

Note that various materials can be used to form the support ring 2 and the outer tightening ring 4, but materials that have good workability and can impart sufficient elasticity to the gripping claw portion 8 are used. , in that the heat conduction is good enough to effectively cool the nozzle member 3 from the welding torch main body side,
Copper-based materials such as copper and brass are particularly suitable.

Next, a procedure for assembling the gas-shielded arc welding nozzle as described above will be explained. First, with the outer tightening ring 4 screwed onto the outer threaded portion 7 of the support ring 2, the inner threaded portion 6 of the support ring 2 is screwed onto the tip of the welding torch 1. Next, the nozzle member 3 is inserted between the gripping claws 8 and pushed in until the engaging protrusion 10 fits into the groove 12. Then, in a state in which the engagement protrusion 10 is fitted into the groove 12, the outer tightening ring 4 is rotated to move toward the tip side, and the holding portion 16 of the outer tightening ring 4
The assembly is completed by pressing the support ring 2 into contact with the tapered portion 11 of the support ring 2. In this way, since the holding part 16 of the outer tightening ring 4 is pressed into contact with the tapered part 11 of the support ring 2, the gripping claw part 8
It is possible to prevent the nozzle member 3 from expanding, and it is possible to effectively prevent the nozzle member 3 from falling off during welding work. In addition, when replacing the nozzle member 3, the outer tightening ring 4 is rotated in the opposite direction to the above and moved toward the base side, the pressure on the tapered part 11 by the holding part 16 is released, and the nozzle member 3 is replaced. All you have to do is pull it out from the gripping claw part 8. Note that the nozzle member 3 in the above embodiment is provided with two grooves 12, 12 near both ends. Of course, it is also possible to provide the groove 12 only at one end in order to enable reuse.

Although one embodiment of the gas shielded arc welding nozzle of the present invention has been described above, the gas shielded arc welding nozzle of the present invention is not limited to the above embodiment, and the cross-sectional shape of the engaging protrusion and the groove It is possible to make various changes and implementations within the scope of the objective of the present invention, such as changing the configuration and arrangement thereof.

The gas-shielded arc welding nozzle of the present invention is configured as described above, and therefore, spatters are difficult to adhere to and have good removability. This also makes it possible to prevent short-circuit phenomena between the chip and the workpiece, and as a result, it becomes possible to significantly improve the durability of gas-shielded arc welding nozzles and welding workability. . It has been confirmed that the average service life of the gas-shielded arc welding nozzle of the present invention is several times longer than that of conventional nozzles. Moreover, the nozzle member can be attached and detached by simply rotating the outer tightening ring, that is, by one touch, which is extremely convenient.

Furthermore, even if the nozzle member repeatedly expands and contracts due to temperature changes caused by heating during welding and subsequent cooling, this expansion and contraction will be absorbed by the elastic deformation of the gripping claws. , damage such as loosening of the gripping mechanism and cracking of the nozzle member can be prevented. Furthermore, when tightening the outer tightening ring in the nozzle assembly process, it is possible to prevent excessive tightening force from being applied to the nozzle member due to the elastic deformation of the gripping claws. Damage can be prevented. Even if there is a manufacturing error in the outer diameter dimension of the nozzle member, it can be absorbed by deformation of the gripping member, so there is an advantage that high accuracy is not required of the nozzle member.

[Brief explanation of drawings]

FIG. 1 is a central vertical cross-sectional view of one embodiment of the gas-shielded arc welding nozzle of the present invention, FIG. 2 is a central vertical cross-sectional view of the support ring used in the above, and FIG.
The figure is a side view of the support ring, FIG. 4 is a central vertical cross-sectional view of the nozzle member used in the above, and FIG. 5 is a central vertical cross-sectional view of the outer tightening ring used in the above. 1...Welding torch, 2...Support ring, 3...
Nozzle member, 4...Outer tightening ring, 6...Threaded portion, 7...Threaded portion, 8...Gripping claw portion, 10...Engaging protrusion, 12...Concave groove, 14...Threaded portion, 16 …
...Holding part.

Claims (1)

[Claims] 1. It has a support ring that is screwed onto the tip of the welding torch, a cylindrical nozzle member that is fitted on the tip side of the support ring, and an outer tightening ring that is screwed on the outer periphery of the support ring, The support ring has threaded portions on the inner and outer peripheries of its base, and a plurality of elastically deformable gripping claws disposed in the circumferential direction on its distal end, and the gripping claws further extend on its distal end. The nozzle member is made of ceramic, and the outer periphery of each of the gripping claws is tapered so that the diameter becomes larger toward the tip end. The outer tightening ring has a recessed groove into which the engaging protrusion provided on the gripping claw can fit, and the outer tightening ring has a threaded portion on the inner periphery of its base that can be screwed into the outer threaded portion of the support ring. have,
A gas-shielded arc welding nozzle characterized in that the tip side thereof has a holding portion that abuts the outer circumferential tapered portion of the gripping claw portion and presses it radially inward.