JPH03304Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention relates to a gas-shielded arc welding nozzle, and particularly to a gas-shielded arc welding nozzle with improved durability and welding workability. Related.

(Prior art and its problems) Conventionally used gas shielded arc welding nozzles are integrally formed of metal (copper) and are used by screwing onto the tip of a welding torch. It is something.

With this gas-shielded arc welding nozzle, the tip of the nozzle wears during use, making it easy for welding spatter to adhere to it. The disadvantage is that it requires a lot of effort to remove. 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 long periods of time, spatter adhesion to the nozzle as described above and the accompanying Preventing damage to equipment 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 ceramics, but as is well known, ceramics may have notches etc. Since this material is easily damaged, even if a gas-shielded arc welding nozzle with the same shape as a conventional one is made using this material, it would be extremely difficult to put it into practical use as is. .

Therefore, the present applicant filed an earlier application (Japanese Patent Application Laid-open No.
No. 92086), a support ring was screwed onto the tip of a welding torch, and a grip claw having an engaging protrusion was formed on the tip of the support ring, while a ceramic nozzle member was attached to the outer periphery of one end of the nozzle member. proposed a welding nozzle having a structure in which a groove is provided around the circumference and a nozzle member is fixed to a welding torch by fitting an engaging protrusion into the groove.

Although this welding nozzle can eliminate the above-mentioned drawbacks, the nozzle member requires high dimensional accuracy due to the use of the above-mentioned concave-convex fitting, so machining requires a large amount of time. As a result, the nozzle member becomes expensive.

This idea was made in view of the above, and its purpose is to make it difficult for spatter to adhere, to have good removability, to prevent short-circuit phenomena as described above, and to be manufactured at low cost. An object of the present invention is to provide a nozzle for gas shielded arc welding.

(Means for Solving the Problems) Therefore, the gas shielded arc welding nozzle of this invention, as shown in FIG.
It has a cylindrical nozzle member 3 attached to the tip side of the nozzle, and a retaining ring 4 arranged on the outer periphery of the support ring 2 and the nozzle member 3 to fix the nozzle member 3 to the support ring 2. There is. The nozzle member 3
is made of a non-conductive material such as ceramics, and has a protrusion 8 extending radially outward at one end thereof. Further, the retaining ring 4 has an engaging surface 9 on its inner circumference that engages with the projection 8. Further, the support ring 2 has a stepped portion 12 facing toward the proximal end on its outer periphery.
As shown in FIG. 2, the retaining ring 4 includes
In a state in which the engaging surface 9 is engaged with the protrusion 8, a pressing deformation portion that fits radially inward and engages with the stepped portion 12 at a position closer to the proximal end than the stepped portion 12. 13 is formed, and the retaining ring 4 is fixed to the supporting ring 2 by this deformed portion 13, and the nozzle member 3 is fixed to the supporting ring 2 by this retaining ring 4.

(Function) As described above, since the nozzle member 3 is used and the nozzle member 3 is made of a non-conductive material such as ceramics, it is difficult for spatter to adhere, and its removability is also good. This makes it possible to prevent short circuit phenomena between the welding material and the welded object.
It becomes possible to improve the durability of the gas shielded arc welding nozzle. Moreover, since welding can be performed with the nozzle member 3 in contact with the workpiece, it is possible to prevent shield failure due to the influence of wind, and the arc length can always be kept constant, making it possible to perform welding work. It becomes possible to improve efficiency.

Furthermore, since the above structure is adopted, the nozzle member 3 is not required to have high dimensional accuracy, and the nozzle member 3 and the entire welding nozzle can be provided at low cost. Also in this case,
The support ring 2 and the holding means 4 are fixed to each other with the engagement surface 9 of the holding means 4 engaged with the protrusion 8 of the nozzle member 3. The whole can be handled as a single part, which is convenient for nozzle replacement work, etc.

Further, as described above, by forming the press deformation portion 13 on the retaining ring 4, the retaining ring 4 is fixed to the support ring 2 and the nozzle member 3 is fixed, so that spot welding etc. Therefore, the above-mentioned fixing work can be easily performed, and the nozzle member 3 can be securely fixed.

(Embodiments) Next, specific embodiments of the gas-shielded arc welding nozzle of this invention will be described in detail with reference to the drawings.

In FIGS. 1 and 2, 1 is a welding torch, and a support ring 2 is screwed onto the tip end of the welding torch. A cylindrical nozzle member 3 is attached to the tip of the support ring 2, and a retaining ring 4 is fixed to the outer periphery of the support ring 2.

The support ring 2 is provided with a threaded portion 5 on the inner periphery of its proximal end, and this threaded portion 5 is screwed onto the tip of the welding torch 1. A support step 6 extending in the axial direction is formed at the tip of the support ring 2, and one end of the nozzle member 3 is fitted into the support step 6. In some cases, the support step 6 may be omitted, and the end surface of the nozzle member 3 may be held in contact with the tip surface of the support ring 2. Further, at the proximal side position of the support ring 2,
A groove 14 is provided around the circumference, but this groove 14
is for forming a step portion 12 facing toward the proximal end. Regarding the role of this stepped portion 12,
This will be explained later.

The nozzle member 3 is a cylindrical member, and near one end thereof, a plurality of through holes 7...7 are bored at equal intervals in the circumferential direction. The threaded portions of screws 8...8 are fitted into the through holes 7...7, and the heads of the screws 8...8 form protrusions extending radially from the nozzle member 3. Note that this protrusion can also be formed using a member other than the screw 8, and it is also possible to form the protrusion using a third member instead of the through hole 7.
A hole 18 with a bottom may be formed as shown in the figure.
Furthermore, instead of providing a plurality of protrusions as described above, a single protrusion may be used. In order to form the nozzle member 3, non-conductive materials such as ceramics are used.
Si ₃ N ₄ and ceramics mainly composed of Si 3 N 4 are materials with excellent high-temperature strength, wear resistance, and thermal shock resistance, and have been confirmed to be particularly preferable as materials for the nozzle member 3. In addition, the above
Tests were also conducted using a nozzle member 3 made of Al _{2 O 3 in} addition to Si ₃ N 4, etc., but the nozzle member 3 made of Si ₃ N ₄ was far superior in terms of both spatter adhesion amount and spatter removability. I confirmed that there is.

The retaining ring 4 has a tapered engagement surface 9 formed on the inner peripheral surface of its tip. This engagement surface 9 is formed so as to be inclined radially inward toward the distal end thereof, and is
This is the part that engages with the head of No.8.

Note that various materials can be used to form the support ring 2 and the retaining ring 4, but only materials that have good workability and that can effectively cool the nozzle member 3 from the welding torch main body side are used. Copper-based materials such as copper and brass are particularly suitable because they have good thermal conductivity.

The gas-shielded arc welding nozzle described above is assembled using the following procedure. First, one end of the nozzle member 3 is fitted into the support step 6 provided at the tip of the support ring 2 . And in this state, support ring 2
The retaining ring 4 is fitted onto the outer periphery of the holder. Then, the engaging surface 9 of the retaining ring 4 is engaged with the heads of the screws 8...8, and the retaining ring 4 is pushed toward the support ring 2, and the base end of the nozzle member 3 is attached to the support ring 2. When pressed against the stepped portion 6, opposing positions of the outer circumferential portion of the retaining ring 4 are pressed radially inward at the position of the groove 14 to form pressed deformed portions 13, 13. . This press deformation work is preferably carried out by spot welding, since the fixing of the retaining ring 4 to the support ring 2 involves the engagement of the press deformation part 13 with the step part 12 and the welding by the spot welding. This is because the above-mentioned nozzle member 3 can be reliably fixed. Note that the pressing deformation portion 13 can be formed by a method other than the spot welding method, and the number of deformation portions 13 to be formed is also arbitrary. and support ring 2 as above,
The nozzle member 3 and the retaining ring 4, which are entirely fixed, are attached to the welding torch 1 for use.

In the above-mentioned welding nozzle, since the nozzle member 3 made of ceramic is arranged at the tip, it is difficult for spatter to adhere, and even if spatter adheres, it is easy to peel off, and furthermore, it is easy to separate the chip from the welded object. It is possible to prevent a short circuit phenomenon between the welding nozzle and an object, and it is possible to improve the durability of the welding nozzle.
Moreover, since welding can be performed with the nozzle member in contact with the workpiece, shielding failure due to the influence of wind can be prevented, and the arc length can always be kept constant, increasing welding work efficiency. It becomes possible to improve.

In addition, because we adopted the mounting structure as described above,
Unlike conventional nozzle members 3, high dimensional accuracy is not required, machining becomes easy, and nozzle members 3, and by extension welding nozzles, can be provided at low cost. Furthermore, since the rings 2 and 4 and the nozzle member 3 are integrally fixed as described above, it is possible to handle the whole as a single component, which is convenient for work.

Further, as described above, by forming the press deformation portion 13 on the retaining ring 4, the retaining ring 4 is fixed to the support ring 2, and the nozzle member 3 is also fixed, so that it can be fixed by spot welding or the like. The above-mentioned fixing work can be easily performed, and the nozzle member 3 can be securely fixed.

4 to 7 show examples of changes in the formation structure of the step portion 12. FIG. 4 shows an example in which the stepped portion 12 is formed by providing a small diameter portion 15 on the base end side of the support ring 2, and FIG. FIG. 6 shows an example in which the stepped portion 12 is formed into a tapered shape, and FIG. An example is provided for each. Note that the formation structure of this stepped portion 12 is not limited to the above-mentioned structure, and any structure may be used as long as it can prevent the pressing deformation portion 13 from coming off. Furthermore, the step portion 12 is formed around the entire circumference of the support ring 2 as described above in order to facilitate processing of the support ring 2, and the step portion 12 is formed only at the position where the press deformation portion 13 is provided. may be formed.

FIG. 8 shows another embodiment of the arc welding nozzle. In this embodiment, an elastic body 10 such as silicone rubber or a plate spring is interposed between the base end of the nozzle member 3 and the step 6 of the support ring 2, and the elastic body 10 allows the nozzle to be This elastic body 1 supports the member 3 more reliably and reduces dimensional errors in each part.
It is made so that it can be absorbed by water. Note that the other parts are the same as those in the first embodiment, so the same parts are given the same reference numerals and the explanation thereof will be omitted.

(Effect of the invention) In the gas-shielded arc welding nozzle of this invention, a non-conductive material such as ceramics is used as the nozzle member as described above.
It is difficult for spatter to adhere and its peelability is good, and it is also possible to prevent short circuits between the chip and the workpiece, and as a result, the durability of gas shielded arc welding nozzles is improved. becomes possible. Furthermore, since a non-conductive material is used as mentioned above, it is possible to weld with the nozzle member in contact with the workpiece, which prevents shield failure due to the influence of wind and prevents arcing. Since the length can always be kept constant, welding efficiency can be improved. It has been confirmed that the average service life of the gas-shielded arc welding nozzle of this invention is several times longer than that of conventional nozzles.

In addition, because the structure is such that the engagement surface on the retaining ring side engages with the protrusion on the nozzle member side, and the support ring and retaining ring are fixed in this state, the nozzle member is required to have high dimensional accuracy as in the past. In fact, machining becomes easier, and therefore the nozzle member, and by extension the welding nozzle, can be provided at low cost. Furthermore, in this case, since the support ring, nozzle member, and retaining ring are fixed to each other, the whole can be handled as one component, which is convenient for nozzle replacement work.

In addition, as mentioned above, by forming a press deformation part on the retaining ring, the retaining ring is fixed to the support ring and the nozzle member is fixed, so the above fixing work by spot welding etc. is facilitated. This makes it possible to fix the nozzle member reliably.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway exploded perspective view of an embodiment of the gas-shielded arc welding nozzle of this invention, FIG. 2 is a central vertical sectional view thereof, and FIG. 3 is a vertical sectional view showing a modified example of the nozzle member. 4 to 7 are cross-sectional views showing modified examples of the formation structure of the step portion, respectively, and FIG. 8 is a vertical cross-sectional view of the main part showing a modified example of the nozzle. 1...Welding torch, 2...Support ring, 3...
Nozzle member, 4... Retaining ring, 7... Through hole, 8
...screw, 9...engaging surface, 12...step, 13...
...Press deformation part.

Claims (1)

[Scope of utility model registration request] A support ring attached to the tip of the welding torch, a cylindrical nozzle member attached to the tip side of the support ring, and arranged on the outer periphery of the support ring and the nozzle member to fix the nozzle member to the support ring. The nozzle member is made of a non-conductive material such as ceramics, and has a protrusion extending radially outward on one end thereof. The retaining ring has an engagement surface on its inner periphery that engages with the protrusion, the support ring has a proximally facing step on its outer periphery, and the retaining ring further has an engaging surface that engages with the protrusion. In a state in which the mating surface is engaged with the protrusion, a pressing deformation portion is formed that fits radially inward and engages with the step portion at a position on the proximal end side of the step portion, and this deformation portion A nozzle for gas shielded arc welding, characterized in that the retaining ring is fixed to the support ring by.