JP7323998B2 - welding torch - Google Patents

Description

The present invention relates to a welding torch used for consumable electrode gas shielded arc welding.

This type of welding torch is connected to the tip of a flexible conduit cable, and is injected from a nozzle while supplying power to the welding wire fed from a wire feeder and guided through the conduit cable. It is a member that plays a role of extending while being covered with shield gas, and its structure is disclosed in Patent Document 1, for example.

The wire is guided through a wire guide liner that extends to the central hole of a member called tip body in the welding torch. The wire receives power when passing through the center hole of the power feed tip connected to the tip side of the tip body. The shielding gas is led out from the internal space of the chip body into the nozzle internal space through the ventilation hole provided in the chip body and the orifice member provided on the outer periphery of the chip body, and surrounds the wire sent out from the power supply chip. In this way, it is jetted from the tip of the nozzle.

In the welding torch shown in the document, the central hole through which the wire guide liner is inserted is shared as a shielding gas passage, and the wire guide liner is a coil-shaped member. The leading end of the wire guide liner is simply abutted against the rear end of the feeding tip, and the rear end of the wire guide liner is simply abutted against the joint member for receiving the wire guide liner in the conduit cable. As a result, part of the shielding gas supplied to the center hole of the chip body leaks from the front end of the chip body through the wire insertion hole of the power supply chip, or leaks from the rear end of the chip body. There is a problem that the shielding function obtained by spraying the entire amount of the shielding gas from the tip of the nozzle so as to surround the wire cannot be achieved.

In addition, the welding torch disclosed in Patent Document 2 forms a separate shield gas supply path from the center hole of the tip body to eliminate waste due to gas leakage as described above. This leads to an increase in the size and complexity of the torch, which is disadvantageous in terms of cost.

JP 2017-51983 A Special Meeting No. 2018-65173

SUMMARY OF THE INVENTION The present invention has been conceived under the circumstances described above, and it is an object of the present invention to provide a welding torch which has a simple structure and is configured to eliminate leakage of shielding gas. Make it an issue.

In order to solve the above problems, the present invention employs the following technical means.

That is, the welding torch provided by the present invention includes a tip body, a power supply tip connected to the tip side thereof, a wire guide liner introduced into the center hole of the tip body for guiding the welding wire, and the tip body. and a nozzle surrounding the power feeding tip, wherein the welding torch performs welding by sending out the welding wire from the power feeding tip while injecting from the nozzle a shielding gas led out from the center hole of the tip body. The wire guide liner is characterized in that it has a pipe-shaped tip, and sealing means is provided between the outer circumference of the pipe-shaped tip and a member that receives the pipe-shaped tip.

In a preferred embodiment, the pipe-shaped distal end portion of the wire guide liner is received in a small diameter portion having an inner diameter corresponding to the outer diameter of the pipe-shaped distal end portion at the distal end portion of the center hole of the tip body. there is

In a preferred embodiment, the wire guide liner has a rear pipe-shaped end and sealing means are provided between the rear pipe-shaped end and a member receiving the rear pipe-shaped end.

In a preferred embodiment said sealing means is an O-ring.

In a preferred embodiment, said sealing means are screw means.

In a preferred embodiment, the shielding gas is supplied to the center hole of the chip body or to the cylindrical space surrounding the wire guide liner continuously with the center hole.

In the welding torch configured as described above, since the pipe-shaped tip of the wire guide liner and the member that receives this portion, for example, the tip of the center hole of the tip body, are sealed, the shielding gas is released from the tip of the wire guide liner. It is possible to prevent waste by leaking from the gap between the part and the center hole of the tip body.

In addition, since the welding torch having the above configuration follows the configuration in which the center hole of the tip body also serves as the supply path for the shielding gas, the configuration is simple and large compared to providing a separate shielding gas supply path. It does not lead to complication and cost increase.

Other features and advantages of the invention will become more apparent from the detailed description that follows with reference to the drawings.

1 is a longitudinal sectional view of a welding torch according to one embodiment of the present invention; FIG. FIG. 2 is an enlarged vertical cross-sectional view of the welding torch shown in FIG. 1 ; FIG. 2 is an enlarged vertical cross-sectional view of the welding torch shown in FIG. 1 on the device side; 3 is a cross-sectional view taken along line IV-IV of FIG. 2; FIG. 3 is a cross-sectional view taken along line V-V of FIG. 2; FIG. 3 is a cross-sectional view taken along line VI-VI of FIG. 2; FIG. 3 is a cross-sectional view taken along line VII-VII of FIG. 2; FIG. FIG. 4 is a cross-sectional view taken along line VIII-VIII of FIG. 3; FIG. 4 is a cross-sectional view taken along line IX-IX of FIG. 3; FIG. 6 is a vertical cross-sectional view of main parts of a welding torch according to another embodiment of the present invention; FIG. 6 is a vertical cross-sectional view of main parts of a welding torch according to another embodiment of the present invention;

Preferred embodiments of the present invention will be specifically described below with reference to the drawings.

As shown in FIGS. 1 to 3, a welding torch A1 is used for consumable electrode gas shielded arc welding and has a cooling mechanism. This welding torch A1 has a torch body 100, a tip body 200, a power supply tip 250, a wire guide liner 300, a nozzle 400, and an orifice member 500.

The torch body 100 is a cylindrical member, and its front end is connected to the rear end of the nozzle 400 via a connecting cylinder 150 . The connecting cylinder 150 connects the torch body 100 and the rear end portion of the nozzle 400 fitted on the insulating member 160 fitted on the tip body 200 by screw means, for example. The nozzle 400 takes in a power feed tip 250, which will be described later, and extends toward the tip of the torch.

The chip body 200 has a generally cylindrical shape and has a central hole 210 extending therethrough in the front-rear direction. The tip body 200 is made of a conductive metal, and a tip portion of which the diameter is reduced in a tapered shape is connected to a power feeding tip 250 . The power feed tip 250 is also made of a conductive metal, and has a wire delivery hole 251 formed therethrough along the torch central axis CL. The chip body 200 is electrically connected to a power supply cable (not shown).

A center hole 210 of the tip body 200 extends along the torch center axis CL and has a front end side small diameter portion 211 and a rear end side large diameter portion 212 . The inner diameter of the small-diameter portion 211 corresponds to the outer diameter of the pipe-shaped distal end portion of the wire guide liner 300, which will be described later, and the inner diameter of the large-diameter portion is larger than the outer diameter of the wire guide liner.

An annular orifice member 500 is fitted onto a portion of the chip body 200 facing the nozzle internal space 402 (FIGS. 2 and 5). An annular space 202 is formed between the inner peripheral surface 501 of the orifice member 500 and the outer peripheral surface 201 of the tip body 200 . The chip body 200 is formed with a vent hole 220 that allows the annular space 202 and the center hole 210 (large diameter portion 212) of the chip body 200 to communicate with each other. A plurality of vent holes 220 are formed at equal intervals in the circumferential direction of the chip body 200 (FIG. 6). The orifice member 500 is formed with an orifice hole 510 that communicates the annular space 202 with the inner nozzle space 402 . A plurality of orifice holes 510 are also formed at equal intervals in the circumferential direction of the orifice member 500 (FIG. 5). Several water passages 231, 232 are formed in the chip body 200, which will be further described later.

Inside the torch body 100, an inner cylinder 110 and an outer cylinder 120 are concentrically arranged adjacent to the rear end of the tip body 200 (FIGS. 2, 3 and 7). A cylindrical coolant introduction/discharge member 125 having an inner hole 126 surrounding the inner cylinder 110 is connected to the rear end of the outer cylinder 120 (FIGS. 3 and 8). A rear end portion 111 of the inner cylinder 110 extends further rearward than the rear ends of the outer cylinder 110 and the cooling water introduction/discharge member 125 and has a larger diameter. The inner diameter of the inner cylinder 110 is the same as the inner diameter of the rear end large diameter portion 212 of the center hole 210 of the tip body 200 . A space between the outer cylinder 120 and the inner cylinder 110 is used as cooling water passage spaces 131 and 132 . These water passage spaces 131 and 132 are divided into two regions in cross section, one being an outward passage water passage space 131 and the other a return passage water passage space 132 (FIGS. 3 and 7). These water passage spaces 131 and 132 communicate with a cooling water introduction port and a cooling water discharge port (not shown) of the cooling water introduction/discharge member 125 . An annular space 112 between the center hole 210 of the chip body 200 or the inner cylinder 110 and the wire guide liner 300, which will be described later, is a shield gas supply passage 112a. A shielding gas is supplied from a shielding gas supply port 115 provided at the rear end portion 111 of 110 .

The wire guide liner 300 is a cylindrical member that encloses and guides the welding wire W fed from a wire feeder (not shown), and within the scope of the welding torch A1, is in the form of a rigid pipe. have That is, this wire guide liner 300 is made of metal such as copper, stainless steel, or brass. In this embodiment, the wire guide liner 300 is formed by integrating the tip end joint 311 and the rear end joint 321 with the pipe member 301 having a uniform inner and outer diameter. Joint 310 and rear end joint 321 are collectively referred to as wire guide liner 300 . The front end side joint 311 and the rear end side joint 321 correspond to the pipe-shaped front end portion 310 and the pipe-shaped rear end portion 320 of the present invention, respectively.

The wire guide liner 300 has a pipe-shaped front end portion 310 (front-end joint 311) that is received and fitted in the front-end small diameter portion 211 of the center hole 210 of the tip body 200, and a pipe-shaped rear end portion 320 (rear end joint). 321) is received and fitted in the rear end portion 111 of the inner cylinder 110 of the torch body 100, so that it is arranged concentrically with the center hole 210 of the tip body 200 along the torch center axis CL. The pipe-shaped rear end portion 320 is pressed forward by a cap member 113 screwed onto the rear end of the rear end portion 111 of the inner cylinder 110 .

The tip body 200 has an outward passage water passage 231 communicating with the outward passage water passage space 131 formed in the torch body 100 , and a return passage water passage space 422 formed in the torch body 100 by folding back from the tip of the outward passage passage. A return water passage 241 communicating with is formed (FIGS. 2 and 4).

Therefore, as indicated by arrows in FIG. Water flows in order through the water space 132 to cool the welding torch A1, particularly the tip body 200, thereby contributing to the stabilization of welding quality.

As shown in FIGS. 2, 3, 4, and 9, an O-ring 611 held in an annular groove 612 provided in the small-diameter portion 211 of the center hole 210 of the tip body 200 is attached to the pipe-like tip of the wire guide liner 300. A sealing means 610 is provided by closely contacting the outer circumference of the portion 310 (the distal joint 311). Also, an O-ring 621 held in an annular groove 622 provided in the inner periphery of the rear end portion 111 of the inner cylinder 110 of the torch body 100 is attached to the paop-shaped rear end portion 320 (rear end side joint 321) of the wire guide liner 300. A sealing means 620 is provided by contacting the periphery.

Next, the operation of the welding torch A1 configured as described above according to the embodiment will be described.

Welding wire W sent through wire guide liner 300 is delivered from the tip of welding torch A1 through wire delivery hole 251 of power supply tip 250 . The shielding gas is supplied to the annular space 112 (shielding gas supply path 112a ) into the nozzle inner space 402 through the vent hole 220 or the orifice hole 510 of the orifice member 500, and is jetted so as to surround the welding wire W delivered from the tip of the nozzle 400 as described above. The shielding gas jetted in this way shields the welding portion and maintains the welding quality. At this time, since the front and rear ends of the annular space 112 are closed by the sealing means 610 and 620, the shielding gas does not wastefully leak from the front and rear ends of the annular space 112. It is jetted from the tip of the nozzle 400 .

Although the welding torch A1 according to the embodiment has a cooling function, its function is as described above.

Of course, the scope of the present invention is not limited to the above-described embodiments, and all modifications within the scope of matters described in each claim are included in the scope of the present invention.

For example, in the embodiment, the sealing means 610, 620 are formed by the O-rings 611, 621, but the specific means is not limited. Female threads 613 and 623 formed on the small diameter portion 211 of the hole 210 or the inner periphery of the rear end portion 111 of the inner cylinder 110 of the torch body 100, and male threads formed on the pipe-shaped front end portion 311 or the pipe-shaped rear end portion 321 of the wire guide liner. It may be constructed by screwing 614, 624 together.

Further, in the embodiment, the sealing means 610, 620 are provided on both the front end side and the rear end side of the wire guide liner 300, but they may be provided only on the front end side.

Furthermore, in the embodiment, the entire length of the wire guide liner 300 is formed into a pipe shape having rigidity, but only the limited portions of the leading end and the rear end are formed into a pipe shape suitable for providing sealing means, and the other portions are formed into a pipe shape. may be coiled.

In the embodiment, it is configured to have a water-cooling type cooling function provided with a cooling water flow path, but such a cooling water flow path is not particularly provided, and normal natural cooling is performed. Of course it's fine.

A1: Welding torch, W: Welding wire, 200: Tip body, 210: Center hole, 211: Small diameter portion, 250: Feeding tip, 300: Wire guide liner, 310: Pipe-shaped front end, 320: Pipe-shaped rear end , 400: nozzle, 610: sealing means, 620: sealing means, 611: O-ring, 621: O-ring

Claims (3)

A tip body containing a cooling water passage , a power supply tip connected to the tip side thereof, a wire guide liner introduced into a center hole of the tip body to guide a welding wire, the tip body and the power supply tip. and a welding torch for performing welding by feeding the welding wire from the power supply tip while injecting shielding gas led out from the center hole of the tip body from the nozzle,
The wire guide liner has an outer diameter corresponding to the small diameter portion at the tip of the center hole of the tip body, and is received in the small diameter portion of the center hole of the tip body and connected to the tip body. is held in an annular groove provided in the small-diameter portion of the center hole of the tip body between the outer periphery of the pipe-shaped tip portion and the small-diameter portion of the center hole of the tip body, and the pipe-shaped tip Welding torch, characterized in that it is provided with sealing means consisting of an O-ring which is tightly fitted around the outer circumference of the part . The wire guide liner has a pipe-shaped rear end, and sealing means comprising an O-ring is provided between the pipe-shaped rear end and a member for receiving the pipe-shaped rear end. 2. The welding torch according to 1. 3. The welding torch according to claim 1, wherein said shielding gas is supplied to said center hole of said tip body or to a cylindrical space surrounding said wire guide liner continuously with said center hole.

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