Wire Feeder

Abstract

To provide a relay body for welding, which is excellent in assemblability and maintainability.SOLUTION: A relay body 23 for welding, which is used to pass a welding current, is arranged between a welding power-supply unit and a welding torch, and composed of a metal conductor. The relay body for welding comprises a hollow gas passageway 231 which has a first opening 231a provided at one end and a second opening 231b provided at the other end and which is used to allow a flow of a gas, and a hollow cooling liquid passage 232 which has a third opening 232a provided at one end and a fourth opening 232b provided at the other end and which is used to allow a flow of cooling liquid.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a welding intermediate member and a wire feeder including the same. [Background technology]

[0002] Consumable electrode gas-shielded arc welding employs automatic welding using a welding robot or a traveling carriage, as well as semi-automatic welding operated by a worker. During welding operations such as these automatic welding operations, a wire feeder feeds welding wire toward a welding torch, and power and shielding gas are supplied to the welding torch. Welding power is supplied to the welding torch from a welding power source via a power cable or a conduit cable, for example. A power supply cable or a power supply conductor is arranged inside the wire feeder as a path for flowing welding current, and welding power is supplied to the welding torch via the power supply conductor or the like (see, for example, Patent Document 1). In the welding device described in Patent Document 1, the welding torch is a so-called water-cooled torch, and cooling water (coolant) is supplied to the welding torch. As shown in FIGS. 5 to 7 of Patent Document 1, a gas pipe and a water-cooled hose are also arranged inside the wire feeder.

[0003] As described in Patent Document 1 (see Figures 5 and 6 thereof), a power supply conductor 48 for supplying a welding current, a gas pipe 65 for supplying a shielding gas, and two water-cooling hoses 66 for supplying cooling water are separately arranged inside the wire feeder 4. In this configuration, the arrangement of the power supply conductor, gas pipes, and water-cooling hoses inside the wire feeder is complicated, and assembly and maintenance are difficult, leaving room for improvement. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2019-188428 Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been devised under these circumstances, and its main object is to provide a welding relay that is easy to assemble and maintain, and a wire feeder equipped with the same. [Means for solving the problem]

[0006] In order to solve the above problems, the present invention employs the following technical means.

[0007] A welding relay provided by a first aspect of the present invention is a relay that is arranged between a welding power supply and a welding torch, is made of a metal conductor, and is used to pass a welding current. The relay has at least one of a hollow gas passage having a first opening at one end and a second opening at the other end, for passing a gas, and a hollow coolant passage having a third opening at one end and a fourth opening at the other end, for passing a coolant.

[0008] A wire feeder provided by a second aspect of the present invention includes the welding relay according to the first aspect of the present invention and a wire feeder for feeding a welding wire.

[0009] In a preferred embodiment, the wire feeder is supported by the welding relay.

[0010] In a preferred embodiment, the welding relay includes both the gas passage and the coolant passage.

[0011] In a preferred embodiment, the first opening and the third opening are located on one side of the wire feeder in the feeding direction of the welding wire, and the second opening and the fourth opening are located on the other side of the wire feeder in the feeding direction.

[0012] In a preferred embodiment, the welding relay is made of aluminum. [Effects of the Invention]

[0013] The welding relay according to the present invention is disposed between a welding power supply and a welding torch. The welding relay is made of a metal conductor and is a component through which a welding current flows. Each welding relay has a hollow gas passage and a coolant passage. According to the present invention, the welding relay itself, which is the path for the welding current, has a hollow gas passage and a coolant passage. With this configuration, the welding relay can provide the paths for the welding current, shielding gas, and cooling water. This facilitates assembly and replacement of the welding relay in a device including the welding relay, resulting in excellent assembly and maintainability.

[0014] Other features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is an overall configuration diagram showing an example of a welding system including a wire feeder according to the present invention; [Figure 2] 1 is a schematic vertical cross-sectional view showing an example of a wire feeding device according to the present invention. [Figure 3] FIG. 3 is a cross-sectional view taken along line III-III in FIG. 2. [Figure 4] FIG. 4 is a cross-sectional view similar to FIG. 3, showing a modification of the wire feeding device shown in FIGS. 2 and 3. [Figure 5] FIG. 10 is an overall configuration diagram showing another example of a welding system including a wire feeder according to the present invention. [Figure 6] FIG. 10 is a schematic vertical cross-sectional view showing another example of a wire feeding device according to the present invention. [Figure 7] FIG. 7 is a cross-sectional view taken along line VII-VII in FIG. [Figure 8] FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG. 7. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

[0017] Fig. 1 is an overall configuration diagram showing an example of a welding system equipped with a wire feeder according to the present invention. The welding system A1 shown in Fig. 1 includes a welding power supply 1, a wire feeder 2, a welding torch 3, a torch cable 39, a power cable 71, a gas hose 72, and a water-cooling hose 73. The welding system A1 of this embodiment is used for so-called semi-automatic welding, in which a worker operates the welding torch 3, for example.

[0018] Welding power supply 1 supplies power for arc welding to welding torch 3. Welding power supply 1 converts three-phase AC power input from a power system (not shown) into DC power for driving the feed motor of wire feeder 2 and outputs the DC power to wire feeder 2 via power cable 71. One output terminal of welding power supply 1 is connected to welding torch 3 via power cable 71. Wire feeder 2 feeds welding wire to welding torch 3, causing the tip of the welding wire to protrude from the tip of welding torch 3. A contact tip disposed at the tip of welding torch 3 electrically connects power cable 71 and the welding wire. The other output terminal of welding power supply 1 is connected to a workpiece (neither of which is shown) via the power cable. Welding power supply 1 generates an arc between the tip of the welding wire protruding from the tip of welding torch 3 and the workpiece, and supplies power to the arc. Welding system A1 welds the workpiece using the heat of the arc.

[0019] In welding system A1, shielding gas is used during welding. The shielding gas is supplied from a gas cylinder (not shown) and delivered to the tip of welding torch 3 via wire feeder 2 through gas hose 72, which is installed to pass through welding power supply 1. In welding system A1 of this embodiment, welding torch 3 is a so-called water-cooled torch, and cooling water (coolant) is circulated through welding torch 3.

[0020] The wire feeder 2 feeds the welding wire to the welding torch 3. The welding wire passes through the inside of a torch cable 39 and a liner provided inside the welding torch 3, and is guided to the tip of the welding torch 3. In FIG. 1, the right side is the front of the welding wire feed direction X (hereinafter referred to as the "forward feed direction X1"), and the left side is the rear of the welding wire feed direction X (hereinafter referred to as the "rear feed direction X2"). In the description of the wire feeder 2 shown in FIGS. 1 to 3, the up-down direction is defined based on the position in which it is normally used. The feed direction X is a direction that is approximately along a horizontal plane.

[0021] Wire feeder 2 drives a feed motor and the like with power supplied from welding power supply 1 via power cable 71. This power is also supplied from wire feeder 2 to welding torch 3 via a power transmission line (not shown) provided inside torch cable 39. Wire feeder 2 communicates with welding power supply 1 via a signal line (not shown). Wire feeder 2 also communicates with welding torch 3 via a signal line (not shown) provided inside torch cable 39.

[0022] The wire feeder 2 includes a base 20, a device body 21, and a wire reel 22. The base 20 is, for example, flat, and supports the device body 21 and the wire reel 22. The wire reel 22 is a supply source of welding wire, and the welding wire is wound around the wire reel 22. As shown in FIGS. 2 and 3 , the device body 21 includes a welding relay 23, a wire feeder 24, and a cover 25.

[0023] Welding relay 23 is made of a metal conductor and is a member for passing a welding current. Welding relay 23 is disposed between welding power supply 1 and welding torch 3. In this embodiment, welding relay 23 is a block-shaped member. The shape of welding relay 23 is not particularly limited, and in this embodiment, welding relay 23 includes, for example, an upper wall portion 23A, a front wall portion 23B, and a rear wall portion 23C. Front wall portion 23B and rear wall portion 23C are located in the front feed direction X1 and the rear feed direction X2 of welding relay 23. Upper wall portion 23A is connected to the upper ends of both front wall portion 23B and rear wall portion 23C and extends in the feed direction X.

[0024] The welding relay 23 includes a gas passage 231 and a coolant passage 232. The gas passage 231 is a hollow passage for flowing gas, and in this embodiment, is a passage for flowing shielding gas. In the example shown in FIG. 2, the gas passage 231 is formed across the upper wall portion 23A and the front wall portion 23B. The gas passage 231 has a first opening 231a and a second opening 231b. The first opening 231a is provided at one end of the gas passage 231 and is located forward in the feeding direction X1 (one side in the feeding direction) with respect to the wire feeder 24. The second opening 231b is provided at the other end of the gas passage 231 and is located rearward in the feeding direction X2 (the other side in the feeding direction) with respect to the wire feeder 24.

[0025] The coolant passage 232 is a hollow passage for flowing a coolant, and in this embodiment, is a passage for flowing water (cooling water) as the coolant. In the example shown in FIG. 2, the coolant passage 232 is formed across the upper wall portion 23A and the front wall portion 23B. As shown in FIG. 3, two coolant passages 232 are formed in the welding relay 23. One coolant passage 232 is a water supply passage for sending coolant to the welding torch 3, and the other is a condensate passage for passing water returning from the welding torch 3. Note that in FIG. 2, the gas passage 231 and the coolant passage 232 are shown schematically, and the positional relationship between the gas passage 231 and the coolant passage 232 in the depth direction of the drawing differs from the actual position.

[0026] The coolant passage 232 has a third opening 232a and a fourth opening 232b. The third opening 232a is provided at one end of the coolant passage 232 and is located forward in the feeding direction X1 (on one side in the feeding direction) relative to the wire feeder 24. The fourth opening 232b is provided at the other end of the coolant passage 232 and is located rearward in the feeding direction X2 (on the other side in the feeding direction) relative to the wire feeder 24.

[0027] The welding relay 23 is provided with connectors 261, 262, 263, and 264. The connector 261 is fitted into a through-hole formed in the front wall portion 23B and has a gas flow path 261a. The gas flow path 261a communicates with the first opening 231a (gas passage 231). A through-hole extending in the feed direction X is formed in the center of the connector 261, and the welding wire W can pass through the through-hole. The connector 262 is threadedly connected to an end of the upper wall portion 23A on the rear side in the feed direction X2. The connector 262 communicates with the second opening 231b (gas passage 231). The gas hose 72 (see FIG. 1) is connected to the connector 262. The connector 263 is threadedly connected to a portion near the lower end of the front wall portion 23B. The connector 263 communicates with the third opening 232a (coolant passage 232). The connector 264 is screw-connected to the end of the upper wall portion 23A on the rear side in the supply direction X2. The connector 264 communicates with the fourth opening 232b (coolant passage 232). The water-cooling hose 73 is connected to the connector 264.

[0028] In the present embodiment, the welding relay 23 (rear wall portion 23C) is provided with a wire insertion hole 233. The wire insertion hole 233 is a through-hole formed in the rear wall portion 23C along the feeding direction X, and the welding wire W can pass through the wire insertion hole 233.

[0029] 2, the welding relay 23 includes an extension 23D extending rearward in the feeding direction X2 from the lower end of the rear wall 23C. A power cable 71 is connected to the extension 23D.

[0030] The welding relay 23 may be made of aluminum or an aluminum alloy, for example. The welding relay 23 may be formed by casting, for example. However, the welding relay 23 may be made of any material, such as copper, copper alloy, or other metal conductors.

[0031] Wire feeder 24 is a mechanical unit for feeding the welding wire. As shown in FIGS. 2 and 3 , wire feeder 24 includes, for example, a feed roller 241 and a pressure roller 242 that sandwich the welding wire, and a feed motor (not shown) that rotates and drives feed roller 241. Feed roller 241 is rotatably supported by, for example, a support plate 243, which is fixed to base 20. Pivoting arm 244 rotatably supports pressure roller 242. Pivoting arm 244 is rotatable between a closed position in which pressure roller 242 sandwiches the welding wire between itself and feed roller 241, and an open position in which pressure roller 242 is sufficiently spaced apart from feed roller 241.

[0032] As shown in FIGS. 2 and 3 , the cover 25 covers most of the welding relay 23. In the illustrated example, the cover 25 covers at least the upper surface and both side surfaces of the upper wall 23A. The cover 25 also covers the surface of the front wall 23B facing forward in the feed direction X1 (excluding the areas around the connectors 261 and 263) and the surface of the rear wall 23C facing backward in the feed direction X2 (excluding the areas around the connectors 262 and 264 and the wire insertion hole 233). The cover 25 is made of an electrically insulating material. Examples of materials that can be used to form the cover 25 include synthetic resins such as polyamide resin (glass fiber reinforced). However, the material that can be used to form the cover 25 is not limited to synthetic resins.

[0033] Welding torch 3 is operated by an operator to weld workpieces. Welding torch 3 includes torch body 31 and handle 32. Torch body 31 is a cylindrical metal member, and contains a liner through which a welding wire is inserted, a power cable, a gas pipe, and a water-cooling hose. Handle 32 is a part that an operator holds and is provided to hold the base end of torch body 31. Handle 32 is provided with torch switch 33. Torch switch 33 is located in a position where an operator holding handle 32 can easily press and operate it with their index finger. When torch switch 33 is turned on (depressed), an operation signal is input to welding power supply 1, causing welding power supply 1 to output welding power. When the on operation is released, welding power supply 1 stops outputting welding power. In other words, welding is performed only while torch switch 33 is pressed.

[0034] As shown in FIG. 1 , torch cable 39 is disposed between welding torch 3 and wire feeder 2. Connectors 35 and 36 are provided at the rear end of torch cable 39 in the feeding direction X2. Connector 35 is connected to connector 261 of wire feeder 2. Welding power, shielding gas, and welding wire are supplied from wire feeder 2 to torch cable 39 via connector 261 and connector 35. Connector 36 is connected to connector 263 of wire feeder 2. Cooling water flows between wire feeder 2 and torch cable 39 via connector 263 and connector 36.

[0035] Next, the operation of this embodiment will be described.

[0036] Wire feeder 2 of this embodiment includes welding relay 23 and wire feeder 24. Welding relay 23 is disposed between welding power supply 1 and welding torch 3. Welding relay 23 is made of a metal conductor and is a member through which a welding current flows. Welding relay 23 includes gas passage 231 and coolant passage 232. Gas passage 231 is a hollow passage for flowing shielding gas (gas) and has first opening 231a and second opening 231b at both ends. Coolant passage 232 is a hollow passage for flowing cooling water (coolant) and has third opening 232a and fourth opening 232b at both ends.

[0037] According to this configuration, in a path through which a welding current flows, for example, in wire feeder 2, welding relay 23 itself, which is the path through which the welding current flows, is provided with hollow gas passage 231 and coolant passage 232. According to this embodiment, unlike a configuration in which a power supply conductor, gas piping, and water-cooling hose are respectively arranged inside a wire feeder (for example, the configuration described in Patent Document 1), the paths for the welding current, shielding gas, and cooling water can be provided by welding relay 23. This facilitates assembly and replacement of welding relay 23 in a device including welding relay 23 (wire feeder 2 in this embodiment), resulting in excellent ease of assembly and maintenance.

[0038] Unlike the present embodiment, if a water-cooling hose is disposed inside the wire feeder, for example, the heat resistance temperature of the water-cooling hose may be exceeded under welding conditions such as high current and high duty cycle, which may impose restrictions on the welding conditions. In contrast, in the present embodiment, cooling water flows through a hollow passage (coolant passage 232) in welding relay 23 made of a metal conductor. Therefore, welding can be performed at high current and high duty cycle without being subject to restrictions on the welding conditions.

[0039] In the welding relay 23, one end (first opening 231a) of the gas passage 231 and one end (third opening 232a) of the coolant passage 232 are located forward in the feeding direction X1 (on one side in the feeding direction X) relative to the wire feeder 24. The other end (second opening 231b) of the gas passage 231 and the other end (fourth opening 232b) of the coolant passage 232 are located rearward in the feeding direction X2 (on the other side in the feeding direction X) relative to the wire feeder 24. As a result, the welding relay 23 is a structure that occupies a major part of the wire feeder 2. This configuration increases the strength of the entire wire feeder 2.

[0040] In this embodiment, the welding relay 23 is made of aluminum, which has a lower density than other metal conductors such as copper and iron. This configuration increases the overall strength of the wire feeder 2 and reduces the weight of the wire feeder 2.

[0041] 2 and 3, welding relay 23 has front wall 23B and rear wall 23C located in front X1 and rear X2 of the feeding direction, and wire feeding unit 24 (feed roller 241) and support plate 243 supporting it are disposed in the space between them in the feeding direction X. However, instead of this, for example, a structure shown in Fig. 4 may be employed. In Fig. 4 and subsequent figures, elements that are the same as or similar to those in the above embodiment are designated by the same reference numerals as those in the above embodiment, and description thereof will be omitted where appropriate.

[0042] The wire feeder 2′ shown in FIG. 4 is smaller than the wire feeder 2 shown in FIGS. 2 and 3 and includes a welding relay 23′, a rear cover 251, and a front cover 252. The front cover 252 is openable and closable. The welding relay 23′ shown in FIG. 4 supports the wire feeder 24 (feed roller 241) and plays a role similar to that of the support plate 243 shown in FIGS. 2 and 3. The welding relay 23′ is made of a metal conductor and is a member through which a welding current flows. The welding relay 23′ includes a gas passage 231 and two coolant passages 232. The gas passage 231 and the two coolant passages 232 each extend in the feed direction X (a direction perpendicular to the plane of FIG. 4). In the wire feeder 2′ shown in FIG. 4, the welding relay 23′, which serves as a path for the welding current, includes the hollow gas passage 231 and the hollow coolant passage 232. According to this configuration, unlike a configuration in which a power supply conductor, gas piping, and water-cooling hose are arranged inside the wire feeder (for example, the configuration described in Patent Document 1), the paths for flowing the welding current, shielding gas, and cooling water can be provided by welding relay 23'. This makes it easy to assemble and replace welding relay 23' in a device including welding relay 23' (wire feeder 2' in the configuration shown in FIG. 4), and provides excellent ease of assembly and maintenance.

[0043] In the examples shown in Figures 2 and 3, or Figure 4, the welding relay body 23 (welding relay body 23') is described as having both the gas passage 231 and the coolant passage 232, but the present invention is not limited to this, and the welding relay body 23 (welding relay body 23') may be configured to have either the gas passage 231 or the coolant passage 232.

[0044] FIG. 5 is a diagram showing the overall configuration of another example of a welding system equipped with a wire feeder according to the present invention.

[0045] The welding system A2 shown in FIG. 5 includes a welding power supply 1, a wire feeder 4, an intermediate cable 5, a wire feeder 6, a welding torch 3, a torch cable 39, a power cable 71, a gas hose 72, and a water cooling hose 73.

[0046] The wire feeder 4 feeds the welding wire to the welding torch 3. The welding wire is guided to the tip of the welding torch 3 through the intermediate cable 5, the wire feeder 6, the torch cable 39, and the inside of a liner provided inside the welding torch 3. The wire feeder 4 is a so-called push-side feeder. The wire feeder 4 drives the feed motor and other components with power supplied from the welding power supply 1 via a power cable 71. This power is also supplied from the wire feeder 4 to the wire feeder 6 via a power transmission line (not shown) provided inside the intermediate cable 5 and to the welding torch 3 via a power transmission line (not shown) provided inside the torch cable 39. The wire feeder 4 communicates with the welding power supply 1 via a signal line (not shown). The wire feeder 4 also communicates with the wire feeder 6 via a signal line (not shown) provided inside the intermediate cable 5, and with the welding torch 3 via a signal line (not shown) provided inside the torch cable 39.

[0047] The intermediate cable 5 is a cable for connecting the wire feeder 4 and the wire feeder 6. The intermediate cable 5 has a cable main body 51 and connectors 52 and 53. In this embodiment, a power cable, a gas hose, a liner, a power transmission line, and a signal line (none of which are shown) are arranged inside the cable main body 51. In this embodiment, a water-cooling hose (not shown) for flowing cooling water is also arranged inside the cable main body 51.

[0048] Connector 52 is provided at one end of cable main body 51. Connector 53 is provided at the other end of cable main body 51. Connector 522 is connected to wire feeder 4 via adapter 8. Through connector 52, the power cable, gas hose, water cooling hose, liner, power transmission line, and signal line inside wire feeder 4 are connected to the power cable, gas hose, water cooling hose, liner, power transmission line, and signal line inside cable main body 51, respectively. Note that although the middle portion of cable main body 51 is omitted in FIG. 5, the total length of intermediate cable 5 is, for example, approximately 10 m to 30 m.

[0049] Wire feeder 6 feeds welding wire to welding torch 3 and is a so-called pull-side feeder. Wire feeder 6 as a pull-side feeder corresponds to the "wire feeder" of the present invention. Wire feeder 6 shown in FIGS. 6 to 8 includes a welding relay 61, a wire feeder 62, and a case 63.

[0050] The welding relay 61 is made of a metal conductor and is a member for passing a welding current. The welding relay 61 is disposed between the welding power supply 1 and the welding torch 3. In this embodiment, the welding relay 61 is a block-shaped member. The shape of the welding relay 61 is not particularly limited. In this embodiment, the welding relay 61 includes, for example, a middle portion 61A, a side wall portion 61B, a front portion 61C, a rear portion 61D, and a lower portion 61E. The front portion 61C and the rear portion 61D are located at the front and rear ends of the welding relay 61 in the feed direction X1 and X2, respectively. The side wall portion 61B is connected to the ends (right side portions in FIG. 7 ) of the front and rear portions 61C and 61D in the width direction (directions perpendicular to both the feed direction X and the up-down direction) and extends along the feed direction X. The middle portion 61A is connected to the rear portion 61D and is located forward in the feeding direction X1 relative to the rear portion 61D. The lower portion 61E is located rearward and below the front portion 61C in the feeding direction X2.

[0051] The welding relay 61 includes a gas passage 611 and a coolant passage 612. The gas passage 611 is a hollow passage for flowing gas, and in this embodiment, it is a passage for flowing shielding gas. In the example shown in FIGS. 6 and 7, the gas passage 611 is formed across the side wall portion 61B, the front portion 61C, and the rear portion 61D. The gas passage 611 has a first opening 611a and a second opening 611b. The first opening 611a is provided at one end of the gas passage 611 and is located forward in the feeding direction X1 (one side in the feeding direction) with respect to the wire feeding portion 62. The second opening 611b is provided at the other end of the gas passage 611 and is located rearward in the feeding direction X2 (the other side in the feeding direction) with respect to the wire feeding portion 62.

[0052] The coolant passage 612 is a hollow passage for flowing a coolant, and in this embodiment, is a passage for flowing water (cooling water) as the coolant. In the example shown in FIGS. 6 and 7, the coolant passage 612 is formed across the side wall portion 61B, the rear portion 61D, and the lower portion 61E. As shown in FIG. 7, two coolant passages 612 are formed in the welding relay 61. One coolant passage 612 is a water supply passage for sending coolant to the welding torch 3, and the other is a condensate passage for passing water returning from the welding torch 3. Note that in FIG. 6, the gas passage 611 and the coolant passage 612 are shown schematically, and the positional relationship between the gas passage 611 and the coolant passage 612 in the depth direction of the drawing differs from the actual position.

[0053] The coolant passage 612 has a third opening 612a and a fourth opening 612b. The third opening 612a is provided at one end of the coolant passage 612 and is located forward in the feeding direction X1 (on one side in the feeding direction) relative to the wire feeder 62. The fourth opening 612b is provided at the other end of the coolant passage 612 and is located rearward in the feeding direction X2 (on the other side in the feeding direction) relative to the wire feeder 62.

[0054] The welding relay 61 is provided with connectors 641, 642, and 643. The connector 641 is provided in the front portion 61C. The connector 641 communicates with the first opening 611a (gas passage 611). The connector 641 is connected to the connector 35. The connector 642 is provided in the rear portion 61D. The connector 642 communicates with the second opening 611b (gas passage 611) and the fourth opening 612b (coolant passage 612). The connector 642 is connected to the connector 53. The connector 643 is provided in the lower portion 61E. The connector 643 communicates with the third opening 612a (coolant passage 612). The connector 643 is connected to the connector 36.

[0055] In this embodiment, the welding relay 61 (the front portion 61C, the intermediate portion 61A, and the rear portion 61D) is provided with wire insertion holes 613, 614. The wire insertion hole 613 is a through hole formed in the front portion 61C along the feeding direction X, and the welding wire W can pass through the wire insertion hole 613. The wire insertion hole 614 is a through hole formed in the intermediate portion 61A and the rear portion 61D along the feeding direction X, and the welding wire W can pass through the wire insertion hole 614.

[0056] The welding relay 61 may be made of aluminum or an aluminum alloy, for example. The welding relay 61 may be formed by casting, for example. However, the welding relay 61 may be made of any material, such as copper, copper alloy, or other metal conductors.

[0057] Wire feeder 62 is a mechanical part for feeding the welding wire. As shown in Figures 7 and 8, wire feeder 62 includes, for example, feed roller 621 and pressure roller 622 that sandwich the welding wire, feed motor 623 that drives feed roller 241 to rotate, and feeder case 624 that houses these components. Feeder case 624 is supported by lower portion 61E. Thus, wire feeder 62 is supported by welding relay 61.

[0058] As shown in Figs. 6 to 8, the case 63 covers most of the welding relay 61. In the illustrated example, the case 63 is formed by combining a pair of vertically separated pieces. The case 63 is made of an electrically insulating material. Examples of materials that can be used to form the case 63 include synthetic resins such as polyamide resin (containing glass fiber). However, the material that can be used to form the case 63 is not limited to synthetic resins.

[0059] Next, the operation of this embodiment will be described.

[0060] Wire feeder 6 of this embodiment includes welding relay 61 and wire feeder 62. Welding relay 61 is disposed between welding power supply 1 and welding torch 3. Welding relay 61 is made of a metal conductor and is a member through which a welding current flows. Welding relay 61 includes gas passage 611 and coolant passage 612. Gas passage 611 is a hollow passage for flowing shielding gas (gas) and has first opening 611a and second opening 611b at both ends. Coolant passage 612 is a hollow passage for flowing cooling water (coolant) and has third opening 612a and fourth opening 612b at both ends.

[0061] According to this configuration, in a path through which a welding current flows, for example, in wire feeder 6, welding relay 61 itself, which is the path through which the welding current flows, is provided with hollow gas passage 611 and coolant passage 612. According to this embodiment, unlike a configuration in which a power supply conductor, gas piping, and water-cooling hose are each arranged inside the wire feeder (for example, the configuration described in Patent Document 1), the paths for the welding current, shielding gas, and cooling water can be provided by welding relay 61. As a result, in a device including welding relay 61 (wire feeder 6 in this embodiment), welding relay 61 can be easily assembled and replaced, resulting in excellent ease of assembly and maintenance.

[0062] Unlike the present embodiment, if a water-cooling hose is disposed inside the wire feeder, for example, the heat resistance temperature of the water-cooling hose may be exceeded under welding conditions such as high current and high duty cycle, which may impose restrictions on the welding conditions. In contrast, in the present embodiment, cooling water flows through a hollow passage (coolant passage 612) in the welding relay 61 made of a metal conductor. Therefore, welding can be performed at high current and high duty cycle without being subject to restrictions on the welding conditions.

[0063] In the welding relay 61, one end (first opening 611a) of the gas passage 611 and one end (third opening 612a) of the coolant passage 612 are located forward in the feeding direction X1 (on one side in the feeding direction X) relative to the wire feeder 62. The other end (second opening 611b) of the gas passage 611 and the other end (fourth opening 612b) of the coolant passage 612 are located rearward in the feeding direction X2 (on the other side in the feeding direction X) relative to the wire feeder 62. As a result, the welding relay 61 is a structure that occupies a major part of the wire feeder 6. This configuration increases the strength of the entire wire feeder 6.

[0064] In the wire feeder 6 of this embodiment, the wire feeder 62 is supported by the welding relay 61. With this configuration, the strength of the welding relay 61 and the wire feeder 62 supported thereby is appropriately increased.

[0065] In this embodiment, the welding relay 61 is made of aluminum, which has a lower density than other metal conductors such as copper and iron. This configuration increases the overall strength of the wire feeder 6 and reduces the weight of the wire feeder 6.

[0066] In the examples shown in Figures 6 and 7 above, the welding relay body 61 is described as having both the gas passage 611 and the coolant passage 612, but the present invention is not limited to this, and the welding relay body 61 may be configured to have either the gas passage 611 or the coolant passage 612.

[0067] While the present invention has been described above in terms of an embodiment, the scope of the present invention is not limited to the above embodiment, and all modifications within the scope of the claims are encompassed within the scope of the present invention. In the above embodiment, the welding relay is used as a component of a wire feeder, but the present invention is not limited thereto. [Explanation of symbols]

[0068] 1: welding power supply, 2, 2': wire feeder, 23, 23': welding relay, 231: gas passage, 231a: first opening, 231b: second opening, 232: coolant passage, 232a: third opening, 232b: fourth opening, 24: wire feeder, 3: welding torch, 6: wire feeder, 61: welding relay, 611: gas passage, 611a: first opening, 611b: second opening, 612: coolant passage, 612a: third opening, 612b: fourth opening, 62: wire feeder, X: feed direction, X1: forward feed direction (one side of feed direction), X2: rearward feed direction (other side of feed direction), W: welding wire

Claims

1. a welding relay that is disposed between the welding power supply and the welding torch and is made of a metal conductor and that allows a welding current to flow; a wire feeding unit for feeding a welding wire, the welding relay includes a hollow gas passage having a first opening at one end and a second opening at the other end, for allowing a gas to flow, and a hollow coolant passage having a third opening at one end and a fourth opening at the other end, for allowing a coolant to flow, The welding relay body has a wire insertion hole through which the welding wire can be inserted, on one side of the wire feeding section in a feeding direction of the welding wire and on the other side of the feeding direction.

2. The wire feeder according to claim 1 , wherein the wire feeder is supported on the welding relay.

3. the first opening and the third opening are located on one side of the wire feeder in the feeding direction, The wire feeder according to claim 1 or 2, wherein the second opening and the fourth opening are located on the other side of the wire feeder in the feeding direction.

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