JP3768588B2 - Manufacturing method of tip for arc welding - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a method for manufacturing a tip for arc welding that is used in an arc welding torch and has a through-hole for feeding power to a consumable electrode wire in an axial core portion.
[0002]
[Prior art]
In general, as shown in FIG. 3A, an arc welding tip is drilled with a wire insertion hole 103 having a small diameter by using a tip member 101 made of a chrome copper alloy round bar, (2) Cutting the taper portion 104 in the first half of the welding tip, (3) Applying the male screw 106 for attaching the welding tip, (4) Processing the taper portion 105 for wire guidance, and (5) Processing of a so-called spanner hanging portion 102 for attaching / detaching the welding tip was performed.
In this way, if the tip member 101 made of a round bar material is all machined to produce a welding tip, the manufacturing cost of the welding tip becomes high. In particular, although the electrode wire has a diameter of, for example, 0.8 to 1.8 mm, the tip length L is, for example, 40 to 45 mm, so that the drill is easily broken during drilling. I had to do it at low speed. That is, the manufacturing cost of the welding tip has been increased by taking time and effort for drilling.
[0003]
In order to cope with the above, a method for manufacturing a welding tip by so-called swaging has been proposed as described in Japanese Patent Publication No. 56-25353. That is, as shown in FIG. 3B, the hard wire 20 is inserted into the shaft core portion of the tip member 101 in which a hole 107 having a large-diameter inner diameter is formed in advance, and the tip member 101 is inserted into the dies 21 and 22. ...,..., By pressing the tip member 101 to the left by a desired amount while impact-pressing from the outside toward the center direction to form a wire insertion hole 103 in the front half of the tip member 101.
[0004]
[Problems to be solved by the invention]
By the way, when the welding tip is manufactured by the above swaging, the feeding length L ₂ of the welding tip manufactured by the swaging with respect to the length L of the welding tip is equal to the welding length manufactured by drilling. shorter than the feed length L ₁ of the use chip, the power feeding section L ₂ at the time of welding to wear prematurely, has a drawback that a short life of the welding tip. That is, there is a drawback that the welding tips must be frequently replaced during the welding operation.
[0005]
The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a method for manufacturing a welding tip that is easy to process and can increase the feeding length of an electrode wire.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the first aspect of the present invention is applied to a method for manufacturing an arc welding tip having a feed through hole for a consumable electrode wire in an axial core portion.
The feature is that a first step of cutting a through hole having a diameter larger than the through hole for feeding to a round bar cut to a desired length, and a cross-sectional shape in the radial direction of the round bar A second step of forging into a polygonal shape having at least one set of parallel planes; a third step of forming a tapered portion by forging on one end of the forged chip member; A fourth step comprising a cutting process for forming a feed through hole of a desired diameter with the formed hole as a lower hole and a terminal process for finishing both ends of the tip member; and the third and fourth steps. And a fifth step of forming a male screw on the other end side of the chip member.
[0007]
Furthermore, the second invention is characterized in that, in the first invention, the fifth step comprises a screwing process by lathe or forging and a screw process by rolling.
[0008]
According to a third aspect of the invention, in the first aspect of the invention, the fifth step includes a threading process by lathe or forging and a threading process by cutting.
[0009]
First, in the first step, cutting of a through-hole having a diameter larger than that of the power supply through-hole, that is, drilling is performed, so that the processing becomes simpler than the case of drilling a small-diameter power supply through-hole.
For example, when the diameter of the target power supply through hole is 0.8 mm, a drill of 2.0 to 2.2 mm can be used. That is, if the drill is 2.0 mm, the area ratio is about 6.2 times that of the 0.8 mm drill, so that processing of a large-diameter through hole can be performed very easily.
Of course, the material of the chip member is an expensive chrome copper alloy, but since it is an easily available general-purpose round bar, the material cost can be reduced.
[0010]
In the second step, the round bar provided with the large-diameter through-hole is forged into a polygonal shape in which the radial cross-sectional shape has at least one set of parallel planes. Thereafter, in the third step, A tapered taper portion is formed on one end side of the chip member by forging.
By the second and third steps, the tip member is formed in a desired shape in the radial direction, and the tip member is extended in the major axis direction to be formed in the desired shape.
[0011]
That is, since the tip member provided with the large-diameter through hole is stretched in the radial direction and the long axis direction by the second and third steps, the metal structure of the tip member is densified.
As described above, the forging densifies the tip member and improves the conductivity, tensile strength, and hardness of the tip member.
[0012]
On the other hand, when attention is paid to the shaft core portion of the chip member, the diameter of the through hole in the shaft core portion of the chip member is reduced to a substantially closed state by the second and third steps.
[0013]
Thereafter, the fourth step and the fifth step are appropriately performed before and after the third and fourth steps, but the features of the present invention are particularly remarkable in the fourth step. Appears in
That is, in the fourth step, a power supply through-hole having a desired diameter is formed by cutting the shaft core portion of the chip member.
[0014]
By the way, as shown in FIG. 4, a blade surface having a tip angle α of 118 degrees is generally formed at the tip of the drill, and a radial direction forming a so-called chisel angle θ of 110 to 135 degrees is formed at the tip of the blade surface. The chisel edge is formed, and at the time of drilling, the axial center portion of the hole is cut by the chisel edge, and a desired hole machining is performed.
[0015]
Of course, since the chisel edge is provided in the vicinity of the shaft center, the rotational speed is low, and the cutting force is smaller than that of the outer peripheral portion of the drill during drilling.
Moreover, from a macro perspective, during drilling, the rotation of the drill shaft is substantially close to zero, so the vicinity of the shaft is cut by a chisel edge portion slightly separated from the shaft in the radial direction.
[0016]
For this reason, when a small-diameter drill is performed on a chip member made of a solid bar material of chrome copper, the shaft core portion of the chip member corresponding to a chisel edge whose cutting force is substantially close to zero prevents drilling. Moreover, since the material is a hard chrome copper alloy, the drilling speed was slow and the drill was easy to break.
[0017]
By the way, in the present invention, in the fourth step, the state just before cutting the target small-diameter power supply through hole is the axial portion of the tip member by the second and third steps, that is, by forging. The large-diameter through-hole formed in is reduced in diameter and is almost closed.
In this state, drilling is performed to drill a power supply through-hole having a desired diameter in the shaft core portion of the tip member.
[0018]
At the time of this drilling process, the closed hole trace portion remaining on the shaft core portion of the tip member is equivalent to a state where the shaft core portion is perforated when viewed macroscopically. The state that hinders processing is eliminated.
Further, since the closed hole trace portion remaining in the shaft core portion of the tip member extends in the long axis direction, the hole trace portion serves as a guide in the long axis direction of the drill tip during drilling, This has led to the promotion of drilling work.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments.
In FIG. 1 and FIG. 2, first, as shown in FIG. 1A, as a first step, a solid round bar 101 made of a chrome copper alloy cut to a desired length is used as a target. Cutting of the through hole 107 having a diameter larger than that of the power supply through hole 103, that is, drilling is performed.
[0020]
Next, as shown in FIG. 1B and FIG. 2, as a second step, the radial cross-sectional shape of the tip member 101 is determined by the forging tools 31, 32,. Forged into a polygonal shape having at least one set of parallel planes.
In this case, the polygonal shape is formed in a quadrangular shape, a hexagonal shape, or an octagonal shape, but the most preferable shape is a hexagonal shape considering the forging effect described later and the state of use of the arc welding tip after manufacture. The next preferred shape is a square shape.
[0021]
Next, as shown in FIG. 1C, as a third step, a tapered tapered portion 104 is formed on one end side of the chip member 101 by forging.
By the second and third steps, the tip member 101 is formed in a desired shape in the radial direction, and the tip member 101 is extended in the long axis direction to be formed in the desired shape.
When attention is paid to the axial part of the tip member 101, the through hole 107 of the axial part of the tip member is reduced to a substantially closed state by the second and third steps. Is done.
[0022]
Next, the other end portion of the chip member 101 is subjected to, for example, screwing processing, which will be described later.
[0023]
After the third step, as shown in (E ₁ ) and (E ₂ ) of FIG. 1, as the fourth step, the shaft core of the tip member 101 whose diameter has been reduced to the substantially closed state by the forging. Cutting processing for forming a feed through hole 103 with a desired diameter in the portion, and end processing for finishing processing such as processing of both ends of the chip member 101 and taper processing 105 for wire guidance are performed.
[0024]
Thereafter, as shown in FIG. 1F, for example, a fifth step of forming the male screw 106 at the end of the chip member 101 is performed.
The fifth step of forming a male screw at the end of the chip member 101 is performed by (D) and (F) in FIG.
Thus, the arc welding tip is manufactured.
[0025]
According to the manufacturing method of the present invention,
(1) In the first step, the round bar is drilled with a through hole 107 having a diameter larger than that of the target power supply through hole 103. For example, the diameter of the target power supply through hole is 0. 0. In the case of 8 mm, a drill of 2.0 to 2.2 mm can be used.
That is, if the drill is 2.0 mm, the area ratio is about 6.2 times that of the 0.8 mm drill, so that drilling can be performed quickly without paying attention to breakage of the drill. In other words, the processing of the large-diameter through hole 107 can be performed very easily.
Of course, the material of the chip member is an expensive chrome copper alloy, but since it is an easily available general-purpose round bar, the material cost can be reduced.
[0026]
(2) Since the tip member provided with the large-diameter through hole is stretched in the radial direction and the major axis direction by the second and third steps, the metal structure of the tip member is densified. .
As described above, the forging densifies the tip member and improves the conductivity, tensile strength, and hardness of the tip member.
[0027]
(3) In the fourth step, the features of the present invention are particularly prominent.
In general, as shown in FIG. 4, a blade surface having a tip angle α of 118 degrees is formed at the tip of the drill 4, and a radial chisel edge forming a so-called chisel angle θ of 110 to 135 degrees is formed at the tip of the blade surface. 5 is formed, and at the time of drilling, the axial center portion of the hole is cut by the chisel edge 5 and desired hole processing is performed.
[0028]
Of course, since the chisel edge 5 is provided in the vicinity of the shaft center, the rotational speed is slow, and the cutting force is smaller than that of the outer peripheral portion of the drill during drilling.
Moreover, from a macro perspective, during drilling, the rotation of the drill shaft is substantially close to zero, so the vicinity of the shaft is cut by a chisel edge portion slightly separated from the shaft in the radial direction.
[0029]
For this reason, when a small-diameter drill is performed on a chip member made of a solid bar material of chrome copper, the shaft core portion of the chip member corresponding to a chisel edge whose cutting force is substantially close to zero prevents drilling. Moreover, since the material is a hard chrome copper alloy, the drilling speed was slow and the drill was easy to break.
[0030]
By the way, in the present invention, in the fourth step, the state just before the target small-diameter feed through hole 103 is cut is the axis of the tip member 101 by the second and third steps, that is, by forging. The large-diameter through-hole 107 provided in the core portion is reduced in diameter and is almost closed.
[0031]
In this state, a drilling process is performed in which a power supply through-hole 103 having a desired diameter is drilled in the shaft core part of the tip member 101. Since the shaft core portion is equivalent to a perforated state when viewed macroscopically, the state of the drill core portion in the shaft core portion of the chisel edge is eliminated.
Further, since the closed hole trace 108 remaining in the shaft core portion of the tip member extends in the long axis direction, the hole trace 108 serves as a guide in the long axis direction of the drill tip during drilling. , Leading to the promotion of drilling work.
[0032]
Incidentally, in the fourth step, when drilling the feed through hole 103 having a desired diameter in the closed hole trace portion 108 remaining in the shaft core portion of the tip member 101, for example, the time for drilling 0.8 mm is as follows. It was about 1/4 to 1/3 of the time when drilling directly into a solid bar of chrome copper alloy.
[0033]
Note that the fifth step of forming the male screw 106 at the end of the chip member 101 has been described as being performed by (D) and (F) of FIG. Thereafter, the threaded portion can be subjected to threading by cutting or rolling.
[0034]
In this case, if the unthreading process is performed by forging and the unthreading part is threaded by rolling, the material of the chip member can be used effectively, and the male thread can be formed quickly.
[0035]
Of course, if the under-screw processing is performed by a lathe, the forging machine is not necessary and the lathe operation is performed by hand, so that the processing can be easily performed. Of course, in this case, if the male thread processing is rolled, the thread formation time is shortened.
[0036]
Regardless of the above, male thread processing can also be performed at once by forging. In addition, the 5th process of forming a male screw in the one end part of a chip | tip member can be suitably given before and after the said 3rd and 4th process.
Needless to say, the end processing for finishing the ends of the chip member 101 and the taper processing 105 for guiding the wire in the fourth step in the above may be the final step of chip manufacturing.
[0037]
In short, in the first step, in combination with the fact that drilling of the through hole 107 having a diameter larger than that of the target through hole 103 for power supply can be performed extremely easily in the solid round bar, In the process 4, since the power supply through-hole 103 having a desired diameter can be drilled in the closed hole trace portion 108 remaining in the shaft core portion of the tip member 101 in a short time, the machining is simple and the drill is performed. The power supply part of the tip for arc welding formed by is formed longer than that manufactured by the conventional swaging process, and the tip member is densified by forging, and the conductivity, tensile strength and hardness of the tip member Therefore, the life as an arc welding tip is prolonged.
[0038]
【The invention's effect】
As is clear from the above description, the arc welding tip manufacturing method according to the first aspect of the present invention is an arc welding tip manufacturing method having a feedthrough hole for a consumable electrode wire in an axial portion. And
A first step of cutting a through-hole having a diameter larger than the through-hole for feeding to a round bar cut to a desired length; and at least one set of parallel planes in a radial cross-sectional shape of the round bar A second step of forging into a polygonal shape having a third shape, a third step of forming a tapered tapered portion on one end side of the forged tip member by forging, and a hole having a diameter reduced by the forging as a pilot hole A fourth step consisting of a cutting process for providing a power feed through hole of a desired diameter and a terminal process for finishing both ends of the chip member; and the other of the chip member before and after the third and fourth processes. Because it consists of a fifth step of forming a male screw on the end side,
In the first step, it is possible to extremely easily drill a through hole having a diameter larger than that of the target through hole for power supply in the round bar.
Furthermore, in the fourth step, when the through-hole for feeding with a desired diameter is drilled in the axial center portion of the chip member,
Since the closed hole trace portion remaining on the shaft core portion of the tip member is equivalent to a state in which the shaft core portion is perforated when viewed macroscopically, it hinders drilling at the shaft core portion of the chisel edge. The situation never happens,
In addition, the closed hole traces remaining in the shaft core portion extending in the long axis direction of the tip member serve as a guide in the long axis direction of the drill tip during drilling, thereby accelerating the drilling work. Therefore, it is possible to drill a power supply through-hole having a desired diameter in a closed hole trace portion remaining in the shaft core portion of the tip member in a short time.
[0040]
As described above, since each drilling can be easily performed in a short time, the machining is simple, and the power supply part of the arc welding tip formed by the drill is more than that produced by the conventional swaging process. Coupled with the formation of
Forging densifies the chip member and improves the conductivity, tensile strength and hardness of the chip member.
An arc welding tip manufacturing method having a long life as an arc welding tip can be realized.
[0041]
Further, in the manufacturing method of the tip for arc welding according to the second invention, in the first invention, the fifth step consists of under-screw processing by lathe or forging and screw processing by rolling, Screw formation time is shortened.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a manufacturing sequence of a welding tip according to the present invention. FIG. 2 is a sectional view taken along the line II-II in FIG. 1B. FIG. 3 is a front sectional view showing a conventional example. It is explanatory drawing of general drill processing.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Welding tip, 101 ... Tip member 102 ... Spanner hooking part, 103 ... Wire insertion hole 106 ... Male screw, 107 ... Through-hole 108 ... Hole trace part

Claims (3)

In a method for manufacturing an arc welding tip having a feed through hole for a consumable electrode wire in a shaft core, a round bar cut to a desired length is cut into a through hole having a diameter larger than that of the feed through hole. And forming the cross section of the round bar in the radial direction into a polygonal shape having at least one set of parallel planes and extending the round bar to a desired length in the major axis direction. A second step of forging the through-hole into a hole in a reduced diameter state that is substantially cooled, a third step of forming a tapered taper portion on one end side of the forged tip member by forging, and the forging A fourth process comprising a cutting process in which a through-hole for power supply having a desired diameter is formed with a hole reduced in diameter as a lower hole and a terminal process in which both ends of the tip member are finished, and the third and fourth processes A male screw is formed on the other end of the tip member. Fifth step and become more arc welding chip manufacturing method of that. The arc welding tip manufacturing method according to claim 1, wherein the fifth step includes a threading process by lathe or forging and a threading process by rolling. 2. The method for manufacturing a tip for arc welding according to claim 1, wherein the fifth step includes a threading process by lathe or forging and a threading process by cutting.

Images