JPH09327770A - Welding equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the durability of a locking tube by forming a control surface to realize the appropriate advancing speed of a part at an end part of an introduction passage. SOLUTION: An advancing/retracting feed rod 2 is installed in a guide cylinder 1. A locking tube 5 of a parts 16 having the function of a movable electrode is joined to a tip of the guide cylinder 1. An introduction passage 25 of the parts 16 is installed in the direction to form an acute angle from the guide cylinder 1. A control surface 27 is formed at an end part of the introduction passage 25, and the advancing speed of the parts 16 becomes appropriate. A means 28 to transfer the parts 16 into the guide cylinder 1, i.e., an air ejection hole is installed in the vicinity of the end part of the introduction passage 25. A tip part of the feed rod 2 is a release part of gutter shape, which is opposite to an opening part of the introduction passage 25, and the parts 16 is held to the tip part of the feed rod 2 by a holding means. The locking tube can be advanced at an appropriate speed with which the locking tube is not damaged and worn.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has an advancing / retreating type feed rod installed in a guide tube, and a locking tube for a part having a function of a movable electrode is joined to the tip of the guide tube, and an introducing passage for the part Belongs to the technical field of a welding apparatus of the type in which it is installed at an acute angle with the guide tube and opens in the guide tube.

[0002]

2. Description of the Related Art FIG. 1 shows an embodiment of the present invention. The prior art will be described with reference to this drawing.
The apparatus shown in the figure is a stud welder or a projection welder.
Is inserted in a slidable manner, and although not shown in the figure, a supply rod 2 is connected via bolts 4 to a Biston rod 3 of an air cylinder connected to a guide cylinder 1. A locking tube 5 as a component is connected to the tip of the guide cylinder 1.
This is made of special steel, and the end of the locking tube 5 is inserted into the guide tube 1, and the cap nut 7 is fastened to the screw part 6 to integrate the guide tube 1 and the locking tube 5. Has been done.
The locking tube 5 is provided with a plurality of slits 8 in the axial direction, and a locking projection 9 is provided inside the end of the locking tube 5. The locking tube 5 functions as a movable electrode that causes a welding current to flow through the parts when the entire guide cylinder 1 has advanced.

Introducing hole 1 shown by a chain double-dashed line in guide tube 1
0 is cleared, which is the prior art structure. A supply hose 11 is connected to the introduction hole 10. Guide tube 1
The bracket 12 is welded to the bracket 12, and the piston rod 14 of the air cylinder 13 is joined to the bracket 12.
The air cylinder 13 is fixed to the stationary member 15, and the welding machine as a whole is guided by the output of the air cylinder 13.
It is designed to move back and forth in the axial direction. The component handled here is an iron bolt 16, which has a shaft portion 17 and a flange 18, and the flange 18 is formed with a raised portion 19 serving as a welded portion.

Further, as another conventional technique, as shown in FIG. 6 and FIG. 7 (these are also a part of the embodiments of the present invention, which are also used in the description of the conventional technique), a locking projection. However, instead of not projecting inward, the locking tube 5 is tapered, and the flange 18 of the bolt is temporarily locked on the inner surface of the locking tube 5.

[0005]

In the above-mentioned device, the bolt 16 enters the guide tube 1 through the introduction hole 10 and descends as it is, so that the flange 18 hits the locking projection 9 and is stopped. Due to the impact at this time, the locking projection 9 is gradually worn away, and in an extreme case, the locking projection 9 is damaged and the locking function is deteriorated, which is a durability problem. In general, since parts such as bolts are conveyed at high speed by air injection in the supply hose, the impact on the locking projections 9 becomes extremely high, and the above-mentioned problems such as wear become more important. Similarly, in the case of FIG. 6 as well, when the flange 18 is locked to the inner surface of the locking tube 5 at a high speed, only the inner surface of the locking tube 5 in this portion is worn, and thus the normal temporary locking is achieved. However, there is a problem that the flange 18 cannot smoothly slide in the locking tube 5.

[0006]

[Means for Solving the Problems and Their Functions] The present invention has been provided to solve the problems described above.
According to a first aspect of the present invention, an advancing / retreating type supply rod is installed in the guide cylinder, a locking tube of a component having a function of a movable electrode is joined to the tip of the guide cylinder, and the introduction passage of the component forms an acute angle with the guide cylinder. In the case where the guide passage is installed in an inclined direction and opened in the guide tube, a control surface for optimizing the approach speed of parts is formed at the end of the introduction passage. The part that has moved is temporarily stopped on the control surface, or is rapidly decelerated, so that the impact on the locking projection 9 of the locking tube 5 and the inner surface of the tapered portion of the locking tube 5 is alleviated. A second aspect of the present invention is characterized in that, in the first aspect, means for moving a component into the guide tube is installed in the vicinity of an end portion of the introduction passage. A force is applied, which allows the part to be smoothly transferred into the guide tube. Claim 3
According to claim 1, the tip end portion of the supply rod is a gutter-shaped release portion, and the release portion is opposed to the opening portion of the introduction passage and the holding means for holding the component at the tip end portion of the supply rod. Is installed,
The components received by the control surface are moved into the guide cylinder as they are, are accommodated in the releasing portion, and at the same time, the components are held in the releasing portion so as not to drop from the releasing portion. According to a fourth aspect of the present invention, the temporary locking means is formed by elastically supporting a member projecting into the tube in the guide tube or the locking tube according to the first aspect. Instead of the tip of the stop tube, it is temporarily locked to another place in the form of an elastic protrusion. Claim 5
3. The locking pipe according to claim 1, wherein a temporary locking means is formed by reducing the inner diameter of the locking tube at or near the tip of the locking tube. It is temporarily locked at the small diameter part. Claim 6
Has an advancing / retreating type feed rod installed in the guide tube, and a locking tube for a component having the function of a movable electrode is joined to the tip of the guide tube, and the introduction passage of the component is oriented in an angle with the guide tube. When installed and opened in the guide tube, a control surface for optimizing the approach speed of parts is formed in the middle of the introduction passage. This is achieved on the control side, and then the parts are directly fed into the guide tube through the introduction passage. A seventh aspect of the present invention is that, in the sixth aspect, the introduction passage is bent, and the control surface is formed in the bent portion. The control surface is formed by using the shape of the bent portion. , Here, the approach speed is optimized as in the tactics. According to an eighth aspect of the present invention, the control surface according to the sixth aspect is installed near the opening of the introduction passage, and the component is fed into the guide tube after the approach speed is optimized. Go away.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of the present invention will be described with reference to the illustrated examples. Since parts other than the introduction hole 10 and the supply hose 11 of FIG. 1 are part of the embodiment of the present invention, the embodiment will be described in addition to the above description. A receiving hole 20 is formed in the supply rod 2, and a taper portion 21 is formed in the opening. As a locking means for the component installed in the receiving hole 20, a leaf spring is exposed on the inner surface of the locking hole 20 and the component is sandwiched by the elastic force of the leaf spring, or similarly on the inner surface of the receiving hole 20. Various means can be adopted such as exposing the steel ball, supporting this steel ball with a coil spring, and elastically holding the part with the steel ball. Here, an example of the simplest magnet (permanent magnet) is shown. It was The magnet is designated by reference numeral 22 and is fitted in the innermost portion of the receiving hole 20.

The outer surface of the guide cylinder 1 is scraped off to remove the flat surface portion 2.
3 is formed, and a block body 24 having a substantially rectangular parallelepiped shape is welded thereto. The block body 24 has a component introduction passage 2
5 is formed and communicates with the opening 26 opened in the flat portion 23. A control surface 27 is formed at the end of the introduction passage 25 for optimizing the entry speed of components. This control surface 27 has openings 2 as can be seen from FIGS.
The surface formed in 6 and the surface formed in the block body 24 are smooth and continuous, and it is even better if the surface is subjected to heat treatment in consideration of abrasion due to impact of parts. Instead of being flat, it is also possible to make it concave if the part is an iron bolt 16 as shown. Air injection is adopted as a means for smoothly moving the components from the passage 25 into the guide cylinder 1. This is composed of ejection holes 28 opened in the block body 24 toward the inside of the passage 25, a distribution chamber 29 communicating with the ejection holes 29, and an air hose 30 opening to the distribution chamber 29. In addition,
To form the distribution chamber 29, a thick plate 31 is fixed to the block body 24 with bolts 32, and the thick plate 31 has a concave distribution chamber 29. The bolt 16 is not shown in FIG. 2 for easy understanding.

A joint pipe 33 communicating with the passage 25 is welded to the upper portion of the block body 24, and a supply hose 34 is joined thereto, which extends from a parts feeder (not shown). As is apparent from FIG. 1, the joint pipe 33 and the introduction passage 25 are aligned on a straight line, and the axis of the joint pipe 33 and the axis of the guide cylinder 1 intersect at an acute angle. In other words, the introduction passage 25 and the guide cylinder 1 are installed so as to form an acute angle.

Reference numeral 39 denotes a welding current cable connected to the guide cylinder 1, and a fixed electrode 40 is arranged coaxially with the locking tube 5, and a steel plate component 41 as a counterpart component is mounted thereon. It is placed. Insulation is appropriately provided so that the current from the cable 39 does not flow to unnecessary portions, but the illustration is omitted here.

The operation of the embodiment shown in FIGS. 1 and 2 will be described. The bolt 16 that has been vigorously transported in the supply hose 34 enters the passage 25 and collides with the control surface 27. Then, the bolt 16 is continuously moved into the guide cylinder 1 by the air from the ejection holes 28 and falls into the locking tube 5, and the flange 18 is caught by the locking projection 9 and stopped. After that, when the supply rod 2 descends, the shaft portion 17 relatively enters into the receiving hole 20, and the magnet 2
You will receive a suction power of 2. And the supply rod 2
When the tip of comes in contact with the flange 18 and pushes it down further,
The flange 18 strongly hits the locking projection 9 to elastically expand the tip of the locking tube 5, and when the flange 18 passes the locking projection 9, the advance of the supply rod 2 is stopped, and the state of FIG. Becomes Then, the operation of the air cylinder 13 causes the entire apparatus such as the guide tube 1 and the locking tube 5 to descend, the raised portion 19 of the bolt 16 is pressed against the steel plate component 41, and the cable 3
When energized from 9, the electric current flows from the flange 18 to the steel plate component 41 and the fixed electrode 40 via the guide tube 1 and the locking tube 5, and the projection welding by electric resistance is completed.
When performing stud welding instead of the above projection welding, the raised portion 19 is allowed to stand still in the immediate vicinity of the steel plate component 41, and then a welding current is applied, and an arc is generated there to form a melted portion on the raised portion and the steel plate component. , Then flange 1
8 is pressed against the steel plate part to complete welding. In this case, a shield gas is used, but the structure required for it is not shown. When the approaching direction of the component is inclined with respect to the control surface 27 as shown in FIG. 1, a leftward force acts on the bolt 16 hitting the control surface 27, so that the air velocity from the ejection hole 28 is increased. Can be weakened or stopped. Even if the bolt 16 temporarily locked in the locking tube 5 is inclined and the tip of the shaft portion 17 is in contact with the inner surface of the locking tube 5, the taper portion 21 is provided in the receiving hole 20 of the supply rod.
Since the tapered portion 21 scoops up the shaft portion 17, the shaft portion 17 enters the receiving hole 20.

In order to increase the leftward force as described above, it is preferable to construct the inclined control surface 27 as shown in FIG. In this case, it is possible to omit the means for moving the parts into the guide cylinder.

The control surface of FIGS. 1 and 3 is an example in which the bolt is decelerated without hitting it and stopping.
In this case, since the control surface 27 is inclined in the direction orthogonal to the approaching direction of the component, that is, the inclination opposite to that in FIG. 3, the bolt 16 is temporarily stopped on the control surface 27. Therefore, in this embodiment, the air cylinder 35 is attached to the block body 24, and the piston 16 advances to move the bolt 16 into the guide cylinder 1.

In the embodiment described above, the device is in such a position that the parts fall, but when the guide tube and the locking pipe are installed horizontally or in a position close to that, the air injection shown in FIG. 4 is performed. Open the hole 37 in the guide cylinder 1,
The parts transferred into the guide cylinder 1 are immediately conveyed to the locking tube 5 by the air blown out from the injection holes 37. In this case, the passage 25 is located on the lower side to allow the control surface 27 to perform the initial operation.

Although the insulating structure for the welding current has been described above, the illustration thereof is omitted here because it can be easily implemented by an ordinary method. Further, the illustration of the air hose to be connected to the air cylinder is omitted, and the sequence required for operation can be easily implemented by a normal air electromagnetic switching valve or control circuit.

Referring to FIGS. 6 and 7, these have a so-called tapered shape in which there is no locking projection in FIG. 1 and the diameter of the locking tube 5 becomes smaller toward the tip thereof, that is, the control surface 27. After being decelerated by
Touches the inner surface of the locking tube 5 and is stopped. When the supply rod 2 descends there, the shaft portion 17 relatively enters into the receiving hole 20, and the tip portion of the supply rod 2 contacts the back surface of the flange 18. As the supply rod 2 further descends, the flange 18 pushes the locking tube 5 apart, and the flange 18 stops at a position slightly below the tip of the locking tube 5 and then stops. When returned slightly, the state shown in FIG. 7 is obtained, and the bolt 16 is held at the position shown in FIG. 7 by the attractive force of the magnet 22.

In the above-described embodiment, the locking projection 9 or the locking tube 5 is tapered at the end of the locking tube 5, but the locking tube 5 shown in FIG. A member protruding inside the pipe 5 or the guide pipe 1, for example, a part of a steel ball is exposed to elastically support the steel ball. That is, four tapered holes 42 are opened in the circumferential direction at equal intervals in the circumferential direction of the locking tube 5, steel balls 43 are fitted into each of them, and a part thereof is projected into the locking tube 5, and a coil spring 44 is used. The steel ball 43 is given elasticity. Therefore, the annular member 4
5 is fixed to the cap nut 7 with the bolt 46, the coil spring 44 is housed in the hole 47 opened in the diameter direction of the annular member 45, and the plug bolt 48 prevents the coil spring 44 from coming off. When the bolt 16 whose movement speed is controlled by the control surface 27 descends in the guide cylinder 1, the four steel balls 43 from which the flange 18 projects
It is caught in and paused. The supply rod 2 descends there, the flange 18 forcibly retracts the steel ball 43, and thereafter, welding is performed in the same process as described above.

Next, the embodiment shown in FIGS. 9 and 10 will be described. Although the above-mentioned supply rod is of the type in which the receiving hole 20 is formed, in this embodiment, the tip end of the supply rod has a gutter shape. The bolt 16 is moved in the diametrical direction of the supply rod 2, and the shaft portion 17 is held by the supply rod 2. That is, the trough-shaped portion 49 is formed by cutting out the distal end portion of the supply rod 2, a concave groove portion 50 is formed, and the release portion 51 is opposed to the opening portion 26 of the introduction passage. The gutter-shaped portion 49 is provided with a means for holding components. The simplest one is that the magnets 52, 53 are embedded in the tip of the supply rod 2 as shown in the drawing. The installation position of these magnets is such that the bolt 16 is sucked into the gutter and is raised above the supply rod 2. Are selected. In order to assist the attraction force, a magnet 54 is attached to the guide cylinder 1 as shown by a two-dot chain line in the figure.
May be attached. The other structure in this embodiment is
Since it is similar to that of FIG. 1, the same reference numerals are displayed and detailed description is omitted. What is important in arranging the magnets is to place the magnets away from the release portion 51 above the concave groove portion 50 like the magnet 53.
By doing so, the bolt 16 receives the force of being pulled upward, the back surface of the flange 18 contacts the tip portion of the supply rod 2, and the relative position of the supply rod and the bolt is determined. When the bolt 6 descends in the introduction passage, is received by the control surface 27, and is then transferred into the guide cylinder 1 by the air from the ejection port 28, the shaft portion 17 of the bolt 16 is opened by the opening portion 2.
6 is drawn into the trough-shaped portion 49 by the attraction force of the magnets 52 and 53. Then, the bolt 16 is pulled upward by the direction of attraction of the magnet 53,
Therefore, the flange 18 is in contact with the tip of the supply rod 2.

Next, the embodiment of FIG. 11 will be explained. This is because the control surface 27 is provided in the introduction passage 25, and the introduction passage 25 is actually bent at the bent portion 55. The control surface 27 is formed in this portion as shown in the figure. Here, the magnet 5 is provided below the control surface 27.
6 is buried, and it is fixed by bolts 57 from the outside. In order to lower the bolt 16 stopped on the control surface 27 toward the opening 26, an ejection hole 58 for compressed air is opened and an air hose 59 is connected thereto. Control surface 2
An advancing / retreating type control member 60 is installed slightly downstream of 7, and is constituted by a piston rod of an air cylinder 61 attached to the outside. The control surface 27 is located as close to the opening 26 as possible to prevent the bolt 16 leaving the control surface 27 from becoming excessively fast.

The operation of this embodiment will be described. The bolt 16 descending through the introduction passage 25 is received by the control surface 27 and attracted onto the control surface 27 by the attractive force of the magnet 56. Then, compressed air is blown from the ejection holes 58 into the bolts 16
When the bolt 16 is injected into the control surface 27, the bolt 16 moves away from the control surface 27 and descends in the rear introduction passage 25 to open the opening 2
6 enters the guide cylinder 1. Control member 6
Numeral 0 temporarily locks the bolt 16 that has left the control surface 27, and if it protrudes as shown by the chain double-dashed line, it functions as a temporary lock and controls the supply of bolts in accordance with the welding cycle. To fulfill. If such control is not necessary, the control member 60 may be omitted. Further, if the descending speed of the bolt 16 of the magnet 56 is gentle, this may be eliminated.

Next, the embodiment of FIG. 12 will be described. Here, the control surface is not installed in the introduction passage 25 which is a stationary member, but the advancing / retreating control member 62 is used to optimize the speed of parts. The piston rod of the air cylinder 63 attached to the outside serves as the control member 62. Although the control member 62 is installed in the bent portion 55 of the introduction passage 25, it may be installed in the vicinity of the opening 26 as shown by the chain double-dashed line. The bolt 16 is temporarily locked by the control member 62 as shown by the chain double-dashed line, and the lowering speed is optimized.

[0022]

As described in the above embodiments, according to the present invention, since the parts are temporarily stopped on the control surface or the moving speed is reduced on the control surface, the locking pipe is not damaged or worn. It is possible to allow the locking tube to enter at an appropriate speed so that the locking tube does not enter, and thus it is possible to improve the durability of the locking tube. Specifically, it prevents the locking projections and the tapered inner surface of the locking tube from being abnormally worn or damaged. Since the passage for introducing the component into the guide cylinder is arranged so as to form an acute angle with the guide cylinder and along the guide cylinder, a control surface is formed at the end of the guide cylinder to guide the passage from the guide cylinder. The distance to the inside of the cylinder becomes the shortest, and therefore, quick component transfer is facilitated. Further, since the control surface is configured by utilizing the portion having an acute angle, the control surface itself can be easily installed in terms of space. Since the means for moving the parts into the guide cylinder is installed near the end of the introduction passage, the decelerated parts are surely transferred into the guide cylinder, and highly reliable operation is realized. The tip of the supply rod is a gutter-shaped opening, the opening is opposed to the opening of the introduction passage, and the means for holding the component is installed at the tip of the supply rod. The decelerated part is moved in the diametrical direction of the guide cylinder and immediately accommodated in the trough-shaped part, so that a quick transition can be surely obtained. Since the temporary locking means is a member protruding into the guide tube or the locking tube and is elastically supported, it is possible to install the temporary locking means at a required position, that is, at an optimum position. It is possible to optimize the advance operation of. Even when the inner diameter of the locking tube is made small, that is, even when the component is temporarily locked to the inner surface of the locking projection or the tapered portion, highly durable operation can be secured as the temporary locking means. When the combination of the guide tube and the introduction passage is restricted due to space problems, the control surface is installed in the middle of the introduction passage to make the joint between the introduction passage and the guide tube a simple structure. be able to. Further, by installing the control surface in the bent portion of the introduction passage, since the installation is performed at a position apart from the guide tube as shown in FIG. 11, a space problem can be avoided. Since the control surface is located near the opening,
The parts off the control surface do not overspeed and serve their initial purpose. The effects that can be emphasized from the structure of the embodiment are listed. In the case of supplying the parts downward, the supply rod is formed with a receiving hole for the parts and the holding means for the parts is installed in this hole. Even in the case, parts do not drop carelessly, which is effective for accurate supply. By utilizing air injection as a means for moving the parts into the guide cylinder, the force necessary for the movement can be applied to the parts without giving any geometrical deformation to the shape of the introduction passage. Is extremely advantageous. In the gutter-shaped part formed at the tip of the supply rod, by installing the magnet so that the bolt is pulled in behind the supply rod, the relative position of the bolt and the tip of the supply rod as described above. Can be set accurately. When the device of the present invention is used as a stud welder, a locking tube as shown in the figure is generally adopted. The locking tube has durability in elastic action and locking. Although abrasion resistance or heat resistance is required for the protrusions, the problems of elasticity and heat can be solved by improving the material, but the problem of wear is that the penetration speed of the part is extremely high and the mass of the part is large. Although it has been difficult to solve because of such things, by decelerating the approach speed of parts by the present invention to optimize,
A stud welder with high durability can be obtained. Further, when utilizing the present invention as projection welding of a bolt with a flange, the back surface of the flange is pushed by the tip portion of the locking tube, and the raised portion for welding of the flange is pressed against the counterpart steel plate component. Since the welding is performed by energizing, the introduction of bolts to the locking tube and the pressing of the flange by the locking tube can be achieved by a series of operations, and efficient and highly accurate projection welding is realized. By arranging the control surface on the bent portion and arranging the magnet in the vicinity of the bent portion, it is easy to install the control surface and it becomes possible to firmly lock the component to the control surface. In particular, since the control surface, magnets, advancing / retreating control members, etc. are centrally arranged in the bent portion, they can be arranged well in a location apart from the guide tube, and the connectivity between the guide tube and the introduction passage is improved. .

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line (2)-(2) of FIG.

FIG. 3 is a partial vertical cross-sectional side view of another embodiment.

FIG. 4 is a partial vertical cross-sectional side view of another embodiment.

FIG. 5 is a partial vertical cross-sectional side view showing a state in which the supply rod has advanced.

FIG. 6 is a partial vertical cross-sectional side view of another embodiment.

FIG. 7 is a partial vertical cross-sectional side view showing a state in which the bolt of FIG. 6 is held.

FIG. 8 is a partial vertical sectional side view of another embodiment.

FIG. 9 is a partial vertical cross-sectional side view of another embodiment.

FIG. 10 is a partial three-dimensional view showing the tip portion of the supply rod of FIG.

FIG. 11 is a partial vertical sectional side view showing another embodiment.

FIG. 12 is a partial vertical sectional side view showing another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 guide cylinder 2 supply rod 16 parts 5 locking tube 25 introduction passage 27 control surface 28, 36 means for moving parts 49 trough-shaped parts 52, 53 holding means 43 projecting member 55 bent part

Claims (8)

[Claims] 1. An advance / retreat type supply rod is installed in the guide cylinder, and a locking tube for a component having a function of a movable electrode is joined to the tip of the guide cylinder, and the introduction passage of the component forms an acute angle with the guide cylinder. A welding apparatus, wherein a control surface for optimizing an entry speed of a component is formed at an end portion of an introduction passage, which is installed in a guide direction and opened in a guide cylinder. 2. The welding device according to claim 1, wherein a means for moving a component into the guide tube is provided near an end portion of the introduction passage. 3. The feed rod according to claim 1, wherein a tip end portion of the supply rod is a gutter-shaped release portion, and the release portion is opposed to the opening portion of the introduction passage and the component is held at the tip end portion of the supply rod. The welding device is characterized in that holding means is installed. 4. The welding device according to claim 1, wherein the guide cylinder or the locking pipe is elastically supported by a member projecting into the pipe to form a temporary locking means. 5. The welding apparatus according to claim 1, wherein a temporary locking means is formed at or near the tip of the locking tube by reducing the inner diameter of the locking tube. 6. A forward / backward supply rod is installed in the guide cylinder, a locking tube for a component having a function of a movable electrode is joined to the tip of the guide cylinder, and an introduction passage of the component forms an acute angle with the guide cylinder. A welding device, wherein a control surface for optimizing an approach speed of a component is formed in the middle of an introduction passage, which is installed in an orientation so as to open in a guide cylinder. 7. The welding device according to claim 6, wherein the introduction passage is bent, and a control surface is formed on the bent portion. 8. The welding device according to claim 6, wherein the control surface is installed near the opening of the introduction passage.