JPH01122670A - Welding equipment for pipe manufacturing machine - Google Patents

Abstract

PURPOSE:To prevent the occurrence of defective welding and to improve product quality by detecting each edge of a belt-like member by a couple of edge detectors in the vicinity of the upstream side of sizing dies and moving a movable supporting member so that the deviation of detected signals attains zero. CONSTITUTION:The edge detector 20a detects the distance from a detecting point A to one edge 4a in the axial direction of the beltlike member 4. The edge detector 20b also detects the distance from a detecting point B to the other edge 4b in the width direction of the belt-like member 4 in the same way. The outputs of the edge detectors 20a and 20b are proportioned to the distances (a) and (b) in the horizontal direction between the detecting points A and B and the edges 4a and 4b. The outputs of these edge detectors 20a and 20b are inputted to a controller 40 which produces a deviation signal from these signals. Further, the controller 40 performs PID processing on the deviation signal and produces a control signal of a servomotor 31 and controls the motor 31 and the distances (a) and (b) are equalized to each other. By this method, the occurrence of the defective welding and a pinhole is prevented and the product quality is improved.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a pipe making machine that manufactures a pipe by continuously forming a band member into a tubular shape. The present invention relates to a welding device that welds both ends in a direction.

(Prior art and its problems) For example, a strip member made of copper, steel, aluminum, titanium, etc. is formed into a tube shape, and both widthwise ends of the strip member are welded to each other to continuously manufacture a tube. In a pipe making machine, it is difficult to always maintain the abutting surface at a constant position at the welding position, and the position of the abutting surface changes over time to some extent due to rolling. Therefore, if the position of the welding torch is not adjusted, the butt surfaces cannot be accurately welded, resulting in defective welding and pinholes. It was configured to be operated manually.

However, in such a conventional configuration, the operator visually monitors the relationship between the tip of the welding torch and the butt surface, and
It was necessary to manually adjust the position of the welding torch when a certain amount of deviation occurred, which was an obstacle to saving labor, and at the same time, there was a limit to pipe production speed, and furthermore, due to adjustment errors, welding This has the disadvantage that defects, pinholes, etc. may occur, leading to a deterioration in the quality of the tube.

(Means for Solving the Problems) In order to solve the above-mentioned conventional problems, a welding device for a pipe making machine according to the present invention includes a forming machine that forms a continuously supplied strip member into a substantially tubular shape, and a welding device for a pipe making machine of the present invention. In a pipe making machine having a sizing die located on the downstream side of the forming machine and for abutting both widthwise ends of the band-shaped member formed into a substantially tubular shape, the sizing die is positioned downstream of the sizing die and adjacent to the downstream side of the band-shaped member. The welding device is equipped with a welding torch for welding both ends in the width direction that are abutted against each other, the welding device is provided with a welding torch that welds both ends in the width direction that are abutted against each other, and the device generates a detection signal according to the distance to each edge in the width direction of the strip member at a position near the upstream side of the sizing die. A movable support that supports a set of two electromagnetic induction type edge detectors and the welding torch and is capable of reciprocating a predetermined distance in a direction substantially orthogonal to the traveling direction of the belt-shaped member. parts and
A drive device that drives the movable support member, and a control device that controls the drive device to move the movable support member so that the deviation of the detection signals from the two edge detectors becomes zero, The tip of the welding torch is configured to follow both ends of the band-shaped member that are abutted against each other.

(Function) A pair of electromagnetic induction type edge detectors each output a detection signal corresponding to the distance to each edge in the width direction of the strip member at a position near the upstream side of the sizing die. Then, the control device controls the drive device to move the movable support member so that the deviation of the detection signals from the two edge detectors becomes zero. Therefore, the tip of the welding torch attached to the movable support member together with the edge detector follows both ends of the strip member in the width direction that are abutted against each other.

(Example) Hereinafter, an example of the present invention will be described based on FIGS. 1 to 7.

FIG. 4 is a schematic overall configuration diagram of a pipe-making machine equipped with a welding device according to an embodiment of the present invention, and is an example of pipe-making a cable sheath. In FIG. 4, 1 is a cable supply, and a cable body 2 to be sheathed is wound around this cable supply 1. Reference numeral 3 denotes a tape supply, and a band-shaped member 4 that is formed into a tube and becomes a sheath is wound around the tape supply 3, and this band-shaped member 4 is made of, for example, copper, steel, aluminum, or titanium. . The strip member 4 pulled out from the tape supply 3 is cleaned by a tape washer 5, and both ends in the width direction are cut off by a slitter 6 to have a predetermined width. The removed waste on both ends in the width direction is collected by the removed part winder 7.
The strip member 4 having a predetermined width is formed into a substantially tubular shape by a forming machine 8. During this molding, the cable main body 2 pulled out from the cable supply 1 is placed inside the strip member 4.
is inserted. Therefore, the substantially tubular strip 4 covers the cable body 2. This strip member 4 is formed into a tubular shape with a predetermined diameter by a sizing die 9 located downstream of the molding machine 8 in the direction of movement of the strip member 4 by butting both widthwise ends against each other. A welding device 10 is disposed above the sizing die 9, and this welding device 10 welds the abutting surfaces at both widthwise ends of the strip members 4 abutted against each other by the sizing die 9.

Welding device 10 with cable main body 2 inserted inside
The welded strip member 4 is taken up by a take-up machine 11, corrugated by a corrugation machine 12 to become a corrugated tubular sheath, and wound up by a winder 14 via a damper 13.

In this way, with the cable main body 2 inserted inside, the band member 4 is continuously formed into a tube and a sheath is applied. In FIG. 4, reference numerals 15 and 16 indicate rollers that guide the cable body 2.

FIG. 1 is a front view of the main parts of the welding device 10, and FIG. 2 is a side view of the same. The welding torch 18 that generates an arc for welding the abutting surfaces at both ends of the strip member 4 in the width direction is shown in FIG. It is located near the downstream side of the sizing die 9 and is fixed to the movable support member 19. A pair of edge detectors 20a and 20b are located near the upstream side of the sizing die 9, and output signals corresponding to the distances to the edges of both ends of the strip member 4 in the width direction. These edge detectors 20a, 20b are fixed to a bracket 21. Note that the upstream and downstream sides here are
The direction of movement of the strip member 4 indicated by the arrow in FIG. 2 is used as a reference. Further, the tips of the welding torch 18 and the edge detectors 20a, 20b are close to the band member 4. The bracket 21 has a protruding portion on the back surface of the upper end portion of the bracket 21.
3, and one end of the screw shaft 23 has a knob 23a.
is installed. That is, by turning this knob 23a, the screw shaft 23 rotates around the axis, and the bracket 21 moves in the horizontal direction perpendicular to the traveling direction of the band-shaped member 4, so that the edge detectors 20a, 20b move in the horizontal direction. You can fine-tune the position of. The frame body 22
The protrusion on the back is screwed into a vertically extending screw shaft 26 rotatably supported by the frame 25, and a knob 26a is attached to the upper end of the screw shaft 26. That is, by turning this knob 26a, the screw shaft 26 rotates around the axis and the frame body 22 moves in the vertical direction, so that the vertical positions of the edge detectors 20a and 20b can be finely adjusted. . The frame body 25 is the bracket 2
7 to the movable support member 19, and therefore the welding torch 18 and the edge detectors 20a, 2
0b moves together with the movement of the movable support member 19. A vertical screw 28 is screwed into the upper end of the frame 22, and a knob 28a is attached to the upper end of the screw 28. The tip of this screw 28 comes into contact with the upper surface of the protrusion on the rear surface of the upper end of the bracket 21, thereby fixing the bracket 21.

FIG. 3 is a plan view of the welding device 10, in which a servo motor 31 with a harmonic drive as a drive device is fixed on a fixed frame 29 via a bracket 30.
The output shaft 31a of this servo motor 31 is connected to the coupling 3
2 is connected to one end of the screw shaft 33. This threaded shaft 33 has a male screw threaded on the outer periphery of the intermediate portion, and the other end is rotatably supported around the axis by a bearing (not shown), and is orthogonal to the traveling direction of the band-shaped member 4. arranged along the horizontal direction. A nut 34 is screwed into the intermediate portion of this screw shaft 33, and this nut 34 is connected to the bracket 3.
5 to the movable support member 19. A cylindrical body 36 is slidably fitted to the other end of the screw shaft 33, and this cylindrical body 36 is fixed to the movable support member 19 via a bracket 37. Therefore, by driving the servo motor 31, the rotational force of the output shaft 31a is transmitted to the screw shaft 33 via the coupling 32, which moves the nut 34 in the axial direction of the screw shaft 33, so that the movable support The member 19 moves together with the nut 34 in a horizontal direction perpendicular to the traveling direction of the strip member 4. Note that 38 is a sprocket that is fitted and fixed to one end of the screw shaft 33.

FIG. 5 is a block diagram of the electric circuit of the welding device 10,
A control device 40 comprising, for example, a microcomputer controls the servo motor 31 based on detection signals from the edge detectors 20a and 20b.

Next, the effect will be explained. The edge detector 20a detects the distance from the detection point A to one edge 4a of the strip member 4 in the width direction, as shown in FIG.

The edge detector 20b similarly detects the distance from the detection point B to the other edge 4b of the strip member 4 in the width direction.

That is, the edge detectors 20a and 20b
An eddy current is generated by electromagnetic induction at the widthwise end of the eddy current, and the state of this eddy current is detected at detection points A and B by electromagnetic induction. be. Therefore, the edge detectors 20a, 2
The output of 0b is approximately proportional to the horizontal distances a and b between the detection points A and B and the edges 4a and 4b. The outputs of the edge detectors 20a, 20b are input to the control device 40, and the control device 40 creates a deviation signal as shown in FIG. 7 from these signals. That is, the edge detector 20a
The output signal of corresponds to the distance a, and the output signal of the edge detector 20
Since the output signal b corresponds to the distance, a signal corresponding to the distance a-b is created from these signals. Furthermore, the control device 40 performs PID processing on this deviation signal to create a control signal for the servo motor 31, and controls the servo motor 31. For example, if the strip member 4 rolls in the clockwise direction in FIG.
0 controls the servo motor 31 to move the output shaft 31a from a to b.
is rotated by a predetermined angle in a predetermined direction according to the value of . Of course, this rotation angle may exceed 360 degrees or multiples thereof.

As a result, the screw shaft 33 rotates, one movable support member moves together with the nut 34, and the edge detectors 20a, 20b
moves to the right side in FIG. 6 together with the movable support member 19.

As a result, distance a and distance s become equal, and a-bwO
become. By the way, the welding torch 18 also has a movable support member 19.
Since the movable support member 19 moves, the welding torch 18 also moves together, and as a result, the welding torch 1
The tip of 8 always follows the abutting surface of edge 4a and edge 4b. Note that at the positions of the edge detectors 20a and 20b,
Since the welding torch 18 is located upstream of the sizing die 9, there is a slight gap between the edge 4a and the edge 4b as shown in FIG. Therefore, the edge 4a and the edge 4b are butted against each other and there is no gap. Contrary to the above, the band member 4
When rolling counterclockwise in Figure 6, a
The value of -b increases in the negative direction, and the movable support member 19 moves in the opposite direction to the above due to the operation of the servo motor 31 controlled by the control device 40, resulting in a-b-0.

Note that before operating the welding device 10, the knob 26a
to detect the detection points A of the edge detectors 20a and 20b,
Accurately finely adjust the vertical distance between B and the edges 4a, 4b of the strip member 4 to a predetermined distance of about 1.5 degrees, for example, and operate the knob 23a to detect the edge detector 20a.
, 20b, and the position of the axis of the welding torch 18 in the left-right direction in FIG. 20a and 20b are fixed.

In this way, the welding torch 18 and the edge detectors 20a, 20b are fixed to the movable support member 19, and a pair of edge detectors 20 are arranged near the upstream side of the sizing die 9.
a, 20b to detect the edges 4a, 4b of the strip member 4, and the control device 40 controls the servo motor 31 to move the movable support member 19 so that the deviation becomes zero, so direct detection is possible. Edge 4a that is difficult to
As a result, the abutting surface between the edge 4b and the end edge 4b can be detected accurately,
Therefore, the tip of the welding torch 18 is always accurately aligned with the edge 4a.
Since it can be made to follow the abutting surface of the end edge 4b, it is possible to reliably prevent welding defects and pinholes from occurring, thereby improving quality. At the same time, it is possible to improve production by saving labor and increasing pipe manufacturing speed. It is possible to improve sexual performance. In addition, since electromagnetic induction type sensors are used as the edge detectors 20a and 20b, unlike the case where optical type sensors are used, even if foreign matter such as dust, water, oil, etc. is attached to the sensor or the detected part, Even if the material surface of the detected part is glossy, accurate detection can be performed without any problems and malfunctions will not occur.

Moreover, optical sensors have problems such as being affected by ambient light and having a limit on the bending radius of the fiber unit, which increases transmission loss. No problems will occur.

(Another embodiment) In the above embodiment, the servo motor 3 is used as the drive device.
1 was used, but the present invention is not limited to such a configuration, and other devices such as a cylinder device or a piezoelectric element may be used as the drive device.

Further, in the above embodiment, the movable support member 1-9 was linearly moved in the horizontal direction perpendicular to the traveling direction of the strip member 4, but the present invention is not limited to such a configuration; The support member 19 may be configured to move on an arc coaxial with the axis of the band-shaped member 4.

Further, in the above embodiment, an example was explained in which a corrugated pipe is made using the corrugating machine 12, but the welding device of the present invention can also be applied to a pipe making machine that makes ordinary pipes other than corrugated pipes. Of course, it can be used.

Further, in the above embodiment, an example was explained in which a pipe constituting a cable sheath is formed, but the welding apparatus of the present invention can be used to form any other pipe from the strip member 4, such as a conductor of a coaxial cable, etc. Of course, it is also used for making pipes.

(Effects of the Invention) As explained above, according to the present invention, a welding die and a set of two edge detectors are fixed to a movable support member, and two edge detectors are fixed in the vicinity of the upstream side of the sizing die. Each edge of the strip member is detected by a pair of edge detectors, and the drive device is directly controlled by the control device to move the movable support member so that the deviation of the detection signal becomes zero. As a result, it is possible to accurately detect the abutting surfaces of both ends of a strip member, which is difficult to detect, and the tip of the welding torch can always accurately follow the abutting surfaces of both ends, thereby preventing welding defects and pinholes. It is possible to reliably prevent this occurrence and improve quality, and at the same time, it is possible to improve productivity by saving labor and increasing the pipe manufacturing speed. Therefore, = 16 - For example, when the welding device of the present invention is used to manufacture conductors for coaxial cables, the electrical characteristics of the coaxial cables will not be disturbed by poor welding, and the coaxial cables of excellent quality can be stably produced. Can be manufactured. In addition, since we used an electromagnetic induction sensor as an edge detector, unlike when using an optical sensor, even if there is foreign matter such as dust, water, oil, etc. attached to the sensor or the detected part, Even if the surface of the material is glossy, accurate detection can be performed without any problems and malfunctions will not occur. Moreover, optical sensors have problems such as being affected by ambient light and having a limit on the bending radius of the fiber unit, which increases transmission loss. No problems will occur.

[Brief explanation of the drawing]

Fig. 1 is a front view of essential parts of a welding device according to an embodiment of the present invention, Fig. 2 is a side view of the same, Fig. 3 is a plan view of the welding device, and Fig. 4 is a construction equipped with the welding device. Fig. 5 is a block diagram of the electric circuit of the welding equipment, Fig. 6 is an explanatory diagram of the detection operation of the edge detector, and Fig. 7 is an explanatory diagram of the deviation signal of the edge detector. be. 4... Band member, 8... Molding machine, 9... Sizing die, 10... Welding device, 18... Welding torch, 19... Movable support member, 20a, 20b... Edge Detector, 31... Servo motor (drive device), 40
...Control device patent applicant Mitsubishi Cable Industries, Ltd.

Claims (3)

[Claims] (1) A forming machine that forms a continuously supplied band-like member into a substantially tubular shape, and a sizing die that is located downstream of this forming machine and abuts both widthwise ends of the band-like member that is formed into a substantially tubular shape. a welding device comprising a welding torch for welding both ends of the strip member in the width direction that are abutted against each other at a position near the downstream side of the sizing die, the welding device comprising: A set of two electromagnetic induction edge detectors each outputting a detection signal corresponding to the distance to each edge in the width direction of the strip member at a nearby position, and supporting these edge detectors and the welding torch. a movable support member capable of reciprocating a predetermined distance in a direction substantially perpendicular to the traveling direction of the belt-shaped member; a drive device for driving the movable support member; and a drive device for controlling the drive device to control the two edge detectors. and a control device for moving the movable support member so that the deviation of the detection signal from Welding equipment for pipe making machines. (2) The welding device for a pipe-making machine according to claim 1, wherein the movable support member is configured to be able to reciprocate in a direction exactly orthogonal to the traveling direction of the strip member. (3) The welding device for a pipe making machine according to claim 1, wherein the movable support member is configured to be able to reciprocate on an arc concentric with the tubular band member.