JP5521629B2 - Method and apparatus for positioning welding torch in automatic welding apparatus - Google Patents

Description

  The present invention is used to arrange a welding torch in an automatic welding apparatus used for welding a large number of branch pipes in a circumferential direction and a longitudinal direction of a mother pipe so as to correspond to a welding portion between the mother pipe and the branch pipe. The present invention relates to a welding torch positioning method and apparatus in an automatic welding apparatus.

  One type of header (heading) in a boiler or the like is a type in which a plurality of branch pipes are connected to the outer peripheral surface of the mother pipe in the circumferential direction and the longitudinal direction (axial direction).

  When manufacturing this type of header, a plurality of circumferentially arranged mother pipes at one circumferential position, for example, at the upper end position of the outer circumferential face, are arranged at a required interval in the longitudinal direction of the mother pipe. A branch pipe is welded and attached, and then the mother pipe is rotated at a required angle in the circumferential direction and then newly arranged at a position at the upper end side of the outer peripheral surface of the mother pipe at a required interval in the longitudinal direction. A method is often used in which a plurality of branch pipes are attached in the circumferential direction and the longitudinal direction of the outer peripheral surface of the mother pipe by welding and attaching a plurality of branch pipes, and then repeating the above procedure in sequence.

  In addition, a welding operation for attaching branch pipes arranged at a predetermined interval in the longitudinal direction of the mother pipe to the upper end side position on the outer peripheral surface of the mother pipe arranged sideways is automated using a robot equipped with a welding torch. There has been proposed an automatic welding apparatus which can be used.

  When the welding operation of the branch pipe to the mother pipe as described above is automated using a robot, the welding torch provided for the robot is connected to the welding portion between the branch pipe and the mother pipe in the entire circumferential direction. Therefore, it is necessary to move the welding position of the branch pipe and the main pipe in advance by the robot, and the welding position is determined by the welding torch according to the detected position of the welding position. It is important to make it.

  For this purpose, for example, a reference branch pipe selected from a plurality of branch pipes arranged in the longitudinal direction of the mother pipe, using a tip provided at the tip of a welding torch provided for the robot as a probe, The position of the mother pipe in the vicinity thereof is detected by touch sensing, and based on the position data about the reference branch pipe and the arrangement pitch of each branch pipe arranged in the longitudinal direction of the mother pipe, the other branch pipes, Conventionally, a method for calculating a position of a mother pipe near a branch pipe and determining a welding position by a welding torch has been proposed (see, for example, Patent Document 1).

  In addition, when a probe (stylus sensor) is provided near the welding torch provided in the robot to weld the mother pipe and the branch pipe, the welding object temporarily attached to a predetermined position of the mother pipe in advance. For the branch pipe to be touched by the probe, based on the detection result, the branch pipe to be welded is arranged vertically and the moving direction of the robot is relative to the axial direction of the mother pipe. Then, a correction amount for making them parallel to each other is obtained, and the circumferential angle and vertical inclination of the mother pipe and the position (angle) in the horizontal plane are corrected according to the obtained correction amount. A method has also been proposed in the past (see, for example, Patent Document 2).

  By the way, when performing the welding operation of the main pipe and the branch pipe at the time of manufacturing the header, the applicant of the present application has made the entire circumference in the circumferential direction of the branch pipe even if it is a narrow part that is difficult to access with a normal welding torch. In order to be able to perform fillet welding while moving the welding torch over the time, an automatic welding apparatus as shown in FIGS. 8 and 9 has been proposed in the past.

  As shown in FIG. 8, this is an articulated robot provided so as to be movable in accordance with the mounting positions of a plurality of branch pipes 2 arranged in the longitudinal direction of the mother pipe 1 along the longitudinal direction of the mother pipe 1. A branch pipe welder (stub pipe welder) 4 is attached to the distal end side of 3.

  Further, as shown in FIG. 9, the branch pipe welder 4 includes a horseshoe-type guide 5 having a notch 5a that can be inserted and surrounded by the branch pipe 2 from the radial direction, and the branch pipe 2 from the radial direction. A notched ring gear 6 having a notch 6a that can be inserted and surrounded, and is supported on the lower side of the horseshoe guide 5 so as to be rotatable beyond the notch 5a of the horseshoe guide 5, and the horseshoe guide A drive mechanism 7 for rotating the ring gear 6 relative to the ring gear 5, a torch mounting member 8 having a notch 8a at the same position as the ring gear 6 fixed to the ring gear 6, and the torch mounting A torch support block 9 attached to the lower side of the member 8 via a slide guide 10 so as to be slidable in the radial direction, and attached to the torch support block 9 downward and with its lower end facing the center side of the ring gear 6. Attached melt It is constituted comprising a torch 11 Metropolitan.

  Thereby, in the branch pipe welding machine 4, the branch pipe is operated by the operation of the articulated robot 3 in a state where the phase of the cutout portion 6 a of the ring gear 6 is matched with the phase of the cutout portion 5 a of the horseshoe-type guide 5. The welder 4 is brought closer to the side of the branch pipe 2 that is temporarily fixed to the upper end side position of the outer peripheral surface of the mother pipe 1, and the horseshoe guide 5 and the ring gear 6 of the branch pipe welder 4 are notched. The parts 5a and 6a are externally fitted to the branch pipe 2, whereby the welding torch 11 attached to the ring gear 6 via the torch attachment member 8, the slide guide 10 and the torch support block 9 is The pipe 2 and the mother pipe 1 can be arranged toward one place in the circumferential direction of the welded place.

  Therefore, after that, when the ring gear 6 is driven by the drive mechanism 7, the welding torch 11 together with the ring gear 6 extends around the branch pipe 2 and exceeds the notch 5 a of the horseshoe-type guide 5. It is designed to be operated around.

  Therefore, it is possible to weld the branch pipe 2 disposed inside the horseshoe-type guide 5 and the mother pipe 1 therebelow by the welding torch 11 that moves around the entire circumference in the circumferential direction. It is.

  In the automatic welding apparatus shown in FIGS. 8 and 9, in order to increase the positioning accuracy of the welding torch 11 with respect to the welded portion between the branch pipe 2 and the mother pipe 1, It is necessary to adjust the shaft misalignment and inclination.

  Therefore, an optical sensor or a probe that opposes each other is attached to the tip of the notch 5a of the horseshoe guide 5 across the U-shaped opening so that the position of the branch pipe 2 and the horseshoe guide 5 It has been proposed to detect the relative inclination of the horseshoe guide 5 and adjust the arrangement of the horseshoe-shaped guide 5 according to the detected position and relative inclination of the branch pipe 2 (for example, Patent Documents). 3).

Japanese Patent No. 3385390 Japanese Examined Patent Publication No. 4-31748 JP 10-193112 A

  However, as shown in Patent Document 1, only the reference branch canal is detected by touch sensing, and the position of other branch pipes is calculated from the position data of the reference branch pipe. Errors due to deviation of individual branch pipes and distortion of the mother pipe are not considered.

  However, in practice, the mother pipe itself may be bent or distorted due to the influence of heat during the welding of the branch pipe, and the branch pipe mounting portion of the mother pipe communicates with the branch pipe. There is an error in the hole itself, but errors may occur depending on the accuracy of the hole itself. For branch pipes other than the reference branch pipe, it is possible that the welding torch cannot be accurately placed at the weld location with the main pipe. There is sex.

  As shown in Patent Document 2, the position of the branch pipe temporarily attached to the mother pipe is detected by touch sensing, and the position of the branch pipe is corrected by moving the mother pipe side according to the detection result. In the method, when the mother pipe becomes large, there arises a problem that a large positioning device for moving the mother pipe is required.

  In addition, an optical sensor or a probe is attached to the tip of the horseshoe type guide 5 of the branch pipe welder 4 in the automatic welding apparatus shown in Patent Document 3, and the position of the branch pipe 2 and the relative to the horseshoe type guide 5 are attached. The method of detecting a typical inclination can adjust the arrangement of the horseshoe-shaped guide 5 according to the detected position of the branch pipe 2 and the relative inclination. This is effective for accurately disposing the welding torch 11 of the branch pipe welding machine 4 at the welding point.

  By the way, in recent years, a header having a configuration in which the branch pipes 2 are densely arranged in the circumferential direction and the longitudinal direction of the mother pipe 1 may be required as a header. In this case, the header adjacent to the branch pipe 2 attached to the mother pipe 1 may be required. The distance between the objects to be performed becomes narrow. Therefore, when the horseshoe-type guide 5 is externally fitted to the branch pipe 2 to be welded, the two tip portions sandwiching the U-shaped opening of the notch 5a of the horseshoe-type guide 5 are to be welded. It is necessary to accurately insert into a narrow gap between the branch pipe 2 and the branch pipes 2 adjacent to both sides thereof.

  In this case, before the horseshoe guide 5 is externally fitted to the branch pipe 2 to be welded, the position of the branch pipe 2 to be welded and the relative inclination with respect to the horseshoe guide 5 can be detected. As will be desired, it is considered that it is difficult to detect the position of the branch pipe 2 before the horseshoe guide 5 is fitted with the optical sensor provided at the tip of the horseshoe guide 5.

  On the other hand, when a probe is provided at the tip of the horseshoe-type guide 5, it is possible to detect the position of the branch pipe 2 to be welded before the horseshoe-type guide 5 is externally fitted. When the attachment position of the branch pipe 2 in the circumferential direction of the mother pipe 1 is shifted in the longitudinal direction of the mother pipe 1, when fitting the horseshoe-shaped guide 5 to the branch pipe 2 to be welded, It is conceivable that the probe at the tip of the horseshoe-type guide 5 may interfere with another branch pipe 2 already attached to the mother pipe 1.

  Therefore, the present invention further develops the automatic welding apparatus shown in Patent Document 3 above, and even when the branch pipes are densely arranged in the circumferential direction and the longitudinal direction of the mother pipe, Before fitting the horseshoe guide to the branch pipe to be welded, the position of the branch pipe to be welded can be detected, and the horseshoe guide is accurately attached to the branch pipe to be welded. The branch pipe to be welded can be accurately placed in the center of the circumferential track of the welding torch that moves circumferentially of the branch pipe welder, and the welding torch becomes the welding target. It is an object of the present invention to provide a positioning method and apparatus for a welding torch in an automatic welding apparatus, which can be arranged so as to be movable along the entire circumference in the circumferential direction of a welded portion between a branch pipe and a mother pipe.

In order to solve the above-mentioned problems, the present invention is adapted to correspond to the first aspect, wherein the outer side of the branch pipe to be welded on the side surface in the direction perpendicular to the pivot axis of the swivel base provided at the tip of the robot hand of the robot is provided. a guide having a notch for causing fitted, is held in the guide, and a welding torch are also available circumference operation and beyond the notch, with respect to the attachment position of the branch pipe welder comprising comprise The branch pipe detection sensor provided so as to be within the range of 90 degrees or more and 270 degrees or less around the pivot axis of the swivel base is arranged toward the branch pipe to be welded temporarily attached to the mother pipe. by the branches tube detection sensor, the position in the longitudinal direction of the mother tube of the branch tube of the welding object, and detects the position of the horizontal direction perpendicular to the longitudinal direction of the mother tube of the branch tube of the welding object, then the by the turning of the swivel base, the branch pipe of the welded The digit above branch pipe welding machine guide, after placing on one side of the horizontal direction perpendicular to the longitudinal direction of the mother pipe to a branch pipe of the welded, the the branches tubing welder, in the longitudinal direction of the substrate tube When the guide is externally fitted to the branch pipe to be welded by moving along an orthogonal horizontal direction, the center of the track on which the branch pipe to be welded moves circumferentially of the welding torch of the branch pipe welder It is set as the positioning method of the welding torch in the automatic welding apparatus which makes the said branch pipe welder stop at the position arrange | positioned in this.

Further, in the above configuration, after the guide of the branch pipe welder is fitted over the branch pipe to be welded, the welding torch that moves circumferentially of the branch pipe welder is moved around the branch pipe to be welded. In addition, at a plurality of locations in the circumferential direction, using the welding torch wire as a probe, touch sensing is performed between the positions of the branch pipes to be welded and the mother pipe located below the welded pipe, and the touch by linking the location information obtained by sensing the circumferential direction, to obtain the detailed location information over the entire circumference in the circumferential direction of the welding points, based on the position information, the deviation amount of the welding torch by the robot To correct.

According to a third aspect of the present invention, there is provided a guide having a notch for externally fitting to a branch pipe to be welded by a robot, and being able to move circumferentially beyond the notch held by the guide. A swivel is provided at the tip of the robot robot's robot hand in an automatic welding apparatus capable of operating a branch pipe welder provided with a welding torch, and is provided on a side surface perpendicular to the swivel axis. , Rutotomoni attaching the branch pipe welder, with respect to the attachment position of the branch pipe welder, 90 degrees or more around the revolving stand of the pivot axis, to fit the range of 270 degrees, the main pipe have a tack has been attached to the branch pipe to be welded formed by providing a branch pipe detect sensor for detecting a horizontal position perpendicular to the longitudinal direction of the position and the substrate tube in the longitudinal direction of the mother tube configurations, further The above branch pipe welder When the guide is externally fitted to the branch pipe to be welded by moving in a horizontal direction perpendicular to the hand direction, the center of the track on which the branch pipe to be welded moves circumferentially of the welding torch of the branch pipe welder The welding torch positioning device in the automatic welding apparatus having a configuration including a robot controller capable of stopping the branch pipe welder at a position arranged at the position .

According to the present invention, the following excellent effects are exhibited.
(1) and the guide having a notch for externally fitted to the branch pipes to be welded in the direction of the side surface perpendicular to the swivel base of the pivot axis provided at the tip portion of the robot hand of the robot, is held in the guide, And a welding torch capable of circumferential operation beyond the notch , and a mounting position of a branch pipe welder comprising 90 degrees or more and 270 degrees about the pivot axis of the swivel base the branch pipe detection sensor provided to fit in the following ranges, and disposed toward the branch pipe to be welded, which is tacked to the main pipe by the branches tube detection sensor, the substrate tube of the branch tube of the welding object longitudinally about the position, and detects a horizontal position perpendicular to the longitudinal direction of the mother tube of the branch tube of the welding object, then the turning of the swivel base, the branches toward the branch pipe of the welded object Guide the pipe welder to the branch pipe to be welded After placing on one side of the horizontal direction perpendicular to the longitudinal direction of the substrate tube against the the branches tubing welder, it is moved along a horizontal direction perpendicular to the longitudinal direction of the mother tube, welded to the guide The branch pipe welder is stopped at a position where the branch pipe to be welded is arranged at the center of the trajectory of the welding torch of the branch pipe welder when the outer pipe is fitted over the branch pipe. A positioning method of a welding torch in an automatic welding apparatus, a guide having a notch for externally fitting to a branch pipe to be welded by a robot, and a circumferential movement beyond the notch held by the guide A rotating base is provided at the tip of the robot hand of the robot in the automatic welding apparatus that can operate a branch pipe welding machine provided with a welding torch, and the direction is perpendicular to the turning axis of the rotating base. On the side of The branch pipe welder fitted with a Rutotomoni, with respect to the attachment position of the branch pipe welder, 90 degrees or more around the revolving stand of the pivot axis, to fit the range of 270 degrees, the temporary mother tube for the branch pipe with weld object have a formed by providing a branch pipe detect sensor for detecting constituting the horizontal position perpendicular to the longitudinal direction of the longitudinal about the position and the main pipe of the main pipe, and further, When the branch pipe welder is moved in the horizontal direction perpendicular to the longitudinal direction of the mother pipe and the guide is fitted on the branch pipe to be welded, the branch pipe to be welded is welded to the branch pipe welder. Since it is a positioning device for a welding torch in an automatic welding apparatus having a configuration including a robot controller capable of stopping the above-mentioned branch pipe welding machine at a position arranged in the center of a trajectory that moves in a circumferential direction of the torch. Circumferential direction and length Even when the interval between adjacent branch pipes attached to the mother pipe is narrow, as in the case of manufacturing a header having a configuration in which branch pipes are closely arranged in the direction, the robot robot hand The guide of the branch pipe welder attached via the swivel base can be accurately externally fitted to the branch pipe to be welded among the plurality of branch pipes temporarily attached along the longitudinal direction of the mother pipe. it can.
(2) Further, when the guide is externally fitted to the branch pipe to be welded, there is a possibility that the guide interferes with the branch pipe to be welded and other branch pipes already installed or temporarily attached to the mother pipe. Can be resolved.

It is the schematic which shows one Embodiment of the positioning apparatus of the welding torch in the automatic welding apparatus of this invention. FIG. 1 shows a procedure for positioning a welding torch by the apparatus of FIG. 1. (A) shows a state in which the probe senses the longitudinal position of a branch pipe to be welded by the probe, and (b) shows a probe. It is a schematic diagram which each shows the state which performs the touch sensing of the left-right direction position of the branch pipe used as the welding object by a child. FIG. 2 shows the procedure following FIG. 2 (b) as a procedure for positioning the welding torch by the apparatus of FIG. 1, and the wire of the welding torch is fitted to the branch pipe in which the horseshoe-type guide of the branch pipe welder is externally fitted. It is a schematic diagram which shows the state which performs touch sensing by. FIG. 5 is a schematic diagram showing another example of a probe in the apparatus of FIG. 1 as another embodiment of the present invention. FIG. 6 is a schematic diagram showing a configuration including a distance sensor for detecting the longitudinal position of a branch pipe to be welded as an application example of the apparatus of FIG. 1 as still another embodiment of the present invention. It is a schematic diagram which shows the structure provided with the displacement sensor for detecting the front-back direction position and the left-right direction position of the branch pipe used as welding object as another form of implementation of this invention. As still another embodiment of the present invention, a displacement sensor for detecting the front-rear direction position and the left-right direction position of a branch pipe to be welded, and a displacement for sensing the position of the branch pipe fitted with a horseshoe-type guide It is a schematic diagram which shows the structure provided with the sensor. It is a schematic perspective view which shows the conventional automatic welding apparatus for the branch pipe welding. It is a top view which expands and shows the branch pipe welder in the automatic welding apparatus of FIG.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  1 to 3 show an embodiment of a welding torch positioning method and apparatus in an automatic welding apparatus according to the present invention, which is as follows.

  That is, FIG. 1 shows a positioning device for a welding torch in the automatic welding apparatus of the present invention. The robot hand 12 in an articulated robot provided so as to be movable along a longitudinal direction of the mother pipe 1 by a moving mechanism (not shown). A swivel 13 is provided at the tip so as to be turnable.

  As in the case of the branch pipe welder 4 in the automatic welding apparatus shown in FIGS. 8 and 9, a guide is provided at a required position on the side surface of the swivel base 13 located in a direction orthogonal to the swivel axis 13a of the swivel base 13. A branch pipe welder 4 including a horseshoe guide 5 and a welding torch 11 that can be moved circumferentially together with the ring gear 6 (see FIG. 9) while being held by the horseshoe guide 5 is attached. In FIG. 1, for convenience of illustration, the description of the configuration other than the tip of the robot hand 12 of the articulated robot and the components other than the horseshoe guide 5 and the welding torch 11 in the branch pipe welder 4 is omitted. It is. Further, an arc drawn by a one-dot chain line in the drawing shows an outline of the orbit of the circumferential operation of the welding torch 11 (the same applies to FIGS. 2 (A), (B) to FIG. 7 described later).

  Further, when the horseshoe-type guide 5 of the branch pipe welder 4 is externally fitted to the branch pipe 2 a to be welded temporarily attached to the mother pipe 1 from the lateral direction in the swivel base 13, The direction that does not interfere with the other existing or temporarily attached branch pipes 2, specifically, the direction of the attachment position of the branch pipe welder 4 around the turning axis 13 a of the swivel base 13 is set to 0 degree. As a branch pipe detection sensor, a required dimension extends outward along a direction orthogonal to the pivot axis 13a of the swivel base 13 on the side surface in the angle range of 90 degrees or more and 270 degrees or less in the circumferential direction. A linear probe 14 is attached via an attachment member 15. Thus, when the horseshoe guide 5 of the branch pipe welder 4 is externally fitted to the branch pipe 2a to be welded from the lateral direction, the probe 14 is perpendicular to the traveling direction of the horseshoe guide 5. When the welding operation is performed by fitting the horseshoe-shaped guide 5 of the branch pipe welder 4 to the branch pipe 2a to be welded, the probe 14 is not projected and arranged in front of the direction. Is prevented from interfering with other branch pipes 2 already installed or temporarily attached to the mother pipe 1.

  From the standpoint of facilitating the control of the swivel base 13 and the processing for detecting the position information of the location where the probe 14 contacts in the branch pipe 2a to be welded, which will be described later. Then, the mounting position of the probe 14 on the swivel base 13 is 90 degrees, 180 degrees, or 270 degrees in the circumferential direction around the swivel axis 13a with respect to the mounting position of the branch pipe welder 4. It is desirable to set to. In the figure, a configuration is shown in which the probe 14 is attached to the side surface in the direction of 180 degrees around the turning axis 13a with respect to the attachment position of the branch pipe welder 4 in the turning table 13.

  The probe 14 is connected to one electrode (positive electrode in the figure) 16a of an energization detection type touch sensor 16 via an energization line 17, and the other electrode (negative electrode in the figure) of the touch sensor 16. The other end of the energization line 18 having one end connected to 16 b is connected to the mother pipe 1. Furthermore, the robot for performing the control of the articulated robot (including the turning of the swivel base 13 and the control of the circumferential operation of the welding torch 11 in the branch pipe welder 4) using the contact detection signal by the touch sensor 16 as well. Input to the controller 19 is enabled. Thus, when the probe 14 comes into contact with the branch pipe 2a to be welded that is temporarily attached to the mother pipe 1, the touch sensor 16 can detect the contact between the two by energization. . Further, the robot controller 19 to which the contact detection signal is input, the position information of the tip of the robot hand 12 of the articulated robot controlled by the robot controller 19, and the position attached to the turntable 13. Based on the known data on the shape (length) of the probe 14 and the like, position information on the portion of the branch pipe 2a to be welded that is in contact with the probe 14 is, for example, the mother pipe 1 The X-axis direction that is the longitudinal direction of the X-axis, the Y-axis direction that is the horizontal direction perpendicular to the X-axis direction, and the Z-axis direction that is the vertical direction can be detected.

  Furthermore, it is good also as a structure which connected one electrode 16a of the said touch sensor 16 via the electricity supply line 21 to the wire 20 supplied to the welding torch 11 of the said branch pipe welding machine 4 as needed. With this configuration, as will be described later, the welding torch 11 is mounted in a state in which the horseshoe guide 5 of the branch pipe welder 4 is externally fitted to the branch pipe 2a to be welded that is temporarily attached to the mother pipe 1. Using the wire 20 as a probe, it is possible to detect contact with the branch pipe 2a to be welded and the mother pipe 1 located near the lower part thereof. Therefore, as in the case of the probe 14 described above, the robot controller 19 controls the position information of the tip of the robot hand 12 controlled by the robot controller 19 and the branches attached to the swivel base 13. Based on the information on the circumferential movement position of the welding torch 11 in the pipe welder 4 and the known data on the shape of the branch pipe welder 4 and the protruding amount of the wire 20, the branch pipe 2a to be welded and The position information of the place where the wire 20 of the welding torch 11 in the mother pipe 1 is in contact can be detected with respect to the coordinates in the XYZ triaxial directions.

  When positioning the welding torch by using the welding torch positioning device in the automatic welding apparatus of the present invention having the above-described configuration, first, the dimensions of the mother pipe 1, the dimensions of the branch pipe 2, The articulated robot is operated based on known data relating to the arrangement of the branch pipes 2 to be connected, for example, design data, and the swivel 13 at the tip of the robot hand 12 is temporarily attached to the mother pipe 1. Required from the main pipe 1 to one side in the Y-axis direction within a predetermined Z coordinate plane corresponding to the height position when the horseshoe-shaped guide 5 of the branch pipe welder 4 is fitted to the branch pipe 2a to be welded Place them apart. In this state, the probe 14 is arranged in parallel to the Y-axis direction toward the mother tube 1 by the turning operation of the turntable 13.

  Next, based on the design data regarding the connection point of the branch pipes 2 and 2a in the longitudinal direction (X-axis direction) of the mother pipe 1, the articulated robot is operated to change the probe 14 into FIG. As shown by a two-dot chain line in (a), it is inserted between the branch pipe 2a to be welded and another branch pipe 2 adjacent to one side in the X-axis direction. At this time, the positions of the branch pipes 2 and 2a arranged in the X-axis direction are not significantly changed from the design data. On the other hand, the probe 14 is linear and has a horizontal width dimension. Is significantly smaller than the arrangement interval of the branch pipes 2 and 2a in the X-axis direction, so that the probe 14 is placed on the branch pipe 2a to be welded or one of the X-axis direction thereof. There is no possibility of coming into contact with other adjacent branch pipes 2.

  Next, as indicated by an arrow a in FIG. 2 (a), the probe 14 is moved in the direction approaching the side surface of the branch pipe 2a to be welded by the operation of the articulated robot. With this movement, when the probe 14 contacts the side surface of the branch pipe 2a to be welded, as shown by a solid line in FIG. Detected. Therefore, in the robot controller 19 to which the contact detection signal is input, the place where the probe 14 contacts the branch pipe 2a to be welded, that is, the predetermined Z coordinate plane of the branch pipe 2a to be welded. The X coordinate for one end position in the X-axis direction is obtained. Therefore, the center position of the branch pipe 2a to be welded in the predetermined Z coordinate plane is determined from the X coordinate thus obtained and the radius dimension of the branch pipe 2a to be welded that is known from the design data. Since the X coordinate can be detected, the value is temporarily stored in the robot controller 19.

  When the X coordinate of the center position of the branch pipe 2a to be welded in the predetermined Z coordinate plane is found as described above, the robot controller 19 operates the articulated robot to move the probe 14 to the above-described position. Once pulled out from between the branch pipe 2a to be welded and the other branch pipe 2 adjacent to one of the X-axis direction in one of the Y-axis directions (the direction away from the branch pipe 2a to be welded), and then in the Y-axis direction The probe 14 arranged parallel to the X coordinate position is arranged at the same X coordinate position as the X coordinate of the center position of the branch pipe 2a to be welded in the predetermined Z coordinate plane.

  Next, the probe 14 is moved to the other side in the Y-axis direction (direction approaching the branch pipe 2a to be welded) by operation of the articulated robot. With this movement, when the tip of the probe 14 comes into contact with the outer peripheral surface of the branch pipe 2a to be welded as shown in FIG. 19, the robot controller 19 causes the branch pipe 2 a to be welded to be welded at the point where the probe 14 is in contact with the branch pipe 2 a to be welded, that is, within the predetermined Z coordinate plane. At least the Y coordinate of the portion of the outer peripheral surface of the outer peripheral surface that protrudes most in one direction in the Y-axis direction is detected, and from the value and the known radial dimension of the branch pipe 2a to be welded, The Y coordinate of the center position of the branch pipe 2a to be welded is detected and temporarily stored. Thereby, the XY coordinates of the center position of the branch pipe 2a to be welded in the predetermined Z coordinate plane become clear.

  When the detection of the XY coordinates of the center position of the branch pipe 2a to be welded in the predetermined Z coordinate plane is completed by touch sensing using the probe 14 as described above, the robot controller 19 After operating the robot to move the probe 14 away from the outer peripheral surface of the branch pipe 2a to be welded to one side in the Y-axis direction, the swivel 13 is swiveled 180 degrees to obtain FIG. As shown, the branch pipe welder 4 is arranged so that the notch 5a of the horseshoe-type guide 5 faces the branch pipe 2a to be welded along the Y-axis direction. Further, at this time, the X coordinate of the center position of the circumferential operation of the welding torch 11 in the branch pipe welder 4 is made coincident with the X coordinate of the center position of the branch pipe 2a to be welded that has been detected and stored. Like that.

  Thereafter, the robot controller 19 moves the branch pipe welder 4 to the other side in the Y-axis direction within the predetermined Z coordinate plane by the operation of the articulated robot, as shown in FIG. The horseshoe-shaped guide 5 of the pipe welder 4 is externally fitted to the branch pipe 2a to be welded, and the Y coordinate of the center position of the circumferential operation of the welding torch 11 in the branch pipe welder 4 is stored in the memory. It stops at a position that coincides with the Y coordinate of the center position of the branch pipe 2a to be welded. As a result, the branch pipe 2a to be welded can be accurately placed at the center of the orbit of the circumferential operation of the welding torch 11 of the branch pipe welder 4. When the horseshoe-shaped guide 5 of the branch pipe welder 4 is externally fitted to the branch pipe 2a to be welded, the circumferential operation of the welding torch 11 in the branch pipe welder 4 within the predetermined Z coordinate plane. The X-coordinate of the center position of the branch pipe and the X-coordinate of the center position of the branch pipe 2a to be welded that have been measured in advance are matched, and then the horseshoe guide 5 of the branch pipe welder 4 is moved to the other side in the Y-axis direction. Therefore, the horseshoe-type guide 5 of the branch pipe welder 4 may interfere with the branch pipe 2a to be welded or another branch pipe 2 that is already installed or temporarily attached to the mother pipe 1. There is no.

  When the horseshoe guide 5 of the branch pipe welder 4 is externally fitted to the branch pipe 2a to be welded as described above, the robot controller 19 attaches the welding torch 11 of the branch pipe welder 4 to the welding pipe. A circumferential operation is performed around the target branch pipe 2a, and at a plurality of positions in the circumferential direction, the wire 20 of the welding torch 11 is used as a probe and positioned at the lower end of the branch pipe 2a to be welded or in the vicinity thereof. From the position of the wire 20 of the welding torch 11 when contact is detected by the touch sensor 16 based on energization at each location so as to be in contact with the mother pipe 1 to be welded, the branch pipe 2a to be welded is determined. In addition, the coordinates of the XYZ three-axis directions are detected at the locations where the wires 20 of the welding torch 11 in the mother pipe 1 are in contact. Thereby, in the robot controller 19, the position information detected at a plurality of locations in the circumferential direction is linked to each other, so that the actual welding location between the branch pipe 2a to be welded and the mother pipe 1, that is, another branch pipe 2 is obtained. Deflection and distortion of the mother pipe 1 caused by heat at the time of welding, the accuracy of holes (not shown) provided in the attachment portions of the branch pipes 2 in the mother pipe 1, and the temporary attachment to the mother pipe 1 Detailed position information can be obtained over the entire circumference in the circumferential direction of an actual welding location including various errors caused by the inclination of the branch pipe 2a to be welded.

  Therefore, in the robot controller 19, teaching for correcting the displacement amount to the articulated robot based on the detailed position information obtained for the actual welding location between the branch pipe 2a to be welded and the main pipe 1 is performed. I do. As a result, the position of the welding torch 11 is moved to the position to be welded while the welding torch 11 is moved around the branch pipe 2a to be welded by the operation of the articulated robot that has been taught. Adjustment can be made in accordance with the actual welding location between the branch pipe 2a and the mother pipe 1. Therefore, with the welding torch 11, appropriate welding (fillet welding) can be performed over the entire circumference in the circumferential direction of the welded portion between the branch pipe 2a to be welded and the mother pipe 1.

  Therefore, when each branch pipe 2 is sequentially welded to the mother pipe 1 by sequentially repeating the same procedure as described above for each branch pipe 2 temporarily attached to the mother pipe 1, the individual branch pipes are used. 2 and the main pipe 1 located in the vicinity thereof can be detected individually, so that the welding torch 11 that moves in the circumference of the branch pipe welder 4 is detected for each branch pipe 2 individually. What is necessary is just to make it adjust a position corresponding to an actual welding location.

  Thus, according to the welding torch positioning method and apparatus in the automatic welding apparatus of the present invention, in order to manufacture a header having a configuration in which the branch pipes 2 are densely arranged in the circumferential direction and the longitudinal direction of the mother pipe 1, The horseshoe guide of the branch pipe welder 4 attached to the robot hand 12 of the articulated robot via the swivel 13 even when the interval between adjacent ones of the branch pipes 2 attached to the mother pipe 1 becomes narrow. 5 can be accurately fitted to the branch pipe 2a to be welded among the plurality of branch pipes 2 temporarily attached along the longitudinal direction of the mother pipe 1. Further, when the horseshoe guide 5 is externally fitted to the branch pipe 2a to be welded, the horseshoe guide 5 is attached to the branch pipe 2a to be welded or another branch pipe 2 that is already or temporarily attached to the mother pipe 1. The possibility of interfering with can be eliminated.

  In the above embodiment, the probe 14 is used in advance before the horseshoe-type guide 5 of the branch pipe welder 4 is externally fitted to the branch pipe 2a to be welded temporarily attached to the mother pipe 1. Based on the touch sensing, the XY coordinates in the predetermined Z coordinate plane are obtained for the center position of the branch pipe 2a to be welded. However, by moving the horseshoe guide 5 along the Y-axis direction, the two tip portions sandwiching the U-shaped opening of the notch 5a (see FIG. 9) of the horseshoe guide 5 are connected to the branches to be welded. The operation itself of accurately inserting into the gap between the pipe 2 and the branch pipes 2 adjacent to both sides thereof is performed within the predetermined Z coordinate plane of the branch pipe 2a to be welded temporarily attached to the mother pipe 1. If only the X coordinate is known, it can be implemented.

  In view of this point, as shown in FIG. 4, a heat-resistant optical or magnetic material is disposed on the upper side of the rear end portion of the notch 5 a (see FIG. 9) of the horseshoe-type guide 5 of the branch pipe welder 4. It is good also as a structure which provides the displacement sensor 22 of a type | formula.

  Other configurations are the same as those shown in FIGS. 1 to 3, and the same components are denoted by the same reference numerals.

  In the case of such a configuration, the probe 14 detects the X coordinate in the predetermined Z coordinate plane with respect to the center position of the branch pipe 2a to be welded similar to that shown in FIG. Only the touch sensing is performed, and then the branch pipe welder 4 is operated in the circumferential direction of the welding torch 11 based on the detected X coordinate in the predetermined Z coordinate plane of the branch pipe 2a to be welded. The notch portion 5a of the horseshoe guide 5 extends along the Y-axis direction in a state in which the X coordinate of the center position of the horseshoe guide 5 matches the X coordinate of the center position of the branch pipe 2a to be welded that has been detected and stored It arrange | positions so that the said branch pipe 2a to be welded may be faced, Then, the said branch pipe welder 4 is moved along the Y-axis direction, and the horseshoe-shaped guide 5 is externally fitted to the said branch pipe 2a to be welded. Then, the proximity of the branch pipe 2a to be welded is the horseshoe type The center position of the circumferential operation of the welding torch 11 in the branch pipe welder 4 because it is detected by the displacement sensor 22 provided at the back end of the notch 5a (see FIG. 9). If the Y-coordinate of the branch pipe welder 4 is stopped at the time when the Y coordinate of the branch pipe welder 4 coincides with the center position of the branch pipe 2a to be welded detected by the displacement sensor 22, the welding is performed. The target branch pipe 2a can be accurately arranged at the center of the circumferential motion track of the welding torch 11 of the branch pipe welder 4.

  Therefore, even with this configuration, it is possible to obtain the same effects as those of the embodiment shown in FIGS.

  Next, FIG. 5 shows a modification of the probe 14 in the embodiment of FIGS. 1 to 3 as another embodiment of the present invention.

  That is, in the present embodiment, the probe is required in a direction perpendicular to the straight line portion 23 extending in a required direction outward along a direction orthogonal to the pivot axis 13 a of the swivel base 13 and from the tip of the straight line portion 23. It is assumed that the probe 14a has a configuration including a bending portion 24 extending in size.

  Other configurations are the same as those shown in FIGS. 1 to 3, and the same components are denoted by the same reference numerals.

  When using the welding torch positioning device in the automatic welding device of the present embodiment having the above-described configuration, the probe 14a is temporarily attached to the mother pipe 1 in the same manner as shown in FIG. When inserting between the branch pipe 2a to be welded and the other branch pipe 2 adjacent to one side in the X-axis direction and when pulling out between the branch pipes 2a and 2, the articulated robot If the bent portion 24 of the probe 14 is arranged in the vertical direction by the above operation, the bent portion 24 is the branch pipe 2a to be welded or another branch pipe adjacent to one of the X-axis direction. In the state in which the possibility of interference with the tube 2 is prevented, touch sensing of one end position in the X-axis direction of the branch pipe 2a to be welded is performed in the same manner as the probe 14 in the embodiment of FIGS. Can be implemented.

  Further, by arranging the bent portion 24 of the probe 14a to be horizontal, the Y-axis direction of the outer peripheral surface of the branch pipe 2a to be welded similar to that shown in FIG. Touch sensing for the most protruding part in one direction can be more easily performed by the bent portion 24 of the probe 14a extending in a required dimension in the horizontal direction.

  Next, FIG. 6 shows still another embodiment of the present invention. In the same configuration as the embodiment of FIGS. 1 to 3, the branch pipe detection sensor is replaced with the probe 14 and the heat resistant type is used. The optical or magnetic displacement sensors 25 and 26 are configured as follows.

  That is, in the same configuration as in FIGS. 1 to 3, the swivel base 13 has a side surface in a direction of 180 degrees around the swivel axis 13 a with respect to the mounting position of the branch pipe welder 4 in the swivel base 13. A linear sensor support rod 27 is provided extending a required dimension outward along a direction orthogonal to the pivot axis 13a. The sensor support rod 27 is provided with a sensor support branch rod 28 that extends a required dimension from the midway position to one side in the perpendicular direction.

  Furthermore, a pair of optical or magnetic displacement sensors 25 are provided opposite to each other near one end of the tip of the sensor support rod 27 and the end of the sensor support branch rod 28 near the sensor support rod 27. . Thereby, the branch pipe 2a to be welded is relatively close to one side of the sensor support rod 27, and the end portion on the side close to the sensor support rod 27 in the circumferential direction of the branch pipe 2a to be welded is When entering between the opposed displacement sensors 25, the displacement sensor 25 can detect the presence of the branch pipe 2a to be welded.

  Further, the side surface of the sensor support branch rod 28 in the direction away from the swivel base 13 and the corresponding portion of the sensor support rod 27 closer to the tip than the mounting position of the sensor support branch rod 28 are optical or magnetic. A pair of displacement sensors 26 are provided so as to face each other. As a result, the branch pipe 2a to be welded is relatively close to the sensor support branch rod 28 from the direction away from the swivel base 13, and the sensor support branch in the circumferential direction of the branch pipe 2a to be welded. When the end close to the rod 28 enters between the displacement sensors 26 arranged to face each other, the displacement sensor 26 can detect the presence of the branch pipe 2a to be welded.

  Further, although not shown, the detection signals of the branch pipes 2a to be welded by the sensors 25 and 26 are both transmitted to the robot controller 19 similar to the robot controller 19 of the embodiment shown in FIGS. Position information of the tip of the robot hand 12 of the articulated robot controlled by the robot controller 19 at the time when the branch pipe 2a to be welded is detected by the sensors 25 and 26, Based on the known data about the arrangement and the like of the displacement sensors 25 and 26 attached to the swivel base 13 via the sensor support rod 27 and the sensor support branch rod 28, the above-mentioned each of the branch pipes 2 a to be welded is described above. For example, the position information about the points detected by the displacement sensors 25 and 26 is the X-axis direction which is the longitudinal direction of the mother pipe 1; The Y-axis direction is a horizontal direction perpendicular to the record, are to be detected with respect to the coordinates of the Z-axis direction is a vertical direction.

  Other configurations are the same as those shown in FIGS. 1 to 3, and the same components are denoted by the same reference numerals.

  When using the welding torch positioning device in the automatic welding apparatus of the present embodiment having the above-described configuration, the sensor support rod 27 is made parallel to the Y-axis direction by the turning operation of the turntable 13, and the sensor support. Based on the design data on the mounting position of the branch pipe 2 in which the sensor support rod 27 is arranged in the longitudinal direction of the mother pipe 1 in a predetermined Z-axis plane in a state where the branch rod 28 is arranged parallel to the X-axis direction. Then, it inserts between the branch pipe 2a of the welding object temporarily attached to the mother pipe 1, and the other branch pipe 2 adjacent to one side in the X-axis direction. At this time, the positions of the branch pipes 2 and 2a arranged in the X-axis direction are not significantly changed from the design data. On the other hand, the sensor support rod 27 is linear and has a horizontal width. Since the dimension is made smaller than the arrangement interval of the branch pipes 2 and 2a in the X-axis direction, the sensor support rod 27 is adjacent to the branch pipe 2a to be welded or one of the X-axis directions. There is no risk of contacting other branch pipes 2.

  Next, when the sensor support rod 27 is moved to the other side in the X-axis direction by the operation of the articulated robot, the displacement sensor 25 causes the X-axis direction in the predetermined Z coordinate plane of the branch pipe 2a to be welded. Therefore, the robot controller 19 obtains the X coordinate for the detected position, and the welding target branch that is known from the obtained X coordinate and the design data. From the dimension of the radius of the pipe 2a, the X coordinate of the center position of the branch pipe 2a to be welded in the predetermined Z coordinate plane can be detected.

  Further, when the sensor-supporting branch rod 28 is moved along the Y-axis direction in the direction close to the branch pipe 2a to be welded by the operation of the articulated robot, the displacement sensor 26 causes the predetermined Z coordinate to move. In the plane, the most projecting portion in the Y-axis direction on the outer peripheral surface of the branch pipe 2a to be welded is detected, and the robot controller 19 obtains the Y coordinate for the detected position. From the obtained Y coordinate and the radius dimension of the branch pipe 2a to be welded known from the design data, the Y coordinate of the center position of the branch pipe 2a to be welded in the predetermined Z coordinate plane is obtained. Can be detected.

  As described above, the XY coordinates of the center position of the branch pipe 2a to be welded in the predetermined Z coordinate plane are clarified. Thereafter, based on the obtained XY coordinates of the center position of the branch pipe 2a to be welded. In the same manner as shown in FIGS. 1 to 3, the branch pipe welding machine 4 is positioned with respect to the branch pipe 2a to be welded, so that the same effect as that of the embodiment of FIGS. Can be obtained.

  Note that the present invention is not limited to the above embodiment, and the wire 20 of the welding torch 11 is fitted after the horseshoe-type guide 5 of the branch pipe welder 4 is externally fitted to the branch pipe 2a to be welded. Although it is shown that the detailed position information is obtained over the entire circumference in the circumferential direction with respect to the welded portion between the branch pipe 2a to be welded and the mother pipe 1 in the vicinity thereof by touch sensing using As shown in FIG. 7, a heat-resistant optical or magnetic displacement sensor 29 is provided corresponding to a plurality of locations in the circumferential direction of the circumferential motion of the welding torch 11 in the horseshoe-type guide 5. These displacement sensors 29 are used to describe the details of the circumferential multiple points related to the welded portion of the branch pipe 2a to be welded with the horseshoe-type guide 5 of the branch pipe welder 4 and the mother pipe 1 in the vicinity thereof. So as to obtain accurate location information Good. Also in this case, the robot controller 19 links the position information detected at a plurality of locations in the circumferential direction with each other, so that other branch pipes can be obtained at the actual welding location between the branch pipe 2a to be welded and the mother pipe 1. 2 of the mother pipe 1 caused by heat at the time of welding, the accuracy of the holes (not shown) provided in the attachment portions of the branch pipes 2 in the mother pipe 1, and the temporary attachment to the mother pipe 1 Detailed position information can be obtained over the entire circumference in the circumferential direction in a state including various errors due to the inclination of the branch pipe 2a to be welded.

  Further, after the horseshoe-type guide 5 of the branch pipe welder 4 is externally fitted, by the touch sensing using the wire 20 of the welding torch 11, the above-described branch pipe 2a to be welded and the mother pipe 1 in the vicinity thereof are connected. Regarding the welding location, it is assumed that detailed position information is obtained in advance over the entire circumference in the circumferential direction, and based on the position information, the articulated robot performs teaching to correct the amount of deviation and then performs welding. Although shown, welding may be performed while correcting the shift amount.

  After the horseshoe-shaped guide 5 of the branch pipe welder 4 is externally fitted to the branch pipe 2a to be welded, the circumferential direction of the welded portion between the branch pipe 2a to be welded and the mother pipe 1 in the vicinity below the welded pipe 2a. It is desirable to obtain detailed positional information over the entire circumference, but when the bending or distortion of the mother pipe 1 due to heat during welding is small, or in the hole (not shown) provided in the attachment portion of each branch pipe 2 in the mother pipe 1 If the accuracy is sufficiently high, etc., after fitting the horseshoe-shaped guide 5 of the branch pipe welder 4, the touch on the welded portion between the branch pipe 2a to be welded and the mother pipe 1 in the vicinity thereof is touched. Sensing may be omitted. In this case, the structure which connects the wire 20 supplied to the welding torch 11 to the touch sensor 16 through the energization line 21 can be omitted.

  The branch pipe detection sensor can detect at least the position of the branch pipe 2a to be welded temporarily attached to the mother pipe 1 in the X-axis direction, and the branch pipe 2a to be welded temporarily attached to the mother pipe 1 The horizontal width dimension of the portion inserted between the other branch pipes 2 adjacent to the X-axis between the branch pipe 2a to be welded temporarily attached to the mother pipe 1 and the other branch pipe 2 adjacent thereto It is designed to be sufficiently smaller or smaller than the arrangement interval in the direction, and further when the horseshoe guide 5 of the branch pipe welder 4 is externally fitted to the branch pipe 2a to be welded from the lateral direction. As long as it can be attached to the swivel base 13 so that it does not protrude forward from the direction perpendicular to the traveling direction of the horseshoe-type guide 5, it may have a shape other than that shown in the figure, and the probe 14 or the displacement sensor 25. Adopting any detection method other than 26 Good.

  The attachment position of the branch pipe detection sensor on the swivel base 13 is from the viewpoint of facilitating the control of the swivel base 13 and the processing for detecting the position information of the branch pipe 2a to be welded. It is desirable to set the direction of 90 degrees, 180 degrees, or 270 degrees in the circumferential direction around the pivot axis 13a with respect to the mounting position of the branch pipe welder 4 on the swivel base 13. If the horseshoe guide 5 of the welding machine 4 does not protrude forward from the direction perpendicular to the traveling direction of the horseshoe guide 5 when the horseshoe guide 5 is externally fitted to the branch pipe 2a to be welded, You may change the attachment position of the said branch pipe detection sensor in the turntable 13 freely. Even in this case, when the horseshoe-type guide 5 of the branch pipe welder 4 is externally fitted to the branch pipe 2a to be welded and the welding operation is performed, the branch pipe detection sensor is already installed in the mother pipe 1. Or the effect that the possibility of interfering with the other branch pipe 2 temporarily attached can be eliminated.

  Of course, various modifications can be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Mother pipe 2a Branch pipe to be welded 4 Branch pipe welder 5 Horseshoe type guide (guide)
5a Notch 11 Welding torch 12 Robot hand 13 Swivel base 13a Swivel axis 14, 14a Probe (branch tube detection sensor)
20 wire 22 displacement sensor 25 displacement sensor (branch tube detection sensor)
26 Displacement sensor (branch pipe detection sensor)

Claims (3)

A guide having a notch for externally fitted to the branch pipes to be welded in the direction of the side surface perpendicular to the swivel base of the pivot axis provided at the tip portion of the robot hand of the robot, is held in the guide, and the notch a welding torch are also available circumferential operate beyond parts, with respect to the attachment position of the branch pipe welder comprising comprise more than 90 degrees about the swivel base of the swivel axis, 270 degrees or less in the range the branch pipe detection sensor provided to fit in, and disposed toward the branch pipe to be welded, which is tacked to the main pipe by the branches tube detection sensor, the longitudinal direction of the mother tube of the branch tube of the welding object relating to the position, and detects a horizontal position perpendicular to the longitudinal direction of the mother tube of the branch tube of the welding object, then the turning of the swivel base, the branch pipe welder towards branch pipe of the welded to guide the lateral pipe of the welded After placement in the horizontal direction of one side orthogonal to the longitudinal direction of the mother tube, the the branches tubing welder, is moved along a horizontal direction perpendicular to the longitudinal direction of the mother tube, the branches the guide of the welded The branch pipe welder is stopped at a position where the branch pipe to be welded is arranged at the center of the trajectory of the welding torch of the branch pipe welder when the pipe is fitted over the pipe. A positioning method of a welding torch in an automatic welding apparatus characterized by the above. After the guide of the branch pipe welder is externally fitted to the branch pipe to be welded, the circumferentially moving welding torch of the branch pipe welder is moved around the branch pipe to be welded and a plurality of circumferential torches in places, a ultrasonic probe wires of the welding torch carried out and the position of the branch pipe of the welded, the touch sensing welds between the base pipe positioned below the vicinity, the position obtained by the touch sensing by linking information in the circumferential direction, to obtain the detailed location information over the entire circumference in the circumferential direction of the welding points, based on the positional information, so as to correct the deviation amount of the welding torch by the robot The positioning method of the welding torch in the automatic welding apparatus of Claim 1. Branch pipe welding comprising: a guide having a notch for externally fitting to a branch pipe to be welded by a robot; and a welding torch that is held by the guide and is capable of moving circumferentially beyond the notch. machine provided with a swivel base to the tip of the robot hand of the robot in the automatic welding apparatus and are to manipulate, to the side of the direction perpendicular to the revolving stand swivel axis, Rutotomoni attaching the branch pipe welder , the mounting positions of the branch pipe welder, 90 degrees or more around the revolving stand of the pivot axis, to fit the range of 270 degrees, with the branch pipe to be welded, which is tacked to the main pipe Te have a formed by providing a branch pipe detect sensor for detecting constituting the horizontal position to the position and perpendicular to the longitudinal direction of the substrate tube in the longitudinal direction of the substrate tube, further, the branch pipe welder mother tube Horizontal direction perpendicular to the longitudinal direction When the guide is externally fitted to the branch pipe to be welded, the branch pipe to be welded is located at the center of the orbit where the welding torch of the branch pipe welder moves circumferentially. An apparatus for positioning a welding torch in an automatic welding apparatus, comprising a robot controller capable of stopping the branch pipe welder .

Images