Welding system, control device, and welding method

A welding system configured to weld a workpiece by using a welding device and a positioner includes a control device configured to control the welding device and the positioner. The positioner includes a workpiece position setting mechanism having reference position information, and at least one holding mechanism configured to hold the workpiece. The control device includes a positioner position calculation means for calculating a position of the holding mechanism when holding the workpiece based on the reference position information provided from the workpiece position setting mechanism and workpiece information inputted into the control device in advance.

TECHNICAL FIELD

The present invention relates to a welding system, a control device, and a welding method, and more specifically, to a welding system, a control device, and a welding method capable of automatically welding a large welding workpiece with a welding robot.

BACKGROUND ART

A welding device for automatically welding a large welding workpiece such as a steel frame structure with a welding robot has been disclosed so far. For example, a welding device disclosed in Patent Literature 1 includes a welding robot, a welding control device configured to control the welding robot, and a rotation positioner configured to hold a workpiece, and automatically generates an operating locus and a welding condition of the welding robot according to a welding robot locus and a welding condition prepared in advance, based on workpiece information such as a size of a steel frame structure and a shape of a welding joint inputted into an input means of the welding control device.

CITATION LIST

Patent Literature

SUMMARY OF INVENTION

Technical Problem

For welding the workpiece, a work for positioning a workpiece and a positioner configured to hold the workpiece to appropriate positions is required. The work for positioning the positioner requires a very time-consuming and troublesome work, and is performed by trial and error based on years of experience of a worker, which is not efficient.

Note that, the welding device disclosed in Patent Literature 1 is to automate the welding work after determining positions of the workpiece and the rotation positioner, and does not particularly consider the work for positioning the rotation positioner.

The present invention has been made in view of the above situations, and an object thereof is to provide a welding system, a control device, and a welding method capable of automatically calculating a position of a positioner at a time when holding a workpiece and improving work efficiency by automating a work for positioning the positioner.

Solution to Problem

The object of the present invention is achieved by a configuration of a following (1) relating to a welding system.

(1) A welding system configured to weld a workpiece by using a welding device and a positioner, the welding system including:a control device configured to control the welding device and the positioner,wherein the positioner includes a workpiece position setting mechanism having reference position information, and at least one holding mechanism configured to hold the workpiece, andwherein the control device includes a positioner position calculation means for calculating a position of the holding mechanism when holding the workpiece based on the reference position information provided from the workpiece position setting mechanism and workpiece information inputted into the control device in advance.

The preferred embodiments of the present invention relating to the welding system relate to following (2) to (8).

(2) The welding system according to the above (1), wherein the control device has a database in which the position of the holding mechanism at a time when holding the workpiece is stored for each of the workpiece information, andwherein the positioner position calculation means calculates the position of the holding mechanism at a time when holding the workpiece by referring to the database.

(3) The welding system according to the above (1) or (2), wherein the workpiece information includes at least one data of welding position data and size data of the workpiece.

(4) The welding system according to one of the above (1) to (3), wherein the control device includes a synchronous control unit configured to perform control such that an operation of the welding device and an operation of the positioner are synchronized with each other.

(5) The welding system according to one of the above (1) to (4), wherein the welding device is a welding robot, andwherein the welding robot and the positioner each have a moving shaft that can move in parallel.

(6) The welding system according to the above (5), wherein the positioner has two or more holding mechanisms,wherein when one of the holding mechanisms is set as a drive-side holding mechanism and other of the holding mechanisms is set as a driven-side holding mechanism, each of the drive-side holding mechanism and the driven-side holding mechanism has a servo motor for positioning to a predetermined position, andwherein the control device is configured to control a position of the driven-side holding mechanism based on a position positioned in the drive-side holding mechanism, with respect to the position of the holding mechanism at a time when holding the workpiece calculated by the positioner position calculation means.

(7) The welding system according to one of the above (1) to (6), wherein the control device has a program automatic generation means for automatically generating an operating program for moving the holding mechanism and the welding device to the position of the holding mechanism at a time when holding the workpiece calculated by the positioner position calculation means.

(8) The welding system according to one of the above (1) to (7), wherein the workpiece information includes gravity center data of the workpiece, andwherein the positioner position calculation means calculates the position of the holding mechanism at a time when holding the workpiece by referring to the gravity center data.

The object of the present invention is achieved by a configuration of a following (9) relating to a control device of a welding system.

(9) A control device of a welding system configured to weld a workpiece by using a welding device and a positioner,wherein the control device is to control the welding device and the positioner, andwherein the control device includes a positioner position calculation means for calculating a position of a holding mechanism of the positioner at a time when holding the workpiece based on reference position information provided from a workpiece position setting mechanism of the positioner and workpiece information inputted into the control device in advance.

The object of the present invention is achieved by a configuration of a following (10) relating to a control program of a welding system.

(10) A control program of a welding system configured to weld a workpiece by using a welding device and a positioner,wherein the control program is to control the welding device and the positioner, andwherein the control program includes a positioner position calculation step of calculating a position of a holding mechanism of the positioner at a time when holding the workpiece based on reference position information provided from a workpiece position setting mechanism of the positioner and workpiece information inputted into the control program in advance.

The object of the present invention is achieved by a configuration of a following (11) relating to a welding method.

(11) A welding method of welding a workpiece by using a welding device and a positioner, the welding method including:a process of controlling the welding device and the positioner by a control device configured to control the welding device and the positioner,wherein the positioner includes a workpiece position setting mechanism having reference position information, and at least one holding mechanism configured to hold the workpiece, andwherein the welding method includes a process of calculating a position of the holding mechanism at a time when holding the workpiece based on the reference position information provided from the workpiece position setting mechanism and workpiece information inputted into the control device in advance.

Advantageous Effects of Invention

According to the welding system, the control device, and the welding method of the present invention, it is possible to automatically calculate the position of the positioner at a time when holding the workpiece, and to improve work efficiency by automating the work for positioning the positioner.

DESCRIPTION OF EMBODIMENTS

A welding system according to an embodiment of the present invention will be described with reference toFIGS.1to4.

A welding system1is to weld a steel frame structure W, which is a workpiece for welding, by gas shielded arc welding, for example.

As shown inFIG.1, the welding system1includes a carriage20for a welding device and a control device, a welding robot30that is a welding device, a positioner40for holding the steel frame structure W in a predetermined position, and a control device50configured to control the welding robot30and the positioner40.

Referring toFIG.4, the welding robot30includes a slider mechanism22configured to move the mounted welding robot30toward or away from the steel frame structure W, and a manipulator32with 6-axis joints.

The positioner40includes a pair of rotation positioners10, which are holding mechanisms for the steel frame structure W, and a workpiece position setting mechanism41.

The control device50includes a PC (Personal Computer)51configured to control an entire operation of the welding system1, a positioner control unit52, and a welding robot control unit53. The PC51also has a database DB in which optimal positions of the holding mechanisms10at a time when holding the workpiece W are stored for each of workpiece information such as size data, welding position data or gravity center data and the like of the steel frame structure W, which will be described later.

As described above, the positioner40includes the pair of rotation positioners10, which are holding mechanisms for the steel frame structure W, and the workpiece position setting mechanism41.

The rotation positioners10are to hold and rotate the steel frame structure W during welding. As shown inFIG.1, the rotation positioners10of the present embodiment are constituted by a pair of a drive-side rotation positioner10A that is a drive-side holding mechanism and a driven-side rotation positioner10B that is a driven-side holding mechanism, and are configured to hold the pillar-shaped steel frame structure W in at least two points in a length direction of the steel frame structure W.

When welding a linear part of the steel frame structure W by the welding robot30, the rotation positioners10do not rotate the steel frame structure W, and when welding an arc part of the steel frame structure W by the welding robot30, the rotation positioners10rotate the steel frame structure W. Thereby, the welding system1can continuously weld not only the linear part but also the arc part of the steel frame structure W without cutting arc. As shown inFIG.1, the rotation positioner10of the present embodiment includes an annular holder11, an elevating arm mechanism12, a bracket13, and a carriage14for a rotation positioner. Note that, the arc part of the steel frame structure W is formed at a corner part.

The annular holder11is to accommodate and hold therein the steel frame structure W. As shown inFIG.1, a plurality of fixing jigs16for holding the steel frame structure W from all around is provided to be expandable and contractible on an inner side of the annular holder11. The annular holder11is configured to clamp and fix the steel frame structure W from all around by the plurality of fixing jigs16. As shown inFIG.2A, a gear11ais formed on an outer periphery of the annular holder11, and the gear11ais configured to mesh with a pinion gear (not shown) provided in the bracket13. Note that, the gear11ais not shown inFIG.1.

The elevating arm mechanism12is to divide and open and close the annular holder11. As shown inFIG.2A, the elevating arm mechanism12is provided on a side of the annular holder11and the bracket13, and one end-side is connected to an upper part of the annular holder11and the other end-side is connected to a side surface of the bracket13.

As shown inFIG.2A, the elevating arm mechanism12is, specifically, configured to divide and open the annular holder11in a predetermined position, and to rotate an arc part11b, which is a part of the annular holder11, in a clockwise direction to space the arc part from the other part of the annular holder11, thereby forming a state in which the steel frame structure W can be accommodated. After the steel frame structure W is accommodated as shown inFIG.2B, the elevating arm mechanism12is configured to rotate the arc part11bin a counterclockwise direction to again close the arc part11b, and to clamp and hold the steel frame structure W by the four fixing jigs16provided on the inner side of the annular holder11.

The bracket13is to accommodate the annular holder11. As shown inFIG.2A, the bracket13has such a shape of accommodating a lower half of the annular holder11and exposing an upper half of the annular holder11. In the bracket13, a pinion gear (not shown) arranged to mesh with the gear11aof the annular holder11and a drive unit M configured to drive the pinion gear are provided. Note that, the drive unit M may be provided for at least one of the pair of rotation positioners10, so that the other rotation positioner10is driven by rotation of one rotation positioner10. A reference sign10A inFIG.1indicates a drive-side rotation positioner, and a reference sign10B indicates a driven-side rotation positioner.

The carriages14for a rotation positioner are to cause each of the rotation positioners10to be movable along moving rails R1for a positioner. As shown inFIG.1, the carriages14for a rotation positioner are provided at a lower part of each of the rotation positioners10by a pair, and are configured to cause the rotation positioners10to be independently movable in the length direction of the steel frame structure W by a servo motor (not shown).

Note that, as described above, the rotation positioners10are each configured so that the gear11aformed on the outer periphery of the annular holder11and the pinion gear provided in the bracket13mesh with each other. Therefore, the rotation positioner10can rotate the annular holder11by the drive of the drive unit M, thereby rotating the steel frame structure W during welding work.

As shown inFIG.1, the workpiece position setting mechanism41is arranged on a carriage43for a workpiece position setting mechanism capable of moving in the length direction of the steel frame structure W along the moving rails R1for a positioner. Also, as shown inFIGS.1and3, a side surface of the workpiece position setting mechanism41is provided with a reference surface42for setting a reference position S in the length direction of the steel frame structure W by bringing one end of the steel frame structure W into contact with the reference surface, for example. Specifically, as described later, the workpiece position setting mechanism41has reference position information of the steel frame structure W, which is used so as to calculate optimal positions of the holding mechanisms10at a time when holding the workpiece W.

Note that, it is not necessarily required to bring one end of the steel frame structure W into contact with the reference surface42when setting the reference position S in the length direction of the steel frame structure W. For example, a slight gap may be provided between the reference surface42and one end of the steel frame structure W. In this case, the gap is preferably smaller than 10 mm.

In addition, the reference surface42is not required to be the side surface of the workpiece position setting mechanism41, i.e., a physical wall surface, like the present embodiment, as along as the reference position S in the length direction of the steel frame structure W can be set. For example, it is also possible to set the reference position S in the length direction of the steel frame structure W by using a non-contact means such as a laser sensor.

[1-2. Carriage for Welding Device and Control Device]

The carriage20for a welding device and a control device is to place thereon a welding mechanism that constitutes the welding system1. As shown inFIG.1, the carriage20for a welding device and a control device has a flat plate shape. A lower part of the carriage20for a welding device and a control device is provided with wheels21, and the carriage20for a welding device and a control device is configured to be movable along moving rails R2for a welding device and a control device by the wheels21that are driven by a motor (not shown). Specifically, the carriage20for a welding device and a control device is provided to be movable in parallel to the moving direction of the rotation positioners10as the length direction of the steel frame structure W.

A slider mechanism22that is driven by the motor (not shown) is provided at an upper part of the carriage20for a welding device and a control device, and the welding robot30and the control device50are placed on an upper part of the slider mechanism22. The slider mechanism22is configured to be movable in a direction orthogonal to the moving direction of the rotation positioners10, i.e., the length direction of the steel frame structure W, on the carriage20for a welding device and a control device. Therefore, the welding robot30placed on the upper part of the slider mechanism22is configured to be movable in the direction orthogonal to the moving direction of the rotation positioners10during welding. Note that, a wire supply receptacle configured to accommodate a welding wire that is supplied to a welding torch31(which will be described later), a nozzle exchange device configured to exchange a nozzle provided at a distal end of the welding torch31, a nozzle cleaning device configured to clean the nozzle, a wire cutting device configured to cut the welding wire, a slag removing device configured to remove slag that is generated at a welding part, and the like, which are all not shown, may be placed on the upper part of the slider mechanism22.

The welding robot30is to weld the steel frame structure W. As shown inFIG.1, the welding robot30includes a welding torch31configured to supply a welding wire to a distal end portion of the manipulator32. The welding torch31is connected to a welding power source (not shown), and power is supplied to the welding wire via the welding torch31.

The welding robot30is placed on the carriage20for a welding device and a control device via the slider mechanism22, and as described above, is provided to be movable in the moving direction of the rotation positioners10and in the direction orthogonal to the moving direction of the rotation positioners10. Note that, inFIG.1, the welding robot30is arranged between the pair of rotation positioners10, and is configured to weld a weld joint between the pair of rotation positioners10. The moving direction of the rotation positioners10also corresponds to the length direction of the steel frame structure W, and the direction orthogonal to the moving direction of the rotation positioners10corresponds to a width direction of the steel frame structure W.

The control device50is to control operations of the rotation positioners10, the carriages14for a rotation positioner, the carriage20for a welding device and a control device, the slider mechanism22, the welding robot30, the carriage43for a workpiece position setting mechanism, and the like.

Here, as shown inFIG.4, the control device50includes a PC51configured to control an entire operation of the welding system1, a positioner control unit52configured to control an operation of the positioner40, and a welding robot control unit53configured to control a welding operation of the welding robot30.

The PC51has a positioner position calculation means51a, a program automatic generation means51b, and a database DB in which optimal positions of the rotation positioners10at a time when holding the steel frame structure W are stored for each of workpiece information such as size data, welding position data or gravity center data and the like of the steel frame structure W.

Note that, as used herein, the database is a collection of information and the like stored in which predetermined distances should be maintained so as to prevent interference between the welding robot30and the rotation positioners10when welding the steel frame structure W having predetermined workpiece information, for example. Specifically, the “optimal positions of the rotation positioners10at a time when holding the steel frame structure W”, which are calculated by the positioner position calculation means51a, are positions of the rotation positioners10in which it is possible to securely hold the steel frame structure W while enabling the steel frame structure W to be welded without generating a malfunction.

In the present embodiment, the database DB is described as storing the optimal positions of the rotation positioners10at a time when holding the steel frame structure W but is just exemplary. For example, the database DB may also have a configuration in which positions other than the optimal positions of the rotation positioners10at a time when holding the steel frame structure W are stored. Specifically, the positions of the rotation positioners10may not be the optimal positions as long as the rotation positioners10are in a state where the rotation positioners10can hold the steel frame structure W while enabling the steel frame structure W to be welded without generating a malfunction. Therefore, there is no problem that the database DB has a configuration in which positions other than the optimal positions of the rotation positioners10at a time when holding the steel frame structure W are stored.

The positioner position calculation means51ais configured to calculate positions of the rotation positioners10in which the steel frame structure W can be held in the optimal positions, based on the reference position S as the reference position information received from the workpiece position setting mechanism41and workpiece information inputted into the PC51of the control device50in advance.

The program automatic generation means51bis configured to automatically generate an operating program for moving the rotation positioners10and the welding robot30to the optimal positions of the rotation positioners10at a time when holding the steel frame structure W, which are calculated by the positioner position calculation means51a. Note that, the database DB may be data accumulated by a learning device, and AI (Artificial Intelligence) technology can also be used.

The positioner control unit52is configured to control the rotation positioners10and the welding robot30and to move the same to the positions of the rotation positioners10calculated by the positioner position calculation means51a, according to the operating program automatically generated by the PC51.

The welding robot control unit53is to control the welding operation of the welding robot30, and has a synchronous control unit53a. The welding robot control unit53is configured to control an operation of the manipulator32, power that is supplied to the welding torch31, supply of the welding wire and the like to weld a weld part of the steel frame structure W, based on the operating program generated by the PC51on the basis of the workpiece information such as size data, welding position data or gravity center data and the like of the steel frame structure W or an operating program stored in advance in the welding robot control unit.

At this time, the synchronous control unit53ais configured to control an operation of the manipulator32of the welding robot30and an operation of the rotation positioners10so as to be synchronized with each other. Specifically, when welding the arc part of the steel frame structure W by the welding robot30, the welding is performed while synchronizing the rotation of the steel frame structure W and the operation of the welding robot30. In addition, as required, the synchronous control unit53ais configured to move the welding robot30in synchronization with movement of the rotation positioners10moving in the length direction of the steel frame structure W, in response to a command from the PC51.

Subsequently, a welding procedure of the steel frame structure W by the welding system1is sequentially described with reference toFIGS.1,3and5. Note that,FIG.3is an outline configuration view of the welding system shown inFIG.1, as seen from above, andFIG.5is a flowchart showing a welding procedure by the welding system shown inFIG.1.

First, the carriage43for a workpiece position setting mechanism is moved along the moving rails R1for a positioner, and the workpiece position setting mechanism41is positioned to any position. Thereby, the reference surface42of the workpiece position setting mechanism41is set as the reference position S of the steel frame structure W. Note that, although the position of the workpiece position setting mechanism41is arbitrarily determined, it is preferably set the same to a position in which a welding work area of the steel frame structure W does not overlap other work areas, for example.

As shown in step S1inFIG.5, the workpiece information such as size data, welding position data or gravity center data and the like of the steel frame structure W is input in advance to the PC51by an operator's manual input, an input from CAD (Computer-Aided Design) data of the steel frame structure W, and the like. Note that, although the input method of the workpiece information is not particularly limited, 3D CAD data is preferably used from a standpoint of improving work efficiency.

Then, as shown in step S2inFIG.5, the positioner position calculation means51aof the PC51calculates the positions of the rotation positioners10in which the steel frame structure W can be held in the optimal positions, based on the reference position information received from the workpiece position setting mechanism41and the workpiece information input in advance to the PC51of the control device50. Specifically, the positioner position calculation means51aassumes a virtual steel frame structure W whose one end is in contact with the reference surface42of the workpiece position setting mechanism41, and determines the optimal holding positions for the virtual steel frame structure W and calculates the positions of the rotation positioners10, from the database DB in which the optimal positions of the rotation positioners10at a time when holding the steel frame structure W are stored for each of the workpiece information.

Note that, in a case where the gravity center data of the steel frame structure W is included as the workpiece information, the optimal holding positions are calculated, considering the gravity center data, so that the steel frame structure W can be held in a stable state and the welding work can be performed with high accuracy.

As shown in step S3inFIG.5, the program automatic generation means51bof the PC51automatically generates the operating program for moving the rotation positioners10to the positions of the rotation positioners10calculated by the positioner position calculation means51a, and transmits the same to the positioner control unit52.

As shown in step S4inFIG.5, the positioner control unit52moves the carriages14for a rotation positioner along the moving rails R1for a positioner, thereby moving the rotation positioners10to the positions of the rotation positioners10calculated by the positioner position calculation means51a, according to the operating program generated by the program automatic generation means51b.

Note that, the movement of the rotation positioners10to the calculated positions is preferably performed by controlling the position of the driven-side rotation positioner10B, based on the position of the drive-side rotation positioner10A. Thereby, the position accuracy of the drive-side rotation positioner10A and the driven-side rotation positioner10B is increased.

Then, as shown in step S5inFIG.5, the elevating arm mechanisms12are actuated to divide and open the upper parts of the annular holders11(refer toFIG.2A), and the steel frame structure W is then conveyed and mounted on the fixing jigs16by a crane or the like. When mounting the steel frame structure W on the fixing jigs16, one end of the steel frame structure W becoming the reference surface is brought into contact with the reference surface42of the workpiece position setting mechanism41for determining the position in the length direction of the steel frame structure W, and then the steel frame structure is clamped and fixed from all around by the plurality of fixing jigs16. Then, the annular holders11are closed, and the workpiece position setting mechanism41is moved and retreated away from the steel frame structure W. Thereby, the rotation of the steel frame structure W by the rotation positioners10can be performed.

Subsequently, as shown in step S6inFIG.5, the PC51checks that each part has no interference, and as shown in step S7, transfers teaching data such as a welding position, a welding sequence, a welding method and the like to the welding robot control unit53.

The welding robot control unit53starts a welding work of the steel frame structure W by the welding robot30, as shown in step S9, based on an activation command from an external input switch shown in step S8inFIG.8. Specifically, for example, based on the operating program stored in the PC51or the welding robot control unit53, the welding robot control unit53implements the welding work of the steel frame structure W while moving the welding robot30. Note that, the linear part in the length direction of the steel frame structure W is welded without rotating the steel frame structure W while moving the carriage20for a welding device and a control device, specifically, the welding robot30in the length direction of the steel frame structure W along the moving rails R2for a welding device and a control device or moving the slider mechanism22in the direction orthogonal to the length direction of the steel frame structure W. In addition, the linear part may be welded by actuating the manipulator32with 6-axis joints of the welding robot30without moving a main body of the welding robot30.

The arc part of the steel frame structure W is welded by controlling the welding robot30in synchronization with rotation of the fixing jigs16by the synchronous control unit53awhile driving the drive unit M to rotate the annular holders11, thereby rotating the steel frame structure W held by the fixing jigs16.

After the welding of the steel frame structure W is completed, the upper parts of the annular holders11are opened by the elevating arm mechanisms12and the steel frame structure W is carried out, as shown in step S10inFIG.5, so that the welding work is ended.

As described above, according to the welding system of the present embodiment, it is possible to automatically calculate and determine the optimal positions of the rotation positioners10at a time when holding the steel frame structure W, which depends on the operator's experience in the related art. Specifically, it is possible to perform efficient work by automating the work for positioning the rotation positioners10.

Note that, the present invention is not limited to the above embodiment and can be modified and improved as appropriate. For example, in the above embodiment, the pair of rotation positioners10has been described as the holding mechanism of the steel frame structure W. However, one holding mechanism or three or more holding mechanisms can also be possible as long as it is possible to hold the steel frame structure W.

As described above, the present specification discloses following matters.

(1) A welding system configured to weld a workpiece by using a welding device and a positioner, the welding system including:a control device configured to control the welding device and the positioner,wherein the positioner includes a workpiece position setting mechanism having reference position information, and at least one holding mechanism configured to hold the workpiece, andwherein the control device includes a positioner position calculation means for calculating a position of the holding mechanism when holding the workpiece based on the reference position information provided from the workpiece position setting mechanism and workpiece information inputted into the control device in advance.

According to the configuration, it is possible to automatically calculate and determine a position of the positioner at a time when holding the workpiece, so that it is possible to perform efficient work by automating the work for positioning the positioner.

(2) The welding system according to the above (1), wherein the control device has a database in which the position of the holding mechanism at a time when holding the workpiece is stored for each of the workpiece information, andwherein the positioner position calculation means calculates the position of the holding mechanism at a time when holding the workpiece by referring to the database.

According to the configuration, it is possible to calculate holding positions, according to a variety of workpieces.

(3) The welding system according to the above (1) or (2), wherein the workpiece information includes at least one data of welding position data and size data of the workpiece.

According to the configuration, it is possible to correctly perceive a size and a welding position of the workpiece.

(4) The welding system according to one of the above (1) to (3), wherein the control device includes a synchronous control unit configured to perform control such that an operation of the welding device and an operation of the positioner are synchronized with each other.

According to the configuration, it is possible to continuously perform the welding without cutting the arc even when welding an arc part of the workpiece by synchronizing the operations of the welding device and the positioner.

(5) The welding system according to one of the above (1) to (4), wherein the welding device is a welding robot, andwherein each of the welding robot and the positioner has a moving shaft for enabling movement in parallel.

According to the configuration, even when the welding robot and the holding mechanism move, it is possible to keep relative positions of the welding robot and the holding mechanism.

(6) The welding system according to the above (5), wherein the positioner has two or more holding mechanisms,wherein when one of the holding mechanisms is set as a drive-side holding mechanism and other of the holding mechanisms is set as a driven-side holding mechanism, each of the drive-side holding mechanism and the driven-side holding mechanism has a servo motor for positioning to a predetermined position, andwherein the control device is configured to control a position of the driven-side holding mechanism based on a position positioned in the drive-side holding mechanism, with respect to the position of the holding mechanism at a time when holding the workpiece calculated by the positioner position calculation means.

According to the configuration, the position accuracy of the relative positions of the drive-side holding mechanism and the driven-side holding mechanism increases.

(7) The welding system according to one of the above (1) to (6), wherein the control device has a program automatic generation means for automatically generating an operating program for moving the holding mechanism and the welding device to the position of the holding mechanism at a time when holding the workpiece calculated by the positioner position calculation means.

According to the configuration, it is possible to automatically generate the operating program, so that work efficiency is improved.

(8) The welding system according to one of the above (1) to (7), wherein the workpiece information includes gravity center data of the workpiece, andwherein the positioner position calculation means calculates the position of the holding mechanism at a time when holding the workpiece by referring to the gravity center data.

According to the configuration, the holding mechanism can hold the workpiece in a stable state.

(9) A control device of a welding system configured to weld a workpiece by using a welding device and a positioner,wherein the control device is to control the welding device and the positioner, andwherein the control device includes a positioner position calculation means for calculating a position of a holding mechanism of the positioner at a time when holding the workpiece based on reference position information provided from a workpiece position setting mechanism of the positioner and workpiece information inputted into the control device in advance.

According to the configuration, it is possible to automatically calculate and determine a position of the positioner at a time when holding the workpiece, so that it is possible to perform efficient work by automating the work for positioning the positioner.

(10) A control program of a welding system configured to weld a workpiece by using a welding device and a positioner,wherein the control program is to control the welding device and the positioner, andwherein the control program includes a positioner position calculation step of calculating a position of a holding mechanism of the positioner at a time when holding the workpiece based on reference position information provided from a workpiece position setting mechanism of the positioner and workpiece information inputted into the control program in advance.

According to the configuration, it is possible to automatically calculate and determine a position of the positioner at a time when holding the workpiece, so that it is possible to perform efficient work by automating the work for positioning the positioner.

(11) A welding method of welding a workpiece by using a welding device and a positioner, the welding method including:a process of controlling the welding device and the positioner by a control device configured to control the welding device and the positioner,wherein the positioner includes a workpiece position setting mechanism having reference position information, and at least one holding mechanism configured to hold the workpiece, andwherein the welding method includes a process of calculating a position of the holding mechanism at a time when holding the workpiece based on the reference position information provided from the workpiece position setting mechanism and workpiece information inputted into the control device in advance.

According to the configuration, it is possible to automatically calculate and determine a position of the positioner at a time when holding the workpiece, so that it is possible to perform efficient work by automating the work for positioning the positioner.

Although the various embodiments have been described with reference to the drawings, the present invention is not limited thereto. It is apparent to one skilled in the art that a variety of changes or modifications can be made within the scope defined in the claims and are included within the technical scope of the present invention. In addition, the respective constitutional elements in the above embodiments may be arbitrarily combined without departing from the gist of the invention.

The present application is based on Japanese Patent Application No. 2019-067011 filed on Mar. 29, 2019, the contents of which are incorporated herein by reference.

REFERENCE SIGNS LIST