JP2007203340A - Automatic welding system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the installation space for automatic welding, to decrease the transfer time for a work, and to easily correspond to the change in the kind of the work to be treated. <P>SOLUTION: A transfer robot 5 is provided between a tack-welding station 4 and a re-welding station 6. The transfer robot 5 is equipped with a plurality of work holding parts 8a, 8b. Charging and discharging operations of the works are carried out by holding a tack-welded work W with the holding part 8a in one side when the tack-welded work W is charged into a work-set attitude controlling jig 7 of the re-welding station 6 and simultaneously holding a welded work W, which is already placed in the work-set attitude controlling jig 7, with the holding part 8b in another side. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an automatic welding system that can reduce and simplify equipment space when welding a body frame of a motorcycle type vehicle such as a motorcycle, and can cope with a change in model.

Conventionally, as an automatic welding system that accurately positions workpieces during welding and does not cause complicated equipment even if the model is changed, a transfer robot is provided with a transport path between the workpiece input station and workpiece discharge station. By positioning a positioner and a pair of articulated robots at each of a plurality of welding stations connected in the middle of the conveyance path, the body frame transported by the transport robot is transferred to each positioner to be an articulated robot. There is a known technology that uses automatic welding. (For example, refer to Patent Document 1.)
JP 2000-158135 A

In addition, in order to improve the operation rate of the transfer robot in the welding line system, a transfer robot is arranged in the vicinity of the work carry-in line and the carry-out line, and a plurality of welds are arranged around the transfer robot. There is also known a technique in which a workpiece is sequentially fed to each welded portion by a transfer robot by providing a workpiece holder in the welded portion. (For example, see Patent Document 2.)
JP-A-8-294781

However, in the case of the automatic welding system as described in Patent Document 1, there is a problem that a large equipment space is required and the time for moving the work is increased due to a long work moving process.
Further, in the case of the welding line system as in Patent Document 2, when a workpiece is transported to a welded portion at a certain location, a new workpiece cannot be thrown in unless a workpiece that already exists at that location is dispensed. In the transfer robot, there is a problem that the movement trajectory of the robot becomes wasteful. In addition, this technique has a problem that it cannot be easily handled when the type of workpiece is changed.

  Therefore, the present invention aims to reduce the equipment space for automatic welding, shorten the work transport time, and easily cope with changes in the type of work to be handled. Objective.

  In order to achieve the above object, the present invention provides a transfer robot between a workpiece input unit and a workpiece discharge unit, and a plurality of welding stations are provided within a movable range of the transfer robot. In addition, when a plurality of gripping units capable of simultaneously gripping a plurality of workpieces are provided and a new workpiece is put into a specific welding station, at the same time the workpiece is gripped by any one gripping portion of the transfer robot, The workpiece that is already present in the welding station is gripped by another gripping portion, and the workpiece loading and unloading operations are continuously performed.

  By arranging a plurality of welding stations within the movable range of the transfer robot in this way, the equipment space can be reduced, and a plurality of gripping portions can be provided on the transfer robot so that workpiece loading and unloading operations can be performed continuously. By doing so, it is possible to eliminate the waste of the movement trajectory of the transfer robot.

In the present invention, a multi-model support mechanism for gripping multiple types of workpieces is provided in the gripping portion of the transfer robot.
And as a multi-model support mechanism when the workpiece is a body frame of a motorcycle type vehicle, after fixing the head pipe, a head pipe fixing portion where the tilt angle becomes free, and a frame clamp that clamps a predetermined part of the rear frame Provide a part.

And, after fixing the head pipe of the body frame with the head pipe fixing part, if the tilt angle of the head pipe fixing part is made free, the head pipe inclination angle and the work where the positional relationship between the head pipe and the rear frame is different However, a predetermined clamp location can be clamped simply by sliding the frame clamp portion in a predetermined one-axis direction, and can easily handle all types of workpieces. In addition, the multi-model support mechanism can be reduced in weight.
The motorcycle type vehicle includes a motorcycle, a two-wheeled vehicle, a four-wheeled motorcycle, a three-wheeled motorcycle, and the like.

A plurality of welding stations are disposed within a movable range of the transfer robot disposed between the workpiece input unit and the workpiece discharge unit, and a plurality of gripping units capable of simultaneously holding a plurality of workpieces on the transfer robot. When a new workpiece is put into a specific welding station, the feeding workpiece is gripped by any one gripping part of the transfer robot, and at the same time, the dispensing that already exists at the welding station at the other gripping part. If the workpiece is gripped and the workpiece loading and unloading operations are performed continuously, the equipment space can be reduced and the conveyance robot can efficiently carry the workpiece when sequentially loading workpieces into the welding station. Can do.
And as a multi-model compatible mechanism when the work is a body frame of a motorcycle type vehicle, after fixing the head pipe, the head pipe fixing part where the tilt angle becomes free, and the frame clamping part that clamps a predetermined part of the rear frame This allows the rear frame to be clamped on any model body frame by simply sliding the frame clamp in one axis direction, and can easily handle all types of workpieces. Weight can be reduced.

Embodiments of the present invention will be described with reference to the accompanying drawings.
Here, FIG. 1 is an overall view showing an example of a configuration outline of the automatic welding system, FIG. 2 is an explanatory view of a transfer robot, FIG. 3 is a perspective view showing an example of a body frame of a two-wheeled motorcycle type vehicle, and FIG. FIG. 5 is an explanatory diagram showing an example of the work gripping procedure by the transfer robot, and FIG. 6 is a work set / posture control process arranged at the additional hitting station. FIG. 7 is an explanatory view showing an example of a work holding procedure using a work set / posture control jig, and FIG. 8 is an explanatory view showing an example of work posture control using the work set / posture control jig.

  The automatic welding system according to the present invention reduces the equipment space for automatic welding of workpieces, shortens the workpiece transfer time, and easily copes with changes in the type of workpieces to be handled. In this embodiment, the present invention is applied to a welding process for a body frame of a motorcycle vehicle.

  That is, as shown in FIG. 1, the automatic welding system 1 includes a component setting unit 3 in which an operator manually sets a component on a tacking jig 2, and a tacking treatment carried from the component setting unit 3. A tacking station 4 that tacks and welds parts on the tool 2 with a welding robot (not shown), a transfer robot 5 that transports the workpiece W tacked in the tacking station 4 to the additional hitting station 6, and an additional hitting station 6 Is provided with a work set / posture control jig 7, and the transfer robot 5 is configured to deliver the temporarily attached work W to the work set / posture control jig 7. A permanent welding is performed on the posture control jig 7 by a welding robot (not shown). The part setting unit 3 is used as a workpiece input unit, and a workpiece payout unit (not shown) is provided within the movable range of the transfer robot 5. It is held by the transfer robot 5 and paid out to the work paying-out part.

Here, if a plurality of welding stations such as the tacking station 4 and the additional hitting station 6 are provided within the movable range of one transport robot 5, the equipment space can be reduced. As roles, it is necessary to fulfill both the role of transporting the work tacked at the tacking station 4 to the additional hitting station 6 and the role of transporting the workpiece W attached at the additional hitting station 6 to the workpiece dispensing unit. For this reason, generally, the movement path of the robot hand of the transfer robot 5 tends to be wasted.
For this reason, in the present invention, wasteful movement trajectory of the transfer robot 5 is eliminated, and at the same time, even when the type of the workpiece W is changed, it is possible to easily cope with it. Applicable to frame welding.

  That is, as shown in FIG. 2, the transfer robot 5 includes a pair of upper and lower gripping portions 8a and 8b at the tip of a robot arm configured as an articulated robot. The workpiece W can be gripped simultaneously.

  The gripping portions 8a and 8b are provided in the same form in a vertically symmetrical manner based on the central axis x of the arm 10, and the arm 10 is rotatable around the central axis x. For this reason, the grips 8a and 8b on any side can be turned downward, and the tip of the arm 10 is provided for holding the head pipe of the body frame of the motorcycle type vehicle. The head pipe fixing portions 11a and 11b and an air cylinder 13 for changing the inclination angle of the insertion bar i of the head pipe fixing portions 11a and 11b are provided. 10s are provided. The insertion bar i of the head pipe fixing portions 11a and 11b is structured to be fixed in the head pipe by, for example, an expandable / contractible claw chuck mechanism after being inserted into the head pipe.

  Each slide portion 10s is provided with a pair of left and right frame clamp portions 14a, 14b in the direction perpendicular to the paper surface so as to be slidable in the direction of the arrows, and at a position slightly inward from the head pipe fixing portions 11a, 11b. Are provided with front fixing portions 15a and 15b for clamping a front frame of a four-wheel motorcycle type vehicle, and the clamp portions are movable forward and backward in the direction of the arrow. The one side gripping portion 8a is configured by the frame clamp portion 14a on the same side as the head pipe fixing portion 11a and the front fixing portion 15a, and the frame clamp portion 14b on the same side as the head pipe fixing portion 11b on the other side. The grip portion 8b on the other side is constituted by the front fixing portion 15b.

  And, in any of the gripping parts 8a, 8b, in the case of a motorcycle type vehicle, the insertion bar i of the head pipe fixing part 11a, 11b is inserted into the head pipe a of the work W shown in FIG. The frame clamp portions 14a and 14b clamp and clamp the predetermined position c of the rear frame of the workpiece W from both sides. In the case of a four-wheeled motorcycle type vehicle, the front frame is clamped by the front fixing portions 15a and 15b. A predetermined clamping position of the rear frame of the workpiece W is clamped from both sides by the clamp portions 14a and 14b and clamped.

Here, an example of the difference in the form of the body frame of the two-wheeled motorcycle type vehicle will be described with reference to FIG.
The relationship between the horizontal and vertical distances of the head pipe a and rear frame clamp position c (indicated by hatching) and the pivot b of the motorcycle body frame and the pivot b, and the inclination angle of the head pipe a all depend on the type of workpiece W. Is different.

For this reason, when the workpiece W is gripped by the gripping portions 8a and 8b of the transfer robot 5, the inclination angle of the insertion bar i of the head pipe fixing portions 11a and 11b is of course adjusted according to the model. By simply inserting and fixing i into the head pipe a, the desired clamp position c of the rear frame cannot be clamped unless the frame clamp portions 14a and 14b are moved in two horizontal and vertical directions.
However, if the frame clamp portions 14a and 14b are moved in the biaxial direction, the apparatus becomes complicated and the weight increases. In this case, the weight of the robot arm tip increases, which is not preferable.

Therefore, in the present invention, when gripping the workpiece W by the transfer robot 5, first, the inclination angle of the insertion bar i of the head pipe fixing portions 11a and 11b is determined by the operation of the air cylinder 13, and the inclination of the head pipe a of the model to be handled. After adjusting to the corner, it is inserted and fixed in the head pipe a, and then the pressure of the air cylinder 13 is released so that the inclination angle of the insertion bar i becomes free, and then the frame clamp portions 14a and 14b are slid. Thus, a desired clamp position c of the rear frame is gripped.
By adopting such a gripping method, as shown in FIG. 5, even if the inclination angle of the head pipe a and the positional relationship to the desired clamp position c of the rear frame differ depending on the model, the frame clamp The desired clamping position c can be gripped simply by sliding the portions 14a and 14b in one axis direction, and the apparatus can be simplified and reduced in weight.

Next, the work set / posture control jig 7 disposed in the additional hitting station 6 will be described with reference to FIGS.
The work set / posture control jig 7 includes a rotating body 22 that is rotatable around a pivot shaft 21 with respect to a base 20, and a head pipe fixing portion 23 provided on the rotating body 22 closer to the base 20. An air cylinder 24 for changing the inclination angle of the insertion bar j of the head pipe fixing portion 23, a pair of left and right pivot support tables 26 slidably provided on a slide table 25 of the rotating body 22, and a slide table 25 The pivot support base 26 is slidable in the direction of the arrow in FIG. 6 by the operation of the drive motor 28, and each pivot support base 26 is provided. A reference pin portion 27 capable of supporting the left and right pivots b of the vehicle body frame is provided on the upper portion of the body frame. Further, the insertion bar j of the head pipe fixing portion 23 is structured such that it can be fixed in the head pipe a by, for example, an expandable / contractible claw chuck mechanism after being inserted into the head pipe a.

When the workpiece W is held by the workpiece set / posture control jig 7, it is possible to adjust the inclination angle of the insertion bar j of the head pipe fixing portion 23 in accordance with the inclination angle of the head pipe a of the vehicle body frame corresponding to the model. Of course, if the pivot support 26 is not moved in the vertical and horizontal biaxial directions simply by inserting the insertion bar j into the head pipe a and fixing it, the reference pin 27 is positioned at the desired pivot b. Can not be matched.
Therefore, in the present work set / posture control jig 7, after the inclination angle of the insertion bar j of the head pipe fixing portion 23 is adjusted to the inclination angle of the head pipe a of the model to be handled by the operation of the air cylinder 24, the head After inserting and fixing in the pipe a, the pressure of the air cylinder 24 is released so that the inclination angle of the insertion bar j becomes free, and then the pivot support 26 is slid only in one axial direction to move the pivot b. It can be held.

By adopting such a holding method, as shown in FIG. 7, even if the inclination angle of the head pipe a and the horizontal and vertical distances to the position of the pivot b are different depending on the model, the pivot support 26 can be mounted. The pivot b can be held by the reference pin portion 27 only by sliding in one axial direction, and the device can be simplified and reduced in weight.
Note that the pivots b on both sides of the vehicle body frame are held by the work set / posture control jig 7 because it is necessary to accurately position and hold at the welding stage. The clamp position c is gripped because a very accurate positioning is not required at the transport stage.

  As shown in FIG. 8, the posture of the workpiece set on the workpiece setting / posture control jig 7 is such that the rotating body 22 is rotatable around the pivot shaft 21 and the pivot shaft 21 and the reference posture. Since it can be freely rotated around the axis y connecting the pin portions 27, the posture of the workpiece W can be arbitrarily changed, welding can be performed from the optimum direction, and the spatter generation direction during welding can be determined. Can be welded in a posture that does not cause any problems.

The operation of the automatic welding system 1 as described above will be described.
In the component setting unit 3 of FIG. 1, an operator sets an assembly part on the temporary attachment jig 2, and then transports the temporary attachment jig 2 to the temporary attachment station 4. Then, in the tacking station 4, tack welding of parts is performed by a welding robot (not shown).

  When the parts are tack-welded on the tacking jig 2, the transfer robot 5 operates and grips the workpiece W with the gripping portion 8b on either side. That is, by operating the air cylinder 13, the inclination angle of the insertion bar i of the head pipe fixing portion 11b is adjusted to the predetermined inclination angle of the head pipe a, and then inserted into the head pipe a from above and fixed. Then, the pressure of the air cylinder 13 is released so that the inclination angle of the insertion bar i becomes free, and then the frame clamp portion 14b is slid to grip the clamp position c of the rear frame.

Next, the gripped work W is conveyed to the additional hitting station 6, and the work W is delivered to the work set / posture control jig 7. At this time, the work set / posture control jig 7 has a previous stage. Since there is a workpiece W that has been permanently welded, the temporarily welded workpiece W cannot be delivered unless the workpiece W that has been permanently welded is dispensed.
Therefore, the transport robot 5 rotates 180 degrees around the central axis x and the other gripping portion 8a faces downward, and after the gripping workpiece W is gripped by the gripping portion 8a, it is reversed again. The work W temporarily attached is transferred to the work set / posture control jig 7.

  That is, in the work set / posture control jig 7, after the inclination angle of the insertion bar j of the head pipe fixing portion 23 is adjusted to a predetermined inclination angle of the head pipe a by the operation of the air cylinder 24, After that, the pressure of the air cylinder 24 is released so that the inclination angle of the insertion bar j becomes free, and then the pivot support 26 is slid only in one axial direction, and each reference pin is 27 holds the left and right pivot b. When the workpiece setting / posture control jig 7 holds the workpiece W, the gripping portion 8b of the transfer robot 5 releases the gripping, and transfers the workpiece W gripped by the gripping portion 8a on the other side to the workpiece dispensing portion. To do.

  By the above procedure, the movement trajectory of the transfer robot 5 can be minimized, and transfer efficiency can be improved.

  In the work set / posture control jig 7, when the workpiece W is positioned and welded, as shown in FIG. 8, the workpiece W is welded from an optimum direction by arbitrarily changing the posture of the workpiece W. In addition, it is possible to avoid the adverse effect of spatter during welding on the workpiece W.

  In the above embodiment, the body frame of the two-wheeled motorcycle type vehicle has been described as an example. However, in the case of gripping the four-wheeled motorcycle type vehicle, in the transfer robot 5, the front fixing portions 15a and 15b and the frame clamp portion 14a. 14b, and in the work set / posture control jig 7, the front fixing portion 30 and the reference pin 27 of the pivot support 26 are used.

  Further, in the above-described embodiment, the gripping portions 8a and 8b are provided at two locations on the transfer robot 5, but may be provided at three or more locations, and further, at three or more welding stations within the movable range of the transfer robot 5. May be provided.

  As described above, by providing a plurality of gripping units on one transfer robot in automatic workpiece welding, the workpiece can be discharged and put in efficiently, so that work efficiency such as automatic welding of progressive workpieces can be improved. Can be improved. In addition, it is highly versatile because it can be applied to workpieces of different models.

Overall view showing an example of the configuration outline of this automatic welding system Illustration of transfer robot A perspective view showing an example of a body frame of a motorcycle type vehicle Explanatory drawing which shows an example of the difference in the form by the model of the body frame of a motorcycle type vehicle Explanatory drawing showing an example of the work gripping procedure by the transfer robot Explanatory drawing of the work set / posture control jig placed in the additional hitting station Explanatory drawing showing an example of work holding procedure by work set / posture control jig Explanatory drawing showing an example of workpiece posture control by workpiece set / posture control jig

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Automatic welding system, 2 ... Tacking jig, 4 ... Tacking station, 5 ... Conveying robot, 6 ... Strike station, 7 ... Work set and posture control jig, 8a, 8b ... Gripping part, 11a, 11b ... head pipe fixing part, 14a, 14b ... frame clamp part, W ... workpiece, a ... head pipe, b ... pivot, c ... rear frame clamp position.

Claims (3)

A transfer robot is disposed between the workpiece input unit and the workpiece discharge unit, a plurality of welding stations are disposed within the movable range of the transfer robot, and a plurality of workpieces can be simultaneously gripped by the transfer robot. When a new workpiece is put into a specific welding station, a workpiece can be held at one of the transfer robots at the same time, and at the same time, the welding can be done at another holding portion. An automatic welding system characterized in that a workpiece to be dispensed that already exists in a station is gripped and workpieces are loaded and dispensed continuously. The automatic welding system according to claim 1, wherein the gripping portion of the transfer robot includes a multi-model support mechanism for gripping multi-model workpieces. The workpiece is a body frame of a motorcycle type vehicle, and the multi-model support mechanism includes a head pipe fixing portion that allows a tilt angle to be free after fixing the head pipe, and a frame clamp portion that clamps a predetermined portion of the rear frame. The automatic welding system according to claim 2, wherein the automatic welding system is provided.