JP5239572B2 - Robot apparatus and workpiece assembling method - Google Patents

Description

  The present invention relates to a work assembly technique that enables a work or a non-weld tool to be gripped by a welding tool including a welding gun and a servo gun.

In assembly lines such as automobiles, when handling different processes such as welding and sealers and workpieces, dedicated robot devices and tool changers have been provided for each process. Here, Patent Document 1 describes a welding robot in which a robot arm having a welding gun is provided with clamping means for gripping a workpiece and positioning means for positioning the workpiece at a welding position.
JP 2000-254784 A

  As described above, conventionally, since a separate robot apparatus and tool changer are required for each process, there are limits to simplification of assembly lines, reduction of capital investment, and reduction of tool changeover time.

  The present invention has been made in view of the above-described problems, and the object of the present invention is that the same robot apparatus can be used for different processes, and it is possible to simplify the assembly line, reduce capital investment, and reduce work time. It is to realize assembly technology.

In order to solve the above-described problems and achieve the object, a first embodiment according to the present invention is to grip a welded part of a workpiece with a welding tool including a welding gun and a servo gun attached to a robot arm. A robot mechanism for welding to a servo mechanism, wherein the gripping pressure of the welding tool is variable, and the servo mechanism is controlled to grip the workpiece or the non-welding tool by adjusting the gripping pressure of the welding tool. and control means possess for the control means, the gripping pressure of the workpiece or non-welded tool by the welding tool, the pressure lower than the gripping pressure during welding.

  Further, according to another aspect of the present invention, there are provided a welding tool including a welding gun and a servo gun attached to a robot arm, a servo mechanism that varies a gripping pressure of the welding tool, and a control unit that controls the servo mechanism. A workpiece assembly method by a robot apparatus that grips a welded portion of the workpiece with the welding tool and welds the welded portion, and after the workpiece is welded, the servomechanism The gripping pressure by the welding tool is adjusted to grip the workpiece or the non-welding tool, and the workpiece gripped by the welding tool is transferred to another process, or is separated by using the non-welding tool gripped by the welding tool. The process is executed.

  According to these embodiments, the same robot apparatus can be used for different processes, and the assembly line can be simplified, the capital investment can be reduced, and the working time can be reduced.

Usually, the gripping pressure at the time of welding is high, but if the non-welding tool is gripped by the gripping pressure at the time of welding, the reliability of the non-welding tool becomes a problem. Therefore , the holding pressure of the workpiece or the non-welding tool by the welding tool is set to a pressure lower than the holding pressure at the time of welding. Thereby, a non-welding tool can be grasped appropriately.

  According to another aspect of the present invention, the non-welding tool has a gripped portion gripped by the welding tool, and the gripped portion is positioned by engaging with the servo gun. Is provided. Thereby, rocking | fluctuation of a non-welding tool can be suppressed and work precision can be improved.

  According to another aspect of the present invention, the gripped portion of the non-welding tool is provided with a positioning portion through which the electrode portion of the welding gun penetrates and is positioned while being gripped by the welding tool. Yes. Thereby, the displacement of a non-welding tool can be suppressed and work accuracy can be improved.

Another embodiment according to the present invention, the in the gripped portion of the non-welded tool includes a first plate member abutting said servo gun when it is gripped by the welding tool abuts against the welding gun A second plate member, and a buffer member that is applied between the first plate member and the second plate member and applies a force against a gripping pressure when gripped by the welding tool. Is provided. Thereby, the impact at the time of gripping a non-welding tool can be relieved.

  In another embodiment according to the present invention, the workpiece is a sheet metal member for an automobile, and the non-welding tool is a sealer gun for applying a sealant to the workpiece. Thereby, a welding process and a sealing process can be implemented by the same robot apparatus.

According to the present invention, the same robot apparatus can be used for different processes, and the assembly line can be simplified, the capital investment can be reduced, and the working time can be shortened. Moreover, a non-welding tool can be appropriately gripped.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The embodiment described below is an example as means for realizing the present invention, and the present invention can be applied to a modified or modified embodiment described below without departing from the spirit of the present invention.
[Configuration of assembly line]
FIG. 1 is a plan view of an automobile assembly line according to an embodiment of the present invention.

  As shown in FIG. 1, the robot apparatus 10 of this embodiment is installed in an assembly line L of an automobile, and a process of welding a component such as a reinforcement to a workpiece W made of a sheet metal member such as a fender panel of a vehicle body, The step of applying a sealant to the workpiece to which the above parts are welded is performed.

  The robot apparatus 10 includes a robot body 1, a robot arm 2 that can move in a three-dimensional direction with respect to the robot body 1, a turntable 3 that holds a workpiece W via a jig 5, and a sealer gun 30 described later. A tool storage place 4 is provided.

  A welding tool 20 described later is attached to the tip of the robot arm 2.

The workpiece | work W which finished the said welding process and the sealing process is thrown into another adjacent process.
[Configuration of welding tool]
2 and 3 are perspective views showing a detailed configuration of the welding tool of the present embodiment, and show a state where the grip of the sealer gun is released by dotted lines.

  As shown in FIG. 2, the welding tool 20 includes a welding gun 21 and a servo gun 22 attached to the distal end portion of the robot arm 2. The welding tool 20 grips the welded part of the workpiece W and spot welds the welded part. To implement. Electrode portions 21a and 22a for welding are detachably attached to portions of the welding gun 21 and the servo gun 22 that face each other, and the workpiece W is sandwiched between the welding gun 21 and the servo gun 22 with a predetermined gripping pressure, and one electrode portion. Welding is realized by applying a predetermined current from 21a (22a) to the other electrode portion 22a (21a).

  The welding tool 20 holds the workpiece W or the non-welding tool 30.

  The robot apparatus 10 includes a servo mechanism 61 (see FIG. 4) that adjusts the gripping pressure of the welding tool 20 (servo gun 22). The servo mechanism 61 uses the servomotor to increase the gripping pressure by the welding tool 20 from the gripping pressure during welding. The workpiece W or the non-welding tool 30 is held at a low pressure.

  The non-welding tool 30 is, for example, a sealer gun that applies a sealant to the workpiece W.

  The non-welding tool 30 has a gripped portion 31 gripped by the welding tool 20, and the gripped portion 31 is provided with a first positioning portion 32 that is positioned by engaging with the servo gun 22. .

  In addition, the gripped portion 31 of the non-welding tool 30 is provided with a second positioning portion 33 in which the electrode portion 21 a of the welding gun 21 penetrates and is positioned while being gripped by the welding tool 20.

  Furthermore, the gripped portion 31 of the non-welding tool 30 includes a first plate member 34 that contacts the servo gun 22 side when gripped by the welding tool 20 and a second plate member 35 that contacts the welding gun 21 side. And a pair of buffer members 36 that apply a force against the gripping pressure when being stretched between the first plate member 34 and the second plate member 35 and gripped by the welding tool. ing.

  The buffer member 36 is fixed to one plate member 35 at both ends of the first plate member 34 and the second plate member 35, and the other plate member 34 has a pair of shaft portions 36 a penetrating therethrough. A coil spring 36b is wound around each shaft portion 36a. As a result, the first plate member 34 and the second plate member 35 can move along the shaft portion 36a while resisting the urging force of the spring 36b, so that the sealer gun 30 is gripped by the welding tool 20. Can reduce the impact.

  The sealer gun 30 is attached to the end portion of the first plate member 34 on the servo gun 22 side via the arm portion 37.

  The first positioning portion 32 is provided on the outer surface side of the first plate member 34, and the second positioning portion 33 is provided on the inner surface side of the first plate member 34.

  The first positioning portion 32 includes a pair of wall portions 32a protruding from the first plate member 34 so as to sandwich both sides of the arm portion 22b of the servo gun 22, and a plane portion 32b disposed between the wall portions 32a. And have. As described above, the first positioning portion 32 abuts the outer peripheral surface of the arm portion 22b of the servo gun 22 at three points at 90 ° intervals, so that the first plate member 34, that is, the sealer gun 30 is attached to the servo gun 22. It is possible to prevent the arm portion 22b from swaying in the A direction, and to ensure the work accuracy of the sealer gun 30.

  Further, since the second positioning portion 33 is provided with a positioning hole 33a through which the electrode portion 21a of the welding gun 21 passes while being held by the welding tool 20, the sealer gun 30 is provided with the arm portion 22b of the servo gun 22. On the other hand, it is possible to suppress displacement in the B direction, and it is possible to ensure work accuracy by the sealer gun.

Further, the second plate member 35 is formed with a curved surface portion 35 a that contacts the outer peripheral surface of the arm portion 21 b of the welding gun 21.
[Work assembly procedure]
Next, a procedure for assembling a workpiece by the robot apparatus according to this embodiment will be described.

  FIG. 4 is a block diagram of the robot apparatus according to the present embodiment, and FIG. 5 is a flowchart showing a procedure for assembling a workpiece by the robot apparatus according to the present embodiment.

  As shown in FIG. 4, in the operation of the robot apparatus 10, the control unit 60 controls the robot arm 2, the welding gun 21, the servo gun 22, the sealer gun 30, and the servo mechanism 61 according to the rotational position of the turntable 3.

  In FIG. 5, first, the welding tool 20 is driven, and welding is performed on the workpiece W held on the turntable 3 via the jig 5 (S1).

  Next, the servo mechanism 61 is controlled so that the gripping pressure by the welding tool 20 is set to a pressure (400 to 500 N) lower than the gripping pressure (2 to 5 kN) during welding, and the robot arm 2 is moved to the tool place 4. Then, the workpiece W or the sealer gun 30 as a non-welding tool is gripped (S2, S3).

  Next, the robot arm is moved to the workpiece W, and the sealing process is performed by the sealer gun 30 gripped by the welding tool 20 (S4).

  Next, the robot arm 2 is moved to the tool place 4 to release the grip of the sealer gun 30, and the sealer gun 30 is returned to the tool place 4 (S5).

  The operations of S1 to S5 are repeatedly executed until there is no next workpiece (S6).

  In the above-described embodiment, the configuration in which the sealer gun 30 is gripped by the welding tool 20 has been described. However, the present invention is not limited to this. For example, after applying welding and a sealant to the workpiece W (S1, S4), It is also possible to grip the workpiece W by the welding tool 20 and transfer it to the subsequent process, or to grip the workpiece that has been subjected to the previous process and put it into the present process.

  According to the above embodiment, since the welding process and the sealing process can be performed by the same robot apparatus 10 without affecting the welding process, the assembly line can be simplified, the capital investment can be reduced, and the working time can be shortened. it can.

It is a top view of the assembly line of the car of the embodiment concerning the present invention. It is a perspective view which shows the detailed structure of the welding tool of this embodiment. It is a perspective view which shows the detailed structure of the welding tool of this embodiment. It is a block diagram of the robot apparatus of this embodiment. It is a flowchart which shows the assembly procedure of the workpiece | work by the robot apparatus of this embodiment.

DESCRIPTION OF SYMBOLS 1 Robot body 2 Robot arm 3 Turntable 4 Tool place 5 Jig 20 Welding tool 21 Welding gun 22 Servo gun 30 Sealer gun 31 Grasping part 32 First positioning part 33 Second positioning part 34 First plate member 35 First Two plate members 36 Buffer member 60 Control unit 61 Servo mechanism L Assembly line W Workpiece

Claims (11)

A robot apparatus that grips a welding position of a workpiece with a welding tool including a welding gun and a servo gun attached to a robot arm and welds the welding position,
A servomechanism that makes the gripping pressure of the welding tool variable;
By adjusting the gripping pressure of the welding tools have a control means for controlling the servo mechanism to grip the workpiece or non-welded tool,
The said control means makes the holding pressure of the said workpiece | work or non-welding tool by the said welding tool the pressure lower than the holding pressure at the time of welding, The robot apparatus characterized by the above-mentioned . The non-welding tool has a gripped portion gripped by the welding tool,
Wherein the gripped portion is a robot apparatus according to claim 1, wherein a positioning portion to be positioned in engagement with the servo gun is provided. Wherein the retained portion of the non-welded tool, according to claim 2, characterized in that the positioning portion electrode portion of the welding gun in a state of being gripped by the welding tool is positioned to penetrate it is provided Robotic device. Wherein the retained portion of the non-welded tools, a first plate member abutting said servo gun when it is gripped by the welding tool, and a second plate member which abuts with the welding gun, the first A buffer member is provided, which is provided between the plate member and the second plate member and applies a force against a gripping pressure when gripped by the welding tool. The robot apparatus according to 2 . The workpiece is a sheet metal member for an automobile, the non-welded tool robot apparatus according to any one of claims 1 to 4, characterized in that a sealer gun for applying a sealing agent to the workpiece. A welding tool comprising a welding gun and a servo gun attached to a robot arm, a servo mechanism for changing a holding pressure of the welding tool, and a control means for controlling the servo mechanism, and welding a workpiece with the welding tool. A method of assembling a workpiece by a robot apparatus that grips a spot and welds the weld spot,
After performing welding on the workpiece, the workpiece or the non-welding tool is gripped by adjusting the gripping pressure by the welding tool by the servo mechanism,
A method for assembling a workpiece, wherein the workpiece gripped by the welding tool is transferred to another step, or another step is executed using a non-welding tool gripped by the welding tool. The work assembly method according to claim 6 , wherein a gripping pressure of the work or the non-welding tool by the welding tool is set to a pressure lower than a gripping pressure at the time of welding. The non-welding tool has a gripped portion gripped by the welding tool,
Wherein the gripped portion is assembling method of a work according to claim 6 or 7, characterized in that the positioning portion to be positioned in engagement with the servo gun is provided. Wherein the retained portion of the non-welded tool, according to claim 8, characterized in that the positioning portion electrode portion of the welding gun in a state of being gripped by the welding tool is positioned to penetrate it is provided To assemble the workpiece. Wherein the retained portion of the non-welded tools, a first plate member abutting said servo gun when it is gripped by the welding tool, and a second plate member which abuts with the welding gun, the first A buffer member is provided, which is provided between the plate member and the second plate member and applies a force against a gripping pressure when gripped by the welding tool. 9. A method for assembling the workpiece according to 8 . The workpiece is a sheet metal member for an automobile, the non-welding tool assembly method of a work according to any one of claims 6 to 10, characterized in that a sealer gun for applying a sealing agent to the workpiece.

Images