JPS6411516B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a workpiece positioning device for vehicle body assembly, which positions and clamps predetermined workpieces when welding and assembling them in an automobile body assembly process.

As is well known, in the automobile assembly process, many car body components, including panels, are assembled by welding, and each workpiece is positioned and clamped by a workpiece positioning device that serves as a shape receiver for the welding process described above. It is generally served.

FIG. 1 shows an example of the workpiece positioning device, in which 1 is a welding robot equipped with a spot welding gun 2 on its wrist, and 3 is a workpiece positioning device 4.
A gauge post 5 and a locate post 6 are erected on the jig base 3, and the upper end of the gauge post 5 is a shape receiver corresponding to the shape of the workpiece W. Gauge surface 5a
However, there is also a workpiece W on the upper end surface of the locate post 6.
A locating pin 7 to be inserted into the locating hole on the side is provided for each. A clamp device 8 is attached to the gauge post 5, and this clamp device 8 includes a clamper 9 that rotates to open and close with respect to the gauge surface 5a, and a clamper 9 that rotates to open and close with respect to the gauge surface 5a.
As shown in the figure, the workpiece W is positioned by a gauge surface 5a and a locating pin 7, and is firmly clamped by a clamper 8. After that, a spot welding gun 2 is used to position the workpiece W at a predetermined position. Welding is performed.

Note that 11 is a dowel pin that controls the relative positioning of the jig base 3 and the gauge post 5, and the jig base 3 and the locate post 6, and 12 is a mounting bolt.

However, in the case of the above workpiece positioning device, the accuracy of the product after welding is determined by the accuracy of the positioning device, so the jig base 3 and the gauge post 5, as well as the jig base 3 and the locate post 6 and 6 are fixed with mounting bolts 12, and the final accuracy of the jig itself is guaranteed with a dowel pin 11, but the accuracy of the entire positioning device depends on its component parts, the jig base 3 and the gauge post. 5. In some cases, the required accuracy may not be achieved due to the influence of processing accuracy errors of the locate post 6, etc., and assembly errors when assembling each component. There is a problem in that it requires a large amount of man-hours.

In other words, according to the conventional positioning device, since each component is fixed around the jig base 3, it is not easy to correct the accuracy of the positioning device after assembly is completed, and In some cases, a method is often used in which the process from positioning and clamping to welding is performed once using a completed positioning device, and then the machining errors of the work W itself are corrected by the so-called spot matching method on the positioning device side. However, in the conventional case, all the components are fixed, so the gauge surface 5a, the locate pin 7, etc. cannot be easily moved or corrected.

Here, to explain an example of the accuracy correction method in a conventional positioning device, suppose that the gauge surface 5a is set to X ₁ , Y ₁ , Z ₁ , θ ₁ , θ ₂ ,
Assuming that an error of θ ₃ has occurred, for θ ₁ and θ ₂ , cutting or grinding is performed on the contact surface of the gauge post 5 against the upper surface of the base (the shaded area in FIG. 3 A and B), and the gauge post 5 is and jig base 3
Correct the perpendicularity with. On the other hand, for Z ₁ , either a shim plate 13 for height adjustment is inserted between the gauge post 5 and the jig base 3 (Fig. 4A), or the gauge post 5 is attached to the jig base 3 as described above. The contact surface (shaded area in Figure 4B) is corrected by cutting or grinding. Also, θ ₃ , X ₁ ,
For Y ₁ , install bolt 1 of gauge post 5
Perform processing to widen the hole for 2 (Figure 5),
The entire position of the gauge post 5 is corrected on the jig base 3.

As described above, in the case of conventional positioning devices, processing accuracy errors and assembly errors between each component are accumulated at the center of the jig base 3, so correcting them requires a large amount of processing man-hours and disassembly. In addition to requiring assembly man-hours, in severe cases it may require multiple corrections, and in both cases there was a problem of lack of flexibility.

In view of the above-mentioned points, the present invention has been made for the purpose of providing a workpiece positioning device for car body assembly in which the positioning device itself is made flexible to facilitate correction of accuracy errors. Therefore, in the present invention, a gauge plate, a clamp device,
It is characterized in that a jig member such as a locate pin is attached, and the jig member is moved to a predetermined position by the operation of this manipulator.

Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

That is, FIG. 6 shows one embodiment of the present invention, in which a first manipulator 20 and a second manipulator 21 are erected adjacent to each other on a jig base 3. At the tip of the arm of the first manipulator 20, a jig member, that is, a gauge plate 22, which has a gauge surface 22a as a shape receiver corresponding to a predetermined workpiece shape, is attached to the holder 2.
Further, a clamp device 26, which is a jig member consisting of a clamper 24 and an actuator 25, is attached to the gauge plate 22 as described above. On the other hand, the second
A locate post 27 is vertically attached to the tip of the arm of the manipulator 21, and a locate pin 28, which is a jig member, is attached to the tip of the post.
is retained.

These first and second manipulators 2
0 and 21 each move a gauge plate 22, a clamp device 26, and a locate pin 28, which are jig members, to a target position according to the position information by giving electrical position information. As for the form of the manipulators 20 and 21, any one of the articulated type, cylindrical type, rectangular coordinate type, polar coordinate type, etc. may be used alone, or a plurality of them may be selected and combined. In the case of this embodiment, the first manipulator 20 is an orthogonal coordinate type three-axis type robot 29 equipped with actuators M ₁ , M ₂ , M ₃ ,
Articulated type 3 with actuators M ₄ , M ₅ , M ₆
A total of 6 axes type robot 30 is used in combination with a rotary axis type robot 30, while the second manipulator 21 has actuators M ₇ ,
An orthogonal coordinate type three-axis type robot 31 with M ₈ and M ₉ as the main body is used.

The number of axes of each manipulator 20, 21 may be selected and set as necessary, and depending on the installation conditions of the entire positioning device, the jig base 3 may be omitted and each manipulator 20, 21 may be directly operated. It may be installed on the floor etc.

Therefore, according to the workpiece positioning device having the above configuration, when moving the gauge plate 22 and the locate pin 28 when correcting their positions, a predetermined movement amount command value is sent to the control device of each manipulator 20, 21. When the position information is given, only the necessary shafts of the manipulators 20 and 21 are operated, and the gauge plate 22 and locate pin 28 are set at predetermined positions.

For example, as shown in FIGS. 7A, B, and C, θ ₁ , θ ₂ ,
Assuming that errors of θ ₃ , X ₁ , Y ₁ , Z ₁ occur, for θ ₁ move actuator M ₅ in the direction of arrow m ₅ , for θ ₂ move actuator M ₄ in the direction of arrow m ₄ , Further, θ ₃ is corrected by operating the actuator M ₆ in the direction of the arrow m ₆ . Similarly, for X ₁ , actuator M ₁ is operated in the direction of arrow m ₁ , for Y ₁ , actuator M ₂ is operated in the direction of arrow m ₂ , and for Z ₁ , actuator M ₃ is operated in the direction of arrow m ₃ , respectively. . In this case, each actuator is operated via the control device of each manipulator 20, 21 as described above, and each actuator may be operated alone or a plurality of actuators may be operated simultaneously.

In this way, according to the above-mentioned workpiece positioning device, the amount of correction is directly given to the control device as information, without the need for correction processing or disassembly/reassembly of the gauge post or locate post as in the past. This allows the error to be corrected easily and quickly. In addition, since the gauge plate 22 and the locate pin 28 can be moved arbitrarily, it is possible to change the accuracy itself when assembling the workpiece, thereby correcting the accuracy error due to defects in the workpiece shape or the accuracy error of the locating hole to achieve a predetermined value. It is possible to perform positioning.

FIGS. 8A and 8B show other embodiments of the invention.
In this embodiment, one workpiece positioning device can be used for a plurality of workpieces W ₁ and W ₂ that have the same cross-sectional shape and locating hole diameter but different overall shapes, such as workpieces with left and right hands. It is. In other words, in the case of the work W ₁ , the work W ₁ is positioned at the position shown by the solid lines in FIG. _8A and B, while in the case of the work _{W 2} , the gauge plate ₂₂ is positioned by While operating the first manipulator 20 to move,
Similarly, the second manipulator 21 is operated to move the locate pin 28 by X ₂ and Z ₂ to position the workpiece W ₂ at the dashed line position as shown in the figure.

In this way, since the gauge plate 22 and the locate pin 28 can be moved arbitrarily, if the shape of the gauge receiving surface and the locate hole diameter are the same, one unit can be used for positioning multiple workpieces W ₁ and W ₂ . This allows devices to be shared.

As is clear from the above description, according to the present invention, jig members such as gauge plates, clamp devices, and locating pins can be attached to the end of the arm of a manipulator that has degrees of freedom of movement in three or more axes and can be moved to predetermined positions. By configuring it like this,
In addition to easily and quickly correcting accuracy errors in the positioning device, the number of man-hours required for processing, assembling, and achieving accuracy for the positioning device can be significantly reduced. It has the advantage of being able to handle the positioning and clamping of various types of workpieces.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing an example of a conventional workpiece positioning device, Figs. 2A, B, and C, Figs. An explanatory diagram for explaining the error correction method of the device, FIG. 6 is a perspective view showing an embodiment of the workpiece positioning device according to the present invention, and FIGS. 7A, B, and C are the workpiece positioning device shown in FIG. 6. FIGS. 8A and 8B are an explanatory plan view and a front explanatory view showing another embodiment of the present invention. 3... Jig base, 20... First manipulator, 21... Second manipulator, 22...
Gauge plate (jig member), 26...clamp device (jig member), 28...locate pin (jig member), W, _W1 , _W2 ...work.

Claims (1)

[Claims] 1 Vehicle body assembly for positioning and clamping workpieces at welding positions using jig members such as gauge plates, clamp devices, and locating pins that serve as workpiece shape receivers when welding and assembling predetermined workpieces in the automobile body assembly process. In a workpiece positioning device for use in the industry, the jig member is attached to the arm end of a manipulator that has three or more axes of freedom of movement and moves to a target position based on a position command given from the outside. Features: Work positioning device for car body assembly.