JPS6057957B2 - Work positioning jig - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a workpiece positioning jig, and more particularly to a positioning jig for positioning a predetermined workpiece when welding and assembling the workpiece in an automobile assembly process.

For example, in the automobile assembly process, many car body components, including panels, are assembled by welding, but each workpiece has a positioning jig that serves as a shape receiver, that is, a gauge plate that corresponds to the cross-sectional shape of the workpiece. Generally, the material is positioned and clamped at a holder and then subjected to the above-mentioned welding.

Fig. 1 shows an example of the conventional positioning jig, in which 1 is a welding robot equipped with a spot welding gun 2 on the wrist part 1a, 3 is a jig base, and on this jig base 3 there is a gauge. A post 5 and a locate post 6 are installed upright, a gauge plate 7 having a gauge surface 7a as a shape receiver corresponding to the shape of the workpiece W is provided at the upper end of the gauge post 5, and a gauge plate 7 having a gauge surface 7a as a shape receiver corresponding to the shape of the workpiece W is placed on the locate post 6. A locating pin 8 inserted into the locating hole on the side is attached to each via a holder 9.

A clamp device 10 is attached to the gauge plate 7, and this clamp device 10 is attached to the gauge plate 7.
It consists of a clamper 11 that rotates to open and close with respect to a, and an actuator 12 that drives the clamper 11 to open and close.As shown in the figure, the workpiece W is positioned by the gauge surface 7a and the locating pin 8, and the clamper 11 Clamp firmly, then use spot welding gun 2.
Predetermined welding is performed at. Note that 13 is a knock pin that controls the relative positioning of the jig base 3 and the gauge post 5 or the locate post 6, and 14 is a mounting bolt.

However, with such conventional positioning jigs,
Since the accuracy of the product after welding is determined by the accuracy of the positioning jig, the gauge plate 7 and the gauge post 5, as well as the holder 9 of the locate pin 8 and the locate post 6, are fixed to each other, and The gauge post 5 and locate post 6 are fixed to the jig base 3 with mounting bolts 14, and the final accuracy of the jig itself is ensured with knock pins 13. Therefore, the gauge plate 7 The shape and the diameter of the gate pin 8 are limited to one type of workpiece W and are specialized.

For this reason, for example, in a so-called mixed production system where multiple car models are assembled on the same line, it is not possible to handle multiple car models unless the entire jig, including the jig base, is replaced, resulting in a lack of versatility. be. Therefore, a so-called switching type positioning jig as shown in FIG. 2 has been considered as an alternative to the above-mentioned positioning jig.

As shown in the figure, a plurality of gauge posts 15 having a plurality of rotatable gauge plates 7A are arranged in parallel horizontally, and these plurality of... By selecting only the gauge plate having the required gauge surface from among the gauge plates 7A and standing it upright, it is possible to adapt to a plurality of workpieces. However, in the case of the above-mentioned switchable positioning jig, the basic structure of the device itself increases the size of the device itself, and there is a limit to the number of gauge plates that can be installed. But right now, I'm not necessarily in a situation where I'm fully satisfied.

In view of the above points, this invention was made with the aim of making the jig itself more versatile.For this purpose, in the present invention, the gauge plate itself is made of a large number of strip-shaped thin plates. The gauge is characterized in that it is constructed of a laminated body of thin plates, and by vibrating this laminated body of thin plates with a vibrator unit, an arbitrary gauge surface shape can be created.

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

That is, FIG. 3 shows one embodiment of the present invention, in which a gauge plate, which is a welding jig of the present invention, is combined with an industrial robot, which is a manipulator.

In the figure, 20 is a jig base, 21 is an orthogonal coordinate type 3-axis industrial robot, and each industrial robot 21 moves in the X, Y, and Z directions by the operation of actuators M1, M2, and M3. A gauge unit 23 is attached to each wrist part via a bracket 22.
The gauge unit 23 is constructed as shown in FIGS. 4 and 5, with reference numeral 24 a housing, 25 a pair of holder plates, 26 a side plate, and 27 a clamp plate arranged in parallel with one holder plate 26. in,
In the area surrounded by the side plate 26 and the holder plate 25, a thin plate laminate 28 formed by aligning and stacking a large number of strip-shaped thin plates (steel plates) 28a is arranged together with a substrate 29, thereby forming a gauge. A plate 30 is configured.

As shown in FIG. 6A, the clamp plate 27 has a plurality of (three) cylinders 31 built-in, and as described later, the thin plates 28a are moved individually to form the tip of the thin plate stack 28. After creating the desired bulge surface 32 on the side, the cylinder 31 is extended to press and clamp the thin plate laminate 28 in the stacking direction to maintain the shape of the gauge surface 32. It's like this. The above side plate 26, clamp plate 27, and cylinder 31 constitute a tightening mechanism 60. Each of the thin plates 28 has elongated holes 33 as shown in FIGS. 7A and 7B.
A rod 34 is disposed so as to pass through the elongated holes 33 of all the thin plates 28a including the substrate 29.

On the other hand, each side plate 26 has a cylinder 3 inside it.
5, and a slide plate 36 that slides by the operation of this cylinder 35 is built in, and this slide plate 36 is connected to the rod 34 mentioned above. When the cylinder 35 is extended and the slide plate 36 is slid to its stroke limit as shown in FIG. 7B, the gauge surface 32 (FIG. 5) collapses and the front and rear end surfaces of the thin plate laminate 28 become flat. They are now arranged in a shape. Reference numeral 37 denotes a vibrator unit disposed downstream of the thin plate laminate 28 so as to face the thin plate laminate 28. As shown in FIG. 38, an inner holder 40 that can be slid in the longitudinal direction via a slide plate 39, an ultrasonic transducer 41 built into the inner holder 40, a wedge-shaped horn 42 attached to the outer holder 38, etc. It is constituted as a subject.

Further, 43 is a screw shaft rotationally driven by a pulse motor 44, 45 is a spline shaft also rotationally driven by a pulse motor 46, and the screw shaft 43 is attached to a nut 47 attached to the outer holder 38. They are screwed together, and as the screw shaft 43 rotates, the vibrator unit 37 moves horizontally along the screw shaft 43. On the other hand, the spline shaft 45 is
As shown in FIG. 8, it is splined to a pinion 49 attached to the outer holder 38 via a collar 48, and this pinion 49 is further screwed to a rack 50 attached to the inner holder 40. Therefore, the spline shaft 45 and pinion 4
9 prevents relative rotation between the two but allows relative movement in the axial direction, so the inner holder 40 is configured to be able to slide independently in a direction orthogonal to the spline shaft 45 by rotation of the spline shaft 45. It has been done. Note that 51 is a pulse generator integrated with the pulse motors 44 and 46. A ball screw consisting of the spline shaft 43 and the nut 47, pulse motors 44, 46, a spline shaft 45,
Vibrator unit 37 with rack 50, pinion 49, etc.
It constitutes a drive mechanism 52 for moving the. Next, the operation of the positioning jig with the above configuration will be explained.

First, the positioning jig of this embodiment is used for the workpiece w shown in FIGS. 3 and 5, as well as for the total 5 pieces shown in FIG.
Assuming that it is applied to the positioning of different types of panel workpieces W, Wl, W2, W3, and W4, the industrial robot 21
On the control device (not shown) side, each panel work W
, Wl, W2, W3, W4 in the X, Y, Z directions (
Figure 3) position information and each panel work W, Wl, W2
, W3, and W4 are stored in advance.

Now, suppose that the positioning of the panel work W1 shown in FIG. 9A is performed using the jig of this embodiment instead of the panel work shown in FIGS. 3 and 5, and the panel work W1 shown in FIG. When a work selection command signal for W, is applied, the actuator Ml of each industrial robot 21
, M2, and M3 move to the normal position for positioning the panel work W1 based on the above position information.

At the same time, as shown in FIG. 6B, the supply of working fluid to the cylinder 31, which had been in the stretched state and was pressurizing and clamping the thin plate stack 28, was cut off, and as a result, the thin plate stack 28 It becomes a non-pressurized state. Next, the cylinder 35 in the side plate 26 shown in FIG. 7A moves to extend, causing the rod 34 to retreat to its stroke diameter limit, thereby moving all the thin plates 28a including the substrate 29 to the position shown in FIG. 7B. Retreat all at once as shown. As a result, the shape of the gauge surface 32, which had been created on the other end surface side of the thin plate laminate 28, collapses, and the gauge surface 32, which is the other end surface, becomes flat. Next, of the three cylinders 31 shown in FIG. 6A, only the central cylinder 31 is operated to pressurize the entire thin plate stack 28 in the stacking direction, thereby performing temporary clamping.

After the vibrator unit 37 once returns to its original position in the Y and Z directions by the drive gate movement of the pulse motors 44 and 46, the pulse motors 44 and 4 are
Numerical information about the cross-sectional shape of the panel workpiece W1 is given to the transducer unit 6, and at the same time the transducer unit 37 is driven to oscillate, the transducer unit 37 is fed in the Y and Z directions. As a result, the tip of the horn 42 of the vibrator unit 37 hits the lower end surface of the thin plate laminate 28, and its excitation action pushes up each thin plate 28a constituting the thin plate laminate 28 by a predetermined amount. A gauge surface 32A (FIG. 10A) matching the cross-sectional shape of the panel work W1 is created on the upper end surface side. That is, the vibrator unit 37 is intermittently fed in the Y direction by one pitch corresponding to the thickness of one thin plate, and then similarly fed by a predetermined amount in the Z direction, and this operation is continued. By repeating this process, the gauge surface 32A is formed. In this case, as mentioned above, the thin plate stack 28 as a whole forms one cylinder 3.
1, but the clamper at this time is only used to preliminarily clamp the individual thin plates so that their positions do not shift. When excited, each thin plate moves easily. In this way, the gauge surface 32
When the creation of A is completed, the remaining two cylinders 31 extend and firmly clamp the thin plate laminate 28, on which the gauge surface 32 has already been completed, to make it even stronger as one gauge plate 32. 32 to position the panel work W1.

Of course, the workpiece W2 as shown in Fig. 10 B, C, and D
, W3, and W4, use the same method as above to position the gauge surface 32B that matches the cross-sectional shape of each workpiece.
, 32C, and 32D can be created. In this way, according to the jig of this embodiment, even if multiple types of panel workpieces have different cross-sectional shapes, numerical information corresponding to the cross-sectional shapes of those workpieces is given to the transducer unit, and each By changing the shape of the gauge surface, one welding jig can handle multiple workpieces.

In addition, because all the components of conventional jigs are fixed, it takes a lot of man-hours to correct or change the positioning accuracy of the jig itself, but this is true! According to the jig of the example, the position of the gauge unit can be easily changed by the robot's action, so by directly giving the correction amount as numerical information to the robot, it is possible to easily correct or change the positioning accuracy. And it can be done quickly.

FIG. 11 shows another more specific embodiment of the present invention, in which the gauge unit 23 described above is
This embodiment is applied to the positioning of the body side Wb of an automobile, which is a workpiece, by combining the robot 60 and an articulated robot 60, and in this embodiment, the effects of the previous embodiment are further enhanced.

In addition, the form of the robot in the first and second embodiments,
The number of axes, control method, etc. are not limited to those illustrated, and can be freely selected as necessary. In summary, according to the present invention, the gauge plate is composed of a thin plate laminate made up of a set of thin plates, and the shape of the gauge surface can be changed arbitrarily. It has excellent versatility because it can be applied to multiple types of workpieces, and the gauge surface can be changed easily and quickly.

[Brief explanation of the drawing]

Figure 1 is a perspective view showing the configuration of a conventional positioning jig;
FIG. 3 is a perspective view showing the configuration of another conventional positioning jig, FIG. 3 is an overall perspective view showing an embodiment of the positioning jig according to the present invention, and FIG. 4 is an enlarged explanatory view of only the gauge unit. Figure 5 is an enlarged view of only the gauge plate, Figure 6A,
B is a sectional view taken along the line ■-■ of each figure 4, and figures 7 A and B.
is an explanatory diagram of the operation of the gauge plate, FIG. 8 is a horizontal sectional view of the vibrator unit in FIG. 4, and FIG. 9 is A, B, C, D.
10A, B, C, and D are explanatory diagrams of the operation of the positioning jig, and FIGS. 9A, B, C, and D are perspective views showing the shape of the workpiece, and FIGS. 10A, B, C, D is Figure 9 A, B,
11 is a perspective view showing another embodiment of the present invention. 23... Gauge unit, 28a...
Thin plate, 28... Thin plate laminate, 30...
Gauge plate, 32, 32A, 32B, 32C, 32
D: Gauge surface, 37: Transducer unit, 41: Ultrasonic transducer, 43: Screw shaft, 45: Spline shaft , 49...Zenion, 50...Rack, 52
...Drive mechanism, W9Wl9W29W39W4...
...Panel work, 60...Tightening mechanism.

Claims (1)

[Claims] 1 In a jig for receiving and positioning a workpiece with a gauge plate formed with a gauge surface corresponding to the approximate cross-sectional shape of the workpiece, the gauge plate is composed of a thin plate laminate made by laminating a large number of strip-shaped thin plates. A vibrator unit is disposed at one end of the gauge plate so as to face it, and a drive mechanism for moving the vibrator unit in two-dimensional direction is provided, and the other end of the gauge plate A workpiece positioning jig characterized by having a tightening mechanism for holding an arbitrary gauge surface shape created on the side.