JPS6322017Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a workpiece positioning device for a workpiece assembly jig used primarily when assembling an automobile body.

As is well known, in an automobile body assembly device, in order to join a workpiece such as a cab side to an underbody or a header at a predetermined position, the workpiece is assembled to a workpiece assembly jig at a location away from the joining location, and then A method has been adopted in which a workpiece assembly jig is advanced to bring the workpiece into contact with an underbody and the like to join the workpiece (see, for example, Japanese Utility Model Application Publication No. 12817/1983).

As shown in FIGS. 3 and 4, the conventional workpiece assembly jig used in this case has a reference pin 2 for positioning the workpiece that protrudes in the horizontal direction at the upper end of a vertical jig frame 1. Further, a protrusion member 3 for positioning the workpiece was provided at the lower end thereof, and a workpiece support member 5 which was moved forward and backward by the cylinder 4 was provided at an intermediate portion between the two. On the other hand, as shown in FIG. 6, a reference hole H into which the reference pin 2 is inserted is formed in a workpiece W such as a cab side.
When assembling the workpiece W to the workpiece assembly jig, use a drip lid (not shown), etc.
As shown in FIG. 3, the workpiece W is placed on the workpiece support member 5, which is being advanced by the cylinder 4, via the frame portion F that becomes the window frame, and then,
By retracting the workpiece W together with the workpiece support member 5 to the jig frame 1 side by the cylinder 4, inserting the reference pin 2 into the reference hole H, and at the same time bringing the lower end of the workpiece W into contact with the protruding member 3. Work W
was being positioned.

In this case, as shown in FIG. 5, when the workpiece W is placed on the workpiece support member 5, the distance _l1 between the upper surface 5a of the workpiece support member and the center of the reference hole H may vary slightly ( several mm) different,
Moreover, since it is necessary for the workpiece assembly jig to have versatility for each vehicle type, the distance _l2 between the upper surface 5a of the workpiece support member and the axis of the reference pin 2 is set to the above-mentioned distance.
l is set to be slightly larger than ₁ . Therefore, when the workpiece W is positioned by inserting the reference pin 2 into the reference hole H as shown in FIG. be in a state of being In this state, the entire weight of the workpiece W is supported by the reference pin 2, so
A large load was placed on the upper edge of the reference hole H of the workpiece W that was in contact with the reference pin 2, causing the reference hole H to deform and making accurate positioning of the workpiece W impossible.

In addition, since the upper edge of the reference hole H comes into sliding contact with the reference pin 2 while the entire weight of the workpiece W is supported by the reference pin 2, the reference pin 2 is subject to wear as well as the deformation of the reference hole H described above. Easy to occur. Therefore, there has been a problem in that workpiece positioning accuracy tends to deteriorate early due to repeated use of the workpiece assembly jig.

This idea was created in view of the above circumstances, and is intended to prevent deformation of the reference hole during workpiece positioning, and to ensure long-term positioning accuracy by minimizing wear on the reference pin. The object of the present invention is to provide a workpiece positioning device for a workpiece assembly jig that can be used as a workpiece assembly jig.

In order to achieve the above object, in the present invention, a workpiece support member that supports a workpiece having a reference hole is held in a jig frame so as to be able to approach and separate from the jig frame in a substantially horizontal direction. A reference pin is protrudingly provided to be inserted into the reference hole of the workpiece when the workpiece support member approaches, and a tip of the reference pin is provided with a protruding reference pin that is inserted into the reference hole as the workpiece support member approaches. In a workpiece positioning device for a workpiece assembly jig, which is provided with a tapered guide portion that guides the workpiece so as to be inserted into the workpiece support member, the workpiece assembly jig is provided with a tapered guide portion that guides the workpiece so as to be inserted into the workpiece support member. a movably supported workpiece receiving section; an elastic body that constantly urges the workpiece receiving section upward with an elastic force capable of supporting the weight of the workpiece; and a stopper that restricts the workpiece receiving section from being raised above a predetermined position. It has a configuration that includes and.

Embodiments of this invention will be described below with reference to the drawings.

1 and 2, a workpiece receiving portion 6 is formed in a workpiece supporting member 5 fixed to the tip of a piston rod 4a of a cylinder 4. As shown in FIGS. That is, the workpiece receiving part 6 has its proximal end supported by the horizontal pin 7, and its intermediate part supported by the spring 8 interposed between it and the workpiece supporting member 5. The spring 8 always urges the workpiece receiving part 6 upward with an elastic force capable of supporting the weight of the workpiece W when the workpiece W is placed on the workpiece receiving part 6. In order to adjust the biasing force by the spring 8, one end of the spring 8 is attached to the workpiece support member 5.
It is held at the tip of an adjusting screw 9 that can be screwed in and out.

Further, a stopper 10 is provided on the workpiece support member 5 so as to project from the workpiece receiving portion 6 from above. This stopper 10 prevents the workpiece receiving part 6 from being flipped upwards by the biasing force of the spring 8 when no workpiece W is placed on the workpiece receiving part 6. That is, when the workpiece receiving part 6 is in contact with the stopper 10, the workpiece receiving part 6 is held at a predetermined position where the workpiece W can be placed. In addition, reference pin 2
A tapered guide portion 2a is formed at the tip of the guide portion 2a.

In the above configuration, when the workpiece W is placed on the workpiece receiving portion 6, the workpiece receiving portion 6 is moved from the position where it hits the stopper 10 (indicated by the imaginary line in the figure) to the spring 8, as shown in FIG. This downward load descends to a position (indicated by a solid line in the figure) where it is suspended by the urging force of the spring 8. In such a suspended state, the entire weight of the workpiece W is supported by the spring 8. In addition, in this state, with respect to the distance l ₁ between the upper surface 6a of the workpiece receiving part and the center of the reference hole H,
Distance between the upper surface 6a of the workpiece receiving part and the axis of the reference pin 2
l ₂ has the following relationship: l ₁ > l ₂ , l ₁ = l ₂ , or l ₁ < l ₂ .

For example, as shown in Fig. 1, when the distance l ₁ and l ₂ are such that l ₁ > l ₂ , the workpiece W is
When the workpiece W is retracted toward the jig frame 1 side, the lower edge of the reference hole H of the workpiece W hits the guide portion 2a of the reference pin 2, and the workpiece W is guided slightly downward against the biasing force of the spring 8. , is positioned by a reference pin 2 as shown in FIG. In this state, most of the weight of the workpiece W is supported by the spring 8 below the workpiece receiving part 6, and an extremely small load is applied to the lower edge of the reference hole H that contacts the reference pin 2. It's nothing more than that. Therefore,
The reference hole H will not be deformed, and the reference pin 2 will hardly wear out. The above intervals l ₁ and l ₂ are l ₁ < l ₂
The same is true for , but in this case, reference pin 2
The direction in which the workpiece W is guided by the guide portion 2a is upward. Also, when the above intervals l ₁ and l ₂ are l ₁ = l ₂ ,
No load is applied to the periphery of the reference hole H.

In addition, in FIGS. 1 and 2, the same components as those explained in FIGS. 3 to 6 are given the same reference numerals, and detailed explanations thereof are omitted for convenience.

In the above embodiment, the workpiece receiving part 6 was supported by the horizontal pin 7 to be movable up and down on the workpiece support member 5, but this point is different from the case where the workpiece receiving part 6 is movable up and down while being in a horizontal state. It may be supported by a workpiece support member so that Further, the mounting position of the spring 8 is not limited to the illustrated location. The same applies to the stopper pin 10.

As explained above, according to this invention, the workpiece receiving portion formed at the tip of the workpiece supporting member is
Since the workpiece is always urged upward by an elastic force capable of supporting the weight of the workpiece, when the workpiece is placed on the workpiece holder and the reference pin is inserted into the reference hole of the workpiece, the reference hole is Even if the workpiece is misaligned in the direction, almost the entire weight of the workpiece is supported by the elastic body, and only a very small load acts on the lower or upper edge of the reference pin or hole. . Therefore, the reference hole will not be deformed when assembling the workpiece to the workpiece assembly jig, wear on the reference pin will be minimized, and the accuracy of positioning the workpiece to the workpiece assembly jig will be maintained over a long period of time. guaranteed.

[Brief explanation of the drawing]

1 and 2 are partially cutaway front views showing how a work positioning device according to an embodiment of the invention is used; FIGS. 3 and 4 are overall front views showing how a conventional work positioning device is used; FIG. 5 is an explanatory diagram showing an enlarged main part of FIG. 3, and FIG. 6 is a schematic side view of the workpiece. 1... Jig frame, 2... Reference pin, 4...
Cylinder, 5... Work support member, 6... Work receiving part, 8... Spring, 10... Stopper, W
...Work, H...Reference hole.

Claims (1)

[Claims for Utility Model Registration] A workpiece support member that supports a workpiece having a reference hole is held in a jig frame so as to be able to approach and separate from the jig frame in a substantially horizontal direction, and the workpiece support member supports a workpiece having a reference hole. A reference pin is provided protrudingly to be inserted into the reference hole of the workpiece when the workpiece is approached, and a tip portion of the reference pin is configured such that the reference pin is inserted into the reference hole as the workpiece support member approaches the workpiece. In a workpiece positioning device for a workpiece assembly jig that is provided with a tapered guide portion that guides the workpiece, the workpiece assembly jig is provided with the workpiece support member and is supported movably in the vertical direction with respect to the workpiece support member. A workpiece receiving portion, an elastic body that constantly urges the workpiece receiving portion upward with an elastic force capable of supporting the weight of the workpiece, and a stopper that restricts the workpiece receiving portion from rising above a predetermined position. A workpiece positioning device for a workpiece assembly jig, characterized in that: