JPH079040A - Hemming press device - Google Patents

Abstract

PURPOSE:To prevent defective forming and to improve workability for edge bending by edge bending by an upper die by compressing a work while changing its posture and rocking based on each rocking radius of first and second linkage plates. CONSTITUTION:In a hemming press device 1, the work 15 set on a lower die 4 is edge bent with one stroke moving of the upper die 10 supported on the base 2 side in a freely rocking state with the first and second linkage plates 7 and 8. The first linkage plate 7 is arranged near to the work 15 and the rocking raius of it is set shorter than the rocking radius of second linkage plate 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a material to be processed (work).
To an improvement of a hemming press device for edge-bending (hemming) the edges of the.

[0002]

2. Description of the Related Art Conventionally, a hemming device of Japanese Utility Model Laid-Open No. 57-176125 has been proposed as a technique for hemming the edge of a work. This is because the end edge of the work set in the lower die is moved by one stroke movement of the upper die supported by the frame through a pair of parallel links having the same swing radius.
Hemming is performed through preliminary bending and main bending.

[0003]

However, in the above-mentioned conventional technique, the upper die is supported on the frame through the parallel links having the same swing radius, and therefore the upper die is
The posture is not always changed by simply swinging with the same swing radius as each parallel link. Therefore, the upper mold does not necessarily press the optimum position of the edge with the optimum pressing force in each edge bending process, and it is easy for the defective work such as occurrence of reverse warp and deterioration of adhesion to the hemmed work. It was
Therefore, an object of the present invention is to provide a hemming press device that prevents defective molding and has good edge bending workability.

[0004]

SUMMARY OF THE INVENTION To achieve the above object, the present invention provides a one-stroke movement of an upper die swingably supported on a base side through a first link plate and a second link plate. In the hemming press device that performs edge bending of the work set in the lower die, the first link plate is arranged closer to the work, and the first link plate is set to have a swing radius shorter than that of the second link plate.

[0005]

The upper die swings while changing its posture based on the swinging radii of the first link plate and the second link plate. For this reason, the upper die oscillates gradually while bending forward with respect to the work, and in each edge bending process, the optimum position of the edge is pressed with the optimum pressing force to perform hemming.

[0006]

Embodiments of the present invention will be described below with reference to the accompanying drawings. The drawings should be viewed in the direction of the reference numerals.
FIG. 1 is a front view of a hemming press device according to the present invention. The hemming press device 1 fixes a lower mold frame 3 and an upper mold frame 6 on a base 2, and fixes a lower mold 4 on which a plate-shaped material (work) 15 is set on the lower mold frame 3. Then, the upper die 10 is swingably attached to the upper die frame 6 via the first link plate 7 and the second link plate 8. Reference numerals 9, 9, 11, and 11 are pins.

The first link plate 7 is arranged near the work 15, and the first link plate 7 has upper and lower pins 9,
The dimension L1 between 11 is set shorter than the dimension L2 between the upper and lower pins 9 and 11 of the second link plate 8. Therefore, the swing radius of the first link plate 7 is shorter than that of the second link plate 8.

The upper die 10 is swung in the directions of arrows AB by a driving means (not shown) such as a hydraulic device. Further, the upper die 10 has an arcuate pressing portion 10a on the side of the swing tip facing the work 15.

The operation of the hemming press device having the above structure will be described below. 2 (a) to 2 (c) are explanatory views of each edge bending process. FIG. 2 (a) shows that the upper end of the vertical edge 15a of the substantially L-shaped work 15 is pressed by the pressing portion 10.
The state where a has started pressing. When the upper die 10 swings in the direction of arrow A, the swinging radius of the first link plate 7 is shorter than that of the second link plate 8 (see FIG. 1), so that the pressing portion 10a gradually moves while bending forward, The upper end position S1 of the end edge 15a is pressed. At this time, the pressing force exerted on the position S1 by the pressing portion 10a is P, the operating angle is θ1, and the end edge 15a is pre-bent by the relatively large horizontal component force P1.

FIG. 2B shows a state where the edge 15a is being bent. The pressing portion 10a moves further in the direction of arrow A while bending forward, and presses the upper position S2 on the outer surface of the end edge 15a. At this time, the pressing force exerted by the pressing portion 10a on the position S2 is P, and the operating angle is θ2.
Further, a is further bent and is finally bent.

FIG. 2C shows a state in which the edge bending of the edge 15a is completed. The pressing portion 10a moves further in the direction of arrow A while bending forward, and presses the position S3 of the outer surface of the end edge 15a, which is close to the edge bending base end. At this time, the pressing force applied to the position S3 by the pressing portion 10a is P, and the operating angle is θ3.
The end edge 15a is bent by a vertical component force P2 larger than that in the state of FIG. 2B and FIG.

After that, the upper die 10 is returned to the position shown in FIG. 1 by a returning means (not shown). Therefore, in the hemming press device 1, the upper die 10 moves one stroke in the arrow A direction and the arrow B direction to perform pre-bending and main bending at one time, and hemming the edge 15a of the workpiece 15. it can.

As described above, as the pressing portion 10a moves in the direction of arrow A, the positions S1 to S for pressing the end edge 15a are pressed.
3 gradually moves to the vicinity of the bending base end of this edge, and correspondingly the working angle gradually increases from θ1 to θ3, and the horizontal component force P1 and the vertical component force P2 also change.
For this reason, the edge 15a is subjected to a large pressing force and hemmed at the most optimal position in each edging process, so that a good edging is performed.

Next, the finishing conditions of the work are compared between the hemming press device according to the present invention and the conventional parallel link type hemming press device. The results will be described. Figure 3
FIG. 4 is an explanatory diagram of a finished state after hemming, and compares the finished states by placing an intermediate plate on a work having an edge formed at a substantially right angle and performing hemming.

In the drawings, "Example" shows a finished state of a work hemmed by the hemming press device of the present invention,
“Comparative example” shows a finished state of a work hemmed by a conventional hemming press device having a parallel link. Regarding the finished state of the work, whether there is a warp (reverse warp) to the side opposite to the edge that has been bent, the edge of the edge bending, the presence of a bulge on the back side at the base end (bulge of the base end), the edge of the edge The amount of fold-in from the base end of bending (heme fold-in amount) and the degree of close contact (closeness of contact) between the edge after bending and the middle plate are compared.

According to this comparison result, the finish of the work hemmed by the hemming press device of the "Example" is as follows:
It can be seen that the reverse warp, the bulge of the base end, the amount of folded hem, and the degree of adhesion are all superior to the finish of the workpiece machined by the “comparative example” hemming press device.

[0017]

As described above, according to the present invention, the lower die is set by the one-stroke movement of the upper die swingably supported on the base side through the first link plate and the second link plate. In the hemming press device for performing edge bending of a work, the first link plate is arranged closer to the work, and the first link plate has a swing radius shorter than that of the second link plate. Is oscillated while changing its posture based on the oscillating radii of the first link plate and the second link plate, and presses the optimum position of the work edge with the optimum pressing force in each edge bending process to perform hemming. Therefore, defective molding can be prevented,
Good edge bending workability.

[Brief description of drawings]

FIG. 1 is a front view of a hemming press device according to the present invention.

FIG. 2 is an explanatory view of each edge bending process of the hemming press device according to the present invention.

FIG. 3 is an explanatory diagram of a finished state after hemming.

[Explanation of symbols]

1 ... Hemming press device, 2 ... Base, 3 ... Lower mold frame, 4 ... Lower mold, 6 ... Upper mold frame, 7 ... First link plate 7, 8 ... Second link plate, Pins 9, 10 ... Upper mold, 10a ... Pressing part, 11 ... pin, 15 ... work, 15
a ... edge.

Claims (1)

[Claims] 1. A hemming press for edge-bending a work set in a lower die by a one-stroke movement of an upper die swingably supported on a base side via a first link plate and a second link plate. In the apparatus, the first link plate is arranged closer to the work, and the swing radius of the first link plate is set shorter than that of the second link plate.