JPH0323247B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a hemming method and an apparatus therefor. Furthermore, the present invention relates to a hemming method and an apparatus therefor, in which the tip end thereof can be folded forward so as to be parallel to the rearward folded portion.

[Prior Art] Hemming refers to the process of bending or folding the edges of parts. FIG. 4 shows a product manufactured using hemmed parts.

FIG. 4 is an external perspective view showing an example of a microwave oven. The microwave oven 1 consists of a main body 2 and a door 3. The main body 2 includes an inner box 4 and an outer frame 20. Inner box 4
As shown in the schematic perspective view of FIG. 5 and FIG. 6 (a sectional view taken along the - line in FIG. 5),
It is composed of a front plate 5, a body part 6, and a rear plate (not shown). A rear projecting portion 5a is provided at the periphery of the front plate 5 and extends toward the rear.

Next, a connection structure between the outer frame 20 and the inner box 4 will be explained. FIG. 7 is a sectional view of the connection structure between the outer frame 20 and the inner box 4.

The edge of the outer frame 20 has a double folded structure, with a first folded edge 2 folded back facing inward.
It includes a second folded part 21b formed by further folding the edges of 1a and the first folded part 21a inward. The outer frame 20 and the inner box 4 are connected by the front plate 5.
This is achieved by fitting the rear protrusion 5a provided around the periphery into the space formed by the first folded part 21a and the second folded part 21b. Such a connection is easier to operate than a connection made by welding or the like, and is applied not only to the above-mentioned microwave oven but also to other electrical products, mechanical products, etc. in a wide range of fields.

Next, a conventional hemming method for forming a double folded portion on the edge of a plate-shaped workpiece, which is applied to the outer box 20 and the like, will be described.

FIGS. 8A to 8G are cross-sectional views of conventional hemming processing. In particular, FIG. 8G shows a cross-sectional view of the final finished product.

Referring to FIG. 8G, the end of the plate-shaped workpiece 30 has a double folded structure, with a first folded part 31a folded inward and a first folded part 31a folded back. The second part is formed by further folding the edge.
The folded portion 31b is included.

Next, with reference to FIGS. 8A to 8F,
The steps leading to the final finished product shown in the figure will be explained.

With reference to FIG. 8A, the plate-shaped workpiece 30 is prepared, and then with reference to FIGS. 8B and 8G, the edge of the plate-shaped workpiece 30 is bent in the outward direction A, and the second The second folded part precursor 31 which becomes the folded part 31b of
form b′. At this time, the end portion of the second folded portion precursor 31b' is slightly bent in the forward direction B.

Next, referring to FIG. 8C, the second folded portion precursor 31b' is slightly tilted in the rear direction C.

Next, with reference to FIGS. 8C, 8D, and 8G, when the second folded portion precursor 31b' is further tilted rearward and brought close to the surface 30a of the plate-shaped workpiece, A second fold 31b is formed.

Next, with reference to FIGS. 8E and 8G for comparison, a portion of the edge of the plate-shaped workpiece 30 located further back is bent inward D to form a first folded portion 31a. 1 folded portion precursor 31a' is formed.

Next, referring to FIG. 8F, the first folded portion precursor 31a' is slightly tilted in the rearward direction C.

Next, referring to FIG. 8G, the first folded part precursor 31a' is further tilted in the backward direction C and brought close to the back surface 30b of the plate-shaped workpiece, and the first folded part 31a is formed. Ru.

[Problem to be Solved by the Invention] The conventional hemming process is configured as described above. For example, the steps shown in FIGS. 8A to 8E are performed with one device, and the steps shown in FIGS. 8F to 8G are performed. Processes have to be carried out using separate devices, making it impossible to complete processing with one processing device. As a result, operations have become complicated.

This invention was made to solve the above-mentioned problems, and in one process with one processing device,
The edge of the plate-shaped workpiece can be folded back, and the tip can be folded forward so that it is parallel to the folded back part, which facilitates processing operations. The object of the present invention is to provide a hemming method and device.

[Means for Solving the Problems] The present invention folds back the edge of a plate-shaped workpiece by a series of movements, and further folds the tip of the workpiece back.
Be parallel to the part folded back above,
This relates to a hemming device that folds back forward. The hemming device includes a first upper die and a first lower die that grip the main body of the plate-shaped workpiece with the edge portion of the plate-shaped workpiece protruding. a second upper bracket that grips the plate-shaped workpiece by sandwiching an edge of the plate-shaped workpiece at a position away from a gripping point of the main body-grip with respect to the plate-shaped workpiece; edge gripping means including a mold and a second lower mold; driving means for moving the edge gripping means in an arc around the gripping point; posture maintaining means for maintaining a constant gripping posture of the edge gripping means; connected to the first lower mold, the first lower mold is moved to the hemming processing position in the middle of the circular arc movement; a first lower mold moving means for moving the second upper mold to the rear so as to escape from the hemming position; and second upper mold moving means for moving the upper mold so as to release the mold.

Then, through a series of movements, the edge of the plate-shaped workpiece is folded back, and the tip is folded forward so that it is parallel to the folded back part. a step of gripping the main body of the plate-shaped workpiece by sandwiching it between a first upper mold and a first lower mold with the edge portion of the plate-shaped workpiece protruding; , at a position away from the gripping point where the plate-shaped workpiece is gripped, the edge of the plate-shaped workpiece,
a step of sandwiching and gripping between a second upper mold and a second lower mold; By moving the mold and the second lower mold in an arc,
a step of moving an edge of the plate-shaped workpiece in an arc around the gripping point, and in the middle of the arc movement, the second lower mold is placed below the first upper mold There is a method comprising the steps of: when the first lower die is turned around, the first lower die is moved backward from the hemming position, and the second upper die is moved forward from the hemming position.

[Operations and Effects of the Invention] In the hemming method and apparatus according to the present invention, the main body of the plate-shaped workpiece is sandwiched between the first upper mold and the first lower mold, and the edge of the plate-shaped workpiece is The end edges of the parts are sandwiched between a second upper mold and a second lower mold.

Next, while maintaining the gripping posture of the edge of the plate-shaped workpiece in a constant state, the second upper mold and the second lower mold are moved in an arc to center around the gripping point. The edge of the plate-shaped workpiece is moved in an arc.

When the edge gripping means consisting of the second upper mold and the second lower mold comes below the main body gripping means comprising the first upper mold and the first lower mold (the arc movement During the process), the first lower die is moved backward from the processing position, and the second upper die is moved forward from the processing position.

Next, at the end of the arc movement, the processed portion is sandwiched between the first upper mold and the second lower mold. This allows the first
A hemmed product having a shape in which the folded part and the second folded part are parallel to each other is obtained.

Since these steps are configured to be accomplished through a series of movements, the hemming process is completed in one step. As a result, only one processing device is required.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1H is a sectional view of the final finished product produced by the hemming process according to the present invention.

Referring to FIG. 1H, the end of the plate-shaped workpiece 30 has a double folded structure, and the edge of the plate-shaped workpiece is folded back (the first folded part 3
1a), and furthermore, the tip part is the first folded part 3
It is folded back forward so as to be parallel to 1a (second folded part 31b). Next, an apparatus and method according to the present invention for forming this double folded structure will be explained.

FIG. 1A is a conceptual diagram of an apparatus for realizing the hemming process according to the present invention. The device consists of a fixed part 14 and a moving part 15. In the figure, 30 is a plate-shaped workpiece. The fixing part 14 includes a main body gripping means 7 that grips the main body of the plate-like workpiece 30 with the edge portion 30c of the plate-like workpiece 30 protruding. The main body gripping means 7 includes a first lower mold 8 that supports the plate-shaped workpiece 30 from below, and a first upper mold 9 that presses the plate-shaped workpiece 30 from above.
A slope 8a is formed on the bottom surface of the first lower mold 8, and the shape of the slope 8a is selected so as not to impede the arc movement of the lower mold 12 shown in FIG.
The first upper mold 9 can be moved up and down by a cylinder 10 fixed to the device main body 40. The first lower mold 8 is movable by a cylinder 27 in the direction of piston movement.

The moving unit 15 is located at a position away from a gripping point 26 (a point where the protruding edge portion 30c is not moved) by the main body gripping means 7 on the plate-shaped workpiece 30. edge edge 3
It is provided with edge gripping means 11 for gripping 0d.
The edge gripping means 11 includes a second lower mold 12 that supports the edge 30d of the plate-shaped workpiece 30 from below, and a second upper mold 13 that presses the edge 30d from above. Predetermined molds are formed on the bottom surface 13a of the second upper mold 13 and the upper surface of the second lower mold 12. The shape of this mold is based on the bottom surface 1 of the second upper mold 13.
3a and the upper surface of the second lower mold 12, the edge edge 30
d, the second folded portion 31b (first H
(see figure) is chosen so that the shape is formed. Further, a slope 13 is also provided on the upper surface of the second upper mold 13.
b is formed. The shape and dimensions of the slope 13b are as follows:
It is selected so that the edge of the first folded portion 31a can be further folded inward (see Fig. 1H). The second upper mold 13 is moved up and down by a cylinder 16 rotatably attached to the moving part 15, and is moved up and down by a cylinder 17 rotatably attached to the moving part 15. , can move (including reciprocating motion) in the direction of arrow 18.

The moving part 15 is provided with a pin 19, and one end of the support member 21 is rotatably attached to the pin 19. The other end of the support member 21 is
It is connected and fixed to a pin 22 that rotates by the rotational force of a motor (not shown). The pin 22 is provided on a line passing through the gripping point 26 and perpendicular to the plane of the paper. The function of the support member 21 is as follows. That is, when the pin 22 rotates due to the rotation of the motor,
The support member 21 rotates around the pin 22.
When the support member 21 rotates, the pin 19 moves to the pin 22.
The movable member 15 moves in an arc around the center, and the moving member 15 also moves in an arc. That is, the support member 21
is a driving means for moving the edge gripping means 11 in an arc around the gripping point. A long hole 23 is provided along the arc movement of the pin 19.
This elongated hole 23 is not necessarily necessary if the support member 21 is made of a durable material.

On the moving member 15, at a position apart from the pin 19,
Another pin 24 is provided. and,
In order to guide the pin 24, an elongated hole 25, which is a parallel translation of the elongated hole 23, is provided in the device. The purpose of providing such a long hole 25 is to maintain the gripping posture of the edge gripping means 11 with respect to the plate-shaped workpiece 30 in a constant state when the moving member 15 moves in an arc. That is, pin 19,
The pin 24, the elongated hole 23, and the elongated hole 25 are posture maintaining means for maintaining the gripping posture of the edge gripping means 11 with respect to the plate-shaped workpiece 30 in a constant state during circular arc movement.

Next, with reference to FIGS. 1A to 1H, a method for forming a double folded portion at the edge of a plate-shaped workpiece using this hemming processing apparatus will be described.

Referring to FIG. 1A, the main body of the plate-shaped workpiece 30 is placed on the first lower mold 8, and the plate-shaped workpiece 30 is placed on the first lower mold 8.
0 edge edge 30d is placed on the second lower mold 12.

Next, referring to FIGS. 1A and 1B, the cylinder 10 is actuated to push down the first upper mold 9, and the main body of the plate-shaped workpiece 30 is combined with the first upper mold 9. Strongly pinch it with the first lower mold 8. on the other hand,
The cylinder 16 is operated to push down the second upper mold 13, and the edge 30d of the plate-shaped workpiece 30 is strongly sandwiched between the second upper mold 13 and the second lower mold 12. . At this time, the molds formed on the bottom surface of the second upper mold and the upper surface of the second lower mold form a second folded part 3 at the edge 30d of the plate-shaped workpiece.
1b (see FIG. 1H) is formed. This state is abbreviated in FIG. 1C. Figure 1C~
In Figure 1H, to simplify the drawing,
Only the movements of the mold are extracted and described.

Next, referring to FIG. 1D (also refer to FIG. 1B), drive the motor (not shown) to pin 2.
2 to rotate the support member 21 around the pin 22. Then, the pin 19 moves in an arc along the elongated hole 23, and the entire moving part 15 moves in an arc along the elongated hole 23. In turn, the edge gripping means 11
moves in an arc around the gripping point 26. During this arcuate movement, since the elongated holes 25 and 23 are provided in parallel, the gripping posture of the edge gripping means 11 with respect to the plate-shaped workpiece 30 is maintained in a constant state due to the action of the elongated holes 25. Ru.

Next, referring to FIGS. 1D and 1E, when the edge gripping means 11 is further moved in an arc, a state in which the edge gripping means 11 wraps around below the main body gripping means 7 is realized. At this time, the gripping point 26 of the main body gripping means 7 is located at the edge of the plate-shaped workpiece 30.
and the gripping point 33 of the edge gripping means 11 (see FIG. 1D).
The first lower mold 8 contacts the slope 13b formed on the top surface and the slope 8a formed on the bottom surface of the first lower mold 8.
A first folded part precursor 31a' which becomes the folded part 31a (see FIG. 1H) is formed. When this state is reached, Figure 1F (also refer to Figure 1B)
, the cylinder 17 is driven to move the second upper mold 13 in the direction of arrow 28, and at the same time, the cylinder 27 is driven to move the first lower mold 8 in the direction of arrow 29. Release these from the processing position.

Next, referring to FIG. 1G, when the arcuate movement of the second lower mold 12 is continued, the second lower mold 12
and the first upper mold 9 are opposed to each other, and the first folded portion precursor 31a is in contact with the back surface 30a of the plate-shaped workpiece 30.

Next, when the plate-shaped workpiece 30 is taken out from the apparatus,
As shown in FIG. 1H, the edge of the plate-shaped workpiece 30 is folded back, and the tip of the plate-shaped workpiece 30 is folded forward so that it is parallel to the folded back part. A processed portion is formed.

As described above, in this embodiment, the double folded portion can be formed by a series of seamless movements.
Processing operations become easier.

In the above embodiment, the first A is used as the means for moving the edge gripping means in an arc around the gripping point.
Referring to the figure, the motor (not shown) and the support member 2
1 and an elongated hole 23, the present invention is not limited thereto. Referring to FIG. 2 and FIG. 35 is attached and the moving part 15 is moved along the elongated hole 23 and the elongated hole 25 by the cylinder 35, the same effect as in the above embodiment can be achieved.

Further, in the above embodiment, the elongated hole 23 and the elongated hole 23 are used as posture maintaining means for maintaining the gripping posture of the edge gripping means 11 with respect to the plate-shaped workpiece in a constant state when the moving part 15 moves in an arc. The case where the hole 25 is provided is illustrated. However, the invention is not limited to this. That is, referring to FIG. 3, instead of providing a long hole, one end of the support members 21, 21' having the same length is rotatably attached to each of the pins 19 and 24 attached to the moving part 15. , the other end of the support members 21, 21' is connected to the pin 2
2 and 22', and these pins 22 and 22' are arranged so that the supporting members 21 and 21' are parallel to each other. Then, the pins 22, 22' are rotated at the same speed by a motor or the like, and the supporting members 21, 22' are rotated at the same speed.
21' is rotated at the same speed. Even with such a configuration, the same effects as in the embodiment can be achieved.

Although the present invention has been described above with reference to specific examples, the preferred examples described in this specification are illustrative and not restrictive. The scope of the invention is indicated by the claims,
All modifications that come within the meaning of the claims are intended to be included in the present invention.

[Brief explanation of the drawing]

FIG. 1A is a conceptual diagram of a hemming device for realizing the present invention. FIGS. 1B to 1H are shown using the hemming device shown in FIG. 1A.
FIG. 3 is a diagram showing a method for hemming a plate-shaped workpiece. FIG. 2 is a conceptual diagram of another embodiment of the hemming processing apparatus according to the present invention. Figure 3 shows
FIG. 7 is a conceptual diagram of still another embodiment of the hemming processing device according to the present invention. FIG. 4 is a perspective view of the microwave oven. FIG. 5 is a perspective view of the inner box of the microwave oven. FIG. 6 is a sectional view taken along the - line in FIG. 5. FIG. 7 is a sectional view of the connection structure between the outer frame and the inner box of the microwave oven. FIGS. 8A to 8G are cross-sectional views showing the conventional hemming process. In the figure, 7 is a main body gripping means, 8 is a first lower mold, 9 is a first upper mold, 11 is an edge gripping means, 12 is a second lower mold, and 13 is a second upper mold. Mold,
19 is a pin, 21 is a support member, 22 is a pin, 23
is a long hole, 26 is a gripping point, 30 is a plate-shaped workpiece, 3
0c is the edge portion, 31a is the first folded portion, 31b
is the second folded portion. In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] 1. Through a series of movements, the edge of the plate-shaped workpiece is folded back, and the tip thereof is folded forward so as to be parallel to the folded back part. The hemming device includes a first upper mold and a first lower mold that grip the main body of the plate-shaped workpiece in a state in which the edge portion of the plate-shaped workpiece is protruded. a second body gripping means including a mold; and a second body gripping means holding an edge of the plate-shaped workpiece at a position apart from a gripping point of the body gripping means on the plate-shaped workpiece. an edge gripping means including an upper mold and a second lower mold; a driving means for moving the edge gripping means in an arc around the gripping point; and during the arcuate movement, the plate-shaped workpiece posture maintaining means that maintains a constant gripping posture of the edge gripping means with respect to the object; and posture maintaining means that is connected to the first lower mold and that hems the first lower mold during the arcuate movement. a first lower mold moving means for moving the second upper mold backward from the hemming position; A hemming processing device comprising: a second upper mold moving means for moving the upper mold so as to release it forward. 2. A hemming method in which, through a series of movements, the edge of a plate-shaped workpiece is folded back and the tip thereof is folded forward so as to be parallel to the folded back part. , holding the main body of the plate-shaped workpiece by sandwiching it between a first upper mold and a second upper mold with the edge portion of the plate-shaped workpiece protruding; At a position away from the gripping point where the plate-shaped workpiece is gripped, the edge edge of the plate-shaped workpiece is
a step of gripping the plate-shaped workpiece with a second upper mold and a second lower mold; and a step of gripping the plate-shaped workpiece with the second upper mold while maintaining a gripping posture of the edge of the plate-shaped workpiece in a constant state. and by moving the second lower mold in an arc,
a step of moving an edge of the plate-shaped workpiece in an arc around the gripping point, and in the middle of the arc movement, the second lower mold is placed below the first upper mold; A hemming method comprising the steps of: when the first lower die is in a state where the hemming process is turned around, the first lower die is moved backward from the hemming position, and the second upper die is moved forward from the hemming position. .