JP3337102B2 - Roller type hemming method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a roller-type hemming method which is used for hemming an edge of a panel material constituting, for example, an automobile body using a hemming roller.

[0002]

2. Description of the Related Art An engine hood W of an automobile shown in FIG.
Has an inner panel and an outer panel, and has a configuration in which both panels are integrated by performing hemming on the edge of the outer panel. In addition, a mold is sometimes used for hemming, but a roller-type device that bends a flange while moving along the edge of the panel is used. As this type of device, for example, a special device is used. Kaihei 5
There is one described in JP-A-305357. Note that the roller-type device is much smaller and has sufficient functions as compared with the mold, and has the advantages that the equipment cost and the like can be reduced.

In order to perform hemming using a hemming roller on the engine hood W, a pre-bending process is performed at the front edge A by bending the flange to a certain angle from the front left corner a to the front right corner b. (Indicated by the dotted line in the figure)
After that, the main bending (indicated by a solid line in the drawing) for completely bending the flange from the front right corner b to the front left corner a is performed. Since the engine hood W is mounted on the hem die with the inner panel facing upward, the left and right sides of the vehicle body are opposite to those in FIG. 3, but here the description will be made in accordance with the left and right sides in FIG. 3 for convenience. .

A left edge B between the rear left corner c and the front left corner a and a right edge C between the rear right corner d and the front right corner b are all rear corners c, The pre-bending and the main bending are performed from d to the front corners a and b, and the rear edge D between the rear corners c and d is performed such that the pre-bending and the main bending are in opposite directions.

[0005]

However, in the conventional roller-type hemming method as described above, when hemming the front edge A, for example, preliminary bending is performed from the front left corner a to the front right corner b. At this time, the flange portions (the portions X and Y in FIG. 3) of the left edge B near the front left corner a and the right edge C near the front right corner b tend to open outward. If hemming is performed on the left and right edges B and C in this state, parting meandering may occur. In addition, preliminary bending and bending in the same direction from the rear corners c and d toward the front corners a and b may be performed. When the main bending is performed, the rear corner portions c and d may be in a state of jumping up, and the surface accuracy may be reduced. Further, the front edge portion A has a bent portion (indicated by a symbol Z in FIG. 3). Surface bending or parting snakes Alternatively, since the flange may be turned, there is a problem that each time the pre-bending and the main bending are performed, the flange around the periphery must be corrected, and such a problem can be solved. It was an issue.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a roller-type hemming method capable of realizing a reduction in man-hours and a reduction in work time, and the like. And

[0007]

According to a roller type hemming method according to the present invention, in a hemming process performed on an edge portion of a panel material by using a hemming roller, one acute corner portion and the other are provided. When performing hemming on the edge between the corners, the pre-bending is performed toward one of the acute corners as a starting point toward the other corner, and then the middle of the edge as a starting point to each corner. The main bending is performed toward the main body, and the above configuration is used as means for solving the problem.

According to a second aspect of the present invention, there is provided a roller-type hemming method, wherein the panel member has a first edge having a bent portion, and acute corners opposed to the first edge and on both sides thereof. And a substantially rectangular shape having third and fourth edges on both sides of the first and second edges, and a second edge starting from the middle of the third edge. After preliminarily bending to the vicinity of the corner between the first edge and the fourth edge via the corner and the bent portion with the one edge, the first edge, the third edge, and the like starting from the bent portion The main bend is performed to the vicinity of the corner of the first edge and the corner of the first edge and the fourth edge, and then the second edge and the third edge are bent.
After preliminarily bending up to the corner between the third edge and the first edge starting from the sharp corner with the edge, the first edge and the second edge starting from the middle of the third edge And before and after this, pre-bending is performed before and after this, starting from the corner between the second edge and the fourth edge to the final bending end position of the first edge. The main bend is performed from the middle of the fourth edge to each corner with the first edge and the second edge, and further, the final bend end position of the first edge is used as the start point and After performing the main bending to the corner portion, and then performing the preliminary bending to the other corner portion with one corner portion of the fourth edge as a starting point,
The main bending is performed to one corner starting from the other corner, and the above configuration is used as a means for solving the problem.

Further, in the roller type hemming method according to the present invention, as a third aspect, the bent flange is formed into a shape in which the height is gradually reduced at the end of the edge, and the position where the reduction is started is determined by the edge. , The starting point and the ending point of the preliminary bending in the above, and the above-mentioned configuration is a means for solving the problem.

[0010]

According to the roller-type hemming method according to the first aspect of the present invention, the above-described structure can prevent the sharp corners from jumping and lowering the surface accuracy.

Further, in the roller type hemming method according to the second aspect of the present invention, by having the above-described structure, it is possible to prevent the occurrence of parting meandering near the corner, and
By preventing the occurrence of surface distortion, parting meandering or flange bending at the bent portion, the entire periphery of the panel material having the bent portion and the sharp corner portion is favorably hemmed, and the present invention is claimed. In the roller-type hemming method according to No. 3, the above-described configuration prevents molding defects more reliably.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a roller-type hemming method according to the present invention will be described below with reference to the drawings.

The panel material shown in FIG. 1A is an engine hood of an automobile, and the engine hood W is shown in FIG.
As shown in FIG. 2, the inner panel P1 and the outer panel P2 are provided, and the two panels P1 and P2 are integrated by bending (hemming) a flange F formed on an edge of the outer panel P2. Since the engine hood W is placed on the hem die with the inner panel P1 facing upward, the left and right sides of the vehicle body are reversed from those in FIG. 1A, but here, for convenience, FIG. The description will be made according to the left and right.

The engine hood W has a front edge portion.
A first edge portion) A and a rear edge portion facing the first edge portion (claim 4).
A second edge) D and a left edge (a third edge of claim 4) B
And a right edge (fourth edge of claim 4) C, a front edge A having a bent portion Z for slightly extending the central portion, and a sharp rear edge on both sides of the rear edge D. It has a left corner c and a rear right corner d. The front left corner a and the front right corner b have an angle slightly larger than 90 degrees.

The flange formed on the outer panel P2 is
As shown in FIG. 1B, the height of the edge is gradually reduced at the end.

FIGS. 2A to 2C are views for explaining the steps of the roller-type hemming process. The engine hood W is mounted on the hemmed die 5 with the inner panel P1 facing upward, as shown in FIG. A groove-shaped guide 26 for guiding rollers is formed on the hemmed die 5 along the edge of the engine hood W.

The hemming apparatus, in which the main body is omitted, is provided with upper and lower roller shafts 2 and 3 connected to a rotary drive source so as to be able to approach and separate from each other. A detachable pre-hem roller 40 and a hemm roller 4 are selectively attached, and a lower roller shaft 3 is provided with a pressing roller 6 that comes into contact with the lower surface of the hemmed die 5.

The prehem roller 40 has a tapered portion 40a that is tapered at the tip, and has a protruding engagement portion 27 with the guide 26 of the hem die 5 over the entire circumference. On the other hand, the hem roller 4 has the same circular cross section up to the tip, and also has a protruding engagement portion 27
Over the entire circumference.

In the hemming process, as shown in FIG. 2 (b), a prehem roller 40 is attached to the upper roller shaft 2, and the flange F is preliminarily bent by the tapered portion 40a. As shown, the hemming roller 4 is attached to the upper roller shaft 2 and the main bending is performed to completely bend the flange F.

To perform hemming on the engine hood W using the roller type hemming apparatus as described above,
First, preliminary bending (indicated by a dotted line in the drawing) is performed with the middle of the left edge B as the starting point 1 and the end point 2 near the front right corner b via the front left corner a and the bent part Z. In this way, the flange at the position X near the front left corner a of the left edge B does not open outward.

At this time, the start point 1 and the end point 2 are
At the end of the edge shown in (b), a position Q at which the height of the flange F starts to decrease is set. In the engine hood W of the vehicle, the position Q at which the height of the flange F starts to decrease is about 30 mm from the corner.

After the preliminary bending described above, the main bending (indicated by a solid line in the drawing) is performed from the bent portion Z as a starting point 3 to the front left corner a and the front right corner b. As a result, the bent portion Z is subjected to hemming without forming defects such as surface distortion, parting meandering, and flange bending. At this time, as shown in the enlarged view in FIG. 1A, two points 3a and 3b sandwiching the virtual vertex k of the bent portion Z are set, and the two points 3a and 3b are respectively set as starting points and directed in directions away from each other. If the final bending is performed, the bending of the flange F is not performed toward the outside of the panel material, so that the molding failure is more reliably prevented.

Next, a pre-bending is performed to the front left corner a with the rear left corner c, which is an acute corner, as the starting point 4, and then the middle of the left edge B is set as the starting point 5, and the front left corner a And final bending to the rear left corner c. As a result, hemming is performed at a position X near the front left corner a of the left side edge B without forming defects such as parting meandering.

Next, from the rear right corner d as a starting point 6, a preliminary bending is performed through the front right corner b to the hemming end position (2) of the front edge A, and then the middle of the right edge C is cut. As the starting point 7, the main bending is performed to the front right corner b and the rear right corner d, and further the main bending is performed from the hemming end position (2) of the front edge A to the front right corner b. As a result, hemming is performed at the position Y near the front right corner b of the right side edge C without forming defects such as parting meandering. The hemming of the right edge C may be performed before the hemming of the left edge B.

Finally, after preliminarily bending up to the rear left corner c with the rear right corner d as the starting point (6),
With the rear left corner c as the starting point (4), the main bending is performed to the rear right corner d, and all hemming processing is completed. As a result, the acute rear corners c and d are hemmed without forming defects such as jumping up and a decrease in surface accuracy.

In this way, the engine hood W is favorably hemmed over the entire circumference. In the hemming of the rear edge D, the starting points of the preliminary bending and the main bending may be reversed from those described above.

[0027]

【The invention's effect】

[0028]

According to the roller-type hemming method according to the first aspect of the present invention, when hemming is performed on the edge between one acute corner and the other acute corner, the edge jumps up to the acute rear corner. Hemming can be performed without causing molding defects such as deterioration of surface accuracy and the like, and since it is not necessary to correct the flange, it is possible to reduce man-hours and work time.

According to the roller-type hemming method according to the second aspect of the present invention, the first edge having the bent portion and the first edge are formed.
A substantially rectangular panel having a second edge facing the edge and having sharp corners on both sides thereof, and third and fourth edges on both sides of the first and second edges. When hemming a material, hemming is performed without causing molding defects such as parting meandering near the corners and without forming defects such as surface distortion or parting meandering or flange bending at the bent portion. Since it can be performed, hemming can be performed satisfactorily over the entire periphery of the panel material without causing molding defects, and is very suitable for, for example, hemming of an engine hood of an automobile. Time can be shortened.

According to the roller-type hemming method according to the third aspect of the present invention, the same effect as that of the second aspect can be obtained, and the height of the flange at the end of the edge portion starts to decrease. By setting the starting point and the end point of the pre-bending, it is possible to more reliably prevent molding defects in hemming using a roller-type hemming device, eliminating the need to correct the flange, reducing man-hours and reducing work Time can be shortened.

[0032]

[Brief description of the drawings]

FIG. 1 is a plan view (a) illustrating a case where a roller-type hemming method according to the present invention is applied to an engine hood of an automobile, together with an enlarged view near a bent portion, and a perspective view (b) of a corner portion of the engine hood. is there.

FIGS. 2A and 2B are cross-sectional views illustrating an engine hood positioning state (a), preliminary bending (b), and final bending (c) in a hemming process.

FIG. 3 is a plan view illustrating a process of hemming a conventional engine hood of an automobile.

[Explanation of symbols]

 A front edge (first edge) B left edge (third edge) C right edge (fourth edge) D rear edge (second edge) F flange W engine hood (panel material) Z Bending part a front left corner b front right corner c rear left corner (sharp corner) d rear right corner (sharp corner)

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B21D 39/02 B21D 19/04 B21D 19/08

Claims (3)

(57) [Claims] In a hemming process performed on an edge portion of a panel material using a hemming roller, one hem angle is formed when hemming is performed on an edge portion between one acute angle portion and the other acute angle portion. A roller type hemming method, comprising: performing preliminary bending toward the other corner side from a portion as a starting point, and then performing final bending toward each corner portion starting from the middle of the edge. 2. In a hemming process performed on an edge portion of a panel material using a hemming roller, the panel material includes a first edge portion having a bent portion and sharp corners opposed to the first edge portion and formed on both sides thereof. A substantially rectangular shape having a second edge having a portion and third and fourth edges on both sides of the first and second edges, with a middle point between the third edges as a starting point. After preliminarily bending near the corner between the first edge and the fourth edge through the corner with the first edge and the bend, the first edge and the third edge with the bend as the starting point The main bend is performed to the vicinity of the corner of the first edge and the corner of the first edge and the fourth edge, and then the third edge starting from the acute corner of the second edge and the third edge After performing preliminary bending to the corner between the portion and the first edge, while performing the main bending to each corner with the first edge and the second edge starting from the middle of the third edge, Before and after this, preliminary bending is performed to the final bending end point position of the first edge starting from the corner between the second edge and the fourth edge, and then the first bending is performed starting from the middle of the fourth edge. The main bending is performed to each corner with the edge and the second edge, and further, the main bending is performed to the corner with the fourth edge starting from the final bending end point position of the first edge. A roller-type hemming method, comprising: performing preliminary bending to one corner of one of four edges starting from the other corner, and then performing final bending to one corner using the other corner as a starting point. 3. The method according to claim 1, wherein the height of the flange to be bent is gradually reduced at the end of the edge, and the starting point of the reduction is defined as a start point and an end point of the pre-bending at the edge. 3. The method of hemming with a roller according to item 2.