JP7584964B2 - Roller hemming device - Google Patents

Description

The present invention relates to a roller hemming device, and in particular to a roller hemming device that places two panel members on top of each other on a lower die, presses the peripheral edge of the lower panel member with a bending roller, and folds it back onto the peripheral edge of the upper panel member to perform hemming.

In this type of roller hemming device, the first panel member and the second panel member are stacked in that order on top of a lower mold, and the peripheral edge of the first panel member, which has previously been bent upwards approximately vertically, is pressed toward the second panel member by the bending roller while the bending roller is moved, and the peripheral edge of the first panel member is folded back to envelop the peripheral edge of the second panel member, thereby performing hemming. For example, a pressing means such as a spring, an oil/pneumatic cylinder, or a servo motor is used to press with the bending roller.

In roller hemming used in the manufacture of mass-produced vehicle bodies, a bending roller is often attached to a manipulator of an industrial robot, as described in, for example, Patent Document 1 below. The industrial robot can freely move the manipulator within its movable range, and the bending roller attached to the manipulator can also be freely moved by so-called teaching. By freely using the bending roller in this way, a variety of hemming processes can be performed in a short time. Prior to the so-called main bending process, which is the stage in which the peripheral portion of the first panel member is pressed against the peripheral portion of the second panel member, a preliminary bending process is performed in which the peripheral portion of the first panel member is folded back toward the peripheral portion of the second panel member at a predetermined bending angle. In roller hemming devices using industrial robots, the preliminary bending process and the main bending process are often performed by a single device.

Japanese Patent Application Publication No. 5-305357

However, the body panel members that are hemmed are themselves becoming more diverse. The hemming areas of body panel members include areas where holes have been pre-drilled, the thickness of the panel members to be sandwiched is not uniform, or the members are not in contact with each other and there is a gap between the panel members. If normal hemming is performed in such areas, surface distortions may occur in the panel members, particularly the outer panel members of the body, after processing, which may reduce the appearance quality. Furthermore, hemming is generally difficult when fragile panel members such as resin are sandwiched between metal panel members.

The present invention was made in consideration of the above problems, and its purpose is to provide a roller hemming device that is less likely to cause surface distortion or other defects in the appearance quality of the panel member after hemming.

In order to achieve the above object, the roller hemming device of the present invention comprises:
A roller hemming device performs hemming by pressing and deforming a peripheral portion of the first panel member with a bending roller while placing a first panel member and a second panel member in this order on a lower mold and folding the first panel member toward the second panel member while moving the bending roller so that the peripheral portion of the first panel member wraps around the peripheral portion of the second panel member,
a hemming restriction mechanism having a restriction surface that is in contact with the bending roller during the hemming process to restrict an amount of pressing deformation caused by the bending roller ,
The hemming regulating mechanism includes a moving mechanism that moves the regulating surface to a retracted position where the regulating surface does not contact the bending roller.

With this configuration, the amount of deformation caused by the bending roller pressing against the peripheral edge of the first panel member is restricted at the location where the restricting surface of the hemming restricting mechanism comes into contact, i.e., the amount of deformation caused by pressing is suppressed, making it possible to suppress surface distortion and other problems at locations where a normal amount of deformation by pressing would cause such problems. Therefore, by providing a hemming restricting mechanism at a necessary location on the movement path of the bending roller and restricting the amount of deformation caused by pressing against the peripheral edge of the first panel member at that location, it is possible to reduce the occurrence of locations where the appearance quality is degraded, such as surface distortion.
In addition, in the preliminary bending process before the main bending process, the bending roller is positioned so that its pressing surface (outer peripheral surface) is inclined relative to the peripheral edge of the second panel member, so that the axial end of the bending roller protrudes downward from the peripheral edge of the first panel member, and this protruding portion may interfere with the restricting surface of the hemming restricting mechanism. In this way, if the bending roller and the hemming restricting mechanism interfere with each other during the preliminary bending process, the restricting surface can be moved to a retracted position by the moving mechanism, thereby avoiding interference between them.

Another configuration of the present invention is characterized in that the hemming control mechanism is provided at a position where the thickness of the peripheral portion of the second panel member changes when the peripheral portion of the first panel member is folded back, at a position where a hole is drilled in the peripheral portion of the second panel member, or at a position where a gap exists between the peripheral portion of the second panel member and the peripheral portion of the first panel member that encases it.

According to this configuration, by disposing a hemming restriction mechanism at any or all of the following locations on the peripheral portion of the second panel member where the peripheral portion of the first panel member is folded back: locations where surface distortions are likely to occur with normal hemming, locations where the thickness of the peripheral portion changes, locations where holes are drilled, and locations where gaps exist between the peripheral portion of the first panel member, it is possible to accurately reduce the occurrence of locations that degrade the appearance quality, such as surface distortions.

A further configuration of the present invention is that the hemming control mechanism is configured so that the contact position of the control surface with the bending roller can be adjusted using a shim.

With this configuration, the position of the regulating surface can be adjusted with a shim, allowing fine adjustment of the amount of pressure deformation of the peripheral edge of the first panel member, effectively reducing the occurrence of surface distortion, etc.

As described above, according to the present invention, by restricting the amount of pressure deformation of the peripheral edge of the panel member by the bending roller in areas where surface distortion is likely to occur during hemming, it is possible to reduce the occurrence of areas that degrade the appearance quality, such as surface distortion, thereby ensuring the marketability of the vehicle. It also becomes possible to perform hemming in which a fragile second panel member, such as a resin panel member, is wrapped in a first metal panel member.

1 is a front view showing a schematic configuration of an embodiment of a roller hemming device of the present invention; FIG. 2 is a front view of a hemming restriction mechanism provided in the roller hemming device of FIG. 1 . FIG. 3 is a detailed view of a main part of the hemming control mechanism of FIG. 2 . FIG.

An embodiment of the roller hemming device of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a front view showing the schematic configuration of the roller hemming device of this embodiment. In this embodiment, the roller hemming device places the first panel member 2 and the second panel member 3 in this order on the lower mold 1, and folds the peripheral portion 4 of the first panel member 2 (hereinafter, the first panel peripheral portion) 4, which has been folded in advance in a pre-process such as press molding substantially upward, i.e., substantially perpendicular to the plate surface, over the peripheral portion 5 of the second panel member 3 (hereinafter, the second panel peripheral portion) 5, and performs hemming so that the first panel peripheral portion 4 wraps around the second panel peripheral portion 5. Note that the figure is shown extremely diagrammatically, and the shapes of the actual lower mold 1, first panel member 2, and second panel member 3 are completely different. In addition, the first panel member 2 generally becomes the outer panel member of the vehicle body.

The hemming of the first panel peripheral portion 4 is performed by pressing with a bending roller 6. The bending roller 6 in this embodiment is a solid cylinder, and its outer circumferential surface is the pressing surface of the first panel peripheral portion 4. The bending roller 6 is rotatably supported by a manipulator 8 of a multi-axis industrial robot (hereinafter, robot) 7. As described above, the robot 7 can move the manipulator 8 to any position, direction, and orientation within the movable range, and therefore the bending roller 6 attached to the manipulator 8 can be moved to any position, direction, and orientation by so-called teaching. The operation of the robot 7 is controlled by a controller (not shown). The robot 7 itself may be mounted on a moving device so that it can move, for example, along the floor surface.

In this embodiment, the bending roller 6 is attached to the manipulator 8 of the robot 7 via a pressing device 9. In this embodiment, the bending roller 6 is configured to press the first panel peripheral portion 4 with a desired pressing force by a spring (not shown) provided in the pressing device 9. The hemming process in which the first panel peripheral portion 4 is bent onto the second panel peripheral portion 5 with this pressing force is defined as normal hemming. As mentioned above, for example, an oil/pneumatic cylinder or a servo motor can be used as the pressing means for pressing the bending roller 6.

Figure 2 is a diagram of the hemming restriction mechanism 10 provided in the roller hemming device of Figure 1, and the roller hemming device of this embodiment is provided with the hemming restriction mechanisms 10 shown in Figure 2 at multiple locations. Although the hemming restriction mechanisms 10 differ slightly depending on the locations at which they are provided, the general configuration is the same as that shown in Figure 2. This hemming restriction mechanism 10 restricts the amount of pressure deformation of the first panel peripheral portion 4 by the bending roller 6 when the bending roller 6 performs the main bending process of the hemming process by abutting the restriction surface 11 against the outer circumferential surface, i.e., the pressing surface. Therefore, the hemming restriction mechanism 10 (regulation surface 11) is arranged along the movement path of the bending roller 6 by the robot 7.

The hemming restriction mechanism 10 is provided at one or more locations, such as a location where holes have been drilled in advance in the second panel peripheral portion 5 where the first panel peripheral portion 4 is folded back, a location where the plate thickness of the second panel peripheral portion 5 changes, and a location where a gap exists between the first panel peripheral portion 4 and the second panel peripheral portion 5 after hemming. These locations are locations where surface distortions are likely to occur in the first panel member 2, i.e., the outer panel member of the vehicle body, during normal hemming. In addition, the hemming restriction mechanism 10 is also provided at a location where the first panel peripheral portion 4 (the second panel peripheral portion 5 has the same shape) itself is continuously curved within the panel member plate plane, which is also a location where surface distortions are likely to occur in the first panel member 2 after hemming.

Figure 3 is a detailed view of the main parts of the hemming control mechanism 10 in Figure 2. Figure 3 shows a location where a gap exists between the first panel peripheral portion 4 and the second panel peripheral portion 5 as an example of a location where the hemming control mechanism 10 is provided. The control member 12 that abuts against the outer peripheral surface of the bending roller 6 to form the control surface 11 is attached to the rotating support base 13 via a shim 14. In other words, the shim 14 placed under the control member 12 is interposed so as to be sandwiched between the rotating support base 13. This shim 14, like existing shims, is intended to fine-tune the position of the control surface 11 of the control member 12 by changing its own thickness, and there are several other shims of different thicknesses in addition to those shown in the figure. The height of the rotating support base 13 relative to the lower mold 1 is determined by a reference piece 15 provided on the lower mold 1 side (bracket 17) and an abutment piece 16 provided on the rotating support base 13 side so as to abut against its upper surface, but the height of the regulating surface 11 relative to the lower mold 1, i.e., the position of the regulating surface 11 that does not cause surface distortion in the first panel member 2, requires fine adjustment. Therefore, a shim 14 is interposed between the regulating member 12 and the rotating support base 13 so that the position of this regulating surface 11 can be adjusted with a shim.

The regulating member 12 (regulating surface 11) and the rotating support base 13 constituting the hemming regulating mechanism 10 are moved by the moving mechanism 21 to a retracted position where they do not come into contact with the bending roller 6, that is, so that they can be retracted from the movement path of the bending roller 6. The rotating support base 13 is rotatably attached to a bracket 17 provided on the lower die 1 below the movement path of the bending roller 6 via a rotating shaft 18 extending in a substantially horizontal direction. In addition, an air cylinder 19 that expands and contracts in a substantially vertical direction is attached to the bracket 17, and the tip of the cylinder rod 20 of the air cylinder 19 is rotatably connected to the opposite part of the rotating support base 13 across the rotating shaft 18. For example, the solid line in FIG. 2 shows a state in which the cylinder rod 20 is extended. When the cylinder rod 20 is shortened from this state, the rotating support base 13 rotates around the rotating shaft 18, and the rotating support base 13 and the regulating member 12 are moved to the position shown by the two-dot chain line in the figure. In other words, the regulating member 12 and the rotating support table 13 that constitute the hemming regulation mechanism 10 are retracted from the movement path of the bending roller 6.

In the roller hemming device of this embodiment, a preliminary bending process is performed on the first panel peripheral portion 4 prior to the main bending process. In the preliminary bending process, as shown in FIG. 4, the bending roller 6 is used at an angle so that the outer peripheral surface (pressing surface) of the bending roller 6 is inclined relative to the second panel peripheral portion 5, so that the axial end of the bending roller 6 protrudes downward from the first panel peripheral portion 4. Therefore, if the regulating member 12 (regulating surface 11) is present in the position shown in FIG. 3, for example, it will interfere with the downward protruding portion of the bending roller 6. Therefore, in this embodiment, the moving mechanism 21 provided in the hemming regulating mechanism 10 retracts the regulating member 12 (regulating surface 11) from the movement path of the bending roller 6, thereby moving the regulating surface 11 to a retracted position where it does not come into contact with the bending roller 6, thereby making it possible to avoid interference with the bending roller 6 during the preliminary bending process.

When holes are previously drilled in the second panel peripheral portion 5 where the first panel peripheral portion 4 is folded back by hemming, burrs and burrs around the holes are trapped, causing surface distortions in the first panel member 2 in normal hemming. In addition, when the thickness of the second panel peripheral portion 5 where the first panel peripheral portion 4 is folded back changes, for example, surface distortions occur in the first panel member 2 due to the first panel peripheral portion 4 being surplus on the side of the second panel peripheral portion 5 where the plate thickness is smaller. In addition, when there is a gap between the folded first panel peripheral portion 4 and the second panel peripheral portion 5, surface distortions occur in the first panel member 2 due to the elastic deformation of the first panel peripheral portion 4 before and after pressing. In addition, in areas where the first panel peripheral portion 4 and the second panel peripheral portion 5 are continuously curved within the plate surface, the folded first panel peripheral portion 4 becomes surplus, causing surface distortions in the first panel member 2. In this embodiment, normal hemming refers to a pressing process in which the first panel peripheral portion 4 is pressed onto the second panel peripheral portion 5 with a predetermined pressing force from the spring, which is the pressing means, as described above.

In such areas, the occurrence of surface distortions can be reduced by slightly reducing the amount of pressure deformation of the first panel peripheral portion 4 during the main bending process in the hemming process. Although the hemming process also has the significance of clamping the second panel peripheral portion 5 with the folded back first panel peripheral portion 4, it is not necessary to clamp the second panel member 3 at all peripheral portions. Therefore, even if the amount of pressure deformation of the first panel peripheral portion 4 is locally reduced in areas where surface distortions and the like are likely to occur as described above, it is unlikely that there will be any problems with clamping the second panel member 3, and rather, it is better to ensure marketability by eliminating areas that reduce the appearance quality, such as surface distortions, of the first panel member 2, which becomes the outer panel member.

An attempt was made to adjust the amount of deformation caused by pressure on the peripheral edge 4 of the first panel by teaching the robot 7. The manipulator 8 of the robot 7 can accurately trace the movement trajectory that has been taught, but due to the dimensional accuracy of the panel material produced by press molding in the previous process and the minuteness of the adjustment of the actual amount of deformation caused by pressure, it was not possible to reduce the occurrence of surface distortions by teaching the robot 7 alone.

In this way, in the roller hemming device of this embodiment, the amount of deformation caused by the bending roller 6 on the first panel peripheral portion 4 is restricted at the location where the restricting surface 11 of the hemming restricting mechanism 10 abuts, i.e., the amount of deformation caused by the pressing is suppressed, making it possible to suppress surface distortion and other problems at locations where normal amounts of deformation by pressing may occur. Therefore, by providing the hemming restricting mechanism 10 at a necessary location on the movement path of the bending roller 6 and restricting the amount of deformation caused by the pressing of the first panel peripheral portion 4 at that location, it is possible to reduce the occurrence of areas where the appearance quality is reduced, such as surface distortion. In addition, hemming processing is also possible in which a fragile second panel member 3, such as a resin panel member, is sandwiched between a metal first panel member 2.

In addition, in the second panel peripheral portion 5 where the first panel peripheral portion 4 is folded back, surface distortions are likely to occur in normal hemming at positions where the thickness of the peripheral portion 5 changes, where holes have been drilled, and where there is a gap between the first panel peripheral portion 4. Therefore, by providing a hemming restriction mechanism 10 at one or more of these positions, it is possible to reduce the occurrence of surface distortions and other areas that degrade the appearance quality.

In addition, if the bending roller 6 and the hemming control mechanism 10 interfere with each other during the preliminary bending process before the main bending process, the movement mechanism 21 can be used to move the control surface 11 to a retracted position to avoid interference between the two.

In addition, by making the position of the regulating surface 11 adjustable using the shim 14, the amount of pressure deformation of the first panel peripheral portion 4 can be fine-tuned, effectively reducing the occurrence of surface distortion, etc.

Although the roller hemming device according to the embodiment has been described above, the present invention is not limited to the configuration described in the above embodiment, and various modifications are possible within the scope of the gist of the present invention. For example, in the above embodiment, the regulating surface 11 of the hemming regulating mechanism 10 is configured to abut against the outer circumferential surface of the bending roller 6, i.e., the pressing surface of the bending roller 6, but the regulating surface 11 may abut against any part of the bending roller 6.

In the above embodiment, for example, during preliminary bending in hemming, the hemming restriction mechanism 10 is moved by the air cylinder 19 to a retracted position where the restriction surface 11 does not contact the bending roller 6, but the movement mechanism 21 is not limited to this. For example, since the bending roller 6 is moved together with the manipulator 8 of the robot 7, it is also possible to configure the hemming restriction mechanism 10 to be moved by the manipulator 8 to retract from the movement path of the bending roller 6 when the manipulator 8 approaches.

1 Lower die 2 First panel member 3 Second panel member 4 First panel peripheral portion (peripheral portion of first panel member)
5 Second panel peripheral portion (peripheral portion of second panel member)
6 bending roller 10 hemming restriction mechanism 11 restriction surface 14 shim 21 movement mechanism

Claims (3)

A roller hemming device performs hemming by pressing and deforming a peripheral portion of the first panel member with a bending roller while placing a first panel member and a second panel member in this order on a lower mold and folding the first panel member toward the second panel member while moving the bending roller so that the peripheral portion of the first panel member wraps around the peripheral portion of the second panel member,
a hemming restriction mechanism having a restriction surface that is in contact with the bending roller during the hemming process to restrict an amount of pressing deformation caused by the bending roller ,
The roller hemming device according to claim 1, wherein the hemming regulating mechanism includes a moving mechanism that moves the regulating surface to a retracted position where the regulating surface does not contact the bending roller . The roller hemming device according to claim 1, characterized in that the hemming control mechanism is provided at a position where the thickness of the peripheral portion of the second panel member changes when the peripheral portion of the first panel member is folded back, at a position where a hole is drilled in the peripheral portion of the second panel member, or at a position where a gap exists between the peripheral portion of the second panel member and the peripheral portion of the first panel member that encloses it. 3. The roller hemming device according to claim 1, wherein the hemming restriction mechanism is configured so that a contact position of the restriction surface with the bending roller can be adjusted by a shim.

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