JP2014188568A - Hemming processing device and hemming processing method - Google Patents

Abstract

[PROBLEMS] To reliably perform prehem processing even when an upper die is lowered at high speed.
A lower die 200a, an upper die 200b that can be moved up and down, a prehem blade 221 that is provided on the lower die 200a and that can slide in a horizontal direction, a cam driver 223 provided on the upper die 200b, and a cam driver 223. And a cam mechanism that slides the pre-hem blade 221 toward the workpiece by pressing downward with the lower surface 223d of the cam driver 223 and the upper surface of the upper cam 225 of the cam mechanism 222. A flat surface in the horizontal direction was provided on 225a.
[Selection] Figure 6

Description

  The present invention relates to a hemming processing apparatus and a hemming processing method.

  Hemming is a processing method in which the periphery of the lower work is bent and integrated with the upper work disposed thereon, and is used, for example, when the inner panel and the outer panel of the door of the vehicle body are integrated.

  For example, Patent Document 1 shows a hemming apparatus 300 including a lower mold 301 and an upper mold 302 as shown in FIG. The lower die 301 is provided with a prehem processing unit 303, and the upper die 302 is provided with a main hem blade 308 and a cam driver 307. The cam driver 307 is provided with a cam 307a protruding in a mountain shape on the side. When the upper mold 302 is lowered, the cam 307a comes into contact with the pre-hem processing unit 303 {see FIG. 16A}. By continuing to lower the upper die 302 as it is, the pre-hem processing unit 303 is driven by the cam 307a, the pre-hem blade 304 moves to the lower die 301 side (left side in the figure), and presses the flange portion W1a of the lower workpiece W1 inward. Then, pre-hem processing is performed {see FIG. 16B}. Thereafter, when the upper die 302 is further lowered, the mountain-shaped cam 307a passes through the prehem processing unit, and the prehem blade 304 returns to the original position. At the same time, the main hem blade 308 presses and bends the flange portion W1a of the lower workpiece W1 from above and sandwiches the flange portion W2a of the upper workpiece W2, thereby performing the main hem processing {see FIG. 16C}. .

JP 2011-78992 A

  As described above, the prehem processing unit 303 is driven by the mountain-shaped cam 307a protruding laterally from the cam driver 307, so that the prehem blade 304 slides toward the workpiece (prehem processing) and the prehem blade 304 works. Separation from can be performed by a single descent of the upper mold 302. However, in this case, since the cam 307a and the roller of the pre-hem processing unit 303 come into contact with each other via an inclined surface (the inclined surface of the cam 307a) {see FIG. 16A}, the upper die 302 is intended to shorten the tact time. Is lowered at a high speed, the roller of the prehem mechanism 303 is repelled by the collision with the cam 307a, and there is a possibility that the prehem processing is not sufficiently performed.

  The technical problem to be solved by the present invention is to reliably perform the prehem processing even when the upper die is lowered at a high speed.

  In order to solve the above-mentioned problems, the present invention is capable of sliding in a direction in which the lower mold, the upper mold that can be moved up and down relative to the lower mold, and the workpiece set in the lower mold are approached and separated from the side A hemming processing apparatus comprising: a pre-hem blade, a cam driver provided in the upper mold, and a cam mechanism that slides the pre-hem blade toward a workpiece by pressing downward with the cam driver, Provided is a hemming processing device in which a horizontal flat surface is provided on the lower surface of the cam driver and the upper surface of the cam mechanism.

  As described above, the cam driver and the cam mechanism are brought into contact with each other between the flat surfaces in the horizontal direction, so that the pressing force of the cam driver can be reliably transmitted to the cam mechanism even when the upper die is lowered at a high speed. Therefore, pre-hem processing can be reliably performed on the workpiece.

  By the way, when the pre-hem processing is completed, it is necessary to separate the pre-hem blade from the workpiece to avoid interference between the main hem blade and the pre-hem blade in the subsequent main hem processing. As described above, when the cam driver and the prehem mechanism are in contact with each other on the flat surfaces in the horizontal direction, it is necessary to raise the upper die and the cam driver once in order to separate the prehem blade from the work after the prehem processing is completed. . If the cam driver and the pre-hem mechanism come into contact with each other during the subsequent real hem processing, the pre-hem blade may slide again toward the workpiece side, and the main hem blade and the pre-hem blade may interfere with each other. Therefore, when performing the actual hem processing, the upper die can be lowered only to a position where the cam driver and the pre-hem mechanism do not come into contact with each other, so that the mold operation during the actual hem processing is limited.

  Therefore, if the vertical distance between the lower surface of the cam driver and the upper surface of the cam mechanism that are opposed in the vertical direction can be changed while the upper die is stopped, hemming can be performed by the following procedure. That is, the upper die is lowered and the cam mechanism is pressed downward by the cam driver to slide the prehem blade to pre-hem the workpiece (see FIG. 7), and the upper die is raised. The step of separating the pre-hem blade from the workpiece and the step of increasing the vertical distance between the lower surface of the cam driver and the upper surface of the cam mechanism facing each other in the vertical direction with the upper die stopped (refer to FIG. 8) and a step (see FIG. 9) of lowering the upper die below the position where the pre-hem processing is performed (see FIG. 9).

  As described above, after the prehem processing, the upper die is once raised, and the distance between the cam driver and the cam mechanism is increased by increasing the vertical distance between the lower surface of the cam driver and the upper surface of the cam mechanism with the upper die stopped. The upper die can be lowered to a position lower than the position where the pre-hem processing has been performed without bringing the pre-hem into contact, that is, with the pre-hem blade retracted from the workpiece. Thereby, the freedom degree of metal mold | die operation | movement at the time of this hem processing can be raised.

  As described above, according to the hemming processing apparatus of the present invention, even when the upper mold is lowered at a high speed, the prehem processing can be reliably performed on the workpiece.

It is sectional drawing of a workpiece | work. It is the side view of a hemming processing apparatus, and the figure seen from the A direction of FIG. It is the side view of a hemming processing apparatus, and the figure seen from the B direction of FIG. It is a top view of the lower mold | type of a hemming processing apparatus. It is a bottom view of the upper model of a hemming processing device. It is sectional drawing of a hemming processing apparatus (just before prehem processing). It is sectional drawing of a hemming processing apparatus (at the time of prehem processing). It is sectional drawing of a hemming processing apparatus (after prehem processing). It is sectional drawing of a hemming processing apparatus (just before this hem processing). (A) is sectional drawing in the AA line of FIG. 7, (b) is sectional drawing in the BB line of FIG. It is sectional drawing of the locking mechanism of a hemming processing apparatus. It is sectional drawing of a hemming processing apparatus (just before this hem processing). It is sectional drawing of a hemming processing apparatus (at the time of this hem processing). It is sectional drawing of the hemming processing apparatus which concerns on other embodiment. It is sectional drawing of the hemming processing apparatus which concerns on other embodiment. It is sectional drawing which shows the process sequence by the conventional hemming apparatus, (a) is before prehem processing, (b) is the time of prehem processing, (c) shows the time of this hem processing.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  In this embodiment, the workpieces are the inner panel 1 and the outer panel 2 of the door of the automobile body (see FIG. 1), and the hemming method is integrated with the inner panel 1 by hemming the flange portion 2a of the outer panel 2. Show. This hemming processing method is performed using a hemming processing apparatus 200.

  The hemming apparatus 200 includes a pair of molds (a lower mold 200a and an upper mold 200b) that can approach and separate from each other, and a press machine that drives the pair of molds. As shown in FIGS. 2 and 3, the hemming apparatus 200 according to the present embodiment is provided in the base 201 and a press machine having a base 201, a ram 202, and first driving means 205 that drives the ram 202 up and down. A lower mold 200a and an upper mold 200b provided on the ram 202. The lower mold 200a and the upper mold 200b are general-purpose portions that differ depending on the shape of the workpiece, and can be attached to and detached from the base 201 and the ram 202, respectively.

  The base 201 has a first base 201a placed on the floor surface, a second base 201b disposed above the first base 201a, and a third base 208a disposed above the second base 201b. . The first base 201a has a substantially rectangular shape in plan view, and guide members 207 are erected at the four corners of the upper surface of the first base 201a. The second base 201b is a frame that has a substantially rectangular shape in plan view. A plurality of rails 201d extending in parallel are arranged on the upper surface of the second base 201b. The third base 208a is a plate material having a substantially rectangular shape, and has a hole in the center. The third base 208a is placed on the rail 201d and fixed to the second base 201b by fixing means (not shown).

  The lower mold 200a includes a movable base 208b and a work receiving portion 203 that functions as a lower mold. The movable base 208 b is disposed in a hole provided in the center of the third base 208 a and can be moved up and down with respect to the base 201. The movable base 208b is integrated into the hole of the third base 208a, thereby being integrated as a single plate 208. The movable base 208b is driven up and down by second driving means described later. Guides 208a are provided at the four corners of the movable base 208b, and guide receivers 201e are provided at the third base 208a. As the guide 208a and the guide receiver 201e slide, the up and down of the movable base 208b with respect to the third base 208a is guided.

  The lower mold 200a is slidable with respect to the base 201 along the rail 201d. When exchanging the forming die (work receiving portion 203 in this embodiment) or the like, the fixing means (not shown) for fixing the second base 201b and the third base 208a is released, and the lower die 200a and the third base are released. 208a is removed from the base 201 by sliding it on the rail 201d in the vertical direction of FIG. Then, after replacing the workpiece receiving portion 203 and the like on the movable base 208b, the lower mold 200a is slid in the vertical direction in FIG. 4 on the rail 201d and arranged at a predetermined position on the base 201, and the second base 201b and The third base 208a is fixed by fixing means (not shown).

  The work receiving part 203 is fixed to the upper surface of the movable base 208b. The workpiece receiving portion 203 supports the workpiece from below. In the illustrated example, the workpiece receiving portion 203 includes an annular portion 203a and a plurality of auxiliary portions 203b provided inside the annular portion 203a. The annular portion 203a is provided at a position that supports the peripheral portions (flange portions 1a, 2a) of the inner panel 1 and the outer panel 2 from below. The annular portion 203a functions as a mold that presses the workpiece in cooperation with the main hem blade 204 provided in the upper mold 200b. The upper surfaces of the annular portion 203a and the auxiliary portion 203b are formed following the shape of the outer panel 2. In the illustrated example, for the sake of simplicity, the upper surface of the outer panel 2 and the work receiving portion 203 that presses the outer panel 2 and the lower surface of the main hem blade 204 are shown as flat surfaces. However, these surfaces are actually curved surfaces. .

  The second driving means 206 drives the lower mold 200a up and down relative to the base 201. The second drive means 206 has a larger output than the first drive means 205, and in this embodiment is constituted by a hydraulic cylinder 206a and a servo motor 206b for driving the hydraulic cylinder 206a (see FIG. 2). The second driving means 206 is accommodated in a space between the first base 201a and the movable base 208b. The main body of the hydraulic cylinder 206a is fixed to the first base 201a. The upper end of the pin 206a1 of the hydraulic cylinder 206a is disposed below the movable base 208b via a gap. The movable base 208b is pushed up at the upper end of the pin 206a1 by driving the hydraulic cylinder 206a to raise the pin 206a1. The second driving means 206 is provided at a plurality of locations, for example, and is provided at four locations in the present embodiment (see FIG. 4).

  The ram 202 is slidable with respect to the base 201 in the direction in which the mold is closed, and can be raised and lowered in the present embodiment. As shown in FIG. 5, the ram 202 has a substantially rectangular shape in plan view, and is provided with guide holes 202a through which the guide members 207 are inserted at the four corners. The guide member 207 is a bar-like member extending in the vertical direction, and guides the ascending and descending of the ram 202 by sliding with the guide hole 202a. The upper ends of the guide members 207 are connected by a connecting member 207a extending in the horizontal direction (see FIG. 2). The guide members 207 are not necessarily provided at the four corners, and may be provided only at two diagonal positions, for example.

  The upper mold 200b includes a plate 209 fixed to the ram 202 and a main hem blade 204 that functions as an upper mold. The plate 209 is detachably fixed to the central portion of the lower surface of the ram 202. The main hem blade 204 performs the main hem processing and is fixed to the lower surface of the plate 209. The hem blade 204 is provided in an annular shape along the periphery of the outer panel 2 and faces the annular portion 203a of the workpiece receiving portion 203 in the vertical direction.

  The first driving means 205 moves up and down the ram 202 and the upper mold 200b, and a driving speed higher than that of the second driving means 206 is used. The first drive means 205 of the present embodiment includes a chain and a motor that drives the chain. Specifically, as shown in FIG. 3, a pair of chains 205a and a motor 205b that drives the pair of chains 205a And a pair of storage boxes 205c for storing the chains 205a. A pair of chains 205a supplied from each storage box 205c mesh with each other between the storage boxes 205c to form a single vertical bar portion 205d, and a ram 202 is attached to the upper end of the bar portion 205d. By rotating the motor 205b in the direction of the arrow in FIG. 3, each chain 205a is supplied from the storage box 205c to the rod-shaped portion 205d, and the rod-shaped portion 205d extends upward, thereby raising the upper mold 200b. On the other hand, by rotating the motor 205b in the direction opposite to the above, each chain 205a is returned from the rod-shaped portion 205d to the storage box 205c, and the rod-shaped portion is lowered while being contracted, whereby the upper mold 200b is lowered.

  The hemming apparatus 200 is provided with a prehem mechanism 220. As shown in FIG. 6, the prehem mechanism 220 of the present embodiment includes a prehem blade 221 and a cam mechanism 222 provided on the lower mold 200a side (on the plate 208), and a cam driver 223 provided on the upper mold 200b. Become. As shown in FIG. 4, the pre-hem blade 221 is provided around the workpiece receiving portion 203, and is slidable in a direction in which the workpiece moves toward and away from the workpiece in the horizontal direction. In the illustrated example, a prehem blade 221 is provided along each side of a substantially rectangular base 201 (third base 208 a), and each prehem blade 221 is slidable in a direction orthogonal to each side of the base 201.

  The cam mechanism 222 converts the push-down force caused by the lowering of the upper mold 200b into a force that slides the pre-hem blade 221 toward the workpiece. The cam mechanism 222 of this embodiment includes a lower cam 224 fixed to a plate 208 (third base 208 a in the illustrated example), and an upper cam 225 that slides along the lower cam 224. A flat surface in the horizontal direction is provided on the upper surface 225a of the upper cam 225. On the lower surface of the upper cam 225 and the upper surface of the lower cam 224, parallel and flat inclined surfaces 225b and 224a that are inclined inward (workpiece side) are provided. The upper cam 225 is slidable along the inclined surface 224 a of the lower cam 224. A prehem blade 221 is fixed to the side surface of the upper cam 225 on the workpiece side.

  The cam mechanism 222 is provided with a stopper 226 that restricts the movement of the prehem blade 221 on the side close to the workpiece at a predetermined position. In the illustrated example, a stopper 226 is provided at the lower end of the inclined surface 224a of the lower cam 224 to restrict the upper cam 225 from sliding obliquely downward. The cam mechanism 222 is provided with a biasing means 227 that biases the upper cam 225 and the pre-hem blade 221 toward the side away from the workpiece (the right side in FIG. 6). In the illustrated example, the urging means 227 is constituted by an air cylinder, and the upper cam 225 and the pre-hem blade 221 are always urged to the side away from the workpiece.

  The cam driver 223 includes a main body part 223a fixed to the plate 209 of the upper mold 200b, and a movable part 223b provided at the lower end of the main body part 223a. The movable portion 223b is movable between a position where it abuts on the cam mechanism 222 and a position where it does not contact the cam mechanism 222. In the illustrated example, the movable part 223b can be rotated around the pin 223c by a driving part (not shown). A flat surface in the horizontal direction is provided on the lower surfaces of the main body 223a and the movable portion 223b.

  One of the lower surface 223d of the movable portion 223b of the cam driver 223 and the upper surface 225a of the upper cam 225 that slide with each other is provided with a guide groove extending in the sliding direction (left-right direction in FIG. 6), and the other in the sliding direction. Protrusions extending in the direction are provided. In this embodiment, as shown in FIG. 10A, a protrusion 223d1 extending in the sliding direction is provided on the lower surface 223d of the movable portion 223b of the cam driver 223, and the upper surface 225a of the upper cam 225 is provided in the sliding direction. An extending guide groove 225a1 is provided. In addition, a guide groove extending in the sliding direction (the extending direction of the inclined surfaces 225b and 224a in FIG. 6) is provided on one of the inclined surface 225b of the upper cam 225 and the inclined surface 224a of the lower cam 224 that slide relative to each other. The other is provided with a protrusion extending in the sliding direction. In this embodiment, as shown in FIG. 10B, the inclined surface 225b of the upper cam 225 is provided with a protrusion 225b1 extending in the sliding direction, and the inclined surface 224a of the lower cam 224 extends in the sliding direction. A guide groove 224a1 is provided.

  The hemming processing apparatus 200 includes a lock mechanism 230 that connects the base 201 and the ram 202 to restrict the ascent of the ram 202. The lock mechanism 230 is provided in the vicinity of each corner of the rectangular base 201 and the ram 202. As shown in FIGS. 6 and 7, the lock mechanism 230 moves the upper lock member 231 provided in the ram 202, the lower lock member 232 provided in the base 201, and both lock members 231 and 232 in the vertical direction. And locking means 233 for locking. In the present embodiment, as shown in FIG. 16, horizontal through holes 231 a and 232 a are formed in both lock members 231 and 232. Each of the through holes 231a and 232a has a cylindrical inner peripheral surface having the same diameter. In the illustrated example, in each lock mechanism 230, a lower lock member 232 is provided on both sides of the upper lock member 231. A protrusion 231b that protrudes in the horizontal direction is provided at the upper end of the upper lock member 231, and the upper lock member 231 is attached to the ram 202 in a suspended state by bringing the protrusion 231b into contact with the ram 202 from above. . The lower lock member 232 is fixed to the upper surface of the third base 208a.

  The engaging means 233 regulates the relative vertical movement (particularly movement in the mold opening direction) by engaging both the lock members 231 and 232 in the vertical direction. In the present embodiment, the locking means 233 includes a locking pin 233a and a driving unit 233b (for example, an electric cylinder or an air cylinder) that moves the locking pin 233a back and forth in the horizontal direction. The locking pin 233a has a cylindrical outer peripheral surface, and in the present embodiment, forms a solid columnar shape. The outer diameter of the locking pin 233a is slightly smaller than the inner diameter of the through holes 231a, 232a of the first and second lock members 231, 232. As shown in FIGS. 8 and 9, the axial center direction P of each locking pin 233a and the through holes 231a and 232a is the same as the locking pin 233a and the center O of the ram 202 (substantially coincident with the center of the base 201). It is substantially orthogonal to the connecting straight line L (in this embodiment, diagonal lines at the corners of the base 201 and the ram 202).

  Hereinafter, the procedure of the hemming method according to the present embodiment will be described.

  First, after supplying the sealer S to the inner side of the flange portion 2a of the outer panel 2, the inner panel 1 is placed on the sealer S in an overlapping manner. The outer panel 1 and the inner panel 2 are carried into the hemming apparatus 200 and set on the work receiving portion 203. In this state, the first driving means 205 is driven to lower the upper die 200b from the upper end position, thereby pre-heming the workpiece. At this time, as shown in FIG. 6, the cam driver 223 is in a state in which the vertical distance between the lower surface 223d and the upper surface of the cam mechanism 222 (the upper surface 225a of the upper cam 225) is reduced. Specifically, the movable portion 223b of the cam driver 223 is in a state of being disposed at a position where it can contact the cam mechanism 222 (below the main body portion 223a). By lowering the upper die 200b in this state, the cam driver 223 provided on the upper die 200b abuts from above the upper cam 225 of the cam mechanism 222 (see the dotted line in FIG. 6). At this time, the lower surface 223d of the cam driver 223 and the upper surface 225a of the upper cam 225 are brought into contact with each other with the flat surfaces in the horizontal direction, so that the upper cam 225 is surely pushed down even when the upper die 200b is lowered at high speed. Can do.

  By continuing to lower the upper die 200b as it is, the cam driver 223 presses the upper cam 225 downward, and the upper cam 225 and the pre-hem blade 221 slide inward (work side) along the inclined surface 224a of the lower cam 224. (See FIG. 7). At this time, the inclined surface 224a of the lower cam 224 and the inclined surface 225b of the upper cam 225 are brought into surface contact with each other, so that the upper die 200b is lowered at a high speed and the lower cam 224 collides with the cam driver 223. Even when an impact is applied, the pre-hem blade 221 can be reliably slid inward by sliding the upper cam 225 obliquely downward along the inclined surface 224a. Further, a protrusion 223d1 on the lower surface 223d of the cam driver 223 and a guide groove 225a1 on the upper surface 225a of the upper cam 225, and a protrusion 225b1 on the inclined surface 225b of the upper cam 225 and a guide groove 224a1 on the inclined surface 224a of the lower cam 224, respectively. By fitting (see FIG. 10), the sliding direction of the upper cam 225 is guided. Thus, the flange portion 2a of the outer panel 2 is bent inward by the pre-hem blade 221 and pre-hem processing is performed. Note that the hem blade 204 does not contact the workpiece (particularly the flange portion 2a of the outer panel 2) during the pre-hem processing.

  When the prehem processing is completed, the upper die 200b is once raised by the first driving means 205 (see FIG. 8). At this time, the upper cam 225 and the prehem blade 221 are moved away from the workpiece by the biasing force of the biasing means 227 of the prehem mechanism 222 and returned to the initial position. Then, with the upper mold 200b stopped, the vertical distance between the lower surface 223d of the cam driver 223 and the upper surface of the cam mechanism 222 (the upper surface 225a of the upper cam 225) is increased. Specifically, the movable portion 223b of the cam driver 223 is rotated about the pin 223c, and the movable portion 223b is retracted to a position where it does not contact the cam mechanism 222 (side of the main body portion 223a). Thus, the vertical distance H2 between the lower surface 223d of the cam driver 223 (the lower surface of the main body 223a) and the upper surface 225a of the upper cam 225 of the cam mechanism 222 is the vertical direction before the movable portion 223b is rotated. It becomes larger than the distance H1 (H2> H1). Note that the rotation direction of the movable portion 223b is not limited to the direction away from the workpiece as shown in the figure, and may be retracted in, for example, a direction along the side of the plate portion 208 (a direction orthogonal to the paper surface of FIG. 8). In this state, the upper die 200b is lowered again by the first driving means 205, and when the main hem blade 204 is disposed immediately above the flange portion 2a of the outer panel 2, the upper die 200b is stopped (see FIG. 9). At this time, the cam driver 223 and the upper cam 225 are not in contact with each other, and the pre-hem blade 221 is held at a position retracted from the workpiece (specifically, a position retracted from the vertical direction between the main hem blade 204 and the workpiece receiving portion 203). The

  Thus, after pre-hem processing is performed, the upper die 200b can be lowered below the pre-hem processing completion position (see FIG. 7) by increasing the vertical distance between the cam driver 223 and the cam mechanism 222. Yes (see FIG. 9). Thereby, the rising stroke of the workpiece receiving part 203 and the movable base 208 in the main hem processing described later can be reduced.

  When the upper die 200b is stopped as described above and the hem blade 204 is disposed directly above the flange portion 2a of the outer panel 2, as shown in FIG. 11, the upper lock member 231 constituting the lock mechanism 230 is locked to the lower lock. When inserted between the members 232 and the lower end of the upper lock member 231 contacts the lower lock member 232, the through holes 231a and 232a of the lock members 231 and 232 are concentrically arranged. In this state, the base 201 and the ram 202 are connected by the lock mechanism 230. In the present embodiment, the driving portion 233b of the locking means 233 is driven to advance the locking pin 233a, and the locking pin 233a is inserted into the through holes 231a and 232a of both lock members 231 and 232 (see FIG. 11). (See dotted line). Thus, when the locking pin 233a engages with the lock members 231 and 232 in the vertical direction, the relative vertical movement of the base 201 and the ram 202 (in this embodiment, the ram 202 is lifted) is restricted.

  With the base 201 and the ram 202 thus connected by the lock mechanism 230, this hem processing is performed on the flange portion 2 a of the outer panel 2. Specifically, as shown in FIGS. 12 and 13, the lower mold 200 a is pushed up by the second driving means 206 in a state where the base 201 and the ram 202 are connected by the lock mechanism 230. Thereby, in a state where the base 201, the lock mechanism 230, the ram 202, and the main hem blade 204 are fixed, the movable base 208b, the work receiving portion 203, and the work (the inner panel 1 and the outer panel 2) are raised, and the prehem processing is performed. The flange portion 2a of the applied outer panel 2 is pressed against the main hem blade 204 from below, and the flange portion 2a is further bent. At this time, servos connected to the respective hydraulic cylinders 206a so that the protruding amounts of the pins 206a1 of a plurality (four in the illustrated example) of the hydraulic cylinders 206a become equal, that is, the movable base 208b rises in a horizontal state. The motor 206b is controlled. When the pressure in the hydraulic cylinder 206a of the second driving means 206 reaches a predetermined value, the servo motor 206b is stopped. At this time, the predetermined value of the pressure for stopping each hydraulic cylinder 206a is set to a value corresponding to each part. By the above, the flange part 2a of the outer panel 2 is completely bent, and this hem processing is completed. In FIGS. 12 and 13, the second base 201b and the rail 201d are omitted for convenience.

  The present invention is not limited to the above embodiment. For example, the workpiece is not limited to the inner panel 1 and the outer panel 2 of the door of the vehicle body, and may be, for example, the hood of the vehicle body or the inner panel and the outer panel of the back door.

  In the embodiment shown in FIG. 14, the vertical dimension of the movable portion 223b of the cam driver 223 is larger than that in the above embodiment. By retracting the movable portion 223b to the side of the main body 223a, the vertical distance between the lower surface of the cam driver 223 and the upper surface 225a of the upper cam 225 of the cam mechanism 222 can be greatly increased. By lowering the upper die 200b in the subsequent main hem processing, the main hem processing can be performed on the flange portion 2a of the outer panel 2 with the main hem blade 204 in a state where the cam driver 223 and the cam mechanism 222 are not brought into contact with each other. (See dotted line in FIG. 14). In this case, since it is not necessary to raise the workpiece receiving portion 203, the movable base 208b can be omitted and the plate 208 can be integrated.

  In the embodiment shown in FIG. 15, the cam driver 223 is an integrated product having no movable part. In this embodiment, after the prehem processing is completed, the upper die 200b is raised until the prehem blade 221 is retracted from between the main hem blade 204 and the work receiving portion 203. In this state, the base 201 and the ram 202 are locked and the work receiving portion 203 and the movable base 208 are raised, so that the main hem blade 204 and the work receiving portion 203 perform the main hem processing on the flange portion 2a of the outer panel 2. (See dotted line in FIG. 15). In this case, the step of raising the upper die 200b once after the completion of the prehem machining and then lowering the upper die 200b again can be omitted, while the raising stroke of the workpiece receiving portion 203 during the hemming is more than that in the above embodiment. become longer. Therefore, when it is desired to shorten the rising stroke of the workpiece receiving portion 203, the above embodiment (see FIGS. 6 to 13) may be employed.

  In the above embodiment, the cam driver 223 is provided with the movable portion 223b, so that the vertical distance between the lower surface 223d of the cam driver 223 and the upper surface 225a of the cam mechanism 222 that are opposed in the vertical direction can be changed. However, the distance in the vertical direction may be changed on the cam mechanism 222 side (not shown). For example, the upper cam 225 of the cam mechanism 222 may be provided with a movable part that changes the height of the upper surface so that the vertical distance from the lower surface of the cam driver 223 can be changed.

  In the above-described embodiment, the case where the lower cam 224 is fixed to the plate 208 and the upper cam 225 is slid to move the prehem blade 221 to the workpiece side is shown, but the present invention is not limited to this. For example, although not shown, the inclined surfaces 224a and 225b of the lower cam 224 and the upper cam 225 are inclined surfaces that are inclined in the opposite direction to the above embodiment (that is, inclined surfaces that are raised toward the workpiece side). The lower cam 224 may be slid toward the workpiece by lowering the upper cam 225 vertically downward, and the prehem blade 221 may be pushed into the workpiece with the lower cam 224 (not shown).

DESCRIPTION OF SYMBOLS 1 Inner panel 2 Outer panel 200 Hemming processing apparatus 200a Lower mold 200b Upper mold 201 Base 202 Ram 203 Work receiving part 204 This hem blade 205 First drive means 206 Second drive means 207 Guide member 208b Movable base 210 Guide pin 220 Prehem mechanism 221 Pre-hem blade 222 Cam mechanism 223 Cam driver 224 Lower cam 225 Upper cam 230 Lock mechanism

Claims (3)

Provided in the upper die, a lower die, an upper die that can be raised and lowered relative to the lower die, a prehem blade that is slidable in a direction approaching and moving away from the side with respect to a workpiece set in the lower die. A hemming processing apparatus comprising a cam driver and a cam mechanism that slides a pre-hem blade toward a workpiece by being pressed downward by the cam driver,
A hemming apparatus in which a horizontal flat surface is provided on the lower surface of the cam driver and the upper surface of the cam mechanism which are in contact with each other.   The hemming processing apparatus according to claim 1, wherein a vertical distance between a lower surface of the cam driver and an upper surface of the cam mechanism facing each other in the vertical direction can be changed in a state where the upper mold is stopped. A lower die, an upper die that can be raised and lowered with respect to the lower die, a prehem blade that is provided in the lower die and is slidable in a direction approaching and separating from a side with respect to a workpiece set in the lower die; Hemming provided with a cam driver provided on the upper die and a cam mechanism for sliding a pre-hem blade toward the workpiece, and a flat surface in the horizontal direction provided on the lower surface of the cam driver and the upper surface of the cam mechanism that contact each other A hemming method performed using a processing apparatus,
The upper die is lowered and the cam mechanism is pressed downward by the cam driver to slide the prehem blade to prehem the workpiece, and the upper die is raised to move the prehem blade to the workpiece. Separating the upper mold, increasing the vertical distance between the lower surface of the cam driver and the upper surface of the cam mechanism facing each other in the vertical direction with the upper mold stopped, and the pre-hem processing of the upper mold The hemming processing method which goes through the step which descends below from the position which gave.

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