Die assembly for plural kinds of works

Abstract: A die assembly (50) for processing a plurality of different kinds of works each having a peculiar shape portion providing a peculiar shape and a common shape portion. A multiple face die (26) which has a plurality of processing faces having different shapes each corresponding to the peculiar shape portion of each kind of work, is provided on a base (14) relative to which each work can be positioned by utilizing the common shape portion (44) thereof, such that it is operable to select one of the processing faces (30,31).

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a die assembly used for performing press operation on automotive door inner panels or like works. The workpieces to be processed by the die assembly are classified into a plurality of different groups or kinds, while they each have a portion having a shape common to all kinds and a portion having a shape particular to each kind. For example, automotive door inner panels are classified into different kinds corresponding to respective different models, while they each have a common shape portion such as an inner trim mounting portion common to all kinds and a particular shape portion such as an edge hemming face particular to each kind. The present invention concerns a die assembly for carrying out a press operation so as to form a selected kind of workpiece. 2. Description of the Prior Art Heretofore, a plurality of die assemblies for the above press operation have been prepared each particular to the kinds of workpiece. These die assemblies each have a press operation shape particular to each kind of workpiece, and they are used selectively in conformity to the kind of workpiece. This means that it is necessary to prepare die assemblies corresponding in number to the number of different kinds of workpieces, thus increasing equipment cost. In addition, the die assembly replacement requires considerable time, that is, a considerably long time is needed for preparations before the press operation. From DE-A-1452821 a die assembly is known that is capable of being used in association with another die assembly for forming a plurality of different kinds of workpieces, the die assembly comprising a multiple face die capable of being moved and having different processing faces corresponding in number to the number of the different kinds of workpieces, each processing face having a press operation shape particular to the selected kind of workpiece to be formed, the different processing faces being capable of selectively being set in an operating position in conformity with the selected kind of workpiece and being shaped so as to be capable of forming a position of the workpiece particular to the selected kind of workpiece. SUMMARY OF THE INVENTION An object of the invention is to reduce equipment cost by permitting press forming of a selected one of a plurality of different kinds of workpieces to be done with a single die assembly. Another object of the invention is to reduce time necessary for preparations prior to the press operation. According to the invention, the above objects are attained by a die assembly as defined in claim 1. With this die assembly, the workpieces can each be positioned with respect to the die assembly by utilizing their common shape portion. The plurality of processing faces of the multiple face die are used selectively. For example, a processing face for kind A is used for kind A of work, and a processing face for kind B is used for kind B of work. Each processing face has a press operation shape peculiar to each kind of workpiece. Thus, every kind of workpiece can be processed by merely selecting the corresponding processing face by moving the multiple face die. In some cases, a common member is to be mounted on each of the works. Thus, each work may have a common shape in its common member mounting portion. In this case, it is suitable to have the common member (or a member having the same shape) secured to the base. With this arrangement, each work can be positioned by positioning its common member mounting portion with respect to the common member. When the multiple face die is cylindrical in form, it is suitable to provide its outer periphery with a plurality of processing faces such that a selected one of the processing faces can be set in an operating position by rotating the cylindrical multiple face die. This arrangement permits reduction of the size of the die assembly as a whole. The present invention will be more fully understood from the following detailed description and appended claims when taken with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a die assembly according to a preferred embodiment of the invention, showing the same in use; FIG. 2 is a right side view thereof; FIG. 3 is a perspective view of a work; FIG. 4 is a sectional view taken along line A-A in FIG. 3; FIG. 5 is a plan view, to an enlarged scale, of the essential part of the die assembly shown in FIG. 1; FIG. 6 is a side view of the part shown in FIG. 5; and FIG. 7 is a perspective view of the part shown in FIGS. 5 and 6. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the invention will now be described with reference to the drawings. FIG. 1 is a plan view of a die assembly 50 in use. FIG. 2 is a right side view of FIG. 1, in which the die assembly 50 is disposed between an upper die 10 and a lower die support 12. The die assembly 50 is secured to the lower die support 12. A workpiece 40 is positioned on the die assembly 50. Then, the upper die 10 is lowered, so that pierce holes are press formed in a predetermined portion of the workpiece 40 by piercing punches (not shown) of the upper die 10. FIG. 3 shows the outer shape of one kind of workpiece 40, in perspective view, and FIG. 4 is a schematic sectional view taken along line A-A in FIG. 3. The workpiece 40 shown in FIGS. 3 and 4 is an automotive door inner panel which is to be bonded to an outer panel 41. An inner trim mounting member 44 is bonded later to the inner panel 40 at a mounting portion 40A. Near the mounting portion 40A, the workpiece 40 has a portion 42 in which the pierce holes are formed by the upper die 10 and the die assembly 50. The portion 42 of the work 40 piece has a shape corresponding to the particular kind of workpiece 40, i.e., to each of door inner panels of different models of vehicles. The inner trim mounting member 44, on the other hand, is common to all kinds of workpieces 40. This common member 44 is mounted on the mounting portion 40A of the workpiece 40. The mounting portion 40A has a common shape to all kinds of workpieces. In FIG. 3, shown by a phantom line 42a in the portion 42 is the locality of press formation of the pierce hole. FIG. 5 is a plan view, to an enlarged scale, of the essential part of the die assembly 50 shown in FIG. 1. FIG. 6 is a side view of the part shown in FIG. 5. FIG. 7 is a perspective view of the part of the die assembly 50 shown in FIGS. 5 and 6. As shown in these drawings, a base 14 is secured to the lower die support 12. The base 14 has four vertical through holes 16, and its bottom is formed with a positioning groove cross 17. The lower die support 12 has its top formed with a positioning ridge cross (not shown). The base 14 is secured to the lower die support 12 in a set position by engaging the positioning groove cross 17 and the positioning ridge cross, then inserting bolts (not shown) through the through holes 16 and tightening these bolts. The base 14 has an arcuate sectional profile support recess 18 open to the top. A multiple face die 26 having a cylindrical shape is set such that its outer periphery is supported in the support recess 18 for rotation about its axis. A retainer 20 is bolted to each end face of the base 14 to prevent axial movement of the multiple face die 26. The common part 44 which is to be mounted later on the workpiece 40, is mounted on top of the base 14 by tightening pins 46 inserted through its holes (i.e., holes of the eventual product). The common member 44 has two functions, i.e., a function of positioning and setting the workpiece 40 relative to the base 14 and a function of pushing and holding in position the outer periphery of the multiple face die 26 as is seen from FIGS. 6 and 7. It is possible to use a block exclusively for the function of pushing the multiple face die 26. In this case, the common member 44 is utilized for the sole purpose of positioning the workpiece 40. A spacer 48 may, if necessary, be used to position the common member 44 with respect to the base 14. Since the common member 44 is secured to the base 14, any kind of work can be positioned and set with respect to the base 14. As shown in FIGS. 6 and 7, the outer periphery of the multiple face die 26 has a plurality of different processing faces 30 and 31 which are spaced apart at a predetermined angular interval (i.e., substantially 90x in this embodiment) in the direction of rotation. The processing faces 30 and 31 each have a particular shape in correspondence to the workpiece portion 42 which is different for each kind of workpiece 40. The processing faces 30 and 31 each have piercing holes 32 each provided near each end thereof to receive piercing punches (not shown) of the upper die 10 during piercing process. The piercing holes 32 of the processing face 31 are not shown. The processing faces 30 and 31 need be provided only in the neighborhood of the piercing holes 32. Thus, the other portion of the multiple face die 26 (i.e., the intermediate portion thereof) may be of a circular profile of a reduced diameter so that it is free from interference with the workpiece 40. This construction permits increase of the contact surface of the multiple face die 26 with the common member 44 that is mounted on the base 14 and the workpiece 40. A handle 28 is provided on the multiple face die 26 at an end thereof, and is operable to rotate the multiple face die 26. The multiple face die 26 has radial through positioning holes 36 and 37 in correspondence to the respective processing faces 30 and 31. These positioning holes 36 and 37 can be selectively aligned to lock pin insertion holes 24 which are formed in the base 14 such as to extend from the front surface of the base 14 toward the support recess 18. When the processing face 30, for instance, is selected and positioned to be at the top as shown, the positioning holes 36 corresponding to the processing face 30 is aligned to the lock pin insertion holes 24 in the base 14. In this state, the multiple face die 26 can be locked against rotation relative to the base 14 by inserting lock pins 38 as shown in FIGS. 5 and 6. The pierce hole formation with the die assembly 50 thus constructed will now be described. First, in a preparatory operation, the processing face 30 (or processing face 31) corresponding to the kind of the pertinent workpiece 40, i.e., the shape of the portion 42, is positioned to be at the top by rotating the multiple face die 26 with the handle 28 after taking out the lock pins 38. In this state, the multiple face die 26 is locked to the base 14 by inserting the lock pins 38 into the positioning holes 36 of the multiple face die 26 corresponding to the processing face 30. Then, a predetermined portion of the workpiece 40 is engaged with the common member 44 mounted on the base 14 and complementary thereto in shape, so that the workpiece 40 is positioned relative to the base 14. In this state, the portion 42 of the workpiece 40 is positioned on top of the processing face 30 of the multiple face die 26, and the pierce hole formation localities as shown by phantom line 42a in FIG. 3 are coincident with the positions of the piercing holes 32 of the multiple face die 26. Then, the upper die 10 as shown in FIG. 2 is lowered, so that the pierce holes are formed in the portion 42 by the piercing punches (not shown) of the upper die 10 as described before. Scrap produced by this processing is led through the multiple face die 26 and the base 14 to be received by the lower die 12 shown in FIGS. 1 and 2 for disposal. To change the processing face 30 over to the other processing face 31 in conformity to the selected kind of workpiece 40, the lock pins 38 are taken out, and the processing face 31 is brought to the top position by rotating the multiple face die 26. Then, in this state, the lock pins 38 are inserted again through the lock pin insertion holes 24 of the base 14 into the positioning holes 37 of the multiple face die 26 corresponding to the processing face 31. By the above simple operation, the processing faces 30 and 31 of the multiple face die 26 can be selectively used in correspondence to the kind of workpiece 40 (i.e., the shape of the portion 42 of workpiece 40). The change of the processing faces 30 and 31 can be automated by controlling the insertion and take-out of the lock pins 38 and the rotation of the multiple face die 26 by actuators, such as cylinders and motors. While, in the above embodiment, the processing faces 30 and 31 have been described in relation to the case where they correspond to two kinds of workpieces 40 different in the shape in the portion 42, respectively, they may correspond as well to two portions 42, respectively, having different shapes, of a single workpiece 40 which includes further the two common portions. It is further possible to provide three or more processing faces 30 and 31 by reducing angular intervals between the processing faces of the multiple face die 26 and with respect to the direction of rotation. The operation of the multiple face die 26 for changing the processing faces 30 and 31 may be of sliding type as well, instead of the rotating type. In this case, a desired shape may be selected for the multiple face die 26. The workpieces 40 may not only be automotive door inner panels, and also the press operation on the workpiece 40 may be a bent formation, etc., as well as the pierce formation. While a preferred embodiment of the invention respectively the use thereof has been described, it will be appreciated that the following modifications may be made: 1. The operation of the multiple face die for selecting one processing face can include an operation of locking the multiple face die relative to the base or releasing the lock of the multiple face die. 2. The multiple face die can be locked relative to the base or released from the lock by inserting or taking out lock pins into or from the base and the multiple face die. The multiple face die thus can be readily locked relative to the base or released from the lock, and also it can be held in a stable state of lock. 3. The multiple face die can be a cylindrical member rotatably supported on the base and having a plurality of processing faces having different shapes formed on its outer periphery. It is thus possible to relatively readily secure a plurality of processing faces and select the processing face in a simple operation. 4. The press operation can be performed to form a pierce hole in a workpiece. While the invention has been described with reference to the preferred embodiment thereof, it is to be understood that modifications or variations may be made without departing from the scope of the present invention which is defined by the appended claims.

Claims: A die assembly (50) capable of being used in association with another die assembly (10) for forming a plurality of different kinds of workpieces each including a portion having a shape common to all kinds of workpieces and a portion having a shape particular to each kind of workpiece, the die assembly comprising: a base (14, 44) capable of positioning each workpiece in contact with the common shape portion thereof, the base having a processing face (44) shaped so as to be capable of forming the common shape positions of the different workpieces; and a multiple face die (26) capable of being moved relatively to the base (14, 44) and having different processing faces (30, 31) corresponding in number to the number of the different kinds of workpieces, each processing face having a press operation shape particular to the selected kind of workpiece to be formed, each of the different processing faces (30, 31) being capable of selectively being set in an operating position in conformity with the selected kind of workpiece and being shaped so as to be capable of forming the position of the workpiece which is particular to the selected kind of workpiece. The die assembly according to claim 1, wherein the different kinds of workpieces each includes a common shape portion suitable for mounting a common part, and wherein the base (14, 44) is adapted to hold the common part. The die assembly according to claim 1, wherein the multiple face die (26) has a substantially cylindrical shape and is capable of being rotated relative to the base (14, 44). The die assembly according to claim 3, wherein the substantially cylindrical multiple face die (26) is locked against rotation to the base (14, 44) by a pin (38) extending therethrough in a radial direction thereof.

Inventors: MUKAI JUN, MUKAI, JUN
Applicants: TOYOTA MOTOR CO LTD, TOYOTA JIDOSHA KABUSHIKI KAISHA
Application year: 1996
Main classification: B21D5
IPC codes: B30B15, B21D28, B21D19, B21D43, B21D22