AU748239B2 - Pressing apparatus - Google Patents

Description

1- P/00/0 1 1 Regulation 3.2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Invention Title: PRESSING APPARATUS The following statement is a full description of this invention, including the best method of performing it known to us: GH REF: P25138-B:MHK:RK

SPECIFICATION

Title of the Invention PRESSING APPARATUS Detailed Description of the Invention Field of the Invention The present invention relates to a pressing apparatus for shaping a metal sheet.

Background of the Invention For shaping a metal sheet, a material to be worked, into a recessed form stepping into a lower die from a 15 downward path of an upper die, a slide cam is commonly used.

In general, when a metal sheet, a material to be worked, is shaped into such a recessed form, the material S-to be worked is put on the lower' die and then the upper die is lowered vertically to drive a passive cam of the lower die via a driving cam of the upper die, so as to work the material to be worked from a lateral side. After completion of the working of the material, the upper die is raised up and then the passive cam is moved back by a spring. In this S 25 general type pressing apparatus, a shaping portion of the passive cam, which is slid from a lateral side of the material to be worked at the outside thereof to shape the material, is formed in one piece to have the same shape as a shaping portion of the material, but a shaping portion of the lower die on which the material to be worked is put must be taken Out from the lower die after completion of the working of the material. Due to this, it is necessary for the removal of the worked material after completion of the working of the material that a recessed portion of the lower die is divided and then backed, or that a rear part of the recessed portion is eliminated and the worked material is moved forward. In a case where the magnitude of I S:25138B 1 recession is slight, little problem arises. However, in a case where the magnitude of recession is big or in a case where the worked material is an elongate frame-like part having a groove-like shape in cross section, such as a front pillar outer of an automobile made of a metal sheet, since the grooved.part of the worked material is narrow in width, the division or elimination of the recessed portion of the lower die arises not only a problem that the material is not shaped clearly by the shaping portion of the passive cam but also a problem that strength of the lower die is lacked so that the shaping of the recessed portion cannot be achieved. In addition with the structure in which the passive cam must be slid linearly over a S: rather long distance to shape the material into a recessed 15 form by use of the slide cam, it is not necessarily easy S.that the passive cam is slid repeatedly between specified positions with accuracy, and thus it is difficult to *manufacture products with stable levels of quality.

Further, there are some occasions when twist or distortion occurring in the products must be corrected, but, since components of an automobile, outside plate portions, such as a side panel, a front fender, a roof, a bon-net, a trunk lid, a door panel and a front pillar outer, have :three-dimensional curved surfaces and lines, it is substantially impossible to correct such products. When the metal sheets of an automobile are assembled, the twist or distortion in the products makes it difficult to combine with other parts. As a result of this, an automobile metal sheet structure of high level of quality cannot be furnished and the required accuracy of the shaped metal sheet is not able to be maintained. Also, the use of this slide cam requires that a large passive cam and a heal are provided at a side of the lower die on which the material to be worked is put and increases an area of the lower die, with the result that the pressing apparatus increases in weight and costs to that extent.

S:518In view of the above said problems, the applicant 1iL-I/ S:25138B 2 developed a pressing apparatus capable of converting a vertical linear motion of a press into a rotary motion.

Summary of the Invention In accordance with one aspect of the present invention, there is provided a pressing apparatus comprising a lower die having a supporting portion on which a material to be worked of a metal sheet is put; an upper die movable downward linearly with respect to said lower die to abut on the material to be worked; a cylindrical member rotatably disposed in said lower die, said cylindrical member having a groove opening to an outer surface and engraved along its axial direction and a recess shaping portion formed at an 1 edge portion of said groove near to said supporting portion 15 and stepped inside from a path of said upper die; a slide cam i: having a recess shaping portion and slidably arranged on said upper die confronting said cylindrical member; and an e• Sautomatic return element, provided in said lower die, for rotationally backing said cylindrical member to a position at 20 which said material after shaped can be taken out from said :lower die, whereby the material to be worked put on said supporting portion of said lower die is shaped by said recess shaping portion of said cylindrical member being rotated and :said recess shaping portion of said slide cam being slid, and 25 after completion of the shaping of the material, said cylindrical member is rotationally backed by said automatic return element so that the worked material can be taken out from said lower die, wherein a recess shaping portion of the material to be worked having a curved form when said lower die is viewed from said upper die is divided into a plurality of shaping portions to provide a substantially straight line form which can be worked by said cylindrical member, and also said cylindrical member and said automatic return element are arranged specifically for each of the divided portions of the material to be worked.

Preferably, rotation timing of the divided cylindrical members is staggered to prevent intervention when rotated 3 at junctions of adjoining cams, and after rotation of the cylindrical members, the material-to-be-worked supporting portions and recess shaping portions of the cylindrical members are connected with each other smoothly so as to provide a thorough product form, whereby the curved material to be worked is enabled to be shaped into a recessed form by a- plurality of cylindrical members. It should be noted that the rotation axes of the cylindrical members cross each other at the junctions of the cylindrical members and the material-to-be-worked supporting portions and the recess shaping portions must be shaped into a product form without deforming the material, so that the junctions must be shaped in such a form as to prevent intervention. However, the end portions of the 15 cylindrical members are not allowed to be shaped into cone for avoidance of the intervention, because the cone shaped go o ends create gaps between both cylindrical members to cause deformation in the material to be worked, when the material S"is shaped into a recessed form.

Brief Description of the Drawings Preferred embodiments of the present invention will now S. be described by way of example only, with reference to the eeo: accompanying drawings, in which: 25 Fig. 1 is a plan view of an example of the preferred embodiment of a pressing apparatus of the invention; Fig. 2 shows two sectional views of a part of a material to be worked taken along the line V -V in Fig. 1 before shaped into a recessed form and after shaped into the recessed form; Fig. 3 is a longitudinal sectional view taken along the line III-III in Fig. 1; Fig. 4 is a longitudinal sectional view taken along the line IV-IV in Fig 1; Fig. 5 is a longitudinal sectional view taken along the line V-V in Fig. 1; Fig. 6 shows sectional views of a front pillar outer of S:25138B 4 an automobile of a metal sheet before worked and after worked; Fig. 7 is a longitudinal sectional view of an upper die of the pressing apparatus, positioned at a top dead center, for shaping the front pillar outer of Fig. 6 into a recessed form; Fig. 8 is a longitudinal sectional view of the upper die of the pressing apparatus of Fig. 7 lowered and contacting with the lower die; Fig. 9 is a longitudinal sectional view of the upper die of the pressing apparatus of Fig. 7 positioned at a bottom dead center; and Fig. 10 is a longitudinal sectional view of the upper of the pressing apparatus of Fig. 7, raised up and 15 positioned at the top dead center after shaping the front o pillar outer in the recessed form.

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Embodiment S"Referring now to the accompanying drawing figures 1 through 5, an example of another preferred embodiment of a pressing apparatus of the invention is described below.

As shown in Fig. 1, it is an front door outer of an automobile that is shaped by the pressing apparatus of the :invention. Specifically, as shown in Fig. 2, a circular 25 arc curved portion of the front door outer at the top is shaped into a recessed form so that it can be changed from the upper sectional view into the lower sectional view. A downward edge 176 and an outward flange 177 continuously extending from the downward edge 176 at a bottom right in the figure are formed into an inward slanted edge 178 facing inward in a downward slanting direction. While the circular arc curved part of the front door outer at the top curves considerably, a cylindrical member is rotated on its rotation axis. Due to this, one cylindrical member cannot hold a recess shaping portion of the front door outer therein, so that it is impossible to work the front door outer with one cylindrical member. Accordingly, the 5 circular arc curved part isdivided into three parts to provide a generally straight line form which can be worked by one cylindrical member. Specifically, the circular arc curved portion is divided into a center part of a small radius of curvature at the center and two associated parts at the both sides of the center part. The circular arc curved portions of the door outer can be shaped into a recessed form, with the cylindrical member divided into three parts.

Fig. 1 is a plan view of the pressing apparatus of the invention, in which the material 100 to be worked of the front door outer of automobile is put in flat on supporting members 103, 153, 163 and the cylindrical member is divided into three parts. A cam B is arranged at 15 a part of the circular arc curved portion having a small radius of curvature, and a cam A and a cam C are arranged at parts having a large radius of curvature. In this embodiment, the cam A and the cam C are identical in structure.

The cam A is shown in Figs. 1, 3 and 4. In the cam A, a lower die 101 includes the supporting member 103 for 9 oe putting the material 100 to be worked thereon and .osupporting blocks 104 for supporting the cylindrical members 106, 156. The cylindrical member 106 is rotatably 25 supported between the supporting blocks 104 and the Ssupporting member 103.

The cylindrical member 106 having a cylindrical shape is formed around the rotation axis CA and is provided with an axially extending groove 107 whose outer surface opens for receiving a slide cam 126 described later therein.

Cylindrical member supporting portions of the supporting blocks 104 at the top and a cylindrical member supporting portion of the supporting member 103 at the side are formed in circular arc so as to fittingly support the cylindrical member 106. A top portion of the supporting member 103 is formed as a material-to-be-worked mounting portion 108 having the same shape as a related part of the S:25138B 6 material to be worked 100 so as to fittingly support the material 100. A portion of the cylindrical member 106 to extend continuously from the material-to-be-worked mounting portion 108 of the supporting member 103 is formed as a material-to-be-worked supporting portion 109 having the same shape as a related part of the material to be worked 100. The material-to-be-worked mounting portion 108 and the material-to-be-worked supporting portion 109 are formed to be identical in shape with the product so that the material can be prevented from being deformed when shaped into a recessed form. One side surface of the groove 107 of the cylindrical.member 106 near to the material-to-be-worked supporting portion 109 is formed as .a recess shaping portion 110. The other side surface of 15 the groove 107 is provided with a rotary plate 111 fixed

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thereto with bolts 112. Further, a wear plate 113 is fixed

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on a top surface of the supporting block 104 at the o..

outside of the rotary plate 111 with bolts 114, so as to guide a slide cam described later.

In the cam A, the cylindrical member 106 is supported at the both ends by the supporting blocks 104, as shown in Fig. 1, and a timing plate 115 for controlling rotation timing of the cam .A to the cam B or the cam C is provided between the supporting blocks 104, as shown in Fig. 4.

25 On the other hand, an upper die 121 is provided with a slant guide 123, on the bottom surface of which a slide cam 126 biased toward the outside of the pressing apparatus by a coiled spring 125 is arranged to be slidable with guided (not shown). The slide cam 126 is stopped in place by a stop plate 128 projecting from the slant guide 123 at the bottom end.

On the slide cam 126 at a bottom portion thereof facing the groove 107 of the cylindrical member 106, a recess shaping member 129 is fixed with bolts 130, and a recess shaping portion 131 is formed on a top surface of the recess shaping member 129.

As shown in Fig. 4, a base end portion of the timing S:25138B 7 plate 115 is fixed on a lower side surface of the groove 107 of the cylindrical member 106 with bolts 141, and a pressing spring 145 is provided between a front end portion of the timing plate 115 and a bracket 144 fixed to the lower die 100 with bolts 143. The timing plate 115 is rotated together with the cylindrical member 106 to be brought into a state indicated by a two-dot chain line when it is not pressed by the slide cam 126. Thus, the cylindrical member 106 is rotationally backed so that the material 100 shaped into a recessed form can be taken out from the supporting member 103.

When a bottom surface of the slide cam 126 is brought into contact with a front end portion 146 of the timing plate 115, the cylindrical member 106 starts to rotate.

15 Thus, the rotation timing of the cylindrical member 106 can be determined by the distance from the rotation axis CA of the cylindrical member 106 to the front end portion 146 of the timing plate 115. The longer the distance S"between the rotation axis CA of the cylindrical member 106 and the front end portion 146 of the timing plate 115 becomes, the faster the cylindrical member rotates, and the shorter the distance becomes, the slower the cylindrical member rotates.

The cam C is identical in structure with the cam A, 25 though its sectional view is not shown. In the cam C, the cylindrical member 156 having its rotation axis Cc is arranged in a rotatable manner between the supporting blocks 104 and the supporting member 153. The cylindrical member 156 is rotatably installed between the two supporting blocks 104, and the timing plate 115 identical with that in the cam A is arranged between the supporting blocks 104 so that the cylindrical member 156 can be rotated with the same rotation timing Also, just as in the case with the above-mentioned general type pressing apparatus, this pressing apparatus also includes a pad 171 serving to press the material 100 against the supporting S:25138B -8 members 103, 153, 163 strongly, before the material 100 is shaped into a recessed form. The pad 171 is biased downwards by a coiled spring 172 and is hung from the upper die 121 via a hanging bolt 173.

Shown in Fig. 5 is the cam B, in which the supporting member 163 is projected from the lower die 101, and the cylindrical member 166 having its rotation axis CB is rotatably placed in a center portion of the supporting member 163 at the top. A timing plate 168 is fixed on a lower side surface of the groove 167 of the cylindrical member 166 with bolts 169. The timing plate 168 is rotated by a push pin 181 placed in the lower die 163 and biased by a coiled spring 170 and thus the cylindrical member 166 e g..is rotated, so that the material 100 shaped into a 15 recessed form can be taken out from the supporting member CoS 163.

As mentioned above, an automatic return element for ooo the cylindrical member 166 in the cam B is different in type from those in the cams A and C. In this embodiment, the cam B is so set as be behind the cams A and C in its rotation. Accordingly, when the upper die 121 is moved ooe• down, with the front door outer of automobile of the material 100 put on the supporting members 103, 153, 163, ooe.

so as to bring the slide cam 126 into contact with the 25 timing plate 115, the cylindrical members 106, 156 in the cams A and C are rotated first to be brought into a standby mode and thereafter the cylindrical member 166 in the cam B is rotated to be brought into a standby mode.

In the standby mode, the material-to-be-worked supporting portions 109 and recess shaping portions 110 in the cams A, C and B are so set that they can be connected with adjoining cams so smoothly as to provide a thorough product form Otherwise, deformation will occur when the material 100 is shaped into a recessed form. Also, the material-to-be-worked mounting portions 108 of the supporting member 103, the material-to-be-worked supporting portions 109 and recess shaping portions 110 of S:25138B 9 the cylindrical members 106, 156, 166 are so set that they can be connected with each other so smoothly as to provide a product form, in order to prevent the material 100 from being deformed. In addition to this, thejunctions between the ends of the cylindrical members 106, 156, 166 are formed into suitable shapes and are so set as to prevent the cylindrical members from intervening in each other when rotated.

With strongly pressed with the pad 171 on the supporting members 103, 153, 163 and the material-to-beworked supporting portions 109 of the cylindrical members 106, 156, 166, the material 100 to be worked is shaped into a recessed form by the recess shaping portions 110 of the cylindrical members 106, 156, 166 and the recess shaping portions 131 of the slide cams 126. After completion of i: the shaping of the material 100, the upper die 121 is moved go up and the slide cams 126 biased by the coiled spring 125 are moved toward the outside of the pressing apparatus, so that intervention between the recess shaping portions 110 of the cylindrical members 106, 156, 166 and the recess shaping portions 131 of the slide cams 126 are prevented.

With the upward movement of the upper die 121, the timing plates 115 and push pin 181 are raised up by the pressing springs 145 and the coiled spring 170 to rotationally back S. 25 the cylindrical members 106, 156, 166, so as to allow the worked material 100 to be taken out from the supporting members 103, 153, 163.

In the embodiment described above, the cam A and the cam C are so set as to be rotated with the same timing and only the cam B is so set as to be behind the cams A and C in its rotation. The rotation timing of the cams may be properly regulated according to the material to be worked.

In addition, other suitable mechanisms than the means described in the above-described embodiment may be used to provide the rotation timing.

One embodiment of the pressing apparatus is described below by way of example only, with reference to the S:25138B 10 accompanying drawing figures 6 through Fig. 6 shows sectional views of a front pillar outer 6 of a metal [sheet of an automobile before worked and after worked with the pressing apparatus. The front pillar outer, which forms a part of a front door frame and a part of a windshield frame and also serves as a part of a frame supporting a roof panel, has a lot of joints to other parts and its product accuracy is strictly required. If the product does not meet the requirements of product accuracy, a car body made of metal sheets of high quality will be unable to be furnished.

Also, the front pillar outer forming an outer plate portion of an automobile has three-dimensional curved surfaces and lines.

15 The front pillar outer is shaped into a recessed form as illustrated by the pressing apparatus of the invention.

In the press working, the front pillar outer is first subjected to drawing and then trimming at its outer region e into a state shown in Fig. 7. At the next third step the shaping is done.

The lower die 1 is provided at a top portion thereof with a supporting portion 12 for the material 6 to be worked. In the lower die 1, a cylindrical member 5 is rotatably arranged which has a groove 2 opening to an S 25 outer surface and engraved along its axial direction and a recess forming portion 4 formed at an edge portion of the groove 2 on the supporting portion 12 side and stepped inside from a path of an upper die 3. A top surface of the lower die 1 is formed as the supporting portion 12 to put the material 6 to be worked thereon. A recess forming portion 4 is formed at an edge portion of the groove 2 of the cylindrical member 5 near to the supporting portion 12 of the lower die 1. An automatic return element 7 for rotationally backing the cylindrical member 5 is placed in the lower die 1 so that the material 6 to be worked can be taken out from the lower die i, after shaped. In this embodiment, the automatic return element 7 includes a J S:25138B 11 coiled spring 8 placed in the lower die i. The automatic return element 7 allows a push pin 9 biased by the coiled spring 8 to contact with a bottom surface of a rotary plate 11 at the tip thereof fixedly mounted on a surface of the cylindrical member 5 confronting the recess forming portion 4 of the groove 2 with bolts Alternatively, the automatic return element may be composed of another suitable element, such as a pneumatic power unit, a hydraulic power unit, a linkage, a cam, or the like.

The upper die 3 is provided with a slide cam 13 slidable to a position opposite to the cylindrical member.

The slide cam 13 is provided at a lower end thereof with a recess forming portion 14 and is guided by -a guide (not 15 shown). The slide cam 13 is biased toward the outside of the die by a coiled spring 15 compressed and interposed :00 between an upper surface of the slide cam 13 and a slanted guide portion 19 and is stopped in place by a stop projecting from the slanted guide portion 19.

A pad 16 is biased downwards by a coiled spring 17 and is hung from the upper die 3 via a hanging bolt 18. The pad 16 serves to press the material 6 to be worked against the lower die 1 so strongly that the material 6 can be oo.. prevented from being out of position before shaped into a 25 recessed form.

The operations of one embodiment are described below.

First, as shown in Fig. 7, the upper die 3 is in the upper dead center, when the material 6 to be worked is put on the supporting portion 12 of the lower die 1. At that time, the cylindrical member 5 is rotationally backed by the automatic returning element 7.

Then, the upper die 3 begins to move down, and, as shown in Fig. 3, the pad 16 presses the material 6 against the supporting portion 12 first and then the bottom surface of the slide cam 13 comes to contact with the rotary plate 11 without intervention in the recess forming portion 4 of the cylindrical member 5, to turn the cylindrical member L S:25138B 12 clockwise as viewed in Fig. 8.

When the upper die 3 continues to move down, the slide cam 13 biased toward the outside of the pressing apparatus is moved transversely to the left side against a biasing force of the coiled spring 15 by the action of cam and comes into a state as shown in Fig. 9 in which the material 6 to be worked is shaped into a recessed form by the recess forming portion 4 of the as-turned cylindrical member 5 and the recess forming portion 14 of the slide cam 13.

After completion of the shaping of the recess, the upper die 3 begins to move up. The slide cam 13 biased toward the outside of the pressing apparatus by the coiled spring 15 is moved to the right side as viewed in Fig. so that the slide cam is raised up without intervention with the worked material 6 shaped into the recessed form.

On the-other hand, the cylindrical member 5 is rotated counterclockwise as viewed in Fig. 10 by the automatic return element 7, as the slide cam 13 restraining movement of the cylindrical member 5 is moved up. As a result, when the worked material 6 shaped into the recessed form is taken out from the lower die 1, the worked member 6 does not intervene with the recess forming portion 4 of the cylindrical member 000* o*oo This shaping of a metal sheet into a recessed form S 25 using the cylindrical member which is rotated on its rotation axis for shaping the material is suitable for a material to be worked having such a substantially straight line form when viewed from the working direction that a recess shaping portion of the material can be held in one cylindrical member, but is not applicable to a material to be worked having such a curved form that the recess shaping portion cannot be held in one cylindrical member.

Among others, automobile parts of metal sheets, from a door panel down, have a lot of curved portions and yet have been required in recent years to have recess shaping portions as well as curved portions, because of car design, so that it is desired that the recess shaping portions of 13 the material be shaped in one step without subjected to lots of steps, to provide improved productivity.

It is preferably an advantage of the present invention that a recess shaping portion of a curved material to be worked is shaped, the.recess shaping portion divided into a plurality of recess shaping portions to provide a substantially straight line form which can be worked by one cylindrical member, to enable even the curved material to be shaped into a recessed form. The length with which a recess shaping portion of the curved material is to be divided is determined by the extent to which one cylindrical member can occupy the recess shaping portion of the material. If the width of the cylindrical member is fixed, the length of the cylindrical member is naturally 15 determined by the curvature of the recess of the material.

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ft C C Co .c S:25138B 14

Claims (3)

1. A pressing apparatus comprising: a lower die having a supporting portion on which a material to be worked of a metal sheet is put; an upper die movable downward linearly with respect to said lower die to abut on the material to be worked; a cylindrical member rotatably disposed in said lower die, said cylindrical member having a groove opening to an outer surface and engraved along its axial direction and a recess shaping portion formed at an edge portion of said groove near to said supporting portion and stepped inside from a path of said upper die; a slide cam having a recess shaping portion and 15 slidably arranged on said upper die confronting said S"cylindrical member; and an automatic return element, provided in said lower .o9 die, for rotationally backing said cylindrical member to a position at which said material after shaped can be taken out from said lower die, SIP* whereby the material to be worked put on said supporting portion of said lower die is shaped by said recess shaping portion of said cylindrical member being o*o rotated and said recess shaping portion of said slide cam being slid, and after completion of the shaping of the material, said cylindrical member is rotationally backed by said automatic return element so that the worked material can be taken out from said lower die, wherein a recess shaping portion of the material to be worked having a curved form when said lower die is viewed from said upper die is divided into a plurality of shaping portions to provide a substantially straight line form which can be worked by one cylindrical member, and also one cylindrical member and said automatic return element are arranged specifically for each of the divided portions of the material to be worked. Lu S:25138B 15

2. A pressing apparatus according to Claim 1, wherein rotation timing of the divided cylindrical members is staggered to prevent intervention when rotated at junctions of adjoining cams, and after rotation of said cylindrical members, said material-to-be-worked supporting portions and recess shaping portions of said cylindrical members are connected with each other smoothly so as to provide a thorough product form.

3. A pressing apparatus as substantially described herein with reference to the accompanying drawings. Dated this 8th day of September 1997 e UMIX CO., LTD. By their Patent Attorney GRIFFITH HACK oo *0 .o 0 16