GB2053056A - Method and apparatus for pressing metal containers - Google Patents

Abstract

Containers have their bodies produced from metal strip by a multiple drawing operation performed in an inverted press having several forming stations (108, 112, 116, 121) each provided with a punch (111, 114, 119, 123) and a die (109, 113, 117, 122). The punches and dies are fast with a stationary crown bolster (104) and a vertically-movable press slide (15) respectively, and the dies surround stationary support pedestals (105). When a metal strip is acted upon by punch (111) and die (109) at a first forming station, a workpiece blank is stamped therefrom and shaped into a flanged, cupped workpiece which is then deposited on the pedestal (105) with the flange in a predetermined plane. Transfer means (133, 150) operating in this plane then carries the workpiece to a neighbouring drawing station (112) and after drawing therein the now elongated workpiece is placed on an associated pedestal (105) where it awaits the transfer means to carry it to the next drawing station. Pedestals (105) at the different stations are of dissimilar height adapted to the progressively increasing drawing depth, such that the flange of the workpiece is always located in the predetermined plane. <IMAGE>

Description

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SPECIFICATION

Method and apparatus for pressing metal containers

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The present invention relates to method and apparatus for pressing metal blanks into containers.

Various types of presses have previously 10 been employed to produce thin metal containers, such as those of the cylindrical drawn metal type usually having greater longitudinal dimensions than lateral dimensions. However, previous machines have tended to have cer-15 tain drawbacks: e.g., undue complexity, excessive space requirements of operation and contamination control, and excessive power consumption. Moreover past processes have required unnecessary transfer of partially 20 formed containers from one press to another during multiple drawing, thus exposing them to the possibility of damage during transfers.

Attempts have been made to improve upon the above-noted deficiencies. Improved 25 presses are described in United States Patents Nos. 3,683,665 and 4,026,226, the latter being what is known as an inverted press. It is common to feed a press with strip feedstock by angling a stack of strips so that the top 30 strip can slide from the stack into the press with the aid of gravity. It is uncommon to feed metal strips into a drawing press by lifting strips off a horizontally disposed stack and then individually feeding them. More par-35 ticularly, a conveyor and elevator system adapted to provide a continual supply of specifically positioned strips for a lifting and feeding means is unique. The invention may feature means for prelubricating the strip be-40 fore forming and in that regard the U.S.

Patent No. 2,302,856 shows a reciprocating die for pumping lubricant while U.S. Patent No. 2,107,577 shows a system for oiling near a cutting edge. None of the art includes 45 a technique which confines the lubricant to a specific predetermined area and interrupting means to prevent lubrication when there is no strip. It is common to form drawn articles progressively as they proceed along a planar 50 path through a progressive press, and a typical progressive press is disclosed in U.S.

Patent No. 1,725,330. However, so far as it is known, no presently available press affords the advantages of that of the present inven-55 tion, nor lends itself to the production of containers by the hightly accurate, facile and economic method herein set forth. In progressive presses it is common to transfer the workpiece article from station-to-station as it is 60 progressively formed. Commonly, articles are transferred by carrying them with the strip portions which ultimately are discarded as scrap. In addition, complicated and heavy transfer mechanisms have been used to trans-65 fer individual semi-finished articles as necessary, see for example U.S. Patents Nos. 3,800,583 and 3,620,382. None of the prior art, however, include a light weight, low inertia mechanism which pivots toward the con-70 tainers and thus permits high-speed handling. Rarely do such presses include a system for handling semi-finished articles which are so different in shape as to require additional means to maintian a portion of each within a 75 common plane thereby facilitating handling. However, so as far as it is known, no presently available press affords the advantages of the present invention, nor lends itself to the production of containers by the highly accu-80 rate, facile and economic method set forth herein.

The press described hereinafter with reference to the drawings is compact, and of relatively simple design, and is economical, 85 durable and convenient to use. The press owes much to the minimised handling of the workpiece necessary during foming into a container for its efficiency and smooth, highspeed operation, and contamination of con-90 tainers produced on the press is minimised. The press is especially adapted for the production of drawn thin metal containers such as multiple drawn containers having a greater depth than diameter. The operations of cupp-95 ing, drawing, redrawing and trimming are accomplished with each stroke of the press with constant control over the position and location of the workpiece during forming.

According to the present invention, there is 100 provided a mechanism for distributing work-pieces through a forming machine wherein the workpieces are progressively shaped into articles of desired shapes in a plurality of forming stations, the mechanism continuously 105 maintaining a portion of each workpiece in a common plane and including a supply means for presenting individual sheets of thin work-piece stock for blanking in a first of the forming stations which have central axes 110 about which workpieces are blanked and formed during operation of the machine, a first support means axially aligned with the first station and spaced from the common plane by the depth to which the article is 115 formed to maintain a portion of the semifinished article in the said common plane, an advance mechanism operative in a plane parallel to and adjacent the said common plane for displacing the semi-finished article from 120 the first station to another forming station while maintaining a portion of the article in the common plane, another support means opposite the latter forming station and spaced apart from the common plane by the depth to 125 which the article is formed therein to maintain a portion of said article in said common plane, and further support means similarly associated with respective further forming stations to which the advance mechanism progressively 130 transfers semi-finished articles, each said fur

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ther support means being arranged to maintain a portion of the formed article in the common plane.

The invention also provides a method of 5 transferring workpieces in a cyclically-operable press for progressively forming therefrom articles receiving some elongation during forming, the method including the steps of: (a) feeding workpiece material to be formed into 10 the press in a given plane; (b) pressing a portion of the material away from the said plane and toward a fixed support until contact occurs therewith, while at the same time retaining a portion of the material in the said 15 plane; (c) holding the formed material representing a semi-finished article against the fixed support for a specific time period related to the cycling of the press; (d) grasping the said semi-finished article about a part thereof 20 adjacent the said plane and moving the article, while keeping the said part in the said plane, a predetermined distance to another forming station; (e) re-pressing the semi-fin-ished article away from the said plane and 25 toward a second fixed support until contact therewith is made; (f) retaining the said article against the second support to maintain the said part of the article in the plane until movement thereof to further forming station; 30 and (g) progressively pressing, retaining and moving the article until the desired final form is obtained while always maintaining the said part of the progressively formed article in the said plane by means of fixedly located sup-35 ports and by controlled movement of the article.

Before describing the illustrated preferred embodiment in detail, an outline of this embodiment and its operation will be given in 40 the following description which is by way of non-limiting illustration of the invention.

The preferred embodiment is embodied in a press having a frame and a pair of vertically-spaced, interconnected platens supported on 45 the frame; one platen can move relative to the other. The platens having tooling disposed on their confronting faces providing a series of forming stations. The lower platen is mounted atop a movable slide for vertical movement, 50 enabling coaction of its associated tooling with the tooling on the upper platen. The press also has means for vertically reciprocating the slide to render the forming stations operative, and means for transferring a work-55 piece from forming station to forming station, for sequential operations to be performed on a workpiece for progressively forming it into the desired shape.

To feed the press there is a power driven 60 roller conveyor which moves pallet loads of single row slit or scroll strips in stacks into position for lifting by an elevator. The elevator provides a continuous supply to scroll strips to a strip feed mechanism. With the pallet in 65 position, an elevator unloader fork raises one stack of strips to a level for strip feed where suction cups remove strips one at a time.

When the height of the stack falls below the position of a high level sensor, feeder forks 70 extending under the stack raise it up to the height of the high level sensor, removing the load from the unloader forks and permiting them to return to their starting position. Thereupon the conveyor motor advances the 75 next pallet so that the unloader forks are under the next row of strips.

The feeder forks rise to maintain the stack of strips thereon at the strip feed level. When the feeder forks are fully raised, support of 80 remaining strips thereon is taken over by spring operated support fingers. Then the feeder forks lower and retract to their starting position, and the unloaded forks raise the next stack of strips and the cycle is repeated. 85 The raised stack of strips are held near "tin line" or at a strip feed level for four air-operated vacuum cups to lift the topmost strip until it is held by magnets positioned at the tin line. Inserters then push the strip laterally 90 into a strip feed guide through which the strip is advanced one cut edge (the diameter of a blank) and a distance for scrap allowance into a blanking and cupping station of the press. The vacuum cups lower and the next strip is 95 lifted to repeat the cycle so that a new strip is available to be inserted into the guide when the preceding strip has been advanced into or through the press.

Each strip is spot lubricated by preformed 100 pads which place a predetermined lubricant pattern on both sides of the strip for aiding drawing. The lubricating station is located between the point of strip feed and the blanking and cupping station for lubricating coated 105 or uncoated strips with a drawing compound. Each lubrication pad has absorbent material on its strip contact surface and each pad is saturated by adjustable, positive displacement spray injectors. The injectors operate only 110 when strips pass through the station where the pads intermittently contact the strip in the area within the cut edge.

The press is of an inverted type with all its moving press parts below the tin line. 115 Punches are resiliently mounted on the top platen supported by the press crown to provide a predetermined resistance to displacement. The dies are mounted below the punches on the slide and move up and down 120 during the container-forming operations. The dies also cooperate with stationary pedestals designed to maintain a formed container flange at the tin line (a common horizontal plane) within the press. The container body is 125 drawn downwardly from its flange in subsequent stations. The lower tooling is associated with fixed or stationary pedestals and acts on the upstroke of the slide by moving upward relative to the pedestals. Similarly, the tooling 130 of the upper platen acts to support portions of

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the workpieces carried in the common plane.

In the preferred embodiment, the tooling associated with each of the forming stations performs at least one forming operation of a 5 workpiece and then transfer means successively shifts the workpieces from one station to another or from one set of tools to another.

The stations are desirably positioned in linear alignment and the transfer means com-10 prises an advancing mechanism carried by the press frame for horizontal reciprocation parallel to the common plane or tin line. The advancing mechanism is operated by reciprocating means in synchronism with the down-15 ward movement of the slide. The mechanism has a plurality of cam actuated finger sets each having a pair of confronting, pivoted fingers which coact to grasp and move the workpieces from station to station. The work-20 pieces are positioned ready to be seized by the fingers on the fixed pedestals which are arranged to support a portion of each semifinished workpiece in the common plane.

In the preferred embodiment the trans-25 versely fed strip at the first station is blanked and cupped and the finger sets are pivotally mounted on a carriage of the transport mechanism for arcuate movement of their distal parts toward each other to engage the formed 30 cup therebetween thereby to shift it with the carriage to effect the transfer of the cup to the next station. Reciprocating devices shift the carriage and move the fingers in timed synchronized relation to the slide action. Desira-35 bly the mechanism should include additional sets of fingers, which further shift the work-piece (now a partially drawn container) to each subsequent station for further forming or trimming.

40 The first pair of fingers are in alignment with a pedestal in a first position before grasping and moving the container to a second position in line with the next adjacent pedestal. Each of the first and second posi-45 tions is aligned with the central axis of a pedestal which is also the axis of a forming station. The timing of the stock feeding and workpiece transfer is related to the slide movement. Means for removing scrap and 50 finished articles from the press are also provided.

In the method of operation pallets of pre-coated and re-scrolled strips of stock are automatically removed from the pallet and con-55 veyed to the first initial die inverted press. During operation the strips are transversely advanced into the first station for blanking, there the die interfaces with its blanking punch to separate a blank or disc of metal 60 from the strip, the remainder being a waste skeleton. After blanking, the operation of the cup forming is continued in the same station by a preliminary die which causes the blank to be drawn into a cup as the die mates with its 65 cupping punch. When the die thereafter descends, the cup is carried with it. The die retains control until the cup has been securely positioned on a stationary support pedestal centered along the axis of the particular die. 70 The strip scrap passes through the press with the workpiece, finally being discharged. The work progresses linearly through the press normal to the direction of the strip movement. Vacuum or electromagnets associated with 75 each stationary pedestal hold down or assist in retaining control of the workpiece cup or container until shifting is desired.

The cam actuated transfer means with individual cam controlled finger sets is caused to 80 grasp the drawn cup positively just below its flange or rim and to shift it to the next station where it is precisely aligned with the tooling for the next drawing operation. The fingers of the advancing mechanism carriage continue to 85 exert some control over the workpiece until the rising drawing die causes the cup to engage a pilot ring of the drawing punch. At this point, the fingers are cammed open as holding of the workpiece is now by the tool-90 ing. A vacuum system can be provided to hold workpieces on the pedestals at those times when they are not engaged by either the fingers or the press tooling.

After completion of the first stage of draw-95 ing, the partially drawn cup has been lengthened and reduced in diameter. Next it descends with the die to the stationary support pedestal axially centered within the drawing die. The pedestal supports the drawn cup 100 until it has been fully grasped by a finger set at which time it is released and the shifting motion of the advancing mechanism carries the cup to the next station. The cup is held by the fingers until it is again caught between 105 the next forming dies. The process is then repeated and the cup is further drawn into a longer and narrower object. As the lower die moves downward the bottom of the container is pressed against the next stationary pedestal. 110 As before the container is retained thereon until the fingers of the advancing mechanism once again grasp the container's upper side wall below the rim or flange and move it to the next forming station. Any number of sta-115 tions can be used, but, in the preferred embodiment there are four stations: the first for blanking and cupping; the second for drawing; the third for redrawing and/or bottom profiling and the fourth for trimming the 120 flange to a predetermined diameter. When the drawn container reaches the fourth station, the lower die raises up about the container until the lower surface of the flange is captured between the lower die and an upper die 125 or dies. There the dies cooperate to shear the flange to preset diameter. As the dies part a ring of flange scrap follows the lower die downwardly, and at the same time the container is lowered to the pedestal. The scrap 130 ring continues to fall with the die movement

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to a pair of horizontally cammed rails which move in and out in a plane above the top of the pedestal. The advancing mechanism then grasps the container and begins to shift it and 5 the scrap ring from the pedestal area to a point where the axis of the container is in alignment with a fifth station whereat the container is lifted to a magnetic discharge conveyor. An air jet is used to force the scrap 10 ring upwardly with the container and a further set of rails are positioned to carry the scrap ring out of the press with the magnetically conveyed container.

The invention will now be described in 15 more detail by way of example only with reference to the accompanying drawings, in which:

Figure 1 is an overall front perspective view of the preferred inverted press according to 20 the present invention;

Figure 2 is a rear perspective view of the press showing a conveyor and elevator system which feed individual workpiece strips into the press;

25 Figure 3 is a partial fragmentary elevational view looking at the side of the elevator and conveyor which supplies the strip into the press feed mechanism;

Figure 3A is a view similar to Fig. 3 show-30 ing a stack of strips lifted by an unloader fork from a pallet into position for feeding;

Figure 3B is similar to Figs. 3 and 3A, but shows the stack supported by a feeder fork with the unloader fork lowered to receive a 35 fresh stack of strips;

Figure 3C is similar to Figs. 3, 3A and 3B, and shows the remaining strips of a depleted stack thereof now supported on spring loaded fingers;

40 Figure 3D is a partial top plan view of mechanism, which extends and retracts the feeder forks, the said mechanism being shown in retracted position in Fig. 3 and in extended position in Figs. 3A or 3B;

45 Figure 4 is a partially cross-sectional view transversely of the press showing the strip feed mechanism, strip lubrication mechanism and scrap discharge in a partially cross-sec-tional side view;

50 Figure 4A is a partial, front elevational view of a portion of the lubricating system shown in Fig. 4;

Figure 5 is a longitudinal side elevational view of the press die and transfer mechanism 55 with particular emphasis on the stationary pedestals and the can conveyor;

Figure 6 is a top elevational view of the can transfer mechanism taken along line 6-6 of Fig. 5;

60 Figure 6A is a fragmentary cross-sectional view taken along line 6A-6A of Fig. 6 and showing details of the guidance system of the transfer mechanism fingers;

Figure 6B is a fragmentary cross-sectional 65 view taken along line 6B-6B in Fig. 6 of mechanism which carries the transfer mechanism and oscillates the drive for the pivoting transfer fingers;

Figure 6C is a partial side cross-sectional 70 view taken along line 6C—6C of Fig. 6 showing connections of the drive mechanism to the transfer mechanism;

Figure 7 is a longitudinal elevational view taken transversely along line 7-7 of Fig. 5 75 and showing stripping mechanism for the scrap strip, and

Figure 8 is a top plan view in cross-section along line 8-8 of Fig. 7 and showing the details of the scrap stripping mechanism. 80 Fig. 1 shows an overall front perspective view of the preferred press which is of the inverted type and is designed to perform multiple operations simultaneously to form containers in a progressive manner. More par-85 ticularly, the press has a frame generally designated 10 having a crown or top member 11 which rests horizontally across a pair of upright press walls 12 and 13. Top member 11 forms a structure adapted to carry the upper 90 portion of the tooling and upper die (not shown in Fig. 1.) The side walls 12 and 13 rest on a base 14 which is an upwardly open box-shaped hollow structure for carrying the driving mechanism of the press. A slide as-95 sembly 15 is carried for vertical reciprocating motion along and between the walls 12 and 13 and is adapted to support the lower die (not shown in Fig. 1) or tooling for the press. The press is inverted in that the slide assem-100 bly 15 is underdriven, more particularly by a crank mechanism (not shown in Fig. 1).

Fig. 2 is a perspective view of the back of the press. A drive motor 16 is positioned adjacent the base 14 and is connected by belt 105 and pulley assembly 17 to a fly wheel air clutch mechanism 18 in a manner suitable for reducing the motor speed to an appropriate speed for driving a jack or lay shaft 19 (shown in Fig. 1). The shaft 19 is horizontally 110 positioned by pillow bearings 20 on the side wall of base 14 opposite the side on which motor 16 is located and shaft 19 extends parallel to the front side of base 14. Between bearings 20 is a main drive pinion gear 21 115 meshing with and driving a larger main drive gear 22. Main drive gear 22 is a part of a press crank shaft (not shown in Figs. 1 or 2) which is drivingly connected to the slide assembly 15 for reciprocating the latter within 120 the confines generally established by side walls 12 and 13 of the press.

> Adjacent the motor 16 alongside the press base 14 (as shown in Fig. 2) is a feeder assembly 23 including a motorized roller con-125 veyor 24 which automatically presents work-piece feedstock for processing in the press. Moreover, the feed assembly 23 has an elevator mechanism 25 disposed vertically adjacent to side wall 12 and in alignment with an 130 inserter mechanism 26 carried just beneath

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top member 11 for inserting individual work-piece strips into the press in line with a first blanking and cupping station.

The conveyor 24 operates to transport pal-5 lets 27 or feed stacks into the elevator mechanism 25. More particularly, as shown in Figs. 2 and 3, a pallet 27 is moved on the motorized conveyor 24 into the elevator mechanism 25. On the pallet 27 is a feed stack 28 which 10 is typical of the material necessary for processing into drawn containers. The conveyor

24 moves the pallet 27 toward the elevator

25 whereat a set of longitudinally extending unloader forks 29 located just above the con-

15 veyor 24 extends into the pallet 27 beneath the feed stack 28 in position to lift and support the feed stack 28 independently of the pallet 27. Once captured by the unloader forks 29, the feed stack 28 is raised away 20 from the surface of the conveyor 24 and into position for feeding into the press. A pair of ball screws 31 are located at each side of unloader forks 29 and rise vertically from the conveyor bed 24a to the level of the crown 25 11. Rotation of ball screws 31 raises or lowers the unloader forks 29 in an elevator fashion. The elevator mechanism 25 is primarily located above the bed 24a of the roller conveyor 24, and the lowest position of the 30 unloader forks 29 is slightly above the top of pallet 27, such that the pallet 27 can move under the unloader fork tines 29b permitting at a later time the alignment of an additional stack 28 above the unloader forks 29. In 35 order to free the unloader forks 29 for lowering to lift further stacks of material, there is on the elevator assembly 25, an additional forked feeder assembly 30 to extend under the raised lifted stack.

40 In Fig. 3D the feeder assembly 30 is shown. It has movable tines 30a operated by a crank 30b activated by a power cylinder 30c. The main frame 30d of the assembly 30 is carried on a pair of ball screws 32 similar to 45 the way unloader forks 29 are carried on their ball screws 31. Crank 30b pivots relative to frame 30d under urging of cylinder 30c thereby moving tines 30a relative to frame 30d, see Fig. 3D. Once freed from the burden 50 of stack 28 by feeder assembly 30, the unloader forks 29 can lower to receive another stack 28. The lifted stack 28 is set at a level for feeding strip into the press by means of raising the feeder assembly 30 as necessary. 55 Schematic Figs. 3, 3A, 3B, 3C and 3D show the various states of operation of the unloader forks 29 and feeder assembly 30. In Fig. 3, the unloader forks 29 are commencing to raise the first stack 28 of strip stock from 60 pallet 27. The raised position is shown in Fig. 3A, and is shown in its feeding position in Fig. 3B. A pair of sensors for high and low level are designated 33 and 34 respectively. High level sensor 33 is responsible for stopp-65 ing the unloader forks 29 at their uppermost position and low level sensor 34 for raising the stack 28 to the high level. The sensors 33 and 34 can be of a photoelectric variety or of a limit switch type. The strips of stock are lifted from the top of the stack 28 by suction cups 35 to a magnet 36 and hence the level of the top of the stack decreases, until ultimately the sensor 34 is tripped causing the elevator mechanism 25 to raise the unloader forks 29. In due course, the stack 28 will have diminished to the point where the unloader forks 29 are in line with the bottom position for the feeder fork 30. Then the feeder fork 30 extends under the stack 28 and lifts same from the unloader forks 29. Thereafter feeder fork 30 feeds the stack 28 until the low level sensor 34 no longer senses a strip at which point the strips remaining in the depleted stack are held by spring loaded fingers 37 as will be explained later. Then the feeder fork assembly 30 is freed to move downward and retract so that the unloader forks 29 can lift another stack 28.

Limit switches are provided to control the position of the stacks 28. More particularly, in Fig. 3 the pallet 27 is moved along conveyor 24 until limit switch 38 is closed at which point the conveyor stops. Similarly, unloader forks 29 are raised until limit switch 39 is closed, as depicted in Fig. 3A, and finally limit switch 40 is connected to spring fingers 37 such that a signal is transmitted when spring fingers 37 have moved to support the remaining stack 28, Fig. 3. In operation the limit switches 38, 39 and 40 coact to control the supply of strip available to the suction cups 35.

By means of unloader forks 29, feeder assembly 30 and/or the spring loaded fingers 37, a supply of strip is continuously maintained at a level between the high and low sensors 33 and 34. More particularly, the feeder assembly 30 as previously explained pushes the stack 28 up between the spring loaded fingers 37 (as shown in Figs. 3A and 3B). Each spring 37 is mounted to slide in a channel 41 which permits the top portion of each to be biased towards the stack. When the stack diminishes to a few remaining strips (as shown in Fig. 3C) the spring loaded fingers 37 which were riding against the sides of the stack 28 (Figs. 3A and 3B) are now urged by springs 42 to slide within channel 41 underneath the stack 28 to retain them against downward motion when the feeder assembly 30 is lowered and retracted to a position for receiving a new stack. Spring fingers 37, including an upper land 37a thereof adapted to reach underneath the bottom of the remaining stack of strips 28 (as shown in Fig. 3) then carry the remaining strips.

Magnets 36 are horizontally disposed above the stack 28 and are arranged with a surface in a plane slightly above the "tin line" within

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the press. Consequently, as vacuum cups 35 are reciprocated vertically to lift the top strip off the stack 28, the magnets 36 act to retain the lifted strip so that the suction cups 35 can 5 release it. Lifting an individual strip is assured by means of pickers 43 arranged and supported slightly above the stack and extending normally into the path through which the vacuum cups 35 pull the top strip toward the 10 magnets 36. Each picker 43 is an acerous protuberance which frictionally contacts an edge of the strip in order to assure that a second strip is not carried along therewith. More particularly, the pickers 43 engage the 15 top strip with a force insufficient to overcome the pull of the suction cups 35 but adequate to separate the top strip from any underlying strip that may inadvertently stick to it. The pickers 43 thus tend to fan the edges of 20 sticking strips much like a deck of cards are fanned to separate them during shuffling.

An inserter mechanism 26 is located above the top of the stack 28 from which strips are lifted to the magnets 36. The inserter mecha-25 nism 26 pushes strips laterally into a strip feed mechanism 45 (see Figs. 3, 3A, 3B and 3C). Inserter mechanism 26 includes guide rod 46 horizontally disposed above the magnets 36 and in general alignment parallel 30 thereto such that a sliding bushing 47 may ride on each guide rod from a first position away from the strip feed mechanism 45 to a second position near strip feed mechanism 45 (see Figs. 3B and 3C). Slide bushing 47 35 carries a downwardly extending tab 48 enga-geable with the edge of a strip carried by magnets 36 for pushing the said strip across magnets 36 to the strip feed mechanism 45 as best shown in Figs. 3B and 3C. The slide 40 bushings 47 are moved in timed relation by drive links 49 which reciprocate in timed relation to the needs of the press for strips to be formed. More particularly, in Fig. 2 drive links 49 are shown attached to a pair of 45 connecting rods 50 which oscillate about a drive bar 51 by an arm 52 connected to a power cylinder 53. Similarly, vacuum cups 35 are raised and lowered by a pair of arms 54 which are supported on a drive bar 55 which 50 is oscillated by a cylinder arm 56 moved by a power cylinder 57. Bars 55 and 51 are horizontally disposed and rotatably supported between upstanding vertical grunnions 58. Each grunnion 58 is carried on a cover 59 for the 55 strip feed mechanism 45 and the cover 59 is hingedly mounted to the strip feed mechanism 45 by a pair of hinges 60. The hinges are located on the side of the feed mechanism 45 opposite that where the strips are inserted. 60 As shown in Fig. 1, shaft 19 has a jack shaft extension 19a connected to its end opposite the clutch 18. The jack shaft extension 19a drives a pulley and cog belt system 61 including lower cog pulley 62 which is 65 attached to the jack shaft extension 19 a. The system 61 is operative to rotate an upper cog pulley 64 supported on an upper cog pulley axle 63 mounted to the exterior side of frame 12 about which the upper cog pulley 64 can 70 idle. A cog pulley belt 65 connecting the pulleys 62 and 64 acts to turn the upper cog pulley 64 at a speed which is slower than the smaller, lower cog pulley 62. On the face of the upper cog pulley 64 is a diametrically 75 positioned face groove for adjustbly driving a movable connecting link 66. More particularly, an adjustably positioned axle 66a is arranged to mount within the face groove 64a at a predetermined position spaced from the 80 center of axle 63. Varying the spacing between the axes of axles 63, 63a varies the distance of travel of link 66. Connecting link 66 moves to and fro in a generally horizontal plane when cranked by rotation of the upper 85 cog pulley 64. The end 66£>of connecting link 66 remote from the axle 66a is pivotally joined to an oscillating arm 67 which extends upwardly to a drive shaft 68 in Fig. 2. Drive shaft 68 is trunnionly supported for rotation in 90 a horizontal attitude along side 12 of the press frame. At the end of drive shaft 68 remote from the oscillating arm 67 another feed arm 69 is connected, arm 69 extending upwardly from drive shaft 68 to a feed drive 95 rod 70. Rod 70 extends away from the press parallel to feed mechanism 45. The rod 70 is positioned beneath the feed mechanism 45 to transmit the motion imparted by arm 69 thereto. Feed drive rod 70 oscillates toward and 100 away from the press. The throw of feed drive rod 70 can be varied by adjusting the position of the adjustable axle 66a relative to the axis of axle 63.

The feed drive rod 70 is connected to a 105 guide block 71 (Fig. 3) which is supported by guide ways 7 2 forming part of the feed mechanism 45 (see Fig. 2). The throw of rod 70 is assured of being controlled in and out motion which is transferred from the guide block 71 110 to a drive bar 73 mounted thereto at one end and having a threaded connection at the other (see Fig. 2). The drive bar 73 passes through a connecting block 74 which acts to adjustably support a pawl bar 75 (Fig. 2) so the 115 respective positions of the drive bar 73 and the pawl bar 75 can be adjusted relative to one another by means of their threaded ends. The pawl bar 75 is carried in a guide slot 45a (Figs. 3, 3A, 3B and 3C) for controlled reci-120 procaton toward and away from the press. Carried on the pawl bar 75 are a number of -pawl pivots 76, each horizontally disposed and extending outwardly from the side of the pawl bar 75 (Fig. 4). Each pivot rotatably 125 mounts a pawl 77 adapted to extend upwardly from the pawl bar 75 (as shown in Figs. 3, 3A, 3B, and 3C). In order to urge the pawl 77 upwardly about its pivot 76 each pawl includes a pawl spring 78 (see Fig. 4). 130 In Fig. 4 the processing of a strip of stock

28a is shown as it moves from the feed mechanism 45 transversely through the lubricating area into the first station of the press die where it is blanked and cupped and a 5 skeleton 286 is left. Each strip 28a is lubricated in the area between the feed mecha-' nism 45 and the first station of the press die. More particularly, a bracket 11a which hangs downwardly from the crown 11 of the press 10 supports lubricating mechanism which includes an upper lubricating pad assembly 81 and a lower lubricating assembly 82. Between bracket 11 a and assembly 81 is a support bracket 79 which has a bushing 79a disposed 15 to receive a support 84 for the upper pad assembly 81. More particularly, support 84 consists of a hub shaped portion 84a and a cylindrical rod 846 extending outwardly therefrom. The cylindrical rod 84b is designed to 20 cooperate with bushing 79a to permit controlling linear motion along an axis normal to the surface of the strip 28a. The hub portion 84a includes a flanged end having manifold passages and support means for a lubricating pad 25 83 which is composed of absorbent material designed to spread the manifolded lubricant across the contact surface of pad 83 such that a predetermined spot of lubricant can be applied to the upper surface of the strip 28a 30 when the moistened pad 83 is pressed against it. The movement of the assembly 81 is controlled by a power cylinder 86 which is mounted between bracket 11a and a lever 87 pivotally mounted at 87a to a portion of 35 bracket 11 a. On the ends of power cylinder 86 are clevis connections to permit limited arcuate motion in planes through said connections. More particularly, the top of cylinder 86 has a clevis 86a attached to bracket 11a and 40 the bottom of cylinder 86 has a clevis 866 arranged to connect to one end of lever 87.

Pivot 87a is near the middle of lever 87. The other end of lever 87 is yoke-shaped and is apertured for receiving pivot pins 85 ex-45 tending from the hub portion 84a of the pad assembly 81. Power cylinder 86 includes a piston 86 d which is activated by air pressure transmitted to the bore of the cylinder 86 in timed relation to the intermittent motion of 50 the strip 28a as it pauses in the lubricating area. Above piston 86 d is a return spring 86 c which is designed to cause the piston 86tf to move downwardly in the bore when the air pressure is released. When the air pressure is 55 admitted to the bore the piston 86d rises thus moving the pad assembly 81 downwardly toward the surface of the strip 28a.

The lower pad assembly 82 is similar in operation and parts which are identical have 60 similar numbers to those used in connection with assembly 81. Instead of a power cylinder to move the assembly there is a bell crank 89 supported for pivotal movement by a pillow bearing 88 attached to the bottom of feed 65 mechanism 45. Feed mechanism 45 is supported by bracket 126. Crank 89 has a short leg 89a and a long leg 896. The short leg 89a extends generally upward from the pivot axis of the crank 89 and includes a roller follower 89 c which rides against a pawl bar cam 75a. The elongated leg 896 of crank 89 extends generally horizontally toward the pivots 85 on the hub 84a of the lower pad assembly 82. Thus as the feed mechanism 45 shuttles strip into the press, the movement of the pawl bar 75 causes cam 75a to move crank 89 to reciprocate lower pad assembly 82 along its support rod 846 carried within a bushing 80a on a bushing bracket 80.

Bracket 80 is affixed to and carried by feed mechanism 45. Beneath the long leg 896 of crank 89 is a bracket 90 housing a compression return spring 90a in a bore in the bracket, the spring being retained by a cup-shaped spring cap 906. The spring bears on crank 89 and consequently the follower 89c is urged by spring 90a against the cam 75a.

Extending downwardly from spring bracket

90 is a pump bracket 91 which includes an adjustable, laterally-extending pump support

91 a set bearing a positive displacement pump 92.

Two American Bosch Corporation injection pumps type No. PLB1A-60A-2326-A have been found to perform satisfactorily in this applicaton. Each pump 92 is mounted so that its activating portion extends downwardly from bracket extension 91 and its supply and return connection extends generally upwardly therefrom. More particularly, oil is supplied to the pumps through tubes 92a and is pumped through tubes 926.

One of the tubes 926 connects to lower pad assembly 82 and the other to upper pad assembly 81. The tubes are of a flexible material such that the reciprocal motion of the pad assemblies can be accommodated. A supply reservoir 92c, shown in Fig. 2, is located above and adjacent bracket 11 a. To activate the injection pumps there are pump drive bars 93 which are carried in separate parallel vertical bores of a drive bar support block 94 which is mounted to the press slide 15. More particularly, as the press slide 15 moves upwardly it carries the drive block 94 with it and when the pump drive bars 93 are in the position shown in Figs. 4 and 4A, the injection pumps 92 are activated.

It should be appreciated that it would not be desirable to activate the pumps 92 when there is no strip 28a in the course of being delivered from the feed mechanism 45 to the lubricant area. To this end, in order to lower the drive bars 93 such that they are out of the range of the pumps 92, when the press slide 15 reaches the top of its stroke there is a movable shuttle 95 supported in a transverse tunnel 94a in block 94. The shuttle 95 is activated by a solenoid 96 mounted at one end of block 94 and arranged to pull the

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shuttle 95 against the urging of a tension spring 97. Spring 97 is connected at one end to a pin 95a which extends downwardly from the shuttle 95 and moves therewith and at its 5 other end to a pin 94c extending upwardly within block 94. Solenoid 96 is connected to the shuttle 95 by a clevis connection 96a and is activated by means of a sensor 966 located above the bed of the feed mechanism 45 near 10 the lubricating area for sensing the presence or absence of the strip 28a. When sensor 966 detects a strip 28a, a current is applied to the solenoid such that the shuttle 95 is drawn toward the solenoid 96 (against the urge of 15 the spring 97) and the drive bars 93 are raised to their highest position.

Drive bars 93 are carried non-rotatably in a bore 946 in the block 94 for movement vertically. In Fig. 4A, pins 93a are shown 20 fixed to the block 94 and each extending through a slot in its respective drive bar 93. At the bottom of each drive bar 93 is a cam ramp 936 which is cooperable with a similar ramp 956 on shuttle 95. When the solenoid 25 releases the shuttle 95, spring 97 urges the shuttle away from the solenoid 96, thus aligning ramps 936 and 956 permitting the drive bars 93 to drop relative to support block 94 to a position in which they are unable to 30 contact the pumps 92 and supply the energy necessary to force the oil along the supply tubes 926. As is apparent from Fig. 4A, there are two pumps 92, one for the upper asembly 81 and another for the lower assembly 82. 35 The shuttle 95 is arranged to control both pump drive bars 93 and thereby eliminating oil pumping when a strip 28a is not in position to be lubricated.

Fig. 4 shows the first die station of the 40 press in a rather schematic form; the details of the press dies will be explained in connection with other figures. It will be sufficient to say that the strip 28a is blanked leaving holes therein and a remaining skeleton 286 which 45 proceeds across the press and into a scrap removal device. More particularly, there is a scrap drive support 98, shown in Fig. 4 and also in Fig. 1. In Fig. 1 the support 98 is mounted on scrap drive support hinge pivots 50 12a affixed to the side 12 of the press frame. The pivots 12a carry a scrap hinge pin 98a which is designed to carry support 98 so that it can be rotated into its operating position or away therefrom as needed during operation 55 (Fig. 4) or servicing (Fig. 1) of the press.

In Fig. 4, support 98 is shown in its operating position. On support 98 there is an upwardly extending roller support bracket 986 which is arranged to carry a pivot for an 60 upper roller bracket 100 whereby an upper, elongated cylindrical roller 101, is able to rotate thereon and pivot from a position bearing against the scrap skeleton to position away from the scrap skeleton 286. The sup-65 port 98 also includes a lower roller support

98 c which carries a lower roller 102 in a position beneath the upper roller 101 so that they may be juxtaposed with their axes parallel to one another. The upper roller bracket

100 is connected to a scrap power cylinder

99 which at one end 99a is connected by means of a clevis to the support 98 and at the other end 986 is connected by a clevis to an extended part of bracket 100. Operation of power cylinder 99 will move roller 101 away from or toward roller 102. The surface of roller 102 has knurling in order to provide a tractive surface to drive the scrap skeleton 286 out of the nip between the rollers 101 and 102 when juxtaposed, and out of the press.

A motor and drive belt 103 is mounted on support 98 to drive lower roller 102 in clockwise fashion, (as seen in Fig. 4). The operation the power cylinder 99 is used to bring roller 101 down upon the scrap skeleton 286 such that the rotating roller 102 will drive the scrap skeleton 286 out of the press in timed relation to the shifting of the next strip 28a. Roller 101 acts as a follower and rotates counterclockwise when subjected to the driving force transmitted by lower roller 102.

Fig. 5 is an enlarged side elevational view showing a partial cross-sectional view of the die and transfer mechanism for the press. All of the drawing and redrawing stations in the press are shown with exemplary containers positioned as they would appear during the press cycle after the part has been formed and the transfer mechanism is just grasping same to begin transfer to the next station. The dies are located between the slide 15 and the crown 11. Attached to the crown 11 is a flat horizontally disposed bolster plate from which hangs the upper portion of the die set or punches. A number of spacers all labelled 105 are located throughout the die set and are used in order to adjust the positions of the various components for purposes of accommodating different die sets as needed for making containers of different sizes. That is to say, that by adjusting the size of the spacers 105, or by changing them, and by adjusting their relative positions, different punch and die arrangements can be used between the slide 15 and the bolster plate 104.

The press die set is controlled by a leader pin guide system. A punch shoe 106 is shown supporting leader pin 107 on the left side of Fig. 5. On the right side the leader pin

107 has been partially cut away in order to better display certain aspects and features of the press. The strip 28a, as shown in Fig. 4, is fed to the initial station 108 for blanking and cupping in Fig. 5 by shifting the strip 28a one cut edge plus a scrap allowance with each stroke of the press. The initial station

108 for blanking and cupping includes a preliminary die 109 which severs a blank or

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disc of metal of a predetermined diameter from strip 28a.

Preliminary die 109 moves upwardly with each stroke of the press slide 15 about a 5 stationary pedestal 110 concentrically located within blanking and cupping die 109. Pedestal 110 is supported at a height where its top surface meets the bottom of the drawn cup and holds same in contact with the said 10 surface so that the flange thereof is in a predetermined plane slightly below the tin line. Pedestal 110 is supported by a base cavity support 14a which rises up from the bottom of the press through an opening in the 15 slide 15. Support 14a is fixed and does not move with each stroke of the press, so that the pedestal 110 is always positioned to receive blanked and drawn cups e.g. formed in the initial station 108 for blanking and cupp-20 ing.

Above pedestal 110 is the initial station punch and hold down 111. In a manner well known the punch and hold down 111 is resiliently biased downwardly toward the tin 25 line. As the preliminary die 109 is raised by the slide 15, it first severs a blank against the force of the punch and hold down 111 then continues to draw the severed blank upwardly about the punch as the hold down controls 30 the feeding of material from the flange area into the walls of the cup. The biasing of the punch and hold down are different and are adjusted in accordance with the desired result, i.e. an unwrinkled flange and a smooth un-35 scored cup wall. After the die 109 has reached the top of its stroke it begins to descend bringing with it the formed cup which is brought to bear upon the top of pedestal 110. The die 109 continues to de-40 scend about the pedestal 110 leaving the cup atop the pedestal. Although not shown, it may be desirable to include vacuum passages or magnets in the top surface of the pedestal 110 to ensure that the workpiece cup will not 45 shift relative to its centered position on its pedestal until it is desired to do so. If a vacuum system is provided, it can be used as a monitor responsive, by way of pressure or air flow detecting means, to air entering the 50 system when a workpiece is absent from a pedestal or is improperly seated thereon. The monitor can be used to give an alarm or to halt the machine.

The said detecting or control means are 55 desirably timed to respond to the presence or absence or displacement of a workpiece before the transfer mechanism to be described has performed a transfer operation and after a workpiece has been captured between the 60 upper and lower tooling.

In an effort to simplify the discussion of the dies, the explanation on how the cup is transferred so that its axis is aligned with the axis of the next forming station called the first 65 redraw station will be delayed until later. It will be assumed that such transfer takes place and the mechanism for doing so will be explained in detail in connection with Fig. 6. For the moment, the explanation of the prog-70 ressive drawing and redrawing of the initially formed cup will proceed without further explanation of the transfer mechanism details. In the first redraw station 112 the cup is held in position with its flange slightly below the tin 75 line of the press. As the slide 15 is raised a first redraw die 113 comes up and meets the bottom of the cup which has a diameter larger than the diameter of the first redraw die 113. Consequently, the cup is pressed upwardly 80 against a punch and hold down for the first redraw 114. The first redraw punch and hold down 114 is supported in axial alignment above the die 113 by the bolster plate 104 and a spacer 105. There is a stationary pedes-85 tal 115 axially aligned with punch 114 and die 113 and is carried upon support 14a. Pedestal 115 is designed to receive the cup after it is redrawn in the first redraw station 112 where it becomes longer and thinner. 90 More particularly, the first redraw die 113 is raised with the stroke of the slide 15, pressing the bottom of the cup upwardly towards the hold down and punch 114 and redrawing the cup to an elongated container in accordance 95 with the configuration of the first redraw punch 114. After the top of the stroke is reached, the die 113 descends carrying with it the redrawn container toward the top of pedestal 115 where it is held in a manner 100 similar to that described for pedestal 110. As the slide 15 approaches the bottom of its stroke the redrawn cup is transferred to the next station in the press where the second redraw and bottom profiling take place. 105 The second redraw and profiling station

116 includes a second redraw die 117 and a bottom profile die 118. The redrawn cup has a larger diameter than the second redraw die

117 and is captured between the redraw die 110 117 and a second redraw punch and hold down 119 as the slide 15 moves upwardly. The second redraw punch and hold down 119 are carried by the bolster plate 104 and a spacer 105 in axial alignment with the axis of 115 the second redraw die 117 and the bottom profiling die 118. As the stroke of the slide 15 continues the second redraw die 117 in cooperation with the second hold down and redraw punch 119 stretches and elongates 120 the container to the configuration of the punch in a manner similar to that of the first redraw die set 112. As the stroke is completed the second redraw die 117 reverses its direction and brings with it the redrawn con-125 tainer placing same upon a hollow pedestal support 120.

Pedestal support 120 is carried by spacer pedestal 105 at the proper height to assure that the flange of the formed container is 130 maintained near the tin line. Hollow support

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pedestal 120 is adapted to permit a profile die to reach the bottom of the container as the slide 15 moves upwardly during its stroke. For that purpose the hollow support 5 pedestal 120 has an opened longitudinal slot as shown in Fig. 5 and labelled 120a. The slot 120a is arranged to permit a part of the die 117 to connect with die 118 whereby profile die 118 is carried along with the 10 second redraw die 117 during the second redrawing operation.

The container is then transferred so that its axis is in alignment with the next station called the flange trimming station 121. Here 15 the flange is severed to a preset diameter concentric to the axis of the redrawn container. The flange trimming die 122 is secured about a support pedestal 124 and in axial alignment with the axis of the container 20 and the flange trimming punch and hold down 123 which is supported just above the tin line. As the press slide 15 moves upwardly the flange trimming die 122 is brought to bear against the bottom of the flange raising 25 same against the hold down and trimming punch which severs the flange leaving a ring of scrap to descend with the trim die 122. A pair of rails 125 are horizontally disposed close alongside the the container in position 30 to catch the descending scrap ring while the trim die 122 continues its descent. The details of the cooperating moving relationship of the rails 125 and the trim dies 122 will be described hereinafter in greater detail in con-35 nection with Figs. 7 and 8.

The container is then transferred to the next discharge station having a lifter 126, which includes a platform for raising the container to a magnetic discharge conveyor 130. More 40 particularly, the container and the circumscribing scrap ring are lifted by the discharge lifter 126, and air jets 127 in Fig. 5 are directed toward the bottom of the container to maintain the scrap ring in position about the 45 container at a level not below an upper guide rail system 128. The guide rails 128 are spaced apart sufficiently to permit the containers to pass therebetween but close enough to carry the scrap ring 129 so that it does not 50 fall from the container as the container is moved out of the press by magnetic conveyor 130.

Magnetic conveyor 130 includes a belt 130a which is caused to pass beneath mag-55 nets 1306 by a drive system 130c. The belt material is permeable to the magnetic flux whereby the remaining flange on the container is attracted to the belt to be removed therewith out of the press. At the end of rails 60 128 opposite the discharge lifter the scrap ring 129 is permitted to drop but the container is conveyed further by the magnetic conveyor 130 to another container conveyor system, not shown.

65 One other detail shown in Fig. 5 is the driving system for the slide 15. More particularly, attached to the bottom of the slide 15 are downwardly depending trunnions 15a to receive the top part of crank arms 132. The trunnions 15a are connected pivotally to the crank arms 132 by wrist pins 131. Crank arms 132 extend downwardly to the crank and reciprocate the slide 15 as will be understood.

Fig. 6 shows the mechanism for transferring the container from its initial blanking and cupping station 108, and serially through first redraw station 112, second redraw and profile station 116, redraw flange trimming station 121 and finally to the discharge lifter 126. The mechanism consists of a series of finger sets which are arranged to pivot toward one another in order to grasp the container about its circumference below its flange and for transferring it from one station to the next.

Referring to Figs. 5 and 6, transfer mechanism 133, which is shown in plan view in Fig. 6, includes two oscillating systems, one to transmit motion to the finger sets and one to move the entire transfer mechanism 133 sufficiently to place the finger sets in alignment with a first station to receive a partially formed container and a second station to release the partially forming containers for further forming. More particularly, there is a dual reciprocating drive 134 (Fig. 5) which includes transmission 135 that imparts a reciprocating angular motion to an oscillating arm 136. Arm 136 is driven about an axle 135a by a hollow oscillating shaft (not shown) also connected to transmission 135. The axle is also arranged to drive a rotary edge cam 137 independently of the oscillating arm 136. The edge cam 137 is positioned just above the arm 136. A bell crank having a short leg 138 is provided with a roller follower 138a set to trace and follow the edge of cam 137 as same is rotated. The short leg 138 is attached to a long leg or cam lever 139 at a pivoting point 136a mounted on the oscillating arm 136 whereby the lever 139 oscillates as a result of motion imparted to it by short leg 138 and by pivot 136a.

A shock damper 140 is connected to approximately the midpoint of lever 139 by means of a clevis 140a. In a manner common to a reciprocal device shock damper 140 acts to restrain any harmonic motion induced by the frequent velocity changes imparted to lever 139 during its oscillation. The driven lever 139 and arm 136 are connected to -additional linkage for the transfer mechanism 133. Connected to lever 139 is a drive rod 141, and connected to arm 136 is a transfer rod 142, see Fig^ 6C. Both rods 141 and 142 feature a turn buckle construction so that the distance between the driving and the driven rods can be adjusted to a preferred length. Transfer rod 142 is connected to drive a chassis 143, see Figs. 6, 6B and 6C, in

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reciprocating linear fashion. Chassis 143 is supported on the press crown 11 for controlled motion, the details of which will be explained later in connection with Fig. 6B.

5 Chassis 143 carries with it slide bars 144 such that they may act to guide a finger block 145 driven for independent movement by drive rod 141. Consequently, the different reciprocations of the drive ends of lever 139 10 and arm 136 are imparted to interdependent systems. More particularly, they are interrelated to move linearly but they are independent in that the movements are not of the same periodicity or distance. Such motion is 15 required in order to shift the finger sets to permit the transfer and in order to provide the opening and closing of the finger sets for purposes of grasping and releasing the container at the required times. The motion im-20 parted to the finger block 145 is transferred to finger arms 146 which are mounted on pivots 143a carried on the chassis 143. The arms 146 are connected to drive finger-oper-ating bars 147 for purposes of supplying the 25 relative independent motion as necessary for opening and closing the finger sets.

The chassis 143 is supported for limited horizontal sliding by means of transfer support guides 148 which lie in guide ways 116 30 depending from the crown 11 of the press. The guides 148 track along the ways 11 b such that the motion of the chassis 143 is linear, planar and horizontal relative to the press. More particularly, the motion of the 35 transfer mechanism 133 is in a plane parallel to and close by the tin line.

The finger-operating bars 147 are attached to drive finger bell cranks 149 which are supported on crank pivots 149 a depending 40 from the transfer support guides 148. The relative difference in reciprocating motion imparted to the finger operated bars 147 and the transfer support guides 148 is manifested in an arcuate movement of the inner leg of 45 the bell crank 149. Attached to the inner leg of each bell crank 149 is a light weight transfer finger 150. The transfer fingers 150 are preferably molded of a polymeric material to minimize their inertia (particularly in the 50 distal portion 150a which is shaped to meet and grasp the container). There are a pair of fingers 150 in each finger set, such that they are able to move arcuately toward or away from one another under the swinging action 55 of the bell cranks 149. In order to shift the partially formed and reformed containers there are four sets of fingers, each set is adapted to grasp and move a particular size container. The relative spacing of the finger sets and in 60 particular, the shaped distal portions 150a when they are in their closed or container-holding position is a function of the length of the fingers 150 in a set and their elongation relative to the inner leg of their respective bell 65 cranks 149. Consequently, by merely changing the fingers 150, the transfer mechanism 133 can be adapted to grasp, shift and release the various size containers (throughout their range of drawn and redrawn configura-70 tions). In Fig. 6B the cross-sectional details of the drive for the chassis 143 and its attachment to the finger operating bars 147 are shown as are the mountings of the transfer support guides 148 in their respective guide 75 ways 11b. Similarly, Fig. 6A shows the details of how the finger operated bars 147 drivingly connect to the finger bell cranks 149.

Catching the scrap ring 129 is the function 80 of a mechanism 151 detailed in Figs. 7 and 8. The transfer mechanism 133 shifts partially formed containers from alignment with the axis of one tool station to the axis of the next tool station. Fig. 7 is an elevational view 85 taken transversely through the press just upstream of the flange trimming station 121. The mechanism 151 moves the lower scrap guide rails 125 to and from the axis of the container. More particularly, the lower guide 90 rails 125 are cammed in and out to enable them to catch the scrap and clear the trim die 122. The rails 125 are supported on rail support rods 125a which are bushed in pillow blocks 152 supported by brackets 11 c de-95 pending from the crown 11. To move the flange scrap guide rails 125 in and out relative to the axis of the die 122, clevis-shaped followers 153 are connected to the ends of the rail support rods 125a at the ends oppo-100 site the rails 125. Followers 153 carry rollers

154 between their arms, the rollers riding against two linear cam tracks 155. The tracks

155 are mounted vertically atop the slide 15 and move with slide 15. As the slide 15

105 moves upwardly it carries the linear cam tracks 155 upwardly between the arms of the clevis followers 153 and vertical motion of the tracks is translated into horizontal reciprocating motion of the rollers 154, the clevises 110 153, the rods 125a and the guide rails 125 toward and away from the axis of the flange trimming die 122. The timing of the reciprocal horizontal motion of the guide rails 125 is such that as the flange trim die 122 is low-115 ered the scrap 129 carried therewith is caught by the guide rails 125 since they move inwardly toward the flange trim die 122 at the same rate as it is lowered whereby the scrap ring 129 lands on the rails 125. For the 120 purposes of assuring that the roller 154 follows closely the contours of the linear cam track 155, there are tension springs 156 strung between the clevis 153 and the bracket 11c. Springs 156 maintain a rolling 125 relationship between the rollers 154 and the cams 155 by pulling the rollers 154 toward the cams 155. As already set forth the rails 125 retain the scrap ring 129 in position about the circumference of the container so 130 that the scrap ring 129 is carried with the

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container as same is further processed. Gravity will act to separate the ring 129 easily from the container as the container leaves the press. Also shown in Figs. 7 and 8 is the 5 leader pin 107 and its support or punch shoe 106.

Claims (1)

1. A mechanism for distributing work-10 pieces through a forming machine wherein the workpieces are progressively shaped into articles of desired shapes in a plurality of forming stations, the mechanism continuously maintaining a portion of each workpiece in a 15 common plane and including a supply means for presenting individual sheets of thin work-piece stock for blanking in a first of the forming stations which have central axes about which workpieces are blanked and 20 formed during operation of the machine, a first support means axially aligned with the first station and spaced from the common plane by the depth to which the article is formed to maintain a portion of the semi-25 finished article in the said common plane, an advance mechanism operative in a plane parallel to and adjacent the said common plane for displacing the semi-finished article from the first station to another forming station 30 while maintaining a portion of the article in the common plane, another support means opposite the latter forming station and spaced apart from the common plane by the depth to which the article is formed therein to maintain 35 a portion of said article in said common plane, and further support means similarly associated with respective further forming stations to which the advance mechanism progressively transfers semi-finished articles, each said fur-40 ther support means being arranged to maintain a portion of the formed article in the common plane.

2. The mechanism according to claim 1, for use with a machine for producing drawn

45 and redrawn metal cans, wherein the said common plane is horizontally disposed and each of the said support means is vertically displaced downwardly from the said common plane to maintain the open ends of semi-50 finished cans level with the said common plane.

3. The mechanism according to claim 2, wherein at least two first-mentioned support means include retaining means which mate

55 with the bottom of a semi-drawn can to hold it until the advance mechanism operates to displace the said can towards the further support means.

4. The mechanism according to claim 1, 2 60 or 3, when incorporated in the forming machine wherein such forming tooling is located above the common plane to engage the upper part of said semi-finished articles when reciprocal lower forming tooling moves upwardly

65 about the support means to form the articles.

5. The mechanism according to any of claims 1 to 4, wherein the support means include monitoring means carried thereby in a surface thereof to detect the presence or ab-

70 sence of a semi-formed article.

6. The mechanism according to claim 5, wherein the said monitoring means is in a vacuum system which retains a workpiece against the upper surface of the said support

75 means, the absence of a workpiece thereon permitting air flow into the said vacuum system, which flow can be detected by pressure responsive controls connected to the said vacuum system.

80 7. The mechanism according to claim 6, wherein the pressure responsive controls are timed to respond before the said advance mechanism has transferred a workpiece from one of the support means and after the period

85 of time when the can is captured by the forming tools of the machine.

8. The mechanism according to any of claims 1 to 7, wherein said support means are interchangeably mounted about said lower

90 forming tooling of the machine to facilitate changing the relative vertical positioning of their workpiece supporting surfaces to accommodate various depths to which workpieces may be formed by the machine.

95 9. The mechanism according to any of claims 1 to 8, wherein said advance mechanism is timed to move semi-finished articles from one support means to another in the period between forming by tooling at one of 100 said stations and forming by tooling at another of said stations.

10. A method of transferring workpieces in a cyclically-operable press for progressively forming therefrom articles receiving some 105 elongation during forming, the method including the steps of: (a) feeding workpiece material to be formed into the press in a given plane; (b) pressing a portion of the material away from the said plane and toward a fixed 110 support until contact occurs therewith, while at the same time retaining a portion of the material in the said plane; (c) holding the formed material representing a semi-finished article against the fixed support for a specific 115 time period related to the cycling of the press; (d) grasping the said semi-finished article about a part thereof adjacent the said plane and moving the article, while keeping the said part in the said plane, a predetermined dis-120 tance to another forming station; (e) repressing the semi-finished article away from the said plane and toward a second fixed support until contact therewith is made; (f) retaining the said article against the second support to 125 maintain the said part of the article in the plane until movement thereof to further forming station; and (g) progressively pressing, retaining and moving the article until the desired final form is obtained while always 130 maintaining the said part of the progressively

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formed article in the said plane by means of fixedly located supports and by controlled movement of the article.

11. The mechanism for distributing work-5 pieces through a forming machine wherein the workpieces are progressively shaped into articles of predetermined shape in a plurality of forming stations, substantially as herein described with reference to and as shown in 10 the accompanying drawings.

12. A can making machine embodying a mechanism according to any of claims 1 to 9 or 11.

13. A method of transferring workpieces 15 in a cyclically-operable press from one forming station to another, substantially as herein described with reference to the accompanying drawings.

Printed for Her Majesty's Stationery Office by Burgess & Son (Abingdon) Ltd.—1981.

Published at The Patent Office, 25 Southampton Buildings,

London, WC2A 1 AY, from which copies may be obtained.