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Title: Product transfer system
Description: Description:
BRIEF SUMMARY OF THE INVENTION Beer and beverage cans of the so-called two-piece type are currently being produced by the drawn and ironed method and are quickly replacing the conventional three-piece can which has soldered side seams. Since the emphasis now is placed on the creation of sanitary cans for use with food products, the two-piece can has less chance for leaks and is more appealing aesthetically. Furthermore, legislation is being planned, not only in this country but also in foreigh countries, to eliminate the lead from the solder used in the side seam and ultimately to prohibit the use of tin as well. These prohibitions of course would be for health reasons. Two-piece sanitary cans are now in commmercial production and present systems rely on the use of a first operation cupping press, accummulators and unscramblers and a conveyor to feed the first operation cup into a multi-out redraw and trim press. The redraw and trim presses employ a transfer device called "finger bars." These finger bars are actuated by cams driven by the crank of the press and they move the cup from one station to the next and retract. They are oscillatory in nature. They are quite complicated and because of their mass the ultimate speed of the press is limited. For these reasons the presses are usually arranged as multi-out presses and operate at slow speeds in order to achieve the required production rates. If something breaks or otherwise fails in the transfer system, the tools close on the fingers resulting in damage not only to the fingers but to the tools. Since two-piece cans are generally blanked and drawn from coil or strip stock and are subsequently redrawn one or more times in order to reduce the diameter while increasing the can height, the present invention relies upon the reduction in diameter to make possible the use of an aerodynamic transfer device. Basically the part is first blanked from a strip and drawn downward through a draw die, thus creating a first operation cup which is relatively large in diameter and short in height. This cup is stripped from the tooling and is now disposed with its bottom on a pass line. The first operation cup is then moved to the first intermediate station by a flow of air. At the first intermediate station there are lateral stops of a size to prevent passage of the cup in its initial condition but to permit passage after it has been redrawn and its diameter reduced. Similar arrangements are provided at other intermediate stations. At the final station, the flange is trimmed and the completed can can then be discharged from the device. The stops at each of the stations are provided with vacuum openings so that the can is held firmly in position at these stations for the redrawing operation which there takes place. After the cup has been redrawn at any of the intermediate stations, a lifter is provided to lift it back up to a position where its bottom is on the aforesaid pass line so that it may be transferred to a succeeding station by air flow, or other suitable means. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS FIG. 1 is a diagrammatic horizontal cross sectional view showing the aerodynamic transfer arrangement and the several stops. FIG. 2 is a perspective view of the same. FIG. 3 is a diagrammatic cross sectional view taken on the line 3--3 of FIG. 1. FIG. 4 is a view similar to FIG. 2 but showing a two-out arrangement; and FIG. 5 is a fragmentary perspective view showing a modification of the arrangement at the right-hand end of FIG. 2. DETAILED DESCRIPTION At the outset it should be remarked that details of the blanking dies and the several different drawing dies and redrawing dies and their respective plungers are not shown. These are conventional and well known and understood by those skilled in the art. The invention is illustrated with an arrangement with four work stations. At the first station, a circular blank is punched out and this blank is drawn into a relatively wide and shallow cup. The circular blank is indicated in broken lines in FIG. 2 at 10 and the first operation cup is indicated at 11. The cup 11 after it has been drawn is stripped downwardly and ends up in a position shown in FIG. 3 with its bottom on a pass line indicated at 12. The die for forming cup 11 is indicated at 13 and the plunger at 14. The means for stripping the cup 11 have also not been shown because they are conventional. There is provided a channel 15 connecting the various stations and the channel is provided on its lateral sides with the air manifold 16. The manifold 16 communicates with the channel 15 by means of the acute angled passages 17. At the left-hand end of the channel there is an air connection 18. It will be seen that as soon as the cup 11 has been stripped and moved downward to the pass line 12, air entering at 18 moves the cup toward the right of the figures and it is then acted upon by air jets issuing through the openings 17 which continue to move it toward the right. At 19 are provided stops and preferably these stops are curved to fit the contour of the cup 11 before it is acted upon by the redraw punch and die at the first intermediate station. Vacuum is drawn through the tubes 20 so that the cup 11 is held securely in proper position for a redraw operation. As best seen in FIG. 3, in the redraw operation the cup is drawn to an elongated and reduced diameter condition indicated at 11a and as can be seen it is now positioned below the pass line 12. However, a lifting device which may be spring actuated or air actuated is provided at 21 to lift the redrawn cup 11a back to a position where its bottom is on the pass line 12. The cup is shown in this position in broken lines in FIG. 3. The smaller diameter is shown in FIG. 1 at 11a and it will now be seen that this smaller diameter is such that the cup can pass the stops 19 and continue to the next intermediate station where it is stopped by the stops 22. The stops 22 are similar to those at 19 except that they are curved to fit the reduced circumference 11a rather than the circumference 11. Again, vacuum is drawn by means of the tube 23 to hold the redrawn cup 11a in position for the next redrawing operation. This operation is shown in FIG. 3 and the cup is now in the condition indicated at 11b. This includes a bottom forming operation and again a lifter arrangement is provided at 24 to return the cup 11b to a position where its bottom is on the pass line 12. The raised position of the cup 11b is not shown in FIG. 3 but it is of course similar to the position of the cup 11a. It will be observed that the reduced diameter 11b is such as to permit the cup now to pass on to the final station under the influence of air through the port 17. In the embodiment of FIGS. 1, 2, and 3, the cup 11b comes against a stop 25 and the cup is held in position by vacuum drawn through the tubes 26. At this station the cup is trimmed and may then be discharged downwardly by conventional means as indicated at 27. The discharge of the completed redrawn cup may be as shown in FIG. 5 rather than downwardly as shown in FIG. 2. Thus, the stop 25 may be in two pieces 25a, which may be hinged apart so that air through the ports 17 can blow the completed cup out in the direction of the arrow when the stops halves 25a are opened as seen in FIG. 5. FIG. 4 shows a two-out arrangement of two structures according to FIG. 1. The two structures may be identical except that the first stations are offset from each other. The punches and dies of the two structures indicated generally at A and B operate at the same time. If the first stations were not offset there would be a considerable waste in the strip S in the blanking operation. However, if the first stations are offset as seen in FIG. 4 and the strip S is fed into the apparatus, when the two punches cut out the circular blanks 10 at the same time the holes will be positioned as seen at 10a in FIG. 4 and these are staggered so that scrap is minimized. FIG. 4 also illustrates why the first operation cup 11 is stripped downwardly. This is so that there is no interference with the passage of the strip S when it is advanced for a succeeding blanking operation. It will be clear that numerous modifications may be made without departing from the spirit of the invention and no limitation not specifically set forth is intended and none should be implied. Other info: Inventors: Kaminski, Elton G. (Sidney, OH, US) Application Number: 566294 Filing Date: 1975-04-09 Publication_date: 1976-03-02 Assignee: The Stolle Corporation (Sidney, OH) Primary Class(es): 413/78 72/349, 72/405.07, 406/86 Other Classes: US Patent Ref:
Other Refs: Primary Examiner: Mehr, Milton S. Assistant Examiner: Crosby, Gene P. Attorney: Melville, Strasser, Foster & Hoffman |
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