US 3425382 A
Description (OCR text may contain errors)
Feb. 4, 1969 T. s. JOHNSON 3,425,382
TAPERED, STACKING AND NESTING CAN Filed Feb. 9. 1967 Sheet of 3 INVENTOR.
' THOR E. JOHNSON F1r5- 2 BY ATTOR NEYS Feb. 4, 1969 T. E. JOHNSON 3,425,382
TAPERED, STACKING AND NESTING CAN Filed Feb. 9, 1967 Sheet 2 of 5 INVENTOR.
THOR E. JOHNSON BY (ya/l ATTOR NEYS Feb. 4, 1969 T. E. JOHNSON 3,425,382 I TAPERED, STACKING AND NESTING CAN Sheet 3 of5 Filed Feb. 9. 1967 INVENTQR.
THOR E. JOHNSON Y Z I B fij? ATTO R N EYS United States Patent 3,425,382 TAPERED, STACKING AND NESTING CAN Thor E. Johnson, San Francisco, Calif., assignor to M. J. B. Company, a corporation of Delaware Filed Feb. 9, 1967, Ser. No. 614,905 US. Cl. 113-120 Int. Cl. B21d 51/10 3 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION Field of the invention Manufacture of tin plated steel tapered cans having soldered seams.
Description of the prior art Tapered cans pose special production problems and the present invention provides an easy means of transfering a conical section from one center line to another. Heretofore this has required complicated machinery.
SUMMARY OF THE INVENTION In making cans, it is necessary to start out with a flat can body and convert this into a cylinder or a conical section. In the case of -a conical section, a seam must be formed on one center line yet it is impractical to move the can on this center line for a subsequent soldering operation. In the past, this has required a complicated manipulation but the present invention provides an easy means of transferring the conical can body from one center line to another by deforming one end of the can into an oval or ellipse wherein the larger diameter of the oval is equal to the diameter of the cylindrical, larger end of the can.
BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is a side view of a can embodying the present invention showing the lid detached therefrom.
FIGURE 2 is a section through a plurality of cans showing the method by which the cans nest yet do not wedge because of the beads thereon.
FIGURE 3 is an enlarged sectional view showing the method by which the cans stack when lids are on the cans.
FIGURE 4 is a plan view of a tapered body blank used in forming the can of the present invention.
FIGURE 5 is a diagrammatic view illustrating the sequence of operations of forming the can of the present invention.
FIGURE 6 is a side view of the body-forming operation showing by which the transfer from one center line to another is made.
FIGURE 7 is a large section on line 77 of FIG- URE 6.
FIGURE 8 is a partial side view showing the method by which the beads are rolled on the can.
DESCRIPTION OF THE PREFERRED EMBODIMENT The can body and lid of the present invention are shown in FIGURE 1. The can has a body generally designated 9 and a lid generally designated 11, the lid snapping over a bead or false wire 13 formed on the top of the can body 9. It will be observed that the Walls 15 of the can body are tapered and that an outwardly formed bead 17 is provided near the top of the can body and a second bead 19 is formed just below the top of the can body.
The lid 11 has an annular indentation 21 therein which corresponds in diameter roughly to the diameter of the bead 23. The method by which the cans stack is best shown in FIGURE 3 and it will be seen that the bottom bead 23 of one can fits snugly in the annular groove 21 of the next can below it so that the can stack in a very stable fashion.
In FIGURE 2, the nesting is shown and it will be seen that the outturned bead 17 of one can rests on the top head 13 of the can immediately below it so that the cans nest and occupy a minimal amount of room yet, because of the novel bead arrangement, do not wedge together so that the cans are easy to separate.
In FIGURE 4, there is shown the blank from which the novel can of the present invention is made. The blank comprises a sheet generally designated 25 of a suitable can-making material such as tin-plated steel of lb. weight. The body blank 25 has generally parallel but curved top and the bottom portions 27 and 29 respectively while the sides 31 and 33 are tapered at an angle to each other as is shown. Notches 35 are formed in the can body as is well known to those skilled in the art.
Referring now to FIGURE 5, the sequence of operations will be briefly described. The body blank 25 is inserted into the process at station 37. The blank is then moved to station 39 whereupon hooks 41 and 43 are formed on the ends of the blank. The blank is then moved to station 45 whereupon the two ends are wrapped together with the books 41 and 43 in engagement to form a tapered can body. The blank is then subjected to operation 47 where a hammer moves down, as shown by the arrow, bumping the seam and locking it. At this point, as is later brought out in detail, the formed seam is not parallel to the body of the can-making machine, but is at an angle thereto and in order to solder the seam in a subsequent operation, it is necessary to tilt the can in some fashion so that the seam is parallel to the path of movement. This is shown diagrammatically at station 48. At station 48, the smaller end of the can body is deformed into an oval so that the longer diameter of the oval as at 49 is the same as the diameter of the cylinder at the large end 51. Since dimensions 49 and 51 are the same, the seam is thus automatically brought into parallelism with the direction of movement through the can-making machinery so that when the can arrives at the station 53, the seam is parallel to the direction of motion.
The thus formed can body then passes to station 54 where the seam is treated with a flux to station 55 where the seam is heated and to station 57 where the seam is soldered. All of these operations are described in detail hereinafter. At station 59 a flange is formed on the bottoin of the can while at station 61 the beads 17 and 19 are formed on the can. At station 63 the bottom 65 is placed on the can body and at station 67 the bottom is rolled into place. The can is then inverted at station 69 and is now ready for shipment or filling.
FIGURES 6 and 7 illustrate the novel transport and tilting means for making the can of the present invention. The can is propelled along a production line generally designated 71 and in the early stages of the line, reciprocating fingers 73 are employed to push the can in a start, stop motion from one station to the next as is well known to those skilled in the art. At station 39 the hooks are formed at the edges of the can body as previously described. At the station generally designated 45, a mandrel 75 of generally tapered configuration having approximately the shape of the finished can is employed. The body 25 is placed under this mandrel, whereupon the body forming members 77 move upwardly around the hinge79, forming the body into a tapered configuration and causing the hooks 41 and 43 to engage. Then the operation designated 47 is conducted which comprises having the hammer 81 descend, bumping the seam and locking the same.
At this point, it is apparent that the newly-formed seam is at an angle to the general path of movement of the can body through the machine and in order to solder and finish the seam, it is necessary that the seam be brought parallel to the path of movement. To accomplish this, the tapered horn 83 is employed, the horn having an upper member 85 and a lower member 87 having curved surfaces thereon and being held in spaced relationship by rod 89. The maximum diameter of the horn 83 is essentially the same as the larger diameter of the can but the width of the horn is much less. Therefore, as the fingers 73 engage the end of the can body and push it over the horn 83, the smaller end of the can is distorted from its previous circular configuration to an oval configuration wherein the larger diameter 49 of the oval is substantially the same as the diameter 51 of the circle formed by the large end of the can. In this manner, the seam is brought into parallelism with the path of movement of the can through the machine. As the can passes over the horn 83, it comes into engagement with and is held by the magnetic guides or rails generally designated 91. The magnetic rails 91 are comprised of stainless steel tubes 93 having small bar magnets 95 therein, the magnets being substantially smaller than the inner diameter of the tubes so that water can be circulated through the tubes 91 to keep them cool, the direction of Water circulation being generally shown by arrows in FIGURE 6. Up to this point, the can bodies have been given a stopstart motion by means of the reciprocating fingers 73 but for the subsequent operations it is necessary that the can bodies move at a constant rate of speed through the machine 'for the soldering and associated operations rather than having the stop-start motion. Therefore, at this point, the can bodies are engaged by the fingers 97 carried at suitable intervals on the endless chain 99. Chain 99 is driven by means well known by those skilled in the art, not illustrated. At this point, the can body which has now had the seam hammered down and which is supported on the magnetic rails 91 and propelled by the fingers 97 passes under the flux station 54 where a flux is added to the seam thence to the heating station 55 where the seam is heated to the customary soldering temperature and then to the soldering station 57 where solder 101 is applied from roll 103. If necessary, the freshly soldered seam can be brushed for a neat appearance but this operation is not shown since it is conventional in the art.
At this point, the can body is essentially formed and at the next station, 59, a flange is formed on the bottom. Then the can body passes station 61 wherein the can body is supported on a mandrel 105 and brought into contact with roll 107 thereby forming the beads 17 and 19 as well as further forming the bottom flange 109, and flanging the top as at 111 preparatory to forming a bead thereon. Bottom is then put in place and then crimped. The bead 11 is then formed from the flange 111 at the station 67 and the can body is now complete.
It is believed apparent from the foregoing that a novel transfer means has been employed for making a tapered can.
1. The method of making a tapered can body comprising:
(a) forming a tapered body blank having curved,
parallel top and bottom edges and side edges tapering relative to each other;
(b) moving said body blank through a can forming machine;
(0) forming said tapered blank into the form of a truncated cone having a seam, said seam being at an angle to the path of travel;
(d) distorting the small end of the cone into an ellipse, said ellipse having a major axis equal to the axis of the large end of the cone, whereby (e) said seam is brought into parallelism with the path of movement of the can body through the machine.
2. The method of claim 1 wherein the small end of the cone is the leading end and a horn distorts the small end into an ellipse as the can body is moved over a horn.
3. The method of claim 2 wherein the can body is grasped by magnetic rails as the seam is brought into parallelism with the path of movement.
References Cited UNITED STATES PATENTS 1,966,380 7/1934 Dodge et al. 113-120 3,348,512 10/1967 Ericsson et al 1l3--120 CHARLES W. LANHAM, Primary Examiner.
RONALD D. GREFE, Assistant Examiner.