Patent GB-551492-A (GB)
Title: Improvements in or relating to the manufacture of coated cans or containers or like articles
IPC: B05C9/04
Filed: 1941-05-12
Abstract: 551,492. Endless conveyers. CROWN CORK & SEAL CO., Inc. May 12, 1941, No. 6145. Convention date, July 25, 1940. [Class 78 (i)] Plant for the manufacture of cans and like articles comprises an oven for heat-treating the cans, a plurality of endless conveyers arranged side by side and having horizontally-disposed upper and lower flights in the oven both used for conveying adjacent flights of the separate conveyers being driven in opposite directions, and devices for transferring cans from one convever at the end of a flight to the adjacent conveyer for movement therewith in the opposite direction whereby the cans traverse all the conveyers in one flight successively and follow a serpentine path through the oven at one elevation. In the arrangement shown diagrammatically in Figs. 4 and 5 and comprising two ovens 10, 11 having lower conveyer flights 29a ... 29g, 29a<SP>1</SP> ... 29g<SP>1</SP>, and upper flights 28a ... 28g, 28a<SP>1</SP> ... 28g<SP>1</SP>, respectively, the cans are conveyed from an inside-spraying machine 70 by a conveyer 60 and a transfer device 62 to the lower flight 29a of the first conveyer of oven 10. At the other end of the oven a device 50 transfers the cans to the lower flight 29b of the second conveyer which moves the cans back to the other end of the oven again. Similarly, transfer devices 40, 51, 41, 52, 42 transfer the cans in succession to the flights 29c ... 29g, and finally a device 63 transfers the cans to a cooling conveyer 61, in which blasts of air may be used, after which another device 64 transfers them to a conveyer 72 for other operations. The cans then pass in succession through a bottom-seaming machine 73, a pressure-tester 74, and two out-side coating machines 75, 76 to a device 77 which delivers them to the upper flight 28a of the first conveyer in the oven 10. By means of other transfer devices 45-47, 55-57 and 65 the cans are passed through the upper flights in the oven and are transferred to the upper run of the cooling conveyer 61. From the oven 10 the cans are transferred by a device 66 and a conveyer 78, 79 to a printing machine 80 after which they pass along the lower flights 29a<SP>1</SP> ... 29g<SP>1</SP> of the oven 11 to a cooling conveyer 61<SP>1</SP> and a conveyer 78<SP>1</SP> leading to an outsidevarnish spraying machine 86. From this machine they pass in the same way along the upper flights 28a<SP>1</SP> ... 28g<SP>1</SP> of the conveyers in the oven 11 and are finally delivered by a transfer device 66<SP>1</SP> and a conveyer 90. The oven 10 is maintained at a high temperature, say, 430‹ F., and the oven 11 at a lower temperature, say, 250‹ F. Each of the oven conveyers comprises a pair of endless cables, the cables forming the upper and lower flights 28a, 29a of the first conveyer, being shown in Fig. 2; these cables pass over guide sheaves 13, 14 and a tensioning sheave 15 at one end and over a guide sheave 30 and a driving sheave 17 at the other end. The second conveyer passes over a driving sheave 16 instead of the sheave 17, these two sheaves being driven from a motor 35 in opposite directions so that the first and second conveyers are also driven in opposite directions. The third conveyer passes over the sheave 17 and the fourth over sheave 16 and so on. The cables are supported at intervals by rollers 100, 101, Figs. 6 and 8, mounted on spindles carried by rails 104, 105, which are made in lengths secured together by cross-pieces 113 and bolted at 115, 116 to the oven frame, the slotted connection at 116 allowing for expansion. The rails 104, 105 are flared outwardly at 120, 121, and perforated sheet-metal guard plates 122 are secured thereto. Doors 95, 96 are provided for access to the interior of the oven. Specifications 549,304 and 552,014, [both in Group III], are referred to. Transfer devices.-The cans are transferred from the outside conveyers, such as 60, Figs. 17 and 18, to the first flight 29a within the oven by means of an endless chain 235 passing round sprockets 229, 230 and driven by a motor 240 at a speed corresponding to the speed of the conveyers 60, 29a. The sprockets and the chain are inclined as shown so that the sprocket 230 is below the conveyers and 229 is above them. Thus the chain passes up between the cables 60, lifts the cans from these cables, carries them across the sprocket 229 - and passes down between the cables 29a to deposit the cans thereon. Guide plates 202, 203, which may be lined with synthetic resin, extend around the sprockets 229 and are fixed to the framework 200, 201. This framework comprises the bars 200, 201 and longitudinal rods 205, 206 supported at an adjustable height on floor pedestals 215. Similar devices are provided for transferring cans from one flight to the next in the ovens, these devices being driven by a common motor or motors 167, Fig. 2. Turning articles during transit.-The cans may be turned from a horizontal to a vertical position by a transfer device at 71, 77 or 81, Fig. 4. This device comprises an endless chain 250, Figs. 19 and 20, passing round sprockets 251, 252 driven in any suitable manner. Brackets 255 are pivoted at 256 to plates 257 on the chain and comprise parts 258, 259 to engage respectively the neck and body of a can. As the cans move to the left in Fig. 19 a cam rail 261 gradually turns the brackets through 90 degrees and another rail 262 supports the bases of the cans until they rest on the conveyer cables 60<SP>1</SP>.