Patent GB-887758-A (GB)
Title: A machine for printing flexible plastic containers
IPC: B41F17/18
Filed: 1960-04-11
Abstract: 887,758. Printing on curved surfaces. HAYWARD, H. M., and HUMPHREY, L. A. April 11, 1960 [April 13, 1959], No. 12721/60. Class 100(2) A machine for printing on filled flexible plastic containers 48 has a cylindrical carrier 12 which moves the containers past a rotating printing cylinder 7, the cylindrical carrier being mounted exchangeably on a spindle 11 which is adjustable in its relative position to the axis of the printing cylinder and the printing cylinder and the carrier having gear wheels 8, 15 attached thereto which are exchangeable to drive the carrier and the printing cylinder in predetermined peripheral relationship to each other according to the shape and size of the containers 48. The printing cylinder 7 is mounted on a shaft 6 journalled at one end in a frame 1 and driven by an electric motor (not shown) through gears 4, 5 and a pulley 2. The drive is transmitted to the carrier 12 through the gears 8, 15. The carrier 12 has a peripheral recess 13 across which locator bars 14 are fixed at intervals. The containers 48 are interconnected and are formed from plastic tube filled with the material to be packaged and divided into separate containers by fused seams. A strip of the containers is fed on to the carrier 12 from above, the containers resting in the recess 13 and the seams overlying the bars 14. A locator roller 21 having a radially extending fin 23a is rotatably carried by a bracket 11 adjustably secured to the frame 1 by means of a nut 20 and slot 19. The roller 21 carries a gear wheel 22 which meshes with the gear 15 of the carrier 12, the ratio of the gears being such that the fin 23 co-operates with the bars 14 to locate thereon the seams joining the containers. Two such locator rollers may be used at circumferentially spaced positions around the carrier 12. The printing cylinder 7 has an intaglio design and is inked by a roller 27 rotating in an ink trough 23 mounted for horizontal adjustment on a bracket 24, the bracket 24 being secured in a vertically adjustable manner by means of a nut 50 and slot 49 to the frame 1. The roller 27 is driven by means of a gear 28 secured thereto which meshes with the gear 8. The roller 27 does not touch the printing cylinder, the ink-transfer resulting from a build-up of ink thereon; the amount of ink transferred can be controlled by variation of the distance between the inking roller and the printing cylinder. A doctor blade 10 for the printing cylinder is adjustably mounted on a bracket 43 pivoted on an axially reciprocated shaft carried in the frame 1 and is biased into contact with the cylinder by a spring 45. Guide fingers 28a on the ink trough 23 direct the newly printed containers 48 away from the printing cylinder 7 on to a conveyer 29 driven through gears 34, 35, 15 from the carrier 12 at a speed slightly greater than that of the carrier. The conveyer is mounted in a frame 30 adjustably secured to the frame 1. The printing cylinder 7 and carrier 12 together with their associated gear wheels may be replaced by other cylinders or carriers so as to print a different design or accommodate differently shaped containers, the position of the spindle 11 being adjustable in a slot 16. Stopping arrangements. A bar 38 is pivoted adjacent to the nip between the locator roller 21 and the carrier 12. When the bar is lifted up by an obstruction on the carrier e.g. the operator's hand, it operates a micro-switch 39 which switches off the power supply and de-energizes a solenoid 42, Fig. 3. The solenoid 42 normally holds a brake shoe 41 on a lever 40 out of engagement with the driving means; when it is de-energized the brake is applied by a spring 52. Reference has been directed by the Comptroller to Specifidation 751,924.