Patent GB-723124-A (GB)
Title: Web supply mechanism for printing presses
IPC: B65H19/18
Filed: 1952-01-03
Abstract: 723,124. Feeding webs. GOSS PRINTING PRESS CO. Jan. 3, 1952 [July 31, 1951], No. 274/52. Class 100 (1). A web supply apparatus for printing presses comprises roll spiders for supporting running and replacement rolls, tension control means including a brake belt initially in braking engagement with the running roll and finally with the replacement roll upon transfer of web supply thereto to maintain running web tension, a paster assembly movable into an operative position adjacent the running web for joining the leading end of the replacement roll to the running web and severing the running web, and means for rotating the spider initially at a high speed when the web supply is transferred and at a relatively slow speed when the replacement roll engages the belt. As shown, Fig. 1, the web supply apparatus comprises a stand 10 including spiders 17 carrying rollsupporting spindles 18 on which paper rolls 11a, 11b and 11c are rotatably mounted. A shaft 19 carrying the spiders is rotatable by a two-speed electric motor 20 through reduction gearing 21, so as to rotate the spindles 18 into (a) a loading, (b) a reserve, and.(c) an operative position. The running web W is tensioned by applying belts 14 to the running roll 11b, the web tension being controlled by a floating roller 15 engaging a loop in the web W. The roller 15 actuates a hydraulic regulator 23 which controls the position of belt tensioning pulleys 25. A pre-drive mechanism 35 including belts 36, driven through differential gearing 40 from a printing-press (not shown), is movable into operating position to accelerate the reserve roll 11a to web speed by a pneumatic actuator 39 controlled by a solenoid 39A, Fig. 12. When the roll 11a, Figs. 1 and 2, reaches web speed the spider 17 is rotated, such that the roll 11a is adjacent the web W; simultaneously brushes 45 deflect the web W into engagement with the roll 11a previously prepared with adhesive. The brushes 45, Fig. 2, are supported by arms 51 and a shaft 50 on a carriage 46 pivotally supported on a shaft 47, the carriage being actuated towards and away from the web W by a pneumatic actuator 48 controlled by a solenoid-operated valve 64. The shaft 50 carries a lever 52 rocked by a pneumatic actuator 53, such that operation of the actuator 53 by energization of a solenoid 53A, Fig. 12, causes the brushes 45, Fig. 2, to effect a web splice, after which the expiring web is severed by a cutter 55 comprising serrated knives 56. The knives 56 are supported by arms 58 on a shaft 57 rocked through a lever 60 by a pneumatic actuator 59. A pipe 61 supplies compressed air to the running web W prior to splicing to prevent premature splicing and to remove the severed end of the expired roll immediately after severing. To maintain a constant tension of the web supplied to the printing press, arcuate feet 62 are provided adjacent the belts 14, such feet being arranged to deflect the belts into engagement with the new roll 11a. As the carriage 46 is actuated towards the roll 11a as the spiders 17 rotate, the new roll moves the feet 62 and so the carriage 46 to the right as seen in Fig. 2, the retraction of the carriage 46 being completed later by the actuator 48, the spiders 17 being rotated by the motor 20 at its lower speed. The web splicing operation is controlled electrically by means of relays 70-80 and 83-90, Figs. 12 and 13, switches 91-94, transformers 101-106, limit switches 111-114, and solenoids 39A, 39B, 48A, 48B, 53A, 53B, 59A, 59B, which actuate the corresponding actuators 39, 48, 53, and 59, Figs. 1 and 2. Closing of switch 91, Figs. 12 and 13, is effected manually when web renewal appears necessary. Thus relay 71 and so transformer 101 are energized, solenoids 39A and 48A being also energized as a result, so causing lowering of the pre-drive mechanism 35 and advancement of the carriage 46. The switch 92 is then closed to energize the relay 72, thus resulting in energization of relays 73 ... 76, when switch 112 is closed by a cam 18a, whereupon contacts 75b cause energization of the transformer 102 which in turn energizes the solenoid 53A to move the brushes inwards, while closing of contacts 75c result in energization of transformer 103 which energizes the solenoid 39B to cause retraction of the pre-drive mechanism, while contacts 75d complete a circuit including relay 83 which closes contacts 83a, 83b, and 83c of the motor 20. Contacts 76e complete a circuit to relay 79 which, through contacts 79a and 79b energizes relay 85 and de-energizes relay 86. The relay 85, through contacts 85a ... 85e, causes high speed operation of the motor 20. The limit switch 112 opens after passage of the cam 18a, thus deenergizing relay 73 and energizing relay 76, thereby closing contacts 76a and 76b, and conditioning relay 74 for energization when the switch 112 is again closed after one revolution. Contact 74b energizes the transformer 104 which energizes the solenoid 59A to actuate the cutter. The switch 113 is operated by the cutter to energize relay 78, transformer 105 which energizes solenoids 53B and 59B to retract the brushes and cutter, and to energize a solenoid 117b which applies a brake to the core of the expiring roll. Closed contacts 78d are opened by energization of relay 78 to deenergize transformers 102, 103, and 104. The limit switch 114 is then closed by the retracting carriage to energize relay 80 and de-energize relay 79 resulting in the de-energization of relay 85 and energization of relay 86, thus causing the motor 20 to be driven at low speed. Energization of relay 78 also results in energization of transformer 106 which causes energization of solenoid 48B to complete the retraction of the carriage. Limit switch 111 is eventually opened by disengagement with a cam 19a, Fig. 2, thus de-energizing the relays 71-80, Figs. 12 and 13, the de-energization of relay 77 causing de-energization of transformer 106.