Patent GB-826647-A (GB)
Title: Web splicing apparatus
IPC: B65H19/00
Filed: 1956-04-10
Abstract: 826,647. Feeding webs. MIEHLE-GOSSDEXTER Inc. April 10, 1956 [April 21, 1955], No. 10910/56. Class 100(1) [Also in Groups XXIX and XXXV] Apparatus for splicing a running web drawn from an expiring roll to a new web roll wherein the rolls are movably supported, comprises means for driving the new roll so that its peripheral speed will substantially match that of the running web before the splice is made, retarding means operative on the expiring roll to create an adjustable predetermined tension in the running web, a paster carriage including a brush for deflecting the runing web against the roll and a knife for severing the expiring roll web, means whereby the new roll will be moved into operative engagement with the retarding means after such severing, a brake operating on the new roll as it moves towards the retarding means, and a generator for producing a signal proportional to the predetermined tension whereby the brake is controlled to maintain a corresponding tension in the new roll web during transition. General description. The rolls are mounted on the arms 90-92, Fig. 2, of spiders 88, 89, Fig. 3, which are axially spaced on a reel shaft 21 between frame members 51, Fig. 1, and driven for posi-  tioning of a new roll by a motor 22. Tension in the running web W is maintained  constant by the drag of the feeding roll 25 by straps 30 the drag being adjusted by plunger 45 in accordance with the effect of a loop around a pulley 36 on a compressed air control system comprising a reservoir 41, a manually adjustable pressure regulating valve 42 and a control valve 44. The rolls may be rotated under manual control, but splicing which includes running the new roll up to speed before connection, pasting and severing, and maintaining the tension during the transition period, is fully automatic after the "position" button is operated and held down for a predetermined period. The new roll is run-up by a continuous belt 58 on a retractable carriage assembly 16 which is lowered at the appropriate time the belt 58 being driven by a motor 59 in response to the difference between the web speed indicated by a tachometer 170 and the speed of the new roll indicated by tachometer 154. The carriage is moved hydraulically by a piston in a cylinder 54 under the control of a solenoid operated valve 55, and the tension of the new web during the transition period is held constant and equal to the normal tension by regenerative braking in the motor 59 under the control of a potentiometer 205a, the wiper of which is operated by a bellows from the pressure supply pipe to the web tension loading cylinder 40. The potentiometer wiper 205a may alternatively be ganged to the control knob of valve 42. The brush 78 and knife 79 both of which are solenoid operated are mounted on a retractable paster carriage 17 which is pivoted between the frames 51, and normally latched in its retracted position, the carriage being driven between its two positions by a piston in an hydraulic cylinder 69 under the control of solenoid operated valves 70, 72, 73 and a bleeder 401 when the latch is hydraulically released. Safety arrangements are provided for preventing injury to a person or the machine if an operator or a foreign body becomes trapped by the retracting carriage. Electromagnetic brakes 95, operative on the spindles 94 to which the rolls are chucked, are energized by cam switch KLS on the knife shaft when the web from the expiring roll is severed. Automatic switching is effected by mercury switches on the carriages, cam operated and mercury switches on the spider, and a photo-electric arrangement 135 mounted on the frames in a position to locate the new roll for pasting. Electrical control. The motor 22 which is. controlled by a contactor R1, Fig. 19, may be manually controlled by push-button M, Fig. 18. To initiate splicing the "position" button is held down and the energization of relays R and POS which results causes the motor 22 to drive until the new roll interrupts the light beam :in the photo-cell 135 to de-energize relay PE and thus release contactor R. Solenoid 71 controlling the paster carriage valve 70 is energized and the carriage is lowered under the influence of the bleed through valve 401 until limit switch ICLS-I is actuated to halt the lowering and energize solenoid 74, 75 whereby valves 72, 73 are opened to drive the carriage to its operative position and to energize solenoid 56 of the pre-drive carriage control valve 55 Limit switch 2CLS on the paster locks relay POS renders inoperative pushbutton M and prepares a circuit including a "pre-drive" switch-to relays PD, PDX, PDS. Release of the "position" button  anywhere before the time of operation of  the paster limit switch 2CLS results in retraction of both carriages. The press is brought to a reduced speed tor the splicing by means of relay POS and circuits, Figs. 20, 21 (not shown). When the pre-drive switch is operated brake 95 is released on the new roll, a path from wiper 205a, Fig. 8, to the grid of valve 252 is completed and .the speed control circuit of motor 59 including tachometers 170 154 and amplidyne 60 becomes effective to run up the new roll. The control grid of valve 182 receives a high positive potential from tachometer 170 and owing to the .resulting decrease in potential of line 208 and increase in line 209 the current through amplidyne winding 60c in the anode of valve 214 is reduced to a minimum, resulting in conjunction with winding 60D in the anode of valve 215 in maximum amplidyne output and in consequence in maximum motor acceleration. Resistors 234, 235, reduce the effects of induction, and valve 244 the anode of which is connected to line 209 provides a limiting effect. When the current through amplidyne compensating winding 60b exceeds an amount predetermined by potentiometer 202a the limitation is effective through resistors 196 and 218 to reduce the bias on the grid 213' of valve 215. Splice warning lights PF, PY, are lit by relay PD. When the motor cur- .rent is steady depression of the pasting switch energizes a .self-locking relay PA which in conjunction with contacts 98 operated by the rotation of the roll on its spindle, operates relays E and D in tandem the latter. being self-holding and effecting.the following operation: (1) locks the positioning coil; (2) opens the path from potentiometer wiper 205 to grid 252 through contact 73; (3) opens constant speed circuit, Fig. 20; not shown; (4) opens preset press speed circuit, Fig. 21, not shown, to enable a reduction in speed to be made and (5) prevents operation of stop circuit if "red stop" button pushed (at this stage splicing may be completed - whilst machinery is coasting). When relay E is released. by contacts 9.8 when the roll rotates to its pasting position solenoid 329 is operated to release the brushes and make the joint. The knife solenoid is operated on the next closure of contacts 98 and switch KLS on the knife shaft applies brake 95 on the expiring reel. Limit switch contacts BL51. BL52 close and continued rotation of the roll re-operates relay E which now locks up and operates relays PDSX and PDS to apply regenerative braking through motor 59 during the transition period and initiate carriage retraction. For regenerative braking valve 184 is cut off and 188 conducts heavily 'to create a current though amplidyne winding 60c which is controlled by a valve 250 in accordance with the setting of potentiometer wiper 205a Reel limit switch RLS-1 actuates on contact of the new reel with the tensioning belts and releases relay PDX to disconnect grid 252 from potentiometer 270 or 205. Condenser 271 then discharges slowly to cause 'the gradual decay of the regenerative braking. Release of relay PDX enables the press speed to be increased if so desired and as the reel continues to rotate reel limit switch RLS-2 opens and releases relay PD to retract the pre-drive carriage. Switch RLS-3 opens on further reel rotation and at this point the reel is halted if the carriage', is not fully retracted. Finally switch RLS-4 opens when the reel is in its normal feed position and relay "POS" is released and all solenoids and relays are de-energized. Mechanical features. An index is provided on the reel spindle to indicate the pasted area of the new roll. The brush and knife shafts 306, 308, Figs. 11 and 12 are non-circular and have an integral lip 306a to which a number of brushes 78 belt denectors 314 and knives 79 can be bolted. The shafts, are biased by springs 316, 318, 319, 320, and are latched in the withdrawn position by mechanical linkage during car- - riage retraction. : The belt deflectors 314 and a hollow web deflector tube 345 which is' recessed to fit around the tension belts help to prevent longitudinal wrinkle, the latter has a contacting surface with a large radius of curvature of the order of two hundred times the web thickness. The brush pressure may be adjusted by wheel 374 and detent 376. Provision is made for adjustment of the brush pressure so that it may be reduced when narrower rolls are fed into the press and for the knives to be brought to a smooth stop, when released, by hydraulic shock absorbers 360. The presence of a foreign object in the paster carriage retraction path, detected ,by a deflector plate 340 actuates a switch CSS and drops out relay POS, whereby solenoids 74, 75 are de-energized, and valves 72, 73 closed to trap the fluid in cylinder 69 and halt retraction. Specifications 743,351, 826,648, 826,649, 826,650 and 826,651 are referred to.