GB1039106A - Improvements in or relating to web supply apparatus - Google Patents

Abstract

1,039,106. Feeding webs. R. A. BUTLER. May 22, 1963 [May 22, 1962], No. 20450/63. Heading B6B. [Also in Division F2] Web supply apparatus comprises a base 10, and a pair of collapsible mandrels 12, 14 (see Division F2), one for supporting a roll of running web and the other for supporting the replacement web roll. The leading end of the replacement web is prepared for splicing with a length of pressure-sensitive adhesive 102, Fig. 2. A pair of freely rotatable nip rollers 16, 18 are provided to form the splice. An accelerator is provided at each mandrel to set the replacement web roll in motion by a single side at the time that the splice is made to the running web. The accelerator comprises an arm 72 (88), a spring 76 (92) urging the arm in the web supply direction; a one-way clutch 70 (86) coupling the arm to the mandrel, and a latch 74 (90) engaging the arm and releasable to cause the force of the spring to be applied through the arm and the clutch for accelerating the replacement web roll. A detector for each web-roll which sets the splicing operation in motion when the diameter of the running webroll is near exhaustion comprises a lever 240 (256), Fig. 1, which operates a normally open switch 252 (268) with a flexible finger 248 (262). The switch energises a solenoid 20 (22). A thumb-screw 250 (266) which is engaged by the flexible finger, prevents the lever from resting heavily on the surface of the running web-roll, the first few layers of which nearest the core may be distorted. The switch is operated when the finger 248 escapes from the screw, due to the weight of the lever when finally not supported by the running web roll. In operation, when the solenoid 20 is energized, the latch 90 which is connected to the armature 170 of the solenoid by a cable 270 is released. The mandrel 14 is therefore given a kick start to accelerate the replacement web roll. Movement of the armature 170 also causes a lever 144, Fig. 2, through a cable 174 and a spring 178 to raise the leading end of the pressure-sensitive tape 102 into the nip between rollers 16 and 18. The leading end of the replacement web was previously attached by suction to a member 134 fixed to a vertical slide 136 which co-operates with two levers 144 and 146. At the same time the armature 170 causes a blade 182 to pivot into engagement with the underside of the exhausting running web 26 to press it against a stationary blade 190 thus severing it. When the web roll 28 on mandrel 14 is near exhaustion, the armature 22 releases the latch 74 and operates the lever 142 and the pivoted cutter blade 184 in the same manner. Spring-pressed rollers 216 and 220 mounted on a movable block 228 guided on parallel rods 232 take up any sudden changes of tension in the running web. The web is also guided laterally before passing between rollers 16 and 18 by a pair of fingers 196 (208) depending either side of the web from the fixed knife blade 190 (202).