Patent GB-453046-A (GB)
Title: Improvements in or relating to web supply mechanism for printing and other machines
IPC: B65H19/18
Filed: 1934-12-03
Abstract: 453,046. Feeding webs. HOE & CO., Ltd., R., 109, Borough Road, London.- (Lundquist, A.; 260, West End Avenue, and Freeman, R. A., and Wieking, W. C. ; c/o Hoe & Co., Inc., R., 138th Street, both in New York, U.S.A.) Dec. 3, 1934, No. 34750. [Class 100 (i)] A web-supply apparatus for printing or other machines comprises a support for running and reserve rolls, a driven belt normally engaging the running roll for tensioning the web, manually operable means for initiating movement of the support to bring the reserve roll into contact with the belt to be speeded up thereby and to bring its periphery adjacent to the running web, a first device for moving the running web into contact with the reserve roll, a second device for severing the running web, a locking mechanism holding these devices against operation, and a control mechanism comprising two elements which, when operated together, release the locking mechanism, one of the elements being operated at each rotation of the reserve roll, and the other element being manually operated. The running roll 32<a>, replacement roll 32b, and a reserve roll are mounted on a three-armed frame 33 secured to a shaft 28 rotatable by an electric motor to bring the rolls successively into the normal running position which is that occupied. by the roll 32b. In this position the running roll is braked by one or more endless belts 34 passing over pulleys 35, fixed to a shaft 38, pulleys 36 loose on a shaft 43, and pulleys 37 carried by arms 45 fixed to the shaft 43. The pulleys 37 are mounted in arms 48 pivoted in the ends of the arms 45 and pulled by a spring 52 to hold the belts 34 in tension. The' belts are driven from the shaft 38 at a speed slightly less than web speed, and the extent of their wrap round the roll is varied automatically upon variation in tension of the web to restore the tension to normal. For this purpose, the shaft 43 is provided with a toothed quadrant 58 engaged by a pinion 57 adapted to be driven through reduction gearing from a reversible electric motor 54 controlled by the movements of a roller 59 resting in a loop of the web W. This roller 59 is carried by arms 61 fixed to a shaft 63 to which is also secured an arm 65 carrying an adjustable weight 66 by which the normal web tension may be varied. A cam shoe 69 formed on the arm 65 is adapted, upon the rising or falling of the roller 59 to operate one or the other of a pair of switches 71, 72 to drive the motor 54 in the appropriate direction to restore the tension. A limit switch 159 in the motor circuit, actuated by a lug 163 on the shaft 43 limits the upward movement of the arms 45. The means for pressing the expiring web against the replacement roll comprises brushes 89 carried by a frame 82 fixed to a shaft 84 and the knife for severing the old web after the join is effected is carried by a second frame 83 fixed to a sleeve freely mounted on the shaft 84. These frames 82, 83 are normally held together, so as to move in unison by a latch adapted to be released by an electromagnet, and are also normally held in a substantially horizontal position. Just prior to the renewing operation they are moved manually into the position shown so that when the electromagnet is excited to release the latch, the frame 82 is pulled inwardly by a spring 102 to press the web against the roll to effect the join. The circuit of the electromagnet is closed by a push-button switch 129 and a timing switch 128 closed by a cam 126 on a device 132 holding the free end of the web of the roll 32b. The inward movement of the frame 82 brings an arm 153, pivoted thereto, into the path of a projection 158 on the webholding device 132 to be struck thereby and thus release the knife for severing the old web. The cutter blade 93, Figs. 9 and 13, is slidably mounted in a housing formed by plates 130, 131 at the lower end of the frame 83 and is normally retained with its cutting edge within the housing by a stud 144 engaging a hole in the blade and carried by an arm 142 fixed to a rock-shaft 143 mounted in the frame 83 and connected by an arm 149 and link to the arm 153. The blade is provided with inclined slots 133 spanning studs 132 carried by the housing plates 130, 131 and a tension spring 134 is attached to one end of the blade and to the housing. When the arm 153 is struck by the projection 158, the shaft 143 is turned against the action of a spring thereon to withdraw the stud 144 from the blade to allow the blade to be pulled longitudinally by the spring 134 so that its edge is projected beyond the housing to sever the web. The blade is reset by a handle 139. During the web-renewing operation, the control for the belts 34 by the roller 54 is rendered inoperative by the provision of a lug on the shaft 84 adapted, when the frames 82, 83 are lowered, to open a switch in the circuits of the motor 54. The shaft of the motor 54 is provided with an electromagnetically operated brake which normally holds the belt arms 45 after adjustment, but when the motor for moving the rollsupporting frame 33 is operating and when the frames 82, 83 are in their lowered position the circuit of this brake is energized to release the brake and thus free the arms 45 from restraint. In a modification, the shaft 43 is provided with an arm carrying a roller round which the web passes the roller taking up or paying out web as the arms 45 are adjusted. Specification 453,112 is referred to.