Patent GB-825734-A (GB)
Title: Apparatus for supporting web reels during unwinding
IPC: D01G15/42
Filed: 1957-11-21
Abstract: 825,734. Feeding webs. LANGSTON CO., S. M, Nov. 21, 1957 [Jan. 23, 1957], No. 36288/57.. Class 100(1) [Also in Groups XXIX and XXXIV] Apparatus for supporting web reels during unwinding comprises a rock shaft, a pair of arms on the rock shaft movable towards and away from each other, means on the arms for rotatably supporting a reel of web material, means adapted to rock the shaft, anchoring means, a fluid pressure cylinder and piston unit for each arm, each unit being secured at one end  to the anchoring means and at the other  end to the arm remote from the anchor-  ing means at the first-mentioned end, and  means to apply fluid pressure to the units  to move the reel supporting arms axially  on the shaft. As shown arms 4 and 5,  Fig. 1, are mounted on a shaft 3 carried  by end frames 1 and 2. The arms are slidably mounted on the shaft 3 by a key 6. The shaft 3 can be rocked by collars 9 and 10 keyed thereto and actuated by hydraulic cylinders 7 and 8 respectively. The arms 4 and 5 are movable axially of the shaft 3 by hydraulic cylinders 11 and 12 pivotally attached to the collars 10 and 9 respectively. Piston rods 11a and 12a are attached to the arms 4 and 5 respectively, such that the arms may be moved towards and away from one another along the shaft 3 or to the left or right under the control of valves in an hydraulic circuit. The arms 4 and 5 are brought together by depression of a button 60, Fig. 11, thereby energizing a solenoid 64, Figs. 7 and 8, which moves a valve 65 to the left allowing a pump 66 to supply hydraulic liquid to the piston rod ends of the cylinders 11, 12 through a valve 68, check valve 69, valve 65, check valve 70, and valves 71, 72. A control valve 75 controls the pressure exerted by the arms 4 and 5 on a web roll 21, Fig. 1, positioned between them. Liquid from the opposite ends of the cylinders 11, 12, Figs. 7 and 8, discharges through valves 78, 79 and 65 to a sump 77. The arms 4 and 5 are moved apart by equal amounts upon depression of a button 62, Fig. 1, thereby energizing a solenoid 84, Figs. 7 and 8, which actuates valve 65. Liquid is then supplied by the pump 66 through valves 65, 78 and 79 to the heads of the cylinders 11, 12. Liquid is discharged from the rod ends of the cylinders 11, 12 through a valve 85. The arms 4 and 5 may be moved axially of the shaft 3 by manual depression first of a switch 87, Fig. 11, and then a right or left push-button 88 or 89, thus energizing a solenoid 90 or 91 of valve 78 and a solenoid 92 of valve 93. When the button 88 is depressed solenoid 90 actuates the valve 78, such that liquid is supplied to the head of cylinder 12, thus moving arm 5 to the right. Liquid from the rod end of cylinder 12 flows to the rod end of cylinder 11 to move the arm 4 to the right, while liquid from the head of cylinder 11 flows to the sump 77 through valves 78, 79 and 65. Movement of the arms 4 and 5 to the left is caused by manual depression of the button 89. The lateral position of the arms 4, 5 is controlled automatically by a detector 100 having pneumatically-actuated switch units 102 103, 104 and 105, Fig. 6. Each unit comprises a casing having a diaphragm 106 with a central aperture 107 movement of the diaphragm operates one or more switches 109, 110, 111 or 112 which energize solenoids actuating valves in the supply to cylinders 11, 12. The casings of the units are connected by a pipe 108 to an air supply. Switches 109, 110 are normally open since the edge of moving web 113 covers apertures in a housing 101 above the units 102 and 103, while the switches 111, 112, Fig. 11, are normally closed since corresponding apertures are open. If the web deviates to the right so as to cover the, aperture, above the unit 104 the switch 111 is closed; further deviation causes closing of switch 112. If the web deviates to the left switch 110 is closed to energize solenoids 90 98, Figs. 7 and 8, which actuate valves 78, 99 respectively, thereby permitting liquid to be supplied to the head of cylinder 12. Arms 4 and 5 are consequently moved slowly to the right. The arms 4 and 5 are moved to the right at a higher speed when switch 109, Fig. 11, is closed thereby causing liquid to by-pass a valve 94, Figs. 7 and 8, in the same manner as that effected by manual closure of button 88. Similarly, the arms 4 and 5 are automatically moved to the left upon closure of 'switch 111 or switches 111 and 112, thereby energizing solenoids 91 and 114 and then solenoid 92. The tension of the web unwound is maintained substantially constant by a roller 45 around which the web passes. One end of the roller 45 is slidably mounted in horizontal slot 46 in a crosshead 34 and carries pistons slidable in cylinders 39 and 48 supplied with liquid under pressure. Movement of the roller 45 due to variation in web tension causes a cam 41 on a piston rod extension 40 to actuate a valve 38; thereby operating a pressure relief valve 115 to vary the pressure in the discharge pipes from hydraulic pumps 24 driven by rotation of the web roll. Each arm 4 and 5 carries a chuck 18 and 19 respectively provided with a spindle 20 for engagement with the central bore of a web roll 21. The arms 4 and 5 are raised and lowered by pistons slidable in the cylinders 7 and 8. For example, depression of a raise button 63 on arm 5, Fig. 1, causes energization of a solenoid 80, Fig. 8, thereby opening valve 68 to supply liquid to the top ends of cylinders 7 and 8, Fig. 7, until the roll 21, Fig. 1, has reached the desired height whereupon the button 63 is released. Similarly, a button 61 on arm 5 is depressed to energize a solenoid 130, Fig. 8, to actuate valve 68 into the position in which liquid may be returned from the top of cylinders 7 and 8 to the sump 77. A pressure switch 81 is held with contacts 82 closed and contacts 83 open until the weight of the roll is sufficiently diminished or the roll is returned to the ground, thereby preventing energization of solenoid 84 of valve 64 which causes movement apart of arms 4 and 5. A pressure switch 119 having contacts 120 in the circuit of the motor pulling the web is actuated to open these contacts should the rotation of an out of round roll 21, Fig. 1, cause sufficient fluctuation in pressure in the,line to cylinders 7 and 8. In a modification, two pairs of arms are provided for holding two rolls, the hydraulic connections for actuating these arms being controlled by a twoway valve for selectively, rendering either pair of arms operative. A photoelectric cell may be utilized for detecting lateral deviations of the web in place of the pneumatic detector 100.