Patent GB-369463-A (GB)
Title: Improvements in method and apparatus for registering printed webs of paper
IPC: B65H23/188
Filed: 1931-05-15
Abstract: 369,463. Feeding webs. PACKAGE MACHINERY CO., 132, Birnie Avenue, Springfield, Massachusetts, U.S.A. May 15, 1931, No. 14450. Convention date, May 15, 1930. [Class 100 (i).] Mechanism for controlling the register of an indicia-bearing web relative to a web-treating device comprises a web-feeding device together with mechanism responsive to deviations in register for varying the amount of web delivered, and mechanism for stopping the feed when the deviations exceed a predetermined amount. The mechanism as described comprises a photo-electric cell acting, in conjunction with a lamp and the indicia on the web, to break the circuit of an electromagnet 57, Fig. 11, controlling a differential gear. Whenever a part of the web which is more or less transparent than the rest of the web comes between the cell and lamp, the change in current energizes a solenoid 23 which attracts a pivoted armature 24, thus breaking the contacts 25, 26. This break is, however, nullified if the web is in register by a contactpiece 29 carried by a commutator 28 rotating in timed relation to the cutting mechanism. which engages a fixed contact 30 to complete the circuit of the magnet 57 through the lead 72. The web is normally fed at a speed greater than necessary, so that any stretching of the web within limits will be automatically corrected ; when, however, the cutting line of the web arrives ahead of the cutting operation, due to contraction of the web or other causes, the solenoid 23 will be energized before the member 29 engages the contact 30, and the circuit of the coil 57 is broken to slow down the feed as described below. In addition should the lack of register be in excess of a predetermined maximum the feed is stopped by breaking the circuit of the main driving motor through the circuit breaker 77. For this purpose, the commutator 28 carries an additional contact member 31 adapted intermittently to engage a strip 32 connected as shown to a contact 27 and through the current source 80 to the armature 25. The energizing coil 81 of the circuit breaker 77 is therefore always energized except when the armature 25 is attracted by the coil 23 and the member 31 does not engage the contact-piece 32, and this occurs when a transparent part of the web passes between the cell and the lamp and the web is so far out of register that the commutator 28 is not in contact with the member 32. The gearing employed comprises a driven shaft 35 carrying the feed roll 18 : the shaft 35 carries a loose driving gear 36 and a gear 37 fixed upon it. The gear 37 has a hub 38 on which is mounted a freely rotatable planet-carrying member 40. A planet shaft 44 carries two pinions 45, 46, meshing with the gear 37 and with a gear 47 fixed to the hub of the gear 36. The gears 37, 47 and also their respective pinions 45, 46 are arranged to differ preferably by one tooth. The shaft 44 is normally locked against rotation in the member 40 so that the gearing rotates solid inside a gently applied slipping brake 65. When the shaft 44 is free, this release being effected as described below when the magnet 57 is de-energized, the brake 65 comes into action to hold the member 40, and the gear 37 is driven through the train at a reduced speed. To lock the shaft 44 in the member 40, it is provided with a cross-piece 50, Fig. 2, normally engaged by a stop 53, carried by a pivoted arm 51, to which is attached by a rod 61 a pivoted armature 58 of the electromagnet 57. In the normal running of the machine,. the stop 53 engages the cross-piece 50 to lock the shaft 44 against rotation to effect solid driving. When the electromagnet 57 is deenergized as described above, the arm 51 is released and moves to the right of Fig. 3, under the action of a spring to free the shaft 44, which can then rotate until relocked by the stop 53 and bring in the speed reduction. Re-energizing the magnet 57 is insufficient to draw back the armature 58 for this purpose and this is done mechanically by a second crosspiece 64, also carried by the shaft 44 as shown in Fig. 2, which returns the stop 53 to the position shown in Fig. 3.