| 摘要 |
417,500. Feeding webs. HOE & CO., Ltd., R., 109, Borough Road, London.-(Assignees of Tomlin, J. R., Lundquist, A., and Horton, A. J. ; 138th Street, New York, U.S.A.) Jan. 2, 1933, No. 24132/34. Convention date, March 3, 1932. Divided out of 417,443. [Class 100 (i).] A web-renewing mechanism for printing-presses and other machines comprises a support carrying a running roll and a reserve roll and adjustable to suit rolls of different widths, an electrically operated web deflector for pressing the expiring web against the reserve roll, a timing device rotatable with the reserve roll, conductors completing the circuit through the timing device and the means for operating the deflector, and mechanism for taking-up or paying-out the conductors when the support is adjusted. The mechanism described is identical with that described in Specification 417,443. The running and reserve rolls 28, 29, Fig. 1, are mounted between a pair of arms 11 adjustable in accordance with the width of the rolls upon spaced shafts 8, 81 carried by members 7 having spindles 6 mounted in pedestals 5. One of the spindles 6 carries a gear wheel 16 adapted to be driven by an electric motor 22 to rotate the support to bring the rolls from loading position to the normal running position which is that occupied by the roll 29. The roll surfaces are engaged by fingers 23 secured to shafts 25 rotatable in the members 7. When a running roll in normal running position is reduced to a certain diameter, its finger 23 closes a switch to start the motor 22 to bring the reserve roll into running position. The fingers 23 are adjustable along their shafts to suit rolls of different widths. The running web is pressed against the reserve roll upon the de-energization of a magnet 48 which occurs upon the closing of a circuit which includes a timing device on the spindle of the roll and contact segments carried by one of the spindles 6. The timing device comprises a contact segment rotating with the roll spindle and adapted during its rotation to bridge a pair of brushes mounted on the roll-supporting arm 11. The brushes are connected to the contact segments carried by the spindle 6 by flexible conductors, and, to prevent slack in these conductors when the arm 11 is adjusted, the take-up mechanism shown in Fig. 25 is provided on the arm 11. The conductors from the brushes, and from a similar pair of brushes of the timing device at the other end of the arm 11, are taken to a junction box 184 from which a four-conductor cable 185 is led round lower and upper sheaves 187, 186 and thence round a guide pulley 188 to an anchorage on the adjacent member 7. The cable is also anchored near the junction box 184 by means of a clamp 189. The sheaves 186 are mounted on a fixed stud 191 and the sheaves 187 on a stud 192 carried by a head 193 slidable on guide rods 194. Springs 197 on the rods urge the head 193 in a direction away from the sheaves 186. Specification 417,499 also is referred to. |
