| 摘要 |
869,914. Cutting and punching apparatus. MINNESOTA MINING & MANUFACTURING CO. Feb. 14, 1958 [March 28, 1957; March 29, 1957], No. 20266/60. Divided out of 869,913. Classes 31 (1) and 31 (2). [Also in Group XV] A rectangular portion is cut out of a series of cards 5, Fig. 1, by a die mechanism 17, Figs. 1, 27 and 28, being one of a plurality of mechanisms constituting a machine for performing various operations on the cards (see also Specification 869,913, Group XV). Each card is fed in turn by a conveyer (see Specification 869,913, Group XVI) to a position above a tube 403 and below a tube 429, which during each machine cycle are moved towards and away from each other by cams on a shaft 388 through levers 393, 402. Secured to the top of the tube 403 is a die holder 415 having a central rectangular opening 417 and carrying two pairs 418, 423 of opposing knives forming a rectangle. When the tube 403 is raised, the knives move upwardly through an aperture in a card supporting plate 172 and cut out a portion of the card in co-operation with an upper cutting block 428 carried by the tube 429, between which and the block is secured a rubber cushioning pad 438. The cut-out portion is contacted by a perforated plate 462 of a rectangular vacuum shoe 459 formed at the lower end of an annular member 464 which slidably fits in a flanged bushing 465 secured in the tube 429, and is secured to a tube 466 received in a cap 473. Vacuum is supplied by a pump 502, driven by an electric motor, through a valve 508 and vertical passages 467 to the shoe. The tube 429 is reciprocated vertically by a cam through the lever 481, and by a compression spring 490. The plate 462 moves with the cut-out into the opening 417, and at the bottom of the stroke of the tube 429, ports 469, 468 in the tube 466 and the member 464 become aligned with ports 470, 471 in the bushing 465 and the tube 429, so as to release the vacuum and allow the cutout to fall on to an annular choke plate 495. The cut-outs thus collect in the form of a pad 496 until the pad is of sufficient thickness for its top to be engaged by the shoe 459, whereafter it is gradually forced through the choke, plate 495, small sections breaking away from the bottom of the pad and falling into a receptacle. Vacuum in the shoe 459 is also cyclically controlled by a cam on the shaft 384 actuating the valve 508. The vacuum pipe from the valve 508 to the shoe passes through a T-fitting, one branch of which leads to a chamber from which a portion 536, Fig. 33, of a plunger protrudes, being retracted against the force of a spring when there is vacuum in the chamber. During each cycle, an arm 545 having a cam surface 544 and mounted on the bell-crank 481 moves downwardly, and if no cut-out is held on the shoe, so that there is no vacuum, the plunger is not retracted and engages the surface 544 to swing the arm 545 about its pivot stud 547 to engage the plunger 552 of a switch 553, which is thereby closed to stop the machine. The cards 5 so treated are thereafter moved to the right in Fig. 1 to a position 5b, Fig. 39, where they are each to receive against an adhesive portion surrounding the cut-out a film frame or section which for this purpose is cut from a film supplied from a roll 578 (see Specification 869,913, Group XVI) to cutting position, Fig. 39, the speed of the feed rollers being regulated so as to stop the film in the exact position required for cutting by a photo-clutch cell sensing the division line between two adjacent sections of film (see Specification 869,913, Group XVI). The cutting mechanism 20 is operated by cams on a shaft 807. The film is located below a holder 829 carrying spaced knives 832 which cooperate with stationary blades 835. The holder 829 is lowered for cutting against the action of a spring 830, by a cam 810. One pair of blades cuts off the end film frame, while the other pair trims the leading edge. The cut-off frame is deposited on a rectangular vacuum head 838 (see Specification 869,913, Group XV). While the head 838 is lowered to remove the frame to the left, the gap between the blades 835 is bridged by a plate 949 which is automatically caused to follow the head 838 by means of a spring 952, being forced back when the head returns. If there is no cut-off frame held on the head 838, no suction will be built up therein, and a plunger 909 will remain projecting therefrom, and will engage a lip 912 to close a switch and stop the machine. |
