Patent GB-248091-A (GB)
Title: Improvements relating to intermittent driving-mechanism for feeding continuous stripmaterial
IPC: B65H23/18
Filed: 1924-12-01
Abstract: 248,091. Forgrove Machinery Co., Ltd., and Grover, F. Dec. 1, 1924. Feeding and registering webs. - In apparatus for feeding strip material, such as a strip of wrapping material, intermittently in register with impressions on the strip, the feed device is adapted to feed a length of material greater or less than the distance between two impressions, the length to be fed at each feeding operation being selected automatically by the lowering of an electric contact brush or brushes on to the stationary strip the brushes coacting with conducting ink on the strip or with a metal part exposed by perforations in the strip. Each brush is in circuit with an electromagnet which controls the position of a member adapted to assume two positions with respect to a moving part of the feed device and thus determine whether a long or short feed shall be given to the strip on the next feeding operation. In one form, Fig. 1, the strip G of wrapping material perforated at intervals passes from a reel H round guide rollers H<1>, H<2>, over a metal contact stud J, and a guide roller H<3> and between the feed rollers D to a severing knife F. The feed rollers are driven by gearing from a gear A operated by a friction ratchet gear comprising a pawl C having a notch C<1> engaging an annular flange A<2> on the gear A., the pawl being operated by a boss C<2> oscillated by a link C<3> and crank C<4> on the driving shaft C<5>. Co-operating with the stud J are two contacts brushes K<3>, K<4> on pivoted arms K, K<1> which are raised and lowered by arms K<5> on a shaft K<7> rocked by connections K<8>, K<9> from an arm R<10> operated by a cam K<12> on the shaft C<5>. The opposite sides of the gear A are frictionally engaged by arms L<1>, L<2>, Figs. 1 and 4, pivoted on a bracket L and one arm L<1> has pivoted thereto a double-armed lever, one end M of which lies between two electromagnets N, N' in circuit with the brushes K<3>, K<4> respectively, and the other arm of which is in the path of a member O mounted on the boss C<2> and having two notches O<1>, O<2> of different depths. At the end of each idle stroke of the pawl C, one of these notches engages the end M<1> of the lever, thereby swinging the arm L<2> to rotate the gear A so as to give a slight backward feed to the strip. According to whether the notch O<2> or the notch O<1> engages the lever, the backward feed is greater or less and the next forward feed is thus a short one or a long one. In the operation of the machine, if the strip is in advance of its correct position the brush K<3> makes contact through a perforation in the strip and closes a circuit to excite the electromagnet N, which thereupon attracts the arm M to bring the end M<1> into the path of the notch O<2>. If the strip is behind its correct position, the brush K<4> makes contact through a perforation in the strip and closes a circuit to the electromagnet N<1> whereby the arm N<1> is brought into the path of the notch O<1>. In the form shown in Fig. 5, a single brush K<3> is provided, adapted, upon passing through a perforation in the strip, to close a circuit to energize an electromagnet N which thereupon attracts one end P of a lever. A stop Q on the other end of the lever is thereby moved into the path of the pawl C and arrests it before it has completed its normal idle movement. The next operative movement of the pawl is thus shortened and the shorter length of strip is fed. Specifications 177,321 and 220,805 are referred to.