Patent GB-155055-A (GB)
Title: Improvements relating to sheet feeding mechanism of printing and like machines
IPC: B65H3/20
Filed: 1919-09-23
Abstract: 155,055. Salmon, H. J. Sept. 23, 1919. Feeding sheets; pile supports; sheet-forwarders; sheet-separators.-Sheet-feeding mechanism comprises a skeleton drum consisting of a series of disks mounted on a spindle and rolled backwards and forwards over the top of a pile of sheets, adhesive wheels or pads carried upon supports mounted to revolve with the drum, and means for projecting the adhesive wheels &c. into contact with the rear edge of the top sheet when the drum reaches the limit of its backward movement, so that, when the drum commences its forward movement, the rear edge of the top sheet is lifted by the adhesive wheels &c. and seized by grippers on the disks. The skeleton drum or series of disks c is mounted on a spindle d, and rolled backwards and forwards over the pile of sheets supported on a table b by means of rocking arms v oscillated by means of a crank pin x on a rotating disk y engaging slots w in the rocking arms, other slots w at the upper ends of the arms v engaging the drum spindle d. The adhesive - wheels f are carried on the ends of rods e, which are mounted in slots in the drum spindle d so as to rotate with the drum and are normally held in retracted position, as shown in Fig. 1, by means of springs g, the ends of the rods e contacting with a bar h passing through the disks c. The means for depressing the bar h to project the adhesive wheels f into contact with the rear edge of the top sheet are shown in Figs. 3 and 4, and comprise a pair of end discs i mounted in fixed brackets r and formed with internal cams. When the drum reaches the limit of its backward motion, the bar h rides on the cams k and projects the adhesive wheels f. Each cam-disk i has a lug s projecting into a segmental slot in its bracket r so that a limited amount of rotary motion may be imparted from the disks c to the cam-disks i by means of spring plungers t engaging tapered stops u on the cam-disks for the purpose of maintaining the adhesive wheels in projected position during the first part of the next forward movement of the drum. Spring-mounted grippers p on the disks c are opened bv other cams m on the disks i at the same time as the adhesive wheels f are projected by the cams k, and seize the rear edge of the top sheet when it is lifted. The remaining sheets are held drawn by fingers 20 on a spindle 21 carrying spring- pressed arms 22 with a roller 23 adapted to be engaged by the brackets r to lift the fingers 20 when the next sheet is to be fed. The pile table b is automatically raised by means of chains 2 carried by sprocket-wheels 4, 5, the former of which is keyed to a spur-wheel 6 rotated through gears 7, 8, by a ratchet wheel 9 operated by a pawl 10 from a cam 12 on the rocking arms v. If the pile of sheets is too high, the drum spindle d contacts with a roller 19 on a hell-crank 17, which then swings another bell-crank 16 so that a catch 15 is depressed behind a projection 14 on the pawl 10 and prevents further lifting of the pile. Fig. 5 shows a duplicate feeding-device, in which a pair of skeleton drums c, c<1>, are carried by a single reciprocating slide 26, and feed sheets alternately from the piles a, a<1>, to a single feedboard 27, the drum c feeding its sheets direct to the rollers 30, 31, and the drum c<1> feeding its sheets to tape rollers 28 and thence along tapes 29 to the feed rollers 30, 31. The Provisional Specification also states that, instead of employing adhesive wheels of roller composition requiring to be damped, amber or like wheels charged with static electricity may be employed, means being provided for rubbing them just prior to their contacting with the edge of the sheet.