Patent GB-190316081-A (GB)
Title: Improvements in and relating to Pneumatic Sheet-feeding Machines
Inventor: BENEDICT LEWIS
Filed: 1903-07-21
Granted: 1903-09-10
Abstract: 16,081. Lake, H. H., [Benedict, L.]. July 21. Feeding sheets.-A pneumatic apparatus for use in feeding sheets is provided with a conical or other suitable rotary valve 34, Fig. 4, by means of which the various sheet - lifting and forwarding mechanisms may be controlled, and with a slow-return carriage for the front sheet - lifting mechanism, for the purpose of allowing the complete passage of the back end of the advancing sheet past the front pickers before they are in position to be lowered upon the pile of sheets. The sheets 10 are supported by a table 9, which is mounted on a standard 8 and raised in any well-known way so as to keep the top of the pile at a constant level during the feeding of the sheets. A vacuum chamber 14 is connected by a pipe 16 to any suitable air pump, and supports a valve - box 20, Fig. 4, within which is the valve 34, rotated continually by means of bevel gearing 33 and chain gearing 32 from the main shaft 11. The lower end of the valve is open and communicates with the chamber 14, its upper part is closed, and in its sides are apertures at three different levels ; one aperture registers with a pipe 24, another with a pipe 25, and between these are a single aperture 39, Fig. 6, and a series of closely placed apertures 40, all arranged to register with a pipe 26. If desired, a slot may be formed in the valve instead of the apertures 40. During the rotation of the valve, the pipes 26. 24, 25 are put successively in communication with the vacuum chamber 14. The front sheet-lifting and forwarding mechanism comprises a carriage 45 mounted to slide upon bars 44 at the sides of the machine and actuated by means of a bell-crank lever 48 and cam secured to the shaft 11 ; this cam is shaped so as to give a quick forward movement to the carriage, and a slow return movement. The carriage comprises two slide-blocks connected by a cross-bar, upon which are splined blocks 53 carrying the front sheet-lifting tubes, Fig. 8. Upon each block 53 is a tube 54 connected by a flexible tube 55 to the pipe 24 ; a valve 57, of any suitable construction, is fitted to the tube 54 and is automatically opened when the carriage has nearly completed its forward stroke, and closed when the carriage makes its return stroke. A telescopic lifting-tube 62, with a suitable cup 63, is mounted on the lower end of the tube 54. A cylinder 64, carried by the block 53, is connected by means of a flexible tube 65 with the tube 25, and is fitted with a piston connected to a sliding-rod 69, the lower end 74 of which is bent and forked to engage with the tube 62. When, during the rotation of the valve 34, communication is opened between the cylinder 64 and chamber 14, a vacuum is formed beneath the piston 67 of the cylinder, and the rod 69 is, in consequence, forced downwards, against the pressure of a spring 72, thus allowing the tube 62 to fall freely upon the sheets. When the communication between the cylinder 64 and vacuum chamber is cut-off, the spring 72 is permitted to lift the rod 69, by reason of air passing slowly into the cylinder through a very small aperture 75. The rear sheet-lifting apparatus comprises telescopic tubes 86, each with its cup 87, connected to a tube 84 communicating by means of a flexible tube 85 with the tube 26. When the top sheet has been lifted by the tube 86, a current of air is blown beneath it by a blower 82 communicating by mean= of a pipe 81 with an air pump driven by gearing from the shaft 11 ; the rear end of the sheet is then released by the tubes 86, and the sheet is carried forwards by the carriage 45 towards the feeding-mechanism, the front end of the sheet having been lifted by the cups 63 of the front lifting-apparatus. The feeding-mechanism comprises a series of endless tapes 93, wbich travel beneath a roller 95, and the carriage 45, during its forward stroke, introduces the sheet between the roller 95 and the tapes.