US2591116A - Sheet separating and forwarding machine - Google Patents

Description

April 1, 1952 BACKHOUSE 2,591,116

SHEET SEPARATING AND FORWARDING MACHINE Filed April 21, 1949 2 SHEETSSHEET l wwww April 1, 1952 H. T. BACKHOUSE SHEET SEPARATING AND FORWARDING MACHINE Filed April 21, 1949 2 SHEETS-SHEET 2 Patented Apr. 1, 1952 UNITED STATES PATENT OFFICE SHEET SEPARATING AND FORWARDIN G MACHINE Headley Townsend Backhouse, Sunningdale, England 6 Claims. 1

The invention relates to sheet separating and forwarding machines of the kind (herein referred to as the kind described) in which a suction gripper operating at or near the rear edge-considered in relation to the ultimate direction of forwarding the sheetsof the upper surface of a pile of sheets of paper, card or other material, is lowered into gripping engagement with each uppermost sheet of the pile in turn and is then, while gripping a rear portion of the sheet, raised and given a movement over the top of the pile towards the front of the pile to forward, or to control the forwarding of, the sheet to conveyor or like means (e. a, rollers gripping the front edge of the sheets) for removing the sheet from the pile, the suction gripper then releasing the sheet and returning to the initial position to engage the next sheet of the pile. Machines of this kind may be arranged to feed the sheets singly or in the form of a stream of partly overlapping or partly underlapping sheets and may be employed to feed the sheets to a printing or other machine operating on individual sheets. It is an object of the invention to provide an improved form of machine of the kind described of relatively simple construction and of high operating speed.

The invention provides a machine for separating individual sheets one at a time from the top of a pile and for forwarding the sheets from the pile and comprising asuction gripper operating adjacent the rear edge of the upper surface of the pile and having an open mouth for suction engagement with the sheets, a co-operating piston and cylinder with an operative connection to the gripper arranged for suction operation to effect raising and lowering of the gripper, means for moving the gripper, when raised, back and forth over the pile, a conduit leading from the gripper mouth to the cylinder, a valve in the conduit having a port leadingto the atmosphere and means for operating the valve, the machine being arranged for operation in a cycle in which the gripper is lowered into engagement with the uppermost sheet with the conduit open, the port aforesaid closed and suction applied to the cylinder so that the closing of the mouth of the gripper by the sheet seals the cylinder from the atmosphere and enables the suction to build up in the cylinder to effect relative movement between the piston and cylinder to raise the gripper with the rear portion of the sheet; the raised gripper is moved in the forwarding direction over the top of the pile, the valve is then operated .to open the port and to close the conduit thereby to open the gripper mouth to atmospheric pressure to release the sheet and to maintain the suction in the 0371- inder; the gripper is then moved back over the pile; the valve is operated to open the conduit thereby to admit air to the cylinder and the gripper is then lowered to begin a new cycle.

In this specification, where appropriate, and in the appended claims, the term piston and cylinder is used to include the equivalents of a diaphragm and chamber or collapsible bellows.

In the preferred form of the invention the gripper is carried by the movable element of the piston and cylinder to effect the raising and lowering of the gripper and the piston and cylinder are arranged for bodily reciprocation or oscillation to efiect the movements of the gripper over the pile.

The cylinder may be continuously connected during the cycle to a source of suction.

A specific embodiment of a sheet separating and forwarding machine according to the invention will now be described by way of example and with reference to the drawings in which:

Figure 1 is a side view, partly in section, of the machine, and

Figure 2 is a view showing the cylinder and valve in three positions.

The machine forming the subject of the example and shown in Figures 1 and 2 has two lifting and forwarding units l positioned in spaced relation above the rear ed e 2 of the pile 3 of sheets and supported from a common bar 4 of square section extending transversely across the pile. The two units are of similar construction and for the sake of clarity the following description relates to only one of the units.

Depending from the above-mentioned square section bar 4 there is a bracket 5 which is adjustably clamped (by plate 6 and screws 1) to the bar for sliding adjustment along the length of the bar. The depending portion of th bracket is forked and embraced within the arms of the fork there is a cylinder Zlll having its mouth directed downwardly and supported at its uppper end by a rocket shaft 203 below and extending parallel to the square section bar. The shaft is supported in the two arms l2 of the bracket and in operation has. oscillatory movements imparted to it by means forming no part of the present invention.

The cylinder 2!, above thepiston, is continuously open to a source of suction through the hollow shaft 203 from which the'cylinder is dependent. The piston is urged outwardly of the cylinder, 1. e. in the downward direction, by a spring 204 and the lower end of the cylinder is open through holes 205 to atmospheric pressure.

and there is between the two portions a layer of REFERENCES CITED resilient material urging the Forums apart into The following references are of record in the fricgionaldand sealing engagement with the walls file of this patent: of t e gui eway.

6. A machine as claimed in claim 1 in which 5 UNITED STATES PATENTS the gripper is held raised during the backward Number Name Date stroke by the suction in the cylinder. 2,085,612 Spiess June 29, 1937 2,224,802 Spiess Dec. 10, 1940 HEADLEY TOWNSEND BACKHOUSE. 2,341,521 Baker et a1. Feb. 15, 1944

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