US2593180A

US2593180A - Sheet transfer device for perfecting presses

Info

Publication number: US2593180A
Application number: US604956A
Authority: US
Inventors: Howard A Pritchard
Original assignee: Harris Seybold Co
Current assignee: Harris Corp
Priority date: 1945-07-13
Filing date: 1945-07-13
Publication date: 1952-04-15
Anticipated expiration: 1969-04-15

Description

H. A. PRITCHARD April 15, 1952 SHEET TRANSFER DEVICE FOR PERFECTING PRESSES Filed July 15, 1945 HTTORN E Y6 Patented Apr. 15, 1952 UNITED STATES PATENT OFFICE.

SHEET TRANSFERrDEVICE FOR PERFECTING PRESSES" Ha aiian. Pritchard, Hiram, Ohio, assignor to Harris-Seybold Company, a corporation oi Delaware Application July 13, 1945, Serial No. 604,956

;. 4 Claims. (01. 101-442) endless conveyor provided with sheet gripping devices. I

. Another object is the provision of a press of the character stated, the printing units of which may be disposed comparatively close to the floor of the pressroom, and wherein a spacing of the units may be selected such that an operator's platform of commodious proportions may be mounted between the units.

A further object is the provision of an endless conveyor running under the operator's platform for transferring sheets from the first unit to the second unit.

Still another object is the provision of an endless conveyor for this purpose which runs over the impression cylinder of one unit and over an idler cylinder disposed in sheet transferring relation with the impression cylinder of the other unit, whereby the transfer means may beof any length desired but embodies a single idler for reversing the sheets.

Another object is the provision of 'a delivery means embodying an endless conveyor running directly over the impression cylinder of the second unit.

Other objects and features of novelty will appear as I proceed with the, description of that embodiment of the inventiohwhich, for the purposes of the present application, I have illustrated in the accompanying drawing, in which the single figure is a diagrammatic side elevational view of a sheet fed rotary perfecting offset printing press embodying the invention.

In the drawing l0 represents a pile of sheets to be printed. Means, not shown, are provided for separating these sheets one at a time from the top of the pile and advancing them onto a feed table II provided with tapes i2 which cause the sheets to travel down the feed table and into the bite of a pair of feed rolls l3 of known construction which feed the sheets one at a time into the B, each of which comprises a plate cylinder I4,

a transfer cylinder 15, and an impression cylinder IS. The corresponding cylinders of the two units may be substantially identical in construction. The plate cylinders I4 of both units are inked and dampened by inking mechanism 9 and dampening mechanism 11. These mechanisms may be identical in the two units, except that the directions of rotation are opposite and the dampening mechanisms are reversed in position. The three cylinders of each unit may be similarly disposed relative to each other. In each case they axes of the cylinders intersect a triangle, one side of which, herein termed the base, is greater than the other sides. In the drawing the base of the A triangle is numbered l8 and'that of the B triangle 19. Base 18 extends in a generally vertical direction, while base I9 is approximately horizontal.

The two units A and B are spaced apart far enough to accommodate between them an operators platform 20 of dimensions such that the operator may have adequate room for working upon unit A. V

The transfer of sheets from unit 'A to unit B is accomplished by an endless conveyor, and since this conveyor may be designed to occupy relatively little vertical space beneath the platform, the height of the machine in general may be kept at a minimum. This conveyor comprises a pair of chains, indicated by the broken line 2!, connected at the proper intervals by transverse bars 22. Each of these bars supports a series of transversely spaced sheet gripping fingers 23. In the illustrated case the chains 2| run over sprockets (not shown) at the ends of impression cylinder l6 of unit A, and over similar sprockets at the ends of an idler cylinder 24. Both of these cylinders I6 and 24 are provided with gaps which receive the transverse bars 22 one after another and with mechanism of known construction for holding the bars accurately positioned in the cylinders for so long as they are in contact therewith.

The perfected sheets are carried to a delivery pile 30 by means of an endless conveyor comprising a pair of chains indicated diagrammatically by the broken line 3|. These chains run upon sprockets (not shown) carried at the ends of cylinder iii of unit B and fixed with respect thereto. These chains also run over sprockets at the ends of a further cylinder, not illustrated, and over idlers required to make the chains take the course indicated in the drawing. The delivery conveyor as herein illustrated extends over the top of the inker 9 of unit B so as to leave that inker relatively free for inspection, servicing and 3 repair. This conveyor, like the transfer conveyor between units, comprises in addition to the chains 3| transverse bars 22 and gripper fingers 23. Cylinder l6 of unit B is provided with a gap for the. reception one after another of the bars 22 and their gripper fingers 23 carried by chains 3|. As a gripper bar and fingers of the transfer conveyor pass a corresponding gripper bar and fingers of the delivery conveyor, a sheet is transferred to the delivery conveyor, and is carried clockwise around cylinder [6 of unit B between that cylinder and the blanket cylinder l5 for printing the reverse side of the sheet, that is considering the imprint by the unit A to be upon the front of the sheet.- The sheet then continues to travel with the endless delivery conveyor over the top of the inker 9 and to the pile 39, where it is released and drops onto the pile.

It will be observed that the transfer conveyor embodying chains 2| runs over the impression cylinder of one printing unit and over an idler cylinder in sheet transferring relation with the impression cylinder of the other unit. The reversing of the sheet will be accomplished whether the idler cylinder, such as 24, be at the front or rear end of the conveyor. However, the illustrated arrangement is considerably to be preferred, because it leaves impression cylinder IE of unit B free to take the delivery conveyor embodying chains 3!. This arrangement embodies a minimum number of cylinders, namely one in addition to the three cylinders at each unit necessary for the printing operation. The, optimum in simplicity is thereby attained.

Having thus described my invention, I claim:

1. In a sheet fed rotary perfecting printing press, two printing units each comprising a printing cylinder and an impression cylinder, an operators platform between said units, and an endless conveyor for transmitting sheets from the first unit beneath the platform to the second unit, an idler cylinder in sheet transferring relation with the impression cylinder of one of said units, said conveyor running over the said idler cylinder and over the impression cylinder of the other unit.

2. In a sheet fed rotary perfecting offset printing press, two printing units each comprising an impression cylinder, an offset cylinder 3. In a sheet fed rotary perfecting offset printing press, two printing units each comprising an impression cylinder, an offset cylinder and a plate cylinder, an idler cylinder in sheet transferring relation with the impression cylinder of the second unit, an endless conveyor for transferring sheets from the first unit to the second unit, said conveyor running over the impression cylinder of the first unit and over said idler cylinder, and an endless delivery conveyor running over the impression cylinder of the second unit.

4. A sheet fed rotary perfecting offset printing press, comprising two separate printing units each having an impression cylinder, an ofiset cylinder, and a plate cylinder, the axes of the cylinders of each said unit intersecting the points of a triangle, the base of which is longer than the sides thereof and joins the impression and plate cylinders, the offset cylinder of each unit being disposed on that side of its impression cylinder which is remote from the feeding end of the press, the base of the triangle of the first unit being substantially vertical and the second triangle being inverted with its base above the transfer cylinder of that unit, means for feeding sheets into the pressthrough the base of the first unit triangle toward the offset cylinder of that unit, an endless sheet conveyor for transferring sheets from the first unit to the second unit, an idler cylinder in sheet transferring relation with the impression cylinder of the second unit, said conveyor running over the impression cylinder of the first unit and over said idler cylinder, the cylinders of the second unit being driven in a direction to feed sheets through the base of the second triangle in a direction away from the transfer cylinder of that unit, and an endless delivery conveyor running over the impression cylinder of the second unit extending upwardly from that cylinder.

HOWARD A. PRITCHARD.

REFERENCES CITED The following. references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,310,506 Scott July 22, 1919 1,849,219 Belluche Mar. 15, 1932 2,100,852 Jacobson Nov. 30, 1937 2,138,407 Huck Nov. 29, 1938 2,174,865 Barber Oct. 3, 1939 2,245,343 Hunting June 10, 1941 2,360,340 Harris Oct. 17, 1944 2,374,668 Davidson May 1, 1945