US2734744A

US2734744A - Sheet feeding machines

Info

Publication number: US2734744A
Authority: US
Publication date: 1956-02-14
Anticipated expiration: 1973-02-14

Description

1956 H. T. BACKHOUSE SHEET FEEDING MACHINES 3 Sheets-Sheet 1 Filed Oct. 31, 1951 INVEN To R Arrakue'vs 1956 H. T. BACKHOUSE I 2,734,744

SHEET FEEDING MACHINES Filed Oct. 51, 1951 3 Sheets-Sheet 2 Arr-121v! Feb. 14, 1956 H, BACKHQUSE 2,734,744

SHEET FEEDING MACHINES Filed Oct. 31, 1951 5 Sheets-Sheet 3 Iva/v11},

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Uflitfrd States 2,734,744 r I SHEET FEEDING MACHINES Headley Townsend Backhouse, Nassau, Bahamas, British West Indies Application October 31, 1951, Serial No. 254,026

Claims priority, application Great Britain November 2, 1950 6 Claims. (Cl. 271-62) The invention relates to machines for feeding paper and like sheets to printing or other machines,and is concerned with sheet feeding machines of the kind (herein referred to as sheet feeding machines of the kind described) having primary and secondary elevating means by which a pile of sheets may be elevated to devices for removing the sheets one by one from the top of a pile, the rate of elevation being so controlled as to maintain the top of the pile at a substantially constant height, and the elevation of the pile being effective initially by the primary means and the pile then being transferred to the secondary means which continues the elevation so that the primary means may be lowered to take a fresh pile whereby a substantially continuous supply of sheets may be made available to the removing devices, the primary and secondary elevating devices each comprising lifting chains, wires, racks or the like at the front and back of the machine and primary and secondary crossbars interconnecting the chains or the like, and arranged to support a pileboard carrying the pile, and the machine also having stacking gauges by which the front of each pile is positioned and is guided as the pile is elevated. The sheets removed from the pile by the removing devices are usually fed to the printing or other machine by conveyor means. It is also usual that there are devices associated with the conveyor means or the printing machine for obtaining exact registration of the sheets. One example of a sheet feeding machine of this kind is disclosed in United States application Serial No. 718,201, filed December 24, 1946, now abandoned.

One object of the present invention is to improve the adaptability and simplicity of operation of machines of the above kind. 7

In some installations of machines of the kind described it is necessary or convenient to insert the piles of sheets to be elevated into the machine from the back of the machine (considered in relation to the direction of removal of the individual sheets) and in other installations it is necessary or convenient to insert the piles of sheets from one side of the machine. A more specific object of the invention is to provide one construction of machine which may readily be adapted for insertion of the piles from the back or from the side.

The invention consists of a sheet feeding machine of the kind described characterised by the features that, as viewed from the side of the machine, the primary elevating chains or the like are outside the secondary elevating chains or the like, the primary elevating chains or the like at the front of the machine are in front of ,the stacking gauges (i. e. on the side of the gauges remote from the pile) and the primary supporting crossbars extend in the fore and aft direction.

Preferably both the primary and the second elevating chains or the like, as viewed from the rear of the machine, are outside the position whichwould be occupied by a pile of the maximum width for which the machineis constructed.

ICC

another form of this arrangement the pile carrying means have projections extending forwardly between the front stacking gauges to rest on the secondary support bar. The pile carrying means may be in addition to a pileboard and may be arranged to be withdrawn rearwardly of the machine.

The primary elevating means may comprise two chains at each side of the machine, and the two chains at each side may be supported on sprocket wheels carried on a shaft at that side and extending in a fore and aft direction. The secondary elevating means may also comprise chain and supporting sprocket wheels on a shaft arranged like the primary means, and the primary and secondary supporting shafts at each side may be concentric. In machines of the kind described it is necessary to transfer a support board or a set of supporting strips from the primary to the secondary elevating means to constitute a support for the pile, and it is necessary, when the pile is exhausted or shortly before exhaustion, to withdraw the support. The arrangement just described, permits a support board having a straight front edge, normally resting against the stacking gauges, to be employed thereby facilitating withdrawal of the board to one side of the machine should that be desired. Preferably the board is divided in its width into two parts which may be withdrawn from opposite sides of the machine.

Three specific constructions and arrangements of machines according to the invention will now be described by way of example and with reference to the drawings which are largely schematic and in which:

Figure 1 represents a perspective view of one of the machines,

Figure 2 is a perspective view similar to Figure 1 but showing an alternative arrangement of the machine,

Figure 3 is a perspective view showing the upper part of the third construction of the machine, and

Figure 4 is a side view of the machine shown in Figure 3, including the lower part.

Each ofthe machines forming the subject of these examples is arranged to elevate a pile 1 of sheets to mechanism (not shown) for separating each uppermost sheet from the pile in turn and for forwarding the sheet to a tape conveyor 2, the conveyor taking the separated sheets to a printing or other machine.

In the machine shown in Figure 1 there is at each side of the machine primary and secondary elevating means.

It is also preferred that the secondary chains or the The arrangement of the two sides is similar and for the sake of clarity the following description relates only to the arrangement at one side.

At the top of the machine there is a pair of nested concentric shafts extending in the fore and aft direction. The inner shaft 3 is of solid form and the outer shaft 4 is in the form of a sleeve shorter than the inner shaft and arranged so that the inner shaft extends therefrom at both ends. The inner shaft 3 is allocated to the primary chains 5, 6 and the sleeve 4 is allocated to the secondary chains 7, 8. The inner shaft 3 carries adjacent to its ends two sprocket'wheels 9, 10 over which the primary elevating chains 5, 6 pass. The chains 5, 6 hang freely from the sprocket wheels 9, 10 and one end of each chain is attached to a support bar 11 on which a pileboard 12 may be'supported, the bar 11 extending in the fore and aft direction. The other end of each chain 5, 6 is provided with a' counterbalance weight 13 which assists in maintaining the chain 5 6 in position on its sprocket wheel 9, 10.

At the ends of the outer shaft 4 there are sprocket wheels 14, over which the secondary chains 7, 8 pass, the arrangement of the secondary chains 7, 8 being similar to that of the primary chains 5, 6 with the exception that the spacing between them is less and the support bar16 is correspondingly shorter.

Each inner shaft 3 and each outer shaft 4 at the two sides of the machines carries a

worm wheel

18, 19. The two wheels 18 are interconnected by a cross-shaft 20 carrying worms 21 engaging the wheels 18 so that rotation of the cross-shaft 20 effects simultaneous rotation of the shafts 3. Similarly the worm wheels 19 are interconnected by a cross-shaft 22 carrying worms .23 engaging the wheels 1% so that rotation of the cross-shaft effects simultaneous rotation of the outer shafts 4.

The machine is provided with vertically extending front stacking gauges 25 which serve to locate the front edge of the pile 1 during the insertion of the pile and also during its elevation. The primary chains 6, the secondary chains 8 and the supporting

sprocket wheels

10, 15 are in front A of the pile stacking gauges 25.

At the top of the machine there is a horizontal flap 26 (shown more clearly in Figures. 3 and 4) for the purpose of leading the front edge of the sheet to the conveyor and for correcting any displacement of the remaining sheets, the flap moving against the pile for that purpose.

In use a pileboard 12 is loaded on to the support bars 11 and a pile of sheets 27 is built up on the board 12, the front edge of the board 12 and the front face of the pile 27 abutting the front stacking gauges 25. In an alternative method of use a pileboard 12 complete with pile is first placed in position against the front stacking gauges 25, and the primary chains 5, 6 and bars 11 are lowered and the bars 11 engaged underneath the pile board 12. The inner driving shafts 3 are then rotated by means of the cross-shaft 20 and worm drive to elevate the piie by means of the primary chains 5, 6. The rate of elevation is controlled in known manner to maintain the top of the pile at a substantially constant height as the sheets are removed. When the pileboard 12 has reached a convenient height the secondary support bars 16 and the secondary elevating chains 7, 8 are swung outwardly to clear the edge of the pileboard 12 and are then engaged underneath the board. The secondary elevating means are then operated to continue the elevation of the pile while the primary chains 5, 6 and support bars 11 are lowered ready to receive and elevate a new pile. When the new pile is ready the primary means are operated (e. g. manually or electrically) to bring the top of the new pile into engagement with the underside of the pileboard 1.2 supporting the preceding pile. The elevation of the two piles is the continued by the primary means. When the first pile is nearly exhausted the upper pileboard is removed in the sideways direction, the remainder of the pile falling onto the top of the new pile. The secondary elevating means are then lowered to receive at the appropriate time a fresh pile and board supported by the primary means. The transfer to the secondary means is effected when the board has reached a height which enables another pile to be built or inserted beneath the board. To effect the transfer the secondary support bars 16 are swung clear of the edges of the board, are lowered beneath the board and raised to engage the board so as to take over the supportof the board from the primary means in the manner already described.

To assist in the removal of the pileboard with a minimum of disturbance of the sheets strips of smooth material (e. g. flexible plastic material) are placed between the board and the pile it supports and also between the top of the new pile and the underneath of the board. These strips have their ends extending from the pile and turned to lie against the face of the pile and during the removal of the board the ends may be supported, e. -g. against support bars or the equivalent. M

. the projections.

In the alternative construction shown in Figure 2 the pileboard 30 has a width, as viewed from the back of the machine, less than the space between the support bars 11 and the board is placed on pile irons 31 carried on the support bars 11 and extending between them. The secondary support bars 32, 33 extend crosswise of the machine and the bar 33 is in front of the front stacking gauges 25, i. e. on the side of the gauges remote from the pile. The machine includes a side stacking gauge 34.

in the operation of this arrangement of the machine a set of strips 35 is inserted between the pile 27 and the pileboard 30, the ends of the strips 35 projecting forwardly between and outside the front stacking gauges 25. The pile is initially elevated by the primary elevating means and when it reaches a convenient height the secondary support bars 32, 33 are swung outwardly to clear the ends of the strips 35 and are then engaged underneath the strips. The secondary elevating means are then operated to continue the elevation of the strips 35 and the pile carried thereby while the primary elevating means and the pileboard 30 are lowered ready to receive and elevate a new pile. When the new pile is ready the primary means are operated to bring the top of the new pile into engagement with the underside of the strips of the preceding pile. The elevation of the two piles is then continued by the primary means until the first pile is nearly exhausted when the strips are removed in the rearwards direction, the remainder of the first pile falling back on to the top of the lower pile.

In the machine shown in Figures '3 and 4 the primary elevating means are constructed and arranged for operation in the manner just described with reference to Figure 2. The secondary elevating means have support bars 40, 41 which extend crosswise of the pile, the bar 41 being in front of the front stacking gauges 25. The support bar is provided with a single pawl 42 pivoted to the bar 40 extending along the full length thereof. The support bar 41 has four individual pawls 43 pivoted to the bar 41 which project to the rear of the stacking gauges 25. The support bar 40 is backed by guide strips 44, and the support bar 41 is guided in slots 45 in guide bars 46. The pileboard 48 rests. on the pawls 42 and 43 and is, in this construction, divided in the fore and aft direction of the machine into two parts of equal width.

In the operation of the machine shown in Figures 3 and 4 a pile and pileboard are loaded on to the primary elevating means as described with reference to Figure 2 except that the strips 35 are omitted. The primary elevating means are elevated until the pileboard 48 engages and deflects the pawls 42, 43, which pawls fall back heneath the board 48. The secondary elevating means are then operated to elevate the pileboard 48 by engagement of the pawls 42, 43 with the board 48.

As in the previous examples a second pile is built on the primary elevating means and is raised to engage the underside of the first pile and to continue the elevation thereof. Figure 4 shows the arrangement just before the second pile engages the board of the first. When the first pile is nearly exhausted the two portions of the pileboard are removed in the sideways direction of the machine as indicated in broken lines in Figure 3.

In each of the above examples both the primary and the secondary elevating chains as viewed from the rear of the machine are outside the position which would be occupied by a pile of the maximum width for which the machine is constructed.

It is within the invention to modify the arrangement shown in Figures 3 and 4by replacement of the pawls on the front secondary support bar by fixed lips or projections which project rearwardly beyond the stacking gauges. With this modified arrangement the guide bars 46 are arranged to permit forward movement of the support bar to enable the pileboard to move upwardly past For this purpose the guide bars are pivoted at their upper ends about an axis transverse to the machine. The support bar 40 may be similarly arranged.

I claim:

1. A sheet feeding machine comprising a front stacking gauge for locating the front of a pile of sheets within the machine, a pile-board for carrying a pile of sheets engaging said gauge, primary means for elevating said pileboard including at each side of the machine at the front and back thereof vertically extending members, a subframe carried by the members and means for raising said members, said pile-board being carried by said Sub-frame and located wholly between said elevating members as viewed from the side of the machine and between said elevating members at the back as viewed from the back.

of the machine, secondary means for elevating a pile of sheets and the pile-board supporting it transferred thereto from the primary supporting means, said secondary elevating means including vertically extending elevating members at the front and back of the machine at each side thereof, means for raising said secondary elevating members, and two pile-supporting-cross-bars extending transversely of the machine between said two secondary elevating members at the front and back respectively, said front secondary elevating members and said front crossbar being in front of the said front stacking gauge and having projections extending to the rear side of said gauge adapted to support a pile-board on the rear side, and said back cross-bar having pile-board supporting means projecting beyond the front of said rear elevating members.

2. A sheet feeding machine as claimed in claim 1, in which the sub-frame aforesaid comprises two pilesupporting side bars one at each side of the machine and attached to the front and back members, and two spaced cross-bars extending transversely of the machine and attached to the side bars intermediate between the elevating members, the cross-bars being arranged to carry an unattached pile-board seated thereon.

3. A sheet feeding machine as claimed in claim 1, in which the rearward projections aforesaid from the front secondary cross-bar are constituted by pawls pivoted to the cross-bar for upwards and forwards movement and having means preventing downwards pivotal movement beyond a pile-supporting position.

4. A sheet feeding machine as claimed in claim 1, and including a pile-board constructed to seat on the projections and pile-board-supporting-means aforesaid and divided in the fore and aft direction into two parts.

5. A sheet feeding machine as claimed in claim 1, in which the primary and the secondary elevating members are chains, in which the means for raising the members comprise, for each chain, a sprocket wheel from which the chain is directly dependent, the sprocket wheels for the primary chains at each side of the machine being secured to a supporting shaft extending in the fore and aft direction, the sprocket wheels for the secondary chains at each side of the machine being secured to a second supporting shaft also extending in the fore and aft direction, and the primary and secondary shafts at each side being in coaxial nested relation.

6. A sheet feeding machine as claimed in claim 3, and including guides for the secondary cross-bars constraining the cross-bars to move vertically.

References Cited in the file of this patent UNITED STATES PATENTS 912,563 Gustafson Feb. 16, 1909 2,204,985 Foweraker June 18, 1940 2,247,466 Baker' July 1, 1941 2,368,094 Baker Jan. 30, 1945 2,549,364 Bobst Apr. 17, 1951