US2650705A - Method and apparatus for handling paper - Google Patents

Description

Sept. 1,,1953 H.T. RANDALL 2,650,705

' METHOD AND APPARATUS FOR HANDLING PAPER Filed Aug. s, 1946 4 Sheets-Sheet 1 INVENTOR ATTORNEY Sept. 1, 1953 H. T. RANDALL 2,650,705

METHOD AND APPARATUS FOR HANDLING PAPER Filed Aug. 5, 194a 4 Sheets-Sheet 2 INVENTOR ATTORNEY Sept. 1, 1953. H. T. RANDALL 2,650,705

um mn AND APPARATUS FOR matin Pa I Filed Aug. 5, 1946 4 Sheets-Sheet 3 INVENTQR BY fizz/hf 7 2 4 ATTORNEY Sept. 1, 1953 l H. T. RANDALL 2,650,705

METHOD AND APPARATUS FOR HANDLING PAPER Filed Aug. 5, 1946 4 Sheets-Sheet 4 INVENTOR ATTORNEY Patented Sept. 1, 1953 METHOD AND APPARATUS FOR HANDLING PAPER Herbert '1. Randall, Hamilton, Ohio, assignor to The Champion Paper and Fibre Company, Hamilton, Ohio, a corporation of Ohio Application August 5, 1946, Serial No. 688,432

14 Claims.

This invention relates to the handling of paper in sheets, particularly in operations such as that of sorting the paper to eliminate defective sheets, and subsequently trimming the sheets to size preparatory to packing for shipment to the user, or in other operations wherein sheets are alternately handled individually and in piles.

It is common practice in the manufacture of the better grades of printing paper, when cutting the paper into sheets, to stack the sheets on skids and truck them into the sorting room where the operators examine each sheet separately for defects, usually on both sides, stacking the perfect sheets in a pile which is placed on another skid which is then trucked to the trimmers, or to storage space where it awaits its turn at the trimmers, or directly to the shipping room if the paper is not to be trimmed. Likewise, the defective sheets are stacked in another pile, placed on another skid which is then trucked away for disposition in accordance with its quality and the customs of the particular mill. They are sometimes again sorted into two grades-seconds and waste. In this method of handling and sorting, each operator normally has three piles of paper, one unsorted, one perfects, and one defective. Wide trucking aisles and storage spaces must be provided for those skids being moved to or from such operation or awaiting sorting, transportation, trimming, or other disposition. For each skid of paper sorted, the truckers must bring in one full and two empty skids and remove one empty and two at least partially filled skids. This tends to create congestion and to interfere with the work of the sorters, and frequently results in damage to the paper on the skids due to the frequent necessity of maneuvering trucks in close quarters. Conveyors have not been generally used instead of trucks for this work, partly because of the difiiculties involved in placing the sheets of paper, after individual handling, onto a moving conveyor in piles or lifts of a height and character which can be satisfactorily handled at the discharge end.

One object of the present invention is, therefore, to reduce the amount of handling, time, labor, and floor space required to bring paper sheets to operations where they are handled individually, as in sorting, and to transport them from these operations to the place of some subsequent operation or other disposition. Another object is to provide methods and apparatus whereby sheets of paper can be carried away in piles of lifts on a continuously moving conveyor from an operation wherein they have been handled individually. A further object is to provide means whereby an operator handling sheets individually can stack them in orderly piles and readily transfer each pile to a continuously moving conveyor when the pile has reached the desired height. A still further object is to provide means whereby a, plurality of operators can form sheets into such piles or lifts and each operator transfer the lifts so formed, onto the same continuously moving conveyor, for transportation to the location of the succeeding operation. Other objects and advantages of the invention will become apparent from the following detailed description.

These objects can, I find, be successfully accomplished by providing a belt or equivalent type of conveyor for transporting the sorted paper to the trimmers, or to other place of disposition, by arranging the sorting tables along one side of this conveyor, by providing temporary sheet receivers or platforms composed of closely spaced rollers, freely rotatable on axes extending crosswise of the belt, which platforms are arranged a few inches above the belt and adjacent the respective sorting tables. The objects can be more perfectly accomplished by providing a second belt conveyor for transporting the defective sheets to a place of disposal at a location distinct from that to which the perfect sheets are transported. Or, more conveniently in some cases, two additional conveyors can be provided, instead of one, one for transporting seconds to a place of disposition and another for disposing of sheets which are unusable and constitute waste.

The invention will be more fully described with reference to the accompanying drawing in which:

Figure l is a more or less diagrammatically plan view showing the arrangement of trucking lane, sorting tables, belt conveyors, trimmer, and place of delivery of defective sheets.

Figure 2 is a similarly diagrammatic elevational View of the same; wherein the part below the floor line is shown in section along the center line of the sorting tables.

Figure 3 is an elevational view to a much less reduced scale of one of the sheet receiving roller platforms and a portion of a conveyor belt showing how a lift of sheets is transferred from the platform to the conveyor.

Figure 4 is a cross-sectional view on the line 44 of Figure 1.

Figure 5 is a plan view similar to Figure 1 but showing the provision of two conveyors for defective sheetsone for seconds and one for waste.

Figure 6 is an elevational view of the same 3 wherein the part below the floor line is shown in section along the center line of the sorting tables.

Figure '7 is a cross-sectional view on the line l'|' of Figure 5.

Referring first to the embodiment illustrated in Figures 1 to 4, an endless conveyor belt H is supported on carrier rolls l2 and passes around end rollers l3, [3, one of which may be used to supply the driving force from a source of power, not shown, in a well-known manner.

A plurality of sorting tables I5 is provided. These are arranged along the side of conveyor I l and spaced at intervals sufiicient to allow a sorter to stand beside the belt II at the end of each table. These tables are advantageously arranged to be raised and lowered by any suitable type of device such as pistons it in hydraulic cylinders l'l. They are conveniently arranged to be lowered into recesses l8 to a position flush with the floor so that trucks may be run over them and skids 20 carrying paper 2 I, loaded onto them. They are also arranged to be raised by the same mechanism, to bring the top of the pile 2| of paper to the approximate level of the conveyor for ease in sorting and handling the individual sheets.

Arranged above conveyor belt H is a sheet receiving platform 25 corresponding to each of the sorting tables [5. As shown most plainly in Figure 3, these platforms are composed of a multiplicity of freely rotatable rollers 26 mounted at right angles to the direction of travel of belt il, in a suitable framework 21. The rollers 26 are advantageously of relatively small diameter and spaced closely together. There is no specific limitation as to size except the limitations of strength and stiffness 0n the one hand and of available space and paper span between rolls on the other. I have found 7 inch diameter rolls spaced on one inch centers to be suitable, though with rollers of this size, a central support with a set of rollers on each side, as indicated in Figures l and 4, may be desirable if the sheets to be handled are of considerable width.

The height h of the receiving platform 25 above the belt i I is, I find, a matter of considerable importance and may constitute the difference between practical success and failure. If there is only one such platform, it can be located as close to the belt H as desired and little difficulty need be encountered in transferring paper from it to the conveyor. However, one of the chief uses of the conveyor system herein described is to transport lifts of paper from a plurality of sorters to a common destination by means of a single conveyor. In .order that this may be possible there must be suiiicient clearance c between the belt and the lower surface of the framework 2? of platform 25 to permit the pas sage of lifts of paper of practical height, say between two and six inches. The maximum practical height of the top of the platform 25 depends on a variety of factors, such as the flexibility of the paper to be handled, the length of sheet, the friction of the paper moving over the platform, the speed with which it is pulled from the platform, and the speed of the belt, which, in turn must be kept within reasonable limits of not over 150 or 200 feet per minute, and advantageously nearer 100 to 120 feet per minute, in order to improve the operation at the discharge end. Of these factors, the belt speed has the greatest effect on the permissible height h. A rough rule is that the height h of the platform above the belt, measured in inches, should not exceed about one tenth of the numerical value of the belt speed measured in feet per minute. For handling short sheets and flexible paper, however, the height h is advantageously not more than half this amount. The shorter the length of the sheets to be handled, the less the maximum permissible value of the height h which should never be as much as half and is advantageously not over one fourth to one sixth of the sheet length, partic ularly with highly flexible paper. The less the friction of the paper moving over the rollers 26,

the lower the maximum safe value of the height h. The rollers 26 are preferably provided with anti-friction bearings, and within these limits, the friction of these rollers on their bearings has .no very significant effect on the height it. However, the softness of the lift of paper effects the value of the rolling friction and thereby the safe value of the height h. When the height of platforms above the belt is herein referred to as being a short distance, it is to be understood as a distance conforming to the foregoing limitations.

in order to secure a satisfactory transfer of the lift from the platform to the belt it must be pulled from the platform at a speed materially less than that of the belt and accelerated to approximately belt speed by the time the forward end rests on the belt as illustrated in Figure 3.

In practice heights h of much less than four inches leave too little clearance 0 below to pass satisfactorily thick lifts of paper, when there are several platforms arranged to discharge onto the same belt. Likewise, heights greater than ten inches will seldom, if ever, be required, since this makes possible more than enough clearance c to pass lifts of the maximum thickness which can be handled on the usual trimming machines, and is so far above the belt as to cause difhculty in transferring sheets therefrom to the belt except under unusually favorable conditions. I For the handling of sheets of paper from 30 to 66 inches in length, having a basis weight between about 40 and pounds per ream (25 x 38-500 sheets) and a thickness between about 0.002 and 0.004 or 0.005 inch, a height h of about 5 inches and clearance c of about 3 inches, is satisfactory with a belt speed of about feet per minute. This, it will be seen, satisfies the above stated requirements. Measured in inches it is one-twentieth the belt speed in feet per minute. It is within the desirable limit of one-sixth of the minimum expected sheet length. The clearance below the platform framework 21 is sufficient to pass lifts of one ream (500 sheets) each of the thickest of the expected sheets, with ample clearance to allow for curled edges or the like.

The paper supporting surfaces of these platforms are substantially horizontal, that is, they do not slope in the direction of belt travel to an extent which would permit the pile of sheets to move off of the platform by the action of gravity alone, and do not slope in the reverse direction an amount SllfilClBIlt to impede the transfer of the sheets to the belt.

Above the platform 25 are two guides for 10- cating the pile of paper to be built up on the platform and facilitating formation of a smooth straight pile. Guide 28 is fixed in a position parallel to the direction of travel of the belt, and guide 29 is fixed in a transverse direction. If different sized sheets are to be stacked on the same platform, these guides are preferably made adjustable in accordance with known practices.

At the discharge end of the belt H is a receiving table 3|, which is advantageously of fixed height and flush with the top of the table of a known type of trimming machine 32. It may be constructed of rollers as are platforms 25 or have a smooth sliding surface like the table of the trimming machine. If the number of sorting tables l5 or the amount of work to be done on each pile by the trimmer (as in cutting large sheets into a large number of smaller sheets), is so great that one trimmer cannot keep up with the sorters, more than one trimmer can be located adjacent to table 31 so that the paper delivered to the table by the conveyor H can be divided between the trimmers.

For disposing of defective sheets I provide below the belt ll, another conveyor belt 4| supported by carrier rolls 42 and end rollers 43. This belt advantageously, though not necessarily, travels in a direction opposite to that in which belt II is travelling. At the discharge end is a receiving table 45 which may, if desired, be of the hydraulic type raised and lowered by a piston A6 operating in hydraulic cylinder 41 and adapted to be lowered into recess 48 in order to bring the top of the table to a position flush with the floor to facilitate the placing and removing of paper receiving skids and to leave the floor unobstructed when the table is not in use. Guides 49 and 50 (Figure 4) are provided for facilitating the placing of defective sheets onto this belt ll.

With the apparatus as described, the operation is carried out as follows: by means of any suitable trucks, skids 20 of paper 2| are placed on the tables [5 or as many of them as are to be used. The sorters stand to the left of the tables I5 as illustrated in Figure 1, and face the tables with the conveyor H at their left. Each sorter examines the sheets for defects turning each perfect sheet over to the left onto the adjacent platform 25 advantageously pressing a mechanical counter in the operation. These sheets are carefully slipped into position against the guides 28 and 29 and as the pile grows the sheets are spattered up into a smooth pile and the usual ream markers are inserted, all in the manner familiar in the paper sorting operation. This pile of perfect sheets is built up to a suitable height not over about six inches and usually about half that height-at any rate low enough to pass under the platforms 25. The pile contains, preferably, an integral number of reams, half reams, or other units of count in which the paper is to be delivered. Such a pile or lift, if the sheets are large, as is usually the case when the sorting operation is carried out, may weigh as much as several hundred pounds and be extremely difiicult to transfer from a stationary table to a moving belt without damaging some of the sheets or disarranging the pile. I have found, however, that by constructing the platforms of freely turning rollers and locating these directly over and at a suitable short distance above the belt, all as described, it is possible to transfer such a lift of sheets from the platform to the moving belt without difficulty. When the pile has reached the desired height the operator gives it a slight pull in the direction of movement of the belt II, controlling the speed of movement as described. It roll freely over rollers 26 and when the end projects beyond the end of platform 25, it sags down until it contacts the moving belt as illustrated in Figure 3. The movement of the belt carries it onward until the last end drops onto the belt leaving the pile in substantially the same regular form in which it was built. It is then carried in the usual manner to the discharge end of the belt where it is discharged onto the smooth surface of the table 3|, from which it is slid, either mechanically or by hand, onto the smooth table of the trimming machine.

After being trimmed, and if necessary split, to the desired size, the finished sheets may be placed directly in the packing case in a usual manner, or transported on a belt or roller gravity type conveyor to a wrapping table or other desired destination.

Alternatively, if the paper is not to be trimmed or if the trimming is to be deferred, the table 3| can be provided with raising and lowering devices in a manner similar to tables 15, and the lifts can be delivered directly to skids or packing cases supported thereon, or the lifts of paper can be transferred from table 3! to one or more skids, packing cases or the like. In case more than one size of sheet or grade of paper is being delivered to table 3i, the lifts of each can be separated from the others, by the operaton either before or after trimming, and packed in cases, piled on skids, or otherwise suitably disposed of.

Defective sheets are slid to the left by the operator and deflected downward into the space between guides 49 and 50 which guide the sheet onto the moving belt M. These defective sheets are then delivered by belt 41 to the receiving table 45 at the discharge end of the conveyor where they may be stacked or otherwise disposed of by an operator, who, in case sheets of dififerent sizes are being sorted at one or more of the tables, may separate the different sizes into distinct piles if such separation is desired. They may, if desired, be further sorted and separated at this point into usable sheets or seconds, and unusable sheets or waste.

An alternative arrangement is illustrated in Figures 5, 6, and 7. In these figures the tables l5 with the lifting devices It, l1 and the recesses ii} in the floor are as previously described. The same is true of the conveyor H, carrier rolls i2, end rolls 13, the receiving platforms 25 with their rollers 26, framework 21 and guides 28 and 29, and of receiving table 3! and trimmer 32. For carrying away defective sheets, a conveyor 5| is provided, supported by carrier rolls 52 and passing around end rolls 53. For receiving the defective sheets, platforms 55 identical in construction with platforms 25, already described, are provided, together with guides 28 and 28 on platforms 25. At the discharge end of this conveyor is a receiving table 61 which may, if desired, be of the hydraulic type with piston 52, cylinder 63 and recess 6:2 in the floor.

As is apparent from Figure 5, the tables it with the piles 2! of paper to be sorted, and the sorters who stand to the left of the piles 2 i, as viewed in the figure, are located between the conveyor belts H and 5!, belt ii passing to the left and belt 5! to the right of the operator. In order that the paper can be trucked in to the tables l5 and the operators can have unimpeded access to their workplaces, I prefer to place the belts H and 5! at such height above the floor that ample head room remains below the lower run of the belt. In order to work at this height, the operator must stand at a considerable elevation above the floor. Platforms between the tables, made accessible by steps, can be provided for this purpose. I deem it generally better, however, to provide hydraulically or electrically operated platforms 65 which may be identical in all respects except size with the tables IS. The height of the platforms can then be adjusted individually to suit the stature and convenience of the sorters.

If it is desired to sort the defective sheets into usable sheets called seconds" and unusable sheets called waste in the original sorting operation, a third belt H carried on rollers 12 and iii may be provided in the device illustrated in Figures 5, 6, and 7, beneath belt in a manner analogous to that in which belt 41 is mounted beneath belt H in the arrangement illustrated in Figures 1, 2, and 4. The belt 1| may travel in either direction but is herein shown as travelling in a direction opposite to that of belts H and 5|. It may be arranged to discharge into any desired type of waste receptacle 75. Guides 19 and 8%! (Figure 7) are provided to carry sheets to belt ii when desired.

In the operation of these alternative devices, the sorters stand on platforms 65 and turn perfect sheets to the left onto belt H and imperfect sheets to the right onto belt 51. When lifts of suitable height have been built up they are pulled off onto the moving belts as described. If it is desired at one sorting to separate the paper into perfects, seconds" and Waste, only usable defective sheets are piled on the platforms 55. When lifts of the desired thickness are built up they are transferred to the conveyor belt 5| in the manner described in connection with Figure 3. These are delivered to table ti at the discharge end of the conveyor and may be disposed of as desired. If the seconds are to be trimmed at the same time, a trimming machine can be associated with table (it in a manner similar to that in which trimmer 32 is associated with table 3i. Sheets which are too defective for use are also slid by the sorter to the right but are diverted into the space between guides til and 80 and thus onto belt H which carries them to waste receiver 15.

In the present specification the sorters have heretofore been described as turning the sheets over one at a time, though it is customary in the art, when sorting some grades of paper, to turn two sheets over at a time. It will be apparent from the foregoing description, that the present invention is independent of whether one, two, or several sheets are turned over at a time. Accordingly, the term successively as used in the appended claims, is not to be understood as limiting the invention to uses where only a single sheet is turned over at a time.

The conveyor belts have been illustrated as horizontal but this is not necessary as they may travel at a moderate incline as is well understood. In this case the height h of the receiving platforms above the belt, as hereinbefore defined and limited, is to be measured at the discharge end of the platform, and the clearance c is to be measured where its value is the smallest.

The conveyors used have been described as belt conveyors since smooth surfaced endless belts are considered most desirable for the present purposes. By the term belt conveyor as used herein, however, I mean to include other types of conveyors, such as properly equipped platform and slat conveyors, which provide a suitably smooth working surface uninterrupted by openings of a width or form which would interfere with satisfactory support of the lifts of paper to be carried thereby.

.In place of hydraulically operated table lift- 8. ing and lowering devices, electrically or mechanically operated devices may be used if desired, as will be Well understood by those skilled in the art.

It can thus be seen that with the aid of the present invention it is possible to greatly expedite the handling of paper from the cutters through the sorting operation to the trimmers and packing for final shipment, to cut down the time, labor, and floor space required, to save waste, and otherwise improve the operation. It makes it possible to sort into three grades, in one operation, if desired, instead of the conventional two grades. It also has value in other operations than sorting in which paper must be handled sheet by sheet, or not more than a few sheets at a time, in one operation and, in lifts or piles of a large number of sheets in succeeding operations.

.I claim:

1. Method of transporting paper from a sorting operation in which sheets are handled successively, to a trimming operation in which sheets are handled in lifts, each containing a considerable number of sheets, which comprises: taking in succession sheets which have passed a given test in such a sorting operation, and stacking them into successive piles or lifts of the desired number of sheets and not exceeding about six inches in height; then when each pile is completed, gradually accelerating the pile in a horizontal direction so that it increasingly overhangs its support and bends downward due to gravity until it contacts and is reversely bent by, and is increasingly supported on until it is fully carried by, a surface moving in the direction of said initial acceleration; and transporting it on said moving surface to the location of the operation in which the sheets are handled in lifts.

2. Method of handling paper in sheet form for the purpose of inspecting successive sheets and delivering accepted sheets in piles or lifts to a trimming operation in which the sheets are handled in lifts, which comprises: taking sheets successively from a pile; successively inspecting said sheets; stacking those sheets which pass inspection into piles or lifts of the desired number of sheets and not exceeding about six inches in height; then, when each pile is completed, gradually accelerating the pile in a horizontal direction; permitting it to bend downward by gravity until it contacts and is reversely bent by, and is increasingly supported on until it is fully carried by, a surface moving in the direction of said initial acceleration; and transporting it on said moving surface to the location of the trimming operation in which the sheets are handled in lifts.

3. Method of handling paper in sheet form, in connection with a sorting operation, which comprises: inspecting and removing sheets successively from the top of a stack of sheets; disposing of the rejected sheets; forming the acceptable sheets into a pile; then, when the pile contains the desired number of sheets and is not over six inches in height, gradually accelerating the pile in a horizontal direction; permitting it to bend downward by gravity until it contacts and is reversely bent by, and is increasingly supported on until it is fully carried by, a surface moving in the direction of said initial acceleration; and transporting it on said moving surface to the location of the next stage in the handling process.

4. Method of handling paper in sheet form, in

connection with a sorting operation, which mprises: inspecting and removing sheets successively from the top of each of a plurality of piles, independently; disposing of rejected sheets from each of said piles; independently stacking accepted sheets from each pile into a succession of piles or lifts corresponding to the pile from Wh c the sheets were taken, the lifts of accepted sheets form all of said piles being formed in substantial alignment with each other; gradually accelerating each lift when it has been built up to contain the desired number of sheets and is not over about six inches in height, in a horizontal direction; permitting it to bend downward by gravity until it contacts and is reversely bent by, and is increasingly supported on until it is fully carried by a common moving surface, moving in the direction of said initial acceleration, under all of said plurality of aligned lifts; and transporting it on said moving surface, below any succeeding lifts in said aligned plurality of lifts, to the location of the next stage in the handling process.

5. Method of handling paper in sheet form, in connection with a sorting operation; which comprises: inspecting and removing sheets SuCceS- sively from the top of a stack of sheets; forming the acceptable sheets into a pile; then when the pile contains the desired number of sheets and is not over about six inches in height, gradually accelerating it in a horizontal direction; permitting it to bend downward by gravity until t contacts and is reversely bent by, and is increasingly supported on until it is fully carried by a surface moving beneath the bottom of said pile and in the direction of said initial. acceleration;

transporting it on said moving surface to the location of the next stage in the handling process; and diverting defective sheets and transporting them on a continuously moving surface to a place of disposal.

6. Method of handling paper in sheet form, in connection with a sorting operation; which comprises: inspecting and removing sheets successively from the top of a stack of sheets; forming the acceptable sheets into a pile; then, when the pile contains the desired number of sheets, gradually accelerating it in a horizontal direction; permitting it to bend in a downward direction by gravity until it contacts and is reversely bent by, and is increasingly supported on and finally carried by a surface moving beneath the bottom of said pile and in the direction of said initial acceleration; transporting it on said moving surface to the location of the next step in the handling process; transferring usable imperfect sheets onto a separate moving surface, transporting them on said surface to a destination distinct from that of the acceptable sheets; diverting unusable sheets onto a distinct moving surface; and transporting them thereon to a place of disposal.

7. In combination: a belt conveyor for transporting paper in sheet form; a plurality of tables, adjacent to the belt, for supporting an equal number of stacks of paper; a like number of paper-receiving platforms, each located a short distance above the belt and adjacent one of said tables, and each comprising a series of Substantially parallel, freely rotating rollers, mounted with their axes transverse to the direction of travel of the belt; a receiving table at the discharge end of said conveyor; a plane papersupporting surface so related to said receiving table that the one constitutes, in effect, a coplanar extension of the other, so that lifts of paper delivered by said conveyor to said receiving table can be slid directly into position for an operation wherein said lifts are handled as units.

8. In combination with an operation in which sheets of paper are handled individually, the method of delivering sheets in piles from such operation to another location, which comprises: forming the sheets into a pile or lift as they come from said operation; supporting said pile or lift in a fixed position at a height not greater than one-sixth the length of the sheets above a moving belt; then, when the pile or lift has reached the desired thickness, imparting thereto a gradually accelerated movement, in the direction of belt travel, carrying the forward end of the pile'progressively farther beyond the place of support, whereby the forward end sags by gravity until it rests on and assumes the velocity of said belt while the portion of the pile carried by the belt progressively increases and that supported above the belt progressively decreases until the entire pile has moved beyond said place of support and is carried by the moving belt for delivery at the desired location.

9. Method of transferring a stationary preformed pile of paper sheets onto a moving conveyor belt, which comprises: supporting the pile for free movement in the direction of belt travel, in a substantially horizontal position, and at a height above said belt not exceeding one-sixth of the length, in the direction of belt movement, of the sheets forming said pile; imparting to the pile a gradually accelerated movement, in the direction of belt travel, carrying the forward end of said pile progressively farther beyond the place of support whereby the forward end sags by gravity until it rests on and assumes the velocity of said belt, while the portion of the pile carried on the belt progressively increases and that supported above the belt progressively decreases until the entire pile has moved beyond the place of support and is carried by the moving belt.

10. Method of claim 9 wherein the direction of movement of the supported rearward end of the pile is approximately parallel to that of the forward end of the pile carried on the belt, and the pile after transfer to the belt retains substantially the same form as prior to such transfer.

11. Apparatus for use in sorting paper sheets, stacking the sorted sheets into piles or lifts, and transporting the piles or lifts of sorted sheets to another location, which comprises: an endless conveyor belt; a plurality of vertically adjustable tables each adapted to support a pile of sheets to be sorted and adjust the top of the pile to working height as required, said tables being located adjacent to, and spaced at working intervals along, the side of said conveyor belt; a like number of platforms for receiving sorted sheets, each platform comprising a plurality of parallel rollers rotatable on axes transverse to the direction of travel of said belt, and each located over said belt and adjacent one of said tables, the upper surface of each of said platforms being not more than ten inches above the surface of said conveyor belt, and not less than three inches of clearance being left between the structure of said platforms and the surface of said conveyor belt.

12. The apparatus of claim 11 wherein a receiving table is placed at the discharge end of said belt conveyor for receiving the piles or lifts of sorted sheets at a location where the paper is to be handled in such piles or lifts.

13. Apparatus for use in sorting paper sheets,

stackin the sorted sheets into piles or lifts,

\ transporting the piles or lifts of sorted sheets to another location, and transporting rejected sheets to a separate location, which comprises: an endless conveyor belt; a plurality of vertically adjustable tables each adapted to support a pile of sheets to be sorted and adjust the top of the pile to working height as required, said tables be- .ing located adjacent to, and spaced at intervals along the side of, said conveyor belt; a like number of platforms for receiving sorted sheets, each platform comprising a plurality of parallel rollers rotatable on axes transverse to the direction of travel of said belt, and each located over said belt and adjacent one of said tables, the upper surface of each of said platforms being not more than ten inches above the surface of said conveyor belt, at least three inches of clearance being left between the structure of said platforms and the surface of said conveyor belt; a waste conveying belt located below said belt conveyor and discharging at a separate location, for carrying away sheets rejected in the sorting operation; and guide means for guiding rejected sheets onto said waste conveying belt.

14. Apparatus for facilitating the sorting paper sheets into perfects, seconds, and waste, stacking the perfects and seconds into piles or lifts, transporting the piles or lifts of perfects and of seconds to distinct locations, and transporting waste sheets to a different location, which comprises: two endless conveyor belts disposed in parallel relationship; a plurality of vertically adjustable tables each adapted to support a pile of sheets to be sorted and adjust the top of the pile to working height as required, said tables being located between said two conveyor belts and immediate adiacent one side of each, and spaced at intervals along the length of said belts; a like number of platforms located over each of said belts and adjacent opposite sides of said tables, one for receiving perfect sheets and one for receiving seconds from the sorting operation, each of said platforms comprising a plurality of parallel rollers rotatable on axes transverse to the direction of travel of the belt therebelow, the upper surface of each of said platforms being not more than ten inches above the surface of the corresponding belt, and at least three inches clearance being left between the structure of said platforms and the surface of the belt; a waste conveying belt located below one of said conveyor belts and discharging at a different location; and means for guiding rejected sheets onto said Waste conveying belt.

HERBERT T. RANDALL.

References Cit-ed in the file of this patent UNITED STATES PATENTS Number Name Date 863,590 Cowley Aug. 20, 1907 872,457 Russel Dec. 3, 1907 1,319,190 Van Houten Oct. 21, 1919 1,492,178 Nicholas Apr. 29, 1924 1,563,747 Hosmer Dec. 1, 1925 1,648,531 Bayley Nov. 8, 1927 1,669,497 Steegmuller May 25, 1928 1,710,969 Dempsey Apr. 30, 1929 1,847,264 Sandberg Mar. 1, 1932 1,861,963 Jennings et al June 7, 1932 1,959,735 Phillips May 22, 1934 2,108,869 Sandzneyer Feb. 22, 1938 2,109,050 Quick et al. Feb. 22, 1938 2,228,887 Peterson Jan. 14, 1941 2,392,032 Domville, Jr., et al. Jan. 1, 1946 2,497,149 Berdis et al. Feb. 14, 1950

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