US2819077A - Sheet feeding device - Google Patents

Description

Jan. 7, 1958 H. J. 6055 SHEET FEEDING DEVICE Filed July 13, 1953 INVENTOR. HAROLD J. GOSS ATTORNEYS United States sneer FEEDING DEVICE Harold J. Goss, Nashua, N. H., assignor to The International Paper Hex Machine Company, Nashua, N. iii, a corporation of New Hampshire Application July 13, 1953, Serial No. 367,438

Claims. (Cl. 271-35) This invention relates to a sheet feeder and carrier unit for individually and successively feeding each endmost sheet from a stack of flat sheets of uniform thickness and carrying the sheet away from the stack. It relates especially to top feeding magazine used in paper box folding machines for holding a stack of box blanks prior to their passage along the paper line of the machine to be formed into a box.

It has heretofore been proposed to use as an envelope feeder in postage cancelling machines a power operated wheel or pulley having an elongated projection on its circumference and having a flexible belt around its periphery, the belt contacting the surface of the endmo-st envelope of the stack each time the projection passes thereunder. However, such belt feeding mechanisms have usually been used together with a non revoluble, yieldingly mounted barrier, gate or separator element normally in the path of advance of the endmost envelope or envelopes and required to be raised out of the path to permit the passage of a single endmost envelope. Thus when the circumferential projection on the feed pulley lifts the belt into friction engagement with the endmost envelope, the envelope is advanced under the yielding separator which rises sufficiently to permit passage of one envelope but forms a barrier to the next succeeding envelope. Usually such yielding separators have been mounted on comparatively slow speed machines wherein the possibility of too much yielding is not a factor and the drag caused by the nonrevoluble separator is not important.

This invention, however, is intended for use on high speed machines for identical flat sheets wherein it is essential that no double or triple feeds occur, essential that unnecessary frictional drag on the sheets be eliminated and essential that wear on the friction elements be not sufiicient to cause frequent maladjustment of the moving parts.

It is the principal object of this invention to combine with such belt feeding means, a separator means which is non yieldable and forms a passage of exactly the height of a single sheet thus positively assuring a feed of only one sheet at a time.

Another object of the invention is to provide a non yielding sheet separator in which at least one of the passage forming elements is freely revoluble in the direction of feeding, thus tending to prevent any drag or retarding effect on a sheet moved through the passage.

Still another object of the invention is to provide means for retaining and guiding each sheet from where its lead ing edge exits from the passage up to any desired location away from the stack, thus avoiding any gaps to be jumped or crossed by the sheets.

A further object of the invention is to provide a sheet feeder and sheet carrier as a single unit, said unit including a single tension pulley for both the feeder and carrier and including a pair of smooth surfaced, nonyielding separator rolls which can be easily adjusted transversely for various widths of sheets.

A still further object of the invention is to provide belt feeder means, belt carrier means and nonyielding separator means in which a resilient spring at the passage of the separator means urges the leading edge of each sheet into the space between the belts of said feeder and carrier means.

In the drawing,

Fig. 1 is a plan view of a preferred embodiment of the invention applied to the top feeding magazine of a paper box folding machine with parts broken away for clarity.

Fig. 2 is a side elevation of the device shown in Fig. l, and

Fig. 3 is a fragmentary plan view of the fixed non yielding gauges and the resilient spring of the invention mounted on the lower front edge of the top feeding magazine.

As shown in the drawing M is the top feeding magazine of a paper box folding machine, such as is well known in the art. The magazine M has an inclined bottom 20, side walls or guides such as 21 and a lower front or forward edge 22, and is attached in any suitable manner to the frame K of the paper box folding machine. A plurality of identical sheets such as 0, each of uniform thickness, are fanned out in magazine M to form a stack N and, in the case of a paper box folding machine, each sheet 0 is a box blank. The endmost sheet or blank 0 in stack N is designated by the numeral 23 and inclines upwardly and rearwardly from its leading edge 42 at or near the lower front edge 22 of magazine M.

The paper line of the box folding machine is indicated at P and sheet conveyor mechanism L is indicated for advancing each sheet such as O individually and successively along the paper line P. The sheet conveyor mecha nism L is well known in the art and includes an endless chain 2'7 trained around sprockets such as 28 and provided with a plurality of spaced upstanding lugs 29 each lug arranged to engage the trailing edge of a sheet 0 and advance the same along paper line P. A shaft 26 is pro vided for the sprockets such as 28 and there is usually a considerable gap between the lower forward edge 22 of magazine M and the lugs 29 of conveyor mechanism L.

The sheet feeder and carrier unit of this invention includes nonyielding sheet separator means A, a flexible friction feeder belt B and sheet feeder means C.

The nonyielding sheet separator means A includesa nonyielding gauge such as 30 and preferably a pair of such gauges 30 and 31, each of rigid material such as bar metal and each positioned on an opposite side of the central longitudinal axis of magazine M along the lower forward edge 22 of the bottom thereof. Each gauge such as is of L shape, one arm 32 of the gauge having a hole 33 encircling a bolt 34 threaded in a fixed block or bar 36. A coil spring 37 is positioned between the bar 36 and the arm 32 whereby the gauge 30 is fixed in position but may be moved to other positions by rotating the head 38 of bolt 34. The other arm 39 of gauge 30 extends upwardly and terminates in a tip 40, beveled at 41 and located in the path of the leading edge 42 of the endmost sheet 23 of stack N.

Also included in sheet separator means A is a nonyi-elding roll such as 43 and preferably a pair of such rolls t3 and 44, each of rigid material such as metal and each nonyieldingly mounted to freely revolve around a shaft 45 which extends transversely above the pair of gauges 3i) and 31. Each roll such as .43 or 44 has a smooth, antifriction circumferential surface 47 or $8 and the surface of each roll is spaced the thickness of a single sheet from the tip of one of the pair of gauges 3t and 31. A nonyielding passage 5%) is thus formed between the surfaces 47 and 48 and the tips iii of gauges 3d and 31 the height of the passage being adjustable to accommodate various thicknesses of sheets by means of bolts such as 34. As indicated in Fig. 2, the leading edge 42 of each endmost sheet 23 rests against the beveled portions 41 of gauges 30 and 31 just in front of the passage 50, and while the rolls 43 and 44 are in tangential contact with the exposed surface 51 of sheet 23, they have no tendency to urge the same through passage 50 in view of their antifriction surfaces 47 and 48. The freely revoluble smooth surfaced rolls 43 and 44 thus serve as the forward wall of the magazine M as well as forming one side of the nonyielding sheet passage 50.

The sheet feeder means C of the invention comprises a feeder pulley, or wheel 60 mounted to rotate with the shaft 45 and having an elongated circumferentially extending projection, or bump 61 on its periphery. The projection 61 is provided With a gradually tapered leadmg edge portion 62 and a gradually tapered trailing edge portion 63 which edge portions merge with the circumferential surface 64 of feeder pulley 60. Shaft 45 is connected by suitable chains or belts not shown and well known in the art, to shaft 26 whereby it is power driven at high speed in synchronization with the sheet conveyor mechanism L.

A flexible friction feeder belt B is trained around the feeder pulley 60 and extends rearwardly in the direction of feeding to a pulley 66 carried by a transversely extending shaft 67. The upper stretch 68 of feeder belt B is inclined while the lower stretch 69 of belt B is substantially horizontal to extend in prolongation of the paper line P, In the position shown in Figs. 1 and 2, the diameter of the circumferential surface 64 of feed pulley 60 plus the thickness of feeder belt B is less than the diameter of the circumferential surfaces 47 and 48 of the rolls 43 and 44, whereby the friction surface 70 of belt B does not touch the exposed surface 51 of endmost sheet 23 at it is moved past the same by pulley 60. I- Iowever, when the circumferentially extending projectlon 61 of feeder pulley 60 is rotated into contact with the undersurface 71 of belt B by shaft 45, the belt B is raised so that the diameter of the pulley 60, plus the thickness of projection 61 and the thickness of belt B is greater than the diameter of the rolls 43 and 44. Thus the friction surface 70 of belt B engages the exposed surface 51 of endmost sheet 23 and slides the leading edge 42 thereof into and beyond the passage 50 formed by the nonyielding separator means A. The momentum achieved by the endmost sheet 23 from belt B and feeder means C, together with the effect of further contact with the lower stretch 69 of belt B tends to carry the sheet 23 up to the position required for engagement in sheet conveyor mechanism L.

However, I prefer to provide an endless carrier belt D to firmly hold each sheet against the lower stretch 69 of belt B as it travels across the gap or space between passage 50 and conveyor mechanism L. Carrier belt D is positioned below and opposite to belt B and is trained around a pulley 80 carried by shaft 26 and around a pulley 81 carried by a shaft 82. Preferably, pulley 81 is located directly under feeder pulley 60 with its shaft 82 extending below and parallel to shaft 45 transversely of the machine. Pulley 81 is thus positioned just beyond the passage 50 and close to the fixed gauges 3t} and 31. The lower stretch 85 of belt D is inclined while the upper stretch 86 is substantially horizontal in prolongation of paper line P and in juxtaposition with the lower stretch 69 of belt B. Each sheet 0 is received in the space between stretches 69 and 86 and firmly held therebetween until it is delivered to sheet conveyor mechanism L.

I also prefer to provide a resilient leaf spring E at the forward edge 22 of magazine M and having one end 90 thereof fixed to a block 35 by bolts 91, 92, block 35 being slidably attached to bar 36 by bolt 97 in slot 98. The spring E is bent at right angles at 93 and its free end 94 extends in the direction of feeding, in the plane of passage 50, to a point beyond passage 50, proximate the 4 nip of belts B and D. As the exposed surface 51 of each endmost sheet 23 is engaged and slidably advanced by feeder belt B, the leading edge 42 thereof slides along the straight upper surface 96 of leaf spring E and the leading edge portion 42 of each sheet 23 is urged to follow a curved path conforming to the curvature of the belt B rather than to travel in a straight line in extension of the flat plane of the endmost sheet in the stack. Thus the leading edge 42 is resiliently urged in a curved path into the space between the stretches 69 and 86 of belts B and D and possibilities of malfunction are avoided. It should be noted that the upper surface 96 of spring E extends in a straight line substantially tangential to the pulley 66), at passage 50, both in front and in rear of the passage thus permitting each sheet to slide easily therealong.

Preferably also, a tension pulley or roll F is provided carried on the end of an arm 100, the opposite end of the arm being split at 101 and having a bolt 102 by which the arm may be tightened on shaft 67 under various clamping pressures as desired. Tension pulley F is so positioned that it bears upon the lower stretch 69 of feeder belt B and at the same time exerts tension on the upper stretch 86 of belt D.

In installing the feeder and carrier unit of this invention on box folding machines havingtop feeding magazines, the transverse shaft 26 of the existing conveyor mechanism is preferably utilized. The transverse shafts 45, 67 and 82 are added in the positions indicated in the drawing and pulleys 60, 81, 66 and 80 aligned preferably along the longitudinal centre line of the machine on their respective shafts. Belts B and D are then installed as are the nonyielding rolls 43 and 44. Gauges 30 and 31 are mounted opposite rolls 43 and 44 and adjusted to the proper height to form a passage 50 for the particular type of sheets or blanks to be used. In opera tion the freely revolving rolls 43 and 44 and gauges 30 and 31 maintain the non-yielding passage 50 while projection 61 raises belt B with each revolution of feeder pulley to slide the endmost sheets, such as 23, individually and successively through passage 50' Tension pulley F maintains belts B and D at the proper tension while each sheet such as O is carried across the gap between passage 50 and conveyor mechanism L. Spring E continually urges the forward portion of each successive sheet into the nip of the belts B and D during the operation of the unit.

At least one nonyielding sheet separator means A comprising a roll such as 43 and a fixed gauge such as 30 and at least one flexible friction feeder belt B and sheet feeder means C are essential to the operation of the invention. Instead of positioning the belt B and roll 60 between two sheet separator means A as shown in the drawing, a single sheet separator means A may be positioned between a pair of belts such as B and rolls such as 60, if desired.

I claim:

1. Apparatus for individually and successively sliding each endmost sheet from the end of a stack of sheets of uniform thickness, said apparatus comprising nonyielding sheet separator means including a freely revoluble roll having a smooth antifriction circumferential surface in engagement with the exposed surface of each endmost sheet and forming one side of a nonyielding sheet passage equal in height to the thickness of a sheet and located along the leading edge of an endmost sheet in the stack; a flexible friction feeder belt having a stretch advancing continuously from proximate the exposed surface of an end sheet in said stack along the plane of said passage and up to a sheet conveyor mechanism; sheet feeder means comprising a feeder pulley of less radius than, and rotating co-axially with, said roll, said pulley normally supporting said belt stretch out of contact with each endmost sheet but having an elongated circumferential projection with gradually tapered leading and trailing edges for periodically moving said feeder belt outwardly, radially beyond the periphery of said roll into frictional engagement with the exposed surface of an end sheet of said stack and sliding said sheet through said passage.

2. A combination as specified in claim 1 wherein said nonyielding sheet separator means comprises said antifriction surfaced, freely, revoluble, roll and a fixed gauge opposite to, and spaced the thickness of a single sheet from, the surface of said roll for forming the other side of said nonyielding sheet passage and for forming a stop for the leading edge of each endmost sheet in said stack.

3. A combination as specified in claim 1 wherein said nonyielding sheet separator means comprises a pair of laterally spaced apart gauges fixed below the path of the leading edge of said endmost sheet and a pair of laterally spaced apart freely revoluble, smooth surfaced nonyielding rolls, each having a portion of its smooth surface in contact with an endmost sheet and another portion of its smooth surface spaced the thickness of a single sheet above one of said fixed gauges, and said feeder pulley is mounted between said rolls and co-axially therewith.

4. A combination as specified in claim 1 wherein said sheet separator means includes rigid, stationary, stop means fixed in the path of the lower leading edge of the endmost sheet of the stack at the passage of said sheet separator means.

5. A combination as specified in claim 1 plus a resilient leaf spring, fixed proximate the passage of said sheet separator means, said spring having a straight, smooth surfaced free end extending substantially tangential to the surface of said feeder pulley at a point beyond said passage in the direction of feeding and positioned to urge the leading edge of each endmost sheet into a curved path conforming to the curve of the circumference of said feeder pulley.

6. A combination as specified in claim 1 plus an endless carrier belt having a straight stretch continuously advancing in juxtaposition with and at the same speed as said stretch of said feeder belt, and having a partly circular stretch advancing in the direction of feeding just beyond said passage and in the path of an endmost sheet emerging from said passage.

7. A combination as specified in claim 6 plus a tension pulley, mounted between said passage and said conveyor mechanism, in contact with the undersurface of the stretch of said feeder belt that is in juxtaposition with said straight stretch of said carrier belt for simultaneously keeping both said stretches under tension.

8. A feeder and carrier unit for individually and successively sliding each endmost sheet from the end of a stack of sheets of uniform thickness, said unit comprising the combination of nonyielding sheet separator means including a smooth surfaced, freely revoluble roll engaging said stack and cooperable with a fixed gauge for forming a nonyielding sheet passage, equal in height to the thickness of one said sheet, adjacent the leading edge of said endmost sheet; an endless friction feeder belt continuously advancing adjacent said passage and spaced from the exposed surface of said endmost sheet; a feeder pulley co-axial with said roll and supporting said belt, said pulley having a circumferential projection adapted to periodically move the adjacent portion of said belt outwardly, radially beyond the periphery of said roll into a position of engagement with the exposed surface of each endmost sheet until said belt has moved the leading portion thereof through said passage; and a carrier belt, cooperable with said feeder belt for receiving each sheet advanced through said passage and firmly holding the same against the feeder belt while travelling away from said stack.

9. A combination as specified in claim 8 plus resilient spring means and operable beyond said passage proximate said sheet separator means for urging the leading edge portion of each endmost sheet, advanced through said passage, into the space between said feeder belt and said carrier belt.

10. A feeder and carrier unit for individually and successively sliding each topmost sheet from a stack of identical sheets in the top feed magazine of a paper box machine, said unit comprising a pair of nonyielding gauges spaced apart on opposite sides of the lower front edge of said magazine; a pair of smooth surfaced rolls, nonyieldingly mounted on a shaft extending transversely above said gauges to freely revolve in the direction of feeding with the smooth surfaces thereof in contact with each topmost sheet, said rolls being spaced apart on said shaft and each positioned opposite one of said gauges to form a nonyielding passage therehetween, equal in height to the thickness of a single sheet; a feeder pulley positioned between said pair of rolls and mounted to co-axially revolve with said shaft independently of said rolls in the direction of feeding, said pulley having an elongated circumferentially extending projection thereon; an endless feeder belt trained around said feeder pulley and extending in the direction of feeding, said feeder belt being adapted to engage and slide each endmost sheet into said passage with each revolution of the projection on said feeder pulley; an endless carrier belt extending in the direction of feeding below, and opposite to, said feeder belt and arranged to firmly hold each sheet advanced through said passage against said feeder belt as said sheet is carried away from said passage and a resilient leaf spring, positioned between said pair of nonyielding gauges and having its free end extending beyond said passage, said free end being normally out of contact with an endmost sheet but moved radially out- Ward beyond the periphery of said rolls to urge the leading edge portion of each endmost sheet into the space between said feeder belt and said carrier belt.

References Cited in the file of this patent UNITED STATES PATENTS 1,380,483 La Bombard June 7, 1921 1,399,288 Bowes Dec. 6, 1921 1,626,386 Bronander Apr. 26, 1927 1,955,066 Hiller Apr. 17, 1934 1,956,229 Sidebotham Apr. 24, 1934 2,080,968 Krell May 18, 1937 2,339,835 Burkhardt Ian. 25, 1944

Images