US3192807A

US3192807A - Sheet control system for paper cutters

Info

Publication number: US3192807A
Application number: US252950A
Authority: US
Inventors: William J Haselow; William E Aschenbrenner
Original assignee: Consolidated Papers Inc
Current assignee: NewPage Wisconsin System Inc
Priority date: 1963-01-21
Filing date: 1963-01-21
Publication date: 1965-07-06
Anticipated expiration: 1982-07-06
Also published as: GB1071025A; DE1461203A1; CH435964A

Description

y 1965 w. J. HASELOW ETAL 3,

SHEET CONTROL SYSTEM FOR PAPER CUTTERS Filed Jan. 21, 1963 INVENTORS:

United States Patent '0 Sunni" CONTROL srsrnM FOR PAPER omens William J. Haseiow and Wiliiain E. Aschenbrenner,

Wisconsin Rapids, Wis., assignors to Consolidated Papers, -Inc., Wisconsin Rapids, Wis., a corporation of Wisconsin Filed Jan. 21, 1963, Ser. No. 252,950 7 .-Claims. (Cl. 83-24) The present invention relates .to apparatus for cutting continuous webs of paper into sheets, and more particclarly, to an apparatusfor controlling the movement of a sheet of paperonce-it is severed from the web.

Heretofore, sheets of paper cut from a continuous paper web by means of a rotary cutter had a tendency .to whip with the result that the trailing edges of the sheets were frequently crumpled due to secondary impact by the cutter, corners were often turned and some of the sheets were folded, thereby creating difficulties in cutter operation and causing jamming as the-sheets were fed .to the layboy. Particular ditliculty has been experienced when using ;an automatic sheet sampler in conjunction with the rotary cutter. To minimize the .difliculties it has been necessary to limit the cutter operatingspeed.

.A principal object of the invention is to provide apparatus for controlling the movement .of sheets of paper and the like immediately after severing from the web so that they will not be damaged and may be transported away from the cutter insuch manner as to be efficiently and effectively assembled :or stacked.

Another .object ,of "the .invention is to provide appara- :tus for controlling the movement of sheets of paper and thelike that have .been severed from a continuous .web by meansof a rotary cutter by counteracting the forcesztending to cause the severed sheets to whip. In particular,

it is anobjectof the invention to counteract the affect on the severed sheets of the low pressure areas at the-periphery ,of the rotary cutter which are created its rotation.

A further object of the invention is the provision of apparatus ,of the character described whichis efiicient and effective in use, which may be adjusted forlefficient use with paper sheets of different widths, and which facilitates greatly increased cutter operating speeds.

v,(Zither objects and advantages of the invention will become apparent in the following detailed description.

Now, in order'to acquaint those skilled in the art with the mannerofmakingand using our sheet control system, we shall describe, in connection wit-h the accompanying drawings, the preferred embodiment of our invention and the preferred manner of making and using the same.

In the drawings:

FIGURE 1 is a diagrammatic view, in side elevation, of a paper cutting and sheet feeding machine embodying the apparatus of the present invention;

FIGURE 2 is a fragmentary perspective view of a combined paper cutting and feeding machine embodying the sheet control apparatus ,of the invention;

FIGURE 3 is a fragmentary plan view of sheet control apparatus made in accordance with the invention; and

FIGURE 4 :is a vertical sectional view taken substantially on line 44 of FIGURE 3. I

Referring now to the drawings, and particularly to FIGURE 1, the combined sheet cutting and feeding machine embodying the present invention includes a feed roll 12 and a cooperating roll 14 between which is fed, by rotation of the roll 12 in the direction of the arrow, a web 16 of sheet material such as paper or the like. The web 16 is fed angularly downwardly on a doctor board 18 to be severed by means of a cutting assembly 20. The cutting assembly 20 includes a suitably driven ice cutting roll 22 having a radially outwardly extending blade 24 which cooperates with a bed knife 26 to sever the web l6 into a plurality of individual sheets of equal length. .Once severed from the web, the sheets are directed to a transport tape conveyor 28 by means of an inclined guide tape conveyor 30 whose tapes 32 move in the direction of the arrow in FIGURE 1 and are disposed between tapes 34 of the tape conveyor 28, as shown best in FIG- URE 2. Cooperating with the tape conveyor 30 is a guide tape conveyor 36 having a plurality of tapes 38 (only one of which is shown) which cooperate with the tapes 34 of the conveyor 23 in feeding the severed sheets to the right, as viewed in FIGURE 1, after the sheets leave the inclined tapes 32.

Generally, the

tape conveyors

28, 30 and 36 are operated at a lineal speed greater than the lineal speed of web feed so as to pull the web taut to facilitate cutting and then to expedite the cut sheet away from and out of the path of movement of the cutter 24. Despite the intended purpose of the high speed tapes, the sheets due to whipping are frequently damaged-or folded by the cutter re-striking the trailing edge of the sheets.

Accordingto thepresent invention, means are provided for eliminating whipping and for assuring effective content of the severed sheets withthe tapes 32 so that the severed sheets are fed rapidly and in flat condition to the bight of thetapes 38 and without being re-struck by the cutter. To this end, we provide vacuum apparatus .40 including a suction box .42 divided by partitions 44 into a plurality of suction chambers 46. Each of the suction chambers 46 is connected by conduit means .48 to a vacuum header 5!) which in turn is connected to arsuitable vacuum source by meansof a pipe52.

A plurality of1valvesr54 control vacuum communication between the severalchambers 46 and headerfitl. By this arrangement one or more of the chambers46 may be cut oif from the vacuum source in the event that the width of the severed sheets is less than the-length of the suction box 42. Each conduit 48 preferably, includes a :flexible section facilitating assemblyand disassembly of the described components and serving as a vibration dampener between :the suction box andthe vacuumheader and supply means. The suction box 42 is illustrated as being vsemi-circular in cross-section and is provided with a flat :cover plate :56 having a plurality of openings 58. The box 42 is disposed atright angles to the conveyor tapes with the face or cover plate '56 thereof substantially in contact with-the lower surfaces of the upper run of the tapes 3 2.

It will be appreciated that a low pressure zone is created at the periphery of the cutter roll 22 because of the cooperating elements 24 and '26 of the cutting assembly .29. This low pressure are-a tends to induce the leading edge of the severed sheets to rise. As a result, the sheets :tend to whip and do not come-to rest on the tapes 32, and the high speed tapes therefore fail to accomplish theirintende'd purpose. By use of the vacuum apparatus of .the present invention, each severed sheet'is induced to come immediately'into flush engagement with the tapes 32 and thereby to pass into the bight of the tapes 38 and 34 flat condition without being re-struck by the cutter blade 24. t V

The sheet control apparatus of the present invent-ion exhibits characteristics of great advantage in efficient-cutting and feeding of severed sheet material. By use of the apparatus whipping of the sheets has been eliminated, thereby eliminating turned corners and folded sheet defects. In actual operation, the present invention has produced the result of increasing cutter operating speeds from an average of 290 feet per minute to 420 feet per minute, and has at the same time mitigated folded sheets and jamming of and shut-down time on the cutters. Thus, the objects and advantages of the invention have been shown herein to be attained in a convenient, economical and practical manner.

While we have shown and described what we regard to be the preferred embodiment of our invention, it will be appreciated that various changes, rearrangements and modifications may be made the-rein without departing from the scope of the invention, as defined by the appended claims.

We claim:

1. Apparatus for conveying sheets of material away from a rotary cutter comprising conveyor means arranged to receive sheets from the cutter, means for biasing the said sheets toward said conveyor means, said biasing means comprising a suction assembly including an elongated suction box mounted beneath said conveyor means transversely of tr c direction of sheet movement, said box having a plurality of partitions therein spaced apart transversely of the dir ection'of sheet movement dividing the interior thereof into a plurality of suction chambers, conduit means communicatively connecting each of said chambers to a vacuum source, and valve means in each of said conduit means.

2. A combined cutting and handling apparatus for sheet material for cutting a continuous web of sheet material into sheets of predetermined length comprising a rotating cutter roll, a cutting assembly including a bed knife and a cooperating knife on the periphery of said roll, feed rolls for moving the web to said cutting assembly, a conveyor extending adjacent and below said cutting assembly for transporting sheets away from said cutting assembly, and means mounted in operative relation to said conveyor for preventing the leading edge of each sheet from whipping, said means comprising an elongate vacuum box extending transversely of and abutted against the under surface of said conveyor adjacent but downtransport conveyor for moving severed sheets away from the cutter assembly, said transport conveyor having a plurality of spaced tapes, a pair of guide tape conveyors for directing the severed sheets to the upper surface of the tapes of said transport conveyor, one of said guide conveyors being angularly disposed with respect to said transport conveyor and having a plurality of spaced tapes interleaved with the tapes of said transport conveyor, the other of said guide conveyors being operable to urge the leading edge of each severed sheet into engagement with the tapes of said transport conveyor, said conveyors being operated at a greater lineal speed than said feed rolls, the improvement comprising means for assuring initial contact of the leading edge of each of the severed sheets with the tapes of said one guide conveyor, said means comprising a vacuum assembly including .an elongated suction box disposed in abutment with the under surfaces of the tapes of said first guide conveyor, said suction box being communicatively connected to :a .vacuum source.

4. In combined cutting and handling apparatus as set forth in claim 3, said suction box being divided into a plurality of individual suction chambers, a vacuum manifold communicatively connected to a vacuum source, conduit means connecting each of said chambers to said manifold, and valve means in each of said conduit means for selectively controlling the evacuation .of each of said chambers.

5. Combined web cutting and sheet handling apparatus for cutting a continuous web of sheet material into individual sheets, comprising a rotating cutter roll, a web cutting assembly including a knife on the periphery of said roll and a co-operating knife, feed rolls for moving the web to said cutting assembly, conveyor means extending adjacent but below said cutting assembly for transporting sheets cut from the web away from said cutting assembly, and means mounted in operative relation to said conveyor means adjacent but downstream from said cutting assembly for mitigating whipping of the leading edge of each sheet and for causing the leading edge and the progressively following portions of each sheet to engage said conveyor means.

6. Combined web cutting and sheet handling apparatus for cutting a continuous web of sheet material in individual sheets, comprising a rotating cutter roll, a web cutting assembly including a knife on the periphery of said roll and a co-operating knife, feedrolls for moving the web to said cutting assembly, conveyor means extending adjacent but below said cutting assembly for transporting sheets cut from the web away from said cutting assembly, said conveyor means being operated at a greater lineal speed than said feed rolls, and means extending transverse-.

ly of said conveyor means in co-operative relation there- 'with adjacent but downstream from said cutting assembly for creating a pressure differential between the opposite sides of each sheet with the greater pressure acting do-Wnwardly on the upper side of the sheet, said means being positioned to create said pressure differential over the full length of each sheet as the sheet passes said means for pressing the leading edge and the progressively following portions of each sheet into engagement with said conveyor means and thereby mitigating whipping of the leading edge.

7. A process of handling a continuously moving web of flexible sheet material and sheets cut therefrom by cutting means operating intermittently on the continuously moving web to eliminate bent corners and fold defects in the sheets consequent upon cutting, comprising the steps of applying to the leading end portions of the web at a point adjacent but downstream from the cutting means a conveying force of greater speed than the speed of web movement, physically pressing the leading end and progressively following portions of the web against the conveying means prior to and during cutting of the web, and

v physically pressing the progressively following portions and the trailing edge of the sheet cut from the web away from the cutting means and against said conveying means.

References Cited by the Examiner UNITED STATES PATENTS 7 705,041 7/02 Copland 83-100 2,324,950 7/43 Pratt 83-400 2,546,221 3/51 Funk 83-400 X 2,615,518 10/52 Hornbostel 83-24 X 2,796,128 6/57 Denck 83-24 2,865,449 12/58 Frankenburg 83-100 2,976,751 3/61 Duba 83-2'4 WILLIAM W. DYER, JR., Primary Examiner.

HUNTER C. BOURNE, JR., ANDREW R. JUHASZ, Examiners.

Claims

1. APPARATUS FOR CONVEYING SHEETS OF MATERIAL AWAY FROM A ROTARY CUTTER COMPRISING CONVEYOR MEANS ARRANGED TO RECEIVE SHEETS FROM THE CUTTER, MEANS FOR BIASING THE SAID SHEETS TOWARD SAID CONVEYOR MEANS, SAID BIASING MEANS COMPRISING SUCTION ASSEMBLY INCLUDING AN ELONGATED SUCTION BOX MOUNTED BENEATH SAID CONVEYOR MEANS TRANSVERSELY OF THE DIRECTION OF SHEET MOVEMENT, SAID BOX HAVING A PLURALITY OF PARTITIONS THEREIN SPACED APART TRANSVERSELY OF THE DIRECTION OF SHEET MOVEMENT DIVIDING THE INTERIOR THEREOF INTO A PLURALITY OF SUCTION CHAMBERS, CONDUIT MEANS COMMUNICATIVELY CONNECTING EACH OF SAID CHAMBERS TO A VACUUM SOURCE, AND VALVE MEANS IN EACH OF SAID CONDUIT MEANS.