US2561097A

US2561097A - Sheet delivery control for cutoff mechanisms

Info

Publication number: US2561097A
Application number: US708501A
Authority: US
Inventors: William H Cleaver
Original assignee: Samuel M Langston Co
Current assignee: Samuel M Langston Co
Priority date: 1946-11-08
Filing date: 1946-11-08
Publication date: 1951-07-17
Anticipated expiration: 1968-07-17

Description

July 17, 1951 w. H. CLEAVER ,9

SHEET DELIVERY CONTROL FOR CUTOFF MECHANISMS Filed Nov. 8, 1946 2 Sheets-Sheet l ENVENTCJR or} K) Wilkiumfi'. Ghana] 5 p I 'gg wg W. H. CLEAVER SHEET DELIVERY CONTROL FOR CUTOFF MECHANISMS July 17, 1951 2 Sheets-Sheet 2 Filed Nov. 8, 1946 F a W 4 V ATTO 5*! EYS Patented July 17,

SHEET DELIVERY CONTROL FOR CUTOFF MECHANISMS William H. Cleaver, Audubon, N. J., assignor to Samuel M. Langston 00., Camden, N. J a corporation of New Jersey Application November 8, 1946, Serial No. 708,501

6 Claims.

In the continuous production of stiff sheet material. such as double faced corrugated board, it is necessary that during the continuous advance thereof, successive sections of preselected length be cut from the end of the web. These are either stacked for later use, or are delivered at once to another machine for operation thereon, as for instance, printing, scoring and slotting to make box blanks.

It is customary to run the double facer at a high rate of speed, to obtain the maximum production of web from the machine and often this speed is 400 linear feet per minute, or even higher. Therefore the stiff sections or sheets are traveling at the same speed at the time they are cut from the advancing web. As soon as these sections are cut off it is customary to momentarily increase their speed of travel to space them from, and get them out of the path of. the high speed traveling web.

In order to properly stack the sheets, or to position them properly on a cross-conveyor, it is important that the fast traveling sheets be slowed down and stopped within a short and limited range of travel. This range may not greatly exceed the length of the sheet itself, if the sheets are to be stacked at the delivery end of the double facer, or if they are to be deposited on a closely juxtaposed conveyor traveling at right angles to the direction of travel of the web. If

the speed of the sheet be momentarily increased to get it out of the way of the advancing end of the web, this increases the difiiculty in stopping the sheet in a predetermined position after traveling a further distance approximating its own length.

My invention relates to apparatus for effecting the successive increase and decrease of the speed of sections or sheets which have been cut from the end of an advancing stiff sheet material. such as double faced corrugated board.

An apparatus embodying my invention is shown as applied to a machine having cut-off mechanism from which the successive stiff sheets are delivered onto an endless conveyor traveling at a linear speed greater than the speed of travel of the web to space the sheets from the end of the advancing web.

As an important feature of my invention, I provide two sets of feed members for successive engagement with the cut-off sheets, the first pair serving as sheet feeding means at conveyor speed, and the second pair serving to slow down the sheets.

As a further feature, I provide means whereby the distance between the sheet gripping point of one pair of sheet feeding members may be adjusted toward and from the sheet gripping point of the other pair and in accordance with the length of the sheet' V As a further feature, I provide means whereby the spacing of the sheet gripping and advancing members may be varied in accordance with the thickness of the sheet.

As a further feature, I provide means whereby the spacing of the second pair of feeding members may be increased to permit damaged sheets to pass freely therebetween.

Various other important features will be pointed out hereinafter in connection with the de cription of one embodiment of the invention.

In the accompanying drawings Fig. 1 is a top plan view of an apparatus constructed in accordance with my invention.

Fig. 2 is a side elevation. certain parts being shown in section and a Fig. 3 is a vertical longitudinal section on the line 33 of Fig. 1.

The continuously produced and continuously advanced web A is passed through a cut-off mechani m which is conventionally illustrated as a pair of rotary members It! and II having interengaging knives. The cutting speed of this mechanism is synchronized with the speed of the web but the average rotary speed is controlled during each revolution without varying the cutting speed, to cut off sheets B of the desired length.

As shown. the sheets are delivered onto an endless conveyor which includes a pair of belts l2 and I3 on pulleys l4 and I5, the pulleys it being driven from the same source of power as the web so that the linear speed of the sheet will bear a definite relationship to the linear speed of the web, but the conveyor and the sheet will travel faster than the web. As shown, the pulleys M are driven by a chain l6 from a shaft ll forming a part of, or connected to, the web producing rnd advancing mechanism. An idler is may be employed to keep the conveyor taut.

Adjacent to the pulley 15 and above the conveyor belts l2 and I3 is a roller l9 having a sprocket wheel 2| engaging a chain 22 driven from a sprocket 20 on the shaft of the pulley l5 and extending around a sprocket 23 on the frame of the machine. Thus the roller l9 and the pulley IS in effect constitute a pair of rollers rotating at the conveyor speed. As will later be pointed out. the roller l9 may be adjusted along the path of the sheet, and Without interfering with the drive of the roller I9 as in adjusting its position it moves along the chain 22.

Beyond the pulley .l there are provided a pair of

rollers

24 and 25, one of which is made adjustable for clearance between rolls to permit the sheet to either pass freely or be subjected to a pinch between them, depending upon the adjustment. When the sheet leaves the roller l9, it tilts, and

rollers

24 and 25 rotating at a lower speed, slow down the speed of the sheet. As shown, the roller 24 is driven from the roller I5 which later is driven by the conveyor belts l2 and I3, and the roller I5 is provided with a sprocket wheel 26 connected by a chain 21 to a sprocket wheel 28 loose on a shaft 29. This sprocket wheel is shown as attached to a sprocket wheel 30 connected by a chain to a sprocket wheel 32 on the shaft of the roller 24. The relative sizes of the sprocket wheels are such that the roller 24 is driven at a lower peripheral speed than the conveyor. The chain 21 instead of being driven by the sprocket wheel 26 might be driven from a sprocket wheel on the shaft of a separate motor kept in timed relationship with the motor or from any other source of power driving the shaft H.

The upper roller 25 is mounted on arms 34 secured to the shaft 29 and rests on the sheet, but the low position may be controlled by an adjusting screw 'on one arm 34 and engaging a stop 36 on the frame. This roller is driven by a pair of

gears

33, 33 the latter of which is connected to the sprocket wheel 30. A solenoid is connected to one of these arms 34 so that when the solenoid is energized the roller 25 is lifted out of engagement with the sheet. and later dropped down without interrupting the driving connections. The roller 25 may be lifted at will by rotating the shaft by means of a crank 29'.

Normally the sheet is gripped between conveyor belts l2 and I3 and the roller 19 but the low position of the roller may be limited as the roller is mounted on arms 31 clamped on a transverse tube or sleeve 38. One of the arms 31 has a lug 39 provided with an adjusting screw 48 engaging a stop 4| on one of a pair of slides 42 on the main frame. The sleeve 38 is loosely mounted on a shaft 44 journaled in the slides 42 on the frame and having a hand wheel 45 on one end, and a pair of gears 46 engaging rack bars 41 on the frame of the machine. Thus by rotating the shaft 44 the slides 42 and the roller l9 may be moved toward and from the pair of

rollers

24 and 25 and in accordance with the desired spacing between successive sheets. When adjusted the slides 42 may be clamped to the frame of the machine by clamping members 49.

The construction shown in the drawings is merely one embodiment of the invention. It may rolls and the web. For convenience of explana-.

' tion the latter will be described.

be arranged in different ways to accomplish the result of retarding a delivered sheet of severed board.

The conveyor and set of feeding rolls may be driven from the same source as that which effects the linear speed of the web, and the set of slow down or retarded rolls may be detached from the set of feeding rolls, and driven from another source at a constant or variable linear speed. The conveyor, together with the set of feeding rolls and a set of slow down or retarded rolls, may be attached to and driven at lower peripheral speed by the set of feeding rolls; or the set of slow down or retarded rolls detached from the set of feeding rolls, may be driven from another source either individually or as a unit.

The conveyor, together with the set of feeding rolls and the set of slow down or retarded rolls, may be driven from a common source in relation During changes in the speed of the machine, the percentage of the increased linear speed of the conveyor for the sheets over that of the web remains a constant. Thus if the conveyor linear speed is 20%, 30%, 40% or any other percent greater than the linear speed of the web, the percentage difierence will remain the same, as both conveyor and web are driven from the same source. As the speed of the conveyor is greater than that of the web, there is formed a gap between the end of the web and the rear end of the sheet, which gap increases in length until the next successive sheet is cut off and delivered to the conveyor belts l2 and I3. The longer the sheet the greater will be the gap between successive sheets. On a basis of 20% over-speed of the conveyor and a 30 inch length of blank, the gap between oncoming sheets would be 6 inches; whereas, with a 60 inch sheet, and the same percentage of overspeed, the gap would be 12 inches, etc. The gap thereby created, provides a time factor to permit the slow down

rollers

24 and 25 to reduce the linear speed of the sheet.

As the sheet is cut from the web it is carried forward by the conveyor until it contacts the roll [9 which has been adjusted along the frame of the machine by handwheel 45 to a position determined by the desired sheet length and locked in position by clamps 49. It is also adjusted for pinch of the sheet between roller l9 and conveyor belts l2 and I3 by adjusting the screw 40. As the sheet enters between roll l9, and the conveyor belts and is subjected to the pinching of roll l9, the sheet becomes controlled at conveyor linear speed throughout the length of the sheet.

Roll l9 and the belts i2 and [3 function as a feeding mechanism, feeding the sheets between

rolls

24 and 25, previously adjusted by screw 3'5, with clearance between

rolls

24 and 25 to permit the sheet to enter freely. As the rear end of the sheet passes through between roll I9 and the conveyor belts, the sheet ceases to be controlled at conveyor linear speed, and rolls 24 and 25 become the controlling members and reduce the linear speed of the sheet to the linear speed of

rolls

24 and 25, and discharge the sheet onto a table or conveying system for handling.

Thus it will be seen that as each sheet is cut off it is speeded up by the conveyor and the gap increases in length until the next sheet is cut off. The gap then remains ofthis increased length until the rear end of the sheet leaves the roller [9. Its length is then reduced as the sheet is slowed down by the

rotary members

24, 25, and until the rear end leaves these rollers. While engaging both the roller l9 and the roller 25 it has the speed of roller is and the conveyor. The spacing between long sheets is greater than that between short ones, because the conveyor has carried the cut-ofi sheet farther along before the next sheet is cut off. Although the slow down tendency may be exerted on the sheet as soon as itpasses between the

rollers

24 and 25, the actual slowing is efiected only after the sheet leaves roller l9.

The solenoid, connected to swinging arm 34 may be energized to raise the roller 25 and away from roll 24, to permit the ready discharge of damaged blanks at conveyor speed, and without slowing down its speed. It may be controlled by a manually operated switch.

Having thus described one embodiment of my invention, what I claim is:

1. Mechanism for controlling the speed of sheet delivery from a cut-off mechanism, including in combination with a web advancing means and a cut-off mechanism having a cutter traveling at web speed during the cutting action, a conveyor for receiving the cut-off sheets, and traveling at a speed greater than that of the web, a positively driven feed roller coacting with said conveyor for advancing the cut off sheets, and a pair of rollers positioned beyond the end of said conveyor and spaced from said first mentioned roller to a distance less than the length of the sheet and having a peripheral speed less than that of the conveyor and said first mentioned roller, to slow up the sheet and reduce the length of the gap between successive sheets after they leave the first mentioned roller, said pair of rollers contacting each sheet progressively throughout the length of the sheet as the latter advances, and the pressure on the sheet between said pair of rollers being less than that between the first roller and the conveyor, whereby the sheet travels at the speed of the conveyor while in engagement with the first mentioned roller and the pair of rollers slip on the sheet until the latter is released from the first mentioned roller, and then act to slow down the speed of the sheet and reduce the gap between successive sheets.

2. A mechanism as defined in claim 1, in which there is provided means for varying the spacing between said first mentioned roller and said pair of rollers.

3. A mechanism as defined in claim 1, in which there is provided means for adjusting the position of the first mentioned roller along the path of the conveyor.

4. A mechanism as defined in claim 1, in which there is provided means for increasing the spacing between said pair of rollers to permit free delivery of the sheets between said rollers.

5. Sheet delivery apparatus for a cut-off mechanism acting on a stifi continuously advancing web, said mechanism including a sheet conveyor, means for operating it at a higher speed than that of the sheets at the instant of being delivered thereto, whereby the sheets become spaced apart on the conveyor, a roller above said conveyor for engaging the sheets, means for driving said roller at the same peripheral speed as the linear speed of the conveyor, means for adjusting the position of said roller along the path of movement of said conveyor, 9. pair of rotary members beyond said conveyor for delivering the sheets received from the conveyor, means for driving said last mentioned members at a lower peripheral speed than the linear speed of the conveyor, and means per-' 6. Sheet delivery apparatus for a cut-oil mechanism acting on a stifi continuously advancing web, said mechanism including an endless conveyor onto which the sheets are delivered, means for operating said conveyor at a higher speed than that of the sheets at the instant of being cut and delivered thereto, whereby the sheets become spaced apart on the conveyor, a roller above said conveyor for pressing the sheets onto the conveyor, means for adjusting the position of said roller along the path of movement of said conveyor for sheets of different length, means for driving said roller at the same peripheral speed as the linear speed of the conveyor, a pair of rotary members beyond said conveyor for engaging said sheets, and means for driving said last mentioned members at a lower peripheral speed than the linear speed of the conveyor, said members permitting the sheets to pass therebetween at higher speed than the peripheral speed of said members while engaged by the first mentioned roller, and acting to slow down the sheets when free of said conveyor.

WILLIAM H. CLEAVER.

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

Myers May 4, 1943