Paper tail cutter

Abstract

A paper tail cutter for cutting a leading edge upon and deflecting a tail from a moving sheet of paper. A cutter body member is pivotally mounted to swing a knife up through the path of the moving sheet of paper, thereby cutting to engage a narrow, previously severed, tail at one side of the moving sheet. The tail is supported by the body member and deflected away from the moving paper sheet as the leading edge is simultaneously cut thereon for delivery to apparatus such as a stack of calender rolls.

Description

FIELD OF THE INVENTION

This application pertains to a paper tail cutter for cutting in a moving sheet of paper20 is cut to one side of sheet 12 by conventional means (not shown). This tail is more easily handled and threaded through the calender stack and is then used to draw the full width of sheet 12 through the calender stack. More particularly, paper tail cutter 19 (best seen in FIG. 2, but also illustrated in FIGS. 3 and 4) cuts a the narrow tail 20 to one side of sheet 12 form a smooth leading edge thereon and deflects tail 20 away from the balance of sheet 12 to conveyor apparatus 21 which in turn delivers tail 20 to the calender stack. The balance of sheet 12 falls into broke pit 16 for reprocessing.

Paper tail cutter 18 comprises a body member 24 which is pivotally mounted, at end 26, on axle 28 which is in turn rotatably mounted in the upper or "first" leg 27 of rigid U-shaped frame 29. This mounting enables body member 24 to swing about axle 28 up through the plane traversed by moving paper sheet 12 as the sheet falls into broke pit 16. This swinging action carries the opposed end 30 of body member 24, to which first knife 32 is affixed into sheet 12 tail 20 thus forcing sheet 12 tail 20 up towards second knife 34, which is fixed in the lower or "second" leg 36 of frame 29. The desired swinging action is provided by a powered means such as compressed air cylinder 38 which is coupled between frame 29 and body member 24 to pivot body member 24 as aforesaid and force first knife 32 and moving sheet 12 tail 20 across second knife 34. Since second knife 34 is fixed with respect to first knife 32, a scissor-like cutting action occurs between the knives, thus cleanly severing a portion of sheet 12 to yield tail 20 which is then to form a clean leading edge thereon, the tail 20 being supported on the surface 40 of body member 24. Surface 40 is a smooth steel plate.

Tail 20 slides off end 30 of body member 24 and may then be transferred to conveyor apparatus 21 (preferably a vacuum tail transfer unit) or to other suitable means for conveying tail 20 to the calender stack and for threading tail 20 through the calender stack. Advantageously, surface 40 is troughed, for example by providing it with raised side 42 to retain and guide tail 20 on and over surface 40. Preferably, surface 40 is appreciably wider than tail 20 to further assist accurate guidance of tail 20 over surface 40.

The edges of knives 32, 34 are preferably contoured to cut a shaped end on tail 20, thereby further easing machine handling of tail 20. More particularly, the knife edges are preferably contoured to provide a shallow "V"-shaped point on the end of tail 20 which can more easily be fed through the infeed nips of the calender stack. Advantageously, knives 32, 34 are removably and adjustably affixed to body member 24 and leg 36 respectively. This facilitates rapid removal of dulled knives and replacement thereof with sharpened knives. Adjustment of knives 32, 34 relative to one another to yield a clean, even cut is accomplished by proving a plurality of slotted apertures (not shown) in each of knives 32, 34 through which recessed hold-down screws (which may be back set) are fastened to hold the knives against body member 24 and leg 36 respectively.

To avoid obscuring details of the invention FIG. 2 shows paper tail cutter 18 in its retracted position beneath moving paper sheet 12 tail 20. Accordingly, both tail 20 and the balance of sheet 12 are shown falling towards broke pit 16. In practice however, the swinging action of body member 24 deflects tail 20 away from sheet 12 towards conveyor apparatus 21 which, once tail 20 has been cut, draws tail 20 across its surface, away from the balance of paper sheet 12, for eventual threading through the calender stack. After tail 20 has been cut and guided onto conveyor apparatus 21, paper tail cutter 18 may be retracted to the position shown in FIG. 2 so that it does not interfere with movement of paper sheet 12 when the full sheet is drawn through the calender stack.

FIGS. 5 and 6 illustrate an alternate embodiment of the invention which differs from that shown in FIGS. 2, 3 and 4 only in respect of the arrangement for mounting and supporting body member 24. More particularly, body member 24 of the embodiment in FIGS. 5 and 6 is supported by axle 48 which is coupled at one end to frame 50, without the need for a support leg 27 as provided in the embodiment of FIGS. 2, 3 and 4. As may be seen in FIG. 6, air cylinder 52 which pivots body member 24 is recessed within frame 50. The embodiment of FIGS. 5 and 6 is somewhat more compact than that of FIGS. 2, 3 and 4 and may thus be used in more confined areas within the paper making machinery setup.

As will be apparent to those skilled in the art in the light of the foregoing disclosure, many alterations and modifications are possible in the practice of this invention without departing from the spirit or scope thereof. Accordingly, the scope of the invention is to be construed in accordance with the substance defined by the following claims.

Claims

1. A paper tail cutter for cutting and deflecting a moving paper tail from an edge of a moving sheet of paper and cutting said tail transversely, said paper tail cutter comprising:

(a) a body member for supporting said moving paper tail, said body member pivotally mounted, at one end, so that the opposed end of said member may swing through the plane traversed by said moving paper sheet; and,

(b) a first knife at said opposed end;extending transversely of said body member; and,

(c) a second knife fixed with respect to said first knife to provide a scissor-like cutting action between said knives when said body member pivots to swing said first knife across said second knife;

whereby pivotal movement of said body member and said first knife relative to said moving paper sheet cuts a portion of said moving paper sheet to yield said moving paper tail and continued pivotal movement of said body member deflects said moving paper tail away from said moving paper sheet and cuts said tail transversely.

2. A paper tail cutter as defined in claim 1, further comprising a second knife fixed with respect to said first knife to provide a scissor-like cutting action between said knives when said body member pivots to swing said first knife

across said second knife. 3. A paper tail cutter as defined in claim 2 1, wherein said body member has a troughed surface

for retaining and guiding said paper tail. 4. A paper tail cutter as defined in claim 3, further comprising powered means for pivoting said

body member to force said first knife across said second knife. 5. A paper tail cutter as defined in claim 4, wherein, said knives have edges contoured to cut an end of said tail shaped to ease machine handling of

said tail. 6. A paper tail cutter as defined in claim 5, wherein said

knife edges are contoured to cut a "V"-shaped end of said tail. 7. A paper tail cutter as defined in claim 4, wherein said body member is normally retracted to a position beneath to one side of the path of said moving paper sheet, and wherein said second knife is fixed in position above on the opposite side of said path of said moving sheet, whereby operation of said powered means pivots said body member through said path of said sheet to deflect

said tail away from said sheet. 8. A paper tail cutter as defined in claim 7 further comprising a "U"-shaped frame having a first leg for pivotally mounting said one end of said body member and having a second, opposed leg for supporting said second knife.