US3166966A

US3166966A - Operating upon sheets of foil

Info

Publication number: US3166966A
Authority: US
Inventors: Henry F Ruschmann
Original assignee: Individual
Current assignee: Individual
Priority date: 1961-02-14
Filing date: 1962-07-18
Publication date: 1965-01-26
Anticipated expiration: 1982-01-26

Description

Jan. 26, 1965 H. F. RUSCHMANN OPERATING UPON SHEETS OF FOIL 4 Sheets-Sheet l W m a T N mwl m s ./T mu T R A F n Y W R I E H Original Filed Feb. 14 1961 Illlllll IIIII Jan. 26, 1965 H. F. RUSCHMANN OPERATING upon SHEETS 0F FOIL 4 Sheets-Sheet 2 Original. Filed Feb. 14. 1961 FIG. 4

INVENTOR HENRY F. RUSCH MANN ATTORNEY 2 2 L 7 9 9 9 6 6 4 8 I B 6 Jan. '26, 1965 H. F. RUSCHMANN 3,166,956

OPERATING UPON SHEETS OF FOIL 4 Sheets-Sheet 3 Original Filed Feb. 14 I961 INVENTOR BYHE Y F RUSCHMANN ATTORNEY Jan. 26, 1965 H. F. RUSCHMANN 3,166,965

OPERATING UPON SHEETS 0F FOIL Original Filed Feb. 14, 1961 4 Sheets-Sheet 4 F l G. 9

IN VEN TOR,

United States Patent 3,166,966 OPERATENG UPGN SHEETS @F FGIL Henry F. Ruschmann, Mine Brook Road,

Eernardsville, NJ. Original application Feb. 14, B61, Sci". 1%,775. Divided and this application July 1th, 1962, er. No.

12 Elaims. (Cl. 83--262) This application is a division of my copending application Serial No. 100,755, filed February 14, 1961.

This invention relates to operating upon sheets of foil, especially though non-limitatively lengthy sheets such as are usually handled in rolled arrangement. The foil which the invention contemplates may be either of metal (of which one example is aluminum), or of organic material (of which one example is cellulose acetate), or of combined materials such as metal coated with, or laminated together with films of, organic material.

It is an object of my invention to provide improved apparatus for the cutting or shearing of foil, especially though non-limitatively for effecting repetitive cuts close to one another. Other and allied objects will appear from the following description and the appended claims.

The invention comprises an apparatus in which suitable knife means are reciprocated along a cutting surface to shear a sheet of foil being fed transversely to that surface; in which preferably the reciprocation is in timed relation to the feeding; in which the knife means may shear the sheet for less than its full width; in which continuous lubrication may be fed to the plane of contact between knife means and cutting surface; in which the stroke of the knife means and its distance of penetration through the sheet are interrelated to permit continuous feeding;

and in which other features as well contribute to an adaptability of the apparatus to relatively high-speed operation.

By way of example the invention is hereinafter disclosed in connection with the production of slivers-- e.g., strips of narrow (for example, .005") width, of limited (for example, .375) length, and of thickness of such a general order of magnitude as .O0l"-of foil. (One use of such slivers is their dispersion throughout another substance such as a solid foam or organic material, the resulting product finding important application in installations for the detection of aircraft, missiles and the like) Such slivers are required to be of precise dimensions, and are accordingly a product which nicely emphasizes the precision with which apparatus according to my invention operates; it will be understood, however, that there is intended no unexpressed limitation of the invention to the production of slivers.

In the detailed description of my invention hereinafter set forth reference is had to the accompanying drawing, in which:

FIGURE 1 is a righthand elevational view of an apparatus or machine according to my invention for converting the original foil sheet into a web, or ladder of which the slivers at this stage form the rungs, but with the knives and their holders and the knife carriage and its guides omitted;

FIGURE 2 is a perspective view of the cutting surface and of the blocks which form and integrate it;

FIGURE 3 is a front elevational view of the apparatus as seen immediately to the rear of the elements shown in FIGURE 2, being taken along the line 3-3 of FIG- URE 1;

FIGURE 4 is a horizontal cross-sectional view taken along the line 44 of FIGURES 1 and 3, this and later figures including a showing of the knives, knife holders, knife carriage, etc.;

FIGURE 5 is a perspective view of the guide plate as sociated with the upper feed roller;

ice

FIGURE 6 is a vertical cross-sectional view taken along the line 66 of FIGURES l, 3 and 4;

FIGURE '7 is a front elevational view of the apparatus;

FIGURE 8 is an enlarged fractional horizontal crosssectional view, taken along the line 8-8 of FIGURE 7, through a portion of the lower knife;

FIGURE 9 is a perspective View showing the web emerging from apparatus such as that of earlier figures and being suit-ably rolled up;

FIGURE 10 is a greatly enlarged longitudinal crossscctional view of a minute length of the web as and just after it has so emerged; and

FIGURE 11 is a perspective view of a web having only marginal longitudinal bands.

Reference now being had to the drawing and initially to FIGURE 1, there will be seen a bed 1 along the top of which there may be fed forwardly-4e, leftwardly as seen in FEGURE l a sheet of foil. The bed 1 may be provided at its forward corners with upright rectangul-ar posts 2, and at its sides somewhat to the rear of posts 2 with upright rectangular posts 3; these four posts are shown as integral with the bed, but it will be understood that they may be separate elements attached in any convenient manner. The forward portion of the bed 1 may be secured on top of the relatively large spacing block 4, for example of similar width to that of bed 1. Immediately forward of the bed l and front posts 2 and spacing block 4, and secured to those elements, may be the vertical transverse block it of medium horizontal thickness, provided at the level of the top of the bed with a vertically thin horizontal slit ll) (seen in dotted lines in FIGURE 1) through which may pass foil which has moved forwardly along the top of the bed. To the front surface of the blocl; ill, and as seen both in FIGURES 1 and 2, there may be secured the

blocks

13 and 14, permissibly somewhat thinner horizontally, the former below and the latter above the level of the slit it The blocks 13 and M are vertically separated by a slot 12 aligned with the slit lit, the vertical dimension of slot 12 and that of the forward portion of slit ltl being somewhat, but preferably only slightly, greater than the thickness of the foil to be operated upon-it being understood that in many of the figures of drawing this dimension has been relatively exaggerated for the sake of clear illustration.

The slot 12 forms, in the cutting surface, a thin orifice through which the sheet of foil may be fed. The sheet is propelled forwardly, to emerge from the orifice, by mechanism seen in FIGURES l, 3, 4 and 6. Basically this mechanism comprises a pair of transversely arranged horizontal rollers 21 and 22 (see FIGURE 6). The roller ill is located below the plane of the: top of the feed bed 1 in a cut-away space 111 (see FIGURES 3 and 6) provided, at the front of the bed ll throughout its central portion, between side portions la of the bed which are conveniently of somewhat greater width than that of the

posts

2 and 3, and its shaft 23 may be journalled in those side portions la. The roller 22 is located vertically above the roller 21 and above the plane of the top of the feed bed 1, its shaft 24 being journalled in blocks 15 whose position inahorizontal plane is established by the

posts

2 and 3 but which may move vertically in a locus established by those posts. Each of the two blocks 15- resting on a respective end portion 35 of a guide plate 32, through an aperture in which the roller 22 extends downwardly and which is hereinafter more detailedly described--has its main portion between the

respective posts

2 and 3, but has an inner flange portion 16 of greater dimension in a front-and-back direction and overlapping the posts in that direction; the flange portions 16 are maintained substantially in contact with the posts by the roller 22.

' referred to above. ing system may comprise the transversely arranged guide 7 as mentioned above; between slightly therebelow while being 32 will then be spaced from bed land lower guides plate 32. is a movable rather than a un The lower roller may be wholly of metal, preferably with a polished surface. The upper roller 22 is desirably provided with a rubber surface layer 20, preferably of external diameter similar to that of the lower roller 21, the length of which may if desired be limited to coincide V with that of the lower roller.

The guide plate 32 is subjected to upward bias, as by cantilever wire springs 31 secured to and extending forwardly from more rearward side portions (not indicated) of the bed 1 to have their forward end portions underneath the outwardly projecting end portions of the guide plate 32; this upward bias of course also biases upwardly the blocks and thus the upper roller 22. T his upward bias of the upper roller serves to separate the two rollers for loading, or threading of a sheet of foil through, the apparatus. After such loading has been accomplished the blocks 15, and thus the upper roller 22 (and the guide plate 32), will be pressed downwardly, overpowering the bias mentioned above, so that the upper roller presses against the lower roller with the sheet of foil therebetween. This downward pressing may be accomplished by a relatively large and powerful bow-shaped leaf spring 17, whose downwardly inclined end portions nay be loosely retained between the posts 2 and f1 and may rest on top of the blocks 15. The central portion of this spring may be pressed downwardly, and the force of the spring thus exerted on the blocks and roller and plate,

can;

by a lever 13 pivoted to the upper end portions of

righthand posts

2 and 3, movable to a horizontal springcompressing position in which its lefthand portion lies between the upper end portions of

lefthand posts

2 and 3, and restrainable in that horizontal position as by a lock such as 19 pivotally mounted to the top of the rear lefthand post 3.

V The sheet of foil is propelled forwardly in order to carry it through the slit it? and the slot 12. In order to in sure that it passes to the slit fit it is desirable to provide a suitable guiding system. Below the path of the foil the guidin system may comprise the lower guides 29 and (see particularly FIGURE 6) having top surfaces in alignment with that of the bed 1, guide 29 ex- 1 tending from the bed to a little behind the uppermost or longitudinally central line along the surface of the lower roller 21, and guide 3t) extending from a little forward of that line to the block 11. The surfaces of these guides closest to the roller 21 are of concave cylindrical-section formconforming to the surface of but slightly spaced from that roller. Guide 29 may be supported in forwardly extending cantilever arrangement from the non-marginal' portion of the bed 1, while guide 34B may be supported at its ends on the beds front side portions la Above the path of the foil the guidplate 32 which has already been mentioned and which in its entirety is seen in FIGURE 5. This may have the end portions each of which extends between a respective pair 2-3 of posts and outwardly therebeyond to be pressed up against by a respective one of the springs 31 the end portions the guide plate may have a main portion 33 provided with a central cut-out 34 of concave cylindrical-section form which conforms to the surface Ztl of the upper roller and downwardly through which that roller may extend to protrude held by its journalling blocks 15 very slightly spaced from the concave surfaces of the'cut-out. 1

It will be appreciated that the limit of downward movement of the blocks 15 and upper roller ZZand guide plate "32 by spring 17 will be established by that roller pressing against'the lower roller 21 with the foil therebetween, and that the parts will be so dimensioned that guide plate under and beyond the blocks element and furthermore is not in intimate contact with the rear of block if) it is desirable to provide in the rear portion of the slit it) some tolerance to slight variations in the level of the leading edge of a newly loaded sheet of foil. This is readily done by slightly flaring the slit lltl so that at its rear extremity it is vertically somewhat wider than at its front, as seen in FlGURE 6.

It will be understood that the function of the apparatus as thus far described is to feed or advance the sheet of foil forwardly along the bed 1 and through the slit lit and the slot .2, and that this is accomplished by rotation of the lower and

upper rollers

21 and 22 etween which the foil is pressed. To provide for this rotation the

shafts

23 and 24 of those respective rollers are provided at their righthand ends with

respective gears

25 and 26 which intermesh when the upper roller is brought down 12 is operated upon by knives; the fronts of the blocks 7 13 and 14 together form a cutting surface, lapped to a thoroughly smooth plane state, along which the knives operate. As to positions along the plane of the cutting surface the knives are held in respective knife holders, and these are mounted in a knife carriage which is reciprocated along vertical guides. This structure may now be described with reference to FIGURES 1, 4,. and 6 already referred to and the further FIGURES 7 and 8.

To the bottom of the block 4 there may be secured the base 5 which extends a substantial distance forwardly H and 13 (see FIGURE 1) and a substantial distance transversely in each direction beyond the block 4 (see FIGURE 7). Near the two front corners of the base 5 there may extend upwardly from that base respective cylindrical carriage guide rods 39 (see FIGURES l, 4 and 7). On these rods the carriage, designated as til, may be arranged for up-and-down reciprocation. The carriage may comprise leftand righthand vertical end members 42 each surrounding a respective one of the guide rods 39; each of these end members slot 43, and secured in and extending between the two slots 43 may be a carriage plate 44- whi h with the end members 42 forms the unitary carriage it The front and-back position of the carriage guide rods 39 is such as to bring the rear of the carriage plate 442 very close to, though slightly spaced forwardly from a condition of actual contact with, the cutting surface formed by the fronts of

blocks

13 and 14. V

On the outer side of each carriage end member 42 there may be provided a central boss 45, to which may be secured the sphere portion46 of a respective spherical rod end 47.. Each of these'rod ends forms the upper portion of a respective connecting rod 48, which at its lower extremity is provided with a respective rod bearing 49. Each rod bearing 49 is fitted about a respective horizontal pin 5t extending outwardly from a respective solid cylindrical element 51, the two elements 51 being coaxially disposed below the base 5 and arranged for simultaneous rotation. The pins 5@ have a common axis which is, however, displaced somewhat from the axis of the elements 51, so that the pins move eceentrically when those elements are rotated; this eccentric movement is of course transmitted by the rods.

43 to the carriage 4d, where it manifests itself as a reciprocating vertical movement of the V carriage guide rods 'To provide for rotation of the elements 51 they may be secured on the respective ends of a carriage along the 7 horizontal main shaft 52 which is journalled in the plane of the guide rods 39 in

suitable blocks

7 and 8 extending downwardly from the base 5. Between these blocks there may be secured on the main shaft 52 a pulley 53, for example suitable to be driven by a V-belt, and it will be understood that it is by the driving of the pulley 53 that the elements 51 are rotated and the carriage subjeced to reciprocating movement. It is also desirably this same driving of the pulley 53 which causes the turning of the gear 27 described above, and thus the feeding or advancement of the sheet of foilit being desirable in particular that the gear 27 be positively (i.e., non-slippingly) coupled with the pulley 53, this resulting in a definite predetermination of the relationship between the frequency of carriage reciprocation and the speed of foil advancement.

To cause the driving of the pulley 53 to turn the gear 27 there is secured on the main shaft 52, next to the pulley 53, a gear 54 which engages a gear d5 positioned therebehind and secured on the lefthand end of a secondary shaft 55. This secondary shaft may be journalled in the block 8, and in a block 9 extending downwardly from the righthand end portion of a shelf ti which itself extends rightwardly from the base 5. At its righthand extremity the secondary shaft 56 may carry the gear 57, which through a suitable coupling gear 52; drives a gear 59 secured on the input shaft as of a suitable speed reducer 61; this speed reducer, desirably of the gear-operated variety in order that its action may be positive, may be mounted on the shelf 6. It is on the leftwardly extending output shaft 62 of this speed reducer that the foil-advancing gear 27 is secured.

In directing attention to the knife holders and knivesof each of which there is desirably a lower as well as an upper one-it may first be mentioned that the carriage plate id is provided with a large central cut-out 44d resulting in its exposed portions being the margins 44a adjacent the respective carriage end members 42 and, extending transversely therebetween, a bottom strip 44b and a top strip 440. The lower knife holder 65 is a horizontal strip extending between the plate margins 44a, having a thickness of which the major portion is aligned in a front-and-back direction with that of the carriage plate 44, but having additional forward thickness which is used to form flanges 67 overlying the fronts of the plate margins; it may be held to the plate margins as by screws 71 passing through vertically elongated holes 69 in the flanges 6'7. The upper knife holder 66 is a similar strip, extending similarly and having similar flanges 68; it may be held to the plate margins as by screws 72 passing through vertically elongated in those flanges.

In its upper portion the lower knife holder 65 is provided with a wide dovetail cut-out 73, and in its lower portion the upper knife holder 66 is provided with a similar cut-out 74-; it is by fitting of their heels into these dovetail cut-outs that the knives are held by the knife holders as to movement along the plane of the adjacent cutting surface formed by the fronts of

blocks

13 and 14. The lower knife, designated as fit, is in the form of a wide vertically short piece of hardened maholes 'Ttl terial, of thickness typically of the same order of mag-.

nitude as that of the knife holder es, approximately the lower half of which constitutes its heel 83 and is fitted into the dovetail cut-out 73; from the heel the knife 81 extends in its full thickness upwardly for a short further distance, and thereabove its front surface isbevelled rearwardly to intersect its rear surface in the upwardly directed cutting edge 85. The upper knife, designated as 82, is in the form of a similar piece of hardened material of similar thickness, approximately the upper half of which constitutes its heel 84 and is fitted into the dovetail cut-out 74; from the heel 84 the knife 82 extends .in its full thickness downwardly for a short further distance, and therebelow its front surface is bevelled rearwardly to intersect its rear surface in the downwardly directed cutting edge 36. The rear surfaces of the knives 8i and 82 may be provided with respective

horizontal grooves

87 and 88 of relatively substantial vertical dimension (see FIGURE 6), thereby among other things minimizing the knife area which will frictionally engage the cutting surface formed by the fronts of blocks 13 and ll l.

The lower knife 81 is biased, into contact of its rear surface with the cutting surface formed as mentioned above, by a pair of relatively wide leaf springs 95 of which the lower portions are held between horizontal strips 97 clamped to the front of the bottom carriage-plate strip 44b as by screws 99; from those strips 97 the springs 95 may curve spacedly around the knife holder to press their rearwardly directed upper edges into a horizontal groove 93 provided at about the vertical mid-line of the front surface of the lower knife. The upper knife is biased into contact of its rear surface with the cutting surface by corresponding springs 95 whose upper portions are similarly held between horizontal strips Qdsimilarly clamped to the front of the top carriage-plate strip Mic, from which strips 98 the springs 96 may curve correspondingly to press their rearwardly directed lower extremities into a horizontal groove 94 similarly provided in the front surface of the upper knife. It will be understood that as a result of this arrangement the rear surfaces, and thus the cutting edges, of the knives are maintained dependably in contact with the cutting surface, without impairment of that contact by possible minor malalignments of the carriage guide rods 39 or the likeyet that by reason of the dovetail fitting of their heels in the knife holders the knives are positively held against shifting relative to the carriage along the plane of the cutting surface, and are subjected to the vertical reciprocating movement of the carriage.

It may here be mentioned that it is desirable to minimize the mass of the carriage and the parts carried thereby, in order to permit a maximum speed of operation of the apparatus together with a minimum vibratory effect of that apparatus. It is for this reason among others that the carriage is principally-constituted by the relatively thin and largely cut-out plate 44.

in order to permit relatively high-speed operation of the apparatus and at the same time to preclude galling of the rear surfaces of the knives and of the: cutting surface formed by the fronts of

blocks

13 and 14, it is desirable to provide a suitable continuous lubrication along the plane of contact of those surfaces. For this purpose the forward surfaces of the lower and

upper blocks

13 and 14 may each be provided with at least two oil-outlet holes, Trill and M62 respectively (see FIGURES .2 and 6). The holes 1692 in the upper block 14, may communicate with respective vertical holes its leading to the top of that block, where the holes itld may in turn communicate with respective oil-supply tubes res concentric therewith and extending upwardly from that block. The holes fill in the lower block may communicate first with respective horizontal holes N3 which extend to near the outer edges of that block and there communicate with vertical holes fills leading to the top of that block, where the holes 1695 may in turn communicate with respective oil-supply tubes Hi7 concentric therewith and extending upwardly from that block; the lower block 13 is made wider than the upper block 14 in order to accommodate the arrangement just described. (Illustration of the righthand vertical hole res and oil-supply tube lill' has been omitted from FIGURE 2 to avoid interference with other features of that figure.)

Distribution of the oil emerging from the oil-outlet holes fill and 3192 over the cutting surface and the rear surfaces of the knives is facilitated by the

grooves

87 and 83 formed in the knives as mentioned above, and may be still further facilitated by light diagonal grooving, schematically indicated as 1%, cut in the front surfaces of the blocks 13 and its.

and" therefore to reach and upwardly pierce a 35 as being minutely'below the slot 12, may be taken as illustrating the condition of the apparatus with the carriage in the position which it will occupy slightly prior t or slightly after reaching the top of its stroke; these alternative conditions are those for which the pin and rod bearing 4? in FIGURE 1 have been presented. if it be assumed that the main shaft 52 is driven counterclockwise as seen in FIGURE 1 (which it will be if the input and output shafts of the speed reducer 6h turn in the same direction), then FIGURE 1 uniquely illustrates the condition of the apparatus when the carriage is approaching (rather than receding from) top position, and it will be convenient to consider FIGURE 7 as illustrating the same condition. In these figures, then, the knife edge 55 is about to reach and pass upwardly over the slot 22, sheet of foil being fed forwardly out of that slot. As the operation of the apparatus continues the knife edge 85 will reach and upwardly pierce the foil, progressing a minute distance therebeyond and then receding downwardly.

' Correspondingly the cutting edge of the upper knife will be adjusted so that when the carriage has reached the bottom of its stroke that edge will have been lowered to a similar minute extent below the bottom of the slot I2. Accordingly at a time one-half cycle-a cycle being one revolution of the main shaft 52, or one full up-anddown reciprocation of the carriage-later than that at which the knife edge 85 reached and upwardly pierced the sheet of foil from below, the cutting edge as will reach and downwardly pierce it from above, progressing a minute distance therebeyond and then receding upwardly. Still one-half cycle later the cutting edge 85 will again reach and upwardly pierce the sheet, and so on in a continuous alternation. The sheet being meanwhile steadily advanced between the

rollers

21 and 22, the effect of the alternate piercing thereof by the two knives is to subject the sheet to shearing, twice in each cycle, along parallel transverse lines Whose separation each from its neighbor is the distance by which the sheet advances during each half cycle. The magnitude of that separation may of course be controlled by choice of the gearing (including the reduction ratio of the speed reducer 61) lying between the main shaft 52 and the

rollers

21 and 22.

FIGURE 6 will be understood to illustrate the carriage at a position a little below the mean between its uppermost and lowermost positions.

' In the discussion above no special attention has been paid to the fact that the slot 12 will have a vertical dimension at least slightly greater than the thickness of the foil,

with the result that adjacent the orifice in which the slot at its front terminates the sheet of foil may be capable of being slightly displaced by the knives up and down within the slot before being actually pierced. In clarification it may be pointed out that by reaching-the sheet of foil there is meant above a reaching (by the knife edge) of the adjacent one of the sheets surfaces under a condition of the opposite surface of the sheet being in contact adjacent the orifice with the corresponding surface of the slot 12.

It may be mentioned that from the time either knife edge reachesand has begun to pierce the sheet of foil, on to the time that edgehas arrived at a corresponding position in its receding movement, the rear surface of that knife will tend to act as a closed gate across the slot is, temporarilyinterfering with the emergence of the sheet of foil through the orifice in which that slot terminates unease-3e at 'its front. With typical minute distances of further travel of the knife edges after reaching and just passing through the sheet (i.e., as mentioned above) and with typical lengths of stroke of the carriage (e.g., .200), the percentage of a half-cycle during which this closedgate action will occur will be of the order of 15% or less. This percentage of the separation between the transverse paths of shearing of the sheet is ordinarily a very small percentage indeed of the distance from the cutting surface to the line of contact of rollers Zll and 22 with the sheet, and the sheet readily accommodates to the short stoppages at the cutting surface by minute digressions from plane condition within the last-mentioned distance. It will of course be appreciated that one of the two knives might be omitted, with the results that the shearing would occur only once in each cycle, and that the separation between the parallel transverse paths of shearing would be the distance by which the sheet advances during the whole cycle. This is ordinarily disadvantageous, since the ultimate limitation on the quantity (i.e., length) of foil operated on per unit of time by an apparatus of this character is in general not the speed by which the sheet of foil may be advanced, but rather the maximum practical frequency of reciprocation of the carriage, which maximum does not shift appreciably whether both or only one of the knives be employed; it follows that that quantity per unit of time is substantially twice as great with two knives as with one. The use of the two knives has further advantages as well, which have to do with the roduct of the operation of the apparatus and which are hereinafter set forth.

The knives have been thus far described withoutrefer ence to any special characteristics of their cutting edges in the direction transverse of the apparatus. If those cutting edges were to be continuous in that direction and were to extend to the edges of the sheet of foil, the operation of the apparatus would of course produce individual transversely cut strips of foil, each of a length equal to the width of the sheet and of a width equal to the distance by which the sheet advances every half cycle. To produce other results those cutting edges may be made discontinuous, and/or may be terminally limited, in appropriate manners.

To produce the web described early hereinabove the' cutting edges of the knives may be subdivided into a plurality of transversely spaced sections. Thus the lower knife 81 may be provided with a plurality of vertical cuts extending for at least a very short distance down wardly from the cutting edge 85, each cut having a width equal to the width of the respective longitudinal band which it is desired be present in the web; the upper knife 82 will be provided with a corresponding plurality spacings of the cuts from the ends of the knives and from each other will desirably be made uniform, to result in uniform inter-band dimensions in the web.

In order to insure that the sides of the cuts 8% and i will not produce unintended tears at the extremities of the lines of shearing of the sheet of foil by the adjacent sections of the knife edges, it is desirableto bevel those sides of the cuts so that they intersect the, rear surfaces of the knives at an acute angle and thus them selves form with those rear surfaces vertical short cutting edges. This has been illustrated by the bevelled surfaces 91 and on the lower and upper knives, respectively, in FIGURE 7 but may be better seen in the en-.

larged fractional cross-sectional showing of FIGURE 8. The ends of the knives should of course be provided with similarly bevelled surfaces 91 and 92, as has been indicated in FIGURE 7.

FIGURE 9 illustrates the

knives

81 and 82 of earlier figures, with a sheet of foil emerging forwardly from between the knives-by which it has been operated on so that it has been converted into a web 110 such as hereinbefore mentioned; in the interest of simplicity the widths of knives and web have been broken off, but it will be understood that no necessary differentiation from the showings of earlier figures is thereby intended. In this figure there will be seen in the web the longitudinal bands 111 which by reason of the cuts 89 and 90 in the knives are left unsheared, and in the longitudinal paths between those bands a succession of transverse strips 112 which are very narrow-i.e., of very small dimension longitudinally of the web 110, which dimension may if desired be much smaller than that indicated in this figure and which merge at their extremities with the bands 111.

FIGURE 9 also illustrates the winding up of the web on a cylinder or spool 115 suitably carried on a mandrel 116 which, by means themselves well understood and not herein necessary to show, is slip-driven to wind up the web as fast as it emerges from the apparatus, but without placing the web under longitudinal tension sulficient either to distort it or to affect the operation of the ap paratus from which the web emerges.

FIGURE illustrates a typical cross-section taken longitudinally through the last few transverse strips 112 of the web to have been formed by the knives, and through a contiguous short portion of the sheet which is about to arrive at the knives, all in very greatly exaggerated size; it also illustrates in dash-dot lines the cross-section of the end portion of one of the knives (by way of example, the upper knife 82) atsubstantially its extreme (e.g., lowermost) position. The strip 112 which is in contact with the bevelled front of the knife 82 will be seen to have been rocked by the knife front counterclockwise as seen in this figure-i.e., to have been displaced downwardly adjacent its rear edge-about its forward edge into an inclination downwardly out of the plane of the longitudinal bands 111; it (as well as the second, fourth, etc. strip which is located forwardly from it and which will of course have been similarly affected by the same knife) is specially designated as 1112b. On the other hand the intervening strips 112 will have been conversely affected by the lower knife 81; each will have been rocked by the front of that knife clockwise as seen in this figure-i.e., will have been displaced upwardly adjacent its rear edge-about its forward edge into an inclination upwardly out of the plane of the longitudinal bands 111, these intervening strips being specially designated as 112a.

What has just been said of course applies to the strips 112 throughout their lengths (i.e., dimensions transverse of the web) excepting at their very end portions 113 in immediate adjacency to the longitudinal bands 111; within those end portions 113 the strips 112 of course progressively lose their inclinations, to merge into the longitudinal bands in the plane of the latter.

It may here be stressed that the feature of alternate inclinations of the strips 112 just described-which without dimculty survive the rolling up of the web on spool 115 so long as the slip-drive of the mandrel 116 is adjusted to avoid unnecessary and excessive longitudinal tension on the web in the winding-up processhas several distinct advantages.

Some of these advantages spring from the resulting greater openness of the web, not only in comparison with a web formed by shearing but with no inclination of the strips (which would tend to be devoid of openness), but also in comparison with a web formed with inclination of all of its strips in the same direction. One such advantage has to do with surface treatment of the web, such as de-greasing, drying, oxidizing, coating with lacquer or other agents, etc.; this advantage is that the high degree of openness of the web provided by the alternate inclinations of the strips facilitates the access of the treating agents-whether solvent, air, oxidizer, lacquer or other coating agent, or still other agentto all the surfaces of the web. Another such advantage has to do with novelty adaptations, wherein the alternate inclinations increase the degree of semi-transparency of the web material between the longitudinal bands, while at the same time increasing to number of directions from and to which light reflections will be effected by that portion of the web. Still another such advantage has to do with fiuid-iltering uses, for which the alternate inclinations afford new combinations of perviousness with area, strength and other parameters.

Another class of advantage has to do with uses in which there may be desired a distinction in freedom of move ment of the web surface along another surface; with the alternate inclinations such a distinction is provided on both faces of the web. There may well be still other advantages and classes of advantage.

The apparatus shown in FIGURES 1 through 8 and above described is specifically appropriate to the production of a web having nine (two marginal and seven other) longitudinal bands 111; it will however be of course understood that by suitable formation of the knives and choice of the width of the sheet of foil that number may be increased at will, and may be decreased to any number as low as two without destroying the web nature of the resulting product. The last-mentioned variation is illustrated by the Web lllll of FIGURE 11, which also illustrates the obvious variability of inter-band distance by showing such a distance materially larger than in the case of the web of earlier figures.

While I have disclosed my invention in terms of particular apparatus, and as applied to the production of particular products, it will be understood that I intend thereby no unnecessary limitations. Further, it will be understood that by the use of particular terms I do not intend unnecessarily narrow meanings; in referring to a backand-forth movement by the term reciprocate and its derivatives, for example, I do not imply that such movement must be rectilinean Modifications in many respects will be suggested by my disclosure to those skilled in the art, and such modifications will not necessarily constitute departures from the spirit of the invention or from its scope, which I undertake to define in the following claims.

I claim:

1. Apparatus for operating upon a sheet of foil, comprising a surface provided with a thin orifice of length accommodating the width of a sheet of foil to be fed through the orifice, a pair of knives on respectively opposite sides of the orifice, each knife having a respective cutting edge directed toward but permanently out of cutting relationship to the other-knife cutting edge and in contact with said surface, reciprocating means to which the knives are coupled for effecting intermittent and alternate to-and-fro excursions of said cutting edges across the orifice, and continuous-feed means effective on the sheet of foil in advance of the orifice to cause the progressive emergence of the sheet from the orifice throughout the time intervals between the successive said cutting-edge excursions.

2. The subject matter claimed in claim 1 wherein during each said cutting-edge excursion the respective knife temporarily blocks the emergence of the sheet of foil from the orifice and temporarily causes slight flexing of the sheet within the distance from said continuous-feed means to the orifice.

3. The subject matter claimed in claim 1 further including sheet-guiding means in relatively close spaced relation to each of the two surfaces of the sheet substantially throughout the distance from said continuous-feed means to said orifice.

4. The subject matter claimed in claim 1 wherein each of said knives at and closely adjacent its respective cutting areaseo I l. l a edge is provided with at least one recess subdividing its cutting edge into a plurality of spaced sections, the respective sections of the two knives being in alignment with each other as viewed in the direction of knife reciprocation.

5. The subject matter claimed in claim 1 wherein each of said cutting-edge excursions extends at its peak at least slightly beyond said orifice.

6. The subject matter claimed in claim 5 wherein the stroke of said reciprocating means is large relative to the distance by which said cutting-edge excursions extend beyond the orifice.

7. The subject matter claimed in claim 1 further including a carriage which is connected with said reciprocating means and is thereby reciprocated along said surface and in which each of said knives is mounted thereby to be coupled to said reciprocating means.

8. The subject matter claimed in claim 7 wherein said carriage'is free of contact with said surface and wherein said knives are mounted in the carriage for movement relative thereto in a direction generally normal to said surface, further including means biasing the knives rela tive to the carriage and against said surface.

9. Apparatus for operating upon a sheet of foil, comprising a surface provided with a thin orifice of length accommodating the width of a sheet of foil to be fed through the orifice, a knife adjacent the orifice and having a cutting edge extending along the orifice, a carriage reciprocable transversely of the orifice along but out of contact with said surface, said knife being mounted in the carriage for movement relative thereto in a direction generally normal to said surface, means biasing the knife relative to the carriage to maintain said cutting edge in contact with said surface, reciprocating means to which the carriage is coupled for efiecting intermittent to-and-fro excursions of said cutting edge across the orifice, and continuous-feed means efiective on the sheet of foil in advance of the orifice to cause the progressive emergence of the sheet from the orifice between successive such cutting-edge excursions.

10. Apparatus for operating upon a sheet of foil, comprising a surface provided with a thin orifice of length accommodating the width of a sheet of foil to be fed through the orifice, a knife adjacent the orifice and'having a cutting edge extending along the orifice and in contact with said surface, reciprocating means to which the knife is coupled for effecting intermittent to-and-fro excursions of said cutting edge across the orifice, continuous-feed means effective on the sheet of foil in advance of the orifice to cause the progressive emergence of the sheet from the orifice between successive such cutting-edge excursions, and sheet-guiding means in relatively close spaced relation to each of the two surfaces of said sheet substantially throughout the distance from said continuous-feed means to the orifice.

11. The subject matter claimed in claim 10 wherein during each said cutting-edge excursion the knife temporarily blocks the emergence of the sheet of foil from the orifice and temporarily causes slight flexing of the sheet within the distance from said continuous-feed means to the orifice.

12. The subject matter claimed in claim 10 wherein each of said cutting-edge excursions extends at its peak slightly beyond said orifice and wherein the stroke of said reciprocating means islarge relative to the distance of such extension.

References (Jilted by the Examiner UNITED STATES PATENTS 604,150 5/98 Hoberg 83-595 7 87,970 4/ 05 Zimmerman 83-169 890,300 6/08 Reinhold 83582 999,372 8/ 1 1 Kempster 83440 1,759,025 5/30 Sutherland 83-578 2,908,329 10/59 Powell 83355 FOREIGN PATENTS 560,235 7/58 Canada.

481,766 8/29 Germany.

675,759 5/39 Germany.

ANDREW R. JUHASZ, Primary Examiner.