US1967486A

US1967486A - Bias-cutting machine

Info

Publication number: US1967486A
Application number: US643676A
Authority: US
Inventors: Stephen O Vennewitz
Original assignee: SEXTON Manufacturing Co
Current assignee: SEXTON MANUFACTURING Co
Priority date: 1932-11-21
Filing date: 1932-11-21
Publication date: 1934-07-24
Anticipated expiration: 1951-07-24

Description

July 24, 1934. s v wrrz 1,967,486

BIAS CUTTING MACHINE Filed NOV. 21. 1932 3 Sheets-Shet l I F35 IHVENT'OE 3 4.7 jfe a/ en O Vennem/z,

4 TQENEY July 24, 19 4- s. o. VENNEWITZ BIAS CUTTING MACHINE 3 Sheet-Sheet Filed Nov. 21. 1932 July 24, 1934.

s. o. VENNEWITZ 1,967,486

BIAS CUTT ING MACHINE Filed NOV. 21. 1932 -3 Sheets-Sheet 5 TG F/4E Y Patented July 24, I934 BIAS-CUTTIN G MACHINE Stephen 0. Yennewitz, Fairfield, Ill., assignor to Sexton Manufacturing Company, Fairfield, Ill., a corporation of Illinois Application November 21, 1932, Serial No. 643,676

1'1 Claims. (Cl. 16473) This invention relates to a certain new and useful improvement in bias cutting machines and has for its prime object the provision of a machinefor automatically converting a web of fabric into a continuous bias-cut strip.

My invention has for a further object the provision of a machine for automatically cutting fabric on the bias while the fabric is in motion,

the fabric being folded for providing a doubled l0 strip which is stitched into'tubular form and then altemately and in succession diagonally cut in its opposite walls, the slitted fabric when unfolded having the form of a continuous strip of bias-cut material.

My invention has for a still further object the provision of a machine for automatically cutting bias-strips from continuously moving webs of fabric material stitched in tubular form, the stitching-operation being eifected synchronously with the bias-cutting operation for regulating the fineness of the stitches.

And with the above and other objects in view, my invention resides in the novel features of form, construction, arrangement and combination of parts presently described and pointed out in the claims. V

In the accompanying drawings (three sheets) Figure 1 is a perspective view of a bias-strip cutting machine embodying my invention;

Figure 2 is an enlarged fragmentary partly sectional side elevational view of the machine, taken from the sewing-head or right hand side thereof;

Figure 3 is an enlarged sectional view of the machine, taken approximately along the line 3-3, Figure 2, illustrating the fabric-feeding and bias-cutting mechanisms;

Figure 4 is a fragmentary top-plan view illustrating one of the bias margin-cutting mecha nisms;

Figure 5 is a fragmentary sectional view taken approximately along the line 5-5, Figure 4;

Figure 6 is a fragmentary top-plan view illustrating the other bias margin-cutting mechanism; v

Figure '7 is a side elevational view of the machine parts shown in Figure 6, other portions of the machine being broken away;

' Figure 8 is a fragmentary plan view of the bias cut fabric-tube as it emerges from the machine; and

Figure 9 is a reduced fragmentary plan view of the bias cut strip resulting from and on unfolding of the bias cut tube of Figure 8.

- Referring now more in detail and by reference characters to the drawings, which illustrate a preferred embodiment of my invention, A designates generally a continuous web of doubled preferably woven cloth or other flexible fabric, that is to say, a web of woven or textile fabric overlapped lengthwise, as at a folded margin 1, to 00 include an upper fold or wall 2 and a lower fold or wall 3 with the free margins 4 of the

walls

2, 3, disposed in registration. In practice, the doubled web A is preferably wound into a roll or bolt B, which is mounted on a spindle or mandrel 5, in turn, conveniently removably journaled on a pair of suitable standards 6 upstanding from a floor or other suitable support adjacent a work-bench or table C. Preferably the mandrel 5 is provided with a wheel 7 with which may be frictionally en-. 7o

gaged a brake-shoe 8 for tensioning the web A as occasion may require, the web A being led from the bolt B over a suitable roller 9 rotarily supported on arms 10 projecting obliquely upwardly from the standards 6 and then over the table C to the cutting-machine proper, as best seen in Figure 1.

The table C includes suitable standards 11, and fixed at an end on the table C is an arm 12, whose opposite end extends laterally between the free web-margins 4 for supporting a wall dividso ing core or frame D ,flatwise intermediate the upper and

lower walls

2, 3, of the doubled-web A. The frame D, which is of approximately rectangular shape and in width is substantially equal to the width of the doubled'web, A, is spaced 35 above the table C for both guiding the web A in its passage over the table C and spacing the

walls

2, 3, one from the other for purposes shortly appearing.

Also mounted on the table C, is a sewing-head E of conventional construction, of which it may here merely be said that the head E is suitably driven by a chain and sprocket arrangement 13 from and by a prime-mover or motor 14 supported on an adjacent standard 11, as will be understood from Figure 1. However, in the present instance, and for the purposes of my invention, the usually provided stitch-regulator and feeder mechanism is omitted from the sewinghead E, the stitch regulation and strip-feeding being obtained by other means presently described, and itvwill be observed that the arm 12 is spaced forwardly of the sewing-head 6, whereby, as the web A is drawn through the sewinghead E, the free margins 4 of the doubled web A are engaged by the presser-foot e of the head E, which stitches the web-margins 4 together as by a line of stitching 15, the doubled web A then taking a tubular form and the so-formed tube A then flatwise enveloping the core or web spacing frame D, as best seen in Figure 1.

Supported for rotation in a suitable framework which includes a pair of suitably spaced standards 16, 16', disposed to the rear of the table 0, are parallel horizontally disposed

shafts

17, 18, upon which are arranged opposed upper and lower feed-

rollers

19, 20, respectively, disposed in alignment with, and suitably spaced rearwardly from, the rear margin of the wallspacing frame D for gripping engagement .of the tubular strip A therebetween.

The shafts 1'7, 18, are lengthwise extended through the standard. 16, which is adjacent the sewing-head E, and carry respective similar meshing gears 21, 21', whereby the

rollers

19, 20, are synchronously driven with the same peripheral speed. The shaft 1'7 also carries a gear 22, which meshes with a gear 23 mounted on the adjacent end of a jack-shaft 24 suitably mounted in bearings, as at 25, supported on a framework 26 disposed in the rear of the table C. At its other end, the shaft 24 extends to a point opposite the drive-end of the sewing-head E, the drive-shaft 27' thereof being connected to the shaft 24 by means of a-suitable mechanical connection generally indicated at 28, and as best seen in Figure 2, whereby the

rollers

19, 20, are also driven in synchronism with the sewinghead E.

The

rollers

19, 20, thus engaging the tubularstrip A, draw on the doubled web A for moving or feeding the same to and through the sewinghead E for application of the stitching 15 to the web-margins 4, and it will, therefore, be seen that, by providing pairs of

gears

22, 23, of different relative dimensions or ratios, the peripheral speed of the

rollers

19, 20, may be varied relatively to the speed of operation of the sewing-head E, whereby the character of the stitch 15, produced-by the sewing-head E, may be regulated from a coarse to a fine stitch, as occasion may require.

' F designates a bias cutting mechanism, which includes a guide-rod 29 horizontally supported by and between the

standards

16, 16, over the plane of the tubular-strip A, forwardly of the feed-

rollers

19, 20, and in parallel relation with, and closely to the rear of, the rear transverse margin of the wall-spacing frame or plate D. Slidable on the rod 29 transversely of the machine, is a carriage 30, on which is mounted for oscillation in a vertical plane a cutter-head 31,

and carried by the cutter-head 31 for movement at right angles to the feed of the strip A and preferably along the rear margin of the core or plate D, is a knife or blade 32 having a length for engagement only with the upper strip-wall 2 when in vertically disposed cutting or slitting position, as best seen in Figure 3. The knife 32 has its cutting edge on its right-hand side, reference being made to Figure 3, and as a whole is obliquely disposed on its vertical axis at an angle of 45, more or less, to the center-line of the strip A ,for normal cutting-engagement with the upper wall 2 of the strip A as the latter departs from the frame D, as will presently more fully appear.

Upstanding from the carriage 30, is a yoke 33,

; which loosely embraces an elongated cylindercam 34 fixed on a shaft 35 journaled for rotation in and between the standards 16, '16'.' The yoke 33 is provided with a lug or cam-follower 36 having co-operative engagement alternately with oppositely threaded spiral or helical cam-

grooves

37, 38, suitably formed in the periphery of the cylinder 34 and extending from end to end thereof, the

grooves

37, 38, suitably crossing one another during their traverse of the length of the cylinder 34 and communicating one with the other at the respective opposite ends of the cylinder 34, as best seen in Figure 3.

The shaft 35 projects suitably through the standard 16 and carries a'gear 39, which, through an idler-gear 40, is driven by and with the gear 21. Accordingly, when the lug 36 is engaged with .the cam-groove 37, the carriage 30 and the carried cutter 32 are caused to travel at a uniform speed transversely of the strip A coincidently with longitudinal movement of the strip A past the plane of movement of the knife 32, whereby the latter effects a cut or slit, as at a, at an angle of 45, more or less, to the length of the tube A, in the upper wall 2 thereof, as shown in Figure 8, the cutter 32 moving from left to right when looking in the direction of strip movement and as shown in Figure 3.

Disposed below the plane of the strip A, inopposing relation with respect to-the mechanism F, is a like cutting mechanism F, which includes similarly a knife 32' upstanding from an oscillatory head 31 supported on a carriage 30' slidably mounted on a horizontal guide rod 29. The cutter 32' has its cutting edge on its left-hand side, reference being made to Figure 3, and the cutter .32 as a whole is likewise obliquely disposed on its vertical axis at an angle of 45, more or les, to the center-line of the strip A, though oppositely to the cutter 32, the cutter 32 being normally disposed for engaging the'lower wall 3 of the tubular-strip A.

The carriage 30 similarly carries a depending yoke 33' loosely embracing a cylinder 34' mounted on a shaft 35' journaled for rotation in and between the lower portion of the standards 16, 16', the yoke 33' carrying a lug 36' co-operating with a pair of cam-grooves 37', 38, provided in the periphery of the cylinder 34', and the shaft 35 carrying a gear 39' which is driven. through an idler gear 40, by and with the gear 21' mounted on the roller-shaft 18. Accordingly, when the lug 36 is engaging the cam-groove 37, the carriage 30 and its carried cutter 32' are caused to travel transversely of the tube A coincidently with longitudinal movement of the strip A past the plane of movement of the cutter 32, whereby the latter effects a cut or slit a at an angle of more or less, in the lower wall 3 of the tubular strip A, the cutter 32' then moving from right to left when looking in the direction ofmovement of the strip A, as shown in Figure 3.

Fixed preferably on the cylinder-cam 34 at the so-designated right-hand end thereof, that is to say, adjacent the standard 16, is a radially projecting cam-tooth or lug 41 for intermittent engagement, for purposes presently appearing, with a plunger 42 slidably mounted in and through suitable vertically registering bracket-bearing 43 low, the horizontal axis of the head 31 when for the similar or like parts of the first described the cutter 32 is disposed in vertical strip slitting position, as'best seen in Figure 3. The several parts are so arranged that, as the cutter 32 arrives at the terminus of its strip slitting movement, the p1unger42 is downwardly shifted by the cam-lug -41 and impinges the pin 46' for rotarily actuating the head 31 for disposing the cutter 32 in oblique or non-cutting position, as shown by dot-dash lines I in Figure 3. Meanwhile, the carriage 30 compressively engages a suitable buffer-spring 48 mounted on the rod 29 adjacent the standard 16, which urges the lug 36 to now enter the reverse cam-groove 38 for returning the carriage 30 and its now inoperative cutter 32 to the left-hand side of the machine. As the carriage 30 approaches its left-hand terminal position, the pin 47 of the head 31 engages a concave cam-face 49 on the suitably projecting end of a bracket supported on the adjacent standard 16', whereby the head 31 is reversely rotarily actuated for disposing the cutter 32 again in vertical strip-slitting position, as shown by dot-dash lines II in Figure 3.

Meanwhile, the carriage 30 compressively engages a buffer-spring 51 mounted on the rod 29 adjacent the standard 16, which in like manner urges the lug 36 to now enter the cam-groove 38 for traversing the carriage 30 across the ma chine, the knife 32 then again cutting in the strip A another slit (1 parallel to and from the first slit a, andso on repetitively during operation of the machine, the carriage 30 traveling alternately first to the right and then to the left' in the machine, the knife 32 being in operative position for cutting a slit a in the upper wall 2 of the strip A when the carriage 30 is. shifted in one or right-hand direction across the strip, and the knife 32 being spaced from the strip A or in inoperative non-slitting position when the carriage 30 is shifted in reverse or left-hand direction across the strip for return of the knife 32 to its initial position. During such carriage and cutter movement, the strip A is also traveling at right angles to the movement of the cutter 32. Hence, as the result of such complementary movements, the slits a, a are formed obliquely or diagonally or on a bias through the strip-wall.

Likewise fixed on the cylinder-cam 34' at the so-designated left-hand end thereof, is a tooth 41' for co-operation with aplunger 42' reciprocable in bearings 43' and biased normally downwardly by a spring 44, the plunger 42' carrying a lug 45' for impingement by the cam-tooth 41' on each revolution of the cam 34.

The cutter-head 31' is also provided with pins 46', 47', the pin 46' being engageable by the plunger 42' for rotarily actuating the head 31' as the cutter 32' arrives at the end of its cutting stroke for disposing the cutter 32' in oblique or non-cutting position, the carriage 30' engaging a buffer-spring 48' mounted on the rod 32' adjacent the standard 16' for urging the lug cutting-mechanism F.

The carriages 30, 30', travel across the tubular strip A in unison, that is to say, in the same direction at the same time, the mechanism F being effective for automatically cutting the bias-slits a in the upper wall 2 during movement or travel of the carriage 30 from left to right in the machine, and the mechanism F being effective for automatically cutting the bias-slits a in the lower wall 3 during movement or travel of the carriage 31' from right toleft in the machine.

As will be seen from Figure 3, the cutter or blade 32, at the commencement of its strip-slitting stroke, is by the engagement of the pin 47 with the cam-face 49 disposed in vertical cutting position and remains in such position for cutting a slit a substantially from the folded margin 1 across the tube-wall 2 until the pin 46, at the opposite side of the machine, is engaged by the reciprocated plunger 42, whereupon the cutter 32 is swung into inoperative non-cutting position, such action occurring in such manner that the cutter 32 is lifted from the strip before the slit a is continued to and through the stitched margin 4 of the tube. In like but reverse manner, the cutter 32' effects a slit from adjacent the stitched margin 4 of the tube to, but not through, the opposite folded margin 1 thereof.

Thus there is an uncut portion of the margin 4 between the termination of the slit a and the beginning of a slit a, the former being also spaced a short distance ahead of the latter, due to the movement of the strip A during the interval of time elapsing from the lifting of the knife 32 from the tube A to the engagement of 'the knife 32' therewith. A similar hiatus exists between a slit a and a slit a at the folded margin 1 of the 'tube, as best seen in Figure 6.

' The tube-

walls

2, 3, therefore, remain connected at the marginal portions 1, 4, of the tubular strip A for even travel of the now bias slitted tube A" to and through the feed rolls 19, 20, the cut tube A" being delivered from the

rolls

19, 20, to and upon a rearwardly extending horizontal table 52 supported suitably by and between the standards 16, 16', as best seen in Figures 2 and 5.

For consequently continuously connecting the slits a, a, a pair of mechanisms G, G, are provided, the tube-margin cutting mechanism G being disposed rearwardly of and at the righthand side of the

rolls

19, 20, and including a drive sprocket 53 mounted on the end of the shaft 18, and a pair of verticallyspaced upper I and lower idler or guide sprockets 54; 55, respectively, suitably supported on the standard 16. Over the

sprockets

53, 54, 55, is trained a suitable flexible endless element or chain 56, the upper run thereof from the sprocket 53 to the sprocket'54 having a suitable upward and rearward inclination, and the chain 56 carrying an inwardly presented lug 57' depending from the iii) swinging the lever 60 at its other or inner end downwardly and forwardly across the upper face of the block 59, a suitable spring or other tensional member 61 normally biasing the lever 60 in upwardly swung position, as best seen in Figure 4.

On its upper face, the block 59 is provided with a forwardly and downwardly inclined way 62, in which is reciprocably mounted a plunger 63 suitably, as by a pin-and-slot arrangement 64, connected to the inner end of the lever 60 for actuation of the plunger 63 by and with the lever 60 responsive to engagement of the latter by the chain-lug 5'7. l

At its lower end, the plunger 63 carries a knife 65 directed toward the tube-margin 4, the length of the chain 56 being selected such that, at proper intervals of the operation of the machine, the lever 60 is recurrently actuated for correspondingly shifting the knife 65 in the direction of inclination of the way 62 for penetrating the tube margin 4, the knife 65 passing through the tube-

walls

2, 3, for momentarily residing in a suitable pocket 66 provided in the table 52, as best seen in Figures 4and 5.

As has been said, the termination of a slit a in the top wall 2 is spaced from the margin 4 and likewise from the beginning of the succeeding slit a in the lower wall 3 of the tube A". The knife 65, however, has its cutting edge obliquely disposed or receding from its inside point 67 outwardly and rearwardly, whereby the point 67 of the knife 65 meets the termination of the slit a, and, since the tube moves rearwardly as the knife 65 advances forwardly the receding edge of the knife 65 effects a diagonal cut or continuation of the slit 0. for connecting the same, through the margin 4, with the beginning of the succeeding slit (1', as best seen in Figure 4.

The opposite margin cutting mechanism G is disposed rearwardly of and at the left-hand side of the feed rolls 19, 20, and similarly comprises a drive-sprocket 53 mounted on the adjacent end of the shaft 18, and vertically spaced idler sprockets 54', 55', over which is trained a chain 56', the upper run of which has a suitable rearwardand downward inclination, and the chain 56 carrying an outwardly presented lug 57 upstanding from its upper run, as best seen in Figure 7.

Adjacent the standard 16', the table 52 supports a depending guide-block 59' having its lower face inclined forwardly and upwardly in registration with an opening 68 provided in the table 52, the opening 68 being likewise in registration with the margin 1 of the slit tubular strip A. Pivotally supported on the lower face of the block 59, is a lever 60 having its outer end engageable with the chain-lug 57', the lever 60 being normally biased in non-operative position by a spring 61'.

On its lower face, the block 59 is provided with a way 62', in which is reciprocably mounted a plunger 63 suitably operably connected, as at 64', to the lever 60' and carrying a knife 65' having an oblique cutting edge and an advancing inside point 67', the knife 65' being shiftable in the direction of inclination of the way 62' on actuation of the lever 60" by the chain-lug 57' for penetrating the tube-margin 1 at suitable intervals. Likewise, the knife 65 passes through the tube-walls for momentarily residing in a pocket 66' provided ina member or bracket 69 suitably supported from the table 52 for overhanging the tube-margin 1, substantially in the manner set forth in connection with the mechanism G and as best seen in Figures 6 and 7.

However, on the folded margin 1 of the tube A", it is desired to connect the lower slit a in the lower tube wall 3 with the slit (1 in the upper tube-wall 2. Consequently the knife 65' is brought upwardly against the lower wall 3 of the tube A" for effecting a diagonal cut or continuation of the slit a for connecting the same through the margin 1 with the slit a similarly as described in connecting a slit (1 with a succeeding slit a.

In use and operation, therefore, it will be seen that a suitably folded or doubled web of fabricmaterial A is stitched along its longitudinal margins 4 for forming a tube A, which is then, while in motion through the machine, diagonally cut, as by the series of slits a, a, respectively, alternating in direction in the also respective opposite walls of the tube A, the slitted tube A" being then further operated upon, while also in motion through the machine, for connecting respective slits a, a, to and through the margins 1, 4, of the tube A", the resulting product comprising a helically-cut fabric-tube which may, in any convenient manner not here shown, be unfolded from its tubular form or condition into a continuous strip Af' of diagonally conjoined rhomboidal fabric sections 70 of bias-cut material, as best seen in Figure 9.

I might add that, if desired, the bias slitted fabric-tube A may be Wound while folded on a mandrel, not shown, for subsequent unwinding at such time as it may be desired to unfold the tube A" for obtaining the bias-strip A', which latter may also conveniently be longitudinally divided for the ready formation of socalled bias-tape '11, as suggested in Figure 9.

The machine may be economically operated with little labor and has been found exceedingly efficient in the performance of its intended functions.

It will be understood that changes and modifications in the form, construction, arrangement, and combination of the several parts of the machine may be made and substituted for those herein shown and described without departing from the nature and principle of my invention.

Having thus described by invention, what I claim and desire to secure by Letters Patent 1. In a bias cutting-machine, in combination, means for moving a strip in approximately a flat plane, a carriage reciprocable crosswise of the moving strip, a cutting-blade mounted for movement with, and being also pivotally shiftable relatively to, the carriage, mechanism for reciprocating the carriage and its carried blade, and means for pivotally disposing the blade in operative position for slitt'ng engagement with the moving strip during travel of the carriage in one direction and for disposing the blade into inoperative non-strip slitting position during travel of the carriage in the other direction.

2. In a bias cutting-machine, in combination, means for moving a strip in approximately a fiat plane, a reciprocable carriage, a cutter-head mounted both for movement with and for oscillation on the carriage, a cutting-blade carried by the head, a reciprocable plunger actuable in synchronism with reciprocations of the carriage for oscillation of the head in one direction at one end of carriage travel for endwise disposing the blade for slitting engagement with the moving strip'during travel of the carriage in one direction, and a cam co-operable with the head .for oscillating the same in opposite direction on engagement of the head with the cam at the opposite end of carriage travel for obliquely disposing the blade into inoperative non-strip slitting position during travel of the carriage in the other direction.

3. In a bias cutting-machine, in combination, means for moving a flat double wall strip in ap proximately a fiat plane, a pair of shiftable cutters, and mechanism for reciprocating the cutters crosswise of, and for alternately-in succession disposing the cutters for slitting engagement with respective walls of the moving strip.

4. A bias cutting-machine, in combination, means for moving a tubular strip, cutters disposed for travel on the respective opposite sides of the moving strip, mechanism for reciprocating the cutters crosswise of the moving strip, and means for successively shifting the cutters at respective alternations thereof into and out of position. for slitting engagement with the moving strip.

5. A bias cutting-machine including means for moving in approximately a fiat plane a strip comprising flatwise superposed and marginally connected walls, and mechanism comprising a plurality of shiftable knives successively operable for cutting the superposed strip-walls and their connecting marginal portions While the same are in motion for forming a series ,of connected diagonal slits alternating in direction in the respective walls of the strip.

6. In a bias cutting-machine, means for moving a flattened tube of fabric-material, means for cutting the opposite sides of the moving tube for forming a series of marginally disconnected diagonal slits alternating in direction in the respective walls of the tube, and reciprocable knives disposed for cutting engagement with the respective margins of the moving slitted tube for connecting adjacent ends of opposed diagonal slits.

'7. In a bias cutting-machine, means for moving a flattened tube of fabric material,- means for cutting the opposite sides of the moving tube for forming a series of marginally disconnected diagonal slits alternating in direction in the respective walls of the tube, a pair of reciprocable knives shiftably disposed for cutting engagement with the respective margins of the moving slitted tube for connecting adjacent ends of alternate diagonal slits, and means for actuating said knives in synchronism with the cutting means.

8. In a bias cutting-machine, in combination, means for moving a strip in approximately a flat plane, a shiitable cutter, and mechanism for shifting the cutter during movement of the strip and. in a path disposed crosswise of the path of movement, and limited to a distance less than the width, of the moving strip for slitting the moving strip on a line which terminates short of the opposite margins of the strip.

9. In a bias cutting-machine, in combination, means for moving a double wall strip in approximately a fiat plane, opposed cutters mounted for movement on opposite sides of the strip, and

mechanism for shifting the respective cutters during movement of the strip and in respective paths disposed crosswise of the path of movement, and each limited to a distance less than the Width, of the moving strip for slitting the moving strip on respectivelines which terminate short of the opposite margins of the strip.-

10. A bias cutting-machine including, in commovable cutters for severing the opposite strip-l walls and their marginally connecting-portions, and means for synchronously actuating the cutters for forming a connected series of diagonal slits oppositelydisposed in the respective walls of the moving strip.

11. A bias cutting-machine including, in combination, means for moving a fiat double wall strip in approximately a fiat plane, a plurality of movable cutters, and means for synchronously actuating the cutters for forming a connected series of diagonal slits oppositely disposed in the respective walls of the moving strip, some of said cutters being in opposed relation and mounted for movement on opposite sides and. crosswise of the strip and others of said cutters being endwise reciprocable transversely through the strip.

12. A bias cutting-machine including, in combination, means for moving a fiat double wall strip in approximately a fiat plane, a plurality of movable cutters, and means for synchronously j actuating the cutters for forming a connected series 01 diagonal slits oppositely disposed in the respective walls of the moving strip; some of said cutters being in opposed relation and mounted for limited reciprocatory movement on opposite sides and crosswise of the strip intermediate the opposite margins of the walls thereof and others 01' said cutters being endwise reciprocable transversely through the opposite margins of the strip.

13. In a bias-cutting machine, in combination, 11

means for moving a strip in approximately a flat plane, a shiftable carriage, a cutter mounted for movement with and for oscillation on the carriage, mechanism for reciprocating the carriage for shifting the cutter alternately in opposite movement with andfor oscillation on the carriage, mechanism for reciprocating the carriage for shifting the cutter crosswise of the moving strip, and means for oscillating the cutter relatively to and at the opposite ends of travel of the carriage for disposing the cutter in operative position for slitting engagement with the moving strip during travel of the carriage in one direction and for disposing the cutter into inoperative non-strip slitting position during travel of the I carriage in the other direction.

15. In a bias cutting-machine, in combination,

means for moving a strip in approximately a fiat plane, a shiftable cutter, and mechanism for reciprocating the cutter in the same plane crosswise of the path of travel of the strip and while the strip is in movement for slitting the moving strip 5 on a line which terminates short of the opposite margins of the strip.

16. In a bias cutting-machine, in combination,

means for moving a strip in approximately a fiat plane, a shiftable cutter, and mechanism including a rotary cylindrical cam for reciprocating the cutter in the same plane crosswise of the path of travel of the strip and while the strip is in move- .ment for slitting the moving strip on aline which including a cylindrical cam comprising a, pair of oppositely threaded grooves connected at the respective ends of the cylinder, a carriage for the cutter, a yoke on the carriage engageable with said grooves, and resilient members for biasing the carriage at the respective ends of said grooves for alternate engagement of the yoke with said grooves.

STEPHEN O.VENNEWITZ.