US1272818A - Cloth-cutting machine. - Google Patents

Description

1'. LlFSHITZ.

CLOTH CUTTING MACHINE.

APPLICATION FILED APR. 5. I9l8.

1,272,818. Patented July 16, 1918.

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IRVING LIFSHITZ, on NEW YORK, n. Y.

CLOTH-CUTTING- MACHINE.

Specification of Letters Patent.

Patented July 16, 1918.

' Application fi1edApri15, 1918. Serial No. 226,924.

To all whom it may concern Be it known that I, IRVING Lrrsnrrz, a citizen of Russia, and a resident of New York, in the county of New York and State of New York, have invented certain new and useful Improvementsin Cloth-Cutting Machines, of which the fOllOWiDg is a specification.

This invention relates to cloth cutting machines of the reciprocating blade type and resides primarily in the means for sharpening blades. In machines of this character the blade is ordinarily secured at, its upper end to the operating mechanism and is guided in the standard which supports said mechanism'from thebase. The lower end of the blade is free and the range of movement is such that said lower end alternately enters and rises above a slotted throat plate substantially flush with the base. The blade is not only sharpened along its front edge but is also sharpened across at least a part of the lower end. Thus the knife during the downward movement cuts not only with the front edge but with thelower end.

The front edge of theblade may be readilysharpened tothe desired rough cutting or rippin edge without removing the blade from t e machine but the cutting edge across the lower end must be sharpened to a razor edge and it is this art which becomes dulled the most rapidly. an no machine with which I am familiar can this be done. without the delay and trouble incidental to the removal of the blade from the machine.

The main object'of my. invention is to provide a sharpening mechanism particularly desi ed to operate on this. lower end portion of the blade and which may be attached to andpermanently carried by the machine. in such a way as to not in any way interfere with the free normal use of the machine in the cutting of the'cloth. In its preferred embodiment I employ a sharpening mechanism including a pair of. rollers of appro priate material to act as grinders and position them in. the comparatively small space beneath or within the base. As important features of my invention I so mount the grinders and their supporting and adjusting mechanism so that they may be readily removed from the machine at will and may be readily applied to any type of reciprocating blade cloth cutting machine. Means are pros dd whereby th g i ders may e p a d.

and held in inoperative position or released for grinding operation in a very simple manner. The parts may be removed or replaced without the use of any special tools and without requiring the skill of experienced machinists.

' In the accompanying drawing I have illus trated one embodiment of my invention although it will of course be evident that this is to be considered in an illustrative rather than in a limiting sense and that various changes may be made within the scope of the nvention as defined in the appended claims.

In these drawings:

' Figure l is a top plan view of a portion of the base of a machine, the standard and blade being shown in section.

Fig. 2 is a transverse section on the line 22 of Fig. l, on an enlarged scale.

Figs. 3 and a are vertical sections approximately on the lines 3 and 4: respectively of Fig. 1.

Fig. 5 is a top plan view of the grinders and their support removed from the base of the machine.

Figs. 6 and 7 are views of the opposite ends of the parts shown in Fig. 5.

Fig. 8 is a side elevation of the parts shown in Fig. 5, the cover or throat plate be ing shown in dotted lines in partly raised position.

Fig. 9 is a top plan View of the combined cover and throat plate.

Fig. 10 is a side elevation of the part shown in Fig. 9.

Fig; 11 shows one of the grinders and Fig. 12 shows one of the means for applying adjustable resilient pressure to the grinders.

I have illustrated my invention in connection with parts of a common type of cloth cutting machine. This includes a base 20, the sides and rear ortions of which curve downwardly toward the supporting surface. The body has a plurality of anti-friction rollers 21 for supporting the base and the remainder of the machine carried thereby and for facilitatin the forward movement of the machine during the cutting operation. Pivoted or hinged to the front edge of the body is the ordinary apron 22, the front edge of which rests directly upon the supporting surface and guides the base beneath the cloth to be cut. Threaded into an aper. ture in the base is the standard 23. T he portion of this standard above the level the This is also longitudinally. slotted; to formza;

guiding groove 24: for the knife 25. The

knife is mounted to reeiprocatewithin thisgroov e byoperating mechanism supported at the upper end of the standard 23 but which it is not necessary to illustrate. The lower end of the knife or blade is. sharpened not only along. its front cutting edge 26 but also along the front portion of its bottomcutting edge'27' shown particularly in Fig 4.. The blade when in lts downward limiting position occupies substantially the position shown in Fig. 4:, although when raised. it comes some little distance above the upper surface of the base. Set in the basein front of the standard and slotted to receive the knife is what is commonly known as a throat plate 28.v l he side and rear edges of this are preferably slightly higher than the level of the upper surface of the base as shown particularly in Fig. 2 so as-to properly guide the cloth tothe knife preventing its catchingon the front edge of the standard. and aiding in reducingfriction. The parts so far described are those commonly found in cloth cutting. machines of the reciprocating blade type and the details thereof form no portion of my invention except in-combination as hereinafter pointed out.

In carryingout my invention I provide a pair of rollers 30- of such material. that the rubbing engagement of the knife blade therewith will tend tosharpen the. latter. They may be of the same material as ordinary oil stone usedfor sharpening or maybe of any other desired abrasive or sharpening material. These are mounted with their axes parallel to and spaced at equal distances upon opposite sides of the knife blade, and

within the space below the throat plate and above the level of the supporting surface and upon which rests the rollers 21. The polishing or grinding rollers 30 are resiliently pressed toward each other so that when-the knife is raised the two rollers are in direct contact but. asthe knife reaches the lower end of its. movement the cutting edge 27 enters between the two grinding. rollers and presses them apart thereby rubbing-over the surface of each and becoming sharpened.

y In practice, 1 preferably provide a housing creasing as shown particularly in Figs. 5 to 8 inclusive- This is in the form of a rectangular. metal box 31 having oppositely disposed outwardly.extending lugs 32 adapt ed to receivebolts,xscrews,. or the like,'33. threaded intov the under. side of the base and holding the box or casing 31 rigidly and firmly in place. The grinding rollers may be mounted in the box in various different ways. but preferably each roller has reduced journal end. portions 345. as shown particularly in Fig. 11 and these enter in the bayonet slots 35 as shown particularly in Fig. 2. The rollers. after being dropped into the slots are moved toward each other and thereby held" against any upward or downward movement. For pressing the rollers together'l preferably provide suitable springs betweeireachv roller and the adjacent side of the housing. Such springs may be designed in various different ways but in order to readily adjust the tension; thereof I employ two coil springs 36 for each roller. each. springsetting against or being secured; to a curved bearing blade 3.7. for engagement witlrthe roller anda socket. stop 38 threaded in. an aperture in, the. side of the housing. By rotating these threaded stops a greater or, lesser tension may be put on the springs and the rollers held together with greater or lesserv pressure. Ihave not shown these springs. and. their supports in Fig. 2, they being purposely. omitted therefrom to more clearly show the bayonet slots 35.

, The'topof therbox ouhou'singisopen and.

the housing isso. positioneddirectly beneath the throat. plate that the latter may and preferably does serve as a coyer for the housing. f the; grinder r ll rs In. the construction. illustrated, the throat. plate. is secured. toenddireetly supported by the housing and merely fitswithin. the aperture in the base. 'The cover or throat plate 28 is shown; as having. two curved; or hooked projections 39' adjacent to one'end and. a slight groove. adjacentto the other. The. curve 0 hooked projection. 39 may fit into apertures or depressions L0. in.v the endof. the housing nearestto. the standard and the; opposite end of, the housing may" havea spring catch ll for engaging in the groove at the adjacent end-of the. throat, plate to resilientlyretainthe latter in position as shown particularly in Fig. 8. It will of. coursebe understood that the end of the housing nearest to the standard is vertically slotted to receive the knife as is also. the bottom. wall of the housmg.

As it is not either necessary or desirable that the grinders. engage; with the ln ife blade. every time the lattercomes down. in cutting cloth I provide. means for holding the. grlnders spaced apart in inoperative position whenever it is not; necessary to utilize their sharpening functions. A very simple means. ofaccomplishingthis resultconiprises a set screw4c2 threaded through the-bottom of the housing and having a pointed endfor engagement between the two grinder-rolL erfs'. "By lQWQling' this. set screw out of en gagement with the rollers they will. be pressed directl-ytogether by the springs and the; knife will be sharpened duringthe'lower portion of each stroke. By giving'this. set screw a. few turns the pointed end. W111 wedge between the grinder rollers and space them apart so that they will not engage with the knife during reciprocation of the latter and thegrinders will thus be held in inoperative position.

My improved device is very simple and inexpensive in construction and it is so designed that it may be applied to various different makes of machines with. little if any altention in the latter. The throat plates vary somewhat in size and shape in different makes of machines but it is merely necessary to cut through the base an aperture of the proper size to receive the housing of my improved device and to provide a pair of threaded apertures for the attaching screws 33. The device is concealed from view and is beneath and protected from the cloth so that it does not in any way interfere with the free movement of the machine through the-cloth during the cutting operation. Any fine grit which may be produced during the grinding operation falls through. and cannot come in contact with any part of the machine with which the cloth may later engage, thus the cloth is protected against soiling. Any sparks which might result from the use of the device while the blade is in the cloth would either be retained within the housing or would fall through to the table beneath the base and thus there is no liability of the spark setting fire to the cloth. The grinders may be very easily removed and turned end for end when they become worn or the tenslon of the springs may be easily changed, the only tool required being a screw driver and no special mechanical skill being needed. The condition of the grinders may be easily inspected at any time by merely forcing the spring catch 41 out of engagement with the throat plate 28 and lifting the latter. Any excess oil. used on the rollers or the bearing thereof, cannot drip on to the cloth as it is already beneath the level of the base over which the cloth passes. Various other advantages of my improved device and of obvious alterations thereof within the scope of the appended claims will be apparent to those skilled in the art.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

'1. A cloth cutting machine having a reciprocating knife presenting a longitudinally extending cutting side and a transversely extending cutting end and a sharpening member in the path of movement of said knife and with which said transversely extending cutting end may engage during the final operation of its downward stroke.

2. A cloth cutting machine having a reciprocating knife having longitudinally and transversely extending cutting edges and a pair of grinder or sharpener members so positioned that the lower end of the knife may pass therebetween and engage with both during the lower portion of its stroke to sharpen only said transversely extending cutting edge.

3. A. cloth cutting machine having a reciprocating knife sharpened transversely of the lower end thereof and a pair of grinder or sharpener members resiliently pressed together and so'positioned that the lower end of the knife may pass therebetween to separate them and engage with both during the lower portion of its stroke to sharpen only said transverse cutting end.

4:. A cloth cutting machine having a base, a standard rising therefrom, a reciprocating knife, and a sharpener for the latter carried by the base beneath the upper surface of the latter.

5. A cloth cutting machine including a base, a vertically movable reciprocating knife and a pair of grinder members carried by the base beneath the upper surface of the latter for sharpening the lower end of the knife.

6. A cloth cutting machine having a base, a knife having a portion thereof movable therethrough and a pair of grinder memiers secured to the under surface of the base for engaging with opposite sides of the downwardly protruding part of the knife.

7. A cloth cutting machine including a base having a slot through which the cloth cutting member may extend and a pair of sharpener members carried by the base beneath the upper surface of the latter for engaging with said cloth cutting member.

8. A cloth cutting machine having a base, and a pair of sharpening rollers secured thereto beneath the upper surface thereof.

9. A cloth cutting machine including a base having a slot, a pair of sharpening rollers beneath the base on opposite sides of the slot and a knife movable downwardly through said slot between said rollers.

10. In combination, a cloth cutting machine base, a housing secured to the under surface thereof, and a pair of sharpening rollers within said housing.

11. In combination, a cloth cutting machine base, a housing secured to the under surface thereof, and a pair of sharpening rollers within said housing, and resiliently pressed together.

12. In combination, a housing, a pair of sharpening rollers disposed therein and re silently pressed together and means for securing said housing to the base of a cloth. cutting machine.

13. In combination, a housing having a pair of bayonet slots in each end thereof, a pair of rollers having their journals dis posed within said slots and held against upward or downward movement, a pair of springs between each roller the adjacent side of the housing and means for attaching said housing to the base of the cloth cutting machine.

14:. In combination, a housing having a pair of bayonet slots in each end thereof, a pair of rollers having their journals disposed within said slots and held against upward or downward movement, a pair of springs between each roller and the adjacent side of the housing, separate. means for adjusting the tension of said springs, and means for attaching said housing to the base of the cloth cutting machine.

15. In combination, a housing, means for securing the same to the under side of a base of a cloth cutting machine, a pair of sharp ening members within said housing, means for pressing said members toward each other and an ad uStable member secured to one topics of this patent may be obtained for wall of the housing and adapted to enter be.- tween said members for spreading them apart. I

16. In a cloth cutting machine a combination of a base, a sharpening member, a housing for the latter, and a combined housing cover and throat plate.

17 In a cloth cutting machine a combina tion of a base having an aperture therethrough, a housing disposed within said base, a pair of knife sharpening members within said housing, and a throat plate se cured to said: housing and serving as a cover for the latter.

Signed at New York, in the county of New York, and State of New York, this 4th day of April A. D. 1918.

IRVING LIF SHITZ.

Washington, D. G.

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