US2446097A

US2446097A - Cutting apparatus

Info

Publication number: US2446097A
Application number: US537030A
Authority: US
Inventors: Seddon C Nelson
Original assignee: American Viscose Corp
Current assignee: Akzo Nobel UK PLC
Priority date: 1944-05-24
Filing date: 1944-05-24
Publication date: 1948-07-27
Anticipated expiration: 1965-07-27

Description

July 27, 1948. s. c. NELSON summe APPARATUS Filed May 24, 1944 INVENTOR.

314., ATTORNEY ultimate characteristics.

Patented July 27, 1948 UN ED STATES PATENT OFFICE y "i 1,440,091

' I cu'rmc APPARATUS Seddon'C. Nelson, Front Royal, -Va., assixnor to American Viscose Corporation, Wilmington,

DeL, a corporationof Delaware Application May 24, 1944, Serial No. 537,030

This invention relates the production of staple fibers of rayon and other synthetic filamentary material and is particularly concerned with a process and apparatus for'treating staple fiber during its manufacture to facilitate its subsequent processing and to improve its In many procedures for cutting continuous filamentary material to staple fibers, a continuous filamentary materialproceeds to the cutting a device as a heavy bundle such as in the form of a rope or tow of approximately circular, elliptical, or rectangular cross-section, frequently containing many thousands of filaments and this bundle is then cut to discontinuous lengths" thereby forming numerous individual bunches or clumps of fibers. These clumps then proceed either to opening, carding, spinning and like processes or to subsequent stages of treatment, such aswashi 18, bleaching, and then to the opening and other at the 8 '(laims. (01. 19'-66) to cutting apparatus for i rugations. serrations, notches and the like. The

' condition through the apparatus of the present invention so that the fibers cutare in a somewhat softened or plastic condition, there is obtained the additional desirable characteristic ofcrimpiness simultaneously with the opening operation so that a subsequent separate s'teprof crimping is unnecessary to better adapt such staple fibers for subsequent textile processes, such 7 as in carding and spinning. In this arrangement, crimping is obtained along with the opening provided the tow is in a wet or somewhat plastic condition at the time of treatment In the drawing, illustrative of the invention, Figure 1 is a plan view of one embodiment of the invention, associated with a staple fiber cutter of the Beria type applying a rotatable mem her for delivering the continuous filamentary tow to the cutting element by centrifugal force.

Figure 2'is aface view of the knife of Figure 1, Figure 3 is an elevation of a second embodiment of the invention, associated with a staple fiber cutter in which the knives are movable, Figure 4 is a face view of'a modified form of .knife,

a side view' of the knife of Figure 4,

Figure 5 is and Figures and 7 are side and face views respectively of another modification.

Figures 1 and 2 show one form of apparatus embodying the invention. As there shown, an obstruction 2' having a serrated surface 31 is arranged upon the back of the knife 4 to receive clumps 5 of staple fibers thrown thereagalnst. As shown, the knife l is employed with a Beria type of staple fiber cutter which normally throws the clumps of fibers cut therefrom, at a fairly high velocity. This cutter comprises a shearof the disk into cutting relationship. with the stationary knife 4 (or a plurality thereof positioned about the periphery of the disk). The serrated surface 3 of the obstruction is arranged in the 'path'of travelof the fiber clumps 5 thrown from the disk 6 so that they are impacted thereupon and splatter acrossv the surface thereof, This splattering'is accentuated by the indentations of the surface so that considerable opening is accomplished thereby. The tow of continuous filamentary material may be in a plastic condition at the time of cutting so that theserrated surface ,3 accomplishes a certain amount of crimping simultaneously with the opening of the clumps.

When the fiber product is in a plastic condition, it may be desirable to assist its removal from the surface 3, which ordinarily would occur readily and rapidly by momentumor gravity, by means of a fluid jet 9 which is shown (Figure 2) above the indented surface of the obstruction with a long orifice adapted to sweep the entire surface.

Figure, 3 shows a modified arrangement in which the obstruction 2a is provided on each of a number of rapidly rotating knives l0 carried by the shaft l I. this form of device, the condented obstruction 2b in which the serrations so in slope back from one side to the other of the knife II. This arrangement has a further advantage of directing the cut fibers downward.

Figures 6 and 7 show a further modification of the obstruction 2c in which the indentations 3c are disposed generally perpendicular to a plane parallel to the blade and shank of the knife ll.

The indented surface of the projection or obstruction may be arranged at various angles other than those shown in the-drawing; Such variation yields somewhat distinct opening characteristics and when a wet filamentary material is being operated upon they provide some variation of crimping characteristics. The form of indentations may be various,,the serrated and stepped modifications shown in the drawing being merely illustrative. The dimensions of the indentations may vary'widely. However. certain dimensions are preferably smaller than particular dimensions of the clumps of staple fibers being cut, dependso ing upon the manner in which the clumps strike the indented surface. For example, in the arrangement of Figures 1 and 2, where the length of the fiber clumps strikes transversely of the serrations, the "pitch of the serrations should 3!! be smaller than the length of the clump, so that a clump bears against a plurality of the serrations. In the arrangement of Figures 6 and 7 where the steps shear oil portions of the clump,

the height of the steps facing the clumps should 40 be smaller than the bundle thickness or diameter so that a plurality of shearings are efiected upon each clump. v

As stated above the operation of the cutting devices of this invention has as its main purpose the opening of the staple fiber clumps when it is performed upon a dry tow so that subsenuent processing can be more efllciently performed upon the product. However, when the invention is applied to the handling of a: wet continuous filaprising a stationary knife having a cutting edge, a member co-operating therewith to guide the leading end of the material into cutting position,

inentary material, it has the function not only of opening the fiber clumps but of crimping the fibers within the clumps. Previous procedures involving the cutting of staple fibers from a continuous filamentary tow in a wet condition ordinarily sent theclu'mps obtained at the cutting step through wet treatment processes, such as washing, bleaching and then drying. It has been found that the application of the devices of this invention to the production of staple fiber from being extremely simple and inexpensive modifica- 7n tions of the knives alone.

While preferred embodiments have been disclosed, the description is intended to be illustrative only, and it is to be understood that changes and variation may be made without departing 76 In this arrangement the 6 from the spirit and scope of the invention as defined by the appended claims.

I claim:

1. A device for cutting continuous filamentary material to fibers of discontinuous lengths comprising a cutting member having a cutting edge, a memberco-operating therewith to guide the leading end of the material into cutting position, means for imparting a high velocity to one of the members relative to the other in a direction gen-- erally transverse of the cutting edge, and a pro- .lection on the cutting member having an indented surface spaced back of the. cutting edge and away projection thereon having an indented surface spaced back of the cutting edge with its indentations disposed to provide longitudinal ridges lying in planes which are generally parallel to the cutting edge, said surface being inclined to face the tion generally transverse of the cutting edge, and

a projection on the knife havingan indented surface spaced back of the cutting edge and away from the guiding member in a direction transverse of the direction of the "cutting edge and arranged to face the leadingend of the material when the latter is near the cutting position so,

that collision of the fibers therewith occurs upon cutting action whereby an opening and crimping action is exerted upon the fibers as they collide.

' 4. A device for cutting continuous filamentary material to fibers of discontinuous lengths commeans for imparting a high velocity to the cooperating member in a direction generally transverse of the cutting edge,'and a projection on the knife having an indented surface spaced back of the cutting edge and away from the guiding member in a direction transverse of the direction of the cutting edge and arranged to face the leading end of the material when the latter is near the cutting position so that collision of the fibers therewith occurs upon cutting action whereby an opening and crimping action is exerted upon the as fibers as they collide.

5. In combination, a centrifugal cutting device having a stationary knife having a cutting edge, a rotary element for feeding a filamentary bundle endwise and outwardly into cutting engagement transverse of the knife, a projection on the back of the knife away from the rotary element having an indented surface spaced back of thecutting edge in a direction transverse of the direction of the cutting edge, said indented surface facing the portion of the bundle fed outwardly of the rotary 6. A device for cutting continuous filamentary material to fibers of discontinuous lengths comprising a cutting member having a cutting edge, a member co-operating therewith to guide the leading end of the material into cutting position, means for imparting a high velocity to one of the members relative to the other in a direction gen erally transverse of the cutting edge, a projection on the cutting member having an indented surface spaced back of the cutting edge and away from the guiding member in a direction transverse of the direction of the cutting edge and arranged to face the leading end of the material when the latter is near the cutting position so that collision of the fibers therewith occurs upon cutting action whereby an opening and crimping action is exerted upon the fibers as they collide, and means for removing fibers from the indented surface.

7. A device for cutting continuous filamentary material to fibers of discontinuous lengths comprising a cutting member having a cutting edge, a member co-operating therewith to guide the I leading end of the material into cutting position,

means for imparting a high velocity to one of the members relative to the other in a direction generally transverse of the cutting edge, a projection on the cutting member having an indented surface spaced back of the cutting edge and away from the guiding member in a direction transverse of the direction of the cutting edge and arranged to'f'ace the leading end of the material when the latter isnear the cutting position so that collision of the fibers therewith occurs upon cutting action whereby an opening and crimping action is exerted upon the fibers as they collide,

and fluid means for blowing fibers from the indented surface.

8. In combination, a centrifugal cutting device having a, stationary knife having a cutting edge, a rotary element for feeding a filamentary bundle 'endwise and outwardly into cutting engagement transverse of the knife, a projection on the back of the knife away from the rotary element having an indented surface spaced back of the cutting edge in a direction transverse of the direction of the cutting edge, said indented surface facing the portion of the bundle fed outwardly of the rotary element, means for rotating the element at high speed to impel the cut fiber bundles against the indented surface of the projection on the back of the knife whereby an opening and crimping action is exerted upon the fibers as they collide, and fluid means for blowing fibers from the indented surface.

SEDDON C. NELSON.

REFERENCES CITED The following references are file of this patent:

UNITED STATES PATENTS of record in the