US2430944A - False twist tube for use in preparatory and spinning machines - Google Patents

Description

Nbv, 18,1947. J. NOGUERA 294309944 'FALSE TWIST TUBE FOR USE IN PREPARATORY AND SPINNING MACHINES Filed March 29, 1946 2 Sheets-Sheet 1 20 K 1 6 5. 4 Mme A07 j 4 /-10- sj f fi ;/2 j/ g E 2 lA/VEA/T'OR 14 TMRNEYS J. NOGUERA Nam-18, 15947.

FALSE TWIST TUBE FOR USE IN PREPARA'I'ORY AND SPINNING MACHINES Filed March-29, 1946 2 Sheets-Sheet 2 M/I/E/VTOR JOfifPH waaaeen ax MM M HTRLQNEKS Patented Nov; 18, 1947 FALSE TWIST TUBE FOR USE IN PREPARA- TORY AND SPINNING MACHINES Joseph Noguera, Manchester, England, assignor to Casablancas High Draft Company Limited, Manchester, England, a British company Application March 29, 1946, Serial No. 658,136 In Great Britain April 13, 1945 '1 Claims. (01. 57-128) This invention relates to false twist tubes for use in certain preparatory and spinning machines, more particularly in compound drafting machines wherein the tube is mounted between two consecutive drafting arrangements. The purpose of the false twist tube is to twist the strand as it passes from one drafting arrangement tothe next, the material being usually subjected to a certain amount'of draft while receiv ing the false twist from the tube.

There are two common types of false twist tube. According to the first, a nip is formed on the material as it passes between the two co-opcrating prongs of a spring, or between a spring and a fixed part of the tube, while according to the second, the twist is imparted to the material by causing it to follow a zig-zag path. The in vention is concerned with the second type of tube which has the advantage, inter alia, of being easier to thread.

The necessary zig-zag path is usually given to the strand by )causing it to pass through an inclined groove formed in a head located a short distance away from the exit end of the tube, the two parts of said zig-zag path thus consisting of the inclined groove and the path between the forward end of said groove and the exit of the tube. The material is therefore caused to crank about the forward end of said slot and the, amount of twist imparted to the strand depends upon the extent of this-cranking action. It will sufficiently twisted and therefore slack will be less intensely twisted.

The present invention seeks to provide a false twist tube of the kind described wherein the intensity of the twisting action is inversely proportional to the tension of the strand, and which will impart a uniform amount of twist to strands of widely different thicknesses.

In accordance with the invention there is provided a false twist tube wherein an abutment is provided over which a strand passes in proceeding towards the outlet of the tube, and wherein means is arranged to bear .resiliently upon the strand ata point intermediate the abutment and the outlet of the tube whereby the strand is caused to follow an appropriate zig-zag path.

For a better understanding of the nature of the Figure 1 is a longitudinal section through a known type of false twist tube.

Figures 2 and 3 are sectional details of the false twist tube shown in Fig. 1, with strands of different thicknesses shown therein.

Figure 4 is a longitudinal section through a r false twist tube produced in accordance with the would be very inconvenient. Another disadvantage of this type of tube is that the efiiciency of the twisting action is directly proportional to the tension of the strand, with the result that strands which have already become slightly over- Y invention.

Figure 5 is an end view of the tube shown in Figure 4.

Figure 6 is a side elevation of a detail of one end of the tube shown in Figure 4',v and Figures '7, 8 and 9 are sectional details of the tube shown in Figure 4, with various thicknesses of strand shown in their working positions.

Referring first to the known false twist tube shown inFigs. 1 to 3 it will be observed that the tube essentially comprises a body I of hollow cylindrical form provided with an internal transverse guide portion 2. There is an inclined guideway 3 therein which is adapted to lead a strand 4 in zig-zag fashion towards the outlet 5. In use the false twist tube is rotated about its axis and the strand 4 therein has a twist imparted to it. Figs. 2 and 3 show the same false twist tube as in Fig. 1 when threaded with strands of different diameters. It is clear that the thick strand 6 of Fig. 2 bears upon the inclined guideway at points A and B and also at the point C p upon the outlet. Similarly, the thin strand 1 and exerts a pressure thereon which will be substantially the same as the pressure exerted on the thinner strand 22 of Fig. 8, because the leaf spring I4 is of relatively great length and the extra deflection involved will not noticeably increase the reaction tension. in the spring. In

both Figs. 7 and ,8 the strands 2i and 22 are fairly taut indicating that no greatdegree of appreciated that with the known false twist tubes their effectiveness will depend to some extent upon the diameters of the strands threaded therein. It will also be appreciated that the effect of the known false twist tubes will be undesirable with regard to varying tensions in a strand. Thus for example in the case of the strand 1 of Fig. 3, when the strand is relatively slack and does therefore require to be further twisted, in fact the amount of twist imparted thereto will be less than that which would have been imparted if the strand had been tauter. On the other hand when the strand 1 is very taut due to over-twisting the tendency will be to impart yet further twist to the strand.

Referring now to Figs. 4 to 9 of the drawings, it will be seen that the false twist tube of the invention is generally of the same external appearance as the known tube, comprising a cylindrical body 10 with an outlet ll. Within the hollow of the cylindrical body I0 there is an abutment i2 (Figs. 4, 5 and 6) over which the strand l3 passes. The abutment I! has a transverse linear face working against the strand i3 but there is a central recess which locates the strand.-

The strand isheld in contact with the abutment l2 by a leaf-spring l4 secured as at l5 to the internal walls of the cylindrical member ID. As will be seen from Fig. 4, the free end of the leaf spring i4 is cranked and is turned back on itself as at IE to form a smooth working edge for contact with the strand i3. From Figs. 5 and 6 it will be observed that the outlet end of the tubular member ID is on either side formed with cut-out portions i1 and i8 through which the working end of the leaf spring l4 projects. The cut-out portion l1 opens into a longitudinal passageway ITA formed in the side of the cylindrical body member i0, and opens also, by means of a passage l9, into the feed outlet ll. As indicated in Fig. 5, the longitudinal passageway I'IA passes obliquely as at "B through the rim 20 formed externally upon the cylindrical body member Hi. It will be noted from Fig. 5 that the free end iii of the spring I! flares outwardly towards the extremity thereof and such extremity is bent so that a concave surface is presented to the strand l3 when the same is contacted by the spring. 7

It is a matter of extreme simplicity to thread a strand into the false twist tube described above, since whilst the tube is held in the left hand. a finger of the left hand may be employed to raise the leaf spring away from the abutment II. The strand may then be entered into the slot HB and from thence into the leadway l9 and into the outlet ll itself. In bringing the strand to the outlet it is passed between the end of the raised leaf spring and the abutment l2 so that when the spring is released it will assume the position indicated in Fig. 4 with reference to the strand.

Figures 7, 8 and 9 show various thicknesses of strand in a false twist tube of the invention. In Fig. 7 it will be observed that the strand II is of relatively great diameter. The leaf spring I adjusts itself to accommodate the strand 2i twist should be imparted to them. It will be observed that in both cases the degree of cranking.

of the strand produced by the spring blade I is not very great. This may be seen by comparison with Fig. 9 where it is supposed that a" medium size strand 2! is being dealt with, this strand being somewhat more slack. Because the tension is not so great in the strand 2! it is bent to a much greater extent out of line and accordingly increased twist is imparted thereto tending to increase the tension in the strand. In this way the desired control of the strand is obtained.

It hasbeen indicated above that the degree of cranking imparted to a strand determines the twist imparted thereto. The expression degree of cranking" is to be read as referring not only to the variation of the crank radius but also to the variation of the angle of the zig-zag path followed by a strand. Thus a greater degree of cranking and hence a more effective impartation of twist could be obtained by causing a strand to follow a sharper zig-zag path whilst maintaining the same crank radius.

I claim:

1. A false twist device for use in preparatory and spinning machines for textile fibres comprising a false twist tube, an inlet and outlet respectively at opposite ends of said tube, an abutment within said tube over which the fibre strand passes in proceeding from the inlet towards the out- .false twist device comprising a false twist tube, a

feed inlet and outlet respectively at opposite ends of said tube. a fixed abutment within said tube,

over which the fibre strand passes in proceeding from the inlet towards the outlet. and a spring bearing resiliently upon the strand at a point intermediate said abutment and said tube outlet, whereby the strand is caused to follow a zig-zag path.

3. A false twist device for use in drafting mechanism for textile fibres comprising a false twist tube, through which the fibre strand passes during the drafting process, an inlet and outlet at opposite ends of said tube, an abutment within the tube over which the fibre strand passes in proceeding through the tube. and a leaf spring mounted inside the tube with one end secured adjacent the inlet and with the other end free and bearing resiliently upon the strand at a point intermediate said abutment and said outlet. whereby said strand is caused to follow a zig-zag path.

4. A false twist device as claimed in claim 3 further comprising a bent portion at the free end of the leaf spring extending towards and beyond the inner edge of the abutment.

5. A false twist device for use in preparatory and spinning machines for textile fibres comprising a false twist tube through which the flbre strand passes, said tube having cut-away portions adjacent one end, a feed outlet between said cutaway portions, a feed inlet at the opposite end of the tube, an abutment within said tube o ver which the fibre strand passes in proceeding from the inlet towards the outlet, and a leaf spring mounted within said tube and extending over the greater part of the length of the tube, said spring being attached at one end adjacent said inlet with the other free end partially protruding through said cut-out portions and bearing upon the strand between said abutment and said outlet, said strand being thereby caused to follow a zigzag path.

6. A false twist device as claimed in claim 5 further comprising a longitudinal passageway in one side of the tube into which one of said outout portions opens, said cut-out portion also open- 15 ,7

5 of the leaf spring which presents a smooth work ing edge for contact with the strand.

JOSEPH NOGUERA.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Number I r Strader May 13, 1930

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