US2405885A

US2405885A - Yarn tensioning device

Info

Publication number: US2405885A
Application number: US578031A
Authority: US
Inventors: Eugene C Gwaltney; Henry R Marsh
Original assignee: Saco Lowell Shops
Current assignee: Saco Lowell Shops
Priority date: 1945-02-15
Filing date: 1945-02-15
Publication date: 1946-08-13
Anticipated expiration: 1963-08-13

Description

13, E. c'. GWALTNEY E'F AL 2,405,885

YARN TENSIONING DEVICE Filed Feb. 15, 1945 Patented Aug. 13, 1946 2,405,885 YARN TENSIONING DEVICE Eugene C. Gwaltney, Biddeford, and Henry R. Marsh, Saco, Maine, assignors to Saco-Lowell Shops, Boston, Mass., at corporation-of Maine Application February 15, 1945, Serial 'No. 578,031 I 8 Claims.

This invention relates to devices for applying a tension or drag to a travelling yarn or thread. Such devices are commonly used in a considerable variety of textile machinery and the present invention is directed more especially to the requirements of those articles of this character in which an exceptionally uniform degree of tension must be maintained, and in which also a very accurate adjustment of the degree of tension is necessary.

For example, these requirements are extremely important in twisting machines of the so-oalled 2 for 1 type. In them the yarn is drawn from a supply body, usually stationary, and customarily is guided through that body along its axis to a flier revolving around said axis. From the eye of the flier the yarn is fed to a stationary guide eye, usually located above and in line with said body, and then passes to a wind-up mechanism. When the flier is run at high speeds the balloon formed between the flier and the stationary guide eye tends to become excessive and a, very accurate control of the tension between the supply body and the flier is essential in controlling the size of the balloon.

The present invention aims to devise a tension device which will satisfy these requirements, which can be manufactured economically, will be exceptionally reliable in operation, and which can be quickly removed from the machine and taken apart when necessary for any purpose as, for example, to remove accumulations of lint and fly.

The nature of the invention will be readily understood from the following description when read in connection with the accompanying drawing, and the novel features will be particularly pointed out in the appended claims.

In the drawing,

' Fig. 1 is a side elevation of a tension device embodying this invention;

Fig. 2 is a front elevation of the device shown in Fig. 1;

Fig. 3 is a vertical, axial, sectional view of said device, with some of the parts shown in elevation; and

Figs. 4 and 5 are transverse, sectional views, considerably enlarged, taken on the lines 6-4 and 5-5, respectively, of Fig. 3.

The construction shown in the drawing comprises a tubular body, indicated in general at 2, provided at one side with a recess and having tubular yarn guiding sections, indicated at a and b, respectively, above and below said'recess In 2 t are mounted, the lower plate'having an approximately fiat body portion with down-turned or flanged ends 3'3', resting on horizontal shoulders'55 atthe opposite ends of the recess. The other plate 4 is similar to it but is provided with up-turned sides extending longitudinally of it and also with flanged ends 6 and I. These plates have smooth fiat meeting surfaces.

Pressure is applied to the plates by a spring 8 of the leaf type and which preferably consists simply of a length of spring wire, suitably bent, as will be described. It is held in place by providing it-with an inturned tip 0, Fig. 3,

at its upper end, which extends into a hole provided in the shank or tubular extension at of the body 2, and it is clamped there by a set screw iii threadedthrough the base of a cap l2 mounted on the upper end of said shank. This shank also is flattened on one side, as shown at a in Figs. 2 and 4, and the flattened surface is grooved longitudinally to receive said spring. Below the shank the spring passes through a radial slot i3, Figs. 8 and 4, formed in a flanged section 2 of the body 2, and then through slots in the two end flanges 6 and l of the upper plate -l. Between these points the spring is provided with an inwardly bent portion or knee (1 which bears on the upper tension plate 4, and at its lower end it has a reversely curved section e, Fig. 3, which rides in a slot 1 formed partly in the lower extension I) of the body 2 and partly in a yarn guiding bushing H3 secured in said ex tension by a set screw l i.

The particular tension device here shown is intended to fit into the upper end of the tubular section 8 of the yarn carrier shown in pending application Ser. No. 495,832, filed July 23, 1943, (now issued as Patent No. 2,374,085) and to take the place of the tension device illustrated in that application. As the yarn is drawn from the supply body surrounding said tubular section, it enters the eye g, Fig. 3, of the cap l2, and travels down through the tubular shank a,

through the bore of the yarn guiding bushing H3 at the lower end of said shank, passes between the tension plates 3 and l, and out through the small bore of the lower yarn guiding bushing M. It will be observed that these bushings l4 and l 55 are in axial alignment with each other and with the yarn tube a and the eye 9. Also, that this axis is in line with the flat meeting surfaces of the two tension plates 3 and l. Above the tubular guiding section of the shank a, this member is enlarged somewhat to receive a body of said recess lower and upper tension plates 3 and felt 2d, or

other fibrous material, which bears lightly on the yarn but with enough pressure to apply a resistance sufficient to straighten out any loops or kinks that may be in it. Consequently, the yarn travels freely through the entire body of the tension device except for the very light drag applied to its at 20 and the main resistance to its movement applied by the two tension plates. The part 26 is really a pre-tension element which ensures the straightening of the yarn before it passes between the tension plates 3 and 4.

In order to adjust this tension with a high degree of accuracy, an annular slide or ringlB encircles the shank a and carries a set screw l1 which may be tightened up to clamp the spring firmly to the shank. At the side of the ring opposite the set screw a pin I 8 passes radially through it and is fixed in it, the inner projecting end of this pin, as shown in Fig. 3, riding in a groove formed longitudinally in the shank face a where it prevents any rotative movement of the slide on the shank. Thus the screw l! is always held directly over the spring 8 in all positions of adjustment of the slide lengthwise of the spring.

Both tension plates are held in place by the spring 3. The upper one may be slipped out of it operative position merely by pressing down- Wardly on one of its lateral flanges, thus causing it to rotate around the spring 8 and to tip out of place. If, then, the lower plate is lifted at one corner, it will also tip around the knee d and swing to one side of the recess where it may be lifted out. Both plates may be returned to their operative positions by a reversal of the operations just described. I

From the foregoing it will be evident that the active length of the spring 8 utilized in applying pressure to the tension platelil is that between the knee d and the set screw ll. 'Also, that this length can be adjusted accurately by the arrangement above described, and that the gradation of pressure can be made very gradual. These are highly desirable results, particularly when the device is used in a twister of the 2 for 1 type. While the slide alone is effective up to a certain degree to adjust the active length of the spring, there is a tendency, when the slide alone is used, for the spring to bow outwardly above the slide, and this action reduces the accuracy of the adjustment. However, when the set screw H i tightened up, it clamps the spring securely to the body, thus increasing very substantially the clamping pressure exerted by the slide itself. This arrangement has been found highly effective.

Preferably the intermediate section 2 of the tension body is grooved to receive a soft rubber bushing 2i, somewhat larger in outside diameter than the other parts of said body, so that it engages the inner surface' of the central tubular member 8 of the carrier shown in the patent above referred to and provides a yielding contact with the bore of said member. This bushing has been omitted from Figs. 4 and 5.

Preferably, also, the upper adjacent surfaces of the plates are slightly bevelled or grooved to form a short funnel section, as indicated at h in Fig. 5, to assist in guiding the wire customarily used in threading up the tension device.

The capl2 may be made of any convenient material such, for example, as one of the molded plastics, and it is releasably secured on the body 2 by the set screw I ll.

From the foregoing it will be evident that the invention provides a very simple and compact, but rugged and substantial, form of tension de- 4 vice in which those factors controlling the degree of tension applied to the yarn are capable of very accurate adjustment.

At the same time the tension plates can be quickly removed for cleaning and replaced. The same also is true of the cap 12 and the pre-tension device 20 mounted in it.

While we have herein shown and described a preferred emodiment of our invention, it will be evident that the invention may be embodied in other forms without departing from the spirit or scope thereof.

Having thus described our invention, what we desire to claim as new is:

1. A yarn tension device comprising a supporting body through which the yarn is guided, plates supported in said body for pressing the yarn between them as it passes through said body, a leaf spring pressing said plates together, said spring extending in a direction generally parallel to said plates and means for adjusting the pressure so exerted on the yarn comprising a slide bearing against said spring and mounted on said body for adjustment lengthwise of the spring.

2. A yarn tension device comprising a supporting body through which the yarn is guided, plates supported in said body for pressing the yarn be tween them as it passes through said body, a leaf spring pressing said plates together, means for adjusting the pressure so exerted on the yarn comprising a slide bearing against said spring and mounted on said body for adjustment lengthwise of the spring, and means cooperating with said spring to increase the pressure applied to the spring by the slide itself.

3. A yarn tension device comprising a supporting body through which the yarn is guided, plates supported in said body for pressing the yarn between them as it passes through said body, a leaf spring pressing said plates together, said spring extending in a direction generally parallel to said plates andmeans for adjusting the pressure so exerted on the yarn comprising a slide bearing against said spring and mounted on said body for adjustment lengthwise of the spring, and screw-threaded means cooperating with said slide to clamp the spring to said body in any position of adjustment of said slide.

4. A yarn tension device comprising a supporting body through which the yarn is guided, plates supported in said body for pressin th yarn between them as it passes through said body, a leaf spring pressing said plates together, means for adjusting the pressure so exerted on the yarn, comprising a slide embracing a portion of said body and disposed transversely thereof but mounted to slide longitudinally of said body, and a device carried by said slide and riding on said spring and adjustable relatively thereto to clamp the spring against said body.

5. A yarn tension device comprising a supporting body through which the yarn is guided, plates supported in said body for pressing the yarn between them as it passes through said body, a leaf spring pressing said plates together, means for adjusting the pressure so exerted on the yarn, comprising a slide embracing a portion of said body and disposed transversely thereof but mounted to slide longitudinally of said body, and a set screw threaded into a portion of said slide and positioned to bear on said spring, said screw being adjustable to clamp the spring against said body.

6. A yarn tension device comprising a supporting body provided with a'lateralopen-sided recess and with a tubular yarn guiding shank, two opposed plates mounted in said recess to grip the yarn between them as it travels through said body, a leaf spring having a portion extending along said shank and another portion bearing on one of said plates to press them together, and a slide mounted on said shank to engage said spring and adjustable to vary the length of said spring efiective to apply pressure to said yarn.

'7. A yarn tension device according to preceding claim 6, in which said slide carries a set screw to bear on said spring, and means cooperating with said slide to guide it during its adjusting movement to maintain said set screw in position to bear on said spring at any point in its range of adjustment.

8. A yarn tension device comprising a supporting body provided with a lateral open-sided recess and with a tubular yarn guiding shank, two opposed plates mounted in said recess to grip the yarn between them as it travels through said body, said plates having fiat, smooth-meeting surfaces and oppositely directed flanges, a leaf spring mounted at one end on said shank and having a free portion extending along said shank and overlying said plates, said spring having a knee bearing on one of said plates to press it against the other, and a slide encircling a portion of said shank and overlying said spring, whereby the slide is adjustable to vary the length of said spring effective to press said plates together.

EUGENE C. GWALTNEY. HENRY R. MARSH.