Feb. 28, ROBERTS TWISTER TENSION ASSEMBLY Filed Aug. .2. 1952 5 7; I 4v I INVENTOR. INGHAM S. ROBERTS 6/2: Arron EY- United States Patent TWISTER TENSION ASSEMBLY Ingham S. Roberts, Ridley Park, Pa., assignor to American Viscose Corporation, Philadelphia, Pa., a corporation of Delaware Application August 2, 1-952, Serial No. 302,358
11 Claims. (Cl. 242-149) This invention relates to yarn or thread twisting machinery such as a two-for-one twister and particularly to devices for controlling yarn or thread tension during a twisting operation.
In a typical two-for-one twisting operation, a strand such as a thread, cord, or yarn is pulled from a supply package through the twister and is wound about the spindle of a package winding machine. More explicitly, untwisted or partially twisted yarn is supplied from a supply package, such as a bobbin, cake, or cheese held in place on the twister by a holder rotatably mounted on the twister spindle but held from rotating during the twisting operation. Yarn is drawn from the nonrotating supply package into one end of the rapidly rotating hollow twister spindle, then withdrawn at another point by a flyer and delivered to a rotating eccentric position. As the spindle is rotated, the yarn which progressively passes between the flyer and an overhead ring guide is acted upon by forces which cause it to follow a spiral path. This spiral path revolves about the axis to form an apparent balloon outline which is usually referred to as a balloon. From the overhead ring guide, the yarn passes to the package winding machine.
It is an object of the present invention to produce a simple inexpensive tension device for receiving a strand from a revolving path whereby tension may be developed within the section of the strand extending between the device and a take-up means with a minimum of pressure applied laterally thereto. It is another object to provide an automatic compensating tension device which acts to lessen or to increase the restraint applied to a strand in response to an increase or decrease respectively, in the draft force applied to the strand. Still another object is to provide a tension device for a twisting machine which inhibits the formation of loops in the yarn in the portion thereof passing into the device and also inhibits the twist from passing backwardly along the running yarn into the portion of the yarn passing through the tension device. Other objects, features, and advantages will be apparent from the following description of the invention and the drawing relating thereto in which Fig. l is a partial section of a two-for-one twister into which is incorporated a tension device constructed in accordance with the present invention;
Fig. 2 is a section of a modified tension device; and.
Pig. 3 is a section of another modified tension device.
The invention, in brief, comprises a tension device which accomplishes the objects of the invention by anarrangement of opposed cooperating faces of 'two members, i. 'e., a lower member having a central passageway and an upper member loosely supported on the lower member with a stem thereof fitting loosely into the passageway. The face of each member is formed with alternately protruding and recessed surfaces which define at least one tongue or ridge and at least one groove or valley,
within a groove formed in the othermember.
2,736,511 Patented Feb. 28, man
a revolving path outside the device along a sinuous path between the faces of the members into the passageway and thus apply tension to the strand as it passes toward a take-up means. One member moves away from the other member in accordance with the tension exerted by the take-up means and thus the members operate to reduce the tension applied by the device in accordance with an increase in tension of the strand exerted by the take-up means.
Fig. 1 illustrates partly in section, a two-for-one twister which comprises, as principal parts, a motor 5, spindle shaft 6, a flyer 7 attached to the shaft, a package holder 8 rotatably supported by the shaft 6, a cover 9 for the package holder, and a yarn tensioning and guiding device supported by a package core 11. A strand package 14 of which the core 11 is a portion, rests upon an annular felt piece 15 positioned on the seating surface of the package holder. The package is centered with respect to the holder 8 by radial fins 17.
The package holder 8 is restrained from rotating by the magnetic relationship between magnets 18, secured to a bottom surface thereof just above the non-magnetic disc element 21 of the flyer and at equal distances from the shaft axis, and the stationary magnets 19 mounted just below the element 21. A strand 24, from the exterior of the package 14, passes between the portions 26, 27 of the tensioning device 25 into and through the passageway 57 and downwardly into the bore of the shaft 6. Through a radial aperture 29 in the shaft 6, the strand 24 passes outwardly of the shaft, then through the eye 31 of the flyer and upwardly through a guide 33 to a take-up means (not shown). As shown, the package support 8 is rotatably mounted with respect to the roller bearings 36 and 37, the outer races of which t within a pair of bushings 39 and 49 secured within a hub member 42 of the package support.
Referring now to the tension device 25, the lower portion 27 thereof is annularly grooved to provide a surface 45 concentric to its axis for centering the member within the core 11 of the package, and a radially extending surface 46 by which the member may seat upon the end surface of the core. The core 11 of the package which supports the tension device is constructed to precise predetermined measurements to provide the proper relationship of the tension device 25 with the other parts of the twister and the core 11.
The portion 27 comprises a supporting member 48, a strand engaging element 49, a wear-ring 50, a nut 51 in threaded relationship with the exterior surface of the tubular portion of the element 49, a washer 52 held between the nut and the lower surface of the member 48, and a guide tube 53 in threaded relationship with a portion of the nut 51. The assembly 27 may be taken apart readily to replace parts such as element 49 which is subject to considerable Wear as a result of strands passing thereover. The element 49 has a face compressing a plurality of protruding and recessed surfaces which define a pair of upwardly-extending tongues or ridges 55 and 56 and a valley or groove therebetween in which the wearring 50 is seated. As shown, the sidewalls of the tongue and the valley are straight in lateral cross section. The top or crown surfaces of the tongues and the bottom surface of the valley are fiat and joined with respective sidewalls by rounded corners. As shown, the side wall of each valley and the adjacent side wall of a tongue projecting into such valley are approximately parallel. The central vertically-extending passageway 57 has an upper por tion larger in diameter than its lower portion, the latter portion serving as a guide for the strand as it passes downwardly into the twister spindle.
comprises a material having a specific gravity such as to give the member a predetermined weight. In arriving at the desired weight, the member 26 may be drilled from the top such as by forming a bore 58, or by cutting off a top portion thereof along a plane normal to its axis to obtain a surface The bore 58 may be utilized, in case additional weight is needed for satisfactory operation of the tension device, to receive inserts of lead or other material. As one satisfactory construction of the tension device, the upper portion 26 thereof may comprise brass with the exterior surface thereof chromeplated to give it a wear-resistant coat or lamina.
Extending downwardly from the lower face of the member 26 is a central stem 62. This lower face of the member 26 includes annular recessed and protruding surfaces concentric to the stem which define a downwardlyextending annular tongue or ridge 62 and grooves or valleys, with the tongue being of such height as to produce clearances between recessed surfaces of the member 2-6 and tongues 64 and 65 of the member 27. The tongues have rounded edges which minimize damage or abrasion to the filaments of the yarn passing thereover. The clearance between the tongue 64 and the adjacent recessed surface of the member 26 is effective in smoothing out the yarn before it passes between the surfaces which supply the primary retarding forces to the yarn, i. e., the upper surface of the wear-ring 50 and the downwardly facing surface of the tongue 62. As twisting occurs in the section of the yarn extending from the tension device downwardly through the twister to the fiyer, the clearance adjacent the tongue 65, including the radially-extending clearance between the top surface of the tongue 65 and the axially-spaced opposing valley surface, prevents the twist from traveling to any great extent backwardly along the yarn to the primary retarding surfaces of the tongue 62 and the ring 50. It is desirable to prevent excessive twisting of the yarn as it passes between these surfaces so as to make the passage of the yarn therebetween smoother and vibration of the upper portion 26 less likely. This action is further aided by the stem 61 of the upper member having a diameter larger than the lower portion of the passageway 57 so that the strand passing between the stem and the surface defining the upper diametrically larger portion of the passageway 57 is forced against the annular rounded shoulder 6'7 within the tubular portion of the element 49 to provide an additional barrier to the travel of the twist, formed by rotation of the spindle 6 relative to the tension device, backwardly along the yarn through the tension device. These barriers to twist transmission also prevent any loops from being formed adjacent the tongue 62. and the ring 59 which might disturb the stability of the upper portion 26 of the tension device.
The stem 61, although of a diameter larger than the lower-end of the passageway 57, is sufficiently smaller in diameter than the upper-end of the passageway so that the portion 26 may move laterally to a position slightly eccentric with respect to the lower portion 27. The passage of the yarn between the upper and lower portions tends to move the upper portion to an eccentric position thereby forming a crescent-shaped opening or clearance between the stem and the side of the passageway for the passage of the strand therethrough toward the twisting spindle. The upper portion describes a nutatory motion as the strand is unwound from the package; the crescentshaped opening proceeds, so to speak, around the interior of the passageway in accordance with the nutatory motion. The package holder 8, the package 14, and the lower portion of the tension device, of course, are held from rotating by operation of magnets 18 and 19.
Fig. 2 illustrates a modification of the tension device shown in Fig. l. The principal differences between this device and the one just described are: (1) the absence in the tension device 70 of a wear-ring, (2) a relationship be tween the stem 71 and the upper portion or member with the passageway of a member 72 of the lower portion of the device suchthat the strand does not necessarily engage a lateral shoulder between the ends of the passageway, and (3) in the disposition of the primary strand-retarding surfaces of the upper and lower portions. In the device 70, the strand passes between and engages the uppermostsurface of the annular tongue 73 of the lower member 72 and the annular recessed surface or groove or valley 74 of the upper portion. Otherwise the devices 25 and '70 have the same general arrangement of recessed and protruding surfaces disposed concentrically and at different radii with respect to the respective axes of the upper and lower portions. Similarly to the embodiment illustrated by Fig. 1, the embodiment of Fig. 2 has a radially-extending clearance 75 between the crown surface of the tongue nearest the central passageway '76 and the opposing valley serving the same purpose as ascribed to the analogous clearance of the earlier described embodiment, i. e., the preventing of twist traveling backwardly along the yarn to the primary strand-retarding surfaces 73 and 74 of the tension device. Another feature in common with the earlier described embodiment is the parallelism between the sidewall of each valley and the adjacent sidewall of the tongue projecting thereinto as shown in Fig. 2.
The device 70 as well as the device 25 operates in accordance with a self-compensating principle, i. e., when tension increases in the portion of the strand extending between the tension device and the flyer, the strand in passing along a path between the tongues of the upper and lower portions tends to form a straighter path and exert a lifting force on the upper portion. As the surface '74 of the upper portion of the device 7% lifts away from the strand, the retardation on the passage of the strand through the device 7% is relieved somewhat and the total tension in the yarn passing toward the ilyer is reduced.
Fig. 3 illustrates a modified device at which may be substituted in the twister illustrated in Fig. l for either of the devices 25 or 749. This device differs from the previously described embodiments in that the lower portion has a single upwardly extending tongue or ridge 81 while the upper member or portion has protruding surfaces which define tongues or ridges 83 and 34 analogous to the two upwardly extending tongues provided on the lower portion of each of the earlier described devices. The operation of the device Eli is substantially similar to that of the device 25, i. e., the major retarding forces are applied to the yarn as it passes between the crown surface of the tongue 81 and a surface at the bottom of the valley or groove 85 between the tongues 83 and 84. As found in the previously described embodiments, the clearances between the upper and lower portions at 86 and 87 inhibit the twisting of the yarn within the section thereof passing between the tongue 81 and the surface 85. The clearance at 88 smooths the yarn before it passes over the tongue 81 and prevents any looped yarn from entering the tension device. As shown in Fig. 3, the sidewalls of the valleys and tongues extend approximately parallel to the axes of respective members and at right angles with respective bottom surfaces or crown surfaces, as the case may be. Thus as found in the other embodiments, the sidewalls of the valleys and the tongues as seen in radial cross section are approximately parallel. The lower portion of the device may comprise, as shown, two concentric elements 89 and 91,.the element 89 comprising a wear-resistant material with the downwardly extending cylindrically-shaped portion thereof extending into a complementary bore of the element 91 in press-fit relationship. The upper-portion of the device may be fabricated from any wear-resistant material or a material that is coated with a wear-resistant substance such as suggested in the description of the device 25.
The tension devices 25, 70, and are hereinbefore described with.:respect to an orientation. in which the loosely supported member is disposed above and rests upon the member having the central passageway to provide the frictional force for retarding the passage of the strand, the member having the central passageway being connected to supporting apparatus, such as a twister, by the overlapping seating relationships with the core of a package as illustrated. In each embodiment a radiallyextending clearance is provided, as shown, between the tongue of one member and the adjacent valley of the other member nearest the axis of the device to prevent the travel of twist backwardly to the primary strand-retarding surfaces. This clearance is, in each embodiment, contiguous with the crescent-shaped axially-extending clearance, hereinbefore described between the stem and the wall of the passageway through the lower member of the respective tension device. The valleys and the the tongues of each device have, with respect to their cross sections, straight sides, and the axially-opposing surfaces of adjacent tongues and valleys are approximately flat. The tongues are smaller than the valleys into which they fit, as hereinbefore explained, to permit nutatory movement of the upper loosely supported member with respect to the lower member.
One or both of the members may be constructed wholly or in part from a magnetized material and the orientation of the device may then be changed substantially or even reversed with respect to the vertical direction. When only one portion of the device comprises a magnetic mate rial, the other portion may comprise, instead of a mag netized material, a magentically-sensitive material. Since the invention is concerned primarily with the character and contour of the surface provided by the tension device, gravitational or magnetic force applied to the loosely supported portion of the device may also be supplemented or supplanted by force applied from an external source in a direction substantially lengthwise of its axis to urge the portions together by means such as a spring or fluid pressure.
While preferred embodiments of the invention have been shown and described, it is to be understood that changes and variations may be made without departing from the spirit and scope of the invention as defined in the appended claims.
I claim: V
1. A tension devicemounted to'receive a strand pass ing from a revolving path comprising a member having a central passageway and alternately recessed and protrud ing annular surfaces in concentric relationship with the axis of the passageway, said surfaces being disposed radi ally outwardly and concentrically with respect to one end of the passageway, and another member having annular alternately recessed and protruding surfaces and a central stem of smaller diameter than the passageway extending in coaxial relation with said surfaces of the latter-named member, the surfaces of at least one member defining an annular tongue extending into an annular groove defined by the surfaces of the other member, the adjacent oppos ing sidewalls of the groove and the tongue being approximately parallel with respect to a radial cross section of the members and disposed in spaced relationship when one member engages the other in coaxial relation, said members having spaced surfaces extending radially from the passageway to provide an annular clearance therebe' tween contiguous with the passageway.
2. A tension device as defined in claim 1 wherein the crown surface of the tongue is flat and the bottom surface of the groove is flat and parallel to said crown surface and wider than the crown surface.
3. A tension device mounted to receive a strand passing from a revolving path comprising a member having a central passageway and an annular face extending radially from, and concentrically about one end of the passageway, the face having an annular groove in concentric relation to the passageway, and another member having an annular face and an axially-extending stern, of smaller diameter than the passageway, extending from the face of the second member in coaxial relation therewith, the face of the second member defining an annular tongue in concentric relation with the stem smaller in general contour than the groove and having a diameter adapting it to fit in the groove, the sidewalls of the tongue and groove being substantially straight and parallel with respect to radial cross sections of the members with the crown surfaces of the tongue and the bottom surface of the groove being parallel and flat, said bottom surface being wider in a radial direction than the opposing crown surface, the sidewalls of the tongue and the groove being spaced when the second member rests on the first member in coaxial relationship therewith to provide uniform clearances therebetween for nutatory motion of the second member relative to the first member, the faces of the members having spaced surfaces extending radially from the passageway to provide a clearance therebetween contiguous with the passageway.
4. A tension device mounted to receive a strand passing from the revolving path comprising a lower member having a central downwardly-extending passageway and concentric upwardly-facing alternately protruding and recessed surfaces, and an upper member having a downwardly-extending stem of smaller diameter than the passageway and downwardly-facing alternately protruding and recessed annular surfaces in concentric relation with the stem, one of said surfaces of one member being arranged and adapted to form a tongue extending toward the other member, said surfaces of the other member forming two radially-spaced tongues with a valley therebetween contoured to receive said first-named tongue, said valley having less depth than the height of the firstnamed tongue measured in an axial direction, the firstnamed tongue extending, when the upper member is supported by the lower member in a position of substantially coaxial relation therewith, into said valley with clearance between the adjacent sidewalls of the tongues, the crown surface of the tongue of the members disposed nearest the passageway and the recessed surface of the other member in opposed relation to such crown surface being spaced when the members are engaged in said position to provide clearance contiguous with the passageway.
5. A tension device mounted to receive a strand pass ing from a revolving path comprising a lower member having a central downwardly-extending passageway and an upwardly-facing radially-extending annular face concentric to the passageway comprising concentric alternatelyprotruding and recessed annular surfaces, and an upper member having a downwardly-extending stem of smaller diameter than the passageway and a downwardlyfacing face comprising alternately-protruding and recessed annular surfaces in concentric relation with the stem, said surfaces of one member being arranged and adapted to form a tongue extending toward the other member, said surfaces of the other member forming two radially-spaced tongues and a valley therebetween disposed for receiving the first-named tongue, said valley having a depth greater than the height of the first-named tongue as measured in an axial direction, said one member having a recessed surface disposed radially outwardly from the tongue thereof for engaging the crown surface of the radially outer tongue of the other member, the entire crown surface of the inner tongue of the latter member having clearance with an opposed surface of said one member adjacent the passageway to provide a clearance contiguous with the passageway when the upper member rests on the lower member, the sidewalls of the first tongue being spaced with respect to the sidewalls of the two latter-named tongues to provide annular clearances therebetween when the members are disposed in coaxial engaged relationship.
6. A tension device as defined in claim 5 wherein the adjacent sidewalls of the tongues are substantially parallel with respect to radial cross sections thereof, and the crown surfaces of the tongues and the surfacesin opposing relation thereto are flat.
7. A tension device mounted to receive strand passing from a revolving path comprising a lower member having a central downwardly-extending passageway and an annular tongue in concentric relation with the passageway protruding from an upwardly-disposed annular face of the member, and an upper member having a central downwardly-extending stem of smaller diameter than the passageway and an annular downwardly-disposed face defining an annular groove in concentric relation with the stem, the groove of the upper member being disposed to receive the tongue of the lower member when the upper member rests in a coaxial position on the lower member, said groove having less depth than the height of the tongue as measured in an axial direction whereby opposing surfaces of the members disposed radially-outwardly and radially-inwardly from the tongue and the groove are supported in spaced relation, the sidewalls of the tongue spaced from the sidewalls of the groove in said position of the upper member.
8. A tension device as defined in claim 7 wherein each sidewall of the groove is substantially straight and parallel with respect to the adjacent sidewalls of the tongue with reference to the radial cross sections of the members.
9. A tension device mounted to receive a strand passing from a revolving path comprising a lower member having a central downwardly-extending passageway and an upwardly-facing annular face concentric to the passageway, said passageway comprising at least two portions of different diameters, one portion having a larger diameter than the adjacent lower portion and being separated therefrom by a rounded circular shoulder, and an upper member having a downwardly-facing annular face and a stern extending downwardly from the face in coaxial relation therewith, the diameter of the stern being smaller than said portion of the passageway having the larger diameter but being at least substantially as large as said lower adjacent portion of the passageway, the faces of the members having alternately protruding and recessed surfaces concentric to respective axes thereof and disposed progressively radially therefrom, the surfaces of one member defining an axially-extending annular tongue, the surfaces of the other member defining an annular groove for receiving said tongue, the groove being larger than the tongue at least in a radial direction to provide clearance along the radially-inner and radially-outer sides of the tongue when the upper member is supported by the lower member in coaxial relationship therewith, said clearances rendering the upper member capable of nutatory movement relative to'the lower member during passage of revolving strand between the members and into the passageway, said members having. annular surfaces extending radially outwardly from the passageway in opposing spaced relation to provide an annular clear ance therebetween contiguous with the passageway.
10. A device for a textile yarn twister comprising a pair of juxtaposed yarn tension elements mounted on the twister to tension a yarn passing axially through the twister, at least one annular ridge on one of said elements, at least two annular ridges on the other of said elements, said last-named ridges defining an annular groove positioned to receive the ridge on the first element, the ridges and groove having substantially straight parallel side walls with predetermined radial clearance therebetween, walls defining a passageway in one of said elements, and a cooperating stern on the other of said elements positioned to fit within the passageway and having a predetermined clearance with the walls thereof, the faces of the elements adjacent the passageway having predetermined clearance.
11. A tension device for use in a yarn twister assembly, said device including a first member having an opening and a first face extending at approximately right angles to the axis of said opening, a second member having a second face, said second member being disposed on said first member with the first and second faces in opposing relationship, one of said first and second faces having an annular ridge, the other of said faces having an annular groove adapted to receive said ridge, said opposing faces being spaced from each other immediately adjacent to said opening to provide therebetween a clearance contiguous'with said opening, said ridge having its sides disposed parallel to the sides of said groove and being of less width than said groove to permit one of said members to move with a nutatory motion relative to the other ofsaid members as a strand is passed between said first and second faces.
References Cited in the file of this patent UNITED STATES PATENTS 2,080,893 Klein May 18, 1937 2,492,581 Kingsbury Dec. 27, 1949 2,571,109 Carter et a1. Oct. 16, 1951 2,590,372 Bley Mar. 25, 1952 FOREIGN PATENTS 186,437 Great Britain Oct. 2, 1922