US2781981A

US2781981A - Positive stop device in winding machines

Info

Publication number: US2781981A
Application number: US404934A
Authority: US
Inventors: Demarche Edmund
Original assignee: Skenandoa Rayon Corp
Current assignee: Skenandoa Rayon Corp
Priority date: 1954-01-19
Filing date: 1954-01-19
Publication date: 1957-02-19
Anticipated expiration: 1974-02-19

Description

Feb. 19, 1957V E. DEMARCHE 2,781,981

' POSITIVE STOP DEVICE IN WINDING MACHINES Original Filed March 15, 1949 I 2 Sheets-Sheet 1 EDMUND DEMARCHE Feb. 19, 1957 E. DEMARCHE 2,781,981

POSITIVE STOP DEVICE IN WINDING MACHINES Original Filed March l5, 1949 2 Sheets-Sheet 2 INVENTOR EDMUND DEMARCHE ATTORNEY United States Patent O POSITIVE STOP DEVICE IN WINDING MACHINES Edmund Demarche, Utica, N. Y., assigrior to Skenandoa Rayon Corporation, Utica, N. Y., a corporation of Delaware Continuation of abandoned application Serial No. 81,556, March 1S, 1949. This application January 19, 1954, Serial No. 404,934

4 Claims. (Cl. 242-37) Still another object of this invention is toprovide anV improved thread tension controlled stop mechanism for cone. winding machines wherein the stop mechanism is actuated by a thread pluck substantially less than that required to break the thread.

A further object of this invention is to provide anV improved thread tension controlled stop mechanism of increased sensitivity so that the number of broken filaments caused in coning will be greatly reduced.

Still another object of this invention is to provide an improved thread tension controlled stop mechanism for cone winding machines which is constructed to be sensitive to' variations in yarn tension so that greater uniformity of yarn tension is maintained during buildaup of the cone.

Other andl further objectsl of this invention will be apparent tothose skilled in the'art to whichit relates from the following specification, claims and drawing.

In accordance with this invention there is' provided- `an improved stop mechanism for cone winding machines, said mechanism being constructed to detect moderate plu'cltingy of the thread and also to detect undesired variations in yarn tension during build-up of the cone.

It hasI been observed that in the operation of the usual stop mechanism employed on cone winding machines, the balance of weightsy in the pivoted arms of the-mecha.- nism is delicate and critical and as a result a tension of perhaps not over 1 gram is adequate to prevent engagement of the stop mechanism. As 'a consequence the mechanism is one that is diicult to maintain in satisfactory operation and furthermore the stop motion will not function to release and halt the winding operation unless` the' release of tension is substantial. In other words the usual stop mechanism will not engage the stop` motion unless the thread is actually broken. Consequently the mechanism does not function when plucking of the thread takes place and as. a result such thread is wound into the cone.

Imperfections in the cake structure frequently caused partial restraint of one or more laments in the thread and the severity of this restraint determines the magnitude. of the force of the pluck. Since the force of only a few grams is adequate to break the lament this pluck-y ing action causes breakage of ilaments thereby reducing the quality ofvthe yarn. This yarn of reduced quality must not be wound into the cone. Hence the stop motion that will operate as a consequence of such a pluck prevents the inclusion of a length of faulty yarn into the cone and in this manner preventsV the plucked yarn from degrading'a substantial value ofyperfect yarn. t

These 'and other features'of this invention will be mor fully set forth in the following specification, claimsv and drawing in which briefly Fig. l is a view in side elevation illustrating a portion of a cone winding machine incorporating this stop mechanism; Fig. 2 is a sectional View taken along the line 2 2 of Fig. l; Fig. 3 is a detailed view in perspective of the pivot engaging member provided to the stop mechanism of this invention; Figs, 4, 5, 6 and 7 are diagrammatic views employed for the purpose of facilitating description of this invention. Figs. 4 and 5 illustrate schematically the thread tension control leverage of the prior art and Figs. 6 and 7 illustrate schematically the path of the thread through the thread tension control leverage of this invention.

Referring to the drawing in detail there is illustrated a portion of a textile winding machine, such as disclosed in U. S. Patent No. 801,941, into which this invention.,

has been incorporated. The main frame 10 of this machine supports a winding spindle 12 and a cam shaft 14 which carries a cam of conventional construction (not shown) that reciprocates a thread guide 16. The thread guide is carried in a traverse frame 18 that is pivoted'.-

on the cam shaft 14 to swing and thereby allow the guide to move away from the winding spindle as a cop is built up thereon. A linkage 20 of conventional design is provided to the machine to apply pressure to the traverse frame 13 toy resist the outward movement of the thread guide 16. A detent 22 is provided on the traverse frame 18 to prevent the pressure applied by the linkage 20 from forcing the guide back toward the spindle. The

detent 22 includes a pressure arm 24 that engages av V-shaped groove in the underface of the latching sector 26. A spring pressed linger lever 26 is attached to the shaft 22 that is fixed to the detent 22 for the purpose of adjusting the pressure of this detent against the sector 26.

The latching sector 26 is pivoted to the machine frame by means of a pivot stud 28. In addition to its function as a bearing for the pressure arm 24, the sector 26 serves as a detent for a starting lever 30. The lever 30 is mounted on'one end of a rock shaft 31 extending generally parallel to the spindle shaft 12. The rock shaft extends to the back of the machine and is connected to suitable driving mechanism, whereby the machine may be clutched to a power driven shaft. A

The operating lever 3i? is spring-biased to an inoperative position, i. e., in a counter-clockwise direction by means of a spring 32, which has one end thereof anchored on the machine frame and the other end thereof anchored on a lever 34, which extends laterally from the operating lever Sti.

To engage the driving clutch, the operating lever 36, and consequently, the rock shaft 31 to which it is attached, are rotated in a clockwise direction, and the lever onthe lug 40u/hen the latter has been released from the shoulder 42. The weighty of the sector 26 maintains the lug 40 and the shoulder 42 in engagement, and when it is desired to stop the machine it is only necessary tov raise the free end of the sector suiciently to release the-v Patented Feb. 19, 1957 .a rock shaft segment 36 and allow the rock shaft 31 to be rotated under the action of the spring 32.

In order to provide for the prompt arrest of the spindle shaft 12 and the'cam shaft 14, there is provided herein a braking device consisting of a brake segment 46, which is pivoted to one end of the rock shaft arm 36, and which is adapted to engage a brake collar 48 fixed to the winding spindle 12.

A stopping leverage 50 including a forwardly extending thread bar 52, an upwardly extending arm 62 and an angularly disposed rearwardly extending trip leg .3d is pro vided to the winding machine in accordance with `this invention. A thread bearing finger 56 disposed at 4substantially `right angles to the thread bar 52 is normally positioned adjacent lo the top of a comb-like tension device 58 and is adapted to bc supported on the thread as it emerges from the tension device 58 and runs to the arm 62 and the

thread guides

16 and 16a. The ytrip leg 54 of the stop lever normally exten-ds rearwardly into the operative orbit of a stepped release cam 60 fixed for rotation to the cam shaft 14. When the thread bar 52 of the stop lever is supported by the thread, the trip leg 54 of the stop lever is disposed adjacent the face of the stepped release cam 60, but `when the thread breaks or the tension thereof is otherwise materially reduced, the weight of the thread bar will rotate the stop lever in a clockwise direction and thereby carry the extremity of the trip leg 54 into engagement with the stepped release cam 60, whereby rotation of the latter eifectively moves the stopping leverage 50 and the associated segment 26 and sector extension 38 upwardly into rock shaft detent releasing position.

In its most specilic structure the stop lever 50 includes a hub 64, by means of which the same may be suspended from the end of the sector 26 in free rocking relation thereto. The hub 64 has angularly disposed

extensions

66 and 68, which form supports for `the stop lever bar, leg and arm. The

extensions

66 and 68 have each formed thereon an

upstanding tiange

70 and 72, respectively, and opposite these flanges are screw-threaded bosses 74 and 76, respectively, for the reception of screws 78 and 80, respectively. The thread bar 52 and the trip leg 54 are adapted to be clamped to the hub by disposing them substantially at right angles to each other between the heads of the clamping screw and the adjacent hub flanges. The thread bar 52 includes an angularly disposed thread-bearing finger 56, which terminates in a slightly inturned end 56a. The hub end of the thread bar 52 is turned outwardly with respect thereto to form a seat 52a, which is adapted to rest against the face of the hub extension 66. An adjustable weight 54a is provided to the leg 54 and :this weight may be moved along `this leg for the purpose of obtaining the desired static balance in the stopping leverage on its pivot 50a. The trip leg 54- has an outer end 54b, which is angularly disposed to lie in the path of the notched cam shaft disk 60. The other end of the leg is inturncd to form a seat 54e adapted to rest against :the hub extension 68. The tension arm 62 has a relatively long angularly disposed portion 62a, against which the ith-read is adapted to rest in its course to the

thread guides

16 and 16a. The portion 62a terminates in an inturned hooked end 62h, which prevents the thread from running ctf the end of the guide. In a preferred structure the tension arm 62 has an inner looped end 62e adapted to embrace the shank of the screw 7S and lie under the head of the screw, thereby clamping the arm in position. The stability of the arm 62 may be further assured by turning its inner end beyond the eye 62e outwardly to em brace the thread bar 52.

The thread 100 is fed upward from a cake or other type supply (not shown) that is positioned below the thread tension-ing device S6, of conventional design, and after emerging from this tensioning device the thread passes over the spacer member 101 that is attached to the frame member 58a of the tension device 53. This spacer member 101 is positioned a short distance from the plate 102 that is held to the top of thc `frame member 58a by means of the machine screw 103 which also fastens the stop E04 to the top of this frame member. Suliicient spacing is provided between the spacer member 101 and the plate 161. so that the thread 100 may pass therethrough.

The horizontal portion 56 of the arm 52 is positioned above the spacer member 101 and parallel thereto. The hook portion of the stop 104 is arched over the bar 56 and the vertical portion of this stop is positioned to limit the counters!ockwise movement of this bar 56.

The thread passing from the tension device 58 upward through the space between the spacer member 101 and the plate 102 subsequently passes under the horizontal arm 56 and upward over the horizontal portion 62a of the arm 62. After passing over the horizontal arm 62a the thread passesv over the thread guide 16 to the guide 16a that feeds it to the cop. Thus the thread 100 in passing from the tension device 58 to the guide 16a functions in the course of this passage to lift the thread bar 56 into a position more or less directly above the spacer member 101. In other words, this force at this point exerted by the thread 100 tends to rotate `the arm 52 in a counterclockwise direction around the pivot 50a. At the same time the thread 100 exerts a pressure on the arm 62a which produces a force tending to rotate arm 62 about the pivot 50a in a clockwise direction inasmuch as the` arm 62 is attached to the hub member 50 a short distance below the pivot 50a. This is an important `feature of this invention as will be more fully discussed hereinafter.

As a result of the opposing forces produced on the

arms

52 and 62 by the thread 100 a rugged leverage stop mechanism construction consisting of the

arms

52, 54 and 62 may be employed. Furthermore, this leverage is so sensitive to variations in tension of the yarn 100 that it will detect plucked yarn and prevent winding of such defective yarn on the cop. Also while the leverage of this invention is extremely sensitive to yarn tension variations it also .requires an addition of substantially heavier weights 54a to the arm 54 with the resulting advantage that vibration of the lever 54 is reduced. The main purpose of the weight 54a is to provide the desired balance of the leverage around the pivot 50a. This balance must be such that the free end of the arm 54 swings into engagement with the cam 60 upon breakage of the thread 100 or a loss of tension therein.

Reference is made to Figures 4, 5, 6 and 7 for the purpose of more fully setting forth the operation of this device. In Figures 4 and 5 there is illustrated diagrammatically a machine that is not provided with the tension arm 62 .and in vthese views the thread 100 passes through the tension device 58 over the spacer member 101 and under the bar 56 to the thread guides 16 and 16a. As the size of :the cop increases as shown in Figure 5 the Ithread guide 16 moves away from the spindle 12 so that the angle between the thread 100 and the length of the arm 52 increases from an angle which was approximately zero as shown in Figure 4 to approximately 24 degrees as shown in Figure 5.

From the foregoing it will be seen that, with the conventional stop mechanism shown in Figures 4 and 5, as the cone builds up on the spindle 12 the angle of contact of the yarn or thread 100 on the bar 56 gradually increases.

Since the speed of the thread gradually increases as the cone builds up because the rotation of the spindle 12 is constant, the friction of the yarn 100 on the bar 56 increases not only because of the increase in yarn speed but also because of the increased angle of contact between the yarn and the bar 56.A As a result of this increased friction the stopping leverage shown in Figures 4 and 5 does not operate in a smooth and positive manner but on the contrary operates in a very jumpy and jittery manner that becomes accentuated as' the cone builds up. This jumpy and jitteryoperation will in extreme cases break filaments in the yarn and produce a defective cone.

This and other defects are` remedied by the present in-` mately 75 degrees.

'ventina` whichv issehematically shown in Figures 6 and 7 Referringto Figures 6 and. 7, as' the yarn cone is built up on the spindle 12 from yan empty cone` as shown in Figure 6 toa full cone as shown in Figure 7 the diameter of ithe cone increases greatly. Infactthe diameter of a full cone is approximatelyve timesv the diameter of an empty cone. Consequently' if the speed of rotation of the spindle I2 is; constant the thread 1`00`being supplied" to a cone approaching. the size of `a fulifcone' is travelling anywhere up 'to five times as fast as the'thread 100 fed to a relatively empty cone.

Asl the cone is built up the speed ofthe thread being wound. on itnot only increases butV the angle of contact of the thread with thethreadguide bar 16 and the arm 62a decreases. The thread contacts the thread guide bar 16 in Figure 6` over asubstantial angle inasmuch as the cone in* thisl view is substantially empty, howeverwhen the coneissubstantially full as* sliown in Figure 7 the contact of the thread with the bar 16 is substantially only tangential. On the other hand, the thread contacting the arm 62a in Figure 6 subtends an arc of approximately 70 degrees whereas the thread contacting the arm 62a in Figure 7 subtends an arc of approxi- As a result as the friction of the thread 100 on the bar 16 and the arm 62a increases because of the increase in the thread speed the angle of contact of the thread with this bar 16 is greatly decreased and the angle of contact on the arm 62a is gradually decreased. At the same time the angle of contact of the thread 100 with the arm 56 is decreased. This results from the fact that the force exerted on the arm 62a by .the thread 100 is composed of two components, one due to the friction of the thread on this arm and the other due to the tension of the thread. The force due to'friction tends to pull the arm 62a with the thread in the direction of motion of the threadand this force tends to rotate the arm counter-clockwise around the pivot 50a. The force due to tension tends to rotate the arm 62a clockwise around the pivot 50a as previously described. As the speed of the yarn is increased by the build-up of the cone the force due to friction becomes substantial compared to the force due to tension and since these forces oppose each other the net result is that the arm 56 is moved practically against the stop 104 when the cone is built up to its maximum or full size. At this stage of the winding operation the contact of the thread with the arm 56 is practically tangential. The bar 62a therefore functions to reduce the friction of the thread on the arm 56 as the cone builds up. As a result the leverage is much more stable in operation when it employs the additional arm 62 and the action of this leverage is substantially free of any jittery motion but is smooth and positive as well as extremely sensitive. The sensitivity of this leverage is attested to by the fact that it will detect plucks in the yarn and will not permit such defective yarn to be wound on the cone but will act iinmediately to stop the winding operation. In other words it is not necessary that the yarn being wound on the device as shown in Figures 6 and 7 actually to break before the winding operation is stopped as is thevcase with the mechanism illustrated in Figures 4 and 5.

This application is a continuation of my application Serial No. 81,556 filed March l5, 1949, now abandoned.

While I have described this invention in detail with respect to a certain embodiment thereof it is not desired to limit this invention to the exact details set forth except insofar as they are defined by the following claims.

I claim:

l. A stop mechanism for thread winding machines comprising a rotatable spindle, a cone on said spindle for lreceiving the thread, a rotatable step cam, a pivoted traverse mechanism for feeding the thread to said cone, and means for stopping rotation of said spindle, said means including a pivoted arm, a thread tension sensing leverage pivoted at the free end of said pivoted arm, said leverfil age comprising` a hub pivoted ,to said arm, arstarmattached to said hub andH extending from the pivot thereof toward said step cam, a second arm attached to said hub and extending from/the pivot thereof downward, a third arm attached to said hubl at a point well below the pivot thereof and extending in a direction substantially opposite to that o f said first arm, the thread being wound; on said cone being, arranged to pass under thefree end portion of said second arm and over the free end portion of said third arm so that the torque produced by a normal unplucked thread on said second arm is opposite to that produced by such thread on saidthird arrn so as to eliminate jumpy and shaky motion of said'thread tension sensingleverage particularlywhen said cone is builtvup and the speed of said thread is increased because of the increased cone diameter. y

2. A stop motion asset forth in claim 1 further comprising a thread guide pivotally supported near the surface of the cone and being adapted to be moved as said cone is built up to make allowance for such build-up, Said thread guide movement being such as to reduce the angle of contact of the thread therewith as the cone is built up and as the speed of the thread being wound is increased so that the thread friction therewith is reduced.

3. A stop mechanism for 4thread Winding machines comprising a rotatable spindle, a cone on said spindle for receiving the thread, a rotatable step cam, a pivoted traverse mechanism for feeding the thread to said cone, a thread guide positioned adjacent to said traverse, and means for stopping rotation of said spindle, said means including a pivoted arm, a thread tension sensing leverage pivoted at the free end of said pivoted arm, said leverage comprising a hub pivoted to said arm, a first arm attached to said hub and extending from the pivot thereof toward said step cam, a second arm attached to said hub and extending from the pivrot thereof downward, a third arm attached to said hub at a point well below the pivot thereof and extending in a direction substantially opposite to that of said first arm, the thread being wound on said cone being arranged to pass under the free end portion of said second arm and 4over the free end portion of said third arm and over said thread guide to said traverse, the thread passing from said second arm to said third arm moving in a substantially vertical direction and making slightly more than tangential contact with said second arm throughout the winding of said cone, said thread guide being pivoted and being moveable with respect to said thid arm so that the arc of Contact of the thread on said thread guide and the arc of contact of the thread on said third arm decreases as the cone is built up and as the speed of the thread increases whereby shaky and jumpy operation of said thread tension sensing leverage is substantially eliminated and said leverage operates in a positive manner to stop the thread winding machine upon substantial reduction in thread tension.

4. A stop mechanism for thread winding machines comprising a rotatable spindle, a cone on said spindle for receiving the thread, a rotatable step cam, a pivoted traverse mechanism for feeding the thread to said cone. a thread guide positioned adjacent to said traverse, and means for stopping rotation of said spindle, said means including a pivoted arm, a thread tension sensing leverage pivoted at the free end of said pivoted arm, said leverage comprising a hub pivoted to said arm, a first arm attached to said hub and extending from the pivot thereof toward said step cam, a second arm attached to said hub and extending from the pivot thereof downward, a third arm attached to said hub at a point well below the pi'vot thereof and extending in a direction substantially opposite to that of said first arm, the thread being wound on said cone being arrangedfto pass under the free end portion of said second arm and over the free end portion of said third arm and over said thread guide to said traverse, the thread passing from said second arm to said third arm moving in a substantially vertical direction and xiiakingslightly more than tangential contact with said second arm throughout the winding of said cone, said thread guide being pivoted and being moveable with respect'to'said third arm so that the arc of contact of the thread .on` said thread guide and the arc of Contact of the thread on said third arm decreases as the conc isbuilt up and as the speed of the thread increases, the force acting on said third arm due to the tension of the thread tending to rotate said third arm' clockwise with respect to the pivot of said hub and the force acting on said third arm due to the, friction of the thread tending to rotate said third arm counter-clockwise with respect tothe pivot of said hub whereby said third arm functions to Ymove said second arm slightly to reduce the bearing offsaid second arm on said thread as the Aspeed of said thread increases with the build up` of said cone so that shaky and jumpy operation of said leverage is substantially eliminated particularly as said cone builds up and said leverage operates in a positive manner to stop the thread winding machine upon substantial reduction in thread tension.

5 References Cited in the file of this patent `UNITED STATES PATENTS 801,941 Wardwell Oct. 17, A1,595,705 Cannon ..2 Aug. 10, l0 1,673,246 .Tones June 12, 1,841,680 Schaum Jan. 19, 1,856,513 Schweiter May3, 2,361,426 Spangler et al. t Oct. 31,

FOREIGN PATENTS 15 553,309 France May 23, 583,482 France Oct.` 31, 664,780 France Apr. 29,