US3347475A

US3347475A - Yarn traversing mechanism

Info

Publication number: US3347475A
Application number: US603331A
Authority: US
Inventors: Ernest M Sternberg
Original assignee: Monsanto Co
Current assignee: Monsanto Co
Priority date: 1965-02-26
Filing date: 1966-12-20
Publication date: 1967-10-17
Anticipated expiration: 1984-10-17

Description

Oct. 17, 1967 E. M. STERNBERG YARN TRAVERSING MECHANISM Original Filed Feb. 26. 1965 'l 0-- 1 16.2. a: t r 20 INVENTOR ERNEST M.STERNB RG W t J 1.

' ATTORNEY' United States Patent Claims. (Cl. 242-26.1)

The present application constitutes a divisional of application Ser. No. 435,636, filed Feb. 26, 1965.

This invention relates to package winding mechanisms for winding strands, yarns, threads, slivers, or the like, of filamentous materials on cones, tubes, bobbins, or other similar revoluble package supporting members at high speeds. More particularly, the invention relates to a novel traversing mechanism for use in winding continuous filamentous material on a spool, bobbin or like holder in a uniform, controllable manner.

Throughout the instant specification and claims, the term strand is intended to include thread, yarn, sliver, fiber, filament, wire, ribbon, fibrous or filamentary bundles, and the like.

In the textile industry, strands obtained by various processes are wound into packages on bobbins or like revoluble supporting members. In such winding operations, it is necessary to employ some means of axially traversing the strand back and forth along the package. Various and sundry traversing means have heretofore been proposed for use in such winding operations. These prior devices have ordinarily comprised a reciprocating member or guide which travels back and forth adjacent the surface of the rotating package support member on which the strand material is being wound. In general, the reciprocating motion of the guide member has been accomplished by means of a cam, or the like. As is widely recognized, such prior cam arrangements suffer from undue wear, are limited and cumbersome in the manner of their manipulation, and lack the degree of compactness desired in many limited scale operations, particularly those encountered in testing and experimentation.

With these desires and prior art shortcomings in mind, it therefore becomes a general object of my invention to provide an improved traversing mechanism for use in strand winding and packaging operations, which mechanism possesses a compactness of arrangement, flexibility in manipulation and precision of result heretofore unattained.

A further object is such a traversing mechanism which may be economically manufactured in the form of one or more packaging stations.

According to the present invention, the foregoing and other objects are attained by providing an improved traverse mechanism of newfound compactness in'arrangement and flexibility of operation, a mechanism which effects a uniquely advantageous use of the basic principle of converting two independent inputs into a combined differential output to thereby control the program of movement of a traverse guide along a strand package to obtain wide variation in package configuration with a high order of control. Basically, such a mechanism takes the form of a pair of input elements driven through reciprocal paths of pre-selected lengths at a pre-determined difference in velocities, which input elements are linked to drive a reciprocably mounted output element and an associated traversing guide in a direction and at a velocity according to the algebraic sum of the individual velocities of the input elements. A further important aspect of this invention essential to optimumpackage configurations resides in the provision for a high ratio of input speeds productive of greater uniformity in traverse guide speed and in the provision that such input speeds are relatively prime to one another, a feature which minimizes the number ofcoincident reversal points experienced in the travel of the traverse guide. As employed in the instant specification and appended claims, the term relatively prime input speeds connotes that relationship wherein one of the input speeds is not divisible by the other. (An example of such relationship'being the numbers, or speeds, 12 and 25. That is, the input speeds are so related as to have no common divisor save unity.)

With regard to the feature of maintaining a high ratio of input speeds, it has been found impractical to operate the present device at ratios of less than 3:1 where optimum package configurations are to be obtained. At input speed ratios less than 3:1, it has been found that the resulting package often exhibits objectionable ridge formations because of an undue lack of uniformity of traverse guide speed. This result becomes readily apparent when one considers the program described by a traverse guide driven according to the present invention at an input speed ratio of, for example, 2:1. The traverse guide will experience a Variation in velocity between a maximum factor of 2 and a minimum of 0.5, a normally intollerable variation; however, at a ratio of input speeds of, for example, 11:1, traverse guide velocity will only vary between the limits of a factor of 6 and 5; similarly, at still higher input ratios, the percentage variation in guide velocity becomes proportionately smaller. It is therefore preferred to operate the herewith disclosed traverse mechanism at as high a ratio of input speeds as is practicable.

Where it is desired to produce package configurations exhibiting flattened mid-portions, a further important aspect of this invention resides in the provision of a differential in stroke lengths of the input elements, an arrangement which causes the traverse guide to travel uniformly over the mid-portion of the package being constructed. Additionally, where it is desired to construct a package exhibiting a difference in tapers adjacent each end, such as is expressed by the efficient tear drop configuration, the helix angle formed in at least one of the fishing-reeltype winding screws is caused to decrease to a minimum adjacent one lengthwise extremity of the stroke of the input element, an arrangement which causes the traverse guide to accelerate its travel over that portion of the package being constructed.

To facilitate a better understanding of the details of construction of a possible embodiment of my invention, reference shall now be had to the drawings as being illustrative, but not limitative, thereof, wherein like reference numerals refer to similar parts and in which:

FIG. 1 is a simplified schematic of the invention as characterized by a pair of reciprocably mounted, freefioating rack elements driving a combined differential output gear, and

FIG. 2 is a simplified depiction showing one possible alternative drive arrangement using fishing-reel-type reverse helical screws in lieu of the pinion arrangement of FIG. 1.

Referring now to the schematic representation of FIG. 2, the traversing mechanism, generally indicated by numeral 10, is seen to comprise a pair of parallel extending, fishing-reel-type reverse helical

traverse winding screws

12, ,14, which screws are each characterized by endless, reverse

helical cam grooves

16, 18, respectively, formed in the surfaces thereof such that a follower inserted there- .in will trace the groove from one end of the screw to the other in a continuous fashion as the screw is caused .to rotate. Each of the

screws

12, 14 has coaxially mounted .thereon and in sliding engagement therewith a sleeve-

like input element

20, 22, respectively, each having a follower shoe protruding from its inner surface and sized to snugly engage the

endless grooves

16, 18. It will be apparent that upon causing the screws to rotate about fixed axes, the

input elements

20, 22 Will be caused to travel along the length of the screws at a rate dependent upon both the speed of screw rotation and the helix angle at a given point along the groove (which angle is that described by a tangent to a given point along the groove with a line parallel to the axes of rotation of the screws).

An advantageous arrangement for driving the screws at the desired speed ratio is found in the provision of a variable speed motor 24 driving a timing belt, chain or the like 27 through power take-off sprocket 26, the belt being entrained about

screw sprockets

28, 30 to drive

screws

12, 14, respectively.

A most beneficial feature of the present invention resides in the provision of a reciprocating mechanism (which, in the arrangement illustrated in FIG. 2, comprises motor 24, power sprocket 26, timing belt 27,

screw sprockets

28, 30 and winding screws 12, 14) which is so designed as to drive the

input elements

20, 22 at a high velocity ratio which are relatively prime to one another, i.e. indivisible by one another. For example, this may be accomplished by providing a 19-tooth sprocket as element 28 and a 61-tooth sprocket as element 30, an arrangement resulting in a speed ratio, for a given identity of helix angle, between the input elements of greater than the 3:1 ratio considered requisite to satisfactory package formation, as well as being a speed ratio possessing the relationship of being relatively prime to one another. It is, of course, contemplated that a suitable gear train may be incorporated between the motor 24 and the

sprockets

28, 30 to produce still higher ratios of input velocities and a concomitant greater uniformity in output velocity through the combined differential output gear 62.

The motion of the combined differential output element (the gear 62 in FIG. 2) is transmitted by suitable means, such as a rod 38, to a conventional ringtraveler arrangement normally comprising a ring member 40 and a strand traveler 42 mounted to freely slide about the ring with a minimum of friction. Bobbin 44 is driven at high rotative speeds by any suitable means, not shown, to cause the supply strand 46 to travel through balloon guide 48, thence through traveler 42 to then be enwrapped about the strand package 50 being formed. By operation of the traversing mechanism, the ring-traveler assembly is caused to traverse bobbin 44 axially at a speed equal or proportional to and in a direction according to the algebraic sum of the velocities of the

respective input elements

20, 22. It will be appreciated that, by operation of the instant traversing mechanism, there is produced a package characterized by a differential-fill winding wherein the traverse of the yarn traveler guide axially of the package is of uniform, successively displaced strokes lengthwise of the package during the winding operation.

A further important feature of my invention, as previously mentioned, lies in an arrangement productive of packages exhibiting uniformly flattened mid-portions. This is readily accomplished by sizing the longitudinal dimensions of

groove

16, 18 to have a pre-chosen difference in effective stroke lengths, this differential being indicated by the distance labeled D in FIG. 2. By this arrangement it will be appreciated that the builder motion described by the ring-traveler will experience a uniform residence time over the mid-portion of the package equal to onehalf the difference in effective stroke lengths of the

input elements

20, 22. By varying this difference in stroke lengths, a package having any desired length of flattened mid-portion may be formed.

As an alternative to the reverse

helical winding screws

12, 14 of FIG. 2, the

racks

58, 60 which interconnect

input elements

20, 22 with differential output gear 62 may be driven by

pinion gears

64, 66, respectively, as shown in FIG. 1. Depending on the particular arrangement de- 4 sired, the

racks

58, 60 may be modified by the addition of outwardly facing toothed-portions to accommodate the pinion arrangement shown in FIG. 1; of course, the pinion gears may be mounted between the rack members, thereby avoiding the need of forming a double-toothed rack.

It may now be appreciated that there has been herewith disclosed a novel and beneficial traversing mechanism of compact construction which is highly precise and flexible in operation and which embodies the principles and attendant advantages of a combined differential output motion being transmitted to the traveler guide. Obviously, numerous modifications and variations of the present invention, both as to its construction and mode of operation, are possible in light of the above teachings. It is, therefore, to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.

What is claimed is:

1. In a winding mechanism for use in strand winding operations, a traversing mechanism comprising a pair of reciprocably mounted input elements, means to reciprocate said elements through paths of pro-selected lengths at pro-determined difference in velocities, a reciprocably mounted output gear, a reciprocably mounted strand traversing guide responsive to movement of said output element, linkage means interconnecting said output element with each of said input elements and operative to move said output gear according to the individual movements of said pair of input elements, said linkage means comprising a pair of reciprocably mounted rack members, each engaging said output gear, and being driven by one of said input elements, whereby said traversing guide is caused to move in a direction and at a velocity according to the algebraic sum of the velocities of said input elements.

2. The mechanism as recited in claim 1 wherein said reciprocating means comprises a pair of rotatably mounted fishing-reel-type winding screws, each characterized by an endless, reverse helical groove formed along its surface, each of said input elements engaging one of said grooves to be urged therealong upon rotation of the screw to thereby describe said reciprocating paths.

3. The mechanism as recited in claim 2 wherein the helix angle described by at least one of said grooves decreases to a minimum adjacent one lengthwise extremity thereof, whereby said traversing guide reaches a maximum velocity substantially at one extremity of its reciprocation.

4. The mechanism as defined in claim 2 wherein said reciprocating means is further characterized by a drive means operative to drive said screws at rotative speeds relatively prime to one another to thereby minimize the number of coincident reversal points in the travel of said traversing guide.

5. In a winding mechanism for use in strand winding operations, an improved traversing mechanism comprising a pair of pinion gears mounted in side-by-side relationship, and output gear, a pair of reciprocably mounted rack members, each engaging said output gear and being driven by one of said pinion gears through paths of preselected lengths at a pre-determined difference in velocities, a reciprocably mounted strand traversing guide responsive to movement of said output gear, whereby said guide is caused to move in a direction and at a velocity according to the algebraic sum of the velocities of said rack members.

6. The mechanism as defined in claim 1 wherein the reciprocal paths of said input elements are of differential lengths, whereby said traversing guide experiences a maximum residence period during the mid-portion of its travel to thereby generate a package exhibiting a substantially flat mid-portion equal to one-half the difference in path lengths of said input elements.

7 The mechanism as defined in claim 3 wherein said reciprocating means is further characterized by a drive means operative to drive said screws at rotative speeds relatively prime to one another to thereby minimize the number of coincident reversal points in the travel of said traversing guide.

8. The mechanism as defined in claim 2 wherein the reciprocal paths of said input elements are of differential iengths whereby said traversing guide experiences a maximum residence period during the mid-portion of its travel to thereby generate a package exhibiting a substantially flat mid-portion equal to one-half the difference in path lengths of said input elements.

9. The mechanism as defined in claim 4 wherein the reciprocal paths of said input elements are of differential lengths whereby said traversing guide experiences a maxi mum residence period during the mid-portion of its travel to thereby generate a package exhibiting a substantially fiat mid-portion equal to one-half the difference in path lengths of said input elements.

10. The mechanism as defined in claim 7 wherein the reciprocal paths of said input elements are of differential lengths whereby said traversing guide experiences a maximum residence period during the mid-portion of its travel to thereby generate a package exhibiting a substantially fiat mid-portion equal to one-half the difference in path lengths of said input elements.

References Cited UNITED STATES PATENTS 2,577,131 12/1951 Keight 242*26.4 2,629,559 2/1953 Ayala 24226.4 3,243,131 3/1966 Greive 24226.3 FOREIGN PATENTS 45,927 5/ 1962 Poland.

STANLEY N. GILREATH, Primary Examiner.

Claims

5. IN A WINDING MECHANISM FOR USE IN STRAND WINDING OPERATIONS, AN IMPROVED TRAVERSING MECHANISM COMPRISING A PAIR OF PINION GEARS MOUNTED IN SIDE-BY-SIDE RELATIONSHIP, AND OUTPUT GEAR, A PAIR OF RECIPROCABLY MOUNTED RACK MEMBERS, EACH ENGAGING SAID OUTPUT GEAR AND BEING DRIVEN BY ONE OF SAID PINION GEARS THROUGH PATHS OF PRESELECTED LENGTHS AT A PRE-DETERMINED DIFFERENCE IN VELOCITIES, A RECIPROCABLY MOUNTED STRAND TRAVERSING GUIDE RE-