Traverse Cam And Follower For Winders

Abstract

A traverse cam and follower is provided for winding machines that is capable of operating at high winding speeds to much better advantage than has heretofore been possible. The traverse cam is characterized by a reversing spiral of three grooves, and the follower by a shoe for riding in the central groove to serve as a crossing guide and by stud elements spaced at each side of the shoe for riding in the outer grooves to bear the cam thrust. This arrangement allows excellent control of the follower during reversal at the end of each stroke, results in remarkably smooth and quiet operation, and adapts well to use in traverse cams of considerably smaller diameter than is usual, which lighten the traverse mechanism substantially and lower cam surface speed so as to lessen follower wear materially.

Description

BACKGROUND OF THE INVENTION

In winding machines of the sort employed to build packages of textile strand material by placing successive, alternately reversed, spiral-wound layers of the strand material on a supporting core or bobbin, the winding pattern is commonly directed by a strand guide that is arranged for reciprocation through follower engagement with a cylindrical traverse cam having intersecting, oppositely directed, spiral grooves formed therein with connecting portions that effect reversal of the strand guide at the ends of the traverse stroke.

The follower engagement with the traverse cam is ordinarily provided for by fitting the strand guide with an elongated shoe (or boat) adapted for riding in the cam grooves to produce strand guide reciprocation from cam rotation. But as the follower shoe must be sufficiently elongated to lead smoothly across the cam groove intersections, it follows that the portions connecting the spiral grooves for reversal must be specially formed to allow passage of the shoe therethrough during reversal, and this factor renders satisfactory control of the shoe at reversal a practical impossibility, particularly as it is desirable to effect the reversal as rapidly as possible.

The art has sought for some time to deal with this difficulty because it substantially restricts practical operating speeds. Examples of solutions heretofore proposed are found in U.S. Pat. Nos. 3,048,054 and 3,407,262. The present invention eliminates the difficulty to exceptionally better advantage than has previously been possible.

SUMMARY OF THE INVENTION

According to the present invention a traverse mechanism for textile winding machines is provided in which the traverse cam is representatively formed with a reversing spiral of three grooves, and the strand guide follower with an elongated shoe for riding in the central groove to serve as a crossing guide and with stud elements spaced at each side of the shoe for riding in the outer grooves to bear the cam thrust. The result of this arrangement is to stabilize the follower means nicely during reversal at the ends of the traverse stroke and thereby maintain the traverse mechanism operating smoothly at exceptionally high speeds.

For this purpose, at least three grooves are needed in the cam spiral in order to accommodate at least two spaced stud elements to provide the necessary follower means stability. Also, the elongated shoe should be arranged to ride in the central groove of the spiral in order to allow a symmetrical follower means structure to be used that will act comparably during reversal at the respective ends of the spiral. More than three grooves may be used, if desired, but when this is done the further grooves should be added in increments of two for the same considerations of symmetry.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic illustration of a textile winding machine arrangement in which a traverse mechanism embodying the present invention might be employed;

FIG. 2 is a side elevation of the traverse mechanism diagrammed in FIG. 1;

FIG. 3 is an enlarged sectional detail taken substantially at the line 3--3 in FIG. 2;

FIG. 4 is a full side elevation of the traverse cam employed in the FIG. 2 mechanism with a three-groove spiral diagrammed thereon;

FIG. 5 is an enlarged fragmentary side elevation of the FIG. 4 traverse cam showing the cam groove arrangement with the follower means represented in relation thereto;

FIG. 6 is a side elevation of the follower means; and

FIGS. 7 and 8 are respective plan and right-end views corresponding to FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The textile winding machine diagrammed in FIG. 1 of the drawings is of the surface driven type employing a traverse mechanism according to the present invention in dual traverse form at 10 for directing two delivered strands S and S' to respective print rolls 12 and 12' by which the winding pattern is transferred to bobbin cores C and C' carried on chuck rolls 14 and 14' that are rotatably mounted on biased swing arms 16 and 16'. The print rolls 12 and 12' are driven and, as the biased swing arms 16 and 16' maintain the bobbin cores C and C' initially, and thereafter the strands S and S' wound thereon, in surface contact with print rolls 12 and 12', the result is to build the strands S and S' into packages P and P' of alternately reversed, spiral-wound layers following the winding pattern determined by the traverse mechanism 10 and transferred by the print rolls 12 and 12'.

FIG. 2 shows the structure of a traverse mechanism 10 embodying the present invention suitably for use in a winder arrangement of the foregoing sort as comprising a mounting plate 18 to which a tubular housing 20 is secured for carrying a traverse cam 22 in bearing units 24 and 26. The extending end of housing 20 is capped at 28 beyond the outboard bearing unit 24, while the other end extends through mounting plate 18 to contain the inboard bearing unit 26 thereat and allow projection of a traverse cam stub shaft portion 29 for driving connection. The secured arrangement of the cam housing 20 mounting plate 18 includes cantilever braces 30 and 31 fixed above and below housing 20 (compare FIGS. 2 and 3).

As seen best in FIG. 3, opposite sides of the cam housing 20 are flatted and fitted with inset guide blades 32 and 32' to engage strand guide follower means 34 and 34' at elongated slots 36 and 36' formed through the flatted sides of housing 20 to provide for riding association of the follower means 34 and 34' with traverse cam 22. The slots 36 and 36' have a length sufficient to accommodate the traverse stroke and the guide blades 32 and 32' thereat closely define a linear path for reciprocation of the follower means 34 and 34' in response to rotation of the traverse cam 22.

FIG. 4 shows a separate side elevation of the traverse cam 22 with a three-groove reversing spiral 38 such as is used according to the present invention diagrammed thereon, while FIG. 5 details a lengthwise constant velocity portion of cam 22 with a related representation of a follower means 34. Although traverse cams employed in winder arrangements of the FIG. 1 type are commonly of 21/2 inches diameter, a traverse cam 22 embodying the present invention has been used successfully at a diameter of 11/2 inches so as to reduce substantially the cam surface speed as well as the spiral length of the reversing spiral 38 and thereby lessen materially the wear influences on the follower means. The 11/2 inches cam 22 just referred to was formed for a traverse stroke of 12 inches with the three grooves 40, 42 and 44 of the reversing spiral 38 making 41/2 revolutions in each direction. For an intermediate 1570.degree. of revolution in each direction the grooves 40, 42 and 44 were formed with constant velocity portions at a lead angle of 29.degree. 53', leaving 25.degree. for angular acceleration and deceleration in effecting follower means reversal at the respective ends of the traverse stroke.

The grooves 40, 42 and 44 were each proportioned at a width of one-eighth inch and depth of three thirty-seconds inch, and were separated by lands of one-eighth inch width. The follower means 34 (or 34') provided to ride in these grooves, as shown further in FIGS. 6, 7 and 8, was formed with a body portion 46 having a width suited for slidable disposition in the cam housing slot 36 (or 36') and a groove 48 at one side face for slidable engagement with the adjacent guide blade 32 (or 32'). A thread guide notch 50 was arranged in a lip portion 52 projecting from the outer face thereof (i.e., the top face in FIGS. 6, 7 and 8), and three recesses were aligned at the opposite face in correspondence with the spacing of spiral grooves 40, 42, and 44 to carry an elongated shoe 54 in the middle recess for riding in the central groove 42 and cylindrical stud elements 56 and 58 in the other recesses for riding in the outer grooves 40 and 44. The elongated shoe 54 included a centrally positioned shank portion 60 at which it was pivotally carried in the middle recess of the follower means body portion 46, while the stud elements 56 an 58 were press fitted in the other recesses, the whole of follower means 34 (or 34') being formed of nylon 6 material. As thus arranged, (see FIGS. 6, 7 and 8), the cylindrical axes of the stud elements 56 and 58 and the pivot axis of shoe 54 were disposed parallel to each other and in the same plane of the follower means.

In operation, the elongated shoe 54 served as a crossing guide at the intersections of the reversing spiral 38, and was suitably proportioned in length for this purpose as indicated by the dotted line representation that is included in FIG. 5 (90.degree. out of phase). Because of this lengthwise extent of the shoe 54 it was, of course, necessary to widen the central spiral groove 42 sufficiently at its 25.degree. portions of angular acceleration and deceleration to clear the shoe adequately during reversal, but this was easily done because control of the follower means 34 (or 34') was provided for by the stud elements 56 and 58 so that a precise widthwise fitting of the shoe 54 in groove 42 was not needed at any point in its travel. On the other hand, the cylindrical stud elements 56 and 58 were proportioned to fit the outer spiral grooves 40 and 44 closely and carried at an alignment with both the pivot axis of shoe 54 and the linear path of the traverse stroke, so that the follower means 34 (or 34') was stabilized quite effectively against cocking or other erratic action during the traverse end reversals. It is also notable, as will be seen from a consideration of the dotted line representation of follower means 34 in FIG. 5, that even at the spiral groove intersections one of the stud elements 56 or 58 maintains control of the follower means except at the gap immediately following the intersection midpoint, so that the crossing guide function of the shoe 54 is minimal and the cam thrust is borne entirely by the stud elements 56 and 58 for all practical purposes.

As a result, a traverse mechanism arranged in the foregoing manner can be operated smoothly and effectively at surprisingly high speeds, a test speed of 6,500 r.p.m. having been attained without pushing the mechanism to its limit. Such a speed means that continuous spun filament, for example, may be received at a delivery speed in the order of 4,000 meters per minute and wound into packages at a helix angle of about 6.degree. with ease, which is substantially beyond previous operating possibilities.

Comparable winding performance can be obtained by providing a plurality of reversing spirals on the traverse cam at spaced locations with follower means at each spiral for winding a group of smaller packages, and by operating in either single or dual traverse fashion. When a dual traverse is used, or when more than one spiral is employed, it is desirable to phase the follower means for balanced simultaneous reversal at opposite ends of the traverse stroke.

The present invention has been described in detail above for purposes of illustration only and is not intended to be limited by this description or otherwise to exclude any variation or equivalent arrangement that would be apparent from, or reasonably suggested by, the foregoing disclosure to the skill of the art.

Claims

I claim:

1. In a winder for textile strand material and the like, in which a grooved traverse cam and follower means are employed for directing the winding pattern, the improvement which comprises at least one reversing spiral of at least three grooves formed in said traverse cam, and a follower means carrying an elongated shoe for riding in one groove of said spiral to serve as a crossing guide, together with spaced stud elements for riding in the other grooves of said spiral to bear the cam thrust.

2. In a winder for textile strand material and the like, the improvement defined in claim 1 and further characterized in that the number of grooves in said spiral equals 1 plus n, where n is an even number, and in that said shoe is carried to ride in the central groove.

3. In a winder for textile strand material and the like, the improvement defined in claim 2 and further characterized in that said follower means is guided in a linear path for reciprocation in response to rotation of said traverse cam, in that said shoe is pivotally carried for riding in said spiral groove, and in that said stud elements are cylindrical and are spaced at each side of said shoe with the cylindrical axes of said stud elements and the pivot axis of said shoe disposed parallel to each other and in a plane of said follower means aligned with said linear path.

4. In a winder for textile strand material and the like, the improvement defined in claim 3 and further characterized in that two of said follower means are disposed for riding said traverse cam spiral at diametrically opposite positions, and said follower means are phased to reverse simultaneously at opposite ends of said spiral.