US3764090A

US3764090A - Thread laying mechanism for precision winding of pineapple bobbins

Info

Publication number: US3764090A
Application number: US00262993A
Authority: US
Inventors: R Gerber
Original assignee: Machinenfabrik Schweiter AG
Current assignee: Machinenfabrik Schweiter AG
Priority date: 1971-06-30
Filing date: 1972-06-15
Publication date: 1973-10-09
Anticipated expiration: 1990-10-09
Also published as: DE2136011C3; GB1378928A; JPS513818B1; CH523841A; AT332261B; DE2136011A1; IT960471B; ATA450072A; DE2136011B2; FR2144335A5

Abstract

A slider on a movable adjusting guide bar to reduce the traverse distance of the yarn guide as the diameter of the bobbin increases, cooperates with a slider in a fixed track driven by a grooved roll. To prevent undesired jarring upon reversal of traverse direction, a damping device, e.g., a cylinder and piston damping arrangement is provided, one end thereof being fixed and the other end linked to a point of the adjusting guide bar.

Description

United States Patent [191 Gerber [451 Oct. 9, 1973 THREAD LAYING MECHANISM FOR PRECISION WINDING OF PINEAPPLE BOBBINS [75] Inventor: Robert Gerber, Horgen, Switzerland [73] Assignee: Maschinenfabrik Schweiter AG, I

Horgen, Switzerland [22] Filed: June 15, 1972 [2]] App]. No.: 262,993

[30] Foreign Application Priority Data June 30, 1971 Switzerland 9639/71 [52] [1.8. CI. 242/43.l [51] Int. Cl B65h 54/32 [58] Field of Search 242/43, 43.1

[56] References Cited UNITED STATES PATENTS 2,206,582 7/1940 Shipman 242/43.l

8/1942 Treckman 242/43.1 10/1967 Marciniak 242/43.l X

Primary Examiner-Stanley N. Gilreath Attorney-Flynn & Frishauf ABSTRACT A slider on a movable adjusting guide bar to reduce the traverse distance of the yarn guide as the diameter of the bobbin increases, cooperates with a slider in a fixed track driven by a grooved roll. To prevent undesired jarring upon reversal of traverse direction, a damping device, e.g., a cylinder and piston damping arrangement is provided, one end thereof being fixed and the other end linked to a point of the adjusting guide bar.

3 Claims, 1 Drawing Figure This invention relates to a thread laying mechanism for the precision winding of so'-called pineapple bobbins. It relates more particularly to precision cross winding machines in which the traverse mechanism uses a slider reciprocally moved in its track by a grooved traverse roll and carrying the pivot of a bell crank, one arm of which carries a yarn guide and the other of which is constrained by the movement of a second slider carried on its extremity, which moves back and forth in an adjusting guide bar, the angular position of which is controlled by a winding bracket in response to the diameter of the bobbin being wound in such a way that the thread lay reversal points are shifted closer together as the bobbin diameter increases.

In the winding of pineapple bobbins, which are bobbins, the end surfaces of which are tapered outwardly, by means of thread laying mechanisms of the type just described and heretofore known, the difficulty arises that the inertia of the yarn guide and its bell crank resulting from the mass of these components exerts a mechanical shock on the adjusting guide bar in the direction of swing of the latter on each reversal of direction of the slider driven by the grooved traverse roll. Quite apart from the increased wear of the components involved thus arising, this behavior of the machine generally impairs the quality of the bobbin by producing irregularities in the end surfaces of the winding.

lt is an object of this invention to prevent the adjusting guide bar from receiving a kick on each reversal of the direction of the yarn guide and thereby will make possible the winding of pineapple bobbins with tapered surfaces of high regularity and greater precision.

SUBJECT MATTER OF THE PRESENT INVENTION Briefly, between a point of the adjusting guide bar longitudinally offset from its fulcrum and a reference point which, like the said fulcrum, has a fixed relation to the machine frame, a clamping device is provided in such a way that it is effective in the direction of swing of the adjusting guide bar. Since the adjusting guide bar is adjustable over a predetermined limited angular range, the damping element is preferably composed of a piston and cylinder arrangement in which the region of the damping movement is automatically shifted in accordance with the particular angular setting of the adjusting guide bar. To provide compact construction, the damping device is preferably connected to the ad justing guide bar by means of a second bell crank pivoted on a fixed point of the machine, in such a manner that one crank arm may be moved by the end of the adjusting guide bar connected to the winding bracket and the other crank arm has a swivel connection with the damping device.

In order that optimum effective damping may be obtained with minimum variation of the setting of the adjusting guide bar, the aforesaid second bell crank is arranged so that over the adjustment range of the adjusting guide bar, the arm of the bell crank connected to the adjusting guide bar, is directed approximately parallel to the adjusting guide bar, while the other arm of the bell crank is directed approximately perpendicular to the direction of operation of the clamping device.

An illustrative embodiment of the invention will be more particularly described with reference to the accompanying Drawing, which is a perspective schematic view of a thread laying mechanism. 1

As shown in the drawing, the thread laying mechanism for winding pineapple bobbins on a precision cross winding machine comprises a motor-driven traverse roll 1 with guide grooves 2. Guide rails 3a (shown wwth right end cut away) and 3b parallel to the axis of roll 1 can serve to fix the path in which the slider 4 is caused to move back and forth over substantially the entire length of the roll 1. The movement of the slider 4 is produced by a follower 5 in the form of a stud extending downwardly from the underside of slider 4 into the grooves 2 of the roll 1.

A bell crank 7 is pivotally mounted on a bearing 6 carried by slider 4. One arm of bell crank 7 carries'the yarn guide 8 which moves back and forth in synchronism with the'slider 4 and lays a thread (not shown) on a rotating bobbin (likewise not shown). ln order .that the reversing points of the thread traverse on the bobbin may be shifted towards the middle of the bobbin in response to increasing diameter of the bobbin, which is a requirement for so-called pineapple bobbins, the other arm of bell crank 7 carries a second slider 10 with a swivel mounting on a bearing 9. This second slider 10 is movable back and forth in the guide channel of an adjusting guide bar 11. I

in the illustrated embodiment of the invention, the adjusting guide bar 11 has a swivel mounting in its mid portion on a bearing 12 fixed with respect to the machine frame which allows it to be swung in a plane parallel to the directions of movement of sliders 4 and 10. As shown in the drawing, the bearing 12 is provided by a stud on theprojecting end of a bracket 13mounted on guide rail 3a.

The left end, as shown in the drawing, of adjusting guide bar 11 is forked so as to be able to engagea stud (not shown) mechanically linked (by means not shown) to the winding (likewise not shown). The winding bracket rides on the surface of the bobbin being wound and, moving with the latters increase in diameter, controls the angular position of adjusting guide bar 11 relativeto the guide rails 3a and 3b so that with increasing diameter of the bobbin the adjusting guide bar 11 is swung more and more out of parallelism with guide rails 3a and'3b, for example counter-clockwise. As a result, the two reversal points of yarn guide 8 are shifted inward, as desired. a

In order to provide camping of the kick transmitted to adjusting guide bar 11 upon reversal of the movement of slider 4 as driven by traverse roll 1, a damping device is provided which suitably comprises a cylinder 15, shown partly cut away, and a piston 17 movable therein by means of a piston rod 16. The path of the damping movement of piston 17 automatically adjusts itself to changes in the position of the mechanism. The

free end of piston rod 16 has a swivel mounting on a pivot 18 which has a fixed position with respect to the machine frame. As illustrated, the pivot 18 is located on bracket 13. Cylinder l5, furthermore, also has a swivel mounting, in this case provided on one arm of a second bell crank 19, of which the other arm engages one end of the adjusting guide bar 11 by means of a stud 20 in the fork 14. The pivot 21 of this second bell crank 19 is located on a second bracket 22, shown in the drawing to the left of first bracket 13 on guide rail 3a, the position of which is fixed with respect to the machine frame.

By virtue of this arrangement, the

damping device

15, 16, 17 can freely change its position to correspond with the angular adjustment of adjusting guide bar 11 so as to optimize the position of its damping effect to the adjusting guide bar 1 1. For this purpose, bell crank 19 is so fashioned and its pivot 21 is so disposed that over the range of angular adjustment of adjusting guide bar 11 the arm of bell crank 19 which engages fork 14 is as nearly as possible parallel to adjusting guide bar 1 1 and the crankarm connected to cylinder 15 is as nearly as possible directed at right angles to piston rod 16. This permits the position of an elongated damping device more or less parallel to adjusting guide bar 1 1, thus providing a conveniently compact form of construction.

It will readily be seen, however, that bell crank 19, or damping cylinder 15 directly, could be connected to other positions on adjusting guide bar 11 and, likewise, the fixed pivots l8 and 21 of the clamping device could be located at other positions. Instead of the pistons and cylinder damping device shown, moreover, other damping means, for example spring means, could be used.

1 claim:

1. A thread laying mechanismfor precision winding of pineapple bobbins comprising: 7

a grooved traverse roll and driving means therefor;

a first slider mounted in a fixed rectilinear guide and having a follower stud engaging said traverse roll to provide reciprocating movement to said slider;

a bell crank pivotally mounted on said first slider carrying on one of its arms a yarnguide and on its other arm a second slider, said second slider being held reciprocally movable in a channel of an ad' justing guide bar which is pivotally mounted on a fixed bearing and is arranged to have its position controlled at least at one end, through mechanical linkage to a winding bracket, in accordance with the diameter of the bobbin being wound, whereby the traverse length may be progressively reduced with increase of said diameter; and

a damping device connecting a point of said adjusting guide bar offset from its said bearing to a fixed point of the machanism, said damping device being arranged so as to operate in the direction of swing of said adjusting guide bar, the damping device being pivotally connected with said adjusting guide bar by means of a second bell crank which is mounted on a fixed bearing, whereby one arm of said second bell crank is movable by the end of said adjusting guide bar which is connected to said winding bracket and the other arm of said second bell crank is pivotally connected with said clamping device.

2. A thread laying mechanism as defined in claim 1, in which said clamping device comprises a cylinder and a piston mounted therein and which is so arranged that the path of the damping movement is automatically adjusted.

3. A thread laying mechanism as defined in claim 1, in which said second bell crank is so arranged that in the angular adjustment range of said adjusting guide bar the arm of said second bell crank connected to said adjusting guide bar extends roughly parallel to said adjusting guide bar and the otherarm of said second bell crank extends roughly perpendicularly to the operating direction of said damping device.

Claims

1. A thread laying mechanism for precision winding of pineapple bobbins comprising: a grooved traverse roll and driving means therefor; a first slider mounted in a fixed rectilinear guide and having a follower stud engaging said traverse roll to provide reciprocating movement to said slider; a bell crank pivotally mounted on said first slider carrying on one of its arms a yarn guide and on its other arm a second slider, said second slider being held reciprocally movable in a channel of an adjusting guide bar which is pivotally mounted on a fixed bearing and is arranged to have its position controlled at least at one end, through mechanical linkage to a winding bracket, in accordance with the diameter of the bobbin being wound, whereby the traverse length may be progressively reduced with increase of said diameter; and a damping device connecting a point of said adjusting guide bar offset from its said bearing to a fixed point of the mechanism, said damping device being arranged so as to operate in the direction of swing of said adjusting guide bar, the damping device being pivotally connected with said adjusting guide bar by means of a second bell crank which is mounted on a fixed bearing, whereby one arm of said second bell crank is movable by the end of said adjusting guide bar which is connected to said winding bracket and the other arm of said second bell crank is pivotally connected with said damping device.

2. A thread laying mechanism as defined in claim 1, in which said damping device comprises a cylinder and a piston mounted therein and which is so arranged that the path of the damping movement is automatically adjusted.

3. A thread laying mechanism as defined in claim 1, in which said second bell crank is so arranged that in the angular adjustment range of said adjusting guide bar the arm of said second bell crank connected to said adjusting guide bar extends roughly parallel to said adjusting guide bar and the other arm of said second bell crank extends roughly perpendicularly to the operating direction of said damping device.