EP1554209B1 - Device for winding a yarn on a holder driven in rotation - Google Patents

Abstract

Yarn is dispensed by a yarn guide mobile in translation parallel to generatrices of a rotary holder. The device comprises a carriage receiving the yarn guide and having fittings for being coupled with a flexible transmission and driving member adapted to impart to the yarn guide a reciprocating movement, in combination with a translational guide, parallel to the generatrices of the rotary holder. The yarn guide, the translational guide and the fittings being offset at an angle on the carriage to generate an additional speed component proximate to changeover points.

Description

The invention relates to the technical sector of the winding of a textile yarn on a support, generally in the form of a cylindrical mandrel capable of being rotated. The cylindrical mandrel or support may be rotated either by its axis or by one of its generators. This winding can be used for spinning, drawing, texturing, twisting, assembling and winding operations.

Recall, in a manner perfectly known to a skilled person, the wire is distributed along a generatrix along the coil; in the form of inclined and parallel turns. Generally, the speed of movement of the wire guide is constant. On the other hand, it is necessary to reverse the movement at the ends of the spool as quickly as possible to prevent the edges of the spool from being thicker than its center.

Many technical solutions have been proposed to achieve so-called systems of back and forth, at a very high speed, taking into account that the windings must have a perfect density throughout their thickness. Such windings can be straight-sided (cylinder coil) or inclined lateral flanks (conical coil), or even conical generatrix.

According to the patent teaching EP 0 235 557 , the function of back and forth to ensure the winding of the wire spool, is performed by means of a grooved cam with double helix, to drive a trolley in translation, parallel to the axis of the coil. The carriage drives the wire before it is wound on the generator forming the coil. The direction reversals of the carriage at the ends of the cam allowing the movement back and forth, require a minimum mass of the carriage, to limit the consequent efforts at the time of reversal of direction.

To obtain this minimum mass, the element that transmits the movement between the cam and the carriage, is generally constituted by a pad, a part of which rubs within the groove formed in the thickness of the cam.

Such friction is a disadvantage when wire tensions and coil speeds are important, as it generates premature wear.

According to the patent teaching EP 0 453 622 , the function of back and forth is performed by means of a carriage whose wire is driven by a belt or a cable subject to at least one driving pulley. The change of the direction of rotation, to achieve the movement back and forth at the carriage, is achieved by reversing the direction of the pulley.

Such a solution imposes a sophisticated electronics for the realization of reversals of direction, given the very short time to perform such inversions, and the precision necessary for the positioning thereof.

It is also observed that the transmission elements such as the motor rotor, the belt, the pulleys, must undergo a reversal of direction, so that it is necessary to have a very low inertia of its components. elements, making them fragile when voltages and winding speeds are important.

Another solution emerges from the teaching of the patent US-A-3,716,200 wherein the reciprocating system comprises a carriage receiving a wire guide and having coupling arrangements with a flexible transmission and drive member mounted between deflection members. The wire guide is moved back and forth in combination with guide means in the form of a pin engaged in a groove formed in the thickness of a support plate.

From the state of the art defined in particular in this document US 3,716,200 ,

the problem to be solved by the invention is to perform a reversal of the direction of movement by simple mechanical guidance, positively and accurately and without friction.

To solve such a problem, it was designed and developed a winding device having the characteristics defined in the second part of claim 1.

Given the basic characteristics of the invention, the only inverted mass is that of the carriage driving the wire in translation.

To solve the problem of ensuring the drive in translation of the carriage, in a reciprocating motion, the flexible transmission and drive member is constituted by a toothed belt mounted between two toothed wheels, one of which less is rotated, the coupling arrangements of the carriage being secured to a portion of said belt so as to subject the reciprocating movement to contour tracking of the belt.

As a result, the winding is carried out, not on the basis of the inversion of the direction of the belt, but on the basis of the movement back and forth made by tracking the contour of this belt mounted between the gears.

To solve the problem of varying the yarn guide stroke and, consequently, the yarn removal stroke, the main axis of the trajectory described by the transmission and drive member, forms a angle with the linear guide axis of the carriage, so that the total stroke of the wire guide depends on said angle which is adjustable.

• la figure 1 est une vue en plan à caractère schématique du dispositif de renvidage selon l'invention ;
• la figure 2 est une vue en coupe transversale considérée selon la ligne 2-2 de la figure 1 ;

The invention is described below in more detail with reference to the figures of the accompanying drawings, in which:

• Figure 1 is a schematic plan view of the winding device according to the invention;
• Figure 2 is a cross-sectional view taken along the line 2-2 of Figure 1;

The figures of the drawings show the winding of a wire (F) on a spool (1) driven in rotation by a call cylinder (R) for example. In a known manner, the wire (F) is distributed by means of a wire guide (2) displaceable in translation, parallel to the generatrices of the support coil (1). The aim is to subject the wire guide (2) to a back and forth motion composed of a linear speed zone and two end zones of cusp, the shortest possible_

According to the invention, the winding device comprises a carriage (3) receiving the wire guide (2). This carriage (3) has coupling arrangements with a flexible transmission and drive member (4), adapted to impart to the thread guide (2) a back and forth movement in combination with translation guide means , parallel to the generatrices of the coil (1). The flexible transmission and drive member is advantageously constituted by a toothed belt (4) mounted between two toothed wheels (5) and (6), at least one of which is rotated.

For example, the toothed wheel (6) is rotated by a motor (7), while the toothed wheel (5) serves as a deflection- The belt (4) is tensioned between the two pulleys (5) and (6).

The coupling arrangements of the carriage (3) are secured to a portion of the belt (4) so as to subject the reciprocating movement to the contour of the belt. For example, the coupling arrangements of the carriage (3) with the portion of the belt (4) are constituted by a connection of the pivot type. This connection of the pivot type has, at least, an axis (8) carried by a yoke or flange (9) enclosing the cross section of the belt (4) - The axis (8) is positioned between two teeth of the toothed belt (4). The yoke (9) is connected, with articulation capacity, to the carriage (3), by means of, for example, a pivot axis (10).

Note that each of the toothed wheels (5) and (6) has an area corresponding to the removal of at least one tooth, in order to let the coupling pin (8) pass. The number of teeth of the wheels (5) and (6), the belt (4) and the positioning of the pivot type connection (8), (9) and (10) form multiples between them, so that each turn of the belt, the coupling and drive shaft (8) falls on a missing tooth.

The linear guide of the carriage (3) is effected by means of a pin (11) engaged in a rectilinear groove (12a) formed in the thickness of a support plate (12), in a manner parallel to the generatrices of the coil (1). The plate (12) can be in two parts (12b) and (12c) delimiting a free space (12d) inside which the carriage (3) is moved. By for example, the groove (12a) is formed in the thickness of the plate (12b) arranged in superposition of the plate (12c). The plate (12c) has a central slot (12e), oblong overall shape, for mounting and engagement of all wheels (5) and (6) and the drive belt (4).

Importantly, the wire guide (2), the guide pin (11) and the coupling pin (10) are angularly offset on the carriage (3), to create an additional speed component in the vicinity of the reversal points. In particular, the wire guide (2), the guide pin (11) and the coupling pin (10) are arranged along the three vertices of a triangle, advantageously but not exclusively, in the form of a right triangle. .

Given these provisions, the carriage (3) is L-shaped profile constituting two arms (3a) and (3b) angularly offset, substantially 90 °. The wire guide is arranged at the free end of the arm (3a), while the coupling pivot (10) with the belt (4) are arranged at the free end of the arm (3b). The guide pin (11) is disposed between the wire guide (2) and the coupling pin (10), at the connection of the two arms (3a) and (3b).

The point of attachment of the wire guide (2) to the arm (3a), (B) the point of attachment of the guide pin (11), and (C) the point of attachment of the coupling pivot (10). If we consider the example shown, we form a right triangle in (B). The distances (AB) and (BC) are determined to optimize the inversion times of the end (A). The distance between the points (B) and (C) is greater than the radius of the gears (5) and (6).

Given these provisions, it follows that the point (C) describes a path that follows the oblong contour of the drive belt (4) driven by the wheels (5) and (6). The point (B) is therefore translated along the groove (12a). Point (A) has a linear trajectory when point (C) is located between pulleys (dashed lines, Figure 1), while velocity component is added when point (C) passes from one side to the other of one of the wheels (5) or (6) at each end.

The two toothed wheels (5) and (6) are arranged along an axis (X-X ') forming an angle (α) with the groove (12a) in which the pin (11) moves. This angle (α) makes it possible to vary the stroke of the thread guide (2) and, consequently, the thread removal stroke. In these conditions, to make stroke variations, simply adjust the angle (α) by any known and appropriate means.

The advantages are apparent from the description, in particular it is emphasized and reminded that the transmission of the movement is effected without friction, the reversal of meaning being effected by simple mechanical guidance, so positively and accurately. The only inverted mass is that of the carriage driving the yarn in translation.

Claims (7)

1. - A device for winding a yam (F) on a holder (1) driven in rotation, the yam being distributed by means of a yam guide (2) capable of translational movement parallel to the generating lines of holder (1) which is driven in rotation, the device comprising a carriage (3) accommodating yam guide (2) and having connecting features of the pivot type (10) with a flexible drive transmission (4) mounted between two deflecting elements (5) and (6) which rotate around a shaft and are capable of subjecting said yarn guide (2) to a reciprocal movement in combination with means of translational guidance comprising a pin (11) engaged in a straight groove (12a) formed in the thickness of support plate (12) parallel to the generating lines of the rotating holder,
   characterised in that attachment point (A) of yarn guide (2), attachment point (B) of guide pin (11) and the attachment point of pivot (10) of the connecting features are angularly offset on carriage (3) as the three apexes of a triangle (A, B, C) viewed in a plane perpendicular to the axis of deflecting elements (5) and (6), translational guide pin (11) being located between yarn guide (2) and pivot (10) in order to produce an additional velocity component in the vicinity of the inversion points due to the effect of swivelling of carriage (3) by pivoting around guide point (B) during movement of attachment point (C) from one side of deflecting elements (5) and (6) to the other, guide point (B) being separated from attachment point (A) of yarn guide (2) and from attachment point (C) of holder (10) by equal or unequal distances determined so as to speed up the inversion times on yarn guide (2).
2. - A device as claimed in claim 1, characterised in that the translational guidance means and connecting features are located at the ends of two arms which are angularly offset by approximately 90° and constitute the carriage.
3. - A device as claimed in claim 1, characterised in that the flexible drive transmission consists of synchronous belt (4) mounted between the two components in the form of sprockets (5) and (6), one of which at least is driven in rotation, the connecting features of carriage (3) being joined to part of said belt (4) so as to slave the reciprocal movement to following the contour of the belt.
4. - A device as claimed in claim 3, characterised in that the features which connect carriage (3) to part of belt (4) consist of a pivot type link (10).
5. - A device as claimed in claim 4, characterised in that pivot type link (10) has at least one shaft (8) supported by a yoke (9) which grips the cross-section of belt (4), said shaft (8) being located between two teeth of the belt, the yoke being linked to the carriage and capable of articulation.
6. - A device as claimed in claim 1, characterised in that plate (12) consists of two parts leaving a gap (12e) inside which carriage (3) is moved).
7. - A device as claimed in claim 1, characterised in that the main axis of the trajectory travelled by drive transmission (4) forms an angle relative to the linear guidance axis of carriage (3) so that the total travel of yarn guide (2) depends on said angle which is adjustable.

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