ES344203A1 - Improvements in Winding Apparatus - Google Patents

Abstract

A winding machine for winding threads, yarns or tows into crosswound packages has its traverse formed by two yarn guide arms 34, 41 which rotate in opposite directions about two parallel axes over a yarn guide 52. The arms 34 and 41, during rotation, alternately project beyond the contour of and retract behind the yarn guide 52, see also Fig. 3 not shown. The arms 34 and 41 and bobbin shaft 6 are driven at a predetermined relative speed by a progressively variable gear 91, 93 the gear ratio increasing in response to the increasing radius of the package by means of a feeler member (e.g. bobbin support 70) coacting with the growing package. The winding speed can thus be kept constant or progressively increased. As shown in Figs. 6 and 7, yarn 62 is passed through tension device 63, past stop motion 64 over the thread support 65, then engaged by the oppositely rotating thread guide arms 66, over supporting shaft 99 and wound onto the package 67. Traverse mechanism: The oppositely rotating arms (labelled 34, 41 in Fig. 1 and 66 in Figs. 6 and 7) are rotated on offset axes by a shaft (32) and eccentric sleeve (38), see also Figs. 2 to 5 not shown. Thereby, as the thread approaches the end of one traverse, the rotating arms are radially displaced slightly and the thread slips easily from one arm to the other which moves it in the opposite direction. The drive to the rotating arms is taken from a common shaft 21 which, in Fig. 1, also drives the bobbin spindle. In Fig. 6 the spindle and common shaft are both driven by a single toothed belt. The arms and the rotational speed of the bobbin can be reduced as the package grows, (see below). Preferably projections of contours swept by the rotating arms onto a generatrix of the package are of identical length. The thread support (labelled 52 or 65 in Fig. 1 and 6 respectively) can have a straight or curved edge so as to produce differently shaped packages. Spindle and rotating arms drive is taken from motor 71 via belt 72, drum 80, shaft 79, drum 81, through belt 93 to friction disc 91 thence to the common spindle and rotating arms drive (see above) via gear 92, belt 74 and pulleys 75 and 76. As the package grows the rockable arm 70 moves clockwise and this motion operates via linkages 98 to move a toothed sector 97, and thus pulley 95 and belt 93, to the right. The rightward movement of belt 93 lowers the gear ratio between drum 81 and friction disc 91 and thereby reduces the speed of the bobbin and rotating arms. Stop motion: When device 64 detects a break in the yarn a pin 89 (Fig. 7) causes segment 87 to be coupled with rotating shaft 79 and control shaft 86 thereby pivoting the friction disc 91 away from belt 93 into a neutral position thus interrupting the spindle drive. End finding: Simultaneously with the interruption of the spindle drive on rotation of control shaft 86, an upper cam 107 connected to control shaft 86 also rotates thereby causing its cam follower to (a) swing suction nozzle 110 upwardly to the package and (b) rotate rocking arm 70 so as to lift the package off supporting shaft 99, Fig. 6. Meanwhile the continued rotation of the lower cam 100 depresses its cam follower still further and thus engages the friction disc 91 with rotating cone 90. This cone drives the friction disc 91 and the package in reverse to unwind the thread which then is sucked into nozzle 110. On further rotation of control shaft 86 and its cam 100 (a) a pawl (123) (Figs. 9 and 10 not shown) acts on notched segment 87 so as to disengage rotating coupling 85 from shaft control 86, and (b) cam 100 pivots the friction disc 91 away from rotating cone 90 and cam 107 returns the nozzle downwardly. Recommencing winding: The thread held in suction tube 110 is knotted and the attendant depresses foot pedal 124 (Fig. 6). This releases the pawl (123) and recouples control shaft 86 with rotating coupling 85. Cams 100 and 107 are thereby rotated to their operating positions in which friction disc 91 is returned to press against revolving belt 93 and package 67 is lowered onto shaft 99. Cams 100 and 107 are stopped in the operating position by the decoupling of shaft 86 from rotating coupling 85 by the engagement of notched segment 87 with pin 89.