Patent ES-251306-A1 (ES)
Title: Apparatus for conveying and joining lengths of rubberised fabric
IPC: B29D30/38
Filed: 1959-08-06
Abstract: Lengths of rubberized fabric, e.g. bias-cut plies for tyre-building, mounted on a main conveyer are joined and the joined lengths are removed therefrom by intermittently conveying single lengths of the fabric successively to a joining position, joining a marginal portion of a length of fabric to a marginal portion of a preceding length of fabric previously withdrawn from the main conveyer and supported in a position so that a marginal portion is overlapped by a marginal portion of a succeeding length when conveyed into the joining position, and intermittently withdrawing the joined lengths so that an unjoined marginal portion of a joined length remains in the joining position. A sheet of rubberized parallel-cord fabric 10, Fig. 1, mounted on a main conveyer 1 consisting of four narrow endless belt conveyers 2, is bias-cut by a circular knife 15 mounted in mechanism 12, 14, the severed length of material 21 is conveyed to the position shown in Figs. 1 and 2 at which one margin 21a overlaps a margin 24a of a continuous strip of fabric 24 on a conveyer 22 preferably disposed to the side of conveyer 1 and parallel to the knife mechanism 12, 14, the margins are joined by operation of a clamp mechanism 23 above a bar 37 on a table 25 and the continuous strip 24 is withdrawn until the margin 21d of the severed length reaches the joining position of the clamping mechanism. Orifices beneath conveyer 1 and table 25 provide for "air flotation" of the fabric. The leading edge of the advancing fabric is arranged to interrupt light to two photo-electric cells 16, 17 (Fig. 7, not shown) for the actuation of electrical circuits respectively for slowing down conveyer 1 and later for disengaging pressing rollers 6 and for operating a vacuum clamp 11 to hold the on-coming fabric stationery the conveyer 1 continues moving until a previously cut ply 21 is adjacent to the take-off conveyer 22, when the conveyer is stopped and the knife 15 is drawn across to sever a <PICT:0922693/IV(a)/1> <PICT:0922693/IV(a)/2> <PICT:0922693/IV(a)/3> further length of fabric. Conveyer 1 is restarted and after a short, predetermined interval, sufficient to allow a gap 10c to be formed between the severed ply and the remainder of the fabric, the fabric is released from the clamp 11 and the rollers 6 are re-engaged to drive the fabric on the conveyer. The clamp mechanism 23 (see Fig. 4) consists of a bar 27 carried by arms 28 mounted on a rotatable shaft 29 pivotally supported at its ends in brackets 30, 31 attached to the table 25 and disposed parallel to the longitudinal direction of conveyer 1 the bar 27 may alternatively be held in a raised position or lowered by operation of a pneumatic piston and cylinder 36 and pressed downwards on to the margins of the fabric to be joined. The clamp mechanism 23 is maintained in the required position relative to the edge 21a of the ply 21 by sliding adjustment of the table 25 towards or away from conveyer 1 on bearings 38 by the engagement of a rotatable lead screw 42 with a screw-threaded nut (not shown) attached to the table. An aligning bar 47, provided with holes 48 connected to vacuum and slidable in a recess 49 of the table 25 by operation of a rotatable lead screw 50 engaging with a screw-threaded block 51, ensures that the lateral edges 24b and 24c of the strip 24 are in alignment with the corresponding edges 21b and 21c of the ply 21 when in the joining position. The apparatus for clamping the plies 21 to the strip 24 and for operation of the take-off conveyer 22 is controlled by five photo-electric cell units 56-60 (see Figs. 2 and 6). The cell unit 56a, 56b is provided for stopping conveyer 1 and for causing the clamping mechanism 23 to operate when the trailing edge 21c of a ply 21 crosses its optical axis cell unit 57a, 57b, is for slowing down the take-off conveyer 22 when the edge 21d of the ply crosses its optical axis cell unit 58a, 58b, is for stopping the take-off conveyer when the edge 21d has just passed the bar 37 cell unit 59a, 59b, 59c, 59d, is for causing the position of the end 24a of the strip 24 to be adjusted, if necessary, by the aligning bar 47 after the take-off operation is complete cell unit 60 is for causing the table 25 to be moved towards or away from the conveyer 1 during <PICT:0922693/IV(a)/4> <PICT:0922693/IV(a)/5> operation of the take-off conveyer, to ensure that the overlap of the margin 21a of the ply 21 above the margin 24a of the strip 24 is of a predetermined size the cell unit 60, which comprises two light sources 60a, 60b and associated photo-electric cells 60c, 60d, respectively (Fig. 3, not shown) differs from cell unit 59 in that both the light sources and cells are mounted above the conveyer surface, the surface of the conveyer 1 immediately beneath cell unit 60 being provided with a polished aluminium plate. The cell units which are fitted in sliders aligned to the respective conveyers 1 and 22, are connected to electronic control apparatus (not illustrated). The knife track 14 is carried by a framework 84, Fig. 10, supported on a turntable 85 mounted beneath the conveyer 1 on a trolley 86 drivable through pinion 89 in the longitudinal direction of the conveyer. Adjustment of the angle which the track 14 makes with the longitudinal direction of the conveyer 1 is effected by rotation of the turntable 85 by means of a motor 94 drivably connected via a gear-box 96 and a pinion 96a to a toothed quadrant 97 attached co-axially to the turntable 85 in this manner the width and bias angle of the plies 21 may be varied. The angle at which the conveyer 22 is orientated with respect to conveyer 1 and the position of the cell units 16, 17 may be correspondingly changed (Fig. 5, not shown). The strip 24 is reeled-up on a spool 126 started and stopped, as determined by photo-electric cells 135 and 136 (Fig. 5, not shown), when a loop of fabric 24d formed between the take-up conveyer and the spool exceeds or does not exceed, respectively, a predetermined size. The framework 26 on which the spool 126 is mounted is adjustable transversely, under the control of a cell-unit 127 (Fig. 9, not shown), with respect to the take-off conveyer 22 for centralizing the strip 24 on the spool.