GB669934A - Improvements in or relating to tire building apparatus - Google Patents

Abstract

669,934. Pneumatic tyres. FIRESTONE TIRE & RUBBER CO. Aug. 17, 1949 [Sept. 2, 1948], No. 21444/49. Class 144 (i). In tyre-building machines having stitchers capable of movement in more than one direction, e.g. axial and transverse to the axis of the building-drum, means are provided whereby (a) the angle between the stitcher and the drum is variable, as by linkage-mechanism, through continuous range of adjustment independently of other movements; (b) the stitcher is adapted for independent arcuate movement generally axially of the drum; and (c) the stitcher is adapted for independent dipping movement as a whole about a line parallel to its axial movement. Figs. 1 and 2 show the general layout of the stitcher mechanism with the stitchers 13, 14 in different positions on the work at opposite ends of the drum 10, the mechanism being mounted on a slide which is movable towards and from the drum by means of a hand wheel and rack-gears. Progress of the slide during the actual stitching operation is effected by power-driven means shown in Fig. 10. Arranged for engagement with the hand wheel 20 are driven high- and low-speed frictionwheels 25, 26 and a reverse-drive wheel 27, the selective engagement being controlled by hand levers 34, 44a. Relative adjustment of the stitchers is effected from a shaft 49 having oppositely-threaded ends carrying travelling nuts 56 which are pivoted on arms 54 connected to the stitchers by parallelogram linkage comprising links 61 rigid with the fixed arms 54 so as to determine the position of the working- points 60 of the stitchers. Tilting of the stitchers is effected by swinging about a cross-shaft 49 by means of cranks pivoted on an angularly-adjustable rod 81 journalled on the stitcher-table. For co-ordinating mutual approach and independent orientation of the stitchers, a bell-crank lever pivoted on a bracket 98 on the stitcher-table has one arm 99 pivoted to a tie-rod 100, the other end of which is attached to the lever 88 which controls the stitcher-actuating linkage. The other arm 101 of the bell-crank is positioned for engagement by a lug on a slide 103 adjustable along the hand lever 64. The slide is so positioned on the lever 64 that after operation on the plies over the rounded edge 104 of the drum, the lug clears the arm 101 and the stitchers then maintain a constant angle with respect to the drum.