Patent GB-841880-A (GB)
Title: Method and apparatus for forming tire bead cores
IPC: B29D30/48
Filed: 1957-11-20
Abstract: 841,880. Making tyre-bead cores. FIRESTONE TIRE & RUBBER CO. Nov. 20, 1957 [Dec. 3, 1956], No. 36123/57. Class 144 (1). A tyre-bead core of spirally-wound ribbon, as described in Specification 802,253, having its radially inner terminal portion 4, Fig. 9, stitched flat to one side surface of the core, is formed by supporting a segment of the core with one side resting on a table 15 and its radially inner and outer surfaces clamped between arcuate mating jaw surfaces 17, 22 so that the inner terminal portion 4 of the core ribbon is supported to extend laterally from the unsupported side of the core, and then bending and pressing the said end 4 flat on to the unsupported side of the core, as by a downwardly and outwardly movable presser head 34, with sufficient force to effect the desired stitching. As shown, the stitching is effected by an apparatus comprising an inclined core-supporting table 15 welded to the upper edges of vertical, laterally spaced, frame plates 13, 14 carried by two columns 11, 12. A fixed clamping jaw plate 16 having an arcuate clamping surface 17 is bolted to the top of the table 15, and a movable jaw plate 21 having a complementary clamping surface 22 is slidably mounted on the table between guides 18, 19. The plate 21 is movable by the piston 24 of a fluid-pressure cylinder 23 bolted to the table 15, and has a recess 27 in its upper face adjacent the clamping surface 22 to provide an inclined ramp 28 to support the free inner end 4 of the core ribbon when the core is clamped between the surfaces 17, 22. The said end 4 extends along the ramp 28 to rest on a block 31 fixed in a groove 32 in the plate 21, the groove 32 serving to guide a spring-loaded push-rod 33 operable to move the core end 4 to overlie the unsupported core side. The push-rod 33 is operated by a lever 46 which bears on the inner end of the rod 33 and is pivotally carried on one, 37, of a pair of press arms 37, 38 which are pivotally mounted on a pin 39 and are pivotable thereabout by a piston and cylinder arrangement 43, 44. The press arms 37, 38 carry an adjustable press head 35 to which a press block 34 is eccentrically pivoted to assume a position normally facing downwardly and outwardly so that as it is swung by the press arms 37, 38 towards the core end 4 its inner edge will first contact the plate 21, Fig. 16, and cause the block to pivot and flatten the core end on to the core side. The lever 46 is arranged to effect operation of the push-rod, Fig. 14, on initial movement of the press arms 37, 38 to position the core end 4 ready for flattening by the press block 34, Fig. 18. When the movement of the push-rod is arrested by abutment of a shoulder 40 thereon with the block 31, the subsequent movement of the press arms 37, 38 is permitted by a spring 47 loading the lever 46. A back-up block 54 for the press block 34 projects through an aperture 55 in the table 15 and is urged upwardly by a spring 56 against which the block is depressed on operation of the block 34. A recess 60 is the back-up block 54 and receives any portion of the edge of the core end 4 which may project beyond the core side on flattening. After the stitching operation, with the press block 34 and clamp plate 21 retracted, the core is ejected by pins 62 which are projected upwardly through holes in the table 15 against springs 63 by fingers 68 which are mounted on a shaft 67 rockable by a piston and cylinder arrangement 65, 64. Complete ejection is then effected by arms 71 normally received in slots 72 in the table and mounted on a shaft 73 which is rotatable against a spring 79 by a retractable piston 76 which is coupled to a chain 77 engaged round a sprocket 78 on the shaft.