GB784769A - Improvements in bead wrapping machine - Google Patents

Abstract

784,769. Tyre-bead wrapping machines. UNITED STATES RUBBER CO. Nov. 28, 1955 [Dec. 13, 1954], No. 33981/55. Class 144 (1). In a machine for wrapping a length of rubber tape T around a bead wire bundle B, the bead B is positioned around a wheel 10 comprising axially-spaced radial flanges 10a, 10b between which is resiliently mounted a member 27a forming a radially inwardly displaceable base so that under localized pressure during wrapping of the tape, a segment of the bead B is received wholly between the flanges 10a, 10b. As shown, the wheel 10, Fig. 4, is mounted on a motor-driven shaft 11 and comprises the two flanges 10a, 10b which are screwed together to leave an axially adjustable annular outer peripheral space therebetween. Within this space is mounted an annular disc 27 bonded to one lateral face of a rubber ring 28, the other lateral face of which is bonded to a ring 29 secured to the flange 10a. An outer peripheral axial flange 27a on the disc 27 forms the resilient base to the annular space between the wheel flanges. The rubber tape T is fed from a stock roll 42, Fig. 1, over pulleys 46, 47, through a perforating clamp 50, around an adjustable pulley 52, pulleys 57, 59, and over guide rollers 61 and 63 on to the periphery of the wheel 10 against which it is pressed by a roller 30 under the action of a solenoid 86, the feed of the tape T being by friction with the wheel 10 under the pressure of roller 30. A separate motor-driven pulley 97 is provided to assist take-off from the stock roll 42. A series of pressing and stitching rollers 31, 33, 35, Fig. 2, interspaced by folding ploughs 32, 34 are mounted on an arcuate support 36 carried by a slide 37 for movement towards and away from the periphery of wheel 10, movement of the slide 37 being effected by a piston and cylinder arrangement 40, 40a. In operation, the bead B, which is of larger diameter than the wheel 10, is suspended on a pin 111, Fig. 3, so that a segment of the bead embraces the periphery of the wheel 10. With the slide 37 in operative position, the tape T is fed onto the periphery of wheel 10 to lie beneath the bead B. As the wheel 10 rotates the bead B is forced by the roller 31 into the space between the wheel flanges 10a, 10b, against the flange 27a of the resiliently-mounted ring 27, causing the tape T to be wrapped around three of the four sides of the bead section, Fig. 5. On further rotation, the ploughs 32 and 34, and stitching rollers 33, 35, successively act to fold and stitch first one projecting edge of the tap over the remaining side of the bead section, and then the other edge of the tape to lap the first edge, Fig. 9. Towards the completion of the wrapping operation, the solenoid 86 is operated to permit retraction of the roller 30 under the action of a spring 91, Fig. 4, and a solenoid 102, Fig. 1, is actuated to operate the perforating clamp 50 to clamp and transversely perforate the section of tape passing therethrough. The tension thus imposed on the tape between the clamp 50 and the wheel 10 causes the tape to tear at a previously perforated portion which now lies on the periphery of wheel 10 at a point between the rollers 30 and 31. A spring-pressed brake finger 95 acts on the tape to prevent rearward movement of the stock portion lying rearwardly thereof and thus when the roller 30 is re-applied to the wheel 10 the tape will be pulled forward for application to a new bead without any intervention by the operator. The actuation of the solenoid 102 is controlled by a switch 210 operated by a cam 65 driven through a variable-speed mechanism 58 coupled to the tape pulley 57, so that by adjustment of the pulley 52, and the mechanism 58, the length of tape between successive perforations can be set to the required amount for a given diameter of bead. Operation of the switch 210 effects also operation of a solenoid valve to admit pressure fluid to the cylinder 40 and cause retraction of the slide 37. During retraction, a cam 119 on a bracket 118 carried by the slide 37 contacts a block 117 mounted on an ejection arm 112 to cause outward swinging of the arm about its vertical pivot 113 so that a block 112a carried by the arm 112 and slidably sleeved over the bead supporting pin 111 forcibly ejects the wrapped bead from the machine. The Specification describes an arrangement of limit switches and relays for the fully automatic operation of the machine during each wrapping cycle on operation of a single press-button switch after each manual loading of a bead wire bundle to be wrapped.