Tyre building drum with turn-up mechanism

摘要

Tire building drum having a turn-up mechanism for use in building an unvulcanized tire using rubber tire components, having two sets of turn-up arms (14), wherein each set of arms is connected to an axially shiftable arm support (17). The tire building drum is provided with means on the one hand for shifting the arm supports in a first direction to move the sets of turn-up arms axially towards each other, wherein the arras are tiltable in radial planes from a starting position to a tilting position, and on the other hand for in a second direction, opposite the first direction, shifting the arm supports to move the arms axially apart from the tilting position into the starting position. The tire building drum is provided with a pneumatic detection device (20) (23) for detecting whether at least one of the moving parts, such as the arms or the clamping device, are in the starting position, and for giving a detection signal indicating whether or not the arms are in the starting position.

主权项

1. Tyre building drum with turn-up mechanism for use in building an unvulcanised tyre using rubber tyre components (t), with two bead cores (b), wherein the tyre building drum is provided with:
a central drum shaft (1); two ring segments (13) placed around the shaft and spaced apart from each other, for supporting the bead cores (b); an expansion device for radially expanding the part of the tyre components situated axially between the ring segments; two sets of, in a correct starting orientation, axially extending arms (14) that are placed on either side axially outside of the ring segments with respect to the center of the tyre building drum, wherein at a first free outer end oriented towards the ring segments the arms of each set are provided with a respective first turn-up members (11), and wherein all arms of each set, at an opposing second outer end, are hinged to a respective axially shiftable arm support (17), common to the set in question, a shifting device for shifting the arm supports (17) axially from respective axial home position in respective first directions to the center of the tyre building drum to move the second outer ends of both sets of arms (14) axially towards each other, wherein the arms are tiltable in radial planes from the correct starting orientation to a tilting orientation for as a result axially and radially moving the first outer ends while pressing a part of the tyre components which is initially situated axially outside of the ring segments with respect to the center of the tyre building drum against the expanded part of the tyre components situated axially within the ring segments, and for shifting the arm supports (17) axially in respective second directions, opposite to their respective first directions, to their axial home position to move the arms (14) axially apart from the tilting orientation to the starting orientation, characterised in that the tyre building drum is provided with a detection device for detecting whether at least one of the arms of one of the sets of arms of the tyre building drum is correctly axially extending in the starting orientation when the associated arm support of the one set has been shifted into its axial home position, wherein the detection device comprises compressed air source (23) and an air channel (20) connected or connectable with the compressed air source, wherein the air channel comprises an opening (k2), and wherein the at least one of the arms (14), at least in or near the starting orientation, is coupled to the opening for adjusting or changing a flow and/or a pressure in the air channel, wherein the detection device furthermore comprises a flow meter (F) for measuring the flow in the air channel, wherein the at least one of the arms (14), when correctly axially extending in the starting orientation, is arranged for sealing off a contact surface of a stop part (22), wherein the air channel debouches via the opening (k2) on or in the contact surface of the stop part, wherein the detection device furthermore comprises a safety bush with a prestressing spring, wherein the safety bush is moveable between a closed position in which the safety bush is pressed against the contact surface in a substantially sealing manner by means of the prestressing spring and an open position in which the safety bush is moved out of sealing contact with the contact surface, and wherein one arm of the at least one of the arms (14), at least in or near the starting orientation and when its associated arm support (17) is in the respective axial home position of that arm support (17), abuts the safety bush for controlling the movement of the safety bush between the closed position and the open position, wherein the one arm of the at least one of the arms (14), when correctly axially extending in the starting orientation and when its associated arm support (17) is in the axial home position of that arm support (17), abuts the safety bush in a manner so that the safety bush remains in the prestressed closed position, and, in an incorrect orientation abuts the safety bush in a forceful manner to move the safety bush to the open position.