Improvements in or relating to machines for preparing worn pneumatic tyres for retreading.

摘要

1,155,187. Roughening &c tyres. H. TIES. 26 Sept., 1966 [25 Sept., 1965], No. 42925/66 Heading B4B. In a machine for preparing a worn pneumatic tyre 2 for retreading in which the tyre is supported in the machine frame 1, Fig. 1 (not shown), between a pair of axially movable rim plates (4, 5) rotatably driven about a horizontal axis, two roughening tolls or rasping knives 10, 11 are journalled on a support 14 pivotable about an axis 15 intersecting the tyre centre 3a, the tools being radially adjustable towards the centre of the tyre and being pivotable about axes of the support and coupled in such a manner that their radial and their pivotal movements are homologously equal. The slipport is provided with guide rods 14a for two slides 17, 18, is pivoted about a pin 19 and carried by a disc 20. The slides carry pins 21, 22 on which are supported housings 23 for the tools 10, 11. One housing is provided with a control housing 24 which carries switches and operating buttons. Means are provided to change the spacing between the pins 21, 22. The control housing 24 carries a handle 29 for adjusting the radial distance of the tools 10, 11 from the centre of the tyre. This adjustment is effected by a motor drive (30), Fig. 3 (not shown) via a threaded spindle (31) with threads of opposite hand. The handle is provided with controls for switching on the motor (30). The pivotal movement of the support 14 is infinitely variable and arrestable corresponding to the clamped profile size of the tyre, the pivot position being readable on a scale.