Tyre for four-wheel drive vehicles - has construction with belt and with additional circumferential elastomer sheet to absorb shocks, stiffen sides and improve braking effect

摘要

A tyre, partic for four-wheel drive vehicles, has a toroidal body with two sidewalls and beads, a tread, a belt of at least two layers, and a radial carcas of at least one layer. The main body contains at least one embedded sheet or elastomer to provide a circumferential shock-absorbing effect and to stiffen the sides; by this means the damping effect of the tyre wrap as measured by the ratio of centre force to hysteresis force is between 0.1-0.25, and the stiffness of the wrap is at least 60000 daN. The tyre has an air-tight inner sheet (1), a carcass (2) of at least one layer which is wrapped round the two bead cores (3), two sidewalls (4), a belt of at least two layers (5) and the profiled tread (6). The essential component of the invention is a circumferential member (at least at places) to produce shock absorption. This delays the response time between applying the brakes and their translation onto the road. Under transverse loads such as when travelling round bends, this also stiffens the tyre wrap laterally so as to keep short the time of response to steering forces. ADVANTAGE - The system enables the tyres to reduce the costs of producing controlled braking effect on four-wheel drive vehciles.