| 主权项 |
1. A tyre inflation feed arrangement for a tyre supported on a wheel carried by a wheel rim rotatably mounted via a wheel hub on an axially outer end of an axle housing, the feed arrangement comprising a annular support body surrounding the outer end of the axle housing, three concentric annular seals extending around an axially outwardly facing surface on the support body to seal two concentric annular chambers formed in the axially outwardly facing surface between the seals, a first of said annular chambers being connectable with pressurised air to inflate the associated tyre and the second annular chamber being connectable with pressurised air to operate a valve mounted on the wheel for admitting air into the tyre from the first annular chamber or exhausting air from the tyre, the annular seals each being mounted in a respective annular groove in said axially facing surface and each groove also being connectable with a source of pressurised air to press said seals against an annular contact surface on the wheel hub to seal the first and second annular chambers when the tyre is being inflated, the wheel hub being provided with a first passage which opens through the annular contact surface to receive air from the first annular chamber and conduct such air to the tyre and a second passage which also opens through the annular contact surface to receive air from the second annular chamber and conduct such air to the valve mounted on the wheel, the support body being mounted on the axle housing in a location radially within bolts which attach the wheel to the hub to reduce the rubbing speed of the seals on the contact surface to reducing wear caused by the contact pressure of the seals. |
