| 摘要 |
<p>A tire inflation valve stem comprises a stationary, radially outer stem part (3); a movable, radially inner stem part (4) slidable axially within the outer part; a compression reaction spring (20) extending between the core parts; and a flexible barrier (23) extending from one core part to the other to prevent air leakage between the parts. The flexible barrier comprises a thin walled, soft elastomeric tube sealed at its ends to the respective core parts and with an intermediate part curved back on itself in a free rolling manner within a variable length annular space between an external cylindrical surface (19) of the movable core part and an internal cylindrical surface (12) of the stationary part.</p> |
