| 摘要 |
<p>A pressure-controlled three-way valve device for inflating, keeping inflated and deflating tires, the device having a plunger (21) axially traversed by an inlet passage normally closed by a spring-urged inlet valve. The plunger's outer s'idewall has a recess in which an O-ring (37) extends to abut against the steps (41A,41B) of the recess to limit the plunger stroke and keep an outlet circuit (15B) closed to a venting port (17B) formed in the sidewall of the body of the device. The plunger moveing between a position to open air supply to the tyre, a position to keep an outlet circuit to a tyre closed and a position to open a venting port to deflate the tyre. The plunger being mounted into the valve body (13) by a diaphragm (43) sealing an outer wall of the plunger against the valve body and permitting the moving of the plunger with minimal friction between the plunger and the valve body.</p> |
