| 摘要 |
<p>The pump has a regulating element (31) provided on a cover (2). A channel is associated with ambient air via two channels, so that air in an oil receiving chamber (11) is vented from an air outlet (232) of one of the two channels, to produce suction power, during an oil suction process. Another channel is associated with ambient air via the former channel and an air inlet of a third channel, so that air enters the chamber via a through hole of the former channel to produce pressure for pumping down oil, during an oil pumping down process.</p> |
