| 摘要 |
<p>An improved valve assembly is disclosed for use in a vacuum system. The valve assembly is provided with a valve which is movable between a first position and a second position. In the first position, the vacuum reservoir is isolated from the vacuum pump. In the second position, the valve permits air to flow from the vacuum reservoir to the vacuum pump only through metering ports. The valve assembly reduces the horse power requirement for initial start up of the vacuum system by restricting air flow from the vacuum reservoir to the vacuum pump. Also, an immediate vacuum is created in the valve assembly on start up to return oil from a separator to the pump.</p> |
