| 摘要 |
<p>A pneumatic device having a selectively variable pneumatic output comprises an inlet connectable to an air source and an outlet disposed in a flow path, a control assembly in the flow path and having a plurality of differently sized primary orifi. The control assembly includes a selector having a secondary orifice, the selector moveable relative to the primary orifi between a plurality of positions, the primary orifi and the secondary orifice arrangeable relative to one another to permit the secondary orifice to be in flow communication with a selected one of the primary orifi. The control assembly further blocks the remaining primary orifi when the secondary orifice is aligned with the selected one of the primary orifi.</p> |
