| 摘要 |
<p>An assembly that converts a standard cylinder outer head, having a clearance passageway formed therewithin, to a fixed volume clearance pocket outer head. The assembly comprises a gate valve having cooperating butterfly-shaped plates or elements operative, across the innermost portion of the clearance passageway of a standard cylinder outer head, by a rotatable valve shaft-engaging collar disposed external of the passageway.</p> |
