| 摘要 |
<p>A lip seal (12) serving as a gap sealing part for selectively sealing only a flow of fluid in the downstream direction while a sliding gap (G1) in which a fixed shaft part (8a) fits into a fitting hole (7a) provided in a housing member (7) allows axial movement of the fixed shaft part (8a), is provided in said sliding gap (G1). A narrowing part (18) provided at a narrowing hole (18c) which has a flow path diameter (d2) smaller than the flow path inner diameter (d1) of a fixed flow path (8f) and is provided upstream of the end part of the fixed flow path (8f) is also provided in the sliding gap (G1). As a result, fluid flowing downstream through the narrowing part (18) generates a differential pressure, whereby the fluid within the sliding gap (G1) is made to flow to the fixed flow path (8f), and is discharged along with contamination (20) in the fixed flow path (8f).</p> |
