| 摘要 |
<p>The instrument has a sealing piece (45) sealed against inner wall of a connecting shaft (33). The sealing piece is movably supported between an inserted sealing position and an extended rest position. The shaft comprises a ventilation opening (61) that is connected with a section (59), which is provided downstream of the sealing piece of the shaft, when the sealing piece is removed from the sealing position up to the ventilation position that lies between the sealing position and a starting position. The section is separated from the ventilation opening in the sealing position.</p> |
