| 摘要 |
A sealing arrangement for trocar tubes including an upper ring seal forming the primary seal, and a lower seal valve forming the secondary seal. Both seals form part of a valve system which can be positioned within a removable cartridge. The valve cartridge comprises a tubular open-ended housing in which the seal ring is fitted to the top opening, and with the seal valve located within the housing. The seal valve is elastomeric in tubular form for passing instruments and is provided with upper and lower flanges for placement within the cartridge. The intermediate portion of the valve between the flanges is in the general form of converging and diverging frusto-conical sections which join along a sealing line. A seal is formed between the interior wall surfaces of the valve and the instrument present in the trocar tube. Peritoneal pressure is admitted to the trocar head or housing for pressing the valve in forming the desired seal. With the instrument removed, the valve walls engage each other along the seal line to form the desired seal. The valve walls are layered with hydrogel and a microencapsulated liquid coating substantially extending the shelf-life of the valve, providing lubricity for the valve surface, and improving the sealing characteristic of the base elastomer of the valve body.
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