| 摘要 |
A pump apparatus comprises a pump head and a container for a liquid to be dispensed. The pump head has a flexible dispensing tube in fluid connection with the inside of the container. The fluid in the container in being sterilized results in pressure build up which needs to be released. The fluid connection between the dispensing tube and the inside of the container is provided by a supply tube which co-operates with the dispensing tube to provide a simplified non-return valve function that allows pressure release when the liquid in the container is sterilized with consequent elevated temperature and pressure. An end of the supply tube is disposed within an end of the dispensing tube and the non-return valve function is provided by a hole through a side wall of the supply tube in a region where the dispensing tube overlaps the supply tube, whereby the dispensing tube is forced away from the supply tube for pressure release when the internal pressure increases and is brought back to provide a seal over the hole to prevent ingress of fluid when the internal pressure is lower than the external pressure. |
