Pressure controlled chamber

摘要

A pressure controlled chamber arrangement comprising a chamber, one or more seals arranged in use to limit fluid flow between the inside and outside of the chamber and a vent system arranged in use to remove a vent flow of fluid from the inside of the chamber. The vent system at least contributes to the formation of a pressure drop across the one or more seals from the outside to the inside of the chamber. The vent system comprises a flow controller arranged in use to control the quantity of fluid removal via the vent system in accordance with the sealing performance provided by the one or more seals, the vent system giving increased quantity of fluid removal for decreased sealing performance.

主权项

1. A pressure controlled chamber arrangement comprising:
a chamber; one or more seals arranged in use to limit fluid flow between the inside and outside of the chamber; and a vent system arranged in use to remove a vent flow of fluid from the inside of the chamber and at least contribute to the formation of a pressure drop across the one or more seals from the outside to the inside of the chamber, the vent system comprising a flow controller arranged in use to control the quantity of fluid removal via the vent system in accordance with the sealing performance provided by the one or more seals, the vent system giving increased quantity of fluid removal for decreased sealing performance, wherein: the flow controller controls the quantity of fluid removal using a control fluid flow taken from a source giving a control fluid flow pressure proportional to the pressure around the seals external to the chamber, and the flow controller is a vortex device in which the control fluid flow and the vent flow are combined such that the control fluid flow generates a vortex that inhibits passage of the vent flow through the vortex device.