Patent ID: 8113060

Claim:
A pressure sensing device configured to permit a liquid to flow there through and to sense the pressure of said liquid, said device comprising: a casing being fluid-tightly divided into a first and a second chamber by a flexible, impermeable wall, said first chamber having a first opening for the liquid, said first opening being placed at the lower part of the chamber, said first chamber having a second opening for the liquid, said second opening being placed at the upper part of the chamber, said second chamber having a measuring port, connectable to a pressure transducer for bringing the second chamber into gas-tight communication with the pressure transducer, wherein the second opening for the liquid being is placed at the top of the first chamber, a first orifice for permitting the liquid to flow into and out of the device is placed at the upper part of the device at a higher level than the second opening of the first chamber, a first channel connects the first orifice of the device with the first opening of the first chamber, a second orifice for permitting the liquid to flow out of and into the device is placed at the lower part of the device at a lower level than the first opening of the first chamber, a second channel connects the second opening of the first chamber with the second orifice of the device, wherein the highest level of the first chamber is at the same level as or at a higher level than the highest level of the second channel, and a first duct is provided having a lower mouth and an upper mouth, said lower mouth being placed in the top of the first chamber and the upper mouth being placed in the first channel at a higher level than the lower mouth.