| 摘要 |
A measuring device is disclosed for measuring an ultra low gas flow, working by the principle of liquid displacement. In at least one embodiment, the measuring device includes at least one cell including a gas inflow device, a gas compartment device with a predefined inner geometric physical volume and active volume. In at least one embodiment, the gas compartment device includes one gas accumulating end and one lifting end, the gas compartment device also defining a geometric gas collecting point inside of the gas compartment device, during a gas filling cycle, the geometric gas collecting point moving further and further from the gas accumulating end to the lifting end during the gas filling cycle. Further, in at least one embodiment the cell includes a holding device having a pivoting element enabling the gas compartment device to pivot upwards when the geometric gas collecting point is positioned at the lifting end and the lifting force is larger than the down-pressing force at the lifting end, thereby releasing all of the accumulated gas in the gas compartment device, and then pivoting back to its initial standby position for new receipt and storage of gas during another gas filling cycle until next releasing sequence. Finally, in at least one embodiment, the cell also includes a sensor provided to generate a signal and/or change the state of a signal when the gas compartment device is not in its initial standby position, wherein the gas storing capacity of the inside of the gas compartment device is larger at the gas accumulating end than at the lifting end and wherein the gas accumulating end has a higher vertical position than the lifting end at the initial standby position. |
