| 摘要 |
A pump with a continuous inflow and a pulsating outflow comprises a first chamber and a second chamber with a passage between them and made at least partly from a flexible material. There is an inlet to the first chamber and an outlet from the second chamber. The passage between the chambers has a one-way valve permitting flow only in a direction from the first to the second chamber. A second one-way valve located at the outlet permits flow only in a direction out of the second chamber. The chambers are movably supported in a pump casing having a first and a second opening. The inlet is connected to and penetrates the first opening, and the outlet is connected to and penetrates the second opening. A drive arrangement reduces the volume of the second chamber to expel the pumped medium while simultaneously enabling the walls of the first chamber to increase the volume and permit the pumped medium to flow through the inlet into the first chamber. The drive means includes a drive ring surrounding the passage and fixed to it, which drive ring has surfaces engageable with the first and the second chamber walls in a way that the medium taken in between periods when the drive means is affecting the chamber walls controls the output of the pump by defining the receding movement of the drive ring, which movement is a function of the differential pressure force resulting from a difference in areas of engagement with the respective chamber walls on opposite sides of the drive ring. |
