| 主权项 |
1. A suction device, comprising:
an outer tube having an outer inlet at a first outer end; a proximal opening at a proximal end of the outer tube to receive an inner suction tube, wherein the proximal opening is smaller in diameter than the outer tube; and a wall with an inner surface and an outer surface; an inner suction tube to be located within the outer tube, the inner suction tube having an inner inlet at a first inner end corresponding to the first outer end of the outer tube, an inner outlet at a proximal end of the inner suction tube, and a wall with an inner surface and an outer surface, wherein one or more holes through the wall of the inner suction tube are located only near the inner inlet at the first inner end and nowhere else along the wall of the inner suction tube; wherein the inner inlet of the inner suction tube, when the device is fully assembled, is offset by a distance from the outer inlet of the outer tube such that the inner inlet of the inner suction tube is recessed within the outer tube; wherein when a suction pressure is applied to the inner outlet at the proximal end of the inner suction tube and the first outer end of the outer tube contacts a fluid, a first vacuum is formed in a space directly between a proximal portion of the outer surface of the wall of the inner suction tube and a proximal portion of the inner surface of the wall of the outer tube, and a second vacuum is formed within the inner suction tube. |
