Patent ID: 8292269

Claim:
A microscopic bubble generating apparatus which blows microscopic bubbles into water in a septic tank or river thereby to clean the water, the apparatus comprising: a Roots-type pump including a pump casing provided with a suction port and a discharge port, a pair of multi-lobed Roots rotors housed in the pump casing, and a drive motor which rotates the rotors; a suction pipe connected to the suction port of the pump casing; a discharge pipe connected to the discharge port of the pump casing; and a conduit which communicates with the suction pipe and is provided with an air inlet and a collision member with which sucked water is caused to collide, wherein the Roots-type pump is operated to suck water through the suction pipe and to cause the water mixed with air sucked through the air inlet to collide with the collision member so that a number of bubbles are generated; the bubbles are refined by a compressing action of the Roots-type pump thereby to be rendered microscopic; and the water containing the microscopic bubbles is released from the discharge pipe into the water in the septic tank or the river.