Patent 5263897 Issued on November 23, 1993. Estimated Expiration Date: April 30, 2012. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
A fluid suction nozzle and a fluid-treating apparatus are used in the cleaning of air inside a local space. The suction nozzle has a suction passage and plural annular discharge passages surrounding the suction passage. The nozzle is connected with an air cleaner, etc. The air inside a local space is to be drawn in through the suction passage. At the same time, a larger amount of air is to be discharged from the discharge passages. The velocity at which fluid will flow from the outer discharge passage is smaller than that at which fluid from the same source will flow from the inner discharge passage.