To provide a drain pump for drain generated from an air conditioner and the like capable of further lowering noises during the pump operation in comparison with a conventional technology.
This drain pump is provided with a bellmouthed-shape housing 2 above a cylinder part 4 having an inflow port 5 in the lower end part. In a runner 10, a runner boss 17 fitted around a driving shaft 21, a disc type runner disc 11, three triangular rotational blades 13 on a direct plane on the vertical axis extension of the runner boss, and a small-diameter blade 13 inserted inside a cylinder part 4 below the rotary blades are integrally formed, and the runner 10 is arranged freely rotationally inside the housing at a clearance so that the small-diameter blade is faced to the inflow port while the runner disc is housed on the large diameter side of the bellmouthed shape. The rotational blades 12 and the small-diameter blade 13 in the runner form a radial arm part 14 from the base part on the axial center side to the outer circumference 15, and the arm part holds the runner disc 11 having a communication port 18 opening on the upper centrifugal face 16 in the vicinity of the circumferential edge of the runner boss from the base part.
TOYODA AKIRA
CHIBA YASUTSUNE
TANABE KAZUICHI
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