To provide a small size volute pump of a small leakage of fluid inside the volute pump and of high pump efficiency.

This volute pump 10 has a disk shape blade part 24 including a plurality of blades 21 on an outer circumference, an impeller 20 provided with a cylindrical bearing part 25 including a bearing on an inner circumference, a shaft 40 supporting the impeller 20 movably in a thrust direction, and a drive device 50 arranged around the bearing part 25 included in the impeller 20 and driving and rotating the impeller 20 stored in a case member 1. The case member 1 is provided with a fluid moving part 2 storing the blade part 24 and a drive device storage part 3 storing the drive device 50. Dynamic pressure roves 22a, 22b generating dynamic pressure based on rotation of the impeller 20 are formed at positions corresponding to an inside of the blade 21 on surfaces 6a, 6b of the case member 1 opposing to both surfaces 7a, 7b of the impeller 20 or the both surfaces of the impeller.

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