Patent ID: 8550788

Claim:
An impeller device comprising: a magnetic detecting element for detecting a rotational position of a rotary impeller; a magnet which is paired with the magnetic detecting element for detecting the rotational position of the rotary impeller; and an impeller shaft for rotatably supporting the rotary impeller; wherein the rotary impeller is rotatably supported in an inside of a fluid space formed in a case body; wherein the case body includes a case main body which is formed with the fluid space and a cover body which is attached to the case main body for sealing the fluid space; wherein the magnetic detecting element is held by the cover body; wherein the rotary impeller is formed with a bottomed recessed part which is recessed toward a side of the magnetic detecting element so as to have an opening through which the magnet is inserted from an opposite side to the magnetic detecting element, and the opening of the recessed part is sealed with resin injected by insert molding so that the magnet is buried and sealed in the bottomed recessed part of the rotary impeller; wherein the impeller shaft is supported by the case main body and the cover body; wherein the rotary impeller is formed with blade parts on an outer wall in a radial direction of the rotary impeller and the outer wall is extended to a cover body side with respect to the blade parts; and wherein the cover body is provided with a circular ring shaped recessed part around the impeller shaft so that the outer wall and the bottomed recessed part of the rotary impeller are disposed in the circular ring shaped recessed part and, so that the magnet buried in the bottomed recessed part of the rotary impeller is disposed in the circular ring shaped recessed part of the cover body.