Abstract: An example impeller includes: an impeller body in which an internal channel is formed, the internal channel extending inside the impeller body in a direction of a rotation axis spirally about the rotation axis to connect an inlet and an outlet; and at least one centrifugal vane provided in the impeller body. The internal channel including the inlet and the outlet has a predetermined passage diameter. An external channel is formed so as to continue to the outlet and go around the circumferential surface of the impeller body, the external channel being defined by the centrifugal vane and being recessed inward in the radial direction from the circumferential surface of the impeller body. At least a part in a flow direction of the external channel has a channel width in the direction of the rotation axis smaller than the width of the outlet.

Abstract: An impeller includes an impeller body which rotates about a rotation axis, and a vane which is provided at the impeller body. The impeller body receives force asymmetric with respect to the rotation axis in driving and rotation in a fluid in a manner that radially inward fluid force, which is generated due to arrangement of the vane, acts on a predetermined point in a peripheral direction. In the impeller body, a filled space filled, in a fluid, with the fluid is formed.

Abstract: An impeller includes an impeller body in which an internal flow path and a recessed section are formed; a lid covering an opening of the recessed section; and a balance weight arranged between the impeller body and the lid. The lid is attached and fixed to the impeller body through an engagement section. Holding sections for the balance weight are formed in a back-side surface of the lid. When attaching and fixing the lid to the impeller body, the balance weight is sandwiched between the holding section of the lid and the impeller body to be fixed.

Abstract: An impeller include a substantially cylindrical impeller body with an internal flow path connecting between an inlet opening through a first end surface and an outlet opening through a circumferential surface; and a balance weight embedded in the impeller body. The balance weight has a vertically-elongated shape in which its height in a cylindrical axis direction is larger than its thickness in a radial direction. The vertically-elongated balance weight is embedded in a circumferential section of the cylindrical impeller body.

Abstract: An impeller includes an impeller body which rotates about a rotation axis, and a vane which is provided at the impeller body. The impeller body receives force asymmetric with respect to the rotation axis in driving and rotation in a fluid in a manner that radially inward fluid force, which is generated due to arrangement of the vane, acts on a predetermined point in a peripheral direction. In the impeller body, a filled space filled, in a fluid, with the fluid is formed.

Abstract: An example impeller includes: an impeller body in which an internal channel is formed, the internal channel extending inside the impeller body in a direction of a rotation axis spirally about the rotation axis to connect an inlet and an outlet; and at least one centrifugal vane provided in the impeller body. The internal channel including the inlet and the outlet has a predetermined passage diameter. An external channel is formed so as to continue to the outlet and go around the circumferential surface of the impeller body, the external channel being defined by the centrifugal vane and being recessed inward in the radial direction from the circumferential surface of the impeller body. At least a part in a flow direction of the external channel has a channel width in the direction of the rotation axis smaller than the width of the outlet.