Curved flexible impeller

Patent metadata

Field	Value
Publication number	US-11053937-B2
Application number	US-201716342896-A
Country	US
Kind code	B2
Filing date	Oct 5, 2017
Priority date	Nov 8, 2016
Publication date	Jul 6, 2021
Grant date	Jul 6, 2021

Abstract

An impeller is attached to a rotary shaft provided in an inner space of a housing and includes a tube fixed to the rotary shaft and a plurality of blades protruding toward an outer diameter direction from the tube. A tip of each blade is in slidable contact with an inner peripheral surface of the housing. Each blade has a shape curved toward a rotation-direction rear side of the rotary shaft in a free state and includes an extension surface on a rotation-direction front side of the rotary shaft and a compression surface on the rotation-direction rear side of the rotary shaft. A curvature radius of a root on the compression surface in the blade is formed larger than a curvature radius of a root on the extension surface in the blade.

First claim

The invention claimed is:

1. An impeller attached to a rotary shaft provided in an inner space of a housing, the impeller comprising:
a tube fixed to the rotary shaft; and
a blade protruding toward an outer diameter direction from the tube, a tip of the blade being in slidable contact with an inner peripheral surface of the housing,
wherein the blade has a shape curved toward a rotation-direction rear side of the rotary shaft in a free state and includes an extension surface on a rotation-direction front side of the rotary shaft and a compression surface on the rotation-direction rear side of the rotary shaft, and
wherein a curvature radius of a root on the compression surface in the blade is formed larger than a curvature radius of a root on the extension surface in the blade.

2. The impeller according to claim 1 ,
wherein the blade has a radial length of 9 to 15 mm,
wherein a relationship of R 11 =0.1W 1 to 0.5W 1 is satisfied with Wu representing the radial length of the blade and R 11 representing the curvature radius of a root on the extension surface in the blade,
wherein a relationship of R 13 =0.5W 1 to 1.0W 1 is satisfied with Wu representing the radial length of the blade and R 13 representing a curvature radius of a radial midsection on the compression surface in the blade,
wherein a relationship of R 14 =2W 1 to 6W 1 is satisfied with Wu representing the radial length of the blade and R 14 representing a curvature radius of a radial midsection on the extension surface in the blade,
wherein an inclination angle θ 1 of the extension surface near the tip of the blade with respect to an impeller diameter line is set to 4 to 9 degrees, and
wherein an inclination angle θ 2 of the compression surface near the tip of the blade with respect to the impeller diameter line is set to 5 to 10 degrees.

Assignees

• Nok Corp

Inventors

• Tsukamoto Koji

Classifications

• F04C5/00 Primary

  Rotary-piston machines or pumps with the working-chamber walls at least partly resiliently deformable (such pumps specially adapted for elastic fluids F04C18/00) · CPC title

• F01C5/02

  the resiliently-deformable wall being part of the inner member, e.g. of a rotary piston · CPC title

• F05C2225/02

  Rubber · CPC title

• F04C2250/20

  of the rotor · CPC title