Small hydroelectric power generator

• US 6,768,218 B2
• Filed: 01/23/2002
• Issued: 07/27/2004
• Est. Priority Date: 02/09/2001
• Status: Expired due to Term

• Current Assignee: Sankyo Seiki Manufacturing Co., Ltd. (Nidec Corporation)
• Original Assignee: Sankyo Seiki Manufacturing Co., Ltd. (Nidec Corporation)
• Inventors: Yumita, Yukinobu
• Primary Examiner(s): Ponomarenko, Nicholas
• Assistant Examiner(s): Elkassabgi, Heba
• Application Number:
  US10/056,477
• Publication Number:
  US 20020113442A1
• Time in Patent Office: 916 Days
• Field of Search: 290/54, 290/43, 290/44, 290/53, 290/55, 322/3, 322/10
• US Class Current: 290/54
• CPC Class Codes: F03B 13/00 Adaptations of machines or engines for special use; Combinations of machines or engines with driving or driven apparatus if the apparatus aspects are predominant, see the relevant subclasses for such apparatus, e.g. H02K7/18; Power stations or aggregates incorporating only machines or engines of positive-displacement type F03C; hydraulic engineering aspects E02B; combinations with wind energy converters F03D9/008
• CPC Class Codes: F05B 2220/20 within closed fluid conduits, e.g. pipes
• CPC Class Codes: Y02E 10/20 Hydro energy

Abstract

According to the small hydroelectric power generator of the present invention, each of the outer peripheral portions of the hydraulic turbine which oppose to the ejecting openings are made in an edge shape. Therefore, the ejecting openings will not be blocked by the outer peripheral portions of the hydraulic turbine, keeping the hydraulic pressure constant. Also, since the water is constantly ejected from the ejecting openings at a plurality of locations, the hydraulic turbine rotates smoothly, reducing the rotational noise. Furthermore, the hydraulic pressure and the current are kept constant and in turn the vibration noise from the case and the current noise are reduced. Moreover, the square corners and the edges are eliminated from the back planes of the blade members to give an R-like round shape; therefore, a reverse torque is prevented from occurring to smoothen the current and in turn to reduce the noise.

Claims

1. A small hydroelectric power generator comprising:

a main case with a fluid path,

a hydraulic turbine which is arranged in said fluid pathway and turns as a predetermined flow of a fluid passes by, and

a rotator connected to said hydraulic turbine to rotate together with said hydraulic turbine, said rotator acting as a rotor portion opposed to a stator portion, so that power is generated by rotating said rotor portion relative to said stator portion as said fluid passes by;

wherein a plurality of ejecting openings are provided in said fluid pathway outside the rotational path of said hydraulic turbine for reducing an area of a flow of said fluid and for ejecting said fluid;

said hydraulic turbine has a rotational center portion and blade members which are hit by said fluid ejected from said ejecting openings, said blade members being formed such that an inner peripheral end portion is joined to said rotational center portion and outer peripheral point portions are extended toward the vicinity of said ejecting openings; and

each of said outer peripheral point portions of said blade members is formed in an edge-shape.

2. The small hydroelectric power generator as set forth in claim 1 wherein the width of said edge-shaped portion of said blade member in the circumferential direction is 30% or less of that of said ejecting opening in the rotational direction of said hydraulic turbine.

3. The small hydroelectric power generator as set forth in claim 1 wherein the plane of said blade member, the side opposite from the plane which is hit by said fluid, is curved from the inner peripheral end portion to the outer peripheral point portion with the center portion projected.

4. A hydroelectric power generator comprising:

a case having a fluid path;

a hydraulic turbine disposed in the fluid pathway and operable to turn as fluid passes;

a plurality of ejection openings provided in the fluid pathway outside the rotational path of the hydraulic turbine and operable to eject the fluid;

the hydraulic turbine including a rotational center portion and a plurality of blades that are struck by the fluid ejected from the ejection openings, each blade having an inner peripheral end portion joined to the rotational center portion and an outer peripheral portion extended toward the vicinity of the ejection openings, wherein the outer peripheral portion of each blade has an edge-shape.

5. The small hydroelectric power generator as set forth in claim 4 wherein the width of the edge-shape of the outer peripheral portion in the circumferential direction is 30% or less than the width of the ejection opening in the rotational direction of the hydraulic turbine.

6. The small hydroelectric power generator as set forth in claim 4 wherein the plane of the blade opposite from the plane that is struck by the fluid is curved from the inner peripheral end portion to the outer peripheral portion with a center portion of the blade projected.