Windmill and windmill control method

• US 6,379,115 B1
• Filed: 07/19/2000
• Issued: 04/30/2002
• Est. Priority Date: 08/02/1999
• Status: Expired due to Fees

• Current Assignee: Tetsuo Hirai
• Original Assignee: Tetsuo Hirai
• Inventors: Hirai, Tetsuo
• Primary Examiner(s): Look, Edward K.
• Assistant Examiner(s): NGUYEN, NINH H
• Application Number:
  US09/619,472
• Time in Patent Office: 650 Days
• Field of Search: 415/4.2, 415/4.4, 415/14, 415/19, 415/47, 415/48, 415/118, 416/17, 416/37, 416/40, 416/61, 416/111, 416/119, 416/155, 290/44, 290/55
• US Class Current: 416/17
• CPC Class Codes: F03D 3/068 mechanically controlled by the rotor structure
• CPC Class Codes: F03D 7/06 the wind motors having rotation axis substantially perpendicular to the air flow entering the rotor
• CPC Class Codes: F05B 2260/507 using servos, independent actuators, etc.
• CPC Class Codes: F05B 2270/32 Wind speeds
• CPC Class Codes: F05B 2270/321 Wind directions
• CPC Class Codes: Y02E 10/74 Wind turbines with rotation axis perpendicular to the wind direction

Abstract

A windmill includes a freely rotatable revolution shaft, a plurality of pairs of pivotal support rods provided at the revolution shaft, and wind receiving blades respectively and rotatably set between the pivotal support rods with wind receiving blade shafts. The windmill is applied to the driving of a lifting pump, a generator and the like by employing revolution driving force. An anemometer/anemoscope measures wind velocity and direction. A servo motor controls the direction of the wind receiving blades based on the detected velocity and direction. Various methods of control are also provided.

Claims

1. A windmill comprising:

a rotatable revolution shaft;

a plurality of pairs of upper and lower pivotal support rods provided around the revolution shaft;

wind receiving blades put between the pairs of pivotal support rods and also respectively and rotatably set between the pairs of pivotal support rods with wind receiving blade shafts;

servo motors directly coupled to said wind receiving blade shafts, for freely positioning directions of the wind receiving blades, respectively;

wind receiving blade rotating position detectors for detecting rotating positions of said wind receiving blade shafts, respectively;

revolution shaft revolving position detector for detecting revolving position of the revolution shaft;

an anemometer/anemoscope measuring a wind velocity and a wind direction; and

a servo motor control section to be input the wind direction and the wind velocity measured by the anemometer/anemoscope and to be input the revolving position of the revolution shaft and then controlling said servo motors to thereby control directions of the wind receiving blades.

2. A windmill control method in a steady state of controlling directions of wind receiving blades of a windmill consisting of a rotatable revolution shaft, a plurality of pairs of pivotal support rods provided at the revolution shaft and the wind receiving blades respectively and rotatably set between the pairs of pivotal support rods with wind receiving blade shafts, by inputting a wind direction and a wind velocity measured by an anemometer/anemoscope and a revolving position of the revolution shaft of the windmill, and thereby controlling directions of the wind receiving blades, wherein,

an upwind point on a revolution circumference on which said wind receiving blades revolve counterclockwise is set at point C, a point at 90°

clockwise from the point C on the revolution circumference is set at point A, and points at 45°

intervals from the point A are defined as points B, C and D to thereby define all points on the revolution circumference, with the final point set at a point H,

directions of the wind receiving blades are controlled so that the directions of the wind receiving blades at the point A are parallel to the wind direction, and that

while the windmill revolves once,

the wind receiving blades rotate clockwise by a {fraction (1/24)} turn at the points A to C,

the wind receiving blades rotate counterclockwise by a {fraction (1/12)} turn at the points C to G, and

the wind receiving blades rotate clockwise by a {fraction (1/24)} turn at the points G to A.

3. A windmill control method in a strong wind state of controlling directions of wind receiving blades of a windmill consisting of a rotatable revolution shaft, a plurality of pairs of pivotal support rods provided at the revolution shaft and the wind receiving blades respectively and rotatably set between the pairs of pivotal support rods with wind receiving blade shafts, by inputting a wind direction and a wind velocity measured by an anemometer/anemoscope and a revolving position of the revolution shaft of the windmill, and thereby controlling direction of the wind receiving blades, wherein

an upwind point on a revolution circumference on which said wind receiving blades revolve counterclockwise is set at a point C, a point at 90°

clockwise from the point C on the revolution circumference is set at point A, and points at 45°

intervals from the point A are defined as points B, C and D to thereby define all points on the revolution circumference, with the final point set at a point H,

directions of the wind receiving blades are controlled so that the directions of the wind receiving blades at the point A are parallel to the wind direction, and that

while the windmill revolves once,

the wind receiving blades rotate clockwise by a {fraction (5/24)} turn at the points A to C,

the wind receiving blades rotate clockwise by a {fraction (7/12)} turn at the point C to G, and

the wind receiving blades rotate clockwise by a {fraction (5/24)} turn at the points G to A.

4. A windmill control method in an emergency state such as a gale wind of controlling directions of wind receiving blades of a windmill consisting of a rotatable revolution shaft, a plurality of pairs of pivotal support rods provided at the revolution shaft and the wind receiving blades respectively and rotatably set between the pairs of pivotal support rods with wind receiving blade shafts, by inputting a wind direction and a wind velocity measured by an anemometer/anemoscope and a revolving position of the revolution shaft of the windmill, and thereby controlling directions of the wind receiving blades, wherein

a point at 90°

clockwise from an upwind point on a revolution circumference on which said wind receiving blades revolve counterclockwise is set a reference point,

the windmill is controlled so that

direction of the wind receiving blades at the reference point is parallel to the wind direction; and

the wind receiving blades rotate once clockwise while the windmill revolves once.