SELF-DIRECTING WIND TURBINE

AEROGENERATEUR AUTO-ORIENTABLE

English Abstract

An improved, self directing, horizontal axis wind turbine for conversion of wind energy into useful work including generation of electricity. The said wind turbine is comprised of a plurality of two or more blades mounted on a rotor assembly rotating in a conical path about the horizontal rotor shaft downwind from the support tower. The rotation of the blades caused by the wind is transmitted to an electric generator to produce electricity. The embodiment of the said wind turbine and the electric generator along with the attachments including the generator housing are mounted on the horizontal section of a vertical shaft which is supported with bearing assemblies on the support tower. The said turbine and the vertical section of the shaft freely rotating around the support tower in response to the direction of the wind.

French Abstract

Aérogénérateur d'axe horizontal, auto-orientable, amélioré, pour convertir l'énergie du vent en travail utile comprenant la génération d'électricité. Ledit aérogénérateur comprend une pluralité de deux pales ou plus montées sur un ensemble de rotor tournant en une trajectoire conique autour de l'arbre de rotor horizontal en aval de la tour de soutien. La rotation des pales causée par le vent est transmise à un générateur électrique pour produire de l'électricité. Le mode de réalisation dudit aérogénérateur et le générateur électrique ainsi que les accessoires comprenant le logement du générateur sont montés sur une section horizontale d'un arbre vertical qui est supporté avec les ensembles de palier sur la tour de soutien. Ledit aérogénérateur et la section verticale de l'arbre tournent librement autour de la tour de soutien en réponse à la direction du vent.

Claims

Self-directing Wind Turbine
CLAIMS:
The embodiments of the invention in which an exclusive property or privilege
is claimed
are defined as follows:
1. A self-directing horizontal axis wind turbine comprising a wind turbine
assembly, an
electric generator, a frame and housing for the said generator are mounted on
a short
horizontal section of an inverted L-shaped main shaft; the said main shaft
comprising
a long vertical section and said short horizontal section, having one end
fixedly
connected to the top of the vertical section with an angle no less than 93
degrees and
no more than 100 degrees, the said vertical section of the said main shaft is
mounted
inside or alongside a vertical support tower, the said vertical section is
held securely
by means of at least two bearing assemblies allowing the said vertical section
of the
said main shaft to rotate freely in either direction as a result of the wind
force upon
the said wind turbine assembly itself without the use of any rudder mechanism
hence
self-directing.
2. The self-directing wind turbine of Claim 1 wherein the said wind turbine
assembly
further comprising a rotor assembly, a mounting plate, two or more blade arms
each
for mounting a sail-shaped blade on the said blade arm, a motion transmission
mechanism to rotate the said generator in connection with the rotation of the
said
rotor assembly; the said rotor assembly is mounted upon the said horizontal
section of
the said main shaft, the said rotor assembly and the said mounting plate and
the said
arms and the said motion transmission mechanism coupled together and as a
whole
rotating about the axis of the said horizontal section of the said main shaft.
3. The self-directing wind turbine of Claim 2 wherein a minimum of two blade
arms
mounted on the said mounting plate and having the outward end section of each
said
blade arm bent at approximately 45 degrees of slant for approximately 20
degrees in
relation to the plane of the central section of the said blade arm, such
central section
of the said blade arms being coupled to the said rotor assembly either
directly or by
means of the said mounting plate, the said rotor assembly further coupled with
the
said motion transmission mechanism.
4. The self-directing wind turbine of Claim 2 or 3 wherein sail-shaped blades
comprising a leading section, a middle section and a trailing section are
mounted on
the said blade arms in such a way that one such blade is mounted on each said
blade
arm, and the scoop of the blades are facing toward the tower making each blade
act as
a mainsail of a sailboat to capture the wind blowing in a downwind direction
relative
to the said tower.
5. The self-directing wind turbine of Claim 4 wherein the said wind turbine
assembly is
downwind in relation to the said support tower and rotates in a

Self-directing Wind Turbine
CLAIMS Continued:
predetermined circular direction while the travel path of the blades defines a
cone-shape
or conical path about the axis of the said horizontal section of the said main
shaft, while
the said self-directing wind turbine freely moves about the said vertical
section of the said
main shaft in response to the wind direction.

Description

CA 02403607 2006-04-05
SPECIFICATION:
This invention relates to horizontal axis wind turbines and in particular a
wind turbine
that is self directing in response to the wind direction without requiring a
rudder
mechanism. This wind turbine has features to simplify the design and
construction of the
blades and blades assembly, while providing improved protection against
destructive
forces of winds of high velocity.
Wind mills and wind turbines of various types have been in use for thousands
of years.
Persians were the first to use the windmills for grinding wheat and for
irrigation.
One major problem with the existing wind turbines especially with the
horizontal axis
type is the detrimental effect of high winds on these turbines- This is
especially true with
the wind turbines that utilize a rudder to direct the rotating blades into the
wind i.e. in an
up-wind direction in relation to the position of the supporting tower. The
enormous force
of high winds pushes the rotating blades assembly into the support tower and
destroys the
wind turbine. Even in down-wind type turbines with a rudder mechanism to
direct the
rotating blades assembly into the wind but downward and away from the
supporting
tower, the conflicting forces induced upon the wind turbine as a whole,
becomes
detrimental. In high winds especially in shifting winds with high velocity,
the force of the
centrifugal torque of the rotating blades assembly in one hand, and the sudden
force of
the shifting wind on the rudder act in conflict and in opposing geometry,
eventually
breaking apart the turbine.
A second problem with most wind turbines is the complexity and the high cost
associated
with the blade design and installation process. Most modern blade designs
require
complex design and manufacturing processes to layout and shape the desired
airfoils.
The complexity of such processes contributes to higher costs for building
turbine blades
and their installation on the rotor assembly-

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The present invention disclosed herein represents significant improvements to
overcome
both of these maj or problems using simple yet highly effective design
principles as
descn'bed in greatea~ details in the following disclosure of the invention and
the referenced
drawings.
Brief deacriution of the dra
Figure 1 is a side view of the present invention and shows the main components
of the
self directing and improved wind turbine. It shows the tower 1, the bearing
assemblies 2,
the main shaft 3 with a vertical section exteflding inside or along the
support tower, and a
horizontal section supporting the rotor assembly and the generator assembly.
The figure
also shows the generator housing 4, generator 5, motion transmission assembly
6, turbine
arms assembly 7, byes asseanbly 8, rotor assembly 9 and the mounting plate 10
for
mounting the arms assembly. Figure 2 is a front view of the blades 8, arms 7,
rotor
assembly 9 and the mounting assembly 10 shown as a circular plate.
Figure 3 shows the design for building a one-piece double-arm assembly. A
blade is later
mounted on each end of this arm. The angle 7-1 shows the angle for bending the
arm
plate. Figure 4 shows the one-piece double~arm assembly after being bent on
both ends,
in the same inward direction. The angle 7-2 shows the degree of the bend.
Figure 5 is the layout of the blade design. It shows the layout of two blades
each having a
section 8-1 designated to act as the mast or the leading edge of a sail,
section 8-2
designated to act as the body of the sail, and section 8-3 to act as the
trailing end of a sail.
These three areas of each blade cause each blade to act as a mainsail. The
rectangular
material (preferably aluminum sheets of no less than 1/8 inch in thickness) is
cut in half
along the solid line, and bent along the dotted lines. The black triangles are
trimmed out
to complete the two blades as indicated by the arrow 8-4 pointing to the
finished blades in
Figure 6.
Figure 7A and 7B show the design improvanent to reduce tlx destructive "push
force"
and change it more into "lift force", it also indicates how the outer tip of
the blades at the
lower edge of the "conical path" is farther away from the support tower which
again helps
prevent contact of the blades with the tower. Figure 8 is an enlarged picture
of the sail-
shaped blade design, Figure 9 demonstrates the "conical path" of the blades in
motion.
Disclosure and full deacri~lion of the best wav to build and use the
invention~
In drawings which illustrate the embodiment of the present invention, Figure 1
is a side
view of the wind turbine and related attachments mounted on top of a
supporting tower 1.
Tower I ideally has a six-sided tubular metal construct that is wider at the
base and tapers
towards the top of the tower. 'The tower is installed in a vertical position
using long and
heavy bolts and nuts to firmly attach the base plate of the tower to a strong
foundation in
the ground. Additionally the tower is secured in its vertical position by
means of high
strength cables and wires. The attachment point of these cables on the tower
is positioned
a safe distance below the top of the tower in such a way not to interfere with
the rotation
of the turbine and the blades in all directions.
2

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The main shaft 3 has a vertical section exiling downward and inside the
tubular tower
1, and secured in a vertical position by means of at least two bearing
assemblies 2. One of
the bearing assemblies is mounbod at the top of the tower, and the other one a
good
distance down and inside the tower, holding the vertical section of the main
shaft, and
allowing it to swivel and horilly in either direction.
The horizontal section of the main shaft has an angle of about 95 degrees (no
less than 93
degrees and no more than 100 degrees) relative to the vertical section of the
main shaft.
There are two advantages to this design feature. First, this angle of about 95
degrees
causes the lower part of the rotating blades to be additionally further away
from the tower
to prevent any potential contact of the blades with the tower in shifting high
winds.
Secondly, this angle of about 95 degrees helps produce a gravitational force
on the
turbine assembly to slightly offset the downwind force of the high winds that
would tend
to push the turbine assembly in a downwind direction. The horizontal section
of the main
shaft is used to hold and support ail other components of the turbine assembly
including
components 4 through 10 as shown in Figure 1.
The generator housing 4 is comprised of a frame and a cover assembled firmly
(welded)
onto the horizontal section of the shaft 3. The cover of the housing 4 is made
in such a
way to allow for ease of mounting and maintenance of an electric generator on
the said
frame, and protect the generator against natwal elements i.e. weather, rain
etc.
The said generator is further connected to a motion transmission mechanism 6.
The rotor assembly 9 is firmly ate securely attached to the end of the
horizontal section
of the main shaft 3. A large pulley together with the mounting plate 10 and
the rotor
assembly 9 are firmly sandwiched togetl~ by means of strong bolts and nuts.
This
method provides for the maintenance flexibility to replace or repair these
parts
individually. The said large pulley is then connected to a smaller pulley on
the shaft of
the electric generator through a belt. Other motion transmission alternatives
such as
gearboxes or chain and sprockets can also be used instead of pulleys and
belts.
'The mow~ting plate 10 is required for t~abines with odd number of blades e.g.
a three-
blade turbine assembly. In a two-blade or four-blade design, the arm assembly
7 is
chosen with a larger width to be easily sandwiched at the center bo the rotor
ass~ably,
eliminating the need for additional mounting plate 10. The present invention
ideally
comprises a wind turbine with three blades.
As illustrated in Figures 3 and 4, the arm assembly is bent at equal distance
from the
center of the arm assembly. In a three-blade turbine, the arm assembly in
Figure 3 is cut
at the center to prod~e two disjoint arms. A third arm is built in a similar
way. The three
arms are then mounted on a mounting plate 10 shown in Figures 1 and 2.
In a two-blade or four-blade turbine, the arm assembly shown in Figure 3
remains one
piece, bent on both ends as shown. The arms assembly is bent at about 45
degrees
indicated by angles 7-1. The amount of bend 7-3 in Figure 4 is about 20
degrees.
This twist in the arms assembly provides for the required inclination for the
end of
the acme 7, outward and away ffro~ the rotor ably 9 as shows in Figure 1.
Consequently the blades are positioned to rotate in a conical path downwind
and

CA 02403607 2006-04-05
away from the tower 1 as shown in Figure 1. The amount of the bend indicated
by
the angle 7-2 in Figure 4 also defines the pitch of the blades i.e.
approximately 20
degrees in relation to the direction of the wind. This is a simple yet highly
effective
feature of the disclosed invention.
As demonstrated in Figures 5 and 6, section 8-l of each blade is bent along
the dotted
line for about 30 degrees. Section 8-3 is bent approximately 20 degrees along
the dotted
line. Each blade therefor has a scoop shape similar to the mainsail of a
sailboat.
The blades 8 and anus 7 are then mounted and coupled with the rotor assembly 9
and the
mounting plate 10 (optional for turbines with even number of blades as
described earlier)
as shown in Figure 2. Once assembled, the inside scoop of the blades will face
the tower
1 as shown in Figure l to catch the wind and start rotating. Properly
assembled blades
will rotate in a direction such that section 8-1 of Figure 5 is the leading
edge of the blade
while section 8-3 of Figure S acts as the trailing edge of the blade.
The center of gravity of the turbine assembly comprising of components 4
through 10 as
shown in Figure 1 is outside and away from the axis of the vertical section of
the main
shaft 3. This makes it possible for the complete turbine assembly including
the vertical
section of the main shaft 3 to swivel about the vertical section of the main
shaft 3 in
either direction in response to the wind direction, hence a self-directing
wind turbine.
9~

Representative Drawing