ADJUSTABLE FLYWHEEL

ROUE REGLABLE

English Abstract

An adjustable flywheel for a windmill includes a body having a central hub. Means are provided for connecting the central hub to a rotating shaft. The positioning of the rotating shaft in the central hub defines a symmetrical rotational axis for the body and the body provides inertial mass to the rotating shaft. The body has a plurality of arms which extend radially outwardly from the central hub. Each of the arms has two or more weight anchoring positions. The inertial capacity of the flywheel is adjustable by securing weights to each of the arms in selected of the weight anchoring positions.

French Abstract

Une roue réglable pour une éolienne comprend un corps comportant un moyeu central. Des mécanismes sont fournis pour relier le moyeu central à un arbre rotatif. Le positionnement de larbre rotatif dans le moyeu central définit un axe de rotation symétrique pour le corps et le corps fournit une masse inertielle à la tige rotative. Le corps comporte une pluralité de bras qui sétendent radialement vers lextérieur à partir du moyeu central. Chacun des bras comporte au moins deux positions dancrage de poids. La capacité inertielle de la roue peut être réglée en fixant des poids à chacun des bras dans une sélection de position dancrage de poids.

Claims

7
What is Claimed is:
1. In combination, an adjustable flywheel and a windmill, the adjustable
flywheel comprising:
a flywheel body having a central hub;
means for connecting the central hub to a rotating shaft, the positioning of
the rotating
shaft in the central hub defining a symmetrical rotational axis for the
flywheel body and the
flywheel body providing inertial mass to the rotating shaft
the flywheel body comprising:
a plurality of arms that extend radially outwardly from the central hub, each
of
the arms having two or more weight anchoring positions, the inertial capacity
of the flywheel
being adjustable by securing weights to each of the arms in selected of the
weight anchoring
positions; and
the windmill comprising a rotating shaft, the flywheel being secured to the
rotating
shaft of the windmill.
2. The combination of Claim 1, wherein a blade support body is provided
having
an outer circumference to which a plurality of fixed rotor blades are secured
to the shaft, such
that wind striking the rotor blades imparts a rotational force to the blade
support body and
causes the shaft to rotate.
3. The combination of Claim 1, wherein the windmill has a fixed open frame
support structure with four sides.
4. The combination of Claim 1, wherein the shaft is supported in a vertical
orientation.
5. The combination of Claim 3, wherein wind deflectors project outwardly
from
only one corner on each of the sides of the open frame support structure to
capture and deflect
wind onto a selected face of each of the rotor blades.

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6. The combination of Claim 2, wherein the rotor blades are elongated with
a
concave face and a convex face.
7. The combination of Claim 6, wherein concave face of each of the rotor
blades
has a top end, a bottom end, and wind retaining dividers are positioned on the
concave face
between the top end and the bottom end.
8. The combination of Claim 2, wherein each of the rotor blades has an
inside
edge and an outside edge, with a brace extending from the outside edge of one
rotor blade to
the inside edge of a following rotor blade.
9. The combination of Claim 3, wherein the frame structure is modular and
can
be vertically stacked to increase capacity, with a linkage connecting the
shafts of the frame
structures which are stacked so that the shafts rotate together.
10. The combination of Claim 9, wherein a lowermost frame structure rests
upon
a base which elevates the frame structure.
11. The combination of Claim 1, wherein the weights are secured to the arms
such
that the inertial mass of the flywheel body is distributed evenly about the
hub.
12. A method of adjusting the inertial capacity of a flywheel attached to a
windmill, the method comprising:
attaching the flywheel to a rotating shaft of the windmill, the flywheel
comprising:
a flywheel body comprising a central hub and a plurality of arms that extend
radially outwardly from the central hub, each of the arms having two or more
weight
anchoring positions, the flywheel having a first inertial capacity when the
weights are secured
to each of the arms in first weight anchoring positions; and
means for connecting the central hub to the rotating shaft, the positioning of
the rotating shaft in the central hub defining a symmetrical rotational axis
for the flywheel
body and the flywheel body providing inertial mass to the rotating shaft; and

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adjusting the inertial capacity of the flywheel in response to a change in
wind
conditions, wherein the weights are moved from a first weight anchoring
position to a second
weight anchoring position.
13. The method of Claim 12, further comprising providing a blade support
body
having an outer circumference to which a plurality of fixed rotor blades are
secured to the
shaft, such that wind striking the rotor blades imparts a rotational force to
the blade support
body and causes the shaft to rotate.
14. The method of Claim 12, wherein the windmill has a fixed open frame
support
structure with four sides.
15. The combination of Claim 12, wherein the shaft is supported in a vertical
orientation.
16. The combination of Claim 14, wherein wind deflectors project outwardly
from
only one corner on each of the sides of the open frame support structure to
capture and deflect
wind onto a selected face of each of the rotor blades.
17. The combination of Claim 13, wherein the rotor blades are elongated
with a
concave face and a convex face.
18. The combination of Claim 17, wherein concave face of each of the rotor
blades has a top end, a bottom end, and wind retaining dividers are positioned
on the concave
face between the top end and the bottom end.
19. The combination of Claim 13, wherein each of the rotor blades has an
inside
edge and an outside edge, with a brace extending from the outside edge of one
rotor blade to
the inside edge of a following rotor blade.

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20. The combination of Claim 14, wherein the frame structure is modular and
can
be vertically stacked to increase capacity, with a linkage connecting the
shafts of the frame
structures which are stacked so that the shafts rotate together.
21. The combination of Claim 20, wherein a lowermost frame structure rests
upon
a base which elevates the frame structure.
22. The combination of Claim 12, wherein the weights are secured to each of
the
arms such that the weight is distributed evenly about the hub.

Description

CA 02746564 2011-07-12
TITLE
[0001] Adjustable Flywheel
FIELD
[0002] There is described an adjustable flywheel that was developed for use in
a vertical
axis windmill.
BACKGROUND
[0003] Most electric generators and mechanical components, which are driven by
windmills, have an optimum operating range. If wind conditions were always
consistent, it
would be a simple matter of sizing components so that the windmill always
operated within
that optimum operating range. Unfortunately, wind acting upon a windmill is
often subject to
variations in intensity from day to day. Even from hour to hour and from
moment to moment,
the wind may experience periods of gusting and periods of relative calm. For
this reason,
most windmills are equipped with a flywheel, which tends to keep the rotation
relatively
consistent. What is required is a flywheel that can be adjusted to suit
prevailing wind
conditions. The present invention was developed for use in a vertical axis
windmill. United
States Patent 7,866,938 (Kariya) is an example of a relatively recent patent
relating to a
vertical axis windmill.
SUMMARY
[0004] There is provided an adjustable flywheel which includes a flywheel body
having
a central hub. Means are provided for connecting the central hub to a rotating
shaft. The
positioning of the rotating shaft in the central hub defines a symmetrical
rotational axis for the
body and the body provides inertial mass to the rotating shaft. The body has a
plurality of
arms which extend radially outwardly from the central hub. Each of the arms
has two or more
weight anchoring positions. The inertial capacity of the flywheel is
adjustable by securing
weights to each of the arms in selected of the weight anchoring positions.
[0005] The adjustable flywheel, as described above, was initially developed
for use in a
windmill. It is now appreciated that it may have uses in any other application
that requires an
inertial mass. With the adjustable flywheel, as described above, the inertial
capacity of the
flywheel is adjusted by either moving the weights inward toward the central
hub or outward

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away from the central hub. The farther away from the central hub that the
weights are
positioned, the greater is the inertial capacity of the flywheel.
[0006] When adapting the flywheel for use with a windmill, the flywheel body
is attached
to a windmill shaft. A blade support body is secured to the windmill shaft.
Blade support
body has an outer circumference to which a plurality of fixed rotor blades are
secured. Wind
striking the rotor blades imparts a rotational force via the blade support
body to the shaft.
[0007] While the structure of the windmill is not directly relevant to the
adjustable
flywheel, the flywheel was developed with a particular style of windmill and
is known to
work well in that structure. It is preferred that the support structure is an
open frame structure
with four sides. It is preferred that the windmill is a vertical axis
windmill, with the shaft
supported in a vertical orientation with the rotor blades extending radially
outwardly from the
shaft in a vertical orientation.
[0008] Although beneficial results may be obtained through the use of the
windmill
described above, even more beneficial results may be obtained through the
addition of wind
deflectors to deflect wind onto the rotor blades. It is preferred that the
wind deflectors project
outwardly from only one corner on each of the sides of the open frame
structure to capture
and deflect wind across the side of the open face structure and onto a
selected face of each of
the rotor blades. It is undesirable for the wind to be acting equally on
returning rotor blades,
as this reduces efficiency. By selectively deflecting the wind in this manner,
a greater
rotational force is exerted on one face to promote the desired rotation.
[0009] Although beneficial results may be obtained through the use of the
windmill
described above, even more beneficial results may be obtained by selected
improvements to
the rotor blades. It is preferred that the rotor blades are elongated with a
concave face and a
convex face. The concave face captures the wind and the convex face tends to
merely divert
the wind around. The concave face of each of the rotor blades has a top end
and a bottom end.
It is preferred that wind retaining dividers be positioned on the concave face
between the top
end and the bottom end. These dividers improve the capture of wind and result
in a greater
rotational force, when compared to identical rotor blades without dividers.

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[0010] A significant torsional force is exerted upon the rotor blades,
especially when
wind deflectors are used. Even more beneficial results may be obtained by
reinforcing the
rotor blades. Each of the rotor blades has an inside edge and an outside edge.
It is preferred
that a brace be placed from the outside edge of one rotor blade to the inside
edge of a
following rotor blade.
[0011) There are always issues of capacity. It is preferred that the frame
structure be
arranged as modules that can be vertically stacked to increase capacity. A
linkage is then
used to connect the shafts of the frame structures, which are stacked.
[0012] There are a number of safety concerns when windmills are operating. It
is
preferred that a lowermost frame structure rests upon a base, which elevates
the frame
structure. This raises the operating windmill high enough that a member of the
public who
wanders in the area will not be harmed. It also allows for storage space to be
provided below
the windmill.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] These and other features will become more apparent from the following
description in which reference is made to the appended drawings, the drawings
are for the
purpose of illustration only and are not intended to be in any way limiting,
wherein:
FIG. 1 is a top plan view of a windmill with an adjustable flywheel.
FIG. 2 is a side elevation view of the windmill shown in FIG. 1.
FIG. 3 is a top plan view of the adjustable flywheel used in the windmill
shown in
FIG.1.
FIG. 4 is a perspective view of the rotor blade used in the windmill shown in
FIG.1.
DETAILED DESCRIPTION
[0014] An adjustable flywheel generally identified by reference numeral 10,
will now be
described with reference to FIG. 1 through 4. Adjustable flywheel 10 is shown
incorporated

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4
into the construction of a windmill 100.
Structure and Relationship of Parts:
[0015] Referring to FIG. 1, windmill 100 has an open frame support structure
12 with
four sides 15. It should be understood that windmill 100 may be constructed
with a different
number of sides and a closed frame. Shaft 16 is supported for rotation by
support structure
12 in a vertical orientation.
[0016] Referring to FIG. 3, flywheel 10 has a flywheel body 18 with a central
hub 20.
Central hub 20 is secured to shaft 16 by welding, fasteners or other means.
The positioning of
shaft 16 in central hub 20 serves to define a symmetrical rotational axis for
body 18 and body
18 provides inertial mass during rotation of shaft 16. Body 18 has a plurality
of arms 22
which extend radially outwardly from central hub 20 with each arm 22 having
two or more
weight anchoring positions 24. The inertial capacity of flywheel 18 is
adjustable by securing
weights 26 using screws, pins or other securing devices in one of the weight
anchoring
positions 24. The farther away from the central hub that the weights are
positioned, the
greater is the inertial capacity of the flywheel.
[0017] Referring to FIG. 3, in the windmill application, a blade support body
13 is
provided that has an outer circumference to which are secured a plurality of
fixed rotor blades
14. Body 13 is and secured to shaft 16, such that wind striking rotor blades
14 imparts a
rotational force to blade support body 13 causing shaft 16 to rotate.
Referring to FIG. 4,
rotor blades 14 are elongated with a concave face 30 and a convex face 32.
Concave face 30
of each rotor blade 14 has a top end 34, a bottom end 36 and a wind retaining
divider 38
positioned between top end 34 and bottom end 36. It has been found that wind
retaining
divider 38 improves the ability of concave face 30 to capture wind. Referring
to FIG. 1, rotor
blades have an inside edge 40 and an outside edge 42 with a brace 44 extending
from outside
edge 42 of one rotor blade 14 to inside edge 40 of a following rotor blade 14.
Brace 44
strengthens body 13 to prevent torsional load created by wind gusts from
breaking off one of
rotor blades 14.

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[0018] Referring to FIG. 1, wind deflectors 28 project outwardly from one
corner 29 on
each of the sides of open frame structure 12 to capture and deflect wind
across side of open
face structure 12 and onto a selected face, ie concave face 30, of each of
rotor blades 14.
5 [0019] Referring to FIG. 2, support structure 12 may be modular, allowing a
plurality of
windmills 100 each with their own flywheel 10 to be vertically stacked to
increase capacity. A
linkage 46 connects shafts 16 of each windmill 100, so that shafts 16 rotate
together. The
lowermost frame structure 12 rests upon a base 48 which elevates frame
structure 12.
[0020] Referring to FIG. 2, a recommended safety feature is the addition of a
shaft brake,
shown as box 50. It is preferred that one be placed at a top and at a bottom
of a shaft
structure. Shaft brakes 50 are commercially available; the one for the proto-
type was
purchased from DEXTER AXLE (Trademark). It is also preferred that a locking
pin 52 be
provided. Locking pin 52 is extended through aligned openings in one of
flywheel body 18 or
blade support body 13 of flywheel 10 and support frame 12. Locking pin 52
extends through
flywheel body 18 or blade support body 13 into support frame 12 stops rotation
of flywheel
10.
Operation:
[0021] Referring to FIG. 1, regardless of the direction of the prevailing
wind, wind is
deflected by wind deflectors 28 on support structure 12 onto concave face 30
of rotor blades
14. Wind retaining divider 38 improves the ability of concave face 30 to
capture wind. When
the wind speed exceeds a threshold value, there is sufficient wind captured to
set blade
support body 13 of flywheel 10 in motion and cause rotation of shaft 16. If
the wind is
insufficient to set blade support body 13 in motion and rotate shaft 16, the
inertial mass
represented by flywheel 10, shown in FIG. 3, can be adjusted, by altering the
positioning of
weights with respect to weight anchoring positions 24 on arms 22. Referring to
FIG. 3, once
shaft 16 is in motion, it will tend to remain in motion due to the inertia
provided by flywheel
10, as long as there are periodic gusts to maintain flywheel 10 in motion.
Referring to FIG. 1,
as the wind increases in intensity, brace 44 extending from outside edge 42 of
one rotor blade
14 to inside edge 40 of a following rotor blade 14 prevents the strength of
the wind from

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breaking off one of rotor blades 14. Should the strength of the wind be viewed
as rendering
operation unsafe, shaft brake 50 may be applied to bring shaft 16 to a stop,
which in turn
retards motion of flywheel 10 and blade support body 13 and then locking pin
52 inserted to
lock body 18 to support structure 12.
[0022] In this patent document, the word "comprising" is used in its non-
limiting sense to
mean that items following the word are included, but items not specifically
mentioned are not
excluded. A reference to an element by the indefinite article "a" does not
exclude the
possibility that more than one of the element is present, unless the context
clearly requires that
there be one and only one of the elements.
[0023] The scope of the claims should not be limited by the preferred
embodiments set
forth as examples, but should be given the broadest interpretation consistent
with the
description as a whole.

Representative Drawing