Ex Parte Dahl et al

Patent Trials and Appeals Board

May 21, 2019

14111039 - (D) (P.T.A.B. May. 21, 2019)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
14/111,039 10/10/2013
20529 7590 05/23/2019
NATH, GOLDBERG & MEYER
Joshua Goldberg
112 South West Street
Alexandria, VA 22314
FIRST NAMED INVENTOR
Martin Dahl
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www .uspto.gov
ATTORNEY DOCKET NO. CONFIRMATION NO.
32904U 7398
EXAMINER
LEGENDRE, CHRISTOPHER RY AN
ART UNIT PAPER NUMBER
3745
NOTIFICATION DATE DELIVERY MODE
05/23/2019 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
USPTO@nathlaw.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte MARTIN DAHL, BJARNE KRAB MORTENSEN,
and BENJAMIN HORNBLOW
Appeal2018-007193
Application 14/111,039
Technology Center 3700
Before EDWARD A. BROWN, WILLIAM A. CAPP, and LISA M. GUIJT,
Administrative Patent Judges.
CAPP, Administrative Patent Judge.
DECISION ON APPEAL
STATEMENT OF THE CASE
Appellants1 seek our review under 35 U.S.C. § 134(a) of the final
rejection of claims 1 and 3-16. We have jurisdiction under 35 U.S.C. § 6(b).
We REVERSE.
1 LM WP Patent Holding A/Sis the real-party-in-interest. Appeal Br. 3.
Appeal2018-007193
Application 14/111,039
THE INVENTION
Appellants' invention relates to wind turbines. Spec. 1. Claim 1,
reproduced below, with paragraph indentation added, is illustrative of the
subject matter on appeal.
1. A wind turbine blade (2) for a rotor having a
substantially horizontal rotor shaft, the rotor comprising a
hub (23) from which the wind turbine blade (2) extends
substantially in a radial direction when mounted to the hub (23),
the wind turbine blade (2) having a longitudinal direction
extending from a root region (26) to a blade region, the
root (26) and the blade region, respectively, being closest to and
furthest away from the hub (23) when the wind turbine blade
(2) is mounted to the hub, the root region (26) having a
substantially circular profile,
the wind turbine blade (2) being formed of a fibre-
reinforced polymer material comprising a polymer matrix and a
first and a second reinforcement fibre material being embedded
in the polymer matrix,
the wind turbine blade further comprising
a first region, a second region and a transition region
between the first and the second region, the first region,
the second region and the transition region extending in the
longitudinal direction,
the first region being predominantly reinforced with the first
reinforcement fibre material,
the second region being predominantly reinforced with the
second reinforcement fibre material,
the first and the second reinforcement fibre material being
different from each other having different E-modulus and
material properties,
the transition region having a gradually changing
distribution of the first and the second reinforcement fibre
material in the longitudinal direction, characterised in that the
first region extends in the root region (26) and in that the first
reinforcement fibre material is a metal,
wherein the first region extends fully in the root region (26).
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Application 14/111,039
THE REJECTIONS
The Examiner relies upon the following as evidence in support of the
rejections:
Grabau
Eyb
Bech
Grabau '225
Sorensen
US 7,364,407 B2
US 7,438,533 B2
US 7,521,105 B2
WO 2010/018225 A2
US 2010/0290912 Al
Apr. 29, 2008
Oct. 21, 2008
Apr. 21, 2009
Feb. 18,2010
Nov. 18, 2010
http://www. clearwatercomposites. com/resources/Properties-of-
carbon-fiber, Properties of Carbon Fiber, (hereinafter
"Clearwater"), accessed May 12, 2016.
The following rejections are before us for review:
1. Claims 1, 3-8, 10, 11, and 14-16 are rejected under 35 U.S.C.
§ 103 as being unpatentable over Sorensen, Grabau, Grabau '225, Eyb, and
Clearwater.
2. Claim 9 is rejected under 35 U.S.C. § 103 as being unpatentable
over Sorensen, Grabau, Grabau '225, and Eyb.
3. Claims 12 and 13 are rejected under 35 U.S.C. § 103 as being
unpatentable over Sorensen, Grabau, Grabau '225, and Bech.
Claim 1
OPINION
Unpatentability of Claims 1, 3-8, 10, 11, and 14-16
over Sorensen, Grabau, Grabau '225, Eyb, and Clearwater
The Examiner finds that Sorensen discloses the invention substantially
as claimed except for the details of the material composition of the blade
shell, for which the Examiner relies on Grabau, Grabau '225, Eyb, and
Clearwater. Final Action 4-7. According to the Examiner, Grabau discloses
wind turbine blades formed of fiber reinforced polymer materials that
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Application 14/111,039
include longitudinal transition regions comprising varying quantitative ratios
of fiber types. Id. at 5. The Examiner relies on Grabau '225 as
incorporating steel fibers in the root section of a wind turbine blade. Id. The
Examiner relies on Eyb as disclosing that it was known that rotor loads are
concentrated at the blade root portion of a wind turbine. Id. at 6. The
Examiner concludes that it would have been obvious to a person of ordinary
skill in the art at the time the invention was made to form a turbine blade
with longitudinal transition sections and use steel fibers in the root section.
Id. at 5-6. According to the Examiner, a person of ordinary skill in the art
would have done this to reduce cost, reduce weight, reduce dead load
moment, and increase stiffness to prevent excessive blade tip deflection. Id.
Appellants argue that Grabau's teaching relates to properties of the
blade tip, not the blade root. Appeal Br. 10-11. Appellants argue that
Grabau's blade root is made of carbon fibers and that the dimensions of the
blade root are based on the use of carbon fibers. Id. at 11. Appellants
acknowledge that Grabau '225 discloses the general concept of reinforcing
wind turbine blades with metallic fibers, however, Appellants contend that
Grabau '225 does not suggest varying the fiber composition in the
longitudinal direction of the blade. Id. at 12. "Grabau '225 does not
mention the quantitative ratio between two fiber types should be varied in
the longitudinal direction. Further, Grabau '225 does not suggest a second
longitudinal part of the blade should be predominantly reinforced by a
second type of fiber." Id. Appellants argue that Eyb merely teaches the
general principle that rotor loads are concentrated at the blade root and that
Clearwater merely teaches material properties of steel and carbon fibers. Id.
at 12-13. Finally, Appellants argue that, given the fact that Sorensen is
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Application 14/111,039
directed to a hub assembly, Grabau is directed to a blade tip, and Grabau
'225 is directed to a longitudinally extending reinforcement section of a
blade, a person of ordinary skill in the art would not have been motivated to
combine the references to achieve the claimed invention. Id. at 12.
In response, the Examiner points out that Grabau '225, not Grabau, is
relied on as teaching metallic reinforcing fibers. Ans. 3. The Examiner
further states that the teaching of Grabau relates to the entire blade and not
just the blade tip. Id. at 4. The Examiner further states that the rejection
does not rely on Grabau '225 as disclosing a second longitudinal part of the
blade should be predominantly reinforced by a second type fiber as such
feature is supplied by Grabau in the combination. Id. at 9.
Specifically in response to Appellants' argument that there is no
motivation to combine the references, the Examiner states that:
(1) Sorenson discloses details of a wind turbine blade root required for a
blade-hub mounting arrangement; (2) Grabau discloses the advantages of
multiple fiber types along the length of a blade and that a transition region
between fiber types can occur along almost the entirety of the blade; and (3)
Grabau '225 discloses the use of steel fibers in a wind turbine blade root
section. Id. at 10. The Examiner finds that the combined teachings of
Grabau, Grabau '225, and Eyb indicate that blade root reinforcement is
advantageous by permitting reduction in cross-sectional size of the blade
root and hub mounting flanges. Id. The Examiner concludes that there is
sufficient overlap in the subject matter taught by the references and that
there is rational underpinning for the proposed combination. Id.
Sorenson is directed to improvements in wind turbine blade root and
hub assemblies. Sorenson ,i,i 5-10. Grabau discloses a wind turbine blade
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Application 14/111,039
of fiber reinforced polymer. Grabau, col. 2, 63-64. In Grabau, two types of
fibers are distributed in the polymer matrix such that the quantitative ratio of
the two types of fibers varies gradually and continuously in the longitudinal
direction of the blade. Id. at col. 3, 11. 4-10. In Grabau, the first type of
fibers are glass fibers, the second type are carbon fibers, and the amount of
carbon fibers increases toward the tip of the blade, resulting in weight
reduction in the outermost part of the blade. Id. at col. 3, 11. 15-23. The
length of the zone including the blade tip may constitute up to 90 percent of
the blade's entire length. Id. at col. 4, 16-20. Grabau '225 is directed to a
wind turbine blade with a shell structure made of fiber reinforced polymer
material including a polymer matrix and fiber reinforcement material
embedded in the polymer matrix. Grabau '225 p. 4, 11. 3-24. In
Grabau '225, at least 20 percent of the volume of the fiber reinforcement
material consists of metallic wires. Id. at p. 4, 23-24.
A person of ordinary skill in the art understands that a wind turbine
comprises a plurality of blades that rotate about a hub. Most of the length of
the blade is shaped as an airfoil. A blade root is disposed between the airfoil
and the hub and facilitates mechanical attachment of the blade to the hub.
Appellants' invention includes a root region that incorporates a first
reinforcement fiber of metal. Spec. 2, 11. 3 5-3 6. In Appellants' blade, a first
region, which extends into the root, is predominantly reinforced with metal
fiber and a second region is predominantly reinforced with a second fiber.
Spec. p. 1, 1. 5 - p. 2, 1. 19.
No single prior art reference cited in the rejection explicitly teaches
fabricating a blade root that is predominantly reinforced with a metal fiber.
Thus, the issue before us is whether the combined teachings of the prior art
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suggest fabricating a blade root that is predominantly reinforced with metal
fiber. We conclude that they do not.
An invention is not obvious where vague prior art does not guide an
inventor toward a particular solution. See Bayer Schering Pharma AG v.
Barr Labs., Inc., 575 F.3d 1341 1347 (Fed. Cir. 2009). Similarly, a finding
of obviousness does not obtain where the prior art gives only general
guidance as to the particular form of the claimed invention or how to achieve
it. See In re O'Farrell, 853 F.2d 894, 903 (Fed. Cir. 1988). This expresses
essentially the same idea as the requirement that an identified solution, to be
obvious, needs to be "predictable." KSR Int 'l Co. v. Teleflex Inc., 550 U.S.
398, 421 (2007).
Here, the prior art, at best, gives general guidance that metal fibers
may be useful in reinforcing the airfoil portion of a wind turbine blade
(Grabau '225). The prior art also gives general guidance that it may be
advantageous to transition from one ratio of two types of fibers to another
ratio along the length of the airfoil portion of the blade (Grabau). The prior
art also gives general guidance regarding the principles of load transfer from
a blade root to a hub and that such considerations effect selection of
materials for the blade root (Eyb ). However and as amply illustrated by the
Eyb reference, the engineering considerations that go into the design of an
airfoil differ from the considerations that go into the design of a blade root.
Namely, the design considerations of the relatively short blade root are more
focused on considerations attendant to the mechanical attachment of the
blade to the hub and are less focused on considerations attendant on the
aerodynamics of the relatively lengthy airfoil. Eyb, col. 1, 11. 5-20. Thus,
we consider it unlikely that a person of ordinary skill in the art would have
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been led take a metal fiber that is useful for reinforcing an airfoil and
concentrate its use to be the predominant reinforcing fiber in a blade root,
while another fiber is used as the predominant reinforcing fiber along the
length of the airfoil portion of the blade in a manner that transitions in fiber
concentration from one fiber to another along the length of the blade.
In summary, on the record before us, we are not persuaded that a
person of ordinary skill in the art would have had the requisite motivation to
modify a blade root so as to be predominantly reinforced with metal fibers
while more radial outward portions of the blade would be predominantly
reinforced with a second fiber. Consequently and in view of the foregoing,
we do not sustain the unpatentability rejection of claim 1.
Claims 3---8, 10, 11, and 14-16
These claims depend, directly or indirectly, from claim 1. Claims
App. As such, the Examiner's rejection of these claims suffers from the
same infirmity that was identified above with respect to claim 1. Thus, for
essentially the same reason expressed above in connection with claim 1, we
do not sustain the rejection of claims 3-8, 10, 11, and 14-16.
Unpatentability of Claim 9
over Sorensen, Grabau, Grabau '225, and Eyb
The rejection of claim 9, which depends from claim 1, suffers from
the same infirmity as the rejection of claim 1, which infirmity is not cured by
eliminating the Clearwater reference as one of the references in the proposed
combination. Claims App. Thus, for essentially the same reason expressed
above in connection with claim 1, we do not sustain the rejection of claim 9.
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Application 14/111,039
Unpatentability of Claims 12 and 13
over Sorensen, Grabau, Grabau '225, and Bech
These claims depend, directly or indirectly, from claim 1. Claims
App. The Examiner's rejection of these claims suffers from the same
infirmity that was identified above with respect to claim 1, which infirmity is
not cured by the Bech reference. Claims App. Thus, for essentially the
same reason expressed above in connection with claim 1, we do not sustain
the rejection of claims 12 and 13.
DECISION
The decision of the Examiner to reject claims 1 and 3-16 is reversed.
REVERSED
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