Ex Parte Schwarz et al

Patent Trial and Appeal Board

Jan 18, 2018

13719859 (P.T.A.B. Jan. 18, 2018)

United States Patent and Trademark Office
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
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
13/719,859 12/19/2012 Frederick M. Schwarz 67097-2083PUS1; 1600
63542US01
54549 7590 01/22/2018
CARLSON, GASKEY & OLDS/PRATT & WHITNEY
400 West Maple Road
Suite 350
Birmingham, MI 48009
EXAMINER
LEGENDRE, CHRISTOPHER RYAN
ART UNIT PAPER NUMBER
3745
NOTIFICATION DATE DELIVERY MODE
01/22/2018 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):
ptodocket @ cgolaw. com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte FREDERICK M. SCHWARZ
and MICHAEL A. WEISSE
Appeal 2017-001746
Application 13/719,8591
Technology Center 3700
Before LINDA E. HORNER, JILL D. HILL, and THOMAS F. SMEGAL,
Administrative Patent Judges.
HORNER, Administrative Patent Judge.
DECISION ON APPEAL
STATEMENT OF THE CASE
Appellant seeks our review under 35 U.S.C. § 134(a) of the
Examiner’s decision rejecting claims 1-20. Final Office Action (November
23, 2015) (hereinafter “Final Act.”). We have jurisdiction under 35 U.S.C.
§ 6(b).
1 United Technologies Corporation (“Appellant”) is the applicant as
provided in 37 C.F.R. § 1.46 and is identified as the real party in interest.
Appeal Brief 1 (June 17, 2016) (hereinafter “Appeal Br.”).
Appeal 2017-001746
Application 13/719,859
We AFFIRM.
CLAIMED SUBJECT MATTER
Appellant’s claimed subject matter relates to a “lightweight shrouded
fan.” Specification 1, Title (filed December 19, 2012) (hereinafter “Spec.”).
Claims 1, 12, and 18 are the independent claims. Claim 1 is reproduced
below.
1. A gas turbine engine comprising:
a fan section including a fan with a plurality of fan blades
rotatable about an axis, wherein the plurality of fan blades
include a shroud; and
a speed change device in communication with the fan.
Appeal Br. 6 (Claims Appendix).
EVIDENCE
The Examiner’s decision relies upon the following evidence:
Howald US 3,556,675 Jan. 19, 1971
US 3,580,692
US 6,203,273 B1
US 2010/0005778 A1
US 7,694,505 B2
Mikolajczak
Weiner
Chaudhry
Schilling
May 25, 1971
Mar. 20, 2001
Jan. 14, 2010
Apr. 13, 2010
REJECTIONS
The Final Office Action includes the following rejections:
1. Claims 1-5, 7, 8, and 11-20 stand rejected under 35 U.S.C.
§ 103(a) as unpatentable over Schilling and Howald.
2. Claim 6 stands rejected under 35 U.S.C. § 103(a) as unpatentable
over Schilling, Howald, and Chaudhry.
2
Appeal 2017-001746
Application 13/719,859
3. Claim 9 stands rejected under 35 U.S.C. § 103(a) as unpatentable
over Schilling, Howald, and Mikolajczak.
4. Claim 10 stands rejected under 35 U.S.C. § 103(a) as unpatentable
over Schilling, Howald, and Weiner.
5. Claims 1 and 6 stand rejected under 35 U.S.C. § 103(a) as
unpatentable over Chaudhry and Howald.
ANALYSIS
First Ground of Rejection: Obviousness over Schilling and Howald
Appellant argues the claims subject to the first ground of rejection as a
group. Appeal Br. 3. Pursuant to 37 C.F.R. § 41.37(c)(l)(iv), we select
claim 1 as representative of the group, and claims 2-5, 7, 8, and 11-20 stand
or fall with claim 1.
The Examiner finds that Schilling discloses the gas turbine engine of
claim 1, except that it does not disclose the fan blades having a shroud.
Final Act. 3. The Examiner finds that Howald discloses a gas turbine engine
fan having blades with a shroud to provide damping action, and determines
that it would have been obvious to add Howald’s shroud to Schilling’s fan
blades for the same purpose. Id. at 4.
Appellant does not contest the Examiner’s findings as to the scope
and content of the prior art, or the differences between the prior art and the
claimed subject matter. Appellant also does not present any evidence of
secondary considerations of nonobviousness. Instead, Appellant contests
only the Examiner’s proposed modification of Schilling’s fan assembly with
Howald’s shroud. Appeal Br. 3. In particular, Appellant attacks the
Examiner’s stated reason for the proposed modification, arguing that “there
3
Appeal 2017-001746
Application 13/719,859
is no evidence that the fan blades 24 from Schilling experience damaging
vibrations that would lead one of ordinary skill in the art to make the
proposed modification.” Id.
We find ample disclosure in Howald to form the basis for the
Examiner’s determination that Howald suggests fan blades, such as those
disclosed in Schilling, would benefit from the addition of Howald’s shroud
in the same way as disclosed in Howald. In other words, we agree with the
Examiner that Howald suggests the proposed modification as an
improvement to the unshrouded fan blades of Schilling. Examiner’s Answer
13-14 (September 14, 2016) (hereinafter “Ans.”).
As noted by the Examiner and uncontested by Appellant, Schilling
discloses unshrouded turbine engine fan blades 24. Final Act. 3, Appeal
Br. 3, Schilling, Fig. 1. Each fan blade 24 extends radially outwardly from a
rotor disk 26. Schilling, col. 2,11. 7-8.
Howald pertains to improvements in bladed rotors of turbomachinery.
Howald, col. 1,11. 23-24. Howald discloses that a known problem in the art
is self-destruction of blades due to blade vibration excited by cyclic fluid
pressure perturbations that occur at the blades’ natural frequencies of
vibration. Id. at col. 1,11. 25-33. Howald states that this vibrational
problem is “generally applicable to all turbomachinery blades.” Id. at col. 2,
11. 4-5. Howald further discloses that a known solution to this problem is to
employ shrouds on the blades to increase the natural frequency of the blades
and provide damping action. Id. at col. 1,11. 56-60. Howald acknowledges
that a disadvantage of known part-span shrouds or tip shrouds is that such
shrouds increase the weight of the rotors. Id. at col. 1,11. 61-72. Howald
4
Appeal 2017-001746
Application 13/719,859
solves the vibrational problem by employing a shroud 26 having a socket
connected between the shroud 26 and the outer ends of the blades 24, which
connection “dampens the blades” and “substantially increases their natural
frequency by giving the blades support at both ends, as opposed to the
cantilevered mounting of the usual rotor blade.” Id. at col. 4,11. 7-13.
Further, Howald teaches that its shroud 26 “imposes no force loadings on the
rotor.” Id. at col. 4,11. 16-17.
Howald discloses benefits of using a shroud to increase the natural
frequency of turbomachinery blades so as to dampen vibrations, identified as
a problem experienced by all turbomachinery blades. Howald specifically
suggests that its shroud increases the natural frequency of the blades as
compared to rotor blades with a cantilevered mounting, such as the blades in
Schilling. As such, we find sufficient evidence to support the Examiner’s
finding that Howald would have suggested to one having ordinary skill in
the art that Schilling’s fan blades 24 would benefit from the addition of
Howald’s shroud, as proposed by the Examiner.
Appellant further asserts that “the proposed modification would
increase the rotating mass, which would negatively influence the engine
dynamics.” Appeal Br. 3. Appellant presents no objective evidence to
support the assertion that any increase in the rotating mass imparted by the
addition of a shroud, such as the shroud of Howald, would negatively
influence the engine dynamics. “Attorney’s argument in a brief cannot take
the place of evidence.” In re Pearson, 494 F.2d 1399, 1405 (CCPA 1974).
As noted above, Howald discloses benefits to the use of a shroud in damping
vibrations and further teaches a particular shroud construction that addresses
5
Appeal 2017-001746
Application 13/719,859
some of the drawbacks of an increase in weight that results from the use of
prior art shrouds. See Ans. 14 (“Howald’s use of a rotating blade shroud
despite an acknowledgement of such a weight-penalty is suggestion to one
having ordinary skill in the art that the associated advantages and
disadvantages can ultimately contribute a net benefit to the overall gas
turbine engine design.” [citations omitted]). As such, we are not convinced
by Appellant’s unsupported assertion that one having ordinary skill in the art
would not be led to employ Howald’s shroud on the fan blades of Schilling
due to the increase in rotating mass.
Appellant further contends that “the proposed combination is not
predictable and one of ordinary skill in the art would have no expectation of
successfully combining the references to achieve any particular benefit.”
Appeal Br. 3. Again, Appellant presents no objective evidence to support
the assertion of unpredictability. As noted by the Examiner, “Howald
discloses a working example of such a combination and the achieved benefit
of vibration damping resulting therefrom.” Ans. 15. This evidence
outweighs the unsupported assertions of unpredictability and no expectation
of success proffered by Appellant.
For these reasons, we sustain the rejection of claims 1-5, 7, 8, and 11-
20 under 35 U.S.C. § 103(a) as unpatentable over Schilling and Howald.
Second through Fourth Grounds of Rejection: Obviousness over Schilling,
Howald, and one of Chaudhry, Mikolajczak, and Weiner
Appellant relies on the arguments against the base combination of
Schilling and Howald as the basis for patentability of dependent claims 6, 9,
and 10, which are subject to the second through fourth grounds of rejection.
6
Appeal 2017-001746
Application 13/719,859
Appeal Br. 3—4 (Appellant arguing that the addition of either Chaudhry, or
Mikolajczak, or Weiner does not resolve the deficiencies with the base
combination of Schilling and Howald). Because we found no error in the
base combination proposed by the Examiner in the first ground of rejection,
we likewise sustain the second through fourth grounds of rejection of claims
6, 9, and 10.
Fifth Ground of Rejection: Obviousness over Chaudhry and l low aid
Appellant argues the claims subject to the fifth ground of rejection as
a group. Appeal Br. 4-5. Pursuant to 37 C.F.R. § 41.37(c)(l)(iv), we select
claim 1 as representative of the group, and claim 6 stands or falls with
claim 1.
The Examiner relies on the same teaching in Howald of using a
shroud to dampen vibrations in a gas turbine engine fan, as relied upon in the
first ground of rejection, for a proposed modification of Chaudhry’s gas
turbine engine in the fifth ground of rejection. FinalAct.il. Again,
Appellant does not contest the Examiner’s findings as to the scope and
content of the prior art or the differences between the prior art and the
claimed subject matter. And, Appellant does not present any evidence of
secondary considerations of nonobviousness. Instead, Appellant contests
only the Examiner’s proposed combination of Chaudhry and Howald for the
same reasons discussed above in the first ground of rejection. Appeal Br. 4.
For the reasons discussed above, we find no error in the Examiner’s
proposed modification of Chaudhry, and we find that the Examiner
articulated adequate reasoning based on rational underpinnings for the
7
Appeal 2017-001746
Application 13/719,859
combination. Accordingly, we sustain the fifth ground of rejection of
claims 1 and 6.
DECISION
The decision of the Examiner rejecting claims 1-20 is affirmed.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R.
§ 1.136(a)(l)(iv).
AFFIRMED
8