Ex Parte Lund et al

Patent Trial and Appeal Board

Jul 26, 2018

14122215 (P.T.A.B. Jul. 26, 2018)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO.
14/122,215
81598 7590
Mark Ussai
SKF USA Inc.
890 Forty Foot Road
PO Box 352
Lansdale, PA 19446
FILING DATE FIRST NAMED INVENTOR
03/20/2014 ThoreLund
07/30/2018
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.
2012P00045WOUS 2243
EXAMINER
DUNN, COLLEEN P
ART UNIT PAPER NUMBER
1736
NOTIFICATION DATE DELIVERY MODE
07/30/2018 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):
ipr@skf.com
mark.ussai@skf.com
bryan. peckj ian @skf.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE
THE PATENT TRIAL AND APPEAL BOARD
Ex parte THORE LUND 1
and Tobias Meyer
Appeal2017-010730
Application 14/122,215
Technology Center 1700
Before MARK NAGUMO, A VEL YN M. ROSS, and LILAN REN,
Administrative Patent Judges.
NAGUMO, Administrative Patent Judge.
DECISION ON APPEAL
Aktiebolaget SKF ("SKF") timely appeals under 35 U.S.C. § 134(a)
from the Final Rejection2 of all pending claims 1-18 and 22. (FR 3.)
We have jurisdiction. 35 U.S.C. § 6.
We affirm.
1 The applicant under 37 C.F.R. § 1.46, and hence the appellant under
35 U.S.C. § 134, is the real party in interest, identified as Aktiebolaget SKF.
(Appeal Brief, filed 28 April 2017 ("Br."), 1.)
2 Office Action mailed 29 November 2016 ("Final Rejection"; cited as
"FR").
Appeal2017-010730
Application 14/122,215
A. Introduction 3
OPINION
The subject matter on appeal relates to an improved method for heat-
treating carbonitrided steel, which, although stronger and harder, is more
susceptible to cracking in certain high stress applications such as bearings in
wind turbines than non-carbonitrided steels. (Spec. 1, 11. 19-31.)
The initial treatment steps are illustrated in Figure 1, below.
T
/
-------------------t
{Fig. 1: initial steps of carbonitriding, cooling, reheating, and quenching}
In step a), the steel sample is brought to a temperature of 930-970°C
(to the austenitic phase) in the presence of, e.g., methane-ethane-propane
(for carbon) and ammonia (for nitrogen). (Id. at 7, 11. 18-21.) The high
temperature is said to ensure that all carbides are dissolved. (Id. at 2, 11. 2-
3.) In step b ), the sample is cooled below the A 1 transformation temperature
(the lowest temperature at which the austenite phase exists in equilibrium).
3 Application 14/122,215, Method and steel component, filed 20 March
2014, as the national stage under 35 U.S.C. § 371 of PCT/SE2012/000079,
filed 22 May 2012. We refer to the '"215 Specification," which we cite as
"Spec."
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Appeal2017-010730
Application 14/122,215
In step c), the steel is reheated to 780-820°C (to the austenite phase), and in
step d) the steel is quenched "to achieve the full case hardness."
(Id. at 11. 31-34.)
The '215 Specification teaches that in the prior art, "[ s ]teel is firstly
austenitized and then quenched. The steel is then isothermally tempered by
heating at a temperature just above the martensite formation temperature
(Ms)." (Id. at 8, 11. 7-9.) The step of isothermal tempering is illustrated in
Figure 2, reproduced below, right. As shown, at successively lower
temperatures i, ii, and iii,
the hardness of the bainite-
transformed steel increases,
but it takes ever longer
(note that the horizontal
time scale is logarithmic) to
start (Bs) and to finish (Bf)
the process.
PRIOR ART
log Tin1e
{Figure 2 shows a prior art isothermal bainite-transformation process}
Two alternative improvements to the prior art isothermal tempering are
revealed: step e), in Figure 3 (left); and step f), in Figure 5 (right), below.
I~_)
Temperature
Ms 1--~....;.;.;,;;;,;.;.;.::.:.::.;;;:::,,;.:.:.;~.;..;.;..;.;.;:,..
60HRC j 60 HRC
log Time
Ti~ain
{Fig. 3: shorter time, about as hard
~,;h•,v,,,..-,~.-c-.... ..,,,,. ... ..,_..,,,,..,..,...,... ......... ~ • ..._ .... ,,. ......... V,, .. ',...,......,,.,.......,... ............................... _ ....... ......,, ................... .
Temp j ;
Jog Ti.m~
Fig 5, same time, harder}
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Appeal2017-010730
Application 14/122,215
In method step e ), the steel, which has already been austenitized and
quenched (Spec. 8, 11. 17-19), is brought to a temperature slightly above the
martensite transition temperature, Ms, and is then held at that temperature
after the transition to bainite begins at Bs. (Id. at 11. 20-22.) After some
large fraction of the bainite transition is completed, the temperature is raised
as indicated in Figure 3 to a level at which the bainite transformation is
completed quickly at Bf. (Id. at 11. 22-23.) The resulting steel is said to be
almost as hard, but to be obtained in a significantly shorter time (note that
the time axis is logarithmic). (Id. at 11. 23-25.)
Alternative method step f) is said to be "based on the insight that the
martensite formation temperature (Ms) decreases during the bainite
transformation at that this may be utilized to lower the bainite transformation
temperature to a temperature below the initial martensite formation
temperature (Ms) during the bainite transformation in order to form harder
bainite." (Spec. 3, 1. 32-3, 1. 2.) Thus, after the steel has been austenitized
and quenched (id. at 8, 11. 32-34), the steel is transformed to a certain extent
to bainite (e.g., 15--40%; (id. at 4, 11. 4--5)) at a temperature above the initial
martensite transformation temperature, Ms, the temperature is lowered
below Ms, but still be above the (now lower) temperature of transition to
martensite. Thus, in the words of the Specification, the "[ m ]artensitic
transformation is avoided at all times." (Id. at 2, 11. 22-23.) The resulting
bainite will be correspondingly harder, and the temperature may be raised
back to a temperature above the initial Ms to complete the bainite
transformation in the same overall period of time. (Id. at 11. 10-12.)
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Appeal2017-010730
Application 14/122,215
Claim 1 is representative and reads:
A method for heat treating a steel component comprising the
steps of:
a) carbonitriding the steel component at a temperature
of 930-970°C
b) cooling the steel component,
c) re-heating the steel component to a temperature
of 780-820°C and
d) quenching the steel component,
wherein the method further comprises one of the
following steps
e) performing a bainite transformation at a temperature
above the martensite formation temperature,
or
transforming 25-99% of the austenite into bainite at
that temperature and then
increasing the temperature to speed up the
transformation of the remaining austenite into bainite,
f) holding the steel component at an initial
temperature (T 1) above the initial martensite formation
temperature (Ms), and
lowering the initial temperature (T 1) to a
temperature (T 2) that is below the initial martensite
formation temperature (Ms) but above the actual
martensite formation temperature during the bainite
transformation.
(Claims App., Br. 10; some indentation, paragraphing, and emphasis added.)
Remaining independent claim 22 is similar, but requires expressly the
sequence of steps recited in claim 1. (Id. at 12-13.)
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Appeal2017-010730
Application 14/122,215
The Examiner maintains the following grounds of rejection 4, 5 :
A. Claims 1-8 and 22 stand rejected under 35 U.S.C. § I03(a) in
view of the combined teachings of Maezawa, 6 ASM, 7 and
Lund '743 8 (step e) or Volkmuth9 (step f).
Al. Claims 9-18 stand rejected under 35 U.S.C. § I03(a) in view
of the combined teachings of Maezawa, ASM, and either
(Lund '743 or Volkmuth) and Lund '867. 10
B. Claims 1-8 and 22 stand rejected under 35 U.S.C. § I03(a) in
view of the combined teachings of Beswick, 11 and either
(Lund '743 or Volkmuth).
Bl. Claims 9-18 stand rejected under 35 U.S.C. § I03(a) in view
of the combined teachings of Beswick, and either (Lund '743
or Volkmuth) and Lund '867.
4 Examiner's Answer mailed 14 June 2017 ("Ans.").
5 Because this application has an effective filing date before
the 16 March 2013, effective date of the America Invents Act, we refer to
the pre-AIA version of the statute.
6 Tatsu Maezawa, Heat-treatment method for steel, JP 2009-052119 A
(2009) (translation by Patent Translate (EPO & Google) (2016
7 ASM E9310 datasheet,
visited June 3, 2016.
8 Thore Lund et al., Method of complete bainite hardening, U.S. Patent
No. 6,149,743 (2000).
9 Johann Volkmuth and Martin Goebel, Process for heat treatment of steel
or cast iron workpieces, U.S. Patent Application Publication
2008/0190522 Al (2008).
10 Thore Lund and Ingemar Strandell, Bearing component,
WO 2010/134867 Al (2010).
11 John Michael Beswick et al., Wear- and fracture-resistant steel,
WO 00/77265 Al (2000).
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Appeal2017-010730
Application 14/122,215
C. Claims 1-18 and 21 [sic: 22] stand rejected under provisional
obviousness-type double patenting in view of claims 1-7 of
14/111,693. 12
B. Discussion
The Board's findings of fact throughout this Opinion are supported by
a preponderance of the evidence of record.
Rejection C, provisional obviousness type double patenting
SKF waives expressly substantive argument in this appeal against
rejection in view of the claims of the co-pending application (Br. 9, § E), so
we summarily affirm this rejection.
Rejections A and B: obviousness
SKF does not dispute the Examiner's determination that steps a)
through d) of claim 1 read on the steps disclosed by Maezawa, or that step e)
reads on the disclosure of Lund '743. Rather, SKF points to the quenching
step of Maezawa and asserts that martensite will be formed as a result.
(Br. 3., 11. 15-17.) SKF urges (id. at 4, 11.14--22) that Lund '743 teaches that
"[b ]ainite hardening is sometimes preferred in steels compared to martensite
hardening." (Lund '743, col. 1, 11. 9-10.) SKF urges that Lund '743
discloses two different steel hardening processes, but that "the art does not
show that either is clearly better for all bearing applications." (Br. 5, 11. 4--
6.) Moreover, in SKF's view, "nothing [in the record] suggests that steel
12 Staffan Larsson and Peter Neuman, Method of heat treating a steel
component, U.S. Application 14/111,693, filed 14 October 2013, is pending
as of the date of this Decision.
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Appeal2017-010730
Application 14/122,215
should be first hardened by a martensite hardening process and that a second
hardening process should then be performed on this already-hardened steel."
(Id. at 11. 7-9.) Thus, SKF argues, the Examiner has not shown any proper
reasoning for combining the references.
These arguments are not well-taken. SKF describes the process of
bainite hardening disclosed by Lund '743 as an improvement on the
conventional process of isothermal tempering "by heating at a temperature
just above the martensite formation temperature (Ms)." (Spec. 8, 11. 6-9.)
Moreover, Maezawa discloses that the quenched steel is tempered by heating
to tempering temperature T4, between 150°C and 220°C, for
example 180°C. (See Maezawa, Figure 8 and 15 [0043] (first embodiment,
carbiding treatment); Figure 9 and 16 [0048] (second embodiment,
carbonitriding treatment).) Thus, the rejection maintained by the Examiner
is merely the substitution of an improved method of bainite tempering
known to the prior art for a standard method, disclosed by Maezawa, of
tempering applied to an already quenched austenitic steel. Put another way,
the combined teachings ofMaezawa and Lund '743 provide both the
motivation and the reasonable expectation of success required for a prima
facie case of obviousness. See, e.g., In re Dow Chemical Co., 837 F.2d 469,
473 (Fed. Cir. 1988) ("Both the suggestion and the expectation of success
must be founded in the prior art, not in the applicant's disclosure.").
SKF also criticizes the Examiner's finding that Volkmuth discloses
steps corresponding to step f). As SKF points out, "Volkmuth's figures all
depict an austenitizing phase followed by a temperature decrease to a level
that always remains above the martensite start temperature." (Id. at 4, 11. 29-
30.) The weight of the evidence supports SKF in this matter. However, the
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Appeal2017-010730
Application 14/122,215
error by the Examiner is harmless because in every claim before us, both
steps e) and f) are alternative options. Thus, every claim can be rendered
obvious by a disclosure of step e) that can be combined properly with
disclosures of steps a) through d).
SKF does not raise substantively distinct arguments for the
patentability of the remaining claims. In particular, SKF dismisses
Rejections B and B 1 based on Beswick as merely cumulative with
Rejections A and Al based on Maezawa. (Br. 8, § C.)
Finally, we observe that SKF does not raise arguments for
patentability based on so-called secondary considerations, such as
unexpected results.
We therefore affirm the appealed rejections.
C. Order
It is ORDERED that the rejection of claims 1-18 and 22 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).
AFFIRMED
9