Ex Parte KAWABE et al

Board of Patent Appeals and Interferences

May 15, 2003

09530451 (B.P.A.I. May. 15, 2003)

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The opinion in support of the decision being entered
today was not written for publication in a law journal
and is not binding precedent of the Board.
Paper No. 16
UNITED STATES PATENT AND TRADEMARK OFFICE

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES

Ex parte NOZOMU KAWABE and TERUYUKI MURAI

Appeal No. 2003-0668
Application No. 09/530,451

ON BRIEF

Before KIMLIN, PAK and POTEATE, Administrative Patent Judges.
KIMLIN, Administrative Patent Judge.
DECISION ON APPEAL
This is an appeal from the final rejection of claims 1-9,
all the claims pending in the present application. Claims 1
and 7 are illustrative:
1. A highly fatigue-resistant steel wire comprising a
pearlite structure containing 0.8-1.0 mass % of C and 0.8-1.5
mass % of Si, wherein in the cross section of the steel wire an
average hardness in a region up to 100
m from the surface
thereof is at least 50 higher than that of an inner region based
on micro-Vickers hardness.
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7. A method of manufacturing a highly fatigue-resistant
steel wire comprising the steps of:
shaving a steel wire rod of pearlite structure containing
0.8-1.0 mass % of C and 0.8-1.5 mass % Si;
patenting the shaved wire rod;
drawing the patented wire rod into wire;
subjecting the resultant wire to strain relief annealing at
350-450° C without subjecting the same to quenching and tempering
process; and
shot peening the resultant wire.
The examiner relies upon the following references as
evidence of obviousness:
Yamao et al. (Yamao) 5,904,830 May 18, 1999
Takahashi (JP '833) 57-140833 Aug. 31, 1982
(Japanese patent)
Appellants' claimed invention is directed to a highly
fatigue-resistant steel wire comprising a pearlite structure, and
the method of manufacturing it. A surface region of the wire has
an average value of micro-Vickers hardness that is 50 higher than
the average value of an inner region. According to appellants'
specification,
it is a primary object of the present invention to
provide a steel wire and spring having a high thermal
resistance and a high fatigue strength that can be
produced without applying a quenching and tempering
process, namely, produced through a drawing process and
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Application No. 09/530,451
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a method of manufacturing such a steel wire and spring
[page 2, paragraph three].
Appealed claims 1-6 stand rejected under 35 U.S.C. § 103 as
being unpatentable over Yamao in view of JP '833. Appealed
claims 7-9 stand rejected under 35 U.S.C. § 103 as being
unpatentable over the same combination of references.
Upon careful consideration of the opposing arguments
presented on appeal, we will not sustain the examiner's
rejections.
We consider first the examiner's § 103 rejection of
claims 1-6. While Yamao discloses a method of making a steel
wire comprising amounts of C and Si which overlap the claimed
ranges, Yamao does not disclose that the steel wire has a cross
section having the presently claimed difference in average
hardness between the surface and inner regions. Cognizant of
this deficiency in the referenced disclosure, the examiner
reasons that since Yamao discloses making a steel wire that is
substantially similar to appellants' wire in composition and
methodology, one of ordinary skill in the art would have
reasonably expected the wire of Yamao to have the claimed
difference in hardness between the surface and inner regions. In
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essence, the examiner's reasoning is based on the principle of
inherency.
The flaw in the examiner's position, as emphasized by
appellants, is that the process of Yamao is not substantially the
same as appellants' process for making the steel wire. Whereas
Yamao exemplifies quenching and tempering steps for achieving a
steel wire having a tensile strength of at least 2,000 N/mm2,
appellants' process specifically excludes such quenching and
tempering steps. While it is the examiner's position that Yamao
"does not teach that the steel must be quenched and tempered,
only that it is possible" (page 8 of Answer, second paragraph),
appellants have properly noted that the examiner has pointed to
no specific disclosure in Yamao which indicates that the
quenching and tempering steps are optional. In relevant part,
Yamao discloses "[b]y subsequent quenching and tempering, steel
wires having the mechanical characteristics shown in Table 2 were
produced" (column 4, lines 16-18). Consequently, we cannot agree
with the examiner that the processes of Yamao and appellants are
so similar that one of ordinary skill in the art would have
reasonably expected that the wires produced by Yamao's process
would necessarily exhibit the claimed discrepancy in hardness
between the surface and inner regions. As for the examiner's
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reasoning that JP '833 would have motivated one of ordinary skill
in the art to modify the process of Yamao by eliminating the
quenching and tempering steps in order to avoid the delayed
fracture of the steel, we must agree with appellants that the
examiner has not established that one of ordinary skill in the
art would have been motivated to eliminate two of the exemplified
process steps of Yamao with the expectation of still achieving
the target tensile strength of at least 2,000 N/mm2. Appellants
have accurately pointed out that the process of JP '833 produces
wires having tensile strengths significantly lower than the 2,000
N/mm2 achieved by Yamao.
Concerning method claims 7-9, which contain the limitation
"without subjecting the same to quenching and tempering process,"
we find, for the reasons given above, that the examiner's stated
reason for modifying the process of Yamao requires the use of
impermissible hindsight. Also, although JP '833 discloses a
method of making a steel wire of pearlite structure comprising
the claimed steps of patenting, drawing and annealing, the
examiner has not demonstrated that it would have been obvious for
one of ordinary skill in the art to incorporate the claimed "shot
peening" into the method of JP '833.
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In conclusion, based on the foregoing, the examiner's
decision rejecting the appealed claims is reversed.
REVERSED
EDWARD C. KIMLIN )
Administrative Patent Judge )
)
)
)
)
CHUNG K. PAK ) BOARD OF PATENT
Administrative Patent Judge ) APPEALS AND
) INTERFERENCES
)
)
)
LINDA R. POTEATE )
Administrative Patent Judge )
ECK:clm
Appeal No. 2003-0668
Application No. 09/530,451
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