Ex parte LEE et al.

Board of Patent Appeals and Interferences

Aug 29, 2001

08364972 (B.P.A.I. Aug. 29, 2001)

The opinion in support of the decision being entered today was not written for
publication and is not binding precedent of the Board.
Paper No. 33
UNITED STATES PATENT AND TRADEMARK OFFICE
____________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
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Ex parte HAE-JOONG LEE and MYUNG-CHAN JEONG
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Appeal No. 1998-1819
Application No. 08/364,972
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HEARD: AUGUST 14, 2001
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Before RUGGIERO, LALL, and BLANKENSHIP, Administrative Patent Judges.
BLANKENSHIP, Administrative Patent Judge.
DECISION ON APPEAL
This is a decision on appeal under 35 U.S.C. § 134 from the examiner's final
rejection of claims 1-4, 7-12, 21, and 22.
We reverse.
Appeal No. 1998-1819
Application No. 08/364,972
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BACKGROUND
The invention is directed to a method and apparatus for providing impact
resistance to a hard disk drive. In particular, the invention serves to maintain a constant
flying height of the magnetic head over the disk. Representative claim 1 is reproduced
below.
1. A method of providing axial control and outside impact resistance for a hard
disk drive to maintain a normal flying height of a head by controlling a suspension of
said hard disk drive, said method comprising the steps of:
sensing one of a tensive state and a compressive state of said suspension,
said tensive state of said suspension indicating that a flying height of said head is
greater than said normal flying height, said compressive state of said suspension
indicating that said flying height of said head is less than said normal flying height;
generating a value indicative of an increase in reverse tensive force
necessary for application to said suspension to return said head to said normal
flying height when said tensive state of said suspension is sensed in said sensing
step; and
generating a value indicative of an increase in reverse compressive force
necessary for application to said suspension to return said head to said normal
flying height when said compressive state of said suspension is sensed in said
sensing step.
The examiner relies on the following references:
Sakamoto et al. (Sakamoto) 4,172,265 Oct. 23, 1979
Rynne et al. (Rynne) 4,950,936 Aug. 21, 1990
Good et al. (Good) 5,377,058 Dec. 27, 1994
Appeal No. 1998-1819
Application No. 08/364,972
1 The cover sheet of the Final Rejection and appellants’ “Status of Claims” section in the Brief and
Reply Brief, respectively, indicate that claims 15-20 have been rejected. However, no rejection has been
entered against the claims, and appellants did not reproduce claims 15-20 in the appendix of claims on
appeal. The Final Rejection, at page 2, appears to state the correct status of claims 15-20, i.e., that the
claims have been withdrawn from consideration.
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Claims 1-4 , 7, 10-12, 21, and 22 stand rejected under 35 U.S.C. § 103 as being
unpatentable over Good and Sakamoto. Claims 3, 4, 7, 21, and 22 were rejected over the
applied combination in a new ground of rejection set forth in the Examiner’s Answer.
Claims 8 and 9 stand rejected under 35 U.S.C. § 103 as being unpatentable over
Good, Sakamoto, and Rynne.
A rejection of claim 21 under 35 U.S.C. § 112, second paragraph was entered as
a new ground of rejection in the Answer, but withdrawn by the examiner upon entry of
appellants' amendment to the claim, filed Dec. 29, 1997.
Claims 5, 6, 13-20, and 23, subject to a restriction requirement, have been
withdrawn from consideration.1
We refer to the Final Rejection (Paper No. 15) and the Examiner's Answer (Paper
No. 23) for a statement of the examiner's position and to the Brief (Paper No. 22) and the
Reply Brief (Paper No. 25) for appellants’ position with respect to the claims which stand
rejected.
OPINION
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Application No. 08/364,972
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According to the statement of the rejection applied against instant claim 1 (Answer
at 3-4), Good reveals a method of fly height servo control of a read/write suspension.
Although Good does not disclose sensing tension and compression in the suspension,
Sakamoto is deemed to disclose a strain gauge 15 (Fig. 5) that provides a deflection
signal, enabling the system to track head position relative to the rest position.
Appellants argue, inter alia, that the combination is not well founded because
Sakamoto teaches tracking, rather than controlling flying height of a head. (Brief at 8.)
Additionally, appellants allege there is no teaching that the device of Good would
necessarily be improved by applying the teachings of Sakamoto. (Id. at 9.) Appellants
further allege (id. at 10) that the artisan would recognize that the "resistive wire" of
Sakamoto could not measure compression.
Good teaches adjusting fly height of read/write heads in multiple disk drives. The
reference discloses that the read signal for the fly height servo is picked up off the data
channel, and sampled by digitizing switching circuitry in Harmonic Ratio Fly height detector
(HRF) 28. See Good, Figs. 1, 5, and col. 3, ll 45-59. Circumferential variation in fly height
is corrected in real time by a PID controller. Radial variation in fly height is corrected by
feeding forward a correction from profile storage controller 32 during track seek
operations. Id. at col. 4, ll 1-9. A radial correction value for each head at each cylinder
position is determined during a calibration procedure. Id. at ll 19-28. Fly height correction
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is effected by piezoelectric film 40 (Fig.2) bonded to suspension arm 12, which bends arm
12 when a correction signal is applied. Id. at col. 5, ll. 20-30.
Sakamoto discloses a head tracking system for a rotary magnetic head in a
magnetic video tape recorder, which generates a deflection signal corresponding to the
deflection of the head from a rest position. The reference describes, in columns 1 and 2,
prior art methods of imparting a small oscillatory motion to the magnetic head via its
supporting element, which is typically a piezo-electric element or "bi-morph leaf." The
oscillatory motion is induced by applying a suitable drive signal which causes the
transducer to oscillate transversely about its normal oblique scanning path (e.g., Fig. 2).
The deviations from the path take the form of an amplitude modulation of the envelope of
the reproduced signals. An amplitude modulation detector provides a tracking error
signal, which is used in properly aligning the head transducer with the center of the track.
Mechanical vibrations of the bi-morph leaf were known to cause problems in
tracking control. Sakamoto teaches, to overcome unwanted frequency components due to
mechanical vibrations, securing a strain gauge 15 (Fig. 4) to bi-morph leaf 2. Deflection of
bi-morph leaf 2 thus generates a deflection signal indicating the extent and direction of
deflection of head 1 from its rest position. Sakamoto, col. 5, ll. 20-24 and 44-67. The
reference goes on to describe circuitry for compensating for the unwanted frequencies by
means of the deflection signal, so that the tracking control system may maintain the head
at the optimum tracking position.
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We do not find appellants' arguments regarding the alleged deficiencies of the
"resistive wire" of Sakamoto to be convincing. For one thing, Sakamoto at column 6, lines
18 through 22 makes clear that the strain gauge is not limited to the type employing a
"resistance wire." For another, Sakamoto discloses that direction of deflection of head 1
from its rest position is sensed, which suggests that strain gauge 15 responds differently to
tension and to compression. With no evidence provided in support of the position, we
consider appellants' argument to be untenable.
However, we are in ultimate agreement with appellants that the combined teachings
of the references fail to establish prima facie obviousness of the subject matter of instant
claim 1. Sakamoto is directed to a problem different from adjustment of fly height; namely,
overcoming mechanical vibrations which degrade tracking control, the tracking control
being effected by inducing an oscillatory motion in the supporting arm of a transducer.
Absent impermissible hindsight, we do not see how the teachings of Sakamoto would
have commended themselves to an artisan designing fly height servo control systems.
Moreover, appellants' arguments with respect to the lack of a rationale for the
proposed combination are well taken. The rejection asserts (Answer at 4) that the reason
for the combination would have been to provide more accurate tracking of the position of a
magnetic transducer. There is no factual support in the record for the position that the
servo system of Good would be improved by replacing or supplementing the HRF height
detector apparatus with a strain gauge, nor that the artisan would have recognized any
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improvement prospectively. While Good's system might indeed be improved if one were
to apply the teachings of Sakamoto, such an assumption would be mere speculation.
Rejections under section 103 cannot be founded on speculation.
We therefore do not sustain the rejection of claim 1, nor claims 2 and 21,
depending from 1, under 35 U.S.C. § 103 over Good and Sakamoto. Instant claims 3 and
7 add phase delay compensation to the combination, which includes sensing one of a
tensive and a compressive state of the suspension. Aside from the fact that the rejection
falls short for the reasons we have identified with respect to claim 1, we agree with
appellants that the deemed "inherency" (Answer at 6) of phase delay compensation
represents misallocation of the burdens in the patent examination process. Our reviewing
court has set out clear standards for establishing inherency, which have not been met in the
instant case.
To establish inherency, the extrinsic evidence "must make clear that the
missing descriptive matter is necessarily present in the thing described in
the reference, and that it would be so recognized by persons of ordinary
skill." "Inherency, however, may not be established by probabilities or
possibilities. The mere fact that a certain thing may result from a given set
of circumstances is not sufficient."
In re Robertson, 169 F.3d 743, 745, 49 USPQ2d 1949, 1950-51 (Fed. Cir. 1999)
(citations omitted).
We do not sustain the rejection of independent claims 3 and 7, nor of claims 4, 10-
12, and 22, each depending from claim 3 or 7. We also reverse the rejection of dependent
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claims 8 and 9. Rynne does not remedy the deficiencies with respect to Good and
Sakamoto as applied against base claim 7.
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CONCLUSION
The section 103 rejections of claims 1-4 , 7-12, 21, and 22 are reversed.
REVERSED
JOSEPH F. RUGGIERO )
Administrative Patent Judge )
)
)
)
) BOARD OF PATENT
PARSHOTAM S. LALL ) APPEALS
Administrative Patent Judge ) AND
) INTERFERENCES
)
)
)
HOWARD B. BLANKENSHIP )
Administrative Patent Judge )
Appeal No. 1998-1819
Application No. 08/364,972
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