Ex Parte Tieu

Board of Patent Appeals and Interferences

Sep 27, 2007

10448725 (B.P.A.I. Sep. 27, 2007)

The opinion in support of the decision being entered
today is not binding precedent of the Board.

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte TRIET MINH TIEU
____________

Appeal 2007-3939
Application 10/448,725
Technology Center 2800
____________

Decided: September 27, 2007
____________

Before JOSEPH L. DIXON, HOWARD B. BLANKENSHIP,
and MAHSHID D. SAADAT, Administrative Patent Judges.

SAADAT, Administrative Patent Judge.

STATEMENT OF THE CASE
This is a decision on appeal under 35 U.S.C. §§ 134(a) and 6(b) from
the Examiner’s rejection of claims 1-6 and 8-19. Claims 7 and 20 have been
objected to by the Examiner for being dependant upon rejected claims but
otherwise allowable if rewritten in independent form to include all of the
limitations of the base claim and any intervening claim.
Appeal 2007-3939
Application 10/448,725

We affirm.
Appellant’s invention relates to a method and apparatus for accurately
detecting the position of a rotor in an electrically commutated brushless
direct current (dc) spindle motor such as the type used in a data storage
device to rotate a data recording disc (Specification 1). According to
Appellant, the inductive rise time (RT) exhibits an approximate linear
function with respect to the rotor’s position within the commutation state
(Specification 10). This approximate linear relationship, relative to the next
commutation point the rotor will encounter during rotation, is used to
calculate a substantially accurate position for the rotor (id.). An
understanding of the invention can be derived from a reading of exemplary
independent claims 1 and 9, which are reproduced below:
1. A method comprising:

developing a model of a motor based on a response of a
winding of the motor to an application of a non-rotational inducing
current across the winding for a predetermined time period; and

determining a substantially accurate position of a rotor of the
motor within a first commutation state of an electrical revolution of
the motor in which the rotor resides based on the model.

9. An apparatus adapted to determine a first commutation state of
a motor that a rotor of the motor resides and determine a substantially
accurate position of the rotor within the first commutation state.

The Examiner relies on the following prior art reference in rejecting
the appealed claims:
Calfee US 5,982,571 Nov. 9, 1999

2
Appeal 2007-3939
Application 10/448,725

The Examiner rejected claims 1-6 and 8-19 under 35 U.S.C. § 102(b)
as being anticipated by Calfee.
Rather than reiterate the opposing arguments, we refer to the Brief and
the Answer for the respective positions of Appellant and the Examiner.

ISSUE
The issue is whether Appellant has shown that the Examiner erred in
rejecting the appealed claims under 35 U.S.C. § 102(b) as anticipated by
Calfee.

FINDINGS OF FACT
The following findings of fact (FF) are relevant to the issue at hand.
1. Calfee relates to data recording disk drives and means for
releasing the disk drive carrier from the disk when the carrier is stuck to disk
surface (col. 1, ll. 6-11).
2. Calfee discloses that when the rotor becomes stuck, because the
position of the rotor relative to the phase windings at startup is not known,
inappropriate phase windings relative to the rotor may be energized,
generating magnetic fields that induce little or no torque to rotate the rotor
(col. 2, ll. 34-38).
3. In order to ensure that proper phase windings are energized,
Calfee uses sensing devices, such as Hall sensors, to determine the rotor
position relative to the windings at startup. Once the rotor position is
determined, appropriate windings can be energized to provide maximum
torque to the rotor. The rotor position can also be used to energize
3
Appeal 2007-3939
Application 10/448,725

appropriate windings to rotate the rotor in the correct direction every time.
However, such sensors must be precisely positioned and the sensor
components are expensive and take up physical space in the motor (col. 2, ll.
46-57).
4. Calfee provides for a method for accelerating the motor of the
disk drive from standstill to a threshold speed by determining a rotational
position of the rotor relative to the phase windings during a time period,
selectively establishing current paths through selected windings capable of
providing maximum torque to the rotor based on the rotational position of
the rotor and applying a current to the selected windings for a time period to
provide maximum torque to rotate the rotor (col. 5, ll. 39-52; col. 8, ll. 38-
42).
5. In order to start the spindle motor and free the slider in case of
stiction, the drive performs closed loop commutation of the spindle motor by
periodically sampling the rotor position, and then driving the spindle motor
by energizing appropriate phase windings relative to the rotor position that
provide maximum forward torque to the rotor (col. 8, ll. 21-31).
6. The rotor position detection (RPD) procedure uses indirect
inductance measurements to identify one of the six stable equilibrium
positions as the closest stable equilibrium position to the rotor's current
position (col. 11, ll. 32-36). The procedure includes the steps of measuring
the relative inductance of each phase winding by measuring the current rise
times in the phase winding in response to step voltages of opposite polarities
applied across the phase windings at, preferably, one rotor position (col. 11,
ll. 40-44).
4
Appeal 2007-3939
Application 10/448,725

7. Calfee further discloses that following the first millisecond
(msec), the drive current to the motor is cut off and the motor is allowed to
coast for approximately 2 msec to perform an RPD procedure by measuring
the rise time of the current in each phase pair. Once the commutation output
state is determined by the RPD procedure, the appropriate phase windings
are energized at full scale current to provide maximum forward torque to the
rotor until the next 12 msec RPD and commutation period (col. 14, ll. 15-
22).

PRINCIPLES OF LAW
A rejection for anticipation under section 102 requires that each and
every limitation of the claimed invention be disclosed in a single prior art
reference. See In re Paulsen, 30 F.3d 1475, 1478-79, 31 USPQ2d 1671,
1673 (Fed. Cir. 1994). Anticipation of a claim requires a finding that the
claim at issue reads on a prior art reference. Atlas Powder Co. v. IRECO
Inc., 190 F.3d 1342, 1346, 51 USPQ2d 1943, 1945 (Fed. Cir. 1999) (quoting
Titanium Metals Corp. v. Banner, 778 F.2d 775, 781, 227 USPQ 773, 778
(Fed. Cir. 1985)).

ANALYSIS
1. Claim 9
Appellant starts with claim 9 by arguing that although Calfee
determines the location of the rotor, a substantially accurate position of the
rotor is not determined (Br. 4). Appellant characterizes Calfee’s determined
equilibrium positions as an approximation of the rotor’s position and asserts
5
Appeal 2007-3939
Application 10/448,725

that such determination is not the same as determining a substantially
accurate position of the rotor, as claimed (id.). The Examiner argues that
Appellant has not specified the degree of accuracy for the claimed
determination of a substantially accurate rotor position (Answer 5). In that
regard, the Examiner asserts that determining the rotor position made by
Calfee is accurate enough to read on the broad language of claim 9 (id.).
We agree with the Examiner and find that the claimed term
“substantially accurate” lacks specific requirements as to how accurate the
position of rotor needs to be determined. As such, based on the broadest
reasonable interpretation of the claim, we find that the claimed “determining
a substantially accurate position of the rotor” is taught by Calfee. In view of
the analysis above, we find that Calfee prima facie anticipates claim 9 as the
reference teaches all the recited features. Additionally, Appellant argues
claims 10-19 together with the representative claim 9 (Br. 4) and thus,
allows these claims to fall with claim 9.

2. Claim 1
With respect to claim 1, Appellant argues that Calfee does not
disclose application of a non-rotational current, as required by claim 1 (Br.
4). Appellant refers to current value ITH as a percentage of IMAX and asserts
that Calfee does not show that ITH is a non-rotational inducing current (id.).
The Examiner responds by relying on the description of how an RPD
procedure is done during the time the drive current to the motor is cut off
and the motor is allowed to coast to characterize the applied current as a
non-rotational inducing current (Answer 5-6).
6
Appeal 2007-3939
Application 10/448,725

We agree with the Examiner’s characterization of measuring the
current rise as a part of the RPD during such period as applying a non-
rotational inducing current (FF 6-7). In that regard, the current applied to
energize the rotor, when the motor is coasting to perform the RPD
procedure, is not the same as the full scale current applied to provide the
forward torque to the rotor and, therefore, can be properly construed to be a
non-rotational inducing current.
Additionally, Appellant points to the limitation of claim 1 related to
“determining a substantially accurate position of the rotor” and presents
similar arguments discussed above with respect to claim 9. Thus, in view of
the analysis above and the teachings of Calfee related to determining the
position of the rotor, we find that Calfee prima facie anticipates claim 1, as
well as claims 2-6 and 8, which are argued together with representative
claim 1 (Br. 5).

CONCLUSION
On the record before us, the Examiner has made a prima facie case
that Calfee anticipates claims 1-6 and 8-19. 1 Therefore, in view of our

1 The Examiner rejected claims 1-20 under 35 U.S.C. § 112, second
paragraph for being indefinite and failure to recite method steps which lack a
relational correspondence among their elements (Final Rejection 2-3).
However, this rejection appears to be withdrawn in the Examiner’s Answer
which leaves these two claims as objected to for being dependent upon
rejected base claims, but probably considered allowable if rewritten to
include all of the limitations of their base claim and any intervening claims.

7
Appeal 2007-3939
Application 10/448,725

analysis above, we sustain the 35 U.S.C. § 102 rejection of claims 1-6 and 8-
19 as anticipated by Calfee. 2

DECISION
The decision of the Examiner rejecting claims 1-6 and 8-19 under
35 U.S.C. § 102 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)(1)(iv).

2 We observe that claims 1 and 9 recite method steps and functions to
be performed by an apparatus, describing mainly a concept without
indicating how the steps are implemented. These claims are merely drawn
to “disembodied abstract ideas,” which do not have any “real world effect”
until they are implemented. The absence of any transformation of physical
subject matter according to the definition of a process under 35 U.S.C.
§ 101, places these claims on the other side of the line defining statutory
subject matter. A case involving this issue is presently on appeal to the
Federal Circuit: In re Bilski, No. 2007-1130 (to be argued Oct. 1, 2007).
Additionally, in performing the method steps of claim 1, there is no
requirement that a computer be used. Therefore, the claimed subject matter
may be performed using only human intelligence, which has recently been
held to be non-statutory. In re Comiskey, No. 2006-1286, Slip Op. at 21
(Fed. Cir. Sep. 20, 2007). We do not need to reach the issue of whether
claims 1 and 9 encompass non-statutory subject matter since we affirm the
Examiner’s decision rejecting these claims. However, we encourage the
Examiner to consider patentability of the allowed claims 7 and 20, which are
dependent upon claims 1 and 9, under Section 101 in the event the
prosecution of these claims is reopened.
8
Appeal 2007-3939
Application 10/448,725

AFFIRMED

MDS

eld

David K. Lucente
Seagate Technology LLC
Intellectual Property - COL2LGL
389 Disc Drive
Longmont CO 80503
9