Ex Parte Leroy et al

Board of Patent Appeals and Interferences

Jun 29, 2012

11212777 (B.P.A.I. Jun. 29, 2012)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte JULIE LEROY and BERTRAND TARDY

____________

Appeal 2009-013436
Application 11/212,777
Technology Center 3600
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Before: NEAL E. ABRAMS, JENNIFER D. BAHR, and
STEVEN D. A. McCARTHY, Administrative Patent Judges.

ABRAMS, Administrative Patent Judge.

DECISION ON APPEAL
STATEMENT OF THE CASE
Julie Leroy et al. (Appellants) seek our review under 35 U.S.C. § 134
of the final rejection of claims 1and 4-12, which are all the claims remaining
in the application. We have jurisdiction under 35 U.S.C. § 6(b).
We REVERSE.
THE INVENTION
The Appellants’ invention is directed to an on-board device for
measuring the mass and the position of the center of gravity of an aircraft.
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Claim 1, reproduced below, is illustrative of the subject matter on
appeal.
1. An on-board device for measuring the
mass and the position of the center of gravity of an
aircraft having a plurality of landing gears, each
landing gear being provided with at least one
contact member, said device comprising:
a hollow deformable element
connected to a respective contact member, said
deformable element is deformable under the
action of the weight of the aircraft when the
aircraft is standing on a surface;
a bar arranged inside said deformable
element; and
an eddy current sensor attached to a
free end of said bar,
wherein said sensor measures a
distance between itself and a face of said
deformable element.

THE PRIOR ART
The Examiner relies upon the following as evidence of
unpatentability:

Kliever US 3,488,997 Jan. 13, 1970
Eckerle US 4,977,784 Dec. 18, 1990
Lindberg et al. US 5,521,827 May 28, 1996
Pradier US 7,089,791 B2 Aug. 15, 2006

THE REJECTIONS
The following Examiner’s rejections are before us for review:
Claims 1, 4-6, 11 and 12 stand rejected under 35 U.S.C. § 103(a) as
being unpatentable over Kliever in view of Eckerle.
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Claims 7-9 stand rejected under 35 U.S.C. § 103(a) as unpatentable
over Kliever in view of Eckerle and further in view of Lindberg.
Claim 10 stands rejected under 35 U.S.C. § 103(a) as unpatentable
over Kliever in view of Eckerle and further in view of Pradier.
OPINION
Claim 1 is directed to an on-board device for measuring the mass and
the position of the center of gravity on an aircraft having a plurality of
landing gears, each landing gear having a contact member (defined by the
Appellants as wheels 2 of the aircraft) (Spec. 5, lines 8-9) . The device
comprises a hollow deformable member connected to a respective contact
member and deformable under the weight of the aircraft when the aircraft is
standing on a surface, a bar arranged inside the deformable element, and an
eddy current sensor attached to a free end of the bar, wherein the sensor
measures a distance between itself and a face of the deformable element.
The Examiner has taken the position that all of the subject matter
recited in independent claim 1 is disclosed in Kliever, except for the eddy
current sensors. However, the Examiner has concluded that it would have
been obvious to substitute an eddy current sensor for the sensor disclosed in
Kliever in view of Eckerle, which discloses an eddy current sensor being
utilized in a system for accomplishing the same objective as Kliever, albeit
in a different manner. In this regard, the Examiner points to Kliever’s
statement that the sensor “may be any sensor which produces an output
signal proportional to the displacement of the sensor bar (see column 5, lines
45-55)” (parentheses in the original), and then states that motivation for such
a modification by one of ordinary skill in the art constitutes “the mere
substitution of known types of sensors within the same environment in order
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to produce the same types of measurements.” Ans. 3. Placing the sensor on
the bar, as recited in the claim, would in the Examiner’s view have been
obvious “in light of the limited number of places it could be placed” and
“the normal and obvious engineering practice of determining which of the
two positions would be optimum for a given structure.” Ans. 3.
Among the several arguments set forth by the Appellants in rebuttal to
the Examiner’s conclusion is that whereas Kliever discloses a sensor that
provides an output directly proportional to the relative displacement of a
sensor bar from a point on the inner surface of the deformable axle within
which it is mounted, the Eckerle eddy current sensor measures the frequency
of vibration of a wire that stretches under load, and therefore it would not
have been obvious to one of ordinary skill in the art to replace the
displacement measuring sensor of Kliever with the vibration frequency
measuring eddy current sensor of Eckerle. Reply Br. 2-3.
Like the Appellants’ invention, the Kliever system has as its objective
determining the true weight and center of gravity of an aircraft. Col. 1, lines
69-71. Also like the Appellants’ invention, Kliever measures the deflection
present in a hollow deformable element (axle) 12 that is connected to a
contact member (strut) 14. Rigidly mounted on the inside centerline of
hollow deformable element 12 is a sensor bar 25, at the free end of which is
an adapter 40. An arm 29 is mounted on the inside surface of deformable
element 12, spaced radially from adapter 40. A sensor 31 is attached to arm
29, and a movable probe 38 extends from sensor 31 into contact with the
upper surface of adapter 40. As the distal portion of element 12 deforms in
response to the weight of the aircraft (upwardly as shown in Fig. 1), the
distance between adapter 40 and arm 29 increases, and the magnitude of this
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increase is sensed by sensor 31 through the movement of probe 38. From
this information, the weight and, in concert with like sensing systems on
each of the other landing gears, the center of gravity of the aircraft, can be
determined. Fig. 1; col. 5, lines 41-70. While Kliever illustrates a
measuring system that utilizes a movable probe and a dial indictor, the
reference further states that “sensor devices 30, 31 are shown as dial
indicators in FIG. 1 but it will be understood that they may also be strain
gauges, gauged displacement sensors, differential transformers or any other
force or movement transducers which will provide an output directly
proportional to the relative displacement between the sensor bar 25 and the
point of attachment of the sensors 30, 31 on the axle as measured at a and
b.” Col. 5, lines 50-54.
Eckerle discloses a system in which the load on a vehicle axle is
determined “by measuring the resonant frequency of a vibrating string [or
wire] attached to the axle or spindle to thereby determine the tension on the
string which is related to the load on the axle or spindle.” Col. 3, lines 24-
28. Fig. 3 shows an embodiment in which the load on each spindle can be
measured. Col. 5, lines 53-55. In this embodiment, a wire 70 is attached at
one end a spindle 20 at an attachment point 14 and is immovably fixed at its
opposite end to a wire carrier 76 on a support 74 mounted on the inside
surface of axle 22. Attachment point 14 is on the center axis of spindle 20,
while point 76 is spaced radially from the center axis. Vibration inducing
means 40 causes wire 70 to vibrate, and frequency sensor means 50 is used
to determine the resonant frequency of the vibrating wire. Col. 5, lines 53-
66. Deflection of spindle 20 (illustrated by the dashed line in Fig. 1) will
result in a change of the length of wire 70 which, in turn, will result in a
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change in tension of the wire, thereby changing its resonant frequency. Col.
3, lines 58-63. The tension of the wire is related to the load on the spindle,
and thus the load can be calculated. Col. 2, lines 34-41. Among the devices
disclosed by Eckerle for sensing the frequency of vibration of the wire are
“electronic means such as any number of . . . proximity sensors operating on
optical, capacitive, magnetic, or eddy-current principles.” Col. 4, lines 31-
34.
As explained above, the system disclosed in Kliever determines the
load on an aircraft support wheel axle by directly measuring the magnitude
of the deflection of the axle with regard to a sensor bar rigidly affixed at the
centerline of the axle. Several means for doing so are recited, with the
proviso that they will provide “an output directly proportional to the relative
displacement between the sensor bar 25 and the point of attachment of the
sensors 30, 31 on the axle.” Col. 5, lines 52-55; emphasis added. An eddy
current sensor is not one of the means mentioned in Kliever to accomplish
this task. However, it is the Examiner’s position that in view of Eckerle’s
disclosure of using an eddy current sensor in his system it would have been
obvious to “have the eddy current sensor placed on the bar to measure
displacement of the deformable element” in the Kliever system (Ans. 3).
The Examiner responds to the Appellants’ arguments to the contrary by
stating that by measuring the frequency of the string the eddy current sensor
inherently measures the displacement of the string. Ans. 6. We do not agree
with the Examiner’s reasoning or conclusion.
The sensing system disclosed in Eckerle does not utilize a sensor bar,
so it cannot measure the displacement between a sensor bar and the point of
attachment of the sensor on the axle nor, therefore, can it provide an output
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proportional to the measurement of that displacement, as is required in the
Kliever system. While Eckerle teaches one of ordinary skill in the art to
utilize an eddy current sensor to determine the frequency of vibrations of the
stretched wire, the reference does not teach or suggest that an eddy current
sensor also can be used to measure the distance between, or provide an
output proportional to, the relative displacement between a sensor bar and
the point of attachment of the sensor to the axle. Moreover, the Examiner
has not provided any evidence that an eddy current sensor used to measure
frequency of vibrations of a taut wire also is capable of measuring the
displacement between a rigid bar and the deformable housing in which it is
located. Thus, from our perspective, the evidence before us does not provide
support for the Examiner’s conclusion that one of ordinary skill in the art
would have been motivated to modify the Kliever system in the manner
proposed by the Examiner, that is, to discard the sensor utilized in the
Kliever system and replace it with the sensor of the Eckerle system, even
though the two sensors operate on significantly different principles. In
addition, to the extent that the Examiner might be suggesting that the entire
Eckerle sensing system be substituted for the Kliever system, doing so
would necessitate discarding the Kliever sensor bar, a component which is
fundamental to the Kliever system, as well as being recited in all of the
Appellants’ claims.
Based upon the reasoning expressed above, we reverse the rejection of
independent claims 1, 11 and 12 and dependent claims 4-6, which stand
rejected as being unpatentable over Kliever in view of Eckerle.
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The addition of the teachings of Lindberg fails to overcome the
deficiencies noted above with regard to Kliever and Eckerle, and therefore
we also will reverse the rejection of claims 7-9, which depend from claim 1.
Pradier also does not overcome the deficiencies in Kliever and
Eckerle, and thus the rejection of claim 10, which depends from claim 1, is
reversed.

REVERSED

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