Ex Parte DU et al

Board of Patent Appeals and Interferences

Aug 22, 2003

09019871 (B.P.A.I. Aug. 22, 2003)

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publication and is not binding precedent of the Board.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. 43
UNITED STATES PATENT AND TRADEMARK OFFICE
____________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________
Ex parte HUNG T. DU and TODD A. HAGAN
____________
Appeal No. 2003-0025
Application No. 09/019,871
____________
Heard : July 16, 2002
____________
Before RUGGIERO, DIXON, and SAADAT, Administrative Patent Judges.
DIXON, Administrative Patent Judge.
DECISION ON APPEAL
This is a decision on appeal from the examiner's final rejection of claims 1, 5-9,
11, 12, and 17-20. Claims 3, 4, 14, and 15 are objected to by the examiner as
allowable if rewritten. Claims 2, 10, 13 and 16 have been canceled.
We AFFIRM.
Appeal No. 2003-0025
Application No. 09/019,871
2
BACKGROUND
Appellants’ invention relates to a brush assembly for a power tool to apply bias at
substantially constant force directly onto a brush surface. An understanding of the
invention can be derived from a reading of exemplary claim 1, which is reproduced
below.
1. A brush assembly for an electric motor comprising:
a base, said base including a member for securing said base with a
motor spider assembly;
a brush housing associated with said base, said housing having
first and second open ends;
a brush, defining a longitudinal axis, movably positioned in said
housing between said first and second open ends, and said brush
extending from one of said open ends of said housing, said brush
including a surface, and a recessed portion, said recessed portion
including said surface, said surface being at a desired angle with respect
to the brush longitudinal axis;
a biasing member exerting a substantially constant force directly on
said brush surface in the direction of the longitudinal axis for biasing said
brush into electrical contact with a commutator; and
an electrical connector electrically coupled with said brush for
electrical connection between the commutator and a power supply.
The prior art references of record relied upon by the examiner in rejecting the
appealed claims are:
Sekyra 2,194,620 Mar. 26, 1940
Cousins et al. (Cousins) 4,593,220 Jun. 03, 1986
Peot et al. (Peot) 5,907,207 May 25, 1999
Appeal No. 2003-0025
Application No. 09/019,871
3
(Filed Nov. 7, 1997)
Sugai et al. (Sugai) 6,031,313 Feb. 29, 2000
(Filed Dec. 8, 1997)
Claims 1 and 5-8 stand rejected under 35 U.S.C. § 103 as being unpatentable
over Sugai in view of Peot. Claims 9, 11, 12, 17, 18, and 20 stand rejected under
35 U.S.C. § 103 as being unpatentable over Sugai in view of Peot and Sekyra. Claim
19 stands rejected under 35 U.S.C. § 103 as being unpatentable over Cousins in view
of Sugai and Peot.
Rather than reiterate the conflicting viewpoints advanced by the examiner and
appellants regarding the above-noted rejections, we make reference to the examiner's
answer (Paper No. 32, mailed Jun. 21, 2002) for the examiner's reasoning in support of
the rejections, and to appellants’ brief (Paper No. 31, filed Mar. 25, 2002) and reply
brief (Paper No. 33, filed Aug. 26, 2002) for the appellants’ arguments thereagainst.
OPINION
In reaching our decision in this appeal, we have given careful consideration to
appellants’ specification and claims, to the applied prior art references, and to the
respective positions articulated by appellants and the examiner. As a consequence of
our review, we make the determinations which follow.
At the outset, we note that appellants have elected to group all of the dependent
claims with their respective independent parent claims. (See brief at page 3.)
Additionally, appellants’ include the claims objected to in their second group as standing
Appeal No. 2003-0025
Application No. 09/019,871
4
or falling with independent claim 9. We will not include these claims in the second
group since they have not been rejected by the examiner and this issue is not before
us. Therefore, we will address claims 1, 9, and 19 as the representative claims for
each of the three groups and address appellants’ arguments thereto.
35 USC § 103
To reject claims in an application under section 103, an examiner must
show an unrebutted prima facie case of obviousness. See In re Deuel,
51 F.3d 1552, 1557, 34 USPQ2d 1210, 1214 (Fed. Cir. 1995). In the
absence of a proper prima facie case of obviousness, an applicant who
complies with the other statutory requirements is entitled to a patent. See
In re Oetiker, 977 F.2d 1443, 1445, 24 USPQ2d 1443, 1444 (Fed. Cir.
1992). On appeal to the Board, an applicant can overcome a rejection by
showing insufficient evidence of prima facie obviousness or by rebutting
the prima facie case with evidence of secondary indicia of
nonobviousness. In re Rouffet, 149 F.3d 1350, 1355, 47 USPQ2d 1453,
1455 (Fed. Cir. 1998).
The examiner maintains that Sugai teaches the claimed invention, but for the
biasing member exerting a substantially constant force on the brush surface and that
Poet teaches a biasing member exerting a substantially constant force on the brush
surface for increasing the brush life. The examiner maintains that both references are
“from the same field of endeavor” and that the “purpose disclosed by one inventor
would have been recognized in the pertinent art of the others.” (See answer at pages
4-5.) While we are not exactly sure what the examiner means by the second part of the
motivation statement, we are of the reasoned opinion that optimizing the electrical and
mechanical life of the brush would have been quite a desirable goal as taught by Poet
Appeal No. 2003-0025
Application No. 09/019,871
1 We note that claim 1 does not recite any specific details or specifications of the motor or its
specific field of use.
5
at columns 1 and 2 and in Fig. 2. We agree with the examiner that it would have been
obvious to one of ordinary skill in the art in light of the teachings of Poet regarding the
use of a constant or substantially constant force in the longitudinal direction to optimize
the life of an electric motor brush.1 Here, we find that the examiner has addressed the
limitations of independent claim 1, identified the deficiencies in the prior art and
provided a convincing line of reasoning why it would have been obvious to one of
ordinary skill in the art to combine the teachings of Poet with Sugai. Therefore, we find
that the examiner has established a prima facie case of obviousness and the burden
shifts to appellants.
The examiner maintains that the motivation to apply the constant force in Poet is
that Poet teaches exerting a substantially constant force (Fig. 3) directly on the brush
for the purpose of increasing the brush life. (See answer at pages 4, 6, and 9.) The
examiner relies on Figures 1 and 3 of Poet to teach this substantially constant force, but
neither of these figures provides any clear teaching or suggestion of increasing the life
of the brush. We do find that Figure 2 teaches the use of an optimal pressure P0 which
reduces the rate of total (mechanical and electrical) brush wear and col. 2 teaches that
“maintaining of a constant optimal pressure between the brush and the commutator of
an electric motor, resulting in longer life for the brush of the electric motor.”
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Application No. 09/019,871
6
Appellants argue that the combination of prior art references does not teach or
suggest the claimed invention and the examiner is misapplying the references and
applying hindsight to reconstruct applicants’ invention. (See brief at page 4.)
Appellants argue that claim 1 requires that the biasing member exerts a substantially
constant force directly on the brush surface in the direction of the longitudinal axis of
the brush. Appellants argue that Sugai teaches that the spring force applied on the
compound angled surface is to prevent wild behavior of the brush to prohibit shutter or
noise of the brush. (See brief at page 4.) Appellants argue that the examiner relies
upon the teachings of Poet to teach the use of a constant force on the brush and that
this constant force would minimize the wear on the brush. (See brief at page 4.)
Appellants argue that the two references are directed to different problems and that the
examiner has merely extracted the one element from Poet concerning constant force
and applied it using hindsight in combination with Sugai. (See brief at page 5.) We do
not find appellants’ arguments to be persuasive since we find that optimizing the
operational life of electrical motor brushes would have been desirable in all electrical
motors even those that also try to reduce brush noise or sound.
At the oral hearing appellants’ representative embellished upon the above
arguments and emphasized that Sugai teaches that the forces (f1 and f2) are applied in
both the direction of the commutator and in the direction of the side of the holder to
Appeal No. 2003-0025
Application No. 09/019,871
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prevent brush sound. Appellants’ representative further argued that the teaching of
Poet merely teaches the use of a constant force to the commutator without regard to
the force on the side of the brush housing and that the combination would not apply the
side force to reduce the brush sound. While we would tend to agree that the disclosure
of Poet does not disclose any concern for a lateral force being applied to force the side
of the brush to contact the holder, we note that in Figure 3, element Fx has both
longitudinal and lateral components which make up the force applied to the brush due
the angled portion which the biasing spring contacts. Therefore, there would have been
both longitudinal and lateral components of the forces in both Sugai and Poet. Hence,
we do not find appellants’ argument, that the examiner has merely picked from Poet the
use of a constant force and translated that teaching into use in the system of Sugai in
hindsight, persuasive. Appellants’ representative at oral hearing argued that the
teaching of a constant longitudinal component in Poet would have been a teaching
away from the combination with Sugai since Sugai is concerned with reducing the brush
noise/sound by the application of a lateral force to maintain the side of the brush in
contact with the holder. We disagree with appellants as discussed above since we find
that both Sugai and Poet teach both longitudinal and lateral components of the forces.
Appellants argue that the two references solve different problems and that
nowhere does Sugai suggest that he needs a different type of spring for applying a
constant pressure. (See brief at page 5.) While we agree with appellants that the two
Appeal No. 2003-0025
Application No. 09/019,871
8
references solve different problems, we do not find that this means that the examiner
relied upon impermissible hindsight. Therefore, this argument is not persuasive.
Appellants argue that the longitudinal axis is the lengthwise axis on the brush
and not the widthwise or lateral axis which the force (f1) is applied upon. (See reply
brief at page 2.) We disagree with appellants and find that Fig. 1(c) of Sugai clearly
teaches that the force (f1) acts along the axis towards the commutator 23. Therefore,
this argument is not persuasive. Appellants again emphasize the individual teachings
of the two references and conclude that there is no motivation to combine these
teachings. (See reply brief at page 2.) We disagree with appellants as discussed
above. Therefore, we will sustain the rejection of independent claim 1 and its
dependent claims 5-8 and 20 which appellants elected to group therewith.
With respect to independent claim 9, the examiner additionally relies upon the
teachings of Sekyra to teach the use of a unitary stop in the brush. (See answer at
pages 5-7.) Appellants argue that claim 9 requires that the spring moves on the angled
surface as the brush wears and there is a unitary stop. (See brief at page 6.)
Additionally, appellants argue that the examiner’s rejection is based upon hindsight
since the examiner has not provided a logical nexus as to the combination of the three
references. (See brief at page 6.) The examiner essentially repeats the motivation for
the combination as discussed with respect to independent claim 1. As discussed
above, we found a convincing motivation to combine the teachings of Sugai and Poet.
Appeal No. 2003-0025
Application No. 09/019,871
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Additionally, we find that the examiner’s reliance upon the teachings of Sekyra to teach
and suggest the use of a unitary stop for the brush would have been obvious to those
skilled in the art since the stop prevents the brush from advancing further than desired.
Therefore, we find a motivation to combine the three references. Appellants argue that
the examiner’s failure to provide a common strand in the three references further
indicates the use of impermissible hindsight. (See brief at page 6.) We disagree with
appellants as discussed above. Therefore, we will sustain the rejection of independent
claim 9 and its dependent claims 11, 12, 17, and 18 which appellants elected to group
therewith.
With respect to independent claim 19, appellants again argue that the examiner
has failed to show a logical nexus and that there is no logical connection that the
constant force in Poet would be used for in Sugai alone of in combination with Cousins.
(See brief at pages 6-7.) As discussed above, we disagree with appellants. Appellants
argue that there is no need for a constant force in Sugai as suggested by the examiner.
As discussed above, we find sufficient motivation for optimizing the brush life in the
system of Sugai as taught and suggested by Poet and as discussed above. Therefore,
we will sustain the rejection of independent claim 19.
CONCLUSION
To summarize, the decision of the examiner to reject claims 1, 5-9, 11, 12, and
17-20 under 35 U.S.C. § 103 is affirmed.
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Application No. 09/019,871
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No time period for taking any subsequent action in connection with this appeal
may be extended under 37 CFR § 1.136(a).
AFFIRMED
JOSEPH F. RUGGIERO )
Administrative Patent Judge )
)
)
)
) BOARD OF PATENT
JOSEPH L. DIXON ) APPEALS
Administrative Patent Judge ) AND
) INTERFERENCES
)
)
)
MAHSHID D. SAADAT )
Administrative Patent Judge )
JD/RWK
Appeal No. 2003-0025
Application No. 09/019,871
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