Ex Parte Nentrup

Board of Patent Appeals and Interferences

Dec 27, 2010

10965512 - (D) (B.P.A.I. Dec. 27, 2010)

UNITED STATES PATENT AND TRADEMARK OFFICE
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
10/965,512 10/14/2004 Trent Lee Nentrup 67341-2161; 04ARM0203 4221
26096 7590 12/28/2010
CARLSON, GASKEY & OLDS, P.C.
400 WEST MAPLE ROAD
SUITE 350
BIRMINGHAM, MI 48009
EXAMINER
PHILLIPS, FORREST M
ART UNIT PAPER NUMBER
2832
MAIL DATE DELIVERY MODE
12/28/2010 PAPER
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
PTOL-90A (Rev. 04/07)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________________

Ex parte TRENT LEE NENTRUP
____________________

Appeal 2009-007250
Application 10/965,5121
Technology Center 2800

____________________

Before MARC S. HOFF, CARLA M. KRIVAK,
and CARL W. WHITEHEAD, JR., Administrative Patent Judges.

HOFF, Administrative Patent Judge.

DECISION ON APPEAL2

1 The real party in interest is ET US Holdings LLC.
2 The two-month time period for filing an appeal or commencing a civil
action, as recited in 37 C.F.R. § 1.304, or filing a request for rehearing, as
recited in 37 C.F.R. § 41.52, begins to run from the “MAIL DATE” (paper
delivery mode) or the “NOTIFICATION DATE” (electronic delivery mode)
shown on the PTOL-90A cover letter attached to this decision.
Appeal 2009-007250
Application 10/965,512

STATEMENT OF THE CASE
Appellant appeals under 35 U.S.C. § 134(a) from a Final Rejection of
claims 1-4, 7-13, and 19-20. We have jurisdiction under 35 U.S.C. § 6(b).
We affirm.
Appellant’s invention relates to an exhaust silencer that includes an
upper shell and a lower shell coupled to define an internal cavity. Acoustic
damping material is positioned within the internal cavity to reduce radiated
and transmitted noise. A plurality of retention members compresses the
acoustic damping material against an inner surface of the upper shell. Since
the acoustic damping material is only located in the upper shell, it is not
affected by condensate that collects in the lower shell. (Abstract).
Claim 1 is exemplary:
1. An exhaust silencer comprising:
an upper shell;
a lower shell attached to said upper shell to define an internal cavity;
and
acoustic damping material held within said internal cavity against said
upper shell wherein said acoustic damping material comprises a mat that is
compressed against said upper shell.

The prior art relied upon by the Examiner in rejecting the claims on
appeal is:
Damiron US 3,823,796 Jul. 16, 1974
Harwood US 4,736,817 Apr. 12, 1988
Angelo US 6,354,398 B1 Mar. 12, 2002

Claims 1-4, 7-13, and 19-20 stand rejected under 35 U.S.C. § 103(a)
as being unpatentable over Harwood in view of Damiron and Angelo.

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ISSUES
Appellant contends that “Harwood does not disclose only disposing
acoustic damping material between plates 206 and 202” within the upper
shell of the muffler (App. Br. 4). Appellant asserts that Harwood suggests
damping material could also be disposed between plates 204 and 208 of the
lower shell of the muffler (App. Br. 4, Reply Br. 2).
Regarding the proposed combination, Appellant asserts that since the
mufflers of Damiron and Angelo use an annular arrangement of packing
material, the modification of the muffler of Harwood would result in a
configuration where the compressed material would surround the inlet
component in both the upper and lower shells of the muffler (App. Br. 4-6;
Reply Br. 2-3). Appellant argues further that the porous wall structure of
Damiron is not a functional equivalent of the non-woven mat disclosed in
Angelo (App. Br. 5; Reply Br. 3-4).
Appellant argues further that since Harwood already includes a
configuration that absorbs pressure waves, there would be no reason to
modify Harwood to include a feature that is already present (App. Br. 4). As
a result, Appellant contends that the Examiner has relied on impermissible
hindsight (App. Br. 4).
With reference to an internal cavity, Appellant contends that since the
insulating material of Harwood completely fills the space between plates
202 and 206, Harwood does not disclose a second surface of the insulating
material facing an internal cavity (App. Br. 7). In addition, Appellant
contends that the mat disclosed in Angelo is not compressed against an
upper shell but rather fills an annular space (App. Br. 6). Similarly,
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Application 10/965,512

Appellant asserts that the compressed material of Damiron is not
compressed against the side wall of the muffler (Reply Br. 2).
Finally, Appellant contends that none of the references disclose the
use of retention members (App. Br. 9). Appellant asserts that the
substitution of internal plate 202 with a plurality of retention plates to
compress the acoustic damping material against the inner surface of upper
shell 206 would render the muffler disclosed in Harwood unsatisfactory for
its intended purpose since the stamped formed internal plate 202 provides
the feature of high frequency tuning chambers and low frequency resonating
chambers (Reply Br. 6-7).
Appellant’s contentions present us with the following four issues:
1. Do the references disclose a muffler that includes an “acoustic
damping material held within said internal cavity against said upper shell”?
2. Do the references disclose an internal cavity defined by an upper
and lower shell?
3. Do the references disclose or suggest a muffler that includes “at
least one compression member in engagement with said second surface to
generate a retaining force for holding said mat against said upper shell”?
4. Would the proposed modification of the prior art render the prior
art invention unsatisfactory for its intended purpose?

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Application 10/965,512

FINDINGS OF FACT
The following Findings of Fact (FF) are shown by a preponderance of
the evidence.
Harwood
1. Harwood discloses that muffler 200 is assembled by joining the
internal plates 202 and 204 together at selected locations and joining
external shells 206 and 208 around the structure formed by internal plates
202 and 204. “An insulating material 260 may be disposed in at least one
half of the expansion chamber, as shown” (Figs. 6 and 7; col. 10, ll. 22-28).
2. Harwood discloses that muffler 200 includes stamp formed
internal plates 202 and 204 and stamp formed external plates 206 and 208.
The internal plates 202 and 204 are stamp formed to define inlet channels
210 and 211. Internal plate 202 further includes outlet channel 216 having
an array of perforations 218. “Channels 220 and 222 are stamp formed in
internal plate 202 to intersect outlet channel 216 in two locations on opposite
ends of the array of perforations 218” (Fig. 6; col. 9, ll. 16-30 and 39-51).
3. Harwood discloses that the muffler, as a result of the structure
formed from the internal plates 202 and 204, enables the effective
construction of two tuning tubes leading into a single low frequency
resonating chamber. Specifically, with respect to internal plate 202, the
primary flow of exhaust gases will enter the expansion chamber through
arrays of perforations 214 in inlet channel 210. “These exhaust gases will
circulate through the expansion chamber defined by expansion chamber
shells 240 and then into the apertures 226 . . . of the return tube formed by”
channel 224. The gases will continue to flow through the outlet formed by
channel 216. “In traveling to the outlet, the exhaust gases will travel through
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Application 10/965,512

the high frequency tuning chambers defined by channels 250,” 220, and 222.
The portion of the inlet between perforation arrays 214 and the apertures 212
will function as a tuning tube. Similarly, the stamp formed channel 228
leading to the aperture 230 will function as a tuning tube. (Col. 10, ll. 22-
48).
Damiron
4. Damiron discloses a muffler for an internal combustion engine
that includes a casing 2 fitted with a gas inlet conduit 1 and a gas outlet
conduit. The gas outlet conduit includes a resonant cavity and an exhaust
pipe 12 connecting the resonant cavity to the atmosphere. The resonant
cavity includes a first resonant chamber 7, a diaphragm 4, a piston 8 and a
second resonant chamber 10. The exhaust gas flowing between an end 3 of
gas conduit 1 and the diaphragm 4 cause residual return waves to be formed
which are transverse, spherical waves. A return-flow path for the flow of
gases includes porous walls 13 containing slightly compressed metal fibers
which form a resilient means for absorbing the waves when contacting the
gases. (Fig. 1; col. 1, ll. 33-42; col. 1, l. 61-col. 2, l. 1; col. 2, ll. 35-59).
Angelo
5. Angelo discloses a muffler having an annular volume 58
defined between inner wall 57 and outer wall 3. “[A]nnular volume 58 is
filled with an absorptive filling such as stuffing, padding, or packing 59.”
Packing 59 may comprise a non-woven mat. Backing 61 attaches to non-
woven fibers 62 to form packing 59. When packing 59 is installed within
annular volume 58, “fibers 62 are adjacent to the outer wall 51, while
backing 61 is adjacent to inner wall 57.” (Figs. 2 and 2A; col. 12, ll. 24-27;
40-55).
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Appeal 2009-007250
Application 10/965,512

PRINCIPLE OF LAW
On the issue of obviousness, the Supreme Court has stated that “the
obviousness analysis cannot be confined by a formalistic conception of the
words teaching, suggestion, and motivation.” KSR Int’l Co. v. Teleflex Inc.,
550 U.S. 398, 419 (2007). Further, the Court stated “[t]he combination of
familiar elements according to known methods is likely to be obvious when
it does no more than yield predictable results.” Id. at 416.

ANALYSIS
Claims 1 and 2
Claim 1 recites “acoustic damping material held within said internal
cavity against said upper shell.” Similarly, claim 2 recites “said mat is
compressed against an inner surface of said upper shell.”
Regarding the first issue, we do not consider Appellant’s arguments to
be persuasive to show Examiner error. Harwood discloses a muffler 200,
having external plates 206 and 208 that form the upper and lower shell (FF
1). As shown in Figure 7 of Harwood, insulating material 260 is held in
place within the internal cavity formed between internal plate 202 and upper
external plate 206 (FF 1). Damiron discloses a muffler that includes a
material made of compressed metal fibers that form a resilient means of
absorbing sound waves when gases contact it (FF 4). Angelo discloses a
muffler that includes an absorptive filling such as packing 59 that comprises
a non-woven mat (FF 5). Therefore, a muffler disclosed in Harwood as
modified by Damiron would include an acoustic damping material, such as a
non-woven mat made of compressed metal fibers (FF 1, 4, and 5).
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Although Harwood discloses that the insulating material may be
disposed in “at least one half of the expansion chamber,” Harwood clearly
shows in the embodiment of Figure 7 that the insulating material is solely
located within the internal cavity formed by upper external plate 206 and
internal plate 202 (FF 1). Therefore, modifying Harwood would include
modification of the acoustic damping material in the upper shell and not
adding damping material to the lower shell (FF 1).
Since the claim language does not preclude the material from being
disposed in more than one half, Appellant’s argument that Harwood must
limit the use of the insulating material to only the upper shell is not
commensurate with the scope of the claims (App. Br. 5). Claims are
interpreted in light of the specification; limitations from the specification are
not read into the claims. In re Van Geuns. 988 F.2d 1181, 1184 (Fed. Cir.
1993).
The combination of familiar elements, such as the acoustic damping
materials of Damiron and Angelo within the muffler of Harwood, according
to known methods is likely to be obvious since it does no more than yield
the predictable result of absorbing pressure waves of exhaust gases within
the muffler. KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 416 (2007).
Therefore, we find that the Examiner has established the prima facie
obviousness of the claims, because the combination of Harwood, Damiron,
and Angelo discloses an exhaust silencer that includes “acoustic damping
material held within said internal cavity against said upper shell wherein said
acoustic damping material comprises a mat that is compressed against said
upper shell.” As a result, we sustain the Examiner’s § 103 rejection of
independent claim 1 and that of dependent claim 2.
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Claims 3, 7, and 19
Claim 3 requires that “said mat has a first surface substantially
engaging said inner surface and a second surface facing said internal cavity.”
Claims 7 and 19 recite a similar claim limitation.
With reference to the second issue regarding the formation of an
internal cavity, we do not consider Appellant’s arguments to be persuasive
to show Examiner error. Harwood discloses that the stamped internal plate
202 serves to hold the insulating material 260 against the upper shell formed
by external plate 206 (FF 1). The muffler disclosed in Harwood as modified
by Damiron and Angelo includes replacing insulation material 260 with a
non-woven mat made of compressed metal fibers (FF 1, 4, and 5).
Therefore, the first surface of the non-woven mat would be in direct contact
with the interior surface of the upper shell 206 and the second surface of the
non-woven mat would be the upper boundary for the internal cavity formed
between the non-woven mat and internal plate 202 (FF 1 and 5). Further,
the mat would still need to be compressed against the interior surface of the
upper shell 206 or held in place by a fastening or compression means as
disclosed in Harwood (FF 1).
Therefore, we find that the Examiner has established the prima facie
obviousness of the claims, because the combination of Harwood, Damiron
and Angelo discloses an exhaust silencer that includes “said mat has a first
surface substantially engaging said inner surface and a second surface facing
said internal cavity.” As a result, we sustain the Examiner’s § 103 rejection
of claims 3, 7, and 19.
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Claims 4, 11, 12, and 20
Claim 4 recites “including at least one compression member in
engagement with said second surface to generate a retaining force for
holding said mat against said upper shell.” Similarly, independent claim 11
recites “a plurality of retention members compressing said acoustic damping
material against an inner surface of the upper shell.” Claims 12 and 20
depend from claim 11.
Regarding the issue of disclosure of a compression member or a
plurality of retention members, we do not consider Appellant’s arguments to
be persuasive to show Examiner error. Harwood discloses that the stamped
internal plate 202 has two functions (FF 1-3). The first function of internal
plate 202 is similar to that of a retention or compression member wherein
stamped internal plate 202 serves as a “retaining force for holding” the
insulating material 260 against the upper shell formed by external plate 206
(FF 1).
The second function of internal plate 202 is to enable effective
construction within the muffler of two tuning tubes leading into a single low
frequency resonating chamber (FF 2 and 3). These two tuning tubes are
made by the channels formed by the stamped impressions of internal plates
202 and 204 (FF 2 and 3). Specifically, internal plate 202 forms inlet
channel 210, channels 220, 222, tuning channel 228, return channel 224 and
outlet channel 216 for directing the exhaust gas (FF 2 and 3).
Although Harwood discloses that the primary function of stamped
internal plates 202 and 204 of the muffler is for enabling effective
construction of two tuning tubes leading into a single low frequency
resonating chamber, we find that this disclosure does not preclude the
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internal plate 202 from functioning as a “retaining force for holding”
insulating material similar to that of the claimed retention or compression
members (FF 1 and 3). Although one cannot merely substitute a plurality of
retention members for the internal plate 202 and retain the function of the
tuning tubes, Harwood clearly discloses the feature of compressing the
acoustic damping material against the upper shell using internal plate 202 as
a “retaining force” (FF 1).
Therefore, we find that the Examiner has established the prima facie
obviousness of the claims, because the combination of Harwood, Damiron,
and Angelo discloses an exhaust silencer that includes “acoustic damping
material held within said internal cavity against said upper shell wherein said
acoustic damping material comprises a mat that is compressed against said
upper shell.” As a result, we sustain the Examiner’s § 103 rejection of
claims 4, 11, 12, and 20.
Claims 8-10, 13, and 19
Claim 8 recites “wherein said mat is only located in said upper shell.”
Similarly, claim 13 recites “acoustic damping material is only located in said
upper shell.” Claim 19 recites “wherein said mat is pressed only against an
inner surface of said upper shell such that said internal cavity extends into
both said upper and lower shells to define an exhaust flow path.”
Similar to the first issue regarding the location of the acoustic
damping material within the internal cavity of the upper shell, we do not
consider Appellant’s arguments to be persuasive to show Examiner error.
As noted supra, Harwood clearly discloses that insulating material 260 is
held in place within the internal cavity formed between internal plate 202
and upper external plate 206 or upper shell (FF 1).
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Therefore, we find that the Examiner has established the prima facie
obviousness of the claims, because the combination of Harwood, Damiron,
and Angelo discloses an exhaust silencer that includes “acoustic damping
material held within said internal cavity against said upper shell wherein said
acoustic damping material comprises a mat that is compressed against said
upper shell.” As a result, we sustain the Examiner’s § 103 rejection of
claims 8, 13, and 19 and that of dependent claims 9 and 10.

CONCLUSIONS
The references disclose a muffler that includes an “acoustic damping
material held within said internal cavity against said upper shell.”
The references disclose an internal cavity defined by an upper and a
lower shell.
The references disclose a muffler that includes “at least one
compression member in engagement with said second surface to generate a
retaining force for holding said mat against said upper shell.”
The proposed modification of the prior art would not render the prior
art invention unsatisfactory for its intended purpose.

ORDER
The Examiner’s rejection of claims 1-4, 7-13, and 19-20 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).

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Appeal 2009-007250
Application 10/965,512

AFFIRMED

ELD

CARLSON, GASKEY & OLDS, P.C.
400 WEST MAPLE ROAD
SUITE 350
BIRMINGHAM, MI 48009

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