Ex Parte Persson et al

Board of Patent Appeals and Interferences

Apr 5, 2010

10908265 (B.P.A.I. Apr. 5, 2010)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________________

Ex parte PER PERSSON, BO SVENSSON and CHRISTER ALM
____________________

Appeal 2009-007459
Application 10/908,265
Technology Center 3700
____________________

Decided: April 5, 2010
____________________

Before LINDA E. HORNER, KEN B. BARRETT, and
FRED A. SILVERBERG, Administrative Patent Judges.

SILVERBERG, Administrative Patent Judge.

DECISION ON APPEAL

STATEMENT OF THE CASE
Per Persson et al. (Appellants) seek our review under 35 U.S.C. § 134
of the final rejection of claims 1-11, which are all of the pending claims. We
have jurisdiction under 35 U.S.C. § 6(b) (2006).

Appeal 2009-007459
Application 10/908,265

2
SUMMARY OF DECISION
We AFFIRM.

THE INVENTION
Appellants’ claimed invention is directed to regenerating a particle
filter arranged in thermal proximity to a catalyst unit in an exhaust duct of an
internal combustion engine (Spec. 1: [Para 2]).
Claim 1, reproduced below, is representative of the subject matter on
appeal.
1. A method for regenerating a particle filter
(15) arranged in thermal proximity to a catalyst
unit (16) in an exhaust duct (10) connected to an
internal combustion engine (2), said particle filter
being located downstream of an adjustable exhaust
pressure regulator (20) for regulating an exhaust
flow through the exhaust duct, said method
comprising:
establishing by means of a control unit (24)
that the internal combustion engine is being driven
at low engine load;
activating the exhaust pressure regulator
(20) with a predetermined regulating pressure; and
supplying fuel to the exhaust duct (10) by
means of an injection unit, the catalyst unit (16)
being exposed to said fuel, which is oxidized, and
the particle filter (15) being heated to a
temperature at which soot particles are converted
into carbon dioxide in reaction with oxygen
contained in the exhaust flow.

Appeal 2009-007459
Application 10/908,265

3
THE REJECTIONS
The Examiner relies upon the following as evidence of
unpatentability:
Terada US 6,758,037 B2 Jul. 6, 2004
Minami US 6,865,882 B2 Mar. 15, 2005

The following rejections1 by the Examiner are before us for review:
1. Claims 1-9 and 11 are rejected under 35 U.S.C. § 103(a) as being
unpatentable over Minami in view of Terada.
2. Claim 10 is rejected under 35 U.S.C. § 103(a) as being unpatentable
over Minami in view of Terada, and further in view of Applicants’
Admitted Prior Art2.

ISSUES
The issues before us are: (1) whether the Examiner erred in finding
that Minami describes “a particle filter in thermal proximity to a catalyst
unit,” as called for in claim 1 (Reply Br. 2; App. Br. 10); (2) whether the
Examiner erred in finding that Minami describes “heating the particulate
filter,” as called for in claim 1 (App. Br. 6); (3) whether the Examiner erred
in finding that Minami describes introducing unburned fuel to the exhaust,
as called for in claim 1 (App. Br. 8); and (4) whether the Examiner’s

1 In a communication mailed February 10, 2009, the rejection of claims 1-3,
6-8 and 11 under 35 U.S.C. § 102(e) as being anticipated by Sato and as set
forth in the Final Rejection mailed September 17, 2007 (Final Rejection 3),
has been withdrawn.
2The Examiner denoted Appellants failure to challenge the Examiner’s
taking of official notice as Applicants’ Admitted Prior Art (Ans. 6).
Appeal 2009-007459
Application 10/908,265

4
proposed combination of Minami and Terada impermissibly destroys the
teachings of Minami (App. Br. 11).

FINDINGS OF FACT
We find that the following enumerated findings are supported by at
least a preponderance of the evidence. Ethicon, Inc. v. Quigg, 849 F.2d
1422, 1427 (Fed. Cir. 1988) (explaining the general evidentiary standard for
proceedings before the Office).
1. Appellants’ Specification describes “[i]n the present context,
thermal proximity shall be taken to mean that the reaction which
takes place in the oxidation catalyst is capable of heating the
particle filter.” (emphasis added) (Spec. 4: [Para 17]).
2. Minami describes that diesel particulate filters (DPF) are
regenerated by burning particulate matter trapped on the DPF (col.
1, ll. 11-24).
3. Minami describes in the Description Of The Related Art that:
[i]n the exhaust pipe 7 on the downstream side of the
exhaust gas turbine 81, there are arranged a
continuous regeneration type diesel particulate filter
12 having an oxidizing catalyst 121 and a DPF 122 in
this order from the upstream side, and a NOx catalyst
14 . . . Thus, the continuous regeneration type DPF 12
is constituted by at least the above-mentioned
oxidizing catalyst 121 and the DPF 122, where the
oxidizing catalyst 121 oxidizes NO in the exhaust gas
Appeal 2009-007459
Application 10/908,265

5
into NO2 and the trapped PMs are burned with NO2
that flows into the DPF 122 arranged on the
downstream side of the oxidizing catalyst 121.
(col. 2, ll. 27-61 and figs. 13 and 10).
4. Terada describes in the Background Of The Invention that:
[a]ccordingly, the particulate filter must be heated up
with use of some heat-up means to burn the deposited
soot compulsively (for compulsive regeneration) in a
timely manner. As is generally known, the
compulsive regeneration is achieved by injecting a
fuel (for so-called post-injection) in the expansion
stroke of the engine.
(col. 1, ll. 30-35).
5. Terada describes that:
[i]f the exhaust gas temperature is somewhat lower
than the peak value of the active temperature, control
(continuous regeneration support process) is carried
out to raise the temperature of the oxidizing catalyst
43 to a value near the peak value, in order to enhance
the conversion factor of the catalyst 43. The
continuous regeneration support process is achieved
by, for example, working the shutter 42 to some
extent to increase the exhaust gas temperature.
(col. 4, ll. 25-32).
6. Terada describes that:
[i]n this compulsive regeneration, the post-injection is
carried out to heat up the filter 44. When this post-
injection is achieved, the fuel injected into the
combustion-chamber 21 in the expansion or exhaust
stroke of the engine reaches the oxidizing catalyst 43.

3 Minami describes that “[i]n the embodiment illustrated in FIG. 1, the same
constituent members as those of the conventional device for purifying
exhaust gas shown in FIG. 10 are denoted by the same reference numerals
but are not described here again.” (col. 5, ll. 42-46).
Appeal 2009-007459
Application 10/908,265

6
This fuel (HC) is oxidized by means of the catalyst
43. The filter 44 is heated up by heat release that is
attributable to the oxidation by means of the catalyst
43, and soot is oxidized (burned) directly by O2 on the
filter 44 in a temperature range (e.g., 500° C. to 550°
C. or more) higher than the range for continuous
operation.
. . . .
Thus, when the post-injection is carried out, the
component (HC) to be oxidized by the oxidizing
catalyst is supplied to the catalyst. The filter 44 is
heated up with heat of oxidation that is produced
when this component is oxidized by means of the
catalyst, and the soot on the filter 44 is burned and
removed, whereupon the filter 44 is regenerated.
(col. 5, ll. 35-60).
7. Terada describes using both continuous regeneration and
compulsive regeneration to regenerate a DPF. In continuous
regeneration, an oxidizing catalyst 43 oxidizes the NO in the
exhaust gas (col. 4, ll. 8-18 and 30-32) (see also Fact 5) and in
compulsive regeneration, post-injection is carried out to heat up the
filter 44 (see also Fact 6).
8. Additional findings as necessary appear in the Analysis portion of
this opinion.

PRINCIPLES OF LAW
Obviousness
In KSR, the Supreme Court held that “if a technique has been used to
improve one device, and a person of ordinary skill in the art would recognize
that it would improve similar devices in the same way, using the technique is
Appeal 2009-007459
Application 10/908,265

7
obvious unless its actual application is beyond his or her skill.” KSR Int'l
Co. v. Teleflex Inc., 550 U.S. 398, 417 (2007).

Claim Construction
When construing claim terminology in the United States Patent and
Trademark Office, claims are to be given their broadest reasonable
interpretation consistent with the specification, reading claim language in
light of the specification as it would be interpreted by one of ordinary skill in
the art. In re Am. Acad. of Sci. Tech. Ctr., 367 F.3d 1359, 1364 (Fed. Cir.
2004).

ANALYSIS
Appellants argue claims 1-5 as a first group and claims 6-9 and 11 as
a second group, with the same arguments being applicable to both groups.
(App. Br. 5). As such, we select claim 1 as representative of the first group,
and claims 2-5 will stand or fall with claim 1. Since Appellants do not
present any arguments for the patentability of the claims of second group,
claims 6-9 and 11, separate from the first group, claims 6-9 and 11 will stand
or fall with claim 1. 37 C.F.R. § 41.37(c)(1)(vii) (2009).
Appellants contend that Minami does not describe (1) “a particle filter
in thermal proximity to a catalyst unit” (Reply Br. 2; App. Br. 10) and (2)
“heating the particulate filter” (App. Br. 6), as called for in claim 1.
The Examiner found that Minami describes a particulate filter 122
arranged in thermal proximity to a catalyst unit 121 (Ans. 3, 8) and that the
particulate filter is heated (Ans. 4, 7).
Appeal 2009-007459
Application 10/908,265

8
Appellants’ Specification describes that the term thermal proximity
means that the reaction which takes place in the oxidation catalyst is
capable of heating the particulate filter (Fact 1).
Minami describes that the oxidizing catalyst 121 oxidizes NO in the
exhaust gas into NO2 that flows into the DPF 122 arranged on the
downstream side of the oxidizing catalyst 121 (Fact 3).
The Examiner found that the particle filter of Minami is in thermal
proximity to the catalyst unit because the oxidizing of the NO in the exhaust
gas stream at the catalyst unit causes a chemical reaction that generates heat,
the generated heat raises the temperature of the exhaust gas and the heated
exhaust gas flows through and heats the (DPF) filter. (Ans. 7, 8-9).
Appellants do not contest this finding. Reply Br. passim. Rather,
Appellants argue that Minami raises the exhaust gas by regulating the
exhaust gas recirculation valve, the air intake shutter, and the exhaust shutter
to bring the exhaust gas temperature into the active temperature region for
the catalyst. (Reply Br. 2). We do not disagree with this reading of Minami.
Appellants’ argument, however, fails to address the Examiner’s finding that
Minami additionally heats the exhaust gas by virtue of the heat generated
from the oxidation reaction in the catalyst unit.
We conclude that Appellants’ definition of thermal proximity (Fact 1)
does not require that the heat generated by the chemical reaction directly
heat DPF, as Appellants would have us understand. In Minami, since the
heat generated by the chemical reaction generates the heat that raises the
exhaust gas temperature that ultimately raises the DPF temperature, that is,
heats the DPF, we find that the heat generated by the chemical reaction heats
Appeal 2009-007459
Application 10/908,265

9
the DPF. Therefore, we find that Minami’s DPF 122 is in thermal proximity
to the catalyst 121. See In re Am. Acad. of Sci. Tech. Ctr., 367 F.3d at 1364.
Appellants contend that Minami does not describe introducing
unburned fuel in to the exhaust, as called for in claim 1 (App. Br. 8).
Claim 1 calls for, inter alia, supplying unburned fuel to the exhaust
duct.
The Examiner, citing to column 2, lines 37-39 and column 8, lines 46-
49, found that Minami describes adding unburned fuel to the exhaust duct
(Ans. 3, 4).
We find that the Examiner’s finding is incorrect, as Minami is silent
as to unburned fuel being added to the exhaust duct.
Appellants further contend that the Examiner’s proposed combination
of Minami and Terada impermissibly destroys the teachings of Minami
(App. Br. 11).
The Examiner found (1) that Minami does not describe performing
post fuel injection (post injection) and (2) that Terada describes post fuel
injection (post injection) to supply unburned fuel to a catalyst unit to raise
the temperature of the exhaust gas (Ans. 4). The Examiner concluded that it
would have been obvious to utilize the post fuel injection (post injection)
taught by Terada in Minami (Ans. 4).
Claim 1 calls for, inter alia, supplying fuel to the exhaust duct by
means of an injection unit to heat the particulate filter.
Minami describes using continuous regeneration to regenerate the
DPF (Fact 3, see also Fact 2). Terada describes using both continuous
regeneration and compulsive regeneration to regenerate a DPF (Fact 7, see
also Facts 5, 6), wherein the compulsive regeneration includes injecting a
Appeal 2009-007459
Application 10/908,265

10
fuel (for so-called post injection) in the expansion stroke of the engine (Fact
4).
Since Terada describes that both continuous regeneration and
compulsive regeneration can be used together to regenerate a DPF, we see
no reason why compulsive regeneration of a DPF could not also be used
with the continuous regeneration of the DPF taught by Minami.
Appellants argue that “the proffered combination of references may
actually be counterproductive to the point of being destructive.” (App. Br.
11). In particular, Appellants tentatively contend that if adding unburned
fuel into Minami’s exhaust would raise the temperature of the exhaust gas,
“then temperature may be increased so much more that the catalyst no
longer functions properly or is even destroyed.” Id. Appellants have not
stated unequivocally that adding unburned fuel to Minami’s exhaust would
render the catalyst inoperable, nor have they supplied any evidence to
demonstrate this fact. An attorney’s arguments in a brief cannot take the
place of evidence. In re Pearson, 494 F.2d 1399, 1405 (CCPA 1974).
We conclude that it would have been obvious to a person having
ordinary skill in the art to combine the teachings of Minami and Terada by
utilizing in Minami, compulsive regeneration of the DPF, that is, injecting a
fuel (for so-called post injection) as taught by Terada. Therefore, we
determine that the Examiner did not rely on impermissible hindsight, as
Appellant urges (App. Br. 12), but rather relied on the knowledge of those
skilled in the art at the time of the invention.
We find that utilizing compulsive regeneration of a DPF along with
continuous regeneration of the DPF could have been reasonably predicted to
Appeal 2009-007459
Application 10/908,265

11
yield the result of more effective regeneration of the DPF. See KSR, 550
U.S. at 417.
Therefore, we sustain the rejection of claim 1, and claims 2-9 and
11, which stand or fall with claim 1. Likewise, we sustain the rejection of
claim 10, as Appellants do not present any separate arguments for the
patentability of claim 10 apart from the arguments presented for
independent claim 1. (App. Br. 5, 6 fn2).

CONCLUSIONS
The Examiner has not erred in finding that Minami describes “a
particle filter in thermal proximity to a catalyst unit,” as called for in claim
1.
The Examiner has not erred in finding that Minami describes “heating
the particulate filter,” as called for in claim 1.
The Examiner has erred in finding that Minami describes introducing
unburned fuel to the exhaust, as called for in claim 1.
The Examiner’s proposed combination of Minami and Terada does
not impermissibly destroy the teachings of Minami.

DECISION
The decision of the Examiner to reject claims 1-11 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) (2007).

AFFIRMED

Klh
Appeal 2009-007459
Application 10/908,265

12

NOVAK DRUCE AND QUIGG LLP (VOLVO)
1000 LOUISIANA STREET
FIFTY-THIRD FLOOR
HOUSTON, TX 77002