Ex parte Chang et al.

Board of Patent Appeals and Interferences

Jun 20, 2001

08382296 (B.P.A.I. Jun. 20, 2001)

1
The opinion in support of the decision being entered today was
not written for publication and not binding precedent of the
Board.
Paper No. 13
UNITED STATES PATENT AND TRADEMARK OFFICE
__________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
__________
Ex parte HSUEH-CHIA CHANG
and DAVID T. LEIGHTON
__________
Appeal No. 1998-1133
Application 08/382,296
___________
ON BRIEF
___________
Before WARREN, OWENS and LIEBERMAN, Administrative Patent
Judges.
OWENS, Administrative Patent Judge.
DECISION ON APPEAL
This is an appeal from the examiner’s final rejection of
claims 4, 7-11 and 14-22, which are all of the claims
remaining in the application.
THE INVENTION
The appellants’ claimed invention is directed toward a
system and method for treating exhaust gases of an internal
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Application 08/382,296

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combustion engine. Claims 21 and 22 are illustrative:
21. Exhaust gas treatment system for treating the
exhaust gases of an internal combustion engine comprising:
an exhaust pipe;
a catalytic converter having an inlet and an outlet
connected in said exhaust pipe for treating exhaust gases
passing through said exhaust pipe;
an igniter in said exhaust pipe having an inlet and an
outlet, the inlet of said catalytic converter being connected
to the outlet of said igniter, said igniter including catalyst
material for raising the temperature of the exhaust gases
passing through said igniter to a temperature sufficient to
ignite said
catalytic converter;
a bypass passage extending around said igniter to
communicate exhaust gases directly to said catalytic converter
bypassing said igniter;
a control valve in said exhaust pipe shiftable from a
first position in which a first portion of said exhaust gases
are directed through said bypass passage and a second portion
of the exhaust gases are directed through said igniter, said
first portion being greater than said second portion, to a
second position in which substantially all of the exhaust
gases are directed through said bypass passage; and
a controller responsive to the temperature within said
catalytic converter for shifting said control valve between
said first and second positions, said controller switching
said valve to said first position after engine start but
before ignition of said catalytic converter and to said second
position after ignition of said catalytic converter.
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Application 08/382,296

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22. Method of treating exhaust gases of an internal
combustion engine comprising the steps of passing a first
portion of said exhaust gases through an igniter containing a
catalyst material, passing a second portion of the exhaust
gases through a bypass passage bypassing said igniter, said
second portion being greater than said first portion,
permitting said catalyst within said igniter to increase the
temperature of the exhaust gases passing through the igniter,
passing the exhaust gases through a catalyst bed within a
catalytic converter after said first portion of the exhaust
gases has passed through the igniter and the temperature of
the exhaust gas has been raised to a temperature to ignite the
catalyst within the catalyst bed of the catalytic converter.
THE REFERENCES
Säufferer 3,440,817 Apr. 29,
1969
Rudy 5,010,051 Apr. 23,
1991
Dunne et al. (Dunne) 5,051,244 Sep. 24,
1991
Abe et al. (Abe) 5,296,198 Mar. 22,
1994
THE REJECTIONS
The claims stand rejected under 35 U.S.C. § 103 as
follows: claims 4, 7, 8, 14-19, 21 and 22 over Rudy in view of
Dunne and Säufferer, and claims 9-11 and 20 over these
references further in view of Abe.
OPINION
We reverse the rejection of claims 4, 7-11 and 21, and
affirm the rejection of claims 14-20 and 22.
Appeal No. 1998-1133
Application 08/382,296

Our discussion does not address Abe, which was applied1
to dependent claims to show an electrically actuated heater
upstream of a catalyst (answer, page 6).
4
The appellants state that the claims stand or fall in two
groups: 1) claims 4, 7-11 and 21, and 2) claims 14-20 and 22
(brief, page 5). We therefore limit our discussion to one
claim in each group, i.e., claims 21 and 22, which are the
only independent claims. See In re Ochiai, 71 F.3d 1565, 1566
n.2, 37 USPQ2d 1127, 1129 n.2 (Fed. Cir. 1995); 37 CFR
§ 1.192(c)(7)(1995).1
Rejection of claim 21
The appellants’ claim 21 requires a controller which is
capable of switching a control valve to a first position in
which a first portion of exhaust gases is directed through a
bypass around an igniter, and a smaller second portion of
exhaust gases is directed through the igniter, after engine
start-up but before ignition of a downstream catalytic
converter.
Rudy discloses upstream and downstream catalysts with no
bypass (abstract).
Dunne discloses a system wherein, during desorption of
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pollutants from an adsorbent bed, a major portion of exhaust
gases is bypassed around the adsorbent bed and a minor portion
of exhaust gases is passed through the adsorbent bed
(abstract). Immediately downstream of the adsorbent bed can
be positioned a catalyst bed whose major function is to
convert hydrocarbons and carbon monoxide to carbon dioxide and
water (abstract; col. 10, lines 1-14). The system is switched
to this condition in which a minor portion of the exhaust
gases is passed through the adsorbent bed and catalyst and the
remaining exhaust gases is bypassed around these components,
however, only after a downstream primary catalyst bed reaches
a selected temperature which typically is 350-400EC (abstract;
col. 6, lines 13-17). Dunne teaches that such a primary
catalyst works quite well after it has reached an operating
temperature of about 300EC (col. 1, lines 31-33; col. 5, lines
46-48), which indicates that Dunne’s system is capable of
switching to the above condition only after ignition of the
primary catalyst rather than beforehand as required by the
appellants’ claim 21.
Säufferer discloses a system wherein a bypass (5) around
a quick-warm-up catalytic unit (3) is closed during start-up
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of an engine, and opens increasingly as soon as the catalyst
in a downstream main catalytic unit (4) reaches its response
temperature (col. 1, lines 15-19; col. 2, lines 55-58 and 66-
70; col. 3, lines 66-71; col. 4, lines 18-23; col. 4, line 73
- col. 5, line 3). Thus, Säufferer’s system is capable of
bypassing the quick-warm-up catalytic unit only after the main
catalytic unit reaches its ignition temperature, not
beforehand as required by the appellants’ claim 21.
The examiner interprets “ignition” in view of the
appellants’ specification as being the condition at which the
exhaust gases about to enter the downstream catalytic unit are
at about 700EK (427EC) (answer, page 7). The examiner relies
(answer, page 7) upon statements in the appellants’
specification that the exhaust gases are heated such that they
are at a temperature of 700EK at the catalytic converter inlet
(page 4, lines 1-4; page 6, lines 20-25; page 7, lines 2-5).
The examiner argues that the catalytic converter response
temperatures disclosed by Dunne and Säufferer of,
respectively, 300EC (col. 1, lines 31-33) and 250-300EC (col.
3, lines 5-9), are below 700EK and that, therefore, Dunne and
Säufferer bypass the upstream catalytic unit at a temperature
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Application 08/382,296

The appellants’ argument is consistent with this2
interpretation (reply brief, pages 2-3).
7
below what the appellants consider to be the temperature
required for ignition (answer, page 8).
The appellants’ specification does not specifically
define “ignition”. According to the appellants’
specification, 700EK is the temperature at which an ordinary
catalytic converter will rapidly ignite at its leading edge
(page 2, lines 22-24). The specification indicates that poor
light off behavior can be obtained at 600EK (327EC) (page 1,
lines 26-28). When we give the term “ignition” its broadest
reasonable interpretation in view of the specification, see In
re Zletz, 893 F.2d 319, 321, 13 USPQ2d 1320, 1322 (Fed. Cir.
1989); In re Sneed, 710 F.2d 1544, 1548, 218 USPQ 385, 388
(Fed. Cir. 1983), we find that it refers to the temperature at
which the leading edge of a catalytic converter lights off. 2
As discussed above, contrary to the requirement of the
appellants’ claim 21, both Dunne and Säufferer disclose
systems which require this temperature before the above-
discussed bypass condition is reached.
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Accordingly, we conclude that the examiner has not
carried the burden of establishing a prima facie case of
obviousness of the system recited in claim 21. We therefore
reverse the rejection of this claim and the claims which
depend therefrom.
Rejection of claim 22
Dunne discloses a method for treating exhaust gases of an
engine which can be an internal combustion engine (col. 4,
lines 34-39). At a point in the method where hydrocarbons are
being desorbed from an adsorbent bed which is followed by a
catalytic bed (which corresponds to the appellants’ igniter),
a minor portion of the exhaust gases is passed through the
adsorbent and catalytic bed, and a major portion of the
exhaust gases is bypassed around the adsorbent and catalytic
bed (abstract; col. 10, lines 1-14). The catalytic bed
converts hydrocarbons and carbon monoxide to carbon dioxide
and water (col. 10, lines 7-9). These combustion reactions
necessarily increase the temperature of the exhaust gases
passing through the catalytic bed. The exhaust gases from the
catalytic bed are passed to a catalytic converter after the
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temperature of the exhaust gases has been raised to a
temperature to ignite the catalyst within the catalyst bed of
the catalytic converter (abstract; col. 1, lines 31-33; col.
6, lines 14-18).
Säufferer discloses a method for treating exhaust gases
of an internal combustion engine (col. 1, lines 23-25). When
the engine is started, a bypass (5) around a quick-warm-up
catalytic unit (which corresponds to the appellants’ igniter)
is closed (col. 4, lines 73-74). However, a valve (7) is
opened increasingly by a heat sensitive device (12) in a
downstream catalytic converter unit (4) as soon as the
catalytic converter unit reaches its response temperature,
until the largest portion of the exhaust gases bypasses the
quick-warm-up catalytic unit (col. 3, lines 66-71; col. 4,
lines 18-23; col. 4, line 73 - col. 5, line 3). The catalyst
in the quick-warm-up catalytic unit increases the temperature
of the exhaust gases passing through it (col. 3, lines 52-62).
The exhaust gases from the quick-warm-up catalytic unit are
passed to the catalytic converter after the temperature of the
exhaust gases has been raised to a temperature to ignite the
catalyst within the catalyst bed of the catalytic converter
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(col. 4, lines 18-23; col. 4, line 75 - col. 5, line 3).
For the above reasons, the applied prior art would have
fairly suggested, to one of ordinary skill in the art, the
method recited in the appellants’ claim 22.
The appellants argue that Dunne and Säufferer do not
disclose bypassing any of the exhaust gases around an upstream
unit at start-up (brief, page 10). The appellants’ claim 22,
however, does not require such bypassing at start-up. What
the claim requires is that catalyst within an igniter is
permitted to increase the temperature of exhaust gases passing
through the igniter and that exhaust gases are passed through
a catalyst bed within a catalytic converter after a first
portion of the exhaust gases has passed through the igniter
and the temperature of the exhaust gases has been raised to a
temperature to ignite the catalyst within catalyst bed of the
catalytic converter. As discussed above, both Dunne and
Säufferer meet these requirements.
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The appellants argue that Dunne’s adsorbent zone is not a
catalyst (reply brief, page 2). Dunne, however, teaches that
a catalytic unit can be placed immediately after the adsorbent
zone and before the primary catalytic unit (col. 10, lines 1-
14).
For the above reasons we conclude that the method recited
in the appellants’ claim 22 would have been obvious to one of
ordinary skill in the art within the meaning of 35 U.S.C.
§ 103. We therefore affirm the rejection of this claim and
the claims which depend therefrom.
DECISION
The rejections under 35 U.S.C. § 103 of claims 4, 7, 8
and 21 over Rudy in view of Dunne and Säufferer, and claims 9-
11 over these references further in view of Abe, are reversed.
The rejections under 35 U.S.C. § 103 of claims 14-19 and 22
over Rudy in view of Dunne and Säufferer, and claim 20 over
these references further in view of Abe, are affirmed.
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No time period for taking any subsequent action in
connec- tion with this appeal may be extended under 37 CFR §
1.136(a).
AFFIRMED-IN-PART
)
CHARLES F. WARREN )
Administrative Patent Judge )
)
)
) BOARD OF PATENT
TERRY J. OWENS )
Administrative Patent Judge ) APPEALS AND
)
) INTERFERENCES
)
PAUL LIEBERMAN )
Administrative Patent Judge )
Appeal No. 1998-1133
Application 08/382,296

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BAKER & DANIELS
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