Ex Parte Lowe et alDownload PDFBoard of Patent Appeals and InterferencesJan 25, 201011022692 (B.P.A.I. Jan. 25, 2010) Copy Citation UNITED STATES PATENT AND TRADEMARK OFFICE ____________ BEFORE THE BOARD OF PATENT APPEALS AND INTERFERENCES ____________ Ex parte MICHAEL D. LOWE, WADE J. ROBEL, MAARTEN VERKIEL, and JAMES J. DRISCOLL ____________ Appeal 2009-001232 Application 11/022,692 Technology Center 3700 ____________ Decided: January 25, 2010 ____________ Before JENNIFER D. BAHR, LINDA E. HORNER, and MICHAEL W. O’NEILL, Administrative Patent Judges. O’NEILL, Administrative Patent Judge. DECISION ON APPEAL STATEMENT OF THE CASE Michael D. Lowe et al. (Appellants) seek our review under 35 U.S.C. § 134 of the second non-final rejection of claims 1-3, 5-31, and 39-45. Appeal 2009-001232 Application 11/022,692 2 Appellants canceled claims 4 and 32-38. We have jurisdiction under 35 U.S.C. § 6(b) (2002). The Invention The claimed invention is to techniques for on-vehicle filter desulfation. Spec. 1, para. [02]. Claim 1, reproduced below, is illustrative of the subject matter on appeal. 1. A method of removing sulfur from a filter system of an engine, comprising: continuously passing an exhaust flow through a desulfation leg of the filter system during desulfation; sensing at least one characteristic of the exhaust flow; and modifying a flow rate of the exhaust flow during desulfation in response to the sensing such that a desired desulfation temperature is held substantially constant. The Rejections The following Examiner’s rejections are before us for review: Claims 1-3, 5-31, 39-41, and 43-45 stand rejected under 35 U.S.C. § 102(e) as anticipated by Laroo (US 6,779,339 B1, issued Aug. 24, 2004). Claims 10 and 42 stand rejected under 35 U.S.C. § 102(b) as anticipated by Surnilla (US 6,189,316 B1, issued Feb. 20, 2001). Contentions Anticipation based on Laroo Claims 1, 2, 5, 8-13, 15-19, 20-27, and 29-31 Appellants contend that the Examiner erred in finding that the claimed subject matter of modifying the exhaust flow rate during desulfation in Appeal 2009-001232 Application 11/022,692 3 response to sensing a characteristic of the exhaust flow such that the desired desulfation temperature is held substantially constant, as called for in claims 1 and 20, is satisfied by Laroo. Appellants further contend that the Examiner erred in finding that the claimed subject matter of holding the desired temperature of an NOx absorber1 substantially constant during desulfation, as called for in claim 10, is satisfied by Laroo. Appellants contend that Laroo “teaches adjusting the engine exhaust flow only when the NOx adsorber temperature decreases below the ‘optimal’ desulfating temperature.” App. Br. 13. Appellants further contend that Laroo just teaches maintaining the temperature of desulfation above a certain threshold valve, but the temperature may vary above the threshold. App. Br. 13, 14, 17, and 19-21. Appellants additionally contend that the Examiner erred in finding that the temperature range mentioned in step F of Laroo (Laroo, col. 5, ll. 29-51) is also used for step G of Laroo (Laroo, col. 5, ll. 52-67). Appellants urge that Laroo does not disclose or suggest that, in step G, the temperature of the NOx adsorber catalyst is brought within the range of 500-750° C as the Examiner asserts. Reply Br. 2. Appellants urge that the Examiner erred in finding that the adsorber temperature being held within a range spanning 250° C corresponds to holding a temperature substantially constant. Id. Appellants contend that Laroo merely teaches increasing the temperature of the NOx adsorber catalyst up to some temperature between 500-750° C in step F and does not disclose or suggest holding the temperature within this 1 The claimed invention requires an absorber. Laroo discloses an adsorber. Absorption is a chemical process. Adsorption is a thermodynamic property. Appellants do not contend that, in this art, there could be a novel difference between an absorber and an adsorber. Appeal 2009-001232 Application 11/022,692 4 range in step F or step G as found by the Examiner. Reply Br. 3. Appellants urge that in step G, Laroo does not stop raising the temperature of the NOx adsorber as asserted by the Examiner. Id. Appellants contend that Laroo still increases the temperature of the NOx adsorber by allowing the catalytic diesel particulate filter (CDPF) to transfer heat to the NOx adsorber in step G. Id. Claims 3, 6, 7, 14, and 43 Appellants contend, arguendo, Laroo discloses that the fuel injection is modified to hold the lambda value2 substantially constant, the claimed subject matter of the flow rate of fuel being modified to hold the desulfating temperature substantially constant is not satisfied by Laroo. App. Br. 22. Appellants urge, because many factors may be adjusted to hold the desulfation temperature substantially constant, that maintaining a desired lambda value does not necessarily result in holding a desired desulfation temperature substantially constant. Id. at 22-23. Claim 28 that depends from claim 27 Appellants contend that Laroo discloses each exhaust leg of the exhaust system may operate in adsorption mode or denitration mode when not being operated in desulfation mode. App. Br. 23. Appellants contend that in adsorption mode, the flow rate of the exhaust is not restricted and thus Laroo does not anticipate the claimed subject matter of restricting the flow rate of the exhaust flow through the desulfation leg. Id. Appellants further contend that Laroo discloses fuel is injected into the exhaust path during the denitration mode and thus Laroo cannot anticipate the claimed 2 A lambda (λ) value is the air-to-fuel ratio within the exhaust. A value less than 1 indicates a rich fuel environment within the exhaust. Appeal 2009-001232 Application 11/022,692 5 subject matter of stopping the injection of reductant into the exhaust flow. Appellants urge that the Examiner erred in finding that stopping the injection of fuel in one leg during denitration and restricting the exhaust flow rate in the other leg during adsorption “controllably cool[s] the NOx adsorber after desulfation.” App. Br. 24. According to Appellants, these two actions occur in separate exhaust legs of Laroo after desulfation occurs in one of the legs and thus do not anticipate the claimed subject matter of controllably cooling the NOx absorber of the desulfation leg after desulfation. Appellants contend that controllably cooling the NOx absorber includes stopping an injection of reductant into the exhaust flow and restricting the flow rate of the exhaust through the desulfation leg. App. Br. 24. Claims 39, 40, and 44 Appellants contend that Laroo fails to anticipate the claimed subject matter of cooling the NOx adsorber to hold the desired desulfation temperature substantially constant because Laroo discloses heating the NOx adsorbers, not cooling them. App. Br. 24-26. Appellants contend that Laroo discloses when it is operating in desulfation mode, the temperatures in the desulfation leg increase even when the flow is restricted to less than five percent of the total flow because fuel is supplied to each CDPF. Id. Claims 41 and 45 Appellants contend that Laroo’s disclosure of initiating desulfation automatically on a periodic basis and that the timing of desulfation initiation may depend on a characteristic of the NOx adsorber, viz., storage capacity, does not anticipate the claimed subject matter of determining whether to initiate desulfation based on a particular sensed characteristic. App. Br. 27. Appeal 2009-001232 Application 11/022,692 6 Anticipation based on Surnilla Appellants contend that the Examiner erred in finding Surnilla anticipates the process step of “injecting a reductant into an exhaust flow upstream of the NOx absorber” because Surnilla discloses that fuel and air are injected into the cylinders, and as such, the fuel is not injected into an exhaust flow. Reply Br. 4-5; see also App. Br. 29-30. SUMMARY OF DECISION We AFFIRM-IN-PART. OPINION Issues In light of the Appellants’ contentions, the issues before us are as follows: Have Appellants shown the Examiner erred in finding that Laroo anticipates: (1) modifying the exhaust flow rate during desulfation in response to sensing an exhaust flow characteristic such that the desired desulfation temperature is held substantially constant? (2) holding the desired temperature of an NOx absorber substantially constant during desulfation? (3) modifying a flow rate of a reductant in response to sensing an exhaust flow characteristic in order to hold the desired desulfation temperature substantially constant? (4) controllably cooling an NOx absorber of the desulfation leg after desulfation, in particular, by stopping the injection of Appeal 2009-001232 Application 11/022,692 7 reductant into the exhaust flow and restricting the flow rate of the exhaust flow through the desulfation leg? (5) modifying the exhaust flow rate to cool the desulfation leg in order to hold the desired desulfation temperature substantially constant? (6) holding the desired temperature substantially constant during desulfation by cooling the desulfation leg? (7) determining whether to initiate desulfation based on sensing either a characteristic of the engine or engine filter system? Additionally, have Appellants shown the Examiner erred in finding that Surnilla anticipates: (8) the process step of injecting a reductant into an exhaust flow upstream of the NOx absorber? Pertinent Facts 1. Laroo discloses a method and apparatus for desulfating NOx adsorber catalysts in a multi-exhaust path flow system utilizing in-exhaust fuel injection and exhaust flow bypass. Col. 1, ll. 55-58. The process minimizes temperature extremes and maintains precise temperatures on the NOx adsorber for desulfation. Col. 1, ll. 58-60. The multi- exhaust path flow system includes a perpendicular exhaust path loop that allows a controlled addition of exhaust from the adsorbing leg to the desulfation leg. Col. 2, ll. 20-24. Laroo discloses that the NOx adsorber can be heated to the desired temperature by permitting a small fraction of exhaust flow through the desulfation leg in conjunction with a perpendicular exhaust bypass loop flow, or momentarily opening the desulfation leg to the full exhaust flow. Col. Appeal 2009-001232 Application 11/022,692 8 2, ll. 16-18 and 39-41. Once the NOx adsorber is heated to the desired temperature, a reductant is added to facilitate sulfur release. Col. 2, ll. 42-44. 2. Laroo discloses that the NOx adsorber is maintained at the desired desulfation temperature by controlling the perpendicular exhaust bypass loop flow. Col. 2, ll. 44-47. 3. Laroo discloses that both the NOx adsorber and the catalytic diesel particulate filter (CDPF) have temperature sensors that send signals to the controller. Based on the signals sent by the sensors, the controller controls the fuel (reductant) injectors, exhaust flow valves, and exhaust bypass control valve. Col. 4, ll. 7-32. 4. Laroo discloses that the desulfation for the NOx adsorber in each flow path (leg) is initiated periodically and automatically based on a threshold of loss in the storage capacity of the NOx adsorber. Col. 5, ll. 11-14. 5. Laroo discloses that the exhaust flow is restricted for an exhaust flow path (leg) undergoing desulfation. At this time, fuel (reductant) is sprayed into the exhaust flow passing over the catalytic diesel particulate filter (CDPF) and the perpendicular bypass valve is opened. The introduction of reductant and bypass exhaust flow continues until the CDPF reaches a first predetermined temperature. When the CDPF reaches that temperature, reductant and exhaust flow are discontinued. Col. 5, ll. 15-23. 6. Laroo discloses that, for the exhaust path that is undergoing desulfation, when the catalytic diesel particulate filter (CDPF) reaches the first predetermined temperature, heat is transferred, by convection, Appeal 2009-001232 Application 11/022,692 9 from the CDPF to the NOx adsorber in order to bring the NOx adsorber catalyst up to the desired desulfating temperature. The desired desulfating temperature for a given NOx adsorber is based on the specific NOx adsorber catalyst formulation. Laroo discloses that the desired desulfation temperature ranges between 500-750° C. Col. 5, ll. 29-36. 7. Laroo discloses that in order to reach the desired desulfation temperature based on the catalyst’s formulation, one of two process occur. Either the perpendicular bypass valve is opened to control exhaust flow into the leg or full engine exhaust flow travels through the leg. Col. 5, ll. 37-40. 8. Laroo discloses that another predetermined temperature set point is used to close exhaust flow to the exhaust leg undergoing desulfation. This temperature is based on the cooling effect of the exhaust flow on the catalytic diesel particulate filter (CDPF). Col. 5, ll. 40-44. 9. Laroo discloses either when the catalytic diesel particulate filter (CDPF) reaches a third predetermined temperature or when the NOx adsorber reaches its second predetermined temperature, the exhaust flow occurring within the leg undergoing desulfation ceases. Col. 5, ll. 44-47. 10. Laroo discloses once the exhaust flow ceases, therefore, the NOx adsorber is at the desired desulfation temperature, fuel (reductant) is sprayed into the exhaust leg on to the catalytic diesel particulate filter (CDPF) and the exhaust flow is returned to the desulfating exhaust flow, about five percent of the full exhaust flow. The spraying of reductant is controlled by monitoring the λ/NOx (lambda/NOx) Appeal 2009-001232 Application 11/022,692 10 sensors. The spraying of reductant causes the sulfur to be released from the NOx adsorber. Col. 5, ll. 52-60 11. Laroo discloses that if the temperature of the NOx adsorber catalyst falls below the optimal desulfation temperature during sulfur release, then the leg undergoing desulfation is again contacted with engine exhaust flow to initiate an exotherm across the catalytic diesel particulate filter (CDPF). As such, heat is again generated and convectively transferred to the NOx adsorber to maintain the NOx adsorber temperature. Col. 5, ll. 62-67. 12. Surnilla discloses operating certain cylinders in a rich condition and, as such, these cylinders would produce exhaust gas with unburned hydrocarbons. Surnilla, col. 2, ll. 59-60. Surnilla discloses that this process is used to achieve the desired rich bias. This rich bias releases the stored sulfur within the NOx trap when the trap is at the proper desulfation temperature. Surnilla, col. 4, ll. 23-29. Analysis Issue (1) Appellants’ contentions do not demonstrate that the Examiner erred in finding that Laroo anticipates the claimed subject matter of modifying a flow rate of the exhaust flow in an exhaust leg during desulfation in response to sensing one characteristic of the exhaust flow, as called for in claim 1. Laroo discloses a method and apparatus for desulfating NOx adsorbers in a multi-path exhaust flow system. Fact 1. Laroo discloses that the NOx adsorber undergoing desulfation is heated to a desired temperature by controlling the exhaust flow through the exhaust leg either by permitting a small amount of exhaust through the leg and over the CDPF or by Appeal 2009-001232 Application 11/022,692 11 momentarily opening the leg to the full exhaust flow. Facts 1 and 7. Laroo discloses that the desired temperature for desulfation of the NOx adsorber is based on the catalyst formulation within the NOx adsorber. Fact 6. Laroo discloses that the desired temperature for desulfation falls within the range of 500-750° C. Fact 6. Thus, Laroo discloses that for a given catalyst formulation within an NOx adsorber there is a desired temperature for desulfation for that NOx adsorber that falls within the range of 500-750° C. While the desired temperature for a given catalyst formulation will fall within a range, the particular desired temperature is a temperature, and not a range. Appellants’ argument that the NOx adsorber temperature discussed for step F is not also used for step G, and that the NOx adsorber can vary above the threshold, is not well founded. In both steps F and G, heat transfer occurs until the desired, or optimal, desulfating temperature is reached. See Facts 9 and 11. Laroo discloses that the NOx adsorber is maintained at the desired temperature for desulfation by controlling the perpendicular exhaust bypass loop flow. Fact 2. Controlling the perpendicular exhaust bypass loop flow is achieved by the controller controlling the exhaust valves based on signals received from at least the temperature sensors. Fact 3. The temperature sensors would either indirectly or directly sense the temperature of the exhaust gas through the devices that the sensors are attached to. Controlling the exhaust flow by manipulating exhaust valves for a leg undergoing desulfation is modifying the exhaust flow rate of the exhaust flow through the leg. Sensing the temperature of the exhaust flow is sensing a characteristic of the exhaust flow. Maintaining a desulfation temperature based on the catalyst formulation is holding a desired desulfation Appeal 2009-001232 Application 11/022,692 12 temperature substantially constant. As such, the process step within claim 1 of modifying a flow rate of the exhaust flow during desulfation in response to sensing an exhaust flow characteristic such that a desired desulfation temperature is held substantially constant is satisfied by Laroo’s disclosure for the reasons given supra. Appellants do not separately argue claims 2, 5, 8, 9, 27, and 29-31. As such, these claims fall with claim 1 for the reasons given supra. Appellants’ contentions do not demonstrate that the Examiner erred in finding Laroo anticipates the function of modifying a flow rate of a portion of exhaust flow from an engine with a valving mechanism, during desulfation, in response to a sensed temperature, such that a desired desulfation temperature is held substantially constant, as called for in claim 20. As discussed supra with claim 1, Laroo modifies the flow rate, by use of exhaust valves, of exhaust gas passing through the exhaust leg undergoing desulfation in order to maintain the NOx adsorber at the temperature needed for desulfation based on the catalyst formulation of the NOx adsorber. As such, the element within claim 20 of a valving mechanism that modifies the flow rate of a portion of exhaust flow from the engine through the exhaust leg, during desulfation, in response to a sensed temperature, such that a desired desulfation temperature is held substantially constant, is satisfied by Laroo’s disclosure for the reasons given supra. Appellants do not separately argue claims 21-26. As such, these claims fall with claim 20 for the same reasons. Issue (2) Appellants’ contentions do not demonstrate that the Examiner erred in finding Laroo anticipates the process step of holding the desired temperature Appeal 2009-001232 Application 11/022,692 13 of a NOx absorber substantially constant during desulfation, as called for in claim 10. As discussed supra with claim 1, Laroo’s disclosure describes maintaining the desired temperature of a NOx adsorber at a particular temperature for the catalyst formulation of the NOx adsorber. Maintaining the temperature at a predetermined temperature based on the catalyst formulation is holding the desired temperature substantially constant. Laroo maintains the temperature at a temperature within the range of 500-750° C in order for desulfation to occur within the NOx adsorber. As such, the process step within claim 10 of holding the desired temperature of an NOx absorber substantially constant during desulfation is satisfied by Laroo’s disclosure for the reasons given supra. Appellants do not separately argue claims 11-13 and 15-19. As such, these claims fall with claim 10 for the same reasons. Issue (3) Appellants’ contentions demonstrate that the Examiner erred in finding Laroo anticipates the claimed subject matter of modifying the flow rate of the reductant in response to sensing an exhaust flow characteristic to hold the desired desulfation temperature substantially constant. Laroo discloses controlling, and thus modifying, the reductant injection to maintain the desired lambda value as monitored by the lambda/NOx sensors. Fact 10. However, as Appellants argue, controlling the injection of reductant to maintain a lambda value is not necessarily controlling the injection of reductant to maintain the temperature of the NOx adsorber. Instead, Laroo discloses that heat is convectively transferred from the CDPF to the NOx adsorber by allowing exhaust flow to initiate an exotherm across the CDPF Appeal 2009-001232 Application 11/022,692 14 to maintain the temperature of the NOx adsorber substantially constant. Fact 10. In view of the foregoing, Appellants have demonstrated that the Examiner erred in finding Laroo anticipates claims 3, 6, 7, 14, and 43. Issue (4) Appellants’ contentions demonstrate that the Examiner erred in finding Laroo anticipates the claimed subject matter of controllably cooling the desulfation leg by stopping the injection of reductant and restricting the exhaust flow. The Examiner’s finding that Laroo’s disclosure that the system switches the flow paths and injecting reductant, and the Examiner’s analysis that both legs of the exhaust have the desulfating process performed on them (Ans. 15), is not enough to support a finding that Laroo explicitly anticipates controlling the cooling of the NOx absorber by stopping the injection of reductant and restricting the exhaust flow, as called for within claim 28. Nor does it necessarily flow from Laroo’s disclosure that a controlled cooling of the NOx adsorber includes the steps of stopping an injection of reductant into the exhaust flow and restricting the flow rate of the exhaust flow through the desulfating leg. However, Laroo’s disclosure of switching the exhaust flow does anticipate a controlled cooling of an NOx absorber as claimed after desulfation because, if the NOx adsorber was maintained at the desulfation temperature for an extended period of time, degradation would occur within the NOx adsorber kept at such high temperature. See e.g., Laroo, col. 1, ll. 60-62 (Fact 1). As such, controllably cooling the NOx absorber is satisfied by Laroo’s disclosure, but controllably cooling the NOx absorber by Appeal 2009-001232 Application 11/022,692 15 stopping the injection of reductant and restricting the flow rate of the exhaust is not satisfied by Laroo’s disclosure. In view of the foregoing, Appellants have demonstrated that the Examiner erred in finding Laroo anticipates claim 28. However, Appellants have not demonstrated that the Examiner erred in finding Laroo anticipates claim 27. Issues (5) and (6) Appellants have not demonstrated that the Examiner erred in finding that Laroo anticipates modifying the exhaust flow rate to cool the desulfation leg in order to hold the desired desulfation temperature substantially constant, as called for in claims 39 and 44, or holding the desired temperature substantially constant during desulfation by cooling the desulfation leg, as called for in claim 40. As discussed supra, Laroo’s disclosure describes holding the desired temperature substantially constant by permitting exhaust flow to pass in a controlled manner after raising the NOx adsorber to a predetermined temperature for the given catalyst formulation of the NOx adsorber. Laroo’s disclosure describes that another predetermined temperature set point is used to close the exhaust flow to the exhaust leg undergoing desulfation and this temperature is based on the cooling effect of the exhaust flow on the CDPF. Fact 8. Laroo describes that heat is transferred by convection from the CDPF to the NOx adsorber. Fact 6. Since the NOx adsorber is downstream from the CDPF and the temperature of the NOx adsorber is dependent on the temperature of the CDPF, see Fact 6, the NOx adsorber would cool because the heat transfer from the CDPF would cease. See also Fact 9 (finding that when either the Appeal 2009-001232 Application 11/022,692 16 CDPF or NOx adsorber reaches a predetermined temperature exhaust flow ceases). A person having ordinary skill in the art would understand that, as Laroo describes achieving precise temperatures required for desulfation, see e.g. Laroo, col. 1, ll. 59-60 (Fact 1), in order to maintain the NOx adsorber at the precise desulfation temperature, both heating and cooling the NOx adsorber would be necessary. Appellants’ arguments do not persuade us that the flow rate of exhaust would not be modified in order to maintain the NOx adsorber at the precise desulfation temperature, when Laroo, while not expressly referring to cooling the NOx adsorber, expressly states that the exhaust flow is modified in order to maintain the precise desulfation temperature. Fact 11. As such, the claimed subject matter within claims 39, 40, and 44, of modifying the exhaust flow rate to cool the desulfation leg in order to hold the desired desulfation temperature substantially constant or holding the desired temperature substantially constant during desulfation by cooling the desulfation leg is satisfied by Laroo’s disclosure for the reasons given supra. Issue (7) Appellants’ contentions do not demonstrate that the Examiner erred in finding Laroo anticipates determining whether to initiate desulfation based on sensing either a characteristic of the engine or engine filter system. Laroo discloses initiating desulfation of the NOx adsorber periodically and automatically based on a threshold of loss in the storage capacity of the NOx adsorber. Fact 4. Laroo discloses that the multi-leg exhaust system has NOx, temperature, and lambda sensors that send signals to the controller. Fact 3. Sensing NOx, temperature, or lambda value within an exhaust leg is Appeal 2009-001232 Application 11/022,692 17 sensing a characteristic of the engine filter system. Initiating desulfation based on a schedule of hours is sensing a characteristic of the engine, the time of operation. As such, the process step or function within claims 41 and 45 of determining whether to initiate desulfation based on sensing either a characteristic of the engine or engine filter system is satisfied by Laroo’s disclosure for the reasons given supra. Issue (8) Appellants’ contentions do not demonstrate that the Examiner erred in finding Surnilla anticipates the claimed subject matter of injecting a reductant into an exhaust flow upstream of the NOx absorber. Surnilla discloses operating certain cylinders in a rich condition and, as such, these cylinders would produce exhaust gas with unburned hydrocarbons. Fact 12. The unburned hydrocarbons, the slight rich bias, are the reductant that releases the stored sulfur within the NOx trap3 when the trap is at the proper desulfation temperature. Id. Claim 10 requires injecting a reductant into an exhaust flow upstream of the NOx absorber. Claim 10 does not limit the injection to be directly into the exhaust flow; the claim language is broader. We must be careful not to read a particular embodiment appearing in the written description into the claim if the claim language is broader than the embodiment. See Superguide Corp. v. DirecTV Enterprises, Inc., 358 F.3d 870, 875 (Fed. Cir. 2004) (“Though understanding the claim language may be aided by the explanations contained in the written description, it is important not to import into a claim limitations that are not a part of the claim. For example, a particular embodiment appearing in the written 3 Appellants do not dispute that an NOx absorber is satisfied by a disclosure of the NOx trap within Surnilla. Appeal 2009-001232 Application 11/022,692 18 description may not be read into a claim when the claim language is broader than the embodiment.”) Appellants’ contention requests us to read a particular embodiment into the claim. We decline. As such, Laroo anticipates the claimed subject matter within claim 10 of injecting a reductant into an exhaust flow upstream of the NOx absorber for the reasons given supra. Appellants do not separately argue the rejection of claim 42. As such, claim 42 falls with claim 10 for the same reasons. CONCLUSIONS Appellants have not shown the Examiner erred in finding that Laroo anticipates: • modifying the exhaust flow rate during desulfation in response to sensing an exhaust flow characteristic such that the desired desulfation temperature is held substantially constant. (Issue 1). • holding the desired temperature of an NOx absorber substantially constant during desulfation. (Issue 2). • modifying the exhaust flow rate to cool the desulfation leg in order to hold the desired desulfation temperature substantially constant. (Issue 5). • holding the desired temperature substantially constant during desulfation by cooling the desulfation leg. (Issue 6). • determining whether to initiate desulfation based on sensing either a characteristic of the engine or engine filter system. (Issue 7). Appeal 2009-001232 Application 11/022,692 19 Appellants have shown the Examiner erred in finding that Laroo anticipates: • modifying a flow rate of a reductant in response to sensing an exhaust flow characteristic in order to hold the desired desulfation temperature substantially constant. (Issue 3). • controllably cooling an NOx absorber of the desulfation leg after desulfation, in particular, by stopping the injection of reductant into the exhaust flow and restricting the flow rate of the exhaust flow through the desulfation leg. (Issue 4). Appellants have not shown the Examiner erred in finding that Surnilla anticipates the process step of injecting a reductant into an exhaust flow upstream of the NOx absorber. (Issue 8). DECISION The Examiner’s decision to reject claims 1, 2, 5, 8-13, 15-27, 29-31, 39-42, 44, and 45 is affirmed. The Examiner’s decision to reject claims 3, 6, 7, 14, 28, and 43 is reversed. No time period for taking any subsequent action in connection with this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R. § 1.136(a)(1)(iv) (2007). AFFIRMED-IN-PART Appeal 2009-001232 Application 11/022,692 20 mls CATERPILLAR/FINNEGAN, HENDERSON, L.L.P. 901 NEW YORK AVENUE, NW WASHINGTON, DC 20001-4413 Copy with citationCopy as parenthetical citation