PTAB

IPR2015-01259

1 Robert Bosch LLC 2 Daimler AG v. Orbital Australia Pty Ltd

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Method of Operating an Internal Combustion Engine
  • Brief Description: The ’365 patent discloses a method for rapidly heating an internal combustion engine’s catalytic converter during a cold start to reduce harmful emissions. The method involves retarding the ignition timing of the air/fuel mixture to after top dead center (ATDC) while simultaneously increasing the fuelling rate, which raises the exhaust gas temperature to the catalyst’s light-off temperature more quickly.

3. Grounds for Unpatentability

Ground 1: Claims 1, 2, 9, 10, 13, 14, and 18 are obvious over Hitomi in view of Onishi

  • Prior Art Relied Upon: Hitomi (Patent 5,233,831) and Onishi (Patent 3,572,298).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Hitomi discloses the core elements of the challenged method, including retarding ignition to ATDC during engine warm-up and increasing the rate of fuel injection to compensate for increased exhaust load and promote catalyst activation. However, Hitomi does not explicitly teach that all fuel is introduced before top dead center (BTDC), specifically within the 60° to 80° BTDC range recited in claim 9. Petitioner asserted that Onishi, a well-known reference in the art, remedies this by teaching a fuel injection method where all fuel is injected between 60° and 80° BTDC over a range of engine conditions, including idling and cold starts.
    • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would combine the teachings of Hitomi and Onishi to improve combustion efficiency. Implementing Onishi’s fuel injection timing (all fuel injected between 60°-80° BTDC) into Hitomi’s catalyst warm-up strategy would provide a more homogeneous air/fuel mixture, leading to more stable and efficient combustion during the low-load and cold-start conditions addressed by both references.
    • Expectation of Success: A POSITA would have had a reasonable expectation of success because Onishi explicitly teaches that ignition timing can be varied independently of fuel injection timing. This would have assured a POSITA that applying Hitomi’s ATDC ignition retard would not negatively interfere with Onishi’s BTDC fuel injection method.

Ground 2: Claims 1, 2, 5, 9, 10, 13, 14, and 18 are obvious over Griese in view of Eichler ’791 and Onishi

  • Prior Art Relied Upon: Griese (Patent 3,799,134), Eichler ’791 (GB Patent No. 1447791), and Onishi (Patent 3,572,298).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner contended that Griese teaches a method for heating an exhaust gas cleaning device during a cold start by delaying ignition timing and providing a "maximum possible fuel supply." While Griese teaches "delayed" ignition to increase exhaust heat, it does not explicitly disclose retarding ignition to ATDC. Petitioner asserted that Eichler ’791 supplies this limitation by disclosing a device that retards ignition to between 15° and 25° ATDC. As in the previous ground, Onishi was relied upon to teach the introduction of all fuel between 60° and 80° BTDC.
    • Motivation to Combine: A POSITA would combine Eichler ’791’s specific ATDC retard range with Griese’s general heating method to more effectively and efficiently convert combustion energy into exhaust gas heat, a recognized goal in Griese. A POSITA would further incorporate Onishi’s fuel injection strategy to ensure an optimal air/fuel mixture, leading to the stable combustion necessary for the cold and idle run conditions described in Griese and Eichler ’791.
    • Expectation of Success: The proposed combination involves the optimization of known engine operating parameters (ignition timing, fuel injection strategy) for the predictable purpose of heating an exhaust catalyst. Petitioner argued this amounts to routine experimentation within the predictable arts.

Ground 3: Claims 1, 2, 5, 9, 10, 12, 13, and 18 are obvious over Ahern in view of Bernhardt

  • Prior Art Relied Upon: Ahern (Patent 4,926,806) and Bernhardt (a 1972 Society of Automotive Engineers publication).

  • Core Argument for this Ground:

    • Prior Art Mapping: Petitioner argued that Ahern discloses a direct injection engine control method that includes injecting fuel between 60° and 80° BTDC during startup. However, Ahern does not teach retarding ignition to ATDC or increasing the fuelling rate for catalyst heating. Petitioner asserted that Bernhardt teaches all the remaining claim elements, disclosing a method to use an engine as a "preheater" for a catalytic system by employing "extreme spark retard" up to 50° ATDC and increasing fuel flow with a "fully opened throttle." Bernhardt also teaches that this method is used during cold starts and results in a fuelling rate of approximately 83% of the rate at maximum load.
    • Motivation to Combine: A POSITA would have been motivated to combine Bernhardt's well-known catalyst heating strategy with Ahern's engine control system to solve the known problem of cold-start emissions. Furthermore, a POSITA would recognize that the torque loss caused by Bernhardt's ignition retard would need to be compensated for, motivating the adoption of Bernhardt's corresponding teaching of an increased fuelling rate.
    • Expectation of Success: Applying Bernhardt's established emissions-reduction technique to Ahern's fuel injection system would have been a predictable implementation of known engineering principles to achieve the known and desired result of rapid catalyst warm-up.

  • Additional Grounds: Petitioner asserted additional obviousness challenges, including adding Eichler ’089 (Patent 3,865,089) to the Hitomi/Onishi combination to teach a broader range of ignition retard for claim 5, and adding Takada (Patent 4,276,745) to teach the introduction of secondary air for claim 12.

4. Key Claim Construction Positions

  • "the timing of introduction of fuel... being maintained at before top dead centre (BTDC)" (Claim 1): Petitioner argued this phrase should be construed to mean "all fuel introduced into the at least one cylinder during a combustion cycle is controlled to occur BTDC." This construction was based on arguments made during prosecution to overcome prior art, where the patent owner amended the claim to add this limitation to distinguish a reference (Morikawa) that retarded ignition while increasing fuel injection amount.
  • "up to about 30° ATDC" (Claim 5): Petitioner proposed this phrase should be construed to mean "between 15° and about 30° ATDC." Petitioner contended that the patent’s specification only discloses and supports engine operation where ignition is retarded to this specific range, and provides no disclosure explaining how retarding ignition to between TDC and 15° ATDC would achieve the patent's stated objective.

5. Relief Requested

  • Petitioner requests the institution of an inter partes review and cancellation of claims 1, 2, 5, 9, 10, 12-14, and 18 of Patent 5,655,365 as unpatentable.