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

1. Case Identification

• Patent #: 5,655,365
• Filed: June 6, 1995
• Petitioner(s): Robert Bosch LLC and Daimler AG
• Patent Owner(s): Orbital Engine Company Pty Limited
• Challenged Claims: 1, 2, 5, 9, 10, 12-14, and 18

2. Patent Overview

• Title: Method of Operating an Internal Combustion Engine
• Brief Description: The ’365 patent describes a method for operating an internal combustion engine to rapidly increase exhaust gas temperature during startup. This is achieved by retarding ignition timing to after top dead center (ATDC) while simultaneously increasing the fueling rate, thereby quickly heating a catalytic converter to its effective operating temperature ("light-off") to reduce harmful emissions.

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 disclosed the core elements of claim 1, including a method for warming up an engine's catalytic device by retarding ignition to ATDC (between 10° and 20°) and increasing the rate of fuel injection to compensate for increased exhaust load during warm-up. However, Hitomi did not explicitly teach that all fuel must be introduced before top dead center (BTDC), specifically within the 60° to 80° BTDC range recited in dependent claim 9. Onishi was cited to supply this missing element, as it disclosed a fuel injection method where all fuel is introduced in a cycle between 80° and 60° BTDC for engines operating from idle to full-load conditions. Onishi also disclosed that its fuel injection timing could be used with an increased fueling rate greater than 50% of the maximum, satisfying claim 2.
  • Motivation to Combine: A person of ordinary skill in the art (POSITA) would combine Onishi's established fuel injection timing with Hitomi's catalyst warm-up strategy. The motivation was to achieve a more homogeneous air/fuel mixture, leading to more stable and efficient combustion when implementing Hitomi's retarded ignition method, particularly during engine idle and cold start conditions.
  • Expectation of Success: A POSITA would have a reasonable expectation of success because both references related to controlling ignition and fuel timing in internal combustion engines to manage performance and emissions, and Onishi explicitly stated its method was compatible with independent variation of ignition timing.

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 1447791), and Onishi (Patent 3,572,298).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner asserted that Griese taught a system for quickly heating an exhaust gas cleaning device during a cold or idle run by delaying ignition timing and using an "abnormally high quantity of fuel-air mixture." While Griese taught the concept of delayed ignition to generate heat, it did not explicitly disclose retarding ignition to after top dead center. Eichler '791 was introduced to teach this specific feature, as it disclosed retarding ignition to a range of 15° to 25° ATDC to reduce engine braking. The combination of Griese and Eichler '791 allegedly rendered the core method of claims 1 and 5 obvious. As with the first ground, Onishi was used to supply the teaching of injecting all fuel BTDC, specifically between 60° and 80° BTDC (claim 9).
  • Motivation to Combine: A POSITA would be motivated to apply the specific ATDC ignition retard range from Eichler '791 to Griese's catalyst heating method to more effectively convert combustion energy into exhaust heat with less mechanical work, an objective recognized by Griese. The motivation to add Onishi's fuel injection timing was to achieve the stable and assured combustion necessary for the engine to operate reliably under the cold-start, retarded-ignition conditions taught by Griese and Eichler '791.
  • Expectation of Success: Success was expected because the references address compatible and known trade-offs in engine control, where ignition timing, fuel timing, and fuel quantity are routinely adjusted to optimize for factors like power, efficiency, and emissions under various operating conditions.

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 paper).

• Core Argument for this Ground:

  • Prior Art Mapping: Petitioner argued that Ahern disclosed a method for controlling direct fuel injection timing, including injecting fuel in a window that falls between 60° and 80° BTDC (satisfying claim 9). However, Ahern did not teach retarding ignition to ATDC or increasing the fueling rate for the purpose of heating a catalyst. Bernhardt was cited to supply these missing features. Bernhardt taught a well-known method of using the engine as a "preheater" for a catalytic system by employing "warm-up spark retard" to as much as 50° ATDC and increasing fuel flow (with a fully opened throttle) to rapidly raise exhaust gas temperature. Bernhardt's disclosure of operating with a fully open throttle and increased fuel flow was argued to teach a fueling rate greater than 50% of maximum load (claim 2).
  • Motivation to Combine: A POSITA would be motivated to incorporate the established catalyst warm-up strategy from Bernhardt into the direct-injection engine control system of Ahern. The goal was to reduce harmful contaminants during cold starts, a primary challenge in engine design. A POSITA would apply Bernhardt's teachings on ignition retard and increased fueling to Ahern's system to ensure rapid catalyst light-off.
  • Expectation of Success: A POSITA would expect success because combining a known warm-up strategy (Bernhardt) with a known fuel injection control method (Ahern) was a straightforward application of known principles to solve a known problem.

• Additional Grounds: Petitioner asserted additional obviousness challenges, including combining Hitomi and Onishi with Eichler '089 (for claim 5) or Takada (for claim 12), and combining Ahern and Bernhardt with Griese (for claim 14). These grounds relied on the same core combinations but added tertiary references to teach specific features of dependent claims, such as introducing additional air upstream of the catalyst (Takada) or sensing catalyst temperature (Griese).

4. Key Claim Construction Positions

• "up to about 30° ATDC" (Claim 5): Petitioner argued this term should be construed to mean "between 15° and about 30° ATDC." This construction was based on the patent's specification, which only described embodiments and advantages for ignition retard within that specific range and provided no disclosure for retarding ignition between top dead center (TDC) and 15° ATDC.
• "the timing of introduction of fuel... being maintained at before top dead centre (BTDC)" (Claim 1): Petitioner contended 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 interpretation was based on prosecution history, where the "maintained at" language was added to overcome a prior art rejection (Morikawa), and on figures in the '365 patent that contrasted typical operation with the invention by showing only the ignition timing changing, while the fuel introduction timing was "maintained."

5. Relief Requested

• Petitioner requested 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.