PTAB

IPR2015-00792

Ford Motor Co v. Paice LLC

Log In
Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Hybrid Vehicles
  • Brief Description: The ’097 patent describes a control system for a hybrid electric vehicle (HEV) having an internal combustion engine, an electric motor, and a battery. The system’s controller manages the operational modes to improve fuel economy and reduce emissions by operating the engine primarily in its most efficient range and maintaining a substantially stoichiometric air-fuel ratio during combustion.

3. Grounds for Unpatentability

Ground 1: Claims 1, 7, 9, 11, 17, 19, 21, 27, 28, 30, 37, and 38 are obvious over Severinsky in view of Takaoka.

  • Prior Art Relied Upon: Severinsky (Patent 5,343,970) and Takaoka (Toyota Technical Review, Apr. 1998).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Severinsky disclosed the fundamental HEV architecture and control strategy recited in the independent claims. Specifically, Severinsky taught a controller that determines the required propulsion torque (i.e., road load) and operates the vehicle in different modes based on that torque. The engine is used when it can operate efficiently (e.g., producing 60-90% of its maximum torque), and the electric motor is used for lower torque requirements or to supplement the engine. Petitioner asserted that Takaoka taught the key emissions control strategy missing from Severinsky: limiting the rate of increase of engine torque output to reduce "quick transients" in engine load. This technique allows the air-fuel ratio to be stabilized at or near the stoichiometric ratio, which is necessary for efficient operation of a three-way catalyst to reduce emissions and maximize fuel efficiency.
    • Motivation to Combine: A Person of Ordinary Skill in the Art (POSA) would combine Severinsky’s HEV control system with Takaoka’s well-known emissions control technique to achieve the recognized industry goals of improved fuel economy and reduced pollutant emissions. Severinsky’s objective was to create an improved HEV, and Takaoka provided a known, superior solution for managing emissions and improving efficiency compared to the lean-burn strategy also discussed in Severinsky. The combination would have been a predictable implementation of a known technique to improve a known system for its intended purpose.
    • Expectation of Success: A POSA would have had a reasonable expectation of success in this combination. Takaoka’s strategy of limiting the rate of torque increase is a control algorithm modification. The microprocessor-controlled system in Severinsky was inherently capable of implementing such algorithms to predictably achieve the benefits of stabilized stoichiometric combustion taught by Takaoka.

Ground 2: Claims 3, 4, 13, 14, 23, 24, 32, and 33 are obvious over Severinsky in view of Takaoka and Yamaguchi.

  • Prior Art Relied Upon: Severinsky (Patent 5,343,970), Takaoka (Toyota Technical Review, Apr. 1998), and Yamaguchi (Patent 5,865,263).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground built upon Ground 1 by adding Yamaguchi to address dependent claims related to engine starting procedures. Petitioner argued that Yamaguchi disclosed rotating an engine to at least 300 rpm (specifically, 600 rpm) before fuel is supplied for ignition. This action heats the engine through friction and compression, which is a known method to improve combustion and reduce emissions during cold starts, thereby satisfying the limitations of claims 3, 13, 23, and 32. For claims 4, 14, 24, and 33, which required a specific fuel-air ratio for starting, Petitioner contended that Takaoka’s teaching of operating the engine at a stoichiometric ratio over its entire range necessarily included engine starts.
    • Motivation to Combine: A POSA seeking to optimize the HEV of Severinsky and Takaoka would have been motivated to address the well-known problem of high emissions during cold starts. Yamaguchi provided a known, effective solution to this specific problem. Incorporating Yamaguchi's pre-heating start strategy into the existing control logic was a logical next step to further improve the vehicle's overall performance and emissions profile, particularly in reducing cold-start emissions which are a significant contributor to overall pollution.
    • Expectation of Success: The combination would have been a predictable integration of known technologies. A POSA could have readily modified the control algorithms of the Severinsky/Takaoka system to include the start-up sequence taught by Yamaguchi, with a high expectation of successfully reducing cold-start emissions and improving fuel economy.

4. Key Claim Construction Positions

  • "road load (RL)": Petitioner proposed construing this term as "the amount of instantaneous torque required to propel the vehicle, be it positive or negative." This construction was central to arguing that Severinsky’s control strategy, which is based on the required propulsion torque, mapped directly to the claim limitations.
  • "setpoint (SP)": Petitioner argued that the broadest reasonable construction is "a predetermined torque value." This was critical because the patent’s control logic depends on comparing the "road load" to this "setpoint" to switch between operating the electric motor and the engine.
  • "abnormal and transient conditions": Based on the patent’s prosecution history, Petitioner proposed construing this phrase as "starting and stopping of the engine and provision of torque to satisfy drivability or safety considerations." This construction was necessary to map prior art teachings to dependent claims reciting this limitation.

5. Key Technical Contentions (Beyond Claim Construction)

  • Torque-Based vs. Speed-Based Control in Severinsky: A central technical argument was that the control strategy in the primary reference, Severinsky, is fundamentally based on torque demand (road load), not vehicle speed. Petitioner contended that while Severinsky used terms like "highway cruising" (engine mode) and "low speed circumstances" (motor mode), these were merely descriptive of typical conditions where certain torque levels are required. The underlying trigger for mode switching, Petitioner argued, was the required torque, aligning it with the ’097 patent’s claims.

6. Relief Requested

  • Petitioner requested that the Board institute an inter partes review and cancel claims 1, 3, 4, 7, 9, 11, 13, 14, 17, 19, 21, 23, 24, 27, 28, 30, 32, 33, 37, and 38 of the ’097 patent as unpatentable.