PTAB

IPR2025-01272

Harbor Freight Tools USA, Inc. v. Champion Power Equipment, Inc.

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1. Case Identification

2. Patent Overview

  • Title: OFF-BOARD FUEL REGULATOR FOR GENERATOR ENGINE
  • Brief Description: The ’985 patent relates to a generator and fuel delivery system using a two-stage fuel regulator located off-board the generator. The system is configured to supply gaseous fuel from a pressurized source to a generator engine, including multi-fuel engines.

3. Grounds for Unpatentability

Ground 1: Anticipation/Obviousness over Parlatore - Claims 1-3 and 11-13 are anticipated or, alternatively, obvious over Parlatore.

  • Prior Art Relied Upon: Parlatore (Application # 2011/0100335).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Parlatore disclosed all limitations of the independent claims. Parlatore taught a fuel delivery system for use with generators that includes an off-board fuel regulator system with a first stage (primary regulator) and a second stage (secondary regulator). This system takes high-pressure gaseous fuel from a pressurized LPG tank, regulates it down to a first reduced pressure in the first stage, and then further regulates it down to a desired lower pressure in the second stage for delivery to the engine's carburetor.
    • Motivation to Combine (for §103 alternative): For any elements not explicitly disclosed for a generator, Petitioner asserted a POSITA would be motivated to use Parlatore's off-board configuration with a generator. Motivations cited from Parlatore itself included the need for longer run times, which requires larger, off-board tanks that are more practical than smaller, on-board tanks. Further motivations included enhanced safety by locating regulators away from the generator's heat and vibration, and reducing the generator's overall size and weight for portability.
    • Expectation of Success: A POSITA would have had a reasonable expectation of success because the off-board two-stage regulator configuration was well-known and commonly used for other propane appliances like BBQ grills. The core function of the fuel delivery system would be identical and predictable regardless of whether it was mounted directly on or remotely from the generator.

Ground 2: Anticipation by the Tri-Fuel Video - Claims 1, 4, 7, 11, 14, 16, and 18 are anticipated by the Tri-Fuel Video.

  • Prior Art Relied Upon: Tri-Fuel Video (a YouTube video posted in 2011).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner contended the Tri-Fuel Video disclosed a complete system meeting all limitations of the challenged claims. The video showed a Honda generator modified to be a dual-fuel system, capable of operating on its original liquid fuel (gasoline) or a gaseous fuel (propane). The gaseous fuel delivery system included two distinct pressure regulators mounted directly to an off-board propane tank. The video explained that these regulators reduce the gas pressure in two successive stages before it is delivered to the generator's modified carburetor through a hose featuring a quick-connect coupling for easy attachment.

Ground 3: Obviousness over Parlatore, DuroMax, and Elsdon - Claims 4-6 and 14-15 are obvious over Parlatore in view of DuroMax and Elsdon.

  • Prior Art Relied Upon: Parlatore (Application # 2011/0100335), DuroMax (DuroMax XP4400EH Operator’s Manual), and Elsdon (Patent 5,718,265).

  • Core Argument for this Ground:

    • Prior Art Mapping: This ground combined Parlatore's off-board regulator system with features from DuroMax and Elsdon to arrive at the claimed dual-fuel system with a "fuel lockout apparatus." Petitioner argued DuroMax disclosed a dual-fuel generator with a mechanical fuel valve for selecting between gasoline and LPG. Elsdon disclosed a retrofittable fuel conduit cap and shield assembly that physically blocked access to a fuel coupler. Combining these would result in a system where turning the DuroMax valve to the gasoline position simultaneously rotates the Elsdon cap to physically block the LPG inlet, thereby "preventing coupling" of the LPG source, as recited in claim 6.
    • Motivation to Combine: A POSITA would be motivated to combine these references to solve the known and critical problem of preventing simultaneous operation on both gasoline and LPG, a safety hazard explicitly warned against in the DuroMax manual. Linking the movement of the DuroMax fuel valve to the Elsdon lockout cap would create a simple, intuitive, and effective engineered safeguard that automatically blocks the unused fuel inlet. Elsdon's express teaching that its cap could be retrofitted onto existing "construction equipment" like generators provided a direct suggestion for the combination.
    • Expectation of Success: The mechanical integration was described as straightforward. A POSITA would understand that a simple rotating valve handle (DuroMax) could be easily connected to a simple rotating cap (Elsdon) to function in unison, providing a high expectation of success for creating a reliable lockout mechanism.

  • Additional Grounds: Petitioner asserted additional challenges, including obviousness of claims 7-10 over Parlatore and the LP-Gas Handbook (to add a quick-connect hose); anticipation of claims 1, 4, 11, 14, and 16 over Chaudhari (Indian Patent No. 207333); and various other obviousness combinations including the Tri-Fuel Video, Parlatore, Chaudhari, LP-Gas Handbook, DuroMax, Elsdon, and Hallberg (Patent 4,492,207) to address different claim dependencies and features.

4. Key Claim Construction Positions

  • Petitioner argued that the term "fuel lockout apparatus" in claim 6 should be construed as a means-plus-function term under 35 U.S.C. §112(f). Petitioner contended the word "apparatus" is a generic, non-structural placeholder, and the claim recites a function (providing fuel lockout) without reciting sufficient structure to perform it. This construction is critical because it limits the claim scope to the corresponding structure disclosed in the ’985 patent—specifically a flange (items 58 and 61) rigidly coupled to the fuel valve handle—and its equivalents.
  • For the terms "prevents...coupling" and "permits...to couple" in claim 6, Petitioner asserted they require physically blocking or allowing the attachment of the fuel source connector to the generator's fuel inlet. This construction is central to the obviousness argument over DuroMax and Elsdon, which teaches a physical barrier. Petitioner based this on the patent's sole disclosure of a flange that physically sweeps over the LPG inlet and the prosecution history of a related patent, distinguishing it from a broader interpretation of merely interrupting fluid flow.

5. Relief Requested

  • Petitioner requested the institution of an inter partes review and the cancellation of claims 1-19 of the ’985 patent as unpatentable.