DCT

2:24-cv-01302

Champion Power Equipment Inc v. Harbor Freight Tools USA Inc

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 2:24-cv-01302, E.D. Wis., 10/14/2024
  • Venue Allegations: Venue is alleged to be proper based on Defendant operating at least twenty-nine regular and established retail store locations within Wisconsin, including in the Eastern District, where the alleged acts of infringement occurred.
  • Core Dispute: Plaintiff alleges that Defendant’s multi-fuel portable generators infringe thirteen patents related to dual-fuel engine technology, including systems for fuel selection, fuel delivery, and safety lockouts.
  • Technical Context: The patents relate to fuel systems for portable generators capable of operating on multiple fuel sources, such as gasoline and propane (LPG), a key feature for reliability and convenience in the consumer and commercial power equipment market.
  • Key Procedural History: The complaint alleges that Plaintiff sent correspondence to Defendant on at least three occasions prior to filing suit, demanding cessation of infringement or a license. This correspondence may be relevant to the allegations of willful infringement.

Case Timeline

Date Event
2015-06-12 Priority Date for ’034, ’120, ’780, ’895, ’398, ’145 Patents
2016-02-04 Priority Date for ’101, ’667, ’390, ’896 Patents
2019-03-05 U.S. Patent No. 10,221,780 Issued
2019-08-27 U.S. Patent No. 10,393,034 Issued
2020-03-24 U.S. Patent No. 10,598,101 Issued
2020-06-30 U.S. Patent No. 10,697,398 Issued
2021-10-12 U.S. Patent No. 11,143,120 Issued
2021-10-12 U.S. Patent No. 11,143,145 Issued
2022-04-19 U.S. Patent No. 11,306,667 Issued
2022-11-08 U.S. Patent No. 11,492,985 Issued
2022-12-20 U.S. Patent No. 11,530,654 Issued
2023-09-19 U.S. Patent No. 11,761,390 Issued
2023-12-12 U.S. Patent No. 11,840,970 Issued
2024-02-20 U.S. Patent No. 11,905,895 Issued
2024-02-20 U.S. Patent No. 11,905,896 Issued
2024-03-27 Plaintiff allegedly sent correspondence to Defendant
2024-05-17 Plaintiff allegedly sent correspondence to Defendant
2024-06-28 Plaintiff allegedly sent correspondence to Defendant
2024-10-14 Complaint Filed

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 10,393,034 - “FUEL SYSTEM FOR A MULTI-FUEL INTERNAL COMBUSTION ENGINE”

The Invention Explained

  • Problem Addressed: The patent describes a problem common to dual-fuel engines where switching between a liquid fuel (like gasoline) and a gaseous fuel (like propane) can lead to simultaneous fuel delivery. This results in an "overly rich air-fuel ratio," which can make the engine hard to start or cause it to run unstably ('034 Patent, col. 2:1-10).
  • The Patented Solution: The invention proposes an electro-mechanical system to manage the fuel paths. It uses a liquid cutoff solenoid to control the flow of liquid fuel from the carburetor's float bowl and a separate gaseous cutoff to control the gaseous fuel source. These are operated by a single switch, allowing an operator to switch between fuels "on-the-fly" while ensuring that only one fuel source is active at a time ('034 Patent, Abstract; col. 3:51-61).
  • Technical Importance: This approach provides a reliable method for fuel switching in portable generators without degrading engine performance, which is a significant usability and safety feature where fuel availability can vary ('034 Patent, col. 2:6-10).

Key Claims at a Glance

  • The complaint asserts independent claims 1, 11, and 18 (Compl. ¶13).
  • Independent Claim 1 includes the following essential elements:
    • A multi-fuel engine operable on a liquid and a gaseous fuel.
    • A carburetor with a float bowl, attached to the engine's intake.
    • A liquid cutoff solenoid coupled to the carburetor to open and close a liquid fuel path downstream from the float bowl.
    • A gaseous cutoff coupled to open and close a gaseous fuel source to the engine.
    • A switch that selectively couples a power source to the liquid cutoff solenoid to open and close the liquid fuel path.
  • The complaint reserves the right to assert dependent claims (Compl. ¶13).

U.S. Patent No. 11,143,120 - “FUEL SYSTEM FOR A MULTI-FUEL INTERNAL COMBUSTION ENGINE”

The Invention Explained

  • Problem Addressed: The patent addresses the same technical challenge as the ’034 Patent: preventing the simultaneous delivery of liquid and gaseous fuels during fuel source switching, which can cause an "overly rich fuel mixture" and unstable engine operation (’120 Patent, col. 2:1-12).
  • The Patented Solution: This invention focuses on a specific carburetor design for multi-fuel engines. It discloses a carburetor with distinct fuel circuits, including a main fuel circuit and an idle fuel circuit. A "carburetor cutoff solenoid" is configured to selectively control liquid fuel flow through both of these circuits, ensuring that when the engine is switched to operate on gaseous fuel, the liquid fuel supply is completely interrupted at the carburetor level (’120 Patent, Abstract; col. 4:1-15).
  • Technical Importance: By integrating the fuel cutoff mechanism directly into the carburetor's primary circuits, the invention offers a potentially more precise and responsive way to manage fuel transitions compared to systems with external valves alone (’120 Patent, col. 2:1-12).

Key Claims at a Glance

  • The complaint asserts independent claims 12 and 18 (Compl. ¶¶ 22-23).
  • Independent Claim 12 includes the following essential elements:
    • A multi-fuel generator and fuel delivery system with a multi-fuel engine.
    • An alternator driven by the engine.
    • A fuel regulator system with a primary pressure regulator (for reducing pressure from the source) and a secondary pressure regulator (for reducing pressure to a desired level for the engine).
    • An electro-mechanical valve system operated by an electrical switch.
  • The complaint reserves the right to assert dependent claims (Compl. ¶¶ 22-23).

U.S. Patent No. 11,492,985 - “OFF-BOARD FUEL REGULATOR FOR GENERATOR ENGINE”

  • Technology Synopsis: The patent describes a fuel delivery system where the fuel regulator for the gaseous fuel (e.g., propane) is located "off-board" the generator itself, typically mounted on the fuel tank. This system uses a two-stage regulation process to reduce the pressure from the pressurized source for delivery to the engine, which can reduce the size and cost of the generator unit (’985 Patent, Abstract; col. 2:17-30).
  • Asserted Claims: Independent claims 1, 11, and 16 (Compl. ¶¶ 32-33).
  • Accused Features: The complaint alleges that Harbor Freight Models 70476 and 70143 are dual-fuel generators that operate with an off-board, two-stage fuel regulator system for the gaseous fuel source (Compl. ¶¶ 32a, 33a, 33e, 33h).

U.S. Patent No. 11,530,654 - “OFF-BOARD FUEL REGULATOR FOR GENERATOR ENGINE”

  • Technology Synopsis: This patent relates to a dual-fuel generator system with an off-board fuel regulator and adds a "fuel lockout apparatus." This mechanical safety feature is coupled to the fuel selection valve and is configured to physically prevent the gaseous fuel line from being connected while the liquid fuel line is open, and vice-versa, thereby preventing simultaneous fuel flow (’654 Patent, Abstract).
  • Asserted Claims: Independent claims 6 and 10 (Compl. ¶¶ 42-43).
  • Accused Features: The complaint accuses Harbor Freight Models 70476 and 70143 of using a dual-fuel system that includes a mechanical fuel valve with an integrated fuel lockout apparatus that prevents the coupling of one fuel source while the other is active (Compl. ¶¶ 42a, 43a, 43b).

U.S. Patent No. 11,840,970 - “DUAL FUEL GENERATOR WITH REMOTE REGULATOR”

  • Technology Synopsis: This patent describes a dual-fuel generator system that combines an off-board ("remote") two-stage fuel regulator with a mechanical fuel valve for selecting between liquid and gaseous fuel. The invention specifies a generator that is "free of any pressure regulator mounted within the generator housing," emphasizing the remote nature of the regulation system (’970 Patent, Abstract; col. 2:37-49).
  • Asserted Claims: Independent claims 1, 12, 20, 34, and 44 (Compl. ¶¶ 52-53).
  • Accused Features: The complaint alleges the accused generators utilize an off-board fuel regulator system and a mechanical fuel valve to control fuel flow, and that the generator units themselves are free of any gas pressure regulators (Compl. ¶¶ 52a, 52c, 53a, 53c, 53f, 53h, 53i).

U.S. Patent No. 10,221,780 - “DUAL FUEL LOCKOUT SWITCH FOR GENERATOR ENGINE”

  • Technology Synopsis: The patent discloses a "mechanical fuel lockout switch" for a dual-fuel engine. The invention comprises a mechanical fuel valve linked to a "fuel lockout apparatus" that physically prevents the connection of a second fuel source while a first is active, ensuring that the two fuels cannot be delivered simultaneously (’780 Patent, Abstract). The switch communicates the selected fuel source to the engine while interrupting the other.
  • Asserted Claims: Independent claims 1, 8, and 15 (Compl. ¶62).
  • Accused Features: The complaint alleges the Harbor Freight Model 70143 infringes by incorporating a mechanical fuel lockout switch with a fuel valve and a lockout apparatus that prevents coupling of the second fuel source while the first is in use (Compl. ¶62a, 62c, 62d).

U.S. Patent No. 11,905,895 - “DUAL FUEL LOCKOUT SWITCH FOR GENERATOR ENGINE”

  • Technology Synopsis: This patent is a continuation of the technology in the '780 patent, further detailing a mechanical fuel lockout switch. The claims describe a mechanical valve configured to allow communication with a first fuel source while preventing it with a second, and a coupled lockout apparatus that physically prevents the second fuel source from being coupled to its fuel line while the first is active (’895 Patent, Abstract).
  • Asserted Claims: Independent claims 1 and 8 (Compl. ¶71).
  • Accused Features: The complaint alleges both accused models contain a mechanical fuel lockout switch with a fuel valve and a coupled lockout apparatus that prevents simultaneous fuel delivery by controlling which fuel line can be physically coupled (Compl. ¶71a, 71d).

U.S. Patent No. 10,697,398 - “BATTERYLESS DUAL FUEL ENGINE WITH LIQUID FUEL CUT-OFF”

  • Technology Synopsis: This invention describes a dual-fuel engine that does not require a battery for its fuel-switching operation. It incorporates a liquid fuel cut-off into the carburetor that is powered by an electrical generator on the engine (e.g., a magneto or alternator). This allows a pull-start engine to power the solenoid that interrupts liquid fuel flow when switching to gaseous fuel (’398 Patent, Abstract).
  • Asserted Claims: Independent claims 1 and 57 (Compl. ¶¶ 80-81).
  • Accused Features: The accused generators are alleged to be dual-fuel engines with a fuel cut-off in the carburetor that is actuated by a switch and powered by the engine's own electrical generator, enabling batteryless operation (Compl. ¶¶ 80a, 81a, 81e).

U.S. Patent No. 11,143,145 - “BATTERYLESS DUAL FUEL ENGINE WITH LIQUID FUEL CUT-OFF”

  • Technology Synopsis: This patent builds on the '398 patent, further detailing a batteryless dual-fuel generator. It specifies a "charging coil" as part of the electrical power generator and a "voltage regulator" that provides regulated voltage from the coil to the liquid fuel cut-off solenoid. This ensures the solenoid receives the correct power for operation without a battery (’145 Patent, Abstract).
  • Asserted Claims: Independent claims 1 and 11 (Compl. ¶¶ 90-91).
  • Accused Features: The accused generators are alleged to have a batteryless dual-fuel system that uses a charging coil and a voltage regulator to power a liquid fuel cut-off solenoid, as well as a manually actuated fuel shutoff (Compl. ¶¶ 90a, 91a).

U.S. Patent No. 10,598,101 - “DUAL FUEL SELECTOR SWITCH”

  • Technology Synopsis: This patent describes a "dual fuel selector switch" that includes a valve assembly with two separate mechanical fuel valves. A user operates a single selector switch or handle that is mechanically coupled to both valves, ensuring that when one fuel valve is opened, the other is closed, thereby preventing concurrent fuel flow (’101 Patent, Abstract). The invention covers both manual and solenoid-based selector configurations.
  • Asserted Claims: Independent claims 1, 10, 17, and 18 (Compl. ¶¶ 100-101).
  • Accused Features: The accused generators are alleged to include a fuel selector with a valve assembly and a manual selector switch that controls separate mechanical valves for each fuel source (Compl. ¶¶ 100a, 100e, 100g, 100h, 101a, 101e, 101g).

U.S. Patent No. 11,306,667 - “DUAL FUEL SELECTOR SWITCH”

  • Technology Synopsis: This patent further develops the fuel selector switch concept from the '101 patent. It details a selector with a valve assembly having two fuel inputs and two fuel outputs, where a selector switch manually controls which fuel flows. It also describes configurations where the switch actuates a carburetor solenoid when one of the fuel modes is selected (’667 Patent, Abstract).
  • Asserted Claims: Independent claims 1 and 10 (Compl. ¶¶ 110-111).
  • Accused Features: The accused generators are alleged to use a fuel selector with a valve assembly having two inputs/outputs and a manual switch, including a version that actuates a carburetor solenoid (Compl. ¶¶ 110a, 110j, 111a).

U.S. Patent No. 11,761,390 - “DUAL FUEL SELECTOR SWITCH”

  • Technology Synopsis: This patent focuses on a selector switch with distinct "fuel modes." The switch controls a fuel solenoid and a solenoid switch. When the selector switch is moved from one mode to another (e.g., gasoline to LPG), it triggers the solenoid switch, which in turn causes the fuel solenoid to open or close, enabling the selection of one fuel flow while disabling the other (’390 Patent, Abstract).
  • Asserted Claims: Independent claim 1 (Compl. ¶120).
  • Accused Features: The Harbor Freight Model 70476 is accused of having a selector switch with distinct fuel modes that control a fuel solenoid and a solenoid switch to manage fuel flow (Compl. ¶120a).

U.S. Patent No. 11,905,896 - “DUAL FUEL SELECTOR SWITCH”

  • Technology Synopsis: This patent describes a fuel selector with a valve assembly that is "fluidly couplable" to two fuel sources. The assembly includes two fuel inputs and two fuel outputs, and a selector switch allows a user to manually select which fuel flows to the engine. The claims specify that the fuel valves are "non-solenoid, mechanical valves" (’896 Patent, Abstract).
  • Asserted Claims: Independent claim 30 (Compl. ¶¶ 129-130).
  • Accused Features: Both accused models are alleged to use a fuel selector with a valve assembly, two inputs/outputs, and a manual selector switch controlling non-solenoid, mechanical valves (Compl. ¶¶ 129a, 130a).

III. The Accused Instrumentality

Product Identification

  • The complaint identifies the Harbor Freight Model 70476 and Harbor Freight Model 70143 multi-fuel portable generators (Compl. ¶¶ 21, 31).

Functionality and Market Context

  • The complaint alleges these products are multi-fuel portable generators that can operate on both a liquid fuel (gasoline) and a gaseous fuel (LPG) (Compl. ¶¶ 13a, 13d, 21a). The core accused functionality is the generators' complete fuel delivery system, including the mechanisms for selecting between fuel sources, regulating fuel pressure, and preventing the simultaneous flow of both fuels to the engine (Compl. ¶¶ 13, 22, 32, 42, 52, 62, 71, 80, 90, 100, 110, 120, 129). The complaint asserts these products are made, used, sold, or offered for sale within the United States (Compl. ¶12). No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

’034 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
a multi-fuel engine comprising an engine operable on a liquid fuel and a gaseous fuel; The accused Model 70476 is a multi-fuel generator with an engine that operates on liquid and gaseous fuel. ¶13a col. 3:51-53
a carburetor attached to an intake of the engine to mix air and fuel and connect a liquid fuel source to the intake, the carburetor comprising a float bowl; The accused product has a carburetor with a float bowl attached to the engine intake. ¶13a col. 3:54-57
a liquid cutoff solenoid coupled to the carburetor to open and close a liquid fuel path to the engine downstream from the float bowl; The accused product includes a liquid cutoff solenoid connected to the carburetor that controls the liquid fuel path after the float bowl. ¶13a col. 3:58-61
a gaseous cutoff coupled to open and close a gaseous fuel source to the engine; The accused product has a gaseous cutoff mechanism to control the flow of gaseous fuel. ¶13a col. 3:62-64
and a switch selectively coupling a power source to the liquid cutoff solenoid to open and close the liquid fuel path... The accused product utilizes a switch that selectively powers the liquid cutoff solenoid to manage the liquid fuel path. ¶13a col. 3:65-67

Identified Points of Contention

  • Technical Questions: The complaint's allegations are presented at a high level. A key question will be one of operational mapping: does the accused product’s system of valves and switches function in the specific manner claimed? For example, what evidence demonstrates that the accused "gaseous cutoff" and "liquid cutoff solenoid" are distinct components that operate under the control of the switch as recited in the claim, rather than a single mechanical valve performing multiple functions?
  • Scope Questions: The analysis may turn on the construction of "selectively coupling." A question for the court may be whether the accused switch performs this specific electrical function or if it operates through a different mechanical or electro-mechanical principle that falls outside the claim's scope.

’120 Patent Infringement Allegations

Claim Element (from Independent Claim 12) Alleged Infringing Functionality Complaint Citation Patent Citation
a multi-fuel generator and fuel delivery system having a multi-fuel internal combustion engine configured to operate on a liquid fuel...and a gaseous fuel... The accused Models 70476 and 70143 are multi-fuel generators with engines configured to operate on liquid and gaseous fuels. ¶22a; ¶23a col. 8:14-20
an alternator driven by the multi-fuel internal combustion engine, The accused generators include an alternator driven by the engine. ¶22a; ¶23a col. 8:21-22
and a fuel regulator system including a primary pressure regulator...to regulate fuel...to a reduced pressure and a secondary pressure regulator...to regulate fuel...to a desired pressure... The accused products utilize a fuel regulator system with both primary and secondary pressure regulators to manage gaseous fuel pressure in two stages. ¶22a; ¶23a col. 8:23-33
an electro-mechanical valve system coupled to the engine and operated by an electrical switch...that controls fuel flow to the engine from the liquid fuel source and the pressurized fuel source... The accused products have an electro-mechanical valve system and an electrical switch to control flow from both fuel sources. ¶22b; ¶23a col. 8:34-40

Identified Points of Contention

  • Technical Questions: A primary factual dispute may focus on the regulator architecture. What evidence does the complaint provide that the accused products' regulator is a two-stage system with distinct "primary" and "secondary" regulators as claimed, rather than a single-stage regulator or a functionally different multi-stage design?
  • Scope Questions: The term "electro-mechanical valve system" is broad. Its construction will be critical. A question for the court will be whether this term, in the context of the patent, is limited to the specific solenoid-based systems shown in the embodiments or if it can be construed more broadly to cover other types of valve systems that might be present in the accused products.

V. Key Claim Terms for Construction

For the ’034 Patent

  • The Term: "liquid cutoff solenoid"
  • Context and Importance: This term is central to how the invention controls the liquid fuel path. Practitioners may focus on this term because the infringement allegation depends on the accused product having a component that is structurally and functionally a "solenoid" dedicated to cutting off liquid fuel, as distinct from a multi-function mechanical valve.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The specification describes the function as being "advantageous to control liquid fuel flow downstream of a float bowl" (’034 Patent, col. 7:5-7), which might support interpreting the term functionally to cover any electrically-actuated valve that performs this role.
    • Evidence for a Narrower Interpretation: The figures and detailed description consistently depict the "liquid cutoff solenoid" (96) as a specific component coupled to the carburetor (86) (’034 Patent, Fig. 2; col. 5:44-55). This may support a narrower construction tied to the disclosed embodiment.

For the ’120 Patent

  • The Term: "fuel regulator system including a primary pressure regulator...and a secondary pressure regulator"
  • Context and Importance: The claim requires a specific two-part architecture for regulating gaseous fuel pressure. Infringement hinges on the accused system matching this structure. The defendant may argue its system uses a single, integrated regulator or a different architecture that does not meet this limitation.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The patent describes the general purpose as protecting "downstream components from high pressure" and delivering fuel "at a desired pressure" (’120 Patent, col. 4:20-25). This functional language could support a reading on any system that performs these two pressure-reduction steps, regardless of physical form.
    • Evidence for a Narrower Interpretation: The specification explicitly describes the "primary pressure regulator 64" and "secondary pressure regulator 66" as distinct components, noting that "typically, the primary pressure regulator is mounted on the LPG tank, while the secondary pressure regulator is mounted on the component using the fuel" (’120 Patent, col. 4:30-34). This suggests a construction requiring two separate, physically distinct regulators.

VI. Other Allegations

  • Indirect Infringement: The complaint does not plead specific facts to support claims of induced or contributory infringement, focusing instead on direct infringement by making, using, selling, and offering for sale the accused products (Compl. ¶12).
  • Willful Infringement: Willfulness is alleged for all asserted patents (Compl. ¶¶ 15, 25, 35, 45, etc.). The basis for these allegations is alleged pre-suit knowledge of Champion's patent rights, stemming from correspondence sent to Harbor Freight on March 27, 2024, May 17, 2024, and June 28, 2024 (Compl. ¶¶ 16, 26, 36, 46, etc.).

VII. Analyst’s Conclusion: Key Questions for the Case

  • A central technical question will be one of architectural correspondence: do the accused generators' fuel selection and regulation systems, as a whole, map onto the specific multi-solenoid, batteryless power, lockout switch, and two-stage regulator configurations required by the various asserted independent claims, or are there fundamental operational and structural differences?
  • A key legal question will concern claim construction: how broadly will terms such as "fuel lockout apparatus," "electro-mechanical valve system," and "fuel regulator system" be defined? The resolution will determine whether the accused products' components, which may achieve a similar outcome of safe fuel switching, do so using the specific structures recited in the patents.
  • Given the large number of asserted patents and allegations of pre-suit notice via multiple letters, a significant issue will be damages and willfulness: should infringement be found on any claim, the dispute will likely involve complex damages calculations, and the court will need to assess whether Harbor Freight's alleged conduct after receiving notice rises to the level of willful infringement justifying enhanced damages.