DCT
0:18-cv-01553
Thermo King Corp v. Rigmaster Power Intl Ltd
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Thermo King Corporation (Delaware)
- Defendant: Rigmaster Power International Ltd. (Canada)
- Plaintiff’s Counsel: Robins Kaplan LLP
- Case Identification: 0:18-cv-01553, D. Minn., 06/05/2018
- Venue Allegations: Plaintiff alleges venue is proper in the District of Minnesota because Defendant transacts business in the state, including through approximately eight local dealerships, and places infringing products into the stream of commerce knowing they would be sold in the district.
- Core Dispute: Plaintiff alleges that Defendant’s auxiliary power unit (APU) systems for trucks infringe a patent related to integrated control systems for such units.
- Technical Context: The technology concerns control systems for APUs, which provide climate control and power to a truck's cabin when its primary engine is off, thereby reducing fuel consumption, emissions, and engine wear associated with idling.
- Key Procedural History: The complaint does not mention any prior litigation, post-grant proceedings, or licensing history related to the patent-in-suit. The patent claims priority to a 2005 provisional application.
Case Timeline
| Date | Event |
|---|---|
| 2005-01-21 | '018 Patent Priority Date |
| 2015-06-02 | '018 Patent Issue Date |
| 2018-06-05 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 9,045,018 - "Control System for Auxiliary Power Unit"
The Invention Explained
- Problem Addressed: The patent’s background section describes that vehicle functions like air conditioning, heating, and engine warming are typically controlled by separate systems, which can be costly, bulky, and cumbersome to install and operate when used with an auxiliary power unit (APU) (’018 Patent, col. 1:21-28).
- The Patented Solution: The invention is a unified control system for a vehicle's APU. It uses a single microprocessor that communicates with the vehicle's primary engine, its cabin, and the APU. When the main truck engine is shut down, the microprocessor can selectively activate the APU to manage both "engine parameters" (e.g., maintaining battery voltage) and "cabin parameters" (e.g., maintaining a set temperature), integrating these functions into one system (’018 Patent, Abstract; col. 2:41-47).
- Technical Importance: This integrated control system aims to efficiently manage vehicle functions during rest periods, reducing the fuel consumption, maintenance costs, and emissions that result from idling the primary engine (’018 Patent, col. 1:12-16).
Key Claims at a Glance
- The complaint asserts infringement of at least independent claim 1 (Compl. ¶16).
- The essential elements of independent claim 1 are:
- A control system for a vehicle that includes a cabin and a primary engine having an ignition switch, the control system comprising:
- an auxiliary power unit coupled to the primary engine and including a secondary engine; and
- a microprocessor in communication with the primary engine and the cabin and operable to activate the auxiliary power unit and to control an engine parameter and a cabin parameter when the primary engine is shutdown.
- The complaint’s use of "one or more claims, including at least claim 1" suggests the right to assert additional claims is reserved (Compl. ¶16).
III. The Accused Instrumentality
Product Identification
- The complaint names the "MTS-T46K APU system" and "any same or similar products" manufactured and sold by Defendant Rigmaster (Compl. ¶16).
Functionality and Market Context
- The accused product is described as a "stand-alone truck-mounted APU" that provides power for climate control and battery charging when the main engine is off (Compl. ¶¶ 18-20). The complaint cites Defendant's marketing materials stating the APU "runs all night on what your idling truck engine burns in two hours," positioning it as a fuel-saving device (Compl. p. 9).
- The system includes a "microprocessor controller located inside the cab" which provides "one-touch stop/start and climate control," "engine monitoring," and "adjustable voltage battery monitoring" (Compl. ¶19; Compl. p. 8). A screenshot from the accused product's marketing materials lists features of the in-cab controller (Compl. p. 8).
- The complaint alleges the system functions when the primary engine is shut down to control cabin temperature and to automatically start the APU to charge the truck battery if the voltage gets low (Compl. ¶¶ 20, p. 10).
IV. Analysis of Infringement Allegations
U.S. Patent No. 9,045,018
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a control system for a vehicle that includes a cabin and a primary engine having an ignition switch... | The MTS-T46K APU system is designed for installation on a vehicle with a cabin and a primary engine, which includes an ignition switch. | ¶17 | col. 1:9-11 |
| an auxiliary power unit coupled to the primary engine and including a secondary engine; | The accused system is an APU with its own secondary engine (a "2 CYL...Kohler" engine) and is coupled to the primary engine's systems through shared fuel and battery supplies. A marketing image shows the self-contained engine (Compl. p. 7). | ¶18 | col. 3:6-10 |
| a microprocessor in communication with the primary engine and the cabin... | The system's "microprocessor controller" is located in the cabin and performs "engine monitoring" (e.g., coolant level, battery voltage) and cabin "climate control," establishing the alleged communication. A diagram shows the controller mounted inside the cab (Compl. p. 6). | ¶19 | col. 4:26-28; col. 4:51-53 |
| and operable to activate the auxiliary power unit and to control an engine parameter and a cabin parameter when the primary engine is shutdown. | The controller activates the APU (via "Engine Start" button) and controls cabin temperature. It also controls an engine parameter (battery voltage) via an "AutoStart Feature" that starts the APU to charge a low battery. These functions operate when the primary engine is off. | ¶20 | col. 2:43-47 |
Identified Points of Contention
- Scope Questions: The complaint alleges the "coupled to the primary engine" limitation is met by shared fuel and battery supplies (Compl. ¶18). The patent specification, however, also describes a shared coolant system as a means of coupling (’018 Patent, col. 3:20-24). This raises the question of whether the claimed "coupling" requires a thermal connection in addition to the alleged fuel and electrical connections.
- Technical Questions: The infringement theory for "control an engine parameter" rests on the accused product's "AutoStart Feature" for maintaining battery voltage (Compl. p. 10). A central question may be whether maintaining the charge of a vehicle's battery constitutes "control[ling] an engine parameter" as the term is used in the patent, or if it is considered a parameter of the broader vehicle electrical system.
V. Key Claim Terms for Construction
"coupled to the primary engine"
- Context and Importance: The validity of the infringement allegation depends on whether the accused APU's connection to the truck's fuel and battery systems satisfies this limitation. Practitioners may focus on this term because its definition could either include or exclude the specific implementation alleged in the complaint.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: Claim 1 uses the general term "coupled" without specifying the type of connection. The patent describes multiple forms of interaction, including being "in fluid communication with a coolant system" and a "fuel system" (’018 Patent, col. 3:20-27), which could support an interpretation where any one of these connections, including fuel or electrical, is sufficient.
- Evidence for a Narrower Interpretation: The specification highlights the benefit of warming the primary engine via a shared coolant system (’018 Patent, col. 2:35-37). A party could argue that "coupled" in this context implies a functional, thermal coupling that is central to one of the invention's stated purposes, and not merely sharing a fuel tank or battery connection.
"control an engine parameter"
- Context and Importance: This term is critical because the complaint's primary example of controlling an engine parameter is managing battery voltage (Compl. ¶20, p. 10). The case may turn on whether "battery voltage" is legally considered a parameter of the "engine."
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent specification explicitly lists "battery voltage" as an example of a "primary engine parameter" (’018 Patent, col. 4:48). Furthermore, dependent claim 10 recites a microprocessor "operable in response to the battery voltage to selectively activate the auxiliary power unit to vary the battery voltage," directly linking battery voltage control to the invention.
- Evidence for a Narrower Interpretation: The patent's background focuses on solving problems related to the "tractor engine" itself, such as fuel consumption and wear from idling (’018 Patent, col. 1:12-16). A party might argue that "engine parameter" should be construed to mean parameters intrinsic to the mechanical operation of the combustion engine block (e.g., temperature, oil pressure), as distinct from the vehicle's electrical system.
VI. Other Allegations
- Indirect Infringement: The complaint alleges induced infringement, stating that Defendant provides materials such as "owner's manuals, installation manuals, [and] marketing brochures" that instruct and encourage dealers and customers to install and use the accused APU systems in an infringing manner (Compl. ¶21). The complaint also makes a parallel allegation of contributory infringement (Compl. ¶23).
- Willful Infringement: Willfulness is alleged based on Defendant having knowledge of the ’018 patent "at least by the time of the filing and service of the Complaint" and continuing its allegedly infringing conduct thereafter (Compl. ¶27).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of definitional scope: can the term "coupled to the primary engine," which in the patent's specification includes a shared thermal (coolant) system, be construed to cover an APU that is allegedly connected only by its fuel and electrical systems?
- A second central question will be functional and semantic: does the accused product's automatic charging of the vehicle's battery constitute "control[ling] an engine parameter" as required by Claim 1? The resolution will depend on whether "battery voltage" is determined to be a parameter of the "primary engine" itself or of the broader vehicle.
- The case may also present an evidentiary question regarding the claim limitation of a "microprocessor in communication with the primary engine." The parties will likely dispute whether the alleged monitoring of system levels like battery voltage and coolant meets the technical and legal standard for "communication" with the engine as contemplated by the patent.