PTAB

IPR2016-01428

Fluke Corp v. AmeTek Denmark AS

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: THERMAL CALIBRATING SYSTEM
  • Brief Description: The ’742 patent discloses a technique for controlling heat transfer within a temperature calibrating system. The system uses a heat-transfer device, such as a thermosiphon or heat pipe, connected between a cooling unit and a calibration unit, with an attached external chamber used to control the thermal conductivity between the two units.

3. Grounds for Unpatentability

Ground 1: Claims 1-20 are anticipated or obvious over Marcarino, Kögler, and Sone.

  • Prior Art Relied Upon: Marcarino (a 2003 journal article on gas-controlled heat pipes), Kögler (U.K. Patent Application GB 2 003 596 A), and Sone (Application # 2005/0109057).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that independent claim 1 is anticipated by Figure 1 of Marcarino under 35 U.S.C. §102. Marcarino allegedly disclosed a gas-controlled heat pipe system for temperature calibration with all claimed elements, including a heat pipe connecting a "thermometer well" (the calibration unit) and a "water cooling" jacket (the cooling unit), with a "Helium Pressure Line" and its associated ballast tank serving as the external chamber to control thermal conductivity. In the alternative, Petitioner argued for obviousness under 35 U.S.C. §103, contending that if the claims require a "liquid flow modulated" system, a POSITA would find it obvious to modify Marcarino's gas-loaded system with the teachings of Kögler, which explicitly discloses a liquid flow modulated heat pipe with an external chamber. For dependent claims, Petitioner argued Marcarino's furnace met the "electric heating elements" limitation (claim 2), its helium line inherently included a "filler connection" (claim 4), and its "thermometer wells" met the "metal block" limitations (claims 18-20). For claims requiring a Stirling cooler (13-14), Petitioner combined Marcarino with Sone, which explicitly teaches a thermosiphon connected to the "cold head" of a Stirling cooler.
    • Motivation to Combine: A POSITA would combine Marcarino with Kögler to create a simpler, more efficient system, as Kögler's liquid flow modulation eliminates the need for the inert gas and complex pressure controls found in Marcarino's gas-loaded system. Adding an external chamber from Kögler to the open-ended system in Marcarino's Figure 6 was motivated by the desire to prevent the loss of expensive working fluid and expand the device's operating temperature range. The motivation to add Sone's Stirling cooler was to substitute a known, portable, and efficient cooling element for Marcarino's less portable water cooler, a simple design choice to improve the overall system.
    • Expectation of Success: Petitioner asserted that a POSITA would have a high expectation of success, as the proposed combinations involved replacing known functional components (e.g., a gas-control mechanism with a liquid-flow mechanism, a water cooler with a Stirling cooler) with other well-understood components to achieve predictable results.

Ground 2: Claims 1-20 are obvious over Kögler, Bronlund, and Sone.

  • Prior Art Relied Upon: Kögler (U.K. Patent Application GB 2 003 596 A), Bronlund (Patent 6,709,152), and Sone (Application # 2005/0109057).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Kögler discloses a liquid flow modulated heat pipe with an external chamber that controls heat transfer between a heat source and a heat sink, thus teaching every element of claim 1 except for a specific "temperature calibration unit." Bronlund, which is directed to calibrating temperature sensors, allegedly supplied this missing element by teaching a calibration unit comprising an "inner wall" for receiving a temperature sensor. Petitioner contended that incorporating Bronlund's calibration unit into Kögler's controllable heat pipe system would result in the claimed invention. For dependent claims, Bronlund's "heat-regulating unit" was asserted to teach the claimed heating elements (claims 2-3), while Kögler's design inherently provided a filler connection (claim 4) and temperature control for the external chamber (claims 5-6). Sone was again relied upon to supply the Stirling cooler element for claims 13-14.
    • Motivation to Combine: A POSITA would be motivated to adapt Kögler's general-purpose variable conductance heat pipe (VCHP) for the specific, well-known application of temperature calibration by incorporating the dedicated calibration unit from Bronlund. This combination would also be advantageous because using Kögler's internal vapor flow for heat regulation would eliminate the need for Bronlund's complex circulation pumps and piping, resulting in a simpler, more portable, and less expensive calibration device.
    • Expectation of Success: Success in combining the references was argued to be predictable. It was well-known in the art to use the stable internal environment of a VCHP for temperature calibration and to modify heat pipe end caps to insert sensors, making the integration of Bronlund's calibration unit into Kögler's device a routine and predictable design choice.

4. Key Claim Construction Positions

  • "connected between": Petitioner argued this term should be construed to mean that the heat transfer device is disposed so as to transfer heat from the calibration unit to the cooling unit.
  • "external chamber for controlling the thermal conductivity between the two units": Petitioner proposed this phrase be construed as a container operatively associated with a variable conductance heat transfer device, used for adjusting the heat transfer between the calibrator and the cooler.

5. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 1-20 of Patent 8,342,742 as unpatentable.