PTAB

IPR2022-00698

Belimo Automation AG v. BelParts Group NV

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Method for Operating and Controlling Flow Control Systems
  • Brief Description: The ’257 patent discloses methods for controlling fluid flow in systems like central heating/cooling (HVAC), using a flow sensor, a control system, and an orifice adjusting system. The purported novelty centers on performing a real-time, "software-wise correction of a characteristic curve" of the orifice adjusting system to compensate for pressure variations.

3. Grounds for Unpatentability

Ground 1: Obviousness over McIntosh in view of Tsuyoshi - Claims 1, 2, 5-9, and 19 are obvious over McIntosh in view of Tsuyoshi.

  • Prior Art Relied Upon: McIntosh (International Publication No. WO 98/25086) and Tsuyoshi (Japanese Publication No. JPH05202901A).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner asserted that McIntosh, a primary reference from prosecution, discloses a modulating fluid control device for HVAC systems that meets nearly all limitations of the independent claims. McIntosh teaches a system with a flow sensor, a programmable controller, and an adjustable valve (orifice adjusting system) that maintains a set flow rate. Petitioner argued the Examiner only allowed the claims after the applicant distinguished McIntosh based on the "direct comparison" and "software-wise correction" limitations. However, Tsuyoshi, which was not before the Examiner, explicitly teaches a control valve system that performs a software-based correction of a valve’s characteristic curve to improve accuracy. Tsuyoshi's system calculates a new correction curve based on measured flow rate and valve opening signals to precisely control the valve.
    • Motivation to Combine: A POSITA would combine Tsuyoshi's software-based curve correction algorithm with McIntosh's well-known HVAC control system to improve its accuracy and precision. The motivation was to better compensate for pressure variations and other system disturbances, which was a known challenge in the art, thereby achieving more stable and efficient process control.
    • Expectation of Success: A POSITA would have had a high expectation of success because both references describe similar fluid flow control systems. Integrating Tsuyoshi's software-based control logic into McIntosh's hardware architecture was a predictable combination of known elements to achieve the expected benefit of improved control loop performance.

Ground 2: Obviousness over Erdmann in view of Forshey - Claims 1, 2, 4, 5, 7, 9, 10, and 19 are obvious over Erdmann in view of Forshey.

  • Prior Art Relied Upon: Erdmann (German Publication No. DE 4019503A1) and Forshey (Application # 2005/0150552).

  • Core Argument for this Ground:

    • Prior Art Mapping: Petitioner presented this as an alternative ground where the primary reference, Erdmann, already discloses the key "software-wise correction" limitation. Erdmann teaches an HVAC system with control devices that actuate valves based on stored characteristic curves and corrects these curves in real-time to account for changing hydraulic conditions. Petitioner argued that while Erdmann does not expressly disclose a flow sensor, one is inherent in its operation. Forshey was introduced to explicitly supply the missing elements. Forshey teaches a pressure-independent flow control system that uses a flow sensor to measure actual flow, directly compares it to a set flow, and generates a control signal to adjust a valve, thus providing a clear feedback loop.
    • Motivation to Combine: A POSITA would combine Forshey's explicit flow sensor and direct comparison logic into Erdmann's system. The motivation was to incorporate a well-known method for providing direct and accurate flow rate feedback, which would improve Erdmann's ability to track the desired flow rate and compensate for system disturbances more effectively than relying on inferred conditions alone.
    • Expectation of Success: A POSITA would expect success because the combination involved adding a standard, familiar feedback control element (Forshey's sensor and comparison loop) into a known type of control system (Erdmann) to yield the predictable result of improved control accuracy.

  • Additional Grounds: Petitioner asserted numerous additional obviousness challenges. These included adding Shen (Chinese Publication No. CN 1837996A) to the McIntosh/Tsuyoshi combination to teach setting a maximum flow rate (Vmax) for claims 3 and 10-18. Other grounds replaced Tsuyoshi with Elshafei (Application # 2009/0240376) as an alternative reference for software-wise curve correction. Further grounds combined Erdmann with Forshey and other references like McIntosh and Shen to meet limitations in claims 3, 6, 8, and 11-18.

4. Key Claim Construction Positions

  • "software-wise correction of the characteristic curve": Petitioner argued this term should be construed to mean "a software-based correction of the characteristic curve to a different software-based characteristic curve." This construction is critical because it requires the underlying control algorithm itself to be modified in software, as taught by references like Tsuyoshi and Erdmann, rather than merely using software to calculate a flow adjustment based on a static curve.
  • "orifice adjusting system": Petitioner proposed this term means "an adjustable valve and an actuator that adjusts the valve opening to regulate the flow." This construction provides a clear basis for mapping the physical components described in the prior art, such as valves and motors, to the claimed system.
  • "real-time": Petitioner argued this term should be understood by its general meaning of "during operation of the flow control system." This interpretation supports the argument that the prior art systems, which perform corrections continuously during operation, meet the limitation.

5. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 1-19 of the ’257 patent as unpatentable.