PTAB

IPR2018-01199

Wirtgen America, Inc. v. Caterpillar Paving Products Inc.

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1. Case Identification

2. Patent Overview

  • Title: System for Saving and Recalling Paving Machine Screed Settings
  • Brief Description: The ’871 patent discloses a paving machine with a system to automate the saving and recalling of configuration parameters for its screed assembly. The system uses a controller, sensors, actuators, and an operator input device to store settings from a first paving operation and automatically adjust the screed to those settings for a subsequent operation.

3. Grounds for Unpatentability

Ground 1: Claims 1-3, 6, 9, 13, 14, and 17 are obvious over Grembowicz and Buschmann.

  • Prior Art Relied Upon: Grembowicz (Patent 5,568,992) and Buschmann (Application # 2012/0010787).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Grembowicz taught a paving machine with all the necessary hardware components: a screed assembly with adjustable components (e.g., extendable screeds), a plurality of actuators (hydraulic cylinders) to adjust them, a plurality of sensors (position sensors) to measure their configuration, and a controller. However, Grembowicz only disclosed manual adjustment. Petitioner asserted that Buschmann taught the missing functionality: a control system for a construction machine that saves and recalls operational settings for functional components, which explicitly include a screed. The combination of Grembowicz’s hardware with Buschmann’s save/recall software concept allegedly rendered the claims obvious.
    • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would combine Buschmann's automation with Grembowicz's paver to solve the well-known problems of time-consuming, labor-intensive, and error-prone manual screed setup. Buschmann provided explicit reasons for this combination, including reducing operator interactions, preventing errors, improving laying quality, and ensuring a uniform work result.
    • Expectation of Success: A POSITA would have a reasonable expectation of success because Grembowicz already provided the necessary controller, memory, sensors, and actuators. Implementing Buschmann's teachings would only require programming the existing controller to store the sensor data and execute recall commands, which was a predictable and well-understood modification.

Ground 2: Claim 5 is obvious over Grembowicz, Buschmann, and Lossow.

  • Prior Art Relied Upon: Grembowicz (Patent 5,568,992), Buschmann (Application # 2012/0010787), and Lossow (Application # 2009/0226255).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground built upon the Grembowicz/Buschmann combination to address claim 5, which adds limitations for a pair of tow arm actuators and sensors to pivot the tow arms. Petitioner argued that while Grembowicz disclosed tow arms, Lossow provided specific details on their automated control. Lossow taught a paver with a pair of actuating cylinders and displacement sensors specifically designed to adjust the height and angle of attack of the tow arms.
    • Motivation to Combine: A POSITA seeking to fully automate the paver in Grembowicz/Buschmann would have been motivated to incorporate Lossow’s teachings. Since controlling the tow arm angle of attack is critical for paving quality, a POSITA would have looked to a reference like Lossow for a known method to automate this specific component.

Ground 3: Claims 8 and 12 are obvious over Grembowicz, Buschmann, and Davin.

  • Prior Art Relied Upon: Grembowicz (Patent 5,568,992), Buschmann (Application # 2012/0010787), and Davin (Patent 3,602,113).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground added Davin to address claims 8 and 12, which recite a screed assembly pivotable about a centerline to create an adjustable crown, along with a dedicated crown position actuator and sensor. Petitioner noted that Grembowicz only described one side of the screed. Davin explicitly taught a screed with two main plates that pivot about a centerline using a "crown-adjusting actuator" and a "crowning sensor" to automatically control the crown profile of the asphalt mat.
    • Motivation to Combine: A POSITA would have been motivated to incorporate Davin’s crown control system into the Grembowicz/Buschmann paver. Automating crown adjustment is desirable for paving roads with varying profiles, and Davin provided a well-known, conventional mechanism for achieving this.

Ground 4: Claims 4, 15, and 16 are obvious over Grembowicz, Buschmann, and Emerson.

  • Prior Art Relied Upon: Grembowicz (Patent 5,568,992), Buschmann (Application # 2012/0010787), and Emerson (Patent 6,019,544).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground added Emerson to address claims 4, 15, and 16, which recite including parameters of a tamper bar drive mechanism in the saved/recalled settings. Emerson disclosed a tamping bar and actuator assembly specifically designed to improve compaction at the vulnerable, unconfined edges of a pavement mat. Emerson taught that its edge-compacting device could be attached directly to a standard screed.
    • Motivation to Combine: A POSITA would have been motivated to add Emerson's edge-directed tamping bar to the Grembowicz/Buschmann paver to solve the known problem of poor edge compaction. The ability to save and recall tamper bar operational parameters (e.g., stroke), as taught by Buschmann, would be a logical extension of automating all key screed functions.

4. Key Claim Construction Positions

  • Petitioner contended that the terms "screed assembly having a plurality of adjustable components" and "the plurality of adjustable components includes the tow arms" were indefinite because a POSITA would not consider tow arms to be part of the screed assembly.
  • For the purposes of the IPR, however, Petitioner proceeded with its obviousness arguments by assuming the terms were definite and construed to include the tow arms as part of the screed assembly.

5. Arguments Regarding Discretionary Denial

  • Petitioner argued against discretionary denial by highlighting that the primary prior art references relied upon in the petition (Grembowicz, Buschmann, Lossow, Davin) were not cited or applied by the USPTO during the original prosecution of the ’871 patent.
  • Petitioner also noted a co-pending ITC Investigation (No. 337-TA-1088) in which an Initial Determination found certain claims invalid under 35 U.S.C. §101, but argued this different legal basis did not preempt the PTAB from instituting trial to consider obviousness under §103 based on new prior art combinations.

6. Relief Requested

  • Petitioner requested the institution of an inter partes review and cancellation of claims 1-6, 8-9, and 12-17 of Patent 9,045,871 as unpatentable.