PTAB

IPR2018-00155

Caterpillar Inc v. Wirtgen America Inc

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Auxiliary Drive
  • Brief Description: The ’628 patent relates to an auxiliary drive system for construction machines that treat ground surfaces, such as cold planers or road milling machines. The invention describes an auxiliary drive that can be selectively engaged to rotate the machine's work drum at a slow speed for maintenance and disengaged during normal high-speed milling operations, which are powered by the machine’s main engine.

3. Grounds for Unpatentability

Ground 1: Obviousness of Method Claims over Caterpillar Manuals - Claims 21 and 27-29 are obvious over Operation Manual in view of Parts Manual.

  • Prior Art Relied Upon: Operation Manual (CAT PM-565 Operation & Maintenance Manual No. KEBU6664-02) and Parts Manual (CAT PM-565 Parts Manual No. KEBP0105-01).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that the combination of the Operation Manual and Parts Manual, which both describe the commercially available Caterpillar PM-565 road milling machine, discloses every element of the challenged method claims. The manuals collectively teach a method of manufacturing a construction machine comprising the steps of providing a machine frame and mounting a work drum, a work motor, and a transmission. This transmission includes a belt drive and a reduction gear. The manuals further disclose mounting a removable auxiliary drive that operably engages the transmission to rotate the work drum at a slow speed for maintenance when the drum is raised.
    • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would combine the Operation Manual and the Parts Manual because they describe the exact same machine. The petition asserted that a POSITA would naturally consult both documents to gain a complete understanding of the PM-565 machine, as the Parts Manual provides detailed schematics that clarify the systems described in the Operation Manual.
    • Expectation of Success: Expectation of success was inherent, as the combination of references described a single, existing, and operational machine.

Ground 2: Obviousness of Apparatus Claims over Manuals and Permanently Mounted Drive References - Claims 1-2, 5-6, 9-20, and 22 are obvious over Operation Manual and Parts Manual in view of Smith or Neuper.

  • Prior Art Relied Upon: Operation Manual, Parts Manual, Smith (UK Patent No. GB 2060794), and Neuper (UK Publication No. GB2208237A).
  • Core Argument for this Ground:
    • Prior Art Mapping: The petition contended that the combination of the Operation Manual and Parts Manual teaches every element of the challenged apparatus claims except for an auxiliary drive that remains mounted at its operational location during both maintenance and primary milling operations. The PM-565 machine described in the manuals utilizes a removable auxiliary drive that must be manually installed for maintenance and removed for milling. Smith and Neuper were introduced to supply the missing element of a permanently mounted, selectively engageable auxiliary drive. Smith discloses a mineral mining machine with a gearbox that allows switching between a main motor and a permanently mounted auxiliary motor. Neuper discloses a roadway machine using an overrunning or switchable clutch to selectively couple a permanently mounted auxiliary motor to the driveline.
    • Motivation to Combine: A POSITA would combine the teachings of Smith or Neuper with the PM-565 machine to solve a known and significant problem: operational downtime. The process of manually attaching and detaching the auxiliary drive and its hydraulic lines for each tool change is inefficient. Petitioner argued that Smith and Neuper teach the clear benefits of a permanently mounted system, including increased operational efficiency, reduced labor, and simplified maintenance. Modifying the PM-565 machine with such a system would have been an obvious improvement to reduce downtime.
    • Expectation of Success: A POSITA would have a high expectation of success. The technologies for selectively engaging a secondary motor, such as the gearboxes in Smith and the clutches in Neuper, were well-known and their application to solve the problem of swapping a removable drive was straightforward and predictable.

4. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 1-2, 5-6, 9-22, and 27-29 of the ’628 patent as unpatentable under 35 U.S.C. §103.