PTAB

IPR2018-00155

Caterpillar Inc. v. Wirtgen America, Inc.

Log In

1. Case Identification

2. Patent Overview

  • Title: Auxiliary Drive
  • Brief Description: The ’628 patent discloses an auxiliary drive for a cold milling machine (or "cold planer"). The system is designed to allow a small, secondary motor (the auxiliary drive) to slowly rotate the main work drum for maintenance, such as replacing worn cutting bits, while being disengaged during normal high-speed milling operations 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 the combination of Operation Manual and 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 describe Caterpillar’s own prior art PM-565 cold planer, discloses a machine with all the features recited in the steps of independent method claim 21. Specifically, the manuals taught a construction machine for treating ground surfaces comprising a machine frame, a work drum mounted on the frame, and a work motor connected to the drum via a transmission. This transmission included a belt drive (with motor-side and drum-side pulleys) and a reduction gear. The manuals also disclosed mounting a removable auxiliary drive that engaged the transmission to rotate the work drum at a slow speed for maintenance when the drum was raised.
    • Motivation to Combine: Petitioner contended that a person of ordinary skill in the art (POSITA) would have been motivated to combine the teachings of the Operation and Parts Manuals because they describe the exact same machine, with the Parts Manual providing more detailed diagrams of components mentioned in the Operation Manual. The combination was already physically embodied in the PM-565 machine.
    • Key Aspects: Petitioner asserted that if the apparatus (the PM-565 machine) was obvious from the prior art, then the claimed method of manufacturing that same apparatus by simply providing, mounting, and connecting its known components would also have been obvious.

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

  • Prior Art Relied Upon: Operation Manual, Parts Manual, Smith (UK Patent No. GB 2060794), and Neuper (U.K. Publication No. GB2208237A).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner established the combination of the Operation Manual and Parts Manual as teaching all elements of independent apparatus claim 1 except for the limitation requiring the auxiliary drive to have a "second configuration in which the auxiliary drive remains mounted... and the work drum can be rotated by the work motor." The PM-565 machine described in the manuals used an auxiliary drive that was physically removed from its service location and returned to a storage location after maintenance. Petitioner argued that Smith and Neuper both teach the missing element. Smith discloses a mineral mining machine with a secondary hydraulic motor that remains mounted at all times and is selectively engaged or disengaged from the main driveline via a clutch. Neuper discloses a roadway machine with a similar fixed auxiliary motor that uses a switchable or overrunning clutch to engage for slow rotation or disengage for main motor operation.
    • Motivation to Combine: A POSITA would have been motivated to modify the removable auxiliary drive of the PM-565 machine to a permanently mounted one as taught by Smith or Neuper to achieve obvious benefits. The primary motivation was to reduce machine downtime and increase operational efficiency by eliminating the time-consuming steps of physically installing, connecting, disconnecting, and storing the auxiliary drive and its hydraulic lines for each maintenance cycle.
    • Expectation of Success: A POSITA would have had a high expectation of success because Smith and Neuper demonstrated that selectively-clutched, permanently mounted auxiliary drives were a known and functional solution for performing maintenance rotation in analogous heavy machinery. Applying this known technique to the PM-565 was presented as a predictable design choice, not an inventive leap.

4. Arguments Regarding Discretionary Denial

  • Petitioner argued that the Board should not exercise discretionary denial. The petition asserted that a co-pending IPR (IPR2017-02186) against the same patent did not rely on the same prior art combinations. Specifically, the Operation Manual and Parts Manual, which form the primary basis for the grounds in this petition, were not presented in the other IPR and were not considered by the USPTO examiner during the original prosecution.

5. 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.