Schaeffler Group USA Inc v. BorgWarner Ithaca LLC

1. Case Identification

• Case #: IPR2020-01482
• Patent #: 7,194,992
• Filed: August 24, 2020
• Petitioner(s): Schaeffler Group USA Inc.
• Patent Owner(s): BorgWarner Ithaca LLC
• Challenged Claims: 1-4

2. Patent Overview

• Title: Variable Camshaft Timing Phaser with Vane Cushioning
• Brief Description: The ’992 patent relates to variable camshaft timing (VCT) phasers for internal combustion engines. The technology purports to solve the problem of vane impact by creating a "restriction passage" between the phaser's rotor and housing, which restricts fluid outflow from a chamber to cushion the vane as it approaches its end of travel.

3. Grounds for Unpatentability

Ground 1: Claims 1 and 4 are obvious over Nakayoshi in view of Konakawa.

• Prior Art Relied Upon: Nakayoshi (Patent 6,173,686) and Konakawa (Japanese Application # JP2000-45725A).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Nakayoshi discloses all structural elements of the VCT phaser recited in independent claim 1. This includes a housing, a rotor with vanes, and fluid passages (22, 23) that become closed off by a stopper (31a, 31b) as the vane approaches the chamber wall. Petitioner contended Nakayoshi’s connecting passages (31c, 31d) form between the rotor and housing, creating a restricted fluid path exactly as claimed. Konakawa was cited to explicitly teach the purpose of such a structure: using restricted fluid outflow to "absorb the shock of a collision" between a vane and a wall.
  • Motivation to Combine: A person of ordinary skill in the art (POSITA) would combine these references because both address the same technology (VCT phasers) and a known problem (vane impact). A POSITA would have been motivated to apply the explicit cushioning solution taught by Konakawa to the structurally similar phaser of Nakayoshi to improve its durability and reduce noise, which are known design goals.
  • Expectation of Success: Success would be predictable, as the combination involves applying well-understood principles of fluid dynamics to a conventional mechanical system. Petitioner argued that modifying the size of Nakayoshi's passage to be more restrictive, as suggested by Konakawa, was a simple matter of design choice to achieve a desired level of cushioning.

Ground 2: Claims 1 and 4 are obvious over Shirai in view of Konakawa.

• Prior Art Relied Upon: Shirai (Patent 4,858,572) and Konakawa (Japanese Application # JP2000-45725A).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner asserted that Shirai, an alternative base reference, also discloses a VCT phaser with all the elements of claim 1. Specifically, Shirai teaches circumferential grooves (e.g., 50, 152, 154) formed in the external rotor that provide a restricted fluid path from a chamber to a fluid passage once the main port is closed. This structure, Petitioner argued, meets the "restriction passage" limitation. As in Ground 1, Konakawa was used to supply the express teaching of using such a restricted path for cushioning.
  • Motivation to Combine: A POSITA would combine Shirai and Konakawa to enhance the performance of Shirai's phaser. Seeing the inherent flow-restricting grooves in Shirai, a POSITA would have recognized their potential for cushioning and been motivated by Konakawa's explicit teachings to implement or optimize those grooves to predictably reduce vane impact and noise.
  • Expectation of Success: A POSITA would have had a high expectation of success because Shirai already provides the necessary structure (grooves), and Konakawa confirms the functional benefit of using such a structure for cushioning. Modifying the shape or dimensions of Shirai's grooves based on Konakawa's teachings was presented as a routine design optimization.

Ground 4: Claims 2 and 3 are obvious over Nakayoshi and Konakawa in view of Butterfield.

• Prior Art Relied Upon: Nakayoshi (Patent 6,173,686), Konakawa (Japanese Application # JP2000-45725A), and Butterfield (Patent 5,657,725).

• Core Argument for this Ground:

  • Prior Art Mapping: This ground builds upon Ground 1 to challenge dependent claims 2 (cam torque actuated) and 3 (torsion assist). Petitioner argued that while Nakayoshi and Konakawa disclose oil-pressure actuated phasers, Butterfield explicitly teaches cam torque actuation and torsion assist actuation as well-known, interchangeable alternatives in the VCT phaser field. Butterfield describes systems using "torque reversals" (cam torque) and hybrid systems with check valves (torsion assist).
  • Motivation to Combine: A POSITA would have been motivated to modify the phaser of Nakayoshi/Konakawa with the actuation methods from Butterfield as a matter of design choice. Butterfield presents these actuation methods as conventional options, the selection of which depends on factors like engine type and performance requirements. The motivation was simply to use a known actuation system in a known device.
  • Expectation of Success: Success was predictable because it involved substituting one known, conventional actuation module for another within a standard VCT phaser, a common practice in the field.

• Additional Grounds: Petitioner asserted additional obviousness challenges against claims 2 and 3 based on Shirai/Konakawa in view of Butterfield (Ground 5) and against all claims based on Komazawa (Japanese Application # JP2001-317314A), alone or in view of Butterfield (Grounds 3 and 6). These grounds relied on similar arguments regarding the presence of inherent restriction passages and the interchangeability of known actuation methods.

4. Key Claim Construction Positions

• "restriction passage": Petitioner argued for its plain and ordinary meaning: "a channel through or by which fluid passes such that flow is limited." This construction was central to the petition's arguments, as Petitioner contended it is broad enough to encompass conventional clearances (e.g., a "running fit") between a rotor and housing, which are present in the prior art for lubrication and rotation. This position aimed to counter arguments made by the Patent Owner during prosecution that the prior art lacked such a passage.
• "cushioning": Petitioner proposed this term means "increasing backpressure against the vane due to fluid flow through the restriction passage." Petitioner argued this is merely a functional description of the natural and inherent physical result of any fluid flow restriction. Therefore, if a prior art reference discloses a structure that restricts flow, it inherently provides "cushioning," regardless of whether the reference explicitly uses that term.

5. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under §325(d) would be inappropriate because the petition's primary references (Nakayoshi, Konakawa, Komazawa) were not considered during prosecution. Petitioner asserted these references teach the very feature—a restriction passage formed along the rotor circumference—that the Examiner previously found to be missing from the art of record, meaning the challenges are not cumulative.
• Petitioner also argued against discretionary denial under Fintiv factors. The petition was filed shortly after the answer in the co-pending district court litigation, with no discovery having occurred and no trial date set. Petitioner contended that the IPR proceedings would conclude well before any potential trial and would therefore simplify issues and promote judicial economy.

6. Relief Requested

• Petitioner requests the institution of an inter partes review and the cancellation of claims 1-4 of Patent 7,194,992 as unpatentable.