PTAB

IPR2019-00310

Nelson Products Inc v. Bal Seal Engineering Inc

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Method For Controlling Connect And Disconnect Forces Of A Connector
  • Brief Description: The ’623 patent discloses a latching connector and method where a pin slidably engages a housing. The connection is maintained by a radial canted coil spring situated in grooves within both the pin and housing, allowing for different and controllable connection and disconnection forces.

3. Grounds for Unpatentability

Ground 1: Obviousness over Guertin, the ’462 Patent, and the ’276 Patent - Claims 1-12, 25, 27, 29-31 and 33 are obvious over Guertin in view of the ’462 and ’276 patents.

  • Prior Art Relied Upon: Guertin (Patent 5,433,247), the ’462 Patent (Patent 4,655,462), and the ’276 Patent (Patent 5,139,276).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Guertin disclosed the core elements of the claimed connector method, including a pin and housing with corresponding grooves, a canted coil spring, and a connection force that is substantially lower than the disconnection force. Guertin explicitly stated its spring was of the type disclosed in the ’462 patent, which Petitioner asserted taught a radial canted coil spring. For the limitation of a "solid body" pin, which Guertin's pin was not, Petitioner pointed to the ’462 patent’s disclosure of a solid body rod used with a radial canted coil spring in a push-pull mechanism. To meet limitations related to controlling forces via the spring's orientation (e.g., a "concave orientation" or "turn angle"), Petitioner cited the ’276 patent, which taught that varying the turn angle of a radial canted coil spring predictably alters the resulting connection forces.
    • Motivation to Combine: A POSITA would combine these references to achieve a predictable result. It would have been a simple design choice to substitute the hollow pin in Guertin's fuel coupling with the solid body pin taught by the ’462 patent for applications not requiring fluid passage. Similarly, a POSITA seeking to fine-tune the connect/disconnect forces of the Guertin connector would have been motivated to apply the known principles of spring turn angles taught by the ’276 patent to achieve greater or different forces.
    • Expectation of Success: Petitioner contended that a POSITA would have had a reasonable expectation of success, as the combination involved substituting known components (a solid pin for a hollow one) and applying a known force-adjustment technique (varying a spring's turn angle) to a standard connector design, with each element performing its expected function.

Ground 2: Obviousness over Guertin, the ’462 Patent, the ’276 Patent, DM3M, and the ’078 Patent - Claims 13-24, 26, 28, and 32 are obvious over the combination of Ground 1 in view of DM3M and the ’078 Patent.

  • Prior Art Relied Upon: Guertin (Patent 5,433,247), the ’462 Patent (Patent 4,655,462), the ’276 Patent (Patent 5,139,276), DM3M (Bal Seal Catalog DM3M), and the ’078 Patent (Patent 5,108,078).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground built upon the combination in Ground 1 to address additional limitations in a separate set of claims. For the limitation requiring the spring to contact "two tapered surfaces of the pin groove," Petitioner cited the DM3M catalog, which showed this exact configuration in a housing-mounted latching connector. For the limitation of "a retainer attached to the housing to form a sidewall of the housing groove," Petitioner pointed to the ’078 patent, which explicitly showed a retainer screwed to a housing to form a groove sidewall.
    • Motivation to Combine: A POSITA would combine these additional references for known advantages. DM3M’s configuration would be incorporated to provide a standard housing-mounted assembly. The retainer from the ’078 patent would be included because retainers were well-known for facilitating the assembly and securing of springs within housing grooves.
    • Expectation of Success: Combining these features was argued to be predictable, as it involved incorporating known structural elements (a retainer, a specific groove/spring interface) for their conventional purposes into the base connector taught by Guertin.

Ground 3: Obviousness over Richards, the ’276 Patent, and DM3M - Claims 1-12, 25, 27, 29-31 and 33 are obvious over Richards in view of the ’276 patent and DM3M.

  • Prior Art Relied Upon: Richards (Patent 5,570,719), the ’276 Patent (Patent 5,139,276), and DM3M (Bal Seal Catalog DM3M).

  • Core Argument for this Ground:

    • Prior Art Mapping: This ground presented an alternative to Ground 1, using Richards as the primary reference. Petitioner argued Richards taught a breakaway fuel coupling with all the basic elements of claim 1: a pin, housing, registering grooves, and a circular canted-coil spring to provide preselected engagement and disengagement forces. As with Guertin, Richards’s pin was hollow. Petitioner cited DM3M and the ’462 patent as teaching the use of a solid body pin with a radial canted coil spring in a latching connector. The ’276 patent was again relied upon to teach the use of a "turn angle" to control forces by modifying the spring's orientation.
    • Motivation to Combine: The motivation was parallel to Ground 1. A POSITA would have found it obvious to try replacing Richards's hollow pin with a solid pin from DM3M for non-fluid applications, as this was one of a finite number of known design choices. A POSITA would also be motivated to apply the force-modification techniques from the ’276 patent to the spring in Richards to achieve a connector with different, predictable connect and disconnect forces.
    • Expectation of Success: The combination of familiar elements was expected to yield predictable results, as each component would perform its known function within the established framework of the Richards connector.

  • Additional Grounds: Petitioner asserted an additional obviousness challenge (Ground 4) against claims 13-24, 26, 28, and 32 based on the combination of Richards, the ’276 Patent, DM3M, and the ’078 Patent. This ground paralleled the logic of Ground 2, adding the teachings of the ’078 patent (retainer) and DM3M (groove geometry) to the primary Richards reference.

4. Key Technical Contentions (Beyond Claim Construction)

  • Nature of Prior Art Springs: A central contention of the petition was that the examiner erred during a prior ex parte reexamination by concluding that the springs in Guertin and Richards were only suitable for axial, not radial, loading. Petitioner presented new evidence, including expert declarations and industry documents, to argue that the canted coil springs disclosed in both Guertin and Richards were in fact radial springs, designed for radial loading, and that a POSITA would have understood them as such. This re-characterization was foundational to all asserted grounds of unpatentability.

5. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 1-33 of Patent 8,166,623 as unpatentable.