Woodfold Mfg Inc v. EMI Porta OpCo LLC

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Woodfold Mfg., Inc. (Oregon)
  • Defendant: EMI Porta OPCO, LLC (Illinois)
  • Plaintiff’s Counsel: Schwabe, Williamson & Wyatt, P.C.; Shook Hardy & Bacon
• Case Identification: 1:18-cv-03984, N.D. Ill., 06/07/2018
• Venue Allegations: Venue is alleged to be proper in the Northern District of Illinois because the Defendant is an Illinois limited liability company with its principal place of business in the district, and allegedly commits acts of infringement there.
• Core Dispute: Plaintiff alleges that Defendant’s accordion-style doors for residential elevators infringe a utility patent and a design patent related to a reinforced hinge assembly.
• Technical Context: The technology concerns the mechanical design of hinge knuckles for accordion-style doors, aiming to increase strength and rigidity to meet safety standards for applications such as residential elevator gates.
• Key Procedural History: The complaint alleges that Plaintiff notified Defendant of the asserted patents and the alleged infringement on February 12, 2018, nearly four months prior to filing suit. This notification serves as the basis for the willfulness allegations.

Case Timeline

Date	Event
2015-09-30	U.S. Patent No. 9,879,471 Priority Date
2016-06-02	U.S. Patent No. D792,190 Priority Date
2017-07-18	U.S. Patent No. D792,190 Issued
2018-01-30	U.S. Patent No. 9,879,471 Issued
2018-02-12	Plaintiff Notifies Defendant of Infringement
2018-06-07	Complaint Filed

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 9,879,471 - "Reinforced Folding Door and Hinge Assembly" (Issued Jan. 30, 2018)

The Invention Explained

• Problem Addressed: The patent background suggests that prior art accordion doors, even those using hinge knuckles made of durable materials, had "potential for additional improvement" in strength (’471 Patent, col. 1:28-31). The complaint further contextualizes this by noting the need to satisfy modern safety and deflection requirements for residential elevators (Compl. ¶10).
• The Patented Solution: The invention is a hinge assembly for an accordion door featuring a uniquely shaped hinge knuckle. This knuckle includes an "outwardly flared wedge" that extends beyond the flanges of the door panels (’471 Patent, Abstract). When the door is unfolded into a flat, closed position, this wedge makes contact with the panel flanges, acting as a stop. This contact prevents the door from over-extending and provides enhanced resistance to horizontal pressure along the entire length of the hinge (’471 Patent, col. 4:49-62; Fig. 3).
• Technical Importance: This design claims to provide a stronger, more rigid barrier, allowing accordion-style doors to meet the specific strength and deflection requirements of the ASME 17.1-2016/CSA B44-16 safety standard (Compl. ¶10).

Key Claims at a Glance

• The complaint asserts independent Claim 1 (Compl. ¶12).
• The essential elements of Claim 1 include:
  • An accordion door system with a plurality of adjacent panels.
  • A hinge assembly connecting a pair of adjacent panels, where each panel has a side edge with a "longitudinal groove" and an "extension flange."
  • The hinge assembly comprises a "hinge pin" and a plurality of "hinge knuckles" in an alternating arrangement.
  • At least one hinge knuckle has a tubular central opening, an "outwardly extending tongue" for connecting to the panel's groove, and an "outwardly flared wedge."
  • The wedge extends between and beyond the panel flanges.
  • A functional limitation whereby the wedge's outer surfaces "directly contact" the extension flanges "to limit angular un-folding extension" to a desired angle.

U.S. Patent No. D792,190 - "Hinge Knuckle for Folding Door Assembly" (Issued Jul. 18, 2017)

The Invention Explained

• Problem Addressed: Not applicable to design patents, which protect aesthetics rather than function.
• The Patented Solution: The patent protects the ornamental, non-functional design of a hinge knuckle for a folding door assembly (Compl. ¶13). The specific visual appearance is defined by the patent's figures, which depict its profile, contours, and overall shape from various angles, including a top plan view (D’190 Patent, Figs. 1-7; Compl. ¶14).
• Technical Importance: Not applicable to design patents.

Key Claims at a Glance

• Design patents contain a single claim for the ornamental design as shown in the drawings. The claim is for "[t]he ornamental design for a hinge knuckle for folding door assembly, as shown and described" (D’190 Patent, Claim; Compl. ¶13).

III. The Accused Instrumentality

Product Identification

The accused instrumentalities are "residential accordion gates" and the associated "folding door and hinge assembly" manufactured and sold by Defendant EMI Porta (Compl. ¶5, ¶16-17).

Functionality and Market Context

The accused products are accordion-type folding doors intended for use in the residential elevator industry (Compl. ¶5). The complaint alleges these doors are constructed from multiple vertical panels connected by hinge assemblies that allow the door to fold and unfold (Compl. ¶18). The complaint provides a photograph showing the accused hinge knuckles packaged for sale or shipment. (Compl. ¶19, p. 7).

IV. Analysis of Infringement Allegations

'471 Patent Infringement Allegations

The complaint alleges infringement of Claim 1 by providing annotated photographs of the accused product to map its features to the claim elements. A photograph of the accused product's hinge assembly shows components labeled "Longitudinal Grooves" and "Extension Flanges" (Compl. ¶19, p. 7). Another image purports to show the operation of the accused product, with arrows indicating the "Limited Angular Unfolding" allegedly caused by contact with the "Extension Flange" (Compl. ¶23, p. 10).

Claim Element (from Independent Claim 1)	Alleged Infringing Functionality	Complaint Citation	Patent Citation
a plurality of adjacent panels arranged vertically and side-by-side...	The accused product is an accordion folding door system composed of multiple vertical panels, as shown in a photograph of the installed product.	¶18	col. 2:32-37
a hinge assembly disposed between and interconnecting a pair of adjacent panels, each of the pair of adjacent panels including a side edge having longitudinal groove and an extension flange	The accused product's panels are interconnected by a hinge assembly and feature side edges with elements identified in a photograph as "Longitudinal Grooves" and "Extension Flanges."	¶19	col. 3:15-22
wherein the hinge assembly comprises a hinge pin, a plurality of hinge knuckles disposed vertically end-to-end in an alternating arrangement on the hinge pin...	The accused hinge assembly allegedly includes "Hinge Pins" and a plurality of hinge knuckles arranged vertically end-to-end, as depicted in photographs.	¶19, ¶21	col. 3:34-36, 56-59
at least one of the hinge knuckles comprising a tubular central opening for accepting the hinge pin, an outwardly extending tongue for connecting to a corresponding longitudinal groove... and an outwardly flared wedge that extends between and beyond the extension flanges of the panels...	The accused hinge knuckles allegedly possess a tubular opening, a concealed "Tongue" for a "Tongue and Groove Connection," and a feature identified as a "Wedge."	¶20, ¶22	col. 4:11-15, 39-43
whereby the wedge cooperates with, and respective outer surfaces of the wedge directly contact, the extension flanges to limit angular un-folding extension of the pair of adjacent panels to a maximum desired angle.	In the accused product, the "wedge" allegedly contacts the "Extension Flange" to produce a "Limited Angular Unfolding," as illustrated in an annotated photograph of the product in an extended state.	¶23	col. 4:49-55

D'190 Patent Infringement Allegations

The complaint alleges that the design of the accused hinge knuckle infringes the D'190 patent under the "ordinary observer" test (Compl. ¶37). The core of this allegation is that the visual appearance of EMI Porta's hinge knuckle is so similar to the patented design that a typical purchaser would be deceived into believing they were purchasing Woodfold's product. This allegation is supported by a close-up photograph of what is identified as the accused "Hinge Knuckle" (Compl. ¶24, p. 11), which can be compared to the patent's figures provided in the complaint (Compl. ¶13-14).

Identified Points of Contention

• Scope Questions: The complaint identifies the central pivoting element of the accused hinge as "Hinge Pins (concealed under rivet)" (Compl. ¶19). This raises the question of whether a "rivet" structure falls within the ordinary and customary meaning of the term "hinge pin" as used in the patent.
• Technical Questions: The complaint alleges the presence of a "Tongue / Tongue and Groove Connection" but notes that it is "(concealed)" (Compl. ¶22). A central evidentiary question will be whether discovery reveals an internal structure in the accused product that meets this limitation. Furthermore, the "whereby" clause requires that the wedge directly contacts the flanges to limit the unfolding angle. The case may require detailed evidence, such as expert testimony or physical inspection, to prove that this specific functional interaction occurs as claimed.

V. Key Claim Terms for Construction

• The Term: "outwardly flared wedge"

  • Context and Importance: This term describes the core inventive feature of the '471 patent, which allegedly provides the novel strengthening function. The dispute will likely center on whether the accused component's shape and function meet the definition of an "outwardly flared wedge."
  • Evidence for a Broader Interpretation: The specification suggests some flexibility in shape, stating the wedge "may alternately be square, rectangular, with curved sides or other suitable shape" (’471 Patent, col. 4:60-62).
  • Evidence for a Narrower Interpretation: The term "flared" itself implies a specific geometry. The patent repeatedly uses the phrase "outwardly flared wedge" and depicts a specific "pie-shaped" profile in its preferred embodiment, which could support a narrower construction limited to such shapes (’471 Patent, col. 4:39, Fig. 3).

• The Term: "hinge pin"

  • Context and Importance: Practitioners may focus on this term because the complaint identifies the accused element as a "rivet," creating a potential distinction (Compl. ¶19). The infringement analysis may turn on whether a "rivet" is a type of "hinge pin."
  • Evidence for a Broader Interpretation: The patent describes the element functionally as being "made of steel or other stout material" and allowing the knuckles to pivot (’471 Patent, col. 1:26-27). Plaintiff may argue that any elongated fastener that performs this pivoting function meets the claim's requirements.
  • Evidence for a Narrower Interpretation: In mechanical arts, "pins" and "rivets" can be considered distinct components with different structural characteristics and methods of installation. Defendant may argue that the term "hinge pin" does not read on a permanently deformed fastener like a rivet. The specification does not provide an explicit definition to resolve this potential ambiguity.

VI. Other Allegations

• Willful Infringement: The complaint alleges that Defendant’s infringement has been and continues to be willful (Compl. ¶33, ¶41). This allegation is based on alleged pre-suit knowledge of the patents, stemming from a notice letter Plaintiff sent to Defendant on February 12, 2018 (Compl. ¶25). The complaint further alleges that Defendant continued to sell the accused products after receiving this notice, which may support a finding of willful infringement (Compl. ¶26).

VII. Analyst’s Conclusion: Key Questions for the Case

• A core issue will be one of structural identity: does the accused hinge assembly—specifically its pivoting fastener identified as a "rivet" and its concealed connection mechanism—contain the precise structures of a "hinge pin" and an "outwardly extending tongue" connecting to a "groove," as required by Claim 1 of the '471 patent?
• A key evidentiary question will be one of functional proof: does the accused product's wedge feature perform the specific function required by the '471 patent's "whereby" clause by "directly contact[ing]" the panel flanges to "limit angular un-folding," or is there a fundamental mismatch in its technical operation?
• For the D'190 design patent, the case will depend on the "ordinary observer" test: does the overall visual appearance of the accused hinge knuckle create an impression that is substantially the same as the patented design, or are there sufficient differences in the ornamental features to distinguish them in the eye of a typical purchaser?