DCT
1:21-cv-00942
Glaston Corp v. HHH Equipment Resources
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Glaston Corporation (Finland) and Uniglass Engineering Oy (Finland)
- Defendant: Salem Fabrication Technologies Group, Inc. d/b/a HHH Equipment Resources (North Carolina)
- Plaintiff’s Counsel: Parker Poe Adams & Bernstein LLP; Sughrue Mion, PLLC
- Case Identification: 1:21-cv-00942, M.D.N.C., 01/27/2022
- Venue Allegations: Venue is asserted to be proper in the Middle District of North Carolina because the Defendant is incorporated in and resides in the district.
- Core Dispute: Plaintiffs allege that Defendant’s importation, sale, and use of certain convection glass tempering furnaces infringes two patents related to methods and apparatuses for heating glass.
- Technical Context: The technology concerns industrial furnaces used for tempering glass, a process that improves its strength and safety by controlled heating and cooling.
- Key Procedural History: The complaint alleges that Plaintiffs notified Defendant of the patents-in-suit and their belief of infringement in November 2020, over a year before the amended complaint was filed, which may form the basis for the willfulness allegations.
Case Timeline
| Date | Event |
|---|---|
| 2003-06-24 | Priority Date for ’540 and ’911 Patents |
| 2013-07-09 | U.S. Patent No. 8,479,540 Issued |
| 2014-02-18 | U.S. Patent No. 8,650,911 Issued |
| 2020-11-01 | Alleged Pre-Suit Notification of Infringement to Defendant |
| 2022-01-27 | Amended Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 8,650,911 - Method and Apparatus for Heating Glass (Issued Feb. 18, 2014)
The Invention Explained
- Problem Addressed: Conventional glass tempering furnaces can heat glass unevenly, particularly "selective glass" which is coated to reflect thermal radiation. This uneven heating can cause optical errors and requires longer processing times, reducing furnace capacity (Compl. ¶18; ’911 Patent, col. 1:33-43).
- The Patented Solution: The invention describes a dual-system heating apparatus. The top surface of the glass is heated by convection using hot air that is sucked from inside the furnace, pressurized, and recirculated. The bottom surface is heated by aspiration, where fresh air is taken from outside the furnace, pressurized by a separate compressor, heated, and blown onto the lower glass surface. This combination provides more controlled and efficient heating (’911 Patent, Abstract; col. 2:17-26).
- Technical Importance: This dual-heating approach is intended to enable faster and more uniform heating for difficult-to-process coated glass, thereby increasing manufacturing throughput and quality (’911 Patent, col. 2:40-51).
Key Claims at a Glance
- The complaint asserts independent Claim 1 (Compl. ¶21).
- Claim 1 requires an apparatus with:
- A tempering furnace with horizontal rolls forming a conveyor.
- An upper side return pipe for sucking air from inside the furnace.
- A pressurization unit for the sucked air.
- Means for blowing the pressurized, recirculated air onto the upper glass surface.
- A compressor for pressurizing air taken from outside the furnace.
- A pipe system for conveying the externally-sourced, pressurized air to a lower glass surface.
- Means for heating the air pressurized by the compressor.
- The complaint states its allegations are "exemplary," suggesting the right to assert other claims may be reserved (Compl. ¶17).
U.S. Patent No. 8,479,540 - Method and Apparatus for Heating Glass (Issued July 9, 2013)
The Invention Explained
- Problem Addressed: The patent, which shares a specification with the ’911 Patent, identifies the same problem of uneven heating in roller furnaces, especially the tendency of glass edges to curve upwards and the difficulty of heating selective glass that reflects radiation (’540 Patent, col. 1:21-40).
- The Patented Solution: The invention is a method of heating glass that implements the dual-system concept. The method consists of heating the upper glass surface with jets of recycled hot air from within the furnace, while simultaneously blowing externally-sourced, compressed, and heated air onto the lower surface of the glass (’540 Patent, Abstract; col. 6:50-65).
- Technical Importance: The method aims to solve the uneven heating problem by applying heat differently to the top and bottom surfaces, allowing for a more balanced and rapid thermal treatment process (’540 Patent, col. 2:31-36).
Key Claims at a Glance
- The complaint asserts independent Claim 1 (Compl. ¶40).
- Claim 1 is a method claim where the "improvements consist[] essentially of":
- Heating an upper surface of the glass with hot air jets formed by sucking, pressurizing, and recycling air from inside the furnace.
- Blowing air that has been taken from outside the furnace, pressurized by a compressor, and heated onto a lower surface of the glass.
- The complaint’s allegations are presented as "exemplary," preserving the option to assert additional claims (Compl. ¶39).
III. The Accused Instrumentality
Product Identification
- The accused products are the "Northglass's AU series glass tempering furnaces" (Compl. ¶22).
Functionality and Market Context
- The complaint alleges the accused furnaces utilize a dual-heating system marketed as "Upper convection heating" and "Bottom aspiration" (Compl. ¶23, ¶26; p. 8, Exh. 3). A marketing screenshot from Defendant's website shows a diagram of the accused furnace and its conveyor system (Compl. p. 8, Exh. 3). The upper heating allegedly uses "gapless forced convection with hot air...recirculated on the upper side to an intake of the furnace blowers" (Compl. ¶23). The bottom heating allegedly "employ[s] bottom aspiration, using compressed air to supply to the bottom surface of the glass" (Compl. ¶26).
- The complaint alleges Defendant is the "exclusive partner for NorthGlass equipment and services in North America" and that Northglass furnaces are exported globally, including to the U.S. (Compl. ¶28, ¶30).
IV. Analysis of Infringement Allegations
’911 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| An apparatus for heating glass, the apparatus comprising a tempering furnace comprising horizontal rolls arranged to carry the glass and to form a conveyor thereof, | The accused "Northglass's AU series glass tempering furnaces" are apparatuses that include a furnace with "horizontal rolls for carrying the glass and forming a conveyor." A product image shows these horizontal rollers (Compl. p. 8, Exh. 3). | ¶22 | col. 4:60-62 |
| an upper side return pipe for sucking air from inside the tempering furnace, | The accused furnaces allegedly have an upper heating system where hot air is "recirculated on the upper side to an intake of the furnace blowers." This intake allegedly functions as the return pipe. | ¶23, ¶24 | col. 5:50-54 |
| a pressurization unit for pressurizing the air sucked from inside the tempering furnace, | The accused furnaces are alleged to have "multiple blowers in blower housings mounted to the side of the furnace for pressurizing air." An annotated image points out these "Blower housings" (Compl. p. 10, Exh. 5). | ¶25 | col. 5:48-49 |
| means for blowing the pressurized air back to an upper surface of the glass, | The accused furnaces allegedly heat the glass from the top with "gapless forced convection with hot air delivered through top air nozzles." | ¶23 | col. 5:6-14 |
| a compressor for pressurizing air taken from outside the furnace, | The accused furnaces are alleged to "employ bottom aspiration, using compressed air." The complaint asserts this compressed air system meets the compressor limitation. Marketing materials for the furnace explicitly list "Bottom aspiration" as a feature (Compl. p. 11, Exh. 6). | ¶26 | col. 5:35-36 |
| a pipe system for conveying the air pressurized by the compressor to a lower surface of the glass, and | The accused furnaces allegedly deliver compressed air to the bottom of the glass "via air openings in conduits located beneath the glass/rollers." | ¶44 | col. 5:24-25 |
| means for heating the air pressurized by the compressor. | The complaint alleges the accused furnaces use "bottom aspiration... to supply to the bottom surface of the glass and aid in heating." | ¶26 | col. 5:25-29 |
’540 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| the improvements consisting essentially of heating an upper surface of the glass by hot air jets formed by sucking hot air from inside the furnace, pressurizing the hot air and recycling the pressurized hot air back to the upper surface of the glass for the heating from above, and | The accused furnaces are alleged to "heat the upper surface of the glass with gapless forced convection that uses pressurized hot air recycled from the surface of the glass back through an intake of the furnace blowers." A marketing screenshot highlights this "Top Convection" feature (Compl. p. 17, Exh. 14). | ¶42 | col. 4:5-13 |
| blowing air which has been taken from outside the furnace and which has been pressurized by a compressor and heated onto a lower surface of the glass for the heating from below. | The accused furnaces allegedly "employ[] bottom aspiration," which is described as involving "the use of compressed air to move the air and thereby aid in heating." The complaint alleges this functionality meets the claim limitation. Marketing materials explicitly identify "Bottom Aspiration" (Compl. p. 17, Exh. 14). | ¶43, ¶44 | col. 4:2-6 |
- Identified Points of Contention:
- Scope Questions: The case may turn on whether the accused product's "blower housings" (Compl. ¶25) for the upper heating system meet the definition of a "pressurization unit," and whether its "bottom aspiration" system (Compl. ¶26) falls within the scope of a system using a "compressor" that takes air from "outside the furnace." The defense may argue these are technically distinct systems.
- Technical Questions: A key factual question will be how the "bottom aspiration" system of the accused furnace actually operates. The complaint alleges it uses "compressed air" (Compl. ¶26), but the patent requires that this air be taken from outside the furnace, pressurized, and heated. The evidence will need to show a direct correspondence between the accused product's operation and this multi-step claimed process.
V. Key Claim Terms for Construction
The Term: "pressurization unit" (’911 Patent, Claim 1)
- Context and Importance: This term is central to the upper, recirculated heating system. Whether the accused "furnace blowers" (Compl. ¶23) infringe will depend on the construction of this term. Practitioners may focus on this term because the patent discloses a very specific, high-speed embodiment that may differ from a standard industrial blower.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent states the unit "pressurizes the air mainly by compressing, i.e. by applying the compression principle," which could be argued to encompass any device that increases air pressure, such as a blower (’911 Patent, col. 5:55-57).
- Evidence for a Narrower Interpretation: The specification describes a specific embodiment with a rotation speed of "more than 15,000 rotations per minute" and suggests it "may be e.g. a heat endurance compressor or a turbine of a turbocharger," which could support a narrower definition requiring a high-speed, high-compression device (’911 Patent, col. 5:57-62).
The Term: "compressor" (’911 Patent, Claim 1; ’540 Patent, Claim 1)
- Context and Importance: This term defines a critical component of the lower, external-air heating system. The infringement allegation hinges on mapping this term to the accused "bottom aspiration" system.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent describes the compressor as deriving its air "from the factory hall," suggesting a standard industrial air source rather than a specialized one (’911 Patent, col. 5:35-36). This could support a plain and ordinary meaning.
- Evidence for a Narrower Interpretation: An embodiment describes the compressor conveying air to a "pressure tank 22" which may hold a pressure of "e.g. 7 bar," a relatively high pressure (’911 Patent, col. 5:36-40). This could be used to argue that the term implies a high-pressure system, not just any device that moves air.
The Term: "consisting essentially of" (’540 Patent, Claim 1)
- Context and Importance: This transitional phrase is legally significant because it limits the claim to the recited steps and any unrecited steps that do not materially affect the basic and novel properties of the invention. The definition of these properties will be critical.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation (of what is permitted): Plaintiffs will likely argue the basic and novel property is the dual-mode heating to achieve faster, more uniform results on selective glass. Any additional, unrecited steps in the accused method that do not interfere with this core function would not defeat infringement.
- Evidence for a Narrower Interpretation (of what is permitted): Defendant may argue the basic and novel characteristics are more specific, such as the precise temperature differentials or airflow controls described in the specification. If the accused method includes other steps that alter these characteristics, Defendant could argue non-infringement.
VI. Other Allegations
- Indirect Infringement: The complaint alleges both induced and contributory infringement. The inducement claim is based on Defendant's alleged "active marketing," "installation, training and customer support," and consulting services that allegedly encourage customers to operate the furnaces in an infringing manner (Compl. ¶31, ¶33, ¶48). The contributory infringement claim is based on allegations that the accused furnaces are a material component of the patented method, are especially adapted for infringement, and have no substantial non-infringing uses (Compl. ¶34, ¶49).
- Willful Infringement: The willfulness claim is based on alleged pre-suit knowledge. The complaint alleges that Plaintiffs notified Defendant of the ’911 and ’540 patents and its belief of infringement in November 2020, and that Defendant's allegedly infringing conduct continued thereafter (Compl. ¶35, ¶36, ¶50, ¶51).
VII. Analyst’s Conclusion: Key Questions for the Case
- A central issue will be one of claim construction: Can the terms "pressurization unit" and "compressor", which are described in the patent specification with specific performance characteristics (e.g., >15,000 RPM, 7-bar pressure), be construed broadly enough to cover the accused furnace's "blower" and "aspiration" systems?
- A key evidentiary question will be one of technical operation: Does the accused "bottom aspiration" system function in a manner equivalent to the claimed method of taking air from outside the furnace, pressurizing it, heating it, and then blowing it onto the glass, or is there a fundamental operational difference that places it outside the claim scope?
- A third question concerns the transitional phrase in the method patent: What are the "basic and novel properties" of the claimed method? The answer will determine whether any additional, unrecited steps in the accused process are sufficient to avoid infringement under the "consisting essentially of" limitation.