Invalidity dossier
US 8539783
System for preventing condensation on refrigerator doors and frames
Current assignee: SUPERMARKET ENERGY TECHNOLOGIES LLC
Added 9/23/2026, 10:12:41 PM
Active provider: DeepSeek · deepseek-v4-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US8539783B1
Title: System for preventing condensation on refrigerator doors and frames.
Patent number: US8539783B1. Application: US12/710,285, filed 2010-02-22. Granted/publication date: 2013-09-24. Priority date listed: 2004-02-11, claiming priority from US10/778,289 (US7240501B2) and US11/228,602 (US20060026975A1). Inventor: John Bunch. Original/current assignee: Supermarket Energy Tech LLC (assignment recorded as Supermarket Energy Technologies, L.L.C.). Status listed: Expired – Fee Related, adjusted expiration 2026-04-30. Classifications include A47F3/04 and F25D21/04.
Purpose. Shopkeepers display refrigerated or frozen products in temperature-controlled cases with glass doors or open "coffin" coolers (referred to collectively as "refrigerators"). Temperature and humidity changes cause condensation and frost on doors and frames; door condensation obstructs product visibility, and frame condensation can drip and pool, creating unsafe floors. The invention therefore manages refrigerator energy consumption while maintaining protection against condensation.
Plain-language scope. A control unit connects to door heater(s) via a door heater wire and frame heater(s) via a frame heater wire, and is configured to operate the frame heaters independently of the door heaters—avoiding the known inefficiency of activating both heaters when only one is needed. The control unit communicates with condensation sensors to decide when to power the heaters, and may activate a heater before condensation is detected but is anticipated. It also communicates with fan sensors to monitor fan power consumption and alert on erratic fan power, monitors water level to protect fans (typically mounted low), and controls power to refrigerator lights. It may communicate with humidity, temperature, light, and motion sensors. The control unit and sensors are capable of wireless data transmission, and a command unit enables remote monitoring and control, potentially over the Internet. A stated object is a quick-disconnect plug connection to power for easier installation, repair, and replacement.
Not established by this excerpt. The excerpt does not establish the full claim set, the complete written description, the figures' details (FIG. 3 is truncated), any litigation, ownership transfers, validity, or prior-art analysis.
Source: https://patents.google.com/patent/[US8539783](/patent/US8539783)/en
Generated 10/1/2026, 9:33:42 PM
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Litigation summary
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Proceedings on file (0)
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PTAB challenges
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Assignment history
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Prior art
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Obviousness
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Extensions
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Derivative works
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