Invalidity dossier
US 6006528
Air conditioning system
Current assignee: Sanyo Electric Co Ltd
Added 9/23/2026, 4:50:34 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview: US6006528A — "Air Conditioning System"
Bibliographic data (from supplied text):
- Title: Air conditioning system
- Patent number: US6006528A; Application No. US08/961,303
- Inventors: Hidetoshi Arima, Nobuhiro Idei, Hisao Honda, Kazuhiro Shimura, Naohito Sakamoto, Toshio Kubo, Mamoru Kubo, Hiroyuki Takada
- Original/current assignee: Sanyo Electric Co Ltd
- Priority date: 1996-10-31 (JP29015696A, with further JP priority filings in 1996–1997)
- Filing date: 1997-10-30; Publication/grant: 1999-12-28
- Status as listed: Expired – Fee Related; anticipated expiration 2017-10-30
- Classifications include F25B25/005 and F24F3/06
Purpose: The invention addresses problems in systems that circulate a phase-changeable fluid (gas/liquid) by specific-gravity difference between a heat source side machine and user side machines. In such natural-circulation cooling, supplying sufficient refrigerant to user side machines on higher floors or with unfavorable piping is difficult, hampering room-temperature control; using an electric pump to compensate requires extra power. The stated object is to provide an air conditioning system solving these problems.
Plain-language scope: The system circulates fluid between a heat source side machine and multiple user side machines, more than half of which are below the heat source side machine, so each user side machine can at least perform cooling. Each user side machine has a heat exchanger, a flow control valve controlling fluid volume supplied to the heat exchanger, a blower supplying conditioned air to a room, a physical-value detector sensing a value related to air-conditioned load (e.g., temperature), and a signal controller connected to these. The heat source side machine has a control unit that communicates with the signal controller and outputs a control signal to the user side machine's flow control valve, and determines a set opening ratio considering a signal.
Source: https://patents.google.com/patent/[US6006528](/patent/US6006528)/en
Not established by this excerpt: The excerpt states at least one object but does not provide the full claims, detailed description, drawings, or complete control logic (the sentence about determining set opening ratio is cut off). It also does not establish heating-mode details beyond the background discussion.
Generated 10/1/2026, 9:44:06 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
Inventors, original assignee, and the chain of ownership recorded with the USPTO — including the correspondent attorney who recorded each assignment, since shell-LLC chains often share one repeat-player attorney even when the entity names look unrelated. Surfaces NPE / patent-troll patterns: shell-entity transfers, known asserters in the chain, repeat correspondent fingerprints, pre-litigation assignments, and bankruptcy fire-sales.
Prior art
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Obviousness
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Extensions
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Derivative works
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