Invalidity dossier
US 5317907
Air conditioning apparatus having ambient air-conditioning unit and a plurality of personal air-conditioning units connected to outdoor unit
Current assignee: Toshiba Corp
Added 9/23/2026, 5:04:51 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: US5317907A
Title: Air conditioning apparatus having ambient air-conditioning unit and a plurality of personal air-conditioning units connected to outdoor unit
Assignee: Toshiba Corp (original assignee); assignment recorded to Kabushiki Kaisha Toshiba, A Corp. of Japan
Inventors: Keiichiro Shimizu, Eiji Kuwahara, Manabu Kitamoto, Masao Amano, Yasunori Ichikawa, Masayuki Hibi, Keizo Iwata
Key dates: Priority date 1991-04-25; filing date 1992-04-24; granted/publication date 1994-06-07; anticipated expiration 2012-04-24. Legal status listed as "Expired - Fee Related."
Application number: US07/873,187
Purpose: To provide a multi-type air-conditioning apparatus in which the drain pipe of a personal air-conditioning unit can be omitted, simplifying construction, and in which optimum capability corresponding to the number of personal air-conditioning units being driven can be attained even when that number is small, so a comfortable air-conditioned environment is always maintained. The patent also notes that personal air-conditioning units are disposed on desks to separately air-condition spaces in a room, using a free access floor (depth at most approx. 10 cm) for refrigerant and drain piping.
Plain-language scope: The apparatus has one outdoor unit connected to an ambient air-conditioning unit and several personal air-conditioning units. The outdoor unit contains a compressor and an outdoor heat exchanger; the ambient unit has an indoor heat exchanger; each personal unit has its own indoor heat exchanger. Refrigerant is routed from the compressor to the outdoor heat exchanger, then to the ambient unit's indoor heat exchanger, and returned to the compressor, cooling the whole room. The excerpt also describes a flow dividing unit, distribution unit, and control circuits, and states the personal unit capacity is approx. 0.1–0.5 hp versus 5–10 hp for the outdoor compressor, whose minimum controllable capability is about 1 hp even when inverter-driven.
The excerpt references Japanese Patent Disclosure No. 1-203856 and U.S. Pat. No. 4,926,652 as known multi-type apparatus.
Not established by this excerpt: The full claim language and exact claim scope, complete drawing contents, and the detailed operation of the described control flowcharts (FIGS. 5–7, etc.), which are only listed. The excerpt is explicitly noted as partial, with omitted text.
Source: https://patents.google.com/patent/[US5317907](/patent/US5317907)/en
Generated 10/1/2026, 9:43:52 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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