Top IPC subclasses
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1
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F25B
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4
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refrigeration machines, plants, or systemscombined heating and refrigeration systemsheat pump system
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|
2
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G09B
|
3
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educational or demonstration appliancesappliances for teaching, or communicating with, the blind, de
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3
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F28F
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1
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details of heat-exchange or heat-transfer apparatus, of general application
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4
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F28D
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1
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heat-exchange apparatus, not provided for in another subclass, in which the heat-exchange media do n
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