Top IPC subclasses
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1
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F24J
|
20
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Production or use of heat not otherwise provided for
|
|
2
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H02J
|
6
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circuit arrangements or systems for supplying or distributing electric powersystems for storing elec
|
|
3
|
F03D
|
4
|
Wind motors
|
|
4
|
H02M
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4
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apparatus for conversion between ac and ac, between ac and dc, or between dc and dc, and for use wit
|
|
5
|
H01M
|
3
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processes or means, e.g. batteries, for the direct conversion of chemical energy into electrical ene
|
|
6
|
G08B
|
2
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signalling or calling systemsorder telegraphsalarm systems
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|
7
|
H05B
|
2
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electric heatingelectric lighting not otherwise provided for
|
|
8
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H01L
|
2
|
Semiconductor devices; electric solid state devices not otherwise provided for
|
|
9
|
F24S
|
2
|
|
|
10
|
H03K
|
1
|
pulse technique
|
|
11
|
B63H
|
1
|
marine propulsion or steering
|
|
12
|
B60L
|
1
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electric equipment or propulsion of electrically-propelled vehiclesmagnetic suspension or levitation
|
|
13
|
F24D
|
1
|
domestic- or space-heating systems, e.g. central heating systemsdomestic hot-water supply systemsele
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