Top IPC subclasses
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1
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H02M
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21
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apparatus for conversion between ac and ac, between ac and dc, or between dc and dc, and for use wit
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2
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H01L
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19
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Semiconductor devices; electric solid state devices not otherwise provided for
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3
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F24S
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14
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|
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4
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F03D
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13
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Wind motors
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5
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H02S
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12
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|
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6
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H02J
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6
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circuit arrangements or systems for supplying or distributing electric powersystems for storing elec
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7
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H01F
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5
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magnetsinductancestransformersselection of materials for their magnetic properties
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8
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A01G
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5
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Horticulture; cultivation of vegetables, flowers, rice, fruit, vines, hops, or seaweed; forestry; watering
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9
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F24J
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4
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Production or use of heat not otherwise provided for
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10
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F24H
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3
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fluid heaters, e.g. water or air heaters, having heat-generating means, in general
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11
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H02P
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3
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control or regulation of electric motors, generators, or dynamo-electric converterscontrolling trans
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12
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F21S
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2
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non-portable lighting devices or systems thereof
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13
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H05B
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2
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electric heatingelectric lighting not otherwise provided for
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14
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B23K
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2
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soldering or unsolderingweldingcladding or plating by soldering or weldingcutting by applying heat l
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|
15
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F24D
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2
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domestic- or space-heating systems, e.g. central heating systemsdomestic hot-water supply systemsele
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|
16
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C25B
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2
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Electrolytic or electrophoretic processes for the production of compounds or non- metals; apparatus therefor
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17
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F03B
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1
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machines or engines for liquids
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|
18
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F03C
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1
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positive-displacement engines driven by liquids
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|
19
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G01R
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1
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Measuring electric variables; measuring magnetic variables
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|
20
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F26B
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1
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Drying solid materials or objects by removing liquid therefrom
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