Top IPC subclasses
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1
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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
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|
2
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G05F
|
2
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systems for regulating electric or magnetic variables
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|
3
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F02B
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2
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Internal-combustion piston engines; combustion engines in general
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|
4
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H01C
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1
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resistors
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|
5
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C01B
|
1
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non-metallic elementscompounds thereof
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|
6
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G01R
|
1
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Measuring electric variables; measuring magnetic variables
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|
7
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C01G
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1
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Compounds containing metals not covered by subclasses C01D or C01F
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|
8
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H02J
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1
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circuit arrangements or systems for supplying or distributing electric powersystems for storing elec
|
|
9
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C01F
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1
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compounds of the metals beryllium, magnesium, aluminium, calcium, strontium, barium, radium, thorium
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|
10
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G01K
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1
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measuring temperaturemeasuring quantity of heatthermally-sensitive elements not otherwise provided f
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