Top IPC subclasses
1
|
F24J
|
9
|
Production or use of heat not otherwise provided for
|
2
|
C02F
|
5
|
Treatment of water, waste water, sewage, or sludge
|
3
|
H01L
|
3
|
Semiconductor devices; electric solid state devices not otherwise provided for
|
4
|
B04B
|
2
|
centrifuges
|
5
|
G08B
|
2
|
signalling or calling systemsorder telegraphsalarm systems
|
6
|
B01D
|
1
|
Separation
|
7
|
A99Z
|
1
|
subject matter not otherwise provided for in this section
|
8
|
H05B
|
1
|
electric heatingelectric lighting not otherwise provided for
|
9
|
F24S
|
1
|
|
10
|
H02S
|
1
|
|