USPC Class Details – HistoricIP

Description: 91 motors: expansible chamber type / 91 motors: expansible chamber type/(218) cyclically operable (277) adjustable working member reversal position (e.g., stroke control, etc.)

Hierarchy/Derived subclasses

91 / 218	-> 277	-> 278
		-> 279

uspto searches

Patent Apps in 91/277

Granted Patents in 91/277

Use the links above or do an advanced search in ppubs for:
(91/277.ccls. or 91/278.ccls. or 91/279.ccls.)

This will show what classes derive from the input. Ex: entering 43/42.24 shows the derived classes and the search that can be used to find patents or patent applications in those subclasses.