DIFF Subgroup
F01B 7/20 with two or more pistons reciprocating one within another, e.g. one piston forming cylinder of the other
Introduced: September 1968
Full Title
Full titles differ between systems:
IPC:
Machines or engines with two or more pistons reciprocating within same cylinder or within essentially coaxial cylinders > with two or more pistons reciprocating one within another, e.g. one piston forming cylinder of the other
CPC:
Machines or engines with two or more pistons reciprocating within same cylinder or within essentially coaxial cylinders (in opposite arrangement relative to main shaft F01B1/08) > with two or more pistons reciprocating one within another, e.g. one piston forming cylinder of the other
No child classifications to compare. This is a leaf node in both IPC and CPC.