Patent ID: 7028664

Claim:
A motor brake for an internal combustion engine having an exhaust valve ( 2 ) and an operating mechanism ( 1 ) for opening and closing the exhaust valve ( 2 ), said operating mechanism ( 1 ) including a support cylinder ( 5 ) firmly connected to, or being part of, the internal combustion engine, a pressure piston ( 11 ) movably supported in the support cylinder ( 5 ) and a valve opening piston ( 10 ) also movably supported in the support cylinder ( 5 ) between the pressure piston ( 11 ) and the exhaust valve ( 2 ) for transmitting the valve opening force from the pressure piston ( 11 ) to the exhaust valve ( 2 ), said hydraulic piston ( 10 ) including a bore ( 16 ) and the pressure piston ( 11 ) including a lug ( 14 ) received in the bore of the hydraulic piston ( 10 ), said valve opening piston ( 10 ) and said pressure piston ( 11 ) being supported in the hydraulic cylinder ( 9 ) so as to be axially movable relative to each other.