Self-contained compression brake control module for compression-release brake system of an internal combustion engine

A compression brake control module, in a compression-release brake system for operating at least one exhaust valve of an internal combustion engine during a compression-release engine braking operation, the compression brake control module operatively coupled to at least one exhaust valve for controlling a lift and a phase angle of said at least one exhaust valve, so as to maintain the at least one exhaust valve open during a compression stroke of the engine when the engine performs a compression-release engine braking operation, the compression brake control module comprising:

• a casing including a single-piece body, adapted for mounting within and fixedly engaging a bore within said engine, said casing including an internal actuator cavity;
• an actuation piston disposed outside the casing and within said bore so as to define a variable volume hydraulic actuation piston cavity between the casing and the actuation piston and an inner surface of said bore, the actuation piston reciprocating relative to the casing within said bore between an extended position and a collapsed position, the actuation piston being provided to engage the at least one exhaust valve in the extended position of said piston;
• the actuation piston cavity and the actuator cavity being in fluid communication with each other through a connecting passage within the body of the casing;
• a supply conduit formed within the body of the casing and connected to the connecting passage, the supply conduit adapted to provide pressurized hydraulic fluid to the actuation piston cavity through the connecting passage;
• a check valve provided between the connecting passage and the actuation piston cavity to hydraulically lock the actuation piston cavity when a pressure of the hydraulic fluid within the actuation piston cavity exceeds the pressure of the hydraulic fluid in the supply conduit, the check valve biased closed by a biasing spring;
• and
• a compression brake actuator disposed in the actuator cavity for controlling the check valve;
• the compression brake actuator including an actuator element exposed to atmospheric pressure and slidingly mounted within the actuator cavity for reciprocating between an extended position and a retracted position, and a compression spring biasing the actuator element toward a retracted position thereof in which the actuator element engages and opens the check valve solely by the biasing force of the compression spring so as to unlock the actuation piston cavity and fluidly connect the actuation piston cavity to the supply conduit;
• and
• said actuation piston includes an outer seal and smooth outer surface to engage, seal against, and reciprocate within said bore.

A compression brake control module, in a compression-release brake system, for use in an internal combustion engine for controlling a lift and a phase angle of at least one exhaust valve of said internal combustion engine, the compression brake control module comprising:

• a casing including a single-piece body, adapted for mounting within and fixedly engaging a bore within said internal combustion engine, said casing including an internal actuator cavity;
• an actuation piston disposed outside the casing and within said bore so as to define a variable volume hydraulic actuation piston cavity between the casing and the actuation piston and an inner surface of said bore, the actuation piston reciprocating relative to the casing within said bore between an extended position and a collapsed position, the actuation piston being provided to engage the at least one exhaust valve in the extended position of said piston;
• the actuation piston cavity and the actuator cavity being in fluid communication with each other through a connecting passage within the body of the casing;
• a supply conduit formed within the body of the casing and connected to the connecting passage, the supply conduit adapted to provide pressurized hydraulic fluid to the actuation piston cavity through the connecting passage;
• a check valve provided between the connecting passage and the actuation piston cavity to hydraulically lock the actuation piston cavity when a pressure of the hydraulic fluid within the actuation piston cavity exceeds the pressure of the hydraulic fluid in the supply conduit, the check valve biased closed by a biasing spring;
• and
• an actuator disposed in the actuator cavity for controlling the check valve;
• the actuator including an actuator element exposed to atmospheric pressure and slidingly mounted within the actuator cavity for reciprocating between an extended position and a retracted position, and a compression spring biasing the actuator element toward a retracted position thereof in which the actuator element engages and opens the check valve solely by the biasing force of the compression spring so as to unlock the actuation piston cavity and fluidly connect the actuation piston cavity to the supply conduit;
• and,
• said single-piece body of said compression brake control module has a partially threaded outer cylindrical surface to be engaged with said bore.