Valve bridge with integrated spline bushing for lost motion and engine brake

A method of operating a rocker arm assembly during an engine braking function, an engine braking lost motion function, a normal operation mode, and a cylinder deactivation function, the rocker arm assembly comprising:

• a main body rotatable about a shaft, the main body having a roller end and a valve end;
• a first switchable castellation assembly disposed in the valve end, the first switchable castellation assembly having a distal end configured to selectively move a first valve, the first switchable castellation assembly movable between a deactivated position wherein rotation of the main body about the shaft is not transferred to the first valve via the first switchable castellation assembly and an activated position wherein rotation of the main body about the shaft is transferred to the first valve via the first switchable castellation assembly;
• and a second switchable castellation assembly disposed in the valve end, the second switchable castellation assembly having a distal end configured to engage a valve bridge assembly, the valve bridge assembly configured for engaging and actuating a second valve, the second switchable castellation assembly movable between an activated position wherein rotation of the main body about the shaft is transferred to the second valve via the valve bridge assembly and the second switchable castellation assembly and a deactivated position wherein rotation of the main body about the shaft is not transferred to the second valve via the valve bridge assembly and the second switchable castellation assembly, the method comprising;
• for the engine braking function:
• 1) Moving the first switchable castellation assembly to the activated position;
• and
• 2) Rotating the main body a predetermined distance sufficient to actuate the first valve via the first switchable castellation assembly for the engine braking function wherein the second switchable castellation assembly internally collapses to prevent a transfer of motion to the valve bridge assembly via the second switchable castellation assembly,
• for the engine braking lost motion function
• 1) Moving the first switchable castellation assembly to the deactivated position;
• and
• 2) Rotating the main body the predetermined distance sufficient to actuate the first valve via the first switchable castellation assembly for the engine braking function wherein the first switchable castellation assembly experiences lost motion and motion is not transferred to the first valve via the first switchable castellation assembly and wherein the second switchable castellation assembly internally collapses to prevent a transfer of motion to the valve bridge assembly via the second switchable castellation assembly,
• for the normal operation mode:
• 1) Moving the first switchable castellation assembly to the deactivated position and the second switchable castellation assembly to the activated position, and
• 2) Rotating the main body a predetermined distance sufficient to actuate the second valve via the second switchable castellation assembly for the normal operation mode wherein the first switchable castellation assembly experiences lost motion and motion is not transferred to the first valve via the first switchable castellation assembly, and
• for the cylinder deactivation function:
• 1) Moving the first switchable castellation assembly to the deactivated position and the second switchable castellation assembly to the deactivated position;
• and
• 2) Rotating the main body the predetermined distance sufficient to actuate the second valve via the second switchable castellation assembly for the normal operation mode wherein the first valve experiences lost motion via the first switchable castellation assembly and the second valve experiences lost motion via the second switchable castellation assembly.