Rocker arm providing cylinder deactivation

A rocker arm apparatus, comprising:

• first and second outer arms connected to move together, the first and second outer arms having respective first and second recesses formed therein, each recess having a closed end and an open end facing inwardly of the outer arms;
• an inner arm located between the first and second outer arms, the inner arm having third and fourth recesses formed therein each having an open end facing outwardly of the inner arm, the inner arm being rotatable relative to the first and second outer arms between first and second positions, the open ends of the first and third recesses facing and being aligned with each other, and the open ends of the second and fourth recesses facing and being aligned with each other when the inner arm is in the first position;
• first and second pistons located at least partially in the third and fourth recesses, respectively;
• springs urging the first and second pistons outwardly towards the open ends of the third and fourth recesses, respectively, such that when the inner arm is in the first position the first and second pistons extend into the first and second recesses, respectively, thereby locking the inner arm against rotation relative to the first and second outer arms;
• and
• first and second fluid flow paths formed in the first and second outer arms, respectively, to allow fluid under pressure to be applied to the first and second recesses, respectively, wherein when the first and second pistons extend into the first and second recesses, they are pushed out of the first and second recesses, by the fluid pressure and the inner arm can be rotated relative to the first and second outer arms.