Injector method of switching between injection state and drain state

An injector, comprising:

• an injector body comprising an inlet passage configured to receive fluid from an inlet port at the injector body, a drain outlet, at least one injection outlet configured to deliver fluid, and a central bore, and the inlet port is positioned longitudinally intermediate the drain outlet and the at least one injection outlet;
• a needle valve disposed for reciprocal movement within the central bore between a closed position and an opened position, the needle valve comprising a plunger head, a valve tip and an elongated body between the plunger head and the valve tip;
• and
• an actuator configured to move the needle valve between the closed position wherein an angled upper surface of the valve tip engages an angled lower surface of the injector body to form a first seal that inhibits flow through the at least one injection outlet, and the opened position wherein an angled lower surface of the plunger head engages an angled upper surface of the injector body to form a second seal that inhibits flow through the drain outlet.

An injector, comprising:

• an injector body comprising an inlet passage configured to receive fluid from an inlet port at the injector body, a drain outlet, at least one injection outlet configured to deliver fluid, and a central bore, and the inlet port is positioned longitudinally intermediate the drain outlet and the at least one injection outlet;
• a needle valve disposed for reciprocal movement within the central bore between a closed position and an opened position, the needle valve comprising a piston, a valve tip and an elongated body between the piston and the valve tip;
• and
• an actuator mounted to the injector body, the actuator being configured to move the needle valve between the closed position wherein an angled lower surface of the valve tip engages an angled upper surface of the injector body to form a first seal that inhibits flow through the at least one injection outlet, and the opened position wherein an angled upper surface of the piston engages an angled lower surface of the injector body to form a second seal that inhibits flow through the drain outlet.