Injector arrangement

A fuel injector for use in an internal combustion engine, the fuel injector comprising:

• an injector body comprising a bore;
• an injector needle located within the bore and engageable with a needle seat to control fuel injection through an injector outlet, the injector needle comprising an armature seat;
• an armature member which is hollow, thereby defining an internal surface of the armature member, the armature member being engageable with the armature seat on the injector needle, the injector needle in part and the internal surface of the armature member in part defining a control chamber;
• an actuator arrangement arranged to control fuel pressure within the control chamber such that fuel pressure variations within the control chamber controls movement of the injector needle relative to the needle seat;
• wherein the actuator arrangement is arranged to be capable of moving the armature member from a seated position in which it engages the armature seat to an unseated position in which the armature member has moved relative to the armature seat in order to bring the control chamber into fluid communication with a low pressure drain which circumferentially surrounds the control chamber.