Patent ID: 7804230

Claim:
A piezoelectric actuator for use in a fuel injector, the actuator comprising: a stack of one or more piezoelectric elements for receipt within an accumulator chamber of the injector, a distribution electrode arrangement for generating an electric field within the stack, and an electrical connector arrangement including a body member formed of ceramic material and defining an external boundary, a base portion that has an upper face defining a pocket, and a separate stem portion received within the pocket and projecting from the base portion, wherein the base portion defines a base end face for abutment with the adjacent end face associated with the stack, said base end face having an outline shaped to match the outline of the adjacent end of the stack, and further defines a shoulder region formed of ceramic material forming a sealing surface having a frustoconical portion and a radiused portion for abutment with an internal frustoconical surface defined by the accumulator chamber to form a fluid tight seal without an elastomeric sealing element, the electrical connector arrangement further comprising a terminal arrangement for connecting to an external power supply so as enable voltage supply to the distribution electrode arrangement, the terminal arrangement including first and second terminal blades arranged side by side and configured to couple with a connector connected to the external power supply, first and second terminal pins attached to the first and second terminal blades respectively at one of respective first terminal pin ends, said terminal pins arranged side by side and disposed internal to the external boundary of the body member, and first and second contact plates attached to the first and second terminal pins at a respective one of second terminal pin ends opposite the first terminal pin ends, wherein each of the first and second contact plates is connected to a respective one of the first or second terminal blades by way of a respective one of the first and second terminal pins so as to form a first and second conductor path from the external power supply to the distribution electrode arrangement, and the base end face is recessed to accommodate the first and second contact plates.