Patent ID: 8638108

Claim:
A contact free arrangement in a medication delivery device for determining an absolute position of a first member moveably mounted relative to a second member, the first member being rotatably mounted and restricted for movement between a first end position and a second end position over an angle of rotation exceeding one revolution, the contact free arrangement comprising: at least one track of reflector means arranged on the first member, at least one emitter means arranged on the second member, the at least one emitter means being adapted to electrically couple to a number of the reflector means, and at least one receiver means arranged on the second member, the at least one receiver means being adapted to electrically couple to a number of the reflector means, generator means for generating a signal or signals and providing such signal(s) to the at least one emitter means, and processor means for processing a signal or signals from the at least one receiver means; wherein the at least one track of reflector means forms a helical path and, wherein the at least one track of reflector means, the at least one emitter means, the at least one receiver means and the generator means are arranged in such a manner that there is provided a different electrical parameter to each respective position of the first member relative to the second member, said electrical parameter being selected from the group consisting of capacitance and inductance.