Patent ID: 8435209

Claim:
A medical device for treating a user, the device comprising: a first housing portion adapted to be carried by a user; a second housing portion configured to be selectively operatively engaged with and disengaged from the first housing portion, the first housing portion and the second housing portion configured to be movable relative to each other from a first position to a second position to operatively engage each other at the second position; a reservoir supported by one of the first and second housing portions; at least one of a drive device and a needle-inserting device supported by the other of the first housing portion and the second housing portion relative to the housing portion that supports the reservoir, such that upon the first housing portion and the second housing portion being operatively engaged at the second position, the reservoir is operatively coupled to the at least one of the drive device and the needle-inserting device; a magnet supported on the first housing portion; at least one of a first magnetically attractive material and a first magnet-responsive device supported on the second housing portion in a position to magnetically interact with the magnet when the first housing portion and the second housing portion are in the first position; at least one of a second magnetically attractive material and a second magnet-responsive device supported on the second housing portion in a position to magnetically interact with the magnet, upon the first housing portion and the second housing portion being operatively engaged at the second position; and electronic circuitry configured to detect at least one of a first magnetic interaction between the magnet and the at least one of a first magnetically attractive material and a first magnet-responsive device, and a second magnetic interaction between the magnet and the at least one of a second magnetically attractive material and a second magnet-responsive device, the circuitry configured to provide a signal or a change in state in response to detection of at least one of the first magnetic interaction and the second magnetic interaction.