an autoinjector an autoinjector device having a housing (212), (214), a cartridge for containing a medicament, a first needle tip (230) arranged to penetrate said cartridge, a second needle tip (230) for injecting said medicament on a target, said first and second needle tips being in fluid communication, a plunger rod (242) for moving said cartridge to be punctured by said first needle, said plunger rod (242) ) having a recess (270) at a respective end, the improvement comprising a battery (258), a printed circuit board (250) communicating electrically with said battery, an electrically conductive element (274) having a first end in electrical communication with said battery (258), and a printed circuit board (250), a second end within said recess (270) on said piston rod (242), said second end being electrically A richly isolated, coil spring (246) surrounding said electrically conductive member and being spaced therefrom, the arrangement being such that when said piston rod (242) is activated, said second end of said electrically conductive member is released from the electrically conductive member. said recess (270) in said piston rod (242) and contacts said locking ring (244) to complete an electrical circuit.auto injetor um dispositivo auto injetor, tendo um invólucro (212), (214), um cartucho para conter um medicamento, uma primeira ponta de agulha (230) disposta para penetrar no referido cartucho, uma segunda ponta de agulha (230) para injetar o referido medicamento em um alvo, as referidas primeira e segunda pontas de agulha estando em comunicação fluida, uma haste do êmbolo (242) para mover o referido cartucho, de modo a ser perfurado pela referida primeira agulha, a referida haste do êmbolo (242) tendo um recesso (270) em uma extremidade respectiva, a melhoria compreendendo uma bateria (258), uma placa de circuito impresso (250) comunicando-se eletricamente com a referida bateria, um elemento eletricamente condutor (274), tendo uma primeira extremidade em
