The purpose of the present invention is to further reduce the size and weight of an applicator.An applicator (A1) is provided with a housing (10), a piston plate (20), a micro-needle array (30), a conical coil spring (40), and an unlocking member (50). The housing (10) has a cylindrical body section (12) for housing the piston plate (20) and the conical coil spring (40), and also has a lid section (14) for gripping the conical coil spring (40) between the lid section (14) and the piston plate (20). The body section (12) has inner walls (12b1-12b4) for engaging the piston plate (20) with the housing (10) through protrusions (20c1-20c4). The body section (12) has vertically extending grooves (G1-G4).The piston plate (20) is guided in the axial direction of the body section (12) by the grooves (G1-G4). When the piston plate (20) is unlocked by the unlocking member (50), the piston plate (20) is moved within the body section (12) along the grooves (G1-G4) by the pressing force of the conical coil spring (40) and reaches an acting position on a skin.La présente invention a pour objectif de réduire encore la dimension et le poids dun applicateur.Un applicateur (A1) est pourvu dun boîtier (10), dune plaque (20) de piston, dune collection de micro-aiguilles (30), dun ressort hélicoïdal (40) conique et dun élément de déverrouillage (50). Le boîtier (10) comporte une section cylindrique (12) de corps afin de loger la plaque (20) de piston et le ressort hélicoïdal (40) conique et comporte une section de couvercle (14) afin de tenir le ressort hélicoïdal (40) conique serré entre la section de couvercle (14) et la plaque (20) de piston. La section (12) de corps comporte des parois intérieures (12b1-12b4) afin de mettre la plaque (20) de piston en prise avec le boîtier (10) par le biais de protubérances (20c1-20c4). La section (12) de corps comporte des rainures (G1-G4) sétendant verticalement.La plaque (20) de piston est guidée dans la direction axiale de la section (12) de corp
