Device for coupling a syringe to an actuator

A system for reversibly coupling a syringe for injecting a calibrated product to an actuator comprising the actuator, the syringe provided with a pusher having a pusher button and a coupling device, the coupling device comprising an internal body with longitudinal axis and an outer sleeve intended to move with respect to the internal body along the longitudinal axis, the internal body comprising a sliding pin ending with a play-take-up plate that is held longitudinally inside the internal body in a rest position by a prestressed spring as well as at least one pair of hooks arranged longitudinally inside the internal body mounted pivoting and retractable two by two with respect to two respective pins perpendicular to the longitudinal axis, an external part of the hooks being located opposite an internal part of the sleeve, the hooks of a same pair each having a zone for hooking to a proximal end of the play-take-up plate, and being connected to each other to a distal end by a return spring,

• wherein the distal part of the hooks is provided, outwards, with a bulge intended to be inserted into a hollow zone of a first depth of the internal profile of the sleeve in a rest position of the coupling device where the hooks is are upright and in position for horizontally locking the pusher button with the play-take-up plate,
• wherein—the relative sliding of the sleeve with respect to the internal body, wherein the sleeve moves away from the distal end of the hooks causes the hooks to open by pivoting about their respective pivoting pins, because the bulge of each hook penetrates in the direction opposite that of the motion of the sleeve, a hollow zone of a second depth of the internal profile of the sleeve the hollow zone of a second depth being adjacent to the hollow zone of a first depth, the first depth being greater than the second depth, and
• wherein the region for hooking the hook is defined by a protruding portion with an inwardly sloping chamfer followed by a recess below the protruding portion, the recess being dimensioned so as to lock by means of the hooks, the play-take-up plate adjoining the pusher button of the syringe, the play-take-up plate exerting, thanks to the prestressed spring, a force directed toward the pusher button so as to eliminate any play between the pusher button and the coupling device.