Training device for an automatic injector

A training device for an automatic injector, comprising a cylindrical outer sleeve, a punch member having a front prod-shaped end portion, a discharge mechanism and auxiliary means for making the device ready for reuse;

• wherein the discharge mechanism is connected to and disposed in the rear portion of the sleeve, and the front portion of the sleeve comprises a holder for accommodating the punch member such that the punch member is locked against forward movement;
• the discharge mechanism comprises an inner pistol sleeve which is open at its front end, a plunger which is movable in the pistol sleeve, a coil spring which acts on the plunger and tries to move the plunger out of the front end of the inner pistol sleeve outwards, a locking device which cooperates with the plunger to prevent undesired forward movement thereof, and a safety member to block unintentional unlocking of the locking device;
• the holder for the punch member comprises a sleeve-like rear portion which is open at each end and which, after activating the device, is traversed by a rear end portion of the punch member, and a nose portion which comprises a central aperture and which serves to stop the forward movement of the punch member in the holder after activating the device and to allow the front end portion of the punch member to pass;
• the punch member is accommodated in the holder such that its rear end at least substantially engages the front end of the plunger, and its front prod-shaped end portion, which has dimensions such that it can pass through the central aperture in the nose potion of the holder outwards, is present within the holder prior to use of the device;
• the rear end portion of the punch member comprises a circumferential outwardly projecting ridge or an annular member, the front of the ridge or the annular member engaging a plurality of radially arranged, inwardly projecting raised portions which are provided on the inner wall of the sleeve-like rear portion of the holder, the sleeve-like rear portion having a five- to fourteen-sided cross-section, the ridge or annular member of the punch member and the raised portions of the inner wall of the holder being mutually proportioned such that, after activating the device, the raised portions are pushed aside by the ridges or annular member so that the forward movement of the punch member in the holder is not impeded;
• and
• the rear end portion of the punch member comprises means which, in cooperation with means provided on the inner wall of the sleeve-like rear portion of the holder, prevent undesired forward movement of the punch member in the holder, in which the device at the area of the means is proportioned so that, after activation, the wall of the holder can expand resiliently outwards within the outer sleeve to allow the punch member to pass;
• wherein the discharge mechanism is connected in the cylindrical outer sleeve by means of an outer pistol sleeve within which the inner pistol sleeve can be moved and the auxiliary means making the device ready for reuse comprises a cap which fits around the outer pistol sleeve and which comprises at least two rod-shaped members which extend within the cap and correspond to apertures recessed in the rear wall of the outer pistol sleeve and which, upon using the cap, can move the inner pistol sleeve forward with respect to the outer pistol sleeve and can fix it in this position, as a result of which the discharge mechanism can be locked.