Patent ID: RE42355

Claim:
An injector cap for an ampoule support, comprising: a sliding sleeve mounted slidably on said ampoule support, wherein said sliding sleeve is initially forced by a pre-tensioning means into a first position in which the sliding sleeve covers a cannula, and wherein said sliding sleeve can be slid against the pre-tensioning means into a second position in which said cannula emerges from a front facing end of said sliding sleeve such that medication may be administered and wherein the sliding sleeve returns to the first position after the medication is administered ; and a blocking means for non-detachably blocking the sliding sleeve against sliding again into the second position when the sliding sleeve has been returned from the second position to the first position, wherein an inner surface of the sliding sleeve is provided with at least two protrusions protruding radially inwardly from the inner surface of the sliding sleeve, and wherein the blocking means includes a locking ring disposed inside and proximate at a front end of the sliding sleeve when the sliding sleeve is initially forced by the pre-tensioning means into the first position, and the locking ring is engageably moved along with the cannula back to the first a locking position , wherein the locking ring includes at least two locking elements protruding radially outward, and, upon return of the sliding sleeve to the first position, the at least two protrusions on the sliding sleeve abut the at least two locking elements on the locking ring to help block the sliding sleeve against sliding again into the second position when the sliding sleeve has been returned from the second position to the first position.