Vaccine injector of adjustable dose to suit patient - depending on age, etc. requires only one application for max. or min. dose

摘要

The injector comprises a handle or finger grip with an extension on which can be mounted independently removable coaxial needle heads, each with needle points projecting from the end opposite the handle. The needle points of all the needle heads are pref. co-planar and the needle heads comprise a central post integral with the handle extension and series of concentric annular sleeves removably fitted around the post; the sleeves are pref. push fitted on to stepped dia. shoulders. integral with the central post. Each needle point is pref. of cruciform section or has in section, =1 radial wings. The needle heads are pref. covered until used by a cup-shaped cap which is a press fit on the extension. The cap can hold vaccine around the needle points. The injector can be used with central post needle head only for min. does and sleeve needle heads can be added progressively for larger doses; In all cases a single application only is necessary, so scar damage is minimised.