GB2515038A — Injection device

USPTO Abstract

An injection device having a release or locking mechanism, such as a retractable sleeve for pressing against the skin of a user, has tactile and audible feedback signalling means to indicate to a user when the release mechanism is moved from a first position in which injection delivery is impeded to a second position in which a trigger may be actuated. A variation in the force required to move the release mechanism from the first to the second position, represented by a non-linear profile of force required with distance, may be achieved by resilient arms 201 moving along a curved or undulating camming surface 210 with bumps 212, or by a changing friction surface, or by using a pair of resilient arms or springs. An audible signal may result from contact between components or the completion of an electrical circuit producing an electronic tone, beep or ringing of a bell.