Patent ID: 8113199

Claim:
A dose counter for use with a medicament dispenser, said dose counter comprising a first count wheel arranged to rotate about a first axis of rotation, said first count wheel including count indicia and a set of primary drive teeth arranged annularly thereon for drivable rotation of the first count wheel about said first axis of rotation; a second count wheel arranged to rotate about the first axis of rotation, said second count wheel including count indicia and a set of secondary drive teeth arranged annularly thereon, and said second count wheel is arranged concentric to the first count wheel such that the respective count indicia are arranged concentrically; a kick wheel arranged to rotate about a second axis of rotation offset from the first axis of rotation, said kick wheel including a set of kick teeth arranged annularly thereon and in meshed relationship with the set of secondary drive teeth of the second count wheel such that rotary motion of the kick wheel results in rotary motion of the second count wheel; and, a drive wheel which is constantly in meshed relationship with the primary drive teeth of the first count wheel and which is adapted in use to couple with an operating mechanism of a medicament dispenser such that actuation of the operating mechanism will cause the drive wheel to rotate and to drive rotation of the first count wheel; wherein said first count wheel further includes a fixed index tooth arranged for intermittent meshing with the kick teeth of the kick wheel such that rotary motion of the kick wheel results from rotary motion of the first count wheel only when said intermittent meshing occurs; wherein the dose counter has a display region through which the count indicia of the first and second count wheels are rotatable; wherein the second count wheel comprises a shutter which is movable to a shuttering position in which it shutters the display region; wherein the dose counter is configured and arranged to display a count sequence in the display region with the count indicia and to cause the shutter to move to its shuttering position at the end of the count sequence; and wherein the dose counter is configured and arranged so that drive transmission from the first count wheel to the second count wheel through the kick wheel is disengaged when the shutter is in the shuttering position to keep the shutter in the shuttering position when the drive wheel drives further rotation of the first count wheel.