Claims for Patent: 7,587,988

Summary for Patent: 7,587,988

Title:	Inhaler device counter
Abstract:	Inhaler counter (20) comprising a counter housing (390), a rocker arm (200) with a pawl (210), the rocker arm being pivotally supported by the housing and arranged to perform a rocker movement in response to a linear actuation motion, a return spring (220) for resetting the rocker arm, a ratchet wheel (230) engagable with the pawl to convert the movement of the rocker arm into an incremental rotational motion of an axle arrangement (240) advancing a display means (60), the axle arrangement further comprising a back rotation prevention means (280) in the form of a spring loaded friction brake and a worm gear, the display means comprising rotatable indicator means (120) with teeth that engage the worm-gear and a stationary scale.
Inventor(s):	Bowman; Nic (Cambridge, GB), Bradshaw; Douglas (Royston Herts, GB), Sorby; Lennart (Uppsala, SE)
Assignee:	AstraZeneca AB (Sodertalje, SE)
Application Number:	11/570,747
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 7,587,988
Patent Claims:	1. An inhaler counter comprising: a ratchet wheel, a pawl, and a display, the ratchet wheel and the pawl being arranged to transform a linear actuation motion into a rotational motion that advances the display by the pawl engaging a tooth of the ratchet wheel, the pawl and ratchet wheel arranged to effect the disengagement of the pawl from the engaged tooth on the ratchet wheel by establishing abutment of the pawl and the ratchet wheel at a lever point following the engaged tooth with respect to the direction of the rotational motion of the ratchet wheel; wherein the lever point on the ratchet wheel is located on a tooth subsequent to the engaged tooth, and wherein the subsequent tooth includes a convex back surface and the pawl includes a low profile pawl counter surface that abuts the convex back surface to form the lever point. 2. An inhaler comprising: an inhaler canister; an actuator body receiving the inhaler canister, the inhaler being actuated by linear motion of the canister relative to the actuator body; and an inhaler counter according to claim 1. 3. An inhaler counter comprising: a ratchet wheel; a pawl, the ratchet wheel and the pawl being arranged for transforming a linear actuation motion into a rotational motion advancing a display by the pawl engaging a tooth of the ratchet wheel; and a friction brake preventing back rotation of the ratchet wheel, the friction brake comprising a cylindrical element and two inclined friction surfaces in V-arrangement each engaging a cylindrical surface of the cylindrical element, the cylindrical element being coupled to the rotational movement of the ratchet wheel and urged against the friction surfaces by a spring member. 4. The inhaler counter according to claim 3, wherein the friction surfaces are parallel to the axis of rotation for the cylindrical element. 5. The inhaler counter according to claim 3, wherein the angle between the friction surfaces is less than 120.degree. and greater than 60.degree.. 6. The inhaler counter according to claim 5, wherein the angle between the friction surfaces is less than 110.degree.. 7. The inhaler counter according to claim 6, wherein the angle between the friction surfaces is less than 100.degree.. 8. The inhaler counter according to claim 5, wherein the angle between the friction surfaces is greater than 75.degree.. 9. The inhaler counter according to claim 8, wherein the angle between the friction surfaces is greater than 80.degree.. 10. The inhaler counter according to claim 3, wherein the spring member applies a force on the cylindrical element in a direction essentially opposite the direction of movement of the pawl when advancing the display. 11. An inhaler counter comprising: a ratchet wheel; a pawl, the ratchet wheel and the pawl being arranged for transforming a linear actuation motion into a rotational motion advancing a display by the pawl engaging a tooth of the ratchet wheel; and a friction brake preventing back rotation of the ratchet wheel, the friction brake comprising a cylindrical element supported by two inclined friction surfaces in V-arrangement, the cylindrical element being coupled to the ratchet wheel and urged against the friction surfaces by a spring member, wherein the cylindrical element and the ratchet wheel are arranged on a common axle arrangement, and that the friction break functions as a bearing for the axle arrangement. 12. The inhaler counter according to claim 11, wherein the axle arrangement further comprises a worm-gear for driving the display, and a second bearing, and wherein the display comprises rotatable indicator with teeth that engage the worm-gear. 13. An inhaler counter comprising: a counter housing, a rocker arm with a pawl, the rocker arm being pivotally supported by the housing and arranged to perform a rocker movement in response to a linear actuation motion, a return spring for resetting the rocker arm, a ratchet wheel engagable with the pawl to convert the movement of the rocker arm into an incremental rotational motion of an axle arrangement advancing a display means, the axle arrangement further comprising a back rotation prevention means in the form of a spring loaded friction brake and a worm gear, the display means comprising rotatable indicator means with teeth that engage the worm-gear and a stationary scale. 14. The inhaler counter according to claim 13 characterized in that the pawl return spring and the friction brake spring are formed as one integral element. 15. The inhaler counter according to claim 13 characterized in that the back rotation prevention means is comprised of a cylindrical element supported by two inclined friction surfaces in V-arrangement, the cylindrical element being coupled to the rotational movement of the ratchet wheel and pawl mechanism and urged against the friction surfaces by a spring member. 16. The inhaler counter according to claim 13 characterized in that the axle arrangement, comprising the ratchet wheel, the cylindrical friction brake element and the worm gear are provided as one integral element. 17. The inhaler counter according to claim 13 characterized in that the counter housing is arranged to be attached to a non valve end of an inhaler canister. 18. The inhaler counter according to claim 13 characterized in that the counter housing comprises an opening arranged to receive a mating counter actuation protrusion formed as a part of an inhaler actuator housing, wherein the counter actuation protrusion, at actuation of the inhaler, enters the mating opening in the counter housing, engages the rocker arm, and urges the rocker arm to perform said rocker movement.