Claims for Patent: 4,668,218

Summary for Patent: 4,668,218

Title:	Indicating means for a dosage dispensing device
Abstract:	An indicating means in a dosage dispensing device for medicaments, particularly a dosage inhaler which indicates a number of dosages administered from the dosage dispensing device. The indicating means includes a rotatable disc (1) having apertures (2) passing therethrough which can be filled with a medicament in particle form. By rotating the disc the apertures can be brought into an air channel or duct (3) through which air is inhaled. The rotatable disc has associated with a central portion a spiral groove or ridge (4) which can engage with peripheral teeth (8) on a toothed wheel (6), such that rotation of the disc (1) results in rotation of the toothed wheel and the toothed wheel is provided with one or more markings (9) which are visible from outside the dosage inhaler upon rotating the disc a predetermined number of times.
Inventor(s):	Virtanen; Risto (Nurmij/a/ rvi, FI)
Assignee:	Aktiebolaget Draco (SE)
Application Number:	06/850,959
Patent Claims:	1. An indicating means for a dosage dispensing device for medicaments, particularly a dosage inhaler, said means comprising a rotatable disc; apertures passing through said disc, said apertures being fillable with a medicament in particle form; an airduct or channel through which air can be inhaled; means for rotating said disc effective to bring at least one of said apertures into register with said airduct or channel; a spiral groove or ridge associated with a central portion of said disc; a toothed wheel; peripheral teeth on said wheel extending transverse to and engaging with said spiral groove or ridge, whereby rotation of said disc results in rotation of said toothed wheel; and one or more markings on said toothed wheel which are visible from outside the dosage inhaler upon rotation of the disc a predetermined number of times. 2. An indicating means as claimed in claim 1, wherein said toothed wheel extends in a diametral plane of the disc and the spiral groove or ridge is arranged to draw the teeth of the toothed wheel in towards the center of the disc when the disc is rotated in its intended direction of rotation. 3. An indicating means as claimed in claim 2, wherein the outermost part of the spiral groove or ridge is located at a shorter radial distance from the center of the disc than the projection of the axis of the shaft of the toothed wheel on the disc. 4. An indicating means as claimed in claim 1, and further comprising latching means arranged for resilient engagement between the teeth of the toothed wheel. 5. An indicating means as claimed in claim 1, further comprising a window positioned whereby each marking is arranged to be brought into view in said window on rotation of said disc. 6. A dosage inhaler comprising a medicament storage space; a rotatable disc rotatable adjacent said storage space; apertures passing through said disc, said apertures being fillable with a medicament in particle form from said storage space; an airduct or channel through which air can be inhaled; means for rotating said disc effective to bring at least one of said apertures into register with said airduct or channel; a spiral groove or ridge associated with a central portion of said disc; a toothed wheel; peripheral teeth opposite wheel extending transverse to and engaging said spiral groove or ridge, whereby rotation of said disc results in rotation of said tooth wheel; and one or more markings on said tooth wheel which are visible from outside the dosage inhaler upon rotation of the disc a predetermined number of times. 7. A dosage inhaler as claimed in claim 6, wherein said toothed wheel extends in a diametral plane of the disc and the spiral groove or ridge is arranged to draw the teeth of the toothed wheel in towards the center of the disc when the disc is rotated in its intended direction of rotation. 8. A dosage inhaler as claimed in claim 6, wherein the outer most part of the spiral groove or ridge is located at a shorter radial distance from the center of the disc than the projection of the axis of the shaft of the toothed wheel on the disc. 9. A dosage inhaler as claimed in claim 6, and further comprising a latching means arranged for resilient engagement between the teeth of the toothed wheel. 10. A dosage inhaler as claimed in claim 6, and further comprising a window positioned whereby each marking is arranged to be brought into view of said window on rotation of said disc.