Details for Patent: 8,225,780

Title:	Medicament dispensing device with a multimaterial diaphragm bounding a pneumatic force chamber
Abstract:	Provided herein is a metered dose inhaler for use with a pressurized aerosol container which is preferably breath-actuated. The metered dose inhaler contains a diaphragm which includes a central disk of a first, relatively high stiffness material and a peripheral ring, coupled by a flexure of a second, relatively low stiffness material.
Inventor(s):	Holroyd; Michael (Cambridge, GB)
Assignee:	Norton Healthcare Limited (London, GB)
Filing Date:	Oct 15, 2009
Application Number:	12/579,942
Claims:	1. A diaphragm for defining a closed region within a medicament dispensing device including a main body, a sleeve movably positioned within said main body, and a spring operatively positioned in said main body to apply a preload force to said sleeve, said diaphragm comprising: a relatively rigid central disk made of a first material having a relatively high stiffness, and adapted to be affixed to an inner end of said main body of said medicament dispensing device; a peripheral attachment ring disposed about a peripheral portion of said disk and adapted to be attached to a closed end of said sleeve of said medicament dispensing device; and an annular flexure made of a second material having a relatively low stiffness, and extending between said peripheral portion of said disk and said attachment ring to thereby define a closed region between said diaphragm and said closed end of said sleeve; and wherein said annular flexure is bonded to said disk, and wherein said disk, said annular flexure and said peripheral ring form a contiguous assembly. 2. A diaphragm according to claim 1, wherein the diaphragm defines a valve port for providing fluid communication between said inner end of said main body and said closed region. 3. A diaphragm according to claim 1, wherein said peripheral ring is made of said second material and unitarily formed with said annular flexure. 4. A diaphragm according to claim 1, wherein said annular flexure is bonded to said disk along at least one bonding surface substantially parallel to a central axis of said diaphragm. 5. A diaphragm according to claim 4, wherein said at least one bonding surface comprises a continuous surface axially arranged with respect to said central axis. 6. A diaphragm according to claim 1, wherein said annular flexure is bonded to said disk along at least one bonding surface substantially traverse to a central axis of said diaphragm. 7. A diaphragm for defining a closed region within a medicament dispensing device including a main body, a sleeve movably positioned within said main body, and a spring operatively positioned in said main body to apply a preload force to said sleeve, said diaphragm comprising: a relatively rigid central disk made of a first material having a relatively high stiffness, and adapted to be affixed to an inner end of said main body of said medicament dispensing device:, a peripheral attachment ring disposed about a peripheral portion of said disk and adapted to be attached to a closed end of said sleeve of said medicament dispensing device; and an annular flexure made of a second material having a relatively low stiffness, and extending between said peripheral portion of said disk and said attachment ring to thereby define a closed region between said diaphragm and said closed end of said sleeve; said diaphragm further comprising a central portion that is made of said second material and unitarily formed with and extending radially inwardly from said annular flexure, said central portion bonded to said disk along at least one bonding surface substantially traverse to a central axis of said diaphragm; and wherein said disk, said annular flexure and said peripheral ring form a contiguous assembly. 8. A diaphragm according to claim 7, wherein said central portion is in the form of a disk. 9. A diaphragm according to claim 7, wherein said central portion is also bonded to said disk along at least one surface substantially parallel to said central axis. 10. A diaphragm according to claim 9, wherein said central portion includes at least one annular wall coaxially arranged with respect to said central axis and received within an annular groove of said disk, said annular wall bonded to said disk along the at least one surface substantially parallel to said central axis. 11. A diaphragm according to claim 7, wherein the diaphragm defines a valve port for providing fluid communication between said inner end of said main body and said closed region, and wherein said valve port passes through said central portion and said disk. 12. A method of forming and assembling a diaphragm of a medicament dispensing device comprising the steps of: forming a relatively rigid central disk from a first material having a relatively high stiffness; forming a diaphragm component from a second material having a relatively low stiffness, the diaphragm component including a central segment, an annular flexure segment extending circumferentially about a peripheral portion of the central segment, and a peripheral ring segment extending circumferentially about a peripheral portion of the annular flexure segment, wherein the peripheral ring segment is disposed about the annular flexure segment to form a substantially cylindrical and contiguous component; bonding the central disk to a mounting surface of the central portion of the diaphragm component to form the diaphragm; and positioning the diaphragm in a medicament dispensing device. 13. The method of claim 12, wherein the bonding step includes bonding the central disk to the mounting surface of the diaphragm component along at least one surface of the mounting surface that is substantially parallel to a central axis of the diaphragm. 14. The method of claim 12, wherein the bonding step includes bonding the central disk to the mounting surface of the diaphragm component along at least one surface of the mounting surface that is substantially traverse to a central axis of the diaphragm. 15. The method of claim 12, wherein the bonding step includes bonding an annular wall formed on the mounting surface to a corresponding annular groove formed on the central disk.