Tensioning mechanism for peeling a sheet from a blister strip for use in a dry powder inhaler

Abstract

An inhalation device for delivering dry powder medicament from at least one blister strip, the inhalation device including an actuator for operating a dispensing mechanism of the inhalation device, and a tensioning mechanism for use in the inhalation device configured to maintain consistent tension in the blister strip over the life of the device.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Patent Application No. 63 / 483,383, filed February 6, 2023, the entire contents of which are incorporated herein by reference for all purposes.

[0002]

[0002] The present invention relates generally to inhalation devices, and more particularly to tensioning mechanisms for use in inhalation devices configured to dispense dry powder medicaments from one or more blister strips. [Background technology]

[0003] Medication can be administered to a patient by inhalation using a dry powder dispenser device. Such devices are often used for the treatment and prevention of respiratory diseases, including, but not limited to, asthma and chronic obstructive pulmonary disease (COPD). The medication carrier may include a blister strip containing several individual doses of powdered medication. Such devices typically include a mechanism, such as a puncturing means, for accessing the medication doses by opening one or more blister pockets. The powdered medication can then be accessed by the device and inhaled through the device by the user.

[0004]

[0004] For inhalers or inhalation devices of the types described above to function properly, it is necessary to maintain consistent tension in the blister strip over the life of the device. Embodiments of the present invention relate to a mechanism for maintaining consistent tension in the blister strip in a dry powder inhaler device. Summary of the Invention

[0005] According to a first embodiment of the present disclosure, the present disclosure provides a tensioning mechanism for peeling a sheet from a blister strip for use in a dry powder inhaler device. The tensioning mechanism includes a base, a nut including at least one rib that engages a cam surface, a compression spring longitudinally adjacent to the nut, and a take-up hub disposed around the nut and the compression spring. The nut is disposed between the take-up hub and the base and is coupled to both the take-up hub and the base. The take-up hub is rotationally constrained to the nut and configured to rotate relative to the base. When the base is rotationally driven, the nut interacts with the compression spring and the cam surface to apply a torque to the take-up hub. When the take-up hub applies an opposing torque to the nut, the nut moves along the cam surface, axially compressing the compression spring.

[0006] In one aspect of the first embodiment, in combination with any other aspect herein, the present disclosure provides that the take-up hub includes a hook on an outer surface of the take-up hub, the hook configured to be attached to an end of the sheet of blister strip such that rotation of the take-up hub causes the sheet of blister strip to wind around the take-up hub.

[0007] In one aspect of the first embodiment, in combination with any other aspect herein, the present disclosure provides that the take-up hub is axially constrained relative to the base.

[0008]

[0008] In one aspect of the first embodiment, in combination with any other aspect of the present specification, the present disclosure provides that the winding hub is axially constrained relative to the base via a bayonet connection between the base and the winding hub.

[0009]

[0009] In one aspect of the first embodiment, in combination with any other aspect of the present specification, the present disclosure provides that the bayonet connection includes a radial extension of the base and an internal flange of the winding hub, the internal flange including an axial slot configured to allow passage of the radial extension.

[0010]

[0010] In one aspect of the first embodiment, in combination with any other aspect of the present specification, the present disclosure provides that the base includes a plurality of gear teeth integrally formed or fixed to the outer circumferential surface of the base.

[0011] In one aspect of the first embodiment, in combination with any other aspect herein, the present disclosure provides that the cam surface includes alternating sections of vertical and inclined surfaces.

[0012]

[0012] In one aspect of the first embodiment, in combination with any other aspect herein, the present disclosure provides that the at least one rib includes a plurality of circumferentially spaced ribs.

[0013] In one aspect of the first embodiment, in combination with any other aspect herein, the present disclosure provides that the cam surface is integrally formed with or fixed to a portion of the base, at least one rib projects radially inward from an inner peripheral surface of the nut, and the take-up hub is rotationally locked to the nut.

[0014] In one aspect of the first embodiment, in combination with any other aspect herein, the present disclosure provides that a compression spring extends between the take-up hub and the nut.

[0015]

[0015] In one aspect of the first embodiment, in combination with any other aspect of the present specification, the present disclosure provides that the take-up hub is rotationally locked to the nut via an outwardly extending rib that protrudes radially outward from the outer circumferential surface of the nut and is received within an axial slot in the take-up hub.

[0016]

[0016] In one aspect of the first embodiment, in combination with any other aspect herein, the present disclosure provides that the cam surface has a first outer diameter and the compression spring has a second outer diameter, the first outer diameter being larger than the second outer diameter.

[0017] In one aspect of the first embodiment, in combination with any other aspect herein, the present disclosure provides that the cam surface is integrally formed with or fixed to a portion of the take-up hub, at least one rib projects radially outward from an outer peripheral surface of the nut, and the base is rotationally locked to the nut.

[0018] In one aspect of the first embodiment, in combination with any other aspect herein, the present disclosure provides a shaft extending from a base, the shaft being integrally formed with or secured to the base, the base being rotationally locked to the nut via an inwardly extending rib projecting radially inward from an inner periphery of the nut and received in an axial slot in the shaft.

[0019] In one aspect of the first embodiment, in combination with any other aspect herein, the present disclosure provides that a compression spring extends between the nut and the base.

[0020] According to a second embodiment of the present disclosure, the present disclosure provides a dry powder inhaler including a housing, an indexing spool, a take-up hub, and a tensioning mechanism. The housing receives at least one blister strip for use in the dry powder inhaler, the blister strip including a bottom sheet and a top sheet releasably secured to the bottom sheet. The indexing spool is rotatably driven in a first direction, and an outer surface of the indexing spool receives the bottom sheet of the blister strip. The take-up hub is rotatably driven in either the first direction or a second opposite direction, and an outer surface of the take-up hub is attached to an end of the top sheet, and rotation of the take-up hub causes the top sheet to wind around the outer surface of the take-up hub. The tensioning mechanism includes a slider and at least one spring attached to the slider. The tensioning mechanism is coupled to the housing to permit axial movement of the slider relative to the housing along a predetermined path. The slider is configured to receive an intermediate portion of the top sheet of the blister strip, the intermediate portion of the top sheet being disposed between the indexing spool and the take-up hub, and increasing tension along the top sheet of the blister strip results in axial movement of the slider along a predetermined path, which axially compresses or expands the spring to reduce the tension along the top sheet of the blister strip.

[0021]

[0021] In one aspect of the second embodiment, in combination with any other aspect of the present specification, the present disclosure provides that a first end of the spring is attached to the slider and a second end of the spring is attached to the housing.

[0022]

[0022] In one aspect of the second embodiment, in combination with any other aspect herein, the present disclosure provides that the predetermined path is formed by a recess in an inner surface of the housing.

[0023]

[0023] In one aspect of the second embodiment, in combination with any other aspect of the present specification, the present disclosure provides that the spring is a compression spring, and the compression spring is biased to push the slider away from each of the index spool and the take-up hub.

[0024]

[0024] In one aspect of the second embodiment, in combination with any other aspect of the present specification, the present disclosure provides that axial compression of the compression spring brings the slider closer to each of the index spool and the take-up hub.

[0025] In one aspect of the second embodiment, in combination with any other aspect herein, the present disclosure provides that the predetermined path is linear.

[0026] In one aspect of the second embodiment, in combination with any other aspect herein, the present disclosure provides that the at least one spring includes a single spring.

[0027] In one aspect of the second embodiment, in combination with any other aspect herein, the present disclosure provides that the at least one spring includes two springs.

[0028] In one aspect of the second embodiment, in combination with any other aspect herein, the present disclosure provides that the winding hub is rotationally driven in a first direction.

[0029] In one aspect of the second embodiment, in combination with any other aspect herein, the present disclosure provides that the take-up hub is rotationally driven in a second, opposite direction.

[0030]

[0030] In one aspect of the second embodiment, in combination with any other aspect of the present specification, the present disclosure provides that at least one spring is a compression spring, and axial movement of the slider causes the spring to compress axially, reducing the tension along the upper sheet of the blister strip.

[0031]

[0031] In one aspect of the second embodiment, in combination with any other aspect of the present specification, the present disclosure provides that at least one spring is a tension spring, and axial movement of the slider causes the spring to extend axially, reducing the tension along the upper sheet of the blister strip.

[0032] According to a third embodiment of the present disclosure, the present disclosure provides a dry powder inhaler including a housing, an indexing spool, a take-up hub, and a tensioning mechanism. The housing receives at least one blister strip for use in the dry powder inhaler, the blister strip including a bottom sheet and a top sheet releasably secured to the bottom sheet. The housing includes a curved slot in an inner surface of the housing and a pin extending radially from the inner surface of the housing, the pin being disposed adjacent to a first end of the curved slot and secured to the housing. The indexing spool is rotationally driven in a first direction, and an outer surface of the indexing spool receives the bottom sheet of the blister strip. The take-up hub is rotationally driven in a second, opposite direction. The outer surface of the take-up hub is attached to an end of the top sheet, and rotation of the take-up hub causes the top sheet to wind around the outer surface of the take-up hub. The take-up hub is coupled to the housing to allow movement of the take-up hub relative to the housing along the curved slot. The tensioning mechanism includes at least one spring coupled to the take-up hub. A first end of the spring is fixed to the housing, and a second end of the spring is coupled to the take-up hub. A pin is configured to receive an intermediate portion of the upper sheet of the blister strip, the intermediate portion of the upper sheet extending between the index spool and the take-up hub. An increase in tension along the upper sheet of the blister strip causes the take-up hub to move along a curved slot in the housing, and the movement of the take-up hub axially deforms the spring, reducing the tension along the upper sheet of the blister strip.

[0033] In one aspect of the third embodiment, in combination with any other aspect herein, the present disclosure provides that the at least one spring is a tension spring.

[0034]

[0034] In one aspect of the third embodiment, in combination with any other aspect herein, the present disclosure provides that the tensioning mechanism includes a bracket having a first end coupled to allow relative rotation of the index spool with respect to the bracket, a second end attached to the second end of the spring, and an intermediate portion coupled to the take-up hub to allow relative rotation of the take-up hub with respect to the bracket.

[0035] In one aspect of the third embodiment, in combination with any other aspect herein, the present disclosure provides that the bracket is allowed to rotate relative to the housing.

[0036] In one aspect of the third embodiment, in combination with any other aspect herein, the present disclosure provides that a tension spring is biased to position the take-up hub at a first end of the curved slot and at a second end of the curved slot opposite the pin. Movement of the take-up hub toward the pin axially stretches the tension spring, reducing tension along the top sheet of the blister strip.

[0037]

[0037] In one aspect of the third embodiment, in combination with any other aspect herein, the present disclosure provides that the tension spring is aligned with the centerline of the upper seat.

[0038] In one aspect of the third embodiment, in combination with any other aspect herein, the present disclosure provides that the curved slot is concentric with the axis of rotation of the indexing spool.

[0039] In one aspect of the third embodiment, in combination with any other aspect herein, the present disclosure provides that the at least one spring is a torsion spring.

[0040]

[0040] In one aspect of the third embodiment, in combination with any other aspect herein, the present disclosure provides that the at least one spring includes a first torsion spring and a second torsion spring, the first torsion spring configured to act on a first side of the winding hub and the second torsion spring configured to act on a second, opposite side of the winding hub.

[0041]

[0041] In one aspect of the third embodiment, in combination with any other aspect herein, the present disclosure provides that a first leg of the torsion spring is fixed to an inner surface of the housing and a second leg of the torsion spring is coupled to the take-up hub so as to move in conjunction with the take-up hub along a curved slot.

[0042]

[0042] In one aspect of the third embodiment, in combination with any other aspect herein, the present disclosure provides that the body of the torsion spring is disposed concentrically with the axis of rotation of the indexing spool.

[0043]

[0043] In one aspect of the third embodiment, in combination with any other aspect of the present specification, the present disclosure provides that a torsion spring is biased to position the take-up hub at a first end of the curved slot and at a second end of the curved slot opposite the pin, and movement of the take-up hub toward the pin twists the torsion spring to reduce tension along the upper sheet of the blister strip.

[0044] The foregoing and other features and advantages of the present invention will become apparent from the following description of embodiments of the invention, as illustrated in the accompanying drawings. The accompanying drawings, which are incorporated in and form a part of this specification, further serve to explain the principles of the invention and to enable one skilled in the art to make and use the invention. The drawings are not to scale. [Brief explanation of the drawings]

[0045] [Figure 1A]1 is a front view of an inhalation device according to an embodiment of the present invention, with the mouthpiece cover of the inhalation device in a closed position. [Figure 1B] 1B is a rear view of the inhalation device of FIG. 1A, with the mouthpiece cover of the inhalation device in a closed position. [Figure 1C] 1B is a front view of the inhalation device of FIG. 1A, with the mouthpiece cover of the inhalation device in an open position. [Figure 1D] 1A-1C is a graph illustrating an estimated actuation force profile (dotted line) for an inhalation device and mouthpiece cover as depicted in Figures 1A-1C compared with an estimated actuation force profile (solid line) for an inhalation device in which the dispensing mechanism is not actuated during the initial period of movement of the mouthpiece cover. [Figure 2] FIG. 1B is a perspective view of two blister strips for use in the inhalation device of FIG. 1A. [Figure 3A] 1B is a front view of the inhaler device of FIG. 1A, with the mouthpiece cover of the inhaler device in an open position and the housing of the inhaler device removed for illustrative purposes only. [Figure 3B] 1B is a cross-sectional perspective view of a portion of the inhalation device of FIG. 1A illustrating a portion of the airflow path through the inhalation device of FIG. 1A. [Figure 4] 1B is a perspective view of the manifold of the inhalation device of FIG. 1A, with the manifold removed from the inhalation device for illustrative purposes only. [Figure 4A] FIG. 5 is a cross-sectional view taken along line AA in FIG. [Figure 5] 1B is a perspective view of the manifold of FIG. 4 positioned adjacent to the inlet vent of the housing of the inhalation device of FIG. 1A. [Figure 6] 1B is another perspective view of the manifold of the inhalation device of FIG. 1A, with the manifold removed from the inhalation device for illustrative purposes only. [Figure 7] 1B is a schematic diagram illustrating the airflow path through the manifold of the inhalation device of FIG. 1A. [Figure 8] 1B is a schematic flow chart illustrating the airflow path through the manifold of the inhalation device of FIG. 1A. [Figure 9A]1B is a front view of the inhaler device of FIG. 1A, with the mouthpiece cover of the inhaler device in an open position and a portion of the housing of the inhaler device removed for illustrative purposes only. [Figure 9B] 1B is a rear view of the inhalation device of FIG. 1A, with the mouthpiece cover and housing of the inhalation device removed for illustrative purposes only. [Figure 10] FIG. 1B is a front view of the ratchet mechanism of the inhaler device of FIG. 1A, with the ratchet gear removed from the inhaler device for illustrative purposes only. [Figure 10A] 11 illustrates the ratchet mechanism of FIG. 10 when the mouthpiece cover is in a closed position. [Figure 10B] 11 illustrates the ratchet mechanism of FIG. 10 when the mouthpiece cover is in the open position. [Figure 11] 1B is a perspective view of a portion of the mouthpiece cover and dispensing subassembly of the inhalation device of FIG. 1A, with the mouthpiece cover and dispensing subassembly removed from the inhalation device for illustrative purposes only. [Figure 12A] 1B is a perspective view of a counter subassembly of the inhalation device of FIG. 1A, the counter subassembly being removed from the inhalation device for illustrative purposes only. [Figure 12B] FIG. 12B is a front view of the counter subassembly of FIG. 12A. [Figure 12C] 12B is a cross-sectional view of the counter subassembly of FIG. 12A taken along line CC of FIG. 12B. [Figure 12D] 12C is a cross-sectional view of the counter subassembly of FIG. 12A taken along line DD of FIG. 12C. [Figure 13A] 1B is a schematic diagram of the tensioning mechanism of the inhalation device of FIG. 1A, the tensioning mechanism shown at the beginning of the device's life. [Figure 13B] 1B is a schematic diagram of the tensioning mechanism of the inhalation device of FIG. 1A, the tensioning mechanism shown near the end of the device's life. [Figure 14A] 1B is a perspective view of the tensioning mechanism of the inhalation device of FIG. 1A, with the tensioning mechanism removed from the inhalation device for illustrative purposes only. [Figure 14B] FIG. 14B is a cross-sectional view of the tensioning mechanism of FIG. 14A. [Figure 14C] FIG. 14B is a cross-sectional view of the tensioning mechanism of FIG. 14A. [Figure 14D] FIG. 14B is a perspective exploded view of the base and nut of the tensioning mechanism of FIG. 14A. [Figure 14E] 14B is a series of cross-sectional views of the tensioning mechanism of FIG. 14A illustrating the movement of the nut during operation of the inhalation device. [Figure 15A] 1B is a cross-sectional view of a tensioning mechanism according to another embodiment of the present invention for use in the inhalation device of FIG. 1A, the tensioning mechanism being removed from the inhalation device for illustrative purposes only. [Figure 15B] FIG. 15B is a perspective view of the tensioning mechanism of FIG. 15A, with the hub of the tensioning mechanism removed for illustrative purposes. [Figure 16A] 1B is a cross-sectional view of a tensioning mechanism according to another embodiment of the present invention for use in the inhalation device of FIG. 1A, the tensioning mechanism being removed from the inhalation device for illustrative purposes only. [Figure 16B] FIG. 16B is a perspective view of the tensioning mechanism of FIG. 16A, with the hub of the tensioning mechanism removed for illustrative purposes. [Figure 17A] 1B is a cross-sectional view of a tensioning mechanism according to another embodiment of the present invention for use in the inhalation device of FIG. 1A, the tensioning mechanism being removed from the inhalation device for illustrative purposes only. [Figure 17B] FIG. 17B is a perspective view of the tensioning mechanism of FIG. 17A, with the hub of the tensioning mechanism removed for illustrative purposes. [Figure 18] 1B is a side view of a tensioning mechanism according to another embodiment of the present invention for use in the inhalation device of FIG. 1A, the tensioning mechanism being removed from the inhalation device for illustrative purposes only. [Figure 19A] FIG. 19 is a side view of the tensioning mechanism of FIG. 18, the tensioning mechanism being in a first position. [Figure 19B] FIG. 19 is a side view of the tensioning mechanism of FIG. 18, the tensioning mechanism being in a second position. [Figure 20]19 is a graph of performance characteristics of the tensioning mechanism of FIG. 18. [Figure 21] 1B is a side view of a tensioning mechanism according to another embodiment of the present invention for use in the inhalation device of FIG. 1A, the tensioning mechanism being removed from the inhalation device for illustrative purposes only. [Figure 22] FIG. 22 is a side view of the tensioning mechanism of FIG. 21. [Figure 23A] FIG. 22 is a side view of the tensioning mechanism of FIG. 21, the tensioning mechanism being in a first position. [Figure 23B] FIG. 22 is a side view of the tensioning mechanism of FIG. 21, the tensioning mechanism being in a second position. [Figure 24] 1B is a side view of a tensioning mechanism according to another embodiment of the present invention for use in the inhalation device of FIG. 1A, the tensioning mechanism being removed from the inhalation device for illustrative purposes only. [Figure 25] FIG. 25 is an opposite side view of the tensioning mechanism of FIG. 24. [Figure 26A] 1B is a perspective view of a base of a tensioning mechanism according to another embodiment of the present invention for use in the inhalation device of FIG. 1A, the tensioning mechanism being removed from the inhalation device for illustrative purposes only. [Figure 26B] FIG. 26B is a perspective view of the hub of the tensioning mechanism of FIG. 26A, with the hub removed from the inhalation device for illustrative purposes only. [Figure 26C] FIG. 26B is a top view of the tensioning mechanism of FIG. 26A with its bayonet connection in an open or unlocked position. [Figure 26CC] FIG. 26D is a cross-sectional view of FIG. 26C. [Figure 26D] FIG. 26B is a top view of the tensioning mechanism of FIG. 26A with its bayonet connection in a closed or locked position. [Figure 26DD] FIG. 26D is a cross-sectional view of FIG. [Figure 26E] FIG. 26B is a perspective view of the nut of the tensioning mechanism of FIG. 26A, with the nut removed from the inhalation device for illustrative purposes only. [Figure 26F]FIG. 26B is another perspective view of the hub of the tensioning mechanism of FIG. 26A, with the hub removed from the inhalation device for illustrative purposes only. [Figure 26G] FIG. 26B is a perspective view of a nesting fixture configured for use with the tensioning mechanism of FIG. 26A. [Figure 26H] FIG. 26B is a perspective view of the base of the tensioning mechanism of FIG. 26A, with the base removed from the inhalation device for illustrative purposes only. [Figure 26I] 26H disposed on the nesting fixture of FIG. 26F. FIG. [Figure 26J] 26H disposed on the nested fixture of FIG. 26F with the nut disposed thereon prior to rotation of the nut by the hub. FIG. [Figure 26K] 26H disposed on the nested fixture of FIG. 26F with the nut disposed thereon after rotation of the nut by the hub. FIG. [Figure 26L] FIG. 26B is a perspective view of the nut and base of the tensioning mechanism of FIG. 26A at an end of device life condition, where an audible click is output by the tensioning mechanism. [Figure 26M] FIG. 26B is a perspective view of the nut and base of the tensioning mechanism of FIG. 26A at the beginning of the device's life condition. [Figure 26N] FIG. 26B is another perspective view of the nut and base of the tensioning mechanism of FIG. 26A at an end of device life condition, with the lockout mechanism of the tensioning mechanism engaged. [Figure 27A] FIG. 26B is a perspective view of another embodiment of a lockout mechanism for use with the tensioning mechanism of FIGS. 26A-26N. [Figure 27B] FIG. 26B is a perspective view of another embodiment of a lockout mechanism for use with the tensioning mechanism of FIGS. 26A-26N. [Figure 27C] FIG. 26B is a perspective view of another embodiment of a lockout mechanism for use with the tensioning mechanism of FIGS. 26A-26N. [Figure 27D] FIG. 27D is another perspective view of the lockout mechanism of FIG. 27C. DETAILED DESCRIPTION OF THE INVENTION

[0046]

[0111] Specific embodiments of the present invention will now be described with reference to the drawings, where like reference numbers indicate identical or functionally similar elements. The following detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. While the invention has been described in the context of testing stent-graft devices, the invention may also be used to test other tubular prostheses for which it may be useful. Furthermore, there is no intention to be bound by any expressed or implied theory presented in the preceding technical field, background, brief summary, or the following detailed description.

[0047]

[0112] Embodiments of the present invention relate to inhalation devices configured to deliver powdered medicament from at least one blister strip, and more particularly to a tensioning mechanism for maintaining consistent tension in the blister strip over the life of the device. While the tensioning mechanism described herein is shown in an inhalation device configured to deliver powdered medicament from two blister strips simultaneously, it may also be utilized in inhalation devices configured to deliver powdered medicament from a single blister strip or three or more blister strips.

[0048]

[0113] 1A, 1B, and 1C illustrate an inhalation device 100 according to one embodiment of the present invention. The inhalation device 100 includes a housing 102 and a mouthpiece cover 108. The housing 102 includes a display window 104 that displays a number indicating the number of doses remaining in the inhalation device 100. The housing 102 also includes a plurality of openings or inlet vents 106 formed through a sidewall of the housing 102. As described in more detail herein, air from outside the inhalation device 100 is drawn into the interior of the inhalation device 100 through the inlet vents 106 when a user inhales through a mouthpiece 110. In FIGS. 1A and 1B, the mouthpiece cover 108 of the inhalation device 100 is in a closed position, with the mouthpiece cover 108 covering or extending over the mouthpiece 110. In FIG. 1C, the mouthpiece cover 108 is in an open position, such that the mouthpiece 110 is exposed and available to the user. A user can inhale powdered medicament through mouthpiece 110 only when mouthpiece cover 108 is in the open configuration. Mouthpiece 110 includes a central exit or opening 112 that allows delivery of powdered medicament contained within inhalation device 100 to a user via inhalation.

[0049]

[0114] 1A and 1B, the mouthpiece 110 and the inlet vent 106 are covered by the mouthpiece cover 108. When a user wishes to inhale a medication dose from the inhalation device 100, the mouthpiece cover 108 is moved from the closed position of FIGS. 1A and 1B to the open position of FIG. 1C. In the open position, the mouthpiece cover 108 is rotated or moved relative to the housing 102 so that the mouthpiece 110 and the inlet vent 106 are fully exposed and are no longer covered by any portion of the mouthpiece cover 108. Because the user is instructed to cover the central opening 112 of the mouthpiece 110 with their mouth during inhalation of a powdered medication, the mouthpiece cover 108 protects the mouthpiece 110 when the inhalation device 100 is not in use, preventing contamination of the airflow passageway of the inhalation device 100 with undesirable particles that could otherwise adversely affect the user experience and / or dose delivery. As described in more detail herein, movement of mouthpiece cover 108 from the closed position to the open position activates a dispensing mechanism within inhalation device 100 to make a medication dose available for inhalation, and also activates a counter mechanism within inhalation device 100 to decrement by one the number of remaining doses indicated in viewing window 104. Thus, mouthpiece cover 108 functions to protect central opening 112 of mouthpiece 110 and also operates the dispensing and counter mechanisms of inhalation device 100. A single operational step, namely, movement of mouthpiece cover 108, is all that is required by the user to activate inhalation device 100 for each dose.

[0050]

[0115] In one embodiment, the mouthpiece cover 108 may be rotated 85° to 105° by the user to expose the mouthpiece 110 and inlet vent 106. When designing the inhalation device 100, it is important to ensure that the force required to actuate the mouthpiece cover 108 is low enough to allow easy operation by users of various abilities. Generally, the longer the travel distance of the mouthpiece cover 108, the more favorable mechanical advantage is achieved in the inhalation device's dispensing mechanism, resulting in a lower actuation force required to rotate the mouthpiece cover 108 and actuate the inhalation device 100 for each dose. However, from an ergonomic standpoint, a shorter travel distance of the mouthpiece cover 108 avoids the need for the user to change grip during actuation. The shorter the travel distance of the mouthpiece cover 108, the smaller the area of ​​the housing 102 traversed by the mouthpiece cover 108, and therefore the greater the area of ​​the housing 102 for the user to grip during actuation. A shorter travel for the mouthpiece cover 108 also allows more space for other features of the inhalation device 100 and / or allows the size of the inhalation device 100 to be minimized. In one embodiment, a cover travel of 90-100 degrees may provide an optimal balance between the factors discussed above. As shown in Figures 1A-1C, the housing 102 has an integral flange or step 102A formed thereon that controls or limits the rotational movement of the mouthpiece cover 108 to a desired range.

[0051]

[0116] The force profile over the movement of the mouthpiece cover 108 affects the user experience and tactile feedback provided by the inhalation device 100. Maintaining a relatively consistent or constant actuation force over the movement of the mouthpiece cover 108 is also desirable to avoid incorrect use or confusion. Using the full movement of the mouthpiece cover 108 to operate the dispensing mechanism is expected to provide a more consistent actuation force profile and help reduce the risk of misuse of the inhalation device 100. For example, in inhalation devices other than the present invention, in which the dispensing mechanism is not actuated during the initial period of mouthpiece cover movement, the actuation force is relatively low during this initial period. Once the dispensing mechanism is actuated, the mouthpiece cover actuation force increases. Thus, in inhalers other than the present invention, the actuation force of the mouthpiece cover increases significantly midway through the full movement of the mouthpiece cover, and a user may mistakenly perceive this change as tactile feedback suggesting that the mouthpiece cover is sufficiently open to take a dose. In other words, a non-constant actuation force profile may confuse a user regarding tactile feedback, potentially leading to incorrect use of the device. 1D illustrates an estimated actuation force profile, represented by the dashed line, for an inhalation device 100 according to embodiments herein having a mouthpiece cover 108, compared to an estimated actuation force profile, represented by the solid line, for an inhalation device in which the dispensing mechanism is not activated for the initial period of mouthpiece cover movement, as described in the previous example. When the dispensing mechanism is not activated at the beginning of mouthpiece movement, there is a step in the actuation force profile, represented by the solid line in FIG. 1D. Conversely, when the dispensing mechanism is activated at the beginning of mouthpiece movement, as in inhalation device 100, the actuation force is approximately constant or consistent, with a lower peak actuation force, as represented by the dashed line in FIG. 1D.

[0052]

[0117] The inhalation device 100 is configured to simultaneously dispense dry powder medicament from two blister strips. More specifically, referring to FIG. 2 , a first blister strip 160A and a second blister strip 160B are shown. The inhalation device 100 described herein is configured to simultaneously dispense medicament from each of the first blister strip 160A and the second blister strip 160B. Each blister strip 160A, 160B includes a bottom sheet 162A, 162B, respectively, defining a series or plurality of individual blisters or pockets 164A, 164B thereon. Each pocket 164A, 164B is configured to contain a dose or portion of a dry powder or powdered medicament 168A, 168B to be inhaled by a user. In one embodiment, powdered medicament 168A is a different medicament from powdered medicament 168B, such that inhalation device 100 is configured to simultaneously deliver two different powdered medicaments to a user. Top sheets 166A, 166B are hermetically bonded or sealed to bottom sheets 162A, 162B, respectively, to close pockets 164A, 164B, and function as lids for pockets 164A, 164B to hold powdered medicaments 168A, 168B therein. The hermetic sealing of top sheets 166A, 166B is such that bottom sheets 162A, 162B and top sheets 166A, 166B can be peeled apart to open or uncover pockets 164A, 164B for access to powdered medicaments 168A, 168B therein. Each of first blister strip 160A and second blister strip 160B is sufficiently flexible to be wound into a roll.

[0053]

[0118] As described in more detail herein, when the dispensing mechanism of inhalation device 100 is actuated via movement of mouthpiece cover 108, top sheets 166A, 166B of blister strips 160A, 160B are peeled away from bottom sheets 162A, 162B of blister strips 160A, 160B, respectively, to release or open pockets 164A, 164B of each blister strip, thereby exposing powdered medicament 168A, 168B disposed therein. Upon inhaling through mouthpiece 110, the user simultaneously inhales powdered medicament 168A, 168B from the opened pockets 164A, 164B of blister strips 160A, 160B, respectively. Thus, the user receives a metered dose of medicament powder, with different medicament powders from the opened pockets 164A, 164B of blister strips 160A, 160B each constituting a respective dose portion. Each blister strip 160A, 160B may be the same size and / or contain the same dose (e.g., volume or mass) of powdered medicament, or may be different sizes and / or contain different doses of powdered medicament.

[0054]

[0119] 3A is a front view of inhalation device 100 with mouthpiece cover 108 in an open position and housing 102 removed for illustrative purposes only. Inhalation device 100 includes a manifold 114 for internally directing airflow to pick up powdered medicaments 168A, 168B from blister strips 160A, 160B, respectively, through mouthpiece 110 and deliver them to a user. Manifold 114 is in fluid communication with mouthpiece 110 such that powdered medicaments 168A, 168B may be delivered to a user through a central opening 112 of mouthpiece 110. In addition to manifold 114, inhalation device 100 also includes a dispensing subassembly or mechanism 120, a counter subassembly or mechanism 134, and tensioning subassemblies or mechanisms 151A, 151B. When assembled, manifold 114 , dispensing subassembly 120 , counter subassembly 134 , and each of tensioning mechanisms 151 A, 151 B reside or are disposed within housing 102 .

[0055]

[0120] The operation of the manifold 114 is introduced herein with reference to FIG. 3B. The manifold 114 defines an airway through the inhalation device 100. The manifold 114 fluidly connects the mouthpiece 110 to the first blister strip 160A and the second blister strip 160B. FIG. 3B is a cross-sectional view through the manifold to illustrate the airflow path through the manifold 114 for loading the medicament 168B of the second blister strip 160B. As will be described with respect to FIGS. 10-14, the manifold 114 also defines an airflow path therein for loading the medicament 168A of the first blister strip 160A.

[0056]

[0121] During use, the mouthpiece cover 108 is rotated by a user to expose the mouthpiece 110 and the inlet vent 106. Internally, within the inhalation device 100, rotating the mouthpiece cover 108 exposes the powdered medicaments 168A, 168B within the pockets 164A, 164B of each of the first blister strip 160A and second blister strip 160B, respectively. To access the powdered medicaments 168A, 168B within the open pockets 164A, 164B, the user breathes in or inhales through the mouthpiece 110. The user covers the central opening 112 of the mouthpiece 110 with their mouth and, by inhaling, creates a pressure differential between the inlet vent 106 and the central opening 112, moving air through the manifold 114. The pressure differential causes external air (i.e., air from outside the inhalation device 100) to enter the inhalation device 100 through the inlet vent 106, pass through the open pockets 164A, 164B, and exit the inhalation device 100 through the central opening 112. The airflow path defined by the manifold 114 is designed so that, as a user inhales, the exposed powdered medicament 168A, 168B in the open pockets 164A, 164B is picked up by the air stream and delivered to the user as a combined oral inhalation medicament dose. Thus, the user can inhale one dose portion from each blister strip 160A, 160B simultaneously.

[0057]

[0122] Manifold 114 is configured to direct the inhalation airflow in various ways to achieve suitable airflow characteristics for effective delivery of the powdered medicament. More specifically, as shown in FIG. 3B, the geometry of manifold 114 directs a portion of the inhalation airflow into and out of open pocket 164B of second blister strip 160B (labeled by dotted line 199 in FIG. 3B), while another portion of the inhalation airflow travels through a diverter or hole in manifold 114 (described in more detail in FIGS. 4-8). The portion of the inhalation airflow through open pocket 164B entrains a dose of powdered medicament 168B into the airflow, and the portion of the inhalation airflow through a diverter within manifold 114 intersects with the entrained airflow portion, grinding up the powdered medicament therein before exiting manifold 114.

[0058]

[0123] 4-8, manifold 114 will be described in more detail. Manifold 114 is configured to simultaneously deliver powdered medicaments 168A, 168B from respective open blister pockets 164A, 164B of each of first blister strip 160A and second blister strip 160B, respectively. Manifold 114 includes a body 170 that defines a first space or atrium 172A, a second space or atrium 172B, and a stack 180. As described in more detail herein, the separate and distinct compartments or spaces of first atrium 172A, second atrium 172B, and stack 180 divide, split, or otherwise separate the inhalation airflow drawn into manifold 114 by a user into multiple airflow paths through body 170 of manifold 114. More specifically, when an inhalation force is applied through the central opening 112 of the mouthpiece 110, the inhalation airflow is drawn through the inlet vent 106 of the inhalation device 100 into the first atrium 172A and the second atrium 172B of the manifold 114. The first atrium 172A and the second atrium 172B are disposed adjacent to or in juxtaposed relationship with the inlet vent 106. Upon entering the manifold 114, the inhalation airflow divides or splits into four airflow paths as it travels through the main body 170 of the manifold: a first diverted airflow path 192, a second diverted airflow path 194, a first intake airflow path 196, and a second intake airflow path 198. In other words, each of the first diverted air flow path 192, the second diverted air flow path 194, the first intake air flow path 196, and the second intake air flow path 198 is a respective air flow portion of the intake air flow that is drawn into the manifold 114.

[0059]

[0124] In this embodiment, the first atrium 172A and the second atrium 172B are disposed laterally adjacent to or alongside one another on one side of the main body 170 of the manifold 114. The first atrium 172A and the second atrium 172B are separated from one another by a partition wall 173 such that the first atrium 172A is not in fluid communication with the second atrium 172B. The first atrium 172A includes a single atrium inlet 174A, and the second atrium 172B includes a single atrium inlet 174B. The atrium inlets 174A, 174B are separate from one another and can also be considered inlets to the manifold 114. Thus, the manifold 114 includes two inlets: the atrium inlet 174A leading to or into the first atrium 172A, and the atrium inlet 174B leading to or into the second atrium 172B.

[0060]

[0125] The first atrium 172A includes a first atrium outlet 176A and a second atrium outlet 178A, and the second atrium 172B includes a first atrium outlet 176B and a second atrium outlet 178B. As described in more detail herein, the first atrium outlets 176A, 176B of each of the first atrium 172A and the second atrium 172B, respectively, direct or guide flow directly into the stack 180, and the second atrium outlets 178A, 178B of each of the first atrium 172A and the second atrium 172B, respectively, direct or guide flow into the open pockets 164A, 164B of the first blister strip 160A and the second blister strip 160B, respectively. In one embodiment, the profile or shape of the first atrium outlets 176A, 176B is substantially rectangular or oblong. However, the profile or shape of the first atrium outlets 176A, 176B is not limited to the shapes depicted herein and may alternatively be circular, triangular, or any other shape deemed suitable for the purposes described herein. Similarly, the profile or shape of the second atrium outlets 178A, 178B is substantially circular and includes a grille or crosspiece 197 (see FIG. 4) extending thereover to promote increased turbulence in the airflow. However, the profile or shape of the second atrium outlets 178A, 178B is not limited to the shapes depicted herein and may alternatively be rectangular, oblong, oval, triangular, or any other shape deemed suitable for the purposes described herein, with or without a grille extending thereover.

[0061]

[0126] 7, stack 180 is in fluid communication with each of first atrium 172A, second atrium 172B, open pocket 164A of first blister strip 160A, and second open pocket 164B of second blister strip 160B. Stack 180 has four inlets: first stack inlet 182, second stack inlet 184, third stack inlet 186, and fourth stack inlet 188. First stack inlet 182 is positioned with first atrium outlet 176A of first atrium 172A such that stack 180 and first atrium 172A are in fluid communication with each other. The second stack inlet 184 is aligned with the open pocket 164A of the first blister strip 160A such that the second stack inlet 184 is further in fluid communication with the second atrium outlet 178A of the first atrium 172A via the open pocket 164A. The third stack inlet 186 is in fluid communication with the second atrium outlet 176B of the second atrium 172B such that the stack 180 and the second atrium 172B are in fluid communication with each other. The fourth stack inlet 188 is in fluid communication with the open pocket 164B of the second blister strip 160B such that the fourth stack inlet 188 is further in fluid communication with the second atrium outlet 178B of the second atrium 172B via the open pocket 164B.

[0062]

[0127] The profile or shape of each of the first stack inlet 182 and the third stack inlet 186 is substantially rectangular or oblong. However, the profile or shape of the first stack inlet 182 and the third stack inlet 186 is not limited to the shape depicted herein and may alternatively be circular, triangular, or any other shape deemed suitable for the purposes described herein. Similarly, the profile or shape of the second stack inlet 184 and the fourth stack inlet 188 is substantially circular and includes a grille or crosspiece 195 (see FIG. 4 ) extending thereover to promote increased turbulence in the airflow. However, the profile or shape of the second stack inlet 184 and the fourth stack inlet 188 is not limited to the shape depicted herein and may alternatively be rectangular, oblong, oval, triangular, or any other shape deemed suitable for the purposes described herein, with or without a grille extending thereover.

[0063]

[0128] The stack 180 is a single stack having a single stack outlet 190. Thus, in this embodiment, the stack 180 has only one stack outlet 190. The stack outlet 190 can also be considered an outlet of the manifold 114. Thus, the manifold 114 includes only one outlet. The shape or profile of the stack outlet 190 is elliptical. However, the profile or shape of the stack outlet 190 is not limited to the shapes depicted herein and may alternatively be circular, rectangular, oblong, triangular, or any other shape deemed suitable for the purposes described herein. When the manifold 114 is assembled to the inhalation device 100, the stack outlet 190 is positioned and in fluid communication with the central opening 112 of the mouthpiece 110.

[0064]

[0129] The second atrium outlet 178A of the first atrium 172A is in fluid communication with the second stack inlet 184 to define a first intake airflow path 196 associated with the open blister pocket 164A of the first blister strip 160A. As the air stream flows through the open blister pocket 164A, it picks up the powdered medicament 168A disposed within the open blister pocket 164A. Thus, by passing through the open blister pocket 164A, the powdered medicament 168A is drawn into and transported by the air stream into the stack 180. After intake, the air stream contains the powdered medicament 168A.

[0065]

[0130] Similarly, the second atrium outlet 178B of the second atrium 172B is in fluid communication with the fourth stack inlet 188 to define a second intake airflow path 198 associated with the open blister pocket 164B of the second blister strip 160B. As the air stream flows through the open blister pocket 164B, it picks up the powdered medicament 168B disposed therein. Thus, by passing through the open blister pocket 164B, the powdered medicament 168B is drawn into and transported by the air stream into the stack 180. After intake, the air stream contains the powdered medicament 168B.

[0066]

[0131] The first atrium outlet 176A of the first atrium 172A is in fluid communication with the first stack inlet 182 to define a first diverted airflow path 192 of the manifold 114. Similarly, the first atrium outlet 176B of the second atrium 172B is in fluid communication with the third stack inlet 186 to define a second diverted airflow path 194 of the manifold 114. Each of the diverted airflow paths 192, 194 provides a lower resistance path for air flowing from outside the inhalation device 100 to the patient's mouth compared to the first and second intake airflow paths 196, 198. As a result, the overall airflow resistance of the inhalation device 100 is reduced, thereby enabling a higher overall flow rate to be achieved for the same inhalation pressure. Additionally, the diverted airflow paths 192, 194 provide for deagglomeration of the powdered medicaments 168A, 168B before they exit the manifold 114. Each of the first and second diverted airflow paths 192, 194 is configured to disrupt each of the first and second intake airflow paths 196, 198, thereby breaking down the medicament carried therethrough. More specifically, the first diverted airflow path 192 is directed into the path of the first intake airflow path 196 at a different angle from the first diverted airflow path 192. A region of higher shear is formed at the intersection between the first diverted airflow path 192 and the first intake airflow path 196, improving deagglomeration of the powdered medicament 168A before it exits the manifold 114. Similarly, the second diverted airflow path 194 is directed into the path of the second intake airflow path 198 at a different angle from the second diverted airflow path 194. A region of higher shear is formed at the intersection between the second diverted air flow path 194 and the second intake air flow path 198, improving deagglomeration of the powdered medicament 168B before it exits the manifold 114. The first diverted air flow path 192, the second diverted air flow path 194, the first intake air flow path 196, and the second intake air flow path 198 combine or mix within the stack 180 before exiting the manifold 114.

[0067]

[0132] 8, the inhalation air stream drawn in from outside the inhalation device 100 is split between two inlets of the manifold 114, namely, the first atrium inlet 174A and the second atrium inlet 174B. Thus, the inhalation air stream drawn in from outside the inhalation device simultaneously enters each of the first atrium 172A and the second atrium 172B. A first portion of the inhalation air stream entering the first atrium 172A flows into the open blister pocket 164A, and a second portion of the inhalation air stream entering the first atrium 172A flows directly into the stack 180. The first portion of the inhalation air stream in the open blister pocket 164A picks up or entrains the powdered medicament 168A disposed in the open blister pocket 164A and then continues into the stack 180. Within the stack 180, the second portion of the inhalation air stream from the first atrium 172A breaks up or deagglomerates the powdered medicament 168A entrained within the first portion of the inhalation air stream. Similarly, simultaneously, the first portion of the inhalation air stream entering the second atrium 172B flows into the open blister pocket 164B, and the second portion of the inhalation air stream entering the second atrium 172B flows into the stack 180. The first portion of the inhalation air stream within the open blister pocket 164B picks up or entrains the powdered medicament 168B disposed within the open blister pocket 164B and then continues into the stack 180. Within the stack 180, the second portion of the inhalation air stream from the second atrium 170B breaks up or deagglomerates the powdered medicament 168B entrained within the first portion of the inhalation air stream. Within stack 180, all portions of the air stream mix together before exiting manifold 114 toward the patient's mouth, and the combined air stream contains both medicament 168A from first blister strip 160A and medicament 168B from second blister strip 160B. Air flow through first atrium 172A and open blister pocket 164A is simultaneous with air flow through second atrium 172B and open blister pocket 164B.

[0068]

[0133] Due to the fact that the first atrium 172A and the second atrium 172B are separate and distinct compartments with the partition wall 173 extending between them, the inhalation air stream entering the manifold 114 is directed towards the outlet of each atrium. By directing the separated inhalation air streams into the open blister pockets 164A, 164B in this manner, the turbulent energy of the airflow is reduced at this stage, and therefore the overall airflow resistance of the inhalation device 100 is reduced. The overall airflow resistance allows the patient to achieve a higher flow rate at the same inhalation pressure, which can improve the effectiveness of drug delivery.

[0069]

[0134] 9A and 9B, the dispensing subassembly 120 of the inhalation device 100 will be described in more detail. The dispensing subassembly 120 is configured to advance each blister strip 160A, 160B and open its pockets 164A, 164B each time the mouthpiece cover 108 is fully opened by the user. The first blister strip 160A and the second blister strip 160B are disposed within a first compartment 118A and a second compartment 118B within the housing 102. More specifically, the compartments 118A, 118B are formed via an internal chassis 116 disposed within the housing 102. Via the dispensing subassembly 120, the consecutive pockets 164A, 164B of each blister strip 160A, 160B are guided toward a manifold 114 disposed along or approximately along the centerline of the inhalation device 100. When placed in manifold 114, pockets 164A, 164B of each blister strip 160A, 160B are open, and powdered medicament 168A, 168B in the open pockets of each blister strip 160A, 160B are available for inhalation. As described herein, the empty bottom sheets 162A, 162B and top sheets 166A, 166B of blister strips 160A, 160B are rolled up by dispensing subassembly 120. FIG. 9A is a front view of inhalation device 100 with mouthpiece cover 108 in the open position, with the front half or portion of housing 102 of inhalation device 100 removed for illustrative purposes only. FIG. 9B is a rear view of inhalation device 100 with mouthpiece cover 108 and housing 102 removed for illustrative purposes only.

[0070]

[0135] The dispensing subassembly 120 includes a central driver gear 122, a ratchet mechanism 124, a first idler or intermediate gear 126, a second idler or intermediate gear 127, a first bottom sheet take-up gear 128A and a second bottom sheet take-up gear 128B, a first indexing gear 130A and a second indexing gear 130B, and a first top sheet take-up gear 150A and a second top sheet take-up gear 150B. The first bottom sheet take-up gear 128A, the first indexing gear 130A, and the first top sheet take-up gear 150A are associated with the advancement of the first blister strip 160A, and the second bottom sheet take-up gear 128B, the second indexing gear 130B, and the second top sheet take-up gear 150B are associated with the advancement of the second blister strip 160B.

[0071]

[0136] As shown in FIG. 11 , first indexing gear 130A and second indexing gear 130B are attached to or integrally formed with first indexing spool 131A and second indexing spool 131B, respectively. First indexing spool 131A and second indexing spool 131B each include a pair of recesses 132A and 132B thereon, respectively. Each recess of the pair of recesses 132A and 132B is configured to receive a pocket 164A and 164B of blister strip 160A and 160B, respectively. Through rotation of first indexing gear 130A and second indexing gear 130B, first indexing spool 131A and second indexing spool 131B rotate and operate to move recesses 132A and 132B, respectively, adjacent to or juxtaposed with manifold 114. As blister strips 160A, 160B are advanced by indexing spools 131A, 131B, top sheets 166A, 166B of blister strips 160A, 160B are peeled away from bottom sheets 162A, 162B of the blister strips such that their pockets 164A, 164B adjacent manifold 114 are opened and the powdered medicament 168A, 168B therein are available for ingestion. More specifically, top sheets 166A, 166B are peeled away from bottom sheets 162A, 162B, respectively, such that pockets 164A, 164B of each bottom sheet 162A, 162B are opened or opened to expose respective doses of powdered medicament 168A, 168B. Opening or unrolling pockets 164A, 164B is accomplished by relative rotation between indexing spools 131A, 131B and upper sheet take-up gears 150A, 150B. Indexing spools 131A, 131B essentially grip bottom sheets 162A, 162B, respectively, and upper sheet take-up gears 150A, 150B essentially grip top sheets 166A, 166B, respectively. As indexing spools 131A, 131B and upper sheet take-up gears 150A, 150B rotate relative to one another, bottom sheets 162A, 162B and top sheets 166A, 166B are peeled away from one another.As described in more detail herein, indexing spools 131A, 131B and top sheet take-up gears 150A, 150B are driven to rotate in opposite directions via gearing such that each top sheet 166A, 166B is peeled from its respective bottom sheet 162A, 162B as the gears are driven. Thus, dispensing subassembly 120 opens and places each leading pocket 164A, 164B in fluid communication with manifold 114, thereby making the powdered medicament 168A, 168B in the opened pocket 164A, 164B available for inhalation.

[0072]

[0137] The first and second bottom sheet take-up gears 128A and 128B operate to take up the empty bottom sheets 162A and 162B of the blister strips 160A and 160B, respectively. As shown in FIG. 11 , the first and second bottom sheet take-up gears 128A and 128B are attached to or integrally formed with spindles 129A and 129B, respectively. Through rotation of the first and second bottom sheet take-up gears 128A and 128B, the first and second spindles 129A and 129B rotate and operate to take up the bottom sheets 162A and 162B as the inhalation device 100 operates. The ends of each bottom sheet 162A, 162B are fixed to the first bottom sheet winding gear 128A and the second bottom sheet winding gear 128A so that progressive rotation of the first bottom sheet winding gear 128A and the second bottom sheet winding gear 128B causes the bottom sheets 162A, 162B to be wound around them into tight coils.

[0073]

[0138] The first upper sheet take-up gear 150A and the second upper sheet take-up gear 150B operate to wind the upper sheets 166A and 166B of the blister strips 160A and 160B, respectively. As described in more detail herein with respect to Figures 14A-14E, the first upper sheet take-up gear 150A and the second upper sheet take-up gear 150B are coupled to wind-up hubs 152A and 152B, respectively. Through rotation of the first upper sheet take-up gear 150A and the second upper sheet take-up gear 150B, the first wind-up hub 152A and the second wind-up hub 152B rotate and operate to wind or wind the upper sheets 166A and 166B as the inhalation device 100 operates. The ends of each upper sheet 166A, 166B are fixed to the first and second winding hubs 152A, 152B so that the progressive rotation of the first and second upper sheet winding gears 150A, 150B causes the upper sheets 166A, 166B to be wound therearound into tight coils.

[0074]

[0139] The central driver gear 122 of the dispensing subassembly 120 is attached to the mouthpiece cover 108 via a ratchet mechanism 124. The ratchet mechanism 124 is shown removed from the inhalation device 100 in FIG. 10 . The ratchet mechanism 124 includes a ratchet 125 attached to the mouthpiece cover 108 and a ratchet gear 123 formed with or attached to the central driver gear 122. When the mouthpiece cover 108 is opened, the ratchet 125 is driven in a second, opposite direction by the mouthpiece cover 108. The ratchet 125 then drives the ratchet gear 123 in the second, opposite direction to advance or actuate the dispensing subassembly 120. When the mouthpiece cover 108 is returned to its closed position, the dispensing subassembly 120 does not advance or actuate and remains stationary. Therefore, the opening movement of the mouthpiece cover 108 is transmitted to the central driver gear 122 , but the closing movement of the mouthpiece cover 108 is not transmitted to the central driver gear 122 .

[0075]

[0140] More specifically, ratchet gear 123 includes a plurality of circumferentially spaced inner stop surfaces 123A and outer stop surfaces 123B around its outer periphery or edge. Ratchet 125 includes a plurality of flexible ratchet arms 125A configured to interact with the circumferentially spaced inner stop surfaces 123A of ratchet gear 123. Ratchet 125 rotates in a first direction with mouthpiece cover 108 as mouthpiece cover 108 moves from a closed first position to an open second position. When rotating in the first direction, ratchet arms 125A engage and drive the circumferentially spaced inner stop surfaces 123A of ratchet gear 123, as shown in FIG. 10B, so that torque is transmitted to central driver gear 122. Ratchet gear 123 is attached to or formed with central driver gear 122 so that central driver gear 122 rotates in a first direction simultaneously with mouthpiece cover 108. As described above, movement of mouthpiece cover 108 to the second position results in the opening and placement of pockets 164A, 164B of each blister strip 160A, 160B for subsequent simultaneous inhalation of powdered medicament 168A, 168B by the patient.

[0076]

[0141] However, when the mouthpiece cover 108 is returned to its closed first position, the ratchet arms 125A do not interact with the inner stop surfaces 123A of the ratchet gear 123, and therefore, reverse rotation of the ratchet 125 is not transmitted to the central driver gear 122. More specifically, when the ratchet 125 is rotated in a second, opposite direction (i.e., counterclockwise), the ratchet arms 125A flex radially inward, and no significant torque is transmitted to the ratchet gear 123 and the central driver gear 122. Although frictional drag between the ratchet 125 and the ratchet gear 123 may tend to temporarily pull the ratchet gear 123 in the second, opposite direction (i.e., counterclockwise), reverse winding is prevented by interaction between one of the outer stop surfaces 123B of the ratchet gear 123 and the detent arm 121 in the retainer plate of the inhalation device 100, as shown in FIG. 10A .

[0077]

[0142] In one embodiment, a detent (not shown) can be disposed between the inner surface of the mouthpiece cover 108 and the outer surface of the housing 102. The detent can be a mating protrusion and groove configured to temporarily resist or prevent movement of the mouthpiece cover 108 relative to the housing 102 until a user applies a force to the mouthpiece cover 108 (i.e., when opening the mouthpiece cover 108) and releases the detent by moving one of the mating features of the detent out of or past the other of the mating features of the detent. For example, a protrusion, bump, or other raised structure can be formed on the outer surface of the housing 102, and a mating groove, dimple, or other recessed structure can be formed on the inner surface of the mouthpiece cover 108. Alternatively, a protrusion, bump, or other raised structure can be formed on the inner surface of the mouthpiece cover 108, and a mating groove, dimple, or other recessed structure can be formed on the outer surface of the housing 102. The groove is configured to receive the recess when the mouthpiece cover 108 is in the closed position of FIG. 1A. When a user applies sufficient force to overcome the friction between the mating projections and grooves, the mouthpiece cover 108 begins to open, moving away from the closed position of Figure 1A. The detents are configured to prevent or inhibit unintentional opening of the mouthpiece cover 108. Additionally, the detents are configured to account for rotational clearances or tolerances within the ratchet mechanism 124 so that the dispensing and counter mechanisms within the inhalation device 100 are actuated upon initial or initial movement of the mouthpiece cover 108 from the closed position toward the open position.

[0078]

[0143] 11 , central driver gear 122 directly or indirectly drives the remaining gears of dispensing subassembly 120. This gear train configuration provides incremental indexing or advancement of blister strips 160A, 160B via first indexing gear 130A and second indexing gear 130B, and also provides winding (via top sheet take-up gears 150A, 150B and bottom sheet take-up gears 128A, 128B, respectively) of the top and bottom sheets of blister strips 160A, 160B due to rotational movement of mouthpiece cover 108 in a first direction from its closed, first position to its open, second position. As central driver gear 122 rotates with mouthpiece cover 108 in a first direction, central driver gear 122 engages or directly drives second indexing gear 130B to rotate it in a second, opposite direction. Therefore, the second spool 131B, and the second blister strip 160B advanced thereby, also rotate in the second, opposite direction. As the second indexing gear 130B rotates in the second, opposite direction, the second indexing gear 130B engages with or directly drives the first indexing gear 130A, causing it to rotate in the first direction. Therefore, the first indexing spool 131A, and the first blister strip 160A advanced thereby, also rotate in the first direction.

[0079]

[0144] In one embodiment, the first direction is clockwise and the second, opposite direction is counterclockwise. In the depicted embodiment, when mouthpiece cover 108 is opened, central driver gear 122 rotates in a clockwise direction. Thus, second indexing gear 130B (together with second spool 131B and second blister strip 160B) rotates in a counterclockwise direction, and first indexing gear 130A (together with first indexing spool 131A and first blister strip 160A) rotates in a clockwise direction. However, as will be understood by those skilled in the art, the first direction can alternatively be counterclockwise and the second, opposite direction can be clockwise, as long as the gear train formed by dispensing subassembly 120 moves or advances first blister strip 160A in the opposite direction to second blister strip 160B. Additionally, as will be understood by those skilled in the art, the gear train formed by dispensing subassembly 120 may include one or more idler gears (not shown) that change the order of rotation between central driver gear 122, second indexing gear 130B, and first indexing gear 130A. The presence of such idler gears does not affect the overall function of the gear train, as long as the gear train moves or advances first blister strip 160A in the opposite direction to second blister strip 160B. For example, an idler gear (not shown) may be disposed between central driver gear 122 and first indexing gear 130A, such that central driver gear 122 (rotating in a first direction) directly drives the idler gear to rotate in a second, opposite direction. The idler gear may be arranged to directly drive a first indexing gear 130A in a first direction, and the first indexing gear 130A directly drives a second indexing gear 130B in a second, opposite direction.

[0080]

[0145] To maintain tension applied to blister strips 160A, 160B, first bottom sheet take-up gear 128A and second bottom sheet take-up gear 128B rotate simultaneously in the same direction with first indexing gear 130A and second indexing gear 130B, respectively, and first top sheet take-up gear 150A and second top sheet take-up gear 150B rotate simultaneously in the opposite direction with first indexing gear 130A and second indexing gear 130B, respectively. As central driver gear 122 rotates in a first direction, central driver gear 122 engages with or directly drives first idler gear 126 to rotate it in a second, opposite direction, and first idler gear 126 engages with or directly drives first bottom sheet take-up gear 128A to rotate it in the first direction. Thus, first spindle 129A, and thus bottom sheet 162A wound thereby, also rotates in a first direction to wind or take up empty bottom sheet 162A of first blister strip 160A as first blister strip 160A is advanced by dispensing subassembly 120. In addition, first top sheet take-up gear 150A interacts with or is driven by first indexing gear 130A. As first indexing gear 130A rotates in the first direction, first top sheet take-up gear 150A is driven to rotate in a second, opposite direction to wind up top sheet 166A of first blister strip 160A.

[0081]

[0146] As central driver gear 122 rotates in a first direction, first idler gear 126 is driven to rotate in a second, opposite direction as described above, and first idler gear 126 mates with or directly drives second idler gear 127, causing it to rotate in the first direction. Second idler gear 127 mates with or directly drives second bottom sheet take-up gear 128B, causing it to rotate in the second direction. Thus, second spindle 129B, and the bottom sheet 162B wound thereby, also rotates in the second direction, causing or taking up the empty bottom sheet 162B of second blister strip 160B as second blister strip 160B is advanced by dispensing subassembly 120. Additionally, the second upper sheet take-up gear 150B interacts with or is driven by the second indexing gear 130B. As the second indexing gear 130B rotates in the second opposite direction, the second upper sheet take-up gear 150B is driven to rotate in the first direction to wind up the upper sheet 166B of the second blister strip 160B.

[0082]

[0147] 12A-12D, counter subassembly 134 will be described in more detail. Dispensing subassembly 120 preferably directly drives counter subassembly 134, such that the dose counter is automatically incremented simultaneously with a medication dose being indexed or delivered by inhalation device 100. Thus, beyond manipulating mouthpiece cover 108 to activate dispensing subassembly 120, the user does not need to perform any additional operational steps to update the dose counter. Because the dose counter is automatically incremented when mouthpiece cover 108 is opened, it is intuitive to the user what the dose counter pertains to.

[0083]

[0148] Counter subassembly 134 includes a first count wheel or units ring 140 and a second counting component or tens mechanism 136. First count wheel 140 is driven from dispensing subassembly 120 of inhalation device 100 to rotate a fixed angle per dose, in this embodiment, displaying the second digit of a two-digit number of available dose counts. Second count component 136 is intermittently driven from first count wheel 140 to rotate a fixed angle per revolution of first count wheel 140, as described in more detail below. In this embodiment, second count component 136 displays the first digit of a two-digit number of available dose counts. In this manner, first count wheel 140 and second counting component 136 collectively display the number of doses remaining in inhalation device 100, as shown in FIGS. 12A and 12B. While the counter subassembly embodiment described herein displays a two-digit number, those skilled in the art will appreciate that if the total number of doses in the inhalation device exceeds 100, the count indicia may be modified to display a three-digit number.

[0084]

[0149] The front or indicia-bearing face or surface 141 of the first count wheel 140 includes count indicia disposed thereon, including units' or "ones'" digits. More specifically, as shown in Figures 12A and 12B, the count indicia of the first count wheel 140 include the numbers 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9 in a circular pattern near the outer periphery of the indicia-bearing face 141. The angle between each digit is the same as the rotation angle of the first count wheel 140 per dose. The indicia-bearing face 141 is planar.

[0085]

[0150] The front or indicia-bearing face or surface 137 of the second count component 136 includes count indicia disposed thereon, including "tens" digits. The count indicia of the second count component 136 include the digits 3, 2, and 1, and may also include a single flag SF and a double flag DF near the outer periphery of the indicia-bearing face 137. The angle between each count indicia or digit is the angle of rotation of the second count component 136 per rotation of the first count wheel 140. The indicia-bearing face 137 is planar.

[0086]

[0151] The display window 104 in the housing 102 is positioned such that one number on the first count wheel 140 and one number on the second count component 136 are visible within the display window and adjacent to each other to form a two-digit number. The displayed number on the second count component 136 reflects or tracks the number of "tens" of doses remaining in the inhalation device 100, while the displayed number on the first count wheel 140 reflects or tracks the number of "units" of doses remaining. When there are fewer than ten doses remaining, the second count component 136 displays a single flag SF in the display window 104 instead of or in place of a zero. In one embodiment, for example, the single flag SF may be a colored block with no numbers on it to indicate to the user that they are nearing the end of the available doses in the inhalation device 100. When the number of doses remaining reaches zero, the second count component 136 displays a double flag DF in the display window 104 instead of a number. In one embodiment, for example, the double flag DF may be a colored block with no numbers thereon that covers the numbers on the first count wheel 140 to provide clear visual feedback to the user that no doses remain in the inhalation device 100. The double flag DF is configured to cover the numbers on the first count wheel 140 when no doses remain in the inhalation device 100.

[0087]

[0152] 12A-12D, the units or "units" digits are circumferentially arranged in descending order in a first direction on the first count wheel 140, and the "tens" digits are arranged in descending order in a second, opposite direction about the circumference of the second counting component 136. While the counter subassembly described herein indicates the number of doses remaining in the inhalation device 100, those skilled in the art will appreciate that the counter subassembly may be modified to indicate the number of doses delivered by the inhalation device by reversing the order of the count indicia arranged on the counting subassembly.

[0088]

[0153] 12C and 12D, the structure and operation of the first count wheel 140 and second counting component 136 will now be described in more detail. FIG. 12C is a cross-sectional view taken along line CC in FIG. 12B, which is along a midpoint between the indicia display face and the opposite rear face of the counting subassembly. FIG. 12D is a cross-sectional view taken along line DD in FIG. 12C, adjacent the opposite rear face of the counting subassembly. The relative terms "front" and "rear" are used herein for illustrative purposes only and relate to how the inhaler device is typically positioned by a user during use, with the front face of the inhaler device containing the display window for the counter mechanism.

[0089]

[0154] The first count wheel 140 is an annular or ring-shaped component having a front or indicia-bearing surface 141 and an opposite back surface containing a counter gear 148, as best seen in the cross-sectional view of FIG. 12D. The counter gear 148 may be integrally formed on or attached to the first count wheel 140. An outer circumferential surface or portion 143 extends between the front and back surfaces of the first count wheel 140. The outer circumferential side portion 143 may be stepped, having a smaller diameter along the back surface of the first count wheel 140 and a larger diameter along the front surface of the first count wheel 140. The stepped nature of the outer circumferential side portion 143 is evident by comparing their relative diameters in FIGS. 12C and 12D. Stated differently, the indicia-bearing surface 141 of the first count wheel 140 has a larger outer diameter than the counter gear 148.

[0090]

[0155] Adjacent to the counter gear 148, the first count wheel 140 includes a single tooth or protrusion 142 extending radially outward from an outer peripheral side 143. Along the front or indicia bearing face 141 of the first count wheel 140, the outer peripheral side 143 is generally circular with a clearance notch or recess 145 formed around the single tooth 142. The function of the clearance recess 145 is described in more detail below.

[0091]

[0156] The second count component 136 is configured to rotate about a pivot point 147. The second count component 136 is a non-annular or partial disc component having a front or indicia-bearing surface 137 and an opposite back surface including a plurality of notches 138, as shown in the cross-sectional views of FIGS. 12C and 12D. An outer surface or outer portion 139 extends between the front and back surfaces of the second count component 136. The outer surface 139 may be stepped, having a smaller radial dimension along the back surface of the second count component 136 and a larger radial dimension along the front surface of the second count component. The stepped nature of the outer portion 139 is apparent by comparing their relative diameters in FIGS. 12B and 12C.

[0092]

[0157] A plurality of notches 138 are formed in an outer portion 139 of the second counting component 136 and do not penetrate the front or indicia-bearing surface 137. In one embodiment, the second counting component 136 includes four notches 138, although the number of notches is exemplary and depends on the capacity or total number of doses available within the inhalation device 100. Each notch 138 extends radially inward toward a pivot point 147 of the second counting component 136 and is configured to mate with or receive a single tooth 142 of the first counting wheel 140. The outer portion 139 of the second counting component 136 may be considered to include a plurality of segments 135, with each segment 135 extending between two adjacent or neighboring notches 138. Along each segment 135 , the outer side 139 of the second counting element 136 is concave, forming an inverted curved or arcuate depression 133 that matches the outer periphery 143 of the first counting wheel 140 .

[0093]

[0158] The first count wheel 140 is driven by the second bottom sheet take-up gear 128B of the dispensing subassembly 120 so that the first count wheel 140 rotates a fixed angle each time a dose is dispensed. More specifically, a transfer gear 144 is attached to the opposite end of the second spindle 129B of the second bottom sheet take-up gear 128B, such that the transfer gear 144, the second spindle 129B, and the second bottom sheet take-up gear 128B rotate simultaneously as an assembly. This causes the transfer gear 144 to rotate in a second, opposite direction together with the second bottom sheet take-up gear 128B when the mouthpiece cover 108 is opened. The transmission gear 144 mates with or directly drives the idler gear 146 to rotate it in a first direction, and the idler gear 146 mates with or directly drives the counter gear 148 to rotate it in a second, opposite direction. Thus, the counter gear 148 rotates in the same direction as the transmission gear 144. As will be apparent to those skilled in the art, rotation of the transmission gear 144 and the counter gear 148 in the same direction may also be achieved via a gear train in which the transmission gear 144 directly drives the counter gear 148 in the same direction. For example, as depicted in FIGS. 12B-12D , the desired rotation scheme is achieved when the counter gear 148 is an internal gear and the transmission gear 144 is a spur or planetary gear, whereby the transmission gear 144 mates with or directly drives the internal counter gear 148 in the same direction. The first count wheel 140 is attached to the counter gear 148 and rotates together as an assembly so that when the mouthpiece cover 108 is opened, the first count wheel 140 rotates in a second, opposite direction. Accordingly, various suitable gear trains may be utilized herein so that the transfer gear 144 and the counter gear 148 rotate in the same direction.

[0094]

[0159] 12C , the second count component 136 is positioned adjacent or next to an outer peripheral side 143 of the first count wheel 140 such that a single tooth 142 of the first count wheel 140 engages with a notch 138 of the plurality of notches 138 of the second count component 136 once per rotation of the first count wheel 140, causing the second count component 136 to intermittently rotate. Stated another way, with each complete rotation of the first count wheel 140, the single tooth 142 engages with a notch 138 of the second count component 136, turning or rotating the second count component 136 a fixed amount. Thus, there is a fixed rotation of the second count component 136 once per rotation of the first count wheel 140. The first count wheel 140 directly drives the second count component 136, so that the second count component 136 rotates in the opposite direction to the first count wheel 140. In the embodiment of Figures 12A-12D, the second count component 136 is configured to rotate in a first direction and the first count wheel 140 is configured to rotate in a second, opposite direction. The second count component 136 is stationary and does not rotate when the single tooth 142 of the first count wheel 140 is not engaged with the notch 138 of the second count component 136.

[0095]

[0160] The second counting component 136 is disposed adjacent to or alongside the first counting wheel 140 in a common plane, and therefore the second counting component 136 rotates on a different axis of rotation than the first counting wheel 140. In other words, the first counting wheel 140 rotates about a first axis, and the second counting component 136 rotates about a second axis, which is parallel to and spaced apart from the first axis.

[0096]

[0161] As mentioned above, along each segment 135, the outer side 139 of the second count component 136 is concave, forming an arcuate recess 133 that mates with the outer periphery 143 of the first count wheel 140. As best shown in FIG. 12C , the geometry of the arcuate recess 133 matches the circular profile of the first count wheel 140 to prevent the second count component 136 from unintentionally rotating when not engaged with the first count wheel 140. In particular, this geometry or profile of the outer side 139 of the second count component 136 ensures that the second count component 136 does not rotate and remains stationary when a single tooth 142 of the first count wheel 140 is not engaged with one of the notches 138 of the second count component 136. Conversely, when a single tooth 142 of the first count wheel 140 engages or is received within one of the notches 138 of the second count component 136, the clearance recess 145 of the first count wheel 140 allows the second count component 136 to briefly rotate with the first count wheel 140 to change the tens digit display.

[0097]

[0162] 13A, 13B, and 14A-14E, first tensioning mechanism 151A and second tensioning mechanism 151B are described in more detail. Tensioning mechanisms 151A and 151B function to peel top sheets 166A and 166B, respectively, from first blister strip 160A and second blister strip 160B to maintain a consistent peel distance or volume over the life of the device. More specifically, tensioning mechanisms 151A and 151B ensure that the peel distance of top sheets 166A and 166B is configured to adequately open pockets 164A and 164B for each dose to achieve effective dispensing of powdered medicament 168A and 168B to the user. If the peel distance or volume is too low, the pockets may not be fully exposed, making it more difficult to achieve sufficient expulsion of the powdered medicament disposed therein upon inhalation. Furthermore, if the peel distance or amount is too high, the next or subsequent pocket may be prematurely exposed, risking the loss of some of the medication disposed therein and resulting in an underdose at the next dispense. The tensioning mechanisms 151A, 151B also function to maintain the sheet tension of the top sheets 166A, 166B over the life of the device. The top sheets 166A, 166B must be under consistent tension to ensure proper operation of the inhalation device 100. The tension of each top sheet 166A, 166B is related to the force required by the user to operate the inhalation device 100 and move the mouthpiece cover 108. Therefore, ensuring consistent tension in the top sheets 166A, 166B provides a more consistent user experience over the life of the device. Maintaining consistent tension in the top sheets 166A, 166B also results in more consistent and lower peak mechanical stresses in the top sheets 166A, 166B and surrounding components, which reduces the risk of mechanical failure during use.

[0098]

[0163] The first tensioning mechanism 151A is associated with the first upper sheet take-up gear 150A for winding the upper sheet 166A of the first blister strip 160A, and the second tensioning mechanism 151B is associated with the second upper sheet take-up gear 150B (see FIGS. 9A and 9B) for winding the upper sheet 166B of the second blister strip 160B. Because the second tensioning mechanism 151B operates in the same manner, only the first tensioning mechanism 151A will be described herein for brevity. It will be apparent to those skilled in the art that certain features or components of the second tensioning mechanism 151B (i.e., cam surfaces described herein) may be modified to extend in the opposite direction from that described below such that the second tensioning mechanism 151B is configured to operate in the opposite direction to the first tensioning mechanism 151A. Preferably, the first tensioning mechanism 151A and the second tensioning mechanism 151B use several components of the same design (i.e., the compression spring and winding hub described herein), which can reduce manufacturing and assembly costs compared to other inhalation devices where all components must be manufactured separately for each side of the device in order to operate in opposite directions.

[0099]

[0164] The tensioning mechanism 151A includes a first upper sheet take-up gear 150A, a take-up hub 152A having a hook 153A integrally formed therewith or secured thereto, a base 154A having a cam surface 155A integrally formed therewith or secured thereto, a nut 156A, a shaft 157A, and a compression spring 158A extending or disposed between the nut 156A and the upper end of the take-up hub 152A. The compression spring 158A biases the nut 156A downward toward the base 154A and into the cam surface 155A. The compression spring 158A is disposed around or around the shaft 157A and is longitudinally or axially adjacent to the nut 156A, and the take-up hub 152A is disposed around or around the nut 156A and compression spring 158A. Stated another way, the take-up hub 152A surrounds or encircles the nut 156A and compression spring 158A housed therein.

[0100]

[0165] The top sheet 166A of the first blister strip 160A is secured or attached to the take-up hub 152A via the hook 153A so that as the take-up hub 152A rotates, the top sheet 166A of the first blister strip 160A wraps around it. The hook 153A is configured to be attached to a leading end of the top sheet 166A so that rotation of the take-up hub 152A results in the top sheet 166A wrapping or wrapping around the take-up hub 152A. As the take-up hub 152A completes multiple rotations over the life of the inhalation device 100, the top sheet 166A of the first blister strip 160A wraps around itself multiple times, increasing its radial position on the take-up hub 152A; i.e., the radial distance of each subsequent wrap of the top sheet 166A from the take-up hub 152A increases with each wrap. Because the rotation of the base 154A corresponds to the rotation of the first top sheet take-up gear 150A, the base 154A rotates a fixed amount for each dose, and the distance that the top sheet 166A of the first blister strip 160A is peeled away from the bottom sheet 162A is determined by the tangential movement of the top sheet 166A of the first blister strip 160A on the take-up hub 152A. This tangential movement can be calculated as θ*r, where θ is the angle of rotation of the take-up hub 152A per dose, and r is the radial position of the top sheet 166A of the first blister strip 160A on the take-up hub 152A. Thus, as the radial position of the top sheet 166A of the first blister strip 160A increases, this tangential distance increases for a given rotation of the take-up hub 152A, and without changing the mechanism, the top sheet 166A of the first blister strip 160A will peel further away from the bottom sheet 162A later in the device's life. This is known as the wrap effect and is illustrated by a comparison of Figures 13A and 13B. Figure 13A is a schematic diagram of the first blister strip 160A early in the device's life, and Figure 13B is a schematic diagram of the first blister strip 160A later in the device's life. Figure 13B shows how the effective diameter of the take-up hub 152A increases as the first blister strip 160A wraps around the take-up hub 152A.

[0101]

[0166] To ensure that the top sheet 166A of the first blister strip 160A is peeled off the same amount for each dose and to compensate for winding effects, the tensioning mechanism 151A includes a cam surface 155A, a nut 156A, and a compression spring 158A. The function of the cam surface 155A, the nut 156A, and the compression spring 158A is to provide a constant driving tension to the top sheet 166A throughout the entire strip length. As described in more detail herein, increasing the tension along the top sheet 166A causes the take-up hub 152A to rotate relative to the base 154A, reducing the tension along the top sheet 166A. As the take-up hub 152A rotates relative to the base, the compression spring 158A is compressed, and the axial compressive force of the compression spring 158A is transferred to a torque applied to the take-up hub 152A.

[0102]

[0167] The structure of the tensioning mechanism 151A will be described in more detail with reference to Figures 14B to 14D. The base 154A is attached to or integrally formed with the first upper sheet take-up gear 150A, and rotates as an assembly when the first upper sheet take-up gear 150A is driven to rotate. For example, the base 154A may include a plurality of gear teeth integrally formed or fixed to its outer circumferential surface to form the first upper sheet take-up gear 150A. The shaft 157A extends from the base 154A and is attached to or integrally formed with the base 154A, and rotates together with the base 154A. As a result, when the first upper sheet take-up gear 150A is driven to rotate, the shaft 157A, the base 154A, and the first upper sheet take-up gear 150A rotate as an assembly.

[0103]

[0168] Nut 156A is disposed between take-up hub 152A and base 154A and is coupled to each of take-up hub 152A and base 154A. Nut 156A is disposed around shaft 157A and is coupled to base 154A via at least one inwardly extending rib 119A that protrudes or extends radially inward from the inner circumferential surface of nut 156A. In one embodiment, nut 156A includes multiple inwardly extending ribs 119A that act as cam followers. In one embodiment, the multiple inwardly extending ribs 119A are circumferentially spaced apart in equal increments. More specifically, as best shown in FIG. 14C , inwardly extending rib 119A of nut 156A is disposed on and engages cam surface 155A of base 154A. Additionally, nut 156A is coupled to take-up hub 152A via splined connection 159A such that take-up hub 152A rotates with nut 156A without permitting relative rotation therebetween. Stated another way, due to splined connection 159A, take-up hub 152A is rotationally locked to nut 156A such that nut 156A and take-up hub 152A rotate as an assembly. As best shown in FIG. 14C , splined connection 159A includes outwardly extending ribs 117A that protrude or extend radially outward from the outer periphery of nut 156A and are received within axial slots 115A in take-up hub 152A. The outwardly extending ribs 117A are permitted to slide or move axially along the axial slots 115A so that the nut 156A is permitted to slide or move axially relative to the take-up hub 152A, but the outwardly extending ribs 117A do not allow the nut 156A to rotate relative to the take-up hub 152A.

[0104]

[0169] When the base 154A rotates in the second opposite direction with the first upper sheet take-up gear 150A, the nut 156A and take-up hub 152A also rotate in the second opposite direction due to the interaction between the nut 156A, the compression spring 158A, and the cam surface 155A of the base 154A. More specifically, when the base 154A is rotationally driven in the second opposite direction, the take-up hub 152A rotates in the second opposite direction via engagement between the inwardly extending rib 119A of the nut 156A and the cam surface 155A. As shown in FIG. 14D , the cam surface 155A includes alternating sections of a vertical surface 111A and an angled or inclined surface 113A. The vertical surface 111A extends generally parallel to the longitudinal axis of the shaft 157A. When base 154A is rotationally driven in a second, opposite direction (i.e., counterclockwise in this embodiment), nut 156A and take-up hub 152A, which are rotationally locked thereto, rotate in the second, opposite direction with base 154A. The interaction between compression spring 158A, nut 156A, and cam surface 155A applies torque to nut 156A from cam surface 155A in a direction that pushes nut 156A down onto cam surface 155A. Compression spring 158A presses nut 156A against inclined surface 113A of cam surface 155A, resulting in a torque acting on take-up hub 152A that drives take-up hub 152A in the second, opposite direction. As a result of this interaction when base 154A moves counterclockwise, nut 156A and take-up hub 152A also rotate counterclockwise with base 154A. Those skilled in the art will appreciate that the pattern of cam surface 155A is exemplary. Threads or other angled surfaces can be utilized as cam surface 155A.

[0105]

[0170] Due to the interaction of nut 156A with compression spring 158A and cam surface 155A of base 154A, take-up hub 152A rotates with base 154A in a second, opposite direction, while allowing relative rotation between take-up hub 152A and base 154A. More specifically, when sufficient torque is applied between take-up hub 152A and base 154A, take-up hub 152A rotates relative to base 154A. Because take-up hub 152A is allowed to rotate relative to base 154A in a direction that reduces tension in top sheet 166A (i.e., in a first direction), this relative rotation stabilizes or balances the tension in top sheet 166A via deflection of compression spring 158A. Thus, tensioning mechanism 151A acts as a torsion or torque limiter between take-up hub 152A and base 154A to control the tension in top sheet 166A of first blister strip 160A.

[0106]

[0171] In addition to the torque applied to nut 156A from cam surface 155A, there is also an opposing torque acting on nut 156A from its interaction with take-up hub 152A via outwardly extending ribs 117A. This opposing torque results from tension in upper seat 166A acting to apply a torque to take-up hub 152A. The two opposing torques on nut 156A are balanced, and therefore compression spring 158A (via nut 156A and cam surface 155A) effectively counterbalances the tension in upper seat 166A. As the tension in upper seat 166A increases, nut 156A moves further up cam surface 155A, increasing the spring force of compression spring 158A to compensate for the increased tension.

[0107]

[0172] More specifically, due to the wrapping effect described above, as the take-up hub 152A rotates, the radial position of the top sheet 166A of the first blister strip 160A increases. As a result of this increased radial position, the take-up hub 152A attempts to peel a longer length of the top sheet 166A, and the tension on the top sheet 166A increases due to the change in the peel angle between the top sheet 166A of the first blister strip 160A and the bottom sheet 162A of the first blister strip 160A. As the tension on the top sheet 166A increases, the torque that the top sheet 166A applies to the take-up hub 152A also increases. Rather than continuing to increase in torque, the take-up hub 152A begins to rotate in a second direction relative to the base 154A, causing the nut 156A to spiral up the cam surface 155A of the base 154A, thereby compressing the compression spring 158A. More specifically, when take-up hub 152A and its rotationally locked nut 156A begin to rotate in a second direction due to increased tension on top seat 166A, base 154A and cam surface 155A remain stationary, while inwardly extending rib 119A of nut 156A moves along inclined surface 113A of cam surface 155A toward compression spring 158A, i.e., above cam surface 155A. Compression spring 158A compresses as nut 156A presses against it. As nut 156A moves relative to base 154A, outwardly extending rib 117A of nut 156A is permitted to move axially within axial slot 115A of take-up hub 152A, causing nut 156A to also move axially relative to take-up hub 152A. Thus, rotation of take-up hub 152A relative to base 154A results in axial movement of nut 156A relative to take-up hub 152A and base 154A, and further axial movement of nut 156A toward compression spring 158A axially compresses compression spring 158A. Because take-up hub 152A is rotationally locked to nut 156A via splined connection 159A, nut 156A converts the axial force of compression spring 158A into torque on take-up hub 152A.The combination of compression spring 158A, nut 156A, and cam surface 155A thereby provides a torque that counteracts or opposes relative rotation between take-up hub 152A and base 154A, which acts to maintain consistent tension in upper sheet 166A.

[0108]

[0173] The take-up hub 152A is axially constrained relative to the base 154A via a clip or retaining feature 149A disposed between the shaft 157A and the take-up hub 152A. More specifically, because the compression spring 158A acts to axially separate the take-up hub 152A and the base 154A, the retaining feature 149A (best shown in FIG. 14B ) is disposed between the upper end of the take-up hub 152A and the compression spring 158A to maintain the correct relative axial position between the take-up hub 152A and the base 154A. The retaining feature 149A may be a clip, bayonet, or other component suitable for maintaining the correct relative axial position between the take-up hub 152A and the base 154A. In another embodiment (not shown), the retaining feature may be mounted inside the housing 102 to maintain the correct relative axial position between the take-up hub 152A and the base 154A.

[0109]

[0174] FIG. 14E illustrates how the position of nut 156A changes over the life of the device. In its initial assembled state, shown in the image on the left, nut 156A rests on the lower end of cam surface 155A prior to attachment of take-up hub 152A to first blister strip 160A. Cam surface 155A is designed so that in this position, no torque develops between take-up hub 152A and base 154A, even in the presence of a potential axial force from compression spring 158A. When the device is assembled, top sheet 166A is assembled under some tension to ensure effective release from the first dose, resulting in nut 156A lifting cam surface 155A slightly away from vertical surface 111A of cam surface 155A. More specifically, as shown in the middle image, when the device is assembled, top sheet 166A is attached to take-up hub 152A, and as take-up hub 152A rotates relative to base 154A, nut 156A moves up cam surface 155A. Compression spring 158A is deflected or slightly compressed from its uncompressed length so that compression spring 158A has a preload force. The preload force ensures that the tension in top sheet 166A of first blister strip 160A is high enough to peel top sheet 166A from bottom sheet 162A of first blister strip 160A at the beginning of device life. The specifications of the compression spring 158A and the angle of the cam surface 155A should be configured to provide a minimum tension on the top sheet 166A of the first blister strip 160A that is higher than the maximum force required to peel the top sheet 166A of the first blister strip 160A from the bottom sheet 162A of the first blister strip 160A. In this assembled state, the combination of the compression spring 158A, nut 156A, and cam surface 155A provides a torque between the base 154A and the take-up hub 152A that is counteracted by the tension in the top sheet 166A. Over the life of the inhalation device 100, as shown in the image to the right, the tension in the top sheet 166A of the first blister strip 160A increases.The increased tension in the upper seat 166A causes the nut 156A to move further up the cam surface 155A, so that the increased tension in the upper seat 166A is balanced by further deflection of the compression spring 158A.

[0110]

[0175] The angle or slope of each inclined surface 113A of cam surface 155A is configured to maintain consistent sheet tension on top sheets 166A, 166B over the life of the device. As discussed above, top sheets 166A, 166B must be under consistent tension to ensure proper operation of inhalation device 100. Generally, the angle or slope of each inclined surface 113A of cam surface 155A is selected to ensure that nut 156A moves along cam surface 155A of base 154A during operation of inhalation device 100 and does not move past or pass over vertical surface 111A. In one embodiment, inclined surface 113A of cam surface 155A extends at an angle between 35 degrees and 55 degrees relative to the longitudinal axis of base 154A. In one embodiment, inclined surface 113A of cam surface 155A extends at an angle between 40 degrees and 50 degrees relative to the longitudinal axis of base 154A. In one embodiment, inclined surface 113A of cam surface 155A extends at an angle of approximately 45 degrees relative to the longitudinal axis of base 154A, including a tolerance of approximately 3 degrees as used herein. In one embodiment, inclined surface 113A of cam surface 155A has a slope of 0.70 to 1.0. In one embodiment, inclined surface 113A of cam surface 155A has a slope of 0.80 to 0.95. In another embodiment, inclined surface 113A of cam surface 155A has a slope of 0.7 to 1.4. In another embodiment, inclined surface 113A of cam surface 155A has a slope of 1.0 to 1.4. The slope of inclined surface 113A of cam surface 155A may be constant over the length of the inclined surface or may vary over the length of the inclined surface.

[0111]

[0176] The radial width of the inclined surfaces 113A of the cam surface 155A is configured to optimize the amount of friction between the nut 156A and the cam surface 155A. Generally, the larger the radial width of the inclined surfaces 113A of the cam surface 155A, the greater the friction between the components, and the smaller the radial width of the inclined surfaces 113A of the cam surface 155A, the greater the likelihood that the nut 156A will undesirably fall off the cam surface 155A. In one embodiment, each inclined surface 113A of the cam surface 155A has a radial width between 1 mm and 3 mm. In one embodiment, each inclined surface 113A of the cam surface 155A has a radial width between 1.5 mm and 2.5 mm. In one embodiment, each inclined surface 113A of the cam surface 155A has a radial width of approximately 2 mm, which, as used herein, includes a tolerance of approximately 0.2 mm.

[0112]

[0177] Compared to tensioning mechanisms that utilize torsion springs to maintain consistent sheet tension, the use of compression springs 158A within tensioning mechanism 151A can reduce the cost and environmental impact of inhalation device 100 and can result in simpler assembly and / or manufacturing of inhalation device 100. In particular, for example, compression springs 158A do not require hooks or legs that need to be formed on the ends of torsion springs. Without legs to engage with retention features, compression springs 158A can be significantly easier to manufacture and / or assemble than torsion springs. Furthermore, compression springs 158A are believed to generate a more axisymmetric and balanced torque on take-up hub 152A compared to mechanisms that utilize torsion springs, such that take-up hubs according to embodiments of the present invention are less prone to rocking off-axis, which can cause tangling or dragging of the top sheet of the blister strip as it moves axially and wraps around the take-up hub.

[0113]

[0178] Those skilled in the art will understand that the relative dimensions and / or placement of the various components of tensioning mechanism 151A may differ from those shown in the embodiment of Figures 14A-14E. Variations in the relative dimensions and / or placement of the various components may result in different mechanical characteristics of the mechanism due to differences in properties such as contact radius, cam surface slope, and compression spring specifications. Variations in the relative dimensions and / or placement of the various components provide alternative options that may be desirable in some applications depending on factors such as space requirements, manufacturing or assembly methods, etc.

[0114]

[0179] 15A and 15B illustrate another embodiment of a tensioning mechanism 1551 having different relative dimensions than tensioning mechanism 151A. Tensioning mechanism 1551 includes a hub 1552, a base 1554 having a camming surface 1555 integrally formed therewith or affixed thereto, a nut 1556, a shaft 1557, and a compression spring 1558 extending or disposed between the nut 1556 and an end of take-up hub 1552 spaced from base 1554. Take-up hub 1552 is axially constrained relative to base 1554 via a clip or retaining feature 1549 disposed between shaft 1557 and take-up hub 1552. Tensioning mechanism 1551 operates in the same manner as tensioning mechanism 151A described above, except that in this embodiment, camming surface 1555 on base 1554 has a larger diameter than the diameter of compression spring 1558. Stated another way, cam surface 1555 has a first outer diameter OD1 and compression spring 1558 has a second outer diameter OD2, where the first outer diameter is larger than the second outer diameter. This arrangement may result in different mechanical characteristics of tensioning mechanism 1551 due to differences in contact radius, cam surface slope, and compression spring specifications.

[0115]

[0180] 16A and 16B illustrate another embodiment of a tensioning mechanism 1651 whose components are arranged differently than the components of tensioning mechanism 151A. Tensioning mechanism 1651 includes a hub 1652, a base 1654, a nut 1656, a shaft 1657, and a compression spring 1658. Take-up hub 1652 is axially constrained relative to base 1654 via a clip or retaining feature 1649 disposed between shaft 1657 and take-up hub 1652. Tensioning mechanism 1651 provides a similar function to tensioning mechanism 151A described above, except that in this embodiment, cam surface 1655 is integrally formed with or fixed to the inner periphery of take-up hub 1652. To interact with the cam surface 1655, the nut 1656 includes a plurality of outwardly extending ribs 1619 that protrude or extend radially outward from the outer periphery of the nut 1656. A compression spring 1658 extends or is disposed between the nut 1656 and the base 1654 and biases the nut 1656 upward into the cam surface 1655. Additionally, in this embodiment, the nut 1656 is rotationally locked to the base 1654, such that the nut 1656 is only permitted to move axially relative to the base 1654. Stated another way, the nut 1656 is not permitted to rotate relative to the base 1654. Nut 1656 is rotationally locked to base 1654 via a splined connection (not shown) that includes inwardly extending ribs that protrude or extend radially outward from the inner periphery of nut 1656 and are received in axial slots in shaft 1657, similar to the configuration of nut 156A shown in FIG. 14D . The inwardly extending ribs are permitted to slide or move axially along the axial slots such that nut 1656 is permitted to slide or move axially relative to shaft 1657 and attached base 1654, but the inwardly extending ribs do not permit nut 1656 to rotate relative to shaft 1657 and base 1654.

[0116]

[0181] Cam surface 1655, nut 1656, and compression spring 1658 interact to accomplish the same function as cam surface 155A, nut 156A, and compression spring 158A, thereby providing a constant driving tension to first blister strip 160A throughout the entire strip length. As tension along top sheet 166A increases, take-up hub 1652 rotates relative to base 1654, reducing tension along top sheet 166A.

[0117]

[0182] As the base 1654 rotates with an upper sheet take-up gear, such as first upper sheet take-up gear 150A, the nut 1656 and take-up hub 1652 also rotate in the same direction as the base 1654 due to the interaction of the nut 1656 with the compression spring 1658 and the cam surface 1655 of the take-up hub 1652. Furthermore, relative rotation is permitted between the take-up hub 1652 and the base 1654. More specifically, when sufficient torque is applied between the take-up hub 1652 and the base 1654, the take-up hub 1652 rotates relative to the base 1654. Because the take-up hub 1652 is permitted to rotate relative to the base 1654 in a direction that reduces tension in an upper sheet, such as upper sheet 166A, this relative rotation stabilizes or balances the tension in the upper sheet via deflection of the compression spring 1658. Thus, tensioning mechanism 1651 acts as a torsion or torque limiter between take-up hub 1652 and base 1654 to control the tension in the top sheet of blister strips, such as first blister strip 160A.

[0118]

[0183] As the tension on the top sheet of the blister strip increases, the torque that the top sheet applies to the take-up hub 1652 also increases. Rather than continuing to increase the torque, the take-up hub 1652 begins to rotate relative to the base 1654, causing the nut 1656 to spiral down the cam surface 1655 of the take-up hub 1652, thereby compressing the compression spring 1658. More specifically, as the take-up hub 1652 begins to rotate due to the increased tension on the top sheet of the blister strip, the outwardly extending rib 1619 of the nut 1656 moves along the inclined surface of the cam surface 1655 toward the compression spring 1658. The compression spring 1658 compresses as the nut 1656 presses against it. The inwardly extending rib of the nut 1656 is allowed to move axially within the axial slot of the shaft 1657, causing the nut 1656 to move axially relative to the base 1654. Thus, rotation of the take-up hub 1652 relative to the base 1654 results in downward axial movement of the nut 1656 relative to the upper surface of the take-up hub 1652 and toward the base 1654, and further axial movement of the nut 1656 axially compresses the compression spring 1658. The nut 1656 converts the axial force of the compression spring 1658 into torque on the take-up hub 1652. The combination of the compression spring 1658, nut 1656, and cam surface 1655 thereby provides a torque that counteracts relative rotation between the take-up hub 1652 and the base 1654, which acts to maintain consistent tension in the top sheet of the blister strip.

[0119]

[0184] 17A and 17B illustrate another embodiment of a tensioning mechanism 1751 whose components are arranged differently than the components of tensioning mechanism 151A. Tensioning mechanism 1751 includes a hub 1752, a base 1754 having an integrally formed or affixed cam surface 1755, a nut 1756, a shaft 1757, and a compression spring 1758. Take-up hub 1752 is axially constrained relative to base 1754 via a clip or retaining feature 1749 disposed between shaft 1757 and take-up hub 1752. Tensioning mechanism 1751 provides the same function as tensioning mechanism 151A described above, but in a different manner. In this embodiment, compression spring 1758 extends or is disposed between nut 1756 and base 1754 and biases nut 1756 upward into cam surface 1755.

[0120]

[0185] Cam surface 1755, nut 1756, and compression spring 1758 function in the same manner as cam surface 155A, nut 156A, and compression spring 158A to provide a constant driving tension to a blister strip, such as first blister strip 160A, throughout the entire length of the strip. Increasing tension along a top sheet of the blister strip, such as top sheet 166A, results in rotation of take-up hub 1752 relative to base 1754 to reduce the tension along the top sheet of the blister strip.

[0121]

[0186] As the base 1754 rotates with an upper sheet take-up gear, such as first upper sheet take-up gear 150A, the nut 1756 and take-up hub 1752 also rotate in the same direction as the base 1754 due to the interaction of the nut 1756 with the compression spring 1758 and the cam surface 1755. Furthermore, relative rotation between the take-up hub 1752 and the base 1754 is permitted. More specifically, when sufficient torque is applied between the take-up hub 1752 and the base 1754, the take-up hub 1752 rotates relative to the base 1754. Because the take-up hub 1752 is permitted to rotate relative to the base 1754 in a direction that reduces tension in an upper sheet, such as upper sheet 166A, this relative rotation stabilizes or balances the tension in the upper sheet via deflection of the compression spring 1758. Thus, tensioning mechanism 1751 acts as a torsion or torque limiter between take-up hub 1752 and base 1754 to control the tension in the top sheet of blister strips, such as first blister strip 160A.

[0122]

[0187] As the tension on the top sheet of the blister strip increases, the torque that the top sheet applies to the take-up hub 1752 also increases. Rather than continuing to increase the torque, the take-up hub 1752 begins to rotate relative to the base 1754, causing the nut 1756 to spiral down the cam surface 1755, thereby compressing the compression spring 1758. More specifically, as the take-up hub 1752 begins to rotate due to the increased tension on the top sheet of the blister strip, the inwardly extending rib of the nut 1756 moves downward along the sloped surface of the cam surface 1755 toward the compression spring 1758. The compression spring 1758 compresses as the nut 1756 presses against it. The nut 1756 moves axially relative to the base 1754 because the outwardly extending ribs of the nut 1756 are allowed to move axially within the axial slots of the take-up hub 1752 (similar to the splined coupling arrangement between the nut 156A and the take-up hub 152A). Thus, rotation of the take-up hub 1752 relative to the base 1754 results in downward axial movement of the nut 1756 against the top surface or wall of the take-up hub 1752 and toward the base 1754; further axial movement of the nut 1756 toward the compression spring 1758 axially compresses the compression spring 1758. The nut 1756 converts the axial force of the compression spring 1758 into torque in the take-up hub 1752. The combination of compression spring 1758, nut 1756 and cam surface 1755 thereby provides a torque that counteracts relative rotation between take-up hub 1752 and base 1754, which acts to maintain consistent tension in the top sheet of the blister strip.

[0123]

[0188] 18-20 illustrate another embodiment of a tensioning mechanism or subassembly that may be utilized within inhalation device 100. Similar to tensioning mechanism 151A described above, tensioning mechanism 1851 functions to peel top sheet 166A from blister strip 160A to maintain a consistent peel distance or amount over the life of the device. Tensioning mechanism 1851 also functions to maintain sheet tension in top sheet 166A over the life of the device. Tensioning mechanism 1851 is associated with an upper sheet take-up gear, such as first upper sheet take-up gear 150A, for winding top sheet 166A of blister strip 160A. It should be understood that in inhalation device 100, each of first tensioning mechanism 151A and second tensioning mechanism 151B may be replaced by tensioning mechanism 1851 without departing from the scope of the present disclosure.

[0124]

[0189] In this embodiment, the upper sheet take-up gear is integrally formed with or secured to the take-up hub 1852 and rotates as an assembly. The upper sheet 166A of the blister strip 160A is secured or attached to the take-up hub 1852 via hooks 1853 so that as the first take-up hub 1852 rotates, the upper sheet 166A of the blister strip 160A wraps around it. As described above, as the take-up hub 1852 completes multiple rotations over the life of the inhalation device 100, the upper sheet 166A of the blister strip 160A wraps around itself multiple times, increasing its radial position on the take-up hub 1852.

[0125]

[0190] The tensioning mechanism 1851 includes a slider 1861 and at least one compression spring 1858 attached to the slider 1861. The tensioning mechanism 1851 is disposed between the take-up hub 1852 and an indexing spool, such as the first indexing spool 131A, and is configured to adjust the length of the upper sheet 166A between the take-up hub 1852 and the first indexing spool 131A to maintain consistent tension on the upper sheet 166A, thereby compensating for winding effects and component tolerances. As described in more detail herein, the tensioning mechanism 1851 applies a non-parallel force to a portion of the upper sheet 166A via the compression spring 1858. The tensioning mechanism 1851 is coupled to the housing 102 of the inhalation device 100 to permit axial movement of the slider 1861 relative to the housing 102 along a predetermined path 1863. The slider 1861 is configured to receive and guide an intermediate portion of the top sheet 166A, the intermediate portion being disposed between the first indexing spool 131A and the take-up hub 1852. Increasing tension along the top sheet 166A results in axial movement of the slider along a predetermined path 1863, which axially compresses the compression spring 1858, reducing the tension along the top sheet 166A.

[0126]

[0191] More specifically, slider 1861 is coupled to housing 102 of inhalation device 100 such that slider 1861 can move relative to housing 102 along a predetermined path 1863. As best shown in FIG. 19B , predetermined path 1863 is formed by a recess in the inner surface of housing 102 and is linear. In another embodiment (not shown), predetermined path 1863 may be non-linear. For example, predetermined path 1863 may be curved to allow for better space efficiency within inhalation device 100 and / or adjustment of the mechanical properties of tensioning mechanism 1851 over the life of the device.

[0127]

[0192] A compression spring 1858 is disposed to act between the slider 1861 and the housing 102 and provides a force acting in a direction along a predetermined path 1863. A first end 1807 of the compression spring 1858 is attached or fixed to the slider 1861, and a second end 1809 of the compression spring 1858 is attached or fixed to the housing 102. The top sheet 166A of the blister strip 160A passes from the first indexing spool 131A around the slider 1861 and is attached to the take-up hub 1852 as described above. The axial force of the compression spring 1858 urges the slider 1861 away from the first indexing spool 131A and the take-up hub 1852. Stated another way, the compression spring 1858 is biased to push the slider 1861 away from each of the first indexing spool 131A and the take-up hub 1852. As a result, the length of the top sheet 166A between the first indexing spool 131A and the take-up hub 1852 is affected by the position of the slider 1861 within its available travel along the predetermined path 1863. Referring to FIG. 19A , as the compression spring 1858 relaxes somewhat and at a longer length, the slider 1861 moves further away from each of the first indexing spool 131A and the take-up hub 1852, such that there is a greater or longer length of the top sheet 166A extending between the first indexing spool 131A and the take-up hub 1852. Conversely, referring to FIG. 19B, when the compression spring 1858 is compressed and at a shorter length, the slider 1861 is spaced closer to the first index spool 131A and the take-up hub 1852, thereby resulting in a shorter length of the upper seat 166A extending between the first index spool 131A and the take-up hub 1852.

[0128]

[0193] During each dose, the first indexing spool 131A rotates in a first direction (e.g., clockwise) with its indexing gear, such as first indexing gear 130A, and the take-up hub 1852 rotates in a second, opposite direction (e.g., counterclockwise) with its upper sheet take-up gear, such as upper sheet take-up gear 150A, as described above. As the first indexing spool 131A and take-up hub 1852 are driven in opposite directions, the top sheet 166A is pulled around the slider 1861 and peeled off from the bottom sheet 162A, which is moving clockwise with the first indexing spool 131A. Due to the wrapping effect described above, the radial position of the top sheet 166A of the blister strip 160A increases as the take-up hub 1852 rotates. As a result of this increased radial position, the take-up hub 1852 attempts to peel a longer length of top sheet 166A, and the tension on top sheet 166A increases due to the change in the peel angle between the top sheet 166A of blister strip 160A and the bottom sheet 162A of the first blister strip 160A. As the take-up hub 1852 begins to pull on top sheet 166A further, the reaction force at the peel edge increases, thereby increasing the tension in top sheet 166A. The tensioning mechanism 1851 ensures that the same amount of top sheet 166A of blister strip 160A is peeled off with each dose. To do so, the increased tension in top sheet 166A acts to pull or move slider 1861 toward indexing spool 131, against the force from compression spring 1858. As the slider 1861 moves toward the first indexing spool 131A, the length of the top sheet 166A extending between the first indexing spool 131A and the take-up hub 1852 decreases, thereby reducing the reaction force at the peel edge. The movement of the slider 1861 is illustrated by comparing Figures 19A and 19B. The axial movement of the slider 1861 (from the increased tension in the top sheet 166A) causes the compression spring 1858 to compress axially, reducing the tension along the top sheet 166A, and the axial compression of the compression spring 1858 moves the slider 1861 closer to each of the first indexing spool 131A and the take-up hub 1852.The tensioning mechanism stabilizes when the force from the compression spring 1858 balances the upper sheet tension, which in turn balances the reaction force at the peel edge. In this way, the tension in the upper sheet 166A is maintained at a relatively consistent level by the tensioning mechanism throughout the life of the device. The tensioning mechanism 1851 stabilizes or balances the tension in the upper sheet 166A through the compression of the compression spring 1858 and the movement of the slider 1861.

[0129]

[0194] Figure 20 illustrates the performance characteristics of the tensioning mechanism 1851. The graph in Figure 20 shows the increase in radial position of the upper sheet 166A over the life of the device and the cumulative length compensation of the upper sheet 166A achieved by movement of the slider 1861. The graph also shows the estimated tension in the upper sheet 166A over the life of the device. Although the upper sheet tension may increase gradually due to the stiffness of the compression spring 1858, as shown, the upper sheet tension remains substantially constant or constant over the life of the device.

[0130]

[0195] Those skilled in the art will appreciate that the relative dimensions and / or arrangement of the various components of the tensioning mechanism 1851 may differ from those shown in the embodiment of Figures 18-20. Different performance characteristics of the tensioning mechanism 1851 can be achieved through variations in component geometry, arrangement, and compression spring specifications. For example, a compression spring with a longer solid height and lower stiffness can be utilized. Such a compression spring may occupy more space within the inhalation device but may provide more consistent upper sheet tension over the life of the device. Varying the relative dimensions and / or arrangement of the various components provides alternative options that may be desirable in some applications, depending on factors such as space requirements, manufacturing or assembly methods, etc.

[0131]

[0196] When the compression spring 1858 is in its initially assembled state within the inhalation device 100 and the top sheet 166A is attached to the take-up hub 1852, the compression spring 1858 is deflected or slightly compressed from its uncompressed length such that the compression spring 1858 applies a preload force. The preload force ensures that the tension in the top sheet 166A of the blister strip 160A at the beginning of the device's life is high enough to peel the top sheet 166A from the bottom sheet 162A of the blister strip 160A. The specifications and surrounding geometry of the compression spring 1858 should be configured to provide a minimum tension in the top sheet 166A of the blister strip 160A that is higher than the maximum force required to peel the top sheet 166A of the first blister strip 160A from the bottom sheet 162A of the blister strip 160A.

[0132]

[0197] In the embodiment depicted in Figures 18-20, the compression spring 1858 is a single spring. However, the compression spring 1858 may include two or more springs. For example, in another embodiment, the compression spring 1858 includes exactly two springs used in parallel or coaxially. Utilizing two parallel or coaxial compression springs may allow the solid height of the springs to be shorter for the same combined stiffness, thus reducing the physical footprint of the tensioning mechanism.

[0133]

[0198] Additionally, in another embodiment, one or more tension springs can be utilized as an alternative to the compression spring 1858. The tension springs are positioned relative to the slider such that axial movement of the slider stretches the tension spring axially toward the first indexing spool 131A, reducing tension along the top sheet of the blister strip. Tension springs may be desirable in some device layouts for space efficiency. Additionally, in another embodiment, one or more torsion springs can be utilized as an alternative to the compression spring 1858. When a tension or torsion spring is utilized as an alternative to the compression spring 1858, the spring(s) act between the slider and the housing and provide a force that moves the slider away from the indexing gear (i.e., increases the length of the top sheet between the indexing gear and the take-up hub). In the case of a torsion spring, it may be desirable to move the slider in an arcuate path rather than a linear path so that the slider remains concentric with the axis of the torsion spring and maintains more consistent operation.

[0134]

[0199] While in the embodiment of FIGS. 18-20 , the take-up hub 1852 is driven to rotate in the opposite direction to the indexing gear 130A, in another embodiment, the take-up hub 1852 can be driven to rotate in the same direction as the indexing gear 130A by adding an idler gear (not shown) disposed between the indexing gear 130A and the take-up gear 150A. When the indexing gear 130A and the take-up hub 1852 both rotate in the same direction (i.e., the first or clockwise direction), the upper sheet 166A wraps around the take-up hub 1852 in the first direction, which causes the angle of the upper sheet 166A to approach the angle of movement of the slider 1861. As a result, the same amount of slider movement results in a greater change in the length of the upper sheet 166A. The reduced overall movement of the slider 1861 results in a smaller physical footprint for the tensioning mechanism and / or more consistent sheet tension.

[0135]

[0200] In contrast to tensioning mechanism 151A, the components of tensioning mechanism 1851 are not retained or housed within take-up hub 1852. The unhoused or exposed nature of slider 1861 and compression spring 1858 allows for the incorporation of various spring sizes and specifications without changing the geometry or size of take-up hub 1852, which may be useful for optimizing the tensioning mechanism for different blister strip designs and specifications. The unhoused or exposed nature of slider 1861 and compression spring 1858 also allows for improved inspection of the success of the assembly process and the condition of the tensioning mechanism during assembly, reducing the risk of undetected assembly errors.

[0136]

[0201] 21-23B illustrate another embodiment of a tensioning mechanism or subassembly 2151 that may be utilized within inhalation device 100. Similar to the tensioning mechanisms described above, tensioning mechanism 2151 functions to peel top sheet 166A from blister strip 160A to maintain a consistent peel distance or amount over the life of the device. Tensioning mechanism 2151 also functions to maintain sheet tension on top sheet 166A over the life of the device. Tensioning mechanism 2151 is associated with an upper sheet take-up gear, such as first upper sheet take-up gear 150A, for winding top sheet 166A of blister strip 160A. It should be understood that in inhalation device 100, each of first tensioning mechanism 151A and second tensioning mechanism 151B may be replaced by tensioning mechanism 2151 without departing from the scope of the present disclosure.

[0137]

[0202] In this embodiment, the upper sheet take-up gear is integrally formed with or secured to the take-up hub 2152 and rotates as an assembly. The upper sheet 166A of the blister strip 160A is secured or attached to the take-up hub 2152 via hooks 2153 so that as the take-up hub 2152 rotates, the upper sheet 166A of the blister strip 160A wraps around it. As described above, as the take-up hub 2152 completes multiple rotations over the life of the inhalation device 100, the upper sheet 166A of the blister strip 160A wraps around itself multiple times, increasing its radial position on the take-up hub 2152.

[0138]

[0203] The tensioning mechanism 2151 is fixed to an interior surface, wall, or component of the housing 102 and includes a pin 2165 extending therefrom, a bracket 2101, and at least one tension spring 2158 attached to the bracket 2101. The tensioning mechanism 2151 is configured to adjust the length of the top sheet 166A between the take-up hub 2152 and the first indexing spool 131A to maintain consistent tension on the top sheet 166A, thereby compensating for winding effects and component tolerances. As described in more detail herein, the tensioning mechanism 2151 maintains constant tension on the top sheet 166A by allowing movement of the take-up hub 2152 (and the top sheet 166A mounted thereon) via the tension spring 2158, which is biased substantially away from the take-up hub 2152 and the top sheet 166A wrapped therearound. The take-up hub 2152 is coupled to the housing 102 of the inhalation device 100 to permit movement of the take-up hub 2152 relative to the housing 102 along a predetermined path 2163. The pin 2165 is configured to receive and guide an intermediate portion of the upper seat 166A, the intermediate portion being disposed between the first indexing spool 131A and the take-up hub 2152. An increase in tension along the upper seat 166A results in movement of the take-up hub 2152 along the predetermined path 2163, which causes the tension spring 2158 to axially lengthen or elongate, thereby reducing the tension along the upper seat 166A.

[0139]

[0204] More specifically, the take-up hub 2152 is coupled to the housing 102 of the inhalation device 100 so as to be movable along a predetermined path 2163 relative to the housing 102. The predetermined path 2163 is formed by a curved slot in the inner surface of the housing 102. The take-up hub 2152 extends through the curved slot, which defines the predetermined path 2163. The curved slot, which forms the predetermined path 2163, is concentric with the rotational axis of the first indexing spool 131A, causing the take-up hub 2152 to move in an arc concentric with the rotational axis of the first indexing spool 131A. As a result, as the take-up hub 2152 moves along the predetermined path 2163, the take-up gear 150A remains meshed with the indexing gear 130A.

[0140]

[0205] A pin 2165 extends radially from the inner surface of the housing 102 and is fixed to the housing. The top sheet 166A passes from the first indexing spool 131A around the pin 2165 and is attached to the take-up hub 2152. The pin 2165 is disposed adjacent the end of a curved slot that forms a predetermined path 2163. As described in more detail below, the pin 2165 is positioned within the housing 102 such that movement of the take-up hub 2152 results in a change in the length of the top sheet 166A between the take-up hub 2152 and the first indexing spool 131A.

[0141]

[0206] The take-up hub 2152 is mechanically linked or coupled to the housing 102 via a bracket 2101. The take-up hub 2152 is coupled to the bracket 2101 such that when the take-up hub 2152 is driven in rotation to wind the top sheet 166A, the take-up hub 2152 rotates relative to the bracket 2101. Similarly, the indexing gear 130A is coupled to the bracket 2101 such that when the indexing gear 130A is driven in rotation to advance the blister strip 160A, the indexing gear 130A rotates relative to the bracket 2101. The bracket 2101 has a first end 2103 (shown in FIG. 21 ) and a second end 2105 (shown in FIG. 22 ) coupled to the first indexing spool 131A to permit rotation of the bracket 2101 relative to the first indexing spool 131A. Thus, as the bracket 2101 rotates relative to the housing 102, the center of the take-up hub 2152 moves within a predetermined path 2163 of the curved slot in the housing 102. The bracket 2101 is permitted to rotate relative to the housing 102, and the bracket 2101 rotates or pivots about the index gear 130A as the take-up hub 2152 moves within the predetermined path 2163.

[0142]

[0207] A tension spring 2158 is disposed to act between the bracket 2101 and the housing 102 and provides a force urging the take-up hub 2152 away from the pin 2165 and toward one end of the predetermined path 2163 of the curved slot in the housing 102. As best shown in FIG. 22 , a first end 2107 of the tension spring 2158 is attached or fixed to the housing 102, and a second end 2109 of the tension spring 2158 is attached or fixed to the bracket 2101. The top sheet 166A of the blister strip 160A passes from the first indexing spool 131A around the pin 2165 and is attached to the take-up hub 2152 as described above. The axial force of the tension spring 2158 pulls the take-up hub 2152 away from the pin 2165. Stated another way, the tension spring 2158 is biased to position the take-up hub 2152 at the end of the curved slot opposite the pin 2165. As a result, the length of the top sheet 166A between the first indexing spool 131A and the take-up hub 2152 is affected by the position of the take-up hub 2152 within its available travel along the predetermined path 2163. Referring to FIG. 23A , as the tension spring 2158 is compressed and at a shorter length, the take-up hub 2152 is spaced further away from the pin 2165, thereby resulting in a greater or longer length of the top sheet 166A between the first indexing spool 131A and the take-up hub 2152. Conversely, referring to FIG. 23B, when the tension spring 2158 is stretched and at a longer length, the take-up hub 2152 is spaced closer to the pin 2165, thereby resulting in a shorter length of the upper seat 166A between the first index spool 131A and the take-up hub 2152.

[0143]

[0208] During each dose, the first indexing spool 131A rotates in a first direction (i.e., clockwise) with the indexing gear 130A, and the take-up hub 2152 rotates in a second, opposite direction (i.e., counterclockwise) with the top sheet take-up gear 150A as described above. As the first indexing spool 131A and take-up hub 2152 are driven in opposite directions, the top sheet 166A is pulled around the pin 2165 and peeled away from the bottom sheet 162A, which is moving clockwise with the first indexing spool 131A. Due to the wrapping effect described above, the radial position of the top sheet 166A of the blister strip 160A increases as the take-up hub 2152 rotates. As a result of this increased radial position, the take-up hub 2152 attempts to peel a longer length of top sheet 166A, and the tension on top sheet 166A increases due to the change in the peel angle between the top sheet 166A of blister strip 160A and the bottom sheet 162A of blister strip 160A. As the take-up hub 2152 begins to pull on top sheet 166A further, the reaction force at the peel edge increases, thereby increasing the tension in top sheet 166A. The tensioning mechanism 2151 ensures that the same amount of top sheet 166A of blister strip 160A is peeled off with each dose. The increased tension in top sheet 166A acts to pull or move the take-up hub 2152 toward pin 2165 along a predetermined path 2163 defined by a curved slot in housing 102, against the force from tension spring 2158. The bracket 2101 rotates relative to the housing 102 as the take-up hub 2152 moves along the predetermined path 2163. As the take-up hub 2152 moves toward the first indexing spool 131A and pin 2165, the length of the top sheet 166A between the first indexing spool 131A and the take-up hub 2152 decreases, thereby reducing the reaction force at the peel edge. The movement of the take-up hub 2152, the rotation of the bracket 2101, and the deformation of the tension spring 2158 are illustrated by comparing Figures 23A and 23B.Movement of the take-up hub 2152 (from increasing tension in the upper sheet 166A) causes the tension spring 2158 to extend or lengthen axially, reducing tension along the upper sheet 166A and causing the take-up hub 2152 to move closer to the first indexing spool 131A and pin 2165, respectively. The tensioning mechanism stabilizes when the force from the tension spring 2158 balances the upper sheet tension, which in turn balances the reaction force at the peel edge. In this way, tension in the upper sheet 166A is maintained at a relatively consistent level by the tensioning mechanism throughout the life of the device. The tensioning mechanism 2151 stabilizes or balances the tension in the upper sheet 166A through the extension of the tension spring 2158 and the movement of the take-up hub 2152.

[0144]

[0209] When the tension spring 2158 is initially assembled within the inhalation device 100 and the top sheet 166A is attached to the take-up hub 2152, the tension spring 2158 is deflected or slightly extended from its compressed length such that the tension spring 2158 applies a preload force. The preload force ensures that the tension in the top sheet 166A of the blister strip 160A at the beginning of the device's life is high enough to peel the top sheet 166A from the bottom sheet 162A of the blister strip 160A. The specifications and surrounding geometry of the tension spring 2158 should be configured to provide a minimum tension in the top sheet 166A of the blister strip 160A that is higher than the maximum force required to peel the top sheet 166A of the blister strip 160A from the bottom sheet 162A of the blister strip 160A.

[0145]

[0210] 22, the tension spring 2158 is aligned or disposed with the centerline of the take-up hub 2152 and, therefore, the centerline of the top sheet 166A that wraps around it. This alignment between the tension spring 2158 and the centerline of the top sheet 166A minimizes the torque on the bracket 2101 as it rotates with the movement of the take-up hub 2152.

[0146]

[0211] In contrast to tensioning mechanism 151A, the components of tensioning mechanism 2151 are not retained or housed within take-up hub 2152. The unhoused or exposed nature of bracket 2101 and tension spring 2158 allows for the incorporation of various spring sizes and specifications without changing the geometry or size of take-up hub 2152, which may be useful for optimizing the tensioning mechanism for different blister strip designs and specifications. The unhoused or exposed nature of bracket 2101 and tension spring 2158 also allows for improved inspection of the success of the assembly process and the condition of the tensioning mechanism during assembly, reducing the risk of undetected assembly errors.

[0147]

[0212] Those skilled in the art will understand that the relative dimensions and / or placement of the various components of the tensioning mechanism 2151 may differ from that shown in the embodiment of Figures 21-23B. Variations in the relative dimensions and / or placement of the various components provide alternative options that may be desirable in some applications depending on factors such as space requirements, manufacturing or assembly methods, etc.

[0148]

[0213] 24 and 25 illustrate another embodiment of a tensioning mechanism or subassembly 2451 that may be utilized within inhalation device 100. Tensioning mechanism 2451 functions similarly to tensioning mechanism 2151, but utilizes two torsion springs 2458, 2458A instead of tension spring 2158 and bracket 2101. A first torsion spring 2458 is positioned to interact with a first side of take-up hub 2452, and a second torsion spring 2458A is positioned to interact with a second, opposite side of take-up hub 2452. While it is believed that utilizing two torsion springs acting on opposite sides of take-up hub 2452 may provide better positional stability of take-up hub 2452, in other embodiments of the present invention, tensioning mechanism 2451 may include only a single torsion spring acting on a single side of take-up hub 2452. Torsion springs 2458, 2458A function similarly to tension spring 2158, providing a force that biases take-up hub 2452 away from pin 2465. Furthermore, in this embodiment, take-up hub 2452 is constrained within two arcuate slots 2433, 2433A in housing 102 rather than via a bracket. While the functional principle is similar to tensioning mechanism 2151, tensioning mechanism 2451 has a different physical footprint compared to tensioning mechanism 2151, as well as different advantages in terms of assembly complexity, robustness, cost, etc.

[0149]

[0214] The tensioning mechanism 2451 includes several components that are the same as the components of the tensioning mechanism 2151 and will not be described in detail. More specifically, the take-up hub 2452 is the same as the take-up hub 2152, the pin 2465 is the same as the pin 2165, and the predetermined path 2463 is the same as the predetermined path 2163. The take-up hub 2452 is coupled to the housing 102 of the inhalation device 100 to allow movement of the take-up hub 2452 relative to the housing 102 along the predetermined path 2463. The pin 2465 is configured to receive and guide an intermediate portion of the upper sheet 166A, the intermediate portion being disposed between the first indexing spool 131A and the take-up hub 2452. An increase in tension along the upper sheet 166A results in movement of the take-up hub 2452 along the predetermined path 2463.

[0150]

[0215] A first leg 2407, 2407A of each torsion spring 2458, 2458A is fixed to the inner surface of the housing 102, and a second leg 2409, 2409A of each torsion spring 2458, 2458A is coupled to the take-up hub 2452 for movement in conjunction with the take-up hub 2452 along a predetermined path 2463 defined by the curved slot. The body of each torsion spring 2458, 2458A is disposed concentrically with the axis of rotation of the indexing spool 131. Each torsion spring 2458, 2458A is biased to position the take-up hub 2452 at the end of the predetermined path 2463 defined by the curved slot opposite the pin 2465. Movement of take-up hub 2452 in a direction toward pin 2465 twists torsion springs 2458, 2458A, reducing tension along top sheet 166A of blister strip 160A, as will be explained in more detail below.

[0151]

[0216] Each torsion spring 2458, 2458A is disposed to act between the take-up hub 2452 and the housing 102 and provides a force that pulls the take-up hub 2452 toward the end of the predetermined path 2463 of the curved slot in the housing 102, i.e., away from the pin 2465. More specifically, as shown in FIG. 24 , a first leg 2407 of the first torsion spring 2458 is attached or fixed to the housing 102, and a second leg 2409 of the first torsion spring 2458 is attached or fixed to the take-up hub 2452. Similarly, as shown in FIG. 25 , a first leg 2407A of the second torsion spring 2458A is attached or fixed to the housing 102, and a second leg 2409A of the second torsion spring 2458A is attached or fixed to the take-up hub 2452. Top sheet 166A of blister strip 160A passes from first indexing spool 131A, around pin 2465, and is attached to take-up hub 2452. The force of torsion springs 2458, 2458A pulls take-up hub 2452 away from pin 2465. Stated another way, torsion springs 2458, 2458A are biased to position take-up hub 2452 at the end of the curved slot opposite pin 2465. As a result, the length of top sheet 166A between first indexing spool 131A and take-up hub 2452 is affected by the position of take-up hub 2452 within its available travel along predetermined path 2463.

[0152]

[0217] During each dose, the first indexing spool 131A rotates in a first direction (i.e., clockwise) with the indexing gear 130A, and the take-up hub 2452 rotates in a second, opposite direction (i.e., counterclockwise) with the top sheet take-up gear 150A as described above. As the first indexing spool 131A and take-up hub 2452 are driven in opposite directions, the top sheet 166A is pulled around the pin 2465 and peeled away from the bottom sheet 162A, which is moving clockwise with the first indexing spool 131A. Due to the wrapping effect described above, the radial position of the top sheet 166A of the blister strip 160A increases as the take-up hub 2452 rotates. As a result of this increased radial position, the take-up hub 2452 attempts to peel a longer length of top sheet 166A, and the tension on top sheet 166A increases due to the change in the peel angle between the top sheet 166A of blister strip 160A and the bottom sheet 162A of blister strip 160A. As the take-up hub 2452 begins to pull on top sheet 166A further, the reaction force at the peel edge increases, thereby increasing the tension in top sheet 166A. The tensioning mechanism 2451 ensures that the same amount of top sheet 166A of blister strip 160A is peeled off with each dose. The increased tension in top sheet 166A acts to pull or move the take-up hub 2452 toward pin 2465 along a predetermined path 2463 defined by a curved slot in housing 102, against the force from torsion springs 2458, 2458A. As the take-up hub 2452 moves toward the first indexing spool 131A and pin 2465, the length of the top sheet 166A between the first indexing spool 131A and the first take-up hub 2452 decreases, thereby reducing the reaction force at the peel edge. The movement of the take-up hub 2452 (from the increased tension in the top sheet 166A) twists the torsion springs 2458, 2458A, reducing the tension along the top sheet 166A and moving the take-up hub 2452 closer to the first indexing spool 131A and pin 2465, respectively.The tensioning mechanism stabilizes when the force from the torsion springs 2458, 2458A balances the upper sheet tension, which in turn balances the reaction force at the peel edge. In this way, the tension in the upper sheet 166A is maintained at a relatively consistent level by the tensioning mechanism throughout the life of the device. The tensioning mechanism 2451 stabilizes or balances the tension in the upper sheet 166A through the twisting of the torsion springs 2458, 2458A and the movement of the take-up hub 2452.

[0153]

[0218] 26A-26N illustrate another embodiment of a tensioning mechanism 2651 that operates similarly to tensioning mechanism 151A described above, except that in this embodiment, the retention feature that axially restrains the take-up hub relative to the base is a bayonet connection. Similar to tensioning mechanism 151A, tensioning mechanism 2651 includes a hub 2652, a base 2654 having an integrally formed or affixed cam surface 2655, a nut 2656, a shaft 2657, and a compression spring 2658 extending or disposed between the nut 2656 and an end of the take-up hub 2652 spaced from the base 2654. The compression spring 2658 biases the nut 2656 downward toward the base 2654 and into the cam surface 2655. The compression spring 2658 is disposed around or around the shaft 2657 and is longitudinally or axially adjacent to the nut 2656, and the take-up hub 2652 is disposed around or around the nut 2656 and the compression spring 2658. In other words, the take-up hub 2652 surrounds or encircles the nut 2656 and compression spring 2658 housed therein.

[0154]

[0219] The base 2654 is attached to or integrally formed with the first upper sheet take-up gear 2650 and rotates as an assembly when the first upper sheet take-up gear 2650 is driven in rotation. For example, the base 2654 may include a plurality of gear teeth integrally formed or affixed to its outer periphery to form the first upper sheet take-up gear 2650. The shaft 2657 extends from the base 2654 and is attached to or integrally formed with the base 2654 so as to rotate with the base 2654. As a result, when the first upper sheet take-up gear 2650 is driven in rotation, the shaft 2657, base 2654, and first upper sheet take-up gear 2650 rotate as an assembly. The cam surface 2655 of the shaft 2657 includes alternating sections of vertical surfaces 2611 and inclined surfaces 2613. The vertical surfaces 2611 extend generally parallel to the longitudinal axis of the shaft 2657. In this embodiment, the cam surface 2655 includes a total of two vertical surfaces 2611 disposed at opposite positions on the shaft 2657 and two angled surfaces 2613 disposed at opposite positions on the shaft 2657. The angled surfaces 2613 extend helically around the shaft 2657.

[0155]

[0220] The take-up hub 2652 is axially constrained to the base 2654 via a bayonet connection 2649 between the shaft 2657 and the take-up hub 2652. Although the bayonet connection 2649 is described and illustrated as being implemented in a tensioning mechanism 2651 that operates similarly to tensioning mechanism 151A, the bayonet connection 2649 may be similarly implemented in any of the tensioning mechanism embodiments described herein.

[0156]

[0221] 26A and 26B, the bayonet connection 2649 is attached to or integrally formed with the shaft 2657 and thus includes a male bayonet feature or radial extension 2667 attached to the base 2654. The radial extension 2667 is a protrusion extending radially outward from the outer surface of the shaft 2657. The bayonet connection 2649 also includes a female bayonet feature 2669 formed in the take-up hub 2652. The female bayonet feature 2669 includes an internal flange 2671 formed in the inner surface of the take-up hub 2652, the internal flange 2671 having an axial slot 2675 formed therethrough. In the depicted embodiment, a single male bayonet feature and a single female bayonet feature are used, although a greater number may be used. The internal flange 2671 is a planar protrusion that extends radially inward from the inner surface of the take-up hub 2652 to form an internal ledge or shelf. In one embodiment, the internal flange 2671 extends around the entire inner diameter of the take-up hub 2652, except for the width of the axial slot 2675. The axial slot 2675 is configured to allow the radial extension 2667 to pass through the axial slot 2675. During assembly of the tensioning mechanism 2651, the radial extension 2667 and the axial slot 2675 are circumferentially or rotationally positioned when the take-up hub 2652 is axially assembled or mated with the base 2654 such that the radial extension 2667 passes through the axial slot 2675. During assembly of the tensioning mechanism 2651, the bayonet connection 2649 is in an open or unlocked state.

[0157]

[0222] More specifically, the open or unlocked state of the bayonet connection 2649 is shown in FIGS. 26C and 26CC. FIG. 26C illustrates a top view of the tensioning mechanism 2651 in the open or unlocked state, and FIG. 26CC is a cross-sectional view of FIG. 26C. The radial extension 2667 and the axial slot 2675 are circumferentially or rotationally disposed, as best shown in FIG. 26C. Because the radial extension 2667 is disposed through the axial slot 2675 in the flange 2671, the radial extension 2667 does not abut or contact the inner flange 2671. In the open or unlocked state, the take-up hub 2652 is not axially constrained relative to the base 2654. In other words, in the absence of applied force, the compression spring 2658 acts to urge the take-up hub 2652 axially away from the base 2654 when the bayonet connection 2649 is in an open or unlocked state.

[0158]

[0223] The take-up hub 2652 is configured to rotate an amount relative to the base 2654 to axially lock the take-up hub 2652 and the base 2654 together to resist the compression spring load of the compression spring 2658. The closed or locked state of the bayonet connection 2649 is shown in FIGS. 26D and 26DD after the take-up hub 2652 has rotated an amount relative to the base 2654 to axially lock the take-up hub 2652 and the base 2654 together. FIG. 26D illustrates a top view of the tensioning mechanism 2651 in the closed or locked state, and FIG. 26DD is a cross-sectional view of FIG. 26D. The radial extensions 2667 and the axial slots 2675 are no longer circumferentially or rotationally aligned, as best shown in FIG. 26D. The radial extension 2667 abuts against the upper surface of an internal flange 2671, as best seen in FIG. 26DD. The compression spring 2658 presses against the take-up hub 2652, but the internal flange 2671 acts as an axial stop, preventing axial movement of the take-up hub 2652, so that the take-up hub 2652 is axially constrained relative to the base 2654 in the closed or locked state. In the closed or locked state, the tensioning mechanism 2651 is a stable subassembly that can be installed in an inhalation device. In the embodiment of FIGS. 26A-26N, the take-up hub 2652 is configured to rotate approximately ninety degrees (90°) relative to the base 2654 to transition the bayonet connection 2649 from an open or unlocked state to a closed or locked state. However, this is by way of example only, and other amounts of relative rotation may be utilized. For example, the rotation for locking may be less than ninety degrees (90°) as long as the bayonet features properly engage, or may be more than ninety degrees (90°) as long as there is sufficient space for subsequent rotation of the take-up hub 2652 during operation.

[0159]

[0224] As the take-up hub 2652 rotates to transition the bayonet connection 2649 from an open or unlocked state to a closed or locked state, the nut 2656 also rotates because the nut 2656 is engaged with the take-up hub 2652 and rotates with the take-up hub 2652. More specifically, the nut 2656 is described in more detail with reference to FIG. 26E, and the take-up hub 2652 is described in more detail with reference to FIG. 26F. FIG. 26E is a perspective view of the nut 2656 removed from the tensioning mechanism 2651 for illustrative purposes only. The nut 2656 is disposed between the take-up hub 2652 and the base 2654 and is coupled to each of the take-up hub 2652 and the base 2654. The nut 2656 is coupled to the take-up hub 2652 via a splined connection (similar to splined connection 159A) such that the take-up hub 2652 rotates with the nut 2656 and relative rotation therebetween is not permitted. Stated another way, due to the splined connection, the take-up hub 2652 is rotationally locked to the nut 2656 such that the nut 2656 and the take-up hub 2652 rotate as an assembly. The nut 2656 operates similarly to the nut 156A described herein, but has a different structure. In this embodiment, the splined connection includes a plurality of outwardly extending ribs 2617 that protrude or extend radially outward from the outer circumferential surface of the lower collar portion of the nut 2656, each of which is received in an axial slot 2615 in the take-up hub 2652. The take-up hub 2652 includes a plurality of axial slots 2615 formed in the inner circumferential surface of the take-up hub 2652. Each outwardly extending rib 2617 is allowed to slide or move axially along the axial slot 2615 so that the nut 2656 is allowed to slide or move axially relative to the take-up hub 2652, but the outwardly extending rib 2617 does not allow the nut 2656 to rotate relative to the take-up hub 2652.

[0160]

[0225] Rather than the inwardly extending ribs 119A of nut 156A, nut 2656 includes an upper or cam follower portion disposed axially above a collar portion of nut 2656. This cam follower portion of nut 2656 includes a lower surface 2619 that mates with and corresponds to the helically ramped surface 2613 of cam surface 2655 such that the cam follower portion of nut 2656 is disposed on and engages cam surface 2655 of base 2654.

[0161]

[0226] When the take-up hub 2652 is axially assembled to the base 2654 prior to locking the bayonet connection 2649, the take-up hub 2652 also engages the nut 2656 such that relative rotation therebetween is not permitted. As a result, when the bayonet feature 2649 is locked, the nut 2656 also rotates relative to the base 2654, thereby reducing the amount of rotation or travel available to the nut 2656 during normal operation. Accordingly, FIGS. 26G, 26H, and 261 depict a nesting fixture or tool 2677 that may be temporarily coupled to the base 2654 for initially installing or assembling the nut 2656 to the base 2654 before the take-up hub 2652 is added, such that the nut 2656 is rotated back an amount equal to the locking rotation from the target initial position. As a result, after assembly is complete and the bayonet feature 2649 is locked (thereby rotating the nut 2656), the nut 2656 rotates forward back to the target initial position once the take-up hub 2652 is rotationally locked. When in the target initial position, the nut 2656 is biased fully downward against the base 2654 at the bottom of the cam surface 2655. The use of the nesting fixture 2677 maximizes the degree or amount of rotation of the nut 2656 relative to the base 2654 during normal use.

[0162]

[0227] 26G. The nesting fixture 2677 is configured to hold or retain the nut 2656 at an elevated height relative to the base 2654, and therefore the rotational position required for assembly, when the nut 2656 is urged against the cam surface 2655 of the base 2654. The nesting fixture 2677 includes a plurality of uprights 2679 sized and configured to pass through a plurality of apertures 2683 formed in the base 2654, as shown in FIG. 26H. The inner and outer diameters of the uprights 2679 are configured to permit rotation of the nut 2656 and take-up hub 2652 during locking rotation of the bayonet connection 2649 without interfering with the splined connection 2659 between the nut 2656 and take-up hub 2652. The nesting fixture 2677 also includes a central locating pin 2681 for centering the base 2654 on the nesting fixture 2677 when the base 2654 is disposed on the top surface of the nesting fixture 2677. Figure 261 illustrates the base 2654 disposed on the top surface of the nesting fixture 2677, with the uprights 2679 of the nesting fixture 2677 extending through apertures 2683 in the base 2654.

[0163]

[0228] 26J illustrates a nut 2656 disposed or supported on a plurality of uprights 2679 at a position corresponding to ninety degrees (90°) behind or rearward from a target initial position of the nut 2656. The nut 2656 is rotationally secured by a rotation stop 2685 disposed between one of the uprights 2679 of the nesting fixture 2677 and the nut 2656. The rotation stop 2685 ensures that the nut 2656 does not rotate out of engagement with the cam surface 2655.

[0164]

[0229] 26K, when take-up hub 2652 (which is not shown in FIG. 26K so that nut 2656 can be seen) rotates to lock bayonet feature 2649, nut 2656 rotates with take-up hub 2652 as described above, thereby moving up inclined surface 2613 of cam surface 2655. Nut 2656 moves up and over inclined surface 2613 and its apexes, as indicated by the directional arrows in FIG. 26K, with each apex located at a junction between inclined surface 2613 and vertical surface 2611. As nut 2656 moves over the apexes of cam surface 2655, compression spring 2658 biases nut 2656 back down against uprights 2679 of nested fixture 2677 to a height defined by the uprights. When the tensioning mechanism 2651 is removed from the nesting fixture 2677, the nut 2656 continues to move toward the base 2654 due to the spring force of the compression spring 2658 until it reaches its target initial position (i.e., fully biased downward against the base 2654 at the bottom of the cam surface 2655).

[0165]

[0230] Referring to FIG. 26L , another feature of tensioning mechanism 2651 is illustrated. More specifically, as a secondary means of alerting the user to the dose counter, tensioning mechanism 2651 is configured to output an audible click to alert the user of the inhaler that the device has been used (i.e., all doses on the blister strip(s) have been delivered). As the inhaler is operated to sequentially deliver doses, nut 2656 moves up inclined surface 2613 of cam surface 2655. At the end of the device's life, nut 2656 moves up inclined surface 2613 to rest on its apexes, each apex located at the junction between inclined surface 2613 and vertical surface 2611. If the user continues to operate the inhaler (i.e., via rotation of mouthpiece cover 108) after all doses have been dispensed, nut 2656 will exceed the allotted or allowed amount of rotation and move past the apex of cam surface 2655, as indicated by the directional arrow in FIG. 26L . As the nut 2656 moves over the apex of the cam surface 2655 and drops off the inclined surface 2613, the nut 2656 is urged back down to the base 2654 by the compression spring 2658, producing or outputting an audible click.

[0166]

[0231] 26M and 26N, another feature of the tensioning mechanism 2651 is illustrated. More specifically, the tensioning mechanism 2651 includes a lockout mechanism 2687 configured to prevent disassembly of the bayonet connection 2649 if the user continues to attempt to operate the inhalation device after all doses have been dispensed. In other words, the lockout mechanism 2687 limits how far the take-up hub 2652 can be wound or rotated in order to prevent the male and female bayonet features of the bayonet connection 2649 from realigning and causing the take-up hub 2652 to disassemble axially due to the force of the compression spring 2658 within the take-up hub 2652.

[0167]

[0232] As previously mentioned, the nut 2656 includes a plurality of outwardly extending ribs 2617 that protrude or extend radially outward from the outer periphery of the nut 2656 for engaging the take-up hub 2652. In this embodiment, the outwardly extending ribs 2617 also function as stop features for the lockout mechanism 2687. More specifically, in this embodiment, the nut 2656 includes a total of three outwardly extending ribs 2617 that are equally circumferentially spaced apart, i.e., spaced equidistantly at 120° around the outer periphery of the nut 2656. After all doses have been dispensed and the nut 2656 has moved beyond the apex of the cam surface 2655, the outwardly extending ribs 2617 are disposed on the base 2654 at different positions from where they started, as described above with respect to FIG. 26L . The base 2654 includes a plurality of pockets 2689 configured to receive the outwardly extending ribs 2617 in this end-of-life state. When the outwardly extending ribs 2617 are received in the pockets 2689, any further rotation of the nut 2656 (and thus the take-up hub 2652, which is rotationally locked to the nut 2656) is prevented. While the pockets 2689 are sufficient to receive the outwardly extending ribs 2617 and prevent further rotation of the nut 2656, the lockout mechanism 2687 can include a plurality of raised stop blocks 2691 on the base 2654 adjacent the pockets 2689 to increase vertical engagement with the outwardly extending ribs 2617.

[0168]

[0233] Figure 26M illustrates the starting or initial position of the outwardly extending ribs 2617 at the beginning of the device's life, while Figure 26N illustrates the ending position of the outwardly extending ribs 2617 at the end of the device's life after all doses have been dispensed and the nut 2656 has moved past the apex of the cam surface 2655. In the starting position of Figure 26M, the outwardly extending ribs 2617 of the nut 2656 are initially positioned within the spirally swept clearance grooves 2693 and are permitted to rotate during operation of the inhalation device. The base 2654 includes a total of three clearance grooves 2693 for receiving the three outwardly extending ribs 2617. Each clearance groove 2693 is disposed midway between a pair of adjacent pockets 2689. In the end position of FIG. 26N, the nut 2656 has rotated 180° during operation of the inhaler and has dropped over the cam surface 2655, with the outwardly extending rib 2617 disposed within the pocket 2689 and prevented from further rotation by the stop block 2691 of the lockout mechanism 2687.

[0169]

[0234] The lockout mechanism 2687 preferably includes three equally spaced rotational stop features with a relatively large diameter that maintain the same rotation of the nut 2656 relative to the base 2654 during normal operation. The nut 2656 passes over the cam surface 2655 before the lockout mechanism 2687 is activated, and the audible click described in connection with FIG. 26J signals engagement of the lockout mechanism 2687.

[0170]

[0235] 27A-27D illustrate alternative embodiments of lockout mechanisms that may be integrated into the tensioning mechanism 2651 to prevent disengagement of the bayonet connection 2649. In FIG. 27A, the lockout mechanism 2787A includes a rotational stop or block 2791A disposed on the bayonet connection 2649 at the end of the internal flange 2671. In FIG. 27B, the lockout mechanism 2787B includes a rotational stop or block 2791B disposed on the lower outer periphery of the hub 2652. In FIGS. 27C and 27D, the lockout mechanism 2787C includes a rotational stop or block 2791C disposed on the shaft 2657 at the upper end of the cam surface 2655 and a pair of opposing notches in the upper end of the nut 2656. In this embodiment, the nut includes a first notch 2789A that is relatively larger than a second notch 2789B. 27C, the first cutout 2789A is configured to allow the nut 2656 to move across or drop off the cam surface 2655 during assembly of the tensioning mechanism 2651 when the bayonet connection 2649 is locked. With reference to FIG. 27D, the second cutout 2789B is configured to prevent the nut 2656 from moving across or dropping off the cam surface 2655 at the end of the device's life, thereby preventing further rotation of the nut 2656 relative to the base 2654.

[0171]

[0236] While various embodiments according to the present invention have been described above, it should be understood that they have been presented by way of illustration and example only, and not by way of limitation. It will be apparent to those skilled in the art that various changes in form and detail can be made therein without departing from the spirit and scope of the invention. Accordingly, the breadth and scope of the present invention should not be limited by any of the exemplary embodiments described above, but should be defined only in accordance with the appended claims and their equivalents. It will also be understood that each feature of each embodiment discussed herein and each reference cited herein can be used in combination with the features of any other embodiment. All patents and publications discussed herein are incorporated herein by reference in their entirety.

Claims

1. 1. A tensioning mechanism for peeling a sheet from a blister strip for use in a dry powder inhaler device, comprising: A base and a nut including at least one rib that engages the cam surface; a compression spring longitudinally adjacent to the nut; a take-up hub disposed around the nut and the compression spring, the nut being disposed between the take-up hub and the base and coupled to each of the take-up hub and the base, the take-up hub rotationally constrained to the nut; Equipped with the winding hub is configured to rotate relative to the base; the nut is configured to interact with the compression spring and the cam surface to apply a torque to the take-up hub when the base is driven in rotation; A tensioning mechanism whereby when the take-up hub applies an opposing torque to the nut, the nut moves along the cam surface and axially compresses the compression spring.

2. 2. The tensioning mechanism of claim 1, wherein the take-up hub includes a hook on an outer surface of the take-up hub, the hook configured to be attached to an end of the sheet of blister strip such that rotation of the take-up hub causes the sheet of blister strip to wrap around the take-up hub.

3. The tensioning mechanism of claim 1 , wherein the take-up hub is axially constrained relative to the base.

4. 4. The tensioning mechanism of claim 3, wherein the take-up hub is axially constrained to the base via a bayonet connection between the base and the take-up hub.

5. 5. The tensioning mechanism of claim 4, wherein the bayonet connection includes a radial extension of the base and an internal flange of the winding hub, the internal flange including an axial slot configured to allow passage of the radial extension.

6. The tensioning mechanism of claim 1 , wherein the base includes a plurality of gear teeth integrally formed with or secured to an outer periphery of the base.

7. The tensioning mechanism of claim 1 , wherein the cam surface includes alternating vertical and angled surfaces.

8. The tensioning mechanism of claim 7 , wherein the at least one rib comprises a plurality of circumferentially spaced ribs.

9. 2. The tensioning mechanism of claim 1, wherein the cam surface is integrally formed with or fixed to a portion of the base, the at least one rib projects radially inward from an inner peripheral surface of the nut, and the take-up hub is rotationally locked to the nut.

10. The tensioning mechanism of claim 9 , wherein the compression spring extends between the take-up hub and the nut.

11. 10. The tensioning mechanism of claim 9, wherein the take-up hub is rotationally locked to the nut via an outwardly extending rib that projects radially outward from an outer periphery of the nut and is received in an axial slot in the take-up hub.

12. 10. The tensioning mechanism of claim 9, wherein the cam surface has a first outer diameter and the compression spring has a second outer diameter, the first outer diameter being greater than the second outer diameter.

13. 2. The tensioning mechanism of claim 1, wherein the cam surface is integrally formed with or fixed to a portion of the take-up hub, the at least one rib projects radially outward from an outer peripheral surface of the nut, and the base is rotationally locked to the nut.

14. 14. The tensioning mechanism of claim 13, wherein a shaft extends from the base, the shaft being integrally formed with or fixed to the base, the base being rotationally locked to the nut via an inwardly extending rib projecting radially inward from an inner periphery of the nut and received in an axial slot in the shaft.

15. The tensioning mechanism of claim 1 , wherein the compression spring extends between the nut and the base.

16. 1. A dry powder inhaler device comprising: a housing for receiving at least one blister strip for use in the dry powder inhaler device, the blister strip including a bottom sheet and a top sheet releasably secured to the bottom sheet; The tensioning mechanism of claim 1 disposed within the housing; an indexing spool driven to rotate in a first direction, the outer surface of the indexing spool receiving the bottom sheet of the blister strip; Equipped with an outer surface of the take-up hub is attached to an end of the top sheet, and a second, opposite rotation of the take-up hub causes the top sheet to wrap around the outer surface of the take-up hub; an increase in tension along the top sheet of the blister strip causes rotation of the winding hub relative to the base in the first direction to reduce tension along the top sheet of the blister strip; A dry powder inhaler, wherein the axial compressive force of the compression spring is transmitted to a torque applied to the take-up hub.

17. 1. A dry powder inhaler device comprising: a housing for receiving at least one blister strip for use in the dry powder inhaler device, the blister strip including a bottom sheet and a top sheet releasably secured to the bottom sheet; an indexing spool driven to rotate in a first direction, the outer surface of the indexing spool receiving the bottom sheet of the blister strip; a winding hub that is driven to rotate in either the first direction or a second opposite direction, the outer surface of the winding hub being attached to an end of the top sheet, and rotation of the winding hub causes the top sheet to wrap around the outer surface of the winding hub; a tensioning mechanism including a slider and at least one spring attached to the slider, the tensioning mechanism coupled to the housing to permit axial movement of the slider relative to the housing along a predetermined path; Equipped with the slider is configured to receive an intermediate portion of the top sheet of the blister strip, the intermediate portion of the top sheet being disposed between the index spool and the take-up hub; A dry powder inhaler device wherein an increase in tension along the top sheet of the blister strip results in axial movement of the slider along the predetermined path, and axial movement of the slider axially compresses or expands the spring to reduce the tension along the top sheet of the blister strip.

18. 18. The dry powder inhaler of claim 17, wherein a first end of the spring is attached to the slider and a second end of the spring is attached to the housing.

19. 18. The dry powder inhaler of claim 17, wherein the predetermined path is defined by a recess in the interior surface of the housing.

20. 18. The dry powder inhaler of claim 17, wherein the spring is a compression spring that biases the slider away from each of the indexing spool and the take-up hub.

21. 21. The dry powder inhaler of claim 20, wherein axial compression of the compression spring urges the slider toward each of the indexing spool and the take-up hub.

22. 18. The dry powder inhaler of claim 17, wherein the predetermined path is linear.

23. 20. The dry powder inhaler of claim 17, wherein the at least one spring comprises a single spring.

24. 20. The dry powder inhaler of claim 17, wherein the at least one spring comprises two springs.

25. 18. The dry powder inhaler of claim 17, wherein the take-up hub is rotationally driven in the first direction.

26. 18. The dry powder inhaler of claim 17, wherein the take-up hub is rotationally driven in the second opposite direction.

27. 18. The dry powder inhaler of claim 17, wherein the at least one spring is a compression spring, and axial movement of the slider causes the spring to compress axially, reducing the tension along the top sheet of the blister strip.

28. 18. The dry powder inhaler of claim 17, wherein the at least one spring is a tension spring, and axial movement of the slider causes the spring to stretch axially, reducing the tension along the top sheet of the blister strip.

29. 1. A dry powder inhaler device comprising: a housing for receiving at least one blister strip for use in the dry powder inhaler device, the blister strip including a bottom sheet and a top sheet releasably secured to the bottom sheet, the housing including a curved slot in an inner surface of the housing and a pin extending radially from the inner surface of the housing, the pin disposed adjacent a first end of the curved slot and secured to the housing; an indexing spool driven to rotate in a first direction, the outer surface of the indexing spool receiving the bottom sheet of the blister strip; a second, oppositely rotationally driven take-up hub, the outer surface of the take-up hub being attached to an end of the top sheet, the take-up hub being coupled to the housing such that rotation of the take-up hub causes the top sheet to wrap around the outer surface of the take-up hub, and the take-up hub is coupled to the housing such that movement of the take-up hub relative to the housing along the curved slot; a tensioning mechanism including at least one spring coupled to the take-up hub, a first end of the spring being fixed to the housing and a second end of the spring being coupled to the take-up hub; Equipped with the pin is configured to receive an intermediate portion of the top sheet of the blister strip, the intermediate portion of the top sheet extending between the index spool and the take-up hub; A dry powder inhaler device, wherein an increase in tension along the top sheet of the blister strip causes the take-up hub to move along the curved slot in the housing, and the movement of the take-up hub axially deforms the spring, reducing the tension along the top sheet of the blister strip.

30. 30. The dry powder inhaler of claim 29, wherein the at least one spring is a tension spring.

31. 30. The dry powder inhaler of claim 29, wherein the tensioning mechanism includes a bracket having a first end coupled to allow relative rotation of the indexing spool with respect to the bracket, a second end attached to the second end of the spring, and an intermediate portion coupled to the take-up hub to allow relative rotation of the take-up hub with respect to the bracket.

32. 32. The dry powder inhaler of claim 31, wherein the bracket is permitted to rotate relative to the housing.

33. 33. The dry powder inhaler of claim 32, wherein the spring is biased to position the take-up hub at the first end of the curved slot and at a second end of the curved slot opposite the pin, and movement of the take-up hub toward the pin stretches the tension spring axially, reducing the tension along the top sheet of the blister strip.

34. 30. The dry powder inhaler of claim 29, wherein the spring is aligned with the centerline of the top sheet.

35. 30. The dry powder inhaler of claim 29, wherein the curved slot is concentric with the axis of rotation of the indexing spool.

36. 30. The dry powder inhaler of claim 29, wherein the at least one spring is a torsion spring.

37. 37. The dry powder inhaler of claim 36, wherein the at least one spring includes a first torsion spring and a second torsion spring, the first torsion spring configured to act on a first side of the take-up hub and the second torsion spring configured to act on a second, opposite side of the take-up hub.

38. 37. The dry powder inhaler of claim 36, wherein a first leg of the torsion spring is fixed to the inner surface of the housing, and a second leg of the torsion spring is coupled to the take-up hub for movement along the curved slot in conjunction with the take-up hub.

39. 39. The dry powder inhaler of claim 38, wherein the body of the torsion spring is disposed concentrically with the axis of rotation of the indexing spool.

40. 39. The dry powder inhaler of claim 38, wherein the torsion spring is biased to position the take-up hub at a first end of the curved slot and at a second end of the curved slot opposite the pin, and movement of the take-up hub toward the pin twists the torsion spring to reduce tension along the top sheet of the blister strip.

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