Development of inhalation technology for drug delivery has contributed immensely in treating various intrapulmonary and extrapulmonary diseases. This is supported by the unique geometry of the lungs such as a large surface area, thin alveolar epithelial lining, high vascularization, and avoidance of first-pass metabolism. Numerous inhalation delivery systems have been developed and studied to treat lung diseases such as asthma, chronic obstructive pulmonary disease (COPD), and other pulmonary infections. Among them, three approaches, that is, nebulizers, pressurized metered-dose inhalers (pMDIs), and dry powder inhalers (DPI), are extensively scrutinized for the treatment of several lung diseases and pathological conditions. Utilization of nebulizers requires bulky compressors or a source of compressed air, while pMDIs have limitations such as sedimentation, crystal growth, and selection of appropriate propellant and they emit dosages at high velocity, which build deposition in the oropharynx, most commonly where they are swallowed and enhance the risk of systemic absorption. DPIs were introduced to cure some of the weaknesses associated with nebulizers and pMDIs.
A wide variety of devices are known for dispensing doses of medicament in the form of powder for inhalation. Devices are known which contain a store of powdered medicament from which individual doses are metered as required. Devices are also known which include carriers having a plurality of pockets containing respective doses of powder. These carriers are typically in the form of blister-packs. All of these devices face problems of providing reliable, repeatable and accurate inhaled amounts of powder.
There are problems in ensuring that all of a dispensed dose of powder is entrained into the airstream for inhalation. There are other problems in providing repeatable and consistent release of powder into the inhalation airstream as desired, problems with over or under delivery of medication. For example, when an inhaling device is misused by not actuating the lever fully or by not conforming with other instructions for use, the counters may decrement prior to a dose having been made available to the user and the user may be missing needed medication. These mistakes can be repeated for multiple actuations.
Therefore, it would be beneficial to provide an inhaling device that incorporates a design feature that would minimize the incidence of counter miscounting and/or misindexing.
The present application provides a priming member for an inhaler. The priming member comprises a cantilever blade configured to engage a chassis of the inhaler. The cantilever blade has a proximal portion, a body and a distal portion, the body being disposed between the proximal portion and the distal portion of the cantilever blade. The cantilever blade has a flexible portion extending with the proximal portion of the cantilever blade to allow movement of the cantilever blade relative to the priming member. The flexible portion of the cantilever blade is a hinge flexure allowing the cantilever blade to move in an upward and downward direction relative to the chassis of the inhaling device.
The cantilever blade is adapted to pass over a shelf of the chassis upon actuation of the inhaler and under the shelf of the chassis upon indexing of the inhaling device. The body of the cantilever blade comprises a longitudinal axis extending from the proximal portion to the distal portion of the cantilever blade, and the flexible portion extends transverse to the longitudinal axis following a transverse axis. The cantilever blade also comprises a first surface and a second surface extending along the longitudinal axis of the cantilever blade, the first surface opposite the second surface such that a first gap is formed between the priming member and the first surface of the cantilever blade and a second gap is formed between the second surface and the priming member. The distal end of the cantilever blade comprises an angled tip, which, in some aspects, can be chamfered. In some aspects, the cantilever blade has a wedge shape or a rectangular shape.
This application also provides an inhaler for inhaling a dose of powder. The inhaler includes a mouthpiece for inhaling the dose of powder and a priming member including a cantilever blade configured to engage a chassis of the inhaler. The cantilever blade of the priming member has a proximal portion, a body and a distal portion, the body being disposed between the proximal portion and the distal portion of the cantilever blade and the cantilever blade having a flexible portion extending with the proximal portion of the cantilever blade to allow movement of the cantilever blade relative to the priming member fluidly coupled to the mouthpiece.
A chassis for an inhaler is also provided. The chassis comprises a plate having guide members disposed adjacent a first aperture, a pivot shaft configured for supporting a priming member, a peripheral casing configured for rotatably supporting a pocket having a medicament, a clip having a second aperture for receiving a wheel rotatably mounted on the chassis on an axis offset from a central axis, and a shelf disposed adjacent the second aperture, the shelf defining a third aperture, the third aperture configured for receiving a cantilever blade of the priming member of the inhaler. The chassis further comprises a plurality of radially located ribs on the chassis and a plurality of peripherally located buttresses on the chassis configured for stabilizing the chassis and the priming member of the inhaler. In some embodiments, the third aperture is enclosed by a wall at one end and by an edge support at the other end. In other embodiments, the chassis further comprises a lower step and a higher step, the steps peripherally positioned on the chassis to allow molding.
In various embodiments, an inhaler is provided, the inhaler comprising a chassis having abutment members and a hollow pivot, a dispensing mechanism and an indexing mechanism, the chassis supporting the dispensing mechanism and the indexing mechanism, the dispensing mechanism comprising a priming member which comprises a priming lever, a first prodger and a second prodger mounted on the priming member, a central cam moveable as part of the indexing mechanism, a pivot opening adapted to be rotatably supported by the hollow pivot of the chassis, a driving member and a rib, the rib joining the central cam to the driving member; and the indexing mechanism comprises a Geneva wheel rotatably mounted on the chassis on an axis offset from a central axis. In some applications, the driving member further comprises a rigid cantilever blade affixed to the priming member by a hinge flexure, the cantilever blade adapted to pass over the shelf of the chassis upon actuation of the inhaling device and under the shelf upon indexing of the inhaling device. In other applications, the first prodger and second prodger are moveable towards and away from a second side surface of a supported first and second carriers of an inhaling device between a retracted and an extended position.
In various embodiments, the priming member further comprises an elongated cam member extending from the central cam towards a recess disposed opposite the leading portion of the driving member of the priming member, a lateral cam surface and at least an elongated opening, the at least an elongate opening of the priming member and the shelf of the chassis being arranged so to hold the prodgers rotationally to allow them to move towards and away from the supported first and second carriers by means of the central cam and the lateral cam surface. The Geneva wheel includes a peg wheel and two gears coaxial with the peg wheel, the peg wheel adapted to cooperate with the priming member. In many aspects, the indexing mechanism is arranged for moving a first support and a second support relative to the first and second prodgers so as to selectively align the pockets of the carriers with the respective prodgers.
In various aspects, when the priming lever begins an actuation stroke, if the priming lever is not pushed to the end of the stroke, the priming lever will return on the top of the shelf without indexing the dose carrier or the counter and the counter temporarily shows one index behind the number of doses taken. In other aspects, when the priming lever drops off the end of the shelf of the chassis at the end of an actuation stroke, the priming lever passes under the shelf of the chassis to engage the Geneva wheel advancing the dose carrier and decrementing the counter and the counter correctly represents the number of doses taken.
In some embodiments, a method of treating a respiratory disease is provided. The method of treatment comprises inhaling a powder for treating the respiratory disease from an inhaler, the inhaler comprising a mouthpiece for inhaling the dose of powder and a priming member comprising a cantilever blade configured to engage a chassis of the inhaler, the priming member having a proximal portion, a tapered body and a distal portion, the tapered body being disposed between the proximal portion and the distal portion of the cantilever blade and the cantilever blade having a flexible portion extending with the proximal portion of the cantilever blade to allow movement of the cantilever blade relative to the priming member fluidly coupled to the mouthpiece.
In other aspects, a method of treating a respiratory disease is provided. This method of treatment comprises inhaling a powder for treating the respiratory disease from an inhaler, the inhaler comprising a chassis having abutment members and a hollow pivot, a dispensing mechanism and an indexing mechanism, the chassis supporting the dispensing mechanism and the indexing mechanism; the dispensing mechanism comprising a priming member which comprises a priming lever, a first prodger and a second prodger mounted on the priming member, a central cam moveable as part of the indexing mechanism, a pivot opening adapted to be rotatably supported by the hollow pivot of the chassis, a driving member and a rib, the rib joining the central cam to the driving member; and the indexing mechanism comprises a Geneva wheel rotatably mounted on the chassis on an axis offset from a central axis. The driving member utilized in this method further comprises a rigid cantilever blade affixed to the priming member by a hinge flexure, the cantilever blade adapted to pass over the shelf of the chassis upon actuation of the inhaling device and under the shelf upon indexing of the inhaling device.
In other embodiments, a method of loading an inhaler is provided. The method of loading the inhaler includes inserting a carrier into the inhaler, the carrier comprising a plurality of pockets, each of the plurality of pockets containing individual doses of powder for inhalation, the inhaler comprising a mouthpiece for inhaling the dose of powder; and a priming member comprising a cantilever blade configured to engage a chassis of the inhaler, the priming member having a proximal portion, a tapered body and a distal portion, the tapered body being disposed between the proximal portion and the distal portion of the cantilever blade and the cantilever blade having a flexible portion extending with the proximal portion of the cantilever blade to allow movement of the cantilever blade relative to the priming member fluidly coupled to the mouthpiece. In some aspects, the method of loading an inhaler includes inserting a carrier into the inhaler, the carrier comprising a plurality of pockets, each of the plurality of pockets containing individual doses of powder for inhalation, the inhaler comprising a chassis having abutment members and a hollow pivot, a dispensing mechanism and an indexing mechanism, the chassis comprising a shelf and supporting the dispensing mechanism and the indexing mechanism; the dispensing mechanism comprising a priming member which comprises a priming lever, a first prodger and a second prodger mounted on the priming member, a central cam moveable as part of the indexing mechanism, a pivot opening adapted to be rotatably supported by the hollow pivot of the chassis, a driving member and a rib, the rib joining the central cam to the driving member; and the indexing mechanism comprises a Geneva wheel rotatably mounted on the chassis on an axis offset from a central axis. In other aspects, the driving member of the priming member further comprising a rigid cantilever blade affixed to the priming member by a hinge flexure, the cantilever blade adapted to pass over the shelf of the chassis upon actuation of the inhaling device and under the shelf upon indexing of the inhaling device.
Other features and advantages of the present disclosure will become apparent from the following detailed description. It should be understood, however, that the detailed description and the specific examples, while indicating several embodiments of the disclosure, are given by way of illustration only, since various changes and modifications within the spirit and scope of the disclosure will become apparent to those skilled in the art from this detailed description.
In part, other aspects, features, benefits and advantages of the embodiments will be apparent with regard to the following description, appended claims, and accompanying drawings.
Further, the relation between objects in a figure may not be to scale, and may in fact have a reverse relationship as to size. The figures are intended to bring understanding and clarity to the structure of each object shown, and thus, some features may be exaggerated in order to illustrate a specific feature of a structure.
The present disclosure may be understood more readily by reference to the following detailed description of the disclosure presented in connection with the accompanying drawings, which together form a part of this disclosure. It is to be understood that this disclosure is not limited to the specific devices, methods, conditions or parameters described and/or shown herein, and that the terminology used herein is for the purpose of describing particular embodiments by way of example only and is not intended to be limiting of the claimed disclosure. The following description is presented to enable any person skilled in the art to make and use the present disclosure.
Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the application are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements. Moreover, all ranges disclosed herein are to be understood to encompass any and all subranges subsumed therein. For example, a range of “1 to 10” includes any and all subranges between (and including) the minimum value of 1 and the maximum value of 10, that is, any and all subranges having a minimum value of equal to or greater than 1 and a maximum value of equal to or less than 10, e.g., 5.5 to 10.
As used in the specification and including the appended claims, the singular forms “a,” “an,” and “the” include the plural, and reference to a particular numerical value includes at least that particular value, unless the context clearly dictates otherwise.
Ranges may be expressed herein as from “about” or “approximately” one particular value and/or to “about” or “approximately” another particular value. When such a range is expressed, another embodiment includes from the one particular value and/or to the other particular value.
Spatially relative terms such as “under”, “below”, “lower”, “over”, “upper”, and the like, are used for ease of description to explain the positioning of one element relative to a second element. These terms are intended to encompass different orientations of the device in addition to different orientations than those depicted in the figures. Further, terms such as “first”, “second”, or the like, are also used to describe various elements, regions, sections, etc. and are also not intended to be limiting. Like terms refer to like elements throughout the description.
As used herein, the terms “having”, “containing”, “including”, “comprising” and the like are open ended terms that indicate the presence of stated elements or features, but do not preclude additional elements or features.
The term “medicament” includes a substance suitable for oral or nasal inhalation. The medicament can include an active pharmaceutical ingredient and an excipient.
The term “dry powder inhaler” (DPI), refers to a device that delivers medication to the lungs in the form of a dry powder. DPIs are commonly used to treat respiratory diseases such as asthma, bronchitis, emphysema and COPD. DPIs can be divided into three basic types: i) bulk powder dispensers which hold enough bulk powder for a plurality of doses; ii) single dose dispensers, for the administration of a single dose of the active compound; and iii) multiple-dose inhalers pre-loaded with quantities of active principles sufficient for longer treatment cycles.
The term “metered-dose inhaler” (MDI) refers to a device that delivers a specific amount of medication to the lungs, in the form of a short burst of aerosolized medicine that is usually self-administered by the patient via inhalation. MDIs are commonly used as delivery systems for treating asthma, chronic obstructive pulmonary disease (COPD) and other respiratory diseases.
The term “container” refers to a receptacle for a medicament. In some embodiments, the container can have one or more pockets for the medicament.
The term “unit dose”, “unit dose receptacle”, and/or “dose unit” refers to a container comprising a pocket(s) that contains a medicament configured to be dispensed to a patient at a particular dose.
The headings below are not meant to limit the disclosure in any way; embodiments under any one heading may be used in conjunction with embodiments under any other heading.
Reference will now be made in detail to certain embodiments of the application, examples of which are illustrated in the accompanying figures. While the application will be described in conjunction with the illustrated embodiments, it will be understood that they are not intended to limit the application to those embodiments.
The present application provides an inhalation device from which a user may inhale consecutive doses of medicament in the form of dry powder. An embodiment is illustrated in
In order to use the device, mouthpiece cover 4 is rotated away from housing 2. As illustrated in
As illustrated in
It should be noted that locating the first position of priming lever 8 adjacent mouthpiece 6 is highly advantageous, since it discourages a user from attempting to inhale from mouthpiece 6 before moving priming lever 8 away from mouthpiece 6 to the second position of
After use of the device, mouthpiece cover 4 may be rotated back to its stowed position illustrated in
As illustrated in
Many aspects of the present application are applicable to devices housing a wide variety of different dose carriers. In particular, many of the features of the embodiment described below can be used with carriers having a traditional blister-pack construction, with carriers having various arrays of pockets and, in some arrangements, with some carriers having a single respective pocket. Nevertheless, the present application is useful when used with carriers of the form illustrated in
As illustrated in
As illustrated in
As illustrated by the cross-sections of
By pushing on the closed end of insert 26 from the side of second lidding sheet 24, it is possible to push insert outwardly from base 14 of carrier 12 through first lidding sheet 22. This is illustrated in
Within housing 2 of the inhalation device, in one embodiment, two of the carriers 12 are arranged coaxially side by side as illustrated in
As illustrated, priming lever 8 is positioned such that it extends between carriers 12 and is rotatable about the common axis of carriers 12 so as to operate a dispensing mechanism and an indexing mechanism.
In an embodiment, each support 30 is made up of two components, namely an anvil plate 32 and an airway plate 34. These are illustrated in
Each anvil plate 32 has a planar surface 36 which, in use, abuts against the first side surface 16 of associated carrier 12 as covered by first lidding sheet 22. Each anvil plate 32 also includes a plurality of guide through holes 38 corresponding to through holes 20 of associated carrier 12.
In this way, as illustrated schematically in
As illustrated by the cross-section of
As illustrated in
As illustrated in
As illustrated in
As illustrated in
In this way, when a user inhales through the device and creates an airstream through it, the airstream drawn through inlet 42 will be directed down into any powder in insert 26 so as to dislodge it and move it into the airstream so as to be carried out of outlet 44. In the illustrated embodiment, recessed channel 46, which connects the volume of the pocket to outlet 44, is positioned adjacent inlet 42. In this way, the airstream from inlet 42 is deflected from the base of insert 26 (and any powder there) so as to travel back towards recessed channel 46. Powder carried in the airstream up into recessed channel 46 is subjected to a relatively sharp change in direction. As a result of this, powder in the airstream tends to be disaggregated. Furthermore, the powder will tend to hit the surfaces of recessed channel 46 also contributing to disaggregation.
As is clear from
As illustrated in
The air velocity is highest where the cross sectional area is smallest so this arrangement provides high velocity air to extract the powder from the pocket and uses the high velocity of the bypass air joining the powder contained in the pocket airflow to assist disaggregation and to protect the walls from powder deposition.
The airflow velocity through the pocket is controlled mainly by the suction pressure created as the user inhales, whereas the volume flow rate is a factor of both velocity and area.
A sufficiently high air velocity should be generated to ensure that the powder is entrained in the airflow. However, if the velocity and flow volume are too high, then there is the possibility that the whole of the mass of powder in the pocket is pushed through the airway as an agglomerated clump. If this happens, the clump may not accelerate to a sufficient velocity for its impact with the walls in the airway to break it up and provide disaggregation. It is believed that the powder is removed gradually from the pocket by the airflow. To achieve this, a small gap 46a is provided between the surface of the powder in the pocket and the airway roof formed from the division in the airway plate 34 between the inlet 42 and recessed channel 46. This, combined with a dimension for “A” that limits the flow volume through the pocket, ensures that the powder is eroded from the pocket rather than pushed out.
To enable this, the inlet hole diameter “a” is chosen to be between 0.5 mm and 2.0 mm for pockets of around 2.0 mm width (in a circumferential direction) and of around 7.3 mm length (in a radial direction). The value chosen depends on the properties of the powder.
In this way, the powder can be removed from the pocket over a time period ranging from between 0.1 s to 1.0 s. This is within the period of the high flow rate of the inhalation cycle and provides good disaggregation of the powder.
It should be appreciated that, in other embodiments, it is possible for parts of the flow path through the pocket, other than the inlet hole, for instance downstream of the powder, to form the minimum cross-sectional area of that flow path. Similar considerations will still apply for the diameter “a” of the inlet hole.
The arrangement of inlet hole 42 and channel 46 is particularly advantageous in conjunction with deep narrow pockets of powder. At a particular flow rate, for instance 10 ltr/min, the surface of the powder will be eroded by a certain depth. Increasing the flow rate to, for instance 20 ltr/min, will result in the powder being eroded by a further depth. Since inhalation by users results in flow rates which increase progressively to a maximum, powder is eroded depth by depth and the pocket is emptied gradually over an appropriate period.
Although the volume and strength of inhalation will vary between users, it is important that the device should not provide too much in the way of resistance to inhalation. In this respect, it would be extremely difficult to inhale through an inlet 42 having a desired cross sectional area. Indeed, where possible, it would result in a flow velocity which was far too high and which would entrain of all of the powder from insert 26 far too quickly. In practice, it is found that approximately only 20% of inhaled air can be used directly for picking up and disaggregating the powder.
As illustrated in
In this way, it is relatively easy to inhale through the device, since a large proportion of the airflow will be through the second flow path. Nevertheless, some of the flow will occur through the first flow path so as to entrain and disaggregate the powder as described above.
In one embodiment, there is another second flow path for the other side of the device and its corresponding carrier. In use, a patient inhales through both second flow paths while drawing powder from the first flow path. Each of the second flow paths is expected to carry approximately 40% of the total inhaled air.
Actual requirements will vary depending upon the nature of the powder and the intended user. For an easily dispensed powder, the portion forming the inlet to the pocket can be small and, for a child or patient with COPD (Chronic Obstructive Pulmonary Disease), the total pressure drop should be low. In this case, an inlet portion could be provided with a cross-sectional area of 2 mm2 and a bypass second flow path with a minimum cross-sectional area of 8 mm2, resulting in a ratio of 25%). On the other hand, with sticky powder for a healthy adult, the inlet portion could be provided with a cross-sectional area of 4 mm2 together with a bypass second flow path having a minimum cross-sectional area of 6 mm2, resulting in a ratio of 66%. Of course, intermediate values are also possible and a useful arrangement has an inlet portion of approximately 3 mm2 with a second flow path minimum cross-sectional area of 6 mm2, resulting in a ratio of 50%.
As illustrated in
As mentioned above with reference to
In some embodiments, the device is arranged such that an inlet passage that provides the air for the flow through the pocket and through the bypass is arranged so that it feeds the air only to the pocket positioned for dispensing, such as illustrated in
This arrangement ensures that, even if none of the powder from a pocket is removed after it has been opened, once it has been indexed on, then the powder will be permanently retained within the device such that it will not be inhaled along with a subsequent dose.
Supports 30 and associated carriers 12 may be rotatably mounted within housing 2 by means of a chassis assembly 58 as illustrated in
As illustrated in
With reference to
Priming member 60 includes an elongate cam member 72 which extends in a circumferential direction and has a cam surface 74 on each of two opposite sides.
Each cam surface 74 interacts with a respective member 76 which will be described as a prodger.
As can be seen in
Referring to
Using carriers of this type, it is possible to position one carrier 12 with the blank portion 82 opposite a prodger 76 while consecutively indexing the other carrier 12 around each of its through holes 20 and the pockets they form until all have been emptied. The indexing mechanism can then rotate the empty carrier to a position in which its blank portion 82 is opposite prodger 76 and rotate the other carrier 12 around all of the positions in which corresponding prodger 76 aligns with through holes 20. In this way, the same dispensing mechanism is used for dispensing powder from both carriers and using the same operation.
Although it is the intention that substantially all of the powder dispensed from the individual pockets will be removed from the device by way of inhalation, it is possible that some powder will remain within the device. Indeed, where different types of carrier are used or the device has a different application, it might be that more powder does remain within the device.
As illustrated in
The actuating mechanism 52, illustrated in detail on
In particular, actuating mechanism 52 comprises a dispensing mechanism adapted to expose each unitary dose 28 to the corresponding flow path, and an indexing mechanism adapted to place each flow path in communication with mouthpiece 6.
Actuating mechanism 52 comprises a disk-shaped chassis 66 which supports the dispensing mechanism and the indexing mechanism. The chassis is fixed to casing 2 and comprises a hollow pivot shaft 64 fitted on shaft 68 of casing 2. At a location, the chassis comprises guide members 71, extending axially and defining a radial aperture between them. Chassis 66 is also provided with a radial extension 70 which interacts with an inner portion of housing 2 so as to rotationally fix chassis 66.
Actuating mechanism 52 further comprises a priming member 60 bearing the priming lever 8 and rotatable about the central axis A so as to operate the dispensing mechanism and the indexing mechanism when the priming lever 8 is actuated.
An example of a suitable priming member 60 is disclosed in WO-A-2005/002644. Priming member 60 is formed of a disk-shaped plate molded in plastic and having a central pivot opening 62 by which it is rotatably supported on pivot shaft 64 of chassis 66.
In the illustrated embodiment, the dispensing mechanism is adapted to move each pocket insert 26 of each carrier 12 from its storage position to its discharge position. Again, an example of a suitable dispensing mechanism, implementing prodgers 76 mounted on the priming member 60, and cam surfaces 74, 73 arranged on priming member 60 and adapted to move prodgers 76 axially, is disclosed in WO-A-2005/002644.
In particular, the dispensing mechanism includes an elongate cam member 72 formed on priming member 60 and separated from the remaining part of priming member 60 by grooves or channels 84 through which guide members 71 of chassis 66 extend. Cam member 72 extends in a circumferential direction and presents a profile adapted to provide a limited amount of flexibility. The central cam surface 74 is provided on each of two opposite sides of the cam member 72. Besides, lateral cam surfaces 73, 75 extend on either side of the priming member 60, in circumferential directions along the elongate openings 79, opposite cam member 72.
Prodgers 76 are identical to each other and clip together with cam member 72 between them. Each prodger 76 has arms 80 extending perpendicularly to a central part arranged to cooperate with central cam surface 74 of cam member 72. Arms 80 extend through elongate openings 79 of priming member 60, and have features 80a arranged at their ends to contact lateral cam surfaces 73 of priming member 60.
Elongate cam openings 79 and grooves or channels 84 of the priming member 60, and guide members 71 on the chassis 66 are arranged to hold prodgers 76 rotationally, but to allow them to move in an axial direction of the device 3, towards and away from carriers 12 by means of central 74 and lateral 73 cam surfaces that positively guide prodgers 76.
As explained in WO-A-2005/002644, actuating mechanism 52 arranges for one of prodger 76 to be in alignment with one of insert 26 of corresponding carrier 12 while other prodger 76 faces blank portion 82 of other carrier 12. In this way, the dispensing mechanism only dispenses one unitary dose 28 of one of carrier 12 at a time.
Operation of the dispensing mechanism is now described.
As illustrated in
At an initial step, when the user moves mouthpiece cover 4 to expose mouthpiece 6, priming lever 8 is in its first position and both prodgers 76 are in a retracted position at one end of cam member 72 opposite central cam surfaces 74.
When the user moves priming lever 8 to its second position, priming member 60 is rotated relative to chassis 66. Cam surfaces 74 of cam member 72 engage prodgers 76, respectively. Cam surface 74 that engages prodger 76 in alignment with one of insert 26 presses out prodger 76 so that prodger 76 is moved outwardly towards its corresponding carrier 12, penetrates through-hole 20 of carrier 12 and pushes insert 26 in the discharge position. Meanwhile, cam surface 74 that engages prodger 76 in alignment with blank portion 82 deforms thanks to its flexibility.
After the user has inhaled unitary dose 28, mouthpiece cover 4 may be rotated back by the user. The actuation rib of mouthpiece cover 4 may engage priming lever 8 to move it back to its first position. Lateral cam surfaces 73 of priming member 60 retract prodgers 76.
The indexing mechanism will now be described.
In the embodiment illustrated in
In particular, as illustrated in
The indexing mechanism further comprises a driving member 81 formed on an outer edge of priming member 60. Driving member 81 is arranged so that when priming lever 8 is moved from its first position to its second position as explained above, the dispensing mechanism push pocket insert 26 (not shown) in the discharge position, driving member 81 does not rotate Geneva wheel 100, when priming lever 8 is moved back from its second position to its first position, driving member 81 rotates Geneva wheel 100. In particular, driving member 81 is placed, in the circumferential direction, next to a portion of priming member 60 comprising the dispensing mechanism.
Driving member 81 is provided with a leading portion 101, a ratchet pawl 83 which slopes downward toward leading portion 101, and a slot 83a with a trailing edge 85 arranged in sequence. The operation of the indexing mechanism will now be described in relation to one cycle defined by the movement of priming lever 8 as it is actuated by the user. The terms “first”, “second” and “third” related to long 102 and short 103 pegs in the following description are used in relation to one cycle. It should be understood that the “first”, “second” and “third” pegs would change in a subsequent cycle.
As indicated above, when priming lever 8 is moved from its first position to its second position, driving member 81 does not rotate Geneva wheel 100. In particular, peg wheel 77 and driving member 81 are arranged so that the outer edge of priming member 60 passes over the first of short pegs 103 and slides against the first and second of long pegs 102 adjacent on either side of first short peg 103, ratchet pawl 83 deforming when passing over second short peg 103. Geneva wheel 100 is therefore prevented from rotating.
When priming lever 8 returns from its second position to its first position, leading portion 101 passes over first short peg 103 and the outer edge of priming member 60 slides against first and second long pegs 102, thereby preventing peg wheel 77 from rotating. Then ratchet pawl 83 engages with first short peg 103 so that peg wheel 77 is driven around, second long peg 102 entering slot 83a. As ratchet pawl 83 disengages first short peg 103, trailing edge 85 of slot 83a engages second long peg 102 and continues to drive peg wheel 77 around. As trailing edge 85 of slot 83a disengages the second long peg 102, the outer edge of priming member 60 passes over second of short pegs 103 adjacent to second long peg 102 and abuts against second and third of long pegs 102. The indexing mechanism causes one of each carrier 12 to be incremented by one unitary dose 28 each time priming lever 4 is actuated.
Gear teeth 35 of the coupling portion of each airway plate 34 may be in engagement with corresponding gear 78 of Geneva wheel 100 so as to be moved with respect to casing 2 successively in the active positions. The numbers of gear teeth 35 on airway plates 34 and gears 78 are arranged so that the motion of an angle of 120° of Geneva wheel 100 increments support 30a or 30b exactly one pitch.
To avoid having both first 30a and second 30b supports driven simultaneously, the indexing mechanism is caused initially to drive first support 30a and, when this has had all of its unitary doses 28 dispensed, to then drive second support 30b.
The embodiment described above is arranged to dispense the dry powder from each insert 26 of one carrier 12 and then subsequently the dry powder from each insert 26 of other carrier 12. However, it should be appreciated that it is also possible for a device to dispense dry powder from inserts 26 alternately from one carrier 12 and then other carrier 12. Alternatively, inserts 26 of both carriers may be dispensed simultaneously.
It will be appreciated that, with the arrangement where one or other of prodgers 76 abuts a blank portion 82 of a carrier 12 where there is no pocket, in order for priming member 60 to rotate and cam member 72 to move a prodger 76 towards other carrier 12, it will be necessary for cam member 72 to move away from blank portion 82. In some embodiments, it might be possible to allow the entire priming member 60 to move axially or for carriers 12 to move axially. However, in one embodiment, cam member 72 has itself a limited amount of flexibility. As illustrated, cam member 72 is provided as an elongate member which is attached to rest of priming member 60 at each end with an elongate opening either side of it. This will allow sufficient flexibility for cam member 72 to move towards and away from carriers 12.
Considering the overall embodiment as described with reference to
In the embodiment illustrated in
As the motion of the inserts 26 is restricted by first and second lidding sheets or foils 22, 24, sealing both surfaces of carrier plate 12, a high force is required to cause inserts 26 to start to move. This force increases to the point at which foils 22, 24 rupture after which the force decreases substantially. Thus, the user feels a resistance to the motion of priming lever 8 for the early part of its travel. At some point along its travel, the resistance suddenly reduces, as foil 22, 24 rupture. The user cannot reduce the applied force instantaneously so that priming lever 8 is rapidly pushed to the end of its available stroke. This tactile feedback encourages the user to fully open the pockets.
In this way, reliable opening of the pocket is achieved using components that can be manufactured using conventional materials and molding processes.
In one embodiment, the indexing of the two carrier assemblies (
A useful indexing mechanism described in WO-A-2005/002644 uses a 3 peg Geneva wheel 100 that rotates exactly 120° each time the indexing mechanism is actuated. The Geneva wheel 100 has two gears co-axial with the peg-wheel arranged so that the gears can engage with teeth 35 on the airway plates 34.
To avoid having both airway plates 34 driven simultaneously, it is arranged that, at one location around airway plate 34, gear teeth 35 are missing. As a result, at this location, rotation of Geneva wheel 100 does not rotate airway plate 34. Thus, the indexing mechanism drives first carrier 12 via Geneva wheel100 and its gears until it reaches the end of gear teeth 35 for that carrier 12. The next indexing moves first carrier 12 to its non-driven position, i.e. where gear teeth 35 are missing, and engages a changeover mechanism which rotates second carrier 12 until its gears 35 are engaged with the gears on Geneva wheel 100.
Rotary priming member 60 incorporates many of the functional elements described previously within a single molded component. It includes priming lever 8, cam member 74, prodger 76, and ratchet 83, as well as being the driving member for indexing Geneva wheel 100.
As described previously, for the device to operate with two disk carrier plates, in some applications, a changeover mechanism is provided to cause the indexing mechanism initially to drive a first disk and, when this has had all of its pockets opened, to then drive a second disk. Such a changeover mechanism is described in WO-A-2005/002644, incorporated herein by reference as if set forth in full. The changeover mechanism allows the same indexing mechanism to initially index a first carrier disk and then, at a predetermined location, index both carrier disks together for one increment and then subsequently cause the indexing mechanism to only index the second carrier disk. The changeover action can be initiated solely by the angular position of the first carrier disk requiring no other input from the user and providing insignificant difference in the tactile feedback. In one embodiment, the indexing of the two carrier assemblies (
Clip 125 also shown in
Thus, changeover from the indexing of one disk to the other is achieved automatically and with minimal number of components and in a very small space.
The indexing of the device, in addition to moving the next pocket into alignment with prodgers 76, in some aspects, it actuates a dose counter that provides a visual indication to the user of the number of doses remaining. The operation of a useful dose indicator for the embodiment illustrated in
It is useful that the device, when dispensing medicament, indicates to the user the number of doses remaining in the device. It is also useful that such indication is easily readable and, as such, very small numbers indicating the remaining doses would be a disadvantage. Within the size constraints of a pocket portable device that contains 60 doses providing such a display is challenging.
The simplest arrangement of marking the carrier disks with numbers visible through windows in the case work requires, where two carrier disks are used, the user to view different windows and, in addition, the space available around the carrier disk means that the size of the numbers would be small.
A useful method is to employ a display with separate units and tens indication, driven such that the tens display index one number as the unit display index from 9 to 0. This allows larger numbers to be used within the same casework. The two disks may be provided concentrically one within the other and, in some cases, coaxially with the axis of the device, for instance on shaft 68 illustrated in
In one embodiment, the display counts down to zero, but the tens disk is not provided with a “0”. Instead, it is provided with an indicator, for instance a symbol or color light to indicate to the user that the device is nearing the end of its functional life.
One embodiment uses another Geneva and gear arrangement that is driven from the movement of the carrier disks. It is indicated that a single counter is increment initially by the motion of the first carrier disk and subsequently by the motion of the second carrier disk such that the fact that the device contains two carrier disks is not apparent to the user.
After the last dose has been used, the remaining doses display will read 0 indicating that the device is empty to the user. However, if the user does not look at the display, they may actuate the device again when desiring further doses. A suitable device will provide some positive feedback to the user, as it is being actuated, that it is empty.
This feedback can be in the form that priming lever 8 cannot be moved to its operating position with the level of force normally used. This tactile feedback provides a lockout feature.
A useful method of achieving this with the two disk device is to arrange that after the last dose has been used, the second disk indexes such that it has no pocket under the prodger. At this point, two prodger members 76 both face surfaces of the disks without pockets. Thus as priming lever 8 is moved, neither prodger member 76 can move onto a disk and the resulting force on prodger members 76 is transmitted back through the drive mechanism to priming lever 8 and hence to the user.
While the user may be able to apply sufficient force to move priming lever 8 through to its home position, this will only be possible by forcing the disks to separate against the constraint of the casework. The force required to do this can be made sufficiently greater that the normal actuation force as to be obvious to the user.
Inhaling devices can be and are sometimes misused. For example, where the user did not push the priming lever substantially to the end of the stroke, returning it from this point will advance the disk to the next dose and decrement the counter, even though a dose has not been made available for inhalation. This happens approximately one third of the way through the stroke, well before the pocket is opened.
In the event of misuse, the actuation step cannot be easily paused in the misuse region. If the priming lever is returned before the pocket is opened, the device will index and count despite no dose being delivered. This behavior can be repeated for multiple actuation cycles. As a result, the device has a rising force throughout the misuse region as illustrated in
To reduce or even eliminate the potential for misuse of an inhaler by not actuating the priming lever fully or through a nonconformance with instructions for use, the geometry of the chassis and the priming member of the actuating mechanism can be improved. For example, other embodiments for the chassis of the actuating mechanism of an inhaler are shown in
As distinct from chassis assembly 58 shown in
In some applications, chassis incorporating a shelf element may distort the chassis structure by rendering the Geneva indexing mechanism too flexible. To overcome potential distortions additional supporting structures are provided as illustrated in
As distinct from chassis assembly 58 shown in
The actuating mechanism of inhaler 1 can include other embodiments of the priming member as illustrated in
Rotary priming member 260 incorporates many of the functional elements described previously within a single molded component. It includes priming lever 208, cam member 274, prodgers (not shown), and flexible cantilever blade 283, as well as being the driving member for indexing Geneva wheel 100.
Driving member 281 is provided with a leading portion 201 which contains a cut out to facilitate assembly, flexible cantilever blade 283 which can travel over and under chassis shelf 300 or 400 illustrated in
Another embodiment of the priming member of the actuating mechanism is illustrated in
Rotary priming member 360 incorporates many of the functional elements described previously within a single molded component. It includes priming lever 308, cam member 374, prodgers (not shown), and flexible tapered cantilever blade 383, as well as being the driving member for indexing Geneva wheel 100. Flexible cantilever blade 383 which can travel over and under chassis shelf 300 or 400 illustrated in
The misuse of the actuating mechanism comprising the chassis and priming members illustrated in
On the actuation stroke, the cantilever blade passes over the shelf on the chassis, bypassing the Geneva indexing mechanism, and the end of the shelf is synchronized with dose opening. If the priming lever is not pushed substantially to the end of stroke, the cantilever blade will return on the top of the shelf without indexing the disk or the counter, which will correctly indicate that no dose has been taken. During a correct actuation (to the end of a stroke) the cantilever blade will drop off the end of the shelf just after the dose opens. When the priming lever is returned, the cantilever blade then passes under the chassis shelf where it can engage with the Geneva indexing mechanism to advance the disk insert to the next dose and decrement the counter.
The priming member incorporates many of the functional elements described previously. It includes priming lever 414, cam member 421, prodger 420, and cantilever blade 422, as well as being the driving member for indexing the Geneva wheel.
The priming member includes a cantilever blade configured to engage a chassis of the inhaler, the cantilever blade 422 has a proximal portion 423, a body 424 and a distal portion, the body being disposed between the proximal portion and the distal portion of the cantilever blade and the cantilever blade having a flexible portion 427 extending with the proximal portion of the cantilever blade to allow movement of the cantilever blade relative to the chassis. The cantilever blade is angled in a direction toward the chassis (e.g., in a downward direction) at about 5, 10, 15, 20, 25, 30, 35 to about 40 degrees. The flexible portion is a hinge flexure allowing the cantilever blade to move in an upward and downward direction relative to the chassis. The cantilever blade allows a uniform delivery of the medication and the accurate counting of the dose of the medication.
Adjacent the cantilever blade is a first gap 428 that is formed between the priming member and the cantilever blade. This gap, among other things, allows space for vertical movement of the cantilever blade relative to the chassis and/or priming member.
In the illustrated embodiment, the prodger 420 is mounted on the priming member, and lateral cam surfaces 416 and 418 are arranged on the priming member to provide stability to the inhaler.
The priming member incorporates many of the functional elements described previously. It includes priming lever 521 and cantilever blade 512, as well as being the driving member for indexing the Geneva wheel.
The priming member includes a cantilever blade 512 configured to engage a chassis of the inhaler, the cantilever blade having a proximal portion 510, a body and a distal portion 514, the body being disposed between the proximal portion and the distal portion of the cantilever blade and the cantilever blade having a flexible portion 508 extending with the proximal portion of the cantilever blade to allow movement of the cantilever blade relative to the chassis. The cantilever blade is shown as a triangular shape that is angled in a direction toward the chassis (e.g., in a downward direction) at about 5, 10, 15, 20, 25, 30, 35 to about 40 degrees. The flexible portion can be a hinge allowing the cantilever blade to move in an upward and downward direction relative to the chassis. The cantilever blade comprises a tip 516 that can be tapered and angled as shown. The cantilever blade allows a uniform delivery of the medication and the accurate counting of the dose of the medication.
Adjacent the cantilever blade is a first gap 520 and a second gap 518 that is formed between the priming member and the cantilever blade. These gaps, among other things, allow space for vertical movement of the cantilever blade relative to the chassis and/or priming member. It will be understood that the flexible portion 508 may be made from the same material as the priming member. It can be designed with a hinge, in some embodiments, a joint to allow vertical movement of the cantilever blade relative to the priming member and/or chassis. First gap 520 and second gap 518 can be parallel or substantially parallel to each other and extend longitudinally with at least a portion of the cantilever blade 512. In some embodiments, the cantilever blade is adapted to pass over a portion of the chassis upon actuation of the inhaler and under a portion of the chassis upon indexing of the inhaler.
The priming member incorporates many of the functional elements described previously. It includes priming lever 604 and a cantilever blade, as well as being the driving member for indexing the Geneva wheel.
The priming member includes a cantilever blade configured to engage a chassis of the inhaler, the cantilever blade having a proximal portion 616, an angled body 620 and a distal portion 610, the body being disposed between the proximal portion and the distal portion of the cantilever blade and the cantilever blade having a flexible portion extending with the proximal portion of the cantilever blade to allow movement of the cantilever blade relative to the chassis. The cantilever blade is shown as a rectangular shape and has an elevated portion 618 that is angled in a direction away from the chassis (e.g., in an upward direction) at about 5, 10, 15, 20, 25, 30, 35 to about 40 degrees. The flexible portion can be a hinge allowing the cantilever blade to move in an upward and downward direction relative to the chassis. The cantilever blade comprises a tip that can be chamfered as shown. The cantilever blade allows a uniform delivery of the medication and the accurate counting of the dose of the medication.
Adjacent the cantilever blade is a first gap 612 and a second gap 614 that is formed between the priming member and the cantilever blade. These gaps, among other things, allow space for vertical movement of the cantilever blade relative to the chassis and/or priming member. It will be understood that the flexible portion may be made from the same material as the priming member and have a reduced thickness or an increased thickness relative to the rest of the cantilever blade to function as a hinge to allow movement of the remainder of the cantilever blade. It can be designed with a hinge, in some embodiments, a joint to allow vertical movement of the cantilever blade relative to the priming member and/or chassis. First gap 612 and second gap 614 can be parallel or substantially parallel to each other and extend longitudinally with at least a portion of the cantilever blade. In some embodiments, the cantilever blade is adapted to pass over a portion of the chassis upon actuation of the inhaler and under a portion of the chassis upon indexing of the inhaler.
The upper angled chamfer 706 is angled to cooperate with the cantilever tip 394 and to direct the cantilever tip 394 upward and over the chassis shelf 702. The lower angled chamfer 708 is angled to cooperate with an angled end 387 of driving member 381 and to direct the cantilever tip 394 under the chassis shelf 702. In some embodiments, the angled chamfers 706, 708 and/or the angled end 387 of driving member 381 can be angled from about 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39 to about 40 degrees relative planar chassis shelf.
As discussed above, to optimize the interaction with a chassis shelf, cantilever tip 394 contains angled chamfers that can have an angle from about 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39 to about 40 degrees relative planar chassis shelf. Cantilever tip 394 is also angled to optimize interaction with upper angled chamfer 706.
Both cantilever blade 383 and driving member 381 pass under the chassis shelf 702 on actuation, so that the trailing edge 710 of the chassis shelf 702 has only one chamfer 712 facing downwards (
It will be apparent to those skilled in the art that various modifications and variations can be made to various embodiments described herein without departing from the spirit or scope of the teachings herein. Thus, it is intended that various embodiments cover other modifications and variations of various embodiments within the scope of the present teachings.
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/US2018/041424 | 7/10/2018 | WO | 00 |