Patent Application
20140371690
The present invention relates to dispensing systems in general and more especially to applicators for applying medicated preparations to the scalp and scalp margins, and to other body areas, especially for applying medicated gel to a person suffering from psoriasis. More particularly, the invention relates to dispensing systems and applicators for use with medicament cartridges, and to cartridges for use in the dispensing systems and with the applicators.
Psoriasis occurs when the usual cycle of replacing skin cells is accelerated. While psoriasis presents itself as a skin condition, in recent years it has been established that its origins lie in the immune system. Normally skin cells take about 21-28 days to replace themselves, but in psoriasis sufferers the skin cells can be replaced as rapidly as every 2-6 days. This acceleration results in an accumulation of skin cells on the skin surface, often referred to as psoriasis plaque.
Patches of psoriasis, or plaques, can occur more or less anywhere on the body, but most often occur on the elbows, knees, lower back and scalp. Typically, it appears as patches of raised, red skin covered in silvery white scales. The scales are the accumulation of skin cells that are waiting to be shed and the red patches occur as a result of an increase in the number of blood vessels necessary to support the raised volume of cell production.
Frequently, plaques are itchy and uncomfortable, or worse painful or sore and a range of treatments are available to alleviate the condition. Treatment options include topical therapies, phototherapy, systemic medication and biological injections. Treatment is selected according to the severity of the condition, but in most cases topical therapies are preferred, at least at the outset as they carry lower risks and are more convenient for the patient.
For many psoriasis sufferers, topical therapies, that is preparations applied directly to the skin, are sufficient to keep the condition under control. Conventional preparations include those based on one or more of vitamin D, coal tar, dithranol, vitamin A and steroids and are supplied as semi-solid formulations.
Usually, the formulations are prescribed by medical personnel together with a dosage regime defining the amount of medicament to be applied and the frequency of application. Medications are generally supplied in tubes from which an amount is squeezed out for application to the skin area being treated. Often, the amount to be applied is defined in terms of finger-tip units (FTUs), one finger-tip unit being the distance from the tip of an adult finger to the first crease of that finger, and the number of FTUs to be applied depends on the area of application, so the dose is determined according to the skin area being treated.
A number of psoriasis sufferers interviewed on behalf of the Applicant have indicated that reliable dosing is a significant problem. An FTU is an inaccurate measure since it will vary from person to person. If only a small area of skin is affected, a sub-FTU may be required which again is difficult to measure. Obviously, if insufficient medicament is applied, the affected skin will not be soothed or heal as well as it otherwise might under the correct dosage. On the other hand, application of medicament over and above the prescribed dose can have more serious consequences. For example, overdosing of topical treatments can cause severe irritation and burning. Overdosing of formulations such as steroid creams can result in absorption through the skin and unwanted side effects, such as those that may be experienced when systemic doses of steroids are taken.
One common side effect of regular steroid use is thinning or weakening of the skin. Even if steroid cream is applied to a psoriasis area in the correct FTU dosage, there will often be weakening of the skin at the user's fingertips from using them to rub in the cream. Wearing of gloves to apply steroid medication to avoid this problem is recommended but users find this cumbersome, messy and impractical.
For patients with associated psoriatic arthritis, the action of squeezing a bottle or tube of medication can be awkward and/or painful which adds to the difficulty of dispensing a controlled dose.
Further complications arise when the skin area to be treated includes the scalp or scalp regions, such as on the forehead, neck and behind the ears. Hereinafter, references to the scalp include references to the scalp regions. Self-administration can be problematic because the area being treated may not be readily visible; without assistance, medication may have to be applied “blind” to the back of the scalp. Treating the scalp is further complicated by the need to part the hair to expose the affected area(s), and even then much of the medication inevitably ends up spread over the hair rather than the scalp, thus reducing the effective dosage.
The Applicant has therefore identified a need for a medicament applicator for applying semi-solid preparations, such as psoriasis ointments or gels and the like, to body areas including the scalp which overcomes or at least mitigates one or more of the aforementioned problems.
The term medicaments or preparations used herein is intended to embrace medicated creams, gels, ointments and the like that can flow or be extruded and spread for topical application. The terms are used interchangeably throughout, thus references to ointments, gels or the like should be construed as including other forms of semi-solid preparation. Of course, while the applicators and dispensing systems hereinafter described are particularly intended for use in delivering medicated preparations, they may also be used for delivering non-medicated preparations and such use is embraced in the statements of invention and description of preferred embodiments.
From a first aspect, the invention resides in a hand-held applicator for self-administration of a semi-solid medicament directly to the scalp, the applicator comprising:
As will be understood, by virtue of the applicator head and body being fixed relative to each other, a user may, for example, first locate a nozzle or nozzles on the scalp in the area to be treated and then deliver a dose of medicament to that area without the nozzle or nozzles moving away from the scalp when the actuator is operated. In this way, the user can be confident that the dose of medicament is delivered to the scalp rather than into the hair. Once the dose has been expelled onto the scalp, the user can then spread the medicament in that vicinity using the nozzle or nozzles. Thus the delivery and application of medicament can be achieved without lifting the nozzles from the scalp.
From another aspect, the invention resides in a hand-held applicator for self-administration of a semi-solid medicament directly to the scalp, the applicator comprising:
The applicator according to this further aspect can therefore be adapted, either by the user or by the supplier, to suit the severity of the condition being treated. Preferably the applicator head and applicator body are fixed relative to each other in use such that movement of the nozzle or nozzles away from the scalp during actuation may be avoided.
From a yet further aspect, the invention resides in a hand-held applicator for self-administration of a semi-solid medicament directly to the scalp, the applicator comprising:
The applicator according to this aspect offers ultimate versatility in that a user can select whether to dispense from a single nozzle only, suitable for application in small or awkward areas, or from all nozzles, suitable where the area to be treated is more extensive and more readily accessible, and if desired to dispense a single dose from one nozzle or a multiple of the single dose through all nozzles. Again, the applicator head and applicator body are preferably fixed relative to each other in use such that movement of the nozzle or nozzles away from the scalp during actuation may be avoided.
It will of course be appreciated that a patient may often have patches of psoriasis over a number of body areas, including on the scalp and elsewhere. In the past, treatment has involved the application of one medicated preparation to the scalp and a different preparation to other body areas, for example, the application of a gel formulation to the scalp and a more viscous, creamy formulation to other areas of skin. However, this adds a further level of inconvenience to a user for whom the use of a single formulation irrespective of the area being treated is desirable.
Accordingly, and from yet another aspect, the invention resides in a hand-held applicator for targeted self-administration of a semi-solid medicament directly to the scalp and to other body areas, the applicator comprising:
The applicator according to this further aspect is particularly suitable for use by patients as both a scalp applicator and body applicator. Specifically, the nozzle is able to penetrate the hair to allow medicament to be delivered directly to the scalp, whereupon the nozzle can also assist in spreading the medicament over the scalp in the same vicinity. Equally, the nozzle is able to deliver medicament directly to another body area, such as on the arms or legs, whereupon the application face can be used for spreading the medicament over the desired body area. Thus the applicator can be used universally by all psoriasis patients, irrespective of whether the plaque region is large or small, on the body or on the scalp. Moreover, where the medicament charged to the reservoir is suitable for use on both the scalp and the body, a patient may use the same applicator to apply the medicament to all affected areas, avoiding the need to have separate applicators for the scalp and the body.
Again, the applicator head and applicator body are preferably fixed relative to each other in use such that movement of the nozzle away from the scalp or skin during actuation may be avoided.
It will be understood that applicators according to all aspects of the invention as described herein may include such an application face, thereby making those applicators also especially suitable for use in applying medicament to body areas other than the scalp.
Various preferred features of the applicators according to any one or all of the above aspects are described below. It will be understood that the features described are generally applicable to all aforementioned aspects of the invention, unless stated to the contrary, and to the dispensing systems that are described more generally hereinafter.
The applicator according to the present invention desirably comprises an airless delivery system whereby the medicament is substantially isolated from contact with air whilst within the applicator. As well as guarding against oxidation and hence deterioration of the medicament through contact with air, providing an airless system also ensures reliability in delivering an accurate dose to the scalp or other body area. Furthermore, with an airless system, the applicator may be held in any orientation whilst dispensing medicament. In other words, the applicator body may be held in a substantially upright orientation, or be inverted, or be in any orientation in between, during application of the medicament, thus helping make application easier for the user.
For helping ensure the reserve of medicament is stored and maintained in an airtight manner prior to use, the medicament is preferably supplied in a cartridge. Thus the applicator preferably includes a cartridge port for receiving a dispensing end of a cartridge charged with medicament, the port being in fluid communication with the or each inlet to a respective pump chamber of the pump assembly. The cartridge port is most conveniently provided on the applicator head. The cartridge port is preferably adapted to engage with the cartridge and seal around the cartridge outlet, for example by means of an interference (push) fit, screw fit or bayonet fit, thereby avoiding leakage of the medicament between the cartridge and cartridge port once the cartridge has been fully fitted. The cartridge port may comprise a seal for sealing with the dispensing end of the cartridge, for example sealing against an external wall of the cartridge, such as around a neck or nozzle portion thereof, or against an internal wall thereof, such as inside the neck portion, or both. In a simple form, the seal may comprise an O-ring seal on the applicator, or, in a preferred arrangement, the cartridge port may include a stopper that seals against an internal wall of the dispensing end of the cartridge, preferably a neck portion. In the latter case, the stopper preferably includes a central bore for permitting medicament to flow from the cartridge to the pump chamber via the inlet. More preferably, the inlet to the pump chamber is integral with the stopper.
Typically, the cartridge will be supplied with a cartridge cap, usually a plastic cap, which is removable prior to fitting the cartridge to the applicator. In order to reduce the risk of damage to the cartridge nozzle or neck in the event that the cartridge is dropped, for example, the cartridge cap is preferably strengthened such as in double walled, most preferably in the form of an H-section. This ensures that if dropped, the outer wall of the H-section absorbs at least some of the energy by means of the plastic deformation rather than the energy being transmitted to the nozzle, and which may otherwise result in nozzle fracture or breakage. Alternatively, instead of a cap or in addition thereto, the cartridge may be provided with a seal, such as a foil seal, over the outlet thereof at its dispensing end which seal is removable prior to fitting or which is piercable by the applicator when the cartridge is fitted thereto.
The cartridge may comprise a collapsible container, such as a bag, typically a foil bag, preferably supplied within a rigid housing (so-called “bag-in-bottle” technology) but more preferably the cartridge comprises a substantially rigid container, such as a tube. Most preferably, the cartridge comprises a tube provided internally with a plunger in sealing contact with the inner tube wall, for example having twin lip seals or other such resilient seal(s), which is drawn up towards the cartridge outlet as medicament is discharged. The plunger maintains an airless environment for the medicament within the cartridge.
In one arrangement the cartridge may be integral with the applicator body, thus the applicator body may consist essentially of the cartridge. Alternatively, the cartridge may be separate from, but accommodated at least partially within, the applicator body. In either case, once a cartridge has been depleted, it may simply be detached and withdrawn from the cartridge port and a fresh cartridge inserted. Thus the applicator head, the pump assembly and where applicable the applicator body may be re-used any number of times. In a further alternative arrangement, the applicator may be fully disposable, the applicator head, pump assembly and actuator being disposed of with the cartridge once the cartridge is depleted. In the latter case, the cartridge may include one-way locking features to prevent re-use.
In a particularly preferred arrangement, the applicator head, pump assembly and actuator are provided as a unit, thereafter also referred to as the head assembly, and the applicator body consists essentially of a medicament cartridge adapted to fit with the applicator head. Thus, the applicator is assembled ready for use by attaching a charged cartridge to the head assembly. More preferably, the head assembly and cartridge are each provided with complementary interlocking or non-return features for preventing separation of the cartridge from the head assembly once the cartridge has been fitted. For example, the dispensing end of the cartridge may be provided with an inwardly directed flange and the cartridge port on the applicator head may be provided with a lip seal, such as on the stopper that is inserted into the neck of the cartridge. As will be understood, once the lip seal has advanced beyond the return flange of the cartridge neck, it is no longer possible to separate the cartridge from the applicator head without destroying the seal or breaking the flange. Alternatively, the stopper may be provided with an annular groove for interlocking with an annular bump on the internal wall of the cartridge neck. Thus once the stopper has been fully inserted into the cartridge neck, the bump is held in the groove and again it is difficult to prise the applicator head off the cartridge without breaking the connection.
In a yet further alternative “once-only” fit arrangement, the cartridge and the head assembly may comprise complementary screw threads whereby the cartridge may be screwed on to the head assembly, and a plurality of spaced apart ribs are provided around the cartridge neck and one or more, preferably two, flexible tabs are provided on the cartridge port whereby the ribs are able to depress and ride over the tabs when the cartridge is screwed on to the head assembly but are unable to depress the tab(s) in the reverse direction, thereby preventing separation (unscrewing) of the cartridge from the head assembly.
On the other hand, where the applicator is intended for re-use and the applicator body is separate from the cartridge, the body may comprise a hollow container, typically a cylinder, open at the distal end (the end furthest from the pump assembly) to allow insertion of the cartridge. Advantageously the cylinder is of a length such that the end of the cartridge, when inserted in the cylinder and fitted to the cartridge port, extends beyond the distal end of the cylinder thus permitting the cartridge still to be gripped whilst it is being secured, for example by push-fitting or screwing, to the cartridge port. For allowing a user to check which medicament is fitted to the applicator, the distal end of the cartridge may carry a visual indication of its contents.
In one arrangement the cartridge has a length that extends beyond the end of the applicator body when fitted such that the exposed length of cartridge is gripped by a user during application of the medicament. Alternatively the cartridge may be substantially enclosed within the applicator body. An end cap, either supplied on the cartridge at the distal end thereof, or as a component of the applicator, may be provided to close the open end of the applicator body with the cartridge retained therein. The end cap may also serve to help retain the cartridge in position with respect to the cartridge port which leads directly or indirectly to the fluid inlet of the pump assembly. The end surface of the end cap for the applicator body or of the non-dispensing end of the cartridge, as appropriate, is preferably flat or otherwise contoured to support the applicator in a substantially upright position, nozzle(s) uppermost, for storage purposes.
As will be appreciated, prior to delivering an initial dose of medicament, the applicator must first be primed so that the pump chamber and dispensing nozzle or nozzles are fully charged with medicament. The priming operation may be automatic or manual, for example manual priming may be performed by operating the actuator to pump the medicament from the applicator body into the pump chamber and out through the or each nozzle; once medicament begins to emerge out of the or each nozzle the applicator is fully primed and ready for use. Any medicament expelled from the nozzle(s) during priming may be wiped away so that the next operation of the actuator will result in a precise known volume, i.e. a dose, of medicament being dispensed. The dose that is dispensed typically comprises medicament from the nozzles, and the volume of the dose dispensed corresponds to the volume of medicament displaced from the or each pump chamber.
Inevitably, due to filling and manufacturing tolerances, the fill height of medicament in the cartridge may vary to such a degree that priming by operation of the actuator alone is impractical. For example, even if only 0.5 cm3 of air is to be evacuated from the cartridge neck itself, this could require approximately 30 pumps of the actuator to displace the air from the cartridge neck and from the pump chamber and nozzle of the head assembly before medicament emerges from the nozzle tip.
Accordingly, as an alternative to priming by operation of the actuator alone, or to reduce the number of times the actuator has to be pumped in a priming operation, the cartridge and applicator head, or at least the cartridge port thereof, may be configured in such a way as to evacuate some or all of the air as the cartridge is fitted to the head. For example, as described hereinabove, the cartridge port may comprise a stopper for fitting into the neck of the cartridge, with the stopper being provided with a vent through which air displaced by the stopper as it is pushed into the neck of the cartridge is forced. displaces air the stopper having a central bore through which medicament from the cartridge is permitted to flow to the pump chamber. The stopper bore may therefore provide the pump inlet to the pump chamber. Preferably, the stopper bore has a first portion of a first diameter and a second portion of a second diameter which is larger than the first diameter, and a bridging portion between the first and second portions forming a valve seat for an inlet valve to the pump chamber. The bridging portion most preferably comprises an inverted, truncated conical surface acting as a valve seat, such as for a spherical or hemispherical valve, especially a ball valve or the like.
The stopper preferably has a length sufficient to displace some or all of the air that may initially be present in the cartridge, typically above the fill level at the dispensing end, as it is advanced into the cartridge neck.
For ease of insertion and to create an effective seal with the cartridge neck, the stopper may be provided with a lip seal around its outer face. The lip seal forms a continuous seal with the cartridge neck yet requires less pressure on insertion than if the entire outer face were itself to provide the seal.
In one arrangement, a side wall of the stopper may be provided with a thread-like channel, such as in the form of a helical lip seal, in fluid communication with the stopper bore for permitting air to escape as the stopper is advanced into the cartridge. Since the medicament is not easily forced through the thread-like channel, when the forward end of the stopper reaches the medicament and starts to displace that, a large back pressure is built up inside the cartridge. This back-pressure may serve to push back the plunger, if provided, at the opposite end of the cartridge, thereby largely avoiding any overspill of medicament during priming. Accordingly, the cartridge preferably has capacity to accommodate such reverse movement of the plunger as may occur during priming of the applicator.
While the stopper may comprise a substantially solid member, it may alternatively comprise a substantially hollow member. For example, the stopper may comprise concentric inner and outer cylindrical walls, joined at the insertion end to prevent ingress of medicament, other than through the central bore created by the inner cylindrical wall that provides the passageway for medicament to be dispensed from the cartridge. The outer cylindrical wall preferably seals against the end surface of the cartridge neck when the cartridge is in its fully inserted position, for example by means of an outwardly directed flange at its end or a lip seal around the outer circumference adjacent the end. Such a hollow stopper may be comprised of a compressible material to enhance the quality of the seal. Irrespective of whether the stopper is of solid or hollow construction, the external or outer wall may narrow in diameter towards the insertion end to provide a taper for facilitating entry into the cartridge neck.
The cartridge port may comprise a cap member that co-operates, such as by interlocking, with the external wall of the cartridge neck to retain the cartridge in sealing engagement with the applicator head. For example, the cap member may have an internal thread that engages with an external thread on the cartridge neck. Such a cap member has an aperture for allowing medicament to flow into the pump chamber.
In one arrangement, the cartridge port may comprise a stopper attached to a cap member such that the stopper is advanced internally and the cap is advanced externally of the cartridge neck. Preferably, when the stopper is provided with an outwardly directed flange, the cartridge is fitted to the cartridge port by initially pushing the applicator head or head assembly onto the cartridge and then screwing the cartridge to secure and tighten the connection, the screwing action also serving to compress the flange between the upper edge face of the cartridge neck and the cap member thereby sealing the cartridge with respect to the head assembly such that medicament may only be discharged via the central bore. As discussed above, any back pressure created during fitting of the cartridge may be released by reverse movement of the cartridge plunger.
In another arrangement, the neck of the cartridge may be double-walled, the walls spaced sufficiently apart to create a chamber therebetween for accommodating any overspill of medicament as the stopper is advanced into the neck of the cartridge and air evacuated. In this way, any medicament that is displaced during priming is held in the chamber between the neck walls and is prevented from leaking from the applicator. In this arrangement, the stopper may further comprise a cap portion, as an alternative to a separate cap member, which provides a seal with the outer neck wall. Further, the cap portion may also create a seal with the inner neck wall so that medicament in the cartridge does not come into contact with any air that remains in the neck chamber, nor can any medicament that has overspilled into the neck chamber be returned to the cartridge. For example, the cap portion preferably has two concentric walls depending from the internal end face thereof, the walls extending so that they seal against the inner and outer neck walls respectively only when the stopper has been advanced almost to its full extent. In this way, the seals are created after the air has been virtually fully evacuated through displacement by the stopper and then by the medicament as the stopper is advanced.
A yet further alternative arrangement for priming the applicator may reside in the configuration of the cartridge cap that seals the cartridge during storage and is removed therefrom prior to the cartridge being fitted to the applicator head. In particular, the cartridge cap may comprise a priming insert for the non-dispensing end of the cartridge, whereby after detaching the cap from the dispensing end it is inserted into the non-dispensing end to advance the cartridge plunger from behind. In this way, the cartridge cap acts as a tool to drive the plunger and thereby evacuate air through the applicator head. The cartridge cap may also be used in this way in conjunction with the other priming arrangements described above. While the cartridge cap/priming insert may be retained in the rear end of the cartridge after priming, it is preferably removed and discarded. In this way, a user of the applicator can view the position of the plunger by looking into the non-dispensing end of the cartridge and thereby gauging the extent to which the cartridge has been depleted.
The priming insert may comprise an outer wall including a first portion having a circumference substantially the same as the outer circumference of the main cartridge body and a second portion having a circumference smaller than the outer circumference to allow insertion into the non-dispensing end of the cartridge body for advancing the plunger. Preferably the second portion has a circumference that permits sliding along the inner cartridge wall, and a length sufficient to advance the plunger to complete priming before the first portion abuts the end of the cartridge whereupon further insertion is prevented. The priming insert preferably includes a threaded portion or the like for engaging with a complementary engaging feature on the cartridge neck and securing the insert to the neck portion as the cartridge cap. Further, the cartridge cap or insert desirably has a recessed portion that extends into the cartridge neck when fitted thereto, the recessed portion occupying a volume of the neck portion thereby to limit the volume of air that resides in the cartridge at the neck portion when the cap is in place. In this way, the medicament within the cartridge is not exposed to a volume of air that may be prejudicial to the quality of the medicament.
Turning to the dispensing nozzle or nozzles of the applicator, these preferably project at an inclined angle with respect to the applicator body and, where more than one nozzle is provided, the nozzles preferably extend parallel with each other. By having the nozzle(s) inclined with respect to the applicator body, a user does not have to reach so far to access awkward areas of the scalp, such as at the rear of the head, the applicator is more comfortable to hold, especially against the scalp, and the nozzle can be gently laid against the skin when used to dispense medicament to a body area. The nozzle tip may project beyond the outer circumference of the applicator body.
In one arrangement, the nozzle or nozzles may project substantially normally from an inclined face of the applicator head. This arrangement is advantageous not only in terms of helping reduce stress, especially when two or more nozzles are being used to massage medicament over the scalp, but also enabling a more direct, unrestricted flow path for the medicament.
As described hereinabove, the applicator may comprise an application face for spreading dispensed medicament over a body area other than the scalp. In such an arrangement, the application face is preferably disposed adjacent the dispensing nozzle(s), preferably adjacent a single nozzle. More preferably, the dispensing nozzle is contiguous with the application face, rather than projecting from a part of the applicator head separate from the application face.
In order to facilitate spreading of medicament, the application face is preferably substantially planar or gently convex. Moreover, to avoid scraping of the user's skin when spreading medicament, the outer edges, or perimeter, of the application face are preferably rounded. Most preferably the application face is substantially circular or ovoid.
The application face may be inclined with respect to the applicator body, such that a user can deliver medicament to the body from the nozzle and spread the medicament using the application face simply by adjusting the orientation of the applicator relative to the body, that is, without requiring relative movement between the applicator and the user's hand. Thus the dispensing of medicament and subsequent spreading thereof on the user's scalp or skin can be achieved without the user needing to alter his grip on the applicator.
In one preferred arrangement, the application face, which typically is planar or gently convex, may include a tapered portion comprising part of the nozzle. In other words, part of the nozzle's external surface comprises an extension of the application face, preferably the application face and nozzle together present a substantially teardrop-shaped face, with the apex comprising the nozzle. When the applicator is stood on end, that is with the non-dispensing end of the cartridge or the end cap of the applicator body acting as a base, the application face and nozzle together preferably comprise an upwardly facing, inclined surface of the applicator.
Other ergonomic arrangements of the applicator face and nozzle are also contemplated, such as the provision of a sideways facing application face, that is an application face lying substantially parallel with the longitudinal axis of the applicator body. In this orientation, the nozzle may still extend substantially continuously with the application face and at an inclined angle with respect to the longitudinal axis. Alternatively, the applicator comprises a pair of opposing sideways facing application faces with the nozzle extending from and substantially continuous with both faces; this arrangement is particularly versatile and easily used by both left and right handed persons.
In a further alternative arrangement, the application face may be provided substantially underneath the nozzle. For example, when stood on its base (such as provided by an end cap on the applicator body or the non-dispensing end of the cartridge), a generally upwardly inclined nozzle overhangs the application face. In such an arrangement, the application face is preferably also upwardly inclined, but in a direction opposite to that of the nozzle.
The bore of the nozzle(s) through which medicament is forced on dispensing may be substantially uniform in cross-section, or have a narrower portion towards the nozzle tip. The bore of the nozzle may in fact be provided by a tubular member or insert within the nozzle. For strength and ease of cleaning, the nozzle may flare outwards at its base (i.e. at the boundary between the nozzle and the applicator/application face), but otherwise have a generally uniform cross-section along a substantial length of its stem. More preferably, however, the external profile of the or each nozzle is tapered such that the nozzle cross-section decreases gradually along its length towards the nozzle tip. Such gradually tapered nozzles have even better mechanical strength, and also provide a smoother, wipe clean surface.
The external nozzle profile may be generally cylindrical, or conical where the nozzle tapers towards its tip, but could equally be flattened in one or more planes, typically when the nozzle extends from and is substantially continuous with the application face. Desirably, as with the application face, the external profile of the nozzle includes only smooth, rounded edges, to avoid causing discomfort to the skin or scalp during application of medicament. Conveniently, the nozzles, or at least a substantial part thereof, may be moulded integrally with the applicator head.
When the nozzles extend from an applicator face, the applicator face is preferably inclined at an angle in the region of 45° to 65°, more preferably 50° to 55° and especially 52°, in relation to the longitudinal axis of the applicator body. Alternatively, when the applicator comprises an application face for spreading medicament, the application face may be substantially parallel with the longitudinal axis of the applicator body or substantially normal to said axis, or any angle therebetween, typically in the region of 20° to 60°. When parallel with the longitudinal axis, the applicator head may be offset with respect to the applicator body.
When more than two nozzles are present, as in an applicator intended primarily for use on the scalp, it is desirable that the tips of all nozzles terminate on the same plane thereby ensuring that all nozzles may simultaneously rest against the scalp. This is important to avoid medicament being dispensed into the hair and for all nozzles to remain against the scalp during the process of spreading the medicament across for desired area. In this regard, three nozzles are especially preferred since they will always be stable on a surface. In such a scalp applicator, where the nozzles project from an applicator face, the Applicant has found that a nozzle angle, that is the angle between the longitudinal axis of the or each nozzle and the longitudinal axis of the applicator body of between about 30° to 40° is suitable, more preferably about 35°.
As will be appreciated, when the nozzles extend from an applicator face, either a single nozzle, or a plurality of nozzles all of equal length, the applicator face will preferably be inclined at the same angle as the nozzle angle. However, if the nozzles are not all of equal length, the applicator face is preferably inclined at a shallower angle than the nozzle angle. For example, the angle between the plane of the applicator face and the plane substantially normal to the longitudinal axis of the applicator body (hereinafter the face angle) may be between about 30° to 60°, more preferably about 45°.
In any event, to ensure effective penetration of the nozzle(s) through most thicknesses of hair, each nozzle preferably has a minimum length of 10 mm, more preferably in excess of 15 mm, and most preferably 18 mm or more. Whilst the length of the nozzle can be increased significantly further, at least in theory, in practice any nozzle that exceeds about 30 mm becomes prone to damage and is not therefore recommended.
When two or more nozzles are present, they are preferably spaced at least 20 mm and less than 40 mm apart. More preferably between about 25 mm and 35 mm apart, especially from 27 mm to 33 mm, the lower end of the range providing a desirable spread pattern (more even scalp coverage) and the upper end of the range providing good handling stability during massaging.
For treatment of the scalp, the nozzle or nozzles will typically be “massaged” against the affected scalp once the medicament has been dispensed therefrom, or be used in a similar fashion to spread the dispensed medicament over a small body area, such as over a small plaque. For this reason, the or each nozzle is preferably provided with a tip of a softer or more resilient material relative to the material used for the major, elongate portion of the nozzle which should be relatively rigid. For example, the nozzle tips may comprise elastomeric pads or the like for permitting medicament to be spread gently over the sensitive area of the scalp. Even when the applicator is used for treatment of other body areas, the provision of a soft, resilient nozzle tip is beneficial for user comfort.
The material selected for the nozzle tip may influence the balance between feel (softness against the scalp or skin) and penetration (parting the hair). For example, a rubber tip may offer better comfort than a polymer tip, but be less efficient at penetration. Moreover, the manner in which the tips are secured to the nozzle stem may also influence the feel of the tips to a user and their penetration ability. Examples of the different ways of securing the nozzle tips to the nozzle stem include use of a headed bolt, an internal rivet and by stretching the tip over the nozzle stem.
To avoid the nozzles being blocked by the scalp or skin on discharge, or becoming blocked by loose plaque such as that generated as the nozzle tip is massaged against the scalp, instead of having an end port/opening, the discharge port may be located transversely thereto. In this way, the medicament may still be discharged directly onto the scalp where the nozzle(s) rests against the scalp, or onto the skin in other body areas, but from one or more side ports. In a preferred arrangement, the or each nozzle comprises a nozzle stem having an end port and a nozzle tip (in the form of an end cap) overlying the end port and having opposing side ports through which medicament exiting the end port is directed.
In order to help avoid ingress of any foreign material into the applicator via the nozzles, the or each nozzle may terminate in an outlet valve, such as a pin valve or a slit valve, that opens under positive pressure exerted on the medicament in the pump chamber to allow discharge of the medicament through the or each nozzle.
It is of course desirable to protect the applicator head and in particular the nozzle(s) when the applicator is not in use, and in this regard the applicator may further comprise a cap or cover for enclosing the applicator head. Preferably the protective cover fits over the applicator head and is retained thereon, for example by complementary engagement features on the cover and applicator head or applicator body, such as by a snap-fit mechanism or screw-cap, or simply by a friction fit. After the applicator has delivered a dose of medicament to the scalp and the nozzles have massaged in the medicament over the desired area, the applicator head, including the nozzles, can be wiped clean and the protective cover replaced.
Advantageously, the cover for the applicator head not only shields the application face but also serves to seal the nozzle tip or tips. Where the applicator head comprises a single nozzle contiguous with the applicator face, the cover may be shaped to encase the nozzle and the application face. More preferably, the applicator cover extends also to shield the actuator lever for avoiding accidental actuation. Such a cover may therefore extend to shield virtually the whole of the applicator head and actuator, or head assembly. By also shielding the actuator lever, inadvertent damage to the actuator when the applicator is not in use may also be avoided. As well as simply shielding the actuator lever to prevent accidental use, the cover may extend to enclose completely the lever.
In a further alternative arrangement, instead of the applicator cover extending to shield the actuator, it may instead include an actuator lock for preventing actuation. For example, the cover may include at least one locking member for insertion behind the actuator, such as under a lever arm thereof, to prevent movement of the actuator. Preferably, the cover actuator lock comprises a pair of arms that may be clipped under opposite sides of the actuator lever, more preferably each arm terminating in a projection, such as a wedge-shaped projection, to substantially inhibit any movement of the actuator lever towards the applicator body or cartridge. Ideally, the arms of the applicator cover lock are sufficiently resilient to permit them to be spread apart during fitting and cause them to spring back behind the actuator lever once released.
The pump assembly of the applicator is preferably enclosed, for example housed within the applicator body or more preferably within the applicator head, particularly as a component of a head assembly, or therebetween, when the applicator is fully assembled for use, thereby ensuring that the components of the pump can be kept clean and hygienic. Both the applicator head, including the nozzle(s) and, where provided, the application face, and the applicator body are preferably contoured in a manner that provides a substantially continuous external surface such that the applicator as a whole may be readily cleaned by wiping.
Advantageously, the or each fluid inlet of the pump assembly has an inlet valve for sealing the inlet from the medicament reservoir, such as from the cartridge, under positive pressure in the pump chamber and opening the fluid inlet under negative pressure in the pump chamber. Thus the or each inlet valve is closed when positive pressure is exerted on the medicament in the pump chamber by the actuator to effect discharge, but is opened when the pump chamber has been discharged and the actuator released. As will be understood, negative pressure created in the pump chamber immediately after discharge of a dose of medicament therefrom and concurrent opening of the inlet valve results in a further dose of medicament being drawn from the medicament reservoir through the inlet valve into the pump chamber so that the chamber and hence the applicator is ready for its next use.
The or each inlet valve preferably comprises a one-way valve, for example a simple flap valve or a check valve, such that medicament advanced to the pump chamber is prevented from being returned upstream of the inlet valve. Thus such a non-return valve ensures that the medicament supply in the reservoir is kept in isolation.
When the applicator includes a cartridge port for connecting with a medicament cartridge, the inlet valve of the pump assembly may be positioned over the fluid outlet of the cartridge port. In a preferred arrangement, the inlet valve is positioned over the central bore of the stopper, more preferably within the stopper bore, and most preferably the central bore includes a shoulder portion against which the valve member, such as the disc or ball, rests or is seated to close the inlet. The valve member may be raised above the shoulder portion under negative pressure within the pump chamber to allow medicament to flow into the chamber. The inlet valve member is preferably spring-loaded permitting opening of the inlet under negative pressure in the pump chamber (and allowing medicament to be discharged into the chamber) against the spring force, and closing the inlet under the action of the spring on equalisation of the pressure. For example, the valve may comprise a valve member, such as a disc, plug, ball or the like, and a separate spring, but may alternatively take the form of a unitary valve moulding comprising both the valve member and spring. Such a unitary valve moulding may include an anchor portion for securing the moulding with respect to the pump chamber and/or cartridge port, a disc or ball portion for closing the inlet, and a spring portion extending between the anchor portion and the disc or ball portion. As will be appreciated, both the anchor portion and spring portion are such as to permit flow of medicament into the pump chamber. In a particularly preferred arrangement, the anchor member of the inlet valve moulding may be captured between the stopper and the cap member of the cartridge port.
The or each pump chamber of the pump assembly into which medicament is drawn and subsequently discharged may comprise a collapsible chamber whereby the volume of the chamber is reduced under a force applied by operation of the actuator. Such a collapsible chamber may, for example, be in the form of a bellows where side walls of the chamber concertina, or in the form of a rolling diaphragm where an end wall of the chamber is advanced or “rolled” inwards with accompanying shortening of the diaphragm side walls, or in the form of a vertical diaphragm which is pressed down by the actuator to reduce the chamber volume. Specifically, operation of the actuator, which may comprise a lever arm and plunger or, in the case of a vertical diaphragm, an L-shaped lever arm (one arm being the lever arm and the other arm acting as the plunger), the lever arm being squeezed towards the applicator body to apply the plunger to the chamber, causes the contraction of the chamber resulting in positive displacement of a predetermined volume of medicament; the volume displaced corresponding to the desired dose of medicament. The displaced volume of medicament is forced out of its chamber through one or more fluid outlets of the pump assembly to one or more dispensing nozzles, and an equivalent volume of medicament is thereby dispensed from the nozzles.
The collapsible chamber, especially one involving a bellows or rolling diaphragm arrangement, may be comprised of a resilient material, preferably an elastomeric material. The chamber is advantageously formed, such as by moulding, in an expanded (not collapsed) configuration, such that after collapsing and release of the actuator, the collapsed chamber wall reverts to its original, expanded shape. In the case of a rolling diaphragm, for example, a negatively wound spring may be included to assist in returning the chamber wall to its original, non-collapsed state and/or to return the actuator to its initial position ready for dispensing the next dose. As the collapsible chamber expands upon release of the actuator, negative pressure is created within the chamber resulting in a further volume of medicament being drawn into the chamber via the fluid inlet ready for delivery of the next dose.
When the collapsible chamber comprises a rolling diaphragm, it is desirable for the chamber to be guided such that it collapses in a substantially linear manner. In this regard, the diaphragm may be substantially surrounded by an outer casing for guiding or restraining the side walls of the chamber to force substantially linear collapsing. Moreover, to permit the actuator to be operable on the collapsible chamber within the casing, the casing is preferably provided with an aperture aligned with a central, longitudinal axis of the diaphragm and a chamber pin is provided that extends through the aperture such that one end of the pin is in contact with the end wall of the diaphragm and the other end is contactable by the actuator. During actuation, the chamber pin is pushed from one end by the actuator and the other end of the pin therefore advances the diaphragm to discharge medicament. Thus, the chamber pin reciprocates along the longitudinal (collapsing) axis of the diaphragm.
The end of the chamber pin that contacts the diaphragm is preferably also retained by the diaphragm, for example by means of complementary engaging features on the pin and diaphragm, so that when the diaphragm springs back to its “uncollapsed” shape after dispensing, the pin remains in position against the diaphragm ready for the next operation. Without being positively retained against the diaphragm, there is a risk that the pin end may lose contact with the diaphragm under the returning force potentially resulting in misalignment with the diaphragm. In a preferred arrangement, the chamber pin includes a groove adjacent the pin end that contacts the diaphragm and the diaphragm includes outwardly directed central recess in its end wall with an internal rib extending into the recess and which mates with the pin groove to retain the pin in position against the diaphragm.
Other forms of pump chamber are also contemplated. For example, as an alternative to one or more collapsible pump chambers, the chamber or chambers may comprise one or more cylinders along each of which a piston is advanced by operation of an actuator lever. Thus, as the piston is advanced along its respective cylinder, medicament is displaced out of the cylinder through an associated fluid outlet. Upon release of the lever, the piston is retracted along its cylinder, such as under the returning force of a spring, and the resulting negative pressure within the cylinder enables the cylinder to be refilled with medicament drawn in via the fluid inlet ready to deliver the next dose. Advantageously, the trailing end of the piston member carries a button, pin or the like which is pressed by the actuator lever to advance the piston. The piston may include one or more lip seals for providing a seal with the cylinder wall to prevent leakage of medicament and ensure the medicament is discharged via the outlet(s) to the nozzle(s).
Preferably the longitudinal axis of the pump cylinder lies transverse to the longitudinal axis of the applicator body (or cartridge), effectively providing a horizontal actuation with respect to the applicator.
The pump assembly may include one or more outlet valves for sealing the fluid outlet from the or each pump chamber to the nozzle(s) under negative pressure within the respective pump chamber and opening the fluid outlet under positive pressure within the respective pump chamber to allow discharge of medicament to the nozzle(s). Having such outlet valve(s) helps avoid any deterioration in the medicament within the pump chamber, substantially preventing medicament that has been discharged to the nozzle(s) from being returned to the pump chamber and keeping the pump chamber airless.
While various forms of valve may be employed, the outlet valve or valves may advantageously comprise a resilient, preferably elastomeric, material, permitting outward deformation of the material away from the or each outlet during application of a discharging force on the pump chamber to enable medicament to pass from the pump chamber(s) to the nozzles. In one arrangement, when the pump chamber is a collapsible chamber, the outlet valve(s) and collapsible chamber may be provided as an integral unit. Indeed, the inlet valve, collapsible pump chamber and outlet valve(s) may comprise a single, integral elastomeric profile, such as one in which the inlet valve is a flap valve formed by punching a flap or the like on a substantially flat portion of the elastomeric profile and the pump chamber and outlet valve(s) are formed on appropriately contoured portions of the profile. In another arrangement, the outlet valve may be the same as or substantially similar to the inlet valve, for example, the outlet valve may also comprise a unitary valve moulding comprising both a valve member and spring as hereinbefore described. With a valve of this type, any anchor portion may be captured between a moulding that comprises part of the pump assembly and another moulding that provides the fluid pathway to the nozzle.
The material of the chamber walls, or a lining thereof, should ideally be one that does not degrade under prolonged contact with the medicament, thereby ensuring that the medicament does not become contaminated with by-products of degradation and also ensuring that the applicator can be re-used over an extended period of time. Preferred elastomeric materials for the collapsible pump option include silicone, fluoroelastomer or thermoplastic elastomer.
The actuator of the applicator according to the invention may be disposed towards the rear of the inclined applicator face, with the pump chamber(s) of the pump assembly interposed between the nozzle(s) and the actuator. When the actuator is located on a side portion of the applicator that in use, i.e. in a dispensing position, faces away from the scalp, as well as the actuator being readily accessible, facing away from the scalp during dispensing and massaging, the actuator is operated by movement substantially in the dispensing direction. When the actuator, pump chamber(s) and dispensing nozzles are substantially aligned in this way, this helps lessen the force required to operate the actuator to dispense medicament. Not only is this is particularly advantageous for those users who suffer, for example, from stiff or painful joints since the effort required for dispensing medication is reduced, it makes the applicator suitable for one-handed operation.
For applicators comprising a single nozzle and an application face substantially continuous with each other, the actuator may be disposed beneath and substantially in line with the nozzle. Where an application face is provided beneath the nozzle, the actuator may be better disposed on the opposite side of the applicator to the application face, to avoid inadvertent operation of the actuator during spreading of medicament by the application face.
The actuator preferably comprises a plunger mechanism for positively displacing medicament from the or each pump chamber. For example, the actuator may comprise a plunger and a button, whereby the button is pressed to advance the plunger and displace medicament from the pump chamber. More preferably, instead of a button, the actuator may comprise plunger and a lever arm, the lever arm providing a mechanical advantage. The lever arm is advantageously inclined from a fulcrum away from the applicator body, such that the plunger acts upon the pump chamber(s) when the lever arm and applicator body are squeezed together. The lever arm may be substantially straight or gently curved, or may be angular, for example L-shaped, with a first leg extending outwards, substantially normal or inclined with respect to the longitudinal axis of the applicator body, and a second leg depending from the first leg (i.e. depending away from the applicator head) substantially parallel with the applicator body. In the latter arrangement, actuation may be performed either by pushing down on the first leg of the lever arm or by squeezing the second leg with the pump body.
Since the size of the area that may require treatment can differ significantly from patient to patient, as can the specific location on the scalp, the applicator may be adapted accordingly. Thus for patients suffering only a mild scalp condition and requiring application of medicament to a relatively small area of scalp, the applicator may comprise an applicator head having a single nozzle. Such a single nozzle applicator head is also useful when the medicament is required to be applied to awkward or hard to reach areas of the scalp, such as behind the ears, or along the hairline. Whilst not being limited thereto, a single nozzle applicator may be used to deliver a dose of medicament in an amount, for example, in the region of 0.05 to 0.1 g per actuation. Smaller or larger doses can be achieved, such as by appropriate adjustments to the volume of the pump chamber.
For patients suffering from a more severe scalp condition, and hence requiring application of medicament over a wider area, the applicator preferably comprises an applicator head having a plurality of spaced apart nozzles, for example with from two to six nozzles, preferably from two to four nozzles, and most preferably three nozzles. The Applicant has found that three nozzles represent a convenient balance for penetrating the hair and spreading the medicament across a wider area, but also three nozzles are preferred due to the stability achieved; three nozzles are always able to be in contact with the scalp. Again, whilst not being limited thereto, a three-nozzle applicator may be used to deliver a dose three times the dose achieved by an equivalent single nozzle applicator, for example in the region of 0.15 to 0.3 g per actuation. As above, adjustments of the pump chamber volume may be utilised to determine the precise dosage.
The face of the applicator head in the case of a multi-nozzle applicator may have a face area roughly similar to the area of scalp to be covered by the medicament dose delivered. For example, a three-nozzle applicator head may have a face area three times larger than the face area of a single-nozzle applicator.
Of course, a patient's condition may change over a period of time such that it may improve from a serious condition to a mild condition, or vice versa, or a patient may have several areas to treat which are appropriate for single and multiple nozzle treatment. In this regard, rather than providing the applicator with a single user specific applicator head, the applicator may comprise a plurality of interchangeable applicator heads each having a different nozzle configuration. Thus, for example, the applicator may be provided with interchangeable single and triple nozzle applicator heads.
Such interchangeable applicator heads may be provided with an integral pump assembly to allow a user more easily to change the applicator from, say, a single nozzle applicator to a multi-nozzle applicator. As will be appreciated, different fluid outlet arrangements may be required according to the nozzle configuration. For example, while the pump assembly for a multi-nozzle applicator may comprise a single outlet from a single pump chamber with fluid passageways branching further upstream of the pump chamber according to the number of nozzles provided, the pump chamber itself may alternatively have a plurality of outlets. Alternatively, more than one pump chamber may be provided, each chamber delivering medicament to a respective dispensing nozzle or group of nozzles under operation of the actuator.
Instead of providing interchangeable heads to cater for different required dosages, the applicator head of the applicator preferably comprises a plurality of dispensing nozzles and a nozzle selector mechanism operable in a first mode to dispense medicament from all the nozzles and in a second mode to dispense medicament from one of the nozzles only. In this way, the user is able to select whether to dispense medicament from a single nozzle, such as when applying to only a small area of scalp, or to all of the nozzles, such as when the area to be treated is more extensive.
It has been found that an applicator head comprising three nozzles creates an effective balance between scalp coverage and hair penetration ability, together with a significant volume of medicament, typically a drop, dispensed per nozzle. Thus, the nozzle selector mechanism in one mode preferably dispenses medicament from a single nozzle and in another mode it dispenses medicament not only from the single nozzle of the other mode, but two additional nozzles. Of course, it will be appreciated that when more than three nozzles in total are provided, the dispensing arrangements adapted accordingly.
Advantageously, the nozzle that dispenses medicament when the selector is set in its second mode, that is the mode for single nozzle dispensing, projects beyond the other nozzles. In other words, the nozzle of the single dispensing nozzle is preferably longer than the other dispensing nozzles. Thus a user is able not only to identify the operative nozzle easily when dispensing from a single nozzle, but is able to direct that nozzle to the scalp area being treated and massage only that nozzle on the scalp. It is therefore possible to avoid the other (inactive) nozzles also being rubbed against the scalp, potentially aggravating the scalp where no problem exists. The single nozzle tip preferably projects by 10 mm to 15 mm beyond the tips of the other nozzles.
In an applicator that can be switched between single and multiple nozzle dispensing modes, the pump assembly may advantageously comprise more than one pump chamber and the nozzle selector mechanism is adapted to discharge medicament from all pump chambers when in the first mode and from a single pump chamber when in the second mode upon operation of the actuator. By having more than one pump chamber and determining whether to discharge medicament from one or all of the chambers, it is possible also to vary the dose of medicament that is dispensed. For example, the dose discharged from all chambers simultaneously will typically be a multiple of the dose discharged from a single pump chamber only. In this way, the nozzle selector mechanism also dictates the dose dispensed.
In one arrangement, the applicator comprises a pump assembly having two pump chambers, one chamber having a capacity adapted for discharging a dose of medicament to a single nozzle and the other chamber having a capacity greater than the capacity of the one chamber for discharging substantially the same dose of medicament to each of two or more further nozzles. Thus, in the case of an applicator with three nozzles, the capacity of the other chamber is substantially twice that of the first chamber.
Conveniently, a nozzle selector mechanism selectively operable on one or all chambers may be integrated with the actuator. For example, the nozzle selector may be integrated with a plunger of the actuator. In a preferred arrangement, the plunger comprises a rotatable element that is selectively operable on one pump chamber or all pump chambers according to the rotation position of the plunger. More preferably, the plunger can also be rotated to a further position in which the plunger is inoperable on all of the pump chambers, effectively providing a locked position of the applicator in which operation of the actuator results in no medicament being dispensed.
When the applicator comprises two (or more than two, though two is the preferred number) pump chambers each in the form of rolling diaphragms with associated chamber pins projecting out from the diaphragm casings, the rotatable plunger may comprise a plunger body, an actuator rod extending from the rear of the plunger body, and three or more apertures in a front face of the plunger body, the apertures spaced in such a way that when rotated to a first plunger position the plunger face advances all chamber pins upon actuation of the actuator rod thereby to discharge medicament from all pump chambers, when rotated to a second plunger position the plunger face advances only the chamber pin associated with the pump chamber that discharges to a single nozzle (the other chamber pin being received in an aperture so that it is not advanced), and when rotated to a third plunger position the plunger face contacts none of the chamber pins (all chamber pins being received in respective apertures) so that no medicament is discharged upon actuation.
A dial is preferably provided to the rear of the plunger body for permitting a user to select the required dispensing mode, the dial having a central aperture through which the plunger or actuator rod extends. The actuator rod preferably has an asymmetric cross-section and the central dial aperture has a corresponding cross-section so that when the dial is rotated to select a particular mode the actuator rod and hence the plunger body are simultaneously rotated.
The dial may also be provided with a tab that extends for a short distance beyond the outer dial circumference for engaging with a complementary recess on the underside of the actuation lever when the dial ring is in the third, non-dispensing (locked) position.
Advantageously, the switching mechanism further comprises an insert interposed between the dial and plunger body, the insert having a plurality of internal projections acting as keys that co-operate with external projections on the plunger body to permit reciprocating (back and forth) movement of the plunger body only when the plunger body is in pumping (single and multiple nozzle dispensing) or locked positions.
Of course, other arrangements for varying the dose dispensed by the applicator may be provided and will now be described. For instance, the applicator may be provided with a separate dose selector mechanism for permitting variation in the amount of medicament dispensed upon operation of the actuator. When the applicator comprises both a nozzle selector mechanism and a dose selector mechanism, the volume of medicament dispensed from all the nozzles may again be a multiple of the volume of medicament dispensed from a single nozzle. Thus the combination of nozzle and dose selector mechanisms offers another means of changing the applicator from a single nozzle discharge to a multiple nozzle discharge, and changing the dose of medicament that is dispensed.
When the dose selector mechanism is separately operable from the nozzle selector mechanism, a user may, for example, initially operate the nozzle selector mechanism to select either single or multiple nozzle discharge, then operate the dose selector mechanism to select the dose to be discharged from the selected nozzle(s).
The dose selector mechanism may operate by altering the degree of actuation of the actuator between first and second operating modes in order to alter the volume of medicament displaced from the pump chamber. For example, when it is desired to dispense medicament from a single nozzle only, the dose selector mechanism may be set to limit the degree of movement of the actuator and hence the volume of medicament displaced from the pump chamber, whereas when medicament is to be dispensed through all nozzles, the dose selector mechanism is set such that movement of the actuator, such as a lever or button thereof, is unrestricted. It will be appreciated that this arrangement may equally be incorporated on applicators that have fixed applicator heads (for example, single nozzle or triple nozzle heads, including heads that incorporate an application face for spreading medicament), and on applicators with interchangeable heads.
The actuator limiting device may take the form of a switch, such as a lever switch or dial switch, which in a first position permits full actuation and in a second position permits only limited actuation. The switch may be carried on the actuator itself or adjacent thereto. For example, when the actuator comprises a lever, the switch may comprise a lever switch carried on the lever itself or on the body of the applicator. In the latter case, the switch may be adapted to move from a first position in which there is no obstruction of the lever to a second position in which the switch partially obstructs movement of the lever towards the applicator body.
The actuator, whether a button or a lever mechanism or another, may include a spring or equivalent, for returning the actuator to a start position ready for the next actuation. If a switch is present to limit the actuator, then the spring will return the actuator to the appropriate position set by the switch.
The applicator may further comprise an actuator lock for guarding against inadvertent dispensing of medicament. Such a lock is usefully engaged when the applicator is packed in a bag, for example for travel, and is especially useful to prevent accidental movement of a lever arm.
The actuator lock may be in the form of a switch which is moveable, such as by sliding or rotation, between a first position in which movement of the actuator, such as a lever arm, is substantially prevented and a second position in which the lever arm is free to pivot. The switch may be located on the applicator body or head, such as on a head assembly comprising the applicator head, pump assembly and actuator, adjacent the free end of the lever arm, for example between the lever arm and body, or on the lever arm. Insignia on the switch, or on the applicator body, head or lever arm adjacent the switch, or any combinations thereof may be provided to indicate the locked and unlocked positions.
In one arrangement, the actuator lock may be integral with the switch that comprises the movement limiting device of the dose selector. In this way, a user can select one of three switch positions, (i) to prevent any movement of the actuator, (ii) to limit the extent of movement of the actuator for dispensing a reduced dose of medicament or (iii) to permit unrestricted movement of the actuator for dispensing the maximum dose of medicament.
The aforementioned actuator locks offer an alternative solution to the rotatable plunger option hereinbefore described, in which the plunger may be rotated to a position where there is no interaction with the or each pump chamber on actuation of the plunger.
In another variation of an applicator that has a plurality of dispensing nozzles and a nozzle selector mechanism for selecting single or multi-nozzle dispensing, the pump assembly may comprise a unitary chamber, such as in the form of a cylinder, having a first fluid outlet at a distal end thereof for discharging medicament to one of the nozzles and a second fluid outlet at an intermediate position along the cylinder for discharging medicament to the remaining nozzles, wherein in a first operating mode the first and second outlet are open to the chamber such that medicament may be discharged from both first and second fluid outlets and in a second operating mode of the second fluid outlet is blocked by the piston in the cylinder such that medicament may be discharged from the first fluid outlet only.
In such an arrangement, the nozzle selector mechanism may involve advancing an actuator lever from a first position in which the piston is fully retracted to allow a complete discharge of medicament in the cylinder through both outlets to a second position in which the piston is partially advanced to a position in which the which the second fluid outlet is blocked by the piston, at which position the cylinder contains a reduced volume of medicament ready for discharging to a single nozzle. Thus the nozzle selection also automatically selects the dose. In switching from multiple nozzle to single nozzle dispensing, an amount of medicament will be dispensed as the piston is advanced to the second position. This “unwanted” medicament can simply be wiped from the nozzle outlets, and at the next and subsequent operation of the actuator, the correct dose is dispensed from one nozzle only.
In another arrangement, the dose selector mechanism comprises a nozzle shut-off (lock-out) valve for preventing fluid flow to all but a single nozzle and a sliding switch on a lever of the actuator mechanism for limiting the degree of permitted movement (rotation) of the lever. In operation, when dispensing is required from a single nozzle only, the lock-out valve is activated and the actuator switch slid up towards the fulcrum to reduce the travel of the lever and hence the distance by which the piston can be advanced.
In a further alternative arrangement, instead of providing a switch on the actuator lever to limit its movement, a switch may be provided on the applicator body or head which can be moved from a first position in which the actuation lever is permitted movement to displace a first, predetermined dose of medicament to a second position in which the switch limits the movement of the actuation lever to displace a second, smaller, predetermined dose of medicament. The switch effectively acts as a wedge between the lever and applicator body or head to control the degree of rotation of the actuator lever. In this arrangement, it is desirable that the applicator further includes a lock-out valve for preventing discharge of medicament to all but one of the dispensing nozzles. Thus, for single nozzle operation, the body switch is slid to its second position and the lock-out valve activated; in this way, a smaller dose may be dispensed from the applicator. Most preferably, the dose dispensed from the single nozzle will be proportionate to the total number of nozzles on the applicator. For a three nozzle applicator, the dose dispensed from the single nozzle will be one-third of that dispensed when all three nozzles are open.
Of course, there are many other arrangements that permit switching between single and multiple nozzle dispensing and indeed preventing dispensing altogether. For example, instead of a single lock-out valve that prevents medicament flow to all but one of the nozzles, an alternative arrangement may comprise multiple lock-out valves operable to close off flow to some or all nozzles. In the latter case, the valves may be provided on an integrated valve switch, whereby movement of the valve switch in one direction sequentially closes each valve. Thus in one extreme position all valves are closed, in the opposite extreme position all valves are open, and in an intermediate position at least one valve is open and another valve is closed. Such an integrated valve switch may be linked to the actuation lever, whereby the position of the lever as determined by the dose selector sets both the dose dispensed (as determined by the extent of movement permissible) and the number of nozzles effectively closed (as determined by the position of the valve switch). Also, as hereinbefore described, the applicator cover for shielding the application face and nozzle when the applicator is not in use may include an actuator lock in the form of an arm or the like that acts as a wedge behind the actuator lever to prevent movement thereof.
In another example, the actuation lever is simply adapted to provide audible or tactile feedback to a user. Thus, as the lever is squeezed towards the applicator body, sequential contact may be made between the lever and a series of projections to produce a sound, usually a “click”, indicating the dose dispensed. Thus at the first “click”, the user will know that a first dose has been dispensed, if the lever is advanced further a second “click” is heard indicating that a dose twice the amount of the first dose has been dispensed, and at the third “click” a dose three times the amount of the first dose has been dispensed, etc. Moreover, if a separate lock out valve is provided, such as one that closes two out of three nozzles, a user may activate the lock out valve and dispense one, two or three doses from a single nozzle corresponding to the number of clicks. Such an arrangement does of course rely on close attention by a user in order to dispense the desired dosage.
In addition to the present invention residing in an applicator for self-administration of medicament as hereinbefore described, the present invention further resides in a method of delivering semi-solid medicament to the scalp or other body area, said method comprising charging the medicament to an applicator body of an applicator, the applicator further comprising an applicator head fixed relative to the applicator body and having one or more elongate dispensing nozzles for penetrating the hair and contacting the scalp, a pump assembly comprising at least one pump chamber having an inlet for receiving a dose of medicament from the applicator body and one or more outlets for discharging medicament to the or each dispensing nozzle and an actuator operable on the or each pump chamber for pumping the dose of medicament in the chamber through the or each outlet, priming the applicator by operating the actuator to transfer medicament from the applicator body to the pump chamber and the or each nozzle, and thereafter delivering medicament by bringing the or each nozzle into contact with the scalp or other body area and operating the actuator to pump a dose of medicament from the chamber through the nozzle onto the scalp or other body area.
As will be appreciated, the charging and priming steps are required only at the outset prior to the first delivery of medicament to the patient's scalp or body area from a new medicament supply. Once charged and primed, the applicator may then be used to deliver further doses of medicament simply by operation of the actuator.
The step of charging medicament to the applicator preferably comprises inserting a dispensing end of a cartridge charged with medicament into a cartridge port on the applicator which cartridge port is in fluid communication with the inlet to the pump chamber.
Additionally, the present invention further resides in an applicator system characterised by an applicator as hereinbefore described having a cartridge port for receiving a dispensing end of a cartridge, the port being in fluid communication with the or each inlet to a respective pump chamber of the pump assembly, and a cartridge charged with medicament.
The present invention also embraces a dispenser system for semi-solid preparations, that is preparations that have properties intermediate solids and liquids, including but not limited to gels, ointments, creams and the like. In particular, the invention may also be expressed in terms of a system for dispensing a semi-solid preparation comprising:
As will be understood, by means of the aforementioned dispensing system, as the stopper of the dispensing head is inserted into the cartridge nozzle as would occur on assembly of the two components, air in the nozzle above the preparation fill line is purged through the vent and flows freely through the passage, including through the constricted section, prior to displacement of any preparation. Thus the purging of air in this way on assembly of the cartridge and dispensing head provides for efficient dispensing thereafter. Specifically, the need for priming the resulting assembly is substantially avoided or at least significantly reduced. Moreover, it is possible to assemble the system without significant loss of preparation from the cartridge, since the constricted passage effectively ensures that displaced preparation is mostly kept within the cartridge by expansion of the cartridge volume as the plunger is forced back. The presence of the constricted passage means that only a relatively small volume of preparation is capable of being vented from the cartridge.
Cartridges of the type described are typically subjected to automated filling processes but manufacturing tolerances in preparation density, variation in filling line and part size all may affect the resulting fill level of preparation in the cartridge. As a result, the volume of air in the cartridge nozzle above the fill level which is required to be displaced before preparation can flow into the dispensing head may be subject to wide variation. Accordingly, the stopper preferably has a length such that when fully inserted within the cartridge nozzle its leading end projects beyond a minimum fill level of the cartridge. In this way, the stopper ensures that on assembly air above the fill line is substantially displaced together with a volume of preparation. In a particularly preferred arrangement, the stopper extends substantially along the full length of the cartridge nozzle when fully inserted.
In practice, the volume of preparation displaced will depend on the actual fill level, but the capacity of the passage, at least that part of the passage that is before (upstream of) the constricted section is determined to accommodate a relatively small volume of preparation, preferably a volume that is less than the total volume of preparation that would be displaced by the stopper if the cartridge were filled only to the minimum fill level. The capacity of the passage, including the chamber where provided, is preferably more than about 0.5 cm3, that being the typical difference in volume between minimum and maximum fill levels, and hence the approximate maximum volume of air that will be displaced. In a dispenser having a pump chamber for dispensing doses of preparation of approximately 0.05 cm3, such a passage capacity means that at least 10 pumps of the dispenser may be avoided in a priming operation.
Preferably, the inlet valve is provided within the stopper bore, for example, there may be a valve seat projecting into the bore from the inner bore wall against which a valve member rests to close the valve. The valve seat preferably comprises an inclined surface and the valve closing member preferably comprises a ball. The inlet valve is preferably spring loaded, and the spring component which may be integral with or separate from the valve closing member, such as the ball, is preferably also accommodated within the stopper bore.
As will be appreciated, it is important that those components of the dispensing system that come into contact with the preparation are made of a material compatible with the preparation. In this way, contamination of the preparation may be avoided as well as any deterioration of the dispenser parts. This is especially important In relation to the valve, since any incompatibility with the valve closing member or spring could result in failure of the valve and leakage of the preparation from the dispenser. Accordingly, the ball is preferably a metal or plastics ball, for example made of low density polyethylene (LDPE) or fluorocarbon elastomer (FKM rubber), and the spring may also be of metal or plastics, LDPE being especially preferred. Where the ball is spherical and made of moulded plastic, it may be necessary to post-process the ball after moulding to remove any imperfections around the mould lines that might otherwise compromise the integrity of the ball. Alternatively, the ball may be moulded with an integral peg for the spring and in which case, the need to post-process the spherical surface of the ball can be avoided. Further preferred details regarding the valve are provided herein elsewhere, it being appreciated that those details and the details above are equally applicable to the dispenser system and the pump applicator as described in accordance with the various aspects of the invention.
In a preferred arrangement, the vent is located adjacent the inlet valve. By such means, the bore may be substantially fully charged with preparation upstream of the inlet valve as the stopper is advanced into the cartridge nozzle. More preferably, the bore contains an inner tube of restricted diameter and length (that is a diameter and length less than the diameter and length of the bore) extending from the inlet valve. For example, the inner tube may extend into the bore from the valve seat. Most preferably, the inner tube extends into the bore beyond the position of the vent, but terminates substantially short of the end of the stopper, preferably terminating short of the midpoint of stopper. When the dispenser head and cartridge are assembled, the restricted diameter of the inner tube means that preparation displaced by the stopper flows along the bore as far as the inner tube whereupon the preparation is forced around the outside of inner tube to the vent and passage beyond. In other words, the inner tube acts in the manner of a straw.
The length of the inner tube is desirably such as to have only a small volume so that after assembly of the cartridge and dispenser head, the first actuation of the dispenser (such as by pumping) results in any residual air being purged from the inner tube and preparation being sucked into the inner tube up to the inlet valve. In this way, the valve closing member, typically a ball, will be immediately wetted by the preparation giving an improved seal and thereby making priming of the dispenser more efficient.
Preferably the air and preparation is vented to a first passage section permitting free flow of vented air and preparation followed by a second section which is constricted relative to the first section permitting free flow of air but providing resistance to the flow of preparation and thereby creating back pressure when preparation flows into it. The back pressure results in reverse movement of the plunger in the cartridge to accommodate further displaced preparation.
The passage may comprise a continuous space created between the stopper and a dispensing head manifold, which together preferably define the cartridge port, or may comprise one or more channels between the stopper and manifold. The passage of constricted section may, for example, be provided in the form of one or more channels of smaller cross-section than in the first section, more preferably taking the form of a complementary threaded section between the stopper and manifold, effectively creating an elongate helical channel. The continuous change in direction of the passage provided by the helical channel creates the constriction that resists the flow of the preparation and gives rise to back pressure as preparation is forced along the channel.
In a preferred arrangement, the stopper may comprise a double-walled member wherein the inner wall provides the central bore through which preparation passes from the cartridge to the dispenser head, such as via an inner tube in the bore as hereinbefore described, and the outwardly directed surface of the outer wall seals against the inner wall of the cartridge nozzle, for example, by means of a lip seal or the like. The gap between the inner and outer stopper walls creates a substantially U-shaped cylindrical channel, closed at the front end to force preparation into the central bore as the stopper is inserted into the cartridge nozzle. In this arrangement, the vent is provided through the inner wall of the stopper, whereby air and preparation displaced by advancement of the stopper in the cartridge nozzle are initially forced along the bore towards the vent before exiting the vent for the passage.
The passage is most conveniently provided by a gap or space between the stopper and manifold. For example, the channel of a double-walled stopper may be adapted to receive and accommodate a tubular portion of the dispenser head manifold, and the tubular portion and cylindrical channel are dimensioned relative to each other such as to create the passage therebetween through which air and preparation is forced via the vent. For example, the passage follows a path initially down along the outwardly facing surface of the inner stopper wall, along the base of the channel and up along the inwardly facing surface of the outer stopper wall. Advantageously, the constricted section of the passage is created by complementary threaded sections on the inwardly directed face of the outer stopper wall and outwardly directed face of the manifold tubular portion, preferably adjacent the open end of the U-shaped channel.
Advantageously, the dispensing head further includes a chamber into which displaced air may be contained, such a chamber is preferably provided downstream of the constricted passage, such as at the end of the aforementioned threaded section. The chamber is preferably sealed by the cartridge nozzle when the cartridge is assembled with the dispensing head. In this way, the preparation within the dispenser is effectively contained within a sealed system and any loss of efficacy of the preparation due to oxidation is substantially avoided. In a preferred arrangement, the manifold may include a continuous wall depending into the chamber which wall seals against the nozzle when the cartridge is in its fully inserted position. The manifold sealing wall is preferably concentric with the tubular portion that extends into the channel of the double-walled stopper.
The manifold may additionally include connecting features for securing the cartridge to the dispensing head, for example having a threaded portion for screwing the dispenser head on to a complementary threaded portion on the cartridge, preferably around the base of the cartridge nozzle. Preferably the manifold and cartridge are provided with a one-way lock mechanism permitting assembly of the dispenser head and cartridge but preventing their separation once assembled. For example, the manifold may include one or more, preferably an opposing pair, of head locking clips that ride over engagement ribs on the cartridge (such as are provided on an outer ring, concentric with the nozzle), when the cartridge is screwed on to the dispenser head, but act as a barrier to the ribs when an attempt is made to unscrew the assembly.
When the manifold forms part of an applicator head as hereinbefore described, it may incorporate the pump chamber of the pump assembly. Similarly, the manifold may house an outlet valve of the pump assembly.
It will be understood that the dispensing system according to this further aspect of the invention may be incorporated in the applicators as hereinbefore described, but are not limited to use in such applicators. In particular, the dispensing system may be deployed with any manner of dispensing heads, irrespective of whether the preparation is dispensed from a nozzle or from other forms of openings in the dispenser head, and irrespective of whether the dispenser head is adapted to deliver a dosed volume of preparation, such as from a pump chamber, or otherwise. Of course, the dispensing system of the present invention is especially suitable for use in the applicators according the other aspects of the invention and it should be understood that the dispensing system according to this further aspect may comprise some or all of the essential, optional and preferred features of the applicators set forth herein. Equally, the applicators according to the other aspects of the invention may comprise some or all of the essential, optional and preferred features of the dispensing system.
For the avoidance of doubt, the term semi-solid preparation used herein in relation to the dispensing system is intended to embrace both medicated and non-medicated preparations, that can flow or be extruded or spread, including but not limited to gels, creams, ointments and the like.
The invention will now be described by way of example only, with reference to the following drawings in which:
a to 1d are views of a single nozzle scalp applicator with cartridge in accordance with a first aspect of the invention;
a to 3e are views of a triple nozzle scalp applicator with cartridge in accordance with another aspect of the invention;
a to 5c are views of a switchable applicator with cap;
a to 6c are views of a cartridge with cap for use with the applicators according to the invention;
a to 7c are views of the cartridge of
a to 15c show respectively the locked position, single nozzle pump position and triple nozzle pump position of the switching mechanism of
a to 17c are cross-sections through the plunger body and insert of the switching mechanism of
a and 18b are views of an alternative single nozzle applicator for scalp and other body area application;
a and 26b are partial cross-sections of a fully disposable applicator showing first and second lever actuator positions;
a to 27d are perspective views of alternative valves for use in an applicator according to the invention;
a and 28b are schematic partial cross-sections through a head assembly and cartridge illustrating a first priming arrangement;
a and 29b are schematic partial cross-sections through a head assembly and cartridge illustrating an alternative priming arrangement;
a to 30c are schematic cross-sections through a cartridge with cartridge cap for use in a further priming arrangement;
a to 31c are perspective views of alternative covers for use with a single nozzle applicator according to the invention;
a to 32d are cross-section views of a further alternative applicator incorporating a dispenser system according to another aspect of the invention;
a to 33d illustrate the assembly sequence of the applicator/dispenser head and cartridge of the applicator of
In
A single nozzle 40 comprising a nozzle stem 42 terminating in nozzle tip 44 of softer material than the stem projects from an inclined applicator face 16 on the applicator head 14. The nozzle stem 42 tapers outwards where it joins the applicator face 16 to provide strength and a smooth contour for ease of cleaning. The nozzle tip 44 has a pair of opposite side ports 45 through which medicament is dispensed to the scalp.
The applicator 10 includes an actuator 30 in the form of lever arm 32 and actuator rod 39 which can be pushed in by the lever arm 32 to press a plunger 34 (not visible) within the applicator body 12 against a pump chamber 50 (not visible) of the pump assembly. The applicator 10 has a dial 70 with a tab 72 which can interlock with a recess on the rear side of the lever arm 32 at its distal end for preventing accidental actuation such as during storage or transport of the applicator. The dial 70 is rotatable about a central axis from the locked position to an unlocked position as shown in
a to 3e show an alternative applicator 10 having an enlarged applicator head 14 as compared to the applicator of
The applicator 10 also has a lever arm 32 and actuator rod 39 which can be pushed in by the lever arm 32 to press a plunger 34 (not visible) within the applicator body 12 against a pump chamber 50 (not visible) of the pump assembly. Similarly, there is a dial 70 with a tab 72 for interlocking with a recess on the rear side of the lever arm 32 to guard against accidental dispensing of medicament. The dial 70 is rotatable about a central axis from the locked position as shown in
a to 5c show a switchable applicator 10 fitted with a cap 18 to protect the nozzles 40, 40a of the applicator when not in use, such as for storage or transportation. The cap 18 has a thickened rim (not shown) that is caught and held by a corresponding recess (not shown) around the perimeter of the applicator head 14 to retain the cap 18 in place. The cap 18 is made of a flexible material to enable the cap to be prised away from the applicator head 14 when preparing the applicator 10 for use. A series of ribs 19 on opposite sides of the cap 18 provide a gripping function to assist a user when removing of the cap.
a to 6c show a cartridge 20 for use in all variations of scalp applicator 10, including those of
a to 7c correspond to the
An outlet 66 for medicament discharged from the diaphragm 51 visible in
As shown in
The pump manifold 64 has dual inlets 63, first and second rolling diaphragm chambers 51 (not visible) each having an associated casing 52 and chamber pin 55. The chamber that feeds through to the single nozzle 40a has half the capacity of the other chamber that feeds through to the remaining two nozzles 40, consequently the casings 52 are also of different sizes. However the respective chamber pins 55 project to the same plane which lies parallel to the front face 38 of plunger body 36.
A rotatable plunger body 36 is provided with spaced apart apertures 37 on its front face 38 which apertures 37 can accommodate one or both the chamber pins 55 according the mode selected when the plunger body 36 is pushed in. An actuator rod 39 extends from the rotatable plunger body 36 and projects beyond the rear of the plunger body. The actuator rod 39 has an asymmetric cross-section that slots through a similarly shaped asymmetric aperture 74 in the dial 70. An insert 90 between the plunger body 36 and dial 70 has internal projections 92 that act to prevent the actuator rod 39 from being moved back and forth unless the plunger body 36 is in one of the correct positions.
As shown in
b shows the plunger body 36 in the single nozzle 40a dispensing position, whereby when the actuator rod 39 is pushed, one of the pump pins 55 goes into the aperture 37 in the plunger body 36 and the other pump pin 55 is pushed by the front face 38 of the plunger body 36, thereby discharging medicament from one pump chamber, notably the pump chamber that feeds the single nozzle 40a.
b shows the plunger body 36 in the triple nozzle dispensing position, whereby when the actuator rod 39 is pushed, both pump pins 55 are pushed by the front face 38 of the plunger body 36, thereby discharging medicament from both pump chambers 50 and resulting in medicament being dispensed from all three nozzles 40a, 40.
The various relative positions of the plunger body 36 and insert 90 that permit triple nozzle pumping, no pumping, and single nozzle pumping are shown sequentially in
a and 18b illustrate an alternative single nozzle applicator 100 for dual purpose use, namely for use in applying medicament to body areas as shown by the orientation of the applicator in
c shows an applicator similar to that of
A partial cross-section through the applicator head 114, pump assembly and actuator of the applicator of
The lever arm 132 pivots about a fulcrum within the applicator head 114 behind the nozzle 140, the arm extending away from the applicator body 112 beneath the nozzle 140 in the manner of a trigger.
Instead of a membrane pump as shown in
The angle of inclination and orientation of the application face with respect to the applicator body and the nozzle may be altered, as may the position of the actuation lever. A number of variations in the applicator configuration are exemplified in
For example,
In
The applicator of
In each of the illustrated variations of
In
a and 26b show partial cross-sections of a fully disposable applicator with head assembly 214 fitted to cartridge 220 in accordance with a further aspect of the invention. The cartridge port of the head assembly 214 includes a stopper 282 having a lip seal 284 that seals against the inner wall of the cartridge neck 222. The upper, discharging end of the cartridge neck 222 has an inwardly directed flange 224 which prevents the lip seal 284 from passing back over the flange and hence separation of the cartridge neck 222 from the head assembly 214 once the cartridge 220 has been inserted. The head assembly 214 includes an actuator including a horizontal force pump having a piston 260 provided with a lip seal 262 in sealing contact with the inner cylinder wall of the pump chamber 250. The trailing end of the piston 260 carries a button 255 that is acted upon by the lever arm 232 of the actuator driving the piston 260 along the cylinder against a resilient force provided by the spring 256.
a to 27d are perspective views of alternative valves for use in an applicator according to the invention, such as in the applicator as shown in
a and 28b are schematic cross-sections through a head assembly 214 and cartridge 220 illustrating a first priming arrangement in which air is bled out through the interface between the head assembly and cartridge. The head assembly 214 includes a stopper 282 attached to a cap 288, and a unitary valve moulding 310 of the type generally shown in
An alternative priming arrangement is shown in
Another priming arrangement is shown in
b shows the cartridge 220 fitted to the applicator head assembly 214 after the cap 226 has been removed. The assembled applicator still includes a volume of air at the neck of the cartridge that must be discharged before the applicator can dispense a medicament dose.
a to 31c are perspective views of alternative covers 370a, 370b, 370c for use with a single nozzle applicator. In
The cover of
Instead of shielding the actuator lever, the cover of
In
A chamber 610 is provided in the manifold 600 beyond the threaded section 604 and a wall 612 in the cartridge port 580 of the manifold seals against the upper end of the cartridge nozzle 522 so that air from the nozzle displaced by the stopper 582 is ultimately trapped in the chamber 610.
The dispensing head 514 of
a to 33d show the effect achieved by the stopper 582 when the applicator/dispenser head 514 is fitted into the cartridge nozzle 522 during assembly of the applicator of
The path taken by air and preparation displaced by the stopper 582 is shown in more detail in
A cartridge 520 with cap 524 for use with the dispenser head 514 shown
The cartridge 520 (shown with cap removed) together with the applicator/dispenser head 514 is illustrated in perspective view in
Many other variations are possible and while a number of examples have been chosen to illustrate the present invention, it will be apparent to those skilled in the art that various changes and modifications can be made herein without departing from the spirit and scope of the invention. Moreover, the applicator may be used to apply medicaments for any number of skin complaints affecting the scalp and other body areas, including for example dermatitis and eczema, as well as psoriasis. Combinations of features described hereinbefore, whether or not exemplified, are also regarded as falling within the scope of the invention. Thus, the foregoing description of the embodiments according to the present invention are provided for illustration only, and not for the purpose of limiting the invention.
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP2012/070705 | 10/18/2012 | WO | 00 | 4/17/2014 |
| Number | Date | Country | |
|---|---|---|---|
| 61549952 | Oct 2011 | US | |
| 61587907 | Jan 2012 | US | |
| 61654577 | Jun 2012 | US |
