GB2538285A

GB2538285A - A fluid delivery device

Info

Publication number: GB2538285A
Application number: GB1508272.0A
Authority: GB
Inventors: Henry Southby William; Allsop Paul
Original assignee: Consort Medical Ltd
Current assignee: Consort Medical Ltd
Priority date: 2015-05-14
Filing date: 2015-05-14
Publication date: 2016-11-16
Anticipated expiration: 2035-05-14
Also published as: GB201508272D0; GB2538285B

Abstract

A fluid dispensing device comprising a fluid reservoir container 11, a pump 3 and an actuator 4, wherein the fluid dispensing device is provided with an auditory indicator for signalling when the valve stem has been moved with respect to the fluid reservoir through a sufficient stroke length to pump a required quantity of fluid from the fluid reservoir into the delivery duct. The auditory indicator comprises a mechanical clicker 6. In use the actuator 4 and mechanical clicker 6 are pressed towards the fluid reservoir, causing downstands 53 to be pressed against face 21 and eventually deforming the inner ring 50 of the clicker relative to the outer ring 51, whereby flexible arm 54 rides over the inner annular ring 50 and makes an audible clicking noise.

Description

A Fluid Delivery Device The present disclosure relates to a fluid delivery device that comprises an auditory indicator for indicating to a user when the device has been actuated correctly. The disclosure finds particular application in the field of medical pump devices where the accurate administration of known quantities of fluids is desirable.

Background

Fluid delivery devices, such as pumps, are known in the art as being suitable for the dispensation of metered quantities of a fluid stored in a bulk supply, such as a fluid reservoir. For example, in the medical field pumps are used for dispensing metered quantities of medicaments for delivery by oral, nasal and sub-lingual pathways.

Such pumps work by utilising the stroking motion of a valve stem (also known as a piston core) to apply overpressure to fluid contained in a metering chamber of the pump so as to force the fluid out of the metering chamber, through the valve stem and into a delivery component, such as a nozzle head from where it can be dispensed to the user. The reciprocal stroking motion is also used to create suction forces on the return stroke that are used to refill the metering chamber for the next dose through, for example, a dip tube that communicates with the bulk supply of fluid.

In order to dispense the correct volume of fluid, and to ensure complete refilling of the metering chamber, it is important that the valve stem is fully depressed during the actuation of the fluid delivery device. However, it has been found that it is quite common for a user of pumps to stop depressing the valve stem before it has been depressed sufficiently. This problem is exacerbated in the case of pumps because they typically require a relative long stroke length in order to produce the necessary overpressures and suction forces. For example a stroke length of 6 to 8 mm is typical for a pump device. By comparison, a pressurised metered dose inhaler device that utilises a volatile propellant fluid for delivering the product on actuation has a typical stoke length of only 1 to 2 mm. The longer stroke length in the case of a pump allows a user more time to inadvertently stop the manual stroking action of the valve stem. The likelihood of this can be increased by the sensation that fluid will start to be dispensed to the user before the stroke has been completed.

For these reasons it would be desirable to provide means for helping a user to correctly actuate a fluid delivery device, in particular one in the form of a pump requiring a relatively long stroke length.

Summary of the Disclosure

According to the present disclosure there is provided a fluid dispensing device comprising a fluid reservoir, a pump and an actuator; the pump being mounted on the fluid reservoir and comprising a valve stem through which a fluid from the fluid reservoir is discharged on operation of the pump; the actuator being mounted on the valve stem of the pump and comprising a delivery duct, for receiving the fluid discharged from the valve stem of the pump, and an outlet orifice, for discharging said fluid; the actuator and valve stem being reciprocally movable with respect to the fluid reservoir so as to actuate the pump; wherein the fluid dispensing device is provided with an auditory indicator for signalling when the valve stem has been moved with respect to the fluid reservoir through a sufficient stroke length to pump a required quantity of fluid from the fluid reservoir into the delivery duct; wherein the auditory indicator comprises a mechanical clicker that is activated once the valve stem has moved through the sufficient stroke length.

The provision of the auditory indicator provides a clear and reliable indication to a user that the valve stem of the pump has been sufficiently depressed. In this way the complete dispensation of each dose of the fluid can be facilitated. In particular the use of an auditory indicator is beneficial compared to use of a purely tactile indicator since with a tactile indicator the user can confuse a tactile signal with the normal tactile sensations of operating the pump. However, the auditory indicator may be used in combination with a tactile indicator and, the auditory indicator may be configured to provide tactile feedback to the user as well as auditory feedback.

Advantageously, the provision of the auditory indicator helps to train a user how to correctly actuate the pump to receive the desired dosage of fluid since it teaches the user the correct degree of stroking of the valve stem and actuator required.

Preferably, the mechanical clicker is mounted to the valve stem, with no part of the mechanical clicker being mounted to the fluid reservoir or other part of the pump. This allows for the mechanical clicker to be contained solely within the confines of the actuator and also allows the mechanical clicker to be easily dismounted from the pump along with the actuator if desired. It also allows for the mechanical clicker to be provided as a unit with the actuator so that the unit can be fitted easily to a pre-existing fluid reservoir and pump assembly. In this way, the mechanical clicker is moved up and down with the valve stem of the pump during actuation. In addition, this arrangement has the advantage that the mechanical clicker is directly mounted to the valve stem without any intervening parts. This improves the accuracy, repeatability and predictability of the timing of the auditory signal vis-a-vis the valve stem movement.

Alternatively, the relative positions may be reversed such that the mechanical clicker is mounted to a static surface of the fluid delivery device and the actuator is moved to bring it into contact with the mechanical clicker.

On or immediately after activation of the mechanical clicker, the mechanical clicker may restrict the stroke length of the valve stem so as to prevent further downward movement of the valve stem. For example, this may be achieved by ensuring that two or more parts of the mechanical clicker bottom out against each other at the same time or shortly after the auditory signal is generated and that at least one of those parts is engaged against a static surface of the fluid dispensing device. Preferably, the two parts that bottom out against each other are the two parts whose mutual engagement also produces the auditory signal.

The mechanical clicker may comprise a first part that is engagable against a static surface of the fluid dispensing device during stroking of the valve stem and a second part that can be engaged by the first part to produce an auditory clicking sound. Preferably, the static surface comprises a leading face of a pump body of the pump, or, where the pump is mounted to the fluid reservoir by means of a ferrule, a leading face of the ferrule.

The auditory clicking sound is produced by mechanical contact between the first part and the second pad. Engagement between the first part and the second pad may produce elastic deformation of either or both of the first part or the second part. The auditory clicking sound may be at least in part produced by the initial contact between the first part and the second part. Preferably the auditory clicking sound at least in part includes sound produced by elastic deformation and/or recovery of the first part and/or second part after an initial contact.

Preferably, the first part and second part are compressed against one another to produce the auditory clicking sound.

In one embodiment the first part comprises an annular ring that is disposed about the valve stem and/or pump and is contactable against the static surface. The annular ring may be disposed concentrically to the valve stem. The plane of the annular ring may be perpendicular to a longitudinal axis of the valve stem in a rest position.

Preferably, the annular ring comprises one or more downstands that are contactable against the static surface. The one or more downstands may be arranged asymmetrically around the annular ring. For example there may be more downstands on one half of the annular ring compared to the other half. In one example the one or more downstands may be provided exclusively on one half of the annular ring. The precise angular location of the downstands around the circumference of the annular ring and/or the number of the downstands can be varied in order to fine tune the operation of the mechanical clicker. For example, an asymmetric arrangement of downstands can be used to impart a 'tilting' motion to the annular ring (so that the plane of the annular ring becomes non-perpendicular to the longitudinal axis of the valve stem) when it is engaged against and moved by the static surface of the fluid dispensing device into engagement with the second part. In this way the degree of interference contact between the annular ring and the second part can be varied by design.

The second part may comprise a flexible arm.

Preferably an annular ring and a flexible arm are used in combination as the first part and the second part, respectively, of the mechanical clicker. Preferably, the annular ring and flexible arm are formed integrally as, for example, a one piece molding.

Advantageously the first part and the second part (whether an annular ring and flexible arm or otherwise) which are compressed against one another may be formed as a single, unitary component. For example, the first and the second part may be formed as a single molded component. This reduces the number of separate components to be assembled and also improves the manufacturing tolerances of the auditory indicator thereby improving operation. This is because there is no potential variability in relative positioning of the first part and the second pad which might arise if the parts were formed separately and then assembled together.

More preferably the first part comprises an inner annular ring that is disposed about the valve stem and is contactable against the static surface and the second part comprises an outer annular ring from which a flexible arm extends, wherein the inner annular ring is joined to the outer annular ring by a plurality of legs, and preferably the plurality of legs are configured to reset the first part relative to the second part after each actuation of the fluid dispensing device. In this case, preferably the plurality of legs comprises an odd number of legs, more preferably three legs. Preferably the flexible arm is located diametrically opposite one of the plurality of legs. In this embodiment the inner annular ring may comprises one or more downstands, which may be as described above, and are contactable against the static surface, wherein the one or more downstands may be located only on one half of the inner annular ring, preferably that half nearest the flexible arm.

The mechanical clicker may further comprise a mounting part for mounting the first part and the second part to the actuator. The mounting part may comprise a socket for receiving a distal end of the valve stem.

The actuator may comprise a cup-shaped actuator body having a top wall and a dependent side wall skirt; wherein the dependent side wall skirt may be provided with a plurality of guiding ribs which can slidingly engage a surface of the pump or fluid reservoir to maintain axial alignment of the actuator relative to the valve stem. Maintaining the alignment of the actuator, and hence the mechanical clicker, relative to the valve stem is advantageous in helping to ensure that the first part and second part engage at the correct point of the actuation stroke and with a correct amount of interference contact to produce the required auditory signal.

The auditory indicator may be coupled to the actuator such that in the case of removal of the actuator from the pump and fluid reservoir the actuator and auditory indicator remain coupled together.

The pump may be a compression pump and the sufficient stroke length to pump a required quantity of fluid from the fluid reservoir into the delivery duct may be greater than 6 MM.

The present disclosure also extends to an actuator for a fluid dispensing device, the actuator comprising: a delivery duct, for receiving, in use, a fluid discharged from a valve stem of a pump; an outlet orifice, for discharging said fluid; and an auditory indicator for signalling when a valve stem coupled to the actuator has been moved through a sufficient stroke length; wherein the auditory indicator comprises a mechanical clicker that is activated once the valve stem has moved through the sufficient stroke length.

The fluid delivery device may be a pharmaceutical dispensing apparatus, such as, for example, a nasal, buccal, topical, aural or sub-lingual delivery device. A preferred use of the fluid delivery device is as pump device for delivering a pharmaceutical in a spray form. The term pharmaceutical, as used herein, is intended to encompass any pharmaceutical, compound, composition, medicament, agent or product which can be delivered or administered to a human being or animal, for example pharmaceuticals, drugs, biological and medicinal products. Examples include antiallergics, analgesics, bronchodilators, antihistamines, therapeutic proteins and peptides, antitussives, anginal preparations, antibiotics, anti-inflammatory preparations, hormones, migraine treatments, smoking cessation treatments, treatments for congestion, rhinitis, sinusitis and hay fever or sulfonamides, such as, for example, a vasoconstrictive amine, an enzyme, an alkaloid, or a steroid, including combinations of two or more thereof. In particular, examples include isoproterenol [alpha-(isopropylaminomethyl) protocatechuyl alcohol], phenylephrine, phenylpropanolamine, glucagon, adrenochrome, trypsin, epinephrine, ephedrine, narcotine, codeine, atropine, heparin, morphine, dihydromorphinone, ergotamine, scopolamine, methapyrilene, cyanocobalamin, terbutaline, rimiterol, salbutamol, ipratropium bromide and salbutamol, flunisolide, colchicine, pirbuterol, beclomethasone, orciprenaline, fentanyl, and diamorphine, streptomycin, penicillin, procaine penicillin, tetracycline, chlorotetracycline and hydroxytetracycline, adrenocorticotropic hormone and adrenocortical hormones, such as cortisone, hydrocortisone, hydrocortisone acetate and prednisolone, insulin, cromolyn sodium, and mometasone, including combinations of two or more thereof.

The pharmaceutical may be used as either the free base or as one or more salts conventional in the art, such as, for example, acetate, benzenesulphonate, benzoate, bircarbonate, bitartrate, bromide, calcium edetate, camsylate, carbonate, chloride, citrate, dihydrochloride, edetate, edisylate, estolate, esylate, fumarate, fluceptate, gluconate, glutamate, glycollylarsanilate, hexylresorcinate, hydrobromide, hydrochloride, hydroxynaphthoate, iodide, isethionate, lactate, lactobionate, malate, maleate, mandelate, mesylate, methylbromide, methylnitrate, methylsulphate, mucate, napsylate, nitrate, pamoate, (embonate), pantothenate, phosphate, diphosphate, polygalacturonate, salicylate, stearate, subacetate, succinate, sulphate, tannate, tartrate, and triethiodide, including combinations of two or more thereof. Cationic salts may also be used, for example the alkali metals, e.g. Na and K, and ammonium salts and salts of amines known in the art to be pharmaceutically acceptable, for example glycine, ethylene diamine, choline, diethanolamine, triethanolamine, octadecylamine, diethylamine, triethylamine, 1-amino-2-propanol-amino-2-(hydroxymethyl)propane-1,3-diol, and 1-(3,4-dihydroxypheny1)-2 isopropylaminoethanol.

The pharmaceutical may be provided in any suitable form for this purpose, for example as a solution or powder suspension in a solvent or carrier liquid, for example ethanol, or isopropyl alcohol.

The pharmaceutical may, for example, be salbutamol, beclomethasone, salmeterol, fluticasone, formoterol, terbutaline, sodium chromoglycate, budesonide, ciclesonide, fluticasone, triamcinolone acetonide and flunisolide, and physiologically acceptable salts (for example salbutamol sulphate, salmeterol xinafoate, fluticasone propionate, fluticasone furoate, beclomethasone dipropionate, and terbutaline sulphate), solvates and esters, including combinations of two or more thereof. Individual isomers such as, for example, R-salbutamol, may also be used. Other examples of suitable pharmaceuticals include cannabinoids, nicotine, sumatriptan and zolmitriptan.

As will be appreciated, the pharmaceutical may comprise of one or more active ingredients, and may optionally be provided together with a suitable carrier, for example a liquid carrier. One or more surfactants may be included if desired.

Alternatively, the fluid delivery device may be used for dispensing other fluids, for example cosmetics.

The fluid delivery device is preferably a multi-dose device intended to dispense multiple doses of fluid during its working life. Typically, the fluid delivery device will contain from 10 to 200 doses. Thus, the auditory indicator is configured in terms of, for example, the durability of its materials, to be operable from 10 to at least 200 times.

Rigid components of the fluid delivery device may be formed from, for example, from polyester, polypropylene, nylon, acetal or similar.

Brief Description of the Drawings

An embodiment of the present disclosure will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a perspective exploded view of a fluid dispensing device according to the present disclosure (with some parts sectioned to show hidden detail); Figure 2 is a perspective view of the fluid dispensing device of Figure 1; Figure 3 is a perspective exploded view of a mechanical clicker of the fluid dispensing device of Figure 1; Figure 4 is a plan view from beneath of the mechanical clicker of Figure 3 mounted within an actuator forming a sub-assembly of the fluid dispensing device of Figure 1; Figures 5a and 5b are perspective views of the sub-assembly of Figure 4 in, respectively, starting and actuated configurations; and Figures 6a to 6c are side elevations of a part of the fluid dispensing device of Figure 1 (with some parts sectioned to show hidden detail) showing the mechanical clicker and actuator sub-assembly in, respectively, starting, intermediate and actuated configurations.

Detailed Description

As shown in Figure 1, the fluid delivery device 1 of the illustrated embodiment comprises a fluid reservoir 2, a pump 3 and an actuator 4. The pump 3 is mounted on the fluid reservoir 2.

The fluid reservoir 2 is in the form of a cylindrical container 11 that defines an internal volume for storing a fluid to be dispensed and has an open top that is closed off in use by the pump 3. The cylindrical container 11 is provided with a waisted neck portion 12 which defines an undercut 20. The pump 3 is maintained in position on the cylindrical container 11 by means a ferrule 5 which is crimped against the undercut 20.

The pump 3 comprises a pump body that contains the working components of the pump 3. A valve stem 18 of the pump 3 extends from one end of the pump 3 as shown in Figure 1 and comprises a stepped cylindrical form having a first portion 15 of larger diameter and a second portion 16 of smaller diameter separated by a step. The second portion 16 defines a distal end 17 of the valve stem 18. The pump 3 and fluid reservoir 2 are conventional in design and will not be described further in detail. As typical for such pumps the valve stem 18 is reciprocally movable through a stroke of approximately 6 to 8 mm in order to actuate the pump 3 so as to discharge a metered dose of fluid out of the valve stem 18.

The actuator 4 comprises an actuator body 25 that is generally cup-shaped and defines a top wall 26 and a side wall 24 that extends therefrom. The side wall 24 extends into a side wall skirt 27 that has an enlarged diameter relative to the side wall 24 proximate the top wall 26. The actuator body 25 defines a delivery duct 28 that extends from a delivery duct socket 29 located on a central axis of the actuator 4 to a spray block socket 32 located in the side wall 24. The delivery duct 28 is thus L-shaped. As shown in Figure 2, a spray block 30 is locatable in the spray block socket 32 and defines an outlet orifice 31 for fluid discharge. The side wall skirt 27 is provided with a plurality of guidance ribs 33 on its inner surface.

As shown in Figures 1 to 3, the fluid delivery device 1 further comprises an auditory indicator for signalling when the valve stem 18 has been moved with respect to the fluid reservoir 2 through a sufficient stroke length to pump a required quantity of fluid from the fluid reservoir 2 into the delivery duct 28. The auditory indicator comprises a mechanical clicker 6 that is activated once the valve stem 18 has moved through a sufficient stroke length.

The mechanical clicker 6 comprises two components -a first component in the form of a clicker part 41 and a second component in the form of a mounting part 40.

The mounting part 40 comprises a disc 45 that is generally planar and is provided with a rim 46 at its outer edge. A cylindrical extension 47 is centrally provided which defines a bore 48 that passes through the disc 45.

The clicker part 41 comprises an integrally-formed framework comprising an inner annular ring 50 and an outer annular ring 51 which are joined together by three legs 52 equi-spaced 120° apart around the circumference of the annular rings. As most clearly shown in Figure 3, the plane of the inner annular ring 50, in the starting configuration, is positioned off-set axially from the plane of the outer annular ring 51. In other words, the legs 52 extend both radially and axially relative to the inner annular ring 50 and the outer annular ring 51. The clicker part 41 may be formed as a one-piece molding.

The inner annular ring 50 is provided with two downstands 53 in the form of protuberances which extend axially out of the plane of the inner annular ring 50. The two downstands 53 are arranged asymmetrically on the inner annular ring 50. In the illustrated example, both downstands 53 are located in one half of the inner annular ring 50, approximately 110 to 150° apart.

The outer annular ring 51 is provided with a flexible arm 54 which extends in a cantilevered fashion inwardly towards a centre of the clicker part 41. As shown in Figure 4, the flexible arm 54 extends to a radial point which is proximate, preferably substantially equal to, the outer radial extent of the inner annular ring 50. However, as can be seen in Figure 5a, the flexible arm 54 in the starting configuration lies in the plane of the outer annular ring 51 so that there exists an axial gap 59 between the flexible arm 54 and the inner annular ring 50.

The outer annular ring 51 is further provided with a skirt 55 at its outer edge which, on coupling of the mounting part 40 with the clicker part 41, receives the rim 46 of the disc 45. The skirt 55 may be provided with a snap bead to allow a snap-fit fixation of the clicker part 41 to the mounting part 40. Alternatively, the rim 46 may be bonded or adhered to the skirt 55.

The components of the actuator 4 and mechanical clicker 6 may be made of suitable engineering plastics materials. For example, thermoplastics such as polypropylene may be used. In one example the mechanical clicker 6 may be formed of acetal.

To assemble the fluid delivery device 1, the actuator 4 and mechanical clicker 6 can first be assembled into a sub-assembly as shown in Figure 5a by inserting the cylindrical extension 47 of the mechanical clicker 6 into the delivery duct socket 29 of the actuator body 25. The two components may be bonded together or a simple interference fit, preferably a tight fit, may be used.

-10 -The sub-assembly can then be mounted to the fluid reservoir 2 and pump 3 as shown in Figure 2 wherein the second portion 16 of the valve stem 18 of the pump 3 is matingly received in the bore 48 of the mounting part 40 of the mechanical clicker 6.

Figure 6a shows the assembled components in the starting configuration -in which the components have been fully assembled but are at rest. It will be noted that the side wall skirt 27 of the actuator 4 extends down into the region of the ferrule 5 with a lower portion of the guidance ribs 33 contacting a side wall of the ferrule 5. Further, it will be noted that the inner diameter of the inner annular ring 50 is larger than the outer diameter of the first portion 15 of the valve stem 18 about which it is arranged such that there is an annular gap 56 therebetween. It will also be seen that the downstands 53 lie a distance above the level of a leading face 21 of the ferrule 5. This leading face 21 forms a static surface as it will be appreciated that this surface does not move in operation of the pump 3 relative to the cylindrical container 11 or static internal components of the pump 3.

The fluid delivery device 1 is actuated by manually pressing down on the top wall 26 of the actuator 4 that thus performs the function of an actuator button. Figure 6b shows an intermediate configuration at the point where the downstands 53 first contact the leading face 21 of the ferrule 5. In moving into the intermediate configuration the guidance ribs 33 slide over the side wall of the ferrule 5 ensuring that the actuator 4 maintains its alignment relative to the longitudinal axis of the pump 3 and cylindrical container 11.

Continued depression of the actuator 4 causes the mechanical clicker 6 to move into the configuration shown in Figures 6c and 5b -the actuated configuration -in which the inner annular ring 50 has been moved relative to the outer annular ring 51 in order to compress the mechanical clicker 6. This compression causes the flexible arm 54 to be brought into contact with and clash with the inner annular ring 50. The degree of clashing of the two parts can be controlled by the number and location of the downstands 53 and the relative positions of the legs 52 and flexible arm 54. This is because in practice the compression of the mechanical clicker 6 does not cause the inner annular ring 50 to remain strictly parallel to the outer annular ring 51 and/or concentric to the outer annular ring 51 as it moves towards the outer annular ring 51. Rather, the presence of the downstands 53 causes the inner annular ring 50 to be offset from a concentric location and/or tilted with respect to the outer annular ring 51 during actuation. Since the downstands 53 are arranged asymmetrically, they will impart a tilting motion to the inner annular ring 50 when the downstands 53 are pushed against the leading face 21. Thus the half of the inner annular ring 50 where the downstands 53 are located with be tilted up and the other half tilted down. The tilting will also cause a marginal overlap between the inner annular ring 50 and the flexible arm 54 as they are brought into contact by closing the axial gap 59. Consequently the flexible arm 54 will clash with the inner annular ring 50. The actuation force on the actuator 4 is, however, sufficient to force the flexible arm 54 and/or the inner annular ring 50 to shift and/or deform elastically so that the flexible arm 54 can ride over the inner annular ring 50 into the position shown in Figure 5b wherein a side face of the flexible arm 54 is in face to face contact at point 60 with a side face of the inner annular ring 50. The required deformation is accompanied by an audible clicking sound that forms the auditory signal of the mechanical clicker 6.

Advantageously, the surrounding side wall 24 and side wall skirt 27 of the actuator 4 and the disc 45 of the mounting part 40 may act as an echo chamber to enhance the audibility of the clicking noise.

The degree of clashing of the flexible arm 54 with the inner annular ring 50 can be fine-tuned by shifting the location and/or spacing and/or number of the downstands 53. Advantageously, the use of the downstands 53 to offset and/or tilt the inner annular ring 20 facilitates forming the clicker part 41 more easily as a one-piece molding since the flexible arm 54 and inner annular ring 50 need have no radial 'overlap' in the resting configuration as molded.

The axial inter-spacing of the disc 45 and the flexible arm 54 may be small or zero. In this case, once the mechanical clicker 6 has clicked the inner annular ring 50 will have been brought into contact with the disc 45 thereby stopping further compression of the mechanical clicker 6 and also stopping the movement of the actuator 4 relative to the ferrule 5 and pump 3. Thus, in this manner, the mechanical clicker 6 can also act as an end stop limiting the stroke length of the pump 3. Alternatively, there may be provided a sufficient axial inter-spacing between the disc 45 and the flexible arm 54 that the inner annular ring 50 can move axially further beyond the point shown in Figure 5b to allow further stroking of the valve stem 18 after the click has sounded.

The mounting part 40, preferably the disc 45, may also be used to ensure that the flexible arm 54 is not pushed axially upwards either at all or by too large a distance when contacted by the inner annular ring 50. This may be achieved since the flexible arm 54 may be brought into contact with the disc 45 halting further upward movement.

Thus the mechanical clicker 6 helps to signal to a user when the valve stem 18 has been moved through at least a sufficient stroke length to dispense the fluid from the pump 3.

The pumped fluid is delivered out of the valve stem 18, into and through bore 48 and into and through the delivery duct 28. On reaching the spray block 30 the fluid may be -12 -atomised into a spray by known means such as a whirl chamber and discharged out of the outlet orifice 31.

On release of the actuator 4 after delivery, the valve stem 18 moves back into the starting configuration under the internal spring bias of the pump 3. The mechanical clicker 6 is thereby moved out of contact with the leading face 21 allowing the inner annular ring 50 to return to its staring position due to the elastic nature of its material. In particular, the resilient nature of the three legs 52 act as their own spring means which resets the mechanical clicker 6 without requiring any motive force from the internal spring of the pump 3.

In the present description the mechanical clicker 6 has been described in association with one example of pump 3. However, it will be appreciated that the mechanical clicker 6 may be utilised with other types of pump 3 and other configurations of fluid delivery device 1 where it is critical to achieve a minimum stroke length of an actuating member. For example, the fluid delivery device 1 may be provided with a dose counter that counts the number of dose dispensed from, or remaining in the fluid reservoir 2.

The fluid delivery device 1 has been illustrated with an actuator 4 and outlet orifice 31 adapted for oral delivery. However, the fluid delivery device 1 -and in particular the actuator 4 -may be altered to configure the device for other delivery pathways, for example nasal and sub-lingual.

The embodiment has been described to use a leading face 21 of the ferrule 5 as a static surface. Other static surfaces of the fluid delivery device 1 may be used and brought into contact with the mechanical clicker 6 during actuation.

In the illustrated and described embodiment the mechanical clicker 6 has been described as being mounted to the actuator 4 such that on actuation a portion of the mechanical clicker 6 is brought into contact with a static surface of the fluid delivery device 1, in particular the ferrule 5. In an alternative arrangement still forming part of the present disclosure the relative positions may be reversed such that the mechanical clicker 6 is mounted to a static surface of the fluid delivery device 1, for example the ferrule 5, and the actuator 4 is moved to bring it into contact with the inner annular ring 50 of the mechanical clicker 6.

Claims

-13 -CLAIMS: 1. A fluid dispensing device comprising a fluid reservoir, a pump and an actuator; the pump being mounted on the fluid reservoir and comprising a valve stem through which a fluid from the fluid reservoir is discharged on operation of the pump; the actuator being mounted on the valve stem of the pump and comprising a delivery duct, for receiving the fluid discharged from the valve stem of the pump, and an outlet orifice, for discharging said fluid; the actuator and valve stem being reciprocally movable with respect to the fluid reservoir so as to actuate the pump; wherein the fluid dispensing device is provided with an auditory indicator for signalling when the valve stem has been moved with respect to the fluid reservoir through a sufficient stroke length to pump a required quantity of fluid from the fluid reservoir into the delivery duct; wherein the auditory indicator comprises a mechanical clicker that is activated once the valve stem has moved through the sufficient stroke length.
2. A fluid dispensing device as claimed in claim 1, wherein the mechanical clicker is mounted to the valve stem, with no part of the mechanical clicker being mounted to the fluid reservoir or other part of the pump.
3. A fluid dispensing device as claimed in claim 1 or claim 2, wherein the mechanical clicker moves up and down with the valve stem during actuation of the pump.
4. A fluid dispensing device as claimed in any preceding claim, wherein after activation of the mechanical clicker, the mechanical clicker restricts the stroke length of the valve stem.
5. A fluid dispensing device as claimed in any preceding claim, wherein the mechanical clicker comprises a first part that is engagable against a static surface of the fluid dispensing device during stroking of the valve stem and a second part that can be engaged by the first part to produce an auditory clicking sound.
6. A fluid dispensing device as claimed in claim 5, wherein the first part and second part are compressed against one another to produce the auditory clicking sound.

-14 -
7. A fluid dispensing device as claimed in claim 5 or claim 6, wherein the first part comprises an annular ring that is disposed about the valve stem and/or pump and is contactable against the static surface.
8. A fluid dispensing device as claimed in claim 7, wherein the annular ring comprises one or more downstands that are contactable against the static surface.
9. A fluid dispensing device as claimed in claim 8, wherein the one or more downstands are arranged asymmetrically around the annular ring.
10. A fluid dispensing device as claimed in any of claims 5 to 9, wherein the second part comprises a flexible arm.
11. A fluid dispensing device as claimed in any of claims 5 to 10, wherein the first part and the second part are formed integrally, preferably as a single molding.
12. A fluid dispensing device as claimed in any of claims 5 to 11, wherein the first part comprises an inner annular ring that is disposed about the valve stem and is contactable against the static surface and the second part comprises an outer annular ring from which a flexible arm extends, wherein the inner annular ring is joined to the outer annular ring by a plurality of legs, and preferably the plurality of legs are configured to reset the first part relative to the second part after each actuation of the fluid dispensing device.
13. A fluid dispensing device as claimed in claim 12, wherein the plurality of legs comprises an odd number of legs, preferably three legs.
14. A fluid dispensing device as claimed in claim 12 or claim 13, wherein the flexible arm is located diametrically opposite one of the plurality of legs.
15. A fluid dispensing device as claimed in any of claims 12 to 14, wherein the inner annular ring comprises one or more downstands that are contactable against the static surface, wherein the one or more downstands are located only on one half of the inner annular ring, preferably that half nearest the flexible arm.

-15 -
16. A fluid dispensing device as claimed in any of claims 5 to 15, wherein the mechanical clicker further comprises a mounting part for mounting the first part and the second part to the actuator.
17. A fluid dispensing device as claimed in claim 16, wherein the mounting part comprises a socket for receiving a distal end of the valve stem.
18. A fluid dispensing device as claimed in any preceding claim, wherein the actuator comprises a cup-shaped actuator body having a top wall and a dependent side wall skirt; wherein the dependent side wall skirt is provided with a plurality of guiding ribs which can slidingly engage a surface of the pump or fluid reservoir to maintain axial alignment of the actuator relative to the valve stem.
19. A fluid dispensing device as claimed in any preceding claim, wherein the auditory indicator is coupled to the actuator such that in the case of removal of the actuator from the pump and fluid reservoir the actuator and auditory indicator remain coupled together.
20. A fluid dispensing device as claimed in any preceding claim, wherein the pump is a compression pump and the sufficient stroke length to pump a required quantity of fluid from the fluid reservoir into the delivery duct is greater than 6 mm.
21. An actuator for a fluid dispensing device, the actuator comprising: a delivery duct, for receiving, in use, a fluid discharged from a valve stem of a pump; an outlet orifice, for discharging said fluid; and an auditory indicator for signalling when a valve stem coupled to the actuator has been moved through a sufficient stroke length; wherein the auditory indicator comprises a mechanical clicker that is activated once the valve stem has moved through the sufficient stroke length.
22. A fluid dispensing device substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.