LIQUID DISPENSERS FOR NASA APPLICATIONS

Description

SCOPE OF APPLICATION AND STATE OF THE ART

[0001] The invention relates to a liquid dispenser for nasal applications. Such a dispenser serves the purpose of introducing pharmaceutical liquids into the nose and airways of a patient.

[0002] A generic liquid dispenser has a liquid reservoir in which the pharmaceutical liquid is stored before dispensing, and an elongated nasal applicator with at least one dispensing opening at its distal end through which the liquid is dispensed.

[0003] To dispense liquid, liquid dispensers of this type are provided with an actuation mechanism, which is achieved, in particular when dispensing the liquid in droplet form, by compressing the liquid reservoir, and, in particular when dispensing the liquid in atomized form, by an actuation handle that indirectly causes the liquid to be pressurized.

[0004] The present invention relates to liquid dispensers in which the liquid is atomized during dispensing, i.e., transformed into a mist of very small liquid droplets. In most dispensers of this type, this is achieved via a vortex chamber located upstream of the dispensing opening, into which the liquid is introduced tangentially. The resulting rapid rotating motion breaks the liquid into fine droplets upon exiting the dispenser. Document US 2008 / 081079 A1 represents relevant prior art. TASK AND SOLUTION

[0005] The object of the invention is to provide a liquid dispenser for nasal applications that does not require a vortex chamber and allows for particularly fine atomization of the liquid.

[0006] A liquid dispenser according to the invention has a nozzle plate with a plurality of nozzle openings at a distal end of the nasal applicator. The nozzle plate has at least 25 nozzle openings, the mean clear cross-sectional area of ​​which at the narrowest point is a maximum of 500 µm². However, designs with considerably more nozzle openings, which are preferably considerably smaller, are particularly preferred, as will be described below.

[0007] The liquid is released through the nozzle openings in the form of a multitude of fine jets, which break up beyond the nozzle openings ("Rayleigh breakup").

[0008] Due to the small nozzle openings required to break the stream into individual droplets, dispensing a sufficient quantity of liquid presents a challenge. The typical dispensing volume is usually between 50 µl and 150 µl. Nozzle plates from other dispensers typically only allow a flow rate of less than 50 µl / second, meaning that dispensing the aforementioned volume can take three seconds or more. In practice, however, experience has shown that such a lengthy dispensing process is unfamiliar to the user and can lead to premature termination of the dispensing action.

[0009] In order to ensure the reliable dispensing of such a quantity of liquid, it is proposed that the liquid dispenser have a conveying device for conveying the liquid from the liquid reservoir to the nozzle openings, which has a movable pressure element that, in the form of a piston or other movable wall, serves to pressurize the liquid.

[0010] To reposition this pressure element, the conveyor device has an actuating handle for manual repositioning, which is moved from a starting position to an actuated end position during actuation. It is designed so that the repositioning of the actuating handle is not directly transmitted to the pressure element. Instead, the actuating handle and the pressure element are connected via a spring accumulator, which is charged by moving the actuating handle to its end position and then moves the pressure element after the actuating handle has already reached its end position.

[0011] The movement of the actuating element therefore does not result in any or only a minimal simultaneous movement of the pressure element, as intended. Instead, the spring element, which can be designed, for example, as a helical spring or torsion spring (especially a metallic one), is tensioned. The movement of the pressure element is primarily driven by this spring element, which relaxes again after tensioning, once the actuating handle has already reached its end position.

[0012] The liquid dispenser is preferably designed such that, in the event of a sudden movement of the operating handle into its end position and thus a sudden tensioning of the spring accumulator, the subsequent dispensing of liquid by the spring accumulator takes at least 0.3 seconds, preferably at least 0.5 seconds, and particularly preferably at least 1 second. However, significantly longer periods are also possible, for example at least two seconds or even at least three seconds.

[0013] The discharge period is primarily determined by the flow resistance generated by the nozzle openings and the fluid pressure caused by the spring accumulator.

[0014] The aforementioned time periods, for example three seconds, are too long in practice to expect the patient to continuously apply force to the operating handle for such a duration. The spring accumulator provided according to the invention relieves the patient of this burden, as they can directly press the operating handle to its end position, thereby introducing the energy into the system that subsequently maintains the pressure on the fluid. If the spring element were not present and the operating handle were directly connected to the pressure element, immediate and rapid movement of the operating handle to its end position would not be possible, since the fluid discharge through the nozzle openings would not be sufficiently rapid, even at significantly increased pressure.

[0015] A liquid dispenser of the type described can be designed in two different ways.

[0016] In a first variant, the pressure element directly delimits the fluid reservoir. The pressure generated by the pressure element thus pressurizes the entire fluid. In particular, such a variant can be designed so that the fluid in the reservoir is dispensed in a single actuation or in two actuations. Such dispensers are also referred to as unit-dose dispensers or bi-dose dispensers. In this design, the pressure element is preferably part of a component shaped like a cylinder closed at one end, which is displaced as a whole relative to a piston that is stationary in relation to the nasal applicator.

[0017] In a second variant, the pressure element defines a pump chamber, specifically in the form of a piston that can be moved within the pump chamber. This pump chamber is part of a pumping device. It is connected to the fluid reservoir via an inlet channel with an inlet valve and to the nozzle openings via an outlet channel with an outlet valve. Accordingly, in this variant, the movement of the pressure element, driven indirectly via the operating handle and directly via the spring accumulator, does not pressurize the fluid in the fluid reservoir, but only the fluid in the pump chamber and downstream of it.

[0018] In the simplest case, with a liquid dispenser of the type described, it may be provided that the patient presses the actuating lever into the end position and holds it down until the spring mechanism has relaxed and the dispensing ends.

[0019] However, since this poses a risk of operator error due to premature termination of the force application, it is considered preferable to provide a self-engaging locking device on a housing section fixed to the nasal applicator, by means of which the actuating handle is secured in its end position. Such a locking device preferably comprises an elastically deflectable locking element with a chamfer, which is deflected by the actuating handle or a sub-element moving together with the actuating handle during actuation and, upon reaching the end position, engages with the actuating handle or the aforementioned sub-element under the pressure of the elastic deflection. Instead of being located on a housing section, the deflectable locking device can also be provided on the actuating handle or another sub-element moving with it.

[0020] The locking mechanism allows the patient to immediately cease applying force after activating the operating handle, as the end position is now held by the locking mechanism. Furthermore, the locking mechanism is advantageous because it provides the patient with an audible or tactile click indicating that the end position has been reached.

[0021] Particularly in the case of a dispenser intended for single use, this locking mechanism is preferably designed as a non-releasable locking mechanism. This means that the patient has no intended means of releasing the locking mechanism. In particular, the locking mechanism can be located in a place on the dispenser that is inaccessible to the patient, especially protected by the surrounding walls of the dispenser.

[0022] Alternatively, the locking mechanism can be designed as a detachable locking mechanism. This is particularly advantageous in the above-described design of the liquid dispenser with a pump mechanism, since the operating handle must be able to return to its initial position for further operation.

[0023] In a releasable locking device, a separate release button is preferably provided, which releases the locking mechanism. In particular, the elastically deflectable locking element described above can be displaced by this release button, thus releasing the operating handle. Under the pressure of the spring accumulator and / or a separate piston spring of the pump, the operating handle is then pressed back into its initial position.

[0024] Two designs of a dispenser according to the invention are preferred. In the first of these designs, the actuating handle is transversely displaceable in the direction of a principal extension direction of the nasal applicator and / or a principal dispensing direction, wherein the principal extension direction and the principal dispensing direction are preferably identical. It is particularly advantageous if the actuating handle is provided on the dispenser opposite the nasal applicator and is pressed upwards in the direction of the nasal applicator.

[0025] Preferably, for ease of use, at least one counter-force surface is provided for manual support, fixed to the nasal applicator. In particular, there may be two counter-force surfaces located on either side of the nasal applicator. The index and middle fingers are placed on these two counter-force surfaces, while the thumb rests on the operating handle, which is then pressed towards the counter-force surfaces during operation.

[0026] The second particularly preferred design provides that the liquid dispenser has an elongated housing oriented in a main direction of extension, with the nozzle openings located at its distal end and the liquid reservoir preferably located at its opposite end. In this design, the actuating handle is arranged laterally on the housing and thus eccentrically to a central axis. The actuating handle is actuated in the direction of the central axis, and either a pivoting or a translational actuating mechanism may be provided. Such a dispenser with a laterally mounted actuating handle is also referred to as a side-actuation dispenser.

[0027] The second design mentioned is particularly advantageous for dispensers with a pump unit. It is especially preferred that the pressure element can be displaced orthogonally to the dispenser's main axis of extension, meaning the pump unit is installed transversely within the housing. However, designs are also conceivable in which additional gear elements are provided between the operating handle and the pressure element to convert the force or its direction, thus allowing for a pump unit aligned with the main axis of extension.

[0028] The problem described at the beginning, namely that the fine nozzle openings require a long delivery time, can also be addressed by a liquid dispenser that is designed as a liquid dispenser for nasal applications in the manner described above and has a liquid reservoir as well as a nasal applicator with a nozzle plate, but with the additional special feature that the nozzle plate is designed for a comparatively large liquid flow.

[0029] According to the invention, the entirety of the nozzle openings is designed in such a way that a total liquid flow of at least 100 µl / second is achieved through the nozzle openings when liquid with the properties of water is present in a pre-chamber upstream of the nozzle plate under a pressure of 5 bar at the nozzle plate.

[0030] When using such a nozzle plate, the discharge volume of 50 µl to 150 µl, which is usually intended for the discharge of pharmaceutical liquids via nasal applicators per discharge process, can be discharged in 1.5 seconds or less.

[0031] Although a liquid dispenser with a spring-loaded accumulator and, in particular, a locking mechanism of the type described above is advantageous, when using a nozzle plate designed for a high liquid flow rate, and thus with a dispensing time of preferably 1.5 seconds or less, the spring element and the locking mechanism can be omitted. Instead, the patient can directly move the pressure element via the operating handle, thereby pressurizing the liquid. However, the use of a dispenser of the type described above with a spring-loaded accumulator is preferred.

[0032] Particularly preferred are designs of the nozzle plate that are designed for a total liquid flow rate between 100 µl / second and 750 µl / second at 5 bar liquid pressure, and especially preferably for a total liquid flow rate between 200 µl / second and 500 µl / second.

[0033] Several methods exist for achieving such large fluid flows. A design with between 400 and 2000 nozzle openings has proven particularly advantageous. Each nozzle opening has a minimum clear cross-sectional area between 10 µm² and 20 µm², preferably between 10 µm² and 15 µm². Preferably, the nozzle openings are round and have a corresponding minimum diameter, particularly between 1.5 µm and 3 µm.

[0034] Manufacturing such small nozzle openings is technically complex, which also increases the price of the liquid dispenser.

[0035] However, it has been shown that good results can also be achieved with a nozzle plate containing 200 to 1000 nozzle openings. In this case, the nozzle openings are somewhat larger and have a minimum clear cross-sectional area between 20 µm² and 50 µm², preferably between 25 µm² and 35 µm². For round nozzle openings, their diameter is in the range of 2.5 µm to 4 µm.

[0036] The manufacturing process can be further simplified by providing an even smaller number of nozzle openings, namely between 50 and 250 nozzle openings, each having a minimum clear cross-sectional area between 50 µm² and 100 µm², preferably between 70 µm² and 85 µm². In the case of round nozzle openings, their diameter is in the range between 4 µm and 6 µm.

[0037] These relatively large nozzle openings are not ideal in terms of atomization. However, they allow for achieving the aforementioned high total liquid flow rate of at least 100 µl / second at low manufacturing costs. This design can therefore be advantageous for inexpensive disposable dispensers.

[0038] Preferably, the aforementioned cross-sectional areas are the same for all nozzle openings. If the nozzle openings have different clear cross-sectional areas, it is considered preferred if at least 80% of the nozzle openings have the respective minimum cross-sectional areas mentioned.

[0039] The nozzle plate can be manufactured in various ways. One particularly preferred design involves using metallic nozzle plates manufactured by electroforming. In this process, metal, such as copper or nickel, is electrolytically deposited from an aqueous salt bath, thus creating the nozzle plate additively.

[0040] An alternative technique involves using a laser to create the nozzle openings in a blank. The blank nozzle plate can be made of thin metal, ceramic, glass, another mineral material, or plastic, into which the nozzle openings are then created using a laser beam, or preferably multiple laser beams.

[0041] A third option is to manufacture the nozzle plate from plastic, especially polypropylene, using injection molding, and thereby keeping the nozzle openings free of material by shaping the cavity used.

[0042] Due to the large number of nozzle openings, it is particularly important to prevent the exiting liquid jets from coming into contact with each other, as this would prevent fine atomization. The nozzle openings are therefore preferably arranged in a diverging orientation, with outer nozzle openings angled more sharply relative to the central discharge direction than inner nozzle openings. When manufacturing the nozzle openings by laser or electroforming, this can be achieved directly in the flat nozzle plate. However, it can also be achieved, in particular, by installing the nozzle plate in the liquid dispenser with a curved shape. Such a curvature can be enforced, for example, by an annular plastic carrier into which the nozzle plate is inserted. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Further advantages and aspects of the invention will become apparent from the claims and from the following description of preferred embodiments of the invention, which are explained below with reference to the figures. Fig. 1 shows a first embodiment of a dispenser according to the invention. Fig. 2 bis 4 show the nozzle unit of the dispenser Fig. 1 as well as its nozzle plate in a cutaway view and in a top view. Fig. 5A bis 5D show the process of activating the dispenser Fig. 1 . Fig. 6A bis 6D show a second embodiment of a dispenser according to the invention as well as the procedure for operating this dispenser. DETAILED DESCRIPTION OF THE EXECUTION EXAMPLES

[0044] Fig. 1 shows a liquid dispenser 10 according to the invention in a first embodiment.

[0045] The liquid dispenser 10 is designed for nasal applications and, for this purpose, has a nasal applicator 30 with an opening 31 at its distal end through which liquid can be dispensed. The nasal applicator 30 is formed externally by a housing component, which also includes further sub-components that are explained below.

[0046] For the purpose of fluid discharge, a conveying device 50 is provided, which has a sleeve-shaped actuating unit 53 inserted from below into a guide shaft 33 that is fixed to the nasal applicator. The underside of the actuating unit 53 is formed by an actuating handle 54. Counterforce surfaces 32 for this purpose are provided projecting from both sides of the nasal applicator 30.

[0047] A nozzle unit 40 is provided at the opening 31 at the distal end of the nasal applicator 30, which is located in Fig. 2 The nozzle unit 40 has a plastic sleeve 44 into which a nozzle plate 100 is inserted. Upstream of the nozzle plate 100, a pre-chamber 42 is provided in which pressurized liquid collects before being discharged through nozzle openings 102 of the nozzle plate 100.

[0048] Referring again to Fig. 1 Upstream of the nozzle unit 40, an internal component 80 is inserted into the nasal applicator 30, which is penetrated by a discharge channel 82. The opposite end of the internal component 80 is designed in the form of a piston 84, the outer surface of which slides and seals against the inner surface of a cylindrical fluid reservoir 20, the bottom of which is formed by a pressure element 52. The fluid reservoir 20 is axially displaceable relative to the internal component 80 and the nasal applicator, with the actuating unit 53 already described being provided for displacing the fluid reservoir 20 and the pressure element 52.

[0049] However, the actuating unit 53 on the one hand and the fluid reservoir 20 with pressure element 52 on the other hand are not directly connected to each other, but are instead coupled via a spring accumulator 60 in the form of a coil spring.

[0050] The Fig. 3 und 4 Figure 1 shows the nozzle plate 100 through which the liquid is discharged. The nozzle plate can be made of, for example, metal or ceramic. Approximately 1200 nozzle openings 102 are provided, penetrating the nozzle plate and each having a minimum clear cross-sectional area of ​​approximately 10 µm². Together, the nozzle openings allow a liquid flow rate of more than 100 µm / second at an upstream liquid pressure of 5 bar.

[0051] The nozzle openings 102 can be aligned parallel to each other. Preferably, however, the nozzle openings 102 are aligned diverging, with the outer nozzle openings 102 diverging more from the main direction of extension 2 than the inner nozzle openings 102. This ensures that the disintegration of the emerging liquid jets into individual droplets occurs as desired.

[0052] Based on the Fig. 5A bis 5D The handling of the liquid dispenser will be explained. Fig. 1 explained.

[0053] Fig. 5A shows an initial state of the liquid dispenser 10, which corresponds to the state of the Fig. 1 The liquid reservoir 20 is filled with a pharmaceutical liquid, which can reach the nozzle unit 40 via the discharge channel 82. However, in the initial state, the discharge channel 82 may be initially closed, for example by a membrane that can be destroyed under liquid pressure. Fig. 5A It is preferably provided, in a manner not shown in detail, that the actuating unit 53 and the lower end of the shaft 33 are interlocked or connected by thin plastic bridges, so that unintentional depressing of the actuating unit 53 is prevented and intentional depressing is accompanied by a perceptible pressure point.

[0054] Based on the state of the Fig. 5A The patient grasps the liquid dispenser 10 in such a way that his index and middle fingers are placed on the counterforce surfaces 32, while he places his thumb on the actuating handle 54 of the actuating unit 53. From this position, the actuating unit 53 is subjected to upward force by means of the thumb, thereby releasing the aforementioned locking mechanism or breaking the aforementioned plastic bridges.

[0055] The actuating force is also transmitted directly to the pressure element 52 and the fluid reservoir 20 via the spring accumulator 60. However, a large portion of the applied energy is initially absorbed by compression and thus tensioning of the spring accumulator 60. Immediate discharge of the fluid from the fluid reservoir 20 occurs only to a very limited extent, as the nozzle plate 100 permits only the aforementioned small fluid flow.

[0056] When the actuating unit 53 is fully depressed, it locks into place via locking elements 70, 72 against an inner surface of the shaft 33. This state is in Fig. 5B The actuating unit 53 remains in the depressed position due to the detent mechanism. The spring accumulator 60, under high tension, continues to press on the pressure element 52 and the fluid reservoir 20, thus reducing the volume of the fluid reservoir 20 and allowing fluid to be discharged over the next, for example, 1 to 2 seconds, as shown in Fig. 5C clarifies.

[0057] The liquid discharge only stops when the liquid reservoir 20 has been moved upwards far enough that the piston-like end 84 of the internal component 80 rests against the bottom of the liquid reservoir. This is in Fig. 5D clarifies.

[0058] The Fig. 6A bis 6D Figure 10 shows a second liquid dispenser 10 according to the invention, which is also designed as a liquid dispenser for the nasal application of pharmaceutical liquids. It therefore also has a nasal applicator 30, at the distal end of which a nozzle unit 40 is arranged according to the Fig. 2 bis 4 is planned.

[0059] Unlike the liquid dispenser of the Fig. 1 Is the liquid dispenser 10 of the Fig. 6A bis 6D However, it is designed as a pump dispenser. Its conveying device 50 therefore comprises a pump unit with a pump chamber 56, which is connected to the liquid reservoir 20 via an inlet channel and to the nozzle unit 40 via an outlet channel. The pump chamber 56 is delimited by a pressure element 52 in the form of a piston. A pressure-dependent opening and closing valve 58A, 58B is provided in both the inlet channel and the outlet channel, so that when the pump chamber enlarges by moving the pressure element 52 to the left, liquid is drawn from the liquid reservoir 20, and when the pressure element 52 is moved to the right, liquid is conveyed from the pump chamber 56 towards the nozzle unit 40.

[0060] To activate the liquid dispenser of the Fig. 6A bis 6D A pivotable operating handle 54 is provided on a side surface of the housing.

[0061] Again, it is provided that a spring accumulator 60 is located between the actuating handle 54 and the pressure element 52.

[0062] Starting from the initial state of the Fig. 6A When actuated, the actuating handle 54 is first pressed in, so that it enters the state of Fig. 6B It assumes this state. In this state, it is held by locking elements 70, 72, so that it does not initially return to the initial state of the Fig. 6A can return. Due to the movement of the actuating handle 54 into its end position, the spring accumulator 60 has been fully compressed, so that, starting from the state of Fig. 6B The piston-acting pressure element 52 is displaced towards the pump chamber 56, thereby reducing its volume. The liquid present in the pump chamber is conveyed through the discharge channel to the nozzle unit 40 and discharged through the nozzle openings 102, as shown in Fig. 6C shown

[0063] As soon as the discharge process ends, the patient presses the release button 74 as intended, thereby releasing the locking elements 70 and 72 from each other, which held the operating handle 54 in its end position. As in Fig. 6D As shown, the actuating handle 54 springs back to its initial position upon release, and a return spring 59 of the pumping device pushes the pressure element 52, which acts as a piston, to the left. The pump chamber 56 expands again, and fluid is drawn from the fluid reservoir 20.

[0064] This means the initial state of Fig. 6A restored and a renewed fluid discharge is feasible.

Claims

1. Liquid dispenser (10) for nasal applications, with the following features: a. the liquid dispenser (10) has a liquid reservoir (20) in which liquid is stored prior to discharge, and b. the liquid dispenser (10) has an elongated nasal applicator (30), and c. a nozzle plate (100) with a plurality of nozzle openings (102) is provided at a distal end of the nasal applicator (30), and d. all the nozzle openings (102) are designed in such a manner that a total liquid flow of at least 100 µl / second through the nozzle openings (102) is achieved if liquid with the properties of water in an antechamber (42) arranged upstream of the nozzle plate (100) under a pressure of 5 bar bears against the nozzle plate.

2. Liquid dispenser according to Claim 1, with the following further feature: a. the total liquid flow through the nozzle openings (102) is between 100 µl / second and 750 µl / second.

3. Liquid dispenser according to Claim 2, with the following further feature: a. the total liquid flow through the nozzle openings (102) is between 200 µl / second and 500 µl / second.

4. Liquid dispenser according to Claim 1, 2 or 3, with the following further feature: a. between 400 and 2000 nozzle openings (102) are provided, wherein the nozzle openings (102) have in each case a minimum clear cross-sectional surface area between 10 µm2 and 20 µm2.

5. Liquid dispenser according to Claim 4, with the following further feature: a. the nozzle openings (102) have in each case a minimum clear cross-sectional surface area between 10 µm2 and 15 µm2.

6. Liquid dispenser according to any one of the preceding claims, with the following further feature: a. between 200 and 1000 nozzle openings (102) are provided, wherein the nozzle openings (102) have in each case a minimum clear cross-sectional surface area between 20 µm2 and 50 µm2.

7. Liquid dispenser according to Claim 6, with the following further feature: a. the nozzle openings (102) have in each case a minimum clear cross-sectional surface area between 25 µm2 and 35 µm2.

8. Liquid dispenser according to any one of Claims 1 to 5, with the following further feature: a. between 50 and 250 nozzle openings (102) are provided, wherein the nozzle openings (102) have in each case a minimum clear cross-sectional surface area between 50 µm2 and 100 µm2.

9. Liquid dispenser according to Claim 8, with the following further feature: a. the nozzle openings (102) have in each case a minimum clear cross-sectional surface area between 70 µm2 and 85 µm2.

10. Liquid dispenser according to any one of the preceding claims, with the following further features: a. the nozzle plate (100) is formed as a metallic nozzle plate, which is produced by electroforming.

11. Liquid dispenser according to any one of Claims 1 to 9, with the following further feature: a. the nozzle plate (100) is produced as a metallic nozzle plate, as a ceramic nozzle plate, as a nozzle plate composed of glass or another mineral material or as a nozzle plate composed of plastic.

12. Liquid dispenser according to Claim 11, with the following further feature: a. the nozzle openings are incorporated by laser machining.

13. Liquid dispenser according to any one of Claims 1 to 9, with the following further feature: a. the nozzle plate (100) is manufactured from plastic, wherein the nozzle openings are incorporated in the course of injection moulding through the shaping of the cavity used in this case.

14. Liquid dispenser according to any one of the preceding claims, with the following further feature: a. the nozzle openings (102) have a diverging orientation, in particular with the additional feature: b. the nozzle plate is convexly arched.