Nozzle Arrangement

Abstract

In general terms the present invention proposes a nozzle arrangement 100 for delivering a liquid from a liquid delivery device. The nozzle arrangement 100 comprises a nozzle 102 having an inlet side 104 for receiving a liquid to be delivered and an outlet side 106 for delivering the liquid. The nozzle arrangement 100 also comprises a fixing device 120 for fixing the nozzle 102 in the delivery device and a recess 130 located at the outlet side 106 of the nozzle 102. The recess is 130 arranged to wick away liquid deposited on the nozzle 102 and/or fixing device 120.

Claims

1. A nozzle arrangement for delivering a liquid from a liquid delivery device, comprising: a nozzle having an inlet side for receiving a liquid to be delivered and an outlet side for delivering the liquid; a fixing device for fixing the nozzle in the delivery device; and a recess located at or near the outlet side of the nozzle, wherein the recess is arranged to wick away liquid deposited on the nozzle and/or fixing device.

2. The nozzle arrangement of claim 1, wherein the recess is located in the fixing device.

3. The nozzle arrangement of claim 1, wherein the recess is located between the fixing device and the nozzle.

4. The nozzle arrangement of claim 3, wherein the recess is defined by a chamfered or curved face of the fixing device.

5. The nozzle arrangement of claim 1, wherein the recess is square or rectangular in cross-section.

6. The nozzle arrangement of claim 1, wherein the recess is triangular or trapezoidal in cross-section.

7. The nozzle arrangement of claim 1, wherein the recess has an opening defined by a first width and a first length of the recess.

8. The nozzle arrangement of claim 7, wherein the first width and first length define a plane of the opening, and wherein the recess has depth orthogonal to the plane of the opening.

9. The nozzle arrangement of claim 7, wherein the first width of the recess is in a range of from 0.1 mm to 5 mm, optionally in a range of from 0.1 mm to 1 mm.

10. The nozzle arrangement of claim 7, wherein the first width narrows in the direction of the depth away from the opening.

11. The nozzle arrangement of claim 10, wherein the width narrows to zero in the direction of the depth away from the opening.

12. The nozzle arrangement of claim 7, wherein the depth of the recess is in a range of from 0.5 mm to 10 mm, optionally in a range of 0.5 mm to 5 mm.

13. The nozzle arrangement of claim 8, wherein the depth of the recess is parallel to the cylindrical axis of the nozzle.

14. The nozzle arrangement of claim 8, wherein the depth of the recess orthogonal to the cylindrical axis of the nozzle.

15. The nozzle arrangement of claim 1, wherein the recess has a length that extends at least partially along a circumference of the nozzle.

16. The nozzle arrangement of claim 1, wherein the recess has a length that defines a continuous loop extending a circumference of the nozzle.

17. The nozzle arrangement of claim 1, wherein the fixing device comprises a nut.

18. A liquid delivery device comprising a nozzle arrangement according to claim 1.

19. The liquid delivery device of claim 18, being an inhaler for nebulising pharmaceutical liquids.

20. The liquid delivery device of claim 18, being a soft mist inhaler (SMI).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0066] One or more embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: [0067] FIG. 1A is a cross-sectional view of a nozzle arrangement in accordance with a first embodiment of the invention; [0068] FIG. 1B is a cross-sectional view of the nozzle arrangement of FIG. 1A in which the recess is highlighted; [0069] FIG. 2 is a cross-sectional perspective view of the nozzle arrangement of FIG. 1A inside a liquid delivery device; [0070] FIG. 3 is a perspective view of the nozzle arrangement of FIG. 1A inside a liquid delivery device; [0071] FIG. 4 is a top view of the nozzle arrangement of FIG. 1A in which the recess is highlighted; [0072] FIG. 5 is a top view of a nozzle arrangement in accordance with a second embodiment of the invention in which the recess is highlighted; [0073] FIG. 6 is a cross-sectional view of a nozzle arrangement in accordance with a third embodiment of the invention; [0074] FIG. 7 is a cross-sectional view of a nozzle arrangement in accordance with a fourth embodiment of the invention; and [0075] FIG. 8 is a cross-sectional view of a nozzle arrangement in accordance with a fifth embodiment of the invention.

DETAILED DESCRIPTION

[0076] Referring to FIG. 1A, a nozzle arrangement 100 in accordance with a first embodiment of the invention comprises a nozzle 102 having an inlet side 104 for receiving a liquid to be delivered and an outlet side 106 for delivering the liquid. The nozzle 102 comprises a nozzle chip 107 and a generally conical shaped recess 108 in a nozzle holder 110. The nozzle chip 107 is surrounded by an annular elastomeric seal 111. The nozzle holder 110 has a central aperture 112 for allowing the flow of liquid to exit through the nozzle holder 110 from the nozzle chip 107.

[0077] The nozzle arrangement 100 also comprises a nut 120 for fixing the nozzle holder 110 in place in a delivery device (not shown). A recess 130 is arranged between the nozzle holder 110 and the nut 120, In this example, the recess 130 is rectangular in cross-section, and has a length that extends the whole way round the circumference of the nozzle 102 to form a continuous loop (i.e. ring). The recess 130 has a depth that extends generally parallel to the cylindrical axis of the nozzle 120, as shown in FIG. 1B, in which the recess 130 is highlighted as a shaded area.

[0078] In use, liquid is forced under pressure through the nozzle chip 107 and out through the aperture 112 of the nozzle holder 110 from the inlet side 104 to the outlet side 106. As the liquid exits the aperture 112 it is atomised to form an aerosol mist, which is directed away from the aperture 112 through the conical shaped recess 108. During atomisation, a small amount of the liquid may be deposited on the surfaces of the conical shaped recess 108, the nozzle holder 110 and/or the nut 120 on the outlet side 106, for example, as an accumulation of small droplets.

[0079] The deposited liquid is wicked away by the recess 130, for example, by capillary action. This reduces the amount of liquid deposited on the surfaces of the conical shaped recess 108, the nozzle holder 110 and/or nut 120 on the outlet side 106, thereby minimising or preventing disruption of the flow of further liquid exiting the nozzle chip 107 through the aperture 112.

[0080] FIG. 2 shows a cross-sectional perspective view of the nozzle arrangement 100. FIG. 3 shows a perspective view of the nozzle arrangement 100.

[0081] FIG. 4 shows a top view of the nozzle arrangement 100, in which the recess is highlighted as a shaded area. As can be seen from FIG. 4, the recess 130 has a length that extends the whole way round the circumference of the nozzle 102 to form a continuous loop (i.e. ring).

[0082] FIG. 5 shows a top view of a nozzle arrangement 200 in accordance with a second embodiment of the invention. The nozzle arrangement 200 is similar to the nozzle arrangement 100 in accordance with the first embodiment of the invention, comprising a nozzle 202 having an inlet side 204 (not visible in FIG. 5) for receiving a liquid to be delivered and an outlet side 206 for delivering the liquid. The nozzle 202 comprises nozzle chip 207 and a generally conical shaped recess 208 in a nozzle holder 210. The nozzle holder 210 has a central aperture 212 for allowing the flow of liquid to exit through the nozzle holder 210 from the nozzle chip 207.

[0083] The nozzle arrangement 200 also comprises a nut 220 for fixing the nozzle holder 210 in place in a delivery device (not shown). First and second recesses 230, 232 are arranged between the nozzle holder 210 and the nut 220. In this example, each of the recesses 230, 232 are rectangular in cross-section, and have a length that extends about 3/8 of the way round the circumference of the nozzle 202 to form two separate partial ring segments separated at each end by about 1/8 of the circumference of the nozzle 202. Each of the recesses 230, 232 has a depth that extends generally parallel to the cylindrical axis of the nozzle 220.

[0084] Referring to FIG. 6, a nozzle arrangement 300 in accordance with a third embodiment of the invention comprises a nozzle 302 having an inlet side 304 (not shown) for receiving a liquid to be delivered and an outlet side 306 for delivering the liquid. The nozzle 302 comprises a nozzle chip 307 and a generally conical shaped recess 308 in a nozzle holder 310. The nozzle holder 310 has a central aperture 312 for allowing the flow of liquid to exit through the nozzle holder 310 from the nozzle chip 307.

[0085] The nozzle arrangement 300 also comprises a nut 320 for fixing the nozzle holder 310 in place in a delivery device (not shown). A recess 330 is arranged between the nozzle holder 310 and the nut 320, In this example, the recess 330 is rectangular in cross-section, and has a length that extends the whole way round the circumference of the nozzle 302 to form a continuous loop (i.e. ring). The recess 330 has a depth that extends generally orthogonal to the cylindrical axis of the nozzle 302, as shown in FIG. 6, in which the recess 330 is highlighted as a shaded area.

[0086] Referring to FIG. 7, a nozzle arrangement 400 in accordance with a fourth embodiment of the invention comprises a nozzle 402 having an inlet side 404 (not shown) for receiving a liquid to be delivered and an outlet side 406 for delivering the liquid. The nozzle 402 comprises a nozzle chip 407 and a generally conical shaped recess 408 in a nozzle holder 410. The nozzle holder 410 has a central aperture 412 for allowing the flow of liquid to exit through the nozzle holder 410 from the nozzle chip 407.

[0087] The nozzle arrangement 400 also comprises a nut 420 for fixing the nozzle holder 410 in place in a delivery device (not shown). A recess 430 is arranged between the nozzle holder 410 and the nut 420. In this example, the recess 430 is triangular (i.e. wedge shaped) in cross-section, and has a length that extends the whole way round the circumference of the nozzle 402 to form a continuous loop (i.e. ring). The recess 430 has a depth that extends generally orthogonal to the cylindrical axis of the nozzle 402, as shown in FIG. 7, in which the recess 430 is highlighted as a shaded area.

[0088] Referring to FIG. 8, a nozzle arrangement 500 in accordance with a fifth embodiment of the invention comprises a nozzle 502 having an inlet side 504 (not shown) for receiving a liquid to be delivered and an outlet side 506 for delivering the liquid. The nozzle 502 comprises a nozzle chip 507 and a generally conical shaped recess 508 in a nozzle holder 510. The nozzle holder 510 has a central aperture 512 for allowing the flow of liquid to exit through the nozzle holder 510 from the nozzle chip 507.

[0089] The nozzle arrangement 500 also comprises a nut 520 for fixing the nozzle holder 510 in place in a delivery device (not shown). A recess 530 is arranged between the nozzle holder 510 and the nut 520. In this example, the recess 530 is curved in cross-section, and has a length that extends the whole way round the circumference of the nozzle 502 to form a continuous loop (i.e. ring). The recess 530 has a depth that extends away from the opening of the recess 520 in a direction generally parallel to the cylindrical axis of the nozzle 502 and gradually curves away such that the depth extends generally perpendicular to the cylindrical axis of the nozzle 502 at the lowermost end (i.e. the bottom) of the recess 530.

EXAMPLES

Comparative Example (Not in Accordance With the Invention)

[0090] A Malvern Panalytical® Spraytec™ laser diffraction system was used to observe the droplet diameters over a number of actuations (i.e. spay events) for a delivery device comprising a nozzle arrangement in accordance with the first embodiment of the invention, however, in which the recess was filled in (i.e. blocked). In this example, a high average Dv90 was observed, along with a high variability in the droplet size. The Dv90 value indicates that 90% of the spray volume is contained in droplets that are smaller than the Dv90 value, and 10% is contained in droplets that are larger than the Dv90 value. The high average Dv90 was attributed to droplets forming on the nozzle and running back into the path of the central aperture of the nozzle holder and disrupting the spray formed by the nozzle chip.

Example 1

[0091] A Malvern Panalytical® Spraytec™ laser diffraction system was used to observe the droplet diameters over a number of actuations (i.e. spay events) for a delivery device comprising the nozzle arrangement used in the comparative example above, however, in this example the wicking recess was not filled in (i.e. blocked). In this example, a lower average Dv90 was observed, with less variability in the size of droplets within an actuation and between actuations. The wicking recess was found to reduce the occurrence of droplets running back into the path of the central aperture of the nozzle holder and therefore reduce disruption to the spray formed by the nozzle chip. This resulted in less variability in the droplet sizes and a reduction in the average Dv90.