FLUID DELIVERY DEVICE, METHOD OF OPERATING THE FLUID DELIVERY DEVICE AND OSCILLATOR SYSTEM FOR THE FLUID DELIVERY DEVICE

Abstract

The invention relates to a fluid delivery device (2, 2) for delivering a fluid into a human or animal body. The fluid delivery device (2, 2) comprises a fluid chamber (4, 4) for receiving a fluid, an oscillator (6, 6) for imparting oscillations to at least a portion of the fluid and a control for controlling the oscillator (6, 6). The oscillator (6, 6) comprises a vibrator (8, 8) and a resonator (10, 10). The resonator (10, 10) has a main body (12, 12), defining an interior volume (14, 14), and a neck (16, 16). The neck (16, 16) is connected to the main body (12, 12) and in fluid communication with the interior volume (14, 14). The vibrator (8, 8) is configured to impart vibrations to the resonator (10, 10). The control is configured to control operation of the vibrator (8, 8) so as to impart vibrations to the resonator (10, 10) at a resonance frequency of the resonator (10, 10) or at a frequency which is within 20% of a resonance frequency of the resonator (10, 10). The invention further relates to a method of operating the fluid delivery device (2, 2).

Claims

1. A fluid delivery device for delivering a fluid into a human or animal body, wherein the fluid delivery device comprises: a fluid chamber for receiving a fluid; an oscillator for imparting oscillations to at least a portion of the fluid; and a control for controlling the oscillator; wherein the oscillator comprises a vibrator and a resonator, the resonator has a main body, defining an interior volume, and a neck, the neck is connected to the main body and in fluid communication with the interior volume, the vibrator is configured to impart vibrations to the resonator, and the control is configured to control operation of the vibrator so as to impart vibrations to the resonator at a resonance frequency of the resonator or at a frequency which is within 20% of a resonance frequency of the resonator.

2. A fluid delivery device for delivering a fluid into a human or animal body, wherein the fluid delivery device comprises a fluid chamber for receiving a fluid; an oscillator for imparting oscillations to at least a portion of the fluid; and a control for controlling the oscillator; wherein the oscillator comprises a vibrator and a resonator, the fluid chamber forms a main body of the resonator, defining an interior volume, the resonator has the main body and a neck, the neck is connected to the main body and in fluid communication with the interior volume, the vibrator is configured to impart vibrations to the resonator, and the control is configured to control operation of the vibrator so as to impart vibrations to the resonator at a resonance frequency of the resonator or at a frequency which is within 20% of a resonance frequency of the resonator.

3. The fluid delivery device according to claim 1, further comprising a fluid conveying element for inducing a fluid flow of at least a portion of the fluid received in the fluid chamber, wherein the oscillator is configured to impart oscillations to the fluid flow.

4. The fluid delivery device according to claim 1, wherein the fluid delivery device is an aerosol delivery device and the fluid is or contains an aerosol.

5. The fluid delivery device according to claim 4, further comprising an aerosol generator for generating an aerosol.

6. The fluid delivery device according to claim 1, wherein the vibrator comprises a vibratable membrane.

7. The fluid delivery device according to claim 1, wherein the main body of the resonator comprises a vibratable membrane.

8. The fluid delivery device according to claim 1, wherein the control is configured to control operation of the vibrator so as to impart vibrations to the resonator at a constant frequency, the constant frequency being a resonance frequency of the resonator or a frequency which is within +20% of a resonance frequency of the resonator.

9. The fluid delivery device according to claim 1, wherein the control is configured to control operation of the vibrator so as to impart vibrations to the resonator at a plurality of different frequencies, and at least one of the plurality of frequencies is a resonance frequency of the resonator or a frequency which is within 20% of a resonance frequency of the resonator.

10. The fluid delivery device according to claim 1, wherein the resonator has a single resonance frequency or a plurality of resonance frequencies.

11. The fluid delivery device according to claim 1, wherein an inner cross-section of the neck, perpendicular to a fluid path direction in the neck, is substantially constant along the fluid path direction in the neck.

12. The fluid delivery device according to claim 1, wherein the interior volume of the main body has a cylindrical shape or a spherical shape.

13. The fluid delivery device according to claim 1, wherein a length of the neck in a fluid path direction in the neck is in the range of 15 mm to 150 mm, preferably 25 mm to 75 mm.

14. The fluid delivery device according to claim 1, wherein an inner diameter of the neck, perpendicular to a fluid path direction in the neck, is in the range of 1.0 mm to 30.0 mm, preferably 5.0 mm to 20.0 mm.

15. The fluid delivery device according to claim 1, wherein the size of the interior volume of the main body is in the range of 10 ml to 800 ml, preferably 50 ml to 400 ml.

16. The fluid delivery device according to claim 1, wherein the resonator has at least one resonance frequency in the range of 10 Hz to 200 Hz, preferably in the range of 20 Hz to 100 Hz.

17. The fluid delivery device according to claim 1, further comprising an adaptation element for adaptation to the respiratory system of a human or animal body.

18. The fluid delivery device according to claim 1, wherein the oscillator is removably attached to a remainder of the fluid delivery device, or the oscillator is integrally formed with a remainder of the fluid delivery device.

19. The fluid delivery device according to claim 1, wherein the vibrator is removably attached to a remainder of the fluid delivery device, or the vibrator is integrally formed with a remainder of the fluid delivery device.

20. A method of operating the fluid delivery device according to claim 1, the method comprising: controlling operation of the vibrator so as to impart vibrations to the resonator at a resonance frequency of the resonator or at a frequency which is within 20% of a resonance frequency of the resonator.

21. An oscillator system for the fluid delivery device according to claim 1, wherein the oscillator system comprises: an oscillator for imparting oscillations to at least a portion of the fluid; and a control for controlling the oscillator; wherein the oscillator comprises a vibrator and a resonator, the resonator has a main body, defining an interior volume, and a neck, the neck is connected to the main body, and in fluid communication with the interior volume, the vibrator is configured to impart vibrations to the resonator, and the control is configured to control operation of the vibrator so as to impart vibrations to the resonator at a resonance frequency of the resonator or at a frequency which is within 20% of a resonance frequency of the resonator.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0160] Hereinafter, non-limiting examples of the present invention are explained with reference to the drawings, in which:

[0161] FIGS. 1A and 1B show a fluid delivery device according to a first embodiment of the present invention, wherein FIG. 1A is a front view of the fluid delivery device, and FIG. 1B is a partial cross-sectional view of the fluid delivery device taken along the line A-A in FIG. 1A;

[0162] FIGS. 2A and 2B show a fluid delivery device according to a second embodiment of the present invention, wherein FIG. 2A is a front view of the fluid delivery device, and FIG. 2B is a partial cross-sectional view of the fluid delivery device taken along the line A-A in FIG. 2A;

[0163] FIG. 3 is a diagram showing measurement results for the vibration pressure amplitude as a function of the vibration frequency for the fluid delivery device of the first embodiment;

[0164] FIG. 4 is a diagram showing measurement results for the vibration pressure amplitude as a function of the electric power applied to the vibrator for the fluid delivery device of the first embodiment; and

[0165] FIG. 5 is an exploded perspective view of a fluid delivery device according to a third embodiment of the present invention.

DETAILED DESCRIPTION OF CURRENTLY PREFERRED EMBODIMENTS

[0166] Currently preferred embodiments of the present invention will now be described with reference to the accompanying drawings. The preferred embodiments relate to fluid delivery devices and to methods of operating these devices.

[0167] In the following, a first embodiment of the fluid delivery device of the present invention and of the operating method of the present invention will be described with reference to FIGS. 1A and 1B.

[0168] FIGS. 1A and 1B show a fluid delivery device 2 for delivering a fluid into a human or animal body according to a first embodiment of the present invention.

[0169] The fluid delivery device 2 comprises a fluid chamber 4 for receiving a fluid, an oscillator 6 for imparting oscillations to at least a portion of the fluid, and a control (not shown) for controlling the oscillator 6. The control may be, for example, a computer, a processor, such as a microprocessor, a circuit or the like.

[0170] The oscillator 6 comprises a vibrator 8 and a resonator 10. The resonator 10 has a main body 12, defining an interior volume 14, and a neck 16, as is shown in FIGS. 1A and 1B. The neck 16 is connected to the main body 12 and in fluid communication with the interior volume 14 (see FIG. 1B). The neck 16 defines an inner space 18 which, at one end thereof, is open to the interior volume 14 and, at the other end thereof, is open to the outside of the resonator 10. The interior volume 14 of the main body 12 and the inner space 18 of the neck 16 each have a cylindrical shape.

[0171] The interior volume 14 is in fluid communication with the fluid chamber 4 through the inner space 18 of the neck 16.

[0172] The fluid delivery device 2 is an aerosol delivery device for delivering an aerosol as the fluid into a human or animal body. Specifically, the fluid delivery device 2 is a jet nebuliser or atomiser in which an aerosol is generated by causing a compressed gas, such as air or oxygen, to exert aerodynamic forces on a liquid drug or medicament to be aerosolised. The compressed gas may be provided by a compressor (not shown). The fluid delivery device 2 has a connection 20 through which the compressed gas is supplied.

[0173] The oscillator 6, comprising the vibrator 8 and the resonator 10, is removably or detachably attached to a remainder of the fluid delivery device 2. For example, the oscillator 6 may be removably or detachably attached to a PARI LC Sprint nebuliser.

[0174] The oscillator 6 and the control together form an embodiment of the oscillator system of the present invention.

[0175] An aerosol or fluid comprising the gas and the aerosolised drug or medicament is received in the fluid chamber 4. From the fluid chamber 4, the aerosol or fluid is transported outside the device 2 into a human or animal body through a mouthpiece or nosepiece 22. The mouthpiece or nosepiece 22 is configured for adaptation to the respiratory system of the human or animal body.

[0176] A fluid flow for transporting at least a portion of the fluid received in the fluid chamber 4 outside the device 2 is induced by the member or component providing the compressed gas for aerosol generation, such as a compressor. Hence, in the fluid delivery device 2 of the first embodiment, this member or component serves as a fluid conveying element. The oscillator 6 is configured to impart oscillations to the fluid flow.

[0177] In the interior volume 14 and the inner space 18, a fluid, e.g., a gas, such as air, is received. The fluid can pass through the inner space 18 in a fluid path direction F (see FIG. 1B) which is the direction from the one end of the inner space 18, which is open to the interior volume 14, to the other end of the inner space 18, which is open to the outside of the resonator 10. The fluid path direction F coincides with an arrangement direction along which the main body 12 and the neck 16 are arranged relative to each other.

[0178] An inner cross-section of the neck 16, i.e., a cross-section of the inner space 18, perpendicular to the fluid path direction F is significantly smaller than a cross-section of the interior volume 14 perpendicular to the fluid path direction F (see FIG. 1B).

[0179] The vibrator 8 is configured to impart vibrations to the resonator 10, in particular, the main body 12. The vibrator 8 comprises a vibratable membrane (not shown). The vibratable membrane is a continuous membrane, i.e., a membrane which does not have openings or holes that fully penetrate the membrane formed therein. The vibratable membrane is arranged so that it substantially lies in a plane which is perpendicular to the fluid path direction F. Thus, the direction along which the vibrations are imparted to the resonator 10 by the vibrator 8 is parallel to the fluid path direction F.

[0180] In other embodiments, the vibratable membrane may be arranged so that it substantially lies in a plane which is parallel to the fluid path direction F.

[0181] For example, the vibrator 8 may be substantially in the form of a loudspeaker.

[0182] The vibrator 8 imparts vibrations to the main body 12, thus vibrating the fluid, such as air, received in the interior volume 14. The resonator 10, having the main body 12 and the neck 16, is a Helmholtz resonator having a predetermined resonance frequency. The resonance frequency of the resonator 10 is approximately 45 Hz (see FIG. 3).

[0183] The control is configured to control operation of the vibrator 8 so as to impart vibrations to the Helmholtz resonator 10 at the resonance frequency thereof or at a frequency which is within 20% of the resonance frequency thereof. Thus, the vibrations imparted by the vibrator 8 are amplified by the resonator 10 through acoustic resonance. The amplified vibrations are used to oscillate the fluid flow, i.e., to impart oscillations to the fluid flow. The oscillations are imparted to the fluid flow through the end of the inner space 18 which is open to the outside of the resonator 10. This end of the inner space 18 is in fluid communication with the fluid chamber 4.

[0184] The control may be configured to control operation of the vibrator 8 so as to impart vibrations to the main body 12 at a constant frequency, namely the resonance frequency of the resonator 10 or a frequency which is within 20% of the resonance frequency of the resonator 10, or at a plurality of different frequencies, wherein at least one of the frequencies is the resonance frequency of the resonator 10 or a frequency which is within 20% of the resonance frequency of the resonator 10. In particular, the control may be configured to scan a frequency band comprising the resonance frequency of the resonator 10 or a frequency which is within 20% of the resonance frequency of the resonator 10.

[0185] The length of the neck 16 in the fluid path direction F is approximately 50 mm. The inner diameter of the neck 16, perpendicular to the fluid path direction F, is approximately 8 mm. The size of the interior volume 14 of the main body 12 is approximately 100 ml.

[0186] In operation of the fluid delivery device 2, the compressed gas is supplied to the device 2 through the connection 20 and produces droplets of a saline, liquid drug or medicament received in the device 2. The aerosol or fluid containing the gas and the droplets of saline, drug or medicament is received in the fluid chamber 4 and transported outside the device through the mouthpiece or nosepiece 22 by the fluid flow induced by the member or component providing the compressed gas, such as a compressor.

[0187] Operation of the vibrator 8 is controlled so as to impart vibrations to the main body 12 at the resonance frequency of the resonator 10 or at a frequency which is within 20% of the resonance frequency of the resonator 10. The vibrations imparted to the main body 12 are amplified by the resonator 10, so that oscillations with a significantly increased pressure amplitude are imparted to the flow of the fluid containing the aerosolised drug or medicament.

[0188] In this way, it can be ensured that the aerosolised drug or medicament is also supplied to regions of the human or animal body which otherwise are difficult to reach, such as the paranasal sinuses or some areas of the lungs.

[0189] In the following, a second embodiment of the fluid delivery device of the present invention and of the operating method of the present invention will be described with reference to FIGS. 2A and 2B.

[0190] The second embodiment of the invention substantially differs from the first embodiment of the invention in that the oscillator is integrally formed with a remainder of the fluid delivery device and the aerosol is generated in a different manner, as will be detailed below.

[0191] FIGS. 2A and 2B show a fluid delivery device 2 for delivering a fluid into a human or animal body according to the second embodiment of the present invention. The fluid delivery device 2 is an aerosol delivery device for delivering an aerosol as the fluid into the human or animal body. Specifically, the fluid delivery device 2 is a vibrating membrane aerosol delivery device comprising a vibrating membrane aerosol generator 24 for generating an aerosol (see FIG. 2B). The vibrating membrane aerosol generator 24 comprises a perforated vibratable membrane (not shown).

[0192] The fluid delivery device 2 comprises a liquid reservoir 26 for receiving a liquid drug or medicament. Further, the device 2 includes a cap 28, such as a screw cap, with which the liquid reservoir 26 can be closed after filling the liquid drug or medicament into the reservoir 26. The liquid drug or medicament filled into the liquid reservoir 26 comes into contact with the perforated vibratable membrane of the aerosol generator 24. The membrane is provided with a plurality of openings or holes with diameters in the micrometer range that fully penetrate the membrane. The perforated membrane can be vibrated or oscillated, for example, by means of a piezoelectric element (not shown), such that the direction of the vibrations is perpendicular to the plane of the membrane. The plane of the membrane is arranged horizontally in the arrangement shown in FIGS. 2A and 2B.

[0193] By inducing vibrations in the perforated membrane of the aerosol generator 24, the liquid drug or medicament contained in the liquid reservoir 26 is passed through the openings or holes of the membrane and aerosolised into a fluid chamber 4 of the fluid delivery device 2. The fluid chamber 4 is formed at the other side, opposite the liquid reservoir 26, of the perforated membrane. A detailed description of this concept is given, for example, in U.S. Pat. No. 5,518,179.

[0194] The fluid delivery device 2 comprises an oscillator 6 for imparting oscillations to at least a portion of the fluid received in the fluid chamber 4. The oscillator 6 comprises a vibrator 8 and a resonator 10 (see FIG. 2B).

[0195] As has been indicated above, in the fluid delivery device 2 of the second embodiment, the oscillator 6 is integrally formed with a remainder of the device 2. Specifically, as is shown in FIG. 2B, the fluid chamber 4 forms a main body 12 of the resonator 10, defining an interior volume 14. The resonator 10 has the main body 12, defining the interior volume 14, and a neck 16 which defines an inner space 18. The neck 16 is connected to the main body 12 and in fluid communication with the interior volume 14. As is schematically shown in FIG. 2B, both the interior volume 14 and the inner space 18 have an irregular shape.

[0196] The vibrator 8 is configured to impart vibrations to the main body 12 of the resonator 10. The vibrator 8 of the device 2 of the second embodiment has substantially the same configuration as the vibrator 8 of the device 2 of the first embodiment. Hence, a detailed description thereof has been omitted.

[0197] The fluid delivery device 2 further comprises a mouthpiece or nosepiece 22 for adaptation to the respiratory system of the human or animal body. The aerosol as the fluid received in the fluid chamber 4 is transported outside the device 2 through the mouthpiece or nosepiece 22.

[0198] A fluid flow of at least a portion of the fluid received in the fluid chamber 4 is induced by the respiration, i.e., the inhalation, of the patient or by one or more inlet valves (not shown) provided in the fluid delivery device 2. The one or more inlet valves are configured to exploit the oscillations of a fluid, e.g., a gas, such as air, received in the interior volume 14 so as to generate a fluid flow for transporting aerosol as the fluid outside the device 2. Alternatively, the fluid delivery device 2 may be provided with a different fluid conveying element, such as a pump or the like.

[0199] The oscillator 6 is configured to impart oscillations to the fluid flow.

[0200] Further, the fluid delivery device 2 comprises a control (not shown) for controlling the oscillator 6. The control is configured to control operation of the vibrator 8 so as to impart vibrations to the main body 12 of the resonator 10 at a resonance frequency of the resonator 10 or at a frequency which is within 20% of a resonance frequency of the resonator 10.

[0201] The oscillator 6 and the control together form an embodiment of the oscillator system of the present invention.

[0202] The configuration and the operation of the control of the device 2 of the second embodiment are substantially the same as the configuration and the operation, respectively, of the device 2 of the first embodiment. Hence, a detailed description thereof has been omitted.

[0203] The resonator 10, having the main body 12 and the neck 16, is a Helmholtz resonator. The resonator 10 may have a single resonance frequency or a plurality of resonance frequencies. The control may be configured to control operation of the vibrator 8 so as to impart vibrations to the main body 12 at one or more of the resonance frequencies of the resonator 10 or at one or more frequencies which are within 20% of a resonance frequency of the resonator 10 In particular, the control may be configured to scan a frequency band comprising one or more of these resonance frequencies or one or more frequencies which are within 20% of a resonance frequency of the resonator 10.

[0204] In operation of the fluid delivery device 2, a liquid drug or medicament is filled into the liquid reservoir 26 and the liquid reservoir 26 is closed with the cap 28. Subsequently, the aerosol generator 24 is actuated, i.e., the perforated vibrating membrane thereof is vibrated, so as to aerosolise the liquid drug or medicament received in the liquid reservoir 26 into the fluid chamber 4. A fluid flow is induced in at least a portion of the aerosol received in the fluid chamber 4, e.g., by the inhalation of the patient through the mouthpiece or nosepiece 22, by one or more inlet valves provided in the device 2 or by a different fluid conveying element, such as a pump or the like, and oscillations are imparted to the fluid flow by the oscillator 6. For imparting these oscillations, operation of the vibrator 8 is controlled by the control so as to vibrate the main body 12, i.e., a fluid received in the interior volume 14 thereof, at a resonance frequency of the resonator 10 or at a frequency which is within 20% of a resonance frequency of the resonator 10.

[0205] In this way, the aerosol can be efficiently delivered to regions of the human or animal body which otherwise are difficult to reach, in substantially the same manner as for the fluid delivery device 2 of the first embodiment.

[0206] The fluid delivery device 2 of the second embodiment is a hand-held and portable device enabling a particularly convenient and efficient aerosol delivery.

[0207] FIG. 3 is a diagram showing measurement results of the pressure amplitude of the vibrations amplified by the resonator 10 of the fluid delivery device 2 of the first embodiment as a function of the frequency of the vibrations imparted to the main body 12 by the vibrator 8. As is indicated in FIG. 3, the pressure amplitude is given in arbitrary units and the frequency is given in Hz.

[0208] The resonance frequency of the resonator 10, i.e., the frequency at which maximum amplification of the vibrations occurs, is approximately 45 Hz in this example (see FIG. 3). As is further evident from FIG. 3, the pressure amplitude can be significantly increased by suitably choosing the frequency of the vibrator 8.

[0209] FIG. 4 is a diagram showing measurement results for the pressure amplitude of the vibrations amplified by the resonator 10 of the fluid delivery device 2 of the first embodiment as a function of the electric power applied to the vibrator 8. The electric power is given in W. The pressure amplitude has been normalised by dividing the measured values by respective pressure amplitudes measured for a conventional pulsating aerosol nebuliser. The pressure amplitude is thus given in FIG. 4 in percent of the pressure amplitude of the conventional pulsating aerosol nebuliser. For the measurement shown in FIG. 4, the vibrator 8 was operated to impart vibrations to the main body 12 at a constant frequency of 50 Hz.

[0210] As is shown in FIG. 4, the pressure amplitude increases significantly with increasing electric power. Already at an electric power of approximately 1.5 W, pressure amplitudes of the order of those achievable with the conventional pulsating aerosol nebuliser are obtained (see the vertical dashed line in FIG. 4). If the electric power is further increased to approximately 4.5 W, about 150% of the pressure amplitude of the conventional pulsating aerosol nebuliser are achieved.

[0211] Due to the low power consumption of the fluid delivery device 2, the oscillator 6 can be continuously operated for approximately 2 to 3 hours at a pressure amplitude of about 100% of the pressure amplitude of the conventional pulsating aerosol nebuliser using a AA type battery as the power source.

[0212] The fluid delivery device of the present invention thus allows for a fluid to be delivered into a human or animal body in an efficient manner, while providing a compact device configuration, reduced power consumption, a decreased noise level and greater flexibility.

[0213] In the following, a third embodiment of the fluid delivery device of the present invention will be described with reference to FIG. 5.

[0214] The third embodiment of the invention substantially differs from the second embodiment of the invention in that the vibratable membrane of the vibrator is driven by a mechanical drive.

[0215] FIG. 5 shows an exploded perspective view of a fluid delivery device 102 for delivering a fluid into a human or animal body according to the third embodiment of the present invention.

[0216] The fluid delivery device 102 comprises a fluid chamber 104 for receiving a fluid and an oscillator 106 for imparting oscillations to at least a portion of the fluid. The oscillator 106 comprises a vibrator 108 and a resonator 110. The vibrator 108 comprises a vibratable membrane 109. The vibratable membrane 109 is a continuous membrane, i.e., a membrane which does not have openings or holes formed therein that fully penetrate the membrane. The fluid chamber 104 forms a main body 112 of the resonator 110.

[0217] The fluid delivery device 102 further comprises a liquid reservoir 126 for receiving a liquid drug or medicament. Moreover, the device 102 includes a cap 128, such as a screw cap, with which the liquid reservoir 126 can be closed after filling the liquid drug or medicament into the reservoir 126.

[0218] The fluid delivery device 102 is an aerosol delivery device for delivering an aerosol as the fluid into the human or animal body. Specifically, the fluid delivery device 102 is a vibrating membrane aerosol delivery device comprising a vibrating membrane aerosol generator 124 for generating an aerosol. The vibrating membrane aerosol generator 124 comprises a perforated vibratable membrane (not shown). The fluid delivery device 102 further comprises a control unit 130 for controlling operation of the aerosol generator 124.

[0219] The fluid delivery device 102 also comprises a nosepiece 122 for adaptation to the nose of a human or animal patient. The aerosol as the fluid received in the fluid chamber 104 is transported outside the device 102 and into the nose of the patient through the nosepiece 122.

[0220] The general configuration and operation of the components identified above are substantially the same as the general configuration and operation, respectively, of the corresponding components of the device 2 of the second embodiment. Hence, a repeated detailed description thereof has been omitted.

[0221] The fluid delivery device 102 according to the third embodiment substantially differs from the fluid delivery device 2 according to the second embodiment in that the vibratable membrane 109 of the vibrator 108 is driven by a mechanical drive, as has been indicated above. Specifically, the fluid delivery device 102 comprises a blower wheel 132, a housing 134 for rotatably receiving the blower wheel 132 therein, a support element 136 and a cam follower 138 (see FIG. 5), together forming the mechanical drive. The housing 134 comprises a mouthpiece 140 for adaptation to the mouth of a human or animal patient. The blower wheel 132 is provided with a cam 142.

[0222] The blower wheel 132 may be formed so as to be substantially symmetric or so as to exhibit at least a certain degree of asymmetry. In the latter case, the blower wheel 132 can be configured so as to provide a varying or alternating resistance to the exhalation or expiration flow of the user.

[0223] The blower wheel 132 serves as a flow energy converter which is configured to convert the exhalation or expiration flow through the mouth of the user of the fluid delivery device 102 into rotational movement. When the user exhales through the mouthpiece 140, the exhalation flow causes the blower wheel 132 to rotate and, subsequently, exits through a plurality of openings 144 provided in the housing 134.

[0224] The rotational movement of the blower wheel 132 is converted into linear or translational movement by the support element 136 and the cam follower 138, acting as a movement converter. Specifically, the cam follower 138 is slidably held by the support element 136, so as to be movable towards and away from the vibratable membrane 109. The cam 142 of the blower wheel 132 cooperates with the cam follower 138 so that rotation of the blower wheel 132 causes linear or translational movement of the cam follower 138. In this way, the cam follower 138 is periodically pushed against the vibratable membrane 109, thus deforming the membrane 109. When the cam follower 138 is moved away from the membrane 109, the membrane 109 returns to its initial position due to the restoring force thereof. Thus, the membrane 109 is caused to vibrate.

[0225] In the present embodiment, the cam follower 138 is brought into direct contact with the membrane 109, i.e., the mechanical drive is directly coupled to the membrane 109. Alternatively, these two components may be indirectly coupled to each other, e.g., by magnetic coupling.

[0226] Instead of the blower wheel 132, a fan wheel, an impeller, a turbine, an anemometer, such as a cup anemometer, or the like may be used to convert the exhalation or expiration flow of the user into rotational movement.

[0227] In the present embodiment, the oscillator 106 is controlled by the configurations and arrangements of the blower wheel 132, the housing 134, the support element 136 and the cam follower 138. These components thus form a mechanical control for controlling the oscillator 106. Specifically, the vibrator 108 is controlled by the mechanical control so as to impart vibrations to the resonator 110 at a resonance frequency of the resonator 110 or at a frequency which is within 20% of a resonance frequency of the resonator 110.

[0228] The mechanical drive of the present embodiment is detachably or removably attached to a remainder of the fluid delivery device 102. Hence, the mechanical drive can be separated from the remainder of the fluid delivery device 102 in a simple and efficient manner, thereby facilitating cleaning of the components of the device 102.

[0229] As an alternative or in addition to the mechanical drive used in the present embodiment, an electromagnetic drive, such as an electromagnetic linear drive or an electromagnetic rotational drive, may be employed.