DEVICE FOR DROP-BY-DROP DISPENSING OF A FLUID

Description

[0001] The present invention relates to a device for the dropwise dispensing of a fluid having the features of the preamble of claim 1.

[0002] If the fluid is, for example, a vaccine, such a device can be used to deliver the vaccine drop by drop.

[0003] For example, it would be desirable to dispense eye drops to poultry for ocular vaccination. Currently, such ocular vaccination is performed using a plastic bottle. By manually applying pressure to the bottle wall, a drop is created at an outlet nozzle. Once the drop has dispersed, the pressure is released, so that the remaining vaccine is drawn back into the bottle by the resulting negative pressure. The size and number of drops depend on both the pressure exerted by the user and the angle at which the bottle is held when dispensing the drops.

[0004] In practical application for ocular vaccination of an animal, for example, it may happen that two or more drops are released, as a large number of animals usually have to be treated under extreme time pressure. This creates user-related variability, which leads to fluctuations in dosage on the one hand, and a difficult-to-calculate vaccine requirement for a quantitatively defined animal population on the other.

[0005] WO 2012 / 159026 A1 and WO 2011 / 126569 A1 each show a device for the dropwise dispensing of a fluid of the type mentioned above. US 4 623 337 A shows a device for the dropwise dispensing of a fluid which does not have a pump but is to be operated manually.

[0006] On this basis, a device for the dropwise dispensing of a fluid of the type mentioned at the outset is to be further developed in such a way that the difficulties described can be overcome as completely as possible.

[0007] The invention is defined in claim 1. Advantageous further developments are specified in the dependent claims.

[0008] Because the pump is actuated by the actuating element, a defined amount of fluid can always be delivered to the outlet opening, ensuring the desired droplet size and number. Droplet formation is particularly ensured by the fact that the fluid channel tapers toward the outlet surface, as the second cross-sectional area is smaller than the first cross-sectional area.

[0009] The device can be designed in particular such that actuation of the actuating element, which can be implemented as a push button, for example, causes the pump to run for a defined time, so that a defined amount of fluid is pumped to the outlet opening. Several pump cycles of the pump may be necessary to deliver the amount of fluid for one drop. If the fluid is a medication or a vaccine, for example, a drop size of 0.03 ml may be desired. This may require several pump cycles (e.g., four). The pump can, for example, be a diaphragm pump.

[0010] The device can have an input module (for example with a display and one or more input elements) via which, for example, the drop size and / or the number of drops generated upon single actuation of the actuating element can be adjusted.

[0011] Preferably, the device is designed such that when the actuating element is actuated once, exactly one single drop is formed and released.

[0012] The device may include a counter that counts the total number of drops dispensed. This number may be displayed, for example, on the display.

[0013] Furthermore, the device can comprise a temperature measuring device for measuring the temperature of the fluid to be pumped. This can be a temperature sensor that measures, for example, the fluid in the fluid connection to the pump or the fluid in the fluid connection from the pump to the fluid connection (preferably at a defined location). The measured temperature can, for example, be shown on the display to inform the user and / or can be used to issue a warning if a definable threshold is exceeded or undershot or if the measured temperature lies outside a definable interval.

[0014] The measured temperature can be fed to a control unit of the device for dropwise dispensing of a fluid, which, depending on the temperature, adjusts, for example, the motor running time when the actuating element is actuated to ensure that the same amount of fluid is delivered or pumped. For example, as the temperature rises, the viscosity of the fluid may increase, resulting in a longer pumping time to deliver the same amount of fluid.

[0015] The measured temperature can also be used in a calibration mode of the device to adjust the pump running time.

[0016] Furthermore, the fluid channel can have a third channel section adjoining the second channel section, extending to the outlet opening and having a third cross-sectional area that is larger than the second cross-sectional area. This promotes droplet formation. Furthermore, the third channel section can be cylindrical, in particular, with its diameter adapted to the desired droplet size.

[0017] Thus, the outlet nozzle may have an interchangeable end cap with the third channel section, so that different end caps with different diameters or cross-sectional areas of the third channel section can be provided, from which the end cap is selected in each case which has the desired diameter (or the desired cross-sectional area) of the third channel section for the required droplet size.

[0018] The outlet nozzle can have a first region with a first outer diameter at the outlet opening and a second region with a second outer diameter adjoining it in the direction opposite to the fluid flow direction, wherein the second outer diameter is smaller than the first outer diameter. The first region preferably ends at the distal end of the outlet nozzle. This creates an external recess, which is advantageous for the desired droplet detachment at the outlet opening.

[0019] Furthermore, the inner edge of the outlet opening can be sharp-edged. Furthermore, the outer edge of the outlet opening can be sharp-edged. Sharp-edged is understood here in particular to mean that no chamfer is formed and / or that the material interfaces abutting at the respective edge enclose an angle in the range of 80° to 100°, preferably in the range of 85° to 95°, and particularly preferably an angle of 90°.

[0020] For a 0.03 ml drop, the third channel section, which preferably has a circular cross-section, has a diameter of, for example, 1.5 mm. The diameter can range from 0.5 mm to 3 mm (preferably up to 2 mm). The cross-sectional area of ​​the third channel section can range from 0.20 to 7.07 mm². With increasing drop size, the optimal diameter of the third channel section increases.

[0021] The first channel section, which preferably has a circular cross-section, can have a diameter of, for example, 3 to 6 mm. The cross-sectional area of ​​the first channel section can be in the range of 7.07 to 28.27 mm2.

[0022] The second channel section may have one, two, or more second channel subsections, which, for example, have a circular segment-shaped cross-section. The cross-sectional area of ​​the second channel section may be in the range from 0.05 to 1 mm 2 , preferably in the range from 0.1 to 0.5 mm 2 , and particularly preferably in the range from 0.15 to 0.30 mm 2 .

[0023] The third cross-sectional area may in particular be smaller than the first cross-sectional area.

[0024] The second channel section preferably connects directly to the first channel section. Furthermore, the third channel section preferably connects directly to the second channel section.

[0025] With the device according to the invention, drops with a volume of 0.025 ml to 0.04 ml can be produced.

[0026] For example, 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100 drops can be generated per minute. While generating exactly one drop per actuation of the actuator, this number is essentially limited by how quickly the actuator can be repeatedly actuated.

[0027] It has been shown that improved droplet formation can be achieved if the fluid channel of the outlet nozzle is designed in such a way that straight-line flow is prevented.

[0028] Furthermore, it is advantageous if a check valve is arranged in the fluid channel of the outlet nozzle. This check valve opens at a predetermined pressure of the fluid coming from the pump, thus establishing a fluid connection between the pump and the outlet opening. This can slow down the speed of the pumped fluid, which in turn contributes to droplet formation and, in particular, prevents the fluid from being discharged as a jet. This check valve therefore primarily serves to ensure droplet formation.

[0029] The device has an inclination sensor that measures the current inclination of the device and thus of the outlet nozzle relative to the earth's surface and transmits it to the control unit. The device is further designed such that actuating the actuating element only activates the pump when the measured inclination lies within a predetermined inclination range. This can be, for example, an inclination range of 30 to 40°. If a user holds the device at this inclination, they can dispense the desired number of drops by actuating the actuating element. The device can be designed such that it informs the user acoustically, haptically, and / or visually whether they are holding the device such that the inclination is within the predetermined inclination range or not.

[0030] To adjust the volume, the control unit can detect when a pump motor starts to rotate after the pump has been activated by operating the actuating element. This point in time is not the same for every actuation of the actuating element, but depends on external influencing factors, such as the resistance against which the motor must start. From this point on, the pump is supplied with voltage for a defined period of time, and at the end of the period of time the pump motor is actively braked. This ensures that the indefinable influences of motor start-up time and motor run-down time are minimized. Active braking can be achieved, for example, by reversing the direction of rotation of the motor at the end of the period of time so that the motor attempts to rotate the motor shaft in the opposite direction.

[0031] The device according to the invention is preferably calibrated. The user can carry out the calibration using simple means. The user can select a calibration mode via the input unit, whereby a specific target volume is specified, for example for a certain medication. Alternatively, the user can select or specify a target volume. Once this is complete, the user actuates the actuating element until the defined target volume has been dispensed into a vessel. The control unit of the device determines the optimal active pump running time based on the number of actuations required until the target volume is reached. This type of calibration can compensate for external influences on the pump's delivery behavior. These can include, for example, the type of fluid, the temperature of the fluid or the preload of the check valve in the fluid channel of the outlet nozzle.The preload of the check valve in particular varies due to unavoidable manufacturing tolerances.

[0032] The fluid to be delivered can, in particular, be a liquid. Preferably, the fluid can be a medication, an active ingredient, or a vaccine. Dropwise delivery by means of the device can be used for delivery into an eye, a body orifice, or onto the skin of an animal (e.g., poultry).

[0033] A fluid reservoir can be connected to the fluid port. This could be a container containing the fluid, such as a medication bottle. However, a hose connection to a stationary reservoir is also possible.

[0034] The device according to the invention is designed, in particular, as a portable device. The device according to the invention can have a housing with a handle portion that can preferably be held with one hand. The actuating element can be provided on the handle portion. In particular, it can be designed such that a user can operate the actuating element with the index finger of the hand holding the handle portion.

[0035] A method for dispensing a fluid drop by drop is further provided, wherein a device is used having a fluid connection via which the fluid to be dispensed can be supplied, a pump which is in fluid connection with the fluid connection, an outlet nozzle which is in fluid connection with the pump, and an actuating element which, when actuated, activates the pump, which pumps supplied fluid to the outlet nozzle for drop by drop dispensing, wherein the outlet nozzle has an outlet opening and a fluid channel extending to the outlet opening, which in the fluid direction in the pump up to the outlet opening has a first channel section with a first cross-sectional area and a second channel section adjoining the first channel section with a second cross-sectional area, wherein the second cross-sectional area is smaller than the first cross-sectional area, wherein the actuating element is actuated to dispense a drop.

[0036] The method can be developed in the same way as the device according to the invention.

[0037] It is understood that the features mentioned above and those to be explained below can be used not only in the combinations indicated, but also in other combinations or in isolation, without departing from the scope of the present invention.

[0038] The invention is explained in more detail below using exemplary embodiments with reference to the accompanying drawings, which also disclose features essential to the invention. These exemplary embodiments are for illustrative purposes only and are not to be interpreted as restrictive. For example, a description of an exemplary embodiment with a large number of elements or components should not be interpreted as meaning that all of these elements or components are necessary for implementation. Rather, other exemplary embodiments may also contain alternative elements and components, fewer elements or components, or additional elements or components. Elements or components of different exemplary embodiments may be combined with one another unless otherwise stated. Modifications and variations described for one of the exemplary embodiments may also be applicable to other exemplary embodiments.To avoid repetition, identical or corresponding elements in different figures are designated by the same reference numerals and are not explained more than once. The figures show: . Fig. 1 is an isometric view of an embodiment of the device 1 according to the invention for dispensing a dropwise dispensing of a fluid; Fig. 2 is a sectional view of the device 1 of Fig. 1 ; Fig. 3 and 4 schematic representations to explain the operation of a diaphragm pump; Fig. 5 an enlarged sectional view of detail A of Fig. 2 and Fig. 6 a sectional view along the section line BB in Fig. 5 .

[0039] In the Fig. 1 In the embodiment shown, the device 1 according to the invention for the dropwise delivery of a fluid into an eye comprises a housing 2 with a main section 3 and a handle section 4. The handle section 4 is designed such that a user can hold the device 1 by grasping the handle section 4 with one hand. Furthermore, the handle section 4 has a start button 5 for actuating the device 1. At the front end of the main section 3, a delivery area 6 is formed. Furthermore, the device 1 has a connection 7 at the upper area of ​​the main section 3, to which in the Fig. 1 In the embodiment shown, a container 8 with the fluid to be dispensed (here in the form of a medicine bottle) is attached.

[0040] At the rear end of the main section 3 there is a display 9 and two control elements 10, 11.

[0041] As best seen in the section view in Fig. 2 As can be seen, a pump 12 is provided in the main section 3, which is connected to the connection 7 via a first fluid connection 13 and to the discharge area 6 via a second fluid connection 14. Hoses are used here for the two fluid connections 12 and 14.

[0042] The connection 7 has a piercing mandrel 15, which pierces a membrane 16 on the container 8 when the container 8 is secured, thus ensuring a connection for the fluid from the interior of the container 8 to the first fluid connection 13. The piercing mandrel 15 further comprises a valve that ensures the automatic venting of the container 8 and thus the necessary pressure equalization.

[0043] The pump 12 may, for example, be a diaphragm pump 12 designed for micro flow rates, since the drops to be dispensed should, for example, have a volume of approximately 0.03 ml.

[0044] The basic principle of such a diaphragm pump 12 is explained with reference to the schematic diagram in the Fig. 3 und 4 explained in more detail. The pump 12 comprises a pump chamber 17 with a pump inlet 18 and a pump outlet 19, each of which is closed by a check valve 20, 21. The check valves 20, 21 are arranged such that only a flow of the fluid to be pumped from the pump inlet 18 into the pump chamber 17 and from there to the pump outlet 19 is possible. The pump chamber 17 is delimited on one side by a diaphragm 22, which is formed, for example, from a flexible elastomer. The diaphragm 22 can be set into vibration by the pump 12 by a motor (not shown) via an eccentric (not shown) such that a movement of the diaphragm 22 upwards (arrow P1 in Fig. 3 ) the volume of the pump chamber 17 is increased and by a downward movement of the membrane 22 (arrow P2 in Fig. 4 ) the volume of the pump chamber 17 is reduced.

[0045] When increasing the volume of the pump chamber 17 according to Fig. 3 a negative pressure is generated in the pump chamber 17, whereby fluid is sucked into the pump chamber 17 via the pump inlet 18. When the volume of the pump chamber 17 is reduced ( Fig. 4 ) an overpressure is generated, whereby fluid is pushed from the pump chamber 17 to the pump outlet 19.

[0046] Furthermore, a control unit S ( Fig. 2 ) is provided, which, for example, has a processor and a memory. The control unit S serves to control the pump 12, is connected to the start button 5 and the control elements 10, 11, and generates the data and information shown on the display 9.

[0047] Since in the device 1 according to the invention the first fluid connection 13 is connected to the pump inlet 18 and the second fluid connection 14 is connected to the pump outlet 19, fluid can be transported from the container 8 to the dispensing area 6 by actuating the pump 12.

[0048] The pump 12 is activated by pressing the start button 5. After pressing the start button 5, a predetermined number of pumping cycles are performed, controlled by the control unit S, in order to deliver the necessary volume for at least one drop to be dispensed. To supply energy to the pump 12 and the control unit S, an energy source 23 or a power supply 23 (here, for example, a rechargeable battery or a battery) is provided in the handle section 4.

[0049] In order to prevent the fluid volume delivered by the pump 12 from being discharged as a jet at the discharge area 6 of the device 1, the device shown in the enlarged sectional view in Fig. 5 The outlet nozzle 24 shown is provided in the discharge area 6. The outlet nozzle 24 has an inlet section 25 connected to the second fluid connection 14, a first, second and third channel section 26, 27 and 28, an outlet opening 29 and a check valve 30.

[0050] In the Fig. 5 In the position shown, the check valve 30 closes the inlet section 25.

[0051] When a predetermined pressure (here, for example, 250 mbar) of the fluid delivered by the pump 12 is applied, the check valve 30 is moved towards the outlet opening 29 so that it opens and the fluid can flow through the channel sections 26 to 28, as indicated by the arrows P3 and P4.

[0052] As shown in the sectional view of the outlet nozzle 24 in Fig. 5 and the sectional view in Fig. 6 As can also be seen, the cross-sectional area of ​​the second channel section 27 is smaller than the cross-sectional area of ​​the first channel section 26. The second channel section 27 is formed by two channel sub-sections 27 1 and 27 2 , each having a circular segment-shaped cross-section, and in the embodiment described here has a cross-sectional area of ​​0.17 mm 2<, whereas the cross-section of the first channel section 26 is circular with an area of ​​10.18 mm 2<. Furthermore, the cross-sectional area of ​​the second channel section 27 is also smaller than the cross-sectional area of ​​the third channel section 28, the cross-section of the third channel section 28 being circular with an area of ​​1.77 mm 2<.This reduction in the cross-sectional area, in conjunction with the check valve 30, slows down the fluid flow generated by the pump 12, whereby the fluid is delivered in droplet form via the outlet opening 29 (not as a fluid jet). This allows, for example, the fluid to be delivered dropwise into an eye (e.g., an animal's eye). Such dropwise delivery can be used, for example, to vaccinate animals and thus for ocular vaccination. In this way, for example, ocular vaccination of poultry can be carried out. The device 1 according to the invention can therefore also be referred to as an electronic handheld device 1 for ocular vaccination.

[0053] Furthermore, the outlet opening 29 has an edge shape of the inner edge 31 which is advantageous for the desired droplet break-off and thus prevents the droplet from getting stuck on the outlet nozzle 24. In particular, the edge shape of the inner edge 31 is selected such that it is as sharp-edged as possible and, for example, no chamfer is provided at the distal end of the outlet opening 29. This sharp edge of the outlet opening 29 promotes droplet break-off because it minimizes the surface area and the fluid (or liquid) adheres less well to the outlet nozzle. In addition to the sharp-edged design of the inner edge (inner rim) 31 of the outlet opening 29, the outer edge 35 at the distal end can also be sharp-edged (e.g. without a chamfer). This also promotes droplet break-off."Sharp-edged" is understood here in particular to mean that the material interfaces that meet at the respective edge enclose an angle in the range of 80° to 100°, preferably in the range of 85° to 95°, and particularly preferably 90°. Furthermore, the outer edge 35 is preferably formed without a chamfer.

[0054] Additionally, an external recess 36 (reduction in the outer diameter at the distal end in the region of the third channel section 28) is provided, which prevents the fluid or liquid from running along the outlet nozzle 24, which would lead to an undesirable increase in the contact surface. The external recess 36 is also advantageous for the desired droplet break-off. Due to the recess 36, the outlet nozzle 24 has a first region 37 with a first diameter at the outlet opening 29 and a second region 38 with a second outer diameter, adjoining the first region 37 in the direction opposite to the fluid direction, wherein the second outer diameter is smaller than the first outer diameter.

[0055] The outlet nozzle 24 can, as in Fig. 5 shown, have a replaceable end cap 32 which encloses the third channel section 28. For this purpose, the end cap 32 can be designed, for example, to be screwable.

[0056] Since the inner diameter or cross-sectional area of ​​the third channel section 28 influences the droplet size, several end caps 32 with different third channel sections 28, which differ in their cross-sectional area or inner diameter, can be provided. By selecting the appropriate end cap 32, the desired droplet size can be adjusted.

[0057] Furthermore, the device 1 can have a temperature sensor 33 ( Fig. 2 ) which measures the temperature of the fluid shortly before the outlet nozzle 24. The measurement signal or the measured variable is communicated to the control unit S, since the temperature sensor 33 is connected to the control unit S. Depending on the measured temperature, the control unit S can then, if necessary, make changes to the control of the pump 12 after the start button 5 has been pressed. For example, the viscosity of medications and vaccines changes with temperature, which can be compensated for by longer or shorter pumping times in order to still produce drops of the same size. It may also be necessary that drop-by-drop dispensing is only desired above a certain fluid temperature. In this case, for example, dispensing below the predetermined temperature can be prevented by the control unit S and / or the measured fluid temperature can be shown on the display 9.

[0058] Furthermore, the device 1 can have an inclination sensor 34 ( Fig. 2 ), which is also connected to the control unit S. The inclination sensor 34 measures the inclination of the device and thus of the outlet nozzle 24 relative to the earth's surface. The control unit S can be designed such that activation of the pump 12 after actuation of the start button 5 only occurs if the inclination of the device 1 measured at that moment has a predetermined value or lies within a predetermined range. For example, the device 1 can be designed to dispense drops at an inclination of 35°. In this case, the control unit can be designed such that dispensing is only possible if the measured inclination does not deviate by more than ± 1°, ± 2°, ± 3°, ± 4°, ± 5° or ± 6° from the predetermined inclination (here 35°). This also serves to ensure a reproducible drop size.

[0059] The device 1 can be designed in such a way that the user is informed acoustically, haptically and / or visually whether the inclination of the device 1 is within the permissible range or outside the permissible range.

Claims

1. A device for dispensing a fluid drop-by-drop, wherein the device has a fluid connector (7), the fluid to be dispensed being able to be supplied thereby, a pump (12) which is fluidically connected to the fluid connector (7), an outlet nozzle (24) which is fluidically connected to the pump (12), an actuating element (5), and a control unit (S) which, when the actuating element (5) is actuated, activates the pump (12) which pumps the supplied fluid to the outlet nozzle (24) for dispensing drop-by-drop, wherein the outlet nozzle (24) has an outlet opening (29) and a fluid channel which extends as far as the outlet opening and which, in the direction of the fluid from the pump (12) as far as the outlet opening (29), has a first channel portion (26) with a first cross-sectional surface and a second channel portion (27) with a second cross-sectional surface adjoining the first channel portion (26), wherein the second cross-sectional surface is smaller than the first cross-sectional surface, characterized in that an inclination sensor (34) is provided, said inclination sensor measuring the inclination of the device (1) relative to the surface of the earth and forwarding this measurement to the control unit (S), wherein the control unit (S) only activates the pump (12) after the actuating element (5) is actuated, when the measured inclination is within a predetermined inclination range.

2. The device as claimed in claim 1, wherein the fluid channel has a third channel portion (28) adjoining the second channel portion (27), said third channel portion extending as far as the outlet opening (29) and having a third cross-sectional surface which is larger than the second cross-sectional surface.

3. The device as claimed in claim 2, wherein the third channel portion (28) extends in a linear manner.

4. The device as claimed in claim 2 or 3, wherein the outlet nozzle (24) has a replaceable end cap (32) in which the third channel portion (28) is configured.

5. The device as claimed in one of claims 2 to 4, wherein the outlet nozzle (24) has at the outlet opening (29) a first region (37) with a first external diameter, wherein a second region (38) with a second diameter adjoins the first region (35) in the direction counter to the direction of the fluid, wherein the second diameter is smaller than the first diameter.

6. The device as claimed in one of the above claims, wherein the third cross-sectional surface of the third channel portion is smaller than the first cross-sectional surface of the first channel portion.

7. The device as claimed in one of the above claims, wherein the inner edge (31) of the outlet opening (29) is configured to be sharp-edged.

8. The device as claimed in one of the above claims, wherein the fluid channel of the outlet nozzle (24) is configured such that a linear through-flow is prevented.

9. The device as claimed in one of the above claims, wherein a non-return valve (30) is arranged in the fluid channel of the outlet nozzle (24), said non-return valve opening from a predetermined pressure of the fluid coming from the pump (12) and thus producing a fluidic connection of the pump (12) with the outlet opening (29).

10. The device as claimed in one of the above claims wherein the pump (12) is configured as a diaphragm pump.

11. The device as claimed in one of the above claims, wherein a plurality of pump cycles of the pump (12) are required in order to convey the volume of fluid for one droplet to be dispensed.

12. The device as claimed in one of the above claims, wherein a temperature measuring device (33) is provided, said temperature measuring device measuring the temperature of the fluid to be dispensed and forwarding this temperature to the control unit (S) which varies the activation of the pump (12) as a function of the measured temperature, in order to compensate for a temperature-induced volume change of the conveyed volume.

13. The device as claimed in one of the above claims, wherein the pump (12) has a motor and the control device (S), when the pump (12) is activated, detects when the motor of the pump (12) starts to rotate and from this time, after the defined time period for the operation of the pump (12) has elapsed, actively brakes the motor of the pump (12).