DEVICE FOR DISPENSING A FLUID DROP-BY-DROP

Abstract

A device for dispensing a fluid drop-by-drop can include a fluid connector to supply the fluid to be dispensed, a pump which is fluidically connected to the fluid connector, an outlet nozzle which is fluidically connected to the pump, an actuating element, and a control unit. When the actuating element is actuated, the control unit activates the pump which pumps the supplied fluid to the outlet nozzle for dispensing drop-by-drop. The outlet nozzle has an outlet opening and a fluid channel which extends as far as the outlet opening and which, in the direction of the fluid from the pump as far as the outlet opening, has a first channel portion with a first cross-sectional surface and a second channel portion with a second cross-sectional surface adjoining the first channel portion. The second cross-sectional surface can be smaller than the first cross-sectional surface.

Claims

1. A device for dispensing a fluid drop-by-drop, comprising: a fluid connector that that supplies the fluid to be dispensed; a pump fluidically connected to the fluid connector; an outlet nozzle fluidically connected to the pump; an actuator; and a control unit that activates the pump when the actuator is actuated, wherein the pump pumps the supplied fluid to the outlet nozzle for dispensing drop-by-drop, wherein the outlet nozzle includes an outlet opening and a fluid channel which extends as far as the outlet opening and which, in the direction of the fluid from the pump as far as the outlet opening, includes a first channel portion with a first cross-sectional surface and a second channel portion with a second cross-sectional surface adjoining the first channel portion, and wherein the second cross-sectional surface is smaller than the first cross-sectional surface.

2. The device of claim 1, wherein the fluid channel includes a third channel portion adjoining the second channel portion, said third channel portion extending as far as the outlet opening and having a third cross-sectional surface which is larger than the second cross-sectional surface.

3. The device of claim 2, wherein the third channel portion extends in a linear manner.

4. The device of claim 2, wherein the outlet nozzle includes a replaceable end cap in which the third channel portion is configured.

5. The device of claim 2, wherein the outlet nozzle includes at the outlet opening a first region with a first external diameter, wherein a second region with a second diameter adjoins the first region in the direction counter to the direction of the fluid, wherein the second diameter is smaller than the first diameter.

6. The device of claim 2, 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 of claim 1, wherein an inner edge of the outlet opening is sharp-edged.

8. The device of claim 1, wherein the fluid channel of the outlet nozzle is configured such that a linear through-flow is prevented.

9. The device of claim 1, wherein a non-return valve is arranged in the fluid channel of the outlet nozzle, said non-return valve opening from a predetermined pressure of the fluid coming from the pump and thus producing a fluidic connection of the pump with the outlet opening.

10. The device of claim 1, wherein the pump is a diaphragm pump.

11. The device of claim 1, wherein a plurality of pump cycles of the pump are required in order to convey the volume of fluid for one droplet to be dispensed.

12. The device of claim 1, further comprising a temperature measuring device that measures the temperature of the fluid to be dispensed and forwards the measured temperature to the control unit, wherein the control unit varies the activation of the pump as a function of the measured temperature in order to compensate for a temperature-induced volume change of the conveyed volume.

13. The device of claim 1, wherein the pump comprises a motor and the control device, wherein when the pump is activated, the control device detects when the motor of the pump starts to rotate and from this time, after the defined time period for the operation of the pump has elapsed, actively brakes the motor of the pump.

14. The device of claim 1, further comprising an inclination sensor that measures the inclination of the device relative to a surface of the earth and forwards the inclination measurement to the control unit, wherein the control unit only activates the pump after the actuator is actuated, when the measured inclination is within a predetermined inclination range.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0037] FIG. 1 shows an isometric view of an exemplary embodiment of the device for dispensing according to certain embodiments.

[0038] FIG. 2 shows a sectional view of the device 1 of FIG. 1.

[0039] FIGS. 3 and 4 show schematic views for describing the mode of operation of a diaphragm pump.

[0040] FIG. 5 shows an enlarged sectional view of the detail A of FIG. 2.

[0041] FIG. 6 shows a sectional view along the section line B-B in FIG. 5.

DETAILED DESCRIPTION

[0042] In the exemplary embodiment shown in FIG. 1, for dispensing a fluid into an eye drop-by-drop, the device 1 according to the invention comprises a housing 2 with a main portion 3 and a grip portion 4. The grip portion 4 is configured such that a user may hold the device 1 by gripping around the grip portion 4 with one hand. Moreover, the grip portion 4 has a start button 5 for actuating the device 1. A dispensing region 6 is configured on the front end of the main portion 3. Moreover, on the upper region of the main portion 3 the device 1 has a connector 7, in the embodiment shown in FIG. 1 a container 8 with a fluid to be dispensed (in this case in the form of a medicine bottle) being fastened thereto.

[0043] A display 9 and two operating elements 10, 11 are provided at the rear end of the main portion 3.

[0044] As is visible most clearly in the sectional view in FIG. 2, a pump 12 which is connected via a first fluid connection 13 to the connector 7 and via a second fluid connection 14 to the dispensing region 6 is provided in the main portion 3. In this case, tubes are used for the two fluid connections 12 and 14.

[0045] The connector 7 has a piercing needle 15 by which a diaphragm 16 on the container 8 is pierced when the container 8 is attached, in order to ensure in this manner a connection of the fluid from the interior of the container 8 to the first fluid connection 13. The piercing needle 15 further comprises a valve which ensures an automatic ventilation of the container 8 and thus the required pressure compensation.

[0046] The pump 12 may be, for example, a diaphragm pump 12 which is designed for micro flow rates since the droplets to be dispensed are intended to have a volume of ca. 0.03 ml, for example.

[0047] The underlying principle of such a diaphragm pump 12 is described in more detail with reference to the schematic view of FIGS. 3 and 4. The pump 12 comprises a pump chamber 17 with a pump inlet 18 and a pump outlet 19 which in each case are closed by a non-return valve 20, 21. The non-return valves 20, 21 are arranged such that a flow of the fluid to be pumped is possible only from the pump inlet 18 into the pump chamber 17 and therefrom to the pump outlet 19. The pump chamber 17 is defined on one side by a diaphragm 22 which is formed, for example, from a flexible elastomer. The diaphragm 22 may be set in vibration by the pump 12 by means of a motor (not shown) via an eccentric (not shown), such that by a movement of the diaphragm 22 upwardly (arrow P1 in FIG. 3) the volume of the pump chamber 17 is increased and by a movement of the diaphragm 22 downwardly (arrow P2 in FIG. 4) the volume of the pump chamber 17 is reduced.

[0048] 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 suctioned 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 forced out of the pump chamber 17 to the pump outlet 19.

[0049] Moreover, a control unit S (FIG. 2) which, for example, has a processor and a memory is provided. The control unit S serves for controlling the pump 12, is connected to the start button 5 and the operating elements 10, 11 and generates the data and information which are shown on the display 9.

[0050] 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, by actuating the pump 12 fluid may be transported from the container 8 to the dispensing region 6.

[0051] The activation of the pump 12 is carried out via the actuation of the start button 5, wherein after the start button 5 has been actuated a predetermined number of pump cycles is carried out, due to the control by means of the control unit S, in order to convey the volume required for at least one droplet to be dispensed. An energy source 23 or a power supply 23 (in this case for example a rechargeable battery or a battery) is provided in the grip portion 4 for supplying energy to the pump 12 and the control unit S.

[0052] In order to prevent the volume of fluid conveyed by the pump 12 from being dispensed as a stream at the dispensing region 6 of the device 1, the outlet nozzle 24 shown in the enlarged sectional view in FIG. 5 is provided in the dispensing region 6. The outlet nozzle 24 has an inlet portion 25, which is connected to the second fluid connection 14, a first, second and third channel portion 26, 27, and 28, an outlet opening 29, as well as a non-return valve 30.

[0053] In the position shown in FIG. 5 of the non-return valve 30, this non-return valve closes the inlet portion 25.

[0054] From the application of a predetermined pressure (in this case for example 250 mbar) of the fluid conveyed by the pump 12, the non-return valve 30 is moved toward the outlet opening 29 so that it opens and the fluid may flow through the channel portions 26 to 28, as indicated by the arrows P3 and P4.

[0055] As may be further derived from the sectional view of the outlet nozzle 24 in FIG. 5 as well from the sectional view of FIG. 6, the cross-sectional surface of the second channel portion 27 is smaller than the cross-sectional surface of the first channel portion 26. The second channel portion 27 is formed by two channel sub-portions 27.sub.1 and 27.sub.2, each of which comprises a circle segment shaped cross section. The second channel portion 27 has a cross-sectional surface of 0.17 mm.sup.2 according to the present embodiment, whereas the cross section of the first channel section 26 is circular having a surface of 10.18 mm.sup.2. Moreover, the cross-sectional surface of the second channel portion 27 is also smaller than the cross-sectional surface of the third channel portion 28, wherein the cross section of the third channel section 28 is circular having a surface of 1.77 mm.sup.2. By this reduction in the cross-sectional surface, in combination with the non-return valve 30, a deceleration of the fluid flow which is generated by the pump 12 is achieved, whereby the fluid is dispensed in droplet form via the outlet opening 29 (not as a fluid stream). Thus, for example, the dispensing of the fluid into an eye (for example an animal eye) may be carried out drop-by-drop. Such a dispensing drop-by-drop may be used, for example, for vaccinating animals and thus for ocular vaccination. In this manner, for example, an ocular vaccination may be carried out on poultry. The device 1 according to the invention thus may also be denoted as an electronic hand-held appliance 1 for ocular vaccination.

[0056] Moreover, the outlet opening 29 has an edge shape of the inner edge 31 which is advantageous for the desired droplet break-off and thereby prevents the droplet from remaining suspended 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, a beveled edge is not provided at the distal end of the outlet opening 29. This sharp-edged characteristic of the outlet opening 29 promotes the droplet break-off since, as a result, the surface area is minimized and the fluid (or the liquid) adheres less easily to the outlet nozzle. In addition to the sharp-edged configuration of the inner edge 31 (the internal edge) of the outlet opening 29, the outer edge 35 at the distal end may also be configured to be sharp-edged (for example without a beveled edge). This also promotes the droplet break-off. “Sharp-edged” is understood to mean here that the material boundary surfaces abutting the respective edge enclose an angle ranging from 80° to 100° and preferably ranging from 85° to 95° and particularly preferably of 90°. Moreover, the outer edge 35 is preferably configured without a beveled edge.

[0057] Additionally, an outer groove 36 (reduction in the external diameter at the distal end in the region of the third channel portion 28) is provided, said outer groove preventing the fluid or the liquid from running along the outlet nozzle 24, which would lead to an undesired increase in the contact surface area. The outer groove 36 is also advantageous for the desired droplet break-off. By means of the groove 36, the outlet nozzle 24 has at the outlet opening 29 a first region 37 with a first diameter and a second region 38 with a second external diameter adjoining the first region 37 in the direction counter to the direction of the fluid, wherein the second external diameter is smaller than the first external diameter.

[0058] As shown in FIG. 5 the outlet nozzle 24 may have a replaceable end cap 32 which comprises the third channel portion 28. To this end, the end cap 32 may be configured, for example, to be screwable.

[0059] Since the internal diameter or the cross-sectional surface of the third channel portion 28 influences the droplet size, a plurality of end caps 32 with different third channel portions 28 which differ in the cross-sectional surface thereof or in the internal diameter may be provided. By selecting the respectively suitable end cap 32, therefore, the desired droplet size may be adjusted thereby.

[0060] Moreover, the device 1 may have a temperature sensor 33 (see FIG. 2) which measures the temperature of the fluid immediately upstream of the outlet nozzle 24. The measurement signal or the measurement 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, therefore, the control unit S may carry out changes in the activation of the pump 12 after the start button 5 has been actuated, if this is required. Thus, for example, the viscosity of medicines and vaccines changes with the temperature, which may be compensated, for example, by longer or shorter pumping times so as always to generate the same droplet size. It may also be necessary that a dispensing drop-by-drop is desired only beyond a certain temperature of the fluid. In this case, for example, a dispensing may be prevented below the predetermined temperature by the control unit S and/or the measured fluid temperature may be shown on the display 9.

[0061] Moreover, the device 1 may 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 surface of the earth. The control unit S may be designed such that an activation of the pump 12 takes place after the start button 5 has been actuated only when the inclination of the device 1 measured at this moment in time has a predetermined value or is within a predetermined range. Thus, for example, it may be the case that the device 1 is designed for dispensing drop-by-drop at an inclination of 35°. In this case, the control unit may be designed, for example, such that dispensing is only possible when the measured inclination deviates by no more than ±1°, ±2°, ±3°, ±4°, ±5° or ±6° from the predetermined inclination (in this case 35°). This also serves to ensure a reproducible droplet size.

[0062] The device 1 may be designed such that it is communicated to the user acoustically, haptically and/or optically whether the inclination of the device 1 is within the permitted range or outside the permitted range.