DEVICE AND METHOD FOR THE METERED DISPENSING OF A LIQUID

Abstract

A device and a method for the metered dispensing of a liquid for the purpose of releasing an active substance in a human or animal body, and to a use of a device. A device for the metered delivery of a liquid for the purpose of releasing an active substance in a human or animal body comprises a metering apparatus for metering a defined volume of a liquid, an inlet in fluidic communication with the metering apparatus for supplying liquid into the metering apparatus and an outlet in fluidic communication with the metering apparatus for dispensing the defined volume of the liquid. The metering apparatus comprises a wall which encloses a metering cavity for receiving the liquid. By means of manual pressure on the wall, the metering cavity may be reduced, so that the defined volume of the liquid is delivered from the metering cavity to the outlet.

Claims

1. A device for the metered delivery of a liquid for the purpose of releasing an active substance in a human or animal body, comprising a metering apparatus for metering a defined volume of a liquid, an inlet in fluidic communication with the metering apparatus for supplying liquid to the metering apparatus and an outlet in fluidic communication with the metering apparatus for delivering the defined volume of the liquid, wherein the metering apparatus comprises a wall which encloses a metering cavity for receiving the liquid, wherein the metering cavity can be reduced by manual pressure on the wall, such that the defined volume of the liquid is conveyed from the metering cavity to the outlet.

2. The device according to claim 1, wherein the wall is designed such that at least one region of the wall is elastically deformed by the manual pressure and the wall returns at least substantially to its original shape by an elastic restoring force after the manual pressure ceases.

3. The device according to claim 1, wherein the metering apparatus comprises a first check valve that prevents flow of the liquid from the metering cavity to the inlet, and a second check valve that prevents flow of the liquid from the outlet to the metering cavity.

4. The device according to claim 1, wherein the device additionally comprises a supply cavity for receiving a supply of the liquid to be metered, wherein the supply cavity is in fluidic communication with the inlet, wherein a volume of the supply cavity is greater, in particular at least by a factor of 2, preferably a factor of 5, than a volume of the metering cavity.

5. The device according to claim 1, wherein the supply cavity is formed by a wall which is elastically deformable at least in some regions, so that the supply cavity decreases as the supply of the liquid decreases.

6. The device according to claim 5, wherein the elastic restoring force of the metering cavity is greater than an elastic restoring force of the supply cavity.

7. The device according to claim 4, wherein at least one region of the wall of the supply cavity is designed such that a cannula can pierce through the wall of the supply cavity, in order to introduce liquid into the supply cavity with the cannula.

8. The device according to claim 1, wherein the device has a nonpierceable element, so that undesired piercing of a rear region of the wall of the supply cavity is prevented.

9. The device according to claim 1, wherein the nonpierceable element is a nonpierceable plate (26) made of a biocompatible material, which is arranged at least partially in the supply cavity.

10. The device according to claim 1, wherein the device has a maximum height (H) less than 13 mm, in particular less than 10 mm.

11. The device according to claim 1, wherein a width (B) of the device is greater by at least a factor of 3 than a height (H) of the device and/or in that a length (L) of the device is greater by at least a factor of 5 than a height (H) of the device.

12. The device according to claim 1, wherein the wall of the metering cavity is convex at least in some regions.

13. A method for metered delivery of a liquid for the purpose of releasing an active substance in a human or animal body using a device according to claim 1, wherein by manual pressure on the wall, the metering cavity is reduced so that a defined volume of the liquid is delivered from the metering cavity to the outlet.

14. The method according to claim 1, wherein the device is implanted under the skin in a human or animal body.

15. A use of a device according to claim 1 for the metered delivery of a liquid for the purpose of releasing an active substance in a human or animal body, wherein the device is implanted under the skin, in particular in a human or animal body.

Description

BRIEF DESCRIPTION

[0048] Exemplary embodiments of the invention are also explained in more detail below with reference to figures. Features of the exemplary embodiments can be combined individually or in a plurality with the claimed objects, unless otherwise indicated. The claimed areas of protection are not limited to the exemplary embodiments.

[0049] Shown are:

[0050] FIG. 1: a perspective view of a device according to the invention,

[0051] FIG. 2: a plan view of a device according to the invention,

[0052] FIG. 3: a side view of a device according to the invention;

[0053] FIG. 4: a sectional drawing of a device according to the invention while performing a method step,

[0054] FIG. 5: a sectional drawing of a device according to the invention while performing an additional method step;

[0055] FIG. 6 an enlarged detail from FIG. 5,

[0056] FIG. 7 a perspective view of a device according to the invention,

[0057] FIG. 8 a sectional drawing of a device according to the invention while filling, and

[0058] FIG. 9 a sectional drawing of a device according to the invention after filling.

DETAILED DESCRIPTION

[0059] FIG. 1 shows a device 10 for the metered dispensing of a liquid for the purpose of releasing an active substance in a human or animal body. The device 10 comprises a housing 37 in which a metering apparatus 14 is accommodated. The metering apparatus 14 comprises a metering cavity 20, which is delimited at the top by an elastic wall 21. By manually pressing with a finger 40 on the wall 21, a defined volume of a liquid from the metering cavity 20 can be output from an outlet 18 of the device. A conduit element, namely a tube 35, through which the metered volume can be guided to a target position, is connected to the outlet 18.

[0060] As an inlet, the metering cavity 20 comprises a fluidic connection to a supply cavity 22, which is likewise accommodated in the housing 37. The supply cavity 22 is also delimited upward by an elastic wall 23. After the liquid has been metered, liquid can therefore flow out of the supply cavity 22 into the metering cavity 20, in order to allow renewed metering.

[0061] FIG. 2 shows a plan view, and FIG. 3 shows a side view. It can be seen that both the width B and the length L of the device 10 are significantly larger than the height H of the device 10. The width B of the device 10 is greater by a factor of between 5 and 6 than the height H of the device. The length L of the device 10 is greater by a factor between 8 and 9 than the height H of the device. The height H of the device is between 5 mm and 7 mm. Overall, the device 10 is flat, plate-shaped and compact, in order to allow implantation under the skin of a patient. The usable volume of the supply cavity 22 is, in particular, greater by a factor between 6 and 10 than the usable volume of the metering cavity 20, so that 6 to 10 dosage operations are possible.

[0062] FIGS. 4 and 5 show a possible layout and use of the device 10 in a longitudinal section. The metering apparatus 14 with the metering cavity 20 and inlet 16 and outlet 18 are shown. The supply cavity 22 is connected to the inlet 16. A tube connection 34 with a tube 35 connected thereto is located at the outlet 18. A first check valve 31 allows a flow of liquid from the supply cavity 22 through the inlet 16 into the metering cavity 20, but not in the opposite direction. A second check valve 32 allows a flow of liquid from the metering cavity 20 to the outlet 18, but not in the opposite direction. This ensures that the direction of flow of the liquid is always as intended. Penetration of metered liquid or bodily fluid into the device is prevented.

[0063] The housing 37 of the device comprises a base plate 38 and outer and central upper housing parts. The housing 37 is produced from a comparatively stiff plastics material. The upper regions of the wall 21 of the metering cavity 20 and the wall 23 of the supply cavity 22, which are fastened to the housing 37, are produced from an elastic material and are accordingly deformable.

[0064] The elastic wall 23 of the supply cavity 22 is designed such that it can be pierced by a cannula, in order to introduce liquid 12 into the supply cavity 22. This is shown in FIGS. 7 to 9, which will be discussed below. The device 10 additionally comprises a nonpierceable element 25, which prevents undesired piercing of the base plate 38. The nonpierceable element 25 is formed as a nonpierceable plate 26 made of a biocompatible metal material, which is arranged on the upper side of the base plate 38 in the interior of the supply cavity 22. The device can therefore be shown in an X-ray. The upper side of the nonpierceable plate 26 is preferably coated with silver.

[0065] FIG. 4 shows a state in which both the metering cavity 20 and the supply cavity 22 are filled with the liquid 12. The particular flexible walls 21 and 23 are each curved convexly upward. This makes it possible to very easily feel the metering cavity 20 and therefore the point at which the manual pressure is to be applied.

[0066] FIG. 5 shows a subsequent state in which liquid 12 is discharged through the outlet 18, the tube connection 34 and the tube 35 by manually pressing a finger 40 onto the wall 21 of the metering cavity 20. The first check valve 31 is blocked, so that no liquid can flow from the metering cavity 20 into the supply cavity 22. By contrast, the second check valve 32 is open, so that the liquid can reach the outlet 18 from the metering cavity 20.

[0067] On the one hand, the convex curvature of the metering cavity 20 and therefore its volume is reduced in FIG. 5 in contrast to FIG. 4. This can be additionally continued by further pressing down a finger 40 until an end point is reached, for example when the wall 21 touches the base plate 38 at least in the middle. In other words, the metering cavity 20 is reduced to convey the defined volume of the liquid 12 from the metering cavity 20 to the outlet 18. In this case, the defined volume of the liquid 12 was then metered. On the other hand, the convex curvature of the supply cavity 22 and therefore its volume is also reduced. This can be the case, for example, because one or more dosing operations have already been carried out beforehand.

[0068] After metering has taken place, the finger 40 can be removed. Due to the elastic restoring force of the wall 21, a negative pressure is generated in the metering cavity 20, which causes the first check valve 31 to be opened. In this way, liquid 12 can flow out of the supply cavity 22 into the metering cavity 20. In so doing, the wall 23 of the supply cavity 22 can be deformed.

[0069] FIG. 6 shows an enlarged detail of FIG. 5. It can be seen that the valve body 33 of the first check valve is in its closed position. It is pressed to the left against a valve housing by the force of a compression spring arranged on the right in the valve and, if applicable, additionally by the pressure of the liquid 12 inside the metering cavity 20, and therefore blocks the flow through the valve. In contrast, the valve body 33 of the second check valve 32 is in an open position. As a result of the pressure of the liquid 12 in the interior of the metering cavity 20, the valve body 33 is pressed to the right against the force of the pressure spring arranged on the right in the valve, so that a gap is produced on the left side between the valve body 33 and the valve housing, through which gap the liquid 12 can flow past the valve body 33 and out through the outlet 18.

[0070] FIG. 7 shows the device 10 according to the invention before filling the supply cavity 22 with liquid. A pen 28 with a cannula 29 is arranged directly above the pierceable region 24 of the wall 23 of the supply cavity 22. FIG. 8 shows that the cannula has pierced through the wall 23 into the supply cavity 22. The nonpierceable plate 26 prevents undesired piercing of the region opposite the wall 23, in this case the base plate 38. It is shown that liquid 12 flows out of the pen 28 through the cannula 29 into the supply cavity 22. Due to the restoring force of the spring in the first check valve 31, said valve remains closed, and the liquid does not flow into the metering cavity 20.

[0071] FIG. 8 shows a subsequent step in which the supply cavity 22 is completely filled, and the pen 28 with the cannula 29 has already been pulled out of the wall 23. The wall 23 of the supply cavity 22 is curved slightly upward. As an alternative to the illustration shown here, filling can also occur in such a way that the metering cavity 20 is also filled with the liquid 12. For this purpose, the liquid 12 must exert a pressure in the supply cavity 22 such that the first check valve 31 opens. Preferably, the spring force in the second check valve 32 is then larger, so that an unplanned outflow of the liquid through the second check valve 32 is prevented.

LIST OF REFERENCE SIGNS

[0072] Device 10 [0073] Liquid 12 [0074] Metering apparatus 14 [0075] Inlet 16 [0076] Outlet 18 [0077] Metering cavity 20 [0078] Wall 21 [0079] Supply cavity 22 [0080] Wall 23 [0081] Region 24 [0082] Nonpierceable element 25 [0083] Nonpierceable plate 26 [0084] Pen 28 [0085] Cannula 29 [0086] First check valve 31 [0087] Second check valve 32 [0088] Valve body 33 [0089] Height H [0090] Width B [0091] Length L [0092] Tube connection 34 [0093] Tube 35 [0094] Housing 37 [0095] Floor plate 38 [0096] Finger 40