DE20100428U1 - Dispenser for fluids - Google Patents

Description

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10 January 2001

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Steven Padar
Theresenstrasse 17

D-65779 Kelkheim

Fluid dispensing device

Fluid dispensing device

The present invention relates to a dispensing device for fluids according to the preamble of patent claim 1.

Conventional dispensing devices for pharmaceuticals or cosmetics are well known. Such dosing pumps allow a specific amount of a fluid to be pumped out of a storage container.

EP-O 739 247 Bl describes a suction-pressure pump for fluid containers, which is intended for spraying liquids whose service life is reduced when they come into contact with atmospheric oxygen. The known metering pump has a pressure cylinder which projects into the fluid container and in which a piston is guided in a sealing manner. A pressure chamber is formed in the pressure cylinder, which is delimited by the piston and by a ball valve acting opposite the fluid container, which closes when there is excess pressure and opens when there is negative pressure, and which is connected to an axial pump channel. The piston is held in the upper rest position by spring force. A second valve is arranged within the pump channel, which opens when there is excess pressure in the pressure chamber and closes when there is negative pressure in the pressure chamber. A gap is provided between the second valve and the distal end of the pump channel. When the piston is pushed down, the pressure in the pressure chamber increases, the valve to the fluid container closes and the liquid in the pressure chamber escapes under pressure through the axial pump channel past the opened second valve into the intermediate space and from there to the outside. When the piston is released, a negative pressure is created in the pressure chamber, so that the second valve closes again and the ball valve

to the fluid container opens and liquid is sucked into the pressure chamber. ....... ........ .: .··..··. : .··..··. : i .:

A major disadvantage of the known suction-pressure pump is that the liquid delivered does not reach the area to be treated, such as the eye or nose of a patient, completely germ-free.

The object of the present invention is therefore to provide a dispensing device for fluids from a storage container, which ensures sterile storage of the liquid or the dispensing of sterile liquid.

This object is achieved by means of the features specified in claim 1. Advantageous embodiments of the invention are the subject of the subclaims.

The inventive dispensing device for fluids from a storage container has a housing body which can be placed on the storage container and in which a pressure chamber is formed. The pressure chamber is limited at the top by a piston guided in the pressure chamber and at the bottom by a first valve acting opposite the storage container. The first valve closes when there is excess pressure in the pressure chamber, whereas it opens when there is negative pressure in the pressure chamber. Furthermore, a pump channel is provided in the housing body, which is connected on the one hand to the pressure chamber and on the other hand to the environment. A second valve is provided in the pump channel, which opens when there is excess pressure in the pressure chamber and closes when there is negative pressure. The second valve is designed in such a way that the pump channel can be closed at the distal end of the housing body.

In contrast to the prior art, there is no gap between the second valve and the end of the pump channel in which liquid could collect after spraying, which would be exposed to the environment and thus contaminated with germs after a certain period of time, especially if it is a nasal spray in which the distal end of the housing body is in

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the patient's nose. This prevents a germ-laden liquid residue from being released together with the subsequent liquid when spraying again. This is prevented by the design of the second valve, as the liquid within the pump channel is completely separated from the environment by the second valve.

In a preferred embodiment of the dispensing device according to the invention, the second valve comprises a stationary sealing body around which flow can flow and an elastic sealing disk. The stationary sealing body extends into a recess in the sealing disk, which seals against the stationary sealing body. The stationary sealing body is understood to be an essentially rigid body attached to the housing body and of any shape. The sealing disk, on the other hand, is deformable due to its elasticity. When pressure is generated within the pressure chamber, the liquid flows around the sealing body and presses against the sealing disk, so that it is raised in the area where it rests against the sealing body and liquid can escape. This embodiment provides a valve that is particularly easy to manufacture. In addition, this embodiment supports the formation of drops at the distal end of the housing body when the liquid is dispensed.

In a further preferred embodiment of the dispensing device according to the invention, the sealing disk rests linearly on the stationary sealing body. The sharp demarcation of the pump channel from the environment by means of a linear system ensures a high level of tightness of the second valve, which is not achieved to the same extent with a flat system, since in the latter case a significantly higher manufacturing precision of the parts that are adjacent to one another would be required, which cannot always be achieved.

In order to achieve a particularly even distribution of the escaping liquid, the sealing disc is located in a particularly preferred

Embodiment of the dispensing device in a circular manner on the stationary sealing body. This is achieved by a rotationally symmetrical stationary sealing body and a circular recess in the sealing disk.

In order to ensure easier flow around the stationary sealing body, according to a preferred embodiment of the invention the pump channel has a larger diameter in the region of the stationary sealing body than in a region facing the pressure chamber.

In a particularly preferred embodiment of the dispensing device according to the invention, the sealing disk is pre-tensioned against the stationary sealing body. The pre-tensioning means that the stationary sealing body and the elastic sealing disk are arranged in relation to one another in such a way that the edge of the recess in the sealing disk is pressed outwards. By pre-tensioning the elastic sealing disk, a higher tightness of the second valve can be achieved.

In an advantageous embodiment of the invention, the stationary sealing body is essentially conical on the side facing the sealing disk. The tip of the cone protruding into the recess of the sealing disk brings the escaping liquid together, so that random splashing to the sides is prevented and drop formation is supported during dispensing.

The aforementioned advantage is also achieved, although not to the same extent, by a further preferred embodiment in which the stationary sealing body is essentially spherical cap-shaped on the side facing the sealing disk.

In a further preferred embodiment of the dispensing device, the second valve has a displaceable sealing body. This is resiliently mounted against

the distal end of the pump channel is pre-tensioned. The spring pre-tension can be achieved by a tension or compression spring or a spring element such as an elastic band.

In order to avoid in any case an arrangement of the spring element on the outlet side and thus a risk of accumulation of liquid on it, the spring element is preferably arranged on the side of the sealing body facing the pump channel.

In the following, the invention is explained in more detail using embodiments with reference to the accompanying figures.

Show it:

Fig. 1 the dispensing device according to the invention together with the

Storage container in section view, with the piston in the rest position,

Fig. 2 is a section along the line ΛΛ-Π of Fig. 1,

Fig. 3 shows section A of Fig. 1 in an enlarged view,

Fig. 4 shows section B of Fig. 1 with the second valve in a first

embodiment,

Fig. 5 the second valve of Fig. 4 in the open position,

Fig. 6 shows section B of Fig. 1 with the second valve in a second

embodiment,
Fig. 7 shows section B of Fig. 1 with the second valve in a third

embodiment,
Fig. 8 shows section B of Fig. 1 with the second valve in a fourth

Design and
Fig. 9 shows section B of Fig. 1 with the second valve in a fifth

embodiment.

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First, the basic structure of the dispensing device will be explained using Fig. 1 to 3.

The dispensing device is intended for spraying a liquid from a storage container 1, wherein in the present embodiment a collapsible bag 1a is provided which is inserted into the storage container 1.

The housing body 2 of the dispensing device consists of a lower housing part 3 and an upper housing part 4, which is placed on the lower housing part 3. The lower housing part 3 of the housing body is designed as a closure cap, which is placed on the storage container 1 in a snap-in and sealing manner. The lower housing part 3 accommodates a pressure cylinder 5, which extends into the storage container 1. A pressure chamber 6 is formed at the lower end of the pressure cylinder 5, which is delimited at the upper end by a piston 7 guided in the pressure cylinder and at the lower end by a first valve 8 acting opposite the storage container 1.

The piston 7 has a lower section 7a and an upper section 7b, the outer diameter of the lower section being slightly larger than the diameter of the upper section. The pressure cylinder 5 accordingly has a lower section 5a with a larger inner diameter and an upper section 5b with a smaller diameter. In the rest position shown in Fig. 1, the lower section 7a of the piston 7 is prestressed against the upper section 5b of the pressure cylinder 5 by means of a compression spring 9 inserted into the pressure cylinder 5. The upper section 5b of the pressure cylinder 5 has an annular projection 26 with several grooves 27 distributed around the circumference on its upper edge. The inner diameter of the annular projection 26 corresponds to the outer diameter of the piston 7, so that the piston is guided in the projection (Fig. 2). Since the piston 7 otherwise has a smaller diameter than the pressure cylinder 5, a narrow gap 10 remains between the outer wall of the piston and the inner wall of the cylinder.

The sealing of the piston 7 with respect to the pressure cylinder 5 is achieved solely by means of a sealing lip 11 which is arranged at the lower end of the piston. In the lower region of the pressure chamber 6, the inner diameter of the pressure cylinder 5 increases slightly, only to then decrease again. In the region of this extension 13, the sealing effect of the lip 11 is lost (Fig. 3).

The gap 10 between the upper section 7b of the piston and the upper section 5b of the pressure cylinder 5 is closed by a flexible seal 19. The seal 19 is made of polyethylene and has a circular hole 20 in the center in which the piston 7 is guided in a sealing manner. The outer edge of the seal 19 is inserted in a sealing manner into the lower housing part 3 of the housing body 2, with the seal resting with its underside on a circumferential shoulder 21 of the housing body in the area of the outer edge, but being freely movable in the inner area.

Above the pressure chamber 6, the pressure cylinder 5 is provided with several slots 12 distributed around the circumference. The piston 7 has a first axial channel 14 which is connected to a riser pipe 15 which is fastened to the upper housing part 4 and in which a second axial channel 16 extends. The second axial pumping channel in turn reaches as far as a third axial channel 17 which is arranged within the upper housing part 4 and extends as far as the distal end 18 of the housing body 2 or the upper housing part 4. The liquid can thus escape from the pressure chamber 6 to the environment via the first, second and third channels 14, 16, 17 which, arranged one behind the other, form the pumping channel 23. The pumping channel 23 is closed at the distal end 18 of the housing body 2 by means of a second valve 25 formed in the third channel 17.

The upper and lower housing parts 3, 4 of the housing body 2 each have a cylindrical section 3a, 4a, which can be moved relative to one another. An opening 24 for sucking the residual air out of the collapsible bag 1a is provided on the upper housing part 4 next to the riser pipe 15.

This residual air can be extracted using a suction device (not shown), although the method for extracting the residual air will not be discussed in detail here. When extracted, the residual air flows through the slots 12 in the pressure cylinder 5 and the gap 10 between the upper section 5b of the pressure cylinder 5 and the upper section 7b of the piston 7 as well as the grooves 27 on the upper edge of the pressure cylinder into the space 22, since the sealing effect of the seal 19 is lost.

The dispensing device works as follows. First, it is assumed that the storage container 1 is filled with liquid, but the dispensing device is still free of liquid. When the upper and lower housing parts 3, 4 of the housing body 2 are pressed together, the piston 7 moves into the pressure chamber 6; the air in the pressure chamber is released to the environment via the first, second and third channels 14, 16, 17, which form the pump channel 23, and the opened second valve 25. The second valve 25 is open due to the excess pressure in the pressure chamber 6, whereas the first valve 8 is closed. When the piston 7 springs back due to the spring force, a negative pressure is created in the pressure chamber 6, so that the second valve 8 opens, whereas the first valve 25 closes. As a result of the negative pressure, liquid is sucked from the storage container 1 into the pressure chamber 6. If the piston is then pushed forward again, the liquid is pressed outward from the pressure chamber 6 via the pump channel 23, whereby the second valve 25 opens and the first valve 8 closes.

Since the second valve 25 closes the pump channel 23 at the distal end 18 of the housing body 2 after each pumping process, no germs can enter the pump channel 23. There is no risk of residual liquid accumulating at the distal end 18 due to a cavity or similar hollow space.

With reference to Figs. 4 to 9, different embodiments of the second valve and their arrangement within the third channel 17 are described below.

Fig. 4 shows the second valve 25 in a first embodiment. The pump channel 23 formed by the first, second and third channels 14, 16, 17 extends to the distal end 18 of the housing body 2. A section 28 of the pump channel 23 adjacent to the distal end 18 has a larger diameter than a section facing away from the distal end 18, so that a projecting projection 29 facing the distal end 18 is formed within the pump channel 23.

A stationary sealing body 30 is arranged within the section 28, which is supported on the projecting projection 29 via four symmetrically arranged supports 31. Although the supports 31 and the stationary sealing body in Fig. 4 have a different hatching than the housing body 2, they can nevertheless be formed as one piece. The stationary sealing body 30 is conical, the axis of the cone being arranged on the longitudinal axis of the pump channel 23 and the tip of the cone pointing in the direction of the distal end 18 so that it protrudes from the pump channel 23. The pump channel 23 is closed at the distal end 18 by means of a round elastic sealing disk 32 which has a central circular recess 33. The stationary sealing body 30 and the sealing disk 32 are arranged in such a way that the tip of the conical stationary sealing body 30 extends through the recess 33, whereby the sealing disk 32 or the edge of the recess 33 lies sealingly against the stationary sealing body 30 or the conical surface of the conical stationary sealing body 30. The sealing disk 32 lies in a circular line against the stationary sealing body 30, whereby in Fig. 4 a section through this circular line is identified with the reference number 34.

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Fig. 5 shows the functioning of the second valve in the first embodiment. It is assumed that liquid (not shown) is already present in the pump channel 23 (Fig. 4). If the pressure within the pressure chamber 6 (Fig. 1) and thus within the pump channel 23 is increased, the edge of the elastic sealing disk 32 resting on the stationary sealing body 30 is pressed outwards so that a connection is created between the pump channel 23 and the environment. As shown by the arrows in Fig. 5, the liquid is pressed upwards through the pump channel 23. In the section 28 of the pump channel 23, the liquid flows radially outwards through the spaces between the supports 31 in order to flow around the stationary sealing body 30. The liquid then exits at the distal end 18.

As can be seen from Fig. 5, the first embodiment, as well as the second and third embodiments described with reference to Figs. 6 and 7, are suitable for forming a drop 35 of the liquid at the distal end 18, which is shown in dashed lines in Fig. 5. Thus, the embodiments mentioned are particularly suitable for a dispenser for eye drops or the like.

Fig. 6 shows the second valve 25' in a second embodiment. The second embodiment is similar to the first embodiment, so that in Fig. 6 the same reference numerals are used for the same parts and only the differences are discussed. In contrast to the first embodiment, the section 28 of the pump channel 23 adjacent to the distal end 18 is shorter in the second embodiment. In this way, the stationary sealing body 30 protrudes so far into the recess 33 that the edge of the recess 33 is pressed outwards. In this way, the elastic sealing disk 32 is prestressed against the stationary sealing body 30. In order to get from the first to the second embodiment, however, the section 28 does not necessarily have to be shortened. Rather, it is also possible to shorten the length of the supports 31 and/or the length of the sealing body 30 and/or the

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Size of the recess 33. Although the edge of the recess 33 is pressed outwards, care should be taken to ensure that the sealing disk 32, as in the first embodiment, rests linearly against the stationary sealing body 30, as is indicated in Fig. 6 by the reference numeral 34. Regarding the functioning of the second valve 25' in the second embodiment, reference is made to the description given with reference to Fig. 5.

The pre-tension increases the sealing effect of the second valve 25' in the second embodiment. In addition, a higher pressure is required in the pressure chamber 6 to open the second valve 25'.

Fig. 7 shows a third embodiment of the second valve 25", the third embodiment essentially corresponding to the first embodiment, so that the same reference numerals have been used for the same parts. In contrast to the first embodiment, the stationary sealing body 35 in the third embodiment is designed in the shape of a spherical cap. Like the conical stationary sealing body 33 of the first embodiment, the stationary sealing body 35 is suitable for generating a drop (not shown) at the distal end 18. The mode of operation is analogous to that of the first embodiment.

A fourth and fifth embodiment of the second valve 25'" and 25"" are shown in Figs. 8 and 9, respectively. Both embodiments have in common that the pump channel 23 is narrower in a section adjacent to the distal end 18 than in a section facing away from the distal end 18, so that a projecting projection 37 pointing away from the distal end 18 is formed in the pump channel 23.

In the fourth embodiment (Fig. 8), the pump channel 23 is closed at the distal end 18 by a conical, movable sealing body 38, the axis of which lies on the axis of the pump channel 23, the tip of the

conical, movable sealing body 38 projects into the pump channel 23. The tip is followed by an elongated connecting element 39, which in turn is connected to a support element 40, which is supported on the projecting projection 37 in the pump channel 23. Holes 41 for the passage of the liquid are provided in the support element 40. The movable sealing body 38 and the connecting element 39 are formed as one piece and are elastically deformable. If the pressure in the pump channel 23, which acts on the movable sealing body 38, increases, the connecting element 39 lengthens elastically and the sealing body 38 lifts off the distal end 18, so that liquid can escape.

The fifth embodiment is similar to the fourth embodiment, but the movable sealing body 42 is spherical. An elongated connecting element 43 is also connected to the movable sealing body 42, but neither the movable sealing body 42 nor the connecting element 43 are elastic. The support element 40 corresponds to the support element of Fig. 8. In order to ensure the displaceability of the sealing body 42, a compression spring 44 is arranged between the support element 40 and the projecting extension 37, which presses the support element 40, the connecting element 43 and thus the movable sealing body 42 downwards and against the distal end 18. When the pressure in the pump channel 23 increases, the movable sealing body 42 is displaced upwards against the spring force of the compression spring 44 and releases the pump channel 23 so that liquid can escape.

In contrast to the previously described embodiments, the fourth and fifth embodiments do not tend to form drops as much, so that their field of application lies rather in dispensing devices for spraying the liquid, as is the case with a nasal spray, for example.

Claims (10)

1. Dispensing device for fluids from a storage container, with a housing body ( 2 ) which can be placed on the storage container ( 1 ) and in which a pressure chamber ( 6 ) is formed which is limited at the top by a piston ( 7) guided in the pressure chamber (6 ) and at the bottom by a first valve ( 8 ) acting opposite the storage container ( 1 ), which closes when there is excess pressure in the pressure chamber ( 6 ) and opens when there is negative pressure, wherein a pump channel ( 23 ) is also provided which is connected on the one hand to the pressure chamber ( 6 ) and on the other hand to the environment and in which a second valve ( 25 , 25 ', 25 ", 25 ''', 25 "") is provided which opens when there is excess pressure in the pressure chamber ( 6 ) and closes when there is negative pressure, characterized in that the second valve ( 25 , 25 ', 25 ", 25 ''', 25 "") is designed such that the pump channel ( 23 ) can be closed at the distal end ( 18 ) of the housing body ( 2 ). 2. Dispensing device according to claim 1, characterized in that the second valve ( 25 , 25 ', 25 ") comprises a stationary sealing body ( 30 , 35 ) around which fluid can flow and an elastic sealing disk ( 32 ), the stationary sealing body ( 30 , 35 ) extending into a recess ( 33 ) in the sealing disk ( 32 ), which sealingly abuts the stationary sealing body ( 30 , 35 ). 3. Dispensing device according to claim 2, characterized in that the sealing disc ( 32 ) rests linearly on the stationary sealing body ( 30 , 35 ). 4. Dispensing device according to claim 3, characterized in that the sealing disc ( 32 ) rests in a circular manner on the stationary sealing body ( 30 , 35 ). 5. Dispensing device according to one of claims 2 to 4, characterized in that the pump channel ( 23 ) has a larger diameter in the region of the stationary sealing body ( 30 , 35 ). 6. Dispensing device according to one of claims 2 to 5, characterized in that the sealing disc ( 32 ) is prestressed against the stationary sealing body ( 30 ). 7. Dispensing device according to one of claims 2 to 6, characterized in that the stationary sealing body ( 30 ) is substantially conical on the side facing the sealing disk ( 32 ). 8. Dispensing device according to one of claims 2 to 6, characterized in that the stationary sealing body ( 35 ) is essentially spherical cap-shaped on the side facing the sealing disk ( 32 ). 9. Dispensing device according to claim 1, characterized in that the second valve ( 25 ''', 25 "") has a displaceable sealing body ( 38 , 42 ) which is resiliently prestressed against the distal end of the pump channel ( 23 ). 10. Dispensing device according to claim 9, characterized in that a spring element ( 39 , 44 ) is provided for prestressing the sealing body ( 38 , 42 ), wherein the spring element ( 39 , 44 ) is arranged on the side of the sealing body ( 38 , 42 ) facing the pump channel ( 23 ).