Liquid dispenser with ventilated bottle and discharge head for this purpose

Abstract

A discharge head for a liquid dispenser having a coupling device fastening to an outlet connector of a liquid store, a liquid inlet, and a discharge opening. The discharge head has a pump device conveying liquid from the liquid inlet to the discharge opening, and a ventilation channel. The discharge head has an end surface by which the liquid store is substantially closed off at the distal end of the outlet connector and which is extended through by the liquid inlet. The end surface and the coupling device are formed as part of a common main component. The end surface has a ventilation aperture which is part of the ventilation channel and through which air flows into the liquid store in an inflow direction. The ventilation aperture has a minimum clear cross section of at most 3.Math.10.sup.−2 mm.sup.2.

Claims

1. A liquid dispenser for dispensing cosmetic or pharmaceutical liquids, comprising: a liquid store filled with a cosmetic or pharmaceutical liquid and having an outlet connector; and a discharge head comprising: a coupling device fastened to the outlet connector of the liquid store; a liquid inlet directed in a direction of the liquid store and having a discharge opening; a pump device for conveying liquid from the liquid inlet to the discharge opening; a ventilation channel connecting external surroundings of the discharge head to an interior of the liquid store; and an end surface by which the liquid store is substantially closed off at a distal end of the outlet connector on a of the discharge head, the liquid inlet extending through the end surface, the end surface and the coupling device being formed in a unipartite fashion as part of a common main component, the end surface having at least one ventilation aperture which is part of the ventilation channel and through which air flows into the liquid store in an inflow direction, the at least one ventilation aperture having a cross-section, a narrowest part of the cross-section having a dimension not exceeding 3.Math.10.sup.−2 mm.sup.2, the dimension of the narrowest part of the cross-section being adapted to a surface tension of the liquid in the liquid store such that a maximum hydrostatic pressure generated by the liquid in the liquid store does not result in liquid passing through the at least one ventilation aperture due to a surface tension of the liquid.

2. The liquid dispenser as claimed in claim 1, wherein the at least one ventilation aperture is formed as an opening which narrows steadily in the inflow direction.

3. The liquid dispenser as claimed in claim 1, wherein the at least one ventilation aperture is formed as an opening which narrows counter to the inflow direction.

4. The liquid dispenser as claimed in claim 1, wherein the at least one ventilation aperture is, at a location of the narrowest part of the cross-section, formed by a cylindrical channel portion having a length corresponding at least to a diameter of the cylindrical channel portion at said location.

5. The liquid dispenser as claimed in claim 1, wherein the at least one ventilation aperture has a truncated-cone-shaped or truncated-pyramid-shaped channel portion, a narrowest point of the channel portion corresponding with the narrowest part of the cross-section of the at least one ventilation aperture.

6. The liquid dispenser as claimed in claim 1, wherein the at least one ventilation aperture comprises a plurality.

7. The liquid dispenser as claimed in claim 1, wherein: the main component comprises an altogether hydrophilic or hydrophobic component comprising a plastic with an additive; or the main component comprises, at the end surface, a hydrophilic or hydrophobic coating on one or both sides of the end surface.

8. The liquid dispenser as claimed in claim 1, wherein the discharge head has a sealing ring configured to circumferentially seal the discharge head with respect to the outlet connector of the liquid store, the sealing ring has an areal extent such that, in relation to a main extent direction of the outlet connector of the liquid store, said sealing ring covers the at least one ventilation aperture, and the sealing ring is spaced apart from an exit side of the at least one ventilation aperture so as to form a narrow slot such that air passes into the liquid store past the sealing ring.

9. The liquid dispenser as claimed in claim 8, wherein a side of the end surface faces toward the liquid store and has a planar abutment surface against which the sealing ring bears, and the side of the end surface has a region, the region being recessed in relation to the planar abutment surface, the at least one ventilation aperture opening into the region.

10. The liquid dispenser as claimed in claim 8, wherein the sealing ring has a planar abutment surface disposed to bear against the end surface, and the sealing ring has, on a side of the sealing ring facing toward the end surface, a region, the region being recessed in relation to the planar abutment surface and the region being arranged such that the at least one ventilation aperture opens into the region of the sealing ring.

11. The liquid dispenser as claimed in claim 1, wherein: the discharge head has an actuating push button which is mounted slidingly on the main component;, or the discharge head has an actuating push button, the actuating push button which, together with the main component, defining an interior space, the pump device including a pump chamber arranged in the interior space.

12. The liquid dispenser as claimed in claim 1, wherein the pump device has a pump chamber formed by an elastic compressible hollow body of open form at an entrance side and at an exit side.

13. The liquid dispenser as claimed in claim 1, wherein: the main component has a pump chamber formed from a hollow body and a pump chamber connector projecting beyond the end surface in an opposite direction from the liquid store, the pump chamber connector being attached to the hollow body; or the coupling device is formed as an internal thread; or the coupling device is designed as a detent device, the main component including at least one elastically deflectable detent edge for detent engagement on the outlet connector of the liquid store; or the discharge head has a wall surrounding the ventilation aperture, the wall having at least one surface-forming edge, portions of the wall converging on one another at the at least one surface-forming edge at an angle of at least 135° , the surface-forming edge being of sharp-edged form with a radius of curvature of <0.1 mm; or a central axis of the at least one ventilation aperture extends parallel to a main extent direction of the outlet connector of the liquid store.

14. The liquid dispenser as claimed in claim 1, wherein the discharge head includes an end wall, the end wall having an end wall portion on which the end surface is disposed, the end wall portion being oriented transversely to an actuation direction of the pump device, and the at least one ventilation aperture of the end surface extends through the end wall portion.

15. The liquid dispenser as claimed in claim 14, wherein the end wall and the coupling device are formed as a unitary, one-piece component.

16. The liquid dispenser as claimed in claim 1, wherein the at least one ventilation aperture has a central axis and the outlet connector of the liquid store is substantially cylindrical, and the central axis is substantially parallel to a central axis of the outlet connector.

17. A liquid dispenser for dispensing cosmetic or pharmaceutical liquids, said dispenser comprising: a liquid store having an interior filled with a cosmetic or pharmaceutical liquid, said liquid store having an outlet connector with an open distal end; and a discharge head fastened to said outlet connector of said liquid store, said discharge head comprising: a coupling device connected to said outlet connector of said liquid store; a liquid inlet disposed adjacent to and in communication with said liquid store; a discharge opening; a pump device configured to convey liquid from said liquid inlet to said discharge opening; a ventilation channel disposed to connect said interior of said liquid store to an external environment of said discharge head; and an end wall disposed adjacent said open distal end of said liquid store, said end wall and said coupling device being formed as a unitary, one-piece component, said end wall including an end wall surface disposed to substantially close off said open distal end of said outlet connector of said liquid store, said liquid inlet extending through said end surface, said end surface defining therein at least one ventilation aperture forming part of said ventilation channel, said at least one ventilation aperture being configured to permit air flow into said liquid store in an inflow direction, said at least one ventilation aperture having a cross-section, a narrowest part of said cross-section having a dimension not exceeding 3.Math.10.sup.−2 mm.sup.2, the dimension being adapted to a surface tension of the liquid in said liquid store such that the surface tension prevents passage of the liquid through said at least one ventilation aperture under a maximum hydrostatic pressure generated by the liquid in the liquid store.

18. The liquid dispenser as claimed in claim 17, wherein said end wall is oriented transversely to a longitudinal direction of said pump device and said at least one ventilation aperture extends through said end wall.

19. The liquid dispenser as claimed in claim 18, wherein said at least one ventilation aperture has a central axis oriented substantially parallel to an actuation direction of said pump device.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further advantages and aspects of the invention will emerge from the claims and from the following description of preferred exemplary embodiments of the invention, which are discussed below on the basis of the figures.

(2) FIG. 1 shows a dispenser according to the invention in an overall illustration.

(3) FIGS. 2 and 2A show a first exemplary embodiment in a sectional illustration of the discharge head with an enlarged detail.

(4) FIG. 3 shows, in a view from the liquid store, the arrangement of ventilation apertures in the end wall of the discharge head.

(5) FIG. 4 illustrates the action of the ventilation apertures in the case of an orientation of the dispenser in an upside-down position.

(6) FIGS. 5 and 5A show a second exemplary embodiment in a sectional illustration of the discharge head with an enlarged detail.

(7) FIGS. 6A to 6H show different variants regarding the shaping of the ventilation apertures.

(8) FIG. 7 illustrates the arrangement and effect of a partially hydrophobic embodiment of the discharge head.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

(9) FIG. 1 shows a liquid dispenser 100 according to the invention, in the present case a liquid dispenser for discharging cosmetic lotions. The liquid dispenser 100 has a liquid store 10 in the form of a bottle, at the upper end of which there is arranged an outlet connector 12 with an external thread that is not illustrated in FIG. 1. The liquid store 10 is screwed into a discharge head 20, which itself has a main component 30 which forms the base of the discharge head 20 and on which an actuating pushbutton 40 is mounted so as to be slidingly displaceable in an actuating direction 4. The outlet connector 12 of the dispenser 100 extends along this same direction 4.

(10) The discharge head 20 has a pump device 50 which is not illustrated in FIG. 1 and by means of which liquid can be conveyed out of the liquid store 10 to a discharge opening 44.

(11) Since the quantity of liquid remaining in the liquid store 10 is hereby reduced, air from a surrounding atmosphere must pass into the liquid store 10 for the purposes of pressure equalization. The problem here lies in the fact that a ventilation channel that leads into the liquid store 10 from external surroundings simultaneously also allows liquid to escape through the ventilation channel in an upside-down position of the liquid dispenser 100, for example if the dispenser is transported in a bag.

(12) The ventilation device described below serves for the purpose of permitting the ventilation without the risk of a relevant quantity of liquid escaping in the upside-down position.

(13) FIG. 2 shows a first exemplary embodiment of a dispenser according to the invention, and of the discharge head thereof, in a sectional view. It can be seen that the pump device 50 is formed by virtue of a bellows-like hollow body 54, which is of open form at its entrance side and its exit side, being fastened to the main component 30 and to the actuating pushbutton 40, wherein said hollow body is, at the main component 30, clamped onto a pump chamber connector 38 which, by means of a stop surface 38A, limits the pushing-on length of the hollow body 54.

(14) At the actuating pushbutton 40, the hollow body 54 is clamped into a sleeve portion 47. That wall of the hollow body 54 which surrounds the pump chamber 52 is of bellows-like form in order to realize a reproducible compression when the actuating pushbutton 40 is pushed down by manual exertion of force on the pressure surface 42. At the entrance side and at the exit side of the pump chamber 52, there are provided an inlet valve 56 and an outlet valve 58, wherein both valves each have an elastic valve portion 56A, 58A which is in each case formed integrally on the hollow body 54, such that, in addition to the main component 30 and the actuating pushbutton 40, only one further component is required in order to provide a reliable pump device.

(15) The main component 30 is that component which provides the coupling device 36, in the present case in the form of an internal thread. Said main component is at the same time that component which forms an end surface 32 on an end wall of the mail component 30, which end surface 32 in the present case is of substantially planar form, though need not be of such form, and which closes off the liquid store 10 in the region of its outlet connector 12. For the purposes of sealing, a sealing ring 26 is provided, which is of functional importance in the context of the invention in the second embodiment described in more detail below. The end surface 32 of the main component 30 is extended through by an opening for two purposes. Firstly, the liquid inlet 34 is provided here, which opens into the pump chamber connector 38 and on which a riser pipe 28 is provided which projects into the liquid store 10.

(16) Furthermore, the end surface 32 is interrupted by a total of eight ventilation apertures 70 which are part of a ventilation channel 60 by means of which, after the discharge of liquid, air can flow into the liquid store 10 for the purposes of the pressure equalization. The ventilation channel 60 or ventilation path is illustrated in its entirety by a dashed line. The ventilation path runs through a gap between the main component 30 and the actuating pushbutton 40 into an interior space formed by said two components, and from there to the ventilation apertures 70.

(17) Here, as will be discussed in more detail below, the ventilation apertures 70 are of such slim form that, although air can flow in, no liquid flows out under normal conditions.

(18) As illustrated on the basis of FIG. 3, a total of eight ventilation apertures 70 is provided, because, owing to the very slim form of the ventilation apertures 70, one on its own would not be sufficient to compensate the loss of liquid in the liquid store 10 as a result of multiple successive actuations. Here, the eight ventilation apertures 70 are arranged uniformly with spacings of 45° with respect to one another so as to surround the pump chamber connector 38 and the central axis thereof, resulting in a large spacing between the ventilation apertures 70. The spacing between mutually opposite ventilation apertures 70 amounts to approximately 25 mm, and the spacing between adjacent ventilation apertures 70 amounts to approximately 8 mm. This serves the purpose that, in the event of an undesired passage of liquid through one of the ventilation apertures 70, the liquid should as far as possible not run, on that side of the end surface 32 which is averted from the liquid store 10, into the region of another ventilation aperture, so as not to disrupt the function thereof.

(19) FIG. 4 shows a detail of the discharge head 20 of FIG. 1 in an upside-down position of the dispenser 100. It can be seen that the liquid, indicated by means of bubbles, flows as far as the ventilation aperture 70 and, at the channel portion 74 thereof with minimum clear cross section and with a sharp-angled surface-forming edge 78 of approximately 60°, a domed surface 90 illustrated by dashed lines forms which, owing to the surface tension of the liquid, prevents the ingress of further liquid into the ventilation aperture 70. Even if liquid passes into the ventilation aperture 70, it is in turn the case, at the opposite side of the ventilation aperture 70, that a situation arises in which a domed surface forms which is stable under the action of the surface tension of the liquid and which prevents the passage of further liquid in an effective manner.

(20) FIGS. 5 and 5A show a somewhat different design. Here, the sealing ring 26 is provided with a smaller inner diameter, and additionally with a depression 26B on its top side, such that, here, the top side of the sealing ring 26 is recessed somewhat in relation to an abutment surface 26A of the sealing ring 26 which is disposed against the end surface 32. Together with the end surface 32, a very narrow slot 68 is hereby formed, which however does not impede the entry of air into the liquid store 10.

(21) By means of this design, it is ensured that the ventilation apertures 70 are not, as a result of jerky movements of the liquid dispenser 100 or even a shaking action, acted on by liquid impinging directly on the ventilation aperture 70, which would be capable of passing through the ventilation aperture 70.

(22) FIGS. 6A to 6H show different possible embodiments of the ventilation apertures 70.

(23) In the case of FIGS. 6A and 6B, the ventilation apertures 70 are in each case of truncated-cone-shaped or truncated-pyramid-shaped form, wherein, in the case of the embodiment of FIG. 6A, said ventilation apertures narrow toward the liquid store 10 and, in the case of the embodiment of FIG. 6B, said ventilation apertures narrow in the opposite direction. Such ventilation apertures 70 are particularly easy to produce because mold portions of an injection mold for forming such ventilation apertures 70 are required only on one of the two mold parts for producing the main component 30. On the opposite side, the tool can be of planar form in the same region. It has been found that the liquid pressure required to pass through a ventilation aperture shaped in this way is scarcely lower than in the case of a purely cylindrical aperture as in FIG. 6D.

(24) In the design as per FIG. 6C, the ventilation apertures 70 narrow proceeding from both sides. This yields three surface-forming edges 78 of approximately 135′, approximately 90° and approximately 135° one behind the other, which are each suitable for preventing the escape of liquid.

(25) In the design of FIG. 6E, an encircling trench-like depression 77 is provided on the end surface 32, into which depression the ventilation apertures 70 open. The ventilation apertures 70 can thus be shorter, which makes the production process easier. In the case of the embodiment of FIG. 6F, such depressions 77 are provided to both sides of the end surface 32.

(26) The design of FIG. 6G differs from the similar design of FIG. 6A in that the sealing ring 26 does not have a depression. Instead, a depression 32D is provided on the underside of the end surface 32, which depression likewise makes it possible to use a sealing ring 26 with an inner diameter which covers the ventilation apertures 70 and which therefore does not allow a direct impingement of the liquid on the ventilation aperture 70 in the event of the dispenser 100 being shaken.

(27) The design of FIG. 6H is one with relatively complex shaping of the ventilation aperture. The ventilation aperture 70 illustrated here has, at both sides, a conical shaping, wherein a short cylindrical sub-portion defines the point that is narrowed to the greatest degree.

(28) In the design as per FIG. 7, the main component 30 and the end surface 32 are of hydrophobic design, but provided with a hydrophilic coating 79 on the bottom side thereof. This combination has the effect that, firstly, in the upside-down position, a liquid surface 94 which prevents the further passage of liquid forms in a particularly reliable manner at the boundary between the hydrophilic and the hydrophobic region. Additionally, liquid that has entered the ventilation apertures 70 during a brief period in the upside-down position is drawn from the hydrophobic ventilation aperture 70 back into the liquid store 10 by the hydrophilic coating 79 after a return into the initial position.