EP3736049B1 - Discharge head and liquid dispenser with a discharge head - Google Patents

Description

FIELD OF APPLICATION AND PRIOR ART

The invention relates to a discharge head for a liquid dispenser for dispensing pharmaceutical or cosmetic liquids and a liquid dispenser which is provided with such a discharge head.

Generic discharge heads have a deformable pumping chamber component, which is arranged between a base and an actuating button, so that its internal volume in cooperation with an inlet valve and an outlet valve forms a pumping chamber, the contents of which can be discharged by depressing the actuating button. In a particularly simple configuration, generic discharge heads can consist of only three components, since the inlet valve and the outlet valve and any ventilation valve that may be present can be formed by valve lips or valve bodies provided integrally on the pump chamber component together with a counter-wall of the base or the actuating pusher.

From the EP 3427840 A1 a generic dispenser is known which has an inlet valve, an outlet valve and a ventilation valve. However, the design presented there is still in need of improvement with regard to the ventilation of the pump chamber and in particular the ventilation of a liquid reservoir coupled to the discharge head. It was found that the ventilation valve is difficult to tune in such a way that it reliably opens at all times in the event of negative pressure, but otherwise closes reliably. If the vent valve does not close when the pressure is equalized, there is a risk of the dispenser leaking through the vent valve. EP0394750A2 discloses a prior art bellows metering pump.

TASK AND SOLUTION

The object of the invention is to further develop a generic discharge head in such a way that it shows advantageous behavior when venting the pump chamber during commissioning and for venting the liquid reservoir when in use.

According to a first aspect not according to the invention, a discharge head is proposed which has a base and an actuating pusher which can be depressed relative to the base between an unactuated end position and an actuated end position in an actuating direction. Furthermore, the proposed discharge head has a liquid inlet for connection to a liquid reservoir and a discharge opening for dispensing liquid in an environment. A pumping device is provided for conveying liquid from the liquid reservoir to the discharge opening. This pumping device has a deformable pumping chamber component which is open on both sides and which is fixed to the base and the actuating pusher and surrounds a variable-volume pumping chamber which has an inlet valve in the direction of the liquid reservoir and an outlet valve in the direction of the discharge opening.

The discharge head also has at least one ventilation opening that penetrates the base and is associated with a ventilation valve. The ventilation opening and the ventilation valve allow air to flow into the liquid reservoir in order to allow pressure equalization after liquid has been removed. At the base, the aeration valve has a circumferential annular web which rises above a surrounding, radially extending top wall of the base and the inside of which forms a circumferential valve surface for a valve tip to rest on.

Said circumferential valve surface is provided on the base, which is inherently or by being coupled to a fluid reservoir placed in a state of stress which can act on the valve surface and permit the reproducibility of the shaping of the valve surface.

In order to ensure that the ventilation valve opens in the desired manner when the pressure in the liquid reservoir is negative and is otherwise closed, two measures are proposed which are preferably implemented in combination.

On the one hand, it is proposed to provide a reinforcement structure, preferably in the form of a circumferential reinforcement web, on the top wall surrounding the annular web on the outside of the annular web. In the area of this reinforcing web, the top wall is preferably at least 50% thicker than in the opposite inner and outer area of the top wall.

The reinforcement structure is preferably arranged opposite an area of an underside of the cover wall, on which a storage connector is connected after the liquid storage device has been coupled or bottleneck of the liquid reservoir. The reinforcement structure is preferably arranged at least partially opposite a clear cross section of the storage nozzle or bottle neck. The reinforcement structure can thus at least partially absorb a stress coupled into the base from the accumulator neck or bottleneck and thus only allow it to reach the annular web and the valve lip there to a small extent or not at all.

The second measure, which is preferably provided together with the mentioned reinforcement structure, is that the peripheral annular web is part of a sleeve-shaped structure which forms the peripheral annular web above the top wall and which extends flush with the adjacent top wall and below its planes and there forms a circumferential wall section aligned with the ring web.

On the inside, the cover wall thus merges into a sleeve shape, which forms the annular web with the valve surface above the level of the cover wall and forms the circumferential wall section below the cover wall. This preferably transitions into a peripheral ring-shaped wall which is pierced by at least one ventilation opening. The peripheral wall section can in particular also facilitate the coupling to the liquid reservoir and can serve as a guide. When the discharge head is attached to the liquid reservoir, the wall section preferably protrudes into the bottle neck or storage nozzle of the liquid reservoir.

It has been found that the sleeve-like structure mentioned brings about a significant stabilization of the position of the valve surface. In particular, together with the mentioned reinforcement structure, it is achieved that even a very strong state of stress in the outer area of the base, for example due to screwing on the discharge head too tightly, does not negatively affect the opening properties of the ventilation valve.

According to a second aspect not according to the invention, a discharge head is proposed, in particular a discharge head of the type described above with an improved ventilation valve, which also has the elements mentioned of the base and the depressible actuating pusher as well as the liquid inlet, the discharge opening and the pump chamber component open on both sides with an inlet valve and outlet valve having formed pumping device.

As also described for the first aspect, the discharge head has at least one ventilation opening which penetrates the base and to which a ventilation valve is assigned. This ventilation valve has a circumferential ring ridge at the base, the inside of which forms a valve surface. It also has a valve lip, which is formed in one piece with the pump chamber component and which, when the ventilation valve is closed, bears circumferentially on the valve surface.

In order to fasten the pump chamber component to the base, the latter has an inlet connector forming the liquid inlet, onto which a fastening section of the pump chamber component is pushed. For its part, this inlet connection has a support structure with at least one outward-facing and non-circumferential support surface, which comes into contact with the pump chamber component at least towards the end of the depression of the actuating pusher and thereby causes a contact pressure force with which the valve lip bears against the valve surface to be circumferential is not uniform.

The inlet connection is the carrier of the pump chamber component and thus also of the valve lip of the ventilation valve provided thereon. The support structure provided on the outside of the inlet connection ensures that a negative pressure in the liquid reservoir does not result in a uniform force being applied to the valve lip all around. It has been shown that such a uniform application of force on the one hand makes opening itself more difficult and more difficult to calculate, especially if the valve lip has an expanding shape, with a straight line between a contact surface at the distal end of the valve lip and the root of the valve lip on the pump chamber component being one with the direction of actuation Includes angles between 30 ° and 60 ° and thus has a high inherent rigidity. On the other hand, the all-round uniformity of the application of force can cause the sealing lip to flutter and thus generate unwanted noise.

The non-uniformity introduced by the support structure prevents this since it results in an area of the valve lip with an increased tendency to open. A reproducible opening without noise is hereby achievable.

Although it is possible in principle to have the support structure reduce the opening tendency only in a limited peripheral area, it is considered advantageous if the support structure has a plurality of support surfaces, preferably between 2 and 12, in particular between 4 and 8, which are uniform over the circumference are distributed. Between these supporting surfaces are the areas with an increased tendency to open.

In particular, the support structure can have a rib or a plurality of ribs whose end faces pointing in the direction of the actuating pusher form the support faces. At the same time, these ribs can bring about a partial stiffening of the base, which counteracts the initially mentioned deformation of the valve surface of the ventilation valve. The at least one ventilation opening can preferably be arranged circumferentially between these ribs.

According to a third aspect, not according to the invention, a discharge head is proposed, in particular a discharge head of the type described above with an improved ventilation valve, which in turn has the elements mentioned of the base and the depressible actuating pusher as well as the liquid inlet, the discharge opening and the pump chamber component open on both sides with a deformable inlet valve and outlet valve having formed pumping device.

Said outlet valve has a circumferential annular web which protrudes from an inner end wall of the actuating pusher in the direction of the base and whose outer side forms a circumferential valve surface. On the inside of this, the discharge head has an additional displacement structure protruding from the inside end face of the actuating pusher, this displacement structure having a receiving space open in the direction of the pump chamber, which is laterally closed by a surrounding wall. The displacement structure is separated from the ring web, preferably by a peripheral recess.

The displacement structure reduces the pumping chamber volume, with the use of a bellows as the main shape of the pumping chamber component in particular, this reduction does not affect the usable pumping chamber volume, i.e. the amount of liquid that can be discharged with one actuating stroke, but only the unusable residual volume of the pumping chamber. In addition to the direct reduction in the volume of the pumping chamber, the displacement structure provides an area for accommodating residual air through the accommodating space it forms. The air, which is difficult to expel, collects in this in the pump chamber, which ensures that it does not reach the outlet valve or only to a small extent and interferes with its function.

The surrounding wall of the displacement structure preferably extends beyond the ring web into the pump chamber. While the ring web itself can only have a limited extent in the direction of the base due to the shape of the pump chamber component, in particular in its configuration as a bellows, the displacement structure can extend further into the pump chamber in the actuation direction.

The pump chamber has a maximum volume V _PMax , which is defined by the interior of the pump chamber between the inlet valve and the outlet valve when the actuating pushbutton is in the unactuated end position. The receiving space has a receiving space volume VA, which is formed by that partial volume of the pump chamber which is enclosed within the surrounding wall. The ratio between the receiving space volume VA and the pump chamber volume V _PMax is preferably between 1:50 and 1:10.

According to the invention, a discharge head is proposed, in particular a discharge head of the type described above with an improved ventilation valve, which also has the elements mentioned of the base and the depressible actuating pusher as well as the liquid inlet, the discharge opening and the pumping device formed by a deformable pump chamber component open on both sides with inlet valve and outlet valve. It is provided that the discharge head has at least one ventilation opening which penetrates the base and which is assigned a ventilation valve which has a peripheral valve lip which is integrally formed on the deformable pump chamber component and which is prestressed outwards on a peripheral valve bridge of the base applied.

To protect the valve lip from being installed in the discharge head, a protective lip is provided, which is also formed in one piece on the deformable pump chamber component and is arranged on the outside of the valve lip in order to protect the valve lip. The protective lip projects beyond the valve lip, preferably both radially and axially.

The purpose of the protective lip is in particular to protect the valve lip of the ventilation valve during the action prior to assembly as bulk material. In particular, when the valve lip is shaped as a conical valve lip with a shape that widens towards the contact surface, the valve lip is particularly at risk. It has been shown that damage that is sometimes barely visible due to direct injury and relaxation in the deformed state can have a clearly unexpected effect on the reproducibility of the behavior of the valve lip when using the discharge head.

The protective lip protrudes radially and axially beyond the valve lip, so that the protective lip does not come into contact with a substrate either in the horizontal position or in the upright position. The valve lip is preferably set back in relation to the protective lip in such a way that a pump chamber component of the same construction cannot or hardly come into contact with the valve lip.

According to a fifth aspect, not according to the invention, a discharge head is proposed which, in accordance with the configurations described, has the named elements of the base and the depressible actuating pusher as well as the liquid inlet, the discharge opening and the pumping device formed by a deformable pump chamber component open on both sides with inlet valve and outlet valve.

The discharge head has at least one ventilation opening that penetrates the base and is associated with a ventilation valve. This has an encircling valve lip, which is formed in one piece on the deformable pump chamber component and which, prestressed outwards, bears against an encircling valve bridge of the base. A tilting leg which protrudes radially beyond the circumferential valve lip and is integrally formed on the pump chamber component is provided. Correspondingly, a button pointing in the direction of the tilting leg is provided on the actuating pushbutton, which in the actuated end position applies force to the tilting leg and thereby lifts the valve lip of the ventilation valve from the valve bridge or facilitates a pressure-related lifting of the valve lip from the valve bridge.

With such a design, ventilation can be forced when the actuating button is depressed or at least promoted in such a way that even a slight negative pressure in the bottle is sufficient to open the ventilation valve. Said tilting leg, which is preferably designed as a circumferential tilting collar, is connected in one piece to the pump chamber component. It is provided on the pump chamber component in such a way that the sealing lip, which is also connected in one piece to the pump chamber component, is subjected to a force when the tilting leg is pressed down by the actuating pusher.

Said forced opening or simplified opening allows the ventilation valve to be designed in such a way that it is only forced open in this way or only opens when there is a considerable negative pressure in the bottle. A particularly leak-proof ventilation valve can therefore be created. Since the forced opening takes place when the actuating lever is pressed, i.e. before the return stroke and the suction of liquid in the pump chamber that takes place, a slight negative pressure can develop in the liquid reservoir after the return stroke, but this is at least briefly equalized at the latest with the next actuation.

The invention also includes a liquid dispenser for dispensing pharmaceutical or cosmetic liquids, which has a liquid reservoir and a dispensing head for conveying liquid from the liquid reservoir into an environment. The discharge head is designed according to one of the preceding claims.

The liquid reservoir is preferably an aerated liquid reservoir formed by rigid walls, which is aerated through the said aeration opening in the discharge head, so that the air flowing in comes into direct contact with the liquid. Such a design usually has a riser pipe on the discharge head, which protrudes from its base into the liquid reservoir. However, a design is also conceivable in which a bag, in which the liquid is stored, is provided within the rigid wall of the liquid reservoir. The ventilation does not take place in this bag, but in a surrounding space within the rigid wall of the liquid reservoir. Depending on the design, a riser pipe can be dispensed with in such a bag system.

When the liquid dispenser is delivered, the liquid reservoir is filled with a pharmaceutical or cosmetic liquid. In particular, it can be a highly viscous liquid in the form of a gel or a foam.

BRIEF DESCRIPTION OF THE DRAWINGS

• Fig. 1 zeigt einen erfindungsgemäßen Flüssigspender in einer Gesamtdarstellung.
• Fig. 2 zeigt den erfindungsgemäßen Austragkopf des Flüssigkeitsspenders gemäß Fig. 1 in geschnittener Darstellung.
• Fig 3 zeigt die wesentlichen Komponenten des Austragkopfes in einer Explosionsdarstellung.
• Fig. 4 verdeutlicht den besonderen Aufbau der Basis zur Gewährleistung eines reproduzierbaren Öffnungsverhaltens eines Belüftungsventils des Austragkopfes.
• Fig. 5 bis 6B verdeutlichen die Verformung einer Ventillippe des Belüftungsventils während der Belüftung.
• Fig. 7 zeigt den inneren Aufbau des Betätigungsdrückers des Austragkopfes.
• Fig. 8 und 9 zeigen den Aufbau eines als Balg ausgebildeten Pumpkammerbauteils.
• Fig. 10A und 10B zeigen eine zweite Variante eines Austragkopfes, im unbetätigten und im betätigten Zustand.

Further advantages and aspects of the invention result from the claims and from the following description of preferred exemplary embodiments of the invention, which are explained below with reference to the figures.

• 1 shows a liquid dispenser according to the invention in an overall view.
• 2 shows the discharge head according to the invention of the liquid dispenser according to FIG 1 in cut representation.
• figure 3 shows the main components of the discharge head in an exploded view.
• 4 illustrates the special structure of the base to ensure a reproducible opening behavior of a ventilation valve of the discharge head.
• Figures 5 to 6B illustrate the deformation of a valve lip of the ventilation valve during ventilation.
• 7 shows the internal structure of the operating button of the discharge head.
• Figures 8 and 9 show the structure of a pump chamber component designed as a bellows.
• Figures 10A and 10B show a second variant of a discharge head, in the unactuated and in the actuated state.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

1 shows a liquid dispenser 100 for dispensing pharmaceutical or cosmetic liquids, for example for dispensing a shower gel. The liquid dispenser 100 has a liquid reservoir 110 and a dispensing head 10 which is attached to a bottle neck or storage nozzle of the liquid reservoir 110 by means of a thread or some other connection technique.

The discharge head 10 has a base 20 and an actuating pusher 50 which can be depressed in relation to the base 20 in the direction of an actuating direction 2 . A discharge opening 52 is provided on this. By depressing the actuating pusher 50 , a pump device 12 provided in the discharge head 10 is actuated, which conveys liquid from the liquid reservoir 110 to the discharge opening 52 .

In 2 the discharge head 10 is shown in more detail. Referring to this 2 and the exploded view of the 3 the elements are explained in detail.

The main elements of the discharge head 10 are the already mentioned base 20, the actuating button 50 and a pumping chamber component 80 which is provided for attachment to both the base 20 and the actuating button 50 and which provides a pumping chamber wall in the form of a bellows 81. How based on 2 As can be seen, the pump chamber component 80 made of an elastically deformable plastic is clamped by means of a sleeve-shaped fastening section 82 on a clamping surface 40 of an inlet connection 32 of the base 20, with this Inlet connection 32 is penetrated by a liquid inlet 22 . On the opposite side, the pump chamber component 80 is fastened to the actuating button 50 with a fastening flange 84 , this fastening being effected on the inside of a circumferential fastening web 68 of the actuating button 50 .

Together with the base 20 and the actuating pusher 50, the pumping chamber component 80 forms a total of three valves. An intake valve 14 is provided at the upper end of the intake port 32 . Here, the pump chamber component 80 has an elastically deflectable hemispherical valve body 88 which is pressed against the liquid inlet 22 and opens when the pressure in the pump chamber 13 is negative. At the opposite end, the pump chamber component 80 has a valve lip 86 which rests against an annular web 72 of the actuating pusher 50 on the outside. In the event of excess pressure in the pump chamber 13, the valve lip 86 is deflected, in particular in the area of the discharge opening 52, so that liquid can flow to the discharge opening 52 and into a surrounding atmosphere.

The third valve, which is formed by the pump chamber component 80, is a ventilation valve 18. This is formed on the one hand by a circumferential valve bridge 42 of the base 20 and its inwardly pointing valve surface 44 and on the other hand by a conically widening valve lip 90 of the pump chamber component 80. At the free end, this valve lip has a contact surface 94 for abutting against the valve surface 44 .

The ventilation valve 18 separates a surrounding atmosphere from an annular space surrounding the inlet connector 32 which is connected to an interior of the liquid reservoir 110 via ventilation openings 28 . If the pressure in the liquid reservoir 110 and thus also in the annular space is lower than an ambient pressure, the ventilation valve 18 opens, in that the valve lip 90 at least partially loses contact with the valve surface 44 .

Liquid is discharged by depressing the actuating pusher 50 by applying force to an actuating surface 54 so that the bellows 81 of the pump chamber component 80 is compressed and the liquid contained therein flows out through the discharge opening 52 after the outlet valve 16 has opened. If the actuating pusher 50 is then released, it returns to its starting position, with the previously elastically stressed pump chamber component 80 being deformed back 2 back, meanwhile the outlet valve 16 is closed and instead the inlet valve 14 opens, so that liquid can flow from the liquid reservoir 110 into the pump chamber 13 .

The ventilation valve 18 is provided so that no negative pressure arises in the liquid reservoir 110 after liquid has been removed, which would prevent liquid from flowing back into the pump chamber 13 . This opens when the pressure in the liquid reservoir 110 is negative, in that the contact surface 94 on the side of the valve lip 90 opposite the valve lip root 92 is lifted off the valve surface 44 and thus allows ambient air to flow in.

Particular aspects of the discharge head 10 are described below with reference to the Figures 4 to 10B explained.

4 shows a sectional representation of the base 20 in a separate representation. An internal thread 34 is provided on the base 20 by means of which the base is fastened to a thread of the liquid reservoir 110 . If the discharge head 10 is screwed tightly onto the liquid reservoir 110, there is a risk that a top wall 24 of the base 20 spanning the bottleneck of the liquid reservoir 110 will be subjected to tension in a way that impairs the opening properties of the ventilation valve 18, in particular the contact pressure of the contact surface 94 of the valve lip 90 on the valve surface 44 lowers in such a way that the ventilation valve 18 remains permanently open and liquid loss is to be feared here, or increases the contact pressure in such a way that the ventilation valve 18 does not open reliably, so that a negative pressure can build up in the liquid reservoir 110 .

The base of the discharge head has two measures to prevent such a stress condition. On the one hand, a reinforcement structure 26 in the form of a circumferential web is provided on the upper side of the top wall 24 . This is radially above that surface against which an uppermost rim of the bottleneck will be pressed when the base 20 is screwed onto the bottleneck. It has been shown that such a reinforcement brings about a decoupling, so that the induced state of stress can only reach the valve bridge 42 to a small extent and can therefore only deform it to a small extent. The second measure is that the circumferential valve bridge 42 continues to below the level of the top wall 24 and here forms a circumferential wall section 46 aligned therewith. The valve bridge 42 and the wall section 46 together form a sleeve shape. This also counteracts the deformation of the valve bridge 42 . Even if the base 20 is improperly screwed tightly onto the bottleneck of the liquid reservoir 110, the behavior of the ventilation valve 18 hardly changes.

the Figures 5 and 6A and 6B illustrate another aspect with regard to the ventilation valve 18. In order to allow the ventilation valve to close reliably, it is advantageous if the valve lip 90 of the ventilation valve 18 has a conical shape with a widening in the direction of the contact surface 94 of the valve lip 90. However, this conical shape has the disadvantage that the valve lip 90 has to be deformed for the purpose of opening the ventilation valve 18, in the course of which the contact surface 94 of the valve lip 90 is shortened so that it detaches at least in sections from the valve surface 44 of the valve bridge 42.

In order to promote this deformation, the in figure 5 A support structure 36 with ribs 39 is provided on the outside of the inlet connection piece 32 as shown, which each form support surfaces 38 on their upper side.

These support surfaces 38 promote valve opening, since deformation of valve lip 90 is made more difficult in the area of support surfaces 38, so that at the same time in the circumferential areas between two ribs 39 with support surfaces 38, the deformation of valve lip 90 is promoted and here at least compared to that caused by support surfaces 38 supported areas is facilitated.

the Figures 6A and 6B show this, the figures showing the base 20 and only the valve lip 90 of the pumping chamber component 80 .

Figure 6A 12 shows the state of the closed ventilation valve 18. The valve lip 90 is also shown separately here again for better understanding. When the ventilation valve is closed, the contact surface 94 rests against the outside valve surface 44 and has a rotationally symmetrical shape.

Now arises a negative pressure in the liquid reservoir 110, this causes this in the Figure 6B clearly show a deformation of the valve lip 90 in the intermediate areas and thus a detachment of the contact surface 94 of the valve lip 90 in these areas. Air from the environment can thus flow into the liquid reservoir 110 .

7 shows the actuating button 50 in a separate representation and with a perspective from below into the actuating button 50 . The outer fastening web 68 can be seen, on the inside of which the fastening flange 84 of the pump chamber component 80 is fixed.

An annular web 72 is provided within this, the outer surface of which forms the valve surface 74 against which the valve lip 86 of the outlet valve 16 rests in the rest state. A displacement structure 60 on the end wall 56 of the actuating pusher 50 is also provided within this. On the one hand, this displacement structure 60 serves the purpose of reducing the pumping chamber volume. On the other hand, with its receiving space 64, which is surrounded by a peripheral wall 62, it forms a receiving area for residual air in the pump chamber 13. It has been shown that in practice it is difficult to completely displace the air from the pump chamber 13 . Since the pumping chamber volume remains comparatively large even when the actuating pusher 50 is depressed, a quantity of air initially present in the pumping chamber 13 remains at least partially in the pumping chamber when the dispenser is put into operation and while it is being used. However, the displacer structure 60 ensures that a considerable part of this quantity of air reaches the receiving space 64 and remains there permanently. This prevents this amount of air from negatively affecting the reproducible opening and closing of the outlet valve 16 . Said wall 62 of the displacement structure 60 extends into the bellows area 81 of the pump chamber component 80 and protrudes beyond the annular web 72.

the Figures 8 and 9 show the pump chamber component in an isolated representation, with in 9 the pumping chamber component is shown in section while in 8 is shown as a whole.

It can be seen that the valve lip 90 assigned to the inlet valve 14 is protected in a special way against injuries prior to assembly. This is advantageous since the pump chamber component 80 is preferably handled as bulk material during assembly, ie a large number of such pump chamber components 80 are handled without a defined alignment with one another, for example transported and supplied. In particular, common storage and common transport in a large bag with a large number of pump chamber components 80 are common. There is a very high risk that damage to the contact surface 94 at the distal end of the valve lip 90 will result in the ventilation valve remaining permanently open during operation.

In order to prevent this, a protective lip 96 is provided, which is also an integral part of the pump chamber component 80 and which extends over the contact surface 94 of the valve lip 90 both in the radial direction and in the axial direction. The contact surface 94 is thus set back in relation to the lower end face of the protective lip 96 .

the Figures 10A and 10B 12 show a second exemplary embodiment of a discharge head 10 according to the invention. This is essentially identical in design to the exemplary embodiment in the preceding figures, with the exception of the detail mentioned below. The only difference is that the fastening web 68, on the inside of which the upper end of the pumping chamber component 80 is fastened, is already at rest Figure 10A substantially further towards the lower end of the pump chamber member 80 extends.

This design was chosen so that an end face terminating the fastening web 68 at the lower end can act as a button 70 which, when the actuating pusher 50 is pressed down, forces the ventilation valve 18 to open or at least reduces the contact pressure of the contact surface 94 of the valve lip 90 and the valve surface 44 in such a way that the Opening the ventilation valve 18 can be guaranteed for the purpose of producing the pressure equalization.

Figure 10B shows this effect. In the figure, the lower end position of the actuating pusher 50 is shown. In this lower end position, the button 70 presses on the outside of a tilting collar 98, which is also the carrier of the protective lip 96 described above. The arrows 4 make this clear. The deformation of the tilting collar 98 brought about by this means that the valve lip 90 attached to the inner end of this tilting collar 98 detaches from the valve face 44 . The arrows 6 illustrate this. This opening works particularly well when consistent with the previous embodiment and in particular that there figure 5 said ribs 39 are provided with their respective support surfaces 38.

So when the actuating pusher is pushed into its lower end position, the ventilation valve 18 is thereby opened. If there is still a negative pressure in the liquid reservoir 110 from a previous actuation, it is equalized at this moment. It is true that during the return stroke of the actuating pusher 50 a renewed negative pressure may arise in the liquid reservoir. However, this is not sufficient to prevent liquid from being sucked into the pump chamber 13 during the return stroke. With the next actuation, the negative pressure in the liquid reservoir is equalized again.

Claims (15)

1. Discharge head (10) for a liquid dispenser (100) for the discharge of pharmaceutical or cosmetic liquids with the following features:

   a. the discharge head (10) has a base (20) and an actuating button (50) which can be pressed down in relation to the base (20) in an actuating direction (2) between an unactuated end position as well as an actuated end position, and

   b. the discharge head (10) has a liquid inlet (22) for connection to a liquid reservoir and a discharge opening (52) for the discharge of liquid into a surrounding area, and

   c. the discharge head (10) has a pumping device (12) which comprises a deformable pumping chamber component (80) which is open on both sides, is fastened to the base (20) and to the actuating button (50), surrounds a variable-volume pumping chamber (13), and which has an inlet valve (14) and an outlet valve (16), and

   d. the discharge head has at least one aeration opening (28) which penetrates the base (20) and is assigned an aeration valve (18), and

   e. the aeration valve has a peripheral valve lip (90) which is moulded integrally on the deformable pumping chamber component (80) and bears in an outwardly prestressed manner against a peripheral valve bridge (42) of the base,

   characterized by the following further feature:
   f. a protective lip (96) is provided which is likewise moulded integrally on the deformable pumping chamber component (80) and is arranged on the outer side of the valve lip (90), in order to protect the valve lip (90) before installation into the discharge head (10).
2. Discharge head (10) according to Claim 1 with the following further feature:

   a. the protective lip (96) protrudes beyond the valve lip (90) radially and axially.
3. Discharge head (10) according to either of the preceding claims with the following additional features:

   a. the aeration valve (18) has, on the base (20), the peripheral valve bridge (42) which rises above a surrounding radially extending covering wall (24) of the base and the inner side of which forms a peripheral valve face (44), and a reinforcing structure (26) which is provided on an upper side of the covering wall (24), preferably in the form of a peripheral reinforcing web, is provided on the outer side on the surrounding covering wall (24), and/or

   b. the aeration valve (18) has, on the base (20), the peripheral valve bridge (44) which rises above a surrounding radially extending covering wall (24) of the base and the inner side of which forms a peripheral valve face (44), and the peripheral valve bridge (42) is part of a sleeve-shaped structure which forms the peripheral valve bridge (42) above the covering wall (24) and which continues below the covering face in a peripheral wall portion (46) which is flush with the valve bridge (42).
4. Discharge head (10) according to Claim 3 with the following further feature:

   a. the at least one aeration opening (28) is provided in an annular wall (48) which adjoins the wall portion (46) at the lower end.
5. Discharge head (10) according to Claim 3 or 4 with the following further feature:

   a. the discharge head (10) has, on the lower side of the covering wall (24), a bearing face (30), preferably provided with a seal, for a container neck of a liquid reservoir, the bearing face (30) being delimited on the inner side by way of the peripheral wall portion (46).
6. Discharge head (10) according to one of the preceding claims with the following additional features:

   a. the aeration valve (18) has, on the base (20), the peripheral valve bridge (42), the inner side of which forms a valve face (44), and,

   b. in order to fasten the pumping chamber component (80) to the base (20), the base (20) has an inlet stub (32) which forms the liquid inlet and onto which a fastening portion (82) of the pumping chamber component (80) is pushed, and

   c. the inlet stub (32) has a supporting structure (36) with at least one outwardly pointing and non-peripheral supporting face (38) which passes into touching contact with the pumping chamber component (80) at least towards the end of the pressing down of the actuating button (50), and brings it about as a result that a pressing force, with which the valve lip (90) bears against the valve face (44), is not uniform over the periphery.
7. Discharge head (10) according to Claim 6 with at least one of the following additional features:

   a. the supporting structure (36) has a plurality of supporting faces (38), and/or

   b. the supporting structure (36) has a plurality of ribs (39), the end faces of which, which point in the direction of the actuating button (50), form the supporting faces (38), and/or

   c. the at least one aeration opening (28) is arranged circumferentially between the ribs (39), and/or

   d. the valve lip (90) has a widening shape, a straight line between a contact face (94) at the distal end of the valve lip (90) and valve lip root (92) on the pumping chamber component (80) encloses an angle between 30° and 60° with the actuating direction (2).
8. Discharge head (10) according to one of the preceding claims with the following additional features:

   a. the outlet valve (16) has a peripheral annular web (72) which protrudes in the direction of the base (20) from an inner-side end wall (56) of the actuating button, and the outer side of which forms a peripheral valve face (74), and

   b. the discharge head (10) has, on the inner side of the annular web (72), a displacement structure (60) which protrudes from the inner-side end face of the actuating button, this displacement structure (60) having a receiving space (64) which is open in the direction of the pumping chamber (13) and is closed laterally by way of a surrounding wall (62).
9. Discharge head (10) according to Claim 8 with the following further features:

   a. the pumping chamber (13) has a maximum volume V_PMax which is defined by way of the interior space of the pumping chamber (13) between the inlet valve (14) and the outlet valve (16) in the case of an actuating button (50) which is arranged in the non-actuated end position, and

   b. the receiving space (64) has a receiving space volume V_A which is formed by way of that part volume of the pumping chamber which is enclosed within the surrounding wall (62), and

   c. the ratio between V_A and V_PMax is between 1:50 and 1:10.
10. Discharge head (10) according to Claim 8 or 9 with the following further feature:

    a. the surrounding wall (62) extends into the pumping chamber (13) so as to protrude beyond the annular web (72).
11. Discharge head (10) according to one of Claims 8 to 10 with the following further feature:

    a. the displacement structure (60) has a cross section orthogonally with respect to the actuating direction (2) which is smaller than an inside cross section of the pumping chamber component (80), in particular smaller than an internal diameter of a bellows region (81) of the pumping chamber component (80).
12. Discharge head (10) according to one of the preceding claims with the following additional features:

    a. a tilting limb (98) is provided which protrudes radially beyond the peripheral valve lip (90) and is moulded in one piece on the pumping chamber component (80), and

    b. a button face (70) which points in the direction of the tilting limb (98) is provided on the actuating button (50), which button face (70) loads the tilting limb (98) with force in the actuated end position and, as a result, lifts the valve lip (90) of the aeration valve from the valve bridge (42), or facilitates pressure-induced lifting of the valve lip (90) from the valve bridge (42).
13. Discharge head (10) according to one of the preceding claims with at least one of the following additional features:

    a. the discharge head has a thread (34) for fastening to the liquid reservoir (112), and/or

    b. the pumping chamber component (80) has a region which is configured as a bellows (81).
14. Liquid dispenser (100) for the discharge of pharmaceutical or cosmetic liquids with the following features:

    a. the liquid dispenser has a liquid reservoir, and

    b. the liquid reservoir has a discharge head,

    characterized by the following further feature:
    c. the discharge head is configured according to one of the preceding claims.
15. Liquid dispenser (100) according to Claim 14 with at least one of the following additional features:

    a. the liquid reservoir has an internal volume between 100 ml and 500 ml, and/or

    b. the liquid reservoir is filled with a cosmetic product, in particular a gel-like skin care product or haircare product.

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