FLUID DISPENSER AND METHOD FOR MANUFACTURING A FLUID DISPENSER

Abstract

Method for manufacturing a fluid dispenser. In a finished state, the fluid dispenser has a fluid store and a delivery opening through which fluid is discharged to the environment in a delivery direction. The fluid dispenser has a housing component through which the delivery opening is made and which has a delivery structure forming the delivery opening and/or adjoining the delivery opening, for influencing a delivery characteristic. This housing component having the delivery opening is manufactured firstly by manufacturing a base body by plastic injection moulding in a casting mold and then, in a region of a provisional delivery structure of the base body, a mechanical force is applied to deform the provisional delivery structure and hence create a definitive delivery structure.

Claims

1. A method for manufacturing a fluid dispenser having a fluid store, a delivery opening through which delivery opening fluid is discharged to the environment in a delivery direction, and a housing component penetrated by the delivery opening and which housing component has a delivery structure forming the delivery opening and/or adjoining the delivery opening, for influencing a delivery characteristic, the method comprising manufacturing the housing component penetrated by the delivery opening firstly by manufacturing a base body by plastic injection moulding in a casting mould and then, in a region of a provisional delivery structure of the base body, applying a mechanical force to deform the provisional delivery structure and hence creating a definitive delivery structure.

2. The method according to claim 1, wherein the mechanical force is applied with a protective cap of the fluid dispenser which protective cap, on the inside, has a widening structure tapering from the outside in a direction of the delivery opening and adapted to the provisional form of the delivery structure of the base body such that the widening structure is widened in the manner of a cup.

3. The method according to claim 1 wherein the mechanical force is applied with a die.

4. The method according to claim 3, wherein the mechanical force is applied with a heated die and/or after heating of the housing component.

5. A fluid dispenser, the fluid dispenser comprising: a fluid store; a delivery opening through which fluid is discharged to the environment in a delivery direction; and a housing component penetrated by a delivery opening and having a delivery structure adjoining the delivery opening and surrounding a discharge path, for influencing a delivery characteristic, the delivery structure having a circumferential depression on an outside thereof.

6. The fluid dispenser according to claim 5, wherein: the fluid dispenser is formed as a droplet dispenser; and the delivery structure forms a droplet formation surface on which droplet formation surface fluid discharged through the discharge opening adheres to form a droplet until the droplet detaches under force of gravity.

7. The fluid dispenser according to claim 6, wherein the droplet formation surface is delimited on an outside by a tear-off edge, wherein the tear-off edge is formed with a curvature radius of more than 0.05 mm.

8. The fluid dispenser according to claim 5, wherein the delivery structure has on the outside an external widening region, the external widening region widening continuously in the delivery direction.

9. The fluid dispenser according to claim 5, wherein the delivery structure has on an inside an internal widening region, the internal widening region widening in the delivery direction.

10. The fluid dispenser according to claim 5, wherein: the fluid dispenser has a removable and refittable protective cap covering the delivery opening when fitted; and the protective cap has an inwardly pointing widening structure lying against an inside of the delivery structure when the protective cap is fitted.

11. The fluid dispenser according to claim 5, wherein the delivery opening and/or the delivery structure has a shape deviating from rotational symmetry.

12. The fluid dispenser according to claim 5 wherein: the fluid dispenser is configured as a pump dispenser and has a manually actuatable pump device with a pump chamber and with an inlet valve and an outlet valve; or the fluid dispenser is configured as a squeeze bottle dispenser and has as a fluid dispenser a squeeze bottle compressible manually for delivery purposes.

13. The fluid dispenser according to claim 5, wherein: the fluid store is filled with a pharmaceutical fluid; and/or the fluid store has an internal volume of less than 200 ml.

14. The method according to claim 1, wherein the mechanical force is applied with a metallic die.

15. The method according to claim 4, wherein a temperature of the die or housing component corresponds at least to the Vicat softening temperature of the material of the housing component.

16. The fluid dispenser according to claim 6, wherein the droplet formation surface has an outer diameter of at least 1 mm and/or at most 3 mm.

17. The fluid dispenser according to claim 8, wherein an angle between a surface of the external widening region and the delivery direction is more than 20?.

18. The fluid dispenser according to claim 9, wherein an angle between a surface of the external widening region and the delivery direction is smaller than an angle between a surface of the internal widening region and the delivery direction.

19. The fluid dispenser according to claim 10, wherein the protective cap is formed as a screw cap and/or the delivery structure is held under elastic tension by the widening structure when the protective cap is fitted.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Further advantages and aspects of the invention arise from the claims and the following description of preferred exemplary embodiments of the invention which are explained below with reference to the figures.

[0045] FIG. 1 shows a fluid dispenser according to the invention in a sectional illustration.

[0046] FIG. 2 shows the region of the delivery opening of the fluid dispenser in an enlarged view.

[0047] FIGS. 3 and 4 show the use of the fluid dispenser in various orientations.

[0048] FIGS. 5A to 5F show a method for manufacturing a fluid discharge part 14 of the dispenser 10, and FIG. 5G shows the die removed.

[0049] FIG. 6 shows a fluid dispenser which is manufactured by means of a partially alternative method.

DETAILED DESCRIPTION

[0050] FIG. 1 shows a fluid dispenser 10 extending linearly in the direction of a main extent axis 2, in the present case for example a droplet dispenser. The fluid dispenser 10 has a delivery head 11 to which a fluid store 12 is coupled by means of a latch connection. Within the delivery head 11, a pump device 16 is provided which can be actuated via an actuation button 17 provided on the side of the outer housing 13 of the delivery head 11, and which, when actuated, draws in fluid from the fluid store 12 and conveys it in the direction of the delivery opening 30. FIG. 2 shows the region of the delivery opening 30 in an enlarged illustration.

[0051] The delivery opening 30 is part of a fluid discharge part 14. This is attached to an inner component 18 of the dispenser 10 and delimits the fluid path to the delivery opening 30. It has a sleeve-like portion which penetrates through an opening in the outer housing 13, and at the end of which a delivery structure 40 is provided, as explained in more detail below.

[0052] Inside the fluid discharge part 14, a valve body 19 is provided which is pressed by a coil spring 20 in the direction of the delivery opening 30 and closes the delivery opening 30 in a closed state. Only when the fluid pressure in the region between the pump device 16 and the delivery opening 30 has reached a sufficient pressure level does the outlet valve open by displacement of the valve body 19 against the spring force of the coil spring 20, and fluid can emerge.

[0053] FIG. 2 clearly shows the delivery structure 40 in the region of the delivery opening 30. The delivery structure 40 means the geometry of regions of the fluid discharge part 14 which surround or adjoin the delivery opening 30 and influence the form of the discharge.

[0054] In the present case, the delivery structure 40 is designed for discharging droplets. The delivery structure is rotationally symmetrical to the main extent axis 2 and has a substantially cup-like design, which is delimited primarily by an internal widening region 52 widening in the direction of the delivery direction 2A, and an external widening region 50 also widening in the direction of the delivery direction 2A.

[0055] On the outside, a circumferential depression 42 is provided. This is a type of constriction from which the fluid discharge part 14 widens in both directions.

[0056] As FIG. 3 illustrates, the inner widening region 52 forms a droplet formation surface 44. Fluid discharged through the delivery opening 30 is initially deposited in the area of this widening region 52, until the resulting droplet has reached a mass which separates it from the delivery structure 40 under the force of gravity. The widening region 52 and the end face of the delivery structure 40 together form a droplet formation surface 44.

[0057] The circumferential depression 42 allows provision of the illustrated angle B on the outside of the distal end of the fluid discharge part 14. This angle B, which is preferably smaller than the angle A between the main extent axis 2 and the inner widening region 52, is advantageous for preventing the fluid from not only collecting in the widening region 52 and on the end face, but also from passing around the distal outer edge into the external widening region 50. This guarantees that the fluid quantity of a droplet 100 does not deviate from the intended fluid quantity.

[0058] FIG. 4 illustrates that the angle A plays a greater role if the droplet dispenser is held obliquely during droplet discharge. If this is the case, the tendency of the fluid to pass from the inner droplet formation surface 44 to the outer widening region 50 is increased. The greater the angle A, the less critical such an oblique orientation is with respect to achieving a uniform droplet volume.

[0059] The described design of the delivery structure 40 cannot simply be achieved by plastic injection moulding.

[0060] FIGS. 5A to 5G show a possible sequence for manufacturing of the fluid discharge part 14.

[0061] Firstly, a base body 14 is manufactured. This is achieved by plastic injection moulding. A casting tool 200 with two casting mould halves 202A and 202B is used, as shown in FIG. 5A. In the closed state in FIG. 5B, the two casting mould halves 202A, 202B form a cavity 204 which has the negative form of the base body 14. Liquid plastic is injected into this cavity 204, as shown in FIG. 5C.

[0062] After hardening of the plastic, the casting tool 200 is opened and the base body 14 can be removed. As evident from FIG. 5A, the two casting mould halves 202A, 202B are formed such that there are no undercuts which could hinder removal of the base body 14 from the mould. This can therefore be removed without deformation.

[0063] FIG. 5D shows the base body 14 after injection moulding. Since the separating boundary 206 lies on the far side of the delivery structure 40, which is still provisional in the state of FIG. 5D, this is free from burrs.

[0064] Starting from the state of FIG. 5D, a second step in manufacturing of the fluid discharge part 14 takes place. A die 220 with a conical tip is now advanced from the outside in the direction of the main extent axis 2, as illustrated in FIG. 5E.

[0065] As shown in FIG. 5F, this die 220 presses the provisional delivery structure 40 outward and thus deforms this plastically. In particular, at this time the base body 14 may be heated, either because of the preceding injection moulding step or because of a separate heating. Thus the tendency of the delivery structure 40 to deform plastically can be increased. In addition or alternatively to a prior heating of the base body 14, it is also conceivable to heat the die 220 itself.

[0066] The temperature to be selected here depends on the plastic used. Preferably, the temperature lies above the softening temperature of the respective plastic. In the case of polypropylene, this temperature is for example around 150? C.

[0067] As soon as plastic deformation has taken place, the die 220 may be removed again as shown in FIG. 5G. This leaves the now complete fluid discharge part 14, the delivery structure 40 of which has the shape already illustrated in FIG. 2. The cup-like widening allows a particularly precise dosing since the discharged droplets differ only very slightly in their fluid volume.

[0068] FIG. 6 shows an alternative design. The distinguishing feature here is that the fluid discharge part 14 is initially left in the shape of the base body 14, and the plastic deformation is caused by a protective cap 60.

[0069] To this end, the protective cap 60 on its inside has a widening structure 62. Preferably, the protective cap as a whole, or at least the widening structure 62, is made of a harder material or a material with higher softening temperature than the material of the fluid discharge part 14.

[0070] When the protective cap 60 is fitted to the dispenser for the first time, preferably screwed on by means of a thread, this widening structure 62like the die 220 in the case of FIGS. 5A to 5Fpresses the delivery structure 40 outward and causes a plastic deformation. Preferably, this shaping takes place under the influence of heat. In particular, the fluid discharge part 14 may be at least partially heated when the protective cap 60 is fitted.