Self-closing dispensing head

Abstract

The invention relates to a self-closing dispensing head for a pressurised container having a dispensing valve for dispensing media, in particular viscous, self-foaming and/or gel-type products, the dispensing head (1) having an outlet (3) which can be closed by a closing element (6).

Claims

1. A self-closing dispensing head for a pressurized container, wherein the dispensing head comprises a dispensing valve for dispensing media, which dispensing valve comprises a dispensing orifice closeable by a closure element, an opening mechanism by which, in an assembled state, the dispensing orifice can be opened, and a channel for the media that opens into the dispensing orifice, wherein the channel comprises at least a first channel segment and a second channel segment and wherein, by pressure on an actuation element, the opening mechanism is actuated and the closure element, or a part of the closure element, and the second channel segment are moved relative to each other in such a way that a fluid passage is opened at the dispensing orifice to allow a flow of media from the container through the first and second channel segments and through and out of the dispensing orifice, the closure element being configured as a movable closure piston comprising a stiff cylindrical shaft with at one end at least one element for securing the closure piston in the second channel segment and/or at a transition from the first channel segment to the second channel segment, and the cylindrical shaft, at an end remote from the securing element, comprising a valve head which is dimensioned such that the dispensing orifice is securely closed, and wherein the closure piston is moved exclusively by hydraulic pressure, built up in the dispensing channel, of the media that is to be dispensed, and wherein (i) the closure piston comprises, on the cylindrical shaft of the closure piston, ribs or grooves oriented along a main axis of the cylindrical shaft; and/or (ii) the second channel segment comprises one or more notches and/or grooves along a main axis of the second channel segment, which notches and/or grooves increase a passage cross section of the dispensing channel; and/or (iii) starting from the first channel segment, one or more channel elements of smaller cross section than the second channel segment are arranged parallel to the second channel segment and open into the second channel segment before the dispensing orifice or open into the dispensing orifice.

2. The self-closing dispensing head of claim 1, wherein the closure piston comprises, on the cylindrical shaft of the closure piston, ribs or grooves oriented along a main axis of the cylindrical shaft.

3. The self-closing dispensing head of claim 1, wherein the second channel segment comprises one or more notches and/or grooves along a main axis of the second channel segment, which notches and/or grooves increase a passage cross section of the dispensing channel.

4. The self-closing dispensing head of claim 1, wherein starting from the first channel segment, one or more channel elements of smaller cross section than the second channel segment are arranged parallel to the second channel segment and open into the second channel segment before the dispensing orifice or open into the dispensing orifice.

5. The self-closing dispensing head of claim 1, wherein the second channel segment has a length of from 3 mm to 25 mm.

6. The self-closing dispensing head of claim 1, wherein the second channel segment has a length of from 5 mm to 20 mm.

7. The self-closing dispensing head of claim 1, wherein the elements for securing the closure piston in the dispensing channel comprise one or more barbs.

8. The self-closing dispensing head of claim 1, wherein the closure piston is constructed from different materials, the securing elements and the valve head consisting of a material that is more easily deformable than a material from which the cylindrical shaft is made.

9. The self-closing dispensing head of claim 8, wherein the valve head is made of one or more of a thermoplastic elastomer (TPE), silicone or low-density polyethylene (LDPE).

10. The self-closing dispensing head of claim 8, wherein the cylindrical shaft is made of one or more of acrylonitrile-butadiene-styrene terpolymer (ABS), polypropylene (PP) or polyoxymethylene (POM).

11. The self-closing dispensing head of claim 9, wherein the cylindrical shaft is made of one or more of acrylonitrile-butadiene-styrene terpolymer (ABS), polypropylene (PP) or polyoxymethylene (POM).

12. The self-closing dispensing head of claim 1, wherein the closure piston is produced by multi-component injection molding.

13. The self-closing dispensing head of claim 11, wherein the closure piston is produced by multi-component injection molding.

14. The self-closing dispensing head of claim 1, wherein the dispensing head is capable of dispensing viscous products.

15. The self-closing dispensing head of claim 1, wherein the dispensing head is capable of dispensing self-foaming products.

16. The self-closing dispensing head of claim 1, wherein the dispensing head is capable of dispensing gel-like products.

17. A pressurized container, wherein the container comprises the self-closing dispensing head of claim 1.

18. The container of claim 17, wherein the container contains a viscous product.

19. The container of claim 17, wherein the container contains a self-foaming product.

20. The container of claim 17, wherein the container contains a gel-like product.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further advantageous embodiments of the invention will become clear from further dependent claims, the description below and the drawings. In the drawings:

(2) FIG. 1a shows an illustrative embodiment of a dispensing head without inserted closure piston,

(3) FIG. 1b shows an illustrative embodiment of a dispensing head with inserted closure piston,

(4) FIG. 2 shows a section along the axis B-B in FIG. 1a,

(5) FIG. 3 shows an enlarged view of the inserted closure piston from FIG. 1b.

(6) In the drawing, parts having basically the same function are provided with corresponding reference numbers.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

(7) FIG. 1 shows the dispensing head 1, which is preferably configured in one piece. It has a housing 2 which is mounted on a container and a dispensing valve (not shown in detail) for dispensing media, for example viscous, self-foaming and/or gel-like products, or is connected in one piece thereto. This dispensing valve is assigned to the inner container space, into which the medium is filled, and can be operated by an opening mechanism by pressing on the actuation surface 8 of the dispensing head.

(8) The dispensing head has a dispensing orifice 3 which is in fluidic communication via a first channel segment 4 and a second channel segment 5. The closure element, which is configured as a closure piston 6 and closes the dispensing orifice 3, is assigned to the second channel segment.

(9) The closure piston 6 (FIG. 3) has a solid cylindrical shaft 6b, at one end of which a formation in the shape of a conical barb 6a made of a soft, flexible material is injection molded. At the end remote from the barb 6a, the shaft has a valve head 6c which is dimensioned such that the dispensing orifice is securely closed. According to the invention, the valve head is made of a soft, flexible material such that, when impinged by the flow of the medium that is to be dispensed, it is deformed and frees a ring-shaped gap for passage of the medium.

(10) During assembly, this closure piston 6 has been inserted through the dispensing orifice into the second channel segment of the dispensing channel and has been anchored by means of barbs 6a in the region of the transition from the first to the second channel segment.

(11) In the example shown, the shaft 6b of the channel segment 6 almost completely fills the second channel segment. FIG. 2 shows a cross section through the second channel segment 5. In the example shown, which represents a preferred embodiment, the second channel segment 5 has a cylindrical channel 5a, which is flanked by two cylindrical channels 5b and 5c of smaller diameter. The flanking channels 5b and 5c form the part of the second channel segment 5 through which the medium can flow from the first channel segment 4 to the dispensing orifice 3 when the closure piston 6 is inserted. By way of example, the figure shows two flanking channels, but in an advantageous embodiment of the invention it is expedient to use up to ten flanking channels, depending on the flow behavior of the medium. The opening of the dispensing orifice and the associated dispensing of the product from the dispensing head 1, and the subsequent re-closing of the dispensing orifice, are achieved by the elastic deformation of the valve head 6c, by virtue of the fact that the medium being conveyed builds up a hydraulic pressure in the dispensing channel.

(12) By actuation of the dispensing head 1, the container valve is opened and medium flows from the container through the valve and the first channel segment 4 into the fine auxiliary channels 5b and 5c of the second channel segment. In this process, the shaft of the closure piston is not moved from its position, and instead the product flows laterally with respect to the shaft inside the fine channels 5b and 5c as far as the end where the second channel segment in which the valve head 6c sits merges into the dispensing orifice.

(13) Inside the second channel segment 5, the system pressure increases on account of the product and acts perpendicularly with respect to the circumferential surface of the valve head 6c. Through the elasticity of the valve head 6c, the latter reacts with a slight deformation, as a result of which the cross section of the base of the truncated cone decreases. The surface fit between valve head 6c and dispensing orifice 3 is canceled, and a ring-shaped gap is produced through which the product can flow out. When the pressure inside the channel and against the circumferential surfaces of the valve head subsides, the valve head returns to its starting position and seals off the dispensing orifice again by means of the corresponding surface fit.

(14) According to the invention, the shaft 6b of the closure piston 6 is also provided with ribs or grooves applied along the main axis, such that the medium can flow through the channel segment 5. This represents an alternative to the flanking channels. However, in the case of more viscous media, it may be expedient to use both flanking channels and also grooves in the shaft.