WO2004056490A1

WO2004056490A1 - Dispenser with protected air conduit

Info

Publication number: WO2004056490A1
Application number: PCT/ES2002/000607
Authority: WO
Inventors: Francesc Xavier Gonzalez Fernandez; Pere Pares Montaner
Original assignee: Saint-Gobain Calmar S.A.
Priority date: 2002-12-20
Filing date: 2002-12-20
Publication date: 2004-07-08
Also published as: AU2002368479A1

Abstract

The invention relates to a dispenser with a protected air conduit. The inventive dispenser consists of (i) a mobile part comprising a head (1) and a rod (3) and (ii) a fixed part comprising a cover (7), which is designed to fix the dispenser to a container, and a casing (5). The aforementioned casing (5) defines an inner space that houses a piston (9) which is mounted to the rod (3) and which divides the inner space into a pumping chamber (11) and an upper space (13). Moreover, said casing (5) comprises a vent hole (15). The mobile part of the dispenser also comprises a second hole (33) which connects the upper space (13) of the casing (5) with the outside.

Description

DISPENSER WITH PROTECTED AERATION DUCT

DESCRIPTION

Field of the Invention

The invention relates to a dispenser with a protected aeration duct, which has a movable part that comprises a head and a stem, and a fixed part that includes a lid suitable for fixing the dispenser to a container and a chill, where the chill defines an interior space in which a piston mounted on the rod is housed and that divides the interior space into a pumping chamber and into an upper space, where the shell has an aeration hole.

State of the art

Dispensers of the type indicated above are known. They are used for the dosage of all kinds of liquids contained in the container. Usual applications are the dosage of soaps and other cleaning products, cosmetic products, food products, pharmaceutical products, etc.

By dispensing a certain amount of liquid to the outside, the volume of liquid contained in it is reduced inside the container. To compensate for this loss in volume, dispensers usually have an aeration duct that allows air to enter from the outside, thus preventing a vacuum from forming inside the container or collapsing the container. However, the existence of this aeration duct carries the risk of other fluids entering the interior of the container, such as water.

Usually the aeration duct is arranged between the movable part and the fixed part, so that a space is defined between the facing and relative moving surfaces of the movable part and the fixed part. tion. However, this aeration duct is relatively accessible, so that unwanted fluids, such as water, can be introduced through it.

In some cases, attempts have been made to solve this problem by adding walls that surround the duct to the mobile part and the fixed part, which form a protective labyrinth that prevents water from entering the duct. However, the inclusion of these walls requires the design of an entire dispenser assembly with a greater height, which conditions the aesthetics of the dispenser and also has a negative influence on costs.

There is therefore a need to find solutions that prevent the entry of water or other unwanted fluids into the aeration duct that do not adversely affect the aesthetics of the dispenser or the manufacturing costs. In particular, it is convenient to find solutions that allow the design of reduced height dispensers.

Summary of the invention

The invention aims to overcome these drawbacks. This purpose is achieved by means of a dispenser of the type indicated at the beginning, characterized in that the mobile part has a second hole that communicates the upper space of the shell with the outside.

Indeed, the mobile part always has the head at its upper end, which, for ergonomic reasons, is larger than the stem. Therefore the head can form an "umbrella effect" with respect to the environment just below it. Therefore if the second hole is arranged in this environment, this second hole will be protected by said "umbrella effect". However, the fixed part must necessarily be away from the head, since the head must be able to move vertically to perform the pumping movement. Therefore the second hole cannot be in the fixed part, nor can it be partially formed by the fixed part, as it is known in the state of the art, but the second hole must be totally integrated in the part mobile. In this way the second hole moves together with the head and can therefore be positioned in the environment under the head. In this way, a dispenser is obtained with a protected aeration duct and without the design constraints imposed by the inclusion of protection walls such as those known in the state of the art.

A preferred embodiment of the invention is obtained when:

[a] the head has a lower annular wall and the stem has an annular groove facing the head, where the annular groove is suitable to accommodate, at least partially, the lower annular wall, where the annular groove has a base and an outer wall,

[b] the second hole passes through the base of the annular groove, and

[c] between the annular wall and the outer wall there is an intermediate space that allows air to pass from the outside to the second hole.

Indeed, a preferred way of mounting the assembly formed by the stem and the head is obtained when the head has a lower annular wall in its lower part and the stem has an annular groove facing the head. The lower annular wall is housed in the annular groove and is secured by some means of gluing. The stem is substantially a cylindrical tube through which the pumped liquid passes. And the annular groove is obtained by having an outer wall that circumscribes the stem and which is separated from it by a distance approximately equal to the thickness of the lower annular wall of the head. The outer wall is attached to the stem through a base which is a small transverse partition that extends between the outer wall and the stem. With this geometry it is possible to locate the second hole in the base and to provide an intermediate space between the annular wall and the outer wall that communicates the outside with the second hole, so that air can pass into the dispenser, specifically to the upper space . From there, air can pass into the container through the vent hole. Preferably the cover has a sealing lip of the same material as the cover, which forms a seal between the fixed part and the mobile part. In fact, in state-of-the-art dispensers between the fixed part and the mobile part, a watertight closure is usually not necessary, since the entire perimeter of contact between the fixed part and the mobile part can be used to allow air to enter the duct. aeration. However, in the case of the present invention, it is convenient that there is a watertight seal between the fixed part and the mobile part, since it is convenient to avoid the possibility of water entering this area. A preferred way to achieve this sealing is by including said sealing lip, which is preferably the same material as the cover. This allows the assembly to be a single piece obtained with a single manufacturing process (for example by injection). Alternatively, it is possible that the sealing lip is made of a material other than the cover, such as an elastomeric material, which can be bi-injected onto the cover. The decision between one or the other alternative will depend on the design and cost constraints of each specific solution. In the case of a sealing lip of the same material as the cap, which is preferably polypropylene, the necessary sealing characteristics must be achieved by suitably combining parameters such as the thickness of the lip, its angle of attack and the interference between the lip and the mobile part. In the case of a lip made of elastomeric material, the elastic qualities of the material can be used to optimize the tightness obtained. In general, it is advantageous for the sealing lip to interfere with the moving part between 0.1 and 0.3 mm. It is also advantageous for the sealing lip to have a thickness of between 0.1 and 0.5 mm and to come into contact with the moving part with an angle of attack of between 30 ° and 60 °.

Brief description of the drawings

Other advantages and characteristics of the invention are appreciated from the following description, in which, without any limiting character, a preferred embodiment of the invention is described, making reference to the accompanying drawings. The figures show: Fig. 1, a view of a longitudinal section of a dispenser with aeration duct according to the state of the art.

Fig. 2, an enlarged view of the contact area between the mobile part and the fixed part of the dispenser of Fig. 1.

Fig. 3, a view of a cross section along the line lll-lll of the dispenser of Fig. 1.

Fig. 4, a view of a longitudinal section of a dispenser with aeration duct protected according to the state of the art, Fig. 5, an enlarged view of the contact area between the mobile part and the fixed part of the dispenser of Fig. 4.

Fig. 6, a cross-sectional view along line VI-VI of the dispenser of Fig. 4.

Fig. 7, a view of a longitudinal section of a dispenser with a protected ventilation duct according to the invention.

Figs. 8 and 9, an enlarged view of two alternatives of the contact area between the mobile part and the fixed part of the dispenser of Fig. 7,

Fig. 10, a cross-sectional view along line X-X of the dispenser of Fig. 7.

Detailed description of an embodiment of the invention

In Figs. 1 to 3 and 4 to 6 show dispensers that are part of the state of the art. In general, the dispensers comprise a head 1, a stem 3, a casing 5, and a cap 7. The casing 5 forms the pump body of the dispenser and defines an interior space inside. The stem 3 is partially inserted into the shell 5. Inside the shell 5, and mounted on the stem 3 is a piston 9 that moves jointly with the stem 3 in a manner known to a person skilled in the art. The piston 9 divides the interior space into two parts: a pumping chamber 11 and an upper space 13. The shell 5 has an aeration hole 15 that communicates the upper space 13 with the interior of the container on which the dispenser. The shell 5 is jointly attached to the lid 7 forming the fixed part of the dispenser, which is attached jointly to the container. From the upper end of the shell 5 protrudes the stem 3 on whose top end the head 1 is mounted. The stem 3 and the shell 5 move in the vertical direction during actuation of the dispenser, and thus form the moving part of the dispenser. The dispenser comprises other elements, such as, for example, the aforementioned piston 9, or for example a spring 17 that tends to move the rod 3 towards its extended position, the assignment of which to the aforementioned fixed part and mobile part is not relevant in face Therefore, with regard to the present invention, it should not be interpreted that the moving part is solely and exclusively composed of the stem 3 and the head 1, nor that the fixed part is solely and exclusively composed of the cover 7 and the shell 5.

In Fig. 1 the path followed by the air as it is sucked through the aeration duct is shown as a hatched area. The air passes through a gap between the stem 3 and the lid 7, as clearly seen in Fig. 2. The air travels through the upper space 13 to the aeration hole 15 and enters the interior of the container. As can be seen, it is possible that in the vicinity of the contact area between the fixed part and the mobile part of the dispenser there is water that can be sucked inwards.

In Figs. 4 to 6 a dispenser very similar to that of Figs. 1 to 3, but which has the aeration duct protected by walls that define a labyrinth. The cap 7 has a first annular wall 19 that flanges the stem 3. The head 1 has a second annular wall 21 that flanges the first annular wall 19. Between the stem 3, the first wall 19 and the second wall 21 there are gaps large enough to allow the passage of air, as can be clearly seen in Figs. 5 and 6. In Fig. 4 the path followed by the air as it is sucked through the suction line has been shown again as a hatched area. Air passes through the gap between the first wall 19 and the second wall 21, then passes through the gap between the first wall 19 and the stem 3 until reaching the upper space 13. From the upper space 13 it passes into the container a through the aeration hole 15. As can be seen in this case, the aeration duct is more protected than in the dispenser of Fig. 1 and it is more difficult for water to enter the interior of the container. Without However the introduction of these walls 19 and 21 forces to increase the height of the dispenser.

In Figs. 7 to 10 a preferred embodiment of a dispenser according to the invention is shown. The basic structure of the dispenser is very similar to that of the dispensers in Figs. 1 and 4, and equal reference numbers have been used for the equivalent parts.

The head 1 has a lower annular wall 23 and the stem 3 has an annular groove 25 facing the head 1 and which is formed by an outer wall 27 and a base 29. The stem 3 is substantially a tube through which the liquid pumped from the pumping chamber 11 to an outlet duct 31 arranged in the head 1. The outer wall 27 surrounds the stem 3 and is attached to the stem 3 through the base 29, which is a small protruding partition. radially of the stem 3. Between the outer wall 27 and the outer surface of the stem 3, the annular groove 25 is defined, which is suitable for housing the lower annular wall 23 of the head 1. The base 29 has two second holes 33. Following said second holes 33 there are intermediate spaces 35 that allow air to come from the outside to said second holes 33. Once the air has reached said second holes 33, it can move along the es upper space 13 to the vent hole 15, as symbolized by the hatched area in Fig. 7.

As can be seen, the air inlet is housed just below the widened part of the head 1. In this way it is almost impossible for water to enter the device. However, no condition is imposed on the design of the dispenser, as was the case with the incorporation of the first wall 19 and the second wall 21.

With a pump according to the invention, it is no longer necessary that there is a gap between the moving part and the fixed part that allows air to pass through. It is even advantageous if the fixed part and the mobile part are in contact with each other in a watertight way, to further reduce the risk of water entering the dispenser. In the embodiment of Figs. 7 to 10 this sealing is resolved by means of sealing lips 37 (Figs. 8 and 9) which can be either of the same material as the cover 7, as shown in Fig. 9, or of a different material, in which case the cover 7 - sealing lip 37 assembly is preferably manufactured by biinjection.

Claims

1. Dispenser with protected aeration duct, which has a moving part comprising a head (1) and a rod (3), and a fixed part comprising a lid (7) suitable for fixing said dispenser to a container and a nozzle (5), wherein said nozzle (5) defines an interior space in which a piston (9) mounted on said rod (3) is housed and divides said interior space into a pumping chamber (11) and in an upper space (13), and where said shell (5) has an aeration hole (15), characterized in that said mobile part has a second hole (33) that communicates said upper space (13) of said shell (5) with the outside

2. Dispenser according to claim 1, characterized in that:

[a] said head (1) has a lower annular wall (23) and said rod (3) has an annular groove (25) facing said head (1), where said annular groove (25) is suitable for housing, at least partially, said lower annular wall (23), wherein said annular groove (25) has a base (29) and an outer wall (27),

[b] said second hole crosses said base (29), and

[c] between said annular wall and said outer wall (27) there is an intermediate space (35) that allows the passage of air from the outside to said second hole (33).

3. Dispenser according to one of claims 1 or 2, characterized in that said lid (7) has a sealing lip (37) of the same material as said lid (7), said sealing lip (37) forming a tight seal between said fixed part and said mobile part. 40-

4. Dispenser according to one of claims 1 or 2, characterized in that said cover (7) has a sealing lip (37) of elastomer material bi-injected on said cover (7), said sealing lip (37) forming a tight seal between said fixed part and said mobile part.

5. Dispenser according to one of claims 4 or 5, characterized in that said sealing lip (37) has an interference with said moving part comprised between 0.1 and 0.3 mm.

6. Dispenser according to any of claims 3 to 5, characterized in that said sealing lip (37) has a thickness between 0.1 and 0.5 mm and that said sealing lip (37) comes into contact with said part mobile with an angle of attack between 30 ° and 60 °.