EP2648853B1

EP2648853B1 - Trigger dispensing device with a supply valve

Info

Publication number: EP2648853B1
Application number: EP11813567.2A
Authority: EP
Inventors: Riccardo Alluigi
Original assignee: Guala Dispensing SpA
Current assignee: Guala Dispensing SpA
Priority date: 2011-02-16
Filing date: 2011-12-22
Publication date: 2015-09-23
Anticipated expiration: 2031-12-22
Also published as: EP2648853A1; WO2012110861A1; ES2557133T3

Description

The present invention relates to a trigger dispensing device for a liquid.
The known trigger dispensing devices envisage trigger-operated pumping means, which aspirate the liquid into a pumping chamber and dispense it outwards by means of a piston.
It is well known how for the jet of liquid dispensed to reach a good distance from the device and be well sprayed in fine drops, a pre-compression of the liquid is needed before dispensing.
Many trigger dispensing devices are known of with a pre-compression valve, also called supply valve, positioned between the pumping chamber and the liquid dispenser duct, as is disclosed in WO 0033970 .
However, such valves have numerous drawbacks: often, subjected to the pressure of the liquid, they cause a fall in the dispensing pressure on account of the leaks between the valves and the components supporting them.
The purpose of the present invention is to satisfy the aforementioned requirements and overcome, the drawbacks of the prior solutions, by making a trigger dispensing device with a supply valve which behaves optimally when opened.
Such purpose is achieved by a dispensing device according to claim 1.
The characteristics and advantages of the trigger dispensing device according to the present invention will be evident from the following description, made by way of a non-limiting example, with reference to the attached drawings, wherein:

figure 1 shows a cross-section view of the dispensing device according to the present invention, according to one embodiment;
figure 2 shows an enlargement of the area II in figure 1;
figures 3a and 3b show a respective rear and front view of a supply valve of the dispensing device in figure 1;
figures 4a and 4b show a respective rear and front view of an attachment element of the dispensing device in figure 1; and
figure 5 shows a cross-section view of a supply valve according to the present invention, according to yet a further embodiment.

A dispensing assembly for a liquid comprises a container, to contain the liquid to be dispensed, and a manually operated trigger dispensing device, mechanically connected to the container.
For example, the device 1 comprises a fastening 2 for connection to the neck of the container, for example for a threaded or bayonet connection.
The device 1 further comprises a frame 3, generally made in a relatively rigid frame material for the support of the other components.
In particular, the device 1 comprises pumping means suitable to aspirate the liquid from the container and to spray it outside the device itself.
For example, the pumping means comprise a pumping chamber 4 suitable for being placed in fluidic communication with the container; for example, the frame 3 comprises an aspiration duct 6 open at one end towards the container and such as to come out, at the opposite end, in the chamber 4.
The pumping means further comprise a piston 8, sealingly sliding in the chamber 4 s along a piston axis X.
For example, the frame 3 comprises a chamber wall 10a, for example cylindrical, with its axis coinciding with the piston axis X, which annularly defines the chamber 4, and an end wall 10b, for example perpendicular to the piston axis X, placed opposite the piston head 8, which defines the bottom of the chamber 4.
Preferably the aspiration duct 6 comes out in the pumping chamber 4 through the aspiration aperture 6a made in said end wall 10b.
Moreover, the device 1 comprises manually-operated actuation means, suitable for being moved to move the piston 8 in translation.
For example, the actuation means comprise a trigger 12, supported by the frame 3, for example hinged to it or translatable on it. The trigger 12 is engageable with the piston 8 to move said piston in translation.
The piston 8 slides in the chamber 4 between an initial rest or rearward or start stroke position, wherein the volume of the chamber 4 is maximum, and a final, or forward or end stroke dispensing position, wherein the volume of the chamber is minimum.
Preferably moreover, the actuation means comprise return means suitable for pushing the trigger towards the initial rest position. For example, said return means comprise an elastic element.
Furthermore, the device 1 comprises a dispensing duct 14 suitable for being placed in fluidic communication at an entrance aperture 14a with the pumping chamber 4 and, at an exit aperture 14b with the outside environment, to spray the liquid into the environment.
For example, the frame 3 comprises a duct wall 16 annular around a dispensing axis Z which annularly defines the dispensing duct 14.
The dispensing duct extends along the dispensing axis Z, preferably separate from and parallel to the piston axis X.
According to one embodiment, the entrance aperture 14a is delimited circumferentially by an axial boss or annular step (14c) projecting axially.
According to a further embodiment, the entrance aperture 14a is defined by the aperture generated by a bevel 14d placed at the end of the dispensing duct 14.
Moreover, at the entrance aperture 14a, outside the dispenser duct 14, the frame 3 comprises an attachment wall 17, for example an annular wall axial symmetric to the dispensing axis Z.
For example, the attachment wall 17 ends with an annular boss 17a which extends radially outwards so as to form an undercut.
Around the entrance aperture 14a, outside the dispenser duct 14, since the support wall 17 has greater radial dimensions than said entrance aperture 14a, a crown surface 18 is made which at least partially surrounds said entrance aperture 14a.
The crown surface 18 is interrupted by an intermediate passage 19 which comes out in the pressure chamber 4, to place said pressure chamber in communication with the dispensing duct 14.
Preferably moreover, the device 1 comprises a nozzle 20 applied to the output end 14b of the dispensing duct 14, to place the outgoing liquid in vortication or to finely nebulise it or to open/close the output of the dispensing duct.
One embodiment of such nozzle is described, for example, in document BS2010A000003 in the Applicant's name the teaching of which is hereto incorporated.
Preferably the device 1 comprises valve aspiration means suitable for permitting the passage of liquid from the aspiration duct 6 to the pressure chamber 4 when the piston 8 returns from the final position to the initial position and suitable to limit or prevent the return of the liquid from the pumping chamber 4 to the aspiration duct 6 when the piston moves from the initial position to the final position.
The valve aspiration means comprise an aspiration valve 30 suitable for fluidically separating the pumping chamber 4 from the aspiration duct 6, applied to the end wall 10b of the chamber 4, so as to surmount or cover the aspiration aperture 6a.
Preferably moreover, the device 1 comprises supply valve means suitable for allowing the passage of pressurised liquid from the pumping chamber 4 to the dispenser duct 14 when the piston moves from the initial position to the final position.
The supply valve means comprise a supply valve 60, applied to the intake of the dispensing duct 14, that is at the entrance aperture 14a.
The supply valve 60 comprises a membrane 62 which surmounts the entrance aperture 14a, having a front side 64, facing the dispensing duct 14, and a rear side 66. Preferably the membrane 62 is axial symmetric to a valve axis Y, for example coinciding with the dispensing axis Z.
In the rest configuration, the membrane 62, and in particular the front side 64, has a convex shape towards the dispensing duct 14.
According to one embodiment, the membrane 62, and in particular the front side 54, is a hemispherical shape.
The valve 60 further comprises, according to one embodiment, a continuous annular lip 68, projecting axially from the front side 66 of the membrane 62.
In the rest configuration, the annular lip 68 surrounds the entrance aperture 14a; for example, is placed so as to abut with the annular step 14c, preferably placing itself radially outside it.
Preferably moreover, the valve 60 comprises a stem 70, projecting from the rear side 66 of the membrane 62, preferably along the valve axis Y.
According to one embodiment, at the free end or distal end of the membrane 62, the stem 60 has an outer thickening which, preferably tapers towards the membrane 62, while on the opposite side it is connected to an annular draft 74.
According to a further embodiment, the stem 70 comprises a radial boss 70a towards the outside, for example annular and continuous.
Preferably the stem 70 is entirely axially hollow, preferably provided with a blind cavity towards the free end of the stem or towards the membrane 62.
Preferably moreover, the membrane 62 comprises an attachment portion 78 in the outer peripheral zone, which radially defines the membrane 62 externally and is for example defined between two side surfaces orthogonal to the valve axis Y.
According to a further embodiment, the attachment portion 78 comprises an annular cuff 78a which engages with the attachment wall 17, surrounding it externally.
The membrane is made in a relatively flexible membrane material.
The dispensing device 1 further comprises a blocking element 80, made in a more rigid material than the flexible material of the supply valve 60, suitable for blocking the supply valve 60 to the frame 3.
The blocking element 80 comprises a body 82, preferably comprising a plurality of angularly distanced reinforcement ribs 82a, and provided with a blocking hole 84, preferably axially through, in axis with the valve axis Y of the supply valve 60.
Preferably the body 82 comprises a blocking projection 86, projecting radially into the hole 84, fitted with a draft surface facing towards the dispensing duct 14.
The body 82 is suitable for snap-coupling to the supply valve 60, by means of the stem 70 snap-blockable to the projection 86.
Moreover, the blocking element 80 comprises an annular blocking wall 88, positioned peripherally externally to the body 82, having an axial extension.
The blocking wall 88 comprises an annular recess 90, preferably fitted with a draft surface, snap-engaged to the annular boss 17a of the frame 3.
This way the attachment portion 78 of the membrane 62 remains compressed between the body 82 of the blocking element 80 and the attachment wall 17 of the frame 3.
The membrane 62 has a lesser outer radial dimension than the inner radial dimension of the blocking wall 88, so as to prevent structural interference detrimental to the rapid assembly of the components. In other words, the membrane is radially peripherally distanced from the blocking wall 88.
Moreover, according to one embodiment, the blocking wall 80 comprises a stop collar 89, for example continuous and annular, projecting axially from the body 82, in axis with the hole 84.
According to a preferred embodiment, moreover, the device 1 comprises a cover 90 supported by the frame 3, to cover said frame and the inner components. The trigger 12 and preferably the nozzle 20 project from the cover 90.
According to a preferred embodiment, the aspiration valve and/or the supply valve are made by moulding, for example in one piece, for example in low density polyethylene (PELD) or in a plastic material, injected and expanded, closed cell grid, such as Ethylene-VinylAcetate (EVA) or Poly-Oxy-Ethylene (POE).
Preferably moreover, the blocking element is moulded, for example in a single piece, in a more rigid material than the membrane material, for example in polypropylene (PP).
Preferably moreover, the frame 3 element is moulded, for example in a single piece, in a more rigid material than the membrane material, for example in polypropylene (PP).
During normal use of the device 1, it is mechanically connected to the container and the tube is usually connected to the aspiration duct 6, to aspirate the liquid contained in the container.
In an initial configuration, let us assume that the pumping chamber 4 already contains the aspirated liquid and that the piston is in the initial rest position.
By operating the trigger 12, the piston 8 moves from the initial position towards the final position pushing the liquid contained in the pumping chamber 4, fulfilling a dispensing phase of use of the device.
During the dispensing phase, the liquid acts on the aspiration valve 30, so as to make a seal against the return of the liquid from the chamber 4 towards the container.
Moreover, during the dispensing phase, the liquid acts on the supply valve so as to distance the membrane 62 from the aspiration mouth 14a; in particular the liquid deforms the membrane 62 so that the annular lip 68 separates from the annular step 14c.
In particular, the liquid insinuates itself between the membrane 62 and the crown surface 18, externally to the annular lip 68, causing the detachment of said lip from the step 14c and thereby the entrance of the pressurised liquid into the dispensing duct 14.
During the deformation of the membrane the stem 70 performs a shift inside the hole 74, guided by the projection 86.
Advantageously, this permits a carefully guided and calibrated deformation of the membrane, preventing anomalous deformations.
The rearward movement of the membrane 62 is limited by the stop collar 89, against which it abuts during the dispensing phase.
During the dispensing phase, the elastic element is elastically deformed.
At the end of dispensing the piston is in the final position and the trigger is released. The return means act on the trigger to bring it back again, at the same time dragging the piston from the final position towards the initial position, performing a return phase of use of the device.
During the return phase, a depression is created in the pumping chamber 4 by means of the sealingly sliding of the piston 8.
During the return phase, the aspiration valve 30 make it possible to aspirate liquid from the container into the pumping chamber 4.
In the return phase moreover the membrane 62 of the dispensing valve 60 remains in contact with the step 14c or with the bevel 14d of the frame 3.
Innovatively, the dispensing device according to the invention behaves in an optimal manner when dispensing, thanks to the optimal seal between the valve and the frame.
Advantageously, moreover, the device is very simple to assemble and therefore makes it possible to reduce machine-time and therefore increase production
In particular, many components are coaxial, permitting a very rapid assembly; moreover many components are axial-symmetric, thereby preventing problems of orientation for assembly.
According to a further advantageous aspect, the components are often snap connected, leading to high speed and reliable assembly.
It is clear that a person skilled in the art may make modifications to the device described above so as to satisfy contingent requirements.
For example, according to one embodiment, the piston axis and the dispensing axis are separate and incident.
Such variations are also included within the sphere of protection as defined by the following claims.

Claims

Trigger dispensing device (1) for a liquid comprising:
- a pumping chamber (4) and a piston (8) sealingly sliding in the pumping chamber (4) along a piston axis (X);

- a trigger (12) operatively connected to the piston (8) to move it;

- an aspiration duct (6) fluidically connectable to a container of the liquid to be dispensed, wherein said aspiration duct (6) comes out in the pumping chamber (4) through an aspiration aperture (6a);

- a dispensing duct (14), made in a frame (3) in rigid material, extending along a dispensing axis (Z), in fluidic connection at one end with the pumping chamber (4) through an entrance aperture (14a) and, at the other end, in fluidic connection with the outside environment wherein the entrance aperture (14a) is surrounded by an axial boss (14c) in rigid material;

- an aspiration valve (30) suitable to regulate the passage of fluid between the aspiration duct (6) and the pumping chamber (4);

- a supply valve (60) suitable to regulate the passage of fluids between the pumping chamber (4) and the dispensing duct (14) comprising a membrane (62) in flexible material, abutting, in the rest configuration, with the axial boss (14c) of the dispenser mouth (14a);

- a blocking element (80), made in a rigid material, suitable to engage with the frame (3) and to influence said membrane (62) in compression to hold it tight against said frame (3), and comprising a hole (84) in which the delivery valve engages (60);
characterised in that the supply valve (60) comprises a stem (70) sliding in the hole (84) of the blocking element (80).
Device according to claim 1, wherein the blocking element (80) can be snap-coupled to the frame (3).
Device according to claim 1 or 2, wherein the blocking element (80) comprises a blocking wall (88) snap-couplable to the frame (3) and the membrane (62) is peripherally radially distanced from the blocking wall (88).
Device according to any of the previous claims, wherein the stem (70) is snap-couplable to an annular protuberance (86) in the hole (84) of the blocking element (80).
Device according to any of the previous claims, wherein the stem (70) is internally at least partially hollow.
Device according to any of the previous claims, wherein the membrane (62) comprises an annular lip (68) projecting axially, abutting with the intake of the entrance aperture (14a).
Device according to any of the previous claims, wherein the axial boss (14c) is an annular step.
Device according to any of the previous claims, wherein the front side (64) of the membrane (62) is convex towards the dispenser mouth (14a).
Device according to any of the previous claims, wherein the membrane (62) comprises an attachment portion (78) positioned peripherally, defined between two axially distanced surfaces, orthogonal to the dispensing axis(Z).
Device according to any of the previous claims, wherein the blocking element (80) comprises an axially projecting annular collar (89) suitable to act as a stop to the membrane (62) in deformation.
Device according to any of the previous claims, wherein the piston axis (X) is parallel and separate from the dispenser axis (Z).
Device according to any of the previous claims, wherein the membrane (62) comprises an attachment portion (78) positioned peripherally, fitted with a cuff (78a) for engagement with an attachment wall (17) of a frame (3) of the device.
Device according to any of the previous claims, wherein the front side (64) of the membrane (62) is convex towards the dispenser mouth (14a).
Device according to claim 13, wherein the membrane (62) has a front surface (64) of a hemispherical shape.