"A TRIGGER-TYPE DISPENSING HEAD FOR A DISPENSING DEVICE FOR PASTY PRODUCTS SUCH AS TOOTHPASTES"

[0001]The subject of the present invention is a dispensing head assembly for a push-button dispenser for pasty products, in particular toothpastes. Moreover, also part of the invention is said dispenser for pasty products. [0002]Such dispensers have been known for some time, and the Applicant itself holds the patent family coming under document US 4,821,926. Such dispensers have been and continue to be widely known for certain advantages that set them apart from normal toothpaste tubes, such as, for example, ease of use, the ability to dispense practically all of the toothpaste without any remaining, and other advantages.

[0003]There are essentially two types of these dispensers on the market.

[0004]A first type, used especially for high-viscosity pastes, provides a metal stop ring on the bottom of the tube which, when the push-button is released (suction step), advances together with the piston toward the top of the tube and, when the push-button is pressed (dispensing step), prevents the piston from recoiling toward the bottom of the tube. An example embodiment is described in document US4154371. [0005]A second type, used especially for medium- or low- viscosity pastes, instead comprises parts having lips or diaphragms that work as check valves, and therefore the piston does not have to cooperate with a stop ring. An example embodiment is described in document US4402431.

[0006]This latter type is quickly becoming widespread because it is possible to make all the components out of plastics materials belonging to the same family. As such, these dispensers are easily recyclable and meet current environmental protection requirements. The Applicant is the holder of Italian patent applications No. 102020 000 025 597, 102020 000 025 594 and 102021 000 007 847, for example.

[0007]Further examples of push-button dispensers are described in the documents US4807784, EP0277893 and EP0599301, in which the dispensing head comprises breakable bridges configured to remain attached to the actuator, following the first dispensing. However, in these solutions, the dispensing head is made in a single piece with the container tube or its tubular components, known as lids or skirts, leading to a significant increase in structural complexity, and are thus disadvantageous to manufacture. In addition, breakable bridges may break in an uncontrolled manner and be dispersed into the surrounding area, resulting in environmental pollution.

[0008]The object of the present invention is to make a dispenser for pasty products, in particular toothpastes, that meets the requirements of the sector, in particular with regard to the use of plastics materials and the complete recyclability of the dispensers, and allows for effective dispensing of the product.

[0009]This object is achieved by a head assembly for a dispenser according to claim 1 and by a dispenser according to claim 16. The dependent claims describe additional advantageous embodiments.

[0010]The features and advantages of the dispenser according to the present invention will become apparent from the following description, given as a non-limiting example in accordance with the figures in the appended drawings, wherein:

- Figure 1 depicts a dispenser for pasty products according to an embodiment of the present invention;

- Figure 2 is a sectional view of the dispenser in Figure 1;

- Figure 3 is a sectional view of a head assembly of the dispenser according to one embodiment of the invention, in an initial configuration;

- Figure 4 shows an enlargement of Figure 3, in which the guarantee tab is highlighted; - Figure 5a shows a fixed head of the head assembly, according to an embodiment of the invention, in the initial configuration;

- Figure 5b is a bottom view of the fixed head shown in Figure 5a;

- Figure 6 is a sectional view of the head assembly in a dispensing configuration of the product.

[0011]With reference to the figures in the appended drawings, reference sign 1 refers collectively to a dispenser for pasty products, in particular toothpastes, according to an embodiment of the present invention.

[0012]The dispenser 1 comprises a container tube 2, preferably made as one piece from plastics material, for example a polymer material belonging to the polyolefin group, such as polypropylene (PP).

[0013]The container tube 2 comprises an annular, typically circular cylindrical tube wall 4 having a central axis Z. The tube wall 4 peripherally delimits a tube compartment 6, intended to contain the pasty product. The tube wall 4 goes from a lower end 8, which is itself open and through which the tube wall 4 is filled with the pasty product, to an upper end 10 to which a dispensing head 50, to be discussed later, is applied.

[0014]The dispenser 1 further comprises a piston 12 received in the tube compartment 6 by an interference fit, designed to slide axially from the lower end 8, where it is located when the tube compartment 6 is full of product, to the upper end 10 as the product is dispensed. [0015]Preferably, the piston 12 is made of a plastics material, preferably a polymer material belonging to the polyolefin group, for example high-density polyethylene (HDPE).

[0016]The dispensing head 50 comprises a main chamber 20 placed at the upper end 10 of the container tube 2 and suitable for containing the product that is about to be dispensed.

[0017]The dispensing head 50 comprises a pumping unit 28 that comprises an elastically deformable cap 26. [0018]According to a preferred embodiment, the main chamber 20 is delimited at the bottom by a separating wall 24, occupying the tube compartment 6 in the diametrical direction, and at the top by the cap 26 of the pumping unit 28. The separating wall 24 is provided with a suction opening 24a suitable for establishing communication between the tube compartment 6 and the main chamber 20. Preferably, the suction opening 24a sits on an imaginary plane K perpendicular to the main axis X. [0019]According to an embodiment of the invention, the separating wall 24 is a single piece together with the container tube 2.

[0020]Preferably, the separating wall 24 comprises an annular functional seat 34, to receive a support for a valve body, which will be discussed later herein, and a support crown 35, placed radially inside the functional seat 34, to support said valve body.

[0021]The dispensing head 50 comprises a fixed head 40 which may be applied to the container tube 2 at the upper end 10. For example, the fixed head 40 is snapped into an end segment 22 of the tube wall 4.

[0022]The fixed head 40 comprises a dispensing duct 42 suitable for connecting the main chamber 20 to the external environment for dispensing the product.

[0023]Preferably, the dispensing duct 42 comprises an initial segment 44 that opens directly into the main chamber 20, and an end segment 46 connected to the initial segment 44 and ending with an opening 47 for dispensing the product, positioned in a front region of the dispensing head 50. [0024]Preferably, the initial segment 44 lies along a main axis X, preferably coaxial to the tube wall 4, i.e., coincident with the central axis Z; the end segment 46, however, is preferably inclined and therefore lies along a dispensing axis Y that is inclined with respect to the central axis Z. [0025]Having applied the fixed head 40 to the container tube 2, an operating region 43 is delimited between said fixed head 40 and the separating wall 24, in which operating region the dispensing duct 42 and the pumping unit 28, which is applied and cooperates with the separating wall 24, are arranged.

[0026]The pumping unit 28, comprised of a hollow shell, is made as one piece from plastics material, for example a polymer material belonging to the polyolefin group, such as low-density polyethylene (LDPE).

[0027]The pumping unit 28 comprises an elastically deformable, dome-shaped cap 26. Said cap 26 is suitable for being deformed with respect to a rest condition in order to reduce the volume of the main chamber 20 and cause the product to be dispensed.

[0028]The pumping unit 28 further comprises a pump neck 55 connected to the cap 26 and protruding axially therefrom. The pump neck 55 is slidably inserted onto the initial segment 44 of the dispensing duct 42. [0029]For example, the pump neck 55 is comprised of a tubular column portion 56, preferably coaxial with the central axis Z, and a tubular guide portion 58 connected to the column portion 56 and contained radially and preferably also axially therein. In other words, the guide portion 58 forms a flap with respect to the column portion 56, thus making therewith an annular inverted "U"-shaped section.

[0030]The dispensing head 50 further comprises an intermediate valve or shutoff valve suitable for allowing product to pass from the main chamber 20 to the dispensing duct 42 during a product dispensing step, and preventing product from coming out of the main chamber 20 and going to the dispensing duct 42 when the container tube is being filled with the product. [0031]For example, the pumping unit 28 comprises a bottom 60 supported by the pump neck 55 and in particular by the guide portion 58; the bottom 60 is provided with a plurality of bottom openings 62 arranged circumferentially. Once the pumping unit 28 and the fixed head 40 are applied to the container tube 2, the initial segment 44 of the dispensing duct 42 is inside the guide portion 58 and, in an initial rest condition, the appropriately shaped, free lower end 44b of said initial segment 44 closes said bottom openings 62 of the bottom 60. The free end 44b and the bottom 60 provided with bottom openings 62 form an example of said intermediate valve 64 or shutoff valve.

[0032]The dispensing head 50 further comprises an upper valve or delivery valve 72, placed downstream of the intermediate valve, suitable for allowing the product to pass from the main chamber 20 to the external environment during a product dispensing step, and for preventing the return of product or air from the external environment into the main chamber 20 during a product suction step. [0033]For example, a delivery port 66 is placed at the connection between the initial segment 44 and the end segment 46 of the dispensing duct 42, with a cup 67 housed in the end segment 46 cooperating therewith, said cup 67 being comprised of an annular cup wall 69 and a flexible cup flap 71 suitable for closing the delivery port 66, acting as a shutter. The delivery port 66 and the cup flap 71 constitute an example of said upper valve or delivery valve 72.

[0034]The dispensing head 50 further comprises a lower valve or suction valve 76 suitable for allowing product to pass from the tube compartment 6 to the main chamber 20 during a product suction step, and for preventing the return of the product from the main chamber 20 to the tube compartment 6 during a product dispensing step.

[0035]To that end, the dispensing head 50 comprises a valve body 74 that cooperates with the suction opening 24a.

[0036]Preferably, the valve body 74 comprises a support 78 comprised, for example, of an annular wall, received at least partially in the functional seat 34 of the separating wall 24, and a tab 77 comprised radially in the support 78 which, by cooperating with the separating wall 24, is suitable for closing off the suction opening 24a.

[0037]Preferably, moreover, the valve body 74 comprises a plurality of elastically deformable hinge portions 79 which connect the tab 77 to the support 78 and, by deforming, allow said tab 77 to move from a closed configuration of the suction opening 24a assumed during the product suction step to an open configuration of the suction opening 24a assumed during the product dispensing step.

[0038]In particular, by means of said hinge portions 79, for example three in number, the tab 77 is arranged in a cantilevered fashion inside the support 78, i.e., spaced from said support 78 so as to form an annular gap 78a therewith, except at said hinge portions 79.

[0039]Preferably, the tab 77 rests on the support crown 35 in the closed configuration of the suction opening 24a.

[0040]According to a variant embodiment, the tab 77 is comprised of a single planar body, e.g., circular in shape, e.g., made in one piece with the support 78, which rests perimeterwise on the support crown 35. [0041]The dispensing head 50 further comprises an actuator 80, for example in the form of a button, held at the back so as to be movable such as by rotation or translation from the fixed head 40, and suitable for influencing the pumping unit 28 so as to cause the deformation of the cap 26 and the dispensing of the product. For example, the actuator 80 comprises an influence portion 82 in contact with the connection area between the column portion 56 and the guide portion 58, such that the squeezing thereof causes deformation of the cap 26.

[0042]Preferably, during the product dispensing step, the actuator 80 makes a roto-translatory motion toward the rear region of the dispensing head 50 and axially toward the separating wall 24. [0043]Preferably, the actuator 80 also comprises a closing portion 84 suitable for closing, in a rest configuration of the dispenser, the opening 47 of the dispensing duct 42.

[0044]The actuator 80 is made as a single piece from plastics material, for example a polymer material chosen from the polyolefin group, such as polypropylene (PP). [0045]The dispensing head 50 comprises a guarantee tab 70, made in one piece with the actuator 80, engaged mechanically to the fixed head 40, e.g., glued or by means of a shape or force coupling. The guarantee tab 70 comprises a tab body 73 and at least one bridge 75, e.g., three bridges 75, that connects the tab body 73 to the actuator 80, preferably to one of its external actuator surfaces 81. In particular, the at least one bridge 75 is configured to break on the first operation of the actuator 80; further, the tab body 73 is configured to remain engaged mechanically to the fixed head 40 following the first operation of the actuator 80.

[0046]In other words, the actuator 80 is a separate component from the fixed head 40. In particular, the actuator 80 is at least partially supported by the fixed head 40. By means of the guarantee tab 70, the actuator 80 is connected to the fixed head 40.

[0047]In still other words, the guarantee tab 70 is a distinct component from the fixed head 40.

[0048]Preferably, the fixed head 40 comprises an annular wall 41, positioned at the back, ending axially with an upper edge 415 to which the tab body 73 is engaged. For example, the tab body 73 comprises a coupling portion 735, projecting radially outward, snap-engaged to said upper edge 415.

[0049]For this purpose, the upper edge 415, having an inner annular surface 410, comprises a coupling tooth 416 projecting radially from said inner annular surface 410 configured to be snap-engaged by the coupling portion 735.

[0050]Preferably, the tab body 73 comprises an outer wall 731 and an inner wall 733 spaced radially, and an upper wall 732 joining them, forming an inverted "U"- shaped section, on an imaginary plane containing the main axis X.

[0051]Specifically, the guarantee tab 70 has a continuous planar joining surface 737, i.e., without depressions or protrusions, that joins the at least one bridge 75 with said upper wall 732 at the top. In other words, the at least one bridge 75 and the upper wall 732 are axially aligned and radially contiguous, making the state of the at least one bridge 75 better visible.

[0052]In still other words, the inner wall 733 is radially spaced from the outer actuator surface 81 of the actuator 80.

[0053]Preferably, the inner wall 733 is provided with the coupling portion 735 at its lower axial end.

[0054]In a preferred embodiment, the outer wall 731 extends for a greater axial length with respect to the axial length of the inner wall 733, e.g., it extends axially beyond the coupling portion 735, making the guarantee tab 70 particularly rigid and resistant to impact or any attempts at removal. [0055]In a preferred embodiment, the bridge 75 comprises, preferably arranged in a radial direction: an attachment portion 751 connected to the tab body 73, a breakable portion 752 configured to separate from the attachment portion 751 at the first operation of the actuator 80, and a resistant portion 753 connected between the breakable portion 752 and the actuator 80. Preferably, the resistant portion 753 has a trapezoidal section on an imaginary plane containing the main axis X.

[0056]In other words, following the first operation of the actuator 80, the attachment portion 751 and the breakable portion 752 are connected to the actuator 80, while the resistant portion 753 is connected to the tab body 73 (Figure 6).

[0057]The actuator 80 comprises an annular wall 86 which integrally engages the fixed head 40 and has a sliding portion 87 positioned at the rear and radially lowered inwardly with respect to the annular wall 86, suitable to slide axially freely with respect to the guarantee tab 70, and in particular with respect to the inner wall 733. Preferably, moreover, with the bridge 75 intact, the at least one bridge 75 is connected to said sliding portion 87.

[0058]In a preferred embodiment, moreover, the inner wall 733 is positioned radially at the same radial distance as the annular wall 86, relative to the main axis X. In other words, the inner wall 733 is radially positioned on the imaginary circumference over which the annular wall 86 extends, as seen, for example, in

Figure 5b. Preferably, by doing so the dispensing head 50 is compact overall, so that it does not protrude radially from the profile of the tube wall 4.

[0059]In a preferred embodiment, the sliding portion 87, in an imaginary plane containing the main axis X, has an "S"-shaped section comprising an upper region 89 that is outwardly concave, and a lower region 88 that is outwardly convex and connected to at least one bridge 75. In other words, the lower region 88 of the sliding portion 87 provides the external actuator surface 81.

[0060]The sliding portion 87 has a circumferential extension at least equal to the inner wall 733 and is thus shaped to move relative to the guarantee tab 70, resolving the risk of interfering with it by removing it from the fixed head 40.

[0061]Regarding the operation of the dispensing head 50, in its initial or resting configuration (Figure 3), the pumping unit 28 is in an initial non-deformed condition, the cup flap 71 blocks the delivery port 66 (delivery valve closed), the tab 77 is in sealed contact with the support crown 35 (suction valve closed) and the bottom 60 is engaged with the lower end of the initial segment 44 so that the bottom openings 62 are blocked (shutoff valve closed). Moreover, the closing portion 84 of the actuator 80 blocks the opening 47 of the dispensing duct 42. [0062]A dispensing step (Figure 6) takes place with the operation of the actuator 80 by the gradual deformation of the pumping unit 28 and in particular the cap 26.

[0063]When the actuator 80 is operated, in effect, the closing portion 84 is disengaged at least partially from the opening 47, leaving it free to dispense the product. [0064]During the dispensing step, the cap 26 of the pumping unit 28 is deformed, guided along the main axis X along which the guide portion 58 translates. A resulting reduction of the volume of the main chamber 20 occurs, while the overpressure caused by the squeezed product keeps the suction valve 76 in the closed configuration. In other words, the tab 77 is pushed into sealed contact with the support crown 35, thus closing the suction opening 24a. This prevents the product contained in the main chamber 20 from returning to the tube compartment 6 of the tube 2.

[0065]At the same time, due to the thrust practiced by the actuator 80, the column portion 56 lowers, preferably guided in this movement by the guide portion 58, which slides as it is guided into contact with the dispensing duct 42 and in particular with the initial segment 44 thereof.

[0066]The lowering of the column portion 56 causes the bottom 60 to lower and disengage from the initial segment 44 of the dispensing duct 42; in particular, the lower end of the initial segment 44 emerges through the bottom openings 62. The shutoff valve 64 thus changes to the open configuration and the product contained in the main chamber 20 comes through the bottom openings 62 in the bottom 60.

[0067]At the same time, due to the action of the product which is now located between the bottom 60 and the initial segment 44 of the dispensing duct 42, the cup flap 71 moves away from the delivery port 66. The delivery valve 72 thus changes to the open configuration and the product may come out through the opening 47 of the dispensing duct 42.

[0068]When the actuator 80 reaches the end of travel, the dispensing step ends and, after the actuator 80 is released, a suction step occurs, during which time a predefined quantity of product contained in the tube compartment 6 enters the main chamber 20.

[0069]In particular, when the actuator 80 is released, the pumping unit 28 tends to return to the non-deformed condition and influences the actuator 80 in that direction, which tends to return to the initial condition. Therefore, the volume of the main chamber 20 tends to increase and the resulting partial vacuum causes the tab 77 to bend, disengaging from the support crown 35. A predefined quantity of product contained in the tube compartment 6 is thus drawn into the main chamber 20.

[0070]At the same time, the cup flap 71 recloses the delivery port 66 such that the delivery valve 72 returns to the closed configuration. This ensures that the product in the dispensing duct 42 between the delivery valve 72 and the opening 47 does not return to the main chamber 20, nullifying the suction of new product from the tube compartment 6. [0071]At the same time, the closing portion 84 of the actuator 80 tends to return to the initial condition in which the opening 47 is blocked, thereby cutting off the flow of dispensed product and facilitating separation of the dispensed quantity. [0072]Once the cap 26 has returned to the non-deformed condition, the bottom 60 also returns to the initial position in which it engages with the initial portion 44; the shutoff valve 64 thus returns to the closed configuration and, since the overpressure in the main chamber has ceased, the suction valve 76 also returns to the closed configuration.

[0073]Innovatively, the dispensing head and the dispenser comprising it according to the present invention are particularly suitable to dispense pasty products, presenting a particularly effective suction step.

Advantageously, moreover, the tab body is also configured to remain firmly connected to the dispensing head during the life cycle of the dispenser, resolving the risk of its dispersion into the environment, favoring the total recyclability of the dispenser.

[0074]Advantageously, the guarantee tab is configured to highlight tampering of the dispenser, such as a previous operation of the actuator. Advantageously, the tab body remains mechanically engaged to the fixed head, demonstrating at first glance and in a clear way an actuation occurred, resolving the need to inspect the condition of the guarantee tab.

[0075]It is clear that a person skilled in the art, in order to satisfy current needs, could make modifications to the dispenser described above, all being contained within the scope of protection as defined in the following claims.

[0076]For example, according to a variant embodiment not shown in the attached figures the tab body is circumferentially discontinuous, i.e., it comprises a plurality of angularly spaced half-bodies, preferably each comprising at least one bridge.

[0077]For example, according to a further variant embodiment, the tab body is either glued or heat-sealed to the fixed head.