The invention relates to a dispensing device for dispensing liquids from flexible packaging, in particular for dispensing defined amount of liquid from a flexible packaging in the form of pouches or bags of plastic material, in particular "pouch" type packaging.

Many liquids, used for example in households or at vehicles servicing or other devices for everyday use are currently available on the market in a "pouch" type flexible packaging, also known under the names "doypack" or "cheerpack" . Such packaging is regarded in general as refill packaging which implies necessity of cumbersome transferring and pouring out liquid from them to a final packaging or using a special dispenser of a handled device.

There are known devices designed to facilitate dispensing liquid from this type of flexible packaging, in particular in the form of a dispenser that can be combined or attached directly to packaging having a suitable spout, for example as described in U.S. Patent No. 7,850,044B2. The spout according to this embodiment is connected to a flexible container, for example made of a plastic film, and has a certain number of boat-shaped welded flat fin-like ribs around a central neck portion, spaced apart and parallel to each other to stabilize the container during exerting pressure on the container. Tabs projected outwardly are located in the middle fin-like ribs area .

However, most currently used dispensing method is a dispensing measuring container attached to flexible packaging and calibrated with volume defining lines marked on a side wall. It is often a screw cap of a larger container containing liquid to be dispensed. In the case of a "doypack" type flexible packaging this kind of a cap screw cannot be used and therefore companies that produce liquids offer these measuring containers free of charge in a shop (Migros, Switzerland) or deliver them upon request (as for example Werner & Mertz company, the manufacturer of products under the name Frosch) , which is associated with some nuisance. DRY Inc. (US) markets ProWash detergent packed in the doypack type packaging provided with adhered measuring element. Additionally, in case of large containers containing 1, 2 or even 4 litres of liquid to be dispensed filling its appropriate amount by watching not to exceed the specific line put on the dispensing container is not easy task, especially for older, weaker persons or ones having poor eyesight.

There are also known other solutions of dispensers adapted to dispense liquid from packaging, for example the solution from Taplast described in Patent No. US 6,672,486B2 in the form of a pump dispenser, which is mounted on an opening of a liquid container by a screw-on plug, in which the dispenser body is mounted defining a suction and a discharge chamber being in fluid communication to a channel for suction a liquid from a container and to a dispensing channel. Valve means to regulate liquid inflow and outflow are provided upstream of the suction channel and downstream of the dispensing channel. A working element is a piston arranged movably, slidable inside a hollow body and cooperating with a flexible bellows element, wherein the bellows element is arranged between the piston and the body and acts as a spring actuating an automatic return movement of the piston, wherein said bellows element has a shape of cylinder or cone and is provided with circumferential ribs arranged on the outer circumference thereof. Said dispenser comprises elements limiting movement of the piston in the form of vertical grooves of different length arranged on the plug and cooperating projections on the piston for setting a dispensing volume of a liquid in three predetermined positions. Accordingly, this type of a pump dispenser is able to dispense only predefined volumes of a liquid. This is achieved by different lengths of the grooves (recesses) whereby movement of said piston of the pump takes place along a defined and predetermined way, that results in dispensing a precise volume of a liquid. The disadvantage of that solution is inability to identify by the user himself of any dispensed volume of a liquid to be dispensed, since it is only possible to select one of the volumes provided by a manufacturer. Additionally, such dispensing pump is not suitable for applications used for emptying flexible packaging the structure of which is not sufficiently rigid.

It is known a solution from Meadwestvaco Calmar Netherlands BV designed for dispensing liquids from a "pouch" type flexible packaging described in the publication O2013/074932 in the form of a resilient bellows-actuated pump, fixed to this type packaging. The said device allows dispensing liquid from such packaging, however, there is no possibility to adjust a volume of a liquid to be dispensed. The device is a resilient bellows-actuated dosing pump connected to a flexible packaging of a plastic film by means of a special fastening tool, tightly connected to said packaging and adapted to be connected to a base of a pump body. A resilient bellows is attached to a base of a pump body by a lid and has an upper domed part which is resiliently deformable and side walls defining an inner chamber of said bellows that is in fluid communication to said inner chamber of the base of the pump body which together form the chamber of said pump. Said base of the pump body has at least one inlet channel being in fluid communication with an interior of a flexible packaging and with internal chamber in said pump base while said internal chamber of the pump base has at least one outlet being in fluid communication with an outlet channel of said pump. In a bottom of the pump base a spacer can be positioned, which is used for defining said volume of said internal chamber of the base and further to determine in cooperation with suitably shaped flexible dome of said resilient bellows the volume of said chamber of the pump, and thus the volume of liquid dispensed through the pump.

A connection of the chamber of the pump to the inlet channel and the outlet of the chamber of said pump can be closed and opened by means of flexible side walls of both the bellows and the base of the pump body, or in an alternative embodiment by using one of said ribs of the resilient bellows and cooperating with it rib, belonging to the base of the pump body. That connection to the outlet channel is opened through pressure exerted by a user to the bellows dome and it's deformation which results in opening of the pump chamber outlet and pushing out a liquid volume contained in said chamber. After releasing pressure the bellows dome returns to its original shape, which in turn creates a negative pressure in the chamber of the pump, sufficient for opening connection to the inlet channel of the chamber and sucking in the liquid from the packaging into the pump chamber again. In another embodiment, dosing pump is additionally provided with a valve stem functioning as a valve member moving slideably in the pump chamber and terminated at the inlet channel side with a flexible disk valve for closing and opening connection between the inlet channel and the pump chamber, during exerting and releasing pressure on the bellows dome, respectively. On the other hand, said valve stem is adapted to closing and opening the outlet of the pump chamber, during releasing and exerting pressure on the bellows dome, respectively.

The above-described dispensing device with a flexible bellows as an actuator for starting pumping a liquid has not a structure allowing freely changing a volume of a liquid to be dispensed, i.e. a selected by a user dispensed volume value. During pressing the bellows dome a similar volume of a liquid resulting from the volume of the pump chamber is always dispensed.

Known is also an equipment for dispensing liquids from flexible packaging according to US 2007/0114247, which discloses a device of the type of a manual pump actuated by a resilient bellows, wherein pressing said bellows results in closing an inlet of a liquid from the packaging into a dosing space of said pump and at the same time said liquid outflow, i.e. dosing a predetermined volume of a liquid from said dosing space through an open outlet of the pump. Releasing a pressure will result in sucking in said liquid from the packaging into said dosing space of the pump.

An additional difficulty during dispensing liquids from a flexible packaging is that different companies use different diameters of threads on the outlet nozzles of packaging, making it difficult to manufacture a dispenser matching to said various types of threaded fittings.

Devices known from the above patents for dispensing liquids from flexible packaging are poorly adapted to cooperate with a flexible packaging, which tends to deform during exerting pressure, even a small pressure on them, for example during pressing a flexible bellows to start dispensing a liquid, a difficult operation of said device is caused which does not ensure complete emptying a liquid from said packaging.

In order to overcome the above mentioned drawbacks of the dispensers known in the art when used for emptying of flexible packaging it has been proposed a dispensing device according to the invention with the characteristics described below.

Short description of the invention

A dispensing device according to the present invention for dispensing liquids from flexible packaging, in particular for dispensing a defined amount of a liquid from a flexible packaging comprises a device body having generally elongated shape, wherein in said body at its one end, an inlet fitting with an inlet opening is mounted, and at its another end an outlet fitting with an outlet opening is mounted. Said inlet fitting and outlet fittings, preferably, are arranged opposite each other. Wherein the body defines an inner space of the body, preferably in the form of an internal central opening and said body is further provided on its side surface with a connection opening being in fluid communication with said central opening. Further, a resilient bellows is attached in a sealed manner with its open end side to said connection opening, and preferably to a flange outwardly projecting from a side surface of the body and surrounding said connecting opening. Said resilient bellows has generally cylindrical shape and consists of a certain number of folds, preferably in the form of helical coils, that folds are positioned along longitudinal extension of said bellows and wherein said resilient bellows defines inside an inner space of said bellows, which inner space is in fluid communication with said connection opening of the body. An opposite end of said resilient bellows being closed with a bottom, and wherein said folds or helical coils of resilient bellows are adapted to flex under pressure exerted on said bottom in axial direction of said bellows, towards the body.

Said dispensing device is further provided with an assembly for stepless adjustment of a volume of dispensed liquid by means of: stepless setting up a volume of said inner space of said resilient bellows and/or stepless setting up a number of free folds and/or helical coils of said resilient bellows which can flex under pressure, wherein said stepless setting can be performed for each, individual action of dispensing of a liquid, and wherein said assembly for stepless adjustment comprises a control element cooperating with said resilient bellows and arranged on outer side surface of said bellows and/or said flange, around their outer periphery, at least on a certain section of a length of said resilient bellows and/or said flange. Further, said control element is provided with marks indicating an adjustable volume of a liquid to be dispensed.

Said control element can be shaped in the form of an adjusting nut disposed around outer peripheral surface of said resilient bellows, and particularly around outer surface of said helical coils or folds of the bellows.

Said adjusting nut in preferred embodiment is provided with an internal thread, adapted in size to dimensions of helical coils of the bellows (9) for stepless continuous adjustment of a volume of said inner space of the resilient bellows by setting out an appropriate, available number of free coils of said bellows. In embodiment of the invention said adjusting nut is mounted without any possibility of longitudinal displacement relative to outer surface of said resilient bellows and relative to said body, but with possibility for rotation relative to said surface of said resilient bellows about longitudinal axis of said bellows, which axis coincides with the axis of said adjusting nut, and further wherein said internal thread defines a thread projection.

In alternative embodiment of the invention said control element of said assembly for stepless adjustment of a volume is shaped in the form of an adjusting nut disposed around an outer peripheral surface of said flange and/or said resilient bellows, in particular around a certain portion of said outer surface of bellows folds and/or bellows helical coils, which adjusting nut is provided with an internal thread in the form of a guide groove cooperating with a projection located on said flange, which is matching in shape and adapted in size to said internal thread for stepless adjustment of a dosing volume by setting out an appropriate, available number of free folds or helical coils of said resilient bellows and having possibility of flexing under axial pressure exerted on said bottom towards said body, and wherein said adjusting nut is mounted with possibility of longitudinal displacement relative to said outer surface of said resilient bellows and relative to said body and simultaneously with possibility for rotation relative to said surface of said resilient bellows about the longitudinal axis of said bellows, which axis coincides with the axis of said adjusting nut.

Both said internal threads of said adjusting nut comprise only one thread turn, preferably one incomplete thread turn extending about less than full 360° circumference.

The dispensing device according to further embodiment of the invention has said inlet fitting and outlet fitting provided with catch elements extending in the direction of the axis of said connection opening, from their respective bottom surfaces facing that side of the body, on which said connection opening is arranged, surrounded with said flange fixedly attached to the body. Said catch elements can be so shaped as to be located at a distance from both, a side surface of the body facing towards them and a surface of said flange, so that a receiving space is defined. Preferably, said catch elements are formed for arresting axial sliding displacement of said adjusting nut relative to the body.

In further embodiment an adjustment space can be formed between a front surface of said outer flange of the body and said thread projection of said internal thread of said adjusting nut for accommodating a portion of said helical coils number, forming said folds of said resilient bellows during rotation of said adjusting nut.

Further, valve elements, preferably in the form of inlet valve and outlet valve can be provided in said connecting opening of the body.

In further one embodiment of the invention a recess is formed in a side surface wall of the body, opposite to said connection opening, said recess is formed having walls inclined at an angle and converging towards inside, for example forming a V-shape in cross-section. Said walls of said recess divide said inner space of the body into two separate sections constituting two adjacent partial openings, one of which is connected to the inlet fitting and is in fluid communication with its inlet opening on the one hand, and on the other hand it is connected through said valve element located in a part of said connecting opening to said inner space of the resilient bellows, while the second of which partial openings is in fluid communication with discharging opening of said discharging fitting on the one hand, and on the other hand through said outlet valve with said inner space of the resilient bellows.

Outer surface of said control element, preferably in the form of said adjusting nut is provided with a suitable scale indicating a volume to be set and dosed in specified units, preferably in millilitres (ml) , wherein in addition an auxiliary marks are preferably applied to individual folds or coils of said resilient bellows. Additional indications can be also applied on outer surface of said resilient bellows or said flange.

According to the invention another embodiment the resilient bellows is a bellows formed as a body of revolution, preferably with a cylindrical contour and a constant diameter and having lateral outer surface in the form of folds formed, preferably, in the shape of helical coils and/or alternatively circular folds.

Said adjusting nut can be provided with an internal thread or demonstrates self-locking with respect to rotational movement relative to said resilient bellows and/or said flange, and particularly relative to said bellows folds and/or coils, which self-locking is obtained by means of selection of appropriate materials for both said cooperating elements, or by means of shape- and dimensional coupling of those elements. A dispensing device according to the present invention solves the problem to ensure dispensing of any user-selected volume of a liquid from a flexible packaging that can be freely selected by a user, and allows an adjustment of any desirable liquid volume or its mass to be dispensed, which volume or mass can be set freely and immediately before said dispensing operation by a user himself, wherein an amount of a volume to be dispensed can be adjusted substantially smoothly, that means stepless.

The device according to the invention is particularly suitable for cooperation with a flexible packaging having low shape stability and having a wide variety of their sizes and shapes, which allows device complete emptying of a liquid from said packaging while simultaneously preventing liquid dripping from a dispenser after dispensing is finished. It can be moreover readily adapted to different outlets, including outlet ports or outlet nozzles of flexible packaging or bags.

Description of drawings

In the accompanying drawings preferred embodiments of the dispensing device according to the invention are presented, which are for illustrative purpose only and which do not limit a scope of the invention. The figures of the drawings show, respectively:

Figs, la and lb - the dispensing device according to the invention in its dispensing position connected to a packaging placed in a holder or on a suitable catch, schematically;

Fig. lc - perspective view of an embodiment of the inventive dispensing device;

Figs. 2a-2c - the dispensing device in the first embodiment according to the invention, in different working positions, in axial section;

Fig. 3 - front view of a control element in the form of an adjusting nut according to the invention; Fig. 4 - schematic view of valves located in a connection opening according to the second embodiment of the invention as seen from a device body side;

Figs. 5a-5d - the dispensing device in the second embodiment according to the invention in different working positions, in axial section;

Figs. 6a-6c - the dispensing device in the third embodiment according to the invention in different working positions, in axial section.

Description of preferred embodiments

To ensure optimum emptying of a flexible packaging it is proposed according to the invention that said packaging is disposed in such a manner that its spout, i.e. its pouring opening, is directed downwardly, so that a liquid may freely outflow from the packaging under an influence of the gravity. In this situation, however, it is necessary to apply an additional valve, which would stop outflow of a liquid from said dispenser and its dripping after finishing of dispensing process.

The dispensing device according to the invention is designed for cooperation with any type of flexible packaging, for example, a "pouch", "doypack", "cheerpack" type having a spout, in which the liquid content can outflow by influence of a gravity force.

The dispensing device according to the invention can also be used to dispense a liquid from flexible lines, which are under substantially constant pressure of said liquid. In this case the device comprises a valve assembly provided with a resilient element, wherein said resilient element, for example a valve spring, has to be matched to a predetermined pressure and fulfil the following relation:

pressure differential of a pressure in a conduit (cp) and a pressure (cz _in i _et ) at which an inlet valve opens is less than the pressure (cz _outlet ) at which an outlet valve opens, for example, a "Duckbill" type or dome valve, as follows:

(Cp) - (CZ inlet) < (CZoutiet)

To ensure an outflow of liquid and complete emptying of a packaging, said flexible packaging, for example a "doypack" type, is placed such that its spout is directed downwardly. For this purpose, a special grip of a "doypack holder" type is used, available under the trade brand "teemer" shown in Fig. la or alternatively, if a flexible packaging, for example a "doypack" type, is provided with a hanging hole positioned opposite a packaging spout of said packaging it can be hanged with that hole on a special rack, as shown for example in Fig. lb, or on a suitable hook.

Figs, la and lb show exemplary solutions according to the invention, wherein a flexible packaging P, preferably in the form of a sachet or container of a "doypack" or "cheerpack" type (Fig. la) is arranged in such a way that its outlet nozzle, hereinafter also referred to as "spout", is facing downwardly, in a holder HP provided with a suitable opening in which an outlet nozzle or the spout of the flexible packaging, for example a "doypack" type is located. Fig. lb shows attaching method of a flexible packaging provided with a respective hole for hanging, located on its side opposite to the spout, by which hole the packaging is hanged on a suitable catch HK, for example in the form of a hook. A spout of a flexible packaging P is connected directly or via a suitable adapter to the dispensing device D according to the invention.

The dispensing device D according to the first embodiment of the invention, as well as according to further embodiments of the invention described herein and covered by the protection scope of the invention, comprises a device body 1 made, for example, of plastic material or hardened resin, which is fixed directly or via an adapter device i.e. an adapter, to a nozzle or spout, i.e. an outlet opening, of a flexible packaging P, for example "doypack" type. The body 1 in the preferred embodiment according to the invention can have a generally cylindrical shape and is formed with a flange on its side wall for fixing a resilient bellows and with two, preferably located opposite to each other and substantially perpendicularly to an axis of said flange, inlet and outlet openings with nozzles which are positioned preferably on other surfaces of the body 1, for example, defining basis walls of its cylindrical shape, wherein said inlet and outlet nozzles can be integrated into one continuous elongated element, preferably tubular.

The device body 1 according to the first embodiment is made in the form of a substantially cylindrical element, which limits inside its outer surface an inner space la, preferably in the form of an inner opening la, and particularly preferably in the form of a tubular member, wherein said cylindrical body is provided with an inlet fitting and outlet fitting, enclosing an inlet nozzle and an outlet nozzle, which nozzles are preferably arranged opposite to each other. A resilient bellows 9 is attached to one side wall of the body 1, while said inlet and outlet nozzles formed by the inlet and outlet fittings, respectively, which can have a form of a tubular members with a hole running through its entire length, are generally arranged on another side walls of the body 1. In one preferred embodiment they are arranged, opposite each other in such a way that they do not disturb rotation of an adjusting member 8, preferably, in the form of an adjusting nut 8. On one side of the body 1, in its inner space la, preferably in the form of through opening la, an inlet fitting 2 is attached defining an inlet opening which is adapted to be connected directly or via an additional adapter to said spout of a flexible packaging P. The inlet fitting 2 has an internal bore forming inlet opening 2a being in fluid communication with the internal through opening la, which forms an inner space la of the body 1, via a valve element 6 and an inlet slot open to the outside, in a preferred embodiment a threaded inlet slot. At the other end, or on the other side wall, of said internal opening la of the body an outlet fitting 3 is attached forming an outlet nozzle with an outlet opening 3a, preferably axial nozzle, has a shape matching a shape of a body slot to be placed in said body slot adapted to this in such a way that said internal opening la of the body is in fluid communication via a valve element 4 to an outlet opening 3a. On one side wall of the body 1, preferably substantially perpendicular to the sides on which the inlet and outlet fittings are arranged, on its side surface there is located, preferably centrally, a connection opening 11, surrounded by a flange lc projecting outwardly from a surface of the said side wall of the body 1, wherein the axis of said connection opening 11 is approximately perpendicular to an axis of the inner space la, which is an internal opening la of the body 1. Both inlet fitting 2 and outlet fitting 3 are non- slidable and non-rotatable mounted in the body 1 by means of known suitable fixing means such as forced fixing or interference fit, gluing, welding or by a screw connection or another similar means, wherein preferably the inlet fitting 2 may be replaceable element to adapt it to a shape and dimensions of a respective cooperating spout thread of a packaging P. In other embodiments, in some cases, a threaded portion of the inlet fitting may be in the form of a movable screw cap to facilitate screwing down.

In the first embodiment of the invention both the inlet and outlet fittings 2 and 3 are further provided with catch elements 7 projecting towards an axis of the connection opening 11 from respective basis surfaces of said fittings 2 and 3 arranged on that side of the body 1, within which said connection opening 11 is located and surrounded with said flange lc as shown in Figs. 2a-2c, wherein said catch elements 7 are so shaped as to be located at a distance, both from the surface of the side wall of the body 1 facing them and from the surface of the flange lc, thereby limiting, in a preferred embodiment, a receiving space 7a. Said receiving space 7a is defined between said outer surface of the flange lc, a surface of the side wall of the body 1 on which the flange lc is arranged and an inner side of said catch elements 7.

The resilient bellows 9 made of elastic and flexible material such as, for example, LDPE, polypropylene, thermoplastic elastomer or rubber is tightly attached to the body 1 in an area of the connection opening 11 in such a way to close said connection opening 11. The resilient bellows 9 is formed with its side wall surface having generally cylindrical outer contour and comprising folds F of the resilient bellows. In the preferred embodiment said folds F are in the form of helical coils forming said folds, wherein the resilient bellows has at least one such coil or fold forming its side surface, and preferably said bellows 9 has more than two, in particular, several bellows folds or coils which are screw-shaped and defining an inner hollow space 9a of said bellows. Said inner hollow space 9a is closed on one side by a bottom 9b of the bellows 9, while on the other side it is connected to the connection opening 11 of the body 1, wherein from the side opposite to said bottom 9b, the resilient bellows 9 is tightly attached to the cylindrical body 1, in particular to the flange lc of the body 1 and its position relative to the body 1 is fixed, e.g. by pulling on, gluing or welding or other known method.

The end of the resilient bellows 9 opposite to the connection opening 11 is closed by a flat bottom base in a form of a bottom 9b of a bellows. The inner space 9a of said bellows 9 is in fluid communication through connection opening 11 with an inner space la, defined preferably by said inner opening la of the body 1, forming together a dosing chamber KDZ having a determined volume, wherein said volume may be further substantially smoothly and stepless adjustable by setting an inner volume of the inner space 9a of the bellows 9.

In the basic constructional version the resilient bellows

9 has a predetermined volume, preferably marked on said bottom 9b of the bellows, which bottom is simultaneously a pressing place, i.e. defines a surface on which pressure in an axial direction of the bellows and directed towards the body is applied by a user during dispensing. In such a case, each pressing results in an outflow of a predefined amount of a liquid to be dispensed from an outlet fitting 3a.

In another embodiment, being structurally more advanced and versatile variant of the invention, it is possible to change a metered volume of a liquid by dispensing device according to the invention, for example, in the first embodiment said change is performed by changing a useful volume of the resilient bellows 9, and particularly a volume of its inner space 9a, and thus a volume of said dosing chamber KDZ of the device according to the invention, that is conducted by means of an assembly for stepless, smooth adjustment of a volume of a liquid to be dispensed. In this embodiment, by adjusting a volume of an inner space 9a of the resilient bellows 9. In the first embodiment, said assembly for stepless adjustment cooperates with folds F of the resilient bellows 9, preferably in the form of helical coils Z constituting said resilient bellows 9, and comprises an adjustment or a control element 8, which element surrounds from the outside a side wall surface of the bellows 9 at least on a certain part of its length.

Such adjustment element of an assembly for smooth adjustment of a volume according to the preferred embodiment of the invention is in the form of an adjusting nut 8 placed on the resilient bellows 9 and arranged around its outer circumference, which adjusting nut 8 is preferably made by injection moulding of plastic material, preferably of a thermoplastic material such as PA, PP, ABS, POM-C, PET and it is provided with an internal thread 8a dimensionally adapted to a shape and dimensions of the helical coils Z of the bellows 9. The adjusting nut 8 is secured around an outer periphery of the resilient bellows 9 with possibility for rotation relative to the bellows 9, which is fixed to the body 1 but in the first embodiment said nut 8 has no possibility of longitudinal displacement in axial direction relative to the bellows. Such displacement or axial shifting of the adjusting nut 8 is prevented by said catch elements 7, preferably in the form of projections or projecting elements projecting from inlet fitting 2 and outlet fitting 3, as discussed above, wherein, in this embodiment, on its one end side, the adjusting nut 8 is mounted and locked against shift movement in a receiving space 7a formed by said catch elements 7. Internal thread 8a of the adjusting nut 8 includes, in embodiment of the invention, only one turn, preferably, incomplete thread turn, that means a turn extending about less than 360°. Wherein at the beginning portion of an internal thread 8a of the adjusting nut 8 viewed from front side of the nut the thread 8a begins with a radial offset. Said radial offset prevents flexing of the resilient bellows 9 and more particularly its coils Z during rotations i.e. turning the adjusting nut 8 around relative the resilient bellows 9 and it enables smooth rotations of the adjusting nut 8 without jamming. The radial offset has inclined surfaces of its sides, that means end surfaces of a profile of its thread, and can be determined by an offset angle a, which is an angle defined between the line passing through the geometric centre of central axial opening of the adjusting nut 8 and a line running tangentially to said inclined end surface of a profile of the inner thread 8a, as shown in fig. 3. In the preferred embodiment, the offset angle a is in the range from about -30° to 45°, in particular from -30° to 30°, preferably in the range from -15° to 15°, and particularly preferably about 10°.

An angle of the inner thread 8a inclination is in a preferred embodiment approximately close to the angle of symmetric trapezoidal thread and is preferably about 30 degrees. Such an angle of the thread of the adjusting nut 8 facilitates tight arrangement of helical coils Z of resilient bellows 9 in an adjustment space 8d formed between said adjusting nut 8 and the body 1, in particular between a projection 8b of the nut inner thread 8a turn and a front surface of the flange lc of the body 1, and does not require large forces while turning the adjusting nut 8. According to the invention it is important to select suitable plastics materials or curable resin, of which both cooperating elements, namely the resilient bellows 9 and the threaded adjusting nut 8 are made, which elements cooperate together to ensure self-locking mechanism, wherein for the majority of pairs of plastic materials, of which said cooperating elements are made, and especially for the bellows 9 made of a rubber or thermoplastic elastomers and the adjusting nut 8 made preferably of plastic, more preferably of thermoplastic material, such as, for example, PA, PP, ABS, POM, the nut thread is self-locking.

In case of resilient bellows 9 made of materials having low coefficient of friction, such as for example Teflon, on a surface of the threaded adjusting nut 8 on its inner thread 8a surface as well as on the resilient bellows 9 additional locking elements, preferably in the form of projections or teeth which can prevent unintentional unscrewing of the adjusting nut 8 should be used. Such locking elements (not shown in figures) maintain the adjusting nut 8 during its rotational motion, while arresting it in a predetermined position by means of a shape-coupling joint. By turning around the adjusting nut 8, a working length of the resilient bellow 9 is changed, that is a length of the bellows on which it can flex under influence of a pressure can be exerted by a user by pressing with a hand or finger on the bottom 9b to dispense a liquid. Namely, in the first and second embodiments of the invention, during turning around the adjusting nut 8 a part of one helical coil or several helical coils of the resilient bellow 9 is "screwed in" and clamped and locked in a compressed state in the adjustment space 8d between the internal thread 8a of the adjusting nut 8 and the front surface of the flange lc of the body 1, or "screwed out", i.e. released from that adjustment space 8d, whereby said working length of the resilient bellow 9 is changing. A change of said working length of the bellows implies a change of a volume of the bellow inner space 9a, and thus the volume of a useful part of the bellows, in which a liquid to be dispensed is collected. By turning the threaded adjusting nut 8 around in the direction which depends on a kind of its thread used i.e. right- or left-hand thread, rotating it in one direction reduces said volume and rotating it in the other (opposite) direction increases said volume of the inner space 9a of the bellows, and thus a dispensed volume, wherein a respective compressing and clamping of a certain portion of the resilient bellows 9 coils in the space formed between an inner side of the projecting inwardly thread 8a of the adjusting nut 8 and facing to it surface of a side wall of the body 1, in particular the front side of the flange lc surrounding the connection opening 11 of the body 1, is carried out, as shown in fig. 2c, thereby decreasing a number of free coils of the resilient bellows 9, which may flex during pressing the bottom 9b of the bellows 9, and thus the volume of the inner space 9a.

Pressing on the bottom 9b of the bellows in a direction to the body 1 causes squeezing and compressing the bellows 9 and thus causes its axial deflection, and this results in squeezing out of a liquid contained in the bellows 9 inner space 9a through the opening 11 of the body 1 and further pushing out a liquid to the outside through the outlet opening 3a of the outlet fitting 3.

To prevent retraction of a liquid to the packaging P, during pressing the bellows to dispense a liquid, a valve element 6, preferably a valve, for example in the form of a ball 6 biased by a spring 5 is arranged between the inlet opening 2a of the inlet fitting 2 and the inner space 9a of the resilient bellows 9, constituting a working chamber of the dispensing device of the invention.

To prevent sucking an air from the outside, and at the same time to prevent dripping of a liquid from the outlet 3 of the device it is preferably to use a valve 4 in the opening 3a of the outlet fitting 3, which may be, for example, preferably, an elastomeric valve of "Duckbill" type or a domed valve with a slit, which is known in the art and now often used e.g. in packaging of ketchup, honey or syrups. A valve 4 is biased by the outlet fitting 3 to the body 1 in a sealed manner .

Fig. 2b shows operation of the dispensing device in the first embodiment, i.e. the dispenser according to the invention at the time of pressing on the resilient bellows 9. A liquid outflows in this embodiment from the inner space 9a of the bellows 9 through the opening 11 and the elastomeric valve 4.

Fig. 2c shows the dispensing device according to the invention in the first embodiment, which presents a method of stepless adjustment by a user a volume of liquid dispensed by the dispensing device, in this case a volume of a dosage was reduced, in which purpose a useful (working) volume of the resilient bellows 9, i.e. its inner space 9a is reduced by turning around the adjusting nut 8. In this embodiment, a part of the resilient bellows 9, i.e. a part of its coils Z, is compressed and arranged in arrested manner in a space between the inner thread 8a of the adjusting nut 8 and the body 1, in particular the surface of the flange lc.

The dispensing device according to the invention, in the first embodiment operates in such a way that by turning around or rotating the threaded adjusting nut 8 a user regulates and adjusts a length of the free portion of the bellows 8, i.e. a number of the free helical coils Z of the resilient bellows 9 that are not compressed and arrested by the nut 8 and thus adjusting a volume of its available inner space 9a.

On the adjusting nut 8 can be arranged suitable scale indicating particular dose volumes, for example, by means of digits or numerals (e.g. 2, 4, 6, 8, 0), which can indicate a volume change in units, for example in millilitres. These digits or numbers may be indicated by a marker, preferably applied to the catch element 7. One full rotation of the nut can indicate a volume change by e.g. 10 ml, in addition tags can be applied to individual coils or folds of the bellows, for example: 10 ml, 20 ml, 30 ml, which can indicate a volume of a liquid to be dispensed. In a release condition, the entire bellows 9 is free that means all its coils or folds are outside of adjustment space 8d and by pressing on it a full dose can be dispensed, for example, 30 ml of a liquid. After turning the adjusting nut 8 a part of the bellows 9 portion, i.e. a part of its folds or helical coils, is squeezed and pressed under the adjusting nut 8 and thus closed in the adjustment space 8d, thereby these coil or folds are not involved in dosing. Thus, the two full turns causes a change of a dispensed volume of about 20 ml. So that, pressing the bellows 9 in such a position makes dosing only 10 ml of a liquid.

Another embodiment of the dispensing device according to the invention, i.e. the second embodiment, is shown in figs. 5a-5d, wherein the same or similar structurally and functionally constructional elements as for the embodiment shown in_. figs. 2a-2c are designated with the same reference numerals and have the same names.

Fig. 5a shows a dispensing device D comprising, as in the previous embodiment, the device body 1 consisting of a longitudinal portion which at its opposite ends is connected to two fittings, an inlet 2 and an outlet 3, forming inlet and outlet nozzles, arranged opposite to each other. In the device body 1 on one end, an inlet fitting 2 with an inlet opening 2a are mounted, and, preferably, on the opposite end, an outlet fitting 3 with an outlet opening 3a are mounted, in which opening 3a a valve element 4, preferably in the form of elastomeric valve 4, is mounted. Both inlet fitting 2 and outlet fitting 3, forming inlet and outlet nozzles, respectively, are provided with catch elements 7, preferably hook-shaped, having similar construction and arrangement as in the first embodiment shown in figs. 2a-2c, for locking slidable movement, i.e. a linear displacement of an adjusting nut 8 relative to a resilient bellows 9 and the device body 1. The body 1 has an internal, preferably approximately axial, longitudinal central opening, defining an inner space la of the body 1 and a connection opening 11 arranged on a side wall surface of the body 1, transverse to its axis, and preferably perpendicular to said axis which opening being in fluid communication with the inner space la and which is surrounded by outwardly projecting flange lc. At the same side wall of the body and to the body 1 and especially to the flange lc surrounding the connection opening 11, as in the previous embodiment, a resilient bellows 9, having a contour generally similar to cylindrical shape, is attached by its open end side. Such resilient bellows 9 is formed as composed of a certain number of folds F in the form of helical coils Z, forming the folds along its full length, as in the first embodiment shown figs. 2a-c, while the second opposite end of said resilient bellows 9, distant to the body 1, is closed by a bottom 9b. In this embodiment, in the bottom 9b is additionally mounted a plug 10 which may be, however, alternatively omitted. The plug 10 stiffens the bottom of the bellows that results in more accurate dosing, and in addition it can perform decorative or advertising functions (e.g. by bearing a logo) . The plug 10 may also be used in the case of the bottom 9b of the bellows 9 in the first embodiment shown in figs. 2a-c.

As in the first embodiment shown in figs. 2a-c, the dispensing device D according to the invention is provided with an assembly for stepless and continuous adjustment of a volume of a dispensed liquid, in this case by adjusting a volume of the inner space 9a of the resilient bellows 9, and thus the dosing volume KZD. The assembly for stepless adjustment cooperates with helical coils Z of the resilient bellows 9, constituting its folds, and preferably comprises a control element 8 which surrounds from outside a side circumferential surface of the bellows 9 at least on a certain portion of its length. The assembly for stepless continuous adjustment of a volume as in the previous embodiment comprises an enclosing element in the form of an adjusting nut 8 disposed around the outer circumferential surface of the resilient bellows 9, which nut is provided with an internal thread 8a, adapted in size and shape to the size of the helical coils Z of the resilient bellows 9, wherein said internal thread 8a of the adjusting nut 8 comprises preferably one, particularly one incomplete thread turn that means a turn not extending about full 360° thread but less than 360°, wherein said internal thread is formed in the same manner as in the case of the adjusting nut for the first embodiment according to figs. 2a-c. The adjusting nut 8 is rotatably mounted relative to said resilient bellows 9 but, in this second embodiment, also non- displaceably relative to the resilient bellows 9 and at the same time relative to the body 1, as in the case of the first embodiment shown in figs. 2a-c.

The difference in construction between the first and second embodiment of the dispensing device D, respectively, shown for example in figs. 2a-2c and 5a-5d lies in that additionally two valve elements, namely an inlet valve 15 and outlet valve 16, are positioned in the connection opening 11 of the device body 1 and further in providing a recess 20 on a side surface of the body 1, opposite to the connection opening 11 which recess 20 having side walls inclined at an angle and converging towards the inside, for example forming in cross- section a V-shape, wherein said inclined walls of the recess 20 divide said central through opening la forming an inner space la of the body 1, which is shown in the first embodiment of figs. 2a - 2c, into two separate sections of said central opening, forming a partial opening 1.1a and partial opening 1.1b as shown in figs. 5a-5c. Said partial opening 1.1a is connected to the inlet fitting 2 and is in fluid communication with its inlet opening 2a on one hand, and through the valve element 15 located in this part of the connecting opening 11 with said inner space 9a of the resilient bellows 9, while the partial opening 1.1b is in fluid communication with a valve element 4 having outlet opening 3a of said outlet fitting 3 on one hand, and on the other hand through the outlet valve 16 with said inner space 9a of the resilient bellows 9.

The recess 20 may be located substantially centrally along the length of the body 1 and in each case opposite the connection opening 11, on the opposite wall of the cylindrical body 1 relative to the connection opening 11, and at the height of said connection opening 11 in such a way that an internal apex of the recess 20 reaches the connection opening 11 and divides it into two portions, an inlet portion of said opening 11 and an outlet portion of said opening 11 in a form of said inlet and outlet partial openings. In the inlet portion of the connection opening 11 an inlet valve 15 is provided while in its outlet portion an outlet valve 16 is provided. In the recess 20 on one of its inclined walls, in a suitable hole in said wall, a button member 12 in the form of a press button is provided, which is secured against falling out by a latch 14, placed, preferably, on another wall of said recess, particularly preferably, an opposite wall with respect to the recess 20. A button member 12 is sealed in respective opening of the recess wall by a gasket 19 and may be biased by a spring 18 of said button member 12 and it is used to open the inlet valve 15 when performing adjustment of the dispensing device to decreasing dispensed liquid volume, i.e. during turning the adjusting nut 8 in suitable direction, reducing a number of available free helical coils Z of the resilient bellows 9, which may flex during dispensing, to prevent uncontrolled outflow of a liquid through the valve 3.

The recess 20 makes possible to move the button member 12 therein and preferably for ergonomic and technological reasons has a V-shape or similar to a V-shape.

The inlet valve 15 and outlet valve 16 can be formed as one common elastomeric or rubber membrane with two slits or in the form of two adjacent separate membranes, each of which is shaped in a semicircle-shape with a corresponding slit shown in fig. 4. The membrane or membranes is/are attached to the device body 1 in a region of the connecting opening 11 by pressing insert 17.

Operation of the dispensing device, as well as adjusting and setting of a dispensed volume of a liquid are the same as in previously described first embodiment shown in figs. 2a - 2c and as shown in figs. 5a-5d, in which sequential functional positions of component elements of the dispensing device according to the second embodiment illustrates successive steps and stages during operation of the device. The individual drawings show respectively:

Fig. 5a - presents a position in a release stage of the dispensing device. By using a different shape of the resilient bellows 9 with the membrane which has been stiffened by the plug 10 smaller dead volume of said bellows was achieved and the device demonstrates particularly good operation in relation to dispensing liquids with increased viscosity, for example such as: washing liquids, soaps, certain concentrated detergents, concentrates and syrups of food industry. The plug 10 also prevents deformation of the bellows under pressing, and thus increases accuracy and repeatability of dosing.

Fig. 5b - shows an operation stage after pressing the resilient bellows 9 by the plug 10 in axial direction towards the body 1 which causes increasing pressure in the dosing chamber formed by the inner space 9a of the bellows 9, causing opening the outlet valve 16 and outflow of a liquid through the valve element 4.

Figure 5c - shows operation stage of the device D after releasing the pressure on the resilient bellows 9, for example imposed by an optional plug 10, in which stage the bellows 9 returns to its initial state under action of its own resilience as well as under pressure of a liquid inflowing to the inner space 9a or a chamber of the bellows 9 through the inlet valve 15.

Fig. 5d - shows a way of regulation and adjustment of a dosing volume of the device. By turning around the adjusting nut 8 along the helical contour of the bellows folds, that means along helical coils Z of the resilient bellows 9, the number of the free folds, i.e. helical coils, that can be subjected to deflection under axial pressure is reduced, and thus the inner space 9a forming the working volume of the bellows, and therefore the dosed liquid volume KZD, is reduced.

Fig. 4 shows a detailed view which schematically shows a view of the inlet valve 15 and outlet valve 16, which in this embodiment are formed as a slit in one resilient element (made of elastomer or rubber) forming a common membrane, wherein each said slit have the U-shaped contour or approximate to the "U"-letter shape, while said resilient element is held by the insert 17 pressing the valves 15, 16 to the body 1 in a region of the connection opening 11.

The button 12 serves to open the inlet valve 15 during adjustment of the device when decreasing the dosing volume, (i.e. during turning the adjusting nut 8 in the suitable direction) to prevent uncontrolled outflow of liquid through the outlet fitting 3. Excess of a liquid is returned back into the input connector called the inlet fitting 2 in this description. Said button spring 18 causes automatic return of the button 12 to the release position after releasing pressure on the button 12 and after completion of adjustment of the dosing volume of liquid by turning the adjusting nut 8.

The dispensing device D according to the invention can be adapted to different types of flexible packaging provided with spouts having various contours of thread by applying various internal threads of the inlet fitting 2 thanks to possibility to be connectable to cylindrical device body 1, for example by pressing-in or other type of connection means, different fittings adapted to specific threads used in flexible packaging, for example Doypack type. The advantage of this solution is that the complex shape of the body 1, preferably cylindrical, can be performed in one mould, and relatively simple and cheap to manufacture inlet/outlet fittings can be produced in various moulds, resulting in improved economics of manufacture of the dispenser. Another variant of the dispensing device according to the invention in the form of the third embodiment is shown in figs. 6a-6c. As in the first embodiment shown in figs. 2a-c, as well as in the second embodiment shown in figs. 5a-5d, the constructional components which are structurally and functionally similar are designated by the same reference numerals. The dispensing device D in this embodiment of the invention is provided with the device body 1, as in the previous embodiments, comprising a longitudinal part having at its opposite ends connected fittings, the inlet fitting 2 and outlet fitting 3, forming the inlet and outlet nozzles, preferably opposite to each other. In this embodiment the inlet and the outlet fittings 2 and 3 are preferably not provided with catch elements 7 projecting in a direction of an axis of a connection opening 11 from their respective basis surfaces, although they may alternatively be present. In this case, they have to be so designed in terms of dimension to prevent excessive unscrewing an adjusting nut 8, for example, they can be elongated. The body 1 has an internal, preferably approximately, axial longitudinal central opening la, defining an inner space la of the body 1 and a connection opening 11 arranged on a side wall surface of the body 1, transverse to said central opening and preferably perpendicular to it. Said connection opening being in fluid communication with the inner space la and it is surrounded by an outwardly projecting flange lc. From that side, to the flange lc surrounding said connection opening 11, as in the previous embodiments, a resilient bellows 9, having a contour generally similar to cylindrical, is attached with its open end, which bellows 9 is formed as composed along its length of a certain number of adjacent folds F of the bellows 9, preferably in the form of circular folds F, wherein alternatively, said folds can have a form of helical coils, while an opposite second end of the resilient bellows 9, which is also opposite to the body 1, is closed by a bottom 9b, wherein in this embodiment, in the bottom 9b a plug 10 is additionally mounted.

As in the embodiments shown in figs. 2a-c and figs. 5a-d, the dispensing device according to the invention is provided with an assembly for stepless, continuous adjustment of a volume of dispensed liquid, in this case by setting up a working volume of the inner space 9a of the resilient bellows 9, and thus the dosing volume KZD. According to this embodiment, said assembly for stepless and continuous adjustment of a dosing volume, however, is realized not by changing internal working volume of the bellows 9 that is a number of its free coils or folds, but by limiting possible, available degree of deflection of the bellows 9 under axial pressure, that limitation is realized by means said adjusting nut 8, namely, by limiting a number of folds F or coils that can deflect, while exerting pressure on the bottom 9b during dispensing, which number is limited by a change of the adjusting nut 8 position.

The assembly for continuous, stepless adjustment of a volume as in the previous embodiments comprises a control element 8 in the form of an adjusting nut 8 having a groove 8e on and around its inner surface, forming, preferably, one turn of an internal thread 8e, cooperating with corresponding projection W provided on outer surface of a flange lc of the body 1. The internal thread 8e is dimensionally adapted to dimensions of the projection W on the flange lc of the body 1, wherein said internal thread 8e of the adjusting nut 8 comprises preferably one, particularly preferably one incomplete, thread turn, namely extending about less than full 360° turn while a pitch of the internal thread is smaller than total length of the adjusting nut 8. Said internal thread itself, acting as a guide groove 8e, preferably begins at the front of an outer front surface of the adjusting nut 8 and terminates at certain distance, preferably 1 - 2 mm, from the other front surface of said adjusting nut 8 in order to prevent unscrewing said adjusting nut 8 from the body flange lc.

The projection W on the flange lc has to be able to slight deflection to facilitate assembly. This can be obtained by providing side slits in its side wall.

In this embodiment, the adjusting nut 8 is pivotally and slidingly mounted relative to the resilient bellows 9, and at the same time relative to the body 1. This is different construction from the first and the second embodiments shown in figs. 2a-c and 5a-d.

Said internal thread 8e may be rectangular, trapezoidal or metric. Depending on surface parameters and material of the adjusting nut 8 and the body 1, it is preferably to select such a thread which is self-locking, that is, if the inner diameter of the nut is d and a pitch of internal thread 8c is s coefficient of static friction μ should be selected as greater than tangent s/nd {Tg s/πά) .

The internal thread 8e of the nut 8 cooperates with a projection W on the flange lc that matches its shape and dimension to the contour of the thread with a slight clearance .

Total length of the adjusting nut 8 is at least equal to total length of the flange lc, but may be bigger, i.e. the adjusting nut 8 can be longer than the flange lc.

This solution allows to presetting of a volume of dispensed liquid without using a button 12 as presented in the second embodiment shown in figs. 5a-5d. The internal volume of the internal space 9a of the resilient bellows 9 does not change during adjustment of a volume of a liquid dose. The bellows can be either in its traditional form, i.e. consisting of circular folds F or of helically shaped coils, that is it can be also composed of helical coils Z, as in the previously described embodiments. The bellows is attached, unlike as in the first and second embodiments, to inner surface of the flange lc by means of shape-joint-coupling on a shape- connection principle and/or by gluing or welding. Such configuration allows placing the control element in the form of the adjusting nut 8 about the outer surface of the flange lc of the body 1 that is different from the first and second embodiments, while in these previously presented embodiments the nut 8 is placed around outer surface of the resilient bellows 9. In this embodiment, the bottom 9b of the bellows 9 has an enlarged diameter with respect to the bellow 9 diameter as compared to previously presented embodiments. Preferably, a diameter of the bottom 9b of the resilient bellows 9 in the third embodiment is at least equal to an outer diameter of the adjusting nut 8, alternatively it can be larger.

Fig. 6a - shows the release stage position of the dispensing device in the third embodiment of the invention in which a dispensed maximum volume position of selected liquid is set up.

Fig. 6b - shows a way of adjusting of a selected dose volume of the dosing device. Turning around the adjusting nut 8 a user changes its position with respect to the resilient bellow 9 and to the body 1 because it moves forward or backward with a rotation in direction away from the body 1 or towards the body 1, depending on type of its internal thread 8e, thereby changing available free length of the bellows 9, (i.e. its length which is outside the nut 8) the number of free folds of the bellows 9 which can be subjected to flexing under pressing the bottom 9b or plug 10 in axial direction towards the body 1, thereby regulating the volume KZD of a liquid that can be dispensed.

Fig. 6c - shows a state after pressing on the resilient bellows 9 by the plug 10 in axial direction towards the body 1, which results in increasing pressure in the dosing chamber, i.e. in the inner space 9a of the bellows 9, and thus outflow of a liquid through the connection opening 11 to the valve element 4 and out from the outlet fitting 3.

The above-described embodiments of the dispenser according to the invention, especially their constructional features and adequate structural solutions may be used not only in the way described exemplary in the above description but also in various possible constructional combinations and structural solutions. For example, in the third embodiment of the invention an inlet valve 15 and an outlet valve 16 can be used. In addition, when the adjusting nut 8 cooperates with a surface of resilient bellows shaped in the form of helical coils and can perform more than one rotation, the auxiliary markings, for example numeric, e.g. 10, 20, indicating the set out volume can be applied on such individual folds of the bellows in the first and second variant and additionally such auxiliary markings can be placed at outer portion of the flange lc of the body 1 in the third variant, in order to further facilitate operation of the dispensing device.

List of references

1 - a body

la - an internal space of the body

lc - a flange of the body

11 - connection opening of the body

2 - inlet fitting/ input connector

2a - inlet opening

3 - outlet fitting

3a - outlet opening

4 - discharge valve, for example, elastomeric

5 - a spring

6 - a ball

7 - catch elements

7a - receiving space

8 - adjusting nut (control element)

8a - internal thread of the nut 8b - protrusion of the internal thread

8d - adjusting space of the nut

8e - internal thread in the form of a guide groove

9 - resilient bellows

9a - inner space of the bellows

9b - bottom of the bellows

10 - a plug

12 - a button

14 - latch preventing the button 12 to fall out

15 - inlet valve

16 - outlet valve

17 - insert for biasing valves (pressing insert)

18 - spring of the button

19 - a gasket

20 - a recess

P - packaging (sachet, doypack, cheerpack)

D - dispensing device (dispenser)

HD - packaging holder, for example Doypack type

HK - catch (hook) for the packaging, for example doypack type - required opening in the container opposite the spout

KDZ - dosing chamber (equivalent to 9a)

Z - helical coils of the resilient bellows 9

F - folds of the resilient bellows 9

c - offset angle of the internal thread 8d

- projection of the body flange