NL8200969A - METHOD AND APPARATUS FOR DELIVERING VARIOUS VOLUMES IN VARIABLE VOLUME OF VISCOUS CONCENTRATES WITH VARIABLE VISCOSITY - Google Patents

Description

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Method and device for dispensing viscous concentrates with variable viscosity in accurately dosable quantities with variable volume.

The invention relates to a method and a device for dispensing viscous concentrates with variable viscosity in accurately dosable quantities with variable volume, wherein by cyclical change of the pump volume of a hollow body of flexible or in shape resilient material via a non-return valve. concentrate is drawn from the storage volume of a container and is expelled through a second non-return valve on the dispensing side.

Dispensing sections designed as a metering pump with two non-return valves serving as inlet 10 and as outlet are known in very different embodiments. For example, e.g. British patent specification 827.T78 comprises a metering pump, the dispensing part of which is designed as a hose, which can be flattened radially by means of an operating device and which again takes up its full cross section through its own spring force.

Depending on the pressure change in the dispensing section, the inlet valve resp. the outlet valve. Such an embodiment is difficult to handle and moreover allows only a relatively inaccurate dosing. Devices of this kind are therefore suitable for soap dispensers and the like, where it is not so much a question of dosing accuracy. In addition, the devices serving to operate the dispensing portion are extremely expensive.

However, it is also already known to provide the bellows with a radially outwardly projecting bellows-forming pleat which can be compressed in axial direction between plate-shaped operating elements in order to act as a dosing pump. In this case, too, the dispensing part can be designed as a rubber bellows, to which matching beak-shaped rubber valves have been added as non-return valves (see US patent 2.55-570). These well-known devices also require considerable space and are therefore unsuitable for mounting in vending machines and the like. Also, the dosing volume is relatively inaccurate, making accurate dosing extremely difficult.

5 When dosing certain highly viscous concentrates in a dosed manner, a very accurate dosing is required. Because the e.g. the installation space available in beverage vending machines is extremely small, the dosing device must be designed to save as much space as possible. A very special problem is that concentrates of perishable organic substances present extremely great hygienic problems, especially when the dosing device or the associated parts are contaminated with drops of such substances. The maintenance and frequent cleaning of the parts required thereby is extremely laborious and heavy, and requires strict supervision if all hygienic requirements have to be taken into account.

In hitherto known metering devices with a hose pump or the like hose-shaped dispensing part, the resilient resetting force of the hose part is relatively small with only small changes in shape of the resilient hose material. The restoring force also only increases with larger deformations. However, the magnitude of the restoring force also influences the precise repeatability of the shape change and thus the accuracy of the metering. With these devices, therefore, only relatively large volumes and with only a relatively small repetition frequency can be delivered. Among relatively large volumes, e.g. volumes

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included from 0.4 cm. A bias in the starting position of the hose sections with a filled hose is also not possible, because the hose sections in the operating device, e.g. peristaltic pump, must be inserted inwards, deformation must not take place in order to prevent liquid drops from escaping.

Another essential factor, which has an unfavorable effect on the dosing accuracy in the known devices, is the fact that during the reduction of the pump volume, the tube-like dispensing part is subjected to uncontrollable further shape changes. increased pressure occurring internally. Also these uncontrollable changes can only be tolerated if relatively large dosing volumes are delivered with each cycle, so that the influence of these changes remains small.

On the other hand, it is the task of the invention to further develop the method and the associated device specified in the preamble, such that the drawbacks outlined are avoided and the smallest quantities can be dispensed with the greatest precision and the highest cycle frequency. The device serving for the eradication of the method must herein be of very space-saving design, so that it can also be easily installed in a narrow space, e.g. a vending machine, or even can be retrofitted.

According to the invention, this task is solved by the features of claim 1, wherein for the stirring of the method, the solution as regards the device having the features of claim h is used.

According to the invention, the pumping action takes place by axially decreasing a cylindrical pump volume, which at the same time is supported externally during the reduction, so that no uncontrolled deformations can occur with the increasing pump pressure and thus no changes in the dosing volume. Thus, even at the smallest dosing amounts per cycle, extremely high precision and metering accuracy is achieved. By axially compressing the cylindrical dosing volume, the condition is provided for biasing the hollow, cylindrical body limiting the pump volume with a preselectable axial bias in the direction of a volume increase in the initial position.

This results in sufficient large restoring forces even with the smallest volume changes. The axial compression of the pump volume in conjunction with the very high accuracy at even the smallest dosing volume, furthermore allows to cycle the dosing cycle at a frequency corresponding to the mains frequency, i.e. at 50 - 60 Hz. The high frequency and the small yet very accurately dosable volume ensure a wide adjustment range of the quantity to be delivered in the to-8200969 language by only controlling the number of dosing pulses. This control can be implemented very simply and reliably with appliances with a mains frequency control.

Despite the bias in the rest position of the pump volume, the dispensing part can easily and securely be inserted into the operating device without unwanted dispensing of liquid droplets. As a result, the hygienic problems are also completely eliminated, as they otherwise occur with contamination of the device. The device is still substantially improved in that all parts important for the operation are enclosed in a rigid guide tube, which is permanently or releasably connected to a container, preferably designed as a single-use item, for the transport, storage and dispensing of the liquid.

Due to the high cycle frequency, a substantially smooth, i.e., virtually continuous dispensing of the liquid is obtained by means of a chain of rapidly successive dosing cycles that can be adjusted in its length at random.

The sleeve-shaped body can only be flexible, whereby additional elements, such as spring elements and the like, provide the required pre-tension and reset. Preferably, however, the sleeve body is formed of resilient material in shape and rigidly connected to rigid hub-like bodies of the check valves.

The small dimensions of the dispensing section allow for installation in an automatic machine when a very small space is required. The further advantage of the new device makes it possible to also equip existing dosing devices with electromagnetic ring coils to switch from a time-controlled dosing to a quantity-controlled or volume-controlled dosing when the time-controlled dosing due to changes in fluid consistency leads to dosing inaccuracies. Such consistency changes do not affect dosing accuracy in the present container arrangement.

The invention is further elucidated with reference to the drawing 8200969-5, in which:

Fig. 1 a front storage, transport and dispensing container with the dispensing section in vertical section;

Fig. 2 shows the dispensing part with exploded parts; 5 and

Fig. 3 is a vertical section of a modified exemplary embodiment of the dispensing portion.

The subject of the invention is preferably a disposable container, which serves for both storage, transport and dosed dispensing. Preferably, the dispensing part is permanently connected to the container during manufacture and is discarded with the container. The holder is therefore a mass article.

The container can herein consist of an outer casing and an internal, flexible, liquid-absorbing pouch and correspondingly shrinking pouch when dispensed. In this case, airing the container for dispensing is not necessary. However, a substantially rigid container may also be provided, to which is added a venting device that can be attached for dispensing.

Furthermore, the container is preferably intended for receiving, storing and transporting, as well as for dispensing organic concentrates.

In the example according to Fig. 1, a container is designed with an external casing 1 and a flexible, shrinking filling container 2. This has a nozzle 3, to which the dispensing part is preferably permanently attached. In Fig. 1, the container is shown in the upside-down position which it occupies when the liquid is dispensed in a dosed manner. In this position, the dispensing portion 6 is inserted through the center opening of an electromagnetic ring coil 5, e.g. fixed 30 is built into a beverage dispenser or dispenser. The electromagnetic ring coil 5 is connected to a matching control device, e.g. makes it possible to operate the electromagnetic ring coil 5 with the mains frequency, whereby the number of frequency vibrations that the ring coil 5 must follow can be set on the control device.

The part 4 has a rigid plastic guide tube 6, which is permanently connected to the nozzle 3 of the container with its "top end". Over its greater length, the guide tube 6 has a cross section widened via the shoulder 35 (fig. 2) and free at the lower end. A rigid, end-sided cover 26 has been added to the guide tube 6, which has an outlet stub 27 in the middle. Both parts 6 and 26 of. in the example shown, the guide tube are connected to one another via a hub-shaped valve body 20, which has an annular flange 22 on its circumference, up to which from which the guide tube resp. the closing lid 2β can be firmly pressed. In this manner, the hub-shaped valve body 20 is also rigidly connected to the guide tube 6 and the sealing cover 26.

Another similar hub-shaped valve body 8 is received with free play in the other part of the guide tube 6 so that it can move freely in the axial direction in the guide tube. A magnetizable sleeve part 7 in the form of a ring anchor is fixedly mounted on a connecting butt-shaped end of the plastic valve body 8, which faces upwards towards the holder 1, with its lower-annular end side resting against the shoulder 9 of the valve body 8. The valve body 8 and the ring anchor 7 thus form a rigid unit, which can be axially moved up and down according to the double arrow 31 as such in the guide tube 6.

The mutually facing ends of the valve bodies 8, 20 have receiving and securing parts 10, 11 and 11 respectively. 19.21 for the sleeve-shaped ends 16 and 16 respectively. 18 of a hollow cylindrical body 15. In the example shown, this is formed of resilient material and thus also designed as a resilient spring element. The illustrated body 15 has thickened end portions 16 and 18 for attachment to the two valve bodies 8, 20, as well as a thinned portion laid in a radially inwardly pleat 17. Through the connection 30 of the hub-shaped valve bodies 8 and 20 via the body 15, a predetermined dosing volume is enclosed between these parts. The starting size of this volume is determined by the resetting action of the body 15 in communication with the inner shoulder 35 of the guide tube 6, against which, in the rest position, the upper annular end face of the anchor ring 7 rests.

8200969. »- 7 -

In the completed example, each valve body has 8 resp. 20 a central bore 12 and 2, respectively, in each of which the stem of a mushroom-shaped and resilient material valve element 1, resp. 25 can be secured by snap action. The conical bead 5 at the stem end locks the valve element against the hub-shaped valve body. The lip-shaped peripheral edge of the cup-shaped head of the valve element 1, resp. 25 will be sealingly placed on the internal end face of the hub-shaped valve body 8, respectively, under the changing pressure. 20. In the internal area thereof, a number of crown bores 10, provided in a crown-shaped manner, are respectively provided. 23 through which bores the liquid can enter or dispense into the dosing volume. can come out from there. The resilient pretension of the material of the mushroom-shaped valve element 1, resp. 25 is sufficient, under static proportions, to pass through the bores 13 and 10 respectively. 23 steps to prevent 15 of liquid. Only when above the static ratio. If pressure changes occur, the lip-shaped circumferential edges of the disc-shaped heads of the valve elements rise from the central end face of the hub-shaped valve body 8, respectively. 20 to allow fluid flow.

Upwards, the stroke of the bouv unit consisting of the valve body 8 and the ring anchor 7 is determined by the internal shoulder 35 of the guide tube 6. Downwards, the stroke of this unit is determined, because during the downward movement the lower end edge of the portion 10 of the hub-shaped valve body 8 abuts the upper annular end edge of the portion 21 of the hub-shaped valve body 20.

By the choice of the length of the parts 10 and 21, the stroke length 30 of the movable unit 7S 8 can be easily changed and accurately adjusted with an unchanged construction. During the movement of the valve bodies 8 and 20 towards each other, the parts 10 and 30 21 enclose the hollow cylindrical body from the outside in a form-retaining manner, so that the body cannot expand radially outwards.

Fig. 1 shows the parts substantially in the original size of a preferred embodiment, in practice the stroke length is selected to be smaller than shown in FIG. 1. The amount of liquid coming out of the connecting stub 27 is determined by the number of pump strokes taking place with the mains frequency. This quantity can be set precisely, in particular, because the volume can be set extremely precisely in a particular case that each pump impulse is delivered, even with a very small size. The liquid is hermetically shielded in the dispensing section against the action of the air oxygen. It is clear that the device can be manufactured extremely simply and inexpensively, and it operates very reliably, in particular the hands. is very simple and very safe, and cannot lead to contamination of the surrounding parts.

The stroke limitation can also be ensured by other stop parts, e.g. on the guide tube.

In order to also radially change the shape of the hollow cylindrical shape. In order to prevent a body in the region of the radially inwardly projecting pleat, it is advantageous to add a rigid support ring to the or each pleat in the region of its inwardly directed comb.

In the first place, it can also be particularly advantageous if the crest of the pleat is helical. In this case, a helically extending and only axially compressible spring element can be added to the comb as support element, which also serves for axially prestressing the hollow cylindrical body 15. This need not then itself be resilient in shape as long as it is sufficiently flexible material exists.

The output side check valve 25 can also be omitted under certain conditions.

To replace the non-return valve, the outlet volume enclosing the pump volume is provided with an outlet stub, which is in free communication with the pump volume. The internal width and length of this exhaust stub are sized such that the internal friction and surface tension of the concentrate in the exhaust stro are sufficient to retain the concentrate column axially unchanged in the exhaust stub with unchanged and increasing pump volume. The state of the unchanged pump volume is the state where the inlet check valve is closed.

8200969 - 9 -

As the pump volume increases, concentrate is drawn from the container into the pump volume.

In practical embodiments of the device in this further developed type, the internal inner width of the pump volume was between 8 and 12 mm. The stroke length could be adjusted between 1 and 2 mm. The stroke frequency was 50 Hz, but could be changed between 10 Hz and 100 Hz without disrupting the operation. Liquids with viscosities between 1 ·. · .Βη 100 units (centipoise) were tested. The inlet non-return valve had as semicircular through holes, slots which could be covered by valve plates. It was determined that with a length of the outlet stub replacing the outlet valve between 10 and 40 mm and an internal width of this connecting stub between 1 and 3 mm, no dropping out of the concentrate was to be feared. 15 Without the corset-shaped support of the bellows, irregular bellows, affecting the dosing accuracy, occur of the bellows. In contrast, the new corset-shaped support allowed volume tolerances of barely measurable size to be maintained.

A modification of the parts determining the pump volume is shown in fig. 3- In the cylindrical housing 40 which can be connected with its upper end to the container for the concentrate, an upper canister 42 is placed, which at its upper end has a outside, has protruding flange. A corresponding lower sleeve 43 is provided in the lower end of the housing 40 and is rigidly connected to a lid having the outlet stub 49. In the two examples, it is assumed that the lower sleeve 43 can slide with play in the lower end of the housing 40o. The lower sleeve 43 also has an outwardly projecting flange. Between the bottom portion of the housing 40 and 30, the two substantially aligned connector stubs 42 and 43, which are made of rigid material, e.g. plastic, a ring space 47 is provided. In this ring space, a spreading spring or biasing spring 48 is provided, which rests with both ends against the flanges of the between 42 and 43, and wants to keep the two sleeves in the spreading position shown in Fig. 33. In the illustrated embodiment 8200969 - 10 - the lower connecting stub is connected to an anchor ring 1 * 5, which can be operated by the electromagnetic device (not shown) so that the lower connecting stub 1 * 3 can be flush with the upper connecting stub 1 * 2 lifted to perform a pump stroke. The mutually facing ends of the two connecting stubs are sealed by a folding membrane 1 * 1 *, but are essentially joined together free of forces. In the approach position of the two connecting stubs 1 * 2, 1 * 3, the fold 1 * 1 * closes practically completely.

10 To prevent compressed air compressions in the annular space 1 * 7 from occurring in the rhythm of the pump strokes, the annular space 1 * 7 is vented to the outside atmosphere via slots or bores 50, with openings 50 as close as possible to the end position of the pump stroke should be in order to obtain a short path for the air moved by the volume changes in the annulus 1 * 7. In the upper flange area of the connection stub 1 * 2, the inlet valve for the pump chamber (not shown) is provided, which can be designed similar to the embodiment described above. The stroke movement of the lower connection stub 1 * 3 is indicated by the double arrow 20 1 * 6. The device could also be arranged in such a way that both connecting stubs are moved towards and from each other. The illustrated embodiment has the advantage that no concentrate can penetrate into the ring space 1 * 7. The connecting stub 1 * 9 can be designed in such a way that it is not necessary to add a non-return valve to the outlet of the pump volume.

It can be seen that such a device, which operates independently of the resilient resetting force of a rubber bellows, can also dose substantially pasty media, which with the normally available resetting force of a resilient body, can no longer be reached. In this case, the magnetic forces must be built up accordingly. The resilience can then also be determined analogously.

The dosing device is also applicable for fluxes other than syrup and the like. Due to the pump parts built into the single-use unit, it particularly contributes to spoilage 8200969 -11-.

good fluids, the advantage that through conscious manufacturing measures the life of e.g. the membrane is limited, so that in the event of unacceptable refilling of the container, the membrane and thus the device quickly becomes unusable. Thus, the occurrence of hygienic problems is effectively prevented.

8200989

Claims (14)

A method for dispensing viscous concentrates of variable viscosity in accurately dosable amounts of variable volume, wherein by cyclically changing the ponrp volume of a hollow body of flexible or resilient material through a non-return valve concentrate of a storage volume of a container is drawn in and ejected through another non-return valve on the discharge side, characterized in that the cylindrical pump volume is cyclically changed between stops in the direction of its longitudinal axis, with the hollow cylindrical body at each volume reduction is supported against changes of shape in radial direction outwards, in shape enclosing from outside. Method according to claim 1, characterized in that the hollow cylindrical body is resiliently biased in the form corresponding to the largest starting volume in the axial direction and in the direction of an increase in the pump volume. Method according to claim 1 or 2, characterized in that the cyclic change of the pump volume is carried out with the mains frequency of the electric power network. k. Device for carrying out the method according to claim 1, comprising a dispensing part designed as a dosing pump, which can be connected to the storage volume of a container, in particular a container for storing, transporting and dispensing the concentrate, and connected to its dispensing end via a non-return valve opening in the dispensing direction, has an axially compressible pump volume 25 and can be inserted into an operating device controlling the pump volume, characterized in that the pump volume is provided in a hollow cylindrical body (15) of flexible or resilient material, to which body an axially compressing actuating element (j) is added to this body, wherein a hollow cylindrical housing is provided, which encloses the hollow cylindrical body in at least the phase of the volume reduction in shape from the outside. Device according to claim U, characterized in that the rigid valve bodies (8, 20) of the two check valves (1, 25) are fixedly connected to the ends of the convex cylindrical body (15) and in axial are movable in a direction relative to each other and have wall sections (10, 21) which, at least in the position of the largest axial approach, enclose the hollow cylindrical body (15) in shape from the outside. Device according to claim or 5S, characterized in that the wall parts (10, 21) of the two non-return valves (1¼, 25) also form the changeable limit stop for the approach movement of the two non-return valves. Device according to any one of claims ¼ - 6, characterized in that one valve body (20) is immovably connected to a guide tube (6, 26), which accommodates the check valves, the actuating element and the hollow cylindrical body, in which the other valve body 15 (8) and the associated control element (7) are axially displaceable. Device according to claim 7, characterized in that the unit of the valve body (8) and the actuating element (7) in the position of the greatest value of the pump volume with predetermined biasing force in the direction of a increasing the pump volume against an internal stop (internal shoulder 35) of the guide tube (6, 26) is biased. Device according to claim 8, characterized in that the hollow cylindrical body (15) consists of resilient material 25 in shape and is clamped in the rest position between the two valve bodies (8, 20) under axial compression. Device according to claims ¼ - 9, characterized in that the actuating element is designed as a ring anchor (7) and can be cyclically moved together with the valve body (8) via an electromagnetic actuating device with the mains frequency between 50 and 60 Hz in the guide tube. 30. 11. Device as claimed in any of the claims ¼ - 10, characterized in that a movable unit is added to the movable unit, this spring element holding the initial tension in the starting position. Device according to any one of claims ¼ - 11, characterized in, 8200969 - 1U - that the thickened ends (16, 18) of the hollow cylindrical body (15) of resilient material in shape, on circumferential parts (11, 19) of the hub-shaped valve bodies (8, 20) are drawn in a sealing manner, the hollow cylindrical body (15) having at least one radially inwardly protruding crease (1T). Device according to any one of claims 1+ - 12, characterized in that the non-return valves consist of mushroom-shaped elements (1U, 25) of resilient deformable material, which are push-button-shaped in a central bore of the plastic hub-shaped valve bodies 10 (8, 20). A device according to any one of claims U-13, characterized in that the guide tube consists of a guide part (6) and an end cover (26), which has a connection butt-shaped outlet (27), which via the plastic body of the fixedly mounted check valve (20) is joined. Device according to any one of claims 12 - lit ·, characterized in that the or each inwardly projecting pleat (17) · is held against radial deformation by a rigid annular support element. 16. Device according to claim 15, characterized in that the comb 20 of the inwardly protruding pleat (17) of the hollow cylindrical body (15) is made of a flexible or of resilient material in a helical form, the support element of which is fixed in the comb embedded, axially yielding coil spring is provided. Device according to claim k, characterized in that the pump volume on the outlet side, instead of via a non-return valve located on the outlet side, is in free communication with an outlet nozzle of such an internal width and a length such that the internal friction and surface tension of the concentrate in the exhaust stub are sufficient to fix the concentrate column unchanged (check valve on the inlet side closed) and with increasing pump volume (suction stroke) axially unchanged in the exhaust stub to keep. 18. Device according to any one of claims U-17, characterized in that the pump volume is limited by two hollow rigid connecting plugs (1) -2, 1) -3) and one of the opposite ends thereof 3200969-15 - connecting ring pleat (bra) of flexible material, in which a coil spring (48) is arranged in the ring space (47) between the pump volume and the hollow cylindrical housing (40), the ends of which rest against flanges of the turned ends of connection stubs 5 (42 and 43). Device according to claim 18, characterized in that air vents (50) communicating in the annulus with the outer atmosphere open out. 3200969