WO2020030418A1

WO2020030418A1 - Apparatus, system and methods for emitting acoustic energy with circular concave head

Info

Publication number: WO2020030418A1
Application number: PCT/EP2019/069711
Authority: WO
Inventors: Darren Bates
Original assignee: Bubble-tech gmbh
Priority date: 2018-08-06
Filing date: 2019-07-22
Publication date: 2020-02-13
Also published as: EP3829737A1; GB201812759D0

Abstract

An apparatus configured to emit acoustic energy (10). The apparatus comprises a body (26) terminating in an end portion (28). The end portion comprises a concave surface (16) extending from a substantially circular base (20).

Description

TITLE

APPARATUS, SYSTEM AND METHODS FOR EMITTING ACOUSTIC ENERGY WITH CIRCULAR CONCAVE HEAD

TECHNOLOGICAL FIELD

Examples of the disclosure relate to apparatus, systems and methods for emitting acoustic energy, and in particular emitting acoustic energy to at least reduce foaming in applications involving filling, agitating and pouring of liquids, or to induce a controlled amount of foaming.

BACKGROUND

Foam may be generated in applications involving filling, agitating and pouring of liquids, such as in the processing or manufacture of drinks, pharmaceuticals and chemicals. Foam may result from the release and/or excitation of gas from a dissolved state in a liquid into a gaseous state on being disturbed, for instance by filling, agitating or pouring of liquids, and/or being subjected to reduced pressure.

In some applications, the formation of foam is unwanted, since it can hinder the production process and can compromise the product quality. For example, in order to minimize foam formation, the speed at which containers, such as bottles, are filled on a production line may have to be decreased and/or the temperature of the liquid reduced. In each case, the efficiency of the process is reduced. Furthermore, the formation of foam may result in product being lost, and containers being under-filled. There is also a risk of microbiological contamination caused by the foam contacting caps, seals, external sides of the container being filled, and filling equipment. Acoustic energy can be used to reduce foaming in such applications.

In other applications, for example in the filling of containers with beer or cider, the formation of a controlled level of foam is desirable prior to sealing the container, as it displaces oxygen occupying the headspace from the container. This process is known as“fobbing”. Oxygen content in packaged liquids is generally undesirable as it typically leads to product deterioration. Acoustic energy can be used to induce a controlled amount of foaming in such applications. A sonotrode may be used to emit acoustic energy.

There is a requirement to provide apparatus and systems for emitting acoustic energy which are better able to reduce foaming and/or induce a controlled amount of foaming.

The term‘liquid’ is intended to cover any substance that can flow such as liquids and semi-liquids.

BRIEF SUMMARY

According to various, but not necessarily all, examples of the disclosure there is provided an apparatus configured to emit acoustic energy, wherein the apparatus comprises a body terminating in an end portion, wherein the end portion comprises a concave surface extending from a substantially circular base.

The concave surface may be domed shaped. The concave surface may be bell shaped.

The concave surface may be continuous, that is, it may be smooth. Alternatively, the concave surface may be discontinuous, that is, it may be uneven or irregular. The concave surface may comprise a formation. The formation may comprise a concentric rib.

The body may comprise a trunk portion and a neck portion extending from the trunk portion, wherein the neck portion terminates in the end portion. The diameter of the neck portion may be less than the diameter of the circular base of the end portion, and less than the diameter of the trunk portion.

Alternatively, in profile, the body may comprise substantially straight sides which extend to the end portion. The circular base of the end portion may have substantially the same diameter as the trunk portion. Alternatively, the diameter of the circular base of the end portion may be greater than the diameter of the trunk portion.

In profile, the trunk portion may comprise substantially straight sides, and the neck portion may comprise curved sides extending inwardly from the straight sides of the trunk portion and extending outwardly to the circular base of the end portion.

Alternatively, in profile, the trunk portion may comprise substantially straight sides, and the neck portion may comprise substantially straight sides. The substantially straight sides of the neck portion may define the narrowest part of the neck portion, and may extending coaxial to the straight sides of the trunk portion.

The neck portion may comprise, in profile, substantially straight sides extending inwardly from, and inclined relative to, the straight sides of the trunk portion. The neck portion may comprise substantially straight sides extending outwardly from, and at an incline to, the straight sides defining the narrowest part of the neck portion to the circular base of the end portion.

Respective rounded portions, in profile, may define the transition between straight sides, bevelled sides and/or curved sides.

The trunk portion may be substantially cylindrical, cuboid, or rectangular cuboid.

The trunk portion may be configured to be connectable to a transducer for converting an electrical signal to the acoustic energy the apparatus is configured to emit.

The apparatus may comprise a sonotrode.

According to various, but not necessarily all, examples of the disclosure there is provided a system, the system comprising a housing, and an apparatus according to any of the preceding paragraphs, wherein the apparatus is located within the housing, and is spaced from the inner sides of the housing. The housing and the apparatus may have substantially the same length.

The spacing between the apparatus and the inner sides of the housing may be about 0.5 mm to 100 mm, and may be about 1 mm to 50 mm, and may be about 1 mm to 30 mm, and may be about 1 mm to 20 mm, and may be about 2 mm to 20 mm, and may be about 5 mm to 10 mm.

The system may comprise a transducer for converting an electrical signal to acoustic energy, wherein the housing and the apparatus are connected to the transducer.

The housing may comprise an output end, wherein the inner sides of the housing may be configured to focus and intensify the acoustic energy through the output end.

The housing may taper inwardly to provide an output end of reduced relative diameter.

The housing may comprise a tube, and may comprise a pipe. The housing may comprise metal, and may comprise any of: polymers such as plastics, ceramics or glass. The surface of the inner sides of the housing may be a reflective surface configured to reflect acoustic waves, or may comprise a reflective coating.

According to various, but not necessarily all, examples of the disclosure there is provided a system, the system comprising a housing, and an apparatus configured to emit acoustic energy, wherein the apparatus is located within the housing, and is spaced from the inner sides of the housing.

The apparatus may comprise a sonotrode.

The spacing between the apparatus and the inner sides of the housing may be about 0.5 mm to 100 mm, and may be about 1 mm to 50 mm, and may be about 1 mm to 30 mm, and may be about 1 mm to 20 mm, and may be about 2 mm to 20 mm, and may be about 5 mm to 10 mm. The system may comprise a transducer for converting an electrical signal to acoustic energy, wherein the housing and the apparatus are connected to the transducer.

According to various, but not necessarily all, examples of the disclosure there is provided a method comprising providing an apparatus according to the above paragraphs.

According to various, but not necessarily all, examples of the disclosure there is provided a method comprising providing a system according to the above paragraphs.

According to various, but not necessarily all, examples of the disclosure there is provided a method comprising:

emitting acoustic energy from an apparatus according to any of the preceding paragraphs toward a target.

The target may comprise a foam; and the method may comprise reducing the foam bubble size with the emitted acoustic energy; and compressing the foam bubbles with the emitted acoustic energy.

The target may comprise a liquid; and the method may comprise inducing the formation of foam from the liquid with the emitted acoustic energy.

The liquid may comprise beer or cider. The method may comprise emitting acoustic energy from the apparatus to a target when the target is moving on a production line.

emitting acoustic energy from a system according to any of the preceding paragraphs toward a target.

The liquid may comprise beer or cider.

The method may comprise emitting acoustic energy from the system to a target when the target is moving on a production line.

The apparatus, system and methods may comprise any of the features described in any of the preceding statements or following description.

According to various, but not necessarily all, examples of the disclosure there may be provided examples as claimed in the appended claims.

BRIEF DESCRIPTION

For a better understanding of various examples that are useful for understanding the detailed description, reference will now be made by way of example only to the accompanying drawings in which: Fig. 1 illustrates an apparatus;

Fig. 2 illustrates another apparatus;

Fig. 3 illustrates another apparatus;

Fig. 4 illustrates another apparatus;

Fig. 5 illustrates another apparatus;

Fig. 6 illustrates a system;

Fig. 7 illustrates another system;

Fig. 8 illustrates another system; and

Fig. 9 illustrates another system.

DETAILED DESCRIPTION

Figs. 1 to 5 illustrate an apparatus according to examples of the disclosure, and Figs 6 to 9 illustrate a system according to examples of the disclosure.

Figs. 1 to 5 illustrate an apparatus 10 configured to emit acoustic energy. The apparatus 10 comprises a body 12 terminating in an end portion 14. The end portion 14 comprises a concave surface 16 extending from a substantially circular base 18.

The apparatus 10 may comprise a sonotrode. The acoustic energy may comprise ultrasonic energy. The acoustic energy travels in the form of a wave.

The apparatus 10 is configured to focus the acoustic energy toward a target. Focused acoustic energy is energy which is distributed in a focused direction toward the target from the apparatus 10.

The target may be, for instance, the surface of a liquid on which foam has formed or may form. The focused acoustic energy is understood to provide a high acoustic pressure wave on the foam bubble surface, and/or to collapse cavitation bubbles on the foam bubble surface. Accordingly, in use the focused acoustic energy reduces the foam bubble size and compresses the foam bubbles into a dense layer of foam. The use of acoustic energy is non-invasive thereby avoiding microbiological contamination, and leads to little or no loss of liquid. The apparatus 10 may be configured to emit acoustic energy in a controlled manner. In the case of ultrasonic energy (the preferred frequency of acoustic energy being 16kHz to 100kHz), cavitation will be generated by the acoustic wave on the outer surface of each foam bubble. The cavitation bubbles collapse and/or implode releasing localized intensive energy (shear forces) which cause micro-streaming agitation in the liquid causing foam bubbles to be reduced in size, and the foam bubble layer to be compacted into a dense layer.

The apparatus 10 may be configured to emit acoustic energy waves substantially longitudinally and/or substantially diagonally.

Foam bubbles may have an average diameter of about 1 mm to 10mm. The focused acoustic energy may reduce the average diameter of the foam bubbles by about 1 % to about 99%, that is, up to 99%. This has the effect of compressing the foam bubbles into a dense layer of foam.

An example use the apparatus 10 according to examples of the disclosure is the application of acoustic energy to a liquid inside a bottle travelling along a filling or packaging line to reduce the foam bubble size and compress the foam bubbles into a dense layer of foam prior to sealing the bottle. The apparatus 10 may be positioned above the bottles.

In use, the apparatus 10 may be positioned 1 mm to 200mm, and more particularly 1 mm to 50mm from a target, for instance the liquid in the bottles, which defines the distance the acoustic energy emitted from the apparatus 10 must travel before contacting the target. In use, in some examples the acoustic energy would travel through air before contacting the target. The acoustic energy may be emitted substantially uniformly over the distance defined by the separation of the apparatus 10 from the target.

The apparatus 10 may be configured such that the acoustic energy emitted is impedance matched with the air (which may comprise gas originating from the liquid) and foam layer, but not the liquid. Accordingly, in use when the acoustic energy hits the liquid surface, it does not penetrate the liquid but is instead reflected back. Accordingly, in such examples, the acoustic wave would only pass through air (which may comprise gas originating from the liquid) and foam, but not liquids or solids. Emitted acoustic energy may propagate substantially uniformly through volumes of air, gas or foam mediums, to a depth of about 0.0001 to about 300mm, or about 0.001 to about 200mm, or about 0.01 to about 100mm, or about 0.1 to about 75mm, or about 1.0mm to about 50mm, or more particularly about 1 mm to about 10mm.

In some examples of the disclosure, the apparatus 10 is configured to emit acoustic energy at a frequency of about 1 KHz to about 1000KHz, or about 10KHz to about 500KHz, or about 10KHz to about 250KHz, or about 10KHz to about 125KHz, or about 10KHz to about 100KHz, or about 10KHz to about 50KHz, or about 15KHz to about 35KHz, or about 16KHz to about 30KHz, or about 16KHz to about 25KHz, or about 16KHz to about 20KHz.

In some examples of the disclosure, the apparatus 10 is configured to emit acoustic energy at an amplitude of about 0.001 to about 1000microns, or about 0.001 to about 500microns, or about 0.1 to about 500microns, or about 1 micron to about 500microns, or about 10 to about 500microns, or about 100 to about 500microns, or about 151 microns to about 500microns, or about 151 to about 400microns, or about 151 microns to about 300micron, or about 151 microns to about 250microns, or about 151 microns to about 200 microns peak to peak displacement.

In some examples of the disclosure, the apparatus 10 is configured to emit acoustic energy at an energy intensity of about 0.001 W/cm² to about 500W/cm², or about 0.01 W/cm² to about 400W/cm², or about 0.1 W/cm² to about 300W/cm², or about 1 W/cm² to about 200W/cm², or about 1 W/cm² to about 100W/cm², or about 1 W/cm² to about 50W/cm², or about 1W/cm² to about 20W/cm², or about 1W/cm² to about 10W/cm².

In examples of the disclosure, the liquid may include, but is not limited to: a beverage, beer, cider, juices, tea, alcoholic mixers, spirits, dairy mixers/smoothies, energy drinks, coffee, vegetable based liquids, sauces, animal based stocks, vegetable based stocks, wine, milk, cleaning chemicals, health care products, pharmaceutical liquids, detergents, paint, lacquers, oil, fertilizers. In the illustrated example, the concave surface 16 is domed shaped or bell shaped. Accordingly, the substantially circular base 18 is indented, and has an inward circular curvature defining the concave surface 16. The indentation is therefore rounded. In some examples, a rim 20 is provided on the substantially circular base 18. The rim 20 defines an area of the substantially circular base 18 which is not indented. The apparatus 10 may comprise a vibrating surface configured to emit acoustic energy.

In the example illustrated in Fig. 1 , the concave surface 16 is continuous, that is, it is smooth. Accordingly, the concave surface 16 is not uneven or irregular.

In other examples, the concave surface 16 may be discontinuous, that is, it may be an uneven or irregular.

In other examples, for instance, as illustrated in Fig. 2, the concave surface 16 may comprise a formation 22. The formation 22 may be regular, that is, it may be arranged in, or constituting, a constant or definite pattern. In the illustrated example, the formation 22 comprises a concentric rib 24, that is, a rib 24 in the form of a concentric ring. The concave surface 16 may comprise a plurality of concentric ribs 24. Accordingly, the concave surface 16 may comprise at least one rib 24, and may comprise a plurality of ribs 24. The rib 24 or ribs 24 may be concentric, or may have a different arrangement. In such examples, the concave surface 16 is ribbed. A ribbed surface enables a higher acoustic intensity (greater than 151 microns amplitude).

In the examples illustrated in Figs. 1 , 2, 4 and 5, the body 12 comprises a trunk portion 26 and a neck portion 28 extending from the trunk portion 26, wherein the neck portion 28 terminates in the end portion 14. The diameter of the neck portion 28 is less than the diameter of the circular base 18 of the end portion 14, and less than the diameter of the trunk portion 26.

In the example illustrated in Fig. 3, in profile, the body 12 comprises substantially straight sides 30 which extend to the end portion 14. Accordingly, in this example the body 12 is continuous, that is, the trunk portion 26 extends to, and terminates in, the end portion 14. The apparatus 10 of Fig. 3 does not therefore comprise a neck portion 16. In the examples illustrated in Figs. 1 , 2, 3, and 5, the circular base 18 of the end portion 14 has substantially the same diameter as the trunk portion 26.

In the example illustrated in Fig. 4, the diameter of the substantially circular base 18 of the end portion 14 is greater than the diameter of the trunk portion 26. The increased diameter of the substantially circular base 18, in use, leads to focused acoustic energy being emitted over a greater surface area of the target.

The diameter of the substantially circular base 18 may be about 20mm to about 200mm.

In the examples illustrated in Figs. 1 , 2, and 4, in profile, the trunk portion 26 comprise substantially straight sides 32, and the neck portion 28 comprise curved sides 34 extending inwardly from the straight sides 32 of the trunk portion 26 and extending outwardly to the circular base 18 of the end portion 14.

In the example illustrated in Fig. 5, in profile, the trunk portion comprises substantially straight sides 32, and the neck portion comprises substantially straight sides 36. The substantially straight sides 36 define the narrowest part of the neck portion 28, and extend coaxial to the straight sides 32 of the trunk portion 26.

In the illustrated example, in profile, the neck portion 28 comprises substantially straight sides 38 extending inwardly from, and inclined relative to, the straight sides 32 of the trunk portion 26, that is, bevelled sides 38. In this example, the neck portion also comprises substantially straight sides 40 extending outwardly from, and at an incline to, the straight sides 36 defining the narrowest part of the neck portion 28 to the circular base 18 of the end portion 40, that is, bevelled sides 40.

As illustrated in Figs. 1 and 5, respective rounded portions 42, in profile, may define the transition between straight sides 32, 36, bevelled sides 38, 40 and/or curved sides 34.

The trunk portion 26 may be substantially cylindrical, cuboid, or rectangular cuboid. The trunk portion 26 may have a block shape. With respect to the curvature defining the concave surface 16 and the neck portion 28, the greater the curvature angle, the more focused and more intensive is the acoustic wave emitted. The curvature angle can be relatively small (1 degree to 25 degrees) or relatively large (25 degrees to 45 degrees). Furthermore, the smaller the radius of the concave surface 16 and the neck portion 28, the more focused and more intensive is the acoustic energy wave emitted. The radius can vary from 10mm to 100mm.

The apparatus 10 illustrated in Fig. 1 has the greatest curvature angle and smallest radius of the illustrated apparatus 10. The radius of the curvature defining each of the concave surface 16 and the neck portion 28 is 10mm. The apparatus provides a relatively high acoustic intensity of 195microns amplitude, but over a relatively small footprint area (surface area) of 20mm x 20mm.

The apparatus 10 illustrated in Fig. 4 has a smaller curvature angle than the apparatus of Fig. 1 , but the radius of curvature is larger. The radius of curvature defining each of the concave surface 16 and the neck portion 28 is 100mm. Accordingly, the apparatus provides a lower acoustic intensity of 151 microns amplitude, but over a wider footprint area of 200mm x 200mm.

In some examples, the apparatus 10 may comprise titanium, or an alloy thereof (such as nickel titanium alloy), hastalloy, stainless steel, aluminium, or ceramic. Accordingly, the apparatus 10 may be formed from such materials, or combinations of such materials. The apparatus may comprise a protective coating, such as Polytetrafluoroethylene (PTFE), to protect the apparatus 10 from cleaning chemicals. The thickness of the protective coating may be about 0.001 mm to 10mm. A coating thickness in this range would allow sufficient acoustic energy to transmit through the coating.

In examples according to the invention, the trunk portion 26 is configured to be connectable to a transducer (not illustrated in Figs. 1 to 5). The transducer is connectable to a generator. A transducer transforms electrical energy from the generator into vibrational (oscillatory) energy, which generates acoustic energy. An alternating voltage may be applied across a ceramic, or piezoelectric crystalline material (PZT), or a magnetostrictive material (such as a Terfenol-D magnetostrictive material or a Nickel/lron/Vanadium magnetostrictive material) of the transducer. The vibrational energy may be delivered directly to the air/gas/foam medium container via the apparatus 10, or optionally via a booster unit (not illustrated). A PZT transducer may be mechanically coupled to the apparatus 10, wherein the apparatus 10 amplifies the motion of the PZT (piezo ceramic transducer) and the acoustic energy wave.

Examples of the disclosure also provide a system 100, as illustrated in Figs. 6 and 7.

The system 100 comprises a housing 102, and an apparatus 10 according to examples of the disclosure. The apparatus 10 is located within the housing 102, and is spaced from the inner side 104 of the housing 102.

The spacing between the apparatus 10 and the inner side 104 of the housing 102 may be about 0.5 mm to 100 mm, and may be about 1 mm to 50 mm, and may be about 1 mm to 30 mm, and may be about 1 mm to 20 mm, and may be about 2 mm to 20 mm, and may be about 5 mm to 10 mm.

The system 100 may comprise a transducer 106 for converting an electrical signal to acoustic energy. In some example, the housing 102 and the apparatus 10 are connected to the transducer 106. Accordingly, the housing 102 may also transfer some of the energy directly from the transducer 106. Advantageously, in such examples the housing 102 not only reflects and intensifies the acoustic energy of the apparatus 10, but also acts as a sonotrode in its own right, and therefore provides an enhanced performance.

The housing 102 may be connected to the transducer via a spacer and therefore ultrasonic waves transmit down the housing 102 surface.

The transducer 106 is connectable to a generator (not illustrated). The housing 102 may comprise a tube, and may comprise a pipe. The housing 102 may be a resonating tube or pipe. The housing 102 may comprise metal such as stainless steel, and may comprise any of: polymers such as plastics, PTFE, ceramics or glass, or combinations thereof.

The surface of the inner side 104 of the housing 102 may be a reflective surface configured to reflect acoustic waves, or may comprise a reflective coating. The housing 102, which may be for instance a metal pipe, may be resonating acoustic pipe.

The housing 102 may comprise an output end 108. The inner side 104 of the housing 102 is configured to focus and intensify the acoustic energy through the output end 108 as illustrated by the arrows. The acoustic waves are reflected by the inner side 104 of the housing toward the output end 108. The acoustic energy is therefore emitted substantially from the base of the housing 102.

In some examples, the housing 102 may taper inwardly to provide an output end 108 of reduced relative diameter. The inward taper may be curved or straight sided. In some examples, the housing 102 may be substantially bottled-shaped to provide an output end 108 of reduced relative diameter. In other examples, the housing 102 may be cone-shaped to provide an output end 108 of reduced relative diameter. Advantageously, acoustic energy emitted from an output end 108 of reduced relative diameter is more focused and at a higher intensity.

In some examples, the length of the housing 102 is substantially the same as the length of the apparatus 10, as illustrated in Figs. 6 and 7. The internal length of the housing 102 may be substantially the same as the external length of the apparatus 10. The housing 102 may also be x number of half wavelengths (which could be 2, 3 or 4) which is directly proportional to the frequency of the apparatus 10. In such examples, each half wavelength is 125mm in length and so the total length for 2 half wavelengths would be 250mm, and for 3 half wavelengths would 375mm.

The acoustic energy transmitted from the apparatus 10 in both a longitudinal and orthogonal direction is reflected and concentrated by the inner side 104 of the housing, focusing the energy in a longitudinal downward direction to the output end 108. The acoustic energy emitted from the output end 108 of the housing 102 is at a higher acoustic intensity than the acoustic energy emitted from apparatus 10, thereby reducing the foam bubble size and compressing the foam bubbles into a dense layer of foam to a greater extent than the apparatus 10, that is, the apparatus 10 alone. This leads to further performance improvements, for instance on the packaging/filling line, such as increased filling speed, reduced package rejects, more product retained in the package, less spillage and foam losses from the package, less contamination on the package and seals, greater ability to increase temperature of the liquid in the package and increased capability to inject more carbon dioxide or nitrogen in the head space of the package before sealing.

The acoustic energy emitted may be controlled such that liquid will not rise to the top of the bottle and overflow before a seal is applied, ensuring that no product or liquid loss occurs.

Furthermore, as the acoustic energy emitted from the output end 108 of the housing 102 is at a relatively higher acoustic intensity (for instance, than the apparatus 10 alone), the distance over which the acoustic energy can effectively reduce foam is increased, that is, the output end 108 could be positioned further away from the target. In some examples the output end 108 could be positioned at least twice the distance from the target compared to the apparatus 10 alone. Furthermore, the surface area covered by the acoustic energy is greater. The surface area may be at least twice that of the surface area covered by the apparatus 10 alone. The surface area covered may be defined by the diameter of the output end 108.

In use, the resonating housing 102, for example pipe, may be positioned with respect to a target in a vertical orientation, diagonal orientation at any angle between 10 and 89 degrees, or in a horizontal orientation to compress the foam and reduce foam bubble size.

The distance the output end 108 can be held from a target may be any of: 200mm, 100mm, 50mm, 40mm, 30mm, 20mm, or about 1 mm to 20mm.

In some examples, the output end 108 may be of a reduced diameter relative to the reminder of the housing 102. Fig. 7 illustrates an example system 100 wherein the output end 108 opens into conduit 1 10 through which liquid flows.

The apparatus 10 and system 100 could be used in conjunction with various large and small scale applications involving filling, agitating and/or pouring liquids. The apparatus 10 or system 100 could be provided in conjunction with flow chambers, tanks, vessels, pipes, open flumes, open tanks, ponds, various packaging process (for example bottles, cans, pouches, cartons), automated filling lines. The foam could be found in any type of packaging process (bottles, cans, pouches, cartons) during the filling process of liquids (chemicals, health care products, cosmetics, beverages, dairy such as milk, beer, cider, carbonated liquids such as soft drinks, alcoholic mixers, wine).

Such applications may use a one of an apparatus 10 or system 100, or may use a plurality of apparatus 10 and/or systems 100.

Apparatus 10 and systems 100 according to the invention may also comprise, or operate in conjunctions with, automatic resonance frequency tracking. Accordingly, during use of the apparatus 10 and system 100 a controller is continually scanning for new resonance frequencies (relates to maximum power output) due to changes in the equipment, process conditions and changes in the liquid (including bubble formation). Resonance frequency tracking may re-scan for new resonance frequencies every 0.001 second throughout the foaming process. Without resonance frequency tracking a variation as little as 1 KHz from the resonance frequency may result in a drop in energy efficiency in the order of 10% to 90% which may have an adverse effect on the efficiency of energy transmission. Resonance frequency tracking allows for constant and uniform vibration and energy distribution.

The figures also illustrate a method comprising providing an apparatus 10 according to examples of the disclosure. The figures also illustrate a method comprising providing a system 100 according to examples of the disclosure.

The figures also illustrate a method comprising: emitting acoustic energy from an apparatus 10 according to any of the preceding paragraphs toward a target, wherein the target comprises a foam; reducing the foam bubble size with the emitted acoustic energy; and compressing the foam bubbles with the emitted acoustic energy. The target may comprise a liquid. The target may be moving on a production line.

The figures also illustrate a method comprising: emitting acoustic energy from a system 100 according to any of the preceding paragraphs toward a target, wherein the target comprises a foam; reducing the foam bubble size with the emitted acoustic energy; and compressing the foam bubbles with the emitted acoustic energy.

The target may comprise a liquid. The target may be moving on a production line.

The apparatus 10 and systems 100 according to example of the disclosure may also be used to apply acoustic energy to induce gas release into liquids, for example beer and cider, and thus induce fobbing, in a controlled manner, for displacing headspace from containers such as bottles comprising the liquid. In such examples, the apparatus 10 or system 100 may be in direct contact with containers, for instance moving along a packaging line, or may be spaced a distance from the containers, for instance from the side of the containers. In examples in which there is direct contact, the contact may be with the side or base of the containers. In high throughput applications, where hundreds, if not thousands of containers, such as bottles, need to be fobbed per hour, and bottles of different sizes need to be processed on the same automated line, a coupling medium, such as a liquid, may be used between the apparatus 10 or systems 100 and the containers to further improve transmission of acoustic energy into the liquid within the container.

The apparatus 10 systems 100 can also be used for displacing headspace from a container that has undergone the sealing process but in which the seal is faulty (there will be very little or no displacement if the seal is intact). Advantageously, this allows detection of any faulty or failed seals in containers after the sealing stage in packaging. If a faulty seal is present in a‘sealed’ container, fobbing of the contents will result in pushing of headspace and typically liquid phase (foam and/or liquid) through the faulty seal due to the increase in volume of the liquid phase, thus allowing detection of faulty or failed seals. As illustrated in Fig. 8, acoustic energy may be emitted to the base of bottles 1 18 to induce fobbing. In such examples, a substantially horizontal plate 1 12 (illustrated in side view) may be attached to the output end 108 of the housing 102 of a system 100 according to examples of the disclosure. In use, acoustic energy emitted from the system 100 induces the formation of foam from the liquid (that is, induces fobbing) in the bottles to a controlled extent as the bottles pass over the substantially horizontal plate 1 12 (note the increased level of foam in the bottle downstream of the system 100). The direction of travel of the bottles is indicated by arrows 1 16.

As illustrated in Fig. 9, acoustic energy may be emitted to the side of bottles 1 18 to induce fobbing. In such examples, a curved plate 1 14 (illustrated in plan view) may be attached to the output end 108 of the housing 102 of a system 100 according to examples of the disclosure. In use, acoustic energy emitted from the system 100 induces the formation of foam from the liquid (that is, induces fobbing) in the bottles to a controlled extent as the bottles pass by the curved plate 1 14. In use, the sides of the bottles may touch the side of the curved plate 1 14 as they pass between filler and capper. In other examples, the bottles may not be in contact with the curved plate 1 14. The direction of travel of the bottles is indicated by arrows 1 16.

Although bottles are illustrated in Figs. 8 and 9, any other type of container or package may be accommodated.

The substantially horizontal plate 1 12 and the curved plate 1 14 are fobbing plates. Fobbing plates may be 10 to 4000 mm in length.

With respect to the examples of Figs. 8 and 9, the performance of fobbing can be further improved by having a coupling liquid on the fobbing plate 1 12, 1 14 or between the bottle and the fobbing plate 1 12, 1 14. The coupling liquid may be water, but it could also be any type of liquid including oils, liquid polymers, aqueous based and none aqueous based.

In use, fobbing plates 1 12, 1 14 may be in contact with the bottles or spaced from the bottles, that is, not in contact with the bottles. Examples

Apparatus 10 and systems 100 according to examples of the disclosure may be used in conjunction with an automated line in a factory, wherein the line is configured to accommodate containers of different sizes, for instance different girths. The apparatus 10 or system 100 may be configured such that the acoustic energy emitted is impedance matched with the air so that the acoustic wave can travel or be transmitted through an air space of between 1 mm to 200mm and still create sufficient intensity to reduce the foam bubble size and compact the foam bubbles into a dense compacted layer of foam in containers moving along the line.

The apparatus 10 or system 100 may be positioned vertically above, diagonally above, to the side, or horizontally to the side of the containers moving along the line. Accordingly, acoustic energy can be applied after the container has been filled, or during the filling of the container. The container may be in any type of automated packaging line (aseptic, none aseptic, explosion proof, hot-fill), and may be any suitable sealable container. For example, the container may be a glass bottle, a plastic bottle (such as a PET bottle), a can, a pouch, or a cardboard carton (such as a wax- coated cardboard carton), metal container, any type of plastic container. The size of the package can vary from 5ml volume up to 100 liter volume size. The speed of the packaging line containers can vary from 100 containers per hour up to 150,000 containers per hour.

The apparatus 10 or system 100 may be positioned on a line so that acoustic energy can be emitted to a liquid before containers are sealed.

In the case of beer and cider can lines, the apparatus 10 or system 100 is preferably positioned proximal to, that is, close to a seamer (sealer) entrance, for example within 1000mm to the seamer entrance. This is because if the foam compression and bubble size reduction is conducted at an earlier point on the line between the filler and seamer, there is a possibility and risk that oxygen could penetrate into the head space resulting from foam compression, which could cause problems in quality for the beer and cider. Furthermore, the preferred position is up to 500mm from a high pressure water injector on a star wheel of a beer bottling line. Furthermore, the apparatus 10 or system 100 and the high pressure water device should be as close as possible to the filler section of the packaging line. Accordingly, when the hot water injector is applied, the dense layer and small bubbles are retained when the beer foam is expanded/grows/fobbed to push out the oxygen. Due to the dense foam layer and small bubbles, more oxygen is pushed out of the head space in the bottle but in a controlled manor with little or no over-foaming, resulting in improved efficiency of the packaging line (less beer losses, less container rejects, less contamination on the seal/caps).

For beer lines using a carbon dioxide doser, the apparatus 10 or system 100 may be positioned preferably up to 500mm from the carbon dioxide doser. By compressing the foam into dense layer of smaller bubbles allows for more carbon dioxide to be dosed and higher pressure of carbon dioxide in the capped/sealed container. Higher C02 content into the head space of the container will mean more oxygen displaced resulting in improved quality and shelf-life of the beer.

For beverage lines using a nitrogen doser (juice, tea, flavored water, soft drink beverages), the apparatus 10 or system 100 may be positioned preferably up to 500mm from the nitrogen doser. By compressing the foam into dense layer of smaller bubbles allows for more nitrogen to be dosed and higher pressure of nitrogen in the capped/sealed container. Higher nitrogen content into the head space of the container will mean more oxygen displaced resulting in improved quality and shelf-life of the beverage.

For packaging lines in general like carbonated soft drinks, dairy/milk, none- carbonated beverages, chemicals, health-care products, pharmaceutical products, the apparatus 10 or system 100 should be positioned on the star wheel or conveyor at a point where the foam is close to over foaming out of the container. By applying the acoustic energy just before over-foaming will mean that the liquid product is reduced in bubble size and compressed down back into the container preventing any liquid foam losses.

In some example, the acoustic energy may be applied to a container containing a liquid over a period of time from about 0.0001 second to about 30 minutes, or from about 0.001 second to about 1 minute, or from about 0.001 seconds to about 30 seconds, or from about 0.001 seconds to about 10 seconds, or from about 0.001 seconds to about 9 seconds, or from about 0.001 seconds to about 8 seconds, or from about 0.001 seconds to about 5 seconds, or about 0.5 seconds, or about 1 second, or about 2 seconds, or about 3 seconds, or about 4 seconds, or about 5 seconds, or about 6 seconds, or about 7 seconds, or about 8 seconds, or about 10 seconds.

Accordingly, the length of exposure of containers to the acoustic energy and/or the intensity of the acoustic energy can be readily adjusted to regulate the extent of the foam compression (which may be monitored by electronic optical means, which may also be integrated with a feedback mechanism to the power/signal control for the apparatus 10 or system 100.

In examples according to the disclosure, apparatus 10 and systems 100 may be positioned along a filling or packaging line downstream of a filling carrousel between a filler and capper, and may be positioned on the carrousel filler. In such examples, the apparatus 10 and/or systems 100 may be positioned above the top of the container, and may be positioned 1 mm, or 2mm, or 3mm, or up to 5mm, or up to 10mm, or up to 20mm, or up to 30mm, or up to 40mm, or up to 50mm, or up to 100mm, or up to 200mm above the top of the container.

Apparatus 10 and systems 100 may be mounted or retrofitted to filling or packaging lines.

Although there are many known different types and/or configurations of filling/ packaging lines for liquids, apparatus 10 and systems 100 according to the present disclosure may be readily fitted or retrofitted to any known filling or packaging line. For example, an apparatus 10 and systems 100 could be retro-fitted into any part of a star wheel section of a typical factory filling line. The star wheel section is a circular rotating transfer section between a filler carousel and a capper. The star wheel section can vary in size depending on the type of filling line.

Filling or packaging systems may be, for example, rotary or linear filling lines for cans, bottles and pouches, or may be multi-filling valve index filling machines for pouches and cartons. Packaging lines can vary in speed from 150,000 containers per hour to 10 containers per hour. Container size can vary from 5ml up to 500 liters. The material of the container can be any suitable material, such as metal, glass, plastic, cardboard or aluminum.

Effect of amplitude and duration of acoustic exposure on foam bubble size reduction and foam compaction efficiency Example 1

20kHz frequency

150 micron amplitude peak to peak displacement

33cl bottle size of lager beer

Exposure time of bottle on star wheel

30,000 bottles per hour speed - 70% of foam in neck of bottle compacted, bubble size reduced from 2mm to 0.15mm

40,000 bottles per hour - 55% of foam in neck of bottle compacted, bubble size reduced from 2mm to 0.5mm

50,000 bottles per hour - 40% of foam in neck of bottle compacted, bubble size reduced from 2mm to 0.8mm

Example 2

20kHz frequency

160 micron amplitude peak to peak displacement

33cl bottle size of lager beer

Exposure time of bottle on star wheel

30,000 bottles per hour speed - 80% of foam in neck of bottle compacted, bubble size reduced from 2mm to 0.1 mm

40,000 bottles per hour - 65% of foam in neck of bottle compacted, bubble size reduced from 2mm to 0.35mm

50,000 bottles per hour - 50% of foam in neck of bottle compacted, bubble size reduced from 2mm to 0.45mm

Example 3

20kHz frequency

170 micron amplitude peak to peak displacement

33cl bottle size of lager beer

Exposure time of bottle on star wheel 30,000 bottles per hour speed - 90% of foam in neck of bottle compacted, bubble size reduced from 2mm to 0.05mm

40,000 bottles per hour - 70% of foam in neck of bottle compacted, bubble size reduced from 2mm to 0.2mm

50,000bottles per hour- 60% of foam in neck of bottle compacted, bubble size reduced from 2mm to 0.35mm

Foam bubble size: between 1 mm and 5mm diameter

Example 4

30kHz frequency

150 micron amplitude peak to peak displacement

33ml bottle size of lager beer

10,000 bottles per hour - 65% of foam in neck of bottle compacted, bubble size reduced from 2mm to 0.25mm

20,000 bottles per hour - 50% of foam in neck of bottle compacted, bubble size reduced from 2mm to 0.4mm

30,000 bottles per hour - 40% of foam in neck of bottle compacted, bubble size reduced from 2mm to 0.55mm

Example 5

30kHz frequency

160 micron amplitude peak to peak displacement

33ml bottle size of lager beer

10,000 bottles per hour - 75% of foam in neck of bottle compacted, bubble size reduced from 2mm to 0.15mm

20,000 bottles per hour - 60% of foam in neck of bottle compacted, bubble size reduced from 2mm to 0.25mm 30,000 bottles per hour - 50% of foam in neck of bottle compacted, bubble size reduced from 2mm to 0.35mm

Example 6

30kHz frequency

170micron amplitude peak to peak displacement

33ml bottle size of lager beer

10,000 bottles per hour - 85% of foam in neck of bottle compacted, bubble size reduced from 2mm to 0.05mm

20,000bottles per hour- 70% of foam in neck of bottle compacted, bubble size reduced from 2mm to 0.1 mm

30,000bottles per hour- 60% of foam in neck of bottle compacted, bubble size reduced from 2mm to 0.15mm Table 1 - Effectiveness of foam compaction of liquid-filled bottles comparing the apparatus 10 of Fig. 1 with the system 100 of Fig. 6

Table 2 - Effect of acoustic energy frequency on beer bubble size and headspace oxygen levels

Accordingly, the frequency of the acoustic waves impacts the size of the cavitation bubbles created and the resulting micro-streaming effect; the higher the frequency, the smaller the bubble diameter, and the smaller the micro-streaming effects. Accordingly, the higher the frequency of the acoustic energy used, the smaller the bubbles/foaming that are formed in the compacted foam layer in the container. The smaller the bubble foam size means the higher the surface area of the bubble. A smaller bubble size and higher surface area means that the contact with the oxygen/air in the head space is greater, and this results in greater efficiency of removal of oxygen in the head space of the container and the foam layer is denser with smaller bubbles, so the heavier/denser layer is more likely to be retained in the container during the high speed sealing process. As an example of the increased efficiency of headspace removal, at 20kHz the oxygen level in the head space after foaming is 38 ppb and reduced losses of 0.3%, and at 35kHz the oxygen level in the head space afterfoaming is 29 ppb and reduced losses of 0.45%. There is thus described an apparatus, system and method with a number of advantages as detailed above and as follows. In use the configuration of apparatus 10 and systems 100 according to examples of the disclosure provide focused acoustic energy which reduces foam bubble size and compresses foam bubbles into a dense layer of foam. Accordingly, the apparatus 10 and systems 100 are better able to reduce and/or control foaming, and thus provide a solution to the problems described above.

For instance, apparatus 10 and systems 100 according to examples of the disclosure may increase the filling speed of the packaging line by 1 % up to 50%, that is, up to 50%, and reduce product losses from a container by 0.01 % to 5%, that is, up to 5%. For instance, apparatus 10 and systems 100 according to examples of the disclosure may reduce the container rejects by up to 99% resulting from under-fills due to excessive over foaming losses, and reduce or eliminate contamination on the cap, seal, side of container, filling line equipment. For instance, apparatus 10 and systems 100 according to examples of the disclosure may allow the temperature of the liquid to be increased during the filling process by reducing or turning off the chillers. The temperature could be increased by about 1 °C to 10°C, that is, up to 10°C thereby reducing energy consumption as the liquid does not need to be cooled as much. Increasing the temperature may eliminate condensation on packaging materials, which eliminates or reduces quality problems on packaging, and eliminate labeling issues on the labeling machine.

For instance, apparatus 10 and systems 100 according to examples of the disclosure may reduce the amount of anti-foaming chemicals used in a container or tank, and increase the head space availability in a tank or container.

For instance, apparatus 10 and systems 100 according to examples of the disclosure may improve the efficiency of nitrogen or carbon dioxide dosing systems to displace oxygen from liquids and increase nitrogen or carbon dioxide pressure in the capped container by about 1 % to 40%, that is, up to 40%. Furthermore, apparatus 10 and systems 100 according to examples of the disclosure may be configured such that the emitted acoustic energy pushes out more oxygen (up to 90%) from the head space of the container, and therefore eliminates the need for carbon dioxide dosing systems, for instance on beer packaging lines. Such dosing system may introduce microbiological contamination. Apparatus 10 according to examples of the disclosure are configured, that is, shaped, to intensify and focus emitted acoustic energy. The system 100, for example in which the apparatus 10 may be housed in a resonating pipe or tube, may intensify and focus emitted acoustic energy to an even greater extent, that is, relative to the apparatus alone.

Although embodiments of the present invention have been described in the preceding paragraphs with reference to various examples, it should be appreciated that modifications to the examples given can be made without departing from the scope of the invention as claimed. For example, apparatus, systems and methods according to the invention can be applied to the reduction and/or control of foaming with respect to liquids in containers which have already been sealed, for example, to monitor fill height, fill volume, and detect faulty seals. Apparatus 10 and system 100 according to examples of the disclosure may be configured to emit acoustic energy axially or radially.

The curvature angle of the concave surface 16 of the apparatus 10 may be selected according to the intended use of the apparatus 10. For example, the curvature angle of the concave surface 16 may be selected according to the neck diameter of a container (bottle or can) of a packaging filling line. The dimensions of the apparatus 10 may also be selected according to a particular frequency required. For high speed packaging lines (40,000 to 120,000 containers per hour) a larger dimension (the substantially circular base 18 would have a diameter of about 20mm to 100mm) would be selected (frequency of about 16kHz to 25kHz). For lower speed packaging lines (500-39,000 containers per hour, a smaller dimension (the substantially circular base 18 would have a diameter of about 20mm to 80mm) would be selected (frequency 20kHz-60kHz).

Examples according to the disclosure may comprise a plurality of apparatus 10 and/or systems 100 according to the invention, that is, an array of apparatus 10 and/or systems 100 may be provided.

Features described in the preceding description may be used in combinations other than the combinations explicitly described. Although functions have been described with reference to certain features, those functions may be performable by other features whether described or not.

Although features have been described with reference to certain embodiments, those features may also be present in other embodiments whether described or not.

The term“comprise” is used in this document with an inclusive not an exclusive meaning. That is any reference to X comprising Y indicates that X may comprise only one Y or may comprise more than one Y. If it is intended to use“comprise” with an exclusive meaning then it will be made clear in the context by referring to“comprising only one...” or by using“consisting”.

In this brief description, reference has been made to various examples. The description of features or functions in relation to an example indicates that those features or functions are present in that example. The use of the term“example” or“for example” or“may” in the text denotes, whether explicitly stated or not, that such features or functions are present in at least the described example, whether described as an example or not, and that they can be, but are not necessarily, present in some of or all other examples. Thus“example”,“for example” or“may” refers to a particular instance in a class of examples. A property of the instance can be a property of only that instance or a property of the class or a property of a sub-class of the class that comprise some but not all of the instances in the class. It is therefore implicitly disclosed that a features described with reference to one example but not with reference to another example, can where possible be used in that other example but does not necessarily have to be used in that other example.

Whilst endeavoring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.

Claims

1. An apparatus configured to emit acoustic energy, wherein the apparatus comprises a body terminating in an end portion, wherein the end portion comprises a concave surface extending from a substantially circular base.

2. An apparatus according to claim 1 , wherein the concave surface comprises a formation, wherein the formation comprises a concentric rib.

3. An apparatus according to claims 1 or 2, wherein the body comprises a trunk portion and a neck portion extending from the trunk portion, wherein the neck portion terminates in the end portion.

4. An apparatus according to claim 3, wherein the diameter of the neck portion is less than the diameter of the circular base of the end portion, and less than the diameter of the trunk portion.

5. An apparatus according to claims 3 or 4, wherein the circular base of the end portion has substantially the same diameter as the trunk portion.

6. An apparatus according to any of claims 3 or 4, wherein the diameter of the circular base of the end portion is greater than the diameter of the trunk portion.

7. An apparatus according to claims 1 or 2, wherein, in profile, the body comprises substantially straight sides which extend to the end portion.

8. An apparatus according to claims 2 or 7, wherein the trunk portion is substantially cylindrical, cuboid, or rectangular cuboid.

9. A method comprising:

emitting acoustic energy from an apparatus according to any of claims 1 to 8 toward a target.

10. A method according to claim 9, wherein the target comprises a foam; and the method comprises: reducing the foam bubble size with the emitted acoustic energy; and compressing the foam bubbles with the emitted acoustic energy.

1 1 . A method according to claim 9, wherein the target comprises a liquid; and the method comprises:

inducing the formation of foam from the liquid with the emitted acoustic energy.

12. A method according to claim 1 1 , wherein the liquid comprises beer or cider.

13. A method according to any of claims 9 to 12, wherein the method comprises emitting acoustic energy from the apparatus to a target when the target is moving on a production line.

14. A system, the system comprising a housing, and an apparatus according to any of claims 1 to 8, wherein the apparatus is located within the housing, and is spaced from the inner sides of the housing.

15. A system according to claim 14, wherein the spacing between the apparatus and the inner sides of the housing is about 0.5 mm to 100 mm.

16. A system according to claims 14 or 15, wherein the spacing between the apparatus and the inner sides of the housing is about 1 mm to 50 mm.

17. A system according to any of claims 14 to 16, wherein the spacing between the apparatus and the inner sides of the housing is about 1 mm to 30 mm.

18. A system according to any of claims 14 to 17, wherein the spacing between the apparatus and the inner sides of the housing is about 1 mm to 20 mm.

19. A system according to any of claims 14 to 18, wherein the spacing between the apparatus and the inner sides of the housing is about 2 mm to 20 mm.

20. A system according to any of claims 14 to 19, wherein the spacing between the apparatus and the inner sides of the housing is about 5 mm to 10 mm.

21. A system according to any of claims 14 to 20, wherein the system comprises a transducer for converting an electrical signal to acoustic energy, wherein the housing and the apparatus are connected to the transducer.

22. A system according to claim 21 , wherein the housing comprises an output end, wherein the inner sides of the housing are configured to focus and intensify the acoustic energy through the output end.

23. A system according to claim 22, wherein the housing tapers inwardly to provide an output end of reduced relative diameter.

24. A system according to claims 21 or 22, wherein the surface of the inner sides of the housing is a reflective surface configured to reflect acoustic waves.

25. A method comprising:

emitting acoustic energy from a system according to any of claims 14 to 24 toward a target.

26. A method according to claim 25, wherein the target comprises a foam; and the method comprises:

reducing the foam bubble size with the emitted acoustic energy; and compressing the foam bubbles with the emitted acoustic energy.

27. A method according to claim 25, wherein the target comprises a liquid; and the method comprises:

28. A method according to claim 27, wherein the liquid comprises beer or cider.

29. A method according to any of claims 25 to 28, wherein the method comprises emitting acoustic energy from the system to a target when the target is moving on a production line.