GB2447579A

GB2447579A - Beverage foaming apparatus

Info

Publication number: GB2447579A
Application number: GB0810620A
Authority: GB
Inventors: Stuart Clark; Thomas Leech; George Walters
Original assignee: Morphy Richards Ltd; Morphy Richards NI Ltd
Current assignee: Morphy Richards Ltd; Morphy Richards NI Ltd
Priority date: 2006-05-31
Filing date: 2006-05-31
Publication date: 2008-09-17
Anticipated expiration: 2026-05-31
Also published as: GB2438596A; GB0610869D0; GB2447579B; GB2438596B; GB0810620D0

Abstract

Beverage foaming apparatus having a paddle rotatably mounted at an axle capable of being suspended from a coffee maker. The paddle and axle are shrouded by a housing 101 , the housing having windows covered by a gauze or mesh. The housing is suspended from the coffee maker over and about the rotatable paddle whereby the paddle is capable of rotation within the housing adjacent to the mesh covered windows. In use, as the paddle and housing are submerged within the liquid beverage, the paddle by rotation within the housing, forces liquid through the mesh covered windows creating very fine air bubbles so as to generate a fine beverage foam. The housing further comprises at least one exhaust port 107 in said housing above the liquid level in use and a port portion submerged in said liquid.

Description

BEVERAGE FOAMING APPARATUS

Field of the Invention

The present invention relates to beverage foaming apparatus and in particular, although not exclusively, to apparatus for frothing beverages such as milk.

Background to the Invention

For the creation of foamy, frothed beverages, two distinct types of frothing apparatus have emerged. A first type of foaming device utilizes steam to aerate or foam the liquid and comprises a steam generator to provide heated steam.

Compressed air is typically mixed with the heated steam and the resulting fluid is then injected via a supply tube and nozzle into the liquid creating froth. These steam based foaming devices are typically complicated and cumberstone machines due to utilisation of compressed air and steam.

A second type of foaming apparatus utilizes a plunger or rotating whisk-like component to whip the beverage into a froth without the need for hot steam.

Examples of these foaming devices are disclosed in the following documents.

US 5482367 discloses a device for manually whisking liquids. The device comprises a straight rod with twisted wire coils positioned at one end of the rod configured for agitating the liquid. The coiled wire head of the device is immersed in the liquid whereby the rod is rolled between the palms of a user's hands to rotate the device at speed to creating a liquid froth.

US 2001/0002891 discloses an automatic beverage frother in which a plurality of mesh paddles are rotatable about a central axle within a vessel to house the liquid. A motor housed below the vessel drives rotation of the axle and paddles. Foam is created as the paddles are displaced through the liquid and in particular as the liquid is forced through the mesh creating small bubbles which then accumulate at the liquid-vapour interface as a fine froth.

US 5580169 discloses a milk jug froth-foaming device. The jug has a container body having a lid that supports and guides a froth- foaming plunger.

The plunger comprises a disk-like element formed by a circumferential rim connected by spoke-like arms to a central portion to which a rod is attached whereby the disk-like element may be drawn up and down inside the container via the rod. A mesh extends between the spoke-like arms and serves to create air bubbles inside the liquid upon the reciprocating motion of the plunger within the container.

Mechanical aeration devices of the type disclosed in US 2001/000289 1 and US 5580169 are ideally suited for frothing milk and the like within a container that is sealed by a lid. The lid serves to prevent the liquid from splattering out of the container when agitated by the paddles or plunger.

So as to produce a variety of different types of coffee, coffee brewing machines usually comprise a milk frothing component which is suspended from the body of the coffee maker in the form of a pressurised steam supply nozzle or a whisk blade rotatably mounted on an axle. For ease of use, the nozzle or whisk blade is suspended from the coffee maker allowing a jug containing milk to be held in position over and about the nozzle or whisk blade submerged within the milk. Such an arrangement is not suitable for use with a lid to seal the jug and prevent milk splashing during foaming. Once submerged, the milk within the jug is aerated either by dispensing steam or rotating the whisk blade.

Whilst the use of steam based aeration apparatus is disadvantageous for the reasons for apparatus complexity and size, a number of problems exist with conventional whisk blade type aeration apparatus.

Splattering or splashing of the milk is a particular problem associated with these types of aeration apparatus that are designed to be submerged within the milk as the milk jug is held in a position at the whisk blade. Additionally, the time required to create the desired amount of foam is unsatisfactory with known rotating blade devices. Further disadvantages include the resulting low density or fineness of the foam created by known whisk blades and the difficulty associated with regular cleaning of such blades.

What is required therefore is beverage foaming apparatus that addresses these disadvantages.

Summary of the Invention

The apparatus of the present invention, either in isolation or forming part of a coffee machine, provides for the rapid creation of a fine beverage foam without the problem of beverage splattering during creation.

According to a first aspect of the present invention there is provided beverage foaming apparatus including aeration means for aerating a liquid, wherein the apparatus comprises: a paddle coupled to means for rotation of said paddle; a housing for said paddle configured to shroud said paddle, wherein said paddle is capable of rotation within said housing; and perforation means provided at said housing and positioned at said housing at a region adjacent to said paddle; at least one exhaust port provided at said housing in which said exhaust port is positioned at an upper region of said housing so as to be above the liquid level when said paddle and a portion of said housing are, in use, submerged in said liquid; wherein in use liquid within said housing is forced through said perforation means by rotation of said paddle within said housing.

By shrouding the rotatable paddle within the housing, agitation of the liquid in the immediate vicinity of the paddle is suppressed serving to prevent upwardly projected splashes from exiting the beverage container, such as a milk jug. By forcing the liquid through small apertures in the form of perforations or gauze, air bubbles of very small diameter are created within the liquid resulting in a very fine foam.

The creation of small bubbles on the outer surface of the housing further serves to suppress unwanted excessive agitation of the main body of liquid within the vessel outside of the paddle housing. As the foam is created on the outside of the housing, the force with which liquid is propelled towards the vessel walls, which would otherwise result in liquid splattering, is dampened by these tiny bubbles. Liquid agitation therefore is largely confined to the volume of liquid within the paddle housing and not the bulk liquid within the liquid vessel.

The present invention provides for the rapid creation of liquid foam as the paddle rotates quickly within the housing forcing liquid through the perforations.

This obviates unnecessary limitation of the rotation speed of the paddle imposed upon existing apparatus due to the disadvantageous upward splashing of the liquid.

Preferably, said exhaust port configured to allow passage of liquid and foam between the interior and exterior of the housing. The exhaust port functions to regulate the amount of liquid and foam within the housing. Preferably, the exhaust port is positioned remotely from the perforations. Preferably, the apparatus comprises two exhaust ports formed towards a first end of the housing whilst the perforation means are formed towards an opposite second end of the housing.

Preferably the housing is substantially cylindrical and in particular a cross-section of the interior surface of the housing is substantially circular.

Preferably, the housing is open at the first end and closed at the second end. Preferably, attachment means are provided at the open end enabling the housing to be releasably connected to a mount provided, at for example, a coffee maker. Preferably, the attachment means comprises at least one slot formed in the housing and the mount comprises at least one lug capable of being positioned within the slot to form a bayonet attachment by engagement of the lug within the slot. Alternatively, the mount, provided at the coffee maker may comprise the slot whilst the housing comprises at least one lug.

The paddle may be rotateably mounted on a spindle or shaft; alternatively the paddle may be detachably fixed to a rotatable shaft.

Preferably, the housing comprises grip means formed at an exterior surface of the housing enabling the housing to be gripped between thumb and fingers of a user. The grip means may be formed integrally or nonintegrally with the housing body in the form of ridges, grooves or any manner of surface profiling or roughness.

Preferably the perforations are formed as a mesh, gauze or other woven material capable of producing small bubbles as the liquid is forced through the material by rotation of the paddle within the housing. Preferably, the window comprises a nylon mesh. Alternatively stainless steel, may be used for the mesh.

Preferably, the lower region of the housing comprises at least one cut-out section or window across which the mesh-type material extends. Preferably, the housing comprises four or eight windows, radially distributed at the housing relative to the centrally positioned paddle shaft The present invention may further comprise a motor configured to drive rotation of the paddle.

According to a second aspect of the present invention there is provided a coffee maker comprising beverage foaming apparatus as described herein.

According to a third aspect of the present invention there is provided a method of foaming a beverage, said method comprising: coupling a rotatable paddle to a motor configured to drive rotation of said paddle; shrouding said paddle with a housing, said paddle capable of rotation within said housing wherein said housing comprises at least one exhaust port positioned at an upper region of said housing; submerging said paddle and a portion of said housing within a liquid wherein said exhaust port locates above the liquid level; rotating said paddle within said housing to force liquid within said housing through perforation means provided at said housing to create a foamed beverage and to aerate said liquid.

Brief Description of the Drawings

For a better understanding of the invention and to show how the same may be carried into effect, there will now be described by way of example only, specific embodiments, methods and processes according to the present invention with reference to the accompanying drawings in which: Figure 1 is a exploded perspective view of the paddle, paddle drive shaft and paddle housing according to a specific implementation of the present invention; Figure 2 is a perspective view of the paddle of figure 1; Figure 3 is a cross-sectional view of the paddle of figure 2; Figure 4 is a perspective, partial cut-away view of the housing of figure 1; Figure 5 is a cross-sectional view of the mount for the housing of figure 1; Figure 6 is a perspective view of a component of the attachment means configured to secure the housing of figure 4 to the mount of figure 5; Figure 7 illustrates a perspective cross-section view of the mount of figure 5; Figure 8 illustrates a cross-sectional side elevation view of the mount, paddle and housing of figure 1.

Detailed Description

There will now be described by way of example a specific mode contemplated by the inventors. In the following description numerous specific details are set forth in order to provide a thorough understanding. It will be apparent however, to one skilled in the art, that the present invention may be practiced without limitation to these specific details. In other instances, well known methods and structures have not been described in detail so as not to

unnecessanly obscure the description.

Referring to figure 1, a paddle 100 is mounted at one end at an elongate axle 102 via a mountaining washer 109. Axle 102 extends from a mount 103 provided at a base region 110 of a coffee maker (not shown). A drive motor (not shown) is coupled to shaft end 111 so as to drive rotation of paddle 100 relative tomount 103.

A paddle housing 101 is removeably attachable to mount 103 so as to shroud paddle 100 which is rotatable within the internal cavity defined by housing 101. Attachment means 108, in the form of a slot provided at a first end 112 of the housing engage with cooperating attachment means (not shown) provided at housing 103 as detailed with reference to figures 5 to 8. Towards a second end of the housing 113, a plurality of rectangular windows are provided through the walls of the housing exposing the housing interior. Gauze 105 is positioned at and extends over the area of each window.

Surface profiling 106 is provided on an external surface of the housing at a region approximately midway between the first and second ends 112, 113 respectively.

At an upper region of the housing towards first end 112 diametrically opposed holes 107 are provided through the housing wall.

Referring to figures 2 and 3, paddle 100 comprises substantially linear paddle blades 201 extending radially outwards from a central column 200 over the length of the column. When housed within the housing 100, a first lowermost end of paddle 202 engages in contact with a base portion of housing 109 referring to figure 4. Paddle 100 is connected to axle 102 via an upper end 203 of column 200 relative to lower end 202.

Referring to of figure 3, paddle 100 comprises a central bore 300 extending substantially the length of column 200. The diameter of the bore increases at a base section of the column 302 and an annular insert 301 secures the axle in position within the paddle.

A recessed portion 303 is provided at the bottom end of paddle 202.

According to the preferred embodiment,recess 303 is frusto-conical shaped.

Referring to figure 4, the shroud or housing 101 is open at the first end 112 so as to allow paddle 100 and a portion of axle 102 to be removeably inserted within the inner elongate cavity defined by the walls 400 of housing 101. So as to allow rotation of the paddle, housing 101 is substantially cylindrical along its length from first end 112 towards second end 113. The second end 113 of housing 101 is closed by a disklike section 117. To increase the structural strength of the lower region of housing 101, four strengthening struts 108 extend from a centre point of base 117 towards and in connect with the inner walls of housing 101 at its base.

A cone 109 projects upwardly from the central point of support struts 108 configured to engage with recess 303 formed within the end region of paddle 100.

According to a further embodiment of the present invention axle 102 extends through and beyond paddle 100. A hole formed in base section 117 allows a portion of axle 102 to extend therethrough. Accordingly, axle 102 is secured in a substantially centrally aligned position by locating within this hole.

Housing 101 comprises four windows cut into the lower region of housing walls 400 towards second end 113. Gauze 105 is positioned at the inner cavity defined by walls 400 so as to extend across each window 104. The surface area of each window 104 is completely covered by gauze 105. Gauze 105 may be formed as a single piece extending over all four windows or alternatively separate pieces may be positioned at each respective window.

A plurality of channels 106 are formed within the outer surface of walls 400 between an upper end of windows 104 and first end 112 of housing 101. The elongate channels extend over a portion of the outer surface only defining an area of a size sufficient to be gripped by the thumb and fingers of a user.

Positioned remotely from the windows 104 and between the upper end of channels 106 and first end 112 are the exhaust port holes 107. Between exhaust ports 107 and upper end 112 is attachment means 108. Attachments means 108 is defined by diametrically opposed cut-out regions extending from open end 112 towards exhaust ports 107. The width of each cut-out region decreases from a rim 406 defining end 112 towards a neck region 404 where each slot extends substantially parallel with rim 406 across a region of the housing wall 400 so as to define a notch 402. On its innermost edge, rim 406 is bordered by a chamfered lip 405 configured to mate with a corresponding chamfered portion (not shown) of the attachment means of mount 103.

Figures 5 to 7 illustrate selected components of the attachment means by which the paddle housing attaches to the mount positioned at the coffee machine base section 110. Housing mount 103 comprises a generally cylindrical configuration depressed within base section 110. A cavity 502 is formed at the interior of the cylindrical walls of mount 103 capable of housing an annular insert 500. Insert 500 comprises two diametrically opposed lugs 501 extending from an outer surface 601 at a lower end of the cylinder. Insert 500 is secured in position at mount 103 and is configured to receive first end 112 of housing 101.

Referring to figure 8, housing 101 is releaseably attached and suspended from the coffee machine base section 110 as the upper open end 112 is brought into contact with insert 500. Each lug 501 slides within the corresponding slot of the housing to region 401 whereby the housing is locked in position by rotation about its central axis to wedge each lug 501 under notch 402.

The width of paddle 100 in a direction perpendicular to the longitudinal axis of axle 102 is slightly smaller than the internal diameter of housing 101 at the region of windows 104 and mesh 105. Accordingly, paddle 100 is capable of free rotation within the cylindrical housing such that the paddle blades sweep past the mesh covered windows separated by a 1-5 mm. Rotation of the paddle within the housing is stabilised by cooperation between cone 109 which sits within recess 303 serving to prevent bending or twisting of axle 102 during rotation which would otherwise lead to contact of the paddle blades 201 with the internal side walls 400.

In use, a vessel, such as a milk jug, containing a liquid beverage, in particular milk, is brought into position towards base section 110 such that a portion of housing 101 and paddle 100 are submerged within the liquid. Exhaust ports 107 are positioned at an upper region of the housing so as to be above the liquid level when the paddle 100 and housing 101 are submerged.

Liquid floods the internal chamber of housing 101 through gauze 105. As the drive motor (not shown) is engaged, paddle 100 rotates about its central axis forcing liquid within housing 101 through gauze windows 105. By minimising the clearance distance between the outermost edges of paddle blades 201 and gauze 105 a finer foam is created in a shorter time.

Once the beverage has been aerated by the desired amount, the milk vessel is simply removed from close positioning with the housing and the beverage decanted as appropriate. The present foaming apparatus may be readily cleaned by simply releasing housing 101 at mount 103 to expose the paddle and axle 102. Both housing 101 and paddle 100 may then be wiped by a cloth.

Claims

Claims: 1. Beverage foaming apparatus including aeration means for

aerating a liquid, wherein the apparatus comprises: a paddle coupled to means for rotation of said paddle; a housing for said paddle configured to shroud said paddle, wherein said paddle is capable of rotation within said housing; and perforation means provided at said housing and positioned at said housing at a region adjacent to said paddle; at least one exhaust port provided at said housing in which, said exhaust port is positioned at an upper region of said housing so as to be above the liquid level when said paddle and a port portion of said housing are, in use, submerged in said liquid; wherein in use liquid within said housing is forced through said perforation means by rotation of said paddle within said housing.

2. The apparatus as claimed in claim I in which said exhaust port is configured to allow passage of liquid between an interior of said housing and an exterior of said housing.

3. The apparatus as claimed in claim I or claim 2 wherein said at least one exhaust port is positioned remote from said perforation means.

4. The apparatus as claimed in any preceding claim wherein at least one region of said housing is substantially cylindrical.

5. The apparatus as claimed in any preceding claim wherein said at least one exhaust port comprises two holes formed towards a first end of said housing and said perforation means are formed towards a second end of said housing.

6. The apparatus as claimed in claims 4 or claim 5 when dependent upon claim 4 wherein said cylindrical housing is open at a first end and closed at a second end.

7. The apparatus as claimed in any preceding claim wherein said housing further comprises attachment means configured to releasably attach said housing to a mount.

8. The apparatus as claims in claim 7 wherein said attachment means comprises at least one slot formed in said housing and said mount comprises at least one lug capable of being positioned within said slot such that by engagement of said at least one lug within said at least one slot said housing is removably attached to said mount.

9. The apparatus as claimed in claim 7 wherein said housing comprises at least one lug and said mount comprises at least one slot, said lug capable of being positioned within said slot to releasably attach said housing at said mount.

10. The apparatus as claimed in any preceding claim wherein said paddle is mounted at a rotatable shaft.

11. The apparatus as claimed in any preceding claim wherein said housing comprises grip means formed at an exterior surface of said housing, said grip means enabling said housing to be gripped between thumb and fingers of a user.

12. The apparatus as claimed in any preceding claim wherein said perforation means comprises perforations formed through the walls of said housing wherein liquid within said housing is capable of passing through said perforations.

13. The apparatus as claimed in any one of claims I to 11 wherein said perforation means comprises a mesh or gauze wherein liquid within said housing is capable of passing through the said mesh or gauze.

14. The apparatus as claimed in claim 13 wherein said housing comprises four windows, said mesh or gauze being positioned at said windows.

17. The apparatus as claimed in any preceding claim further comprising a motor configured to drive rotation of the said paddle.

18. A coffee maker comprising beverage foaming apparatus according to any preceding claim.

19. A method of foaming a beverage, said method comprising: coupling a rotatable paddle to a motor configured to drive rotation of said paddle; shrouding said paddle with a housing, said paddle capable of rotation within said housing wherein said housing comprises at least one exhaust port positioned at an upper region of said housing; submerging said paddle and a portion of said housing within a liquid wherein said exhaust port locates above the liquid level; rotating said paddle within said housing to force liquid within said housing through perforation means provided at said housing to create a foamed beverage and to aerate said liquid.

20. The method as claimed in claim 19 further comprising: releasably attaching said housing over and about said paddle to shroud said paddle prior to said step of rotating said paddle within said housing.

21. The method as claimed in claim 20 wherein said housing is releasebly held in position over and about said paddle via bayonet attachment means provided at said housing and a mount for said housing.

22. The method as claimed in any one of claims 19 to 21 wherein said perforation means comprises perforations formed through the walls of said housing.

23. The method as claimed in any one of claims 19 to 22 wherein said perforation means comprises a mesh or gauze enclosing at least one open window portion of said housing.