GB2548864A

GB2548864A - Blades for food processors

Info

Publication number: GB2548864A
Application number: GB1605412.4A
Authority: GB
Inventors: Palmer Paul
Original assignee: Kenwood Ltd
Current assignee: Kenwood Ltd
Priority date: 2016-03-31
Filing date: 2016-03-31
Publication date: 2017-10-04
Also published as: WO2017168178A1

Abstract

A method of designing a tool for a food processor, especially a spatially unbalanced tool, comprising receiving an intended (e.g. a decorative) shape and an intended axis of rotation. The method further comprises dividing the tool into portions and calculating a preferred density for each portion such that the centre of mass of the tool lies on or adjacent the intended axis of rotation and the tool is dynamically balanced. The density variations may be implemented by creating cavities within the tool or by adding denser material. Preferably the tool is 3D printed. The tool may include a blade 106 with a decorative shape, e.g. a monkey. Also including a tool formed by this method and a computer program/computing device for performing the method.

Description

BLADES FOR FOOD PROCESSORS

The present invention relates to a food processor device and, more particularly, to a blade for a food processor device. This invention also relates to a method of producing a blade for a food processor device.

Typically a food processor is a multipurpose kitchen appliance which helps and reduces physical work required while food preparation and cooking. The food processor is a motor-driven kitchen machine in which a rotary tool is typically mounted in the base of a bowl and driven from beneath the bowl by means of a suitable drive coupling from an electric motor. Food processors may also include juicers, blenders, mixers and grinders. Historically, food processors are sold with multiple blades of various shapes, each blade designed for a specific purpose. Examples of such blades include: disc blades, stem blades, dough blades, multipurpose blades, fine slice discs and egg whips. However, the design of the blades is very limited. In order to achieve smooth rotation of blades, a balance around the axis of rotation is typically maintained by placing a number of blades symmetrically around the axis, or by including appropriate counterweights for the blades.

It is an aim of the present invention to provide a blade for a food processor which at least alleviates some of these problems.

According to one aspect, there is provided a method of designing a tool for a food processor comprising: receiving an intended tool shape; receiving an intended axis of rotation; determining a distribution of a plurality of portions, the plurality of portions together forming the intended tool shape, with each portion having a different density, such that the centre of mass of the tool lies on or adjacent the intended axis of rotation; and providing an output defining the determined distribution of portions.

By determining a distribution of portions with each portion having a different density an arbitrary tool shape can be enabled, and the tool shape need not be limited to a shape that is balanced for rotation by virtue of its geometry. This can enable user selection of a decorative tool shape and thereby enhance the appeal of the tool to a user without suffering a performance penalty of the tool due to rotational imbalance.

As used herein ‘adjacent’ preferably means within 1cm, and more preferably within 1mm, and more preferably within 0.5mm, and more preferably within 0.1mm.

For versatility the method may further comprise receiving a selection of one or more material(s) and/or material density(ies).

For convenience the method may further comprise forming a tool according to the determined distribution of portions.

For speed and ease of production the forming may be by 3D printing.

For efficiency the method may further comprise determining, based on the intended tool shape, an intended tool orientation, an intended point of attachment of the tool, and/or the intended axis of rotation. The determining may take place following receipt of an intended tool shape, in order to provide an intended axis of rotation, and/or prior to determining the distribution of the plurality portions. This can enable user selection of a desired shape; subsequent determination by the design process of the intended axis of rotation (without user selection of the intended axis of rotation, optionally with user confirmation of an intended axis of rotation determined by the design process); then the design process can receive the thus determined intended axis of rotation and proceed to determine the distribution of the plurality portions as aforementioned.

For efficiency the method may further comprise determining a number of portions to be distributed.

For efficiency the method may further comprise optimising the distribution of the plurality of portions for proximity of the centre of mass to an intended point of attachment of the tool.

For efficiency the method may further comprise optimising the distribution of the plurality of portions for optimising the moment of inertia of the tool about the intended axis of rotation. Optimising may comprise reducing or increasing the moment of inertia of the tool about the intended axis of rotation. Reducing the moment of inertia can enable fast rotation of the tool. Increasing the moment of inertia can be favourable for transferring energy to food being processed.

For efficiency the method may further comprise optimising the distribution of the plurality of portions for optimising the weight of the tool. Optimising may comprise reducing or increasing the weight. The weight may be reduced for a lightweight tool, or increased for a tool that can rotate with greater momentum.

For efficiency the method may further comprise applying a scaling factor to the intended tool shape. This can enable the tool to be formed with a desired dimension, for example no larger than a maximum width or a maximum height.

For tool strength the distribution of the plurality of portions may such that at the surface of the intended tool shape at least a predetermined minimal wall thickness is provided.

For efficiency the method may further comprise determining whether, if the tool were formed of a homogeneous solid material in the intended shape, it would be imbalanced around the intended axis of rotation. Preferably the distribution of the plurality of portions is applied only if, were the tool formed of a homogeneous solid material in the intended shape, it would be imbalanced around the intended axis of rotation. For efficiency a geometrical rotation imbalance value of the intended tool shape may be non-negligible.

Imbalance may be if a centre of mass does not lie on or adjacent the intended axis of rotation, and /or if a centre of mass lies away from the intended axis of rotation. Imbalance may be when the centre of mass is more than 1cm from the intended axis of rotation, or more than 1mm from the intended axis of rotation, or more than 0.5mm from the intended axis of rotation.

For efficiency the plurality of portions may comprise a structural portion defining an envelope of the intended tool shape and a balancing portion embedded in the structural portion.

For compactness the balancing portion may have a higher density than the structural portion.

For lightness the balancing portion may have a lower density than the structural portion.

For simplicity the structural portion may comprise a structure defining a cavity, and the balancing portion may comprise a gas in the cavity.

For ease of cleaning and for appearance the cavity may be concealed within the structural portion.

For good cutting performance the plurality of portions may comprise a blade portion for cutting food embedded in the tool.

For good cutting performance the blade portion may comprise a metal.

For ease of manufacture and versatility the structural portion may be a polymer.

For user appeal the intended tool shape may be a decorative shape.

According to another aspect, there is provided a tool produced according to a method as aforesaid.

According to another aspect, there is provided a tool for a food processing machine, the tool comprising an intended tool shape and an intended axis of rotation, the tool being formed of a plurality of portions, the plurality of portions together forming the intended tool shape, with each portion having a different density, such that the centre of mass of the tool lies on or adjacent the intended axis of rotation, wherein if the tool were formed of a homogeneous solid material in the intended shape then it would be imbalanced around the intended axis of rotation.

For efficiency a geometrical rotation imbalance value of the intended tool shape may be non-negligible.

For good cutting performance the blade portion may comprise a metal.

For user appeal the intended tool shape may be a decorative shape.

According to another aspect, there is provided a computing device for designing a tool for a food processor adapted to perform steps comprising: receiving an intended tool shape; receiving an intended axis of rotation; determining a distribution of a plurality of portions, the plurality of portions together forming the intended tool shape, with each portion having a different density, such that the centre of mass of the tool lies on or adjacent the intended axis of rotation; and providing an output defining the determined distribution of portions.

For versatility the computing device may further be adapted to perform a step of receiving a selection of one or more material(s) and/or material density(ies).

For convenience the computing device may further be adapted to perform a step of controlling formation of a tool according to the determined distribution of portions.

The computing device may further be adapted to perform a step according a method as aforesaid.

According to another aspect, there is provided a computer program product adapted to perform, when executed, the steps of: receiving an intended tool shape; receiving an intended axis of rotation; determining a distribution of a plurality of portions, the plurality of portions together forming the intended tool shape, with each portion having a different density, such that the centre of mass of the tool lies on or adjacent the intended axis of rotation; and providing an output defining the determined distribution of portions.

For versatility the computer program product may further be adapted to perform a step of receiving a selection of one or more material(s) and/or material density(ies).

For convenience the computer program product may further be adapted to perform a step of controlling formation of a tool according to the determined distribution of portions.

The computer program product may further be adapted to perform a step according a method as aforesaid.

According to another aspect, there is provided a food processor (100) comprises a container (102) with a lid (104) for providing an enclosure for a food item. The food processor (100) further includes a base unit (108) with controls (110) to dock the container (102). Yet further, the food processor (100) includes a blade detachably connected to the base of the container (102), wherein the blade is specially designed such that the blade is spatially unbalanced but dynamically balanced by means of distribution of mass.

According to another aspect, there is provided a cloud comprises a 3D model database storing pictures and recipes of a plurality of food items. The cloud further includes a design service unit configured to obtain an outer shape design of a blade, analyze the outer shape design, create a 3D model by optimizing 3D meshes within the blade based on the outer shape design and send the 3D model to a 3D printer for printing.

According to another aspect, there is provided a method for producing a blade for a food processor (100) comprises obtaining an outer shape design of a blade, analyzing the outer shape design, creating a 3D model by optimizing 3D meshes within the blade based on the outer shape design; and sending the 3D model to a 3D printer for printing.

The invention extends to a method substantially as herein described and/or as illustrated with reference to the figures. The invention also extends to a tool substantially as herein described and/or as illustrated with reference to the figures. The invention also extends to a computing device substantially as herein described and/or as illustrated with reference to the figures. The invention also extends to a computer program product substantially as herein described and/or as illustrated with reference to the figures.

Other technical advantages will be readily apparent to one skilled in the art from the following figures, descriptions and claims. Moreover, while specific advantages have been enumerated above, various embodiments may include all, some or none of the enumerated advantages.

Any apparatus feature as described herein may also be provided as a method feature, and vice versa. As used herein, means plus function features may be expressed alternatively in terms of their corresponding structure.

Any feature in one aspect of the invention may be applied to other aspects of the invention, in any appropriate combination. In particular, method aspects may be applied to apparatus aspects, and vice versa. Furthermore, any, some and/or all features in one aspect can be applied to any, some and/or all features in any other aspect, in any appropriate combination.

It should also be appreciated that particular combinations of the various features described and defined in any aspects of the invention can be implemented and/or supplied and/or used independently.

These and other aspects of the present invention will become apparent from the following exemplary embodiments of the invention that are described with reference to the accompanying drawings in which:

Figure 1A shows a side view of a food processor device when the device is not in operation,

Figure 1B shows a side view of the food processor device when the device is in operation, and

Figures 2A and 2B show details of a blade of the food processor,

Figure 3 shows a 3D printer with a 3D print of a blade,

Figure 4 shows an ecommerce website, and

Figure 5 shows a flowchart of a method to 3D print customized blades for food processors.

Referring now to Figs. 1A and 1B, in which corresponding features carry the same reference numbers, a food processor 100 comprises a container 102 with a lid 104 for providing an enclosure for a food item. The container 102 also includes a blade 106. The blade 106 may be detachably connected to the container. The food processor 100 further includes a base unit 108 on which the container 102 rests. The base unit 108 includes controls 110 that allow a user to operate the food processor 100. As shown, the blade 106 is shaped like a monkey. The blade 106 may be shaped in any other suitable shape as well. Some other exemplary shapes are shown in Figure 4. The blade 106 is designed such that when the user uses controls 110 to rotate the blade 106 (e.g. by starting operation of the food processor 100), the blade 106 rotates in an intended orientation (e.g. with the monkey in an upright vertical position) as shown in Fig. 1B.

In order to produce the blade, in brief, a desired shape for a blade with a given axis of rotation is uploaded to a computing device. The shape is analysed to determine its centre of mass (assuming a solid, homogeneous constituency). Where the shape is such that a solid, homogeneous blade of that shape would be unbalanced about the axis of rotation, an electronic blade-design is automatically created where the density of the blade varies so as to balance it. This is done either by creating one or more cavities within the blade, or by adding denser material. The blade design is then sent to be 3D printed. The blade is thus suitably balanced and can be made quickly and to any design. The blade can for example be used for cutting, mashing, stirring, mixing, chopping and/or blending. The blade may be detachable and may be used with a blender, food processor, chopper or other domestic appliance.

Figure 2 shows details of the blade 106 of the food processor 100. The monkey shaped blade 106 may fail to maintain a balanced spin if its centre of mass 202 is out of alignment with the axis of rotation (intended axis 204). The centre of mass lies on the axis of rotation when the following condition is true:

evaluated over the volume V of the blade, where r is the distance from the axis of rotation and dm is the mass at the point r, and p is the density at the point r.

The shape of the design is analyzed in respect of a desired axis of rotation. The density distribution within the desired design is optimized for rotational stability (such that the centre of mass falls on the intended axis of rotation) based on which a 3D model is created. The 3D model may be stored as a Computer Aided Design (CAD) file. The 3D model is created by tweaking 3D meshes within the blade 106 to create hollow, interior spaces that keep the object balanced. For example, the tail 206 of the monkey may be hollow as shown in Fig. 2B. A number of computational approaches can analyze a given desired tool shape with a desired axis of rotation in order to determine a suitable distribution of densities (e.g. hollow cavities and solid material) within the shape. For example, a finite element analysis of may be used to determine a suitable location for a cavity within the otherwise solid tool, and the suitable cavity extent.

The computation may operate within certain constraints, for example it may be defined that the surface of the tool be continuous and at least of a certain thickness, such that cavities can only be located at the interior of the tool. The computation may scale a user-selected shape to a predetermined size such as is suitable for a particular food processor or in order for the tool to be of a particular weight or in order to accommodate pre-formed parts to be embedded in the tool.

For example an attachment portion may be embedded in the tool for attachment to a particular food processor. The user may input a 2-dimensional outline and the thickness of the tool be determined by the analysis, for example with a pre-set uniform tool thickness or with varying thickness.

The constraints considered by the computation may additionally include characteristics of the working-medium on which the tool will act (e.g., foods and beverages) including the density, abrasiveness and viscosity of this working medium. The working medium on which the tool will act, and the speed at which it will do so, can be identified by the user when uploading the shape, or be innate to the tool’s intended use (for example, a tool identified as a dough-hook will act on dough at a relatively slow speed) as identified by the user. The characteristics of the working medium may be stored by the computing device on an internal database/ memory, or recovered from a database external to the computing device via, e.g., the internet. Once these characteristics have been retrieved by the computing device, the computing device may then calculate the strain and impact-force experienced by component parts of the tool as it works on the working medium at a known speed, and configure the tool components to be sufficiently strong/dense to resist this strain and impact-force without deformation, breaking, or abrasion.

Alternatively the tool may be configured for use with any working medium within the field of intended use (e.g., food blending) at a speed or range of speeds specific to the field of intended use identified by the user or the computing device. Maximum/minimum strain tolerance may be stored on the computing device or retrieved from an external database such as, for example, a database of a safety standards organisation.

The density distribution within the desired design (e.g. location and size of the cavity or cavities) may further be optimised, for example aiming to bring the centre of mass near to the point of attachment of the tool to the drive, and/or aiming to minimise the moment of inertia in order to enable more efficient drive of the tool. The blade design may be optimised such that at least a specific minimum strength of the resulting blade is provided throughout the blade. The blade design may be optimised such that the resulting blade is lighter than a specific maximum weight value.

The analysis of the desired tool shape may be adapted to determine a desired axis of rotation in the absence of an indication from the user, for example based on image recognition and a most likely orientation. The analysis of the desired tool shape may also be adapted to determine an attachment region of a desired tool shape in the in the absence of an indication of a desired axis of rotation from the user. For example, once a most likely orientation is determined, an extremity in the desired orientation can be identified as the attachment region. The axis of rotation can then be determined as the axis thought the attachment region and in the most likely orientation.

Further materials (having different density) may form portions of the blade 106. For example a metal is incorporated in the example shown in Figures 1A to 2B, where a metallic blade portion 208, 210, 212 is incorporated to form a blade for cutting. In the illustrated example, the hands 208, 210 and the foot 212 incorporate sharp metallic parts. The location of the blade portions can be set by a user, or it can be determined by analysis of a desired tool shape, for example at extremities. The analysis of the desired tool shape for balancing takes into account the location and density of the blade portions and adapts the density distribution accordingly. In a variant a further material is merely embedded for balancing purposes, and performs no additional function (e.g. cutting). In a variant no empty or air-filled cavities are created, but instead a portion of material with a higher or lower density than the surrounding material is embedded.

The blade 106 (shown in Fig. 2B) is of a shape that is unbalanced with respect to an upright orientation of the character if the blade is of a uniform material. But because a non-uniform density distribution within the blade is used the blade is balanced in the desired upright orientation. By means of distribution of mass or density the centre of mass 202 lies on the axis of rotation (intended axis 204). The term / rdV evaluated over the volume V of the blade, where r is the distance from the axis of rotation, gives an indication of imbalance of rotation if the blade with the desired shape is formed of a uniform material (and has a uniform density across the shape), and so an indication of the rotational instability of a particular desired blade shape with respect to a particular desired axis of rotation. The term / rdV is used as a geometrical rotation imbalance value. In conventional tool shapes with a uniform density distribution within the tool the balance is achieved by the geometry of the tool shape, and the geometrical rotation imbalance value is zero. Conversely tool shapes with a geometrical imbalance value that is not zero have a shape that is not balanced about the intended axis of rotation.

Once the 3D model with the desired mass distribution is created, it is sent to a 3D printer 300 for printing a physical copy of the blade 106 as shown in Figure 3. 3D printing uses additive processes, in which successive layers of material are laid down under computer control. Therefore, objects of almost any shape or geometry can be produced from a 3D model. The 3D printer 300 may employ any suitable technology such as Direct Laser Metal Sintering (DLMS), Selective Laser Sintering (SLS), Fused Deposition Modelling (FDM) and Stereo Lithography (SLA). The material used by the 3D printer 300 may depend on a particular task, for example, a blade designed for mixing may be all plastic while a blade designed for cutting may have metallic parts. The information about type of material to be used for each part of the blade 106 may be included in the 3D model itself, such that a 3D printer can access the information and use appropriate materials for various parts of the blade 106. Alternatively the 3D printer 300 may print a mould that will be used in an additional moulding step (e.g., injection moulding) to create the desired blade 106, or another traditional manufacturing method (e.g., stamping, milling, carving, etc.) may be carried out using e.g., a CNC machine to produce the blade 106 based on the 3D model.

Further, a user may create their own 3D models from which they can print blades for their food processors. Alternatively, they may purchase 3D models available on an ecommerce website 400 as shown in Figure 4. The ecommerce website 400 may be stored on a cloud. The website 400 shows 3D models 402-408. Further, 3D printed blades based on the 3D models 402-408 may be directly available for sale on the ecommerce website 400. Yet further, users may submit the outer shape designs on the ecommerce website 400 using the option 410. They may submit an outer shape design via one or more of a photograph, a hand drawing, and a digital drawing. The ecommerce website 400 uses a method 500 (explained in detail in conjunction with Fig. 5 below) to produce a 3D model corresponding to the submitted outer shape design. Then, the submitted designs may be 3D printed and shipped to the respective users, or downloaded by the user for printing using their own 3D printer. The user may also select the model of their food processor on the ecommerce website 400 such that a blade of appropriate size is printed by a 3D printer.

Fig. 5 shows a flowchart illustrating a method 500 for generating a customized blade 106 for the food processor 100 according to the present disclosure. At step 502, a design of the blade 106 is obtained. The design describes the external appearance of the blade. For example, the design of the blade 106 describes the external appearance of the monkey. Next, the design is analyzed at step 504. Then at step 506 the design is optimized wherein 3D meshes are defined to create a 3D model which includes hollow spaces. The 3D model is created such that it is suitable for a particular task and improves performance. Finally, at step 508, the 3D model is fed to a 3D printer to obtain a 3D printed object.

Further modifications will be apparent to those skilled in the art without departing from the scope of the present invention. A selection of features of the disclosure is now summarized. A food processor (100) comprising: a container (102) with a lid (104) for providing an enclosure for a food item; a base unit (108) to dock the container (102); a blade detachably connected to the base of the container (102), wherein the blade is specially designed such that the blade is spatially unbalanced but dynamically balanced by means of distribution of mass.

Optionally: • including one or more of a juicer, a blender, a mixer and a grinder. • wherein an outer shape design of the blade is obtained; • wherein the outer shape design is analyzed; • wherein a 3D model is created by optimizing 3D meshes within the blade. • wherein information about type of material to be used for each part of the blade (106) is included in the 3D model. • wherein the 3D meshes include hollow interior spaces that keep the blade dynamically balanced. • wherein the 3D model is provided to a 3D printer (300) to print a physical copy of the blade. • wherein the 3D printer (300) employs at least one of Direct Laser Metal Sintering (DLMS), Selective Laser Sintering (SLS), Fused Deposition Modelling (FDM) and Stereo Lithography (SLA). • wherein the outer shape design of the blade is provided by a user. • wherein the outer shape design of the blade is provided by a manufacturer. A cloud comprising: a 3D model database storing 3D models of various blades; and a design service unit configured to: obtain an outer shape design of a selected blade; analyze the outer shape design; create a 3D model by optimizing 3D meshes within the blade based on the outer shape design; and send the 3D model to a 3D printer for printing.

Optionally: • wherein a user may provide the outer shape design. • wherein the user may provide one or more of a photograph, a hand drawing, a digital drawing for the outer shape design. • wherein the design service unit creates the 3D model wherein the 3D meshes within the blade include hollow interior spaces that keep the blade dynamically balanced. A method for producing a blade for a food processor, the method comprising: obtaining an outer shape design of a blade; analyzing the outer shape design; creating a 3D model by optimizing 3D meshes within the blade based on the outer shape design; and sending the 3D model to a 3D printer for printing.

Optionally: • wherein the food processor (100) includes one or more of a juicer, a blender, a mixer and a grinder. • wherein a user may provide the outer shape design. • wherein the outer shape design of the blade is provided by a manufacturer. • wherein the 3D meshes include hollow interior spaces that keep the blade dynamically balanced.

It will be understood that the present invention has been described above purely by way of example, and modifications of detail can be made within the scope of the invention.

The invention described here may be used in any kitchen appliance and/or as a stand-alone device. This includes any domestic food-processing and/or preparation machine, including both top-driven machines and bottom-driven machines. It may be implemented in heated and/or cooled machines. The invention may also be implemented in both hand-held (e.g., hand blenders) and table-top (e.g., blenders) machines. It may be used in a machine that is built-in to a work-top or work surface, or in a stand-alone device. The invention can also be implemented as a stand-alone device, whether motor-driven or manually powered.

Whilst the invention has been described in the field of domestic food processing and preparation machines, it can also be implemented in any field of use where efficient, effective and convenient preparation and/or processing of material is desired, either on an industrial scale and/or in small amounts. The field of use includes the preparation and/or processing of: chemicals; pharmaceuticals; paints; building materials; clothing materials; agricultural and/or veterinary feeds and/or treatments, including fertilisers, grain and other agricultural and/or veterinary products; oils; fuels; dyes; cosmetics; plastics; tars; finishes; waxes; varnishes; beverages; medical and/or biological research materials; solders; alloys; effluent; and/or other substances.

Each feature disclosed in the description, and (where appropriate) the claims and drawings may be provided independently or in any appropriate combination.

Reference numerals appearing in the claims are by way of illustration only and shall have no limiting effect on the scope of the claims.

Claims

1. A method of designing a tool for a food processor, comprising: receiving an intended tool shape; receiving an intended axis of rotation; determining a distribution of a plurality portions, the plurality of portions together forming the intended tool shape, with each portion having a different density, such that the centre of mass of the tool lies on or adjacent the intended axis of rotation; and providing an output defining the determined distribution of portions.

2. A method according to Claim 1 further comprising receiving a selection of one or more material(s) and/or material density(ies).

3. A method according to Claim 1 or 2 further comprising forming a tool according to the determined distribution of portions.

4. A method according to Claim 3 wherein the forming is by 3D printing.

5. A method according to any preceding claim further comprising determining, based on the intended tool shape, an intended tool orientation, an intended point of attachment of the tool, and/or the intended axis of rotation.

6. A method according to any preceding claim further comprising determining a number of portions to be distributed.

7. A method according to any preceding claim further comprising optimising the distribution of the plurality of portions for proximity of the centre of mass to an intended point of attachment of the tool.

8. A method according to any preceding claim further comprising optimising the distribution of the plurality of portions for optimising the moment of inertia of the tool about the intended axis of rotation.

9. A method according to any preceding claim further comprising optimising the distribution of the plurality of portions for optimising the weight of the tool.

10. A method according to any preceding claim further comprising applying a scaling factor to the intended tool shape.

11. A method according to any preceding claim wherein the distribution of the plurality of portions is such that at the surface of the intended tool shape at least a predetermined minimal wall thickness is provided.

12. A method according to any preceding claim further comprising determining whether, if the tool were formed of a homogeneous solid material in the intended shape, it would be imbalanced around the intended axis of rotation.

13. A method according to any preceding claim wherein the plurality of portions comprises a structural portion defining an envelope of the intended tool shape and a balancing portion embedded in the structural portion.

14. A method according to Claim 13 wherein the balancing portion has a higher density than the structural portion,

15. A method according to Claim 13 wherein the balancing portion has a lower density than the structural portion,

16. A method according to Claim 15 wherein the structural portion comprises a structure defining a cavity, and the balancing portion comprises a gas in the cavity.

17. A method according to Claim 16 wherein the cavity is concealed within the structural portion.

18. A method according to any of Claims 13 to 17 wherein the structural portion is a polymer.

19. A method according to any preceding claim wherein the plurality of portions comprises a blade portion for cutting food embedded in the tool.

20. A method according to Claim 19 wherein the blade portion comprises a metal.

21. A method according to any preceding claim wherein the intended tool shape is a decorative shape.

22. A tool formed according to a design produced by the method of any of Claims 1 to 21.

23. A tool for a food processing machine, the tool comprising an intended tool shape and an intended axis of rotation, the tool being formed of a plurality of portions, the plurality of portions together forming the intended tool shape, with each portion having a different density, such that the centre of mass of the tool lies on or adjacent the intended axis of rotation, wherein if the tool were formed of a homogeneous solid material in the intended shape then it would be imbalanced around the intended axis of rotation.

24. A tool according to Claim 23 wherein the plurality of portions comprises a structural portion defining an envelope of the intended tool shape and a balancing portion embedded in the structural portion.

25. A tool according to Claim 24 wherein the balancing portion has a higher density than the structural portion,

26. A tool according to Claim 24 wherein the balancing portion has a lower density than the structural portion,

27. A tool according to Claim 26 wherein the structural portion comprises a structure defining a cavity, and the balancing portion comprises a gas in the cavity.

28. A tool according to Claim 27 wherein the cavity is concealed within the structural portion.

29. A tool according to any of Claims 24 to 28 wherein the structural portion is a polymer.

30. A tool according to any of Claims 23 to 29 wherein the plurality of portions comprises a blade portion for cutting food embedded in the tool.

31. A tool according to Claim 30 wherein the blade portion comprises a metal.

32. A tool according to any of Claims 23 to 31 wherein the intended tool shape is a decorative shape.

33. A computing device for forming a tool for a food processor adapted to perform steps comprising: receiving an intended tool shape; receiving an intended axis of rotation; determining a distribution of a plurality of portions, the plurality of portions together forming the intended tool shape, with each portion having a different density, such that the centre of mass of the tool lies on or adjacent the intended axis of rotation; and providing an output defining the determined distribution of portions.

34. A computing device according to Claim 33 further adapted to perform a step of receiving a selection of one or more material(s) and/or material density(ies).

35. A computing device according to Claim 33 or 34 further adapted to perform a step of controlling formation of a tool according to the determined distribution of portions.

36. A computing device according to any of Claims 33 to 35 further adapted to perform a step according to the method of any of Claims 1 to 21.

37. A computer program product adapted to perform, when executed, the steps of: receiving an intended tool shape; receiving an intended axis of rotation; determining a distribution of a plurality of portions, the plurality of portions together forming the intended tool shape, with each portion having a different density, such that the centre of mass of the tool lies on or adjacent the intended axis of rotation; and providing an output defining the determined distribution of portions.

38. A computer program product according to Claim 37 further adapted to perform a step of receiving a selection of one or more material(s) and/or material density(ies).

39. A computer program product according to Claim 37 or 38 further adapted to perform a step of controlling formation of a tool according to the determined distribution of portions.

40. A computer program product according to any of Claims 37 to 39 further adapted to perform a step according to the method of any of Claims 1 to 21.

41. A method substantially as herein described and/or as illustrated with reference to the figures.

42. A tool substantially as herein described and/or as illustrated with reference to the figures.

43. A computing device substantially as herein described and/or as illustrated with reference to the figures.

44. A computer program product as herein described and/or as illustrated with reference to the figures.