GB2619984A - Planetary ball mill apparatus, system and method - Google Patents

Abstract

A ball mill apparatus 10 comprises a planetary gear arrangement 12 comprising a drive gear 14 which defines a sun gear of the planetary gear arrangement 12 and one or more driven gears 16 which defines planets of the planetary gear arrangement 12. The driven gears 16 are configured for location around and to mesh with the drive gear 14, rotation of the drive gear 14 driving rotation of the one or more driven gears 16 around the drive gear. The apparatus 10 comprises a rotary drive arrangement configured to drive rotation of the drive gear 14. At least one of said driven gears 16 forms or is configured to receive a receptacle for receiving a material to be ground and a grinding media. The drive 14 and driven 16 gears may be directly or indirectly engaged, in form of spur or helical gears. There may be a ring gear 58, that defines a housing of the transmission arrangement. The apparatus may comprise a heating or cooling arrangement, to regulate temperature of the ball mill apparatus.

Description

PLANETARY BALL MILL APPARATUS, SYSTEM AND METHOD

FIELD

This relates to a planetary ball mill apparatus, a milling system comprising the planetary ball mill apparatus and a milling method using the planetary ball mill apparatus or milling system.

BACKGROUND

Ball milling is a grinding technique whereby a solid or liquid material is repeatedly ground over time in order to yield solids, powders and/or emulsions with desired properties.

One form of bill mill apparatus, known as a planetary bill mill, employs a planetary transmission mechanism to rotate a receptacle, commonly referred to as a grinding jar, into which grinding media and material to be ground are located. Rotation of the grinding jar by the transmission mechanism causes the grinding media to interact with the material to be ground and thereby obtain a material with the required properties.

Planetary ball mill apparatus' are used widely in both academic and industrial laboratories in order to grind materials in a range of scientific areas including geology, metallurgy, biology, chemistry, pharmaceuticals, ceramics, metal alloys, and materials science and, amongst other things, has been employed to mix colloids, fluids, powders, pastes, creams, grease, resins, inks, paints and silicone mixtures.

Despite their widespread use, there are a number of drawbacks with conventional equipment and techniques.

For example, conventional planetary ball mill apparatus' are heavy and bulky pieces of equipment and take up a significant footprint within the laboratory environment. Moreover, conventional planetary ball mill apparatus' offer limited throughput of material to be ground. Conventional planetary ball mill apparatus' also suffer from the problem that they overheat, with the result that the grinding operation often has to be paused at regular intervals, in some cases every 30 minutes, to allow the material to be ground and/or grinding jars to cool down. Indeed, it has been found that if left to run continuously, the material to be ground has reached temperatures up to 600 C.

SUMMARY

Aspects of the present disclosure relate to a planetary ball mill apparatus, a milling system comprising the planetary ball mill apparatus and to a milling method using the planetary ball mill apparatus or milling system.

According to a first aspect, there is provided a planetary ball mill apparatus, comprising: a transmission arrangement comprising: a drive gear, wherein the drive gear defines a sun gear of the transmission arrangement; and one or more driven gears, wherein the one or more driven gears form planet gears of the transmission arrangement, wherein the transmission arrangement is configured such that rotation of the drive gear drives rotation of the one or more driven gears; and a rotary drive arrangement configured to drive rotation of the transmission arrangement, wherein at least one of said driven gears forms or is configured to receive therein a receptacle for receiving a material to be ground and a grinding media.

In use, the material to be ground, e.g. a material sample, and the grinding media are placed within the one or more receptacles formed by or received within the one or more driven gears. The rotary drive arrangement drives rotation of the transmission arrangement, rotation of the one or more receptacles by the transmission arrangement causing the grinding media to interact with the material to be ground, thereby obtaining a material with the required properties.

The ball mill apparatus provides a number of significant benefits over conventional equipment.

For example, the provision of a ball mill apparatus comprising one or more receptacles which are formed by or received within the driven gears means that the receptacles -and their contents in use -are aligned with, substantially aligned with or at least partially aligned with On other words in the same plane as) the drive gear. This results in a reduction in the asymmetric centrifugal forces experienced by the receptacles and their contents, such that the receptacles can operate effectively at higher rotational velocity. This in turn means that the efficiency with which the apparatus grinds the material to be ground can be improved. The alignment between the drive gear and the driven gears also provides a design which is also inherently safe, as any catastrophic failure will be contained within a housing of the apparatus.

The alignment between the drive gear and the driven gears also results in a compact design, such that the apparatus has a small footprint in comparison to conventional ball mill apparatus'. Moreover, the provision of a ball mill apparatus wherein the receptacles are formed by or received within the driven gears significantly simplifies the design of the ball mill apparatus.

As described above, the apparatus comprises at least one driven gear which forms a receptacle or which is configured to receive therein a receptacle for receiving the material to be ground and the grinding media.

In embodiments where the driven gear forms the receptacle, the receptacle and the driven gear may be integrally formed or form a unitary construction. The driven gear may comprise a first, geared, portion which operatively forms part of the transmission arrangement and a second, container, portion suitable for holding the material to be ground and the grinding media and which defines the receptacle.

In embodiments where the driven gear is configured to receive the receptacle, the driven gear and the receptacle form separate components. The driven gear may comprise a first, geared, portion which operatively forms part of the transmission arrangement and a second, recess or bore, portion suitable for receiving at least part of the receptacle. When assembled, the receptacle may be at least partially disposed within a body of the driven gear.

In embodiments where the driven gear is configured to receive the receptacle, the receptacle may comprise or take the form of a container for holding the material to be ground and the grinding media and which defines the receptacle. In some embodiments, the receptacle may be constructed from a harder material than the driven member. Beneficially, this may facilitate the milling of harder materials.

The transmission arrangement may comprise or take the form of a planetary or epi-cyclic gear arrangement.

The driven gears may be configured for location around the drive gear.

The drive gear and the one or more driven gears may be directly engaged. For example, the drive gear and the one or more driven gears may be positioned so that the one or more driven gears mesh with the drive gear.

In use, engagement of the one or more driven gears and the drive gear mitigates excess heat produced via the frictional forces which tend to arise in conventional equipment.

Beneficially, said meshing contributes to passive temperature control.

Alternatively, the drive gear and the one or more driven gears may indirectly engage other. For example, the transmission arrangement may further comprise a drive belt, drive chain, pulley mechanism or the like. The drive gear and the one or more driven gears may be coupled via said drive belt, drive chain, pulley mechanism or the like, such that rotation of the drive gear drives the one or more driven gears via the drive belt, drive chain, pulley mechanism or the like.

The transmission arrangement may be configured so that rotation of the drive gear will cause the one or more driven gears to process around the drive gear. The transmission arrangement may be configured and/or operable so that rotation of the drive gear in a first rotational direction may cause the one or more driven gears to process around the drive gear in the same first rotational direction. The transmission arrangement may be configured and/or operable so that rotation of the drive gear in the first rotational direction may cause the one or more driven gears to rotate about a second, opposite, rotational direction. The one or more driven gears may rotate in the second, opposite, rotational direction about their respective longitudinal axis.

As described above, the transmission arrangement comprises one or more driven gears, said one or more driven gears forming planet gears of the transmission arrangement, and wherein at least one of said driven gears forms or is configured to receive therein the receptacle for receiving the material to be ground and the grinding media.

The apparatus may comprise a single driven gear.

In particular embodiments, however, the apparatus may comprise a plurality of the driven gears.

The provision of a plurality of the driven gears, each forming a receptacle or having a receptacle received therein provides a number of significant benefits.

For example, the provision of a plurality of driven gears, each forming a receptacle or having a receptacle received therein permits the grinding of more material at the same time, facilitating greater throughput of material. Alternatively or additionally, the apparatus may facilitate the grinding of different materials at the same time, thereby increasing the flexibility of the apparatus. Alternatively or additionally, the apparatus may permit a user to select the number of receptacles to be used during a given operation simply by choosing the appropriate number of driven gears This may greatly increase the flexibility of the apparatus.

The apparatus may, for example. comprise between two and fifty driven gears. However, it will be understood that the apparatus may comprise any suitable number of driven gears.

The plurality of driven gears may be arranged in a single layer.

Alternatively, the plurality of driven gears may be arranged in two or more layers.

For example, the number of layers of driven gears that may be accommodated within the apparatus may depend upon the size, e.g. the internal volume, of the driven gears. For example, driven gears having an internal volume of 2 to 3 millilitres may be useful for optimising chemical reactions. A reduction in the internal volume of the driven gears would allow for a greater number of driven gears to be stacked one on top of the other, e.g. four or five layers of driven gears. In some instances this may facilitate 50 or more samples to be milled at once.

Alternatively or additionally, the number of layers of driven gears that may be accommodated within the apparatus may depend upon the internal volume of the ball mill apparatus. Such adaptability of the ball mill apparatus results in the potential for the apparatus to achieve varying degrees of throughput greater than those achievable by conventional devices.

The apparatus may comprise a plurality of driven gears from which a given driven gear or set of driven gears may be selected. For example, the apparatus may comprise a first driven gear or set of driven gears and at least one additional driven gear or set of driven gears. The at least one additional driven gear or set of driven gears may have a different configuration to the first driven gear or set of driven gears.

The driven gear or gears of the at least one additional driven gear or set of driven gears may, for example but not exclusively, have: a different outer diameter; different number of teeth; different profiles; and/or may be constructed from different materials to the first driven gear or set of driven gears.

The one or more driven gears may comprise or take the form of spur gears.

Alternatively, the one or more driven gears may comprise or take the form of helical gears.

Beneficially, forming the one or more driven gears as a spur gear or helical gear permits the driven gear to be slid into place to mesh with the drive gear, facilitating ease of insertion and/or removal of the one or more driven gears from the apparatus.

The or each driven gear may comprise a body. The body may be hollow. The body may be cylindrical or substantially cylindrical. The body may have a base portion.

The body may have a wall portion. The wall portion may extend from the base portion. The wall portion may surround the base portion. The wall portion may define a boss portion. The boss portion may define a lip. The boss portion may define a thread profile. The thread profile may be formed on an outer surface, e.g. outer circumferential surface, of the boss portion. The body may comprise a top portion.

In embodiments where the driven gear forms the receptacle, the receptacle may be formed by or in the body. The receptacle may be formed by the base portion and the wall portion of the body.

In embodiments where the driven gear is configured to receive the receptacle, the body may define the recess or bore portion for receiving the receptacle.

At least one of the driven gears may be constructed from a metal or metallic material. For example, at least one of the driven gears may be constructed from steel, e.g. stainless steel, or aluminium alloy.

Alternatively or additionally, the driven gears may be constructed from other suitable materials, such as a ceramic material, a composite material, a plastic material, or a combination of these. For example, at least one of the driven gears may be constructed from polytetrafluoroethylene (PT FE) or polypropylene.

Beneficially, constructing the driven gears from a non-metallic material such as polytetrafluoroethylene (PTFE) or polypropylene (PP) may reduce the noise levels generated by the grinding process, facilitating quieter operation and/or reducing the generation of frictional heat.

At least one of the driven gears may comprise a cap.

The cap may be configured for mounting on the driven gear. The cap may be configured for mounting to the top portion of the driven gear. The cap may be configured for mounting to the driven gear, e.g. the top portion of the driven gear, via a thread connection.

The cap may comprise a boss portion. The boss portion may define a thread profile. The thread profile may be formed on an inner surface, e.g. inner circumferential surface, of the boss portion. The thread profile may be configured to engage the thread profile of the boss portion of the body of the driven gear, so as to facilitate securement of the cap to the body.

However, it will be understood that other means for securing the cap to the body may be provided. For example, the cap may be secured to the body via a push fit or interference fit coupling or may be hingedly coupled to the body. Alternatively, the cap and the body of the driven member may be integrally formed.

The cap may comprise a groove. A seal member may be provided, in particular an annular seal member such as an o-ring seal member. The groove may be configured to receive the seal member.

The cap may be constructed from a metal or metallic material. For example, the cap may be constructed from Aluminium alloy. However, it will be understood that the cap may be constructed from other suitable materials, such as a ceramic material, a composite material or a plastic material.

The cap may comprise a valve. The valve may be configured and/or operable to permit the atmosphere within the driven gear to be regulated.

The cap may comprise a sensor arrangement. The sensor arrangement may comprise one or more temperature sensors. The sensor arrangement may comprise one or more pressure sensors. The sensor arrangement may be configured and/or operable to monitor the atmosphere within the driven gear.

As described above, the transmission arrangement comprising a drive gear, wherein the drive gear defines a sun gear of the transmission arrangement.

The drive gear may comprise or take the form of a spur gear.

Alternatively, the drive gear may comprise or take the form of a helical gear.

Beneficially, forming the drive gear as a spur gear or helical gear permits the one or more driven gears to be slid into place to mesh with the drive gear, facilitating ease of insertion and removal of the one or more driven gears from the apparatus.

The drive gear may comprise a body. The body may be cylindrical or substantially cylindrical. The body may be annular.

The body may comprise a bore, e.g. an axial bore. In particular embodiments, the bore may extend wholly through the body, i.e. the bore may be a throughbore. Alternatively, the bore may extend partially through the body.

The bore may be configured to receive a drive shaft of the rotary drive arrangement. The bore may define a key profile. The key profile may be configured to engage a corresponding key profile on the drive shaft of the rotary drive arrangement.

The apparatus may comprise a plurality of drive gears from which a given drive gear for use in the apparatus is selected.

In use, the drive gear may be interchangeable.

For example, the apparatus may comprise a first drive gear and at least one additional drive gear, the at least one additional drive gear having a different configuration to the first drive gear. The at least one additional drive gear may for example but not exclusively have: a different outer diameter; a different number of teeth; a different profile; and/or may be constructed from a different material to the first drive gear.

The ability to select a drive gear from a plurality of drive gears provides a number of benefits. For example, the selection of a drive gear having a larger outer diameter, for example permits an increased number of driven gears to be used. An increased number of driven gears increases the number of different materials which can be ground at the same time, thereby increasing the flexibility of the apparatus. Alternatively or additionally, the ability to adapt the number of driven gears allows the user to alter the gear ratio. As the motion of the grinding media, e.g. grinding balls, within the receptacles is influenced by the gear ratio, the user can alter the level of energy transferred to the material being ground, thereby increasing the flexibility of the apparatus.

The drive gear may be constructed from a metal or metallic material. For example, the drive gear may be constructed from steel, e.g. stainless steel, or aluminium alloy.

Alternatively or additionally, the drive gear may be constructed from other suitable materials, such as a ceramic material, a composite material, a plastic material, or a combination of these. For example, the drive gear may be constructed from polytetrafluoroethylene (FIFE) or polypropylene.

Beneficially, constructing the drive gear from a non-metallic material such as polytetrafluoroethyiene (RITE) or polypropylene (PP) may reduce the noise levels generated by the grinding process, facilitating quieter operation and/or reducing the generation of frictional heat.

The drive gear and/or at least one of the driven gears may be detachable from the apparatus.

The drive gear may be detachably coupled to the rotary drive arrangement. For example, the drive gear may be keyed to a drive shaft of the rotary drive arrangement.

The drive gear may be slidably engageable with the rotary drive arrangement. The drive gear may be slidably engageable with the one or more driven members.

Beneficially, the provision of a drive gear which is slidably engageable with the rotary drive arrangement and/or driven gears permits the drive gear to be easily inserted and/or removed from the apparatus.

The at least one driven gear may be slidably engageable with the drive gear.

Beneficially, the provision of one or more driven gear which is slidably engageable with the drive gear permits the drive gear to be easily inserted and/or removed from the apparatus.

The apparatus may comprise a ring gear.

The ring gear may be configured to surround the one or more driven gears.

The ring gear may be configured to engage and mesh with the one or more driven gears, such that rotation of the drive gear drives rotation of the one or more driven gears and causes said one or more driven gears to process around the inside of the ring gear.

Where the apparatus comprises at least one detachable driven gear, the at least one driven gear may be slidably engageable with the ring gear.

The ring gear may comprise a gear tooth profile. The gear tooth profile may be formed on an inner circumferential surface of the ring gear. The gear tooth profile may comprise or take the form of a spur gear tooth profile. Alternatively, the gear tooth profile may comprise or take the form of a helical gear tooth profile.

Beneficially, forming the gear tooth profile of the ring gear as a spur gear profile or helical gear profile permits the one or more driven gears to be slid into place to mesh with the ring gear, facilitating ease of insertion and removal of the one or more driven gears from the apparatus.

The ring gear may be static, i.e. the ring gear may be fixed relative to the driven gears The ring gear may define a housing of the transmission arrangement of the apparatus.

Beneficially, the cylindrical form of the ring gear may facilitate passive heat dissipation from the apparatus, preventing or at least mitigating the risk of overheating and the consequential reduction in performance, throughput and/or operational lifetime of the apparatus. The cylindrical design may also act as a very effective heatsink, allowing frictional heat to be expelled into the environment, e.g. by a fan. The apparatus thus permits one or both of passive and active heat transfer away from the apparatus, maintaining the temperature at manageable levels during operation. This in turn means that milling operation does not need to be paused at intervals in order to permit the apparatus and/or the material sample to cool down.

In particular embodiments, the ring gear may be configured to facilitate transfer of heat away from the ring gear. The ring gear may comprise one or more cooling fins. The cooling fins may be integral and/or coupled to an exterior surface of the ring gear. The one or more cooling fins may be constructed from a metal or metallic material for

example.

Beneficially, the one or more cooling fins expel frictional heat into the environment.

Alternatively, the ring gear may comprise a separate member disposed within a housing of the apparatus.

In particular embodiments, the transmission arrangement of the apparatus may comprise a single drive gear, a plurality of driven gears disposed around the outside of the drive gear, and a single ring gear disposed around the outside of the driven gears.

The apparatus may be configured so that the milling conditions may be monitored, for example with the use of spectroscopy, for example Raman spectroscopy, X-ray, neutron diffraction and/or other suitable techniques. In particular embodiments, the ring gear may comprise an inlet. The inlet may be formed through the wall of the ring gear. The ring gear may comprise an outlet. The outlet may be formed through the wall of the ring gear. The inlet and the outlet are circumferentially offset from each other.

In use, a source may be configured and/or operable to direct a beam, for example a laser beam, X-ray beam or neutron beam, through the inlet. The beam passes through the driven gear and interacts with the sample. The beam then exits through the outlet, where it is received by a detector.

Beneficially, this permits milling conditions to be monitored.

The ring gear may be constructed from a metal or metallic material. For example, the ring gear may be constructed from steel, e.g. stainless steel, or aluminium alloy.

Alternatively or additionally, the ring gear may be constructed from other suitable materials, such as a ceramic material, a composite material, a plastic material, or a combination of these. For example, the ring gear may be constructed from polytetrafluoroethylene (FIFE) or polypropylene.

Beneficially, constructing the ring gear from a non-metallic material such as polytetrafluoroethylene (PTFE) or polypropylene (PP) may reduce the noise levels generated by the grinding process, facilitating quieter operation and/or reducing the generation of frictional heat.

The ring gear may comprise a chamber. For example, at least part of the ring gear may be hollow. The chamber may be couplable to and/or configured to communicate with a heating arrangement or cooling arrangement to facilitate heating and/or cooling of the apparatus.

The apparatus may comprise a lid.

The lid may be disposed on and/or configured for coupling to an upper surface of the ring gear.

Alternatively or additionally, the lid may be disposed on and/or configured for coupling to the housing.

The lid may be coupled to the ring gear and/or the housing by any suitable means. For example, the lid may be coupled to the ring gear and/or the housing by one or more fasteners, such as butterfly fasteners, screws, bolts or the like. Alternatively or additionally, the lid may be coupled to the ring gear and/or the housing by a thread connection. Alternatively or additionally, the lid may be coupled to the ring gear and/or the housing by an interference fit connection.

The lid may comprise a seal element. The seal element may be disposed in a groove formed or otherwise provided in the lid.

The seal element may comprise or take the form of an o-ring.

10 15 20 The seal element may be configured and/or operable to provide an airtight seal between the lid and the ring gear or housing.

The lid may comprise one or more openings.

At least one of the openings may be configured (e.g. positioned, sized and/or shaped) to facilitate ventilation of the interior of the apparatus, for example to transport heat away from the apparatus. Alternatively, at least one of the openings may be configured (e.g. positioned, sized and/or shaped) to facilitate heating of the interior of the apparatus. For example, the at least one opening configured (e.g. positioned, sized and/or shaped) to facilitate heating of the interior of the apparatus may be coupled to or operatively associated with a heating arrangement. Alternatively or additionally, at least of the openings may be coupled to or operatively associated with one or more measurement instrument, sensor arrangement.

The apparatus may comprise a magnet arrangement. The magnet arrangement may comprise a magnet arranged on or in at least one of the driven gears, e.g. on or in the base portion of the body of the driven gear. The magnet arrangement may comprise a magnet provided below the one or more driven gears, e.g. on or in a support plate of the apparatus.

The magnet arrangement may be configured (e.g. the poles of the magnet arranged on or in at least one of the driven gears and the magnet below the one or more driven gears may be selected so that they are opposed and have sufficient magnetic strength) to levitate the one or more driven gears.

Beneficially, the magnet arrangement may reduce the noise levels generated by the grinding process, facilitating quieter operation and/or reducing the generation of frictional heat.

The apparatus may comprise a lubrication arrangement. The lubrication arrangement may comprise a lubricant layer applied to or adhered to the at least one of the driven gears and/or the drive gear.

Beneficially, the lubrication arrangement may reduce the noise levels generated by the grinding process, facilitating quieter operation and/or reducing the generation of frictional heat.

As described above, the apparatus comprises a rotary drive arrangement configured to drive rotation of the drive gear.

The rotary drive arrangement may comprise or take the form of a motor. The motor may comprise or take the form of an electric motor.

A drive shaft of the rotary drive arrangement may be coupled to or operatively associated with the drive gear. The rotary drive arrangement may be directly coupled to the drive gear.

The apparatus may comprise a communication arrangement. The communication arrangement may be configured and/or operable to communicate with one or more remote location. The communication arrangement may comprise or take the form of a transmitter or transceiver.

The communication arrangement may comprise or take the form of a wireless communication arrangement. For example, the apparatus may comprise a wireless communication arrangement. The wireless communication arrangement may comprise a radio frequency communication arrangement. The wireless communication arrangement may be configured and/or operable to communicate via Wi-Fi, Bluetooth, Zigbee, internet connection or other similar wireless connection.

The remote location may comprise or take the form of a mobile device such as tablet, mobile phone or the like. Alternatively or additionally, the remote location may comprise or take the form of a control room. Alternatively or additionally, the remote location may comprise or take the form of a data store, such as an online data store.

The communication arrangement may comprise or take the form of a wired communication arrangement. The wired communication arrangement may comprise or take the form of an electric wire and/or optical fibre communication arrangement.

The apparatus may comprise an onboard human machine interface (HMI), e.g. a display, a control panel, e.g. comprising buttons, switches or the like. However, in particular embodiments the apparatus may not comprise an onboard human machine interface (HMI), the wireless communication arrangement permitting control of the apparatus by a user.

Beneficially, providing an apparatus which does not have a human machine interface (HMI) facilitates use of the apparatus in a cryogenic milling system.

The apparatus may comprise an enclosure. The planetary gear arrangement may be disposed on top of the enclosure.

The enclosure may define a housing for the rotary drive arrangement, the fan and/or the electronics module.

The apparatus may comprise, may be coupled to, or operatively associated with, a heating arrangement.

The heating arrangement may be configured and/or operable to increase the temperature of the material sample(s) during the milling process.

Beneficially, the ball mill apparatus is capable of facilitating a more efficient milling process. The increase in the temperature of the milling samples during the milling process results in the milling samples undergoing the desired chemical reactions in less time relative to that of which conventional devices are capable of facilitating. Accordingly, the reduction in milling time results in an increase in the level of throughput of the apparatus. Furthermore, the ability to facilitate the milling of samples at far higher temperatures increases the utility of the apparatus, as it becomes capable of facilitating an increased range of chemical reactions.

The heating arrangement may comprise or take the form of a heat gun, in particular a temperature controlled heat gun.

In use, the heating arrangement may be utilised to direct hot air towards the drive gear, which is then transmitted to the one or more driven gears.

The heating arrangement may, for example, be coupled to or otherwise arranged relative to an opening in the lid of the apparatus, so as to direct the heat into the apparatus.

The drive gear may comprise one or more openings in its circumferential surface to facilitate the transfer of the heat to the one or more driven members.

Alternatively or additionally, the heating arrangement may comprise one or more heating elements. The heating elements may be located within the enclosure of the apparatus.

The apparatus may comprise, may be coupled to, or operatively associated with, a cooling arrangement.

The cooling arrangement may be configured and/or operable to decrease the temperature of the material sample(s) during the milling process.

The apparatus may comprise or may be coupled to a conduit system, in particular a fluid conduit system. The conduit system may be configured and/or operable to direct and/or circulate a coolant, e.g. cryogenic medium, to and/or from the apparatus.

The coolant may comprise or take the form of a cryogenic medium. The coolant may comprise or take the form of a source of a coolant fluid. The coolant fluid may comprise or take the form of a cryogenic fluid. In particular embodiments, the coolant fluid may comprise or take the form of liquid nitrogen. Alternatively, the coolant fluid may comprise or take the form of a refrigerant, such as Freon or water.

Alternatively, the coolant may comprise or take the form of a solid material. For example, the coolant may comprise or take the form of solid carbon dioxide, commonly known as dry ice.

The apparatus may comprise, may be coupled to or operatively associated with a pump.

The pump may be configured and/or operable to direct the coolant to and/or from the apparatus.

The apparatus may comprise insulation, e.g. insulation member, disposed between the planetary gear arrangement and the enclosure.

Beneficially, the insulation inhibits heat transfer between the transmission arrangement and the enclosure, acting to protect the components, in particular electronic components, disposed therein.

According to a second aspect, there is provided a planetary ball mill apparatus, comprising: a transmission arrangement comprising: a drive member, wherein the drive member defines a sun of the transmission arrangement; and one or more driven members, wherein the one or more driven members form planets of the transmission arrangement, wherein the transmission arrangement is configured such that rotation of the drive member drives rotation of the one or more driven members; and a rotary drive arrangement configured to drive rotation of the transmission arrangement, wherein at least one of said driven members forms a receptacle for receiving a material to be ground and a grinding media.

The receptacle and the driven member may be integrally formed or form a unitary construction. The driven member may comprise a first portion which operatively forms part of the transmission arrangement and a second, container, portion suitable for holding the material to be ground and the grinding media and which defines the receptacle.

The first portion may comprise or define: a toothed portion; a wheel, e.g. a pulley wheel or the like. The first portion may be configured to directly engage the drive member. Alternatively, the first portion may indirectly engage the drive member, e.g. via a belt, chain or the like.

According to a third aspect, there is provided a milling system, comprising: the apparatus of the first aspect or the second aspect; and a container.

The container may comprise or take the form of an insulated container.

The system may comprise or may be coupled to a heating arrangement.

The system may comprise or may be coupled to a cooling arrangement.

The container may comprise, may be coupled to or configured to receive a coolant.

The coolant may comprise or take the form of a cryogenic medium. The coolant may comprise or take the form of a source of a coolant fluid. The coolant fluid may comprise or take the form of a cryogenic fluid. In particular embodiments, the coolant fluid may comprise or take the form of liquid nitrogen. Alternatively, the coolant fluid may comprise or take the form of a refrigerant, such as Freon or water.

The system may comprise or may be coupled to a conduit system, in particular a fluid conduit system. The conduit system may be coupled to and communicate with an interior of the container. The conduit system may be configured and/or operable to direct the coolant, e.g. cryogenic medium, to and/or from the container.

The system may comprise or may be coupled to a pump.

The pump may be configured and/or operable to direct the coolant to and/or from the apparatus Alternatively, the coolant may comprise or take the form of a solid material. For example, the coolant may comprise or take the form of solid carbon dioxide, commonly known as dry ice.

According to a fourth aspect, there is provided a milling method using the apparatus of the first aspect, the apparatus of the second aspect or the system of the third aspect.

The apparatus or any aspect defined herein, or any individual component or groups of components, may be manufactured in any suitable manner. In some examples the disclosed apparatus, or any individual component or groups of components may be manufactured by additive manufacturing. Such described additive manufacturing typically involves processes in which components are fabricated based on three-dimensional (3D) information, for example a three-dimensional computer model (or design file), of the component.

Accordingly, examples described herein not only include the apparatus and associated components, but also methods of manufacturing the apparatus or associated components via additive manufacturing and computer software, firmware or hardware for controlling the manufacture of the apparatus and associated components via additive manufacturing. All future reference to "product" are understood to include the described apparatus and all associated components.

The structure of the product may be represented digitally in the form of a design file. A design file, or computer aided design (CAD) file, is a configuration file that encodes one or more of the surface or volumetric configuration of the shape of the product. That is, a design file represents the geometrical arrangement or shape of the product.

Design files may take any now known or later developed file format. For example, design files may be in the Stereolithography or "Standard Tessellation Language" (.stl) format which was created for stereolithography CAD programs of 3D Systems, or the Additive Manufacturing File (.amf) format, which is an American Society of Mechanical Engineers (ASME) standard that is an extensible markup-language (XML) based format designed to allow any CAD software to describe the shape and composition of any three-dimensional object to be fabricated on any additive manufacturing printer.

Further examples of design file formats include AutoCAD (.dwg) files, Blender (.blend) files, Parasolid (.x t) files, 3D Manufacturing Format (.3mf) files, Autodesk (3ds) files, Collada (.dae) files and Wavefront (.obj) files, although many other file formats exist.

Design files may be produced using modelling (e.g. CAD modelling) software and/or through scanning the surface of a product to measure the surface configuration of the product.

Once obtained, a design file may be converted into a set of computer executable instructions that, once executed by a processer, cause the processor to control an additive manufacturing apparatus to produce a product according to the geometrical arrangement specified in the design file. The conversion may convert the design file into slices or layers that are to be formed sequentially by the additive manufacturing apparatus. The instructions (otherwise known as geometric code or "G-code") may be calibrated to the specific additive manufacturing apparatus and may specify the precise location and amount of material that is to be formed at each stage in the manufacturing process. The formation may be through deposition, through sintering, or through any other form of additive manufacturing method.

The code or instructions may be translated between different formats, converted into a set of data signals and transmitted, received as a set of data signals and converted to code, stored, etc., as necessary. The instructions may be an input to the additive manufacturing system and may come from a part designer, an intellectual property (IP) provider, a design company, the operator or owner of the additive manufacturing system, or from other sources. An additive manufacturing system may execute the instructions to fabricate the product using any of the technologies or methods disclosed herein.

Design files or computer executable instructions may be stored in a (transitory or non-transitory) computer readable storage medium (e.g., memory, storage system, etc.) storing code, or computer readable instructions, representative of the product to be produced. As noted, the code or computer readable instructions defining the product that may be used to physically generate the object, upon execution of the code or instructions by an additive manufacturing system. For example, the instructions may include a precisely defined 3D model of the product and may be generated from any of a large variety of well-known computer aided design (CAD) software systems such as AutoCADO, TurboCADO, DesignCAD 3D Max, etc. Alternatively, a model or prototype of the component may be scanned to determine the three-dimensional information of the component.

Accordingly, by controlling an additive manufacturing apparatus according to the computer executable instructions, the additive manufacturing apparatus may be instructed to print out the product.

In light of the above, embodiments include methods of manufacture via additive manufacturing. This includes the steps of obtaining a design file representing the product and instructing an additive manufacturing apparatus to manufacture the product in assembled or unassembled form according to the design file. The additive manufacturing apparatus may include a processor that is configured to automatically convert the design file into computer executable instructions for controlling the manufacture of the product. In these embodiments, the design file itself may automatically cause the production of the product once input into the additive manufacturing device. Accordingly, in this embodiment, the design file itself may be considered computer executable instructions that cause the additive manufacturing apparatus to manufacture the product. Alternatively, the design file may be converted into instructions by an external computing system, with the resulting computer executable instructions being provided to the additive manufacturing device.

Given the above, the design and manufacture of implementations of the subject matter and the operations described in this specification may be realised using digital electronic circuitry, or in computer software, firmware, or hardware, including the structures disclosed in this specification and their structural equivalents, or in combinations of one or more of them. For instance, hardware may include processors, microprocessors, electronic circuitry, electronic components, integrated circuits, etc. Implementations of the subject matter described in this disclosure may be realised using one or more computer programs, i.e., one or more modules of computer program instructions, encoded on computer storage medium for execution by, or to control the operation of, data processing apparatus. Alternatively or in addition, the program instructions may be encoded on an artificially generated propagated signal, e.g., a machine-generated electrical, optical, or electromagnetic signal that is generated to encode information for transmission to suitable receiver apparatus for execution by a data processing apparatus. A computer storage medium may be, or be included in, a computer-readable storage device, a computer-readable storage substrate, a random or serial access memory array or device, or a combination of one or more of them.

Moreover, while a computer storage medium is not a propagated signal, a computer storage medium may be a source or destination of computer program instructions encoded in an artificially generated propagated signal. The computer storage medium may also be, or be included in, one or more separate physical components or media (e.g., multiple CDs, disks, or other storage devices).

Although additive manufacturing technology is described herein as enabling fabrication of complex objects by building objects point-by-point, layer-by-layer, typically in a vertical direction, other methods of fabrication are possible and within the scope of the present subject matter. For example, although the discussion herein refers to the addition of material to form successive layers, one skilled in the art will appreciate that the methods and structures disclosed herein may be practiced with any additive manufacturing technique or other manufacturing technology.

The invention is defined by the appended claims. However, for the purposes of the present disclosure it will be understood that any of the features defined above or described below may be utilised in isolation or in combination. For example, features described above in relation to one of the above aspects or below in relation to the detailed description below may be utilised in any other aspect, or together form a new aspect. In particular, features of the drive and driven gears described in relation to the first aspect may apply to the drive and driven members of the fourth aspect.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects will now be described by way of example with reference to the accompanying drawings, of which: Figure 1 shows a front perspective view of a ball mill apparatus; Figure 2 shows a side perspective view of the ball mill apparatus shown in Figure 1; Figure 3 shows another perspective view of the ball mill apparatus shown in Figure 1, with lid removed; Figure 4 shows a diagrammatic view showing components of the ball mill apparatus shown in Figure 1; Figure 5 shows a driven gear of the ball mill apparatus shown in Figure 1, with cap removed; Figure 6 shows an exploded view of the driven gear shown in Figure 5; Figure 7 shows a longitudinal sectional view of the driven gear shown in Figure 5; Figure 8 shows a cross sectional view of the cap of the driven gear; Figure 9 shows an enlarged view of part of Figure 8; Figure 10 shows a perspective view of the drive gear of the ball mill apparatus shown in Figure 1; Figure 11 shows a plan view of the drive gear shown in Figure 10; Figure 12 shows a longitudinal sectional view of the drive gear shown in Figure 10; Figure 13 shows a perspective view of the drive shaft of the rotary drive arrangement of the apparatus shown in Figure 1; Figure 14 show a side view of the drive shaft shown in Figure 13; Figure 15 shows a perspective view of the ring gear of the ball mill apparatus shown in Figure 1; Figure 16 shows a plan view of the ring gear shown in Figure 15; Figure 17 shows a cross sectional view of the ring gear shown in Figure 10; Figure 18 shows a perspective view of an alternative ball mill apparatus; Figure 19 shows a heating arrangement of the apparatus shown in Figure 18; Figure 20 shows a diagrammatic view of a cryogenic milling system; Figure 21 shows a diagrammatic view of an alternative cryogenic milling system; Figure 22 shows a perspective view of an alternative driven member in the form of a pulley wheel; Figures 23 and 24 show a magnet arrangement; Figures 25 and 26 show an alternative ring gear; Figure 27 shows an alternative ring gear with cooling fins integral and/or coupled to an exterior surface; Figure 28 shows an alternative ring gear comprising an inlet through an exterior surface and an outlet through an exterior surface; and Figure 29 shows a diagrammatic view showing a plurality of driven gears of the ball mill apparatus shown in Figure 1 arranged in layers.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring first to Figures 1 to 5 of the accompanying drawings, there is shown a ball mill apparatus, generally denoted 10.

As shown, the apparatus 10 comprises a transmission arrangement, generally denoted 12, which comprises a drive gear 14 and one or more driven gears 16 (the illustrated apparatus 10 comprises two driven gears 16, as shown in Figure 3). The drive gear 14 defines a sun gear of the transmission arrangement 12 and the driven gears 16 form planet gears of the transmission arrangement 12.

As shown most clearly in Figure 3, the driven gears 16 are configured for location around the drive gear 14 and configured to mesh with the drive gear 14, such that rotation of the drive gear 14 about its central longitudinal axis A drives rotation of the driven gears 16 about their respective longitudinal axes B, causing the driven gears 16 to process around the drive gear 14.

The transmission arrangement 12 is configured and/or operable so that rotation of the drive gear 14 in a first rotational direction causes the driven gears 16 to process around the drive gear 14 in the same first rotational direction. The transmission arrangement is also configured and/or operable so that rotation of the drive gear 14 in the first rotational direction causes the one or more driven gears 16 to rotate in a second, opposite, rotational direction about their respective longitudinal axes B. In the illustrated apparatus 10, the drive gear 14 and the driven gears 16 have a gear ratio of 1:1. However, it will be understood that in other embodiments the drive gear 14 and the driven gears 16 may have a gear ratio resulting in higher rotational velocity of the driven gears 16 with respect to the drive gear 14, e.g. of 1:2.

As will be described further below, each of the driven gears 16 forms a receptacle for receiving a material sample 18 to be ground and a grinding media 20 in the form of grinding balls, the driven gears 16 defining grinding jars of the apparatus 10.

As shown in Figure 4, the apparatus 10 comprises a rotary drive arrangement, generally denoted 22, configured to drive rotation of the drive gear 14. The rotary drive arrangement 22 comprises an electric motor 24 having a drive shaft 26.

In use, the material samples 18 to be ground are placed within the receptacles formed by the driven gears 16 together with the grinding media 20. The electric motor 24 drives rotation of the transmission arrangement 12 by rotating the drive gear 14 about its central longitudinal axis A, which in turn drives rotation of the driven gears 16 about their respective central longitudinal axis B. As described above, due to the planetary or epicyclic arrangement of the drive gear 14 and driven gears 16, rotation of the drive gear 14 causes the driven gears 16 to process around the drive gear 14.

The ball mill apparatus 10 provides a number of significant benefits over conventional equipment. For example, the provision of a ball mill apparatus 10 comprising driven gears 16 configured for location around the drive gear 14 and configured to mesh with the drive gear 14, wherein the driven gears 16 define the receptacles forming the grinding jars of the apparatus means that the grinding jar -and its contents in use -are aligned with (in other words in the same plane as) the drive gear 14. This results in a reduction in the asymmetric centrifugal forces experienced by the grinding jars and their contents, such that the grinding jars can operate effectively at higher rotational velocity. This in turn means that the efficiency with which the apparatus 10 grinds the material sample 18 can be improved. The alignment between the drive gear 14 and the driven gears 16 also provides a design which is also inherently safe, as any catastrophic failure will be contained within the apparatus 10.

The alignment between the drive gear 14 and the driven gears also results in a compact design, such that the apparatus 10 has a small footprint in comparison to conventional ball mill apparatus'.

Moreover, the provision of a ball mill apparatus 10 wherein the grinding jar is formed by or received within the driven gears 16 significantly simplifies the design of the ball mill apparatus 10.

As described above, the apparatus 10 comprises a plurality of the driven gears The provision of a plurality of the driven gears 16, each forming a grinding jar therein provides a number of significant benefits.

For example, the provision of a plurality of driven gears 16, each forming a grinding jar formed therein permits the grinding of more material 18 at the same time, facilitating greater throughput of material. Alternatively or additionally, the apparatus 10 facilitate the grinding of different materials at the same time, thereby increasing the flexibility of the apparatus 10 compared to conventional ball mill apparatus that can only grind one material samples at a time. Alternatively or additionally, the apparatus 10 is configured to permit a user to select the number of grinding jars to be used during a given operation simply by choosing the appropriate number of driven gears 16. This may greatly increase the flexibility of the apparatus 10 in terms of it use.

Referring now also to Figures 6 and 7 of the accompanying drawings, there is shown an exploded view and a longitudinal cross sectional view, respectively, of one of the driven gears 16 of the apparatus 10.

As shown in Figure 6, the driven gear 16 takes the form of a spur gear having a spur gear tooth profile 28 formed in its outer circumferential surface.

Beneficially, forming the driven gear 16 as a spur gear permits the driven gear 16 to be slid into place to mesh with the drive gear 14, facilitating ease of insertion and removal of the driven gear 16 from the apparatus 10. 16.

As shown in Figure 7, the driven gear 16 comprises a cylindrical body, generally denoted 30, having a base portion 32 and a wall portion 34 that extends upwards from and surrounds the base portion 32.

The wall portion 34 define a boss portion 36 defining a thread profile 38 formed on an outer circumferential surface of the boss portion 36.

In the illustrated apparatus 10, the driven gear 16 is constructed from aluminium alloy. However, it will be understood that the driven gears 16 may be constructed from other suitable materials, such as a ceramic material, a composite material, a plastic material, or a combination of these.

As shown in Figure 6, and referring now also to Figures 8 and 9 of the accompanying drawings, the driven gear 16 comprises a cap 40 configured for mounting on the boss portion 36 of the body 30 of the driven gear 16. The cap 40 comprises a boss portion 42 which defines a thread profile 44 formed on an inner circumferential surface of the boss portion 42. The thread profile 44 is configured to engage the thread profile 38, so as to facilitate securement of the cap 40 to the body 30.

However, it will be understood that other means for securing the cap 40 to the drive member 14 may be provided. For example, the cap 40 may be secured to the body 30 via a push fit or interference fit coupling or may be hingedly coupled to the body 30. Alternatively, the cap 40 and the body 30 may be integrally formed.

As shown most clearly in Figure 9, the cap 40 comprises an annular groove 46 for receiving a seal member (not shown).

In the illustrated apparatus 10, the cap 40 is constructed from aluminium alloy.

However, it will be understood that the cap 40 may be constructed from other suitable materials, such as a ceramic material, a composite material, a plastic material, or a combination of these.

As described above, the apparatus 10 comprising a drive gear 14 which defines a sun gear of the transmission arrangement 12.

Referring now also to Figures 10, 11 and 12 of the accompanying drawings, the drive gear 14 comprises a cylindrical body 48 having an axial throughbore 50 disposed therethrough. The throughbore 50 is configured to receive the drive shaft 26. The drive gear 14 takes the form of a spur gear having a spur gear tooth profile 52 formed in an outer surface of the body 48.

Beneficially, forming the drive gear 14 as a spur gear permits the driven gears 16 to be slid into place to mesh with the drive gear 14, facilitating ease of insertion and removal of the driven gears 16 from the apparatus 10.

As shown, the throughbore 50 defines a key profile 54. The key profile 54 is configured to engage a corresponding key profile 56 on the drive shaft 26.

In the illustrated apparatus 10, the drive gear 14 is constructed from aluminium alloy. However, it will be understood that the drive gear 14 may be constructed from other suitable materials, such as a ceramic material, a composite material, a plastic material, or a combination of these.

As shown in Figure 1, and referring now also to Figures 15, 16 and 17 of the accompanying drawings, the transmission arrangement 12 further comprises a ring gear, generally denoted 58, configured to surround the driven gears 16.

The ring gear 58 is configured to engage and mesh with the driven gears 16, such that rotation of the drive gear 14 drives rotation of the driven gears 16 and causes the driven gears 16 to process around the inside of the ring gear 58.

As shown, the ring gear 58 comprises an annular body 60 having a gear tooth profile 62 formed on an inner circumferential surface of the ring gear 58. The gear tooth profile 62 takes the form of a spur gear tooth profile.

Beneficially, forming the gear tooth profile 62 of the ring gear as a spur gear permits the driven gears 16 to be slid into place to mesh with the ring gear 58, facilitating ease of insertion and removal of the driven gears 16 from the apparatus 10.

The ring gear 58 is static, i.e. the ring gear 58 is fixed relative to the driven gears 16.

In the illustrated apparatus 10, the ring gear 58 defines a housing of the planetary gear arrangement 12 of the apparatus 10, together with a lid 60 (shown in Figures 1 and 2).

As shown most clearly in Figure 17, the ring gear 58 comprises bores 62 for receiving fasteners 64 for removably securing the lid 60 to the ring gear 58. In the illustrated apparatus 10, the fasteners 64 take the form of wing nuts.

Beneficially, the cylindrical form of the ring gear 58 facilitates passive heat dissipation from the apparatus 10, preventing or at least mitigating the risk of overheating and the consequential reduction in performance, throughput and/or operational lifetime of the apparatus 10. The cylindrical design may also act as a very effective heatsink, allowing frictional heat to be expelled into the environment, e.g. by a fan. The apparatus 10 thus permits one or both of passive and active heat transfer away from the apparatus 10, maintaining the temperature at manageable levels during operation. This in turn means that milling operation does not need to be paused at intervals in order to permit the apparatus 10 and/or the material sample 18 to cool down.

In the illustrated apparatus 10, the ring gear 58 constructed from aluminium alloy. However, it will be understood that the ring gear 58 may be constructed from other suitable materials, such as a ceramic material, a composite material, a plastic material, or a combination of these.

Referring again to Figure 4 of the accompanying drawings, the apparatus 10 comprises a cooling fan 66.

In use, the fan 66 moves air from the top of the apparatus 10 towards the bottom.

Beneficially, the fan 66 contributes to the expulsion of frictionally generated heat to the environment, increasing the efficiency of the milling process. Such an increase in efficiency may, e.g. be achieved by obviating the need to pause the operation of the apparatus 10 during the milling process to enable the apparatus 10 to cool down. The ability to mill uninterrupted may increase the throughput of the apparatus 10, allowing for an increased number of materials to be ground. This may in turn permit an increased number of results to be produced in a reduced amount of time.

The apparatus 10 further comprises an electronics module 68 and a communication arrangement, generally denoted 70, comprising a Bluetoothe antenna 72 (shown in Figure 1). The communication arrangement 70 is configured and/or operable to communicate with one or more remote location.

In the illustrated apparatus 10, the apparatus 10 does not comprise an onboard human machine interface (HMI), the wireless communication arrangement 70 permitting control of the apparatus 10 by a user.

Beneficially, the apparatus 10 may be controlled remotely. Moreover, providing an apparatus 10 which does not have a human machine interface (HMI) facilitates use of the apparatus 10 in a cryogenic milling system.

As shown, the apparatus 10 comprises an enclosure 74 that defines a housing for the rotary drive arrangement 22, the fan 66, the electronics module 68 and/or the communication arrangement 70 It will be understood that various modifications may be made without departing from the scope of the claimed invention.

For example, Figure 18 of the accompanying drawings shows an alternative ball mill apparatus 110. The apparatus 110 is similar to the apparatus 10 and like components are represented by like reference numerals incremented by 100.

As shown, the apparatus 110 comprises a transmission arrangement, generally denoted 112, which comprises a drive gear 114 and one or more driven gears 116 (the illustrated apparatus 110 comprises ten driven gears 116). The drive gear 114 defines a sun gear of the transmission arrangement 112 and the driven gears 116 form planet gears of the transmission arrangement 112.

The driven gears 116 are configured for location around the drive gear 114 and configured to mesh with the drive gear 114, such that rotation of the drive gear 114 about its central longitudinal axis A' drives rotation of the driven gears 116 about their respective longitudinal axes B', causing the driven gears 116 to process around the drive gear 114.

In the illustrated apparatus 110, the drive gear 114 and the driven gears 116 have a gear ratio which results in higher rotational velocity of the driven gears 116 with respect to the drive gear 114.

Each of the driven gears 116 forms a receptacle for receiving a material sample to be ground and a grinding media in the form of grinding balls, in a similar manner to that described above with respect to the apparatus 10.

The transmission arrangement 112 further comprises a ring gear 158 configured to surround the driven gears 16 As shown in Figure 18, the apparatus 110 differs from the apparatus 10 in that the drive gear 114 takes the form of a ring gear with spur gear tooth profile 152 formed in an outer surface of body 148.

The apparatus 110 comprise a heating arrangement configured and/or operable to increase the temperature of the material sample(s) during the milling process.

The heating arrangement may comprise or take the form of a heat gun 174, in particular a temperature controlled heat gun.

The heat gun is coupled to or otherwise arranged relative to an opening 176 in the lid 160 of the apparatus 110, so as to direct the heat into the apparatus 110.

In use, the heating gun 174 may be utilised to direct hot air towards the drive gear 114, which is then transmitted to the driven gears 116 and their contents.

Beneficially, the ball mill apparatus 110 is capable of facilitating a more efficient milling process. The increase in the temperature of the milling samples during the milling process results in the milling samples undergoing the desired chemical reactions in less time relative to that of which conventional devices are capable of facilitating. Accordingly, the reduction in milling time results in an increase in the level of throughput of the apparatus 110. Furthermore, the ability to facilitate the milling of samples at far higher temperatures increases the utility of the apparatus 110, as it becomes capable of facilitating an increased range of chemical reactions.

Figure 20 of the accompanying drawings shows a cryogenic milling system, generally denoted 1000.

As shown in Figure 20, the system 1000 comprises the apparatus 10 disposed within an insulated container 1002. It will be recognised that the system 1000 may comprise any ball mill apparatus according to the present disclosure. The container 1002 is configured to receive a cryogenic source 1004, which in the illustrated system 1000 take the form of solid carbon dioxide, commonly known as dry ice.

Figure 21 of the accompanying drawings shows an alternative cryogenic milling system, generally denoted 2000.

As shown in Figure 21, the system 2000 comprises a source 2002 of cryogenic liquid, which in the illustrated system 2000 takes the form of liquid nitrogen, connected to the apparatus 110 via a fluid conduit system 2004, e.g. a cryogenic hose or the like, and a pump 2006 for directing the cryogenic liquid from the source 2002 to the apparatus 110. It will be recognised that the system 2000 may comprise any ball mill apparatus according to the present disclosure.

As described above, it will be understood that various modifications may be made without departing from the scope of the claimed invention.

For example, an alternative transmission arrangement is shown in Figure 22.

As shown in Figure 22, in place of the drive gear 14, 114 and driven gears 16, 116 described above, the transmission arrangement comprises drive and driven members in the form of pulley wheels, generally denoted 214 and 216 (one driven member 216 is shown for clarity).

The drive member 214 is fixedly coupled to a linkage 268 (shown in dotted lines for clarity) such that rotation of the drive member 214 also rotates the linkage 268. The driven members 216 are rotatably mounted in the linkage 268, such that the rotation of the linkage 268 by the drive member 214 causes the driven member 216 to rotate around the drive member 214 in a planetary fashion.

The drive member 214 and the driven members 216 are coupled via a drive belt 270, such that rotation of the drive member 214 is also transmitted to the driven members 216 via the belt 270, causing the driven members 216 to rotate about their central longitudinal axis.

As shown in Figure 22, the driven member 216 is similar to the driven members 16, 116 and forms a receptacle (also shown in dotted lines) therein for receiving the material to be ground and a grinding media.

Providing receptacles which are formed by the driven members 216 means that the receptacles -and their contents in use -are aligned with, substantially aligned with or at least partially aligned with On other words in the same plane as) the drive member 214. This results in a reduction in the asymmetric centrifugal forces experienced by the receptacles and their contents, such that the receptacles can operate effectively at higher rotational velocity. This in turn means that the efficiency with which the apparatus grinds the material to be ground can be improved. The alignment between the drive member and the driven members also provides a design which is also inherently safe, as any catastrophic failure will be contained within a housing of the apparatus. The alignment between the drive member and the driven members also results in a compact design, such that the apparatus has a small footprint in comparison to conventional ball mill apparatus'. Moreover, the provision of a ball mill apparatus wherein the receptacles are formed by or received within the driven members significantly simplifies the design of the ball mill apparatus.

Figures 23 and 24 of the accompanying drawings show a magnet arrangement, generally denoted 172, for reducing the noise levels generated by the grinding process, facilitating quieter operation and/or reducing the generation of frictional heat.

As shown, the magnet arrangement 172 is illustrated as part of the apparatus 110. However, it will be understood that the magnet arrangement 172 may be utilised in any apparatus according to the present disclosure.

As shown in Figures 23 and 24, the magnet arrangement 172 comprises magnets 174 provided in a support plate 176 of the apparatus 110, the number of magnets 172 corresponding to the number of driven gears 116 that can be accommodated in the apparatus 110. A magnet 178 is also provided in or on a bottom surface of each of the driven gears 116.

The magnets 174,178 are configured so that their poles and magnetic strength result in the driven gears 116 levitating above the support plate 176.

Beneficially, the magnet arrangement 172 reduce the noise levels generated by the grinding process, facilitating quieter operation and/or reducing the generation of frictional heat.

Figures 25 and 26 show an alternative ring gear 358.

As shown, the ring gear 358 is illustrated as part of the apparatus 110.

However, it will be understood that the ring gear 358 may be utilised in any apparatus

according to the present disclosure.

In the illustrated form, the ring gear 358 is hollow, having a chamber 380 which couplable to and/or configured to communicate with a heating arrangement or cooling arrangement to facilitate heating and/or cooling of the apparatus.

Figure 27 shows an alternative ring gear 458 which is configured to facilitate the transfer of heat away from the ring gear 458. The ring gear 458 comprises one or more cooling fins 482. The cooling fins 482 are integral and/or coupled to an exterior surface 484 of the ring gear 458. The one or more cooling fins 482 may be constructed from a metal or metallic material for example. It will be understood that the ring gear 458 may be utilised in any apparatus according to the present disclosure.

Beneficially, the one or more cooling fins 482 expel frictional heat into the environment The apparatus 10, 110 may be configured so that the milling conditions may be monitored, for example with the use of spectroscopy, for example Raman spectroscopy, X-ray, neutron diffraction and/or other suitable techniques.

Figure 28 shows an alternative ring gear 558. The ring gear 558 comprises an inlet 586. The inlet 586 is formed through a wall 588 of the ring gear 558. The ring gear 558 comprises an outlet 590. The outlet 590 is formed through the wall 588 of the ring gear 558. The inlet 586 and the outlet 590 are circumferentially offset from each other.

In use, a source 592 is configured and/or operable to direct a beam 594, for example a laser beam, X-ray beam or neutron beam, through the inlet 586. The beam 594 passes through the driven gear 16, 116 and interacts with the sample 18, 118. The beam 594 then exits through the outlet 590, where it is received by a detector 596.

Figure 29 shows a diagrammatic view showing a plurality of driven gears 16 of the ball mill apparatus 10 shown in Figure 1 arranged in layers. However, it will be understood that the plurality of driven gears 16 may be arranged in layers in any apparatus according to the present disclosure.

For example, the number of layers of driven gears 16 that may be accommodated within the apparatus 10 may depend upon the size, e.g. the internal volume, of the driven gears 16. For example, driven gears 16 having an internal volume of 2 to 3 millilitres may be useful for optimising chemical reactions. A reduction in the internal volume of the driven gears 16 would allow for a greater number of driven gears 16 to be stacked one on top of the other, e.g. 4 or 5 layers of driven gears 16. In some instances, this may facilitate 50 or more samples 18 to be milled at once.

Alternatively or additionally, the number of layers of driven gears 16 that may be accommodated within the apparatus 10 may depend upon the internal volume of the ball mill apparatus 10. Such adaptability of the ball mill apparatus 10 results in the potential for the apparatus 10 to achieve varying degrees of throughput greater than those achievable by conventional devices.

Claims (25)

1. CLAIMS1. A planetary ball mill apparatus, comprising: a transmission arrangement comprising: a drive gear, wherein the drive gear defines a sun gear of the transmission arrangement; and one or more driven gears, wherein the one or more driven gears form planet gears of the transmission arrangement; and a rotary drive arrangement configured to drive rotation of the transmission arrangement, wherein at least one of said driven gears forms or is configured to receive therein a receptacle for receiving a material to be ground and a grinding media.
2. 2. The apparatus of claim 1, wherein, when said at least one driven gear forms the receptacle, said at least one driven gear comprises a first, geared, portion which operatively forms part of the transmission arrangement and a second, container, portion suitable for holding the material to be ground and the grinding media and which defines the receptacle.
3. 3. The apparatus of claim 1, wherein, when said at least one driven gear is configured to receive therein the receptacle, said at least one driven gear comprises a first portion which defines a gear profile which operatively forms part of the transmission arrangement and a second, recess or bore, portion suitable for receiving at least part of the receptacle.
4. 4. The apparatus of claim 1, 2 or 3, wherein the drive gear and the one or more driven gears are directly engaged.
5. 5. The apparatus of claim 1, 2 or 3, wherein the drive gear and the one or more driven gears indirectly engage other.
6. 6. The apparatus of claim 5, wherein the transmission arrangement further comprises a drive belt, drive chain, or pulley mechanism, the drive gear and the one or more driven gears being coupled via said drive belt, drive chain, or pulley mechanism such that rotation of the drive gear drives the one or more driven gears via the drive belt, drive chain, or pulley mechanism.
7. 7. The apparatus of any preceding claim, comprising a plurality of the driven gears
8. 8. The apparatus of claim 7, wherein the driven gears are arranged in two or more layers.
9. 9. The apparatus of claim 7 or 8, wherein the apparatus comprises a plurality of driven gears from which a given driven gear or set of driven gears is selected.
10. 10. The apparatus of any preceding claim, wherein the drive gear and the one or more driven gears comprise or take the form of spur gears.
11. 11. The apparatus of any one of claims 1 to 9, wherein the drive gear and the one or more driven gears comprise or take the form of helical gears.
12. 12. The apparatus of any preceding claim, comprising a ring gear, wherein the ring gear is configured to surround the one or more driven gears.
13. 13. The apparatus of claim 12, wherein the ring gear defines a housing of the transmission arrangement of the apparatus. 25
14. 14. The apparatus of any preceding claim, wherein at least one of: the apparatus comprises, is coupled to or is operatively associated with a heating arrangement; the apparatus comprises, is coupled to or is operatively associated with a cooling arrangement.
15. 15. The apparatus of claim 14, when dependent on claim 12, wherein the ring gear comprises a chamber, the chamber being couplable to and/or configured to communicate with the heating arrangement and/or cooling arrangement.
16. 16. The apparatus of any preceding claim, comprising a magnet arrangement, wherein the magnet arrangement comprises a magnet arranged on or in at least one of the driven gears and a magnet below the one or more driven gears.
17. 17. A planetary ball mill apparatus, comprising: a transmission arrangement comprising: a drive member, wherein the drive member defines a sun of the transmission arrangement; and one or more driven members, wherein the one or more driven members form planets of the transmission arrangement, wherein the transmission arrangement is configured such that rotation of the drive member drives rotation of the one or more driven members; and a rotary drive arrangement configured to drive rotation of the transmission arrangement, wherein at least one of said driven members forms a receptacle for receiving a material to be ground and a grinding media.
18. 18. The apparatus of claim 17, wherein said at least one driven member comprises a first portion which operatively forms part of the transmission arrangement and a second, container, portion suitable for holding the material to be ground and the grinding media and which defines the receptacle.
19. 19. The apparatus of claim 18, wherein the first portion comprises or defines: a toothed portion; a wheel, e.g. a pulley wheel.
20. 20. The apparatus of claim 17, 18 or 19, wherein the drive member and the one or more driven members are directly engaged.
21. 21. The apparatus of claim 17, 18 or 19, wherein the drive member and the one or more driven members indirectly engage other.
22. 22. The apparatus of claim 21, wherein the transmission arrangement further comprises a drive belt, drive chain, or pulley mechanism, the drive member and the one or more driven members being coupled via said drive belt, drive chain, or pulley mechanism such that rotation of the drive member drives the one or more driven members via the drive belt, drive chain, or pulley mechanism.
23. 23. A milling system comprising: the apparatus of any preceding claim; and a container.
24. 24. The system of claim 23, wherein the system comprises or is coupled to a heating arrangement and/or a cooling arrangement.
25. 25. A method of milling using the apparatus of any one of claims 1 to 22 or the milling system of claim 23 or 24.