WO2007042200A1

WO2007042200A1 - Ball mill comprising means for identifying milling vessels

Info

Publication number: WO2007042200A1
Application number: PCT/EP2006/009640
Authority: WO
Inventors: Markus Bund; Wolfgang Mutter; Gerhard BÄR; Egbert Huwer; Hermann Michel
Original assignee: Fritsch Gmbh
Priority date: 2005-10-07
Filing date: 2006-10-05
Publication date: 2007-04-19
Also published as: DE502006007862D1; EP1945364B1; EP1945364A1

Abstract

The aim of the invention is to operate a ball mill in a simple and secure manner and to prevent operating errors occurring on the ball mill. According to the invention, said ball mill comprises at least one receiving device for at least one milling vessel (5), which is rotationally mounted about a receiving axis, a drive (27) for the receiving device, at least one milling vessel (5) which can be filled will milling balls and which is maintained in the receiving device when it is installed in the receiving device. Said milling vessel (5) comprises at least one readable memory device (100) whereon at least information which is specific to the milling vessel, in particular, relating to the volume and/or the material properties and/or the mass and/or the maximum rotational speed of the milling vessel, can be stored. Said ball mill also comprises a reading device (120) which is used to read at least the information from the readable memory device (100) when the milling vessel is arranged in the receiving device of the ball mill, and a control device (150) which controls the operation of the ball mill which corresponds to the read information.

Description

Ball mill with means for identifying Mahlgefaßen

The invention relates to a ball mill, in particular a planetary or centrifugal ball mill, on a laboratory scale.

In centrifugal ball mills grinding bowls are arranged eccentrically to a drive axis and move on a circular path. The rotation of a grinding bowl around its own

Axis is prevented with centrifugal ball mills. For this purpose, for example, a built-in sprocket, a Zahnradusetzung, a toothed belt, a Stangenfuhrung, a Schmidt coupling or similar device can be used, which prevent the absolute rotation of the grinding bowl.

In contrast, planetary ball mills are based on producing a combined recirculating and rotating motion for grinding bowls. As a result of the rotation of the grinding bowls, a centrifugal force directed radially outwards is exerted on the grinding stock. Unlike a centrifugal ball mill, the drive of the grinding bowls in a planetary ball mill causes absolute rotation of the grinding bowls about their own axis, the planetary axis, so that in a planetary ball mill compared to a centrifugal ball mill, a significantly larger, further centrifugal force component is produced. This is superimposed on the centrifugal component, which is generated by the circulation of the grinding bowls about the center axis.

Finally, the Coriolis effect is also effective. These three forces result in the planetary ball mill resulting force field to which the grinding balls and the material to be ground are exposed.

For certain dimensions of the rotating parts and certain rotational speeds are in one

Planetary Ball Mill generates trajectories for the grinding balls. The grinding balls then move across the grinding bowl until they impinge on the inner wall of the grinding bowl. Thereafter, the grinding balls are taken along the inner circumference of the grinding bowl until the resulting force again ensures that the above-described transverse movement takes place and the grinding balls make a flight movement through the grinding bowl. This is also referred to as "Wurfregime".

The grinding action in a ball mill depends on various parameters, including the impact of the impact of the grinding balls on the material to be ground on the Mahlbecherinnenwand. The aim of comminution by grinding with such ball mills is to produce particles of a certain fineness, that is, a desired particle size, which is smaller than the starting particle size. During comminution, particles of the starting material are broken up into smaller particles. A break occurs precisely when it succeeds in creating a critical stress field inside the particles. In addition, defects must be present in the particle in order to give rise to a fraction which continues in the particle at locally sufficiently high tensions. Due to the kinetic energy of the grinding tools, a deformation in the contact area between grinding tools and particles to be crushed is generated, which can eventually lead to breakage. Important for the comminution is the required energy input into the volume to be shredded as a mechanical work, which is to spend until reaching a break. The built-up by the energy input elastic field of tension provides the energy supply for

Fracture formation and fracture propagation. For solid materials there are in particular three different types of material behavior, namely linear-elastic, elastic-plastic and visco-elastic material behavior.

In the linear-elastic material behavior, the applied stress and the resulting strain in the loaded material are proportional to each other and usually have the same course under load and discharge. The proportionality factor is the modulus of elasticity

(Modulus of elasticity). For brittle materials, the modulus of elasticity is large and almost no deformation of the loaded particle occurs until it breaks. The volume-related breaking work is small if the necessary breaking stress is high. The comminution requires a small amount of energy.

In rubber-elastic materials, the modulus of elasticity is small, so that even small stresses cause relatively large deformations. The volume fractional work is large, while the fracture stress is relatively low. The crushing requires a lot of energy. The claimed volumes should therefore be small in order to concentrate the introduced energy locally. For comminution, it is therefore advantageous to use the smallest possible tools.

In the case of elastic-plastic material behavior, irreversible deformation, the so-called plastic flow, occurs in many materials before breakage above a certain limit. Above this yield point, a very small load increase often causes large, not back going deformations. Relief before breakage can result in low elastic recovery. The volumetric fractional work is large while the elastically stored energy is small. The breaking process is neither of a loading speed nor the duration of the

Load dependent, so independent of time. The comminution requires a small amount of energy.

In contrast, in visco-elastic material behavior of the crushing process is time-dependent, the material creeps and relaxed. Examples of visco-elastic substances are thermoplastics. The specific workload to break is great, while the elastic energy stored inside the particles can be converted to heat over time. Very short stress times, in particular below the relaxation time of the material, lead to embrittlement, that is to say lower deformation and correspondingly higher breaking stress and a large elastic energy fraction with smaller specific breaking work. The same effect is achieved by lowering the temperature, which is used for example in the cold crushing of rubber, rubber and similar materials.

Materials with different comminution behavior thus each require specific conditions during comminution. These conditions include in particular the grinding tools used. The term "grinding tool" is understood to mean the grinding vessel with the grinding balls.

In ball mills grinding media made of different materials are used for comminution. Grinders and balls are offered in different materials, so that contamination of the material to be ground by unwanted abrasion of grinding tools can be avoided. In addition, certain materials for the grinding tools are preferably suitable for the comminution of millbase with certain material behavior. In Table 1, some materials are given by way of example with regard to their ability to be used for the comminution of millbase in ball mills.

The overview shown in Table 1 shows that particularly high values for the kinetic energy can be generated, for example, with tungsten carbide tungsten carbide grinding balls due to the very high density. Such grinding tools are therefore preferably suitable for the comminution of abrasive samples with linear-elastic material behavior. However, as a result of the high enumerated milling energy, the regrind can quickly become very hot. Temperature-sensitive regrind must therefore be comminuted at lower speeds or with grinding tools of lower density. The risk of heating is particularly high for regrind with rubber-elastic or visco-elastic material behavior. Depending on the density of the grinding tools used, the critical temperature of the ground material can be reached at different speeds.

Rubber-elastic substances can be comminuted particularly well, for example with grinding tools made of, for example, sintered corundum or zirconium oxide at medium speeds, since an additional frictional stress of the ground material can then be produced by the special surface of these ceramic tools. At high speeds of a ball mill grinding with agate and ceramic grinding tools could even lead to the destruction of the grinding tools themselves. If the grinding jars are used for operation in the ball mill, the grinding tools and their material are sometimes no longer visible to the user. The user of the mill can choose a speed which does not match the grinding tool used, for example by an erroneous input of the speed or because he does not know that the mill should not be operated at certain speeds. As a result, there is the risk that the ball mill is operated at operating parameters for which the grinding tools are not suitable and that damage to the grinding tools occurs.

It follows from this an object of the invention to enable safe operation of the ball mill. In addition, it is an object of the invention to provide a way to avoid operating errors of the ball mill. Another object of the invention is to allow easy operation of the ball mill.

These objects are achieved in a surprisingly simple manner with a ball mill and a method for controlling a ball mill according to the independent claims.

The invention provides a ball mill, in particular a planetary or centrifugal ball mill, on a laboratory scale with a housing, a support device which is rotatably mounted on the housing about a center axis, at least one receiving device for at least one grinding vessel, which is rotatably mounted about a receiving axis to the support device and is carried by the latter about the center axis, a drive for the carrier device, a drive for the receiving device, at least one grinding bowl which can be filled with grinding balls, which comprises a grinding bowl and a lid for releasably closing the grinding bowl, wherein the grinding jar is held in the receiving device when it is inserted into the receiving device, and wherein the grinding jar comprises at least one readable storage means on which at least one information about the grinding jar, in particular about the

Volume and / or the material properties and / or the mass, for example, about the net mass, and / or the maximum speed of the grinding vessel is stored, and the ball mill has a stationary reading device for reading the at least one information from the readable storage means, if Grinder is inserted into the receiving device of the ball mill, and a control device which controls the operation of the ball mill in response to the read information comprises.

The term "maximum speed" is understood to be the highest possible speed at which, if exceeded, the material of the grinding tools, in particular of the grinding bowl, is damaged by excessive input of kinetic energy during operation of the mill.

The control device contributes according to the invention in operation for switching the information read out to the drive of the carrier device and / or the receiving device. The ball mill according to the invention is advantageously formed by the readable storage means, the reading device and the control device, information stored on the storage means about the grinding vessel when setting the operating parameters of a

Ball mill to consider in the grinding process. In particular, the automatic setting of a maximum allowable value for the rotational speed during operation by means of the readable storage means, the reading device, is set by the invention for the grinding vessel used in the respective application and the control device allows. By storing uncritical values for the respective grinding vessel on the readable storage means, the operating parameters of the ball mill can be determined in accordance with the value ranges which are not critical for the respective grinding tool.

The invention thus makes it possible to limit the rotational speed of the ball mill. The operating parameters of the ball mill are advantageously not only with regard to the crushing result to be achieved

Target particle size distribution and the required volume-related energy input into the material to be ground, but also adapted to the grinding tools used. Thus, a possibility is created when setting the

Operating parameters of a ball mill in the milling process to consider which grinding tools are currently being used. In particular, an automatic setting of a maximum allowable value for the rotational speed for the grinding vessel used in the respective application takes place.

In a preferred embodiment of the invention, the ball mill comprises means for wireless data transmission for reading the information. During operation of the ball mill, a connection for transmitting the information which is at least partially wireless is set up between the readable storage means and the reading device. Thus, the ball mill is advantageously constructed in spite of the rotational movements of the readable storage medium carrying grinding vessel to the receiving axis and the center axis simple.

In the context of the invention, it is further provided that the readable storage means comprise a chip and a first Antenna includes. The ball mill includes a second antenna wherein, during operation of the ball mill, radio signals are used between the antennas to transmit information. Thus, the information is transmitted from the readable storage means via a wireless connection between the first and the second antenna via radio.

As a readable storage means in a preferred embodiment, a transponder, that is, a receiving transceiver, which operates according to the query-response system used. An interrogation signal received by the transponder is evaluated according to information of the interrogator. Thereupon, a response signal intended for the interrogator is automatically generated with the desired information, which is evaluated by the interrogator.

In particular, the invention provides for using RFID transponders. RFID (Radio Frequency Identification) advantageously offers the possibility of being able to read and store data contactlessly and without visual contact. The transponder is also referred to as an RFID tag, chip or tag. In addition to the transponder, the RFID method uses a transceiver unit, which is provided by the reading device within the scope of the invention. On the chip of the RFID transponder, data within the scope of the invention at least one information about the grinding vessel, stored. The reading or writing of the information is carried out by radio waves, which can be operated at low frequencies inductively via a near field and at higher frequencies via a remote electromagnetic field.

The distance over which an RFID transponder can be read out varies depending on what is used Frequency band, transmission strength and environmental influences between a few centimeters to a few hundred meters. In the context of the invention, different RFID transponders can be used for the readable storage means. In particular, the invention provides to use a transponder according to the HITAG S standard. However, other transponders are also suitable for the readable storage medium, for example according to HITAG 1, HITAG 2, EM 4x02, EM 4x50 and ISO FDXB transponder.

The reading device used is, for example, the ACG 125 kHz multitag reader module of the company ACG Identification GmbH. In a preferred embodiment of the invention, the reading device comprises a serial interface, for example of the type RS232, via which a connection to other devices, for example to a PC, can be produced.

The readable storage means may be mounted according to the invention on the grinding bowl or on the lid of the grinding vessel. In a particularly simple manner, the ball mill according to the invention can be constructed by the readable storage means is mounted on the lid of the grinding vessel. The data exchange via the second antenna and the reading device is reliably ensured in this arrangement, since in the region of the lid of the grinding vessel substantially no shielding further components of the ball mill are arranged, which could interfere with the connection from the reading device to the readable storage means.

In a preferred embodiment of the invention, it is provided to connect the readable storage means with the outside of the lid via a dielectric material. The dielectric material may in particular comprise an adhesive and has a thickness of at least 2 mm measured perpendicular to the outside of the lid. Such an adhesive layer can perform the function of an electromagnetic insulator and thus enable a particularly reliable reading of the storage means.

This is particularly advantageous if the lid comprises a metallic material, in particular steel.

From a metallic material, such as steel, manufacturing technology in a simple manner required for the interaction with other components of the ball mill outer configurations of the components, such as the lid can be made. In addition, a metallic material with its relatively low brittleness and existing elasticity provides a

Protection against mechanical stress when handling the grinding vessels. Due to the ever increasing demands on the grinding tools, a separation of functions is advantageous, by which for the direct contact of the grinding tool with the material to be ground a material, such as one of those put together in Table 1 is provided for the outer shaping of the above-described mechanical protection for loads in handling, but also a cheaper and easy to edit material, such as metal, is used.

Accordingly, in an advantageous development, the invention provides that the cover is designed in several parts and comprises at least one non-metallic part. For example, the lid may have a socket made of steel, in which a use of the corresponding grinding tool material is attached at a position which points towards the inside of the grinding bowl when the lid is connected to the grinding bowl. Furthermore, the invention provides that the lid with a non-metallic attachment is provided, which serves to receive the readable storage means. The lid comprises in a preferred embodiment of the invention, a holder made of a dielectric material, in particular of plastic, wherein the readable storage means is secured to the holder spaced from the lid.

In addition, such a non-metallic attachment can be designed so that it can be used as a handle for the lid. According to a preferred

According to an embodiment of the invention, the lid comprises a handle which has a dielectric material, in particular a plastic, wherein the readable storage means is attached to the dielectric material of the handle. The handle is formed in an advantageous development as a plastic knob, which is glued and / or screwed to the lid and carries on its upper side the chip or the readable storage means.

In a preferred embodiment of the invention, the readable storage means is attached to a non-metallic part of the lid. For example, the chip may be glued to the outside of the lid, in particular centrally positioned on the lid. In principle, attaching the readable storage means to the cup, for example on the outside is possible.

The housing of the ball mill serves to accommodate at least part of the drive and the grinding tools, as well as installation devices for the grinding tools. The space inside the enclosure is also referred to as the grinding room. In order to be able to read out the information stored on the readable storage means during operation of the ball mill, the reading device uses the second antenna to connect to the readable storage means built up. In a preferred embodiment of the invention, the second antenna is stationary on the ball mill, in particular in the grinding chamber, in a defined distance XAn _te nn _e to the plane in which moves the readable storage means of the grinding vessel or grinding jars during operation of the ball mill attached.

In the context of the invention, the second antenna and / or the reading device with a second antenna can be arranged specifically depending on the design of the ball mill and depending on the application. In addition to the arrangement of the second antenna and / or reading device with the second antenna in the grinding chamber, for example, the reading device can also be mounted outside the grinding chamber in order to save space inside.

In a preferred embodiment of the invention, the reading device is arranged at a predetermined distance from the plane in which the grinding jar or the grinding jars rotate. In particular, under the

Invention provided that the reading device is positioned on the lid of the ball mill. Advantageously, the reading device sits at a distance x _Ante nn _e above the plane of rotation of the readable storage means. In the case of the receivers used for the radio signals, the range is sometimes short, so that the reading device in the lid is advantageously arranged close to the plane in which the readable storage medium rotates.

Depending on which frequency the connection between

Reading device and the storage means is constructed, the distance Xantenne can be selected in a suitable range of values. For the use of frequencies of for example 125 kHz or 134.2 kHz or 13.56 MHz, the invention provides that the distance x _antenna has a value in the range of less than or equal to 60 mm, preferably 30 mm ± 20 mm.

At every grinding, the possibility of operating the ball mill at the user individually desired

To provide operating parameters available, the ball mill comprises an input device in an advantageous development. Via the input device, the user can enter a value for at least one operating parameter, in particular a value for the rotational speed n and / or a value for the maximum speed and / or a value for the grinding time and / or a value for the number and / or duration of grinding pauses and / or a value for the period between two grinding pauses and / or a value for the number of repetitions and / or for carrying out at least one direction of rotation reversal.

By specifying a number of repetitions, the ball mill can be operated such that after passing a refining with set parameters, a new grinding cycle begins, as many times as provided by the number of repetitions. By providing at least one reversal of rotation during a grinding operation, the direction of rotation of the carrier device is changed, which improves the homogeneity of the medium treated in the grinding vessel, in particular during mechanical alloying.

According to the invention, it is provided that the input device comprises means for interval _{specification} , which in operation, in response to the information read out, automatically _predetermine an interval (W _nte n; W _Obe n) for a value W for at least one operating parameter. This will allow the user, at least to select a value W for the operating parameter greater than or equal to W _below and less than or equal to _words . Thus, the invention advantageously provides a possibility by setting an interval for the values set in the operation

Operating parameters at values outside of for reasons of safety or resilience of the materials used from the outset to be able to prevent.

In a preferred embodiment of the invention, the control device conveys the at least one read information to the input device, in particular to the means for interval specification. Thus, the invention advantageously provides a possibility to specify the range of values for operating parameters permissible for the operation, tuned to the properties of the grinding vessel.

In a further embodiment of the invention, the control device regulates or controls the drive of at least the carrier device with the rotational speed n. The term "control device" within the meaning of the invention also includes a device for setting and a device for controlling the drive.

The ball mill advantageously comprises a control circuit for influencing the rotational speed n. The rotational speed is thereby continuously detected by a measuring device. The measured actual values are compared with the specified target value. The control circuit further comprises at least one actuator to act on the speed and to match the setpoint. In the context of the invention, a controller for the speed n can be provided in order to simplify handling by dispensing with the Comparison of the actual values with the setpoint must be made available.

The control device advantageously offers the possibility of ensuring compliance with the desired speed n during operation. The control device mediates the at least one read information to the drive of the ball mill, in particular to the drive of the support device. Thus, the invention advantageously provides the possibility to include in the controlling or adjusting or regulating the drive of at least the carrier device, the at least one information read about properties of the grinding vessel with.

The invention further provides that the ball mill comprises a storage device. The storage device provides at least one storage location for a value for an operating parameter and / or a milling procedure. For example, a grinding operation may provide for grinding at a constant speed over a certain period of time, but a grinding operation may also provide for operation at different speeds over certain time intervals, such as Likewise, within the scope of the invention, grinding processes are provided as a combination of different operating parameters at respectively different values.

In order to provide a value for at least one operating parameter in a memory location, a corresponding value can be stored at any time in advance in a preparatory method step or by the user directly for the upcoming one Grinding process can be entered. The value provided is made available in the memory device for further processing. In particular, a value for an operating parameter may be provided as a milling sequence in response to inputting a value for the at least one operating parameter.

In a preferred development of the invention, the ball mill comprises a transfer device. The relaying device transmits at least one value for an operating parameter from the memory device to the control device. For this purpose, the relaying device is designed such that it can read out values for operating parameters and / or grinding processes from a memory. The at least one read information is then sent to the

Control means in response to the selection of at least one grinding sequence and / or at least one value for at least one operating parameter signals. With the aid of the relaying device, it is thus advantageously possible to make available contents from the memory device for processing in the control device.

The invention also advantageously offers the possibility of producing the grinding vessel with the at least one readable storage means and its

Programming with information about the grinding vessel does not necessarily have to specify the permissible maximum speed n _{max of} a grinding vessel, but depending on the ball mill in each case specifically from grinding vessel-specific information to determine a value for the respective application value for the maximum permissible speed n _ma χ.

Depending on the ball mill are mill-specific information such as the distance of the grinding vessel to Center axis and / or to the receiving axis, which determines a component of the peripheral speed of the grinding vessel, stored in the mill. In a further embodiment of the invention, it is provided that the ball mill, in particular the control device, comprises an evaluation device for forming a value for the permissible maximum speed n _max from the at least one read-out information. The evaluation device uses mill-specific information in order to combine the milling and the grinding vessel specific

Information to determine an operating parameter specification.

In a preferred embodiment of the invention, it is provided that the ball mill, in particular the control device, comprises an interrogation device. The interrogator checks whether the speed n is less than or equal to the maximum permissible speed n _max . With the aid of the interrogator, the ball mill according to the invention can relate the desired speed n by the user to the maximum speed n _max permissible for the respective grinding vessel. As a result, depending on whether the rotational speed n is less than or equal to the permissible maximum rotational speed n _max or greater than the permissible maximum rotational speed n _max , the drive of the carrier device is acted upon. Thus, a drive with at most the maximum speed n _{max is} ensured.

The reading device, the control device, the memory device, the relay device, the input device, the evaluation device and the

In the context of the invention, the interrogation device is connected in each case to at least one of the other devices mentioned, in particular to a connection line which is suitable for the transmission of information. The invention can be used in an advantageous embodiment for a so-called monomillers, as described for example in the patent DE 197 12 905, are used. The description of the Monomühle in the patent DE 197 12 905 is fully incorporated by reference in the present description.

According to the invention, it is provided that the ball mill comprises a mass compensation device, which is provided on the support device, and - as seen from the center of matter - which is arranged opposite at least one receiving device. The mass balancing device forms a moment of inertia relative to the receiving device with the grinding vessel. It has a displaceable balancing mass for changing the counter-moment of inertia, wherein different masses of the receiving device can be compensated with the respectively used grinding vessel by means of the displacement of the balancing mass. The ball mill includes one

Displacement device. With the displacement device, the balancing mass is automatically shifted from the readable storage means in response to the reading of at least one piece of information, in particular the readout of the mass of the grinding bowl. Depending on the mass of the grinding vessel thus can be advantageously made an adjustment of the moment of inertia automatically by moving a balancing mass.

In a further development of the invention, the ball mill comprises at least one balance, which is arranged such that the weight of the filled grinding vessel can be determined in the ready state. This particular weight is then used as information for adjusting the moment of inertia. The invention further relates to a grinding container for a ball mill, as described above, which comprises a grinding bowl and a lid and at least one readable storage means, which is mounted in particular on the grinding bowl or on the lid, wherein on the readable storage means at least one milling vessel-specific information, in particular via the volume and / or the material properties and / or the mass, in particular on the net mass, and / or on the maximum speed of the grinding vessel can be stored. With the grinding vessel according to the invention in particular existing ball mills can be retrofitted, in which a reading device and a second antenna are provided and the information read in the control or adjustment or regulation of the drive of the ball mill are taken into account.

The invention further provides a method of controlling a ball mill with a grinding jar as described above, comprising the steps of: a) inputting a speed n by the user; b) reading at least one piece of information from the readable storage means of each grinding jar a reading device, c) automatically forming a value for the permissible maximum speed n _max from the at least one read information, d) automatically checking whether the speed n is less than or equal to the permissible maximum speed n _max , and e) if the speed n is less than or equal to n equal to the permissible maximum speed n _max is: driving the ball mill at the speed n. According to the invention, at least one grinding process can be stored in the storage device in a preparatory method step. This preparatory process step is multi-process, that is, it can indeed, but does not have to be performed before each grinding. For example, when commissioning the mill for its intended use, the user may save specific milling operations so as not to have to re-enter them each time they are ground.

A milling process is represented by a data record which comprises at least one value for at least one operating parameter. The memory device is thus advantageously programmable according to the invention individually for the typical applications of the user.

In an advantageous development of the invention, at least one further value for at least one operating parameter and / or at least one milling procedure is specified in step a), and in step b) at least one piece of information from the readable storage means of each grinding vessel and the at least one in step a) predetermined value and / or the at least one predetermined in step a) grinding process read out of the memory device. The method according to the invention therefore makes it possible to use parameters which are provided on the readable storage means of the grinding vessel as well as values predefined by the user and in particular stored in the storage device for the operation of the ball mill, depending on the application.

If the speed n predetermined in step a) is greater than the permissible maximum speed n _max , then, according to FIG Invention advantageously reduces the speed n at least to the value n _max . Reducing a speed to at least the value n _max is carried out according to the invention preferably automatically on the result of the query whether the predetermined speed n is less than or equal to the maximum permissible speed, if this negative, the predetermined speed n is greater than the permissible Maximum speed is.

In order to be able to adapt the method according to the invention to different applications and to be able to use the ball mill variably in a very wide range of applications, it is provided in an advantageous development of the method according to the invention that in step c) a value for the permissible maximum grinding time t _Ma hi_maχ and / or a value for the required number n _break of Mahlpausen and / or at least one value for the duration of at least one Mahlpause t _break, and / or at least one value the distance Δtp _housing between two breaks, and / or at least one value for the number N of repetitions and / or at least one information about the execution of a reversal of rotation is formed.

In a further advantageous embodiment of the invention, the rotational speed n _max and / or the permissible maximum grinding time t _Mahl _ _max and / or the required number n _break of Mahlpausen and / or the duration of at least one Mahlpause t _break and / or the distance .DELTA.p _break between two pauses and / or the number N of repetitions and / or the information about the execution of a reversal of rotation including user-defined parameters, in particular the number and / or size and / or material of the grinding balls and / or material properties of the material to be ground formed. Within the scope of the invention, in particular based on the information read out or including user-defined parameters, a value for the permissible maximum speed v _{max of} the

Grinding vessel, that is, the speed at which the grinding vessel would be damaged by an excessive energy input, are formed.

If a ball mill with a mass balancing device, which has a displaceable balancing mass, and with a displacement device for automatically moving the balancing mass is provided in the context of the method according to the invention, the position of the balancing mass in response to the reading at least one piece of information, in particular to the reading Adjust the mass of the grinding vessel from the readable storage medium.

In the context of the method according to the invention, the

Readout of the information from the readable storage means or the description of the storage means with the information to be read in the operation of the ball mill depending on the type of the chip and the first antenna used at all known frequencies. In particular, in an exemplary embodiment of the invention, it is provided that the reading device reads out at least one piece of information from the readable storage means of each grinding vessel at a frequency of 125 kHz and / or 134.2 kHz and / or 13.56 MHz.

The invention also provides for the use of an RFID transponder in a method for controlling a ball mill, as described above, wherein on a transponder at least one piece of information about a Grinding vessel, in particular on the volume and / or the material properties and / or the mass and / or the maximum speed of the grinding vessel is stored and an antenna and a reading device are provided to correspond with the transponder, so that the at least one on the transponder stored information is available for a control of the ball mill.

The invention will be described in more detail below with reference to embodiments with reference to the accompanying figures. The same components are identified on all figures with the same reference numerals.

Show it:

Table I Overview of materials for grinding tools in ball mills,

Figure 1 is a schematic representation of the ball mill according to the invention according to a first

Embodiment of the invention,

FIG. 2A shows a schematic representation of the ball mill according to the invention with coding and decoding devices for two receiving devices in a first position,

FIG. 2B shows a schematic representation of the view of the decoding device 210,

Figure 2C is a schematic representation of the ball mill according to the invention with coding and decoding devices for two

Receiving devices in a second position, which compared to the first position by a half revolution of the carrier device is shifted,

FIG. 3 shows a schematic representation of the ball mill according to the invention in accordance with a second embodiment of the invention,

4 shows a schematic representation of the ball mill according to the invention according to a third embodiment of the invention,

Figure 5 is a schematic representation of the ball mill according to the invention according to a fourth

Embodiment of the invention,

FIG. 6 shows a schematic representation of the ball mill according to the invention in accordance with a fifth illustration of the invention,

Figure 7 is a schematic representation of a first

Embodiment of the grinding vessel according to the invention,

Figure 8 is a schematic representation of a second

Embodiment of the grinding vessel according to the invention.

FIG. 1 shows a grinding vessel 5, which is located in a receiving device of a ball mill, so that it drives the carrier device or, as shown in FIG. 1, a drive 27 for the receiving device in rotation about the receiving axis and about the center axis the ball mill can be moved.

The grinding vessel 5 is provided with a readable storage means

100 provided. The readable storage means 100 has a Chip 110 and a first antenna 111. On the chip 110, a value n _max for the maximum allowable speed for the grinding vessel 5 is stored.

The ball mill further comprises a stationary second antenna 121. To read the information about the maximum permissible speed n _max , data signals are exchanged via the antennas 111 and 121 in order to make the information n _max accessible from the chip 110. A reading device 120 accesses the information n _ma χ via the second antenna 121. In operation, a wireless connection 112 is established between the first antenna 111 and the second antenna 121. The remaining connections represented by knuckles in the figures may be wireless or wired connections. The reading device 120 forwards the information n _max to the control device 150 which transmits the information for display in the display 123.

In operation, at the start of the ball mill, a first revolution of the carrier device about the center axis is performed at a low speed compared to the operating speed. In this initialization run, each grinding jar is identified by means of the readable storage means. If the ball mill comprises, for example, two grinding vessels, both grinding vessels are identified in the initialization cycle via the reading device.

Furthermore, it is ensured that in the processing of the read-out information is taken into account in which

Receiving device is the respective grinding vessel. For this purpose, co-rotating coding means for the respective recording device and a fixed decoding device are provided with the carrier device 1. With the Decoding means, the coding means are detected and the information contained is read out.

FIGS. 2A to 2C show a corresponding embodiment with two receiving devices. The ball mill has a carrier device 1. In operation, with the carrier device 1, a first and a second receiving device 201, 202 rotate about the center axis 15. On the carrier device 1 are adjacent to the first receiving device 201 first

Coding 211 attached. Adjacent to the second receiving device 202, second coding means 212 are attached to the carrier device 1.

The first and second coding means 211, 212 are in this example designed as a magnet arrangement with a plurality of magnets, which are arranged in particular at different radii. In the embodiment shown, two magnets are provided for each.

The ball mill comprises a detection and decoding device 210, which cooperates with the control device 150. FIGS. 2A and 2C show the connection between the decoding device 210 and the control device 150. For the sake of clarity, the connections between the further devices and the control device 150 are not shown in these figures.

The decoding device 210 is stationary in the ball mill, in particular in the grinding chamber, for example under the carrier disk. The decoding device 210 has decoding means 220. The decoding means 220 are in particular designed as a Hall sensor arrangement, which corresponds to the magnet arrangement. FIG. 2B shows a view of the decoding device 210. In the embodiment shown, three Hall sensors are provided, which are arranged on different radii corresponding to the magnets.

In the position of the carrier device 1 according to the illustration in FIG. 2A, the magnets are respectively detected by means of the associated Hall sensor. The first receiving device 201 is recognized from the signals of the corresponding Hall sensors.

In the position of the carrier device 1 as shown in FIG. 2C, signals of the magnets of the second coding means 212 are received by means of the Hall sensors. From the signals of the corresponding Hall sensors, the second recording device 202 is detected. For this purpose, the signals of the Hall sensors are read out by the control device and processed. In combination with the detection of grinding jars stands in the

Operation of the ball mill also the information available about which recording device is equipped with which grinding vessel. Each grinding vessel is thus assigned a unique position in the mill. This position is available for further processing regardless of where in the grinding chamber, the antenna is arranged.

In particular, according to the first embodiment of the invention shown in FIG. 1, the ball mill additionally comprises an input device 122, by means of which a user can input a value n for the rotational speed of the grinding vessel. The input device 122 is also connected to the display 123, so that in the display the user-specified speed n and read from the chip 110 of the readable storage means 100, maximum permissible speed n _max are displayed. The input device 122 is furthermore connected to the control device 150. In one embodiment of the invention, the input device 122 and the display 123 are preferably designed as a touch-screen display.

The control device 150 comprises an interrogator 155, in which it is checked whether the rotational speed n is less than or equal to the permissible maximum rotational speed n _max . If this is the case, the control device 150 causes the driving of the grinding vessel, shown here on the basis of the drive 27 for the receiving device of the grinding vessel 5 with the speed n, which is smaller or at most equal to the maximum permissible speed n _max .

If the query that the rotational speed n is greater than n _ma χ, the controller 150 causes in one of several möglchen embodiments of the invention, the driving of the grinding vessel with the maximum allowable speed n _max .

According to the second embodiment of the invention shown schematically in Figure 3 may be stored on the chip 110 of the readable storage medium 100, a different information I than the maximum permissible speed n _max for the grinding vessel 5. The information I is from the

Chip 110 via the first antenna 111 and the second antenna 121 by means of the reading device 120 of an evaluation device 152 in the control device 150 supplied. The evaluation device 152 determines, based on the information I, a value for the maximum permissible speed n _max . In the display 123 can be displayed in the context of the second embodiment of the invention, the information I as determined therefrom, allowable maximum speed in addition to the predetermined by the user by means of the input device 122 speed n. The Control device 150 with the interrogator 155 is just as in the first embodiment described above with the drive 27 in connection.

In the third embodiment of the invention shown in FIG. 4, the control device 150 transmits the read-out value for the permissible maximum speed n _max to the input device 122, which then inputs a value n for the rotational speed which is less than or at most equal to the permissible maximum rotational speed n _max must be allowed. The control device 150 transmits the read value n _max to the display 123, in which the speed n input via the input device is also displayed. The input device 122 sets the value n, which, due to the limitation provided in the third embodiment, is already safely smaller or at most equal to the permissible maximum speed n _max to the control device 150 which is connected to the drive 27 with the aid of which the grinding vessel 5 at a speed n which is less than or equal to the maximum permissible speed n _{max is} rotated.

A refinement according to the second embodiment corresponding to the embodiment of the third embodiment of the invention is shown schematically in Figure 5 as a fourth embodiment of the invention. By way of the readable storage means 100, information I is transferred by means of the first antenna 111 and the second antenna 121 via the reading device 120 to the control device 150, which has an evaluation device 152. In the evaluation device 152, a value for the permissible maximum speed n _{max is} determined from the information I. In response to determining the maximum permissible speed n _max is in the input device 122 allows n a value for the speed entering which the value of the maximum permissible speed n _max must not exceed. The value n and the maximum permissible rotational speed n _max and, for example, also the information I are displayed to the user with the aid of the display 123. From the input device 122, the value n is transferred to the control device 150, which drives the grinding vessel 5 by acting on the drive 27 of the

Receiving device at the speed n, which does not exceed the maximum permissible speed n _max , causes.

A further embodiment of the invention is shown schematically in FIG. 6, in which, apart from information provided on the chip 110 of the readable storage means 100, further information I ₂ that can be provided in a storage device 130 can be used to operate the ball mill. The evaluation device 152 receives the information Ii which is stored on the chip 110 of the readable storage means 100 in accordance with the procedure described above. Further information I ₂ is available in the memory device 130. The storage device 130 is in communication with a relay device 135. The

Input device 122, which allows the user to input a value for speed n, is also in communication with relay device 135.

In response to the inputting of a value for the rotational speed n, the relaying device 135 forwards the information I ₂ from the memory device 130 to the control device 150, in particular to the evaluation device 152. In the evaluation device 152, a value for the maximum permissible rotational speed n _{max is} formed from the information Ii and the information I ₂ .

This and values for the information Ii and I ₂ as well as the user-selected speed n can be displayed on the display 123. From the input device 122, the control device 150, in particular the interrogator 155 receives the value for the selected speed n. The interrogator 155 receives from the control device 150 the value for the maximum permissible speed n _max . The

Control device 150 is connected to the drive 27 in such a way that a driving of the grinding vessel 5 at a speed n, which does not exceed the maximum permissible speed n _max , is caused.

FIG. 7 shows a cross section of a first embodiment of the grinding vessel 5 according to the invention. The grinding vessel 5 comprises a grinding bowl 51 and a lid 52 which closes the grinding bowl. The grinding bowl 51 has a socket 530, which may be made of metal, for example, and an insert 535, which is made of the grinding tool material. The lid 52 includes a socket 523, which may be made of metal, for example, and an insert 525 of the grinding tool material. When the lid 52 is placed on the grinding bowl 51, a grinding bowl interior is formed which is enclosed by grinding tool material of the insert 525 of the lid and the insert 535 of the bowl.

The lid 52 has the first shown in FIG

Embodiment on a recess in which a readable storage means 100 is arranged. The readable storage means 100 is connected via an adhesive layer 160 to the lid 52. By appropriate choice of the thickness of the adhesive layer 160 is ensured that the metallic material of the lid 52 does not interfere with data transmission from or to the readable storage means 100.

FIG. 8 shows a cross section of a second embodiment of the grinding vessel 5 according to the invention. The lid 52 has a spacer in the form of a handle made of plastic 160. At the top of the handle, a readable storage means 100 is arranged. The readable storage means comprises the chip 110 and the first antenna 111. The distance of the readable storage means 100 to the socket 523 cover 52 is 30 mm, so that the metallic material of the cover 52 does not interfere with a data transfer from or to the readable storage means 100. The handle made of plastic

160 is bolted to the lid 52. In addition, the handle can be glued to the lid 52.

Common to all embodiments is that each grinding vessel 5 receives a readable storage means 100, in particular a transponder, which can be programmed unmistakably and logs the grinding vessel 5, for example as a 250 ml agate vessel or 500 ml zirconia vessel in the system, thus in particular the device control.

The reading device 120, also referred to as reader, identifies the grinding vessel 5 introduced into the receiving area within the grinding chamber. The device control is therefore always aware of which grinding vessel is being used in the ball mill. The device control adjusts a pre-set or freely programmable parameter set to optimally match the performance of the ball mill to the grinding tool. Each preset setting can be freely parameterized and can be reset to the factory setting as the default setting. In an application with agate grinding cups, the invention enables, for example, that the ball mill according to the invention recognizes the agate grinding vessels and automatically specifies a maximum speed which is harmless for agate milling tools. Another application example is that the user wants to grind with agate grinding cups, but wants to use relatively small grinding balls. Therefore, a larger maximum speed than the preset one may be allowed. In the context of the invention, it is therefore possible to parameterize a maximum permissible speed. For example, a so-called administrator mode can be provided for this purpose.

Another application example is the milling of a temperature-sensitive material in a cemented carbide tungsten carbide grinding vessel. In Administrator mode, the parameter setting can be set to allow a maximum grinding time and a maximum speed after the carbide tungsten carbide grinding vessel has been detected.

Another example of the application of the invention is a long-term milling with zirconia grinding vessels. The ball mill according to the invention recognizes the zirconium oxide

Grinders and specifies a maximum grinding time and at least to be paused grinding breaks.

Another application for the invention is the specification of various applications. The user is provided with grinding vessels made of various materials. For example, it may be intended to use agate grinding jars only for homogenization. For this, the parameterization, in particular in the administrator mode, can be set so that, after the detection of the agate Grilling vessel is allowed a low maximum speed.

With the automatic recognition of the grinding jars used in each specific application, certain

Limits of the grinding parameters are fixed preset so that incorrect operation can be advantageously avoided.

It will be apparent to those skilled in the art that the invention is not limited to the embodiments described above, but rather can be varied in many ways.

LIST OF REFERENCE NUMBERS

1 carrier device

15 center axis

201, 202 first, second receiving device

211, 212 first, second coding means for the first, second receiving device

210 decoding device

220 decoding means; Hall sensors

27 Drive for recording device

5 grinding vessel

51 grinding bowls

52 lids

523 Version of the lid

525 Use of the lid

530 version

535 use

100 readable storage media

110 chip

111 first antenna

112 wireless connection

120 reading device

121 second antenna

122 input device

123 display

130 storage device

135 relay device

150 control device

152 evaluation device

155 Interrogator

160 dielectric material, adhesive, plastic

Claims

claims

1. ball mill, in particular planetary or

Centrifugal ball mill on a laboratory scale, with a housing, a support device which is rotatably mounted on the housing about a center axis, at least one receiving device for at least one grinding vessel (5) which is rotatably mounted about a receiving axis to the support device and is carried by this about the center axis, a drive for the carrier device, a drive (27) for the receiving device, at least one grinding bowl (5) which can be filled with grinding balls, which comprises a grinding bowl and a lid for releasably closing the grinding bowl, the grinding bowl being held in the receiving device, if it is in the receiving device is used, characterized in that the grinding vessel (5) comprises at least one readable storage means (100) on which at least one grinding vessel specific information, in particular about the volume and / or the material properties and / or the mass and / or on the

Maximum speed of the grinding vessel, storable, and the ball mill, a reading device (120) for reading the at least one piece of information from the readable storage means (100) when the grinding vessel in the

Receptacle of the ball mill is inserted, and a control device (150), which controls the operation of the ball mill in response to the read information comprises.

2. Ball mill according to claim 1, characterized in that the ball mill comprises means (111, 121) for wireless data transmission for reading the information.

3. Ball mill according to one of the preceding claims, characterized in that the readable storage means (100) comprises a chip (110) and a first antenna (111) and that the ball mill comprises a second antenna (121), wherein in operation the ball mill between the Antennas (111, 121) Radio signals are exchanged to transmit information.

4. Ball mill according to one of the preceding claims, characterized in that the readable storage means (100) on the lid (52) of the grinding vessel (5) is mounted.

5. Ball mill according to one of the preceding claims, characterized in that the readable storage means (100) with the outside of the lid (52) via a dielectric material (160), which in particular comprises an adhesive, is connected to a thickness of at least 2 mm ,

6. Ball mill according to one of the preceding claims, characterized in that the cover (52) has a holder made of a dielectric material (160), and the readable storage means (100) is secured to the holder spaced from the lid.

7. ball mill according to one of the preceding claims, characterized in that the second antenna (121) fixed to the ball mill at a defined distance Xan _t enne to the plane in which during operation of the ball mill, the readable memory means (100) of the grinding vessel ( 5) moves, is attached.

8. Ball mill according to claim 7, characterized in that the distance X _{antenna is} less than or equal to 60 mm.

9. Ball mill according to one of the preceding claims, characterized in that the ball mill comprises an input device (122) for inputting a value for at least one operating parameter, in particular for inputting a value for the rotational speed n and / or a value for the maximum speed and / or a value for the grinding time and / or a value for the number and / or duration of grinding pauses and / or a value for the period between two grinding pauses and / or a value for the number of repetitions and / or for performing at least one reversal of direction.

10. Ball mill according to one of the preceding claims, characterized in that the input device (122) comprises means for

Interval specification includes, which automatically specify an interval (W _down , W _above ) for a value W for at least one operating parameter in response to the read information.

11. Ball mill according to one of the preceding claims, characterized in that the control device (150) for switching the at least one read information to the

Input device (122), in particular to the means for Intervallvorgabe is formed.

12. Ball mill according to one of the preceding claims, characterized in that the control device (150) is designed for controlling the drive of at least the carrier device with the rotational speed n.

13. Ball mill according to one of the preceding claims, characterized in that the ball mill comprises a memory device (130) with at least one memory location on which a value for an operating parameter and / or a milling process is stored.

14. Ball mill according to one of the preceding claims, characterized in that the ball mill a relay device (135) for passing at least one value for a

Operating parameter from the memory device (130) to the control device (150), wherein the relay device (135) for reading out values for operating parameters and / or reading a Mahlablaufes from a memory and for signaling the at least one read information to the control device (150 ) is designed in response to the selection of at least one grinding sequence and / or at least one value for at least one operating parameter.

15. Ball mill according to one of the preceding claims, characterized in that the ball mill comprises an evaluation device (152) for forming a value for the maximum permissible speed n _max from the at least one read information.

16. Ball mill according to one of the preceding claims, characterized in that the ball mill comprises a mass balancing device which is provided on the support device and is arranged with respect to the center axis of the at least one receiving device to a moment of inertia relative to

Recording device to form the grinding vessel, and which has a displaceable balancing mass for changing the moment of inertia, wherein the different masses of the grinding vessel are compensated by means of the displacement of the balancing mass, and wherein the ball mill a displacement device for automatically moving the balancing mass in response to the readout of the information , in particular to the reading of the mass of the

Grinding jar, from the readable storage means (100).

17. Milling vessel (5) for a ball mill according to one of the preceding claims, characterized in that the grinding vessel (5) comprises a grinding bowl (51) and a lid (52) and at least one readable storage means (100) which in particular on the grinding bowl ( 51) or on the lid (52) is mounted, wherein on the readable storage means (100) at least one grinding vessel specific information, in particular on the volume and / or the material properties and / or the mass and / or the maximum speed of the grinding vessel (5), can be stored.

18. A method for controlling a ball mill with at least one grinding vessel (5) according to claim 1 comprising the following steps: a) inputting a speed n by the user, b) reading at least one piece of information from the readable storage means (100) of each grinding vessel by a Reading device (120), c) automatically forming a value for the permissible maximum speed n _max from the at least one read information, d) automatically checking whether the speed n is less than or equal to the permissible maximum speed n _max , and e) if the speed n is less than or equal to the maximum permissible speed n _max : driving the ball mill at speed n.

19. The method according to claim 18, characterized in that at least one grinding process in the

Memory device (130) is stored, which comprises at least one value for at least one operating parameter.

20. The method according to any one of the preceding claims, characterized in that in step a), a further value for at least one operating parameter and / or at least one milling procedure is specified, and in step b) at least one piece of information from the readable memory means (100) of each

Grinding vessel (5) and the at least one in step a) predetermined value and / or the at least one predetermined in step a) grinding process from the memory device (130) are read out.

21. The method according to any one of the preceding claims, characterized in that the speed n is reduced at least to the value n _max , if the predetermined speed in step a) n is greater than the maximum permissible speed n _max .

22. The method according to any one of the preceding claims, characterized in that in step c) also a value for the maximum permissible grinding time t _Ma hi_maχ and / or a value for the number n _break of Mahlpausen and / or a value for the duration of at least one Mahlpause tp _auS e and / or a value of the distance .DELTA.t _break between two pauses and / or a value for the number N of repetitions and / or information on the implementation of a

Direction of rotation reversal is formed.

23. The method according to any one of the preceding claims, characterized in that the speed n _max and / or the permissible maximum grinding time t _Mah i_m _a χ and / or the number n _break of meal breaks and / or the duration of at least one Mahlpause t _PauS e and / or the distance .DELTA.t _PaU se between two pauses and / or the number N of repetitions and / or the information about the execution of a reversal of rotation with the inclusion of user-defined parameters, in particular the number and / or size and / or material of the grinding balls and / or material properties of the ground material is formed.

24. A method for controlling a ball mill according to claim 16 according to one of the preceding claims, characterized in that in response to the reading at least one information, in particular on the reading of the mass of the grinding vessel (5) from the readable storage means (100) the position the balancing mass is adjusted.

25. The method according to any one of the preceding claims, characterized in that by the reading device (120) at least one piece of information from the readable storage means (100) of each

Mahlgefäßes (5) at a frequency of 125 kHz and / or 134.2 kHz and / or at 13.56 MHz is read.