Laboratory mill and calibration standard for a laboratory mill

Abstract

The invention relates to a laboratory mill (1), in particular a laboratory-scale vibrational and / or ball mill, such as a centrifugal force ball mill and / or planetary ball mill, comprising at least one grinding beaker holder (6) for at least one grinding beaker (5) and comprising at least one calibration sensor unit (7) with at least one calibration sensor (8). According to the invention, the calibration sensor (8) is arranged spatially adjacently to the grinding beaker holder (6) during a grinding operation, and the calibration sensor (8) detects at least one movement characteristic during the grinding operation.

Description

[0001] Laboratory mill and calibration standard for a laboratory mill

[0002] The invention relates to a laboratory mill, in particular a vibrating mill and / or ball mill, such as a centrifugal ball mill and / or planetary ball mill, on a laboratory scale, wherein the laboratory mill has at least one grinding bowl holder for at least one grinding bowl.

[0003] Furthermore, the present invention relates to a calibration standard for a laboratory mill of the aforementioned type.

[0004] Furthermore, the present invention relates to a method for calibrating a laboratory mill and a measuring and calibration system.

[0005] Grinding bowls of conventional vibratory mills perform circular oscillations in a horizontal plane. Due to the inertia of the balls, they impact the sample material on the rounded end surfaces of the grinding bowls with high energy, thereby comminuting it. Due to the movement of the bowl and the movement of the balls, intensive mixing occurs simultaneously. Using smaller balls, the degree of mixing can be further increased. Using many small balls, such as glass beads, even biological cells can be disrupted. The strong frictional impact between the balls ensures effective cell disruption.

[0006] In centrifugal ball mills, grinding bowls are arranged eccentrically to a drive axis and move in a circular path. To prevent a grinding bowl from rotating around its own axis, a sprocket, gear, toothed belt, rod guide, Schmidt coupling, or a similar device can be used to prevent absolute rotation of the grinding bowl.

[0007] Planetary ball mills generate a combined orbital and rotary motion of the grinding bowls. The rotation of the grinding bowls creates radially outward-directed centrifugal forces on the material being ground. In contrast to centrifugal ball mills, the drive of the grinding bowls in a planetary ball mill is designed to cause an absolute rotational movement of the grinding bowls around their own axis, the planetary axis. This means that significantly larger centrifugal force components are generated in a planetary ball mill than in a centrifugal ball mill. This centrifugal force component is superimposed on the centrifugal force component generated by the rotation of the grinding bowls around the central axis. Centrifugal forces and the Coriolis force result in a resulting force field to which the grinding ball and the material being ground are exposed.

[0008] The kinematic coupling of mechanical components of the laboratory mill with a mill drive, which depends on the mill type, determines a specific movement regime or movement behavior of the grinding bowl during grinding operation.

[0009] A vibrating mill, for example, can have a pendulum drive for grinding jars that perform circular oscillations in a horizontal position. The pendulum drive can be designed in several parts with an eccentric shaft that is rotatably mounted about a vertical eccentric axis, and each rocker is mounted so that it can oscillate about a vertical oscillation axis and is connected to the eccentric shaft via couplers. Grinding jar holders for the grinding jars can be attached to the rocker arms. For torque transmission, a motor unit can be coupled to the eccentric shaft via a V-belt. The eccentric shaft itself can be rotatably mounted on a base plate of the mill. The kinematic coupling of the mechanical components of the vibrating mill with the motor unit means that the grinding jars perform circular oscillations when the mill is in operation. The movement regime orThe movement behavior of the grinding bowl during grinding operation can be characterized in particular by the oscillation frequency.

[0010] Planetary or centrifugal ball mills can have a support device rotatably mounted about a central axis, as well as a grinding bowl holder for at least one grinding bowl, which is rotatably mounted about a receiving axis relative to the support device and is guided by the support device about the central axis. The ball mill can have a drive for the support device, wherein a motor comprises a V-belt drive coupled to the support device. Furthermore, a drive for the grinding bowl holder can be provided, which is designed to set the grinding bowl holder in rotation about a planetary axis. With the support device around the central axis, the rotation of the support device is transmitted to the grinding bowl holder.The movement regime of the grinding bowl is characterized by a combined orbital and rotary motion of the grinding bowl, whereby the rotation of the grinding bowl exerts a radially outward centrifugal force on the material to be ground. The drive of the grinding bowl in the planetary ball mill causes an absolute rotational movement of the grinding bowl around its own axis, the planetary axis, so that in a planetary ball mill, a significantly larger, wider centrifugal force component is generated compared to a centrifugal ball mill. This centrifugal force component is superimposed on the centrifugal force component generated by the rotation of the grinding bowl around the central axis.

[0011] In connection with the control and / or regulation of the movement regime or the movement of the grinding jar during grinding operation, the input variable of the control and / or regulation can be at least one desired movement parameter of the grinding jar during grinding operation, specified by a mill operator and / or reported back by a sensor of the control and / or regulation device. For example, the input variable can be the vibration frequency of the grinding jar or the rotational speed of the grinding jar.If, particularly due to inaccurate kinematic coupling of the mechanical components of the laboratory mill with a drive, or furthermore particularly due to technical defects, there is a deviation of an actual movement parameter of the grinding jar during grinding operation from a specified and / or reported target movement parameter, this can lead to the actual grinding result deviating from the expected grinding result and reproducibility of the grinding result cannot be guaranteed. If the deviations remain undetected, conclusions about the causes of systematic actual-target value deviations of the movement parameter are not possible and technical defects remain undetected. Grinding results and / or grinding material properties can be misinterpreted, which can lead to disruptions in subsequent processes and can impair conclusions about the physical and chemical properties of the grinding material from the achieved grinding results.

[0012] It is therefore necessary to calibrate the laboratory mill to ensure that the actual movement parameters of the grinding bowl during grinding operation deviate only slightly from the specified and / or reported target movement parameters.

[0013] The object of the present invention is to provide a laboratory mill, in particular a vibrating mill and / or ball mill, such as a centrifugal ball mill and / or planetary ball mill, on a laboratory scale of the type mentioned above, and a method for calibrating such a laboratory mill. This method allows, in a simple manner and at the location of the laboratory mill, an exact determination of actual-to-setpoint deviations of at least one movement parameter characterizing the grinding process during grinding operation and can thus contribute to identifying any existing technical defects, in particular an inexact kinematic coupling of the mechanical components of the laboratory mill to a drive. In particular, a high reproducibility of grinding results should be ensured in a simple manner and a misinterpretation of grinding results resulting from setpoint-to-actual value deviations of the movement parameter should be avoided.

[0014] The aforementioned objects are equally achieved by a laboratory mill having the features of claim 1, a calibration standard for a laboratory mill having the features of claim 7, a method for calibrating a laboratory mill having the features of claim 10, and a measuring and calibration system having the features of claim 11. Advantageous embodiments of the invention are the subject of the subclaims.

[0015] The laboratory mill according to the invention has at least one grinding bowl holder for at least one grinding bowl and at least one calibration sensor unit with at least one calibration sensor, wherein the calibration sensor is arranged spatially adjacent to the grinding bowl holder during the grinding operation and wherein the calibration sensor detects at least one movement characteristic during the grinding operation.

[0016] The laboratory mill according to the invention can further comprise a control and / or regulating device for controlling and / or regulating the movement regime or movement of the grinding bowl during the mill's grinding operation. A sensor of the control and / or regulating device can preferably be arranged at a greater distance from the grinding bowl holder and / or the grinding bowl than the calibration sensor, in particular adjacent to a drive of the grinding bowl holder.

[0017] According to the invention, the movement parameter is a movement parameter of the movement of the calibration sensor that is suitable for characterizing a grinding process with regard to the grinding result, in particular an acceleration and / or a rotational speed to which the calibration sensor is subjected during grinding operation. The calibration sensor unit can comprise all motion sensors that appear appropriate to a person skilled in the art and that detect movement and / or acceleration. Advantageously, the calibration sensor is an acceleration sensor and / or an optical sensor and / or a mechanical sensor. The acceleration sensor can, for example, be formed by a MEMS sensor (micro-electro-mechanical sensor), which outputs an acceleration in voltage values ​​and makes it detectable for data processing.The optical sensor can function essentially analogously to, for example, an optical computer mouse. The mechanical sensor can be a vibration and / or inclination sensor. The movement characteristic can be a voltage characteristic and / or an optical characteristic and / or an inclination angle characteristic and / or other movement characteristics that a person skilled in the art considers appropriate.

[0018] The result of a "calibration" within the meaning of the invention is then the determination of an actual-setpoint deviation of the motion parameter detected by the calibration sensor or of another motion parameter determined therefrom from a predetermined setpoint of the motion parameter and / or a setpoint reported back by a sensor of a control and / or regulating device of the laboratory mill. For example, the acceleration of the calibration sensor can be recorded over a specific period of time as a motion parameter in order to determine the oscillation frequency at which the calibration sensor is moved together with the grinding bowl holder during the grinding process from a temporal progression of the acceleration as a further motion parameter. The result of the calibration can then be a determination of the actual-setpoint deviation of the oscillation frequency.

[0019] During grinding operation, the calibration sensor can generally be attached or held directly to the grinding bowl holder and / or to the grinding bowl itself. However, it is advantageous if it is held and / or attached to and / or in a calibration standard attached to the grinding bowl holder.

[0020] The calibration sensor moves along the grinding bowl holder during grinding operation. By arranging the calibration sensor in the area of ​​the grinding bowl holder and / or in the holding area of ​​a grinding bowl of the laboratory mill, any influences on the kinematic coupling of mechanical components of the laboratory mill with a mill drive that could lead to actual-setpoint deviations of the movement parameter can be recorded with high accuracy. An evaluation unit is provided for evaluating and / or logging the movement parameter recorded by the calibration sensor unit, in particular for determining a temporal profile of the movement parameter. In vibratory mills, a single- or multi-axis profile of the acceleration of the calibration sensor can advantageously be provided over a phase of the grinding operation of a predetermined duration.

[0021] In particular, the evaluation unit is designed to determine a target-actual value deviation of the motion characteristic measured during grinding operation and / or a further motion characteristic derived therefrom from a predetermined target motion characteristic and / or a target motion characteristic reported back by a sensor of a control and / or regulating device of the laboratory mill. For example, the input variable for the control and / or regulating device of a vibratory mill can be an oscillation frequency of the grinding bowl holder.

[0022] The setpoint-actual value deviation then represents the result of the calibration of the laboratory mill and can be displayed and / or saved in the form of a calibration report.

[0023] The method according to the invention accordingly provides that at least one actual movement characteristic is recorded during the grinding operation using at least one calibration sensor arranged spatially adjacent to the grinding bowl holder and / or at the location of the grinding bowl holder during the grinding operation, and that for calibration purposes a setpoint-actual value deviation of the recorded actual movement characteristic and / or a further actual movement characteristic derived therefrom from a predetermined setpoint movement characteristic and / or a setpoint movement characteristic reported back by a sensor of a control and / or regulating device of the laboratory mill is automatically determined.

[0024] The measured value can be calibrated by determining the movement behavior of the calibration sensor during grinding operation. In a vibratory mill, for example, the acceleration measured with the calibration sensor can be recorded during the movement of the grinding bowl holder. The sensor's acceleration is at its highest at the reversal points of its movement. The acceleration behaves sinusoidally. During the start-up phase of the vibratory mill, the frequency of the movement increases and becomes irregular. Once a maximum frequency is reached, the period remains essentially constant. At this point in time, the period of the oscillating movement can be calculated based on the zero crossings (acceleration = zero). The time interval between two zero crossings corresponds to half the period. This can be used to determine the total period.The frequency can be determined from the period duration and thus also the deviation of the actual frequency from the specified or reported target frequency as a result of the calibration.

[0025] The deviation between the setpoint and actual values ​​is preferably determined in a process phase of the grinding operation after a run-up and / or settling phase of the grinding operation. In the process phase in which the determination of the actual values ​​is provided as the basis for calibration, the movement regime of the grinding jar holder or the calibration sensor is characterized by essentially constant movement parameters and / or by reaching a predetermined level of at least one movement parameter. In particular, a maximum oscillation frequency and / or an essentially constant period duration or a predetermined target speed can be reached in the process phase.

[0026] Further preferably, on the basis of the determined setpoint-actual value deviation, an adjustment of the laboratory mill, i.e. an intervention in the grinding system of the laboratory mill to eliminate systematic setpoint-actual value deviations, can be provided, wherein the adjustment can also include a repair of technically defective components and / or their replacement.

[0027] An "evaluation unit" within the meaning of the invention is to be understood in particular as a unit that can be formed by a computing unit and / or a control unit. The evaluation unit can be formed either by a processor alone or, in particular, by a processor and other electronic components, such as a storage device. Particularly advantageously, the evaluation unit can be formed by a microcontroller or a digital data evaluation unit, wherein an analog-to-digital converter can be connected upstream of the evaluation unit.

[0028] The evaluation unit can be integrated into a housing of the laboratory mill. The evaluation unit can also be formed by a processor with storage means of the calibration sensor unit. Finally, it is possible to provide wired or wireless data transmission between the laboratory mill and an evaluation unit that is spatially and / or functionally separate from the laboratory mill, whereby a computer device can be provided as the evaluation unit.

[0029] The calibration sensor can be connected to the grinding bowl holder and / or the grinding bowl in a non-destructive manner.

[0030] The calibration sensor is advantageously integrated into a calibration standard, in particular wherein the dimensioning and / or external shape and / or the contour of the calibration standard and / or the weight of the calibration standard can correspond at least substantially to the dimensioning and / or the external shape and / or the contour and / or the weight of the grinding bowl, which is designed to be held on and / or in the grinding bowl holder of the laboratory mill.

[0031] In particular, the calibration standard has a housing shaped like a grinding bowl. The calibration sensor can be integrated into the housing. The calibration sensor can be formed either by a processor alone or, in particular, by a process with further electronic components, such as a storage medium. Particularly advantageously, the calibration sensor has a microcontroller or a digital data evaluation which allows the recorded actual values ​​of the movement characteristic to be evaluated independently, in particular to determine a movement profile of the calibration standard. For example, the temporal progression of the acceleration of the calibration standard can be determined in order to create a movement profile. Using the movement profile, maxima and minima of the acceleration can be determined and from this the period and frequency of the oscillating movement of the calibration standard can be determined. The calibration sensor can determine the actual values ​​of the recorded ormeasured movement characteristic and / or actual values ​​of a further movement characteristic determined or derived from the recorded or measured movement characteristic are transmitted to an evaluation unit for a setpoint-actual value comparison.

[0032] The calibration sensor can evaluate the recorded or measured movement characteristic at a high sampling rate. The evaluation result can be transmitted to the evaluation unit at a coarser sampling rate in order to determine or calculate a target value-actual value deviation. Particularly advantageously, the laboratory mill can be connected wired or wirelessly to an evaluation unit that is spatially and / or physically and / or functionally separate from the laboratory mill and can be formed by a computing unit and / or a control unit. Via a data connection between the laboratory mill and the evaluation unit, data of actual values ​​of the recorded or measured movement characteristic or of another movement characteristic determined or derived therefrom is preferably exchanged from the laboratory mill to the evaluation unit.The evaluation unit may have calibration software that generates a start signal that is transmitted to the calibration sensor unit to trigger the actual value measurement by the calibration sensor.

[0033] In a preferred embodiment of the design of the laboratory mill according to the invention, it is provided that the calibration standard can be inserted into the grinding bowl holder and, in particular, can be clamped in and / or on the grinding bowl holder. An outer housing of the calibration standard can have dimensions and / or external shape and / or contour that at least substantially correspond to a dimension and / or external shape and / or contour of a grinding bowl, and / or have a corresponding connection geometry, so that the housing can be inserted into a receiving area of ​​the grinding bowl holder for the grinding bowl, in particular an opening in the grinding bowl holder for the grinding bowl, and can be secured to the grinding bowl holder.

[0034] In this context, the invention also relates to a calibration standard for a laboratory mill of the type mentioned at the outset, comprising at least one calibration sensor for detecting actual values ​​of at least one movement characteristic of the calibration standard during grinding operation, wherein the calibration standard is detachably connectable to a grinding bowl holder of the laboratory mill, in particular clampable in and / or on the grinding bowl holder.

[0035] The calibration standard can, in particular, have a housing that allows the calibration standard to be inserted into the grinding bowl holder like a grinding bowl and / or to be secured, in particular clamped, to the grinding bowl holder, so that the calibration standard is held on the grinding bowl holder during grinding operation and moved by the grinding bowl holder. For this purpose, the outer housing of the calibration standard can be structurally identical, at least substantially with regard to the dimensions, shape, and / or contours relevant to the insertion and / or securing to the grinding bowl holder, to a grinding bowl that can be inserted into the grinding bowl holder and / or secured to and / or in the grinding bowl holder. In this context, the invention can relate to a system comprising at least one laboratory mill of the type according to the invention, a calibration standard according to the invention, and at least one grinding bowl that can be secured in and / or on the grinding bowl holder of the laboratory mill.

[0036] In this context, the invention also relates to a calibration standard for a laboratory mill of the type mentioned at the outset, comprising at least one calibration sensor for detecting actual values ​​of at least one movement characteristic of the calibration standard during grinding operation, wherein the calibration standard is detachably connectable to a grinding bowl holder of the laboratory mill, in particular clampable in and / or on the grinding bowl holder.

[0037] The calibration standard can have a housing and the calibration sensor can be integrated into the housing. A multi-part housing can be provided. Housing parts can be connected to one another using fasteners such as snap-in devices or screws. The calibration sensor can be integrated between connected housing parts, such as two housing halves. By integrating the calibration sensor into the housing of the calibration standard, damage to the calibration sensor during grinding operation is prevented. The calibration sensor can be fixed in the housing in all spatial directions so that relative movements between the calibration sensor and the housing cannot occur during grinding operation. This allows the actual values ​​of the movement characteristic of the calibration standard to be recorded with a high degree of accuracy during grinding operation.In principle, however, it is also possible for the calibration sensor to be inserted into a corresponding sensor receptacle in the housing, accessible from the outside. The sensor receptacle can be open during measurement data acquisition or closed with a cover connected to the housing.

[0038] Furthermore, the dimensions and / or the external shape and / or the contour and / or the weight of the calibration standard can at least substantially correspond to the dimensions and / or the external shape and / or the contour and / or the weight of a grinding bowl that can be inserted into the grinding bowl holder and / or is designed for use with the grinding bowl holder. In particular, the calibration standard is shaped like a grinding bowl. Further advantages will become apparent from the following description of the drawing. The drawing illustrates an exemplary embodiment of the invention. The invention is not limited to the exemplary embodiment shown. They show:

[0039] Fig. 1 is a schematic representation of a measuring and calibration system with at least one laboratory mill and with an evaluation unit spatially separated from the laboratory mill,

[0040] Fig. 2 a calibration standard for the laboratory mill from Fig. 1

[0041] Fig. 3 the calibration standard shown in Fig. 2 after the separation of two housing halves of the calibration standard and

[0042] Fig. 4 shows the movement behavior of a grinding bowl inserted in a grinding bowl holder of the laboratory mill from Fig. 1 during grinding operation.

[0043] Figs. 1 to 3 show a measuring and calibration system comprising a laboratory mill 1, which in the exemplary embodiment is designed as a vibrating mill, a calibration standard 2 for the laboratory mill 1, shown in Figs. 2 and 3, and an evaluation unit 3 spatially separated from the laboratory mill 1, which is connected to the laboratory mill 1 via a data exchange connection 4 for wired or wireless data exchange. The data exchange connection 4 can be an Ethernet connection.

[0044] Not shown in detail is that the laboratory mill 1, designed as a vibratory mill, has a pendulum drive for two grinding bowls 5 that perform circular oscillations in a horizontal position. The pendulum drive can be designed in several parts, with an eccentric shaft rotatably mounted about a vertical eccentric axis and two rockers, each mounted so as to oscillate about a vertical oscillation axis and connected to the eccentric shaft via couplings. Grinding bowl holders 6 for the grinding bowls 5 can be attached to the rockers. Fig. 4 shows the movement sequence during the oscillation of the grinding bowl 5 together with the grinding bowl holder 6 over a period T.

[0045] The laboratory mill 1 comprises a calibration sensor unit 7, shown only schematically in Fig. 1. In the embodiment shown, the calibration sensor unit 7 is formed by the calibration standard 2, which comprises a calibration sensor 8. The calibration standard 2 has two housing halves 9, 10, which can preferably be detachably connected to one another to form a closed housing. The calibration sensor 8 is received and held between the housing halves 9, 10 in a form-fitting and / or force-fitting manner. In particular, the calibration sensor 8 is received in the housing of the calibration standard 2 in such a way that relative movements between the calibration sensor 8 and the housing halves 9, 10 cannot occur. An acceleration sensor is preferably provided as the calibration sensor 8. The calibration sensor 8 has a microcontroller and preferably a data memory.

[0046] The housing of the calibration standard 2, formed from the housing halves 9, 10, has an external shape or contour that corresponds to the external shape or contour of a grinding bowl 5 intended for use with the laboratory mill 1. The determination of the grinding bowl 5 for the laboratory mill 1 results from a shape of the grinding bowl 5 adapted to the grinding bowl holder 6 of the laboratory mill 1. In particular, the grinding bowl 5 must have an external dimension and / or shape that allows the grinding bowl 5 to be clamped or fastened in and / or on the grinding bowl holder 6.

[0047] The calibration standard 2 can thus be inserted into the grinding bowl holder 6 or clamped into the grinding bowl holder 6. When inserted or clamped, the calibration standard 2 moves with the grinding bowl holder 6 during operation of the laboratory mill 1. The calibration standard then performs circular oscillations in a horizontal plane.

[0048] The calibration sensor 8 is designed to detect the changing acceleration of the calibration standard 2 during grinding operation as a movement characteristic of the calibration standard 2. During the movement of the calibration standard 2, the acceleration a is recorded. As can be seen from Fig. 4, the acceleration a of the calibration standard 2 behaves sinusoidally. At the reversal points 11, 12 of the movement of the calibration standard 2, the acceleration a is at its highest. During a run-up phase I, the frequency of the movement of the calibration standard 2 increases and is non-uniform. At an oscillation frequency of 30 Hz, for example, the period T for one revolution of the calibration standard is 2 1 / 30 of a second.

[0049] As soon as a maximum frequency of, for example, 30 Hz is reached, the period T is theoretically constant. At this point in time, the period T for one revolution of the calibration standard 2 can be calculated using the zero crossings 13 (see Fig. 4). At the zero crossing 13 of the movement, the acceleration reaches the value zero. One revolution of the calibration standard 2 describes the oscillation period of the movement of the calibration standard 2 together with the grinding bowl holder 6 during grinding operation, starting from a first zero crossing 13, via a first reversal point 11, via a middle second zero crossing 13 and a second reversal point 12 until the second outer zero crossing 13 is reached. The time interval between two zero crossings 13 corresponds to half the period. From this, the total period can be determined.The frequency is then related to the period duration via the mathematical relationship f = 1 / T and can thus be determined. The deviation of the actual frequency from the target frequency, for example, 30 Hz, can be determined and is then the result of a calibration of Laboratory Mill 1 with regard to frequency as a motion characteristic.

[0050] In the embodiment shown, the deviation of the actual frequency from the target frequency, and thus the calibration result, is determined on the evaluation unit 3, which is formed by a computer device on which calibration software is installed. The calibration sensor 8 records the temporal progression of the acceleration and independently evaluates the vibration behavior. Maxima and minima of the acceleration are determined based on a movement profile. As a result of the evaluation, the calibration sensor transmits the actual frequencies of the vibration movement to the evaluation unit 3, which then determines the deviation of the actual frequency from the target frequency.

[0051] List of reference symbols:

[0052] 1 laboratory mill 10 8 calibration sensor

[0053] 2 Calibration standard 9 Housing half 3 Evaluation unit 10 Housing half

[0054] 4 Data exchange connection 11 Turning point

[0055] 5 grinding bowl 12 reversal point

[0056] 6 Grinding bowl holder 15 13 Zero crossing

[0057] 7 Calibration sensor unit

Claims

Patent claims:

1. Laboratory mill (1), in particular a vibrating mill and / or ball mill, such as a centrifugal ball mill and / or planetary ball mill, on a laboratory scale, with at least one grinding bowl holder (6) for at least one grinding bowl (5) and with at least one calibration sensor unit (7) with at least one calibration sensor (8), wherein the calibration sensor (8) is arranged spatially adjacent to the grinding bowl holder (6) during the grinding operation and wherein the calibration sensor (8) detects at least one movement characteristic during the grinding operation.

2. Laboratory mill (1) according to claim 1, characterized in that the calibration sensor (8) is a motion sensor which detects a movement and / or an acceleration.

3. Laboratory mill (1) according to claim 1 or 2, characterized in that the calibration sensor (8) is held and / or fastened to the grinding bowl holder (6) and / or to the grinding bowl (5) and / or to a calibration standard (2) held on the grinding bowl holder (6).

4. Laboratory mill (1) according to one of the preceding claims, characterized in that an evaluation unit (3) is provided for evaluating and / or logging movement parameters detected by the calibration sensor unit (7), in particular for determining a temporal course of the movement parameters.

5. Laboratory mill (1) according to one of the preceding claims, characterized in that the evaluation unit (7) is designed to determine a target value-actual value deviation of the movement characteristic detected during the grinding operation and / or a further movement characteristic derived therefrom from a predetermined target movement characteristic and / or from a sensor of a control and / or regulating device of the laboratory mill (1) reported back.

6. Laboratory mill (1) according to one of the preceding claims, characterized in that a calibration standard (2) is provided which has the calibration sensor (8), wherein the calibration standard (8) is designed for fastening to and / or in the grinding bowl holder (6), in particular for insertion into the grinding bowl holder (6) and / or for clamping in and / or on the grinding bowl holder (6).

7. Calibration standard (2) for a laboratory mill (1), in particular a vibrating mill and / or ball mill, such as a centrifugal ball mill and / or planetary ball mill, in particular for a laboratory mill (1) with at least one calibration sensor (8) for detecting at least one movement characteristic of the calibration standard (2) during grinding operation, wherein the calibration standard (2) is detachably connectable to a grinding bowl holder (6) of the laboratory mill (1), in particular clampable in and / or on the grinding bowl holder (6).

8. Calibration standard (2) according to claim 7, characterized in that the calibration standard (2) has a housing and the calibration sensor (8) is integrated into the housing.

9. Calibration standard (2) according to claim 7 or 8, characterized in that the dimensioning and / or the external shape and / or the contour and / or the weight of the calibration standard (2) corresponds to the dimensioning and / or external shape and / or contour and / or the weight of a grinding bowl (5) that can be inserted into the grinding bowl holder (6) and / or held on the grinding bowl holder (6).

10. Method for calibrating a laboratory mill (1), in particular a vibrating mill and / or ball mill, such as a centrifugal ball mill and / or planetary ball mill, on a laboratory scale, wherein at least one movement characteristic is recorded during the grinding operation using at least one calibration sensor arranged spatially adjacent to the grinding bowl holder (6) during the grinding operation, and that for the calibration a setpoint-actual value deviation of the recorded actual movement characteristic and / or a further actual movement characteristic derived therefrom from a predetermined setpoint movement characteristic and / or reported back by a sensor of a control and / or regulating device of the laboratory mill (1) is automatically determined.

11. Measuring and calibration system with at least one laboratory mill (1) according to one of the preceding claims 1 to 6 and with a calibration standard (2) for a laboratory mill (1) according to one of the preceding claims 7 to 9 and / or with an evaluation unit (3) spatially separated from the laboratory mill (1).

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