Laboratory mill and calibration standard for a laboratory mill

Abstract

Laboratory mill (1), in particular vibrating mill and / or ball mill, such as centrifugal ball mill and / or planetary ball mill, on a laboratory scale, with at least one grinding cup holder (6) for at least one grinding cup (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 cup holder (6) during the grinding operation and wherein the calibration sensor (8) detects at least one motion parameter during the grinding operation, characterized in that a calibration standard (2) is provided which has the calibration sensor (8), wherein the calibration standard (2) is designed for attachment to and / or in the grinding cup holder (6), in particular for insertion into the grinding cup holder (6) and / or for clamping in and / or on the grinding cup holder (6).

Description

[0001] 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.

[0002] Furthermore, the present invention relates to a calibration standard for a laboratory mill of the aforementioned type.

[0003] Furthermore, the present invention relates to a method for calibrating a laboratory mill and a measuring and calibration system.

[0004] 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.

[0005] 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.

[0006] 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.

[0007] 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.

[0008] 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.

[0009] 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.

[0010] 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, due to technical defects, 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.

[0011] 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.

[0012] 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.

[0013] 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 dependent claims.

[0014] 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.

[0015] 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 milling operation of the mill. 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.

[0016] According to the invention, the movement characteristic is such a movement characteristic 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 the grinding operation.

[0017] The calibration sensor unit can comprise any motion sensor that a person skilled in the art would deem appropriate for detecting movement and / or acceleration. Advantageously, the calibration sensor is an acceleration sensor, an optical sensor, and / or a mechanical sensor. The acceleration sensor can be formed, for example, by a MEMS (micro-electro-mechanical sensor), which outputs acceleration in voltage values ​​and makes them detectable for data processing. The optical sensor can function essentially analogously to, for example, an optical computer mouse. The mechanical sensor can be formed by a vibration and / or inclination sensor. The motion parameter can be formed by a voltage parameter, an optical parameter, a parameter representing an angle of inclination, and / or other motion parameters that a person skilled in the art would deem 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 a calibration standard attached to the grinding bowl holder.

[0020] The calibration sensor moves along the grinding bowl holder during grinding operation. By positioning the calibration sensor near 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 motion parameter can be detected with high accuracy.

[0021] An evaluation unit is provided for evaluating and / or logging the movement characteristic measured by the calibration sensor unit, in particular for determining a temporal profile of the movement characteristic. Advantageously, in vibratory mills, a single- or multi-axis profile of the acceleration of the calibration sensor can be provided over a phase of milling operation of a predetermined duration.

[0022] 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.

[0023] 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.

[0024] 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 jar holder and / or at the location of the grinding jar 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.

[0025] The measured value can be calibrated by determining the movement behavior of the calibration sensor during milling operation. For example, in a vibratory mill, the acceleration measured by the calibration sensor can be recorded during the movement of the grinding jar holder. The acceleration is highest at the reversal points of the sensor's movement. The acceleration is sinusoidal. During the vibratory mill's start-up phase, the frequency of the movement increases and becomes irregular.

[0026] Once a maximum frequency is reached, the period remains essentially constant. At this point, the period of the oscillation can be calculated based on the zero crossings (acceleration = zero). The time interval between two zero crossings corresponds to half the period. This allows the total period to be determined. The frequency can be determined from the period and thus also the deviation of the actual frequency from the specified or reported target frequency as a result of the calibration.

[0027] 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.

[0028] 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.

[0029] An "evaluation unit" within the meaning of the invention is understood to mean, in particular, 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, whereby an analog-to-digital converter can be connected upstream of the evaluation unit.

[0030] 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.

[0031] The calibration sensor can be connected to the grinding bowl holder and / or the grinding bowl in a non-destructive manner.

[0032] 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.

[0033] 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.

[0034] The calibration sensor can evaluate the recorded or measured motion parameters at a high sampling rate. The evaluation result can be transmitted to the evaluation unit at a coarser sampling rate to determine or calculate a setpoint-actual value deviation.

[0035] Particularly advantageously, the laboratory mill can be connected, either wired or wirelessly, to an evaluation unit that is spatially and / or physically and / or functionally separate from the laboratory mill, which evaluation unit can be formed by a computing unit and / or a control unit. A data connection between the laboratory mill and the evaluation unit preferably enables data exchange of actual values ​​of the recorded or measured movement characteristic or of a further movement characteristic determined or derived therefrom from the laboratory mill to the evaluation unit. The evaluation unit can 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.

[0036] 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.

[0037] 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.

[0038] 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.

[0039] Furthermore, the dimensions and / or external shape and / or contour and / or weight of the calibration standard can at least substantially correspond to the dimensions and / or external shape and / or contour and / or 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.

[0040] Further advantages will become apparent from the following description of the drawings. The drawings illustrate an embodiment of the invention. The invention is not limited to the illustrated embodiment. They show: Fig. 1 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, Fig. 2 a calibration standard for the laboratory mill Fig. 1 Fig. 3 that in Fig. 2 shown calibration standard after separation of two housing halves of the calibration standard and Fig. 4 the movement behavior of a grinding bowl holder of the laboratory mill from Fig. 1 inserted grinding bowl during grinding operation.

[0041] In the Fig. 1 to 3 is a measuring and calibration system with a laboratory mill 1 designed as a vibrating mill in the embodiment, with a Fig. 2 and Fig. 3, and with 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.

[0042] 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 constructed in several parts, with an eccentric shaft mounted for rotation about a vertical eccentric axis and two rockers, each mounted for oscillation 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.

[0043] The laboratory mill 1 includes a Fig. 1 shows a calibration sensor unit 7, which is shown only schematically. 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.

[0044] 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.

[0045] 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.

[0046] The calibration sensor 8 is designed to detect the changing acceleration of the calibration standard 2 during the 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. For an oscillation frequency of, for example, 30 Hz, the period T for one revolution of the calibration standard is 2 1 / 30 of a second.

[0047] 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 determined using the zero crossings 13 (cf. 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 duration. From this, the total period duration can be deduced. 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 the laboratory mill 1 with regard to the frequency as a movement characteristic.

[0048] 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. List of reference symbols: 1 laboratory mill 2 calibration standards 3 Evaluation unit 4 Data exchange connection 5 grinding bowls 6 Grinding bowl holder 7 Calibration sensor unit 8 Calibration sensor 9 Housing half 10 Housing half 11 Turning point 12 Turning point 13 Zero crossing

Claims

Laboratory mill (1), in particular vibrating mill and / or ball mill, such as 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. 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. 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). 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 progression of the movement parameters. 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). 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). 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). 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. 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). 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 purpose 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 (1) is automatically determined. 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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