Laborschwingmühle

Abstract

Laboratory vibratory mill (1) with at least one vibratory mounting for grinding cups (7, 8) for at least one grinding cup (2, 3) and with a temperature control device for temperature control of the grinding cup (2, 3) by supplying and / or discharging a liquid or gaseous temperature control medium via at least one temperature control line (16, 17) to the grinding cup holder (7, 8), characterized in that the grinding cup holder (7, 8) has at least one heat transfer element (20) connected to the temperature control line (16, 17), wherein the heat transfer element (20) has at least one media channel (23) for conveying the temperature control medium, and wherein the temperature control of a grinding cup (2, 3) held on and / or in the grinding cup holder (7, 8) is effected by heat transfer between the temperature control medium guided in the media channel (23) and the grinding cup (2, 3) via a wall of the heat transfer element (20). this is doneand wherein the heat transfer element (20) is designed as a flat tempering plate and the grinding cup (2, 3) can be placed on the tempering plate with a bottom or side surface of the grinding cup (2, 3) and / or can be placed laterally against the tempering plate.

Description

[0001] The invention relates to a laboratory vibratory mill with at least one vibratory mounting for a grinding cup and with a temperature control device for temperature control, i.e. cooling and / or heating, of the grinding cup by supplying and / or draining a liquid or gaseous temperature control medium via at least one temperature control line to or from the grinding cup holder.

[0002] In laboratory vibratory mills, it is known to induce additional embrittlement of particularly brittle materials by cooling them with liquid nitrogen to efficiently grind them. In known methods, cooling is achieved, for example, by immersing the grinding jar in liquid nitrogen, which floods a grinding jar holder. For this to work, the liquid nitrogen must be continuously supplied to and removed from the grinding jar holder. In this context, it is known to supply the liquid or gaseous medium, such as nitrogen, using appropriately arranged flexible hoses. These hoses are attached directly to the grinding jar holder, thus creating a fluid connection between the holder and the grinding jar.

[0003] Besides nitrogen applications, other applications utilize the short-term, local release of large amounts of energy during the grinding process to initiate chemical reactions. Depending on the reactions occurring, the grinding jar may need to be cooled or heated. This also requires a continuous supply of a medium to regulate the temperature of the reaction chamber.

[0004] From EP 2 391 454 B1, a laboratory mill with rotary unions for the grinding jars supplied with a medium is known. Here, it is provided that two temperature control lines for the supply and discharge of the medium are connected to each grinding jar, and both temperature control lines are routed via the rotary union. The stationary part of the rotary union has two external connections for the stationary temperature control lines of the laboratory mill, and the movable part of the rotary union has two internal connections for the temperature control lines leading to the grinding jar.

[0005] According to the laboratory mill known from EP 2 391 454 B1, liquid nitrogen is fed into the rotary union via a nitrogen line and a switching valve, and then into a connection. It exits the rotary union via a supply line connected to the connection. The nitrogen flow is then directed to the grinding bowl holder and from there back to the moving part of the rotary union. Finally, it passes through the stationary part of the rotary union and a return line connected to it into a collection vessel. As soon as a sensor located on the collection vessel comes into contact with liquid nitrogen, the switching valve closes. Once enough nitrogen has evaporated so that the sensor is no longer wetted, the switching valve opens again. This ensures a continuous supply of liquid nitrogen throughout the grinding process.

[0006] To cool the well-known laboratory mill, the grinding jar holder is flooded with nitrogen, and the grinding jar inside is surrounded by liquid nitrogen. This results in direct contact between the temperature control medium and the grinding jar. Furthermore, the grinding jar is always cooled to its maximum temperature by being flooded with liquid nitrogen.

[0007] From EP 2 861 350 A1, a cooling system for a grinding bowl during the operation of a ball mill is known, wherein two eccentric shafts are designed as hollow shafts with an inner bore. Accordingly, cavities are formed in two opposing connection areas and in a connecting central area of ​​a lower part of each grinding bowl holder. These cavities are connected to the bores of the two eccentric shafts by means of a sealing element fixed at the upper end of each eccentric shaft and a sealing surface formed on the grinding bowl holder, acting as a counter-seal to the sealing element. Thus, a gaseous or liquid cooling medium introduced into one of the two eccentric shafts can flow via the associated eccentric shaft and the cavities arranged in the lower part to the opposite eccentric shaft connected to the grinding bowl holder, and can also flow out in this eccentric shaft.By appropriately shaping the central area of ​​the upper part of each grinding bowl holder and creating a cavity within it, which is connected to the cavities of the lower part, it is ensured that the upper part of each holder is also permeated by the coolant introduced into the lower part of the grinding bowl holder. In this way, the grinding bowl is enclosed by cooled components, so that the temperature level generated in the grinding bowl during the grinding process can be limited.

[0008] The object of the present invention is to provide a laboratory vibratory mill with the features mentioned above, which allows the temperature control of the grinding bowl or a sample held in a grinding chamber of the grinding bowl using different temperature control media in a structurally simple manner, wherein direct contact between the grinding bowl and the temperature control medium does not occur during a grinding process. Furthermore, it is an object of the present invention to design the temperature control such that the heat energy dissipated during cooling of the grinding bowl and / or the heat energy supplied during heating of the grinding bowl is adapted to the actual requirements to the greatest extent possible.

[0009] The aforementioned problems are solved by a laboratory vibratory mill with the features of claim 1. Advantageous embodiments of the invention are the subject of the dependent claims.

[0010] According to the invention, the grinding cup holder has at least one heat transfer element connected to the temperature control line, wherein the heat transfer element has at least one media channel for conveying the temperature control medium, and wherein the temperature control of a grinding cup held on and / or in the grinding cup holder is effected by heat transfer between the temperature control medium guided in the media channel and the grinding cup via a wall of the heat transfer element. The invention is based on the fundamental idea of ​​providing a separate component of the grinding cup holder and / or, in the simplest case, a section and / or area of ​​the grinding cup holder for heat transfer between the temperature control medium and the grinding cup. This enables a design of the grinding cup holder in which there is no direct contact or touching of the grinding cup with the temperature control medium during temperature control.Furthermore, media losses into the environment are prevented. The temperature control medium is guided in a media channel, which is preferably formed in the heat transfer element and is hermetically sealed from the grinding bowl, and in particular from the environment. According to the invention, the heat transfer element is flushed with a liquid or gaseous medium for energy removal from the grinding bowl or for energy supply to the grinding bowl.

[0011] Furthermore, the routing of the temperature control medium within the media channel allows for the use of various gaseous or liquid cooling media for temperature control of the grinding bowl. These cooling media can include, for example, water, thermal oils, or liquid nitrogen. Liquid helium can also be used as a cooling medium. The cooling concept according to the invention can be implemented with any liquid or gaseous cooling media.

[0012] By changing the volume flow rate of the temperature control medium in the media channel and / or the temperature of the temperature control medium, the amount of energy supplied or removed during temperature control can be easily adjusted to the actual requirements of the sample.

[0013] The temperature control line is connected to a temperature control device, which is designed to provide a temperature control medium that may be cooled or heated, to convey the temperature control medium to a grinding cup holder, to drain the temperature control medium from the grinding cup holder, and, if necessary, to dispose of the temperature control medium.

[0014] The heat transfer element can be connected to at least two temperature control lines for supplying the temperature control medium to the heat transfer element and for discharging the temperature control medium from the heat transfer element. Preferably, the media routing via the temperature control lines and the media channel within the heat transfer element is closed to the environment.

[0015] It is advantageous if temperature control is achieved by heat transfer between the temperature control medium and the grinding bowl via contact surfaces of the heat transfer element and the grinding bowl that preferably directly touch each other. Preferably, the heat transfer occurs via metallic contact surfaces. This ensures good heat transfer. The contact surfaces can be ground or finely milled and have a low roughness to improve heat transfer. It is also possible to arrange a heat transfer medium, such as thermal paste, a thermal pad, or even a metallic foil, between the heat transfer element and the grinding bowl to further improve heat transfer.

[0016] A particularly preferred embodiment is one in which the heat transfer element and the grinding bowl are in essentially full contact with each other in the area of ​​the contact surfaces. This is also done to improve the heat transfer between the heat transfer element and the grinding bowl.

[0017] The heat transfer between the heat transfer element and the grinding bowl can essentially occur exclusively through heat conduction via the contact surfaces of the heat transfer element and the grinding bowl. However, an embodiment can be implemented in which a liquid heat transfer medium, such as a thermal oil, is arranged between the heat transfer element and the grinding bowl, so that convective heat transfer between the heat transfer element and the grinding bowl is not fundamentally excluded.

[0018] A structurally simple embodiment of the invention provides a heat transfer element designed as a flat tempering plate, wherein the grinding cup, when attached to the grinding cup holder, can be placed on the tempering plate and / or laterally against the tempering plate, with a bottom or side surface of the grinding cup. The heat transfer element thus fulfills a dual function. Firstly, it serves for heat transfer. Secondly, the tempering plate ensures a stable and fixed arrangement of the grinding cup in and / or on the grinding cup holder.

[0019] To ensure good heat transfer between the grinding cup holder and the grinding cup, the grinding cup holder can be designed to clamp the grinding cup against the heat transfer element. Preferably, the grinding cup is clamped against the heat transfer element when it is clamped in and / or on the grinding cup holder. During clamping in and / or on the grinding cup holder, the grinding cup can be moved in a first clamping direction. This movement can automatically cause the grinding cup to move in a second clamping direction and clamp against the heat transfer element due to force redirection. For this purpose, the grinding cup holder can have appropriately designed projections or geometries that act against the grinding cup when it is clamped, moving it in the second clamping direction.The first clamping direction and the second clamping direction can be orthogonal to each other, whereby, for example, the grinding cup is moved horizontally during clamping in and / or on the grinding cup holder and automatically in a vertical direction by force redirection in order to move the grinding cup against the heat transfer element until the grinding cup rests against the heat transfer element and is clamped.

[0020] The heat transfer element can be formed by two permanently and firmly connected, preferably welded, preferably flat, plate-shaped wall sections, with the media channel located between the connected wall sections. The media channel can be formed by milled flow channels in one wall section, with the other wall section then serving only to cover the flow channels. Alternatively, the heat transfer element can also have bores as media channels in a single block or plate of material. Manufacturing the heat transfer element by 3D printing is also possible.

[0021] According to one embodiment, the invention also relates to a tempering method for tempering a grinding bowl in a vibrating mill according to the invention.

[0022] To solve the aforementioned problem, this embodiment provides a measuring, control, and / or regulating device for the preferably automatic control and / or regulation of the temperature of the grinding bowl holder and / or the grinding bowl itself, and / or for the control and / or regulation of the temperature in a grinding chamber of the grinding bowl. Closed-loop control is also preferably possible. Temperature measurement is preferably performed in close proximity to the grinding vessel using at least one temperature sensor. The control achieved through the proximity of at least one temperature sensor to the grinding vessel exhibits lower control inertia, thus increasing the precision and speed of the control. Temperatures can be controlled particularly preferably using a PID controller.In this context, at least one temperature measuring element, in particular a temperature sensor, is provided, arranged on the grinding bowl holder and / or in and / or on the grinding bowl and / or on and / or in a temperature control line for a temperature control medium. The temperature sensor can also be installed in the grinding chamber to enable in-situ temperature monitoring of the grinding sample. Thus, the temperature sensor enables temperature monitoring of the grinding vessel. The measured temperature can be used as input for a process controller.

[0023] The temperature control, i.e., the cooling and / or heating, of the grinding bowl can be achieved, as described above, with a temperature control device by supplying and / or discharging a liquid or gaseous temperature control medium, in particular liquid nitrogen, via the temperature control line to the grinding bowl holder and / or directly to the grinding bowl. The temperature can be controlled and / or regulated, in particular, by changing the volume flow rate of the temperature control medium supplied to the grinding bowl holder and / or the grinding bowl as a function of a measured temperature and / or by directly changing the temperature of the temperature control medium through appropriate pre-cooling or pre-heating of the temperature control medium. This aspect of the invention enables, for the first time in the prior art, the adaptation of the energy quantities transferred during temperature control to the actual demand, i.e.,The cooling or heating of the temperature control medium is adapted to the specific amounts of heat released during the grinding of a sample or required in connection with the grinding of the sample. A temperature control and / or regulation system is particularly preferred, allowing stepless adjustment and / or regulation of the temperature of the grinding bowl holder and / or the grinding bowl itself.

[0024] Temperature control can be achieved by a preferably timed supply of liquid nitrogen, whereby a nitrogen stream is directed to the grinding bowl holder and / or the grinding bowl and from there returned via a return line to a collection vessel. A temperature sensor can be provided on and / or in the collection vessel to detect the liquid nitrogen level in the vessel via temperature measurement. If nitrogen is detected, a switching valve in the supply line can be closed. Once enough nitrogen has evaporated for the temperature sensor to show a significant temperature drop and / or to no longer be in contact with nitrogen, the switching valve can be opened again to supply nitrogen once more via the supply line to the grinding bowl holder and / or the grinding bowl. Nitrogen detection is thus achieved via temperature measurement.However, it is not out of the question that a sensor is also provided that closes the switching valve when it comes into contact with liquid nitrogen.

[0025] According to the invention, for temperature control of the grinding cup holder and / or the grinding cup, a temperature at the grinding cup holder and / or in and / or on the grinding cup and / or on and / or in a temperature control line for the temperature control medium is measured and controlled and / or regulated.

[0026] In a laboratory vibratory mill with the aforementioned features, wherein the grinding jar holder has a heat transfer element connected to the temperature control line, at least one temperature sensor can advantageously be arranged on and / or in the heat transfer element. Preferably, the temperature sensor engages in a media channel formed in the heat transfer element and is surrounded by the temperature control medium flowing in the media channel during temperature measurement. By measuring the temperature of the temperature control medium inside the heat transfer element, a specific target temperature can be set or regulated with high accuracy. The temperature sensor enables temperature monitoring of the grinding jar holder and thus also of the grinding jar. However, temperature measurement can also be performed directly on the grinding jar and / or in a grinding chamber of the grinding jar.This allows for direct temperature monitoring of a sample located in the grinding chamber.

[0027] The measured temperatures can be used as input values ​​for a process controller in a measurement, control, and regulation system. Due to the proximity of the temperature measurement to the grinding vessel, lower control inertia can be achieved in temperature control, thus increasing the precision and speed of the control.

[0028] In a laboratory mill with multiple grinding jar holders, the measuring, control, and / or regulating device can be designed to independently control and / or regulate the temperatures at the grinding jar holders and / or in and / or on the grinding jars. This allows the temperatures in the grinding jars to be controlled independently and enables the amount of heat to be adjusted even more precisely to the actual heat requirement by either dissipating from or supplying the respective grinding jar.

[0029] The drawing shows exemplary embodiments of the invention, which are described below. Fig. 1 a perspective view of a laboratory vibratory mill according to the invention, Fig. 2 a top view of the laboratory mill Fig. 1, Fig. 3 a view of the laboratory mill from Fig. 1 from the bottom, Fig. 4 an enlarged partial view of the right grinding cup holder of the in Fig. 3 laboratory vibrating mills shown, Fig. 5 the perspective view of the grinding cup holder from Fig. 4, wherein the grinding cup holder has a two-part plate-shaped heat transfer element and an outer part of the heat transfer element is hidden on the connection side of the heat transfer element, Fig. 6 a perspective view of the two-part heat transfer element of the in the Fig. 4 and Fig. 5 enlarged grinding cup holders shown, Fig. 7 a perspective view of the in Fig. 2 grinding cup holders shown on the right in a top view, before a grinding cup is inserted into the grinding cup holder, Fig. 8 a schematic process diagram of a first embodiment of a process according to the invention for temperature control of grinding cups in a vibrating mill and Fig. 9 a schematic process diagram of an alternative embodiment of a method for temperature control of the grinding cups in a vibrating mill.

[0030] Fig. Figure 1 shows a top view of a vibratory mill 1 for two grinding cups 2, 3 performing arc-shaped oscillations in a horizontal position. The vibratory drive of the mill 1 is a multi-part design with an eccentric shaft 4 rotatably mounted about a vertical eccentric axis and with two rocker arms 5, 6, each mounted to oscillate about vertical axes and connected to the eccentric shaft 4 via couplings. Grinding cup holders 7, 8 for the grinding cups 2, 3 are attached to the rocker arms 5, 6. A motor unit 10, coupled to the eccentric shaft 4 via a V-belt 9, is provided for torque transmission. The eccentric shaft 4 is rotatably mounted on a base plate 11. Two bearing bolts 12, 13 are also attached to the base plate 11, around which the rocker arms 5, 6 are rotatably mounted. Finally, the motor unit 10 is arranged on the base plate 11.The eccentric shaft 4, the bearing bolts 12, 13 and the motor unit 10 together with the base plate 11 form a unit which can rest on a floor or surface via damping elements.

[0031] The motor unit 10 transmits torque to the eccentric shaft 4 via the V-belt 9. A rotary motion of the eccentric shaft 4 is converted into a vibration motion of the rocker arms 5, 6 via the couplings. The vibration frequency can be between 3 and 50 Hz, preferably up to 35 Hz. The oscillation displacement (twice the amplitude deflection) of the grinding bowl can be between 20 and 50 mm, preferably between 20 and 30 mm.

[0032] Temperature control, i.e., cooling or heating, of the grinding bowls 2, 3 is possible via a temperature control device (not shown in detail). Each grinding bowl holder 7, 8 is connected to two temperature control lines 16, 17 for transporting a temperature control medium, which may be liquid or gaseous, from a stationary part 14, 15 of the vibrating mill 1 to a grinding bowl holder 7, 8, and for discharging the medium from the respective grinding bowl holder 7, 8 to the stationary part 14, 15. One of the two temperature control lines 16, 17 is for supplying, and the other for discharging, a gas or liquid temperature control medium, in particular liquid nitrogen, to the respective grinding bowl holder 7, 8.

[0033] The temperature control lines 16, 17 are preferably designed as continuous, uninterrupted pipes. The temperature control lines 16, 17 can, for example, be made of stainless steel or plastic, or may consist of stainless steel and / or plastic.

[0034] The design of the pipe routing is identical for both grinding cup holders 7 and 8, so only one pipe routing is described below as an example. The pipe arrangement with the temperature control lines 16 and 17 of one grinding cup holder 7 is mirror-symmetrical to the pipe routing of the second grinding cup holder 8.

[0035] To compensate for relative movements that occur between a grinding bowl holder 7, 8 and the stationary part 14, 15 associated with the temperature control lines 16, 17 during operation of the vibratory mill 1, each line 16, 17 has a compensating element 18, 19. Each line 16, 17 is designed as a rigid pipe along its entire length, with the compensating element 18, 19 being formed by a pipe section of the line 16, 17.

[0036] During operation of the vibrating mill 1, the relative movements cause an oscillating deformation of the pipe sections forming the compensating elements 18, 19, whereby the pipe sections of the respective pipe 16, 17 adjacent to the compensating elements 18, 19 are deformed comparatively less. The design of the compensating elements 18, 19 as rigid pipe sections enables the compensation of relative movements without the need for pipe sections that are rotatably and / or pivotably connected relative to each other. In particular, it is not necessary to use rotary feedthroughs known from the prior art to compensate for relative movements, thus ensuring a hermetically sealed, uninterrupted connection and permanently leak-free transport of the temperature control medium between the grinding bucket holders 7, 8 and the stationary parts 14, 15 in a simple manner.In particular, unlike rotary feedthroughs, it is not necessary to use sealing elements to compensate for relative movements.

[0037] For connecting the temperature control lines 16, 17 to the grinding cup holders 7, 8 on the one hand and to the stationary parts 14, 15 on the other, connection and accessory components known from the prior art can be provided. The connection of the temperature control lines themselves, i.e., decoupled from the compensation of relative movements, can be effected using sealant to enable a sealing connection between the respective line 16, 17 and the grinding cup holder 7, 8 on the one hand, and the stationary part 14, 15 on the other.

[0038] In the Fig. 4 and Fig. 5 is the grinding cup holder 7 in the view according to Fig. Figure 3 is shown enlarged. Not shown is the temperature control device for maintaining the temperature of the grinding bowl 2 by supplying and / or discharging a liquid or gaseous temperature control medium via the temperature control lines 16, 17 to the grinding bowl holder 7, 8. In the simplest case, the temperature control device comprises a conveying means for the temperature control medium and a container for holding the temperature control medium. Preferably, a closed circuit of the temperature control medium via the temperature control lines 16, 17 is provided.

[0039] Each grinding cup holder 7, 8 has a heat transfer element 20 connected to the temperature control lines 16, 17. In the illustrated embodiment, the heat transfer element 20 is plate-shaped and has an inner first plate part 21 and an outer second plate part 22 on the connection side of the heat transfer element 20. The temperature control lines 16, 17 are connected to the plate part 21 on the outside of the outer plate part 22 by means of connecting elements known per se from the prior art.

[0040] Fig. Figure 5 shows the grinding cup holder 7 from Fig. 4, with the outer plate section 22 hidden. This provides a clear view of the inner plate section 21, in which a media channel 23 is formed for the flow of the temperature control medium. By connecting the plate sections 21 and 22, which can be done by welding or bonding, the media channel 23 is hermetically sealed from the environment. Screwing the plate sections 21 and 22 together is also possible.

[0041] During the temperature control of a grinding bowl 2, 3, i.e., during the passage of a cold, warm, or hot temperature control medium through the temperature control lines 16, 17, heat transfer occurs between the temperature control medium guided in the media channel 23 and the grinding bowl 2 via a wall of the heat transfer element 20, in this case via the inner plate section 21. Guiding the temperature control medium in the media channel 23 allows for temperature control of the grinding bowl 2, 3 without it coming into contact with the temperature control medium, thus eliminating any contact and the risk of contamination. The media channel 23 has a meandering shape and terminates in two blind holes 23a, 23b. Furthermore, ring milling 23c is provided to improve heat transfer.

[0042] The heat transfer between the temperature control medium and the grinding cup 2, 3 takes place via mutually contacting metallic surfaces of the heat transfer element 10 and the grinding cup 2, wherein in Fig. 7 the grinding cup holder 8 out Fig. 2 after the removal of the grinding cup 3. As can be seen from Fig. As shown in figure 7, a flat contact surface 24 is provided on the upper side, or the outer side of the plate part 21 facing the grinding cup 2. During the grinding process, this surface essentially rests against an outer bottom surface of the grinding cup 2 over its entire area. In the illustrated embodiment, heat transfer between the heat transfer element 20 and the grinding cup 2 occurs exclusively by conduction via the contact surface 24 of the plate part 21 and the bottom surface of the grinding cup 2.

[0043] The grinding cup holder 7, 8 of the laboratory mill 1 shown each has a retaining bracket 25 rigidly connected to a rocker arm 5, 6, which interacts with a horizontally adjustable retaining bracket 26. By adjusting the clamping screw 27, the outer retaining bracket 26 can be clamped against the inner retaining bracket 25, thus clamping a grinding cup 2, 3 horizontally between the retaining brackets 25, 26.

[0044] Clamping pieces 28 are provided in the corner areas of the outer retaining bracket 26. When the grinding bowl 2, 3 is clamped horizontally in the grinding bowl holder 7, 8, these clamping pieces cause the grinding bowl 2, 3 to be automatically pressed downwards against the inner plate part 21 of the heat transfer element 20 by force redirection. For this purpose, the clamping pieces 28 can be chamfered on the inner side facing the plate part 21 or have a corresponding clamping angle.

[0045] Preferably, two temperature sensors 29 are arranged in the immediate vicinity of the grinding vessel, namely on each heat transfer element 20, for measuring the temperature at the heat transfer element 20. The temperature sensors 29 are connected via electrical lines (not shown) to an evaluation unit of a measuring, control, and / or regulating device (not shown) for the automatic control of the temperature of the grinding vessel holder 6, 7. The temperature sensors 29 can be designed to measure the temperature of a plate section 21, 22 and / or, via bores in the outer plate section 22 of the heat transfer element 20, can extend into the area of ​​the media channel 23, so that a sensor of the respective temperature sensor 29 engages in or is surrounded by the temperature control medium guided inside the media channel 23.This makes it possible to directly measure the temperature of the temperature control medium in the area of ​​the grinding bowl holder 6, 7. By arranging the temperature sensors 29 in close proximity to the grinding bowl 2, 3, temperature control of the temperatures at and / or in the grinding bowl 2, 3 is possible with low control inertia, thus achieving high precision and speed of temperature control.

[0046] In an embodiment of a vibrating mill 1 (not shown), a temperature sensor 29 is provided for each heat transfer element 20. The temperature sensors 29 are connected via electrical lines (not shown) to an evaluation unit of a measuring, control and / or regulating device 30 (not shown) for automatic control of the temperature of the grinding bowl holder 6, 7.

[0047] In the Fig. 8 and Fig. Figure 9 schematically illustrates two alternative methods for temperature control of two grinding jars 2, 3 of a laboratory vibratory mill 1 (not shown in detail). A measuring, control, and / or regulating device 30 is provided for the automatic temperature control of two grinding jar holders 7, 8 of the vibratory mill 1. The temperature control is achieved using at least two temperature sensors 29, which determine the temperatures of two heat transfer elements 20 of the grinding jar holders 7, 8 during operation of the vibratory mill 1 or during a grinding process. During the grinding process, the grinding jars 2, 3 rest on the heat transfer element 20. Heat transfer preferably occurs exclusively by conduction via contact surfaces.

[0048] For the supply and discharge of a liquid or gaseous temperature control medium, in the exemplary embodiments liquid nitrogen, to the heat transfer elements 20 or to the respective grinding bowl holder 7, 8, each grinding bowl holder 7, 8 is connected to two temperature control lines 16, 17. The temperature control lines 16, 17 of a grinding bowl holder 7, 8 are connected to a rotary feedthrough 31 to allow compensation of relative movements between the oscillating grinding bowl 2, 3 and a stationary part of the laboratory mill 1.

[0049] Each rotary union 31 is connected to a supply line 32 and a return line 33 for supplying the temperature control medium from a media container 34, for example, a nitrogen tank, and for discharging the temperature control medium after it has flowed through the heat exchanger element 20 into a disposal device for the temperature control medium, in this case a pressure relief tube 35. Additional temperature sensors 36 are provided for measuring the temperature of the medium in the returns lines 33. These additional temperature sensors 36 serve primarily for fault detection. A measured value associated with each return line 33 allows leakage to be detected for each return line 33, its associated heat transfer element 20, and its associated lines 32 and rotary unions 31. This enables efficient monitoring of proper operation via measured values ​​without the need for physical inspection of the lines.The line to the pressure relief pipe 35 is finally routed via a throttle 37.

[0050] In a preferred embodiment (not shown), the leads 33 are joined together and routed via a throttle 37 to the expansion tube 35. In this embodiment, temperature measurement with at least one sensor 36 is provided after the joining.

[0051] The supply of the temperature control medium from the media container 34 via the supply lines 32 to the respective rotary feedthrough 31 is controlled by a solenoid valve 38 as an actuator of a closed control loop, depending on the temperatures determined at the grinding cup holders 7, 8 by the temperature sensors 29. The solenoid valve 38 is thus designed to effect the pulsed addition or feed of the temperature control medium into the supply lines 32 to the two grinding cup holders 7, 8. The inlet temperature of the medium can be determined by means of a further temperature sensor 39.

[0052] Furthermore, the measuring, control, and / or regulating device 30 includes an evaluation or computing unit (not shown) that compares the measured temperatures with predefined setpoints. Based on this setpoint-actual value comparison, the actuator of the control loop is then actuated. In the illustrated embodiment, the cycling of the solenoid valve 38 is changed accordingly, depending on the setpoint-actual value comparison.

[0053] It goes without saying that the one based on Fig. The described procedure for temperature control of the grinding bowls 2, 3 via the temperature control of the grinding bowl holders 7, 8 can also be implemented in a corresponding manner when using other temperature control media. Furthermore, the described control method also allows the temperature of the grinding bowls 2, 3 to be directly determined and controlled. For this purpose, temperature sensors can be arranged on and / or in the grinding bowls 2, 3.

[0054] Data transmission between the sensors and an evaluation unit of the measuring, control and / or regulating device can be wired or wireless, for example via radio.

[0055] In Fig. Figure 9 schematically shows the process flow for an alternative method for temperature control of the grinding bowls 2, 3. In contrast to the method in Fig. The procedure shown in section 8 and described above is in accordance with Fig. 9 Two solenoid valves 38 are provided to adjust the timing of each solenoid valve 38 depending on the temperature measured at the respective grinding cup holder 7, 8. This makes it possible to cool or heat the grinding cups 2, 3 to different degrees and to control the temperatures in and / or on the grinding cups independently of each other. Reference symbol list: 1 Swing mill 2 grinding cups 3 grinding cups 4 eccentric shaft 5 swing arm 6 Swingarm 7 Grinding cup holder 8 Grinding cup holder 9 V-belts 10 motor units 11 Base plate 12 bearing bolts 13 bearing bolts 14 stationary part 15 stationary part 16 Temperature control lines 17 Temperature control line 18 Compensating element 19 Compensating element 20 Heat transfer element 21 plate part 22 plate part 23 Media Channel 23a Dead end 23b Blind hole 23c ring milling 24 contact area 25 retaining brackets 26 retaining brackets 27 Tensioning screw 28 clamping piece 29 Sensor 30 Measuring, control and / or regulating device 31 Rotary feedthrough 32 Supply line 33 Derivative 34 media containers 35 Relaxation tube 36 Sensor 37 Throttle 38 Solenoid valve 39 Sensor

Claims

[1] Laboratory vibratory mill (1) with at least one vibratory mounting grinding cup holder (7, 8) for at least one grinding cup (2, 3) and with a temperature control device for temperature control of the grinding cup (2, 3) by supply and / or discharge of a liquid or gaseous temperature control medium via at least one temperature control line (16, 17) to the grinding cup holder (7, 8), characterized by, that the grinding cup holder (7, 8) has at least one heat transfer element (20) connected to the temperature control line (16, 17), wherein the heat transfer element (20) has at least one media channel (23) for conveying the temperature control medium, and wherein the temperature control of a grinding cup (2, 3) held on and / or in the grinding cup holder (7, 8) is effected by heat transfer between the temperature control medium guided in the media channel (23) and the grinding cup (2, 3) via a wall of the heat transfer element (20), and wherein the heat transfer element (20) is designed as a flat temperature control plate, and the grinding cup (2, 3) can be placed on the temperature control plate with a bottom or side surface of the grinding cup (2, 3) and / or can be placed laterally against the temperature control plate. [2] Laboratory vibrating mill (1) according to claim 1, characterized by, that the grinding cup holder (7, 8) is designed to temper the grinding cup (2, 3) without contact with the tempering medium. [3] Laboratory vibrating mill (1) according to claim 1 or 2, characterized by , that the temperature control is carried out by heat transfer between the temperature control medium and the grinding cup (2, 3) via directly adjacent contact surfaces (24) of the heat transfer element (20) and the grinding cup (2, 3). [4] Laboratory vibratory mill (1) according to any one of the preceding claims, characterized by , that the heat transfer element (20) and the grinding cup (2, 3) are in essentially full contact with each other in the area of ​​the contact surfaces (24). [5] Laboratory vibratory mill (1) according to any one of the preceding claims, characterized by, that the heat transfer between the heat transfer element (20) and the grinding cup (2, 3) takes place essentially exclusively by heat conduction via the contact surfaces (24) of the heat transfer element (20) and the grinding cup (2, 3). [6] Laboratory vibratory mill (1) according to any one of the preceding claims, characterized by , that the grinding cup holder (7, 8) is designed to clamp the grinding cup (2, 3) against the heat transfer element (20). [7] Laboratory vibratory mill (1) according to any one of the preceding claims, characterized by , that a measuring, control and / or regulating device is provided for preferably automatic control and / or regulation of the temperature of the grinding cup holder (7, 8) and / or the grinding cup (2, 3) and / or the temperature in a grinding chamber of the grinding cup (2, 3). [8] Laboratory vibrating mill according to claim 7, characterized by, that at least two grinding cup holders (7, 8) are provided and that the measuring, control and / or regulating device for independently controlling and / or regulating the temperatures on the grinding cup holders (7, 8) and / or in and / or on the grinding cups (2, 3) is designed. [9] Method for temperature control of a grinding jar (2, 3) during a grinding process in a laboratory vibratory mill (1) according to one of the preceding claims, wherein at least one temperature at the grinding jar holder (7, 8) and / or in and / or on the grinding jar (2, 3) and / or on and / or in a temperature control line (16, 17) for a temperature control medium for temperature control of the grinding jar holder (7, 8) and / or the grinding jar (2, 3) is measured and controlled and / or regulated.

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