Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
  • B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
  • B02C4/00—Crushing or disintegrating by roller mills
  • B02C4/28—Details
  • B02C4/32—Adjusting, applying pressure to, or controlling the distance between, milling members
  • B02C4/36—Adjusting, applying pressure to, or controlling the distance between, milling members in mills specially adapted for paste-like materials
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
  • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
• • A—HUMAN NECESSITIES
  • A23—FOODS OR FOODSTUFFS; TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES
  • A23G—COCOA; COCOA PRODUCTS, e.g. CHOCOLATE; SUBSTITUTES FOR COCOA OR COCOA PRODUCTS; CONFECTIONERY; CHEWING GUM; ICE-CREAM; PREPARATION THEREOF
  • A23G1/00—Cocoa; Cocoa products, e.g. chocolate; Substitutes therefor
  • A23G1/04—Apparatus specially adapted for manufacture or treatment of cocoa or cocoa products
  • A23G1/10—Mixing apparatus; Roller mills for preparing chocolate
  • A23G1/12—Chocolate-refining mills, i.e. roll refiners
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
  • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
  • B22F3/18—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces by using pressure rollers
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
  • G01B11/00—Measuring arrangements characterised by the use of optical techniques
  • G01B11/02—Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness
  • G01B11/06—Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness for measuring thickness ; e.g. of sheet material
  • G01B11/0691—Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness for measuring thickness ; e.g. of sheet material of objects while moving

Definitions

• the invention relates to a rolling mill for the treatment of viscous masses, in particular for comminution and uniform distribution in a binder suspended solid particles.
• Such a rolling mill has at least two rollers rotatably mounted about its longitudinal axes, wherein the axis of rotation of a first roller is mounted stationary and the axis of rotation of a second roller is movably mounted, and at least one pressing device for pressing at least one roller against the other roller.
• the temperatures of the roll surfaces affect the viscosity of the binder, while the gap spacing for a given difference in surface speed significantly affects the shear rate in the nip.
• the shear rate between the rotating rollers and the viscosity of the binder in which the particles are suspended have a decisive influence on the result of the comminution and distribution of the suspended particles.
• the operators of such rolling mills therefore also achieve good product qualities, ie good comminution and uniform distribution of the solid particles suspended in the binder.
• a reproducible adjustment of the roll spacing with usually arranged at both longitudinal ends of the rollers actuators ("watches") is difficult, if only because the wear over time and thus always new settings of the actuators are necessary to longer operating times of the rolling mill to ensure a constant nip.
• the reproducibility is also affected by temperature-induced expansion of the rolls and other rolling mill parts, whereby the mechanical tolerances in general and in particular the roll spacing change over time.
• the invention is therefore based on the object as simple and reproducible monitoring of the operating parameters and in particular to enable the nip in a rolling mill for the treatment of viscous masses.
• a roller of the rolling mill according to the invention is equipped with at least one layer thickness sensor device for detecting the value of the layer thickness of the treated viscous mass on the roller. It has surprisingly been found that for most of the products to be processed there is a relationship between the right one. End of the particle size distribution and the respective layer thicknesses on the respective rolls of a rolling mill.
• the layer thickness sensor device is preferably connected to a display device for displaying the detected value of the layer thickness.
• the current layer thicknesses of the mill can be read by an operator at any time. This can then correct immediately if necessary, for example, manually occurring gap setting and possibly even more mill operating parameters to get back to the desired target layer thickness, which is particularly representative of the product quality.
• online quality control by means of layer thickness measurement is possible.
• the layer thickness sensor device is connected to a measurement data processing device for processing the acquired measurement data.
• the processed measurement data is preferably recorded during mill operation.
• the operating parameter protocols obtained in this way can be evaluated and used to model for optimal processing of different raw materials. In this way, the learning process can be made more transparent and reproducible for different procedural tasks.
• operating parameter patterns are mapped to product parameter patterns.
• Rule packages created which tell the operator how he has to change the operating parameters, so that the best possible product quality, i. a product with product parameters is achieved as close as possible to the target product parameters.
• the rules may e.g. be programmed as intelligent software technologies such as fuzzy logic or neural networks or as a combination of such or other intelligent software technologies. In this way, the behavior of an experienced mill operator and in particular its learning ability can be mimicked.
• the rolling mill according to the invention is also equipped with a control device in addition to the measured data processing device and in particular has a control device.
• the rolling mill controller may preferably control at least one rolling mill operating parameter.
• the mill operator can be assisted in his work, whereby an at least semi-automatic operation of the rolling mill according to the invention takes place.
• the at least one operating parameter may be one of the following parameters:
• the rolling mill according to the invention may be a twin-roll mill.
• a rolling mill according to the invention in the form of a three-roll mill with a first roll, a second roll and a third roll.
• a three-roll mill is particularly well suited for comminution and uniform distribution in a binder suspended solid particles, wherein in the first nip primarily a mixture takes place to achieve the most uniform distribution of the particles in the binder, (distributive effect), while .in the second nip primarily a force on the particles takes place in order to achieve their comminution (dispersive effect).
• control device may control at least one operating parameter of the three-roll mill, the operating parameter preferably being at least one of the following parameters:
• the layer thickness sensor device has a confocal sensor on the surface of the roller associated therewith.
• the confocal sensor works according to the confocal measuring principle (principle several focal points) for distance measurement.
• light having a plurality of discrete frequencies or a continuous frequency spectrum is focused on the measurement surface via a first optical system (lens arrangement) with chromatic aberration.
• the first optic preferably has multiple lenses and achieves controlled chromatic aberration, i. the focal plane of the first optics has one for each frequency or wavelength of the incident light. other distance. from the main plane (or the main planes) of the lens array.
• each frequency or wavelength can be assigned a distance at which the light of the respective frequency or wavelength incident in parallel or in a predetermined diverging beam into the first optical system is imaged at a point in the respective image plane.
• That frequency (or wavelength or light color) is used in this sensor, which focuses exactly on the measurement surface.
• the light reflected from this point of light on the measurement surface is also imaged via a second optics or via the first optics in the opposite direction and optionally via an additional mirror arrangement, preferably a partially transparent mirror arrangement without chromatic aberration on a photosensitive sensor element also as a light point. This recognizes the respective light color of this imaged light spot. By thus identified light color of the point on the sensor element, the distance of the measuring surface of the first optics can be determined.
• the layer thickness sensor device has a capacitive sensor on the surface of its associated roller, wherein the roller is preferably a metal roller.
• the capacitive sensor operates on the capacitive principle. It is located near the surface of the metal roller, so that a capacitance is formed between an electrode of the sensor and the metal surface, the value of which depends on the type of non-conductive material (dielectric) between the sensor electrode and the roller surface.
• the value of the capacitance is influenced by the product layer acting as a dielectric, which adheres to the roll surface. A change in the layer thickness of the product thus leads to a clear change in the capacitance between the sensor and the roll surface.
• the layer thickness sensor device has an additional inductive sensor on the surface of the roller, which is rigidly connected to the confocal and / or capacitive sensor.
• the inductive sensor works on the inductive principle, whereby the change of the inductance of a coil is measured.
• the coil is connected in a circuit together with an AC voltage source.
• a measurement of the alternating voltage between the two coil ends can be concluded due to a change in the amplitude of the AC voltage to a corresponding change in the inductance.
• a coil choke coil
• This core protrudes with its first end out of the first coil end and with its second end out of the second coil end.
• the two from the coil outstanding bobbin ends are located near the roll surface.
• the inductance of the coil depends on the magnetic flux passing through the coil or its core.
• the distance, ie the air gap, between the respective coil core ends and the roll surface changes, so does the magnetic flux through the coil (magnetic ring flux through the magnetic circuit passing through the coil core, the area of the roll surface facing the coil and the two air gaps is formed).
• the coil in the vicinity of the surface of a roll of conductive material, in particular a steel roll, there is a coil which points with one of its coil ends to the roll surface.
• the coil generates an alternating field, which generates eddy currents in the electrically conductive roller surface, which react on the coil and change its inductance.
• the roller is made of a non-ferromagnetic conductive material, there is a damping of the coil and thus a reduction of its inductance.
• the roller is made of a ferromagnetic conductive material, there is a damping of the coil and thus an increase in their inductance.
• the coil is a flat coil with a spiral winding, in particular a printed on a non-conductive film material coil with spiral winding.
• the distance measuring direction of the inductive sensor is aligned parallel to the layer thickness measuring direction of the confocal and / or the capacitive sensor.
• This can be e.g. in that the coil of the inductive sensor and the electrode of the capacitive sensor are arranged concentrically, or that the coil of the inductive sensor and the chromatic aberrative optics (first optics) of the confocal sensor are arranged concentrically.
• the layer thickness sensor device has an NIR sensor on the surface of the roller.
• This type of sensor is particularly well suited for measuring the thickness of a mass on a roller whose surface is non-conductive and in particular consists of a ceramic material.
• the rolls of the rolling mill are made of a ceramic material, or the rolls have a core of metal and a coating of ceramic material.
• the NIR signal is predominantly reflected by the particles of the product layer, penetrating far enough into or penetrating the product layer but hardly reflected by the practically non-conductive ceramic layer.
• the measuring principle is based on the fact that light of the near infrared (NIR, approx. 1-30 ⁇ m) has a penetration depth of several wavelengths.
• NIR near infrared
• the NIR light reflected from the individual molecules (binder molecules and pigment molecules) of the product layer adds to the total intensity of the reflected NIR light and is therefore proportional to the layer thickness, provided that during operation the composition (recipe) of the Layer forming mass remains constant, which corresponds to a practically constant solids content in the binder matrix.
• the NIR layer thickness sensor is used in rolling systems according to the invention, the rollers of which are not made of metal but of ceramic material and thus are generally electrically non-conductive (at least for electrons).
• the use of the capacitive sensor and the inductive sensor is virtually impossible with rolls of non-conductive materials.
• the distance to the product surface is determined by the confocal sensor.
• the confocal sensor uses a light source that emits a light spectrum with different spectral colors and a chromatic aberration optics.
• a triangulation sensor can also be used for this, which preferably uses a monochromatic laser beam.
• Thickness of the product layer is the thickness of the product layer
• the thickness of the product layer is measured by the capacitive sensor.
• NIR sensor can also be used for this, which, like the capacitive sensor, can directly determine the layer thickness.
• the distance to the metallic roller surface is measured by the inductive sensor.
• the object of the present invention is achieved by a method according to claim 19, according to which a rolling mill according to the invention is used for the treatment of viscous masses, in particular for comminution and uniform distribution in a binder suspended solid particles, wherein the layer thickness sensor the value of the layer thickness of the treated viscous Measured mass on the roller.
• the detection of the layer thickness preferably takes place continuously.
• the layer thickness sensor provides the current and detected layer thickness of the mass of a control device or control device.
• the detected layer thickness of the product serves as an output variable during the control, while at least one of the following parameters is used as the input variable:
• the detected layer thickness of the product serves as an output variable during the control, while at least one of the following parameters is used as the input variable:
• the actual layer thickness is continuously recorded during the control, compared with a desired layer thickness as a reference variable, and depending on this comparison, the actual manipulated variable is applied to the setpoint value as changes in the at least one operating parameter as manipulated variable or manipulated variables. Adjusted layer thickness.
• the layer thickness can be controlled in the inventive method on the one hand to a maximum value of 0.1 mm and on the other hand be controlled to a minimum value of 1 micron.
• the layer thickness is controlled within a range of 1 ⁇ m to 0.1 mm. Within this layer thickness range, good dispersion results can be achieved.
• boundary conditions for the layer thickness boundary conditions for other important parameters can also be specified.
• an individual temperature window is preset for each roller (minimum and maximum temperature).
• an individual pressure window is provided for each nip (minimum and maximum contact pressure).
• the inductive sensor detects a first distance between a reference line of the layer thickness sensor device and a metallic boundary surface or metallic surface of the roller,
• the confocal and / or the capacitive sensor detects a second distance between the reference line of the layer thickness sensor device and the surface of a mass film on the roller, and
• the layer thickness of the bulk film is determined using a difference between the first distance and the second distance.
• This approach measures both the distance to the roll surface (inductive sensor) and the distance to the product surface (confocal sensor or triangulation sensor or capacitive sensor) and has the advantage that mechanical-geometrical changes can be made to the rolling mill, e.g. Changes in distance due to hermetic expansion of the rollers, vibrations of the rollers, wear of the rollers, etc., be compensated. The subtraction results in a layer thickness value which is independent of such possibly occurring changes in distance.
• the film thickness sensor device is attached to the third roll of a three-roll mill, and the product layer thickness on the third roll is measured.
• Input variable The input variable controls the output variable.
• Output variable The output variable is controlled by the input variable.
• Guide size In this case, the lead height is the target layer thickness.
• the operator can set the desired gap distance between the rolls more easily by adjusting the layer thicknesses via the layer thickness measurement.
• the operator sees the display of the actual layer thickness on the third roller and can change the actual layer thickness by manually changing the contact pressure, the roller temperatures and possibly the mechanical gap setting.

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• Engineering & Computer Science (AREA)
• Food Science & Technology (AREA)
• Manufacturing & Machinery (AREA)
• Mechanical Engineering (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Life Sciences & Earth Sciences (AREA)
• Chemical & Material Sciences (AREA)
• Polymers & Plastics (AREA)
• Crushing And Grinding (AREA)
• Battery Electrode And Active Subsutance (AREA)
• Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)

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• 2006
  • 2006-04-21 DE DE102006019214A patent/DE102006019214A1/de not_active Withdrawn
• 2007
  • 2007-03-26 KR KR1020087028496A patent/KR20090009253A/ko not_active Application Discontinuation
  • 2007-03-26 JP JP2009505695A patent/JP2009534169A/ja active Pending
  • 2007-03-26 CN CNA2007800143785A patent/CN101426582A/zh active Pending
  • 2007-03-26 WO PCT/CH2007/000161 patent/WO2007121596A2/de active Application Filing
  • 2007-03-26 EP EP07710820A patent/EP2010328A2/de not_active Withdrawn

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