Separation device and method of operation

Abstract

A device 1 serving to separate particles of a bulk material deliverable at a starting location and processable and removable at a destination location with different or similar particle sizes or at least approximately uniform particle sizes, comprises at least one separating element 3 having a metal separating plate 31 provided with a through opening 30, which separating element can be supplied with ultrasonic energy and for this purpose is connected to an ultrasonic transducer 6 and held by a holding device 2. According to the invention, the holding device 2 is a mounting shaft 2 which is held fixedly or movably, in particular rotatably and / or axially slidably, at one or both ends and which is connected at one or both ends to an ultrasonic transducer by which ultrasonic energy can be coupled via the mounting shaft 2 to the separating element 3, the separating element 3 being dimensionally stable.

Description

[Technical Field]

[0001] The present invention relates to a separation device comprising a holding device for holding a separation element, preferably a sieve, and to an operating method for this separation device. [Background technology]

[0002] In many industrial sectors, such as the food, chemical, pharmaceutical, and construction materials industries, intermediates that are available in particulate form, i.e., "atomized" in the form of particles separated from one another, are often required. In this form, the intermediates can be accurately dosed and used efficiently. Undesirable taste, solidification, and inaccurate dosing, which can cause financial or medical problems, are avoided. Bulk materials may need to be atomized in uniform particle sizes (particle size) or even in different particle sizes.

[0003] The separation device thus allows particles of the bulk material to be separated from one another and, if necessary, provides the bulk material with a substantially uniform particle size. The bulk material is transported from an input location to an output location where the bulk material is provided in the desired form. This transport is usually carried out under the influence of gravity, under the influence of mechanical movement, and in sorting techniques, and possibly under the supply of ultrasonic energy.

[0004] According to https: / / en.wikipedia.org / wiki / Sieve, in an example of a sieve device, the separation device has a sieve lining containing a number of openings the same size as the separation media. The size of the openings is called the mesh size. Larger particles remain above the openings (sieve overflow), while smaller particles pass through (sieve passage). Particles approximately the same size as the mesh size are called the limit grain. A sieve may consist of one or more stacked sieve layers, with the sieve layer with the largest mesh size located at the top of the sieve stack. The cleanliness of the screen lining is important to the performance of the screen. In particular, clogging of the sieve openings by boundary grains must be prevented by appropriate means (e.g., by brushes, balls, chains, rubber cubes "running" above or below the sieve, or, in the case of conical or double-cylindrical perforations, by increasing the hole diameter downwards).

[0005] In large-scale applications, the screen lining is excited by a drive to perform specific movements to improve sorting performance. The movements of the screen lining serve to further convey the feed material along the length of the screen, to expel boundary particles through the mesh openings, and to improve the sustainability of the separation (sorting efficiency).

[0006] Tumbler sorting machines are known (see, for example, EP 0 943 374 A2), which comprise a screen structure that can be put into a tumbler motion (throwing and swinging motion), and a support device that resiliently supports the screen structure and a mounting shaft that is driven in rotation by an electric motor, which drives a sliding pin with adjustable inclination and eccentricity, on which the screen structure is mounted. The mounting shaft and sliding pin thus set the screen lining in a predetermined, constant motion. Such systems are complex in design, cause considerable building vibration and noise, and require a relatively high level of maintenance.

[0007] The flowability of powders and bulk materials plays an important role during their transport, storage, mixing, sorting, dosing and handling. When screening bulk materials, it is important that the particles are able to separate and pass through the screen openings.

[0008] WO 2018219840A1 describes a sorting device including a support device for holding a screen, which has a screen lining held by a screen frame connected to a drive device. The drive device, controlled by a control unit, has at least three actuators, each connected to the support device via a first rotary joint on the one hand and to the screen frame via a second rotary joint on the other hand. As a result, the screen is held solely by the actuators and is movable within a range of motion and, optionally, rotatable. The screen lining is also preferably exposed to ultrasonic energy to accelerate the sorting process. This separation device, which produces very good results, is also complex and requires a relatively large amount of space. On the other hand, feeding bulk material through a transport container is not easy or can only be achieved with great effort.

[0009] JP 2011-245446 A discloses a separation device using a screen lining supported by an outer frame and abutted by a metal partition wall, through which ultrasonic energy is transmitted from an ultrasonic source to the screen lining. Under the influence of ultrasonic energy, particles of bulk material smaller in diameter than the mesh size of the screen lining can pass through the screen lining more quickly as screen passages. Particles of bulk material larger in diameter than the mesh size of the screen lining are carried outward through the outer frame as screen overflow. This separation device, including the screen lining and adjacent partition wall, is also relatively complex.

[0010] German Patent No. 4448017B4 discloses a device for separating, classifying, inspecting, filtering, or classifying dry solids or dry solids in a liquid, including a separating surface mounted within a screen frame and an associated ultrasonic transducer, which can apply vibrations to the separating surface. The ultrasonic transducer is associated with at least one resonator, which contacts the screen surface, is tuned to the resonance of the ultrasonic transducer, and can be vibrated by the ultrasonic transducer. If the screen is to be subjected to mechanical vibrations, the screen is installed, for example, in a vibration separator. Installation in a vibration separator requires correspondingly high costs. Furthermore, the mechanical action that can be exerted on the screen by the vibration separator is limited in its form and only slowly takes effect.

[0011] Dietmar Schulze, Pulver and Schuttguter, Fliesseigenschaften and Handhabung, 3rd Edition, Springer-Verlag Berlin 2014, Chapter 1, describes common problems with bulk materials. If the outlet opening is too small, a rigid dome (bridge) can form, stopping the flow of the bulk material. Another problem can be core flow, which occurs when the hopper walls are not steep or smooth enough. In this case, the bulk material in the filled silo cannot slide directly down the hopper wall. A potentially asymmetrical dead zone is formed, where the bulk material can no longer flow out by gravity alone. Core flow can also result in an extremely short residence time for part of the product, so that newly filled product cannot be immediately withdrawn again and processed and aerated intermediately within the silo. The described problems are due, on the one hand, to the equipment conditions and, on the other hand, to the properties of the bulk material (strength, friction). When designing silos, feed hoppers, bins, etc., or optimizing powders and bulk materials, the behavior of the bulk material must first be determined, which then leads to the geometry (hopper, outlet size) through the application of sound design methods.

[0012] Therefore, known devices are usually tied to the processing of a particular type of bulk material, which is why flexible use of these devices is not possible. [Prior art documents] [Patent documents]

[0013] [Patent Document 1] European Patent Application Publication No. 0943374A2 [Patent Document 2] International Publication No. 2018219840A1 [Patent Document 3] Patent Publication No. 2011-245446 [Patent Document 4] German Patent No. 4448017B4 [Patent Document 5] Chinese Patent No. 105827059A [Non-patent literature]

[0014] [Non-Patent Document 1] Dietmar Schulze, Pulver and Schuttguter, Fliesseigenschaften and Handhabung, 3.Edition, Springer-Verlag Berlin 2014, Chapter 1 Summary of the Invention

[0015] The present invention is therefore based on the object of providing an improved device for separating particles of bulk material, which enables the particles of the bulk material to be separated from one another using ultrasonic energy.

[0016] The device of the present invention allows good distribution of bulk materials on a separating element, such as a separating plate, to be achieved more quickly and by simple means.

[0017] It may be possible to provide the particles of the bulk material in different particle sizes or similar particle sizes, or at least in a roughly uniform particle size.

[0018] Furthermore, methods of operation of this improved separation device will be identified that advantageously allow for a variety of processes to be carried out, such as processes for loading, separating, mixing, aerating, degassing, and unloading bulk materials. Additionally, processes for cleaning and maintenance of the separation device will be advantageously feasible.

[0019] The separation device will have a simple and compact design and will be easy to maintain. The separation device will have high efficiency and a correspondingly reduced energy consumption rate. Vibrations and shocks, such as those caused by known separation devices, will be avoided or significantly reduced without reducing the efficiency of the separation device.

[0020] To avoid bulky installations, it may be possible to process bulk materials within the shortest possible path length between input and output locations.

[0021] The processed bulk material will be provided in high quality with a high degree of separation so that inaccurate dosing during application of the processed bulk material can be avoided.

[0022] During the processing of the bulk material, further processing may be easily performed. In particular, removal of the bulk material in a specific processing state may be easily performed. Furthermore, advantageously, at least one additional material may be mixed with the bulk material, after which the mixed product may also be provided in the desired particle shape.

[0023] Processing of bulk materials may advantageously be possible under increased or decreased pressure of air or liquid.

[0024] The separation device and the supply and / or discharge channels may be designed almost independently of the type of bulk material and may be realized with small dimensions. Residues of the bulk material and corresponding changes in the cross section of the transport path, in particular dead corners, may be avoided during operation of the separation device.

[0025] The operating method will allow the setting of optimal operating parameters of the separation device so that the present bulk material currently being processed can be optimally separated.

[0026] This problem is solved by a separation device and an operating method, respectively, having the features specified in claims 1 and 14. Advantageous embodiments of the invention are specified in the further claims.

[0027] The device, which functions to separate particles of bulk material that can be delivered at an input location and processed and removed at an output location in different particle sizes or at least approximately a single particle size, has at least one separation element having a metal separation plate with a through opening, which separation element can be supplied with ultrasonic energy and for this purpose is connected to an ultrasonic transducer and held by a holding device.

[0028] According to the invention, the holding device is a mounting shaft, which is held fixedly or movably, in particular rotatably and / or axially displaceably, at one or both ends, and which is connected at one or both ends to an ultrasonic transducer by means of which ultrasonic energy can be coupled via the mounting shaft to the separation element, the separation element being designed to be dimensionally stable.

[0029] For the transmission of electrical energy, in particular of AC voltage from the ultrasonic generator to the ultrasonic transducer, the mounting shaft is preferably provided with a contact device, preferably comprising a slip ring and sliding contacts connected thereto, via which AC and / or DC voltage signals, possibly control signals, can be transmitted to the ultrasonic transducer or to a control device provided thereon and / or to the ultrasonic transducer connected to the mounting shaft, which supplies the ultrasonic transducer.

[0030] The ultrasonic transducer preferably includes a piezoelectric transducer, which preferably includes several piezoelectric elements. The piezoelectric elements are preferably sandwiched between two metal plates, which are securely or insecurely connected or welded to the mounting shaft and connected together or individually to the ultrasonic generator by connection contacts. Vibrations of the piezoelectric elements are transmitted to the mounting shaft via the metal plates and further to at least one separating element. The metal plates may be arranged as screw nuts on the threads of the mounting shaft. Tightening the nuts fixes the piezoelectric elements and simultaneously provides an optimal connection between the nuts and the mounting shaft. It may also be advantageous to use only one screw nut that can press the piezoelectric elements against the metal plates that are securely connected to the mounting shaft.

[0031] The mounting shaft may be made of one or more parts and may be integrally connected to the motor shaft of the drive motor or connected by a coupling.

[0032] In a preferred embodiment, the piezoelectric elements are ring-shaped so that they can surround the mounting shaft. This design provides a compact structure with maximum efficiency. Preferably, there are 5 to 20 piezoelectric elements. The piezoelectric elements are preferably separated from each other by contact elements and, if necessary, by insulating plates.

[0033] The piezoelectric element can be excited to vibrate by an alternating voltage in the ultrasonic range, and the vibrations are transmitted to at least one separation element. The ultrasonic vibrations isolate particles of the bulk material from each other and, if they have a correspondingly small diameter, allow them to pass through the separation element. Furthermore, strong contact between the separation element and the bulk material is prevented. Thus, static and / or sliding friction, and therefore the frictional forces occurring between the separation element and the bulk material, are substantially reduced, so that the bulk material remains flowing and unimpeded.

[0034] The separation element of the present invention can process any type of bulk material, homogeneous or heterogeneous, and bulk material with any particle size. Within the separation device, the bulk material can be subjected to processes in which it is thermally treated and / or aerated and / or purified and / or its composition is modified.

[0035] The separator plate may have a lattice or wire mesh structure connected to the mounting shaft by at least one mounting element such as a connecting sleeve or by at least two connecting rods with the same or different diameters. The separator plate may, for example, be surrounded by a ring, which is connected by connecting rods to the mounting shaft or to a mounting sleeve surrounding the mounting shaft.

[0036] By using a dimensionally stable separation element and connecting the separation element to an elongated mounting shaft, e.g., rod-shaped or cylindrical, made of metal, to which ultrasonic energy can be coupled, a separation device is obtained that has many advantages.

[0037] Since the separation elements are preferably held by a centrally located mounting shaft and are dimensionally stable, larger mounting devices, in particular the separation elements including the mounting frame, are no longer required. At the same time, the bulk material can be acted upon more directly and flexibly. The bulk material can optionally be subjected to any mechanical and acoustic influences to optimize the separation process. The separation process can also be performed more efficiently with reduced energy consumption. Via the mounting shaft, at least one separation element or at least one separation plate can be subjected to any axial and rotational movement, as well as any ultrasonic waves. If the bearing device holding the mounting shaft is also rotatably mounted, additional rotational movements can be performed.

[0038] Since the at least one separation element is held centrally by the mounting shaft rather than peripherally, the separation device becomes more flexible. By avoiding connecting elements that peripherally connect the separation element with, for example, a housing, a holder, or a further mounting element, parts that are now independent of the separation element can be realized with a higher degree of freedom.

[0039] Due to the enhanced flexibility of the device, the characteristics of the separation device can be largely determined by the operating parameters of the control device, and therefore the design of the separation device requires less care and effort. The separation plate can, for example, protrude circumferentially between the flanges to form a closure for, for example, a housing and ensure that bulk material can only pass through the separation element. Essentially, the mounting of the mounting shaft can also be supported or replaced by the mounting of the separation element.

[0040] The separation device can be adapted to the bulk material and the goals specified by the user by simple means or by selecting operating parameters. Thus, the separation device of the present invention can optimally process various types of bulk material. For example, chemical powders, food particles, crystals, small mechanical parts, etc. can be processed using the same separation device. On the other hand, if the same bulk material is always processed, it is desirable to provide the separation device with correspondingly adapted dimensions.

[0041] Thus, the dimensions of the separation device and separation elements may vary by several orders of magnitude.Similarly, the operating parameters, in particular the rotational speed and switching frequency of rotatably mounted separation elements, may vary by several orders of magnitude.

[0042] The separation device can be designed almost independently of the bulk material type, with the possibility of setting substantially different operating parameters, including the supply and / or discharge channels. This allows the effort required to manufacture the separation device to be advantageously shifted from the design level to the software level. The separation device has a simple yet highly flexible design, which allows the realization of novel processes for the processing of bulk materials.

[0043] Bulk materials can be processed within short path lengths between input and output locations, so that separation devices according to the invention intended for the processing of bulk materials in the mentioned industrial sectors can generally be realized with limited dimensions.

[0044] Due to the advantageous possibility of acting on the bulk material, particle separation can be performed more efficiently not only in the area of ​​the separation element, but also along the entire bulk material transport path. Due to the enhanced flexibility of the separation device and its more advantageous effect on the bulk material, changes in the cross section of the transport path, particularly residues with dead corners, are advantageously avoided. Therefore, optimal operation of the separation device can be maintained for a longer period of time, and the effort required for maintenance of the separation device is significantly reduced. The increased flexibility of the separation device also allows for at least partial self-cleaning of the device. For this purpose, the separation device can be moved at the required speed, for example, to remove screen overflow. In a preferred embodiment, a cleaning agent can be injected or sprayed through the same channel to influence the work process (see FIG. 4a).

[0045] The enhanced flexibility of the separation device therefore allows not only optimal realization of the separation process, but also the realization of further processes, in particular mixing and washing processes. During the processing of the bulk material, for example, additional materials, substances and media can be easily added at any time or in any separation element, and / or intermediate processed bulk material can be removed.

[0046] Bulk materials can also be processed in a closed chamber under any gas pressure, even under vacuum if necessary.

[0047] Due to the advantageous direct action on the bulk material, energy requirements can be reduced. Vibrations and shocks, such as those caused by known separation devices, are significantly reduced. Due to the reduced energy, the bulk material can be acted on more directly and therefore more intensively. Vibrations of the separation device, which can lead to vibrations of the building, are advantageously avoided.

[0048] The processed bulk material can be provided in high quality with a high degree of separation, so that inaccurate dosing during application of the processed bulk material is avoided. As mentioned, qualitative changes in the bulk material can be advantageously made during the work process. Miscellaneous materials are integrated into the bulk material in an optimally dispersed form.

[0049] The separating element or separating plate preferably forms a rotational body.

[0050] In a preferred embodiment, the separator plate has a basic structure and is, for example, flat, conical, helical, spiral, corrugated, wavy, sawtooth, or is provided with steps or bends. In a particularly preferred embodiment, the separator plate is spherically wavy. With this design, ultrasound can be propagated particularly advantageously across the surface of the separator plate.

[0051] At least one of the separator plates may also have an additional three-dimensional surface structure that is superimposed on the base structure and that can engage with and displace the bulk material. Preferably, the surface structure is used in the form of radially inclined depressions or protrusions that are arranged at regular or irregular intervals. Thus, the separator plate may have a first base structure that favors uniform propagation of ultrasound waves, which may be covered by a surface structure that aids in mechanical interaction with the bulk material.

[0052] The separator plate may have a uniform thickness or may taper gradually or continuously from the center to the periphery, for example in the form of a blade. At the thinner periphery, oscillations with a larger amplitude may develop. Otherwise, the dimensions of the separator plate are selected according to the required strength of the bulk material and the diameter of the separator plate. At the point where the separator plate connects to the mounting shaft, the thickness of the material may be in the range of 1 mm to 50 mm. If the separator plate tapers outward, the thickness of the material may be reduced by a factor of 10 to 100. The diameter of the separator plate may be in the range of 10 mm to 100 mm or even more. Again, the properties of the bulk material, especially its specific gravity, are decisive.

[0053] Preferably, separator plates made of ultrasonically conductive metals such as aluminum, steel, especially stainless steel, copper, brass, titanium, or alloys containing such metals are used. It is also advantageous to use separator plates provided with a resistive protective layer, such as a noble metal layer.

[0054] The separator plates are manufactured, for example, by basic forming from granular, powdered or liquefied material, by forming such as rolling, forging, bending, compression molding or deep drawing, by hot erosion such as spark erosion, die-sinking EDM or laser cutting, or by machining, for example by turning, drilling, milling or grinding.

[0055] The through-openings in the separator plates can also be realized by the mentioned processes. The diameter of the through-openings is, for example, in the range of 1 micron to 1000 microns for powdery bulk materials. For bulk materials containing larger mechanical particles, the diameter of the through-openings can be, for example, in the range of 1 mm to 15 mm. The diameter of the through-openings of all separator elements can be the same or can gradually change, so that the first separator plate to pass has the largest through-opening and the last separator plate to pass has the smallest through-opening.

[0056] In a preferred embodiment, the separation element has a central axis and is rotationally symmetrical about this central axis. The mounting shaft is preferably coaxial or only slightly eccentric with respect to the central axis of the separation element. If the mounting shaft is eccentric with respect to the central axis, oscillations and vibrations are obtained that promote the separation process. The separation plates are preferably rotatably or displaceably arranged so that they can be rotated or displaced from a coaxial position to an eccentric position and fixed. It is particularly advantageous that at least one separation element in this arrangement can be selectively rotated in one direction or the other at a desired switching frequency, and preferably selectively accelerated.

[0057] The separation element can be connected to the mounting shaft in various ways. For example, the separation plate has a mounting element in the form of a connecting sleeve or at least two connecting rods, preferably with different diameters. For example, four connecting rods with different diameters are provided crosswise. By using such connecting rods, the coupling can be carried out in an advantageous manner, in particular in a circularly rotating manner. Standing waves are avoided or reduced. Instead, various waves are superimposed, thereby activating the entire surface of the separation plate.

[0058] The one-piece or assembled mounting shaft, made of metal, is elongated and preferably rod-shaped or cylindrical. Preferably, the mounting shaft has several interconnectable shaft elements, each of which is fixably, rotatably, and optionally detachably connected to an associated separation element. Preferably, the individual shaft elements are securely connectable to one another, threaded together, or welded together. If the individual shaft elements are detachable from one another, the separation device can be configured as desired and adapted to the specific bulk material.

[0059] In a particularly preferred embodiment, the one-piece or assembled mounting shaft is connected at one or both ends to a drive motor by which the mounting shaft or shaft elements can be driven individually in one direction or in the other, or alternately in one and the other, about their longitudinal axes.

[0060] The mounting shaft is fixedly or rotatably mounted at one or both ends in a bearing device and is preferably connected to the mounting body, and optionally to a transport container, by means of radially aligned connections.

[0061] For the realization of various working processes, the mounting shaft comprising at least one separation element is preferably arranged in a transport vessel in which the bulk material is captured, in which various conditions such as gas overpressure or gas underpressure or vacuum, spray mist, etc. can be realized, and therefore various treatment processes can be realized.

[0062] For this purpose, the transfer vessel is provided with an open or optionally closable through-channel through which the bulk material can be conveyed from an input location to an output location.

[0063] The transfer vessel preferably has an outlet opening for at least one of the separation elements through which bulk material components, such as processed or separated bulk material components, or overflow can be discharged. Preferably, the outlet opening can optionally be closed.

[0064] In a further preferred embodiment, the transport container preferably comprises an inlet channel and / or an outlet channel for each of the separation elements, which are realized for example by tubular elements.

[0065] In a preferred embodiment, a power supply device connected to the drive motor and optionally to one or more ultrasonic transducers, and a control unit containing a control program, are provided, which can control the process for separating particles from the bulk material and, optionally, further processes, such as cleaning or maintenance processes. By setting parameters, various process phases can be realized. In the mixing phase, the bulk material can be roughly dispersed by continuous or alternating rotation of at least one separating element over several or fractional rotations, e.g., 45° to 180°. In the working phase, the bulk material can be subjected to mechanical vibrations by alternating rotation of at least one separating element over only a small rotation, e.g., 0.5° to 5°, which separates the particles from each other and allows them to pass through the through-openings of the separating element. In the discharge phase, the remaining bulk material or screen overflow can be thrown outward and removed by rotating at least one separating element at high speed.

[0066] The parameters can be varied over a wide range and independently of the ultrasonic energy coupled into the separation element.

[0067] The rotation speed can range from one revolution to several thousand revolutions and depends primarily on the particle size, shape, and specific gravity of the bulk material and the design of the separation element. The magnitude of acceleration is also important. High accelerations over a fraction of a revolution, for example in the range of 5° to 180°, displace and mix the layers of the bulk material during the mixing phase. This effect can be enhanced by incorporating surface structures into the separation plate.

[0068] During the working phase, the bulk material is already relatively well mixed and at least partially separated on the separating element. This phase involves complete separation of the bulk material particles and transport through the through-holes of the separating element. For this purpose, the mounting shaft is moved back and forth over a small rotational range, for example, within a range of 0.5° to 5°, with a switching frequency preferably within a range of 10 Hz to 1000 Hz or higher. Thus, during the working phase, the separator is exposed to mechanical vibrations within a range of 10 Hz to 1000 Hz and ultrasonic vibrations, typically within a range of 10 kHz to 40 kHz. The switching frequency for the mechanical vibrations is preferably changed continuously or abruptly during the working phase. The frequency of the ultrasonic vibrations is also preferably changed continuously or abruptly. For example, the frequency of the switching frequency and the frequency of the ultrasonic vibrations are key-shifted, i.e., continuously changed between several, possibly predetermined or randomly selected, frequency values. Alternatively, the frequency of the switching frequency and the frequency of the ultrasonic oscillations are continuously changed or each is subjected to a so-called scan, whereby the frequency changes proceed in opposite or in the same direction as each other. It is also possible for one of the frequencies to be rescanned while the other one is scanned.

[0069] Sporadic changes from the working phase to the mixing phase are also possible.

[0070] In the evacuation phase, the separation elements are freed of bulk material at high speeds, for example, in the range of 25 to 1000 revolutions per second. A cleaning liquid is then preferably introduced, for example, by spraying, into the separation device to clean the separation elements. Finally, a gaseous medium, such as air, can be introduced to dry the separation device. Thus, after the evacuation phase, the separation device can be transferred by the operating software to a cleaning phase, in which the separation device is returned to its initial state. Therefore, the separation device can be operated with minimal maintenance, especially with regard to this self-cleaning function.

[0071] In a preferred embodiment, alternating forces or vibrations can be coaxially coupled to the mounting shaft during the mixing and / or working and / or discharging phases, so that forces can also act on the bulk material particles parallel or antiparallel to gravity. Such force effects with selectable frequencies can be coupled to the mounting shaft in a simple manner, for example according to the plunger coil principle of an acoustic loudspeaker. For example, the mounting shaft can comprise at its bottom or top a cylindrical magnet that is held elastically or vertically displaceable and is embedded in a coil to which an alternating current, for example in the range of 5 Hz to 15 kHz, is supplied. All of the above effects on the mounting shaft can occur simultaneously, alternately, or only sporadically.

[0072] The ultrasonic generator is preferably designed to output an AC voltage signal at a frequency within the range of 15 kHz to 45 kHz. The ultrasonic generator is preferably designed to continuously change the frequency of the AC voltage signal and / or shift the frequency of the AC voltage signal and / or change the amplitude of the AC voltage signal. The frequency of the output signal within the aforementioned frequency range is preferably changed with a resampling frequency within the range of 10 Hz to 2 kHz. For example, the output signal of the ultrasonic generator is repeatedly shifted between ultrasonic frequencies of 25 kHz and 35 kHz 10 times per second with a shift keying frequency of 10 Hz. The repetition frequency can also be used to scan through a sequence of ultrasonic frequencies, e.g., 25 kHz, 30 kHz, and 35 kHz. Instead of regular resampling, continuous frequency change may be performed. For example, scanning between two or more ultrasonic frequencies is performed 10 times per second with a change frequency of 10 Hz.

[0073] The described change in ultrasonic frequency ensures that no stationary wave nodes occur at the separator plate and that the effect of the ultrasonic signal occurs without spacing.

[0074] The present invention will now be described in more detail with reference to the drawings. [Brief explanation of the drawings]

[0075] [Figure 1a] 1 is a diagram of a separation device 1 of the present invention including an optional drive device 8, 80 in a basic embodiment including only one separation element 3, in which the separation element 3 has a cone-shaped separation plate 31 including a through opening 30, and in which the separation element 3 is held by a fixedly or rotatably mounted mounting shaft 2, and in which an ultrasonic transducer 6 supplied by an ultrasonic generator 70 is connected to the mounting shaft 2. [Figure 1b] 1b is a diagram of the separation device 1 of FIG. 1a including an exemplary device for supplying ultrasonic energy to the rotatably mounted separation element 3. FIG. [Figure 2] FIG. 1 is a view of a separation device 1 of the present invention in a quarter section, comprising three separation elements 3A, 3B, 3C, which are held by a fixedly or rotatably mounted multi-piece mounting shaft 2, and an ultrasonic transducer 6 is connected to the multi-piece mounting shaft 2. [Figure 3] 1 is a diagram of a separation device 1 of the present invention comprising six separation elements 3A, 3B, 3C, 3D, 3E, 3F arranged within a transport container 5, the separation elements being rotatably held by a multi-part mounting shaft 2 to which ultrasonic energy can be coupled. [Figure 4a] 1 is a diagram of a separation device 1 of the present invention, comprising six separation elements 3A, 3B, ... rotatably supported by a mounting shaft 2, which further allows for the supply of material or gas to the treated bulk material and the removal of the treated bulk material at different times. [Figure 4b] FIG. 4b is a view of a portion of the separation device 1 of FIG. 4a. [Figure 5a]1 is a diagram of a separation device 1 of the present invention comprising helical separation elements 3A, . . . , 3L, which are rotatably mounted by associated mounting shafts 2 to which ultrasonic energy can be applied. [Figure 5b] FIG. 5b is a view of a portion of the separation device 1 of FIG. 5a. [Figure 6] 2a in a preferred design of the separation element 3, which comprises four connecting rods 321, 322, 323, 324 of different thicknesses connecting the metal plate 31 to the mounting shaft 2. FIG. [Figure 7] FIG. 5 is a diagram of a separation element 3 including a separation plate 31 in the shape of a spherical wave as used in the device of FIG. [Figure 8] 1 is a diagram of a separation element 3 having a lattice structure or wire mesh 319 surrounded by a ring 320 connected by connecting rods 321, 322, 323, 324 to a mounting shaft 2 or to a mounting element 32 surrounding the mounting shaft 2. DETAILED DESCRIPTION OF THE INVENTION

[0076] FIG. 1 shows a device 1 according to the invention for separating particles of a process or bulk material S, which can be supplied at an input location A and, after processing in the separation device 1, removed at an output location B with different or similar particle sizes, or at least with approximately uniform particle sizes.

[0077] In this embodiment, the separation device 1 has only one separation element 3 comprising a metal separation plate 31, which forms a body of revolution or a cone and preferably has through openings 30 of the same size. The separation element 3 or conical separation plate 31 has a central mounting element 32, which is held fixedly or rotatably and / or axially displaceably by a mounting shaft 2. The mounting shaft 2 is aligned with its longitudinal axis x, which is coaxial with the axis of rotation of the separation element 3, preferably parallel to the axis of gravity. The bulk material is therefore conveyed through the separation device 1, preferably by gravity.

[0078] This conveying process is preferably assisted and accelerated by the following means: During the treatment, the separating element 3 is at least intermittently exposed to ultrasonic waves, typically in the frequency range of 15 kHz to 40 kHz. For this purpose, the mounting shaft 2 is connected at its underside to an ultrasonic transducer 6, to which an electrical signal 71A from an ultrasonic generator 70 can be sent. The ultrasonic generator 70 is preferably controllable by a control device 9 or a control program 99 implemented in the control device 9, so that the ultrasonic frequency can be set and changed as desired.

[0079] Furthermore, the separating element 3 may be subjected to mechanical vibrations in the frequency range of a few Hz to, for example, 1 kHz. As a first option, a drive motor 8 is provided which is able to rotate the mounting shaft 2 in one direction and / or in the other. The range of rotation, the acceleration and rotation speed as well as the switching frequency for changing the direction of rotation are again controllable by the control device 9 or a control program 99 implemented in the control device 9. High-frequency vibration motors which may be used in a separating device according to the invention are known, for example from Chinese patent no. 105827059A.

[0080] The separation device 1 may further be subjected to vibrational motions including force effects along the longitudinal axis x of the mounting shaft 2. Such vibrations may be easily generated by a motor, the motor shaft of which is subjected to an eccentric load. The mounting shaft 2 may be coupled to such a motor 80, which may be controllable by a control device 9 or a control program 99 implemented in the control device 9. Any frequency of vibration may then be set according to the speed of the motor 80.

[0081] Alternatively, the mounting shaft 2 may be connected to a magnet 28, preferably cylindrical, which is arranged in a coil 88, which may be supplied with an alternating current by a frequency generator 800. The switching and disconnection of the alternating current and the frequency can be controlled by a control device 9 or a control program 99 implemented in the control device 9.

[0082] In a preferred embodiment, the control of the separation device 1 in the mixing phase and / or the working phase and / or the discharge phase is performed taking into account the sensor signal emitted by the sensor 95. For example, the bulk material located on the separation element 3 is monitored optically.

[0083] The described options for vertical or rotational vibration and for coupling ultrasonic energy from the separation element 3 can be used individually or possibly in combination. The vibration frequencies and / or vibration amplitudes can be the same or different.

[0084] The mounting shaft 2, which serves as a holding device for the separation element 3, is held by the mounting device 52 and the bearing device 58 either fixedly or rotatably and / or axially displaceable to the extent required by the amplitude during axial displacement or vibration. In this embodiment, the mounting shaft 2 is held on one side only. Furthermore, the ultrasonic transducer is attached to the underside of the mounting shaft 2, preferably in a form-fitting and force-fitting manner, preferably threaded, clamped, for example by press-fitting, or welded.

[0085] FIG. 1B shows the separation device 1 of FIG. 1A, including an exemplary device for supplying ultrasonic energy to the rotatably mounted separation element 3. Electrical energy is supplied to the ultrasonic transducer 6 from an ultrasonic generator 70 via a multi-core cable 71B and a contact device 4. The contact device 4 has sliding contacts 41, 43 that abut against current collector rings 42, 44 rotatably mounted on a mounting shaft 2. The multi-core cable 71B is connected to the sliding contacts 41, 43. An AC voltage in the ultrasonic frequency range is transmitted via the sliding contact 41. The corresponding slip ring 42 is connected to a connecting cable 77, via which the AC voltage is transmitted to the piezo element 631 or, optionally, to a control unit 60, where it is sent to the piezo element 631 via a switch.

[0086] The ultrasonic transducer 6 preferably comprises several piezo elements 631 separated from one another by contact elements 64 (only one is shown), each of the piezo elements 631 having a transmission opening through which the mounting shaft 2 is guided. The piezo elements 631 are pressed together by two locking elements 632 connected to the mounting shaft 2, via which the ultrasonic vibrations are transmitted to the mounting shaft 2. The locking elements 632 are, for example, screw nuts, each of which is rotatably held by a thread machined in the mounting shaft 2. The piezo elements 631 can therefore be fixed in a simple manner and supplied with a voltage via the intermediate contact elements 64.

[0087] In a preferred embodiment, a control unit 60 connected to the central control device 9 is arranged in the ultrasonic transducer 6. A control signal is transmitted via a cable 71B to a further sliding contact 43 connected to a further current collecting ring 44. The control signal is transmitted via a control line 78 to the control unit 60, which subsequently controls the output of an AC voltage to the piezo element 631 and to the terminal contact 64, respectively. The control unit 60 can also have an ultrasonic generator to which a supply voltage can be fed via the contact device 4, which ultrasonic generator is provided for outputting an ultrasonic signal. In this case, the illustrated ultrasonic generator 70 is integrated into the control unit 60.

[0088] 1a and 1b show a great advantage of the separation device 1 according to the invention. It can be seen that with minimal constructional effort the mounting shaft 2 can be used to act in various ways on the separation elements 3 mechanically and / or with ultrasonic energy. Mechanical and acoustic vibrations, rotations and axial displacements can be transmitted to the mounting shaft 2 by simple means, and the mounting shaft 2 can be mounted in a simple way so that it can be rotated and / or displaced. The mechanical movements and / or ultrasonic waves acting on the mounting shaft 2 can be transmitted centrally from the mounting shaft 2 to the at least one separation element 3.

[0089] It is also particularly advantageous that the separation device of FIGS. 1a and 1b shown in a simple embodiment can be constructed in a simple manner.

[0090] FIG. 2 shows a separation device 1 according to the present invention, including a mounting shaft 2. This mounting shaft 2 has three shaft elements 2A, 2B, and 2C, each of which is connected to a separation element 3A, 3B, or 3C. The shaft elements 2A, 2B, and 2C have connecting elements 21 and 22 on both sides, which can be inserted into each other or screwed together. Thus, the mounting shaft 2 can be extended as desired to result in a separation device 1 including a desired number of separation elements 3A, 3B, and 3C. The shaft elements 2A, 2B, and 2C are preferably of identical design, but may differ in their dimensions, particularly their lengths, so as to be able to hold, for example, separation elements 3 of different sizes. An ultrasonic transducer 6 is securely connected, and optionally screwed, to the lowest shaft element 2C. Thus, the mounting shafts 2 of all separation devices 1 according to the present invention may be of a single design or may consist of several shaft elements.

[0091] The separation elements 3A, 3B, 3C have openings of various sizes so that individual particles can be separated not only from one another but also by size, or can be grouped on each of the separation elements 3A, 3B, 3C. After the working phase, the particles of bulk material are separated from one another by various sizes and are ready to be removed on the separation elements 3A, 3B, 3C. In the discharge phase, the separation elements 3A, 3B, 3C can be rotated to guide the separated bulk material particles away through the outlet channels 5A, 5B, and 5C by centrifugal force.

[0092] The individual separating elements 3A, 3B, 3C have through openings 30 of different sizes. This is typically provided when particles of different sizes are to be separated from one another. However, through openings 30 of different sizes can also be provided when chunks of bulk material are crushed in the upper separating elements 3A, 3B and only at the end individual particles of the same size are separated from one another.

[0093] 3 shows a separation device 1 according to the invention, comprising six separation elements 3A, ..., 3F arranged in a transport container 5. The separation elements 3A, ..., 3F are held by a multi-part mounting shaft 2, which is aligned with its longitudinal axis x parallel to the conveying axis of the separation device 1. In this preferred embodiment, the mounting shaft 2 comprises a lower shaft element 2A and an upper shaft element 2B, which are coaxially aligned with one another and rotatably connected to one another at opposite ends by coupling elements 26, optionally coupling sleeves, and which are rotatably mounted at their opposite ends in bearing devices 58A, 58B. Ultrasonic transducers 6A, 6B held by the shaft elements 2A, 2B are integrated into the bearing devices 58A, 58B. Downstream of the bearing devices 58A, 58B, contact devices 4A, 4B, which are connected to at least one ultrasonic generator 70, are connected to the shaft elements 2A, 2B, and the contact devices 4A, 4B are further connected to associated drive motors 8A and 8B, respectively, via associated couplings 85A and 85B, respectively.

[0094] Thus, the lower three separation elements 3A, 3B, 3C can be rotated by a lower drive motor 8A controlled by the control program 99, while the upper three separation elements 3D, 3E, 3F can be rotated by an upper drive motor 8B controlled by the control program 99.

[0095] Similarly, control signals and AC voltage signals can be transmitted to the lower and upper ultrasonic transducers 6A, 6B separately via the lower and upper contact devices 4A and 4B, respectively.

[0096] The shown separation device 1 therefore has two smaller separation devices 1', 1" comprising three separation elements 3A, 3B, 3C and 3D, 3E, 3F, respectively. The lower separation device 1' comprising the three separation elements 3A, 3B, 3C and the upper separation device 1" comprising the three separation elements 3D, 3E, 3F can be operated independently in the same or different processing phases. During a first processing phase, a working phase program can be applied to the upper separation device 1" while a mixing phase program is applied to the lower separation device 1'. In a second processing phase, a working phase program can be applied to the lower and upper separation devices 1', 1". In a third processing phase, a discharge phase program can be applied to the upper separation device 1" while the lower separation device 1' is still operated in the working phase.

[0097] The mounting shaft 2 containing the six separation elements 3A, ..., 3F is arranged in a transfer vessel 5 which is open at the top and bottom and has a conveying channel 50 through which the bulk material S is conveyed by gravity. The transfer vessel 5 further has outlet openings or outlet channels 50A, ..., 50F in its side walls, through each of which the overflow or intermediate products Sa, Sb, Sc, Sd, Se, Sf of the bulk material S can be conveyed outwards and away from the associated separation element 3A, ..., 3F, as symbolically shown. During the discharge phase, the rotational speed of the separation elements 3A, ..., 3F is increased so that the intermediate products Sa, Sb, Sc, Sd, Se, Sf are carried away by centrifugal force.

[0098] The power supply device 90 shown is controlled by the control unit 9 to supply power to the motors 8A, 8B and possibly to the ultrasonic generator 70, which may also be integrated into the power supply device 90.

[0099] FIG. 4a shows a separation device 1 of the present invention, which includes six separation elements 3A, ..., 3F rotatably held by a mounting shaft 2 and having a flat spherical wave shape. The spherical wave shape is the wave shape that occurs in water after a stone is thrown into it. The spherical wave shape promotes optimal distribution of ultrasound waves so that the separation of bulk materials is particularly efficient. The distribution elements 3A, 3B, ... preferably have one or more resonant frequencies at which maximum vibrations are generated with minimum ultrasonic energy. Particularly during the working phase, the frequency of the ultrasound waves is preferably scanned between the resonant frequencies to produce the most intensive and changing impact on the bulk material, rapidly separating it into its particles.

[0100] The separation elements 3A, ..., 3F are connected to one another by a mounting shaft 2, which may be formed integrally or may comprise several shaft elements rigidly connected to one another. The mounting shaft 2 is connected to an upper drive motor 8B via a coupling 85B, which can receive a control signal 81B from a control unit 9 or a power supply device 90 connected thereto. The mounting shaft 2 is rotatably supported in an upper bearing device 58 and is effectively suspended by the upper ultrasonic transducer 6b. The transport container 5 is fixed to the floor, wall, or ceiling of a building, for example by a bracket.

[0101] At the bottom of the separation device 1, below the lowest separation element 3F, there is provided a closing cone 55 in which the last processed particles of bulk material are collected.

[0102] The transfer vessel 5 has tubular inlet channels 500A, ..., 500F and outlet channels 501A, ..., 501F for each of the separation elements 3A, ..., 3F. Through the inlet channels 500A, ..., 500F, preferably at least one powdered solid material, at least one liquid, or at least one gaseous medium can be supplied to the bulk material. Through the output channels 501A, ..., 501F, material can be removed from the individual separation elements 3A, ..., 3F or from the end cones 55.

[0103] The transfer vessel 5 in this configuration is preferably sealed so that processing of the bulk material can take place under positive or negative pressure. Bulk material or bulk material components can be supplied through inlet pipes 5S1, 5S2. Processed bulk material can be removed through one or two outlet pipes 5X, 5Y.

[0104] The shown embodiment of the separation device 1 therefore makes it possible to carry out various intermediate treatments of the bulk material and to aerate or degas the bulk material in a simple manner.

[0105] At the height of each separating element 3A, . . . , 3F, any mixing process can be carried out in order to obtain a particular mixed product or to accelerate the separating process at that height.

[0106] Figure 4b shows an enlarged view of a portion of the separation device 1 of Figure 4a. The output channels 501A, ..., 501F are cut at an angle at the front, like the input channels 500A, ..., 500F. Advantageously, other shapes, such as side-directed blade shapes, may also be used, in which case the material can be easily collected and transported away, and optionally sucked out.

[0107] 5a shows a separation device 1 according to the invention, comprising spiral-shaped separation elements 3A, ..., 3L, which are rotatably mounted by associated shafts 2 and to which ultrasonic energy can be applied. The separation elements 3A, ..., 3L are oriented in pairs and vertically offset from one another. Arrangements in which the separation elements 3A, ..., 3L extend continuously in the same direction in the shape of a spiral or vortex are also possible.

[0108] This separation device 1 allows all particles of the bulk material to pass through the entire transfer vessel 5 and be completely separated from one another. This separation device 1 is preferably used when particles of the bulk material are to be separated from one another but not grouped by size.

[0109] Figure 5b shows an enlarged view of a portion of the separation device 1 of Figure 5a.

[0110] FIG. 6 shows the separation device of FIG. 2a in a preferred configuration, including four connecting rods 321, 322, 323, 324 of different diameters, by means of which the metal plate 31 is connected to the mounting shaft 2. The diameters of the connecting rods 321, 322, 323, 324 are varied according to an arithmetic or geometric progression. In this way, the coupling of ultrasonic energy can be advantageously influenced. Specifically, a wave image can be generated in which the wave nodes are reduced. Symbolically, surface structures in the form of radial waves are indicated by dashes, and these surface structures are used to interact with the bulk material to displace and disperse it.

[0111] Figure 7 shows a separation element 3 as used in the device of Figure 4. The separation element 3 or separation plate 31 has a spherical wave shape.

[0112] 8 shows a separation element 3 comprising a separation plate 31 having a lattice structure or wire mesh 319 surrounded by a ring 320, which is connected to the mounting shaft 2 or to the mounting shaft 32 surrounding the mounting shaft 2 by connecting rods 321, 322, 323, 324. This separation element 3 can also be used in all devices 1 according to the invention. The separation plate 31 can be conical, as in FIG. 6, or flat or corrugated, as in FIG. 7.

[0113] It is essential that the separating element 3 is dimensionally stable so that its functionality is maintained under load and the bulk material is safely held.

Claims

1. A device (1) for separating particles of a bulk material deliverable to an input location and processable and removable at an output location into different particle sizes or at least approximately a single particle size, the device (1) comprising at least one separating element (3) having a metallic separating plate (31) with a through opening (30), said separating element (3) being capable of being supplied with ultrasonic energy and for this purpose being connected to an ultrasonic transducer (6) and held by a holding device (2), 1. The device (1), characterized in that the holding device (2) is a mounting shaft (2) which is movably held at one or both ends and connected at one or both ends to the ultrasonic transducer (6), ultrasonic energy can be coupled by the ultrasonic transducer (6) to the separation element (3) via the mounting shaft (2), the separation element (3) is dimensionally stable, the mounting shaft (2) is rotatably held, or the mounting shaft (2) is displaceable along its longitudinal axis, or the mounting shaft (2) is rotatably held and displaceable along its longitudinal axis, the mounting shaft (2) comprises a contact device (4) having a current collecting ring (42; 44) and a sliding contact (41; 43), and via the contact device (4) an AC or DC voltage signal can be transmitted to the ultrasonic transducer (6).

2. 2. A separation device (1) as claimed in claim 1, characterized in that the separation plate (31) has a flat or curved surface, or that the separation plate (31) has a constant thickness or a thickness that decreases outward, or that the separation plate (31) has a flat or curved surface and a constant thickness or a thickness that decreases outward.

3. 3. A separation device (1) according to claim 1 or 2, characterized in that the separation plate (31) has a lattice or wire mesh structure (319) which is connected to the mounting shaft (2) by at least one mounting element (32, 320), such as a connecting sleeve (32) or by at least two connecting rods (321, 322) having the same or different diameters.

4. 4. The separation device (1) according to claim 1, characterized in that the at least one separation element (3) has a central axis (x) and is rotationally symmetrical with respect to said central axis (x), and the mounting shaft (2) is aligned at least approximately coaxially with said central axis (x).

5. 5. A separation device (1) according to claim 1, characterized in that the separation plate (31) of the at least one separation element (3) has a basic structure, such as a conical, wave or spherical wave, helical or vortex shape, and optionally a surface structure superimposed on the basic structure, the surface structure being provided for mechanical interaction with the bulk material.

6. A separation device (1) according to any one of claims 1 to 5, characterized in that the separation plate (31) is connected to the mounting shaft (2) by at least one mounting element (32), such as a connecting sleeve or by at least two connecting rods (321, 322) having the same or different diameters.

7. 7. The separation device (1) according to claim 6, characterized in that the mounting shaft (2) has a plurality of shaft elements (2A, 2B, 2B), each shaft element (2A, 2B, 2B) being fixedly or removably connected to one of the plurality of separation elements (3A, 3B, 3B), and the shaft elements (2A, 2B, 2B) are preferably securely connected to one another, rotatably connected to one another, screwed to one another or welded to one another.

8. 8. A separating device (1) according to any one of claims 1 to 7, characterized in that the mounting shaft (2) is connected at one end or at both ends to a drive motor (8A; 8B) by means of which the mounting shaft (2) or the two shaft elements (2A, 2B) of the mounting shaft (2) can be driven individually in one direction or the other direction around their longitudinal axis or alternately in one direction and the other direction.

9. A separation device (1) as described in any one of claims 1 to 8, characterized in that the ultrasonic transducer (6) preferably has a piezoelectric transducer (61) with at least one piezoelectric element (611), and an alternating voltage signal of constant or variable frequency, preferably within a frequency range of 20 kHz to 45 kHz, can be supplied to the piezoelectric transducer (61) from an ultrasonic generator (70).

10. 10. The separation device (1) according to claim 9, characterized in that a plurality of piezoelectric elements (631), preferably ring-shaped, are clamped between two metal elements or metal plates (632), which are connected to the mounting shaft (2) in a form-fitting, screwable, pressure-fit or integral manner and to the ultrasonic generator (70) by means of connection contacts (64) and the contact device (4).

11. 11. The separation device (1) according to any one of claims 1 to 10, characterized in that the mounting shaft (2) to which the at least one separation element (3) is connected is arranged in a transport container (5) having an open or closable through channel (50) through which the bulk material can be transported from the input position to the output position.

12. 12. A separation device (1) according to claim 11, characterized in that the transport container (5) has an outlet opening (50A, 50B, 50C) for at least one of the separation elements (3A, 3B, 3C) and / or that the transport container (5) has an inlet channel (500A, 500B, 500C) and / or an outlet channel (501A, 501B, 501C), preferably for each of the separation elements (3A, 3B, 3C).

13. 9. A separation device (1) according to claim 8, characterized in that it is provided with a power supply device (90) connected to the drive motor (8A) or to the drive motors (8A, 8B) and a control unit (9) containing a control program by means of which the process for separating the particles of the bulk material is controllable.

14. 9. An operating method for controlling a separation device (1) according to claim 8, comprising: In a mixing phase, the drive motor (8A) or drive motors (8A, 8B) are controllable such that the mounting shaft (2) is rotated in one direction and again in the other direction at a predefined mixing speed by a rotational portion corresponding to a switching frequency, or During the discharge phase, the mounting shaft (2) is rotated in one direction or the other for a number of revolutions at a given discharge speed; 13. A method for controlling a separation device (1), characterized in that the predetermined mixing speed and the switching frequency are selected such that the bulk material is mixed and the predetermined discharge speed is selected such that remaining bulk material is removed from the at least one separation element (3) by centrifugal force.

15. 15. The operating method for controlling a separation device (1) according to claim 14, characterized in that during the mixing phase bulk material is removed from at least one of the separation elements (3) or auxiliary material is added to at least one of the separation elements (3) during the mixing phase.

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