Ultrasonic cleaning of stirring chamber for agricultural sample slurries

Abstract

A system for treating agricultural slurry is disclosed. The system includes a stirring device (500) having a stirring chamber (502) and one or more outlet ports (520) for releasing slurry from the internal cavity. The stirring device (500) also includes a filter (522) fluidly coupled to the one or more outlet ports (520) and positioned within the interior cavity of the stirring chamber (502) to filter the slurry. An ultrasonic transducer (560) is positioned proximate to or in physical contact with the filter (522) to clean the filter.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to U.S. Provisional Application No. 63 / 586656, filed September 29, 2023; U.S. Provisional Application No. 63 / 586672, filed September 29, 2023; and U.S. Provisional Application No. 63 / 586702, filed September 29, 2023, all of which are incorporated herein by reference in their entirety. Technical Field

[0003] This disclosure generally relates to agricultural sampling and analysis, and more specifically to ultrasonic cleaning of mixing chambers for mixing agricultural material samples (e.g., soil). Background Technology

[0004] Regular soil testing is an important aspect of agricultural technology. Test results provide valuable information about the soil's chemical composition, such as the levels of plant-available nutrients and other important properties (e.g., nitrogen, magnesium, phosphorus, potassium, pH, etc.), enabling the addition of various soil amendments to maximize the quality and quantity of crop production.

[0005] In some sampling and chemical analysis processes, raw or bulk agricultural material samples, such as soil (or other agricultural materials), extracted from the field may be prepared for analysis. The equipment used to prepare the soil for analysis may need to be cleaned between uses. Summary of the Invention

[0006] This disclosure provides systems, apparatus, and methods for cleaning mixing chambers for mixing agricultural materials. In one embodiment, a system for processing agricultural slurry is disclosed, the system comprising: an agricultural sample slurry source; a mixing device including: a mixing chamber comprising: a housing defining an internal cavity configured to receive the agricultural sample slurry; one or more outlet ports configured to release slurry from the internal cavity; a filter fluidly coupled to the one or more outlet ports and positioned within the internal cavity of the mixing chamber to filter the slurry; and an ultrasonic transducer positioned proximate to or in physical contact with the filter.

[0007] In another aspect, an ultrasonic transducer for causing the formation of cavitation bubbles in a liquid is disclosed, the ultrasonic transducer comprising: a front drive element; a rear drive element; two piezoelectric elements positioned between the front drive element and the rear drive element; a bolt configured to pass through at least a portion of the front drive element, the rear drive element, and each of the two piezoelectric elements; and an insulating sleeve surrounding a portion of the bolt to prevent the bolt from contacting the two piezoelectric elements, the insulating sleeve comprising a dielectric material; wherein the ultrasonic transducer vibrates along a first axis; wherein the front drive element has a front portion near the front end of the ultrasonic transducer and an opposing rear portion; and wherein the cross-sectional area of ​​the front portion of the front drive element is smaller than the cross-sectional area of ​​the rear portion of the front drive element, wherein each cross-sectional area is perpendicular to the first axis.

[0008] In another aspect, a method for cleaning a filter of a stirring device for agricultural sample slurry is disclosed, the method comprising: positioning an ultrasonic transducer close to or in physical contact with a filter of the stirring device; stirring the agricultural sample slurry in the stirring device, the stirring device including a filter; and activating the ultrasonic transducer to clean the filter.

[0009] Although, for ease of description, the mixing chamber apparatus, system, and related methods or processes for preparing agricultural sample slurries may be described herein with reference to soil samples, this represents only a single category of application for the disclosed embodiments of the invention. Therefore, it should be understood that the same apparatus and related methods or processes can be used to process any type of sample, not limited to agricultural samples. These samples may include any liquid, including liquid solutions and suspensions. The disclosure herein should therefore be broadly interpreted as an apparatus and related method or process for analyzing samples, regardless of the material type or collection method. Attached Figure Description

[0010] This disclosure will be more fully understood through detailed description and accompanying drawings, wherein similar elements are indicated by similar reference numerals, and wherein:

[0011] Figure 1 This is a schematic diagram of an example system used for analyzing agricultural samples;

[0012] Figure 2 It is possible to do so Figure 1 A perspective view of the stirring chamber used in an example system for analyzing agricultural samples;

[0013] Figure 3 It is a section taken along line 3-3. Figure 2 A cross-sectional view of the stirring chamber;

[0014] Figure 4 It is a section taken along line 4-4. Figure 3 A cross-sectional view of the stirring chamber;

[0015] Figure 5 It is a section taken along line 5-5. Figure 2 A cross-sectional view of the stirring chamber;

[0016] Figure 6 It is a section taken along line 6-6. Figure 2 A cross-sectional view of the stirring chamber;

[0017] Figure 7 It is possible Figure 1 A schematic diagram of an alternative embodiment of the stirring chamber used in the system;

[0018] Figure 8 This is a flowchart illustrating the method used to analyze the sample;

[0019] Figure 9 This is a schematic system block diagram of an alternative system for processing and analyzing agricultural samples;

[0020] Figure 10 yes Figure 9 A first top perspective view of the mixing device of the system, which includes a mixing chamber for processing and analyzing agricultural sample slurry;

[0021] Figure 11 This is its second top-down perspective view;

[0022] Figure 12 This is its first upward perspective view;

[0023] Figure 13 This is its second perspective view from below;

[0024] Figure 14 This is its first side view;

[0025] Figure 15 This is its second side view;

[0026] Figure 16 This is its third side view;

[0027] Figure 17 This is its fourth side view;

[0028] Figure 18 This is its top view;

[0029] Figure 19 It is its bottom view;

[0030] Figure 20 This is its first longitudinal sectional view;

[0031] Figure 21 It comes from Figure 20 Magnified details;

[0032] Figure 22 yes Figure 10 A second longitudinal sectional view of the stirring device;

[0033] Figure 23 It comes from Figure 22 Magnified details;

[0034] Figure 24 This is a cross-sectional view of the stirring chamber of the stirring device;

[0035] Figure 25 This is a perspective view of an ultrasonic transducer positioned near a filter in a mixing chamber, according to one embodiment.

[0036] Figure 26 It is a section taken from line 26-26. Figure 25 A cross-sectional view of an ultrasonic transducer, wherein the ultrasonic transducer is mounted to the housing of the stirring chamber;

[0037] Figure 27 This is its front view;

[0038] Figure 28 It is separate from the stirring chamber. Figure 25 A three-dimensional view of an ultrasonic transducer;

[0039] Figure 29 yes Figure 25 An exploded view of an ultrasonic transducer, without its housing;

[0040] Figure 30 This is a perspective view of an ultrasonic transducer positioned close to the stirring chamber according to the second embodiment;

[0041] Figure 31 It is a section taken along line 31-31. Figure 30 A cross-sectional view of an ultrasonic transducer, wherein the ultrasonic transducer is mounted to the housing of the stirring chamber;

[0042] Figure 32 This is its front view;

[0043] Figure 33 It is separate from the stirring chamber. Figure 30 A three-dimensional diagram of an ultrasonic transducer; and

[0044] Figure 34 yes Figure 30 An exploded view of an ultrasonic transducer, without its housing.

[0045] Figure 35 This is a flowchart of a method for cleaning a filter of a stirring device for agricultural sample slurry, according to one embodiment.

[0046] All accompanying drawings are schematic and not necessarily drawn to scale. Unless otherwise expressly stated, components that are numbered and appear in one drawing but not in other drawings are the same components. Unless otherwise expressly stated, any drawing referred to in this document with an integer number, where that integer number may appear in multiple drawings with the same integer prefix but different letter suffixes, shall be interpreted as referring to all of those drawings. Detailed Implementation

[0047] The features and advantages of this disclosure are illustrated and described herein with reference to exemplary ("Example") embodiments. The description of these exemplary embodiments should be read in conjunction with the accompanying drawings, which should be considered an integral part of the entire written description. Therefore, the disclosure is not limited to these exemplary embodiments, which illustrate certain possible non-limiting combinations of features that may exist alone or in other combinations of features.

[0048] In the description of the embodiments of the invention disclosed herein, any references to direction or orientation are intended for convenience of description only and are not intended to limit the scope of this disclosure in any way. Relative terms such as “lower,” “upper,” “horizontal,” “vertical,” “above,” “below,” “up,” “top,” “bottom,” and their derivatives (such as “horizontally,” “downward,” “upward,” etc.) should be understood to refer to the orientation described at the time or shown in the drawings under discussion. These relative terms are for convenience of description only and do not require the device to be constructed or operated in a particular orientation. Terms such as “attach,” “join,” “connect,” “link,” “interconnect,” etc., refer to a relationship in which structures are directly or indirectly fixed or attached to each other through an intermediate structure, and to movable or rigid attachments or relationships, unless otherwise expressly stated.

[0049] Throughout this document, any scope disclosed herein is a simplified expression describing each value within that scope. Any value within the scope may be chosen as an endpoint value. Furthermore, all references to prior patents or patent applications cited herein are incorporated herein in their entirety. In the event of any conflict between the limitations in this disclosure and the limitations in the cited references, this disclosure shall prevail.

[0050] Figure 1A schematic diagram of a system 100 for analyzing agricultural samples is shown. System 100 includes a grinder 110, a mixing chamber 200, a pump 120, a filter 130, and an analysis unit 140. The grinder 110 receives an agricultural sample (e.g., soil) and grinds it to ensure that the maximum particle size of the agricultural sample is below the maximum particle size required for subsequent analysis by the analysis unit 140. For example, clods of soil and plant material can be ground to reduce their size, making them suitable for passage through the system. Additionally, water can be added from a fluid source to promote efficient grinding and provide a liquid slurry that facilitates the passage of the sample through the system and ultimately for final analysis by the analysis unit 140.

[0051] The sample (i.e., slurry) is then transferred from the grinder 110 to the mixing chamber 200. The purpose of the mixing chamber 200 is to ensure that the agricultural sample is homogeneous. This can be done by a variety of methods, including mixing, stirring, shaking, vibrating, or any other means suitable for ensuring thorough mixing of the sample. Additionally, measurements can be performed on the sample to verify that adequate mixing has occurred. For example, the liquid level, density, or mass of the sample within the mixing chamber 200 can be measured to determine adequate sample size and homogeneity. Again, water can be added from a fluid source to achieve the target density, improve homogeneity, or for other purposes. The fluid source can be recycled from water used elsewhere in the process or new water can be added. Furthermore, the sample can be returned from downstream components to the mixing chamber for additional processing, as discussed in more detail below.

[0052] The sample is transferred from the mixing chamber 200 to the pump 120. The pump 120 pressurizes the sample to ensure it is effectively filtered by the filter 130. In other embodiments, the pump 120 may be located downstream of the filter 130, such that the filter 130 is on the suction side of the pump 120. The pump 120 and filter 130 may be used to remove unwanted large components from the sample (e.g., gravel that has passed through a grinder). The pump 120 and filter 130 may also be used to recirculate a portion of the sample along with additional water from a water source, allowing the sample slurry to undergo additional processing and conditioning within the mixing chamber 200. This may be because only a portion of the sample is needed for further testing. The sample density, water / solid ratio, and homogeneity may also be iteratively adjusted to facilitate further analysis.

[0053] Once the sample has passed through filter 130, analysis unit 140 performs further analysis on some or all of the sample. This analysis may include measurements of physical properties such as density or mass. The analysis may also include a series of chemical analyses. The sample can then be discarded. Additional water from one or more fluid sources can be used to flush the system and ensure accurate measurements of future samples.

[0054] The controller 300 controls all functions of the stirring chamber 300. The controller 300 includes a memory 310, a processor 320, and a device interface 330. The controller 300 can be a central controller for controlling the functions of all components of the system. In other embodiments 300, the controller 300 may be integrated into a single component (e.g., the stirring chamber 200). In this embodiment, an additional controller 300 may be integrated into other components and can communicate via a bus or other communication system. Alternatively, the controller 300 may be integrated into a single component and may also be connected to other components in the system. It can be seen that the arrangement of the controller 300 can be distributed or centralized, depending on the desired configuration.

[0055] Turning Figure 2-6 An exemplary embodiment of a stirring chamber 200 is shown. The stirring chamber has a housing 220 formed by a gear head 221, an upper housing 222, a middle housing 223, and a lower housing 224. The gear head 221 receives a motor 225 and is coupled to the upper housing 222. The upper housing 222, the middle housing 223, and the lower housing 224 together form an internal cavity 230. The internal cavity 230 extends along a longitudinal axis AA and is elongated along the longitudinal axis AA. The internal cavity 230 extends along the longitudinal axis AA from a top end 231 to a bottom end 232.

[0056] Multiple ports 240 are formed in the housing 220 and fluidly coupled to the internal cavity 230. The ports 240 can perform various functions, including receiving samples, outputting samples, allowing sensors to measure samples, allowing the injection of fluid (e.g., water) from a fluid source, or any other desired function. Optionally, some ports 240 can be blocked and used for optional functions not implemented in every system.

[0057] The mixing chamber 200 is also incorporated with a stirrer 250. The stirrer 250 collectively includes a motor 225, a gear train 251, and two stirrer shafts 252. In other embodiments, only one stirrer shaft may be used. Each illustrated stirrer shaft 252 includes blades 253 that agitate the sample when the stirrer shaft 252 rotates. The gear train 251 connects the motor 225 to the stirrer shaft 252. Optionally, more than one motor 225 may be used and the gear train 251 may be omitted. Optionally, one or more stirrer shafts 252 may be used. In other configurations, the gear train 251 may be configured as belt or chain driven instead of gear driven, but may still be referred to as gear train 251. The gear train 251 may reduce or increase the speed of the stirrer shaft 252 relative to the motor 225, or the gear train 251 may not reduce or multiply the speed of the motor 225.

[0058] The signal from sensor 210 is received by controller 300. The signal from sensor 210 can be in the form of analog voltage or current, or it can be a digital signal. The signal from sensor 210 corresponds to a parameter measured by the corresponding sensor 210. The signal can vary over time and can represent a parameter such as pressure or some other parameter that changes continuously based on the measurement conditions at the corresponding sensing port.

[0059] Next, the internal cavity 230 is filled with a fluid of unknown density (e.g., an agricultural sample). Again, both locations must be covered by the sample fluid. The pressure difference between these two locations is measured again to determine the sample differential pressure. The density can be calculated using the following formula: Sample density = Reference density * Sample differential pressure / Reference differential pressure. For example, if the reference density is arbitrarily assigned a value of 1, the sample density can be determined by referring to the reference density. A sample with a density twice that of the reference fluid will have a sample density of 2, while a sample with a density half that of the reference fluid will have a sample density of 0.5. Alternatively, density can be defined in any accepted unit system. For example, density can be defined in grams per cubic centimeter, kilograms per cubic meter, pounds per cubic foot, or any other recognized unit system.

[0060] In the absence of a reference fluid of known density, the internal volumes and positions of sensing ports 241, 242, and 243 can be used to calculate the expected pressure difference between the two ports for a given reference fluid. This can then be used to calculate a theoretical reference differential pressure, which can be used to calculate the sample density using the same equations as when using an actual reference fluid. However, this is subject to some potential loss of accuracy due to variations in the internal volume of the internal cavity 230, variations in the position of the sensor 210, and other variables.

[0061] Furthermore, methods for determining the mass of a sample can be performed. If the geometry and volume of the internal cavity 230 are known, the mass of the liquid in the region between the two measurement points can be determined. For example, in a cylindrical volume, the mass of the internal cavity 230 in the region between the two measurement points can be determined by multiplying the sample density by the volume of the region between the two measurement points.

[0062] In another method, sensor 210 can be used to determine the liquid level of the sample within internal cavity 230. The presence or absence of the sample at each location can be determined by comparing the pressure measured by each sensor 210 with atmospheric pressure. Alternatively, the liquid level between sensors 210 can be calculated by combining density measurements with pressure measurements. For example, if sensor 210 at first sensing port 241 measures a pressure equal to atmospheric pressure, the sample must have a liquid level below the position of first sensing port 241 relative to the longitudinal axis AA. If sensor 210 at first sensing port 241 measures a pressure greater than atmospheric pressure, the sample must have a liquid level above the position of first sensing port 241. Combining pressure and density information, the liquid level between ports 240 can be extrapolated. If additional sensing accuracy is required, additional sensing ports can be added, or additional sensors 210 of different types can be used.

[0063] In another method, information about the density in a region of the internal cavity 230 can be used to measure the homogeneity of the sample. In the case that the sample is a non-uniform liquid (i.e., a dilute suspension or other liquid with non-uniform density), measurements at three or more points will provide information about the distribution of the sample's density in three or more regions.

[0064] For example, in this system, the density of the sample can be measured in a first region R1 between the sensor 210 located at the first sensing port 241 and the sensor 210 located at the second sensing port 242. The density can also be measured in a second region R2 between the sensor 210 located at the second sensing port 242 and the sensor 210 located at the third sensing port 243. Finally, the density can be measured in a third region R3 between the sensor 210 located at the first sensing port 241 and the sensor 210 located at the third sensing port 243. Therefore, the density can be measured for the first region, the second regions R1 and R2, and the third region R3, which overlaps with both the first and second regions R1 and R2. Adding an additional sensor 210 at the additional sensing ports allows for measurements in additional regions, further increasing information about the homogeneity of the sample.

[0065] As can be seen, each of the first, second, and third regions R1, R2, R3 may have a different density. The density differences between the first, second, and third regions R1, R2, R3 allow for quantitative analysis of the homogeneity of the sample within the internal cavity 230. In some embodiments, the stirrer 250 may be activated in response to detecting a density difference between two regions exceeding a predetermined threshold.

[0066] In other embodiments, if the density of the sample in the first region R1 is greater than the density in any of the second or third regions R2, R3, the speed of the stirrer shaft 252 may be reduced, or by extension, the speed of the motor 225 may be reduced, to allow particles or other components of the sample to settle to the bottom end 232 of the internal cavity 230. If the density of the sample in the first region R1 is less than the density in any of the second or third regions R2, R3, the speed of the stirrer shaft 252 may be increased, or by extension, the speed of the motor 225 may be increased, to increase agitation and move particles from the second region R2 to the first region R1.

[0067] In each case, the speed of the stirrer shaft 252 can be controlled using proportional control, or enabled based on a series of predetermined thresholds, each corresponding to a density difference. In other embodiments, the speed can be controlled using any known method designed to improve sample homogeneity. Any number of regions can be created as needed by any number of sensors 210.

[0068] In other embodiments, sensor 210 need not be as... Figure 2-6 As shown in the embodiment, it is located in the sensing port. In other embodiments, for example... Figure 7 As schematically illustrated, sensor 210 can measure pressure at different locations using tubes or probes. Each tube of sensor 210 terminates at a different position relative to the longitudinal axis AA to allow measurements at different heights, which is consistent with... Figure 2-6 The embodiments are the same. In other words, the tube of each sensor 210 terminates at a first sensing port, a second sensing port, or a third sensing port 241, 242, 243. The particle distribution within the sample is shown to have a different distribution relative to the position along the longitudinal axis AA.

[0069] The use of a stirrer 250 is optional. In some embodiments, the stirrer 250 may be omitted, and density or fluid level measurements can be performed without the use of the stirrer 250. In other embodiments, the sample need not have suspended solids, but can be any fluid, whether homogeneous or heterogeneous.

[0070] In summary, the method for analyzing sample 400 begins at step 410, providing a chamber 200 having an internal cavity 230. The internal cavity 230 extends along a longitudinal axis from a bottom end 232 to a top end 231. In step 420, a first sensor 210 is fluidly coupled to the internal cavity 230 at a first position relative to the longitudinal axis AA. A second sensor 210 is fluidly coupled to the internal cavity 230 at a second position relative to the longitudinal axis AA. Optionally, a third sensor 210 is fluidly coupled to the internal cavity 230 at a third position relative to the longitudinal axis AA. Each of the first, second, and third positions is different and may be spaced apart from each other along the longitudinal axis AA.

[0071] Subsequently, in step 430, a sample is added to the internal cavity 230. In step 440, the controller 300 reads multiple signals from sensor 210. In step 450, the sample density or fluid level is determined via the multiple signals from sensor 210. Optionally, sensor 210 may be a pressure sensor 210. Optionally, more than one density may be determined for different regions located between any two sensors, as described above. In a further optional configuration, stirrer 250 may be operable to increase or decrease stirring in response to the measured density in one or more different regions.

[0072] Alternative slurry density measurement systems and related methods

[0073] Figure 9-24 An alternative embodiment of the slurry density measurement system is shown. The system generally includes a stirring device 500, which is generally similar to the stirring device described herein, having a stirring chamber 200 and an agitator 250 operable to stir the slurry. For the sake of brevity, the details are not repeated in their entirety here, but reference is made to the previous description. The following description of this stirring device will focus on the differences between the two related designs.

[0074] Compared to the mixing chamber 200 of a previous mixing device, the mixing chamber 502 of this mixing device 500 is partially configured differently to determine the density of the agricultural sample slurry in a different manner without using the pressure sensing port 240 and associated pressure sensing equipment. Instead, this mixing device includes a mechanically isolated mixing chamber 502 configured to receive the agricultural sample slurry from the grinder 110 and gently agitate the slurry to keep most of the agricultural solids (i.e., particles) suspended in order to obtain slurry density and other related measurements. In a non-limiting embodiment, the sample slurry may be a soil slurry.

[0075] The mechanically isolated mixing chamber 502 is formed by a section of the mixing device housing, which is mechanically isolated from other parts of the mixing device and associated accessories (e.g., slurry inlets and outlets) that engage with the mixing chamber. Therefore, the weight of the mixing chamber is independently supported by a load cell, completely independent of the other parts of the mixing device and associated systems. In one embodiment, this load cell is not limited to a strain gauge 504, which is rigidly mounted to an available support structure. As further described herein, this allows for accurate measurement of the weight of the mixing chamber 502 both empty and filled with slurry; the difference represents the weight of the volume of slurry in the chamber. This information is used in conjunction with other measurements described below to determine the overall density of the slurry and the water / solids ratio of the slurry.

[0076] Current overall reference Figure 9-24 The mixing device 500 generally includes a partially hollow housing 510 that is elongated vertically, which may include an upper housing section 511 and a lower housing section 512. The upper housing section 511 mounts and supports a mixing mechanism, which includes a stirrer 250 driven by a motor 225 and a gear train 251, as described above. However, in this embodiment, the stirrer may consist of only a single rotatable stirrer shaft 252 and blade 253 assembly, which is supported from above by the upper housing section 511 in a suspended manner, as shown. Notably, in alternative embodiments, if necessary, depending on the nature of the slurry, two shaft and blade assemblies may be used to adequately mix the slurry while keeping the solids suspended. The stirrer shaft is supported by the upper housing section of the mixing device independently of the mixing chamber. In some embodiments, the stirrer shaft 252 and blade 253 may be directly driven by a motor, thus omitting the gear train.

[0077] Although the disclosed mixing mode uses a single agitator shaft and blade assembly suspended downward from the upper housing section 511 into the mixing chamber 502, other mixing modes may be used in other embodiments, including, but not limited to, pneumatic mixing (air bubbles blown upward into the internal cavity 530 of the mixing chamber through the slurry) and recirculating the sample slurry via a separate pumping slurry flow loop.

[0078] The lower housing section 512 defines an agitation chamber 502, which includes an internal cavity 530 configured to receive a volume of coarse slurry (or filtrate) received from the grinder 110. An agitator shaft 252 and blade 253 assembly is positioned within the internal cavity 530 but is not supported in any way by the lower housing section 512. The upper housing section 511 provides sole support for the agitator shaft and blade assembly, which enters the internal cavity of the agitation chamber through an open top portion 531. The agitation chamber 502 also includes a slurry inlet port 540 near the top portion of the internal cavity 530 and a waste port 543 located at the bottom or floor 530a of the internal cavity 530.

[0079] It is noteworthy that, in one embodiment, the mixing chamber 502 defined by the lower housing section 512 may be mechanically isolated from the upper housing section 511 via an isolation air gap 506 formed between them. An annular isolation air gap 508 may also be provided to mechanically isolate the slurry inlet conduit 541 (e.g., a section of pipe or tube) from the slurry inlet port 540 of the mixing chamber. This prevents any support of the mixing chamber through the slurry inlet conduit. The inlet conduit may be constructed rigidly, and otherwise may adversely affect the accurate measurement of the mixing chamber weight obtained by the strain gauge 504. As shown, a sliding joint may be used for the slurry inlet connection, which incorporates the annular isolation air gap 508. The slurry inlet conduit is supported independently of the mixing chamber 502 via a separate mounting bracket 541a attached to a usable support structure.

[0080] The lower housing section 512 includes a support bracket 505 configured to cantilever-fixedly connect the lower housing section (i.e., the stirring chamber) to one end 504a of the strain gauge 504, as shown. The support bracket 505 can be mounted to a lateral side of the lower housing section. The opposite end 504b of the strain gauge is fixedly connected to a available support structure, which in one embodiment may be provided by a portion of a bracket 507 rigidly connected to the upper housing section 511. Other available support structures may be used to connect the end 504b of the strain gauge 504 not connected to the upper housing section thereto. The strain gauge 504 may have a horizontally elongated structure as shown in one embodiment. Mechanical fasteners, such as threaded fasteners in a non-limiting embodiment, may be used to connect the strain gauge to the bracket 507 and the lower housing section 512 (i.e., the stirring chamber). Other types of fasteners, such as rivets, clamps, etc., may also be used. Other types of load sensors may be used that are operable to measure the weight (mass) of the mixing chamber and can structurally support the mixing chamber independently of the upper housing section of the mixing device in a manner described herein.

[0081] It is worth noting that strain gauge readings are sensitive to forces and vibrations originating outside the sample slurry mixing chamber 502. Such interference is prevented or minimized by mechanically isolating the mixing chamber 502 from the rest of the mixing apparatus via the aforementioned isolation air gap 506. Furthermore, any wiring, fluid lines (pipes, tubing, etc.) or other accessories that must still be connected to the sample chamber are preferably stress-relieved locally (i.e., self-supporting and not dependent on the mixing chamber support), so that they cannot support or “push” or “pull” the mixing chamber system in any way that might adversely affect the accurate slurry weight / mass measurement results of the strain gauge 504. An example of this is the slurry inlet mounting bracket 541a described earlier. These external support measures for the mixing chamber help ensure the accuracy of the strain gauge weight / mass measurement results.

[0082] A load cell (e.g., strain gauge 504) is used to measure the weight (mass) of the slurry within the mixing chamber by determining the weight difference between the empty mixing chamber and the mixing chamber subsequently filled with slurry; this difference represents the weight of the slurry itself. To determine the density of the slurry, its volume must also be determined (density is a measurement of the mass of material per unit volume). In one embodiment, a level sensor 515 may be provided to determine the volume of slurry in the mixing chamber 502.

[0083] In one embodiment, the level sensor 515 may be a non-contact level sensor, such as an ultrasonic transducer or the like; however, other types of level sensors, including contact level sensors, may also be used if appropriate. The sensor 515 may be mounted to the upper housing section 511 and has a direct line of sight through the open top portion of the chamber to the internal cavity 530 of the mixing chamber 502 for detecting the surface level of the slurry, which is correlated via the controller 300 with the height of the slurry column in the mixing chamber. Because the dimensions of the internal cavity 530 of the mixing chamber are precisely known, the volume of slurry contained in the internal cavity of the mixing chamber at any given time can be easily determined based on the height of the present slurry column. This information may be pre-programmed into the controller 300 for determining the slurry volume based on the slurry level detection result (slurry column height).

[0084] The accuracy and repeatability of volume measurements obtained via the level sensor 515 depend on the cleanliness of the sensor. Therefore, in one embodiment, the sensor is preferably mounted in the upper housing section 511 of the stirring device 500, as far away as possible from the surface of the liquid slurry in the stirring chamber 502, to avoid splashing when the slurry is stirred. In one embodiment, a downwardly opening sensor cavity 515a recessed into the bottom of the upper housing section 511 may be provided to maximize the distance between the sensor and the surface level of the sample slurry.

[0085] The density of the slurry can be determined by dividing the total mass (weight) of the slurry measured via strain gauge 504 by the slurry volume determined via level sensor 515. In one embodiment, the density can be determined by... Figure 9 The modified system block diagram shows that the programmable controller 300 automatically calculates the density of the slurry. The strain gauge 504 and the level sensor 515 are operatively and communicatively coupled to the controller 300, which is programmed with appropriate program instructions (e.g., control logic) to calculate the density of the slurry based on the measured weight (mass) and the slurry volume calculated from the slurry level measurement.

[0086] In one embodiment, a method for automatically determining the density of an agricultural sample slurry via a controller 300 may include the following steps performed by the controller.

[0087] First, at any point before the sample slurry processing run begins, when no slurry is present in the chamber, the controller 300 measures the weight of the empty mixing chamber 502. This provides the initial weight of the empty mixing chamber. Next, a certain amount (volume) of slurry is added to the mixing chamber (e.g., the inner cavity 530) from the grinder 110 via the slurry inlet port 540, such as... Figure 9 As shown. This can be accomplished by the controller opening the isolation valve 525 (or manually) in the fluid line (indicated by the solid flow arrow) between the grinder 110 and the mixing chamber 502. The valve 525 is then closed to fluidly isolate the grinder from the mixing chamber and the controller 300. The controller measures the weight of the mixing chamber 502 with the slurry filled in the inner cavity 530. This provides a second weight measurement of the filled mixing chamber. The slurry can be agitated by the agitator 250 before or after the measurement, but agitation is preferably not performed during the slurry weight and level measurement.

[0088] Next, the controller calculates / determines the actual weight of the slurry by comparing and subtracting the weight of the empty mixing chamber from the weight of the filled mixing chamber. This represents the mass of the slurry present in the mixing chamber. It is worth noting that the mass of the slurry added to the mixing chamber 502 may not be initially known. The weight of the slurry is determined by the controller 300 based on the actual volume of slurry present in the mixing chamber 502.

[0089] The controller 300 also automatically determines the volume of the sample slurry present in the mixing chamber 502 via a level sensor 515, either before, after, or simultaneously with the step of determining the mass (weight) of the slurry. The level sensor 515 is activated by the controller to measure the level of the slurry in the mixing chamber 502.

[0090] The controller 300 is pre-programmed with data relating to the volume of slurry present in the internal cavity 530 of the mixing chamber, which is a function of the slurry column height as represented by the slurry level measurement, for example via a lookup table or appropriate equation. The controller executes a preset program to easily correlate the real-time measured slurry level (by detecting the top surface of the slurry) with the corresponding representative slurry volume presented based on the detected slurry column height. Within the capabilities of those skilled in the art, appropriate data and software instructions can be programmed into the controller to establish a correlation between the measured slurry surface level and volume.

[0091] Finally, having determined both the slurry mass and volume parameters, the controller 300 calculates the overall density of the slurry based on the slurry weight / mass and slurry level measurements obtained from the strain gauge, as well as the level of the entire slurry sample in the mixing chamber 502. This recognizes that the slurry is not an ideally homogeneous mixture, meaning that measuring the entire slurry sample averages out regions of lower or higher density within the slurry mass. Notably, it is preferable to perform the slurry weight and level measurements when the stirrer 250 is not operating, so that the slurry is in a static and stable state. This is desirable to ensure the accuracy of the slurry level detection and weight / mass measurement. Forces applied by the stirrer, slurry agitation, and the stirrer itself can all alter these measurements, making them inaccurate.

[0092] According to another aspect, the stirring device 500 also includes a spectrometer 550 to determine the water / solid ratio of the agricultural sample slurry. The spectrometer 550 is operatively coupled to a programmable controller 300, such as... Figure 9 As shown. The spectrometer can be mounted close to the bottom end of the stirring chamber 502, and in a non-limiting embodiment, as shown, it can be mounted on the lower side of the chamber to maximize the spectrometer's exposure to water-heavier particles in the sample slurry, which tend to settle to the bottom of the chamber. The spectrometer 550 includes a lens 551 that is fluid-sealed to the stirring chamber 502 to provide the spectrometer with an upward line of sight to the inner cavity 530 of the stirring chamber.

[0093] Spectrometer 550 is configured and operable to measure the reflectance of a sample slurry in a stirred chamber. More specifically, spectrometer 550 is operable in one aspect to measure the particle density (g / mL) of solids in the slurry. Based on the reflectance measurement of the sample solids in stirred chamber 502, the physical properties of the sample material, including the density of solids (particles) suspended in the sample slurry, can be determined. Knowing the density of water (≈0.998 mL / g) and the measured density of suspended solid particles (e.g., soil or others), controller 300 can be programmed to automatically calculate the water / solid ratio. Soil particle density can be predicted experimentally and correlated with the sample reflectance measurement, which is within the capabilities of those skilled in the art. This information can form the basis for the programmable controller 300 to automatically establish a correlation between reflectance and particle density.

[0094] Therefore, using the particle density of the slurry sample obtained from several reflectance measurements by spectrometer 550 and the density of the sample slurry determined by controller 300, controller 300 can further determine the actual current ratio (e.g., water / solid) of the water mass to the sample solid (particle) mass in the sample slurry based on the reflectance readings. Based on the real-time or actual current ratio, controller 300 will automatically adjust the sample slurry in stirring chamber 502 as needed until it reaches the chemical / characteristic analysis unit 140 for the system (see, for example...). Figure 9 The desired target water / solid ratio is optimized for analysis of the samples. This includes adding more water to dilute the slurry or adding more slurry to increase the amount of suspended solids in the slurry. The solids can be soil used for soil samples or any other agricultural or farm-related solids to be analyzed by the system.

[0095] A non-limiting embodiment of the process implemented by controller 300 to achieve a desired target water / solid ratio (i.e., mass ratio) based on reflectance measurements collected by spectrometer 550 may include, but is not limited to, the following control steps: Step (1): Determine the real-time or actual current water / solid ratio based on the reflectance measurements of the sample recorded by spectrometer 550. Step (2): Compare the actual water / solid ratio with a pre-programmed target water / solid ratio of the sample slurry. Step (3): Adjust the actual water / solid ratio to meet the target water / solid ratio. For example, if the actual water / solid ratio is less than the target water / solid ratio, controller 300 adds water to mixing chamber 502 (via slurry inlet port 540, a separate water inlet port, or a slurry recirculation inlet port) and repeats steps (1) and (2) once or more until controller 300 determines that the target water / solid ratio in the sample slurry is met. For example, if the actual current water / solid ratio is less than the target ratio (i.e., more dilution water is needed in the slurry), controller will initiate the process of adding water to mixing chamber 502. Conversely, if the actual current water / solid ratio is greater than the target ratio, more slurry (with entrained solids) is needed to reduce water dilution and increase its solids content. Therefore, controller 300 can briefly open isolation valve 525 to add an additional amount of slurry from grinder 110 to mixing chamber 502. Steps (1) and (2) are repeated as needed until the target ratio is met.

[0096] In some embodiments, when permissible, a predetermined + / - deviation in the target water / solid ratio can be programmed into the controller 300 such that if the measured actual water / solid ratio is not greater than or less than a programmed tolerance percentage, it can be considered to meet the target water / solid ratio for sample analysis. Therefore, in some embodiments, the controller can use a water / solid ratio within an acceptable target range, rather than a single absolute value of the target ratio.

[0097] It is worth noting that, in some embodiments, the pump 120, which pumps the stirring chamber 502 to transfer the slurry to the analysis unit 140, can also be used to recirculate a portion of the sample slurry via the recirculation line 120a, and to add water to the recirculated slurry from an external water source (see, for example...). Figure 9 This is a means of adjusting (i.e. reducing) the water / solid ratio of the sample slurry in the stirring chamber 502.

[0098] The spectrometer 550 can also be used to identify other characteristics of the sample, including but not limited to soil structure (e.g., sand content), color distribution, and organic matter content. By monitoring the reflectance of the sample under various levels of agitation, the characteristics of individual components of the sample can also be measured (e.g., by stopping agitation of the sample and allowing heavy particles to settle downwards onto the lens 551 of the spectrometer).

[0099] Once the desired target water-to-solids mass ratio of the slurry is achieved, the sample slurry is ready for chemical analysis. The stirring apparatus 500 includes a vertically extending filtrate suction pipe 521 through which a pump 120 (in one embodiment, a slurry pump) can extract the slurry from the internal cavity 530 of the stirring chamber 502 via one or more filtrate outlet ports 520. In one embodiment, multiple outlet ports may be provided, fluidly connected to the vertical suction pipe 521 via a branch flow manifold 521a, as shown. Using multiple smaller filtrate outlet ports allows for the simultaneous extraction of several samples from the stirring chamber 502, enabling different sections of the analytical unit to test different analytes simultaneously in parallel. In other embodiments, a single larger filtrate outlet port may be used instead. The filtrate outlet port 520 may be located in the upper housing section 511 of the stirring apparatus and may extend laterally through the upper housing section (see, for example...). Figure 22-23 As shown in the figure, the filtrate suction tube 521 is suspended from the upper housing section 511, such that the weight of the tube is preferably supported solely by the upper housing section. This support configuration does not increase the weight of the mixing chamber when the slurry is weighed via the strain gauge 504, as described elsewhere herein. In other possible embodiments, the filtrate outlet port 520 may alternatively be located in the side wall of the lower housing section 512 (mixing chamber 502), such that the filtrate suction tube 521 is then supported by the mixing chamber, and its weight is taken into account when weighing the slurry.

[0100] However, the sample slurry may contain particles that are too large to be tolerated by the small openings and flow lines within the analysis unit 140. This could lead to problems in downstream analytical equipment, such as blockage / clogging. Therefore, a combination of filtration and separation features / measures can be implemented in the stirring chamber 502 to prevent potentially problematic particles (solids) from leaving the chamber and entering the analytical equipment.

[0101] In one embodiment, the filtration feature may include a slurry secondary filter 522 (the grinder 110 is used as a primary filter for large particle separation). Filter 522 is positioned... Figure 9 Upstream of pump 120 in the slurry flow circuit shown. In one embodiment, filter 522 may be disposed inside the mixing chamber 502 and may be connected to a filtrate suction pipe 521 within the inner cavity 530 of the mixing chamber. For example, filter 522 may be connected to the bottom inlet end of suction pipe 521 suspended from above into the inner cavity 530 of the mixing chamber and suspended above the bottom of the cavity (see, for example...). Figure 22In one embodiment, filter 522 may be a mesh filter comprising a screen with a plurality of mesh openings sized to prevent solid particles exceeding a predetermined maximum size from being drawn into the filtrate suction tube 521 and carried downstream. Thus, the size of the screen openings in such a filter is formed to be proportional to the minimum flow channel of the analytical device of analytical unit 140, so as not to allow particles exceeding the minimum flow channel size (e.g., diameter) to pass through.

[0102] Separation features include limiting the rotational speed of stirrer 250 so that the heaviest (largest) particles in the sample slurry are not lifted high enough in the slurry column to be attracted toward and onto the secondary filter 522, which is located and suspended a certain vertical distance above the floor or bottom of the inner cavity 530 of the stirring chamber. Otherwise, this could lead to frequent clogging of the small mesh openings of the filter. Stirring is still required to promote chemical homogeneity in the sample, but is limited to stirring the slurry gently enough to leave large and chemically insignificant particles below the secondary filter at the bottom of the stirring chamber. Therefore, the maximum rotational speed of stirrer 250 is selected to keep large particles of sample solids at the bottom of the stirring chamber 502, which prevents large particles from being attracted to the secondary filter 522. In other words, the stirrer is configured and operable to stir the slurry at a selected maximum speed via blades 253 such that at least some of the larger particles are desuspended from the slurry and aggregate at the bottom of the inner cavity 530 of the stirring chamber.

[0103] To further help prevent slurry solid particles from being attracted to the filter 522, the bottom or floor 530a of the internal cavity 530 of the mixing chamber may be tilted left or right, such that the portion of the floor below the filter is lower than the portion of the floor below the agitator blades 253 (see example). Figure 21 A recess or depression is formed in the deeper portion of the internal cavity 530 of the agitation chamber below the filtrate suction pipe 521 and filter 522, allowing larger particles to detach from suspension and settle, aggregating instead of being drawn upward toward the filter 522. Additionally, the waste port 543 can be connected to this deeper portion of the internal cavity 530 of the agitation chamber below the filter 522 to more effectively flush residual solids with water between slurry processing runs. Therefore, the inclined floor 530a of the agitation chamber 502 provides multiple functions and benefits.

[0104] In some embodiments, a vacuum sensor 523 may be positioned upstream of pump 120, between secondary filter 522 and pump, to allow detection of clogged secondary filter screens. In one embodiment, vacuum sensor 523 may be fluidly coupled to and positioned on filtrate suction line 521 on the downstream filtrate side of secondary filter 522. The vacuum sensor is operatively coupled to programmable controller 300 to provide automatic detection of clogged / blocked filter 522. The controller can then terminate slurry extraction from stirring chamber 502 by stopping operation of pump 120 until the clogged filter can be cleaned. In other embodiments, vacuum sensor 523 may be fluidly coupled to flow line 120b between pump 120 and stirring chamber 502 (see reference). Figure 9 ).

[0105] In an alternative embodiment, pump 120 can be completely omitted, and the slurry filtrate can flow from stirring chamber 502 to analysis unit 140 by gravity for the processing and analysis of various analytes or other relevant properties of agricultural samples.

[0106] As mentioned above, the stirring device may include a filter, for example (but not limited to) Figure 22 The filter 522 is designed to prevent solid particles larger than a predetermined size from being passed downstream. However, with normal use, such a filter may become clogged with particles.

[0107] Figure 25-35 Two example systems and corresponding methods for cleaning such filters or other types of filters or other devices for agitation apparatus are disclosed. Figure 25-29 A first embodiment of such a system is discussed. This first embodiment is based on... Figure 9-24 System 520 is used to process agricultural slurry received from a source (such as grinder 110), but the invention can also be applied to different systems for processing agricultural slurry. Specifically, the first embodiment... Figure 9-24 The system adds an ultrasonic transducer 560 to clean the filter 522 of the stirring device 500. The filter 522 is fluidly connected to the outlet port 520 and is positioned within the internal cavity 530 of the stirring chamber 502 to filter the slurry.

[0108] Such as about Figure 9-24The system under discussion may include a mixing chamber 502 having a housing 510 defining an internal cavity 530 configured to receive agricultural sample slurry. The illustrated mixing chamber 502 also includes a vertically extending filtrate suction pipe 521 through which a pump 120 (in one embodiment, a slurry pump) can extract slurry from the internal cavity 530 of the mixing chamber 502 via one or more filtrate outlet ports 520. This embodiment also includes a filter 522 that filters... Figure 9 The slurry flow loop shown is located upstream of pump 120. As discussed in more detail above, filter 522 can be disposed within stirring chamber 502 and can be connected to filtrate suction pipe 521 within the internal cavity 530 of stirring chamber 502. Filter 522 can be a mesh filter, comprising a screen with multiple mesh openings sized to prevent solid particles exceeding a predetermined maximum size from being drawn into filtrate suction pipe 521 and carried downstream. It should be noted that filter 522 typically has a larger mesh size than... Figure 25-29 The sieve shown is a finer sieve to block smaller particles, but such a finer sieve is not shown. It should also be noted that in other embodiments, other types and shapes of filters can be used. For example, the invention can be used to clean filters attached to a stirring chamber, rather than filters suspended in the stirring chamber, and the filtrate line outlet port can extend from the side of the chamber. It should also be noted that the invention is not limited to stirring chambers using filtrate suction pipes and can be applied to a variety of filters.

[0109] The ultrasonic transducer 560 can be installed into the housing 510 of the stirring chamber 502. This is in Figure 26 The best view is shown below. (Note that this is for easier viewing.) Figure 25 (The housing 510 is omitted.) In the illustrated embodiment, the ultrasonic transducer 560 is mounted to the outer wall 510A of the housing 510 of the stirring chamber 502, but the invention is not limited thereto. The illustrated ultrasonic transducer 560 is mounted such that the front portion 561A of the front drive element 561 passes through the housing 510 of the stirring chamber 502, allowing it to be positioned close to or in physical contact with the filter 522. The front portion 561A of the front drive element 561 of the ultrasonic transducer 560 may include a groove 567 and an O-ring 564 configured to fit within the groove 567 to seal liquid within the internal cavity 530 of the stirring chamber 502. In other embodiments, other means of sealing liquid within the internal cavity 530 may be utilized.

[0110] In the illustrated embodiment, the ultrasonic transducer 560 is positioned close to the filter 522. In some embodiments, the distance D between the ultrasonic transducer 560 and the filter 522 is 2 inches or less. Generally, the smaller the distance D, the better the ultrasonic cleaning effect. The proximity required for effective cleaning will depend on the transducer power and the pressure required for a particular cleaning task. The filter 522, along with other components of the stirring chamber 502, can be mechanically isolated from the rest of the stirring apparatus 500 when the ultrasonic transducer 560 is not in contact with the filter. In such an embodiment, the ultrasonic transducer 560 may be physically attached to the lower housing 512 of the stirring chamber 502, while the filter 522 is not physically attached to the stirring chamber 502.

[0111] The ultrasonic transducer 560 can be configured to induce cavitation bubble formation when the ultrasonic transducer 560 is activated and the filter is immersed in the liquid. In the illustrated embodiment, the ultrasonic transducer 560 vibrates along a first axis A perpendicular to the outer wall 510A of the housing 510 of the stirring chamber 502 when activated. Mechanical oscillations are transmitted to the liquid, causing bubble formation and collapse. Each collapse creates a localized high-pressure region, which can reach thousands of psi. The frequency used for ultrasonic cleaning is typically 10-100 kHz, but any frequency within this range, as well as other frequencies, can be used. In one embodiment, 28 kHz is used, which is at the lower end of this range but avoids the audible spectrum. In other embodiments, other frequencies in the lower band of the 10-100 kHz spectrum are used. In some embodiments, lower frequencies are preferred because they produce larger cavitation bubbles, each with higher energy. In contrast, higher frequencies produce more cavitation bubbles, but each bubble has lower energy. It should be noted that the liquid in which cavitation bubbles form may include or omit the cleaning solution. It should also be noted that, in alternative embodiments, cleaning can be performed without the use of cavitation bubbles. For example, cleaning can be performed using physical vibration (ultrasound or other methods).

[0112] The ultrasonic transducer 560 is designed to focus energy where it is most needed by the cleaning filter 522. Figure 25-29In the illustrated embodiment, the ultrasonic transducer 560 has a front end 560A and a rear end 560B. The ultrasonic transducer 560 includes a front drive element 561, a rear drive element 562, two piezoelectric elements 563 positioned between the front drive element 561 and the rear drive element 562, and a bolt 569 configured to pass through at least a portion of each of the front drive element 561, the rear drive element 562, and the two piezoelectric elements 563. The ultrasonic transducer 560 also includes an insulating sleeve 565 surrounding a portion of the bolt 569 to prevent the bolt 569 from physically contacting the two piezoelectric elements 563. The insulating sleeve 565 comprises a dielectric material. In the illustrated embodiment, the two piezoelectric elements comprise a conductive piezoelectric ceramic material.

[0113] The front drive element 561 (sometimes referred to as a horn) has a front portion 561A near the front end 560A of the ultrasonic transducer 560 and an opposite rear portion 561B. The cross-sectional area A1 of the front portion 561A of the front drive element 561 is smaller than the cross-sectional area A2 of the rear portion 561B of the front drive element 561, wherein each cross-sectional area A1, A2 is perpendicular to the first axis.

[0114] In an exemplary embodiment, the front portion 561A of the front drive element 561 is formed as a first cylinder, and the rear portion 561B of the front drive element 561 is formed as a second cylinder different from the first cylinder. The first cylinder 561A has a circular cross-section, the area A1 of which is smaller than the area A2 of the circular cross-section of the second cylinder 561B. However, it should be noted that the present invention is not limited to these cylindrical shapes, as shown in the second embodiment discussed below.

[0115] By reducing the cross-sectional area of ​​the front drive element 561, the smaller front portion 561A vibrates more than the larger rear portion 561B. This design helps to focus energy onto the filter, thereby helping to ensure that most cavitation bubbles form on or near the filter 522, thus improving the quality of ultrasonic cleaning of the filter 522. Figure 27 The front portion 561A of the front drive element 561 is shown to have an area A1 large enough to surround the bottom portion of the filter 522, but not larger. Since the bottom is the most likely part of the filter 522 to become clogged, focusing on the bottom of the filter 522 may be preferable.

[0116] In some embodiments, the front drive element 561 may comprise aluminum, and the rear drive element 562 may comprise stainless steel. Furthermore, the mass of the front drive element 561 may be 5% greater or less than the mass of the rear drive element 562. Additionally, the density of the rear drive element 562 may be higher than that of the front drive element 561. However, the invention is not therefore limited to any of these specific exemplary features.

[0117] An exemplary ultrasonic transducer 560 also includes a housing 566 surrounding a portion of a front drive element 561, a rear drive element 562, two piezoelectric elements 563, and bolts 569. The housing 566 of the ultrasonic transducer 560 may also include a mounting bracket 568 configured to mount the ultrasonic transducer 560 to a housing 510 of a stirring chamber 502. As shown, the housing 566 includes an aperture 568B through which screws 568A or other fastening elements can pass to secure the ultrasonic transducer 560 to the housing 510. It should be noted that the mounting bracket 568 can also serve as a cap for the housing 566 of the ultrasonic transducer 560.

[0118] Figures 30-34 A second embodiment of a system for cleaning the filter of a stirring device is disclosed. This second embodiment is related to... Figure 25-29 The first embodiment shown has many similarities, therefore many of the same reference numerals are used to denote the same or substantially similar parts and features, and descriptions of these similar parts and features will not be repeated here. Instead, the following discussion is limited to the main differences between the first and second embodiments.

[0119] The main difference between the embodiments is that the ultrasonic transducer 560-2 of the second embodiment has a front drive element 561-1 with a different shape than the front drive element 561 of the first embodiment. Specifically, the front portion 561A-2 of the front drive element 561-2 has a rectangular cross-section instead of a circular cross-section. Figure 32 As most clearly shown, this allows the cross-sectional area A1-2 of the front portion 561A-2 to more closely match the shape of the filter 522. It should be noted that in this embodiment, the cross-sectional area A2-2 of the rear portion 561B-2 of the front drive element 561-2 remains circular and is still larger than the cross-sectional area A1-2 of the front portion 561A-2. Finally, it should be noted that alternative grooves 567-2 and O-rings 564-2 can be used to seal the liquid within the internal cavity 530.

[0120] Figure 35A method for cleaning a filter of a stirring apparatus for agricultural sample slurry is illustrated. The method includes the following operations: positioning an ultrasonic transducer near or in physical contact with the filter of the stirring apparatus (operation 591); stirring the agricultural sample slurry within the stirring apparatus, which includes the filter (operation 592); immersing the filter of the stirring apparatus in a liquid (operation 593); and activating the ultrasonic transducer to form cavitation bubbles in the liquid and thereby clean the filter (operation 594). These operations do not need to be performed in this order. Operations 592-594 can be repeated, allowing ultrasonic cleaning to be performed after each new slurry passes through. It should also be noted that the method may further include a sensor for sensing blockage and thereby triggering filter cleaning. As mentioned above, in other embodiments, the cleaning method may be based on physical vibration of the filter caused by the ultrasonic transducer, rather than on the generation of cavitation bubbles. Furthermore, while in some embodiments cleaning occurs after the filter has finished processing the slurry, in other embodiments, cleaning induced by the ultrasonic transducer can be performed while the filter is actively processing the slurry.

[0121] The disclosed systems and methods for cleaning filters in agitated chambers offer several advantages. For example, they enable high-pressure cleaning of the filter without disassembling the agitated chamber or providing physical access to the filter. While high-pressure water can be used alternatively to clean the filter, this method requires fluid flow. The ultrasonic cleaning systems and methods described herein enable high-pressure cleaning without fluid flow.

[0122] The systems disclosed herein for analyzing agricultural samples can be used and can form part of a general agricultural sampling and analysis system, such as, but not limited to, those described in the following documents: U.S. Patent Application Publications US2018 / 0124992A1, US20210123836A1, US20210123936A1, US20210131917A1, US20210131929A1, US20210208035A1, U... S20210208036A1, US20210208037A1, US20210208123A1, US20210268456A1, US20210285869A1, US2 0210341442A1, US20210341452A1, US20220196628A1, US20230133335A1, US20230144670A1, US2023 0151810A1, US20230173415A1, US20230243792A1, US20230243801A1, US20230243802A1, US202302 43804A1, US20230266289A1, US20230266290A1, US20230273130A1, US20230273171A1, US202302731 72A1, US20230273173A1, US20230304987A1, US20230417363A1, US20230417635A1, US20240189743 A1, US20240189744A1, US20240192112A1, US20240192708A1, US20240198331A1, US20240200547A1;PCT records released: WO2021 / 171120, WO2021 / 171121, WO2022 / 243792, WO2022 / 243797, WO2022 / 243806, WO2022 / 243807, WO2022 / 243809, WO2022 / 259071, WO2022 / 259073 , WO2022 / 259074, WO2023 / 031725, WO2023 / 031726, WO2023 / 031727, WO2023 / 0 42032, WO2023 / 042033, WO2023 / 042035, WO2023 / 042036, WO2023 / 042037, WO20 23 / 042038, WO2023 / 042039, WO2023 / 161727, WO2023 / 161728, WO2023 / 170480 , WO2023 / 170482, WO2023 / 227959, WO2023 / 227960, WO2023 / 248015, WO2023 / 2 48016, WO2024 / 023728, WO2024 / 023729, WO2024 / 023730 and WO2024 / 023731; PCT Application PCT / IB2024 / 051283, submitted on February 12, 2024, PCT / IB2024 / 051820, submitted on February 26, 2024;U.S. petitions filed on February 8, 2024: 63 / 551120; 63 / 552730; 63 / 552739; 63 / 559305; 63 / 559308; 63 / 559312; 63 / 559316; 63 / 586486; and 63 / 586489. Submitted on September 29, 2023, 63 / 586497; submitted on September 29, 2023, 63 / 586500; submitted on September 29, 2023, 63 / 586504; submitted on September 29, 2023, 63 / 586510; submitted on September 29, 2023, 63 / 586514; submitted on September 29, 2023, 63 / 586524; submitted on October 11, 2023, 63 / 586529; submitted on September 29, 2023, 63 / 586545; submitted on September 29, 2023. Submitted on September 29, 2023, with numbers 63 / 586551, 63 / 586555, 63 / 586562, 63 / 586608, 63 / 586619, 63 / 586630, 63 / 586638, 63 / 586656, and 63 / 586672. Submitted on September 29, 2023, 63 / 586702; submitted on September 29, 2023, 63 / 586726; submitted on September 29, 2023, 63 / 586955; submitted on September 29, 2023, 63 / 586966; submitted on September 29, 2023, 63 / 586978; submitted on September 29, 2023, 63 / 586984; submitted on September 29, 2023, 63 / 586990; submitted on September 29, 2023, and 63 / 646070; and submitted on May 13, 2024.

[0123] Example

[0124] The following are non-restrictive examples.

[0125] Example 1: A system for processing agricultural slurry, the system comprising: an agricultural sample slurry source; a stirring device including: a stirring chamber including: a housing defining an internal cavity configured to receive the agricultural sample slurry; one or more outlet ports configured to release slurry from the internal cavity; a filter fluidly coupled to the one or more outlet ports and positioned within the internal cavity of the stirring chamber to filter the slurry; and an ultrasonic transducer positioned proximate to or in physical contact with the filter.

[0126] Example 2: According to the system described in Example 1, the ultrasonic transducer is configured to cause cavitation bubbles to form when the ultrasonic transducer is activated and the filter is immersed in a liquid.

[0127] Example 3: According to the system of Example 1, the stirring chamber further includes a filtrate suction tube configured to extract slurry from the internal cavity through the one or more outlet ports.

[0128] Example 4: The system according to Example 1, wherein the ultrasonic transducer is mounted on the wall of the housing of the stirring chamber.

[0129] Example 5: A system according to any of the preceding examples, wherein there is a distance between the ultrasonic transducer and the filter such that the ultrasonic transducer and the filter are not in physical contact.

[0130] Example 6: A system according to any one of the preceding examples, wherein the ultrasonic transducer vibrates along a first axis perpendicular to the outer wall of the housing of the stirring chamber when activated.

[0131] Example 7: A system according to any one of the preceding examples: wherein the ultrasonic transducer includes a front drive element located at the front end of the ultrasonic transducer; wherein the front drive element has a front portion near the front end of the ultrasonic transducer and an opposite rear portion; and wherein the cross-sectional area of ​​the front portion of the front drive element is smaller than the cross-sectional area of ​​the rear portion of the front drive element, wherein each cross-sectional area is parallel to the outer wall of the housing of the stirring chamber.

[0132] Example 8: According to the system of Example 7, the front portion of the front drive element is formed as a first cylinder, and the rear portion of the front drive element is formed as a second cylinder different from the first cylinder, the first cylinder having a circular cross-section, the circumference of the circular cross-section of the first cylinder being smaller than the circumference of the circular cross-section of the second cylinder.

[0133] Example 9: According to the system of Example 7, the front portion of the front drive element of the ultrasonic transducer includes a groove; and the ultrasonic transducer further includes an O-ring configured to fit within the groove of the front drive element to seal liquid within the inner cavity of the stirring chamber.

[0134] Example 10: A system according to any one of the preceding examples, wherein the ultrasonic transducer comprises: a front drive element; a rear drive element; two piezoelectric elements positioned between the front drive element and the rear drive element; a bolt configured to pass through at least a portion of the front drive element, the rear drive element, and each of the two piezoelectric elements; and an insulating sleeve surrounding a portion of the bolt to prevent the bolt from contacting the two piezoelectric elements, the insulating sleeve comprising a dielectric material.

[0135] Example 11: According to the system of Example 10, the ultrasonic transducer further includes a housing surrounding at least a portion of each of the front drive element, the rear drive element, the two piezoelectric elements, and the bolt.

[0136] Example 12: According to the system of Example 11, the housing of the ultrasonic transducer further includes a mounting bracket configured to mount the ultrasonic transducer to the outer wall of the housing of the stirring chamber.

[0137] Example 13: The system according to Example 10, wherein the front drive element comprises aluminum and the rear drive element comprises stainless steel.

[0138] Example 14: In the system according to Example 10, the mass of the front drive element is the mass of the rear drive element plus or minus 5%.

[0139] Example 15: The system according to Example 10, wherein the density of the rear drive element is higher than the density of the front drive element.

[0140] Example 16: The system according to Example 10, wherein each of the two piezoelectric elements comprises a conductive piezoelectric ceramic material.

[0141] Example 17: The system according to any one of the foregoing examples, wherein the agricultural slurry sample source includes a grinder.

[0142] Example 18: According to the system of Example 3, the filter includes a mesh screen with an opening sized to prevent solid particles exceeding the maximum size from being drawn into the filtrate suction tube.

[0143] Example 19: According to the system of Example 18, the stirring device further includes a vacuum sensor disposed upstream of the pump between the pump and the filter, the vacuum sensor being operable to detect vacuum conditions indicating the clogging status of the filter.

[0144] Example 20: The system according to Example 3: wherein the housing of the stirring chamber includes an upper housing section and a lower housing section; and wherein one or more filtrate outlet ports are disposed in the upper housing section of the stirring device, and the filtrate suction tube is suspended from the upper housing section in the internal cavity of the stirring chamber.

[0145] Example 21: The system according to Example 20, wherein the filtrate suction tube extends vertically from at least the top portion of the stirring chamber into the lower portion of the inner cavity of the stirring chamber.

[0146] Example 22: According to the system of Example 21, wherein the filtrate suction tube is fluidly connected to a pump via the filtrate outlet port, the pump being operable to apply suction to the filtrate suction tube for extracting slurry from the stirring chamber.

[0147] Example 23: The system according to Example 22, wherein at least a portion of the extracted slurry is transferred to an analysis unit.

[0148] Example 24: The system according to any one of the foregoing examples, wherein the stirring device further includes a strain gauge structurally coupled to the stirring chamber, the strain gauge being configured and operable to measure the weight of the stirring chamber in the presence and absence of slurry.

[0149] Example 25: The system according to Example 24, wherein the strain gauge independently supports the stirring chamber, which is mechanically isolated from other parts of the stirring device.

[0150] Example 26: The system according to any one of the foregoing examples, wherein the stirring device further includes a stirrer comprising a rotatable stirrer shaft with blades disposed in the inner cavity of the stirring chamber and a motor operatively coupled to the stirrer shaft.

[0151] Example 27: An ultrasonic transducer for causing the formation of cavitation bubbles in a liquid, the ultrasonic transducer comprising: a front drive element; a rear drive element; two piezoelectric elements positioned between the front drive element and the rear drive element; a bolt configured to pass through at least a portion of the front drive element, the rear drive element, and each of the two piezoelectric elements; and an insulating sleeve surrounding a portion of the bolt to prevent the bolt from contacting the two piezoelectric elements, the insulating sleeve comprising a dielectric material; wherein the ultrasonic transducer vibrates along a first axis; wherein the front drive element has a front portion near the front end of the ultrasonic transducer and an opposing rear portion; and wherein the cross-sectional area of ​​the front portion of the front drive element is smaller than the cross-sectional area of ​​the rear portion of the front drive element, wherein each cross-sectional area is perpendicular to the first axis.

[0152] Example 28: The ultrasonic transducer according to Example 27, wherein the front portion of the front drive element is formed as a first cylinder, and the rear portion of the front drive element is formed as a second cylinder different from the first cylinder, the first cylinder having a circular cross-section, the circumference of the circular cross-section of the first cylinder being smaller than the circumference of the circular cross-section of the second cylinder.

[0153] Example 29: An ultrasonic transducer according to any one of Examples 27 to 28, wherein the ultrasonic transducer further includes a housing surrounding at least a portion of each of the front drive element, the rear drive element, the two piezoelectric elements, and the bolt.

[0154] Example 30: The ultrasonic transducer according to Example 29, wherein the housing of the ultrasonic transducer further includes a mounting bracket configured to mount the ultrasonic transducer to the outer wall of the housing of the stirring chamber.

[0155] Example 31: An ultrasonic transducer according to any one of Examples 27 to 30, wherein the front drive element comprises aluminum and the rear drive element comprises stainless steel.

[0156] Example 32: An ultrasonic transducer according to any one of Examples 27 to 31, wherein the mass of the front drive element is the mass of the rear drive element plus or minus 5%.

[0157] Example 33: An ultrasonic transducer according to any one of Examples 27-32, wherein the density of the rear drive element is higher than the density of the front drive element.

[0158] Example 34: An ultrasonic transducer according to any one of Examples 27-33, wherein each of the two piezoelectric elements comprises a conductive piezoelectric ceramic material.

[0159] Example 35: A method for cleaning a filter of a stirring apparatus for an agricultural sample slurry, the method comprising: positioning an ultrasonic transducer close to or in physical contact with a filter of the stirring apparatus; stirring the agricultural sample slurry in the stirring apparatus, the stirring apparatus including the filter; and activating the ultrasonic transducer to clean the filter.

[0160] Example 36: The method according to Example 35 further includes immersing the filter of the stirring device in a liquid, wherein activation of the ultrasonic transducer causes cavitation bubbles to form in the liquid and thereby cleans the filter.

[0161] Example 37: The method according to Example 36: wherein the filter is positioned within the stirring chamber of the stirring apparatus, the stirring chamber comprising: a housing defining an internal cavity configured to receive an agricultural sample slurry; and a filtrate suction tube configured to extract the slurry from the internal cavity through one or more filtrate outlet ports of the stirring apparatus; wherein the filter is fluidly coupled to the filtrate suction tube and positioned within the internal cavity of the stirring chamber to filter the slurry.

[0162] While the foregoing description and accompanying drawings represent some example systems, it is understood that various additions, modifications, and substitutions can be made thereto without departing from the spirit, scope, and equivalents of the appended claims. Specifically, those skilled in the art will readily recognize that embodiments of this disclosure can take other forms, structures, arrangements, proportions, dimensions, and other elements, materials, and components without departing from its spirit or essential characteristics. Furthermore, the methods / processes described herein can also be varied in many ways. Those skilled in the art will further understand that embodiments of this disclosure can be modified in structure, arrangement, proportion, dimensions, materials, and components, and other aspects, modifications which, in practice, are particularly suited to specific environments and operational requirements without departing from the principles of embodiments of this disclosure. Therefore, embodiments of this disclosure should be considered illustrative rather than restrictive in all respects, and the scope of embodiments of this disclosure is defined by the appended claims and their equivalents, and not limited to the foregoing description or embodiments. Rather, the appended claims should be interpreted broadly to include other variations and embodiments that may be made by those skilled in the art without departing from the scope and equivalents of embodiments of this disclosure.

Claims

1. A system for treating agricultural slurry, the system comprising: Agricultural sample slurry source; A stirring device, the stirring device comprising: The stirring chamber includes: A housing defining an internal cavity configured to receive an agricultural sample slurry; One or more outlet ports, the one or more outlet ports being configured to release slurry from the internal cavity; and A filter, fluidly coupled to the one or more outlet ports and positioned within the internal cavity of the agitation chamber to filter the slurry; and An ultrasonic transducer is positioned close to or in physical contact with the filter.

2. The system of claim 1, wherein the ultrasonic transducer is configured to cause cavitation bubbles to form when the ultrasonic transducer is activated and the filter is immersed in the liquid.

3. The system of claim 1, wherein the stirring chamber further comprises a filtrate suction pipe configured to extract slurry from the internal cavity through the one or more outlet ports.

4. The system of claim 1, wherein the ultrasonic transducer is mounted on the wall of the housing of the stirring chamber.

5. The system according to any one of the preceding claims, wherein a distance exists between the ultrasonic transducer and the filter such that the ultrasonic transducer and the filter are not in physical contact.

6. The system according to any one of the preceding claims, wherein the ultrasonic transducer vibrates along a first axis perpendicular to the outer wall of the housing of the stirring chamber when activated.

7. The system according to any one of the preceding claims: The ultrasonic transducer includes a front drive element located at the front end of the ultrasonic transducer; The front drive element has a front portion near the front end of the ultrasonic transducer and an opposing rear portion; and The cross-sectional area of ​​the front portion of the front drive element is smaller than the cross-sectional area of ​​the rear portion of the front drive element, wherein each cross-sectional area is parallel to the outer wall of the housing of the stirring chamber.

8. The system of claim 7, wherein the front portion of the front drive element is formed as a first cylinder, and the rear portion of the front drive element is formed as a second cylinder different from the first cylinder, the first cylinder having a circular cross-section, the circumference of the circular cross-section of the first cylinder being smaller than the circumference of the circular cross-section of the second cylinder.

9. The system according to claim 7: The front portion of the front drive element of the ultrasonic transducer includes a groove; and The ultrasonic transducer further includes an O-ring configured to fit within a groove of the front drive element to seal the liquid within the inner cavity of the stirring chamber.

10. The system according to any one of the preceding claims, wherein the ultrasonic transducer comprises: Front drive components; Rear drive components; Two piezoelectric elements are positioned between the front drive element and the rear drive element; Bolts, the bolts being configured to pass through at least a portion of each of the front drive element, the rear drive element, and each of the two piezoelectric elements; as well as An insulating sleeve surrounds a portion of the bolt to prevent the bolt from contacting the two piezoelectric elements, the insulating sleeve comprising a dielectric material.

11. The system of claim 10, wherein the ultrasonic transducer further comprises a housing surrounding at least a portion of each of the front drive element, the rear drive element, the two piezoelectric elements, and the bolt.

12. The system of claim 11, wherein the housing of the ultrasonic transducer further includes a mounting bracket configured to mount the ultrasonic transducer to an outer wall of the housing of the stirring chamber.

13. The system of claim 10, wherein the front drive element comprises aluminum and the rear drive element comprises stainless steel.

14. The system of claim 10, wherein the mass of the front drive element is the mass of the rear drive element plus or minus 5%.

15. The system of claim 10, wherein the density of the rear drive element is higher than the density of the front drive element.

16. The system of claim 10, wherein each of the two piezoelectric elements comprises a conductive piezoelectric ceramic material.

17. The system according to any one of the preceding claims, wherein the agricultural slurry sample source comprises a grinder.

18. The system of claim 3, wherein the filter comprises a mesh screen having an opening sized to prevent solid particles exceeding a maximum size from being drawn into the filtrate suction tube.

19. The system of claim 18, wherein the stirring device further comprises a vacuum sensor disposed upstream of the pump between the pump and the filter, the vacuum sensor being operable to detect vacuum conditions that indicate the clogging status of the filter.

20. The system according to claim 3: The shell of the stirring chamber includes an upper shell section and a lower shell section; and The one or more filtrate outlet ports are located in the upper housing section of the stirring device, and the filtrate suction pipe is suspended from the upper housing section in the inner cavity of the stirring chamber.

21. The system of claim 20, wherein the filtrate suction tube extends vertically from at least the top portion of the stirring chamber into the lower portion of the inner cavity of the stirring chamber.

22. The system of claim 21, wherein the filtrate suction tube is fluidly connected to a pump via the filtrate outlet port, the pump being operable to apply suction to the filtrate suction tube for extracting slurry from the mixing chamber.

23. The system of claim 22, wherein at least a portion of the extracted slurry is transferred to the analysis unit.

24. The system according to any one of the preceding claims, wherein the stirring device further comprises a strain gauge structurally coupled to the stirring chamber, the strain gauge being configured and operable to measure the weight of the stirring chamber in the presence and absence of slurry.

25. The system of claim 24, wherein the strain gauge independently supports the stirring chamber, the stirring chamber being mechanically isolated from other parts of the stirring apparatus.

26. The system according to any one of the preceding claims, wherein the stirring device further comprises a stirrer, the stirrer comprising a rotatable stirrer shaft with blades disposed in the inner cavity of the stirring chamber and a motor operatively coupled to the stirrer shaft.

27. An ultrasonic transducer for causing the formation of cavitation bubbles in a liquid, the ultrasonic transducer comprising: Front drive components; Rear drive components; Two piezoelectric elements are positioned between the front drive element and the rear drive element; Bolts, the bolts being configured to pass through at least a portion of each of the front drive element, the rear drive element, and each of the two piezoelectric elements; And an insulating sleeve surrounding a portion of the bolt to prevent the bolt from contacting the two piezoelectric elements, the insulating sleeve comprising a dielectric material; The ultrasonic transducer vibrates along the first axis; The front drive element has a front portion near the front end of the ultrasonic transducer and an opposite rear portion; and The cross-sectional area of ​​the front portion of the front drive element is smaller than the cross-sectional area of ​​the rear portion of the front drive element, wherein each cross-sectional area is perpendicular to the first axis.

28. The ultrasonic transducer of claim 27, wherein the front portion of the front drive element is formed as a first cylinder, and the rear portion of the front drive element is formed as a second cylinder different from the first cylinder, the first cylinder having a circular cross-section, the circumference of the circular cross-section of the first cylinder being smaller than the circumference of the circular cross-section of the second cylinder.

29. The ultrasonic transducer according to any one of claims 27 to 28, wherein the ultrasonic transducer further comprises a housing surrounding at least a portion of each of the front drive element, the rear drive element, the two piezoelectric elements, and the bolt.

30. The ultrasonic transducer of claim 29, wherein the housing of the ultrasonic transducer includes a mounting bracket configured to mount the ultrasonic transducer to an outer wall of the housing of the stirring chamber.

31. The ultrasonic transducer according to any one of claims 27 to 30, wherein the front drive element comprises aluminum and the rear drive element comprises stainless steel.

32. The ultrasonic transducer according to any one of claims 27 to 31, wherein the mass of the front drive element is the mass of the rear drive element plus or minus 5%.

33. The ultrasonic transducer according to any one of claims 27 to 32, wherein the density of the rear drive element is higher than the density of the front drive element.

34. The ultrasonic transducer according to any one of claims 27 to 33, wherein each of the two piezoelectric elements comprises a conductive piezoelectric ceramic material.

35. A method for a filter in a stirring apparatus for cleaning agricultural sample slurry, the method comprising: Position the ultrasonic transducer close to the filter of the stirring device or in physical contact with the filter of the stirring device. An agricultural sample slurry is stirred in a stirring device, the stirring device including a filter; and Activate the ultrasonic transducer to clean the filter.

36. The method of claim 35, further comprising immersing the filter of the stirring device in a liquid, wherein activation of the ultrasonic transducer causes cavitation bubbles to form in the liquid and thereby clean the filter.

37. The method of claim 36, wherein the filter is positioned within the stirring chamber of the stirring apparatus, the stirring chamber comprising: A housing defining an internal cavity configured to receive an agricultural sample slurry; And a filtrate suction tube, the filtrate suction tube being configured to extract slurry from the internal cavity through one or more filtrate outlet ports of the stirring device; The filter is fluidly connected to the filtrate suction pipe and positioned within the internal cavity of the stirring chamber to filter the slurry.

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