A reciprocating swing auger and method of sorting

Abstract

The application discloses a reciprocating swing spiral chute and a sorting method thereof, and relates to the field of mine mechanical equipment. The spiral chute comprises a spiral chute body and a driving mechanism. The driving mechanism drives the spiral chute body to reciprocate around the central axis with a swing amplitude A and a swing frequency f. The swing frequency f satisfies the formula: f>0. The swing amplitude A and the swing frequency f satisfy the formula: A / R>0.1 and A / R<0.5, wherein R is the radius of the spiral chute body. The upper limit constraint prevents the liquid film from separating from the chute bottom, and the lower limit constraint ensures that the additional shear rate reaches the effective sorting threshold. The driving mechanism drives the spiral chute body to periodically reciprocate in the positive and negative directions, so that the spiral chute body generates additional tangential motion relative to the ore pulp, the additional shear rate is superimposed in the liquid film, the total shear rate is improved, the Bingham shear stress is increased, the mineral particle loose layering is strengthened, the sorting precision and the concentrate recovery rate are improved, the inside mineral accumulation is avoided, and the energy consumption is effectively saved.

Description

Technical Field

[0001] This invention relates to the field of mining machinery and equipment, specifically to a reciprocating oscillating spiral chute and its sorting method. Background Technology

[0002] Spiral sluice concentrators are a type of film gravity separation equipment. Mineral particles, under the combined influence of fluid dynamics, centrifugal inertia, friction, and their own gravity, undergo stratification and banding on the spiral sluice surface. Mineral particles of different specific gravities ultimately form concentrate, middlings, and tailings zones from the inner to the outer edge, achieving effective mineral separation. During separation, the slurry undergoes a three-dimensional spiral rotation along the spiral sluice. As the slurry moves downwards along the spiral sluice, the bottom layer of liquid has a near-zero velocity due to high friction at the bottom of the sluice, while the surface layer has the highest velocity due to gravity. This velocity difference between the upper and lower liquid layers within the film creates a shearing effect, causing the mineral particles to loosen and stratify. However, in a static spiral sluice, the shear rate of the liquid flow within the film is entirely determined by the fixed geometric parameters of the equipment (spiral diameter, pitch, transverse inclination angle, etc.), and cannot be actively adjusted according to the ore properties. This results in insufficient stability of the separation fluid, inadequate bed loosening, and limited separation accuracy.

[0003] Some existing technologies have made improvements to address this problem. For example, Chinese patents CN209333946U and CN221157120U both disclose a rotating spiral chute. These solutions utilize a rotating motor to drive the spiral chute to rotate continuously at a uniform speed in either the forward or reverse direction, using external force to superimpose centrifugal force to enhance the shearing effect. However, the spiral chute in these solutions applies rotational motion in only one direction, which has a limited effect on loosening and stratifying minerals. Furthermore, unidirectional rotational motion easily leads to mineral accumulation on the inner side of the spiral chute, thus deteriorating the sorting effect. Based on this, the applicant, in research conducted under the National Natural Science Foundation of China project (Mechanism and Regulation of Spiral Inclined Surface Loss Based on Rolling Wave Theory), discovered that shearing with specific amplitude and frequency can improve the stability and sorting effect of spirally sorted fluids. Summary of the Invention

[0004] The purpose of this invention is to provide a reciprocating oscillating spiral chute and its sorting method to solve the following technical problems existing in the prior art: the shear rate of the liquid flow in the existing static spiral chute is completely determined by the fixed geometric parameters of the equipment and cannot be actively adjusted, resulting in insufficient stability of the sorted fluid, insufficient loosening of the bed, and limited sorting accuracy; the existing rotating spiral chute adopts a unidirectional rotational motion, which has limited effect on the loosening and stratification of minerals and easily leads to mineral accumulation on the inner side of the spiral chute; and the technical problem that the selection of oscillation parameters in the prior art depends on empirical values ​​and requires repeated adjustments.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: This invention provides a reciprocating oscillating spiral chute, comprising a spiral chute body and a driving mechanism; characterized in that the driving mechanism is drively connected to the spiral chute body, driving the spiral chute body to reciprocate around a central axis with an oscillation amplitude A and an oscillation frequency f; the oscillation frequency f satisfies The swing amplitude A and the swing frequency f satisfy the following condition: Where A is in degrees (°) and f is in Hz; R is the radius of the spiral chute body in meters (m), and .

[0006] Wherein, the central axis refers to the geometric central axis of the spiral chute body, the oscillation amplitude is the maximum angle at which the spiral chute body deflects from zero to one side, and the oscillation frequency is the number of cycles per second of reciprocating oscillation. The spiral chute body is driven by a drive mechanism to periodically oscillate in both directions around the central axis, causing additional tangential motion relative to the slurry within the chute. This creates an additional shear rate superimposed on the basic secondary circulation shear within the flow film, thereby actively enhancing the loose stratification of mineral particles. The parameter constraints are jointly determined by the critical condition (upper limit) of flow film stability and the effective shear threshold condition (lower limit), ensuring that the additional shear rate enhances the sorting effect without compromising the stability of the flow film.

[0007] Furthermore, the radius R of the spiral chute body is... The oscillation frequency satisfies This preferred parameter range corresponds to the most commonly used specifications of spiral chutes in industry. Within this range, the enhanced sorting effect of reciprocating oscillation is more stable and reliable.

[0008] In some embodiments, the spiral chute body is a single-head spiral chute or a multi-head spiral chute. The reciprocating oscillation technology provided by the present invention is applicable to both single-head and multi-head spiral chutes and is not limited by the number of spiral heads.

[0009] In some embodiments, the spiral chute body is fixedly mounted on a rotating shaft, which is mounted on a frame via a bearing housing. The drive mechanism is connected to the rotating shaft and drives the spiral chute body to reciprocate around its central axis by reciprocating the rotating shaft. The rotating shaft serves as an intermediate transmission component between the spiral chute body and the drive mechanism, reliably transmitting the reciprocating motion output by the drive mechanism to the spiral chute body.

[0010] In some embodiments, the drive mechanism includes a rotary motor and a crank-rocker mechanism. The crank-rocker mechanism includes a crank, a connecting rod, and a rocker arm. The output shaft of the rotary motor is fixedly connected to one end of the crank, the other end of the crank is hinged to one end of the connecting rod, the other end of the connecting rod is hinged to one end of the rocker arm, and the other end of the rocker arm is fixedly connected to the rotating shaft. When the rotary motor rotates at a constant speed, the crank performs circular motion, which drives the rocker arm to oscillate reciprocally via the connecting rod. The rocker arm then drives the rotating shaft and the spiral chute body to oscillate reciprocally around the central axis, thus converting the rotational motion into reciprocating oscillating motion.

[0011] Furthermore, the rocker arm is an adjustable-length rocker arm, and the swing amplitude A is set by adjusting the length of the rocker arm; the rotary motor adjusts its speed through a frequency converter to set the swing frequency f. The adjustable-length rocker arm simplifies the adjustment of the swing amplitude A, and the frequency converter speed control makes the setting of the swing frequency f flexible and controllable. The combination of the two allows the swing parameters to be precisely set within the effective range defined by the constraint relationship.

[0012] In some embodiments, the drive mechanism includes a hydraulic motor, a proportional valve, a hydraulic power unit, and a controller. The output shaft of the hydraulic motor is fixedly connected to the rotating shaft. The inlet of the proportional valve is connected to the hydraulic power unit, and the outlet of the proportional valve is connected to the hydraulic motor. The controller is electrically connected to the proportional valve and controls the valve core opening direction and opening area by sending control signals to the proportional valve to set the swing amplitude A and the swing frequency f. The hydraulic motor has a large output torque and is suitable for reciprocating swing drive scenarios of large and heavy-duty spiral chutes. By sending current signals or PWM wave signals to the proportional valve through the controller, the reciprocating rotational motion of the hydraulic motor can be precisely controlled.

[0013] In some embodiments, the drive mechanism includes a servo motor, a servo driver, a reducer, a coupling, and a control unit. The output shaft of the servo motor is fixedly connected to the reducer, and the output shaft of the reducer is fixedly connected to the rotating shaft via the coupling. The servo driver is electrically connected to the servo motor and outputs a drive signal to the servo motor. The servo motor is equipped with an encoder, which is electrically connected to the servo driver and provides feedback on the rotational position signal of the servo motor to the servo driver. The control unit is electrically connected to the servo driver and performs closed-loop position control on the servo motor through the servo driver to drive the rotating shaft to reciprocate. The servo motor with an encoder can provide real-time feedback on the actual angular displacement of the rotating shaft, forming closed-loop position control, which improves the control accuracy of the oscillation amplitude and oscillation frequency, making it suitable for applications with high precision requirements for sorting parameters.

[0014] This invention also provides a reciprocating oscillating sorting method for a spiral chute, comprising the following steps: setting the oscillation amplitude and oscillation frequency of the spiral chute body, wherein the oscillation frequency satisfies The swing amplitude A and the swing frequency f satisfy the following condition: Where R is the radius of the spiral chute body; the spiral chute body is driven to oscillate back and forth around the central axis with the oscillation amplitude A and the oscillation frequency f; the slurry is continuously fed from the feed end of the spiral chute body, and the mineral particles are loosely separated into layers under the combined action of gravity, centrifugal force, friction, and the shear force and vibration force generated by the reciprocating oscillation of the spiral chute body surface. Mineral particles of different specific gravities and particle sizes form stable concentrate belts, middlings belts and tailings belts on the spiral chute surface, which are discharged through the ore blocks to different discharge outlets.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. The spiral chute body is driven by a drive mechanism to periodically oscillate back and forth around the central axis, causing the spiral chute body to generate additional tangential motion relative to the slurry. This creates an additional shear rate superimposed on the basic shear rate within the flow film, significantly increasing the total shear rate and the Begno shear stress. This effectively strengthens the loose stratification of mineral particles, improves the stability and sorting accuracy of the sorting fluid, and overcomes the shortcomings of existing static spiral chutes where the shear rate is determined by fixed geometric parameters and cannot be actively adjusted. 2. By constraining the oscillation amplitude and oscillation frequency within the effective parameter range, the upper limit constraint ensures that the lateral component of the additional tangential inertial force does not exceed the lateral component of gravity, preventing the liquid film from detaching from the bottom of the tank or causing splashing; the lower limit constraint ensures that the additional shear rate is not lower than the effective sorting threshold, guaranteeing the sorting enhancement effect; the two work together to enable the reciprocating oscillation to achieve effective sorting enhancement without destroying the stability of the flow film, solving the problem of lack of theoretical basis for the selection of oscillation parameters. 3. The reciprocating oscillation adopts a periodic alternating forward and reverse motion mode. Under the action of the additional tangential force of alternating forward and reverse motion, the slurry is subjected to symmetrical periodic disturbance, which effectively breaks up mineral particle clusters and avoids the defect of the existing unidirectional rotating spiral chute that causes mineral accumulation on the inner side due to continuous unidirectional rotation, thus improving the sorting quality of the inner concentrate area. 4. The drive mechanism can be implemented in various ways, such as a combination of rotary motor and crank-rocker mechanism, hydraulic motor or servo motor, which is suitable for spiral chute mineral processing machines of different specifications and working conditions and has strong engineering adaptability. Among them, the crank-rocker mechanism scheme has a simple structure and low total energy consumption and cost, the hydraulic motor scheme is suitable for large and heavy equipment, and the servo motor scheme has high-precision closed-loop control capability, which can be flexibly selected according to actual needs. Attached Figure Description

[0016] Figure 1A schematic diagram of the effective parameter region of spiral chute bodies of different diameters in the coordinate system of swing amplitude and swing frequency; Figure 2 This is a schematic diagram of the overall structure of the present invention; Figure 3 This is a schematic diagram of the overall structure of the drive scheme of the rotary motor and crank-rocker mechanism in Embodiment 1; Figure 4 This is a schematic diagram of the overall structure of the hydraulic motor drive scheme in Example 2; Figure 5 This is a schematic diagram of the overall structure of the servo motor drive scheme in Embodiment 3; Figure 6 This is a schematic diagram of the process for the spiral chute reciprocating oscillating sorting method.

[0017] Explanation of reference numerals in the attached drawings: 1. Spiral chute body; 2. Drive mechanism; 3. Rotary shaft; 4. Rotary motor; 5. Crank-rocker mechanism; 51. Crank; 52. Connecting rod; 53. Adjustable rod-length rocker; 6. Frame; 7. Ore receiving trough; 8. Frequency converter; 9. Hydraulic motor; 10. Proportional valve; 11. Hydraulic station; 12. Controller; 13. Servo motor; 14. Servo driver; 15. Reducer; 16. Coupling; 17. Control unit. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Before explaining the specific implementation methods, the mechanical mechanism of reciprocating oscillation-enhanced sorting and the derivation of the oscillation parameter constraint relationship will be explained first: I. Basic Mechanical Model of Spiral Chute Sorting In a stationary spiral chute, when the slurry rotates along the spiral chute, it is mainly subjected to force fields such as the tangential component of gravity, centrifugal force, and three-dimensional shear of secondary circulation. The tangential component of gravity drives the slurry to flow longitudinally along the chute surface, the centrifugal force drives the mineral particles to move towards the outer edge, and the three-dimensional shear generated by the secondary circulation is the core factor in separating fine-grained minerals.

[0020] The shear stress of the secondary circulation can be described as: ; in: Indicates the dynamic viscosity of the slurry. This represents the velocity gradient of the transverse flow velocity in the direction perpendicular to the channel surface. This represents the velocity gradient of the tangential flow velocity in the radial direction. This shear stress creates a velocity gradient within the flow film. It can be described as: In the Begno theory, shear rate This generates normal stress (Begano dispersion pressure) perpendicular to the shear direction and tangential stress (Begano shear stress) parallel to the shear direction. The Begno dispersion pressure loosens the mineral particles in the flow film, providing space for the stratification of light and heavy minerals according to their specific gravity, thus determining the feasibility of sorting. This can be described as follows: ; in: Indicating the Baigno experience, Indicates particle density, Indicates particle diameter, Indicates shear rate; The Begno shear stress drives the mineral particles in the loose layer to undergo lateral shearing motion, causing the light and heavy minerals to separate radially, determining the lower limit of the effective sorting particle size, which can be described as: ; in: This is the Begnostic empirical coefficient; II. Applying a reciprocating oscillating spiral chute mechanical model Applying a sinusoidal angular displacement to the spiral chute and causing it to reciprocate, the angular displacement curve is described as follows: ; in: Indicates the amplitude of the oscillation, in radians; Indicates the oscillation frequency. Indicates the swing time.

[0021] Angular velocity can be described as: ; Angular acceleration can be described as: ; quality is The axis distance is The additional tangential inertial force experienced by the mineral element can be described as follows: ; The additional tangential inertial force F generates periodic disturbances to the mineral particles, which helps to break up particle clusters.

[0022] Furthermore, the reciprocating oscillation of the spiral chute causes additional motion relative to the slurry body. The additional shear rate formed within the slurry with a film thickness of h can be described as follows: ; Over a complete cycle, the average absolute additional shear rate can be described as: ; The total shear rate can be described as: ; Substitute the Begno shear stress: ; The shear stress of the spiral chute after adding reciprocating oscillation and the shear stress of the static spiral chute In comparison, shear stress increases and . and Proportional to each other, it can effectively enhance shear stress, while Proof that applying a certain oscillation amplitude to the spiral chute and oscillation frequency The reciprocating oscillating motion can effectively enhance the shearing effect of the spiral chute.

[0023] III. Lowering the lower limit of effective sorting particle size When the shear stress on fine mineral particles Greater than the adhesive force that prevents its separation With settlement resistance The sum of these factors allows for the effective separation of minerals.

[0024] The total shear force on the mineral particles can be described as: ; in: Represents the shear area, shear area Therefore: ; Due to adhesion Settlement resistance ,in For slurry density, For effective mineral separation, the following conditions must be met, given the acceleration due to gravity: ; Therefore, we get: ; From this, the critical particle size of the mineral particles can be obtained: in, A coefficient representing the combined effects of adhesion constant, gravitational acceleration, and slurry properties, i.e., critical particle size. With total shear rate It increases and then decreases sharply.

[0025] IV. Optimal Region of Oscillation Parameters (1) The actual range of structural parameters of spiral chutes: The commonly used diameter specifications of industrial spiral chutes are 400mm, 600mm, 900mm, 1200mm, and 1500mm, and the transverse inclination angle of the chute surface is... Commonly used , , helix angle Usually .

[0026] (2) Critical upper limit When the angular velocity of the oscillation is too high, the additional inertial force on the slurry may exceed gravity, causing it to separate laterally along the tank surface. This can lead to the liquid film detaching from the tank bottom or splashing. The critical condition is that the maximum lateral component of the maximum additional inertial force equals the lateral component of gravity. The maximum value of the additional tangential inertial force is: ; The component of this force in the transverse direction of the groove is approximately ,in The lateral inclination angle of the tank surface is given by the lateral component of gravity. Stability requirements: ; when At critical stability, we have: ; Convert radian amplitude to angular amplitude: ; We can obtain: ; In a real spiral chute, the effective radial location where the maximum shear force is generated is approximately equal to the radius of the spiral chute. Take the eigenvalue Take the helix angle Considering the stability of industrial equipment, the safety factor is taken as... ,Pick ,have to: ; (3) Critical lower limit To achieve a significant sorting effect from the oscillation, the additional shear rate must reach at least a certain proportion of the base shear rate: in For the effective shear threshold, Within the range of 0.1 to 0.2, the oscillation can effectively enhance the Begno dispersion pressure without compromising the stability of the flow film, thus significantly improving the sorting efficiency. To determine the critical lower limit, we take ε = 0.1. Substituting the average additional shear rate, we find... , The tangential flow velocity is typically 1.0~2.0 m / s for industrial spiral chutes, and h is the film thickness, typically 2~10 mm. ; Convert radian amplitude to angular amplitude: ; We can obtain: Take the tangential flow velocity of the industrial spiral chute. , ,have to: ; (4) Determination of the upper frequency limit Since the upper and lower limits of the criticality are equal, we can conclude that: ; (5) Determination of the lower frequency limit The lower frequency limit is determined by the residence time of the slurry in the spiral chute and the minimum number of oscillations required for effective separation. The residence time of the slurry in the spiral chute is related to the equipment specifications. The spiral chute diameter range covered by this invention is 400mm~1500mm. The pitch-to-diameter ratio of industrial spiral chutes is usually 0.4~0.8. At the same rotation speed, the smaller diameter spiral chute has the shortest channel length, a relatively faster slurry flow rate, and a shorter residence time than the larger diameter spiral chute. Therefore, the lower frequency limit requirement is the most stringent. Using the smallest specification of 400mm diameter as the constraint benchmark for the lower frequency limit conforms to the common method of determining the applicable range based on boundary conditions in engineering design. Mineral particles need to undergo a sufficient number of oscillations in the spiral chute to form a stable separation zone. Based on the quantitative relationship between the cumulative effect of oscillation and the lateral migration distance of mineral particles, when the number of complete oscillation cycles reaches 3 or more, the cumulative migration distance of mineral particles on the trough surface is sufficient to cross the boundary between light and heavy minerals, and the separation effect tends to be stable; when there are fewer than 3 cycles, the migration distance is insufficient, and the mineral particles cannot complete effective stratification before discharge, and the separation effect tends to be close to the state without oscillation. Therefore, the minimum number of oscillations required for effective separation is determined to be 3. Existing literature, through tracer experiments, has measured an average residence time of approximately 7.5 seconds for a spiral chute with 5 turns, a diameter of 61.3 cm, and a pitch of 35.7 cm. For a small-diameter spiral chute of 400 mm, with a shorter channel length and faster slurry flow rate, the residence time is less than the measured value of the equipment in the literature; simulation results show that the slurry residence time is approximately 6 seconds.

[0027] Based on the above constraints, the lower frequency limit can be determined as follows: ; in: This represents the minimum number of oscillations, which is set to 3 here; This indicates the pause time, which is 6 seconds in this case.

[0028] If the frequency is below 0.5Hz, the number of complete oscillations will be less than 3, the cumulative migration distance will be insufficient, and a stable sorting band cannot be formed. Therefore, 0.5Hz is the minimum frequency required to satisfy the cumulative effect of 3 oscillations.

[0029] When a lower frequency limit of 0.5Hz can meet the constraints of the 400 mm specification, for larger diameter equipment, the spiral channel is longer and the slurry residence time is longer, allowing for more complete oscillations at this frequency, resulting in a more thorough separation effect. Therefore, 0.5Hz, determined based on the most demanding 400 mm small diameter sluice, is applicable to the entire specification range covered by this invention.

[0030] In summary, the lower frequency limit is determined as follows: ; (6) Specific boundaries of commonly used spiral chute specifications Example 1 See Figure 1-3 and Figure 6 This invention provides a technical solution for achieving reciprocating oscillation of a spiral chute using a rotary motor combined with a crank-rocker mechanism. The solution includes a spiral chute body 1, which is fixedly mounted on a rotating shaft 3. The rotating shaft 3 is mounted on a frame 6 via a bearing seat. The rotating shaft 3 can rotate relative to the frame 6 around its own axis, thereby driving the spiral chute body 1 to reciprocate around its central axis. A receiving trough 7 is located below the spiral chute body 1 to collect sorted minerals. A drive mechanism 2 is connected to the rotating shaft 3, driving the spiral chute body 1 to reciprocate around its central axis by reciprocating the rotating shaft 3. The central axis refers to the geometric central axis of the spiral chute body 1. The oscillation amplitude A is the maximum angle at which the spiral chute body 1 deflects from zero to one side, and the oscillation frequency f is the number of reciprocating oscillation cycles per second.

[0031] In one embodiment, the drive mechanism 2 includes a rotary motor 4, a crank-rocker mechanism 5, and a frequency converter 8. The crank-rocker mechanism 5 consists of a crank 51, a connecting rod 52, and an adjustable-length rocker arm 53. The output shaft of the rotary motor 4 is fixedly connected to one end of the crank 51, the other end of the crank 51 is hinged to one end of the connecting rod 52, the other end of the connecting rod 52 is hinged to one end of the adjustable-length rocker arm 53, and the other end of the adjustable-length rocker arm 53 is fixedly connected to the lower end of the rotating shaft 3. The frequency converter 8 is electrically connected to the rotary motor 4 and is used to adjust the speed of the rotary motor 4.

[0032] The working process of the above-described embodiment is as follows: When the rotary motor 4 rotates at a constant speed, the crank 51 performs circular motion, which drives the adjustable rod-length rocker arm 53 to oscillate back and forth through the connecting rod 52. The adjustable rod-length rocker arm 53 then drives the rotating shaft 3 to oscillate back and forth, thereby driving the spiral chute body 1 to oscillate periodically in both directions around the central axis. By adjusting the speed of the rotary motor 4 through the frequency converter 8, the oscillation frequency f of the spiral chute body 1 can be set; by adjusting the length of the adjustable rod-length rocker arm 53, the oscillation amplitude A of the spiral chute body 1 can be set. Since the adjustable rod-length rocker arm 53 is fixedly connected to the rotating shaft 3, changing the length of the rocker arm directly changes the oscillation angle of the rotating shaft 3, thereby achieving the adjustment of the oscillation amplitude. The combination of these two methods allows the oscillation parameters to be precisely set within the effective parameter range defined by the above-described constraint relationship.

[0033] Taking a spiral chute body 1 with a diameter of 400mm as an example, with R = 0.2m and the oscillation frequency f = 5Hz, the upper limit of the oscillation amplitude is calculated according to the formula for the upper and lower critical values ​​of the oscillation amplitude. Lower limit of swing amplitude Within this range, the swing amplitude A is selected as 4°, and the angular displacement curve is as follows. Mineral particles are loosely separated into layers on the surface of the spiral chute under the combined effects of their own gravity, centrifugal inertia, and the shear and vibration forces generated by the reciprocating oscillation of the spiral chute at specific amplitudes and frequencies. This gradually forms a concentrate zone, a middlings zone, and a tailings zone. The concentrate, middlings, and tailings are ultimately discharged from different outlets in the receiving trough 7. Experimental results show that, compared to a static spiral chute, the reciprocating spiral chute using the above oscillation parameters increases the concentrate recovery rate from 59.12% to 67.76% and the beneficiation efficiency from 59% to over 68%. This verifies that applying reciprocating oscillation within the constrained parameter region can effectively enhance the separation effect.

[0034] Example 2 Reference Figure 4Unlike Embodiment 1, in another embodiment, the drive mechanism 2 includes a hydraulic motor 9, a proportional valve 10, a hydraulic station 11, and a controller 12. The output shaft of the hydraulic motor 9 is fixedly connected to the rotating shaft 3, and the hydraulic motor 9 can directly drive the rotating shaft 3 to reciprocate. The oil inlet of the proportional valve 10 is connected to the hydraulic station 11, and the oil outlet of the proportional valve 10 is connected to the hydraulic motor 9. The hydraulic station 11 provides hydraulic oil to the hydraulic motor 9. The controller 12 is electrically connected to the electromagnet of the proportional valve 10. By sending a current signal or a PWM wave signal to the proportional valve 10, the controller controls the opening direction and opening area of ​​the valve core of the proportional valve 10, thereby controlling the flow rate and direction of the hydraulic oil flowing to the hydraulic motor 9, realizing the reciprocating rotation of the hydraulic motor 9. The reciprocating rotation of the hydraulic motor 9 is directly converted into the reciprocating oscillation of the rotating shaft 3, which in turn drives the spiral chute body 1 to reciprocate around the central axis. By adjusting the control signal parameters sent by the controller 12, the oscillation amplitude A and oscillation frequency f of the spiral chute body 1 can be set to satisfy the above-mentioned constraint relationship. The hydraulic motor 9 has a large output torque, making this implementation suitable for reciprocating oscillation drive scenarios in large and heavy-duty spiral chutes. Under the combined action of gravity, centrifugal inertia, and shear and vibration forces generated by reciprocating oscillation on the surface of the spiral chute, mineral particles are loosely separated into layers, forming concentrate belts, middlings belts, and tailings belts, which are discharged from different discharge ports of the receiving trough 7, respectively. The separation effect is similar to that of Example 1.

[0035] Example 3 Reference Figure 5 Unlike Embodiments 1 and 2, in another embodiment, the drive mechanism 2 includes a servo motor 13, a servo driver 14, a reducer 15, a coupling 16, and a control unit 17. The output shaft of the servo motor 13 is fixedly connected to the reducer 15, and the output shaft of the reducer 15 is fixedly connected to the rotating shaft 3 via the coupling 16, thereby transmitting the rotational motion of the servo motor 13 to the rotating shaft 3 after reduction. The servo driver 14 is electrically connected to the servo motor 13 and is used to output drive signals to the servo motor 13. The servo motor 13 is equipped with an encoder, which is electrically connected to the servo driver 14 and is used to provide real-time feedback to the servo driver 14 on the actual angular displacement of the servo motor 13, which is the actual angular displacement of the rotating shaft 3 and the spiral chute body 1. The control unit 17 is a programmable logic controller (PLC) with a built-in swing motion control program, and the control unit 17 is electrically connected to the servo driver 14. The servo driver 14 receives pulse commands from the control unit 17 and, combined with the actual angular displacement signal fed back by the encoder, forms a closed-loop position control, driving the servo motor 13 to periodically rotate forward and backward through an inverter circuit.

[0036] The working process of the above implementation method is as follows: The set swing amplitude A and swing frequency f are input to the control unit 17 through the human-machine interface. The control unit 17 calculates the swing curve and speed curve of the servo motor 13 according to the set parameters, generates corresponding pulse commands and sends them to the servo driver 14. The servo driver 14 combines the actual angular displacement signal fed back by the encoder to form a closed-loop position control, driving the servo motor 13 to complete the periodic forward and reverse rotation. Within half a cycle, the servo motor 13 rotates from the zero position forward to the swing amplitude angle position A, then rotates in the reverse direction to the zero position and continues to rotate to -A, and then returns to the zero position, completing a complete periodic swing, thereby driving the spiral chute body 1 to swing back and forth within the swing amplitude range of A to -A. Since the encoder feeds back the actual angular displacement of the rotating shaft 3 in real time, the closed-loop position control makes the control accuracy of the swing amplitude and swing frequency higher, which is suitable for application scenarios with high requirements for the accuracy of sorting parameters. Under the action of the composite force field, the mineral particles are loosely layered to form concentrate belt, middlings belt and tailings belt, which are discharged from different discharge ports of the receiving trough 7, and the sorting effect is similar to that of Example 1.

[0037] Reference Figure 6 The working process of the spiral chute reciprocating oscillation separation method is described below. First, based on the radius R of the spiral chute body 1 and according to the above-mentioned constraints, the oscillation amplitude A and oscillation frequency f of the spiral chute body 1 are set under the premise of satisfying the oscillation frequency f. Subsequently, the drive mechanism 2 drives the spiral chute body 1 to reciprocate around the central axis at the set oscillation amplitude A and oscillation frequency f. Under the continuous reciprocating oscillation state of the spiral chute body 1, the slurry is continuously fed from the feed end of the spiral chute body 1. While the slurry is making spiral rotational motion on the surface of the spiral chute, it is periodically disturbed by the additional tangential force generated by the reciprocating oscillation. Under the combined action of gravity, centrifugal force, friction, and the shear force and vibration force generated by the reciprocating oscillation, the mineral particles are fully loosened and stratified. Mineral particles of different specific gravities and particle sizes eventually form stable zones on the spiral chute surface: heavy mineral particles form a concentrate zone at the inner edge, medium specific gravities mineral particles form a middlings zone, and light mineral particles form a tailings zone at the outer edge. After the slurry flows to the end of the spiral chute, it is separated into concentrate discharge outlets, middlings discharge outlets, and tailings discharge outlets in receiving trough 7, achieving effective mineral separation. Because the reciprocating oscillation employs a periodic alternating forward and reverse motion, the slurry is subjected to symmetrical periodic disturbances under the alternating forward and reverse tangential forces, effectively breaking up mineral particle clusters and avoiding the problem of mineral accumulation on the inner side caused by unidirectional rotation.

[0038] The embodiments disclosed in this invention are preferred embodiments, but are not limited thereto. Those skilled in the art can easily understand the spirit of this invention based on the above embodiments and make different extensions and variations, but as long as they do not depart from the spirit of this invention, they are all within the protection scope of this invention.

Claims

1. A reciprocating oscillating spiral chute, comprising a spiral chute body (1) and a drive mechanism (2); characterized in that, The drive mechanism (2) is connected to the spiral chute body (1) for transmission, driving the spiral chute body (1) to reciprocate around the central axis with an amplitude A and a frequency f; the frequency f satisfies The swing amplitude A and the swing frequency f satisfy the following condition: R is the radius of the spiral chute body (1), and .

2. The reciprocating oscillating spiral chute according to claim 1, characterized in that, The oscillation frequency f satisfies The radius R is .

3. The reciprocating oscillating spiral chute according to claim 1, characterized in that, The main body of the spiral chute (1) is a single-head spiral chute or a multi-head spiral chute.

4. The reciprocating oscillating spiral chute according to claim 1, characterized in that, The spiral chute body (1) is fixedly installed on the rotating shaft (3), the rotating shaft (3) is installed on the frame (6), the driving mechanism (2) is connected to the rotating shaft (3) for transmission, and the spiral chute body (1) is driven to swing back and forth around the central axis by driving the rotating shaft (3) to swing back and forth.

5. The reciprocating oscillating spiral chute according to claim 4, characterized in that, The drive mechanism (2) includes a rotary motor (4) and a crank-rocker mechanism (5). The crank-rocker mechanism (5) includes a crank (51), a connecting rod (52), and a rocker arm. The output shaft of the rotary motor (4) is fixedly connected to one end of the crank (51). The other end of the crank (51) is hinged to one end of the connecting rod (52). The other end of the connecting rod (52) is hinged to one end of the rocker arm. The other end of the rocker arm is fixedly connected to the rotating shaft (3).

6. The reciprocating oscillating spiral chute according to claim 5, characterized in that, The rocker arm is an adjustable length rocker arm (53), and the swing amplitude A is set by adjusting the length of the rocker arm; the rotary motor (4) adjusts the speed through the frequency converter (8) to set the swing frequency f.

7. The reciprocating oscillating spiral chute according to claim 4, characterized in that, The drive mechanism (2) includes a hydraulic motor (9), a proportional valve (10), a hydraulic station (11), and a controller (12). The output shaft of the hydraulic motor (9) is fixedly connected to the rotating shaft (3). The oil inlet of the proportional valve (10) is connected to the hydraulic station (11), and the oil outlet of the proportional valve (10) is connected to the hydraulic motor (9). The controller (12) is electrically connected to the proportional valve (10). By sending a control signal to the proportional valve (10), the controller controls the valve core opening direction and opening area to set the swing amplitude A and the swing frequency f.

8. The reciprocating oscillating spiral chute according to claim 4, characterized in that, The drive mechanism (2) includes a servo motor (13), a servo driver (14), a reducer (15), a coupling (16), and a control unit (17). The output shaft of the servo motor (13) is fixedly connected to the reducer (15), and the output shaft of the reducer (15) is fixedly connected to the rotating shaft (3) through the coupling (16). The servo driver (14) is electrically connected to the servo motor (13) and is used to output drive signals to the servo motor (13). The servo motor (13) is equipped with an encoder, which is electrically connected to the servo driver (14) and is used to feed back the rotation position signal of the servo motor (13) to the servo driver (14). The control unit (17) is electrically connected to the servo driver (14) and performs closed-loop position control on the servo motor (13) through the servo driver (14) to drive the rotating shaft (3) to swing back and forth.

9. A sorting method for a reciprocating oscillating spiral chute as described in any one of claims 1-8, characterized in that, Includes the following steps: (1) Set the swing amplitude A and swing frequency f of the spiral chute body (1), wherein the swing frequency f satisfies The swing amplitude A and the swing frequency f satisfy the following condition: , where R is the radius of the spiral chute body (1); (2) Drive the spiral chute body (1) to oscillate back and forth around the central axis with the oscillation amplitude A and the oscillation frequency f; (3) The slurry is continuously fed from the feed end of the spiral chute body (1). Under the combined action of gravity, centrifugal force, friction and shear force and vibration generated by reciprocating swing, the mineral particles are loosely separated into layers, forming stable zones on the spiral chute surface, and are discharged through the ore blocks to different discharge outlets.

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