An adaptive control method for sandstone waste screening stuck based on vibration load feedback

Abstract

The application discloses a self-adaptive control method for sandstone waste material screening and unjamming based on vibration load feedback, which is applied to a screening device comprising a vibrating frame, a plurality of screen rods and a driving and guiding structure. An operation feedback signal of the device is acquired to determine whether unjamming is needed; the driving and guiding structure is controlled to drive the free end of the screen rod to reciprocate within an unjamming stroke, so that the interval between adjacent screen rods periodically changes; the timing of the reciprocation of the free end is acquired as an active excitation reference, and the vibrating frame is controlled to keep vibrating; the load feedback of the vibrating frame within each phase interval is acquired to determine an actual synchronous vibration load response; a structure response benchmark in a non-jamming state is acquired to determine a residual jamming response; according to the change of the residual jamming response within a continuous active excitation period, the current unjamming stroke is controlled to be kept, the next unjamming stroke is entered or the unjamming is terminated.

Description

Technical Field

[0001] This invention relates to the field of sand and gravel recycling technology, and specifically to an adaptive control method for a sand and gravel waste screening and decomposition card based on vibration load feedback. Background Technology

[0002] Sand and gravel waste generated during sand and gravel production, construction, and concrete processing typically includes sand, gravel, soil, and irregularly shaped lumps. To recover aggregates that meet particle size requirements, bar screens are commonly used to screen the waste. During screening, a vibrating frame drives multiple screen bars to vibrate, causing materials that meet the particle size requirements to fall through the gaps between adjacent screen bars, while larger particles move along the screen surface to the discharge position. When stones become wedged between adjacent screen bars, they can be removed by moving a cleaning mechanism, adjusting the relative positions of the screen bars, or changing the screening conditions.

[0003] In actual operation, the shape, embedding direction, surface roughness, and contact state between the stones and the screen rods vary. When the cleaning mechanism passes the location of the stones, some stones may detach from the screen rod under the thrust, some stones may only undergo local displacement, and others may remain in contact and clamped with the screen rod after the cleaning mechanism passes. Therefore, it is difficult to accurately reflect the actual jamming state between adjacent screen rods based solely on whether the cleaning mechanism passes the location of the stones, whether the drive mechanism completes the preset stroke, or whether the drive load changes once. If a fixed stroke or a fixed number of cleaning actions are used without confirming the jamming state, insufficient cleaning stroke, continuous application of ineffective cleaning actions, or repeated application of deformation loads on the screen rods may occur.

[0004] Furthermore, when the screen bar undergoes relative displacement during the cleaning process, the elastic deformation of the screen bar itself, the friction between transmission components, the contact between guide components, and the disturbance of residual material all affect the vibration load. Existing cleaning methods typically do not distinguish between load changes caused by the inherent structure of the device and additional load changes caused by the continuous clamping of stones, nor do they establish a correspondence between changes in the jamming state and subsequent cleaning actions, making it difficult to adapt the cleaning process for stones with different degrees of embedding to actual working conditions. Summary of the Invention

[0005] The main objective of this invention is to provide an adaptive control method for the decomposition card of sand and gravel waste screen based on vibration load feedback, so as to solve the technical problem of how to reliably determine the change of jamming state between adjacent screen bars when the cleaning mechanism passes through the area where the jammed stone is located but the jammed stone does not necessarily disengage, and to make the subsequent cleaning action adapt to the actual jamming state.

[0006] To achieve the above objectives, this invention provides an adaptive control method for a sand and gravel waste screening decomposition card based on vibration load feedback, applied to a variable-gap unclogging screening device for sand and gravel waste recycling. The device includes a vibrating frame, multiple screen rods, and a drive and guide structure. Each screen rod includes a free end and a fixed end. The method comprises the following steps: S1. Obtain the operation feedback signal of the device and determine whether the device needs to be unlocked; S2. When it is necessary to unblock, the drive guide structure is controlled to drive the free ends of each screen rod to reciprocate within the unblocking stroke, so as to periodically increase the distance between adjacent screen rods. S3. Obtain the timing sequence of the drive guide structure driving the reciprocating motion of the free end, use the timing sequence as an active excitation reference, and control the vibration frame to maintain vibration; S4. Obtain the load feedback of the drive source of the vibration frame in each phase interval corresponding to the active excitation reference, and determine the actual synchronous vibration load response. S5. Obtain the structural response benchmark corresponding to the active excitation reference under the unobstructed state, and determine the residual obstruction response based on the actual synchronous vibration load response and the structural response benchmark. S6. Obtain the changes in the residual jamming response within multiple consecutive active excitation cycles, and control the drive guide structure to maintain the current unblocking stroke, enter the next unblocking stroke, or terminate the unblocking process based on the changes in the residual jamming response.

[0007] Furthermore, the drive guide structure includes a drive assembly, a moving plate, and a plurality of cleaning blocks disposed on the moving plate and slidably engaged with each of the screen rods. Each cleaning block is provided with a wedge-shaped thin plate, the tip of which faces the free end of the screen rod. Before step S2, the following steps are also included: The drive assembly is controlled to drive the moving plate toward the free end of the screen rod along the extension direction of the screen rod, so that the moving plate drives each of the cleaning blocks to move along the corresponding screen rod; The wedge-shaped thin plates are used to clean the adhering substances on the surface of the corresponding screen rods, and each wedge-shaped thin plate is brought into contact with the stuck stone located between adjacent screen rods to apply a force to the stuck stone along the extension direction of the screen rod; After the cleaning block passes through the area where the stuck stone is located, it is not determined from the passing state of the cleaning block or the change in the single operation current of the drive component that the stuck stone has been removed from the adjacent screen bar.

[0008] More preferably, the following steps are included before step S2: The operating current, duration, preset allowable overload current threshold, preset duration, and preset backoff distance of the drive component are obtained. When the operating current exceeds the preset allowable overload current threshold and the duration reaches the preset duration, the drive component is controlled to stop operating, or the drive component is controlled to drive the moving plate to move the preset clearance distance in a direction opposite to the extension direction of the screen rod. The operating current is used only to determine the overload protection action of the drive component.

[0009] Further preferably, the device further includes a support structure, a release structure, a horizontal plate, multiple support rings, a push rod, a tension spring, a guide plate, a slide rod, and a fixed column. Each screen rod has a slot at its free end, the slide rod is slidably disposed within the slot, the fixed column is disposed at the extended end of the slide rod, the support rings are respectively sleeved on each slide rod, the push rod is disposed on the moving plate, the tension spring is connected between the horizontal plate and the vibrating frame, and the guide plate has guide grooves corresponding to each fixed column, the guide grooves including a first diagnostic effective guide area; Step S2 specifically includes the following steps: The drive assembly is controlled to drive the moving plate to move, so that the push rod pushes the horizontal plate from the support position to the release position, so that each support ring disengages from the corresponding slide rod; After each of the support rings disengages from the corresponding slide bar, the moving plate is controlled to move, so that each of the fixed columns enters the first diagnostic effective guide area of ​​the corresponding guide groove, so that the free ends of each of the screen rods produce different lateral elastic offsets and form a first diagnostic expansion gap; The position of the movable plate when each of the fixed columns is located in the corresponding first diagnostic effective guide area is determined as the first diagnostic position; The drive assembly is controlled to drive the moving plate to reciprocate between the first diagnostic position and the first partial reset position. The first partial reset position is located on the travel distance of the moving plate from the first diagnostic position back to the initial position, and each of the fixed posts remains in the corresponding guide groove.

[0010] More preferably, the timing sequence in step S3 includes a recurring gap widening phase and a partial reset phase; step S4 specifically includes the following steps: The load feedback of the drive source is segmented according to the widening phase and the partial reset phase; Obtain the load feedback of the drive source within each expansion phase and each partial reset phase; The actual synchronous vibration load response is determined based on the differences between the load feedback in each expansion phase and each partial reset phase.

[0011] More preferably, the step S5 of obtaining the structural response benchmark specifically includes: Obtain the load feedback of the drive source under the same vibration parameters, same moving plate trajectory and same unblocking stroke as the active excitation reference, in a state where there are no stuck stones between adjacent screen bars; The structural response benchmark is determined based on the load feedback under the unobstructed state; wherein, the load feedback under the unobstructed state is obtained during the equipment debugging phase, during the cleaning cycle confirming that there are no stuck stones between adjacent screen bars, or in a stable state after one unblocking. The residual jamming response is determined based on the difference between the actual synchronous vibration load response and the structural response benchmark.

[0012] More preferably, step S6 specifically includes the following steps: Get the preset card unlocking completion range, preset number of consecutive cycles, and preset verification duration; When the residual jamming response is within the preset unblocking completion range within the preset number of consecutive active excitation cycles, the drive guide structure is controlled to keep the moving plate in the first partial reset position, and the vibration frame is controlled to maintain vibration. Obtain the load feedback of the drive source within the preset verification time, determine the actual synchronous vibration load response of the verification stage based on the load feedback, and re-determine the residual jamming response based on the actual synchronous vibration load response of the verification stage and the structural response benchmark. When the redefined residual jamming response is within the preset unblocking completion range, the drive guide structure is controlled to terminate the unblocking process; When the redefined residual jamming response is outside the preset unblocking completion range, the drive guide structure is controlled to maintain the current unblocking stroke and continue to drive the free ends of each screen rod to reciprocate.

[0013] More preferably, the card unlocking process includes multiple tiered card unlocking processes, and further includes the following steps: Obtain the preset maximum number of pulses and the preset maximum level of card unlocking stroke corresponding to each of the aforementioned graded card unlocking strokes; When the current graded unblocking stroke is not the preset maximum graded unblocking stroke, and the residual jamming response is still outside the preset unblocking completion range after reaching the preset maximum number of pulses corresponding to the current graded unblocking stroke, the drive guide structure is controlled to drive the free ends of each screen rod into the next graded unblocking stroke, and the structural response benchmark corresponding to the next graded unblocking stroke is obtained or called. When the current graded card unblocking stroke is the preset maximum graded card unblocking stroke, and the residual card resistance response is still outside the preset card unblocking completion range after reaching the preset maximum number of pulses corresponding to the current graded card unblocking stroke, the drive guide structure is controlled to end the gap widening action, the residual card resistance response and the current graded card unblocking stroke of this cleaning cycle are recorded, and a maintenance prompt is output.

[0014] More preferably, after step S6 controls the termination of card unlocking, the following steps are also included: Obtain the preset reset vibration state; The drive assembly is controlled to drive the moving plate to the initial position, so that each of the fixed columns exits the effective guide area of ​​the corresponding guide groove, and so that each of the screen rods returns to the initial arrangement position under the elastic action; After each of the screen rods returns to its initial arrangement position, the vibrating frame is controlled to pause vibration or adjust to the preset reset vibration state; The movable plate is controlled to continue moving to the initial position, so that the push rod releases the push on the horizontal plate and the tension spring drives the horizontal plate back to the support position, so that each support ring is re-sleeved onto the corresponding slide rod; After each of the support rings is re-sleeved onto the corresponding slide bar, the vibrating frame is controlled to restore normal screening vibration parameters.

[0015] Furthermore, step S1 specifically includes the following steps: Get the preset cleaning interval, preset screening efficiency operating range, and preset discharge time; Obtain the current screening runtime, screening efficiency information, and cleaning instructions issued by the operator since the last cleaning was completed; When the current screening runtime reaches the preset cleaning interval, the screening efficiency information indicates that the current screening efficiency is outside the preset screening efficiency operating range, or the cleaning command is obtained, it is determined that the device needs to be unlocked. After determining that the device needs to be unblocked, stop feeding sand and gravel waste into the feed end of the vibrating frame, and control the vibrating frame to maintain vibration until the preset discharge time is reached, so as to discharge the material to be cleaned.

[0016] Compared with the prior art, the present invention has the following beneficial effects: This invention controls the reciprocating motion of the free end of the screen rod within the unblocking stroke, causing the distance between adjacent screen rods to change according to a known time sequence. While maintaining vibration on the vibrating frame, the changes in the contact, clamping, and friction states between the stuck stone and the screen rod are converted into a vibration load response corresponding to the time sequence. Furthermore, the structural response benchmark under unblocked conditions eliminates the influence of elastic deformation of the screen rod and the inherent load generated by the device's operation. The residual jamming response, characterizing the degree of residual jamming between adjacent screen rods, is determined from the actual synchronous vibration load response. Therefore, whether the cleaning mechanism has passed through the area where the stuck stone is located is no longer used as a basis for judging the stuck stone's state. Based on the changes in the residual jamming response within a continuous active excitation cycle, the current unblocking stroke can be maintained, the unblocking stroke adjusted, or the unblocking terminated according to the actual jamming state, avoiding ineffective actions and unnecessary repeated deformation of the screen rod caused by performing cleaning only according to a preset stroke or preset number of times. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the overall structure of a variable gap unclogging screening device for sand and gravel waste recycling according to an embodiment of the present invention; Figure 2 This is a side cross-sectional view of a variable gap unclogging screening device for sand and gravel waste recycling according to an embodiment of the present invention; Figure 3 This is a partial structural diagram of the vibrating frame in a variable-gap unclogging screening device for sand and gravel waste recycling according to an embodiment of the present invention. Figure 4 This is a schematic diagram of the drive component in a variable-gap unclogging screening device for sand and gravel waste recycling according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the internal structure of the screen rod in a variable gap unclogging screening device for sand and gravel waste recycling according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the arrangement of multiple screen rods in a variable gap unclogging screening device for sand and gravel waste recycling according to an embodiment of the present invention. Figure 7 This is a schematic diagram of the supporting structure and guiding components in a variable gap unclogging screening device for sand and gravel waste recycling according to an embodiment of the present invention; Figure 8 This is a flowchart illustrating an adaptive control method for a sand and gravel waste screening decomposition card based on vibration load feedback, according to one embodiment of the present invention.

[0019] Explanation of reference numerals in the attached figures: 1. Frame; 2. Vibrating frame; 21. Baffle; 3. Fixing plate; 41. Screen rod; 42. Grooving; 43. Slide rod; 44. Fixing column; 45. Lead screw; 46. Moving seat; 47. Motor; 51. Moving plate; 52. Cleaning block; 53. Push rod; 54. Slide rail; 61. Guide plate; 62. Guide groove; 71. Horizontal plate; 72. Support ring; 73. Guide rod; 74. Tension spring.

[0020] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0021] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0022] 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 a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0023] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0024] Furthermore, the use of terms such as "first" and "second" in this invention is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention.

[0025] The sand and gravel waste in the following embodiments includes sand, soil, aggregate with a particle size smaller than the spacing of the screen bars 41, and irregularly shaped stones. The initial spacing of the screen bars 41 is 30 mm. The screen bars 41 are made of spring steel, have a diameter of 16 mm, and an effective length of 800 mm from the fixed plate 3 to the free end. The above-mentioned materials, diameter, and effective length are determined based on the working conditions that the screen bars 41 need to withstand the impact of falling sand and gravel, generate recoverable elastic displacement during unclogging, and maintain a stable arrangement during normal screening.

[0026] Please see Figures 1 to 7 This embodiment provides a variable gap unblocking screening device for sand and gravel waste recycling, including a vibrating frame 2, a fixed plate 3, multiple screen rods 41 with elastic reset capability, a support structure, a release structure, and a drive guide structure. The fixed plate 3 is fixedly connected to the vibrating frame 2.

[0027] In this embodiment, the vibrating frame 2 is mounted on the frame 1, and the frame 1 is equipped with a drive source for driving the vibrating frame 2 to vibrate. Sand and gravel waste enters from the feed end of the frame 1, is screened by the screen rods 41 on the vibrating frame 2, and is discharged from the discharge end of the frame 1. A fixing plate 3 is fixed to one end of the vibrating frame 2, and multiple screen rods 41 are arranged at intervals along the length of the fixing plate 3. Each screen rod 41 includes a fixed end and a free end; the fixed end is fixedly connected to the fixing plate 3, and the free end extends towards the end of the vibrating frame 2 away from the fixing plate 3.

[0028] Under normal screening conditions, the screen rods 41 vibrate with the vibrating frame 2. Materials with a particle size smaller than the initial screen rod spacing fall between adjacent screen rods 41, while other materials are conveyed along the extension direction of the screen rods 41. The screen rods 41 are made of spring steel and can return to their initial arrangement position after the external force is removed. This embodiment enables the screen rods 41 to maintain the load-bearing capacity required to maintain screening function when subjected to the impact and vibration loads of sand and gravel waste, and provides a structural basis for elastic reset during subsequent unblocking processes.

[0029] More specifically, the fixed end of the screen rod 41 is fixed to the fixed plate 3 by welding or bolting, while the free end of the screen rod 41 is not rigidly connected to the fixed plate 3. Taking a screen rod 41 with a diameter of 16mm, an effective length of 800mm, and an initial screen rod spacing of 30mm as an example, the lateral displacement of the free end of the screen rod 41 during the unblocking process is constrained by the elastic limit of the material, with the maximum lateral displacement limited to no more than 18mm. This value is determined based on the allowable stress of the spring steel screen rod, the bending stress of the fixed end, and the repeated service life, ensuring that the screen rod 41 maintains recoverable elastic deformation under the corresponding unblocking stroke. Through the above method, the screen rod 41 can have the lateral elastic displacement capability required to release the stones during the unblocking state, while avoiding plastic deformation.

[0030] The support structure, release structure, and drive guide structure are all mounted on the vibration frame 2. The support structure moves between the support position and the release position. When the support structure is in the support position, it cooperates with the free end to limit the lateral elastic displacement of the free end.

[0031] In this embodiment, the support structure applies lateral constraints to the free ends of each screen rod 41 under normal screening conditions, maintaining an initial screen rod spacing of 30mm between adjacent screen rods 41. When the support structure is in the released position, no lateral constraints are applied to the free ends of the screen rods 41, allowing the free ends of the screen rods 41 to undergo lateral elastic displacement under the action of the drive guide structure. This results in different constraint conditions for the screen rods 41 between the normal screening state and the unblocking state, preventing disorderly lateral oscillation of the screen rods 41 during the screening process.

[0032] The release structure works in conjunction with the support structure to drive the support structure from the support position to the release position, causing the support structure to detach from each free end.

[0033] In this embodiment, the travel distance of the release structure corresponds to the movement distance of the support structure from the support position to the release position. The release position is determined by the fact that the support structure no longer restricts the lateral elastic displacement of the free end of the screen rod 41. In this embodiment, the constraint of the support structure is removed before the lateral elastic displacement of the screen rod 41 occurs, thus avoiding interference between the support structure and the free end of the screen rod 41.

[0034] The drive guide structure is connected to each free end so that when the support structure is in the released position, it drives each free end to produce different lateral elastic offsets, thereby increasing the distance between at least some of the adjacent screen rods 41.

[0035] In this embodiment, the drive guide structure applies a combined action along and perpendicular to the extension direction of each screen rod 41 to its free end, causing different screen rods 41 to have different lateral offset directions or offset distances. The difference in lateral offset between adjacent screen rods 41 expands the initial screen rod spacing of 30mm between adjacent screen rods 41 to the screen rod spacing corresponding to the unblocking stroke. In this way, a change in the spacing between adjacent screen rods 41 can be formed after the support structure is removed, causing stones wedged between adjacent screen rods 41 to lose their continuous clamping condition.

[0036] This embodiment constrains the free ends of the screen rods 41 at the support position using a support structure, ensuring a relatively stable arrangement of the screen rods 41 under normal screening conditions and reducing the impact of material impact and vibration on the screening gap. During the unblocking process, the structure is released, disengaging the support structure from the free ends of the screen rods 41. The driving guide structure then causes different lateral elastic offsets at the free ends of the screen rods 41, resulting in an expanded gap between at least some adjacent screen rods 41, weakening the lateral clamping and friction constraints on the wedged stones. The elastic restoring capability of the free ends of the screen rods 41 allows the screening gap to return to the normal screening state after unblocking. This device does not require continuously maintaining a variable screening gap during normal screening; instead, it switches the constraint and displacement states of the free ends of the screen rods 41 during unblocking, allowing the stability of the screening gap and the required spacing for stone removal to be achieved separately under different operating conditions, reducing localized material accumulation caused by stuck stones and the frequency of downtime for cleaning.

[0037] In one embodiment, the free end of the screen rod 41 is provided with a slot 42 along the extension direction of the screen rod 41, and a slide rod 43 is slidably arranged in the slot 42. The slide rod 43 cooperates with the slot 42, and a fixing post 44 is fixedly provided at the extended end of the slide rod 43.

[0038] The slot 42 extends along the centerline of the screen rod 41, and the outer circumferential surface of the slide rod 43 forms a sliding fit with the wall of the slot 42. The remaining fit length of the slide rod 43 within the slot 42 is not less than twice the diameter of the slide rod 43, so that the slide rod 43 maintains guiding stability in the extended state. The fixing post 44 is fixed to the end of the slide rod 43 extending out of the slot 42 and forms a force transmission connection with the slide rod 43. The fixing post 44 transmits the force along the extension direction of the screen rod 41 to the slide rod 43, and the slide rod 43 transmits the lateral displacement to the free end of the screen rod 41, thereby causing the free end of the screen rod 41 to produce a lateral elastic offset in a controlled state.

[0039] In one embodiment, the drive guide structure includes a movable plate 51, a guide assembly, and a drive assembly. The movable plate 51 is mounted on the vibrating frame 2 and can move along the extension direction of the screen rod 41. The movable plate 51 is provided with cleaning blocks 52 that slide and cooperate with each screen rod 41 respectively. The drive assembly is connected to the movable plate 51 in a transmission manner to drive the movable plate 51 to move the cleaning blocks 52 along the screen rod 41. After the movable plate 51 abuts against the fixed column 44, it pushes the slide rod 43 to slide out of the slot 42. The guide assembly is located in front of the slide rod 43 in the extension direction. When the slide rod 43 extends, the fixed column 44 cooperates with the guide assembly to drive each slide rod 43 to produce different lateral elastic offsets.

[0040] In this embodiment, the moving plate 51 is arranged perpendicular to the extending direction of the screen rod 41, and multiple cleaning blocks 52 are fixed on the moving plate 51 and respectively fitted onto the corresponding screen rod 41. When the moving plate 51 moves toward the free end of the screen rod 41, the cleaning blocks 52 move along the outer surface of the screen rod 41, and after moving to the position of the fixed column 44, push the fixed column 44, causing the slide rod 43 to move along the slot 42 toward the guide assembly. The contact surface between the cleaning block 52 and the fixed column 44 can be rounded to reduce local stress during continuous contact. In this embodiment, multiple screen rods 41 are cleaned and force transmitted simultaneously by a single moving plate 51, reducing the structural complexity of setting separate driving components for each screen rod 41.

[0041] In this embodiment, a driving assembly drives a moving plate 51 to move along the extension direction of the screen rod 41, causing multiple cleaning blocks 52 fixed on the moving plate 51 to move synchronously along their corresponding screen rods 41. This enables simultaneous cleaning of multiple screen rods 41, and ensures that each cleaning block 52 abuts against its corresponding fixed post 44, transmitting the movement of the moving plate 51 to each sliding rod 43. When the fixed post 44 engages with the guide assembly, the sliding rod 43 extends from the slot 42 and transmits the lateral displacement generated by the guide assembly to the free end of the screen rod 41. The moving plate 51 is positioned perpendicular to the extension direction of the screen rod 41, ensuring that the movement stroke of each cleaning block 52 remains consistent. The rounded transition between the cleaning block 52 and the fixed post 44 reduces local stress during continuous contact, thereby maintaining a stable force transmission process and reducing the need for separate driving components for each screen rod 41.

[0042] In this embodiment, the guide assembly further includes a guide plate 61, on which a plurality of guide grooves 62 are provided. The guide plate 61 is fixed on the vibration frame 2 and is positioned in front of the extension direction of the slide rod 43. When the slide rod 43 extends, each guide groove 62 engages with the corresponding fixed post 44. The centerline spacing between adjacent guide grooves 62 increases along the direction in which the fixed post 44 enters the guide groove 62, forming a radial shape, so that when each fixed post 44 moves along the corresponding guide groove 62, it drives each slide rod 43 to produce different lateral displacements.

[0043] Specifically, the guide plate 61 is fixed to the end of the vibrating frame 2 away from the fixed plate 3, and the opening of each guide groove 62 is opposite to the initial position of the corresponding fixed column 44. The centerline distance between adjacent guide grooves 62 gradually increases from the opening to the bottom of the groove. After the fixed column 44 enters the guide groove 62 under the force applied by the moving plate 51, the groove wall of the guide groove 62 applies a lateral guiding effect to the fixed column 44, causing the fixed columns 44 located in different guide grooves 62 to produce different lateral displacements, thereby causing different lateral elastic offsets at the free ends of the corresponding screen rods 41. In this embodiment, the linear movement of the moving plate 51 is converted into differentiated lateral elastic offsets at the free ends of multiple screen rods 41, avoiding the situation where multiple screen rods 41 move in the same direction as a whole without changing the spacing between the screen rods.

[0044] In this embodiment, the guide plate 61 is fixed to the end of the vibrating frame 2 away from the fixed plate 3, and the center line spacing of adjacent guide grooves 62 is increased along the direction in which the fixed column 44 enters the guide groove 62. When the fixed column 44 moves along the corresponding guide groove 62 under the action of the moving plate 51, it is subjected to lateral guiding action in different directions, and then the free ends of each screen rod 41 are subjected to different lateral elastic offsets via the slide rod 43. The linear movement of the moving plate 51 is thus converted into a change in the spacing between adjacent screen rods 41, which weakens the clamping effect on the wedge between adjacent screen rods 41, and restores the initial arrangement of screen rods 41 by the elastic reset of the free ends of screen rods 41 after the fixed column 44 exits the guide groove 62.

[0045] In one embodiment, the cleaning block 52 has a channel that engages with and passes through the screen rod 41. The side of the cleaning block 52 facing the fixing post 44 is provided with a wedge-shaped sheet around the screen rod 41. The tip of the wedge-shaped sheet faces the fixing post 44, and the top of the wedge-shaped sheet is flush with the top of the cleaning block 52 and forms a transition.

[0046] The inner wall of the channel maintains a sliding gap with the outer surface of the screen rod 41, allowing the cleaning block 52 to move along the extension direction of the screen rod 41. The wedge-shaped sheet gradually thins from the end connected to the cleaning block 52 towards the tip, and the top of the wedge-shaped sheet is smoothly connected to the top of the cleaning block 52, avoiding the formation of steps that obstruct stones during movement. The thickness of the wedge-shaped sheet is determined by the initial spacing of the screen rods and the shape of the stone to be processed. In this embodiment, the thickness at the tip is 2 mm, and the thickness at the root is 6 mm. This thickness range is determined based on the requirement that the wedge-shaped sheet can enter between adjacent screen rods 41 and withstand the contact force of the stone. This embodiment can remove dirt and fine particles from the surface of the screen rod 41, and when the cleaning block 52 encounters a stuck stone, it applies a force to the stuck stone along the extension direction of the screen rod 41. When the stuck stone is still held by adjacent screen rods 41, the wedge-shaped sheet can squeeze through along the surface of the stuck stone or the contact area between the stuck stone and the screen rod 41, allowing the cleaning block 52 to complete its movement. When the stuck stone is clamped by the adjacent screen rod 41 and cannot move along the extension direction of the screen rod 41, the tip of the wedge-shaped thin plate enters the contact area between the stuck stone and the screen rod 41. The wedge-shaped thin plate slides along the surface of the stuck stone or the surface of the screen rod 41, causing the cleaning block 52 to continue moving towards the fixed column 44. At this time, the passing of the cleaning block 52 through the area where the stuck stone is located does not change the fact that the stuck stone may still contact the adjacent screen rod 41. Therefore, the passing state of the cleaning block 52 is not used as the basis for determining the termination of the unblocking.

[0047] In one embodiment, the support structure includes a horizontal plate 71, multiple support rings 72, two guide rods 73, and a tension spring 74. The two guide rods 73 are fixed to both sides of the vibrating frame 2. The horizontal plate 71 is slidably sleeved on the two guide rods 73. The multiple support rings 72 are fixed to the horizontal plate 71. The support rings 72 and the screen rods 41 correspond one-to-one. The support rings 72 are respectively sleeved on their respective slide rods 43. The tension spring 74 is connected between the horizontal plate 71 and the vibrating frame 2 to drive the horizontal plate 71 to remain in the support position.

[0048] Specifically, in this embodiment, the horizontal plate 71 moves along the guide rod 73, and multiple support rings 72 are arranged on the horizontal plate 71. When the horizontal plate 71 is in the support position, the axis of the annular hole of each support ring 72 is opposite to the axis of the corresponding slide rod 43, and each support ring 72 is sleeved on the corresponding slide rod 43. The support rings 72 form a lateral limit on the slide rod 43, so that the free end of the screen rod 41 maintains the initial spacing of the screen rods 41 under normal screening conditions. The preload of the tension spring 74 is determined based on the minimum restoring force required for the support ring 72 to remain sleeved on the slide rod 43 under vibration. In this embodiment, the preload of the tension spring 74 is 120N.

[0049] In this embodiment, the guide rod 73 guides the movement direction of the horizontal plate 71, and each support ring 72 of the horizontal plate 71 is sleeved on the corresponding slide rod 43 when the horizontal plate 71 is in the support position, which can form a lateral limit on the free end of the screen rod 41; the tension spring 74 applies a tension force to the horizontal plate 71 toward the support position, so that the horizontal plate 71 remains in the support position during the vibration of the vibrating frame 2, reducing the possibility of the support ring 72 dislodging from the slide rod 43 due to vibration disturbance, thereby maintaining the initial screen rod spacing of the screen rod 41 under normal screening conditions.

[0050] In one embodiment, the release structure includes a push rod 53, which is fixed to the side of the moving plate 51 facing the horizontal plate 71. When the moving plate 51 moves toward the free end of the screen rod 41, the push rod 53 abuts against the horizontal plate 71 and pushes the horizontal plate 71 from the support position to the release position. When the horizontal plate 71 is in the release position, the moving plate 51 pushes the fixed column 44 into the corresponding guide groove 62.

[0051] Specifically, the end of the push rod 53 has a driving surface opposite to the horizontal plate 71, and the horizontal plate 71 has a pushing surface opposite to the driving surface. After the driving surface and the pushing surface abut against each other, the push surface has a contactable stroke along the moving direction of the moving plate 51 that covers the engagement stroke of the fixed column 44 and the guide groove 62. When the push rod 53 is driven to move by the moving plate 51, the horizontal plate 71 first moves along the guide rod 73 until each support ring 72 disengages from the corresponding slide rod 43; then, the moving plate 51 continues to move, and the cleaning block 52 pushes the fixed column 44 into the guide groove 62. This creates a defined mechanical timing between the action of the support ring 72 disengaging from the slide rod 43 and the action of the fixed column 44 entering the guide groove 62, preventing the support ring 72 from restricting the lateral displacement of the slide rod 43.

[0052] In one embodiment, the end of the push rod 53 is provided with a driving surface opposite to the horizontal plate 71, and the horizontal plate 71 is provided with a push surface opposite to the driving surface. After the driving surface and the push surface abut against each other, the moving plate 51 has a contactable stroke that covers the mating stroke of the fixed column 44 and the guide groove 62 along the moving direction. The tension spring 74 applies a tension force to the horizontal plate 71 toward the support position. When the horizontal plate 71 is in the support position, the axis of the annular hole of each support ring 72 corresponds to the axis of the corresponding slide rod 43, so that each support ring 72 is sleeved on the corresponding slide rod 43.

[0053] As the moving plate 51 returns to its initial position, the fixed column 44 gradually moves away from the guide groove 62, and the screen rods 41 restore their initial spacing under the elastic reset action. The slide rods 43 return to the position corresponding to the support rings 72. As the moving plate 51 continues to move towards its initial position, the push rod 53 no longer abuts against the horizontal plate 71, and the horizontal plate 71 returns to its support position under the tension of the tension spring 74. Each support ring 72 is then re-sleeved onto its corresponding slide rod 43. In this embodiment, the free ends of the screen rods 41 are restored to their initial arrangement before being restricted by the support rings 72, reducing the possibility of collision or misalignment between the support rings 72 and the unreset slide rods 43.

[0054] Furthermore, the drive assembly includes a lead screw 45, a motor 47, a movable seat 46, and a transmission belt. The lead screw 45 is rotatably mounted on the vibration frame 2, the movable seat 46 is threaded onto the lead screw 45, the movable plate 51 is fixedly connected to the movable seat 46, and the output shaft of the motor 47 is connected to the lead screw 45 via the transmission belt.

[0055] In this embodiment, when the motor 47 rotates forward, it drives the lead screw 45 to rotate via the transmission belt. The lead screw 45 drives the movable seat 46 and the movable plate 51 to move toward the free end of the screen rod 41. When the motor 47 rotates in reverse, the movable plate 51 returns to its initial position. The lead screw 45 has a pitch of 8mm, and the rated speed of the motor 47 is 600r / min, thereby stably driving the movable plate 51 to reciprocate along the extension direction of the screen rod 41.

[0056] Furthermore, a slide rail 54 is fixedly provided on the vibration frame 2, and the moving plate 51 slides in cooperation with the slide rail 54; two baffles 21 are also fixedly provided on the vibration frame 2, and the two baffles 21 respectively cover the lead screw 45 and the slide rail 54.

[0057] Specifically, the slide rail 54 guides the movement direction of the moving plate 51, and two baffles 21 separate the lead screw 45 and the slide rail 54 from the material drop area of ​​the sand and gravel. The openings of the baffles 21 face away from the screen rod 41 to reduce the amount of sand and gravel entering the transmission area. This embodiment reduces the impact and wear of sand and gravel on the lead screw 45 and the slide rail 54, and maintains the stability of the movement trajectory of the moving plate 51.

[0058] The above embodiment restricts the lateral elastic displacement of the free end of the screen rod 41 under normal screening conditions through the support structure, and causes different lateral elastic displacements of the free ends of the screen rods 41 under the unblocking state by releasing the structure and driving the guide structure, so that stable screening and spacing changes can be achieved under different states respectively; by utilizing the elastic reset capability of the screen rods 41 and the reset cooperation of the support structure, the screening device can restore the initial screen rod spacing and stable support state after the unblocking is completed.

[0059] Example 2: During the screening process, the vibrating frame 2 drives multiple screen rods 41 to vibrate, causing materials that meet the particle size requirements to fall through the gaps between adjacent screen rods 41, while larger particles move along the screen surface to the discharge position. When stones become wedged between adjacent screen rods 41, they can be cleaned by moving the cleaning mechanism, adjusting the relative positions of the screen rods 41, or changing the screening conditions.

[0060] In actual operation, the shape, embedding direction, surface roughness, and contact state between the stones and the screen rods 41 vary. When the cleaning mechanism passes the location of the stones, some stones may detach from the screen rods 41 under the thrust, some stones may only undergo local displacement, and others may remain in contact with and clamped to the screen rods 41 after the cleaning mechanism passes. Therefore, it is difficult to accurately reflect the actual jamming state between adjacent screen rods 41 based solely on whether the cleaning mechanism passes the location of the stones, whether the drive mechanism completes the preset stroke, or whether the drive load changes once. If a fixed stroke or a fixed number of cleaning actions are used without confirming the jamming state, insufficient cleaning stroke, continuous application of ineffective cleaning actions, or repeated application of deformation loads to the screen rods 41 may occur.

[0061] Furthermore, when the screen rod 41 undergoes relative displacement during the cleaning process, the elastic deformation of the screen rod 41 itself, the friction between transmission components, the contact between guide components, and the disturbance of residual material all affect the vibration load. Existing cleaning methods typically do not distinguish between load changes caused by the inherent structure of the device and additional load changes caused by the continuous clamping of stones, nor do they establish a correspondence between changes in the jamming state and subsequent cleaning actions, making it difficult to adapt the cleaning process for stones with different degrees of embedding to actual working conditions.

[0062] To resolve the above technical issues, please refer to [link / reference]. Figure 8 This embodiment proposes an adaptive control method for a sand and gravel waste screening decomposition card based on vibration load feedback. This embodiment uses the above-mentioned variable gap unclogging screening device for sand and gravel waste recycling as the operating object, and specifically includes the following steps: S1. Obtain the device's operation feedback signal and determine whether the device needs to be unlocked.

[0063] The operational feedback signals include the current screening runtime, screening efficiency information, and cleaning instructions issued by the operator. Screening efficiency information is obtained under normal screening conditions when the support ring 72 is fitted onto the corresponding slide bar 43, the moving plate 51 is in its initial position, and the drive component has not performed its unblocking stroke. This is to avoid interference with the screening efficiency information caused by the movement of the cleaning block 52, changes in the screen bar spacing, and the discharge of the material to be cleaned. In this embodiment, the preset cleaning interval is 60 minutes, and the preset screening efficiency operating range is 80% to 100% of the rated screening efficiency. The preset cleaning interval is set based on the actual operating patterns of the mud content in the sand and gravel waste, the material conveying volume, and the accumulated deposits on the surface of the screen bar 41; the preset screening efficiency operating range is determined by the rated processing capacity of the screening device and the allowable capacity fluctuation range. When the current screening runtime since the last cleaning reaches 60 minutes, the screening efficiency information indicates that the current screening efficiency is lower than 80% of the rated screening efficiency, or a cleaning instruction is received from the operator, it is determined that the device needs to be unblocked.

[0064] After determining that the device needs to be unblocked, the feeding of sand and gravel waste into the feed end of the vibrating frame 2 is stopped, and the vibrating frame 2 is controlled to continue vibrating to discharge the material to be cleaned. In this embodiment, the preset discharge time is 90s, which is determined based on the effective length of the screen rod 800mm, the vibration frequency 20Hz, and the conveying speed of the sand and gravel waste on the screen rod 41. This embodiment reduces the influence of residual material on the screen rod 41 before entering the unblocking stroke, and reduces the falling of material that does not conform to the screening particle size when the screen rod spacing changes.

[0065] Further, the drive guide structure includes a drive assembly, a moving plate 51, and multiple cleaning blocks 52 disposed on the moving plate 51 and slidably engaged with each screen rod 41. Each cleaning block 52 is provided with a wedge-shaped thin plate, the tip of which faces the free end of the screen rod 41. Before step S2, the drive assembly is controlled to drive the moving plate 51 to move towards the free end of the screen rod 41 along the extension direction of the screen rod 41, causing the moving plate 51 to drive each cleaning block 52 to move along the corresponding screen rod 41. The wedge-shaped thin plate cleans the deposits on the surface of the screen rod 41 and contacts the stuck stones located between adjacent screen rods 41, applying a force to the stuck stones along the extension direction of the screen rod 41. After the cleaning block 52 passes through the area where the stuck stone is located, it is not determined from the passing state of the cleaning block 52 or the single-run current change of the drive assembly that the stuck stone has been removed from the adjacent screen rod 41.

[0066] Specifically, the wedge-shaped thin plate may cause the stuck stone to move along the screen rod 41 and disengage, or it may only cause a local positional change in the stuck stone, or it may squeeze through between the stuck stone and the screen rod 41. All three scenarios can result in the cleaning block 52 passing through. Therefore, the passing state of the cleaning block 52 cannot be used as a basis for determining whether the unblocking is complete. This avoids misjudging the movement state of the cleaning block 52 as a stuck stone state, and preserves a reliable detection premise for subsequent jamming judgment based on vibration load feedback.

[0067] In one embodiment, before step S2, the operating current, duration, preset allowable overload current threshold, preset duration, and preset clearance distance of the drive component are obtained. When the operating current exceeds the preset allowable overload current threshold and the duration reaches the preset duration, the drive component is controlled to stop operating, or the drive component is controlled to drive the moving plate 51 to move a preset clearance distance in the opposite direction to its moving direction toward the free end of the screen rod 41.

[0068] In this embodiment, the preset allowable overload current threshold is 120% of the rated current of motor 47, the preset duration is 2 seconds, and the preset clearance distance is 10 mm. This current threshold is set based on the short-term overload capacity of motor 47 and the allowable load of the lead screw 45 transmission; the duration is used to filter out current fluctuations caused by the instantaneous impact of sand and gravel; the clearance distance is determined based on the minimum stroke of lead screw 45 required for the cleaning block 52 to detach from the local obstruction area. The operating current is only used to determine the overload protection action of the drive assembly and is not used as a basis for terminating the unblocking process. This embodiment protects the drive assembly when the cleaning block 52 is blocked by stuck stones, while avoiding confusion between the operating current of the drive assembly and the residual jamming response.

[0069] S2. When it is necessary to unblock, the control drive guide structure drives the free ends of each screen rod 41 to reciprocate within the unblocking stroke, so as to periodically increase the distance between adjacent screen rods 41.

[0070] Specifically, the control drive assembly drives the moving plate 51 to move, causing the push rod 53 to push the horizontal plate 71 from the support position to the release position, causing each support ring 72 to disengage from its corresponding slide rod 43. After each support ring 72 disengages from its corresponding slide rod 43, the control moving plate 51 moves, causing each fixed column 44 to enter the first diagnostic effective guide area of ​​its corresponding guide groove 62, so that the free ends of each screen rod 41 produce different lateral elastic offsets and form a first diagnostic expansion gap.

[0071] The first diagnostic expansion gap is 20% of the initial screen bar spacing of 30mm, i.e., 6mm. The first diagnostic effective guiding zone is the section of the guiding groove 62 from the entrance of each fixed column 44 to the section forming the first diagnostic expansion gap. The first diagnostic position is the position of the moving plate 51 when each fixed column 44 is at the end of the first diagnostic effective guiding zone. The first partial reset position is located on the stroke of the moving plate 51 returning from the first diagnostic position to the initial position, and the fixed column 44 remains within the guiding groove 62; at the first partial reset position, the screen bar spacing between adjacent screen bars 41 increases by 50% of the first diagnostic expansion gap, i.e., 3mm. This position is used to maintain the periodic change of the stone contact state without causing the fixed column 44 to exit the guiding groove 62.

[0072] The control drive assembly drives the moving plate 51 to reciprocate between the first diagnostic position and the first partial reset position. The frequency of the active excitation reference is determined based on the elastic response time of the screen rod 41 during a single reciprocating process, the transmission response time of the lead screw 45, and the stabilization time of the contact state of the stuck stone. In this embodiment, it is 0.5Hz, which enables the screen rod spacing to change periodically within a known stroke, and uses this known timing as the active excitation reference for subsequent vibration load feedback processing.

[0073] S3. Obtain the timing of the reciprocating motion of the free end driven by the driving guide structure, use the timing as an active excitation reference, and control the vibration frame 2 to maintain vibration.

[0074] Within the same unblocking stroke, the vibrating frame 2 maintains a vibration frequency of 20Hz and normal screening vibration intensity. 20Hz is within the commonly used vibration frequency range for sand and gravel screening devices, which can maintain material conveying conditions and allow the stuck stones to continuously withstand inertial forces during changes in screen bar spacing. The vibrating frame 2 maintains the same vibration parameters within a continuous active excitation cycle, avoiding interference from vibration parameter changes on vibration load feedback, and establishing a stable correspondence between the active excitation reference and the load feedback of the vibrating frame 2.

[0075] S4. Obtain the load feedback of the vibration frame 2 in each phase interval corresponding to the active excitation reference, and determine the actual synchronous vibration load response.

[0076] In this embodiment, the active excitation reference includes a recurring gap-expansion phase and a partial reset phase. Taking an active excitation cycle of 2 seconds as an example, the 1-second interval from the moving plate 51 moving from the first partial reset position to the first diagnostic position is the gap-expansion phase, and the 1-second interval from the moving plate 51 returning from the first diagnostic position to the first partial reset position is the partial reset phase. The load feedback of the vibration frame 2 is segmented according to the gap-expansion phase and the partial reset phase, and the load feedback in each phase interval is obtained. Based on the difference between the load feedback in the gap-expansion phase and the partial reset phase, the actual synchronous vibration load response is determined.

[0077] In this embodiment, the load feedback of the vibration frame 2 is the load rate output by the drive source driving the vibration frame 2. The drive source provides the load rate to the control unit via a communication interface at a refresh rate of 100Hz. The control unit uses the average load rate within each phase interval as the phase load value. The 100Hz refresh rate is higher than the 20Hz vibration frequency and can provide multiple load samples within a 1s phase interval. This value is determined based on the need for phase segmentation comparison of vibration load changes. In this embodiment, the actual synchronous vibration load response synchronized with the active excitation reference is obtained from the load changes of the vibration frame 2 in two phase intervals.

[0078] In other embodiments, the load feedback of the vibration frame 2 can also be the motor current, torque estimate, active power, or other operating information with mechanical load correspondence output by the drive source driving the vibration frame 2. The control unit determines the actual synchronous vibration load response based on the type of operating information that the existing drive source can provide, using the average value of the phase interval, the difference between adjacent phase intervals, synchronous correlation characteristics, or envelope change, without requiring the vibration load feedback to exhibit a specific frequency sideband, a specific frequency, or a specific waveform as a necessary condition for determining the residual jamming response.

[0079] S5. Obtain the structural response benchmark corresponding to the active excitation reference under the unobstructed state, and determine the residual obstruction response based on the actual synchronous vibration load response and the structural response benchmark.

[0080] Once it is confirmed that there are no stones stuck between adjacent screen rods 41, the drive guide structure is controlled to operate with the same vibration parameters, the same movement trajectory of the moving plate 51, and the same unblocking stroke to obtain the load feedback corresponding to the vibrating frame 2. The load feedback in the unblocked state includes the elastic deformation of the screen rod 41, the movement of the slide bar 43 in the slot 42, the cooperation between the fixed column 44 and the guide groove 62, and the inherent response generated by the transmission friction of the drive assembly.

[0081] The no-jamming state can be established during the equipment commissioning phase after the operator confirms that there are no stuck stones between adjacent screen bars 41, or it can be established after the cleaning is completed and the residual jamming response is confirmed to be within the preset unjamming completion range during the verification phase. If a structural response benchmark corresponding to the current vibration parameters, the movement trajectory of the moving plate 51, and the unjamming stroke is not established, the control unit does not determine the residual jamming response based on the absolute value of the load feedback from the vibration frame 2.

[0082] In this embodiment, three consecutive active excitation cycles without jamming are executed during the equipment commissioning phase. The corresponding actual synchronous vibration load response is calculated for each cycle, and the average value of the three actual synchronous vibration load responses is taken as the structural response benchmark. Three active excitation cycles are used to eliminate random deviations caused by residual material disturbance within a single cycle without prolonging the equipment commissioning time. The actual synchronous vibration load response is compared with the structural response benchmark, and the difference between the two is determined as the residual jamming response. The synchronous load influence generated by the device's own structural movement in the unjammed state is subtracted, so that the residual jamming response corresponds to the continuous contact, clamping, and friction state between the jamming stone and the screen rod 41.

[0083] S6. Obtain the changes in the residual jamming response within multiple consecutive active excitation cycles, and control the drive guide structure to maintain the current unblocking stroke, enter the next unblocking stroke, or terminate the unblocking process based on the changes in the residual jamming response.

[0084] Specifically, the preset unblocking completion range, preset number of consecutive cycles, and preset verification duration are obtained. In this embodiment, the preset unblocking completion range is that the residual jamming response does not exceed 5% of the structural response benchmark, the preset number of consecutive cycles is 3 active excitation cycles, and the preset verification duration is 6 seconds. The 5% range is set based on the load fluctuation range of repeatedly obtaining the structural response benchmark under the unblocked state; the 3 active excitation cycles are used to avoid misjudgment caused by a single load disturbance; 6 seconds corresponds to 3 active excitation cycles, used to verify whether the jamming stone has reformed its clamping position in the partially reset position.

[0085] When the residual jamming response is within the preset unblocking completion range for three consecutive active excitation cycles, the drive guide structure is controlled to keep the moving plate 51 in the first partial reset position, and the vibrating frame 2 is controlled to continue vibrating. The load feedback of the vibrating frame 2 within 6 seconds is acquired, and the actual synchronous vibration load response of the verification stage is determined based on the load feedback. The residual jamming response is then re-determined based on the structural response benchmark. When the re-determined residual jamming response is within the preset unblocking completion range, the drive guide structure is controlled to terminate the unblocking process. When the re-determined residual jamming response is outside the preset unblocking completion range, the drive guide structure is controlled to maintain the current unblocking stroke and continue to drive the free ends of each screen rod 41 to reciprocate, thereby distinguishing between the case where the stuck stone has been removed from the screen rod 41 and the case where the stuck stone is only temporarily loosened in the gap-expanding state.

[0086] Furthermore, the unblocking stroke includes multiple graded unblocking strokes. The preset maximum number of pulses and the preset maximum graded unblocking stroke corresponding to each graded unblocking stroke are obtained. In this embodiment, the first graded unblocking stroke corresponds to a first diagnostic gap increase of 6mm, the second graded unblocking stroke corresponds to a screen bar spacing increase of 12mm, and the third graded unblocking stroke corresponds to a screen bar spacing increase of 18mm. The third graded unblocking stroke is the preset maximum graded unblocking stroke. Each graded stroke is determined based on the maximum lateral offset of the screen bar (18mm) and the requirement to maintain recoverable elastic deformation. The preset maximum number of pulses corresponding to each graded unblocking stroke is 10 times, which is determined based on the balance between the fatigue life of the screen bar 41 under repeated bending and the unblocking efficiency.

[0087] When the current graded unblocking stroke is not the preset maximum graded unblocking stroke, and the residual jamming response is still outside the preset unblocking completion range after reaching the preset maximum number of pulses corresponding to the current graded unblocking stroke, the control drive guide structure drives the free ends of each screen rod 41 into the next graded unblocking stroke, and obtains or calls the structural response benchmark corresponding to the next graded unblocking stroke. When the current graded unblocking stroke is the preset maximum graded unblocking stroke, and the residual jamming response is still outside the preset unblocking completion range after reaching the preset maximum number of pulses, the control drive guide structure ends the gap widening action, records the residual jamming response and the current graded unblocking stroke of this cleaning cycle, and outputs a maintenance prompt. The control drive guide structure moves the moving plate 51 to the initial position, causes the fixed column 44 to exit the effective guide area of ​​the guide groove 62, and causes the screen rod 41 to return to the initial arrangement position under the elastic action; then the control vibrating frame 2 pauses vibration or adjusts to the preset reset vibration state, causes the push rod 53 to leave the horizontal plate 71, the tension spring 74 drives the horizontal plate 71 back to the support position, and each support ring 72 is re-fitted onto the corresponding slide rod 43. After resetting, the feeding remains stopped until the operator completes maintenance and issues a new screening command. This method adapts the screen bar spacing to changes in stroke based on the residual jamming response, and avoids continuously increasing the lateral offset of the screen bars when the unblocking condition cannot be met.

[0088] The movement trajectory of the moving plate 51, the position of the fixed column 44 in the guide groove 62, and the lateral elastic offset of the free end of the screen rod 41 are different for different graded unblocking strokes, resulting in different actual synchronous vibration load responses in the unblocked state. Therefore, after entering the next graded unblocking stroke, the control unit re-acquires the load feedback of the vibration frame 2 in the unblocked state under the same vibration parameters, the same movement trajectory of the moving plate 51, and the same graded unblocking stroke, or calls the pre-established corresponding structural response benchmark to avoid using the structural response benchmark of the previous graded unblocking stroke for the next graded unblocking stroke.

[0089] In one embodiment, the control unit selects a first operating mode, a second operating mode, a third operating mode, or a maintenance holding mode based on the operating feedback signal. The first operating mode only controls the moving plate 51 to move the cleaning block 52 along the screen rod 41; the second operating mode performs a first diagnostic gap widening after the first operating mode; the third operating mode performs a graded gap widening stroke if the gap widening condition is not met in the second operating mode; the maintenance holding mode stops widening the screen rod spacing and outputs a maintenance prompt if the preset maximum graded gap widening stroke does not meet the gap widening condition. By selecting the corresponding cleaning action among the first operating mode, second operating mode, third operating mode and maintenance mode based on the operation feedback signal, the cleaning block 52 is moved first when there are only attachments on the surface of the screen rod 41. When there is residual jamming, the first diagnostic gap widening and graded unblocking strokes are executed in sequence. This avoids directly driving the screen rod 41 into a large unblocking stroke when the degree of jamming is low. When the preset maximum graded unblocking stroke still does not reach the unblocking completion condition, the expansion of the screen rod spacing is stopped and a maintenance prompt is output. This keeps the lateral elastic offset of the screen rod within the allowable range corresponding to the preset maximum graded unblocking stroke, thereby reducing the possibility of repeated bending of the screen rod 41, overload of transmission components and abnormal operation of the device caused by continuous unblocking action.

[0090] After the card is terminated in step S6, the preset reset vibration state is obtained.

[0091] In this embodiment, the preset reset vibration state includes a paused vibration state or a low vibration state with a vibration frequency of 5Hz and a vibration intensity of 30% of the normal screening vibration intensity. This state is determined based on the requirement to reduce the relative vibration amplitude when the support ring 72 and slide rod 43 are re-fitted. The control drive assembly drives the moving plate 51 to move to the initial position, causing each fixed column 44 to exit the effective guide area of ​​the corresponding guide groove 62, so that each screen rod 41 returns to its initial arrangement position under elastic action.

[0092] After each screen rod 41 returns to its initial arrangement position, the vibrating frame 2 is controlled to pause vibration or adjust to a preset reset vibration state. The moving plate 51 is controlled to continue moving to its initial position, causing the push rod 53 to release its push on the horizontal plate 71, and the tension spring 74 to drive the horizontal plate 71 back to its support position, so that each support ring 72 is re-fitted onto its corresponding slide rod 43. After each support ring 72 is re-fitted onto its corresponding slide rod 43, the vibrating frame 2 is controlled to restore the normal screening vibration parameters of 20Hz, and the feeding of sand and gravel waste into the feed end of the vibrating frame 2 is resumed. The support rings 72 are fitted onto the slide rods 43 only after the screen rods 41 have returned to their initial arrangement position, reducing the possibility of collision or misalignment between the support rings 72 and slide rods 43 during the reset process.

[0093] The technical effect of the above embodiment is that by making the free end of the screen rod 41 reciprocate within the known unblocking stroke and using the motion sequence as an active excitation reference, the load feedback of the corresponding phase interval is obtained when the vibrating frame 2 maintains vibration. Then, the residual jamming response is determined by using the structural response benchmark under the unblocking state. This enables subsequent unblocking actions to be maintained, upgraded, or terminated according to the actual jamming state. The cleaning mechanism no longer uses the area where the jammed stone is located as the basis for determining the removal of the jammed stone, thereby reducing the invalid actions and repeated deformation of the screen rod 41 caused by fixed cleaning times.

[0094] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. An adaptive control method for a sand and gravel waste screening and decomposition card based on vibration load feedback, applied to a variable gap unclogging screening device for sand and gravel waste recycling, the device comprising a vibrating frame, multiple screen rods, and a drive guide structure, wherein each screen rod comprises a free end and a fixed end, characterized in that... Includes the following steps: S1. Obtain the operation feedback signal of the device and determine whether the device needs to be unlocked; S2. When it is necessary to unblock, the drive guide structure is controlled to drive the free ends of each screen rod to reciprocate within the unblocking stroke, so as to periodically increase the distance between adjacent screen rods. S3. Obtain the timing sequence of the drive guide structure driving the reciprocating motion of the free end, use the timing sequence as an active excitation reference, and control the vibration frame to maintain vibration; S4. Obtain the load feedback of the drive source of the vibration frame in each phase interval corresponding to the active excitation reference, and determine the actual synchronous vibration load response. S5. Obtain the structural response benchmark corresponding to the active excitation reference under the unobstructed state, and determine the residual obstruction response based on the actual synchronous vibration load response and the structural response benchmark. S6. Obtain the changes in the residual jamming response within multiple consecutive active excitation cycles, and control the drive guide structure to maintain the current unblocking stroke, enter the next unblocking stroke, or terminate the unblocking process based on the changes in the residual jamming response.

2. The adaptive control method according to claim 1, characterized in that, The drive guide structure includes a drive assembly, a movable plate, and multiple cleaning blocks disposed on the movable plate and slidably engaged with each of the screen rods. Each cleaning block is provided with a wedge-shaped thin plate, the tip of which faces the free end of the screen rod. Before step S2, the following steps are also included: The drive assembly is controlled to drive the moving plate toward the free end of the screen rod along the extension direction of the screen rod, so that the moving plate drives each of the cleaning blocks to move along the corresponding screen rod; The wedge-shaped thin plates are used to clean the adhering substances on the surface of the corresponding screen rods, and each wedge-shaped thin plate is brought into contact with the stuck stone located between adjacent screen rods to apply a force to the stuck stone along the extension direction of the screen rod; After the cleaning block passes through the area where the stuck stone is located, it is not determined from the passing state of the cleaning block or the change in the single operation current of the drive component that the stuck stone has been removed from the adjacent screen bar.

3. The adaptive control method according to claim 2, characterized in that, The following steps are included before step S2: The operating current, duration, preset allowable overload current threshold, preset duration, and preset backoff distance of the drive component are obtained. When the operating current exceeds the preset allowable overload current threshold and the duration reaches the preset duration, the drive component is controlled to stop operating, or the drive component is controlled to drive the moving plate to move the preset clearance distance in a direction opposite to the extension direction of the screen rod. The operating current is used only to determine the overload protection action of the drive component.

4. The adaptive control method according to claim 2, characterized in that, The device further includes a support structure, a release structure, a horizontal plate, multiple support rings, a push rod, a tension spring, a guide plate, a slide rod, and a fixed column. Each screen rod has a slot at its free end, and the slide rod is slidably disposed within the slot. The fixed column is disposed at the extended end of the slide rod. The support rings are respectively sleeved on each slide rod. The push rod is disposed on the moving plate. The tension spring connects the horizontal plate and the vibrating frame. The guide plate has guide grooves corresponding to each fixed column, and the guide grooves include a first diagnostic effective guide area. Step S2 specifically includes the following steps: The drive assembly is controlled to move the movable plate, causing the push rod to push the horizontal plate from the support position to the release position, so that each support ring disengages from the corresponding slide rod. After each of the support rings disengages from the corresponding slide bar, the moving plate is controlled to move, so that each of the fixed columns enters the first diagnostic effective guide area of ​​the corresponding guide groove, so that the free ends of each of the screen rods produce different lateral elastic offsets and form a first diagnostic expansion gap; The position of the movable plate when each of the fixed columns is located in the corresponding first diagnostic effective guide area is determined as the first diagnostic position; The drive assembly is controlled to drive the moving plate to reciprocate between the first diagnostic position and the first partial reset position. The first partial reset position is located on the travel distance of the moving plate from the first diagnostic position back to the initial position, and each of the fixed posts remains in the corresponding guide groove.

5. The adaptive control method according to claim 4, characterized in that, The timing sequence in step S3 includes the recurring gap widening phase and the partial reset phase; step S4 specifically includes the following steps: The load feedback of the drive source is segmented according to the widening phase and the partial reset phase; Obtain the load feedback of the drive source within each expansion phase and each partial reset phase; The actual synchronous vibration load response is determined based on the differences between the load feedback in each expansion phase and each partial reset phase.

6. The adaptive control method according to claim 5, characterized in that, The specific steps in step S5 of obtaining the structural response benchmark include: The load feedback of the drive source is obtained under the unobstructed state where there are no stones stuck between adjacent screen bars, with the same vibration parameters, the same moving plate trajectory, and the same unblocking stroke as the active excitation reference. The structural response benchmark is determined based on the load feedback under the unobstructed state; wherein, the load feedback under the unobstructed state is obtained during the equipment debugging phase, during the cleaning cycle confirming that there are no stuck stones between adjacent screen bars, or in a stable state after one unblocking. The residual jamming response is determined based on the difference between the actual synchronous vibration load response and the structural response benchmark.

7. The adaptive control method according to claim 6, characterized in that, Step S6 specifically includes the following steps: Get the preset card unlocking completion range, preset number of consecutive cycles, and preset verification duration; When the residual jamming response is within the preset unblocking completion range within the preset number of consecutive active excitation cycles, the drive guide structure is controlled to keep the moving plate in the first partial reset position, and the vibration frame is controlled to maintain vibration. Obtain the load feedback of the drive source within the preset verification time, determine the actual synchronous vibration load response of the verification stage based on the load feedback, and re-determine the residual jamming response based on the actual synchronous vibration load response of the verification stage and the structural response benchmark. When the redefined residual jamming response is within the preset unblocking completion range, the drive guide structure is controlled to terminate the unblocking process; When the redefined residual jamming response is outside the preset unblocking completion range, the drive guide structure is controlled to maintain the current unblocking stroke and continue to drive the free ends of each screen rod to reciprocate.

8. The adaptive control method according to claim 7, characterized in that, The card unlocking process includes multiple tiered card unlocking processes and also includes the following steps: Obtain the preset maximum number of pulses and the preset maximum level of card unlocking stroke corresponding to each of the aforementioned graded card unlocking strokes; When the current graded unblocking stroke is not the preset maximum graded unblocking stroke, and the residual jamming response is still outside the preset unblocking completion range after reaching the preset maximum number of pulses corresponding to the current graded unblocking stroke, the drive guide structure is controlled to drive the free ends of each screen rod into the next graded unblocking stroke, and the structural response benchmark corresponding to the next graded unblocking stroke is obtained or called. When the current graded card unblocking stroke is the preset maximum graded card unblocking stroke, and the residual card resistance response is still outside the preset card unblocking completion range after reaching the preset maximum number of pulses corresponding to the current graded card unblocking stroke, the drive guide structure is controlled to end the gap widening action, the residual card resistance response and the current graded card unblocking stroke of this cleaning cycle are recorded, and a maintenance prompt is output.

9. The adaptive control method according to claim 8, characterized in that, After step S6 terminates the card unlocking process, the following steps are also included: Obtain the preset reset vibration state; The drive assembly is controlled to drive the moving plate to the initial position, so that each of the fixed columns exits the effective guide area of ​​the corresponding guide groove, and so that each of the screen rods returns to the initial arrangement position under the elastic action; After each of the screen rods returns to its initial arrangement position, the vibrating frame is controlled to pause vibration or adjust to the preset reset vibration state; The movable plate is controlled to continue moving to the initial position, so that the push rod releases the push on the horizontal plate and the tension spring drives the horizontal plate back to the support position, so that each support ring is re-sleeved onto the corresponding slide rod; After each of the support rings is re-sleeved onto the corresponding slide bar, the vibrating frame is controlled to restore normal screening vibration parameters.

10. The adaptive control method according to claim 1, characterized in that, Step S1 specifically includes the following steps: Get the preset cleaning interval, preset screening efficiency operating range, and preset discharge time; Obtain the current screening runtime, screening efficiency information, and cleaning instructions issued by the operator since the last cleaning was completed; When the current screening runtime reaches the preset cleaning interval, the screening efficiency information indicates that the current screening efficiency is outside the preset screening efficiency operating range, or the cleaning command is obtained, it is determined that the device needs to be unlocked. After determining that the device needs to be unblocked, stop feeding sand and gravel waste into the feed end of the vibrating frame, and control the vibrating frame to maintain vibration until the preset discharge time is reached, so as to discharge the material to be cleaned.

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