A coal gangue double belt combined dry separation system and screening method

Abstract

The present invention belongs to the technical field of intelligent coal preparation, and in particular relates to a gangue double-belt combined dry selection system and a screening method. It includes a dynamic screening machine, a gantry manipulator, a manipulator belt, an air-spraying sorting mechanism, an air-spraying belt and a coal gangue arranging device. The dynamic screening machine is provided with an upper discharge port for allowing materials with a particle size ≥150mm to pass through, a middle discharge port for allowing materials with a particle size between 50mm and 150mm to pass through, and a lower discharge port for allowing materials with a particle size <50mm to pass through; the upper discharge port is connected to the manipulator belt, the middle discharge port is connected to the air-spraying belt, a first coal gangue identification device and a gantry manipulator are arranged above the manipulator belt, the first coal gangue identification device identifies and distinguishes coal and gangue in the material, and the gantry manipulator picks the coal and gangue into the coal bin or gangue bin according to the identification result of the first coal gangue identification device; a coal gangue arranging device is arranged in front of the air-spraying belt, a second coal gangue identification device is arranged above the middle of the air-spraying belt, and the second coal gangue identification device identifies and distinguishes coal and gangue in the material.

Description

Technical Field

[0001] The present invention belongs to the technical field of intelligent coal preparation, and in particular relates to a gangue double-belt combined dry separation system and a screening method. Background Art

[0002] Raw coal mined underground is always mixed with varying amounts of gangue, making coal preparation a critical step in improving coal quality. Coal preparation is generally divided into wet and dry separation. Particles or powdered coal with a particle size of ≤50mm enter the coal washing line, while lumps with a particle size greater than 50mm undergo dry separation.

[0003] In recent years, intelligent dry sorting equipment has developed rapidly. Recognition technologies primarily fall into two categories: radiographic and image-based. Sorting methods primarily rely on air jets, robotic grippers, and mechanical pushers. Air jet sorting is unsuitable for large-particle materials and requires pre-alignment of the material. Existing alignment devices employ transverse guide plates installed on the belt to divert material already on the belt. This diversion process can cause material jamming, and the continuous sliding of material on the belt causes significant wear. When worn areas of the belt are contaminated with coal dust, they often resemble coal in the image, leading to misidentification of "coal" and compromising image detection accuracy. Robotic grippers and mechanical pushers are used to sort large pieces of material without pre-alignment. However, due to speed limitations of these grippers and mechanical pushers, sorting efficiency is relatively low. Mechanical pushers operate by "pushing" waste rock into the waste rock channel. This sliding of the waste rock on the belt also causes significant wear. Furthermore, if coal is present around the waste rock, the mechanical pusher will push the coal into the waste rock bin. Summary of the Invention

[0004] In order to expand the overall sortable particle size range of the system, improve the sorting efficiency, and reduce the wear of the material on the belt, the present invention provides a coal gangue double-belt combined dry sorting system and screening method.

[0005] The present invention adopts the following technical scheme: a coal gangue double belt combined dry sorting system, including a dynamic screen, a controller, a gantry manipulator, a manipulator belt, an air-spray sorting mechanism, an air-spray belt and a coal gangue arranging device, the dynamic screen is provided with an upper discharge port for allowing materials with a particle size of ≥150mm to pass through, a middle discharge port for allowing materials with a particle size of 50mm~150mm to pass through, and a lower discharge port for allowing materials with a particle size of <50mm to pass through; the upper discharge port is connected to the manipulator belt, the middle discharge port is connected to the air-spray belt, a first coal gangue identification device and a gantry manipulator are provided above the manipulator belt, the first coal gangue identification device identifies and distinguishes coal and gangue in the material, and the gantry manipulator sorts the coal and gangue according to the first coal gangue identification device. The gangue identification device picks the coal and gangue into the coal bin or gangue bin according to the results of the identification; a gangue straightening device is set at the front of the air-spraying belt, and a second gangue identification device is set above the middle of the air-spraying belt. The second gangue identification device identifies and distinguishes the coal and gangue in the material. The air-spraying belt is divided into multiple channels according to the material channel of the straightening mechanism, and each channel is further subdivided into multiple virtual sub-channels. Multiple air-spray sorting mechanisms are set at the exits of the multiple rows of material channels at the tail of the air-spraying belt. Each air-spray sorting mechanism corresponds to a virtual sub-channel of the air-spraying belt. The air-spray sorting mechanism picks the coal and gangue into the coal bin or gangue bin according to the identification results of the second gangue identification device; the first gangue identification device and the second gangue identification device are connected to the controller.

[0006] Furthermore, the gantry manipulator includes a gripper fixing frame, a gripper screw, a gripper guide rail, a screw slider, a guide rail base, a gripper motor, a mobile gripper, a guide rail slider and a fixed gripper. The gripper screw and the gripper guide rail are installed on the gripper fixing frame through the guide rail base. The gripper screw is driven by the gripper motor. The gripper guide rails are symmetrically arranged on both sides of the gripper screw. A screw slider is provided on the gripper screw, and a guide rail slider is provided on the gripper guide rail. The screw slider and the guide rail slider are equipped with the same movable jaw. The movable claw is also equipped with a fixed claw at the bottom of the claw fixing frame. The movable claw and the fixed claw are symmetrically arranged. The gantry manipulator is provided with two groups of grippers consisting of movable claws and fixed claws, namely 1# claw and 2# claw. The claw screw stroke of 1# claw is 50mm~250mm, which is used to grab gangue with a particle size of ≤250mm. The screw stroke of 2# claw is 50mm~400mm, which is used to grab gangue with a particle size of 250mm~400mm.

[0007] The air-spray sorting mechanism includes an air nozzle controlled by a high-pressure air valve. The air nozzle of each air-spray sorting mechanism is coded according to the coding rule ab, where a is the channel number and b is the virtual sub-channel number. A coal bin is set at the end of the air-spray belt near the belt, and a gangue bin is set away from the belt. If the material is coal, it will fall directly into the coal bin. If the material is gangue, it will be blown into the gangue bin by the high-pressure gas blown out by the air nozzle during the falling process.

[0008] The entire array device includes vertical guide plates, guide plate fixings, guide plate connecting rods, fixing clips and the entire array device fixing frame. Multiple groups of vertical guide plates are arranged side by side, and funnel-shaped channels are formed from top to bottom between adjacent vertical guide plates. Guide plate connecting rods are passed through the vertical guide plates. The guide plate connecting rods are fixed to the guide plates through the guide plate fixings, and the two ends of the guide plate connecting rods are fixed to the entire array device fixing frame through fixing clips.

[0009] The deflector fixing part includes an elastic fixing ring, a hexagonal bolt and a hexagonal nut. The elastic fixing ring is a semicircular arc structure. Extension parts are provided at both ends of the semicircular arc structure. The extension parts are provided with through holes. Hexagonal bolts are provided in the through holes. The ends of the hexagonal bolts are fastened by hexagonal nuts.

[0010] The middle-level discharge port of the dynamic screen is located just above the blanking area of ​​the entire array device. After the material falls, it is guided by the vertical guide plates under its own gravity and randomly falls into a channel composed of vertical guide plates, realizing channel blanking. When passing through the guide plate connecting rod, due to the limitation of the installation height of the guide plate connecting rod, the stacked materials are flattened on the belt to complete the channel arrangement.

[0011] A screening method for a gangue double-belt combined dry separation system comprises the following steps:

[0012] S100: The gangue material is fed into the dynamic screen. After screening by the dynamic screen, the material with a particle size of ≥150mm enters the manipulator belt through the upper discharge port, the material with a particle size of 50mm~150mm enters the air injection belt through the middle discharge port, and the material with a particle size of <50mm enters the coal preparation plant through the lower discharge port.

[0013] S200: Coal and gangue with a particle size of ≥150mm enter the manipulator belt. The speed range of the manipulator belt is 0.5m / s-1m / s. The first coal gangue identification device detects the material and obtains the positioning coordinates of the material on the belt. x br1 , y br1 ),( x br2 , y br2 ), ( x br0 , y br0 )] and category recognition results. When the target recognition result is coal, no further information processing is performed; when the target recognition result is gangue, x br2 - x br1 The value of replaces the particle size of the material along the width direction. If the value is ≤250mm, an action command is issued to the 1# gripper, otherwise an action command is issued to the 2# gripper.

[0014] S300: Coal and gangue with a particle size of 50mm~150mm fall into the air-jet belt through the middle-level discharge port of the dynamic screen machine, and the air-jet belt speed is ≥1m / s; the middle-level discharge port of the dynamic screen machine is located directly above the drop zone of the entire array device. After falling, the material passes through the vertical guide plate under its own gravity and falls randomly into a channel to complete the channel arrangement.

[0015] S400: The material passes through the second gangue identification device and obtains the positioning coordinates of the material on the belt [( x ba1 , y ba1 ),( x ba2 , y ba2 ), ( x ba0 , y ba0 )] and category identification results. If the material is coal, it will fall directly into the coal bin; if the identification result is gangue, it will be blown into the gangue bin by the high-pressure gas blown out by the air-spray sorting mechanism during the falling process.

[0016] In step S200, according to the center point of the material y Coordinate value y br0 , determine the grabbing position and action time of 1# or 2# claw, grab the gangue and put it into the gangue bin, and the coal falls into the coal bin along the belt movement; under the manipulator belt coordinate system, the manipulator grabs y The position of the direction is fixed and can be moved along x Direction and z Direction movement; when the gangue moves along the belt to the robot y Grab position of direction y r At the same time, the manipulator grabs the gangue and puts it into the gangue bin, and the coal moves along the belt and falls into the coal bin; according to the center point of the material y Axis coordinates y br0 and formula Calculate the robot action delay, t mr is the manipulator action delay, t' is the time it takes for the manipulator to reach the grasping point from the initial position, The time for the host computer to calculate the detection target and send the detection results is v r .

[0017] In step S400, the air nozzle for performing the jetting action is determined according to the gangue positioning coordinates: according to the upper left corner and the lower right corner of the gangue x coordinate[ xba1 , x ba2 ] Determine the channel number and sub-channel interval where the gangue is located. If x ba1 and x ba2 are all located in the same sub-channel interval, the air nozzle corresponding to the channel performs the jet action; if x ba1 and x ba2 Located in different sub-channel intervals, the air nozzles corresponding to the two sub-channels and all the sub-channels between the two sub-channels all perform the jet action; according to the center point y coordinate y ba0 and formula Determine the air jet waiting time of the air jet sorting mechanism. The position coordinates of the air nozzle in the belt running direction are: y a , installed under the belt h a At, the air spray belt speed is v a .

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1) The present invention combines the advantages of robot sorting and air-spray sorting: the air-spray mechanism has a fast sorting speed and can match a faster material transportation speed, but it is difficult to blow out materials with a particle size greater than 150mm, and they need to rely on the robot to grab them. Since the robot takes a long time to perform an action, the running speed of the belt is limited. A coal gangue double-belt combined dry sorting system is equipped with a double-belt sorting system with multiple actuators. A grading screen is set at the front end of the belt to divert the material to the robot belt and the air-spray belt according to the particle size. Different belt speeds are set according to the type of sorting mechanism, so that the system can simultaneously sort coal and gangue with a particle size of 50mm-400mm, and can ensure the maximum speed at which the robot belt and the air-spray belt can effectively complete the sorting, thereby maximizing the coal gangue sorting efficiency.

[0020] 2) The novel alignment device designed in the present invention arranges the materials according to channels during their falling process, thus avoiding wear on the belt during sliding drainage on the belt, which is beneficial to extending the belt life and reducing costs. At the same time, it avoids the problem of decreased image recognition accuracy caused by changes in the belt surface state.

[0021] 3) The air jet mechanism control system of the present invention can control the corresponding position and number of air nozzles to perform air jet action according to the detected gangue size and position, ensuring that gangue of all particle sizes can be successfully blown out. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of a coal gangue double belt combined dry separation system;

[0023] Figure 2 This is the positive triaxial drawing of the dynamic screen machine;

[0024] Figure 3 This is the coordinate transformation principle diagram;

[0025] Figure 4 This is the three-axis projection of the gantry manipulator's gripper;

[0026] Figure 5 This is the three-axis projection of the mobile claw of the gantry manipulator;

[0027] Figure 6 This is the three-axis projection of the fixed claw of the gantry manipulator;

[0028] Figure 7 It is the positive triaxial projection of the entire array;

[0029] Figure 8 This is the front view of the deflector link (left half shaft only);

[0030] Figure 9 It is the positive triaxial projection of the fixed bayonet;

[0031] Figure 10 This is a front view of the schematic diagram of the guide plate connecting rod fixing;

[0032] Figure 11 It is the left side view of the schematic diagram of the guide plate connecting rod fixing;

[0033] Figure 12 It is the left side view of the deflector fixing part;

[0034] Figure 13 It is a front view of the schematic diagram of the guide plate fixing;

[0035] Figure 14 This is a schematic diagram of the flow diversion of the entire array of devices;

[0036] Figure 15 This is an example of robot belt image detection;

[0037] Figure 16 This is an example of air-jet belt image detection;

[0038] In the figure: 1-coal, 2-gangue, 3-moving screen, 4-gangue identification device, 5-controller, 6-gantry manipulator, 7-manipulator belt, 8-air spray sorting mechanism, 9-air spray belt, 10-gangue arranging device, 3.1-moving screen inlet, 3.2-upper screening round rod, 3.3-upper screening rib, 3.4-middle screening plate, 3.5-upper discharge port, 3.6-middle discharge port, 3.7-spring base, 3.8-lower discharge port, 3.9-moving screen motor, 3.10-vibrator, 6.1-hand claw fixing frame, 6 .2-hand claw screw, 6.3-hand claw guide rail, 6.4-screw slider, 6.5-guide rail base, 6.6-hand claw motor, 6.7-moving claw, 6.8-guide rail slider, 6.9-fixed claw, 6.7.1 moving claw fixing frame, 6.7.2 moving claw single claw, 10.1-vertical guide plate, 10.2-guide plate fixing, 10.3-guide plate connecting rod, 10.4-fixing buckle, 10.5-entire device fixing frame, 10.2.1-elastic fixing ring, 10.2.2-hexagonal bolt, 10.2.3-hexagonal nut. DETAILED DESCRIPTION

[0039] like Figure 1 As shown, a coal gangue double-belt combined dry sorting system includes a dynamic screen 3, a controller 5, a gantry manipulator 6, a manipulator belt 7, an air-spray sorting mechanism 8, an air-spray belt 9 and a coal gangue arranging device 10. The dynamic screen 3 is provided with an upper discharge port 3.5 for allowing materials with a particle size of ≥150 mm to pass through, a middle discharge port 3.6 for allowing materials with a particle size between 50 mm and 150 mm to pass through, and a lower discharge port 3.8 for allowing materials with a particle size of <50 mm to pass through; the upper discharge port 3.5 is connected to the manipulator belt 7, and the middle discharge port 3.6 is connected to the air-spray belt 9. A first coal gangue identification device and a gantry manipulator 6 are provided above the manipulator belt 7. The first coal gangue identification device identifies and distinguishes coal and gangue in the material, and the gantry manipulator 6 According to the results of identification by the first gangue identification device, the coal and gangue are respectively picked into the coal bin or gangue bin; a gangue arranging device 10 is arranged at the front of the air-spraying belt 9, and a second gangue identification device is arranged above the middle of the air-spraying belt 9. The second gangue identification device identifies and distinguishes the coal and gangue in the material. The air-spraying belt 9 is divided into multiple channels according to the material channel of the arranging mechanism, and each channel is further subdivided into multiple virtual sub-channels. Multiple air-spraying sorting mechanisms 8 are arranged at the outlets of the multiple rows of material channels at the tail of the air-spraying belt 9. Each air-spraying sorting mechanism 8 corresponds to a virtual sub-channel of the air-spraying belt. The air-spraying sorting mechanism picks the coal and gangue into the coal bin or gangue bin according to the identification results of the second gangue identification device; the first gangue identification device and the second gangue identification device are connected to the controller 5.

[0040] The air-spray sorting mechanism 8 includes an air nozzle controlled by a high-pressure air valve. Each air nozzle of the air-spray sorting mechanism 8 is coded, and the coding rule is ab, where a is the channel number and b is the virtual sub-channel number. A coal bin is set near the end of the air-spray belt, and a gangue bin is set away from the belt. If the material is coal, it will fall directly into the coal bin. If the material is gangue, it will be blown into the gangue bin by the high-pressure gas blown out by the air nozzle during the falling process.

[0041] like Figure 2 As shown, the dynamic screen machine 3 includes a dynamic screen machine feed port 3.1, an upper screening rod 3.2, an upper screening rib 3.3, a middle screening plate 3.4, an upper discharge port 3.5, a middle discharge port 3.6, a spring base 3.7, a lower discharge port 3.8, a vibrating screen motor 3.9, and an exciter 3.10. The dynamic screen machine housing is fixed to the spring base via high-strength bolts. The vibrating screen motor drives the exciter eccentric block to rotate at high speed, stimulating the vibrating screen housing to produce a circular motion of a certain amplitude. The material on the inclined screening plate then produces a continuous throwing motion, and material smaller than the sieve hole will fall into the next layer of screening plate. The upper screening device is composed of an upper screening rod and upper screening ribs. The upper screening rod is connected to the vibrating screen housing via high-strength bolts, and the upper screening ribs are connected to the upper screening rod by welding. The middle screening plate is welded into a mesh plate by ribs of the same width and is fixed to the vibrating screen box by bolts.

[0042] The upper screening device is welded together by upper screening rods 3.2 and upper screening ribs 3.3. After screening on the upper layer, materials with a particle size of 150 mm or larger pass through upper discharge port 3.5 onto the manipulator belt 7. Materials with a particle size of less than 150 mm fall onto the middle screening plate 3.4. The middle screening plate 3.4 is composed of rigidly connected steel ribs of equal width, with a mesh size of 50 mm. After passing through the middle screening plate 3.4, materials with a particle size of 50 mm to 150 mm pass through the middle discharge port onto the air injection belt. Pulverized coal or small particles with a particle size of less than 50 mm fall onto the bottom layer of the dynamic screen 3 and enter the coal preparation plant through lower discharge port 3.8.

[0043] like Figure 1As shown, the gangue identification device 4 is composed of a light source 4.1, a camera 4.2 and a host computer. The light source 4.1 is symmetrically arranged on both sides of the camera 4.2. The gangue identification device 4 is further subdivided into a first gangue identification device and a second gangue identification device. The two sets of gangue identification devices are provided with independent light sources and cameras, and the collected images are input into the same host computer for processing. The first gangue identification device is provided above the manipulator belt 7, and the second gangue identification device is provided above the air-spraying belt 9. The camera 4.2 in the gangue identification device is connected to the host computer, and the host computer is connected to the controller 5 by signal. The camera 4.2 collects images and sends the images to the host computer. The host computer completes the positioning and classification identification of the materials in the image, and encodes the detection information and sends it to the controller 5. The controller 5 controls the action mechanism to perform the sorting action.

[0044] The first gangue identification device and the second gangue identification device are both gangue identification devices, which include a light source and a camera. The light source is symmetrically arranged on both sides of the camera. The camera is connected to the host computer signal, and the host computer is connected to the controller signal.

[0045] The gangue recognition device uses a camera to capture images of the belt and materials in real time. The target detection algorithm preset in the host computer processes the images, locates the materials in the images, and identifies their categories. To further calculate the position of the target on the belt, the pixel coordinates (unit: pixel) in the pixel coordinate system are mapped to the real-world belt coordinate system (unit: mm) according to Equation 1 (e.g. Figure 3 Assume that the pixel coordinates in the image are ( u B , v B ), then the corresponding position in the belt coordinate system ( x B , y B )for:

[0046] (1)

[0047] Where, B is the belt type code. Different belt type codes correspond to different belt coordinate systems: the manipulator belt is represented by br , the air spray belt is expressed as ba .d Bx d By 、u BO 、v BO For B Coordinate transformation parameters in the belt-like coordinate system, d Bx A pixel is located at the lower edge of the corresponding belt coordinate system. x Length in the axial direction, d By A pixel is located at the lower edge of the corresponding belt coordinate system. y Length in the axial direction, (u BO , v BO ) represents the position of the pixel coordinate origin in the world coordinate system after the pixel coordinate is converted to the corresponding belt coordinate system. Specification: Belt coordinate system, the upper surface of the belt is xOy plane, the belt runs in the direction of y The belt surface is perpendicular to its running direction (the direction of belt width). x Axis, the direction perpendicular to the upper surface of the belt is z The coordinate systems of the robot belt and the air-jet belt are independent of each other.

[0048] like Figure 3 As shown in the figure, the target positioning is marked by the rectangular frame circumscribing the target outline, and the target position information in the image is marked with the coordinates of the upper left corner, lower right corner and center point of the rectangular frame. The coordinates of the upper left corner of the target in the image are expressed as ( u B1 , v B1 ), the coordinates of the lower right corner are expressed as ( u B2 , v B2 ), the center point coordinates are expressed as ( u B0 , v B0 ). The relationship between the center point coordinates and the upper left and lower right corner coordinates is as follows:

[0049] (2)

[0050] According to formula 1, the coordinates of the material positioning frame are mapped from the image coordinate system to the belt coordinate system. After the conversion, the coordinates of the three corresponding position points are ( x B1 , y B1 ), ( x B2 , y B2 ), ( x B0 , y B0 ). The material classification identification code is: 0-coal, 1-gangue.

[0051] like Figure 4-Figure 6 As shown, the gripper of the gantry manipulator 6 includes a gripper fixing frame 6.1, a gripper lead screw 6.2, a gripper guide rail 6.3, a lead screw slider 6.4, a guide rail base 6.5, a gripper motor 6.6, and a moving gripper 6.7 ( Figure 5 ), guide rail slider 6.8 and fixed claw 6.9 ( Figure 6). The mobile claw 6.7 is composed of three mobile claws, each claw 6.7.1 is fixed to the mobile claw fixing plate 6.7.2 through a threaded connection. The mobile claw fixing plate 6.7.1 is fixed to the screw slider 6.4 and the guide rail slider 6.8 through a threaded connection. The screw 6.2 and the gripper guide rail 6.3 are fixed to the gripper fixing frame 6.1 through a threaded connection with the guide rail base 6.5. The fixed claw 6.9 is fixed to the gripper fixing frame 6.1 through a threaded connection. The gripper is divided into two models according to the size of the gripper opening and closing: the small gripper (1# gripper) has a screw stroke of 50mm~250mm and is used to grab gangue with a particle size of ≤250mm. The large gripper (2# gripper) has a screw stroke of 50mm~400mm and is used to grab gangue with a particle size of 250mm~400mm. The gripper moves along the manipulator belt coordinate system. x direction to open and close.

[0052] like Figure 7-14 As shown, the whole array device 10 includes a vertical deflector 10.1, a deflector fixing member 10.2, a deflector connecting rod 10.3, a fixing buckle 10.4, and a whole array device fixing frame 10.5. The deflector fixing member 10.2 includes an elastic fixing ring 10.2.1, a hexagonal bolt 10.2.2, and a hexagonal nut 10.2.3. Figure 8 As shown, the deflector connecting rod 10.3 is a stepped shaft, and the left half shaft is symmetrical with the right half shaft. Figure 8 is the left half axis graph. Figure 10-11 As shown, the fixing buckle 10.4 ( Figure 9 ) is installed on the outermost shoulder of the deflector link 10.3 ( Figure 8 The fixing clip is fixed at the fixed position) and is fixed to the whole array device fixing frame 10.5 by T-bolts to prevent the guide plate connecting rod from axial movement. Figure 12-13 As shown, the deflector 10.1 and the deflector fixing member 10.2 are installed at the shaft shoulder in the middle of the deflector connecting rod 10.3 ( Figure 8 The guide plate and its fixing parts are fixed), one side of the guide plate is close to the shaft side where the diameter of the guide plate connecting rod increases, and the other side is clamped by the elastic fixing ring 10.2.1 and fastened by the hexagonal bolt 10.2.2 and the hexagonal nut 10.2.3 to prevent the guide plate from axial movement.

[0053] A screening method for a coal gangue double-belt combined dry separation system includes the following steps.

[0054] S100: The gangue material is fed into the dynamic screen 3. After screening by the dynamic screen 3, the material with a particle size ≥150 mm enters the manipulator belt 7 through the upper discharge port 3.5, the material with a particle size of 50 mm to 150 mm enters the air injection belt 9 through the middle discharge port, and the material with a particle size <50 mm enters the coal preparation plant through the lower discharge port 3.8.

[0055] S200: Coal and gangue with a particle size of ≥150mm enter the manipulator belt 7. The belt speed of the manipulator belt 7 ranges from 0.5m / s to 1m / s. The first coal gangue identification device detects the material and obtains the positioning coordinates of the material on the belt ( x br1 , y br1 ),( x br2 , y br2 ), ( x br0 , y br0 ) and category recognition results, when the target recognition result is coal, no further information processing is performed; when the target recognition result is gangue, x br2 - x br1 The value of replaces the particle size of the material along the width direction. If the value is ≤250mm, an action command is issued to the 1# gripper, otherwise an action command is issued to the 2# gripper.

[0056] According to the center point of the material y Coordinate value y br0 , determine the grabbing position and action time of the 1# or 2# claw, grab the gangue and put it into the gangue bin, and the coal falls into the coal bin along the belt movement;

[0057] In the robot belt coordinate system, the robot grasps y The position of the direction is fixed and can be moved along x Direction and z Direction movement; when the gangue moves along the belt to the robot y Grab position of direction y r At the same time, the manipulator grabs the gangue and puts it into the gangue bin, and the coal moves along the belt and falls into the coal bin; according to the center point of the material y Axis coordinates y br0 and formula Calculate the robot action delay, t mr is the manipulator action delay, t' is the time it takes for the manipulator to reach the grasping point from the initial position, and t p The time for the host computer to calculate the detection target and send the detection results is v r .

[0058] S300: Coal and gangue with a particle size of 50mm~150mm fall into the air-jet belt 9 through the middle-level discharge port 3.6 of the dynamic screen 3. The air-jet belt speed is ≥1m / s; the middle-level discharge port of the dynamic screen 3 is located directly above the drop zone of the entire array device 10. After falling, the materials are guided by their own gravity through the vertical guide plates and randomly fall into a certain channel, completing the channel arrangement.

[0059] S400: The material passes through the second gangue identification device and obtains the positioning coordinates of the material on the belt ( x ba1 , y ba1 ),( x ba2 , y ba2 ), ( x ba0 , y ba0 ) and category identification results. If the material is coal, it will fall directly into the coal bin; if the identification result is gangue, it will be blown into the gangue bin by the high-pressure gas blown out by the air-spray sorting mechanism 8 during the falling process.

[0060] Determine the air nozzle that performs the jet action according to the coordinates of the gangue: x coordinate[ x ba1 , x ba2 ] Determine the channel number and sub-channel interval where the gangue is located. If x ba1 and x ba2 are all located in the same sub-channel interval, the air nozzle corresponding to the channel performs the jet action; if x ba1 and x ba2 Located in different sub-channel intervals, the air nozzles corresponding to the two sub-channels and all the sub-channels between the two sub-channels all perform the jet action; according to the center point y coordinate y ba0 and formula Determine the air jet waiting time of the air jet sorting mechanism 8, and the position coordinates of the air nozzle in the belt running direction are y a , installed under the belt h a At, the air spray belt speed is v a .

[0061] Sorting example 1: Robot belt sorting:

[0062] like Figure 15 As shown in the figure, the material particle size is greater than 150mm and enters the robot belt 7 for sorting. In the example system, the robot belt speed is set to 0.5m / s, and the coordinate conversion parameter in the robot belt coordinate system is d brx =d bry =0.4,u br0 =0,v br0 =2000. After the first gangue identification device, the target identification result is gangue, and the pixel coordinates of the upper left corner and lower right corner of the material in the image are obtained [( u br1 , v br1 ), ( u br2 , v br2 )]=[(729,190), (1471,728)], calculate the positioning coordinates on the belt according to formula 1 [( x br1 , y br1 ), ( x br2 , y br2 ), ( x br0 , y br0 )]=[(291.6,1924), (588.4,1708.8), (440,1816.4)], particle size of the material along the bandwidth direction x br2 - x br1 =296.8mm>250mm, send action command to 2# gripper. y coordinate y br =3500, the time from the initial position to the grasping point is 1s, the detection time of a coal gangue detection algorithm is 38ms, according to the formula Calculation shows that the action delay of the 2# robot is 2.329s, and the 2# robot grabs the gangue and puts it into the gangue bin.

[0063] Sorting example 2: air-spray belt sorting:

[0064] like Figure 1 、 Figure 7 、 Figure 14As shown, the middle-level discharge port 3.6 of the dynamic screen machine 3 is located directly above the drop zone of the entire array device 10. During the falling process, the material falls into a channel formed by adjacent vertical guide plates under the "guidance" of the vertical guide plates 10.1 by its own gravity. When passing through the guide plate connecting rod 10.3, the stacked materials can be flattened on the belt due to the limitation of the connecting rod installation height, completing the channel arrangement. The example system is set up for three-channel sorting. The coordinate intervals (along the x-axis) of the three channels and their virtual sub-channels are shown in Table 1. Channel gaps are set between adjacent channels.

[0065] Table 1. Channel interval (coordinate unit: mm)

[0066]

[0067] A second gangue identification device is provided behind the arranging device 10, and an air-spray sorting mechanism 8 is provided at the end of the air-spray belt 9. In the example system, two air nozzles are provided for each channel and are coded. The coding rule is ab, where a is the channel number (1-3), and b is the air nozzle number in the channel (1 or 2). Each air nozzle corresponds to a virtual sub-channel.

[0068] like Figure 16 As shown in the figure, the material particle size is between 50mm and 150mm. Coal and gangue fall into the air-spraying belt through the middle discharge port 3.6 of the dynamic screen 3 and the drop zone of the whole array device 10. The air-spraying belt speed of the example system is 1m / s. The coordinate transformation parameters in the air-spraying belt coordinate system are , , The material passes through the second gangue identification device and detects two targets. Target 1 is coal and is not further processed; Target 2 is gangue. The pixel coordinates of the upper left and lower right corners of the image are [( u br1 , v br1 ), ( u br2 , v br2 )]=[(858,660), (1222,949)], calculate the positioning coordinates on the belt according to formula 1 [( x br1 , y br1 ), ( x br2 , y br2 ), ( x br0 , y br0)]=[(343.2,2736), (488.8,2620.4), (416,2678.2)], from the center point x coordinate x br0 The value of determines that the gangue is located in channel 2, x br1 and x br2 The value of determines that the gangue occupies the two sub-channels of channel 2, so the action signal is sent to the 2-1# and 2-2# gas nozzles. y br0 and formula Calculate the delay, the installation position of the gas nozzle is y a =4000mm, h a =30mm, the detection time of the target detection algorithm is 38ms.

[0069] A coal bunker is set near the end of the air-spraying belt 9, and a gangue bunker is set away from the belt. The coal blocks fall directly into the coal bunker, and the gangue is blown into the gangue bunker by the high-pressure gas blown out by the air nozzle during the falling process.

Claims

1. A double-belt combined dry separation system for coal gangue, characterized by: It includes a dynamic screening machine (3), a controller (5), a gantry manipulator (6), a manipulator belt (7), an air-spray sorting mechanism (8), an air-spray belt (9) and a gangue arranging device (10). The dynamic screening machine (3) is provided with an upper discharge port (3.5) for allowing materials with a particle size of ≥150 mm to pass through, a middle discharge port (3.6) for allowing materials with a particle size between 50 mm and 150 mm to pass through, and a lower discharge port (3.8) for allowing materials with a particle size of <50 mm to pass through; The upper discharge port (3.5) is connected to the manipulator belt (7), and the middle discharge port (3.6) is connected to the air-spraying belt (9). A first coal gangue identification device and a gantry manipulator (6) are arranged above the manipulator belt (7). The first coal gangue identification device identifies and distinguishes coal and gangue in the material. The gantry manipulator (6) picks the coal and gangue into the coal bin or gangue bin according to the identification result of the first coal gangue identification device. A coal gangue arranging device (10) is arranged at the front of the air-spraying belt (9). A second coal gangue identification device is arranged above the middle of the air-spraying belt (9). The second coal gangue identification device identifies and distinguishes coal and gangue in the material. The air-spraying belt (9) is divided into a plurality of channels according to the material channel of the arranging device, and each channel is further divided into a plurality of virtual sub-channels. A plurality of air-spraying sorting mechanisms (8) are arranged at the outlet of the multi-row material channel at the tail of the air-spraying belt (9), and each air-spraying sorting mechanism (8) corresponds to a virtual sub-channel of the air-spraying belt. The air-jet sorting mechanism sorts the coal and gangue into the coal bin or gangue bin respectively according to the recognition result of the second coal gangue recognition device. If the recognition result is gangue, the high-pressure gas blown by the air-jet sorting mechanism (8) is blown into the gangue bin during the falling process. According to the coordinates of gangue positioning ( x ba1 , y ba1 ), ( x ba2 , y ba2 ), ( x ba0 , y ba0 ) Determine the air nozzle that performs the jet action: According to the upper left corner of the gangue x coordinate x ba1 and the lower right corner x coordinate x ba2 Determine the channel number and sub-channel interval where the gangue is located. If x ba1 and x ba2 are all located in the same sub-channel interval, the air nozzle corresponding to the channel performs the jet action; if x ba1 and x ba2 Located in different sub-channel intervals, the air nozzles corresponding to the two sub-channels and all the sub-channels between the two sub-channels all perform jetting action; according to the center point of the gangue y coordinate y ba0 and formula Determine the air jet waiting time of the air jet sorting mechanism (8), and the position coordinates of the air jet nozzle in the belt running direction are y a , installed under the belt h a At, t p The time for the host computer to calculate the detection target and send the detection results is v a ; The first gangue identification device and the second gangue identification device are connected to the controller (5).

2. The coal gangue double belt combined dry separation system according to claim 1, characterized in that: The gantry manipulator (6) includes a gripper fixing frame (6.1), a gripper lead screw (6.2), a gripper guide rail (6.3), a lead screw slider (6.4), a guide rail base (6.5), a gripper motor (6.6), a movable gripper (6.7), a guide rail slider (6.8) and a fixed gripper (6.9), wherein the gripper lead screw (6.2) and the gripper guide rail (6.3) are mounted on the gripper fixing frame (6.1) via the guide rail base (6.5), the gripper lead screw (6.2) is driven by the gripper motor (6.6), the gripper guide rail (6.3) is symmetrically arranged on both sides of the gripper lead screw (6.2), a lead screw slider (6.4) is arranged on the gripper lead screw (6.2), and a gripper guide rail (6.3) is arranged on the gripper guide rail (6.3). A guide rail slider (6.8) is provided, and the same movable claw (6.7) is installed on the lead screw slider (6.4) and the guide rail slider (6.8). A fixed claw (6.9) is also installed at the bottom of the hand claw fixing frame (6.1). The movable claw (6.7) and the fixed claw (6.9) are symmetrically arranged. Two groups of hand grippers consisting of movable claws (6.7) and fixed claws (6.9) are arranged on the hand claw fixing frame (6.1), namely, 1# hand claw and 2# hand claw. The hand claw lead screw stroke of 1# hand claw is 50mm~250mm, and is used for grabbing gangue with a particle size of ≤250mm. The lead screw stroke of 2# hand claw is 50mm~400mm, and is used for grabbing gangue with a particle size of 250mm~400mm.

3. The coal gangue double belt combined dry separation system according to claim 1, characterized in that: The air jet sorting mechanism (8) includes an air nozzle controlled by a high-pressure air valve, and each air nozzle of the air jet sorting mechanism (8) is coded according to a coding rule of ab, where a is the channel number and b is the virtual sub-channel number; A coal bin is set near the end of the air-spraying belt, and a gangue bin is set away from the belt. If the material is coal, it will fall directly into the coal bin. If the material is gangue, it will be blown into the gangue bin by the high-pressure gas blown out by the air nozzle during the falling process.

4. The coal gangue double belt combined dry separation system according to claim 1, characterized in that: The array device (10) comprises vertical guide plates (10.1), guide plate fixing members (10.2), guide plate connecting rods (10.3), fixing buckles (10.4) and an array device fixing frame (10.5). Multiple groups of vertical guide plates (10.1) are arranged side by side. Funnel-shaped channels are formed from top to bottom between adjacent vertical guide plates (10.1). Guide plate connecting rods (10.3) are provided between the vertical guide plates (10.1). The guide plate connecting rods (10.3) are fixed to the guide plates (10.1) via the guide plate fixing members (10.2). Both ends of the guide plate connecting rods (10.3) are fixed to the array device fixing frame (10.5) via fixing buckles (10.4).

5. The coal gangue double belt combined dry separation system according to claim 4, characterized in that: The deflector fixing member (10.2) includes an elastic fixing retaining ring (10.2.1), a hexagonal bolt (10.2.2) and a hexagonal nut (10.2.3). The elastic fixing retaining ring (10.2.1) is a semicircular arc structure. Both ends of the semicircular arc structure are provided with extensions, and the extensions are provided with through holes. The hexagonal bolts (10.2.2) are provided in the through holes. The ends of the hexagonal bolts (10.2.2) are fastened by the hexagonal nuts (10.2.3).

6. The coal gangue double belt combined dry separation system according to claim 4, characterized in that: The middle-layer discharge port (3.6) of the dynamic screen (3) is located directly above the drop zone of the entire array device (10). After the materials fall, they are guided by the vertical guide plates under their own gravity and randomly fall into a channel formed by the vertical guide plates (10.1), thus realizing channel drop. When passing through the guide plate connecting rod (10.3), due to the installation height restriction of the guide plate connecting rod (10.3), the stacked materials are flattened on the belt, thus completing the channel arrangement.

7. A screening method for a double-belt combined dry separation system for coal gangue according to claim 2, characterized in that: The following steps are included: S100: The gangue material is fed into the dynamic screen (3). After screening by the dynamic screen (3), the material with a particle size of ≥150 mm enters the manipulator belt (7) through the upper discharge port (3.5), the material with a particle size of 50 mm to 150 mm enters the air injection belt (9) through the middle discharge port, and the material with a particle size of <50 mm enters the coal preparation plant through the lower discharge port (3.8); S200: Coal and gangue with a particle size of ≥150 mm enter the manipulator belt (7). The belt speed of the manipulator belt (7) ranges from 0.5 m / s to 1 m / s. The first coal gangue identification device detects the material and obtains the positioning coordinates of the material on the belt ( x br1 , y br1 ),( x br2 , y br2 ), ( x br0 , y br0 ) and category recognition results. When the recognition result is coal, no further information processing is performed; When the identification result is gangue, x br2 - x br1 The value of replaces the particle size of the material along the width direction. If the value is ≤250mm, an action command is issued to the 1# gripper, otherwise an action command is issued to the 2# gripper; S300: Coal and gangue with a particle size of 50 mm to 150 mm fall into the air-spraying belt (9) through the middle-layer discharge port (3.6) of the dynamic screen (3), and the air-spraying belt speed is ≥1 m / s; the middle-layer discharge port of the dynamic screen (3) is located directly above the drop zone of the entire array device (10). After falling, the material passes through the vertical guide plate under its own gravity and falls randomly into a certain channel, completing the channel arrangement; S400: The material passes through the second gangue identification device and obtains the positioning coordinates of the material on the belt ( x ba1 , y ba1 ), ( x ba2 , y ba2 ), ( x ba0 , y ba0 ) and the category recognition result. If the recognition result is coal, it will fall directly into the coal bin; if the recognition result is gangue, it will be blown into the gangue bin by the high-pressure gas blown out by the air-spray sorting mechanism (8) during the falling process.

8. The screening method of the coal gangue double belt combined dry separation system according to claim 7, characterized in that: In the step S200, according to the center point of the material y Coordinate value y br0 , determine the grabbing position and action time of the 1# or 2# claw, grab the gangue and put it into the gangue bin, and the coal falls into the coal bin along the belt movement; In the robot belt coordinate system, the robot grasps y The position of the direction is fixed and can be moved along x Direction and z Direction movement; when the gangue moves along the belt to the robot y Grab position of direction y r At the same time, the manipulator grabs the gangue and puts it into the gangue bin, and the coal moves along the belt and falls into the coal bin; according to the center point of the material y Axis coordinates y br0 and formula Calculate the robot action delay, t mr is the manipulator action delay, t' is the time it takes for the manipulator to reach the grasping point from the initial position, The time for the host computer to calculate the detection target and send the detection results is v r .

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