Coal screening equipment for open pit coal mining

Abstract

The invention provides coal screening equipment for open pit coal mining, and relates to the field of coal screening. The coal screening equipment comprises a screening box, a feeding port is formed in the top end of the screening box, a discharging port is formed in the bottom end of the screening box, and multiple layers of screening plates are arranged between the feeding port and the discharging port in the screening box at intervals in the height direction. The vibrating frame connected with the screen plate is driven by the cam mechanism to vibrate up and down, coal materials are vibrated and screened in the screen box, small coal materials fall downwards step by step through screen holes, and therefore the multi-stage screening procedure of the coal materials is automatically completed; the cleaning rings fixed in rows are driven by the first driving mechanism to rotate, coal materials adhering to the inner walls of the screen holes can be cleaned in time, meanwhile, the lead screw is driven by the control motor to rotate to drive the push plate to move in a reciprocating mode, and large coal materials staying at the top end of the screen plate are discharged in time through the discharging opening.

Description

Technical Field

[0001] This invention relates to the field of coal screening technology, and in particular to a coal screening device for open-pit coal mining. Background Technology

[0002] Coal, as a vital global energy source and industrial raw material, plays a crucial role in national economic development. Open-pit coal mining, due to its high efficiency and low cost, has become one of the main methods of coal extraction. In open-pit coal mining, coal screening is a critical step, directly affecting coal quality, grading, and subsequent processing. The main function of coal screening equipment is to classify the mined coal by particle size, separating coal products of different sizes to meet the needs of different users, while simultaneously removing impurities and improving coal quality. Common coal screening equipment includes drum screens, vibrating screens, and probability screens, which achieve coal screening and grading through different working principles and structural designs.

[0003] However, dust or wet, sticky particles in coal easily adhere to the inner wall of the screen holes, causing the screening efficiency to gradually decrease. Regular shutdowns for cleaning are necessary, which is time-consuming. If larger pieces of coal cannot pass through the screen holes and remain there, it can easily affect the passage of other smaller pieces of coal through the screen holes, thus causing the overall coal screening process to gradually decline. Therefore, a coal screening device for open-pit coal mining is needed to address the shortcomings of the existing equipment. Summary of the Invention

[0004] The purpose of this invention is to provide a coal screening device for open-pit coal mining, so as to solve the problems of dust or wet sticky particles easily adhering to the inner wall of the screen holes and timely discharge of larger coal materials.

[0005] This invention provides a coal screening device for open-pit coal mining, including a screen box. The top of the screen box has a feed inlet, and the bottom of the screen box has a discharge outlet. Inside the screen box, multiple screen plates are spaced apart along the height direction between the feed inlet and the discharge outlet. The outside of the screen box is provided with a vibrating frame fixedly connected to multiple screen plates. The screen box is provided with a cam mechanism for driving the vibrating frame to move up and down. Discharge outlets are provided on both sides of the screen box corresponding to the position of each screen plate. Each of the screen plates has multiple rows of screen holes, and each screen hole has a cleaning ring. The cleaning rings in each row of screen holes are sequentially fixedly connected by connecting rods. The screen plates have adjustment holes along the height direction corresponding to the connecting rods. The height of the adjustment holes is greater than the diameter of the connecting rods. The outside of the screen box is provided with a first driving mechanism for driving the connecting rods to rotate. Inside the screen box, a push plate is slidably arranged above each screen plate. Inside the screen plate, a lead screw that cooperates with the push plate for transmission is rotatably installed. The outside of the screen box is provided with a motor for driving the lead screw to rotate.

[0006] Furthermore, the diameter of the sieve holes in the multiple sieve plates gradually decreases from top to bottom.

[0007] Furthermore, the cam mechanism includes a first motor and a first camshaft and a second camshaft respectively disposed on the upper and lower sides of the vibration frame. The output end of the first motor is fixedly connected to the first camshaft. The ends of the first camshaft and the second camshaft are provided with synchronous pulleys. The synchronous pulleys on the first camshaft and the second camshaft are connected by a synchronous belt drive.

[0008] Furthermore, the sieve box is provided with vibration adjustment holes corresponding to the plurality of sieve plates respectively, and the connecting lugs on the sieve plates are fixedly connected to the vibration frame through the vibration adjustment holes, wherein the thickness of the connecting lugs is less than the height of the vibration adjustment holes.

[0009] Furthermore, the first driving mechanism includes a chain and a plurality of sprockets corresponding to each of the cleaning rings fixed in sequence. The sprockets are fixedly installed on the connecting rods of the cleaning rings at the ends. The plurality of sprockets are driven together and installed on the inner side of the chain. A second motor for driving the sprockets to rotate is fixedly installed on the screen box.

[0010] Furthermore, a guide rod parallel to the lead screw is rotatably installed inside the screen box, and one end of the push plate is slidably installed on the guide rod.

[0011] Furthermore, the bottom of the screen box is inclined from both sides toward the discharge port.

[0012] Furthermore, the height of the pusher plate is the same as the height of the discharge plate.

[0013] Furthermore, the diameter of the cleaning ring is the same as the diameter of the sieve hole on the corresponding sieve plate.

[0014] Furthermore, the top of the screen box is symmetrically provided with inlets on both sides, and each inlet is provided with a feed hopper, which is inclined outward.

[0015] The technical solution of this invention achieves the vibration screening of coal material inside the screen box by setting multiple layers of screen plates at intervals inside the screen box and using a cam mechanism to drive the vibrating frame connected to the screen plates to vibrate up and down. This allows smaller coal materials to fall down through the screen holes step by step, thereby automatically completing the multi-stage screening process of coal material. Cleaning rings are set in the screen holes of the screen plates and fixed in a row. The fixed cleaning rings are driven to rotate by the first drive mechanism, which can clean the coal material adhering to the inner wall of the screen holes in time. At the same time, by controlling the motor to drive the screw to rotate, the push plate moves back and forth, and larger coal materials remaining at the top of the screen plate are discharged in time through the discharge port. Attached Figure Description

[0016] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is a schematic diagram of the structure of the present invention from another perspective; Figure 3 This is a schematic diagram of the sieve box structure of the present invention; Figure 4 This is a schematic diagram of a partial cross-sectional structure of the sieve box of the present invention; Figure 5 This is a schematic diagram of the connection structure between the vibrating frame and the sieve plate of the present invention; Figure 6 This is a schematic diagram of the sieve plate portion of the present invention; Figure 7 This is a schematic diagram of the structure of the vibration frame and cam mechanism of the present invention; Figure 8 This is a schematic diagram of the disassembly structure of the cleaning ring and sieve plate in this invention.

[0018] Explanation of reference numerals in the attached drawings: 1-Screen box, 101-Feed hopper, 102-Discharge port, 103-Support block, 104-Vibration adjustment hole, 2-Screen plate, 201-Screen hole, 202-Adjustment hole, 203-Connecting ear plate, 3-Vibration frame, 4-First camshaft, 5-Second camshaft, 6-Synchronous pulley, 7-Synchronous belt, 8-First motor, 9-Push plate, 10-Screw screw, 11-Third motor, 12-Guide rod, 13-Cleaning ring, 14-Connecting rod, 15-Sprocket, 16-Chain, 17-Second motor. Detailed Implementation

[0019] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0021] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified. Furthermore, the terms "installed," "connected," and "linked" should be interpreted broadly; for example, they may refer to a fixed connection, a detachable connection, or an integral connection; they may refer to a mechanical connection or an electrical connection; they may refer to a direct connection or an indirect connection through an intermediate medium; and they may refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0022] Example 1 like Figures 1-8As shown, this invention provides a coal screening device for open-pit coal mining, including a screen box 1. The screen box 1 has symmetrical feed inlets on both sides of its top. A feed hopper 101 is provided at each feed inlet, and the feed hopper 101 is inclined outwards. A discharge outlet is provided at the bottom of the screen box 1. Multiple layers of screen plates 201 are spaced along the height direction between the feed inlets and discharge outlets inside the screen box 1. The diameter of the screen holes in the multiple layers of screen plates 201 gradually decreases from top to bottom. In this embodiment, the screen box 1 has three layers of screen plates 201 for easy differentiation. The screens are named from top to bottom as the first screen plate, the second screen plate, and the third screen plate. The outer side of the screen box 1 is provided with a vibrating frame 3 that is fixedly connected to the multi-layer screen plate 201. The screen box 1 is provided with vibration adjustment holes 104 corresponding to the multi-layer screen plate 201. The connecting ear plate 203 on the screen plate 201 is fixedly connected to the vibrating frame 3 through the vibration adjustment hole 104. The thickness of the connecting ear plate 203 is less than the height of the vibration adjustment hole 104, so that the screen plate 201 can move up and down within the height range of the vibration adjustment hole 104.

[0023] In order to enable the multi-layer screen plate 201 to move up and down through the vibrating frame 3 to screen the coal, a cam mechanism is provided on the screen box 1 to drive the vibrating frame 3 to move up and down. The cam mechanism includes a first motor 8 and a first camshaft 4 and a second camshaft 5 respectively set on the upper and lower sides of the vibrating frame 3. Two sets of support blocks 103 are fixedly installed at the top of the screen box 1. The first camshaft 4 and the second camshaft 5 are rotatably installed between each set of support blocks 103. The output end of the first motor 8 is fixedly connected to the first camshaft 4. The ends of the first camshaft 4 and the second camshaft 5 are provided with synchronous pulleys 6. The synchronous pulleys 6 on the first camshaft 4 and the second camshaft 5 are connected by a synchronous belt 7. When the distal end of the first camshaft 4 is in contact with the upper surface of the vibrating frame 3, the proximal end of the second camshaft 5 is in contact with the lower surface of the vibrating frame 3. During operation: The first motor 8 is started, driving the first camshaft 4 to rotate, causing the synchronous pulley 6 to rotate synchronously. Under the action of the synchronous belt 7, the second camshaft 5 is driven to rotate synchronously. Since the vibrating frame 3 is located between the first camshaft 4 and the second camshaft 5, and when the distal end of the first camshaft 4 is in contact with the upper surface of the vibrating frame 3, the proximal end of the second camshaft 5 is in contact with the lower surface of the vibrating frame 3, thereby causing the vibrating frame 3 to drive the multi-layer screen plate 201 to vibrate up and down, realizing the vibration screening of coal inside the screen box 1, so that the coal falls down through the screen holes step by step, thereby automatically completing the multi-screening process of coal and improving screening efficiency. The bottom of the screen box 1 is inclined from both sides towards the discharge port, so that the finally screened coal can be automatically discharged from the discharge port.

[0024] To ensure timely discharge of large coal pieces screened by the screen plates 201 from the screen box 1, discharge ports 102 are provided on both sides of the screen box 1 corresponding to the position of each screen plate 201. Inside the screen box 1, a push plate 9 is slidably mounted above each screen plate 201. Inside the screen plate 201, a lead screw 10 is rotatably mounted and drives the push plate 9. A third motor 11 is provided on the outside of the screen box 1 to drive the lead screw 10 to rotate. Inside the screen box 1, on the side away from the lead screw 10, a guide parallel to the lead screw 10 is rotatably mounted. One end of the push plate 9 is slidably mounted on the guide rod 12. The rotation of the screw 10 can drive the push plate 9 to move and push the large pieces of coal on the screen plate 201 to the discharge port 102. The height of the push plate 9 is the same as the height of the discharge. Since the discharge port 102 is symmetrically arranged, the push plate 9 can discharge the coal from the discharge ports 102 on both the front and rear sides by moving back and forth (when the proximal end of the second camshaft 5 is in contact with the lower surface of the vibrating frame 3, the upper surface of the screen plate 201 is flush with the bottom end of the discharge port 102).

[0025] Each screen plate 201 has multiple rows of screen holes, and each screen hole has a cleaning ring 13. The cleaning ring 13 is circular, and its diameter is the same as the diameter of the corresponding screen hole on the screen plate 201. The cleaning ring 13 can be housed inside the screen hole without affecting the screening of coal. When the cleaning ring 13 rotates, it can scrape off the coal adhering to the screen hole, thereby clearing the screen hole. The corresponding cleaning rings 13 in each row of screen holes are fixedly connected by connecting rods 14. The screen plate 201 has adjustment holes 202 along the height direction corresponding to the connecting rods 14. The height of the adjustment holes 202 is greater than the diameter of the connecting rods 14, so that the screen plate 201 will not interfere with the cleaning rings 13 when it vibrates up and down. The outside of the screen box 1 is provided with a first drive mechanism for driving the connecting rods 14 to rotate. The mechanism includes a chain 16 and multiple sprockets 15 corresponding to cleaning rings 13 fixed in sequence in each column. Sprockets 15 are fixedly installed on the connecting rods 14 of the cleaning rings 13 at the ends. Multiple sprockets 15 are installed inside the chain 16 for common transmission, so that the chain 16 can drive multiple sprockets 15 to rotate simultaneously. A second motor 17 for driving the sprockets 15 to rotate is fixedly installed on the screen box 1. When the second motor 17 starts, it drives the sprockets 15 to rotate. Under the action of the chain 16, the cleaning rings 13 rotate inside the screen holes to clean the coal inside the screen holes and make it fall below the screen plate 201, so as to avoid the screen holes being blocked by sticky coal, thereby maintaining the screening effect of the screen plate 201, maintaining the screening efficiency of the screen plate 201, and reducing the number of times the screen plate 201 needs to be replaced.

[0026] Working principle: In operation, coal is first introduced through the feed hopper 101. The coal slides to the top of the first screen plate, and the first motor 8 is started, driving the first camshaft 4 to rotate, causing the synchronous pulley 6 to rotate synchronously. Under the action of the synchronous belt 7, the second camshaft 5 is driven to rotate. Since the vibrating frame 3 is located between the first camshaft 4 and the second camshaft 5, and when the distal end of the first camshaft 4 is in contact with the upper surface of the vibrating frame 3, the proximal end of the second camshaft 5 is in contact with the lower surface of the vibrating frame 3, thereby causing the vibrating frame 3 to vibrate up and down. The vibrating frame 3 drives the screen plate 201 to vibrate longitudinally through the connecting ear plate 203, so that the three screen plates 201 sequentially screen the coal. When a large amount of fine coal material adheres to the inside of the screen holes, the vibration of the screen plate 201 is stopped, the second motor 17 is started, and the sprocket 15 is driven to rotate. This causes multiple sprockets 15 to rotate synchronously under the drive of the chain 16, thereby causing the cleaning ring 13 to rotate inside the screen holes to clean the coal material inside the screen holes and make it fall below the screen plate 201. In addition, when a large amount of larger coal material accumulates on the screen plate 201, the third motor 11 is started to drive the lead screw 10 to rotate. In turn, the lead screw 10 drives the push plate 9 to move horizontally along the inner side of the screen box 1. The push plate 9 pushes the coal material on each screen plate 201 to the discharge port 102, so that it slides down from the discharge pipe in a unified and classified manner.

[0027] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A coal screening device for open-pit coal mining, characterized in that, The screen box includes a feed inlet at the top and a discharge outlet at the bottom. Inside the screen box, multiple screen plates are spaced along the height between the feed inlet and the discharge outlet. A vibrating frame is fixedly connected to the multiple screen plates on the outside of the screen box. A cam mechanism is provided on the screen box to drive the vibrating frame to move up and down. Discharge outlets are provided on both sides of the screen box corresponding to the position of each screen plate. Each of the screen plates has multiple rows of screen holes, and each screen hole has a cleaning ring. The cleaning rings in each row of screen holes are sequentially fixedly connected by connecting rods. The screen plates have adjustment holes along the height direction corresponding to the connecting rods. The height of the adjustment holes is greater than the diameter of the connecting rods. The outside of the screen box is provided with a first driving mechanism for driving the connecting rods to rotate. Inside the screen box, a push plate is slidably arranged above each screen plate. Inside the screen plate, a lead screw that cooperates with the push plate for transmission is rotatably installed. The outside of the screen box is provided with a motor for driving the lead screw to rotate.

2. The coal screening equipment for open-pit coal mining according to claim 1, characterized in that, The diameter of the sieve holes in the multiple sieve plates gradually decreases from top to bottom.

3. The coal screening equipment for open-pit coal mining according to claim 1, characterized in that, The cam mechanism includes a first motor and a first camshaft and a second camshaft respectively disposed on the upper and lower sides of the vibration frame. The output end of the first motor is fixedly connected to the first camshaft. Both the ends of the first camshaft and the second camshaft are provided with synchronous pulleys. The synchronous pulleys on the first camshaft and the second camshaft are connected by a synchronous belt drive.

4. The coal screening equipment for open-pit coal mining according to claim 1, characterized in that, The sieve box has vibration adjustment holes corresponding to the multiple sieve plates. The connecting lugs on the sieve plates are fixedly connected to the vibration frame through the vibration adjustment holes. The thickness of the connecting lugs is less than the height of the vibration adjustment holes.

5. The coal screening equipment for open-pit coal mining according to claim 1, characterized in that, The first driving mechanism includes a chain and a plurality of sprockets corresponding to each cleaning ring fixed in sequence. The sprockets are fixedly installed on the connecting rods of the cleaning rings at the ends. The plurality of sprockets are driven together and installed on the inner side of the chain. A second motor for driving the sprockets to rotate is fixedly installed on the screen box.

6. The coal screening equipment for open-pit coal mining according to claim 1, characterized in that, The screen box is rotatably mounted with a guide rod parallel to the lead screw, and one end of the push plate is slidably mounted on the guide rod.

7. The coal screening equipment for open-pit coal mining according to claim 1, characterized in that, The bottom of the screen box is inclined from both sides toward the discharge port.

8. The coal screening equipment for open-pit coal mining according to claim 1, characterized in that, The height of the pusher plate is the same as the height of the discharge plate.

9. The coal screening equipment for open-pit coal mining according to claim 1, characterized in that, The diameter of the cleaning ring is the same as the diameter of the sieve hole on the corresponding sieve plate.

10. The coal screening equipment for open-pit coal mining according to claim 1, characterized in that, The screen box has symmetrical feed inlets on both sides of its top, and each feed inlet has a feed hopper that is tilted outwards.

Images