A silo unloading device with a weighing mechanism

Abstract

The application discloses a kind of silo unloading device with weighing mechanism, belong to solid particle, powder automatic batching equipment technical field, including support, screw conveying mechanism, feed hopper, self-driven arch breaking device, primary metering weighing mechanism, negative pressure transfer pipeline, secondary re-weighing premixing mechanism, discharge flow self-adaptive adjusting mechanism, cylinder drive emergency unloading mechanism and reaction kettle;Self-excited vibration arch breaking structure of linkage screw main shaft is set in feed hopper, reciprocating vibration arch breaking is realized by relying on screw blade to push ball head to cooperate torsional spring, without independent driving motor;Material is sent into re-weighing hopper by negative pressure airtight after being roughly weighed by primary metering hopper, and built-in rotating raking plate in re-weighing hopper realizes material scattering premixing and secondary weighing verification;Spring buffer adjusting plate is set at screw discharge end to self-adaptively adjust discharge flow.The application solves the defects of high cost, large measurement error, poor material mixing, complicated cleaning and the like of existing equipment arch breaking mechanism.

Description

Technical Field

[0001] This invention relates to the technical field of automated batching and conveying equipment for powder and granular solid materials, and specifically to a silo unloading device with a weighing mechanism. Background Technology

[0002] In the production processes of fine chemicals, pharmaceutical intermediates, polymer materials, food additives, and inorganic fillers, many processes require various solid particles and powdered raw materials to be mixed in a fixed mass ratio and then fed into a reaction vessel for dissolution, synthesis, and catalytic reaction. The material unloading device with a weighing mechanism is the core equipment at the front end of the production line. The accuracy of batching, the smoothness of material discharge, the uniformity of material mixing, and the stability of equipment operation directly determine the finished product qualification rate and production efficiency.

[0003] A patent publication number CN204453889U, entitled "A Novel Cement Material Metering and Conveying Device," was found. The device specifically discloses a novel cement material metering and conveying device, comprising a material tank, a guide hood, a screw conveyor, a weighing scale, and a discharge hopper connected in sequence. The material tank is a metering tank body, which includes, from top to bottom, a top-to-bottom connected anti-jamming feeding device, a material interception device, a feeding and unloading anti-leaking device, the tank body, and an anti-jamming unloading device. The tank body is supported on a weighing device. A bulwark vibration anti-blocking device is installed on each side of the top surface of the tank body, and a volume detection device is installed inside. A powder anti-blocking loosening device is also installed in the lower part of the tank body, driven by an external anti-blocking controller. A detachable sieve plate is installed at the bottom of the weighing scale, and multiple through holes are evenly distributed on the surface of the sieve plate. In the aforementioned novel cement material metering and conveying device, the number of volume detection devices is three, and one set of powder anti-blocking loosening devices and one set of anti-blocking controllers are installed on each side. An automatic valve is also provided between the weighing scale and the sieve plate.

[0004] A patent publication number CN218707299U was found, entitled "A Weighing and Batching System Loading Station Silo," which specifically discloses a weighing and batching system loading station silo, including a silo and a load-bearing box. At least three silos are provided. A feed inlet is installed at the top of each silo, and a discharge pipe is installed at the bottom of each silo. A first electric valve is installed on the discharge pipe. A guide pipe is installed at the top of the load-bearing box, and the silos are connected to the guide pipe via the discharge pipe. An observation window with graduation marks is installed on the side of each silo. A load-bearing device is installed inside the load-bearing box, and a conveying pipe is installed on one side of the load-bearing box. A second electric valve is installed inside the conveying pipe, and the discharge pipe is connected to the guide pipe. The conveying pipe is inclined on the load-bearing box.

[0005] Analysis of the above-mentioned publicly available materials and in combination with existing technologies reveals the following shortcomings: the silo is prone to blockage during material feeding, the single-time weighing error is large, and the discharge flow rate of the screw conveyor cannot be dynamically and adaptively adjusted. Summary of the Invention

[0006] In view of this, the present invention provides a silo unloading device with a weighing mechanism, which not only automatically drives the arch-breaking device, significantly reducing equipment manufacturing costs, but also improves both batching accuracy and material mixing uniformity. Furthermore, the flexible adaptive discharge adjustment mechanism enables dynamic fine-tuning of the flow rate, greatly improving weighing stability.

[0007] To address the aforementioned technical problems, this invention provides a silo unloading device with a weighing mechanism, comprising a support frame. The support frame is equipped with a screw conveyor mechanism, a feeding hopper, a self-driven arch-breaking device, a primary metering mechanism, a negative pressure conveying pipeline, a re-weighing premixing mechanism, a discharge flow rate regulating mechanism, an emergency unloading mechanism, and a reaction vessel. The screw conveyor mechanism includes a screw conveyor housing, a first motor, a reducer, a conveying shaft, and screw blades; the feeding hopper is connected to the top of the screw conveyor housing. The self-driven arch-breaking device is located inside the feeding hopper and includes a support rod, a torsion spring, a connecting rod assembly, and a turning ball head, which engages with the screw groove of the screw blades. The primary metering mechanism includes a metering hopper and a first weighing device; the bottom of the metering hopper is connected to the negative pressure conveying pipeline. The re-weighing premixing mechanism includes a re-weighing hopper, a second weighing device, a second motor, and a turning plate with grate holes; the negative pressure conveying pipeline connects to the re-weighing hopper, and the bottom of the re-weighing hopper is connected to the reaction vessel.

[0008] Furthermore, the discharge flow rate adjustment mechanism includes a fixed lug, a guide rod, a spring, a baffle, and an adjustment plate; the emergency unloading mechanism includes an emergency support plate, a telescopic rod, a connecting plate, and a drive cylinder.

[0009] Furthermore, the self-driven arch-breaking device is equipped with two symmetrical support rods, each support rod is independently equipped with a set of torsion springs, and the two ends of the torsion springs are respectively pressed against the support rod and the inner wall of the feed hopper; the lower end of the support rods are connected to a connecting sleeve, and the lower end of the connecting sleeve is threaded with an adjusting cylinder with a locking bolt. The first connecting rod is slidably installed inside the adjusting cylinder, and the bottom end of the first connecting rod is detachably installed with a toggle ball head; the upper end of the connecting sleeve is connected to a second connecting rod, and the top end of the second connecting rod is equipped with an L-shaped toggle frame that extends into the material area of ​​the feed hopper; the toggle ball head is a polyurethane matrix with a ceramic wear-resistant coating structure, and the torsion spring is made of high-temperature resistant chromium vanadium spring steel and sprayed with an anti-corrosion epoxy layer.

[0010] Furthermore, in the aforementioned screw conveyor mechanism, the first motor is a variable frequency servo motor, and the reducer is a planetary gear reducer with a reduction ratio range of 1:20 to 1:60; the conveying shaft and the screw blades are fully welded and fixed, and the single-sided gap between the outer edge of the screw blades and the inner wall of the screw conveyor housing is controlled at 1.5mm to 3mm; the screw conveyor housing, feeding hopper, metering hopper, and weighing hopper are made of 304 stainless steel or 316L medical stainless steel, and the inner wall of the hopper is mirror polished.

[0011] Furthermore, the output end of the second motor of the re-weighing premixing mechanism is sealed and extends into the re-weighing hopper to form a rotating shaft. Four inclined material-pushing plates of 40° to 50° are detachably installed along the circumference of the rotating shaft. Rectangular grate holes are opened at equal intervals on the material-pushing plates, and the width of the grate holes is greater than 1.2 times the maximum particle diameter of the material. The side wall of the re-weighing hopper is connected to a negative pressure pipe, which is connected to an air compressor. Both the negative pressure conveying pipe and the inner wall of the re-weighing hopper are coated with an antistatic polyurethane coating with a thickness of 0.2 to 0.5 mm.

[0012] Furthermore, both the first and second weighing devices are high-precision weighing sensors with multi-point cantilever beams, and their signals are synchronously connected to the PLC control system. The PLC has built-in multiple control logics, including two-level weighing data comparison, dynamic automatic material replenishment, audible and visual alarms for weight deviation, and production data storage and export, which can record the material ratio data of each batch in real time.

[0013] Furthermore, the spring of the discharge flow rate adjustment mechanism is a replaceable cylindrical compression spring with a wire diameter of 1.5mm to 5mm to adapt to materials of different densities; a wear-resistant rubber buffer pad is attached to the side of the adjustment plate that is in contact with the discharge end; the two ends of the spring press against the baffle and the fixing ear respectively, and the adjustment plate is automatically opened by the pushing force of the material. When there is no material, the spring rebounds and narrows the discharge cross section, so as to realize the adaptive adjustment of the flow rate.

[0014] Furthermore, the emergency unloading mechanism has an arc-shaped support plate with a high-chromium wear-resistant liner bonded to the inner arc surface and annular sealing strips on both sides; a connecting plate is welded to the lower end of the emergency support plate, and the connecting plate is rigidly connected to the horizontal telescopic rod. The cylinder drives the telescopic rod to move horizontally to control the opening and closing of the unloading port; during normal production, the sealing strip is attached to the bottom unloading port of the spiral conveyor shell to prevent dust leakage and material seepage.

[0015] Furthermore, the entire machine is equipped with a complete set of intrinsically safe explosion-proof electrical assemblies. The first motor, the second motor, the solenoid valve, the weighing sensor, and the PLC controller are all explosion-proof components. The bracket, the screw conveyor shell, each hopper, and the negative pressure pipe are connected by anti-static grounding wires. The grounding resistance of the entire machine is controlled within 4Ω, making it suitable for continuous batching production of flammable and explosive powders in the chemical and pharmaceutical industries.

[0016] The beneficial effects of the above-described technical solution of the present invention are as follows: 1. Solve the problems of existing feeding hopper arch breaking devices that require independent motor drive, resulting in high equipment cost, many parts, and high failure rate, and realize arch breaking by using the power linkage of the screw conveyor main shaft for self-excited vibration, without the need for an additional drive source.

[0017] 2. Solve the problems of large single-stage weighing and metering errors, inability to verify material conveying losses, and poor mixing effect of multi-raw material layering and stacking, and realize the integration of single-stage weighing and metering + negative pressure transfer + re-weighing and secondary verification + synchronous dispersing and premixing in the re-weighing bin.

[0018] 3. To solve the problems of the screw conveyor's discharge flow rate not being able to be adaptively fine-tuned and the weighing data being interfered with by material impact, an elastic adjustable discharge baffle is set up to dynamically change the discharge cross section, buffer material impact, and improve batching accuracy.

[0019] 4. To solve the problems of no emergency unloading channel after equipment blockage failure, time-consuming and material-intensive disassembly and cleaning, and dust pollution, an emergency pallet unloading mechanism driven by a cylinder is added to quickly discharge the stuck material in the event of a failure. Attached Figure Description

[0020] Figure 1 This is a front view of the overall assembly structure of the silo unloading device with a weighing mechanism according to the present invention. Figure 2 for Figure 1 Enlarged structural diagram of section A in the middle; Figure 3 for Figure 1 A structural diagram from another perspective; Figure 4 for Figure 3 Enlarged view of section B; Figure 5 This is a schematic diagram of the connection structure between the spiral conveyor shell and the metering hopper of the present invention; Figure 6 This is a partial enlarged view of the support rod, torsion spring, and connecting assembly of the present invention; Figure 7 This is a schematic diagram of the internal structure of the weighing hopper; Figure 8 This is a schematic diagram of the structure of the spiral shaft, spiral blades and self-driven arch-breaking device of the present invention.

[0021] In the diagram: 1. Support frame; 2. Screw conveyor housing; 3. Reducer; 4. First motor; 5. Feed hopper; 6. Measuring hopper; 7. First weighing device; 8. Negative pressure conveying pipeline; 9. Re-weighing hopper; 10. Negative pressure pipe; 11. Second motor; 12. Second weighing device; 13. Reactor; 14. Conveying shaft; 15. Fixing lug; 16. Guide rod; 17. Spring; 18. Baffle; 19. Adjusting plate; 20. Emergency support plate; 21. Telescopic rod; 22. Connecting plate; 23. Screw blade; 51. Support rod; 52. Torsion spring; 53. Connecting sleeve; 54. Adjusting cylinder; 55. First connecting rod; 56. Second connecting rod; 57. Actuating frame; 58. Actuating ball head; 91. Rotating shaft; 92. Feeding plate; 93. Grate bar hole. Detailed Implementation

[0022] The following describes the overall structure of the silo unloading device with a weighing mechanism corresponding to this invention, as follows: Figures 1 to 8 As shown, the technical solution of the present invention is described in a complete and detailed manner. Those skilled in the art of equipment manufacturing and automated batching processes can completely replicate this device based on the content of this paragraph. This embodiment is only used to illustrate the present invention and is not intended to limit the scope of protection of the present invention.

[0023] Example 1 A silo unloading device with a weighing mechanism includes a support 1, on which a screw conveyor mechanism, a feed hopper 5, a self-driven arch-breaking device, a primary metering mechanism, a negative pressure conveying pipeline 8, a re-weighing premixing mechanism, a discharge flow rate regulating mechanism, an emergency unloading mechanism, and a reaction vessel 13 are mounted; the screw conveyor mechanism includes a screw conveyor housing 2, a first motor 4, a reducer 3, a conveying shaft 14, and screw blades 23, with the feed hopper 5 connected to the top of the screw conveyor housing 2; the self-driven arch-breaking device... The device is located inside the feed hopper 5 and includes a support rod 51, a torsion spring 52, a connecting rod assembly, and a pusher ball head 58, which is engaged in the screw groove of the spiral blade 23. The primary metering mechanism includes a metering hopper 6 and a first weighing device 7, with the bottom of the metering hopper 6 connected to a negative pressure conveying pipe 8. The re-weighing premixing mechanism includes a re-weighing hopper 9, a second weighing device 12, a second motor 11, and a pusher plate 92 with grate holes 93. The negative pressure conveying pipe 8 is connected to the re-weighing hopper 9, and the bottom of the re-weighing hopper 9 is connected to the reaction vessel 13.

[0024] In this embodiment, a spiral conveyor housing 2 is horizontally arranged on the upper layer of the support 1. A variable frequency servo motor 4 and a planetary gear reducer are mounted on the outer left side of the spiral conveyor housing 2. The output end of the motor is rigidly connected to the input shaft of the reducer 3. The output end of the reducer 3 is coaxially fixed to a conveyor shaft 14 that horizontally penetrates the inside of the spiral conveyor housing 2. The top opening of the spiral conveyor housing 2 is sealed and connected to the bottom of the feed hopper 5. The feed hopper 5 is a cone-shaped hopper that is wider at the top and narrower at the bottom. A removable sealing cover is installed on the top. The cover has a reserved explosion-proof feeding port and a dust removal docking interface to meet the requirements of clean and explosion-proof workshops. The feed hopper 5, metering hopper 6, and weighing hopper 9 are all made of 304 stainless steel or 316L medical-grade stainless steel plates. The inner wall of the hopper is mirror polished, which greatly reduces the probability of powder and granular materials adhering to the inner wall.

[0025] A primary weighing hopper 6 is located directly below the discharge end of the screw conveyor shell 2. The weighing hopper 6 is supported on a multi-point cantilever beam high-precision first weighing device 7. A two-position five-way pneumatic unloading solenoid valve is installed on the bottom flange of the weighing hopper 6. A fluororubber high-temperature resistant sealing gasket is installed at the flange connection of the solenoid valve. The outlet of the solenoid valve is sealed and connected to the negative pressure conveying pipeline 8. The material discharged from the weighing hopper 6 is transferred in a closed negative pressure system. The end of the negative pressure conveying pipeline 8 is connected to the top inlet of the weighing hopper 9. The side wall of the weighing hopper 9 is connected to a negative pressure pipe 10. The negative pressure pipe 10 is connected to an industrial air compressor. The air compressor continuously extracts air from the inside of the weighing hopper 9, creating a negative pressure environment between the pipeline and the inner cavity of the weighing hopper 9, thus achieving dust-free and closed material conveying. The inner wall of the negative pressure conveying pipeline 8 and the inner wall of the weighing hopper 9 are coated with an anti-static polyurethane coating with a thickness of 0.2mm to 0.5mm to avoid material loss caused by electrostatic adsorption of powder. The system is equipped with an additional pulse backflushing unit. The pulse pipeline is connected in parallel to the outer wall of the negative pressure conveying pipeline 8. The PLC automatically triggers pulse purging according to the preset cycle to regularly clean the fine powder adhering to the pipe wall.

[0026] Example 2 The discharge flow rate adjustment mechanism includes a fixed lug 15, a guide rod 16, a spring 17, a baffle 18, and an adjustment plate 19; the emergency unloading mechanism includes an emergency support plate 20, a telescopic rod 21, a connecting plate 22, and a drive cylinder.

[0027] In this embodiment, the outer wall of the discharge end of the spiral conveyor shell 2 is integrally formed with a fixing ear 15. The fixing ear 15 has a horizontal through-hole, and a smooth guide rod 16 that can slide freely is inserted inside the through-hole. A vertical adjustment plate 19 is fixed to one end of the guide rod 16 near the hopper. A wear-resistant rubber buffer pad is attached to one side of the adjustment plate 19 that is in contact with the discharge end face. A circular limit baffle 18 is threaded and locked to the outer end of the guide rod 16. A cylindrical compression spring 17 is fitted on the outside of the guide rod 16. The two ends of the spring 17 press against the baffle 18 and the outer wall of the fixing ear 15, respectively. The elastic force provided by the spring 17 can be changed to different wire diameter specifications from 1.5mm to 5mm according to the material density.

[0028] Example 3 The self-driven arch-breaking device is equipped with two symmetrical support rods 51, each support rod 51 is independently equipped with a set of torsion springs 52, and the two ends of the torsion springs 52 respectively abut against the support rod 51 and the inner wall of the feed hopper 5; the lower ends of the support rods 51 are connected to a connecting sleeve 53, and the lower end of the connecting sleeve 53 is threaded with an adjusting cylinder 54 with a locking bolt. The first connecting rod 55 is slidably installed inside the adjusting cylinder 54, and the bottom end of the first connecting rod 55 is detachably installed with a toggle ball head 58; the upper end of the connecting sleeve 53 is connected to a second connecting rod 56, and the top end of the second connecting rod 56 is provided with an L-shaped toggle frame 57 that extends into the material area of ​​the feed hopper 5; the toggle ball head 58 is a polyurethane matrix with a ceramic wear-resistant coating structure, and the torsion springs 52 are made of high-temperature chromium vanadium spring steel and sprayed with an anti-corrosion epoxy layer.

[0029] In this embodiment, the inner cavity of the feed hopper 5 is equipped with a self-driven arch-breaking device. The entire arch-breaking structure includes two symmetrically arranged support rods 51. The upper ends of the support rods 51 are hinged to the upper inner wall of the feed hopper 5 by pins. Each support rod 51 is equipped with a set of high-temperature resistant chromium vanadium spring steel torsion springs 52. The surface of the torsion springs 52 is coated with a corrosion-resistant epoxy anti-rust layer. The two ends of the torsion springs 52 are respectively pressed against the outer wall of the support rods 51 and the inner wall of the feed hopper 5. Under normal conditions, the entire arch-breaking assembly is lifted upward by the tension of the torsion springs 52. The lower ends of the two support rods 51 are rigidly connected to an integrated connecting sleeve 53. The lower end of the connecting sleeve 53 has an internal thread, which is matched with the adjusting cylinder 54. The side wall of the adjusting cylinder 54 has a radial locking thread hole, and a locking bolt is fitted inside the hole. The first connecting rod 55 is vertically slidably mounted inside the adjusting cylinder 54. Loosening the locking bolt allows the extension length of the first connecting rod 55 to be adjusted up and down, thereby changing the depth of the bottom actuating ball head 58 into the screw groove of the spiral blade 23. After adjustment, tighten the bolt to lock the position. The bottom thread of the first connecting rod 55 can be detachably installed with the actuating ball head 58. The actuating ball head 58 is made of polyurethane spherical matrix, and the entire matrix is ​​covered with a wear-resistant ceramic coating, which can withstand long-term friction wear with the spiral blade 23. The upper end of the connecting sleeve 53 is vertically welded upward to the second connecting rod 56. The top of the second connecting rod 56 is horizontally fixed with an L-shaped actuating frame 57. The actuating frame 57 extends horizontally to the material accumulation area in the middle and lower part of the feed hopper 5, and can directly contact the accumulated agglomerated and arched material. During equipment operation, the first motor 4 drives the conveyor shaft 14 and the spiral blade 23 to rotate continuously. The edge of the spiral blade 23 continuously presses down on the ball head 58, causing the entire set of connecting rods and support rods 51 to swing downwards synchronously. The torsion spring 52 is subjected to force and to twists to store elastic potential energy. When the spiral blade 23 rotates past the ball head 58, the pressure of the blade on the ball head disappears instantly. The torsion spring 52 quickly releases its tension and pulls all components upwards. The actuating frame 57 synchronously and at high frequency reciprocates to impact the material inside the feed hopper 5, continuously breaking up the arched support structure formed by the material. No additional independent drive motor is required throughout the process. Automatic arch breaking is achieved by relying on the main force of the spiral conveyor.

[0030] Example 4 In the spiral conveying mechanism, the first motor 4 is a variable frequency servo motor, and the reducer 3 is a planetary gear reducer with a reduction ratio range of 1:20 to 1:60; the conveying shaft 14 is fully welded and fixed to the spiral blade 23, and the single-sided gap between the outer edge of the spiral blade 23 and the inner wall of the spiral conveying shell 2 is controlled at 1.5mm to 3mm; the spiral conveying shell 2, the feeding hopper 5, the metering hopper 6, and the weighing hopper 9 are made of 304 stainless steel or 316L medical stainless steel, and the inner wall of the hopper is mirror polished.

[0031] In this embodiment, the spiral blades 23 are fixed to the outer periphery of the conveying shaft 14 by a continuous full welding process. A 1.5mm to 3mm single-sided gap is reserved between the outer edge of the spiral blades 23 and the inner wall of the spiral conveying housing 2, which can prevent small particles from getting stuck and ensure material conveying efficiency.

[0032] Example 5 The output end of the second motor 11 of the re-weighing premixing mechanism is sealed and extends into the re-weighing hopper 9 to form a rotating shaft 91. The rotating shaft 91 is uniformly and detachably mounted with four inclined material-pushing plates 92 at 40° to 50°. Rectangular grate holes 93 are equally spaced on the material-pushing plates 92, and the width of the grate holes 93 is greater than 1.2 times the maximum particle diameter of the material. The side wall of the re-weighing hopper 9 is connected to a negative pressure pipe 10, which is connected to an air compressor. Both the negative pressure conveying pipe 8 and the inner wall of the re-weighing hopper 9 are coated with an antistatic polyurethane coating with a thickness of 0.2 to 0.5 mm.

[0033] In this embodiment, the re-weighing premixing mechanism is mounted on the second weighing device 12. The second weighing device 12 and the first weighing device 7 use the same specification cantilever beam high-precision sensor. The signals of the two are synchronously connected to the same PLC control system. The PLC integrates two-level weighing value comparison, dynamic automatic material replenishment, weight deviation audible and visual alarm, production data storage and export multiple control logics, which can completely record the material ratio data of each batch. A second motor 11 is horizontally fixed on the outside of the weighing hopper 9. The motor output shaft has a sealed structure that extends into the inner cavity of the weighing hopper 9 to form a rotating shaft 91. Four inclined material-pushing plates 92, with a tilt of 40° to 50°, are detachably installed on the rotating shaft 91 along the circumference. The material-pushing plates 92 are fixed by bolts and can be individually removed and replaced after wear. Each material-pushing plate 92 has rectangular through-grate holes 93 at equal intervals on its surface. The width of a single grate hole 93 is greater than 1.2 times the maximum particle diameter of the material. The material falling under negative pressure impacts the rotating material-pushing plates 92, causing agglomeration and dispersal. Some of the material slides down the plate surface, while some passes through the grate holes 93 and is diverted. Multiple raw materials are pre-mixed during the falling process. The PLC automatically compares the primary weighing value with the secondary weighing value. If the weight difference exceeds the preset error threshold, the system automatically starts the replenishment process until the weight difference between the two weighing stages reaches the standard. After the verification is qualified, the solenoid valve at the bottom of the weighing hopper 9 opens, and the material is directly discharged into the reaction vessel 13 below to complete the subsequent synthesis processing.

[0034] Example 6 Both the first weighing device 7 and the second weighing device 12 are high-precision weighing sensors with multi-point cantilever beams, and their signals are synchronously connected to the PLC control system. The PLC has built-in two-level weighing data comparison, dynamic automatic material replenishment, audible and visual alarm for weight deviation, and production data storage and export multiple control logics, which can record the material ratio data of each batch in real time.

[0035] In this embodiment, the first weighing device 7 collects the weight data of the material inside the metering hopper 6 in real time and transmits it to the PLC control system. The system pre-stores the standard weight of various raw materials. The screw conveyor continuously feeds the material into the metering hopper 6. When the material weight reaches 95% of the target weight, the PLC controls the first motor 4 to reduce the speed and feed the material at a low speed. When it is close to the standard weight, the discharge end adjustment mechanism is used to reduce the discharge cross section to accurately complete the quantitative feeding. After the set weight is reached, the first motor 4 stops and the solenoid valve at the bottom of the metering hopper 6 opens to discharge the material.

[0036] Example 7 The spring 17 of the discharge flow rate adjustment mechanism is a replaceable cylindrical compression spring with a wire diameter of 1.5mm to 5mm to adapt to materials of different densities; a wear-resistant rubber buffer pad is attached to one side of the adjustment plate 19 that is in contact with the discharge end; the two ends of the spring 17 press against the baffle plate 18 and the fixing ear 15 respectively, and the adjustment plate 19 is automatically opened by the material thrust. When there is no material, the spring 17 rebounds and narrows the discharge cross section to achieve adaptive flow rate adjustment.

[0037] In this embodiment, when there is no material conveying, the spring 17 pushes the baffle 18 to drive the adjusting plate 19 to fit tightly against the discharge end face, reducing the discharge flow cross section; when the screw conveyor pushes the material, the horizontal thrust generated by the material accumulation pushes the adjusting plate 19 outward, and simultaneously compresses the spring 17 to automatically expand the discharge cross section. When the material supply decreases, the spring 17 rebounds and narrows the flow area. The discharge flow rate is adaptively adjusted by relying on the pure mechanical structure, buffering the impact of the falling material and avoiding large fluctuations in the weighing data.

[0038] Example 8 The emergency unloading mechanism has an arc-shaped support plate 20 with a high-chromium wear-resistant liner bonded to the inner arc surface and annular sealing strips on both sides. A connecting plate 22 is welded to the lower end of the emergency support plate 20. The connecting plate 22 is rigidly connected to the horizontal telescopic rod 21. The cylinder drives the telescopic rod 21 to move and control the opening and closing of the unloading port. During normal production, the sealing strip is attached to the bottom unloading port of the spiral conveyor shell 2.

[0039] In this embodiment, an arc-shaped discharge port is opened at the bottom of the discharge end of the screw conveyor shell 2. The discharge port is equipped with an arc-shaped emergency support plate 20. A high-chromium wear-resistant liner is bonded to the inner arc surface of the emergency support plate 20. Annular sealing strips are installed on both sides of the support plate. Under normal production conditions, the sealing strips are tightly fitted to the discharge port, completely sealing the discharge port and preventing material leakage and dust leakage. A horizontal connecting plate 22 is welded to the lower end of the emergency support plate 20. A horizontal telescopic rod 21 is rigidly connected to the outer side of the connecting plate 22. A discharge cylinder is fixed to the side wall of the bracket 1, and the output end of the cylinder is connected to the end of the telescopic rod 21. When material blockage, material caking, or equipment shutdown for maintenance occurs inside the screw, the control system outputs a signal to control the cylinder to retract, pulling the telescopic rod 21 and connecting plate 22 to move the emergency support plate 20 horizontally outward, fully opening the bottom arc-shaped discharge port. The material trapped inside the screw shell falls naturally under gravity, and a collection bucket can be placed below the discharge port to quickly recover the material. After the cleaning operation is completed, the cylinder extends and pushes the emergency support plate 20 to reset and seal the discharge port. There is no need to disassemble the screw conveyor shell 2, which greatly shortens the downtime for fault cleaning.

[0040] Example 9 The whole machine is equipped with a complete set of intrinsically safe explosion-proof electrical assemblies. The first motor 4, the second motor 11, the solenoid valve, the weighing sensor, and the PLC controller are all explosion-proof components. The bracket 1, the screw conveyor shell 2, each hopper, and the negative pressure pipe 10 are connected by anti-static grounding wires. The grounding resistance of the whole machine is controlled within 4Ω, which is suitable for continuous batching production of flammable and explosive powders in chemical and pharmaceutical industries.

[0041] In this embodiment, the entire equipment is equipped with a complete set of intrinsically safe explosion-proof electrical assemblies. The first motor 4, the second motor 11, the pneumatic solenoid valve, the weighing sensor, and the PLC controller are all made of explosion-proof components. Anti-static grounding wires are installed between the support frame 1, the screw conveyor housing 2, each silo, and the negative pressure conveying pipeline 8 to connect them. The grounding resistance of the entire machine is controlled within 4Ω, which can adapt to the continuous batching production conditions of flammable and explosive powders in chemical and pharmaceutical industries. The entire equipment relies on only two drive motors to complete all conveying, arch breaking, and premixing processes. The mechanical linkage structure simplifies the electrical control circuit, reduces equipment manufacturing costs and subsequent operation and maintenance difficulties, and realizes integrated continuous batching operations with self-driven arch breaking, two-stage weighing verification, material premixing, adaptive flow adjustment, and emergency unloading in case of failure.

[0042] The working method (or working principle) of this invention: When this technology is in operation, after the raw material is put into the feed hopper 5, the first motor 4 drives the spiral blade 23 to rotate. The blade continuously squeezes and pushes the ball head 58, which drives the entire arch-breaking mechanism to press down and causes the torsion spring 52 to store energy. After the blade rotates past the ball head, the torsion spring 52 rebounds and drives the pusher frame 57 to vibrate at high frequency to break the material arching and caking.

[0043] The material is conveyed by a screw conveyor to the weighing hopper 6 for primary weighing. The discharge end spring 17 and the regulating plate 19 work together to adaptively buffer and regulate the discharge flow rate. After the weighing meets the standard, the material is conveyed to the re-weighing hopper 9 through the negative pressure pipe 10 in a closed system. The air compressor forms a negative pressure to complete the dust-free transfer. Inside the re-weighing hopper 9, the second motor 11 drives the inclined material-pulling plate 92 with grate holes 93 to rotate, breaking up the agglomerated material and achieving preliminary mixing of multiple raw materials. At the same time, the second weighing device 12 completes the secondary weighing verification. The PLC compares the weight data of the two stages to realize automatic material replenishment and over-tolerance alarm. The qualified material is discharged into the reaction vessel 13 to participate in the reaction.

[0044] When the inside of the spiral is blocked, the cylinder on the support 1 pulls the telescopic rod 21 to move the emergency support plate 20 to open the bottom discharge port and quickly discharge the stuck material. The whole machine relies on mechanical linkage to eliminate the need for an independent arch-breaking drive, taking into account the batching accuracy, the smoothness of material discharge and the ability to quickly clean up faults.

[0045] In this invention, unless otherwise explicitly specified and limited, for example, it can be a fixed connection, a detachable connection, or an integral part; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two elements or an interaction between two elements. Unless otherwise explicitly limited, those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0046] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A hopper unloading device with a weighing mechanism, characterized in that: Includes a support (1), on which are provided a screw conveyor mechanism, a feed hopper (5), a self-driven arch-breaking device, a primary metering mechanism, a negative pressure conveying pipeline (8), a re-weighing premixing mechanism, a discharge flow rate regulating mechanism, an emergency unloading mechanism and a reaction vessel (13); The spiral conveying mechanism includes a spiral conveying housing (2), a first motor (4), a reducer (3), a conveying shaft (14), and spiral blades (23). The feed hopper (5) is connected to the top of the spiral conveying housing (2). The self-driven arch-breaking device is located inside the feed hopper (5) and includes a support rod (51), a torsion spring (52), a connecting rod assembly, and a push ball (58). The push ball (58) is engaged in the spiral groove of the spiral blade (23). The primary metering mechanism includes a metering hopper (6) and a first weighing device (7), with the bottom of the metering hopper (6) connected to a negative pressure conveying pipe (8); the secondary weighing premixing mechanism includes a secondary weighing hopper (9), a second weighing device (12), a second motor (11), and a material feeding plate (92) with grate holes (93), with the negative pressure conveying pipe (8) connected to the secondary weighing hopper (9), and the bottom of the secondary weighing hopper (9) connected to the reaction vessel (13); The discharge flow rate adjustment mechanism includes a fixed lug (15), a guide rod (16), a spring (17), a baffle (18), and an adjustment plate (19); the emergency unloading mechanism includes an emergency support plate (20), a telescopic rod (21), a connecting plate (22), and a drive cylinder. The self-driven arch-breaking device is provided with two symmetrical support rods (51), each support rod (51) is independently equipped with a set of torsion springs (52), the two ends of the torsion springs (52) are respectively pressed against the support rod (51) and the inner wall of the feed hopper (5); the lower end of the support rods (51) is connected to a connecting sleeve (53), the lower end of the connecting sleeve (53) is threaded with an adjusting cylinder (54) with a locking bolt, the first connecting rod (55) is slidably installed in the adjusting cylinder (54), the bottom end of the first connecting rod (55) is detachably installed with a toggle ball head (58); the upper end of the connecting sleeve (53) is connected to a second connecting rod (56), the top end of the second connecting rod (56) is provided with an L-shaped toggle frame (57) that extends into the material area of ​​the feed hopper (5); the toggle ball head (58) is a polyurethane matrix with a ceramic wear-resistant coating structure, and the torsion spring (52) is made of high temperature chromium vanadium spring steel and sprayed with an anti-corrosion epoxy layer; The spring (17) of the discharge flow rate adjustment mechanism is a replaceable cylindrical compression spring (17) with a wire diameter of 1.5mm to 5mm to adapt to materials of different densities; the adjustment plate (19) is attached to the side of the discharge end with a wear-resistant rubber buffer pad; the two ends of the spring (17) press against the baffle (18) and the fixing ear (15) respectively, and the adjustment plate (19) is automatically opened by the material thrust. When there is no material, the spring (17) rebounds and narrows the discharge cross section to achieve adaptive flow rate adjustment.

2. A silo unloading device with a weighing mechanism according to claim 1, characterized in that: In the spiral conveying mechanism, the first motor (4) is a variable frequency servo motor, the reducer (3) is a planetary gear reducer, and the reduction ratio range is 1:20~1:60; the conveying shaft (14) and the spiral blade (23) are fully welded and fixed, and the single-sided gap between the outer edge of the spiral blade (23) and the inner wall of the spiral conveying shell (2) is controlled at 1.5mm~3mm; the spiral conveying shell (2), the feeding hopper (5), the metering hopper (6), and the weighing hopper (9) are made of 304 stainless steel or 316L medical stainless steel, and the inner wall of the hopper is mirror polished.

3. A silo unloading device with a weighing mechanism according to claim 1, characterized in that: The output end of the second motor (11) of the re-weighing premixing mechanism is sealed and extends into the re-weighing hopper (9) to form a rotating shaft (91). The rotating shaft (91) is uniformly and detachably installed with four inclined material-pulling plates (92) at 40° to 50° along the circumference. Rectangular grate holes (93) are opened at equal intervals on the material-pulling plates (92). The width of the grate holes (93) is greater than 1.2 times the maximum particle diameter of the material. The side wall of the re-weighing hopper (9) is connected to a negative pressure pipe (10). The negative pressure pipe (10) is connected to an air compressor. The negative pressure conveying pipe (8) and the inner wall of the re-weighing hopper (9) are both sprayed with an antistatic polyurethane coating with a thickness of 0.2 to 0.5 mm.

4. A silo unloading device with a weighing mechanism according to claim 1, characterized in that: The first weighing device (7) and the second weighing device (12) are both high-precision weighing sensors with multi-point cantilever beams. Their signals are synchronously connected to the PLC control system. The PLC has built-in two-level weighing data comparison, dynamic automatic material replenishment, audible and visual alarm for weight deviation, and production data storage and export multiple control logics, which can record the material ratio data of each batch in real time.

5. A silo unloading device with a weighing mechanism according to claim 1, characterized in that: The emergency unloading mechanism has an arc-shaped pallet (20) with a high-chromium wear-resistant liner bonded to the inner arc surface and annular sealing strips on both sides. A connecting plate (22) is welded to the lower end of the emergency pallet (20), and the connecting plate (22) is rigidly connected to the horizontal telescopic rod (21). The cylinder drives the telescopic rod (21) to move horizontally to control the opening and closing of the unloading port. During normal production, the sealing strip is attached to the bottom unloading port of the spiral conveyor shell (2).

6. A silo unloading device with a weighing mechanism according to claim 1, characterized in that: Two-position five-way pneumatic unloading solenoid valves are installed between the metering hopper (6) and the negative pressure conveying pipeline (8), and between the weighing hopper (9) and the reactor (13); all solenoid valve flange mating surfaces are fitted with fluororubber high-temperature resistant sealing gaskets, and all silos and pipeline flange joints of the entire equipment are equipped with anti-static cross-connection sealing structures.

7. A silo unloading device with a weighing mechanism according to any one of claims 1-6, characterized in that: The first motor (4), the second motor (11), the solenoid valve, the weighing sensor, and the PLC controller are all explosion-proof components; the bracket (1), the screw conveyor shell (2), each hopper, and the negative pressure pipe (10) are connected by anti-static grounding wires, and the grounding resistance of the whole machine is controlled within 4Ω, which is suitable for continuous batching production of flammable and explosive powders in chemical and pharmaceutical industries.

Images