A mobile box type asphalt milling material fine stripping device and working method

Abstract

The application discloses a mobile box type asphalt milling material fine stripping device and a working method, which comprises a spiral stripping device, a stirring drum device, a fixing device and a transmission device.The main shaft of the spiral stripping device is high-speed rotating to make the aggregate impact the inner wall of the stirring drum, forming an impact-grinding cooperative stripping mechanism.The inner wall of the cylinder of the stirring drum device is provided with a spiral rib plate with a rotation direction opposite to that of the spiral blade of the main shaft, so that the material is subjected to the double actions of the axial propulsion force and the cylinder back thrust force.The fixing device comprises a torsion-resistant box type structure composed of a double-sided box connected through three thin shafts, a bottom I-steel support frame and a top square steel support beam.The transmission device drives the main shaft and the stirring drum to rotate in the same direction.The outer edge of the spiral blade is provided with a detachable cutter, and the main shaft is provided with an anti-accumulation stirring device.The inner wall of the stirring drum is welded with an array of wear-resistant nails, and the feeding port and the discharging port adopt a non-contact structure.The rotating speed of the main shaft is greater than that of the stirring drum.The application improves the effective processing time and portability of the device.

Description

Technical Field

[0001] This invention belongs to the field of mechanical design technology, and in particular relates to a mobile box-type asphalt milling material fine stripping device and its working method. Background Technology

[0002] Reclaimed asphalt pavement (RAP) is a major waste generated during road maintenance and reconstruction, but it is also a valuable renewable resource containing asphalt and high-quality aggregates. Achieving efficient recycling of RAP is crucial for conserving natural resources, reducing road construction costs, minimizing solid waste emissions, and promoting green transportation development. A key aspect of achieving high-value utilization lies in effectively stripping aged asphalt from the aggregate surface and restoring the asphalt's original properties as much as possible.

[0003] Currently, there are three main methods in the industry for processing RAP materials.

[0004] Thermal desorption involves heating the asphalt at high temperatures (usually above 150°C) to soften and allow it to flow or crack, thus separating it from the aggregate. Although the equipment for this method is relatively mature, it has significant drawbacks, including high energy consumption, severe asphalt aging, the generation of harmful gases during the heating process, and asphalt coking and sticking within the equipment.

[0005] Solvent extraction uses organic solvents (such as trichloroethylene) to dissolve asphalt, which theoretically has a good separation effect. However, it faces serious challenges such as high solvent toxicity, high cost, difficulty in recycling, residual pollution and high environmental risks, resulting in poor economic efficiency and safety.

[0006] Mechanical physical stripping technology, operating at room temperature or lower temperatures, avoids secondary aging of asphalt at high temperatures and avoids solvent pollution problems, demonstrating good energy-saving and environmental protection potential, and has become the focus of current research and application. This method mainly achieves separation by breaking the adhesion between asphalt and aggregate through strong mechanical actions such as stirring, impact, grinding, and kneading. However, existing mechanical physical stripping devices still have many key problems that need to be solved in practical applications: (1) Low stripping efficiency and serious residue. The mechanical force of existing devices is often single, concentrated, or too rigid, making it difficult to achieve uniform and sufficient stripping on the aggregate surface; (2) Serious aggregate damage. Existing devices often apply strong mechanical actions such as high-intensity impact, extrusion, or shearing, which destroys the original gradation of the recycled aggregate; (3) Rapid wear and cumbersome replacement of key parts of the equipment. The core working components of the device (such as stirring blades / rotors, wear-resistant liners, inner walls of the cavity, etc.) wear out very quickly. The replacement of key stripped parts often requires the disassembly of the entire device, resulting in high component replacement and maintenance costs; (4) Most existing devices are discrete processing methods, with a low proportion of effective processing time, low equipment utilization, and limited processing capacity per unit time (tons / hour); (5) Existing devices generally have the problems of large size and huge overall weight, which cannot meet the needs of distributed, small-batch RAP processing, and are difficult to transport and install. Summary of the Invention

[0007] To achieve the above objectives, the present invention provides a mobile box-type asphalt milling material fine stripping device, comprising: The spiral stripping device uses a high-speed rotating main shaft to cause the aggregate to impact the inner wall of the mixing drum, forming an impact-grinding synergistic stripping mechanism. The mixing drum device has spiral ribs on its inner wall that rotate in the opposite direction to the spiral blades of the main shaft, so that the material is subjected to both axial propulsion force and drum back thrust. The fixing device includes a torsion-resistant box-shaped structure consisting of a double-sided box body connected by three thin shafts, a bottom I-beam support frame, and a top square steel support beam. The transmission device drives the main shaft and the stirring drum to rotate in the same direction. The outer edge of the spiral blades is equipped with a detachable cutter, and the main shaft is equipped with a stirring device to prevent accumulation. The inner wall of the mixing drum is welded with an array of wear-resistant nails, and the inlet and outlet adopt a non-contact structure. The spindle speed is greater than the stirring drum speed.

[0008] Optionally, the spiral stripping device includes: The main shaft is welded with four sets of right-hand spiral blades and two sets of stirring devices; Coated cutting tools are mounted on the outer tool holder of the spiral blades, with round tooth cutting tools configured in the inlet / outlet sections and pointed tooth cutting tools configured in the middle section; The tool body is made of high-speed steel, and the cutting zone has a cemented carbide coating structure.

[0009] Optionally, the stirring drum assembly includes: The horizontal cylindrical body is ≤1.6 meters high and has four left-handed spiral ribs on the inner wall; Hard alloy wear-resistant nails are arranged between the spiral ribs, and a large toothed ring and double-sided outer raceways are welded to the outer periphery of the cylinder. The left and right ends are equipped with openable bin doors, and the discharge window is located at the right end of the cylinder.

[0010] Optional, the fixing device includes: Three thin shafts are evenly distributed around the circumference and installed on the left and right fixed boxes. The thin shaft is fitted with a concave roller, which forms a rolling fit with the outer raceway of the cylinder. The bottom double I-beam steel frame is welded to three auxiliary square steel beams, and the top two square steel support beams are pre-tightened to connect the box body with bolts.

[0011] Optionally, the transmission device includes: The motor drives the main shaft to rotate via a pulley; The clutch-linked gear set, with the shaft gear meshing with the large gear ring, drives the cylinder to rotate.

[0012] Optionally, the tool assembly configuration process includes: Countersunk holes are made at intervals in the tool holder, and high-strength bolts are used to fix the round tooth tool and the pointed tooth tool; The pointed tooth cutter is arranged in the two sets of spiral blades in the middle, and the round tooth cutter is arranged in the two sets of spiral blades at the ends.

[0013] Optionally, the material stripping process includes: The aggregate is subjected to centrifugal impact from the main shaft against the wear-resistant nails and cylinder wall, achieving stone-on-iron separation; The collision of aggregates produces stone-on-stone grinding; The sharp-toothed cutting tool scrapes the asphalt layer off the surface of the aggregate.

[0014] Optional, continuous processing includes: After screening, the coarse aggregate is conveyed into the cylinder through the feed inlet of the left fixed box via a conveyor. After processing, the material is centrifugally ejected from the right end of the cylinder and then discharged through the inclined flow inside the right fixed box. The top lifting lugs on both sides of the container are suitable for standard container transportation.

[0015] On the other hand, to achieve the above objectives, the present invention also provides a method for operating a mobile box-type asphalt milling material fine stripping device, comprising: The screened coarse aggregate is conveyed to the feed inlet of the left fixed box by a conveyor, and then enters the mixing drum after passing through the internal flow channel of the left fixed box. The coarse aggregate moves towards the discharge port within the processing chamber under the conveying action of the screw shaft; During the forward movement, the coarse aggregate undergoes impact crushing, grinding and cutting. Impact crushing is achieved by the parabolic motion of the aggregate colliding with the wear-resistant nails or the inner surface of the cavity. Grinding is achieved by the mutual squeezing and friction between the aggregates. Cutting is achieved by the scraping of the aggregate surface by the cutter on the spiral blade. The processed aggregates and asphalt are discharged from the outlet through the conveying of the main shaft and the centrifugal force of the processing chamber; The discharged aggregate and asphalt are separated by a screening device to obtain coarse aggregate and asphalt.

[0016] Technical advantages of this invention: This invention discloses a mobile box-type asphalt milling material fine stripping device and its working method. The main shaft can both transport the aggregate and remove waste asphalt from the surface of the aggregate. The main shaft also has a mixing device to prevent aggregate accumulation and the formation of dead zones. Furthermore, spiral ribs inside the drum allow for aggregate backflow, ensuring thorough grinding between aggregates and improving the stripping effect to a certain extent. The horizontal drum design, with its specially designed fixing device, lowers the center of gravity of the device, ensuring stability during operation. The stripping blades are interchangeable and can be replaced when severely worn. Wear-resistant nails are welded inside the mixing drum to prevent direct wear on the inner surface of the mixing drum, reducing maintenance costs and extending the service life of the mixing drum. The device adopts a continuous processing method, improving effective processing time and equipment utilization. The device is flexible, portable, and compact. By lifting the left and right fixed boxes with lifting lugs, the processing device can be loaded into a standard container for transportation, solving the problems of difficulty in processing, transporting, and installing distributed, small-batch coarse aggregates. Attached Figure Description

[0017] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a schematic diagram of the continuous asphalt milling material stripping device according to an embodiment of the present invention; Figure 2 This is a top view of the continuous asphalt milling material stripping device according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of the stirring drum device according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of the left fixed box in an embodiment of the present invention; Figure 5 This is a schematic diagram of the right fixed box in an embodiment of the present invention; Figure 6This is a schematic diagram of the main shaft structure according to an embodiment of the present invention; Figure 7 This is a schematic diagram of the transmission system with the right fixed box removed, according to an embodiment of the present invention. Among them, 1-Conveyor, 2-Left fixed box, 3-Lifting lug, 4-Square steel support beam, 5-Roller, 6-Shaft gear, 7-Fine shaft, 8-Right fixed box, 9-Motor, 10-Agitating drum, 11-Bottom support frame, 12-Auxiliary square steel, 13-Main feed inlet, 14-Large gear ring, 15-Main discharge outlet, 16-Agitating drum feed inlet, 17-Spiral rib, 18-Outer raceway, 19-Left compartment door, 20-Wear-resistant nail, 21-Right compartment door, 22-Agitating drum discharge window, 23-Agitating drum main shaft support end, 24-Left fixed box feed inlet, 25-Left fixed box fine shaft support 26-Left fixed box main shaft support end, 27-Right fixed box thin shaft support end, 28-Right fixed box main shaft support end, 29-Agitator drum extension end, 30-Motor shaft support end, 31-Main shaft bearing end, 32-Main shaft, 33-Circular tooth cutter, 34-Helical blade, 35-Agitator, 36-Cutter holder, 37-Sharp tooth cutter, 38-Coupling, 39-Motor shaft, 40-Belt drive system ①, 41-Clutch, 42-Pinary gear, 43-Large gear, 44-Large gear shaft, 45-Belt drive system ②, 46-Pinary gear shaft, 47-Self-aligning roller bearing support device. Detailed Implementation

[0018] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0019] like Figures 1-7 As shown in the figure, this embodiment provides a mobile box-type asphalt milling material fine stripping device, which includes four main parts: a spiral stripping device, a mixing drum device, a fixing device, and a transmission system.

[0020] As a further technical solution, the spiral stripping device includes a central main shaft, spiral blades, a stirring device, and cutting tools. Under high-speed rotation, the main shaft uses centrifugal force to radially impact coarse aggregate particles onto the inner surface of the stirring drum and wear-resistant spikes, thus creating an impact crushing effect. In this dynamic process, the aggregate particles first gain kinetic energy under centrifugal force, and then undergo multiple mechanical actions: high-speed collision with the drum surface leading to impact crushing, sliding friction at the particle-drum interface generating shearing action, and mutual grinding effect between particle groups. By precisely controlling the main shaft angular velocity ω, the impact intensity can be graded and controlled, which is the physical basis for the device's efficient crushing. The particle group forms an impact-grinding synergistic stripping mechanism within the crushing chamber, thereby significantly improving the stripping efficiency.

[0021] As a further technical solution, the spiral stripping device consists of a main shaft and four sets of spiral blades arranged in a spatial spiral pattern. An optimized spacing is set between adjacent blades to ensure that the aggregate particles can achieve sufficient squeezing and grinding between the working surface of the blades and between the particles.

[0022] As a further technical solution, a cutting tool is mounted on the outer surface of the helical blade. When the spindle drives the helical blade to rotate, it can cut the surface of the asphalt aggregate. The tool is a detachable tool that can be directly mounted on the tool holder on the outer side of the blade. In addition, the helical blade can also play a role in transporting the asphalt aggregate.

[0023] As a further technical solution, a stirring device is welded onto the main shaft to prevent the accumulation of asphalt aggregate and to enhance the collision effect between asphalt aggregate.

[0024] As a further technical solution, the aforementioned mixing drum device includes a drum body, spiral ribs, and wear-resistant nails. The horizontal drum layout adopted in this invention arranges the mixing drum horizontally, with the material moving axially from the left inlet to the right outlet. While maintaining the effective working length of the main shaft, the overall height of the device is compressed to within 1.6 meters.

[0025] As a further technical solution, the mixing drum has spiral ribs. To enhance the grinding effect of the asphalt aggregates pressing against each other, the material propulsion direction generated by the rotation of the spiral ribs is opposite to the conveying direction of the main shaft spiral blades. This allows the material to be subjected to the dual action of the main shaft propulsion force and the drum body back thrust in the mixing drum, which can ensure sufficient grinding between the asphalt aggregates and effective cutting between the asphalt and the cutting tools, thereby achieving efficient removal of waste asphalt layers.

[0026] As a further technical solution, there are regularly arranged wear-resistant nails between the spiral ribs of the mixing drum. As the primary wear-resistant barrier, these nails can prevent direct wear of the drum body, enhance the friction effect between the aggregate and the wear-resistant nails, and improve the mechanical peeling efficiency of the old asphalt bonding layer.

[0027] As a further technical solution, the fixing device includes left and right fixed housings, a bottom support frame, thin shafts, square steel support beams, and lifting lugs and self-aligning roller bearing support devices. This device uses double left and right fixed housings as the core fixing system, with three thin shafts evenly distributed around the circumference and installed on the positioning housings to form a stable support system. The three thin shafts support the mixing drum body, and the left and right fixed housings support the main shaft. To enhance the rigidity and stability of the overall structure, two I-beam hot-rolled channel steels are installed at the bottom of the two housings as bottom support frames, pre-tightened to the left and right housings using high-strength bolts. In addition, several spaced auxiliary square steels are installed between the two bottom main channel steels, significantly improving the torsional stiffness of the device in the width direction. Two square steel support beams are also installed at the top of the housings, forming a box-type load-bearing structure together with the bottom frame.

[0028] As a further technical solution, the device adopts a horizontal structure, and its feeding system and the rotating mixing drum employ a non-contact structure. The feed inlet is located at the left fixed box, ensuring continuous feeding without interference while the drum rotates. The discharge outlet is located at the right positioning box, utilizing the centrifugal force generated by the rotation of the drum to throw out the processed aggregate and discharge it through the outlet.

[0029] As a further technical solution, the top of the left and right fixed boxes has four symmetrical lifting lugs, which can be used to lift the device after it is transported to the site. In addition, the overall size of the device is smaller than that of a standard shipping container, realizing the portable transportation of the device.

[0030] As a further technical solution, the self-aligning roller bearing support device plays a major supporting role for the mixing drum.

[0031] As a further technical solution, the transmission device includes a conveyor, a high-power motor, gear transmission, and belt transmission. The stripping device requires a main shaft and a mixing drum for driving. The spiral main shaft is arranged along the central axis of the mixing drum and employs a special structural design with spiral blades added to the main shaft. Under the action of the drive system, it generates axial propulsion and radial extrusion forces on the material, causing the material to undergo interfacial separation of asphalt and aggregate through extrusion and grinding between materials and between the material and the device, achieving the desired stripping effect. The mixing drum, as a container, supports the entire processing process and has four rows of spiral ribs inside. While maintaining its continuous rotation, it uses the spiral ribs on its own wall to push the aggregate to achieve material circulation, ensuring thorough stripping of the material.

[0032] As a further technical solution, the high-power motor transmits power to the motor shaft, and pulleys are installed on the motor shaft and the main shaft. The torque of the motor is transmitted to the rotating shaft through the belt drive.

[0033] As a further technical solution, the outer cylinder of the stirring drum has a gear ring, which enables the stirring drum to rotate through gear engagement. Rollers are arranged on three thin shafts supporting the outer cylinder of the stirring drum. The rollers form rolling contact with the hardened raceway on the outer wall of the outer cylinder through precision-machined grooves, ensuring the smooth operation of the stirring drum device.

[0034] As a further technical solution, the rotation direction of the main shaft and the outer cylinder causes the material to move in opposite directions. The main shaft pushes the material axially toward the discharge port, and the cylinder pushes the material toward the inlet to achieve material return.

[0035] This embodiment also includes a method for operating the mobile box-type asphalt milling material fine stripping device, comprising the following steps: After the primary crushed asphalt milling material is screened, the smaller fine aggregate is removed, and the coarse aggregate is transported to the feed inlet by a conveyor and flows into the feed port of the mixing drum through the internal channels of the left fixed box.

[0036] Under the influence of gravity, the coarse aggregate slides down the inclined surface of the cavity into the cavity. After gaining a certain initial velocity, under the conveying action of the screw shaft, the coarse aggregate will move axially towards the discharge port.

[0037] In the section away from the spiral blades, the rotation of the mixing drum will cause the coarse aggregate to rotate to a certain height and then undergo parabolic motion. At this point, the coarse aggregate falls under the influence of gravity and collides with the aggregate below. Friction between the aggregates generates shear force, which promotes the removal of aged asphalt on the surface, achieving stone-on-stone collision. In addition, the coarse aggregate will also collide with wear-resistant nails or the inner surface of the cavity during its fall, causing the asphalt on the surface of the coarse aggregate to fall off, achieving stone-on-iron collision.

[0038] Near the helical blade segment, the cutting blades mounted on the helical blades scrape the surface of the coarse aggregate, removing aged asphalt. Simultaneously, the blades apply an upward force to the aggregate, causing it to grind and compress against each other, propelling it towards the discharge port. The mixing device between the two helical blades applies an impact force to the aggregate accumulated there, enhancing the friction between the asphalt aggregates.

[0039] The processed coarse aggregate and waste asphalt are transported to the discharge window of the mixing drum via the main shaft. The aggregate and asphalt are discharged through the screw conveying action of the main shaft and the centrifugal force generated by the mixing drum, and then flow out through the channels in the right fixed box. After exiting the discharge end, the aggregate is screened by a screening device to obtain coarse aggregate and asphalt separately.

[0040] Example 1: This embodiment provides a mobile box-type asphalt milling material fine stripping device.

[0041] In a typical embodiment of the present invention, such as Figures 1-7 As shown, the device mainly includes a spiral peeling device, a stirring drum device, a fixing device, and a transmission system.

[0042] The spiral peeling device provided in this embodiment, such as Figure 6 As shown, the device includes a spindle bearing end 31, a spindle 32, a circular gear cutter 33, a helical blade 34, a stirring device 35, a tool holder 36, and a pointed gear cutter 37. The spindle bearing end 32 is used to install the bearing; since the spindle must withstand a large radial force during rotation, a double-row tapered roller bearing can be used here. The helical blade 34 and the stirring device 35 are welded onto the spindle 32. The outer surface of the helical blade 34 has a rectangular groove structure to support the tool holder 36. This invention adopts a modular tool design strategy: countersunk holes are drilled at fixed intervals on the tool holder 36 for mounting the circular gear cutter and the pointed gear cutter using high-strength fastening bolts. The tool adopts a coated tool design scheme; the tool base is made of high-speed steel, the key cutting areas are made of cemented carbide, and a wear-resistant coating is applied to the surface of the cemented carbide, significantly improving the wear resistance of the tool. Four sets of helical blades and two sets of stirring devices are welded onto the spindle 32. In the optimized design of the cutting tool system, the tool holder can be adapted to cutting tool components with different geometric features, such as multiple circular teeth, multiple flat teeth, and multiple pointed teeth, to achieve differentiated stripping treatment of asphalt mixtures. Based on the state of the material inside the mixing drum, the stripping effect can be optimized through the dynamic configuration of the cutting tool combination. To avoid excessive material accumulation at the inlet and outlet, and to prevent significant cutting resistance between the aggregate and the cutting tools, circular tooth cutting tools 33 are used on the two end spiral blades; the cutting tools on the two middle spiral blades mainly bear the cutting action, so pointed tooth cutting tools 37 are used. Two sets of mixing devices are installed between the two spiral blades, firstly to avoid aggregate accumulation, and secondly to enhance the mutual collision between the aggregates.

[0043] like Figure 1 , Figure 3As shown, the mixing drum device provided in this embodiment includes a mixing drum 10, a large gear ring 14, a mixing drum inlet 16, a spiral rib 17, an outer raceway 18, a left chamber door 19, wear-resistant nails 20, a right chamber door 21, a mixing drum outlet window 22, and a mixing drum main shaft support end 23. Because this device adopts a horizontal structure, its feeding system and the mixing drum 10 use a non-contact structure. Its left end is designed in a conical shape, and the main inlet 13 extends into the mixing drum 10, ensuring continuous feeding without interference during drum rotation. This, along with the falling of coarse aggregate, imparts a certain initial velocity to the aggregate. As the coarse aggregate enters the mixing drum 10, it is subjected to the axial thrust of the main shaft and the scraping force of the spiral blades, causing the aged asphalt on its surface to peel off and propel it towards the outlet. The shaft gear 6 and the large gear ring 14 are matched according to a certain tooth ratio. The large gear ring 14 is located at the center of the cylindrical cavity, and three shaft gears 6 are evenly distributed around its circumference. The rotation of the shaft gears 6 drives the large gear ring 14 to achieve a reduced speed rotation. Two outer raceways 18 are symmetrically distributed on both sides of the large gear ring 14. The outer raceways 18 are welded to the outer surface of the mixing drum and are raised, which can cooperate with the rollers 5 to maintain the stability of operation. The left compartment door 19 and the right compartment door 21 are distributed on the left and right sides of the mixing drum 10. The left and right compartment doors are installed on the mixing drum 10 by fixed hinges. When it is necessary to open the mixing drum 10 to change the cutter or check the coarse aggregate processing, the safety lock installed on the outer edge of the left compartment door 19 or the right compartment door 21 must be released, and the manual opening handle in the middle of the corresponding compartment door must be grasped to drive the compartment door (19 or 21) to rotate smoothly outward around the axis of its fixed hinge. The compartment door is designed with a sufficient opening angle to facilitate operations such as cutter replacement, aggregate inspection, or cavity cleaning. After the operation is completed, the hopper door is pushed back to its original position, ensuring it fits tightly against the mixing drum 10. Four spiral ribs 17 are evenly spaced inside the mixing drum 10. The spiral ribs 17 push the material forward in the opposite direction to the main shaft 32, allowing for material backflow and thorough grinding of the aggregates. The main shaft 32 rotates much faster than the mixing drum 10, and under the continuous pushing action of the aggregates from the rear, although the aggregates tend to retreat, the overall trend is still towards the discharge port. In the crushing system of the mixing drum 10, the high-speed rotation of the main shaft 32 repeatedly impacts the aggregates against the drum wall area through collisions, creating an impact crushing effect. To further enhance this mechanical stripping effect, the inner surface of the mixing drum 10 is equipped with a removable array of wear-resistant nails 20 made of hard alloy. This array is densely arranged, ensuring service life while significantly improving material stripping efficiency through multi-point impact. The multi-angle impact significantly improves the efficiency of aging asphalt removal, increases the degree of coarse aggregate crushing, and enables the material to achieve the best processing effect under the action of impact, shearing and grinding.The right end of the mixing drum 10 extends into the right fixed box mixing drum extension end 29. The centrifugal force generated by the rotation of the drum body drives the aggregate to throw out the processed aggregate and discharge it from the main discharge port 15.

[0044] like Figure 1 , Figure 4 , Figure 5As shown, the fixing device provided in this embodiment includes a left fixing box 2, a lifting lug 3, a square steel support beam 4, a roller 5, a shaft gear 6, a thin shaft 7, a right fixing box 8, a bottom support frame 11, an auxiliary square steel beam 12, a main feed inlet 13, a main discharge outlet 15, a left fixing box feed inlet 24, a left fixing box thin shaft support end 25, a left fixing box main shaft support end 26, a right fixing box thin shaft support end 27, a right fixing box main shaft support end 28, a stirring drum extension end 29, a motor shaft support end 30, and a self-aligning roller bearing support device 47. During operation, the high-speed rotation of the main shaft 32 and the low-speed rotation of the stirring drum 10 will generate a large moment of inertia. Furthermore, according to dynamic analysis, when the mixing drum 10 is fully loaded (typically 60-70% of its volume), the centrifugal force generated by its rotating mass can reach 3-5 times the total weight of the equipment. Combined with the intense collisions and friction between the aggregates, these enormous dynamic loads will primarily act on the main shaft 32 system, bearing support structure, and cavity connectors, posing a significant threat to the stability and safety of the equipment during operation. Therefore, a corresponding fixing device was specifically designed to address this issue. This device uses a left fixing box 2 and a right fixing box 8 as the core support and fixing structure. Between the left fixing box 2 and the right fixing box 8 are three thin shafts 7 and two square steel support beams 4. The thin shaft support ends 25 and 27 of the left and right fixing boxes are used to install the thin shafts 7. The rollers 5 are U-shaped, and the rollers 5 on the thin shafts 7 can cooperate with the outer raceway 18 on the mixing drum 10 through a concave-convex structure, preventing axial movement and radial runout of the mixing drum. In addition, the thin shaft 7 also serves as a gear shaft, with a shaft gear 6 located in its middle. The shaft gear 6 engages with the large gear ring 14 on the mixing drum 10, and its rotation drives the rotation of the mixing drum 10. The thin shaft 7 supports the mixing drum 10, and the force of the aggregate is transmitted to the three thin shafts 7 through the mixing drum 10. Therefore, the thin shaft 7 must withstand a large radial force. The thin shaft 7 can be mounted on the fixed housing using precision-grade double-row tapered roller bearings, forming a stable triangular support system. To ensure the rigidity and stability of the overall structure, two bottom support frames 11 are installed at the bottom of the two side housings, pre-tightened with high-strength bolts and connected to the fixed housing. At the same time, two square steel support beams 4 are added to the top of the two fixed housings to mitigate axial impact. The square steel support beams 4 are pre-tightened with bolts and connected to the left and right fixed housings. Three auxiliary square steel beams 12 are welded between the bottom support frames 11 to improve the torsional stiffness in the width direction. On each side of the large gear ring, there is a self-aligning roller bearing support device 47 to bear the axial and radial forces on the mixing drum 10. The self-aligning roller bearing support device 47 is fixed to the bottom support frame 11 by high-strength bolts at its bottom. This fixing device meets the reliable operation requirements of the equipment under long-term high-load conditions. The overall structural design takes into account the coordinated optimization of static stiffness and dynamic stiffness, effectively controlling vibration while ensuring load-bearing capacity.The interior of the left fixed box 2 is designed with a slightly inclined cavity. Coarse aggregate flows through this cavity to the main feed inlet 13 and then into the mixing drum 10. The front face of the right fixed box 8 has a mixing drum insertion end 29, which is larger than the outer diameter of the mixing drum 10. The right end of the mixing drum 10 extends into the mixing drum insertion end 29. The aggregate is thrown out onto the inclined surface of the right fixed box 8 by centrifugal force and finally flows out from the main discharge outlet 15. There are four lifting lugs 3 on the top of the two fixed boxes. The device can be lifted and placed into a standard container by a lifting device for rapid deployment.

[0045] like Figure 1 , Figure 7As shown, the transmission system provided in this example includes a conveyor 1, a motor 9, a coupling 38, a motor shaft 39, a belt drive system ① 40, a clutch 41, a pinion 42, a large gear 43, a large gear shaft 44, a belt drive system ② 45, and a pinion shaft 46. The screened coarse aggregate is transported to the left fixed box feed inlet 24 via the conveyor 1. A weighing roller is installed below the conveyor 1, connected to a high-precision strain gauge load cell to monitor the weight of the aggregate passing through the conveyor in real time. A non-contact encoder is installed on the conveyor as a speed sensor to monitor the actual operating speed of the conveyor in real time. The mass flow rate can be roughly calculated using the mass signal from the load cell and the speed signal from the speed sensor, thus calculating approximately how many tons of coarse aggregate the device can process per hour. The selected motor 9 is a high-power three-phase asynchronous motor, and a frequency converter is used to control the output speed. The motor 9 inputs torque to the motor shaft 39 via the coupling 38, and the motor shaft 39 is mounted on the right fixed box motor shaft support end 30. The motor shaft 39 has a small pulley end with a belt drive system ① 40 and a driving end with a clutch 41. The motor shaft 39 and the pinion shaft 46 are coaxial and can be connected and disconnected through the clutch 41. When the two shafts are disconnected, the motor shaft 39 only transmits power to the main shaft 32 through the belt drive system ① 40. At this time, only the main shaft 32 rotates while the stirring drum 10 does not rotate. The large gear shaft 44 and the small gear shaft 46 are both installed in the right fixed box 8, and they are both fitted with cylindrical roller bearings. The small gear 42 on the small gear shaft 46 meshes with the large gear 43 according to a certain tooth ratio. The small gear 42 has fewer teeth than the large gear 43, achieving speed reduction transmission. The large gear shaft 44 has a large gear 43 and a small pulley end with a belt drive system ② 45. Its large pulley end is located at the foremost end of the thin shaft 7. Thus, when the motor shaft 39 and the pinion shaft 46 are connected, the torque of the motor 9 is transmitted to the thin shaft 7 through the clutch 41, pinion 42, large gear 43, and belt drive system ② 45. The shaft gear 6 on the thin shaft 7 engages with the large gear ring 14 on the stirring drum 10, thereby realizing the rotation of the stirring drum 10. When the input speed of the motor 9 is increased or decreased, the speed of the main shaft 32 and the stirring drum 10 will also increase or decrease synchronously. The main shaft 32 and the motor 9 rotate in the same direction, the thin shaft 7 and the motor 9 rotate in opposite directions, and the stirring drum 10 and the motor 9 rotate in the same direction. If the rotation direction of the motor 9 is clockwise when viewed from the right fixed box 8 to the left fixed box 2, then the rotation direction of the main shaft 32 is clockwise, the rotation direction of the thin shaft 7 is counterclockwise, and the rotation direction of the stirring drum 10 is clockwise. The main shaft 32 pushes the aggregate towards the discharge port, and the mixing drum 10 achieves a reflux effect on the aggregate. The spiral blades 34 adopt a right-handed design, and the spiral ribs 17 adopt a left-handed design. If the motor reverses, the spiral blades 34 must adopt a left-handed design, and the spiral ribs 17 must adopt a right-handed design.

[0046] Example 2: This embodiment provides a working method for a mobile box-type asphalt milling material fine stripping device, including the following steps: After the equipment is transported to the site, it is quickly deployed using lifting equipment. Once in place, the equipment is temporarily secured, and the lifting slings are released before entering the equipment commissioning phase. Motor 9 is turned on, and the operation of the main shaft 32 and mixing drum 10 is observed to ensure normal operation. After ensuring normal operation, the screened asphalt milling material is transported via conveyor 1 to the left fixed box inlet 24. The coarse aggregate enters the mixing drum 10 after passing through the internal flow channel of the left fixed box 2, and is conveyed towards the mixing drum outlet 22 by the spiral conveyor action of the main shaft 32. After gaining circumferential velocity through the high-speed mixing action of the main shaft 32, the coarse aggregate undergoes parabolic motion and collides with the wear-resistant nails 20. Friction generates shearing force to remove the aged asphalt from the surface. The wear-resistant nails 20 protect the inner surface of the mixing drum 10. The main shaft 32 also scrapes the aged asphalt on the surface of the coarse aggregate. A certain gap is left between the cutter and the inner surface of the mixing drum 10. When coarse aggregate accumulates at this point, the rapidly rotating cutter applies cutting force to the aged asphalt to achieve cutting. To enhance the collision between coarse aggregates and improve the extrusion and grinding effect, two sets of agitators are installed on the main shaft 32. When the aggregates are transported here, they are subjected to circumferential impact, giving them more kinetic energy to collide with other aggregates, the inner surface of the mixing drum 10, and the wear-resistant nails 20. To promote better material circulation, the direction in which the main shaft 32 propels the material is opposite to the direction of the spiral ribs 17. The spiral ribs 17 give the aggregates a tendency to flow back, increasing the possibility of multiple collisions between the aggregates. However, the rotational speed of the main shaft 32 is greater than that of the mixing drum 10, so the overall direction of aggregate transport is still the direction of the main shaft 32. After the aggregates and aged asphalt are transported to the right end of the mixing drum 10, they are thrown onto the inclined surface of the right fixed box 8 by centrifugal force and the extrusion action of the main shaft 32, and flow out through the main discharge port 15.

[0047] The aggregate flowing out of the main discharge port 15 can be processed by an additional screening device.

[0048] Within the mixing drum 10, the coarse aggregate undergoes compression, grinding, scraping, and impact crushing, achieving refined stripping of aged asphalt from the surface of the large-diameter coarse aggregate. During operation, the device can continuously feed material into the left fixed box inlet 24, enabling continuous and efficient processing of the milled material.

[0049] Once the operation is completed, the device can be repacked into a container for transportation, thus achieving portable processing of the device.

[0050] The above are merely preferred embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A mobile box-type asphalt milling material fine stripping device, characterized in that, include: The spiral stripping device includes a main shaft arranged along the central axis of the mixing drum, and spiral blades are welded on the main shaft. The spiral blades directly act on the coarse aggregate entering the mixing drum. When the main shaft rotates at high speed, the coarse aggregate impacts the inner wall of the mixing drum, forming an impact-grinding synergistic peeling mechanism. The mixing drum has spiral ribs on its inner wall that rotate in the opposite direction to the spiral blades of the main shaft, so that the material is subjected to both axial propulsion force and drum back thrust. The fixing device includes a torsion-resistant box-shaped structure consisting of double-sided box bodies connected by three thin shafts, a bottom I-beam support frame, and a top square steel support beam; the three thin shafts are evenly distributed and installed on the left and right fixed box bodies along the circumference; the thin shafts are equipped with concave rollers to form a rolling fit with the outer raceway of the cylinder; the bottom double I-beam frame is welded to three auxiliary square steels, and the top two square steel support beams are pre-tightened to the box bodies by bolts; The transmission device drives the main shaft and the stirring drum to rotate in the same direction. The outer edge of the spiral blades is equipped with a detachable cutter, and the main shaft is equipped with a stirring device to prevent accumulation. The inner wall of the mixing drum is welded with an array of wear-resistant nails, and the inlet and outlet adopt a non-contact structure. The spindle speed is greater than the stirring drum speed; The spiral blades on the main shaft propel the aggregate axially toward the discharge end, while the spiral ribs on the inner wall of the mixing drum push the aggregate back toward the feed end, causing the aggregate to flow back inside the mixing drum. Under the condition that the spindle speed is greater than the mixing drum speed, the aggregate moves as a whole toward the discharge end while generating backflow; The main shaft is welded with four sets of right-handed helical blades, and the inner wall of the stirring drum is provided with four left-handed helical ribs; Two sets of stirring devices are welded onto the main shaft. The stirring devices are located between adjacent spiral blades to agitate the material between the spiral blades and enhance the collision between the material. Coated cutting tools are mounted on the outer tool holder of the spiral blades. Circular tooth cutting tools are configured at the outer ends of the spiral blades in the inlet / outlet sections, and pointed tooth cutting tools are configured in the middle section. The tool body is made of high-speed steel, and the cutting zone has a cemented carbide coating structure.

2. The mobile box-type asphalt milling material fine stripping device as described in claim 1, characterized in that, The stirring drum is provided with a large toothed ring on its outer periphery, and outer raceways are provided on both sides of the large toothed ring; The three thin shafts are respectively equipped with shaft gears and concave rollers. The concave rollers form a concave-convex rolling fit with the outer raceway to support the stirring drum and prevent the stirring drum from axial movement and radial runout. The shaft gears mesh with the large gear ring to drive the stirring drum to rotate. The transmission device includes: The motor drives the main shaft to rotate via a belt pulley, and the gear set is linked by a clutch, with the shaft gear meshing with the large gear ring to drive the cylinder to rotate. The tool assembly configuration process includes: Countersunk holes are made at intervals in the tool holder, and high-strength bolts are used to fix the round tooth tool and the pointed tooth tool; The pointed tooth cutter is arranged in the two middle sets of helical blades, and the round tooth cutter is arranged in the two end sets of helical blades; The material stripping process includes: The aggregate is subjected to centrifugal impact from the main shaft against the wear-resistant nails and the cylinder wall, achieving stone-on-iron separation; The collision of aggregates produces stone-on-stone grinding; A toothed cutting tool scrapes away the asphalt layer on the surface of the aggregate; The continuous processing includes: After screening, the coarse aggregate is conveyed into the cylinder through the feed inlet of the left fixed box via a conveyor. After processing, the material is centrifugally ejected from the right end of the cylinder and then discharged through the inclined flow inside the right fixed box. The top lifting lugs on both sides of the container are suitable for standard container transportation.

3. A working method for a mobile box-type asphalt milling material fine stripping device, characterized in that, For implementing the mobile box-type asphalt milling material fine stripping device as described in any one of claims 1-2, the working method includes: The screened coarse aggregate is conveyed to the feed inlet of the left fixed box by a conveyor, and then enters the mixing drum after passing through the internal flow channel of the left fixed box. Start the transmission device to make the main shaft and the stirring drum rotate in the same direction, and the main shaft speed is greater than the stirring drum speed. The spiral blades on the main shaft and the spiral ribs on the inner wall of the stirring drum have opposite spiral directions. The coarse aggregate is axially propelled toward the discharge end by the helical blades on the main shaft, while the coarse aggregate is pushed back toward the feed end by the helical ribs on the inner wall of the mixing drum. This causes the coarse aggregate to flow back inside the mixing drum. Under the condition that the rotational speed of the main shaft is greater than the rotational speed of the mixing drum, the coarse aggregate moves toward the discharge end as a whole while flowing back. During the process of coarse aggregate reflow and moving towards the discharge end, the rotation of the main shaft and mixing drum causes the coarse aggregate to collide with the inner wall of the mixing drum and wear-resistant nails, and causes the coarse aggregate to collide, squeeze and rub against each other to peel off the aged asphalt on the surface of the coarse aggregate. The processed aggregates and asphalt are discharged from the outlet through the conveying of the main shaft and the centrifugal force of the processing chamber; The discharged aggregate and asphalt are separated by a screening device to obtain coarse aggregate and asphalt.

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