Mechanical quantitative controllable shot blasting device and shot blasting method

Abstract

The invention relates to a mechanical quantitative controllable shot blasting device and a shot blasting method, and belongs to the technical field of metal surface strengthening. The full-mechanized process of raw material caching, intelligent shunting, ordered arrangement, mechanical acceleration and qualified projectile closed-loop recovery is adopted, and real-time feedback regulation and control of a central controller are combined, so that projectiles are supplied, sorted, directionally accelerated and recycled; the method comprises the steps of raw material feeding and caching, intelligent flow dividing and flow regulation and control, ordered projectile arrangement and transmission, mechanical roller directional acceleration and output and recovery, and accurate cooperative control over flow dividing parameters, vibration frequency and roller rotating speed through a central controller. Independent quantitative regulation and control of shot supply flow, single shot ejection speed, impact times per unit time and impact direction are achieved, meanwhile, the material utilization rate is increased through qualified shot recovery circulation, and controllability, consistency and economical efficiency of shot peening strengthening are remarkably enhanced. And an efficient technical approach is provided for accurate design of the residual stress field on the metal surface.

Description

Technical Field

[0001] This invention relates to a mechanical quantitative controllable shot peening device and method, belonging to the field of metal surface strengthening processing technology. Background Technology

[0002] Shot peening, as one of the most widely used surface cold working technologies, works by continuously impacting the workpiece surface with a high-speed stream of shot. This introduces a residual compressive stress layer and work hardening effect, significantly improving the workpiece's fatigue strength, resistance to stress corrosion, and fretting wear resistance. This technology has long played a crucial role in key industrial sectors such as aerospace, automotive manufacturing, and energy equipment.

[0003] Currently, mainstream shot peening equipment mainly employs pneumatic or centrifugal acceleration technologies. Pneumatic systems rely on compressed air to accelerate the shot, while centrifugal systems use high-speed impellers to propel the shot. However, both of these traditional technologies have inherent limitations. The impact process exhibits significant disorder and statistical characteristics; the shot is in a turbulent state within the airflow or centrifugal force field, and its impact on the workpiece is random and unpredictable. The process effectiveness depends entirely on the statistical results of a large number of shot impacts.

[0004] Furthermore, the setting and optimization of traditional shot peening process parameters heavily rely on engineers' experience and extensive experimental verification, resulting in high trial-and-error costs and difficulty in ensuring consistent treatment effects across different batches of workpieces. A more fundamental limitation is that traditional technology cannot achieve precise control over the impact energy and position of a single shot, making it difficult to quantitatively and selectively strengthen specific micro-areas on complex workpieces, nor can it achieve patterned strengthening with customized gradient effects.

[0005] Although existing technologies attempt to optimize the process through methods such as robot path planning and real-time parameter monitoring, they do not change the inherently "disorderly" nature of projectile impact. Therefore, developing a new shot peening technology capable of achieving ordered, quantitative, and controllable projectile impact has become a critical technological bottleneck that the industry urgently needs to overcome. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a mechanically controlled quantitative shot peening method and apparatus. This method aims to fundamentally change the acceleration and impact mode of shot, solving the problems of disordered shot impact, parameter dependence on experience, and inability to achieve quantitative and precise local strengthening in traditional pneumatic shot peening processes. It also overcomes the deficiencies of existing mechanical shot peening solutions, such as fluctuating feed flow and low shot utilization. By using mechanical means to achieve independent and precise control of the velocity and frequency of individual shot, the shot peening process becomes digitalized, precise, and controllable.

[0007] The technical solution of the present invention is as follows: The core of the technical solution proposed in this invention lies in completely abandoning the traditional principles of airflow acceleration or centrifugal projection, and instead adopting a fully mechanized process of "raw material buffering - intelligent diversion - orderly sorting - mechanical acceleration - recycling" to supply, regulate, and accelerate the shot, thereby achieving precise digital control of the shot peening process. This method, by introducing intelligent diversion and closed-loop recycling, further solves the fundamental problems of shot flow fluctuations, disordered movement, and difficulty in quantitatively controlling parameters in traditional processes.

[0008] A mechanical quantitative controllable shot peening device includes a hopper, the outlet of which is connected to at least two diversion channels. An intelligent diversion module is provided at the connection between the outlet of the hopper and the diversion channels. The intelligent diversion module is equipped with a photoelectric counter to collect shot flow data in real time. The diversion channel is connected to the spiral vibrating plate, which is used to form disordered projectiles into a single-row line of projectiles. The discharge port of the spiral vibratory feeder is connected to a linear channel, and an acceleration roller assembly is installed at the end of the linear channel. The acceleration roller assembly is used to accelerate the projectile through, forming an impact projectile flow.

[0009] Preferably, the intelligent diversion module also includes an electromagnetic valve, which is placed at the inlet of each diversion channel. The on / off state of the electromagnetic valve is adjusted to control the flow rate of the projectile into the corresponding diversion channel.

[0010] Preferably, the spiral vibratory feeder is a semi-enclosed spiral guide rail structure, including a circular base, a continuously rising spiral guide rail on the base, and an annular barrier above the guide rail to prevent projectiles from splashing.

[0011] More preferably, the height of the annular barrier is 2-3 times the maximum diameter of the projectile.

[0012] Further preferably, the helical guide rail has an inclination angle of 15°-20° relative to the horizontal plane, tilting outwards along the spiral upward direction to ensure that the projectile rises along the guide rail during vibration without slipping. The helical guide rail is an open groove, with a groove depth (vertical distance from the bottom to the opening) of 1.2-1.5 times the maximum diameter of the projectile, accommodating only single projectiles stacked together to avoid disordered arrangement. The helical guide rail has 3-5 turns, with a minimum turning radius of 5-8 times the maximum diameter of the projectile. The groove width narrows uniformly from bottom to top, with the bottom groove width being 3-4 times the maximum diameter of the projectile and the top groove width being 1.1-1.2 times the maximum diameter of the projectile. This design ensures sufficient space for projectile attitude adjustment while preventing projectile splashing through the enclosure. This process utilizes the principle of electromagnetic vibration.

[0013] Preferably, the discharge port of the spiral vibratory feeder is connected to the linear channel by a flexible coupling, which can swing around the connection point within a range of ±15° to adapt to different impact direction requirements, and a sealing gasket is set at the connection to prevent shot from splashing.

[0014] Preferably, the cross-sectional shape of the straight channel matches the shape of the projectile, the inner diameter of the straight channel is 0.05 mm larger than the diameter of the projectile, and the inner wall of the channel is polished or coated with anti-friction materials such as polytetrafluoroethylene, which significantly reduces the transmission resistance, ensures that the projectile always maintains the predetermined formation and orientation, and completely avoids disorder or jamming during the conveying process.

[0015] Preferably, the acceleration roller assembly consists of two parallel rollers, with V-shaped annular guide grooves machined on the meshing surfaces of the two rollers. The V-angle is 60°-90°, and the groove walls are polished. These grooves are used to guide the projectile to accelerate in a centered manner, while also being adaptable to oblique incidence within a range of ±15°. The roller surfaces are coated with a layer of materials such as tungsten carbide, ceramic, or high wear-resistant alloy steel (e.g., tungsten carbide coating sintered using powder metallurgy, with a hardness of HRA90 or higher), which ensures both wear resistance and provides a stable coefficient of friction.

[0016] The acceleration roller assembly is fixed to the base of the device and cannot swing. Its core function is to provide directional acceleration force to the projectile without changing the projectile's direction of motion. The final ejection direction of the projectile is determined by the orientation of the straight channel.

[0017] Preferably, the exit of the straight channel maintains a fixed distance of 5-8mm from the acceleration roller assembly.

[0018] Preferably, the mechanical quantitative controllable shot peening device also includes a flexible sleeve assembly, which includes a bending part and a connecting part. The bending part is a flexible structure of nickel-titanium shape memory alloy. The injection angle is completely determined by its own bending posture. It is not a rigidly fixed bend and can be manually bent to any angle within the range of 0°-90°. After being released, it automatically sets its shape (angle deviation ≤1°) to adapt to the spraying requirements of different directions. The curved section has a smooth, continuous circular channel with a diameter matching the inner diameter of the straight channel (projectile diameter + 0.05mm). The inner wall is coated with a PTFE friction-reducing layer to ensure smooth, unobstructed projectile passage. The quick-release function utilizes a dual structure of external threads and elastic clips. The connecting part has internal threads and an annular groove, while the straight channel outlet has matching external threads and elastic clip protrusions. During installation, align the connecting part inlet with the straight channel outlet and rotate clockwise 3-5 times to lock the threads. Simultaneously, the elastic clip protrusion engages with the annular groove for secondary fixation (coaxiality deviation ≤ 0.02mm). For disassembly, press the clip protrusion and rotate counter-clockwise for quick removal; replacement time ≤ 30 seconds. The straight channel outlet and the curved section inlet are located on opposite sides of the accelerating roller assembly. The projectile ejected from the straight channel is accelerated by the accelerating roller assembly before entering the curved section channel and exiting from the curved section outlet to the designated direction and area.

[0019] Compared to conventional projectile-ejecting spray guns, which often integrate pneumatic acceleration functions, are large in size, lack flexibility, and rely on the overall rotation of the spray gun for directional adjustment, making it difficult to penetrate deep cavities or conform to complex curved surfaces, the sleeve of this invention only serves a "directional guidance" function and does not have an acceleration module. It is small in size (outer diameter ≤10mm), flexible and bendable, and can be extended into narrow spaces. Furthermore, through the aforementioned quick-release structure, it can quickly connect with the linear channel. Combined with the ±15° fine oscillation of the linear channel, it forms a synergistic directional logic of "coarse adjustment (sleeve bending) + fine adjustment (channel oscillation)" without changing the acceleration kinetic energy of the projectile, ensuring consistency in spray accuracy and strengthening effect.

[0020] Preferably, the mechanical quantitative controllable shot peening device also includes a central controller, which is connected to an intelligent diversion module, a spiral vibratory feeder, a linear channel, and an acceleration roller assembly. The intelligent diversion module feeds back the real-time collected shot flow data to the central controller. The central controller adjusts the solenoid valve according to the preset diversion parameter command (response speed ≤ 50ms). The central controller sends a vibration frequency command (50-200Hz) to the spiral vibratory feeder. The linear channel is equipped with an oscillating driver, and the central controller controls the oscillation of the linear channel. The central controller controls the rotation speed (2000-3000r / min) of the acceleration roller assembly through the roller speed adjustment drive unit.

[0021] Preferably, the mechanical quantitative controllable shot peening device also includes a recovery device, which includes an annular recovery tank surrounding the workpiece, a sorting component, and a return pipe. The width of the recovery tank is 5-8 times the maximum diameter of the shot, and the depth is 3-4 times the maximum diameter of the shot. A guide plate with an inclination angle of 30°-45° is installed on the inner side of the tank. Shots that miss the workpiece fall directly into the recovery tank, while shot that hits the workpiece and bounces back is guided by the guide plate to flow into the tank without any omissions, avoiding shot splashing or residue. The sorting component adopts a dual screening mechanism of "visual inspection + ultrasonic inspection" - including a visual inspection module (resolution ≥ 10 million pixels, detection accuracy ≤ 0.01 mm) to identify cracks, deformation and other damage on the surface of the shot in real time; and an ultrasonic inspection module (detection frequency 5-10 MHz, detection depth ≥ 0.1 mm) to identify hidden cracks, inclusions and other defects inside the shot. The collaborative misjudgment rate of the dual inspection is required to be no higher than 0.5%. All of these use commercially available components, such as Keyence IV4-G500CA. The sorting component sorts out qualified and undamaged bullets, which are then returned to the silo through the return pipeline, forming a closed-loop supply. The sorting component feeds back the pass rate to the central controller in real time.

[0022] A shot peening method using a mechanically controlled quantitative shot peening device includes the following steps: S1 Raw Material Feeding and Buffering During this stage, a large number of disordered projectiles are fed into the silo for buffering. The capacity of the silo matches the processing rhythm of subsequent modules, which can avoid instantaneous fluctuations in projectile supply; at the same time, the silo receives the feeding rhythm instructions issued by the central controller and outputs projectiles to the intelligent diversion module as needed, laying a stable supply foundation for subsequent precise diversion and control.

[0023] S2 Intelligent Diversion and Flow Control The shot output from the hopper first enters the diversion area of ​​the intelligent diversion module. The photoelectric counter in this module collects shot flow data in real time and feeds it back to the central controller, accurately capturing the shot flow rate. The central controller issues diversion parameter commands based on preset shot peening process parameters, adjusting the on / off state of the solenoid valves to control the flow rate of shot entering the corresponding diversion channel. This ensures that the shot supply matches the processing capacity of the subsequent orderly sorting and acceleration modules, preventing supply congestion or flow interruptions.

[0024] S3 orderly sorting and stable transmission After being diverted, the projectiles are guided into a spiral vibratory feeder. The vibration intensity is controlled by the vibration frequency command issued by the central controller, so that when the disordered projectiles rise along the spiral guide rail, they gradually complete the process of "attitude calibration (center of the projectile aligns with the guide rail axis) → speed pre-control (uniform speed of 1-2 m / s) → single-row queuing", and finally form a continuous and uniform single-row queue.

[0025] Without the helical vibratory feeder, the narrowing of the channel would not solve the problem of congestion and jamming of disordered projectiles, and would not achieve uniformity of attitude and velocity, leading to excessive kinetic energy deviation during subsequent roller acceleration and compromising the quantitative controllability. The helical vibratory feeder, on the other hand, lays the foundation for stable transmission and precise acceleration. Subsequently, a single row of projectiles is guided into a linear channel driven by a linear vibrator.

[0026] S4 Mechanical Roller Directional Acceleration and Output The linear channel is connected to the helical vibratory feeder via a "flexible coupling + rotary damping hinge". The channel swing command issued by the central controller regulates the swing driver, so that the linear channel can swing in pitch within a range of ±15°. The projectile is stably transmitted along the axial direction in the linear channel (speed 1-2m / s), and its initial motion direction is adjusted synchronously with the channel swing. The orderly projectiles, transported stably, are precisely guided to the meshing inlet of the acceleration roller assembly. The straight channel outlet maintains a fixed distance of 5-8 mm from the roller meshing area and is always aligned with the center area of ​​the V-shaped guide groove. After the projectiles are obliquely injected along the axis of the straight channel, they first contact the V-shaped groove wall of one side of the roller. The lateral constraint force provided by the groove wall guides the projectiles to the center of the meshing area. At this time, the rollers energize the projectiles through friction and compression—the direction of friction is superimposed on the initial motion direction of the projectiles (rather than horizontal correction). Finally, the projectiles accelerate while maintaining the initial oblique direction, and the speed increases from 1-2 m / s to 50-100 m / s.

[0027] Meanwhile, the central controller regulates the roller speed control drive unit to keep the two rollers rotating in precise synchronization (synchronization accuracy ±0.1%), ensuring that the projectile can obtain uniform friction regardless of the angle from which it enters, thus guaranteeing the consistency of the kinetic energy of a single projectile (speed deviation ≤ ±2%).

[0028] After the projectile enters the meshing zone, it is subjected to the squeezing and friction of the roller surface, and obtains directional high-speed kinetic energy directly related to the linear velocity of the roller. The projectile has a velocity of 0.5-1m / s in the diversion channel and 1-2m / s in the straight channel. After passing through the acceleration roller group, the velocity can reach 50-100m / s, and finally form an ordered projectile flow with a preset speed and direction. It can be directly output in basic scenarios, and output in complex scenarios by adding a quick-release flexible sleeve assembly (the sleeve is an optional accessory, which is connected to the straight channel outlet through a threaded + snap structure, and can be quickly disassembled and assembled, adapting to reinforcement requirements such as deep cavities, large angles, and complex curved surfaces).

[0029] After output, all projectiles (including those that miss the workpiece and those that bounce back after hitting the workpiece) are collected by the recycling device. The core logic is that projectiles that hit the workpiece but do not cause damage still have reuse value. Deliberately distinguishing them would increase the complexity of the equipment and cause material waste. Therefore, a "full collection + precise screening" design is adopted, which only removes damaged projectiles by detection and retains all qualified projectiles for return and reuse.

[0030] The sorting unit guides damaged shot into the waste box, while qualified shot flows back to the silo through a return pipe (the inner wall is coated with a polytetrafluoroethylene friction-reducing layer, and the pipe diameter is 3-4 times the maximum shot diameter), forming a closed-loop supply.

[0031] This closed-loop design not only improves the utilization rate of the shot (single-time recovery qualification rate ≥95%), but also avoids damaged shot entering the process and affecting the shot peening effect. At the same time, the central controller monitors the qualification rate of the recovered shot in real time. When the qualification rate is lower than 90%, it automatically reduces the roller speed (each reduction amount ≤5%) or adjusts the vibration frequency to help optimize the shot peening process parameters and ensure processing stability.

[0032] This invention uses a central controller (PLC / industrial computer) as its core. The process is as follows: A large number of disordered projectiles enter the silo for buffering (qualified projectiles can be recycled through a return pipe). The projectiles enter the intelligent diversion module through a conveying channel (the pipe diameter is 3-4 times the maximum particle size of the projectiles). A photoelectric counter collects the projectile flow data in real time and feeds it back to the central controller. The controller adjusts the solenoid valve according to the preset diversion parameter command (response speed ≤50ms) so that the projectiles enter the diversion channel at a flow rate matching the processing capacity of the subsequent modules. The projectiles in the diversion channel enter the spiral vibratory feeder. The central controller issues a vibration frequency command (50-200Hz) to sort the projectiles into a single uniform queue. Then, the projectiles enter the linear channel driven by the linear vibrator for further attitude calibration and feedback of sorting data (speed 1-2m / s, attitude consistency deviation ≤0.02mm). The projectiles passing through the linear channel are precisely guided to the meshing inlet of the acceleration roller group (the channel outlet and the roller meshing area are fixedly spaced 5-8mm apart, aligned with V). The guide groove center) and the central controller synchronously adjust two key parameters: first, the linear channel is controlled to swing horizontally within a range of ±15° by the linear channel angle adjustment unit (flexible coupling + rotational damping hinge structure); second, the speed of the acceleration roller group is controlled by the roller speed control drive unit (2000-3000r / min). The dual control works together to control the trajectory direction and velocity of the projectile. The projectile accelerated by the acceleration roller group (final velocity 50-100m / s) forms a single-row orderly projectile flow. In basic scenarios, it is directly output as a projectile flow. In complex scenarios (deep cavity, large angle, complex curved surface reinforcement), a quick-release flexible sleeve assembly can be added.

[0033] After the sleeve assembly is added, the straight channel still has the swing function: when the sleeve is adapted to a workpiece with a complex curved surface, the channel swing can compensate for the angle deviation after the sleeve is bent, ensuring that the shot flow is always perpendicular to the workpiece surface; at the same time, the swing function can adapt to sleeves with different bending angles, improving the adaptability of the device to a variety of workpieces. The two functions complement each other rather than replace each other.

[0034] Finally, the velocity sensor feeds back the projectile velocity data to the central controller in real time, achieving closed-loop control throughout the entire process.

[0035] This application focuses on "precise and controllable single shot" as its core objective, reconstructing the entire shot peening process logic. It achieves for the first time four independent quantitative controls of "shot supply flow rate, single shot velocity, impact frequency per unit time, and impact direction," completely breaking the limitations of existing patents, which can only regulate shot flow rate, focus on monitoring the processing process but cannot control the kinetic energy of single shots, and rely on multi-size mixing for strengthening but lack ordered design. Through the "counting-feedback-dynamic control" closed loop of the intelligent diversion module, the "sorting-speed pre-control-attitude calibration" coordination of the spiral vibratory feeder, the "precise speed control of single-row shot friction" of the mechanical roller acceleration, the "detection-pass rate feedback-process optimization" linkage of the recovery unit, and the deep data communication between each module and the central controller, an inseparable organic whole is formed. This upgrades the shot peening process from traditional "disordered statistical strengthening" to "digital precision strengthening," filling the technical gap of existing technologies that cannot quantitatively and selectively strengthen specific areas of complex workpieces.

[0036] The beneficial effects of this invention are as follows: Compared with the prior art, the present invention has the following significant advantages: 1. Achieved quantitative controllability: For the first time in shot peening technology, independent, precise, and digital control of two core parameters, "single shot velocity" and "impact frequency," has been realized. The process parameters have moved from macroscopic statistics to microscopic quantification, laying the foundation for "digital shot peening."

[0037] 2. Excellent consistency and repeatability: Due to the high consistency of kinetic energy and impact interval of each projectile, the strengthening effect on the workpiece surface is uniform, the consistency of batch-produced workpieces is greatly improved, and the dependence on operator experience is completely eliminated.

[0038] 3. High energy efficiency: The energy transfer efficiency of mechanical contact acceleration is much higher than that of pneumatic acceleration, which reduces the energy consumption of compressed air and conforms to the concept of green manufacturing.

[0039] 4. Enables precise area strengthening: By combining with robots or CNC machine tools and sleeves of different specifications, high-speed concentrated shot streams can be precisely guided to specific areas of the workpiece (such as welds and fillets), achieving selective strengthening that traditional technologies cannot accomplish.

[0040] 5. High technical feasibility: The vibration sequencing, friction transmission and other technologies adopted are innovative integrations of mature technologies. Compared with electromagnetic acceleration and other solutions, the engineering implementation is less difficult and less costly, and the prospects for industrial application are clearer. Attached Figure Description

[0041] Figure 1 This is a closed-loop schematic diagram of the process flow of the mechanical quantitative controllable shot peening device of the present invention. Figure 2 This is a schematic diagram of the multi-channel parallel structure of the mechanical quantitative controllable shot peening device of the present invention; Figure 3 This is a schematic diagram of a customized, quick-release sleeve for the mechanical quantitative controllable shot peening device of the present invention. Among them, 1. a large number of disordered projectiles; 2. a hopper; 3. an intelligent diversion module; 4. a diversion channel; 5. a spiral vibratory feeder; 6. a straight channel; 7. an acceleration roller assembly; 8. a single-row ordered projectile flow; 9. a flexible sleeve assembly; and 10. a single-row ordered projectile flow with a specific orientation. Detailed Implementation

[0042] The present invention will be further described below with reference to the embodiments and accompanying drawings, but is not limited thereto.

[0043] Example 1 A mechanically controlled quantitative shot peening device, such as Figure 2-3 As shown, the system includes a hopper 2, with its outlet connected to at least two diversion channels 4. An intelligent diversion module 3 is installed at the connection between the hopper outlet and the diversion channels. This intelligent diversion module is equipped with a photoelectric counter to collect real-time projectile flow data. The diversion channels are connected to a spiral vibrating disc 5, which organizes the disordered projectiles into a single-row queue. The spiral vibrating disc's outlet is connected to a straight channel 6, with an acceleration roller assembly 7 installed at the end of the straight channel. This acceleration roller assembly accelerates the projectiles through, forming an impact projectile flow.

[0044] The intelligent diversion module also includes solenoid valves, which are placed at the inlet of each diversion channel. The on / off state of the solenoid valves is adjusted to control the flow rate of the projectile into the corresponding diversion channel.

[0045] The helical vibratory feeder is a semi-enclosed helical guide rail structure, including a circular base with a continuously rising helical guide rail on the base. A ring-shaped baffle is located above the guide rail to prevent projectile splashing. The height of the ring-shaped baffle is 2-3 times the maximum diameter of the projectile. The helical guide rail is tilted at an angle of 15°-20° relative to the horizontal plane, tilting outwards along the spiral direction to ensure the projectile rises along the guide rail during vibration without slipping. The helical guide rail has an open groove, with a groove depth (vertical distance from the bottom to the opening) of 1.2-1.5 times the maximum diameter of the projectile, accommodating only single projectiles stacked together to prevent disordered arrangement. The helical rail has 3-5 turns, with a minimum turning radius of 5-8 times the maximum diameter of the projectile. The groove width narrows uniformly from bottom to top, with the bottom groove width being 3-4 times the maximum diameter of the projectile and the top groove width being 1.1-1.2 times the maximum diameter of the projectile. This process, which ensures both space for projectile attitude adjustment and prevents projectile scattering through barriers, utilizes the principle of electromagnetic vibration.

[0046] The discharge port of the spiral vibratory feeder is connected to the linear channel by a flexible coupling, which can swing around the connection point within a range of ±15° to adapt to different impact direction requirements. A sealing gasket is set at the connection to prevent shot from splashing.

[0047] The cross-sectional shape of the straight channel matches the shape of the projectile. The inner diameter of the straight channel is 0.05 mm larger than the diameter of the projectile. The inner wall of the channel is polished or coated with anti-friction materials such as polytetrafluoroethylene, which significantly reduces transmission resistance and ensures that the projectile always maintains the predetermined formation and orientation, completely avoiding disorder or jamming during the transportation process.

[0048] The acceleration roller assembly consists of two parallel rollers. The meshing surfaces of the two rollers are machined with V-shaped annular guide grooves with a V-angle of 60°-90° and polished groove walls. These grooves are used to guide the projectile for centered acceleration and are also suitable for oblique incidence within a range of ±15°. The roller surfaces are coated with materials such as tungsten carbide, ceramics, or high wear-resistant alloy steel (e.g., tungsten carbide coatings sintered using powder metallurgy, with a hardness of HRA90 or higher), which ensures both wear resistance and provides a stable coefficient of friction.

[0049] The acceleration roller assembly is fixed to the base of the device and cannot swing. Its core function is to provide directional acceleration force to the projectile without changing the projectile's direction of motion. The final ejection direction of the projectile is determined by the orientation of the straight channel.

[0050] The exit of the straight channel maintains a fixed distance of 5-8mm from the acceleration roller assembly.

[0051] The mechanical quantitative controllable shot peening device also includes a flexible sleeve assembly, which includes a bending part and a connecting part. The bending part is a flexible structure of nickel-titanium shape memory alloy. The injection angle is completely determined by its own bending posture. It is not a rigid fixed bend. It can be manually bent and adjusted to any angle within the range of 0°-90°. After being released, it automatically sets its shape (angle deviation ≤1°) to adapt to the spraying needs of different directions. The curved section has a smooth, continuous circular channel with a diameter matching the inner diameter of the straight channel (projectile diameter + 0.05mm). The inner wall is coated with a PTFE friction-reducing layer to ensure smooth, unobstructed projectile passage. The quick-release function utilizes a dual structure of external threads and elastic clips. The connecting part has internal threads and an annular groove, while the straight channel outlet has matching external threads and elastic clip protrusions. During installation, align the connecting part inlet with the straight channel outlet and rotate clockwise 3-5 times to lock the threads. Simultaneously, the elastic clip protrusion engages with the annular groove for secondary fixation (coaxiality deviation ≤ 0.02mm). For disassembly, press the clip protrusion and rotate counter-clockwise for quick removal; replacement time ≤ 30 seconds. The straight channel outlet and the curved section inlet are located on opposite sides of the accelerating roller assembly. The projectile ejected from the straight channel is accelerated by the accelerating roller assembly before entering the curved section channel and exiting from the curved section outlet to the designated direction and area.

[0052] The mechanical quantitative controllable shot peening device also includes a central controller, which is connected to an intelligent diversion module, a spiral vibratory feeder, a linear channel, and an acceleration roller assembly. The intelligent diversion module feeds back the real-time shot flow data to the central controller. The central controller adjusts the solenoid valve according to the preset diversion parameter instructions (response speed ≤ 50ms). The central controller sends vibration frequency instructions (50-200Hz) to the spiral vibratory feeder. The linear channel is equipped with an oscillating driver, and the central controller controls the oscillation of the linear channel. The central controller controls the rotation speed (2000-3000r / min) of the acceleration roller assembly through the roller speed adjustment drive unit.

[0053] The mechanical quantitative controllable shot peening device also includes a recovery device, which consists of an annular recovery tank surrounding the workpiece, a sorting assembly, and a return pipe. The width of the recovery tank is 5-8 times the maximum diameter of the shot, and the depth is 3-4 times the maximum diameter of the shot. A guide plate with an inclination angle of 30°-45° is installed on the inner side of the tank. Shots that miss the workpiece fall directly into the recovery tank, while shot that hits the workpiece and bounces back is guided by the guide plate to flow into the tank without any omissions, avoiding shot splashing or residue. The sorting assembly adopts a dual screening mechanism of "visual inspection + ultrasonic inspection"—including a visual inspection module (resolution ≥ 10 million pixels, detection accuracy ≤ 0.01mm) to identify cracks, deformations, and other damage on the shot surface in real time; and an ultrasonic inspection module (detection frequency 5-10MHz, detection depth ≥ 0.1mm) to identify hidden cracks, inclusions, and other defects inside the shot. The collaborative misjudgment rate of the dual inspection is required to be no higher than 0.5%. All of these use commercially available components, such as Keyence IV4-G500CA. The sorting component sorts out qualified and undamaged bullets, which are then returned to the silo through the return pipeline, forming a closed-loop supply. The sorting component feeds back the pass rate to the central controller in real time.

[0054] Example 2 A shot peening method using the mechanical quantitative controllable shot peening device described in Example 1 includes the following steps: S1 Raw Material Feeding and Buffering During this stage, a large number of disordered projectiles 1 are fed into silo 2 for buffering. The capacity of the silo matches the processing rhythm of subsequent modules, which can avoid instantaneous fluctuations in projectile supply; at the same time, the silo receives the feeding rhythm instructions issued by the central controller and outputs projectiles to the intelligent diversion module as needed, laying a stable supply foundation for subsequent precise diversion and control.

[0055] S2 Intelligent Diversion and Flow Control The shot output from the hopper first enters the diversion area of ​​the intelligent diversion module 3. The photoelectric counter configured in this module collects shot flow data in real time and feeds it back to the central controller, accurately capturing the shot flow rate. The central controller issues diversion parameter commands according to the preset shot peening process parameters, adjusting the on / off state of the solenoid valves, thereby controlling the flow rate of shot entering the corresponding diversion channel 4. This achieves matching between the shot supply and the processing capacity of the subsequent orderly sorting and acceleration modules, avoiding material supply congestion or flow interruption.

[0056] S3 orderly sorting and stable transmission After being diverted, the projectiles are guided into the spiral vibratory plate 5. The vibration intensity is controlled by the vibration frequency command issued by the central controller, so that when the disordered projectiles rise along the spiral guide rail, they gradually complete the "attitude calibration (center of the ball aligns with the guide rail axis) → speed pre-control (uniform speed of 1-2m / s) → single-row queuing", and finally form a continuous and uniform single-row queue.

[0057] Without the helical vibratory feeder, the direct narrowing of the channel cannot solve the congestion and jamming problem of disordered projectiles, and it is impossible to achieve uniformity of attitude and velocity, which will lead to excessive kinetic energy deviation during subsequent roller acceleration, thus compromising the quantitative controllability effect; while the helical vibratory feeder can lay the foundation for subsequent stable transmission and precise acceleration. Subsequently, a single row of projectiles is guided into the linear channel 6 driven by the linear vibrator.

[0058] S4 Mechanical Roller Directional Acceleration and Output The linear channel is connected to the helical vibratory feeder via a flexible coupling and a rotary damping hinge. The channel swing command issued by the central controller regulates the swing driver, so that the linear channel can swing in a pitch range of ±15°. The projectile is stably transmitted along the axial direction in the linear channel (speed 1-2m / s), and its initial motion direction is adjusted synchronously with the channel swing.

[0059] The orderly projectiles, transported stably, are precisely guided to the meshing inlet of the acceleration roller group 7. The straight channel outlet maintains a fixed distance of 5-8mm from the roller meshing area and is always aligned with the center area of ​​the V-shaped guide groove. After the projectiles are obliquely injected along the axis of the straight channel, they first contact the V-shaped groove wall of one side of the roller. The lateral constraint force provided by the groove wall guides the projectiles to the center of the meshing area. At this time, the rollers energize the projectiles through friction and compression—the direction of friction is superimposed on the initial motion direction of the projectiles (rather than horizontal correction). Finally, the projectiles accelerate in the initial oblique direction, and the speed increases from 1-2m / s to 50-100m / s.

[0060] Meanwhile, the central controller regulates the roller speed control drive unit to keep the two rollers rotating in precise synchronization (synchronization accuracy ±0.1%), ensuring that the projectile can obtain uniform friction regardless of the angle from which it enters, thus guaranteeing the consistency of the kinetic energy of a single projectile (speed deviation ≤ ±2%).

[0061] After the projectile enters the meshing zone, it is subjected to the squeezing and friction of the roller surface, and obtains directional high-speed kinetic energy directly related to the linear velocity of the roller. The projectile has a velocity of 0.5-1m / s in the diversion channel and 1-2m / s in the straight channel. After passing through the acceleration roller group, the velocity can reach 50-100m / s, and finally form an ordered projectile flow with a preset speed and direction. It can be directly output in basic scenarios, and output in complex scenarios by adding a quick-release flexible sleeve assembly (the sleeve is an optional accessory, which is connected to the straight channel outlet through a threaded + snap structure, and can be quickly disassembled and assembled, adapting to reinforcement requirements such as deep cavities, large angles, and complex curved surfaces).

[0062] After output, all projectiles (including those that miss the workpiece and those that bounce back after hitting the workpiece) are collected by the recycling device. The core logic is that projectiles that hit the workpiece but do not cause damage still have reuse value. Deliberately distinguishing them would increase the complexity of the equipment and cause material waste. Therefore, a "full collection + precise screening" design is adopted, which only removes damaged projectiles by detection and retains all qualified projectiles for return and reuse.

[0063] The sorting unit guides damaged shot into the waste box, while qualified shot flows back to the silo through a return pipe (the inner wall is coated with a polytetrafluoroethylene friction-reducing layer, and the pipe diameter is 3-4 times the maximum shot diameter), forming a closed-loop supply.

[0064] This closed-loop design not only improves the utilization rate of the shot (single-time recovery qualification rate ≥95%), but also avoids damaged shot entering the process and affecting the shot peening effect. At the same time, the central controller monitors the qualification rate of the recovered shot in real time. When the qualification rate is lower than 90%, it automatically reduces the roller speed (each reduction amount ≤5%) or adjusts the vibration frequency to help optimize the shot peening process parameters and ensure processing stability.

[0065] The central controller receives instructions from an external CNC system or robot, and adjusts the flow parameters, vibration frequency, output channel swing angle, and roller speed in real time according to the preset shot peening intensity, coverage, and strengthening path, achieving programmed and intelligent directional shot peening. The entire process is as follows: Figure 1This invention uses a central controller (PLC / industrial computer) as its core. The process is as follows: A large number of disordered projectiles enter the silo for buffering (qualified projectiles can be recycled through a return pipe). The projectiles enter the intelligent diversion module through a conveying channel (the pipe diameter is 3-4 times the maximum particle size of the projectiles). A photoelectric counter collects the projectile flow data in real time and feeds it back to the central controller. The controller adjusts the solenoid valve according to the preset diversion parameter command (response speed ≤50ms) so that the projectiles enter the diversion channel at a flow rate matching the processing capacity of the subsequent modules. The projectiles in the diversion channel enter the spiral vibratory feeder. The central controller issues a vibration frequency command (50-200Hz) to sort the projectiles into a single uniform queue. Then, the projectiles enter the linear channel driven by the linear vibrator for further attitude calibration and feedback of sorting data (speed 1-2m / s, attitude consistency deviation ≤0.02mm). The projectiles passing through the linear channel are precisely guided to the meshing inlet of the acceleration roller group (the channel outlet and the roller meshing area are fixedly spaced 5-8mm apart, aligned with V). The guide groove center) and the central controller synchronously adjust two key parameters: first, the linear channel is controlled to swing horizontally within a range of ±15° by the linear channel angle adjustment unit (flexible coupling + rotary damping hinge structure (conventional connector)); second, the speed of the acceleration roller group is controlled by the roller speed control drive unit (2000-3000r / min). The dual control works together to control the trajectory direction and velocity of the projectile. The projectile accelerated by the acceleration roller group (final velocity 50-100m / s) forms a single-row ordered projectile flow. In basic scenarios, it is directly output as a projectile flow. In complex scenarios (deep cavity, large angle, complex curved surface reinforcement), a quick-release flexible sleeve assembly can be added.

[0066] After the sleeve assembly is added, the straight channel still has the swing function: when the sleeve is adapted to a workpiece with a complex curved surface, the channel swing can compensate for the angle deviation after the sleeve is bent, ensuring that the shot flow is always perpendicular to the workpiece surface; at the same time, the swing function can adapt to sleeves with different bending angles, improving the adaptability of the device to a variety of workpieces. The two functions complement each other rather than replace each other.

[0067] Finally, the velocity sensor feeds back the projectile velocity data to the central controller in real time, achieving closed-loop control throughout the entire process.

[0068] Experimental Example 1: Precision Strengthening of the Tenon and Groove Joint of Aero-engine Turbine Blades The tenon joint of high-pressure turbine blades in aero-engines is subjected to extremely high cyclic loads, and its fatigue performance directly affects the overall lifespan of the engine. Traditional shot peening technology cannot meet the stringent requirements for the precision and consistency of the strengthened boundary in this area. When strengthening this area using this technology, for different processing needs, the shot peening device is first integrated into the end of a six-degree-of-freedom robotic arm. A quick-release flexible sleeve assembly is selectively added after the S4 linear channel. The sleeve is made of elastic alloy material and has a built-in micro-adjustment component that allows the sleeve end to bend in any direction. Subsequently, a laser tracker is used to calibrate the tool coordinate system of the entire "robotic arm-shot peening device-flexible sleeve" to ensure a positioning accuracy better than 0.05mm.

[0069] To address the complex three-dimensional geometric features of the tenon groove, the offline programming system generates the contouring motion trajectory based on the blade CAD model while simultaneously incorporating the bending adaptation characteristics of the sleeve: the straight channel can oscillate slightly around the outlet of the spiral vibratory feeder, and the sleeve adjusts its end angle in real time according to the curvature of the tenon groove surface, ensuring that the sleeve outlet always conforms to the contour of the tenon groove surface, thus guaranteeing that the shot peening stream is always perpendicular to the tenon groove surface. 0.4mm diameter ceramic shot was selected, and the optimal parameter combination was determined through process experiments: to form a residual compressive stress layer of -750MPa on the nickel-based superalloy surface, the acceleration roller speed was set to 3000 revolutions per minute, corresponding to a shot ejection velocity of 75m / s; simultaneously, the vibration sequencer frequency was set to 1500 times per second to ensure impact coverage per unit area.

[0070] During implementation, the control system monitors the robotic arm's pose, roller speed, projectile supply status, and the oscillation status of the linear channel in real time based on the bending angle of the corresponding sleeve. Integrated force-torque sensors provide feedback to adjust injection parameters and determine the sleeve's fit status in real time. The enhanced test results show that a uniform compressive stress layer with a depth of 0.15 mm has been formed in the tenon joint, the boundary transition zone is controlled within 0.1 mm, and the surface roughness Ra value remains below 0.8 μm, fully meeting the requirements of aero-engine manufacturing specifications.

[0071] Experimental Example 2: Multifunctional Patterning Modification of Medical Device Surfaces In the field of medical implants, it is often necessary to achieve differentiated modifications in specific areas of titanium alloy surfaces to improve hydrophilicity, wear resistance, and biocompatibility. Based on this technology, a dedicated system for surface patterning of spinal implants has been developed. This embodiment employs a multi-channel shot peening device, with a quick-release, flexible sleeve assembly attached to the end of each channel. The sleeve can be selected with a preset bending angle according to the surface morphology of different functional areas and possesses aseptic fitting characteristics. Each channel can be independently controlled and loaded with shot of different materials (including stainless steel shot, glass shot, and zirconia ceramic shot).

[0072] First, functional zoning data of the implant surface is obtained through medical image processing, generating corresponding patterned reinforcement path codes and matching sleeves with appropriate bending angles for the corresponding channels. For areas requiring enhanced osseointegration, 0.1mm diameter hydroxyapatite-coated ceramic pellets are used for impact treatment at a frequency of 800 times per second, improving bioactivity through surface nano-sizing. For joint sliding areas requiring improved wear resistance, sleeves adapted to the curved surface of the sliding surface are used, with 0.2mm diameter zirconia ceramic pellets generated with sufficient impact energy at a roller speed of 2500 revolutions per minute to form a wear-resistant reinforcement layer.

[0073] It is particularly noteworthy that this process was conducted in a cleanroom environment equipped with a real-time particle monitoring system, and all additional sleeves were sterilized. Aseptic procedures were followed during replacement to ensure a contamination-free process. Post-processing characterization was performed using white light interferometry and electron backscatter diffraction techniques. The results showed that the predetermined surface property gradient distribution was successfully achieved in different functional areas, with clear transition boundaries, fully meeting the multifunctional surface engineering requirements for medical devices.

Claims

1. A mechanically controlled quantitative shot peening device, characterized in that, It includes a hopper, the outlet of which is connected to at least two diversion channels. An intelligent diversion module is installed at the connection between the outlet of the hopper and the diversion channels. The intelligent diversion module is equipped with a photoelectric counter to collect projectile flow data in real time. The diversion channel is connected to the spiral vibrating plate, which is used to form disordered projectiles into a single-row line of projectiles. The discharge port of the spiral vibratory feeder is connected to a linear channel, and an acceleration roller assembly is installed at the end of the linear channel. The acceleration roller assembly is used to accelerate the projectile through, forming an impact projectile flow.

2. The mechanically controlled quantitative shot peening device according to claim 1, characterized in that, The intelligent diversion module also includes solenoid valves, which are placed at the inlet of each diversion channel. The on / off state of the solenoid valves is adjusted to control the flow rate of the projectile into the corresponding diversion channel.

3. The mechanically controlled quantitative shot peening device according to claim 1, characterized in that, The spiral vibratory plate includes a circular base, on which a continuously rising spiral guide rail is installed, and above the guide rail is an annular barrier to prevent projectiles from splashing. Preferably, the height of the annular barrier is 2-3 times the maximum diameter of the projectile; Further preferably, the helical guide rail has an inclination angle of 15°-20° relative to the horizontal plane and inclines outward along the spiral upward direction; the helical guide rail is an open groove, and the groove depth of the guide rail is 1.2-1.5 times the maximum diameter of the projectile; the number of spiral turns of the guide rail is 3-5 turns, the minimum turning radius is 5-8 times the maximum diameter of the projectile, and the width of the guide rail groove narrows uniformly from bottom to top, with the bottom groove width being 3-4 times the maximum diameter of the projectile and the top groove width being 1.1-1.2 times the maximum diameter of the projectile.

4. The mechanical quantitative controllable shot peening device according to claim 1, characterized in that, The discharge port of the spiral vibratory feeder is connected to the linear channel by a flexible coupling, and a sealing gasket is installed at the connection.

5. The mechanical quantitative controllable shot peening device according to claim 1, characterized in that, The cross-sectional shape of the straight channel matches the shape of the projectile. The inner diameter of the straight channel is 0.05 mm larger than the diameter of the projectile, and the inner wall of the channel is polished or coated with a friction-reducing material.

6. The mechanical quantitative controllable shot peening device according to claim 2, characterized in that, The acceleration roller assembly consists of two parallel rollers. The meshing surfaces of the two rollers are machined with V-shaped annular guide grooves with a V-angle of 60°-90° and the groove walls are polished. The roller surfaces are coated with tungsten carbide, ceramic, or high wear-resistant alloy steel.

7. The mechanically controlled quantitative shot peening device according to claim 1, characterized in that, The exit of the straight channel maintains a fixed distance of 5-8mm from the acceleration roller assembly.

8. The mechanically controlled quantitative shot peening device according to claim 6, characterized in that, The mechanical quantitative controllable shot peening device also includes a flexible sleeve assembly, which includes a bending part and a connecting part. The bending part is a flexible structure of nickel-titanium shape memory alloy. The inside of the bending part is a through circular channel with the same diameter as the inner diameter of the straight channel. The inner wall is coated with a polytetrafluoroethylene anti-friction layer. The connecting part is provided with internal threads and an annular groove. Correspondingly, the outlet end of the straight channel is provided with matching external threads and elastic buckle protrusions. The outlet of the straight channel and the inlet of the bending part are respectively on both sides of the acceleration roller assembly.

9. The mechanically controlled quantitative shot peening device according to claim 8, characterized in that, The mechanical quantitative controllable shot peening device also includes a central controller, which is connected to an intelligent diversion module, a spiral vibratory feeder, a linear channel, and an acceleration roller assembly. The intelligent diversion module feeds back the real-time shot flow data to the central controller, which adjusts the solenoid valves according to preset diversion parameter commands. The central controller sends vibration frequency commands to the spiral vibratory feeder. The linear channel is equipped with an oscillation driver, and the central controller controls the oscillation of the linear channel. The central controller controls the rotation speed of the acceleration roller assembly through the roller speed control drive unit. Preferably, the mechanical quantitative controllable shot peening device further includes a recovery device, which includes an annular recovery tank, a sorting component, and a return pipe arranged around the workpiece. The width of the recovery tank is 5-8 times the maximum diameter of the shot, and the depth of the tank is 3-4 times the maximum diameter of the shot. A guide plate with an inclination angle of 30°-45° is installed on the inner side of the tank. The sorting component includes a vision inspection module to identify damage on the surface of the shot in real time and an ultrasonic inspection module to identify defects inside the shot. The sorting component sorts out qualified and undamaged shot and returns it to the hopper through the return pipe to form a closed-loop supply. The sorting component feeds back the pass rate to the central controller in real time.

10. A shot peening method using the mechanical quantitative controllable shot peening device as described in claim 9, characterized in that, The steps include the following: S1 Raw Material Feeding and Buffering At this stage, the disordered projectiles are fed into the hopper for buffering; S2 Intelligent Diversion and Flow Control The shot output from the hopper first enters the diversion area of ​​the intelligent diversion module. The photoelectric counter configured in this module collects the shot flow data in real time and feeds it back to the central controller. The central controller issues diversion parameter commands according to the preset shot peening process parameters, and adjusts the on / off state of the solenoid valve, thereby controlling the flow rate of shot into the corresponding diversion channel. S3 orderly sorting and stable transmission After being diverted, the projectiles are fed into a spiral vibratory feeder. The vibration intensity is controlled by vibration frequency commands issued by the central controller, so that as the disordered projectiles rise along the spiral guide rail, they gradually complete attitude calibration, speed pre-control, and single-line queuing, eventually forming a continuous and uniform single-line queue. Then, the single-line projectiles are fed into a linear channel driven by a linear vibrator. S4 Mechanical Roller Directional Acceleration and Output The linear channel is movably connected to the helical vibratory plate via a flexible coupling. The channel swing command issued by the central controller regulates the swing driver, so that the linear channel can swing in pitch within a range of ±15°. The projectile is stably transmitted along the axial direction in the linear channel, and its initial motion direction is adjusted synchronously with the channel swing. The orderly projectile queue is guided to the meshing inlet of the acceleration roller group. The straight channel outlet and the roller meshing area maintain a fixed distance of 5-8mm and are always aligned with the center area of ​​the V-shaped guide groove. After the projectile is obliquely injected along the axis of the straight channel, it first contacts the V-shaped groove wall of one side of the roller. The lateral constraint force provided by the groove wall guides the projectile to the center of the meshing area. At this time, the roller energizes the projectile through friction and compression. The direction of friction is superimposed on the initial motion direction of the projectile. Finally, the projectile accelerates in the initial oblique direction, and the speed increases from 1-2m / s to 50-100m / s. Meanwhile, the central controller regulates the roller speed control drive unit to keep the two rollers rotating synchronously. After the projectile enters the meshing area, it is squeezed and rubbed by the roller surface to obtain directional high-speed kinetic energy directly related to the roller linear velocity, and finally forms an ordered projectile flow with preset speed and direction. It is directly output in basic scenarios and output by adding a flexible sleeve component in complex scenarios. After output, all projectiles are collected by the recycling device. The sorting component guides damaged projectiles into the waste box, while qualified projectiles are returned to the silo through the return pipe, forming a closed-loop supply.

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