A continuous airflow guiding method for multi-layer spraying of a shock absorber housing

Abstract

The application discloses a continuous airflow guiding method for multilayer spraying of a shock absorber shell, relates to the shock absorber spraying technical field, and forms a near-wall airflow waveguide on the periphery of the shock absorber shell through a pre-charging shaping ring, a front guiding attaching ring, a rear locking attaching ring and a peripheral recycling ring, and transports and deposits paint mist drops along the near-wall airflow waveguide; after the current spraying layer is finished, a coded double pulse including a reference pulse and a check pulse is injected, the upstream sensing port and the downstream sensing port are used to read the time when a pressure wave peak arrives, the solvent absorption peak drift amount and the particle scattering envelope attenuation amount, the acceptance phase margin is calculated, and the next spraying layer is released when the permission interval and the consistency relationship are met, otherwise, a forbidden spraying control instruction and a waveguide reconstruction control instruction are output.

Description

Technical Field

[0001] This invention relates to the field of shock absorber spraying technology, specifically a continuous airflow guiding method for multi-layer spraying of shock absorber housings. Background Technology

[0002] Shock absorber housings typically require multiple coating processes, including a base coat, intermediate coat, and top coat. The workpiece is conveyed along the production line while rotating around its own axis to ensure the coating covers the cylindrical body and its connected tray roots, weld ribs, mounting lugs, and other peripheral structures. For these types of workpieces, the coating cycle time, the timing of layer switching, and the quality of coverage in irregularly shaped areas often simultaneously affect both production line efficiency and the final coating condition. Therefore, multi-layer continuous coating has always been one of the key processes in shock absorber manufacturing.

[0003] In existing technologies, one type of solution focuses on using a rotary conveyor mechanism in conjunction with a spray gun for reciprocating spraying. Layer deposition is achieved by adjusting the spray gun angle, workpiece rotation speed, and conveyor speed. The advantage of this type of solution is its intuitive equipment configuration and ease of integration into conventional spraying production lines. However, its layer switching typically relies on fixed cycle times, experienced waiting times, or simply set process formulas. When environmental temperature, humidity, wind disturbances, or local geometric differences in the workpiece change, the same waiting time does not necessarily correspond to the same layer-by-layer state. This can easily lead to situations where a localized area is still damp while the next layer has already started, or where the workpiece is ready to continue spraying but remains passively waiting.

[0004] Another approach involves introducing hot air, a guide flow, or a flash evaporation section into the spraying zone, hoping to accelerate solvent evaporation and shorten interlayer waiting time through external airflow. This method can improve continuous production cycle time to some extent, but the external airflow is often primarily geared towards overall dispersion or drying, and may not be consistent with the wall-mounted transport process on the shock absorber housing surface. In situations where the cylindrical body and irregularly shaped outer perimeter alternate, localized airflow can easily detach from the wall, rewind, or form unstable flows in shaded areas, causing the droplet deposition path and the layer tail condition determination path to separate, making it difficult to reliably identify the true adhesion state during continuous spraying.

[0005] Some solutions attempt to use solvent concentration, humidity, or local sensor signals to detect the spraying status and help determine whether to proceed to the next process. These solutions have some reference value in single-station detection scenarios, but in continuous rotary spraying, a single sensor reading is easily affected by paint mist distribution, external airflow disturbances, local geometric obstructions, and changes in the recovery status. Especially when there are geometric abrupt changes on the shock absorber housing surface, such as at the root of the spring tray, weld ribs, and mounting ears, single-point detection results can hardly simultaneously reflect the wall-attached transport status, evaporation convergence status, and the constrained status of oversprayed particles, thus limiting their accuracy in guiding interlayer switching.

[0006] Furthermore, existing improvements surrounding adhering airflow or guide nozzles mostly focus on increasing droplet adhesion, reducing scattering, or improving single-layer coverage. These improvements typically prioritize the spraying action itself, paying less attention to layer tail condition assessment, next-layer release logic, and abnormal write-back control. Consequently, even if certain guide structures can improve local wall-attachment transport in a short time, a corresponding assessment mechanism is still lacking to determine whether the current sprayed layer has reached a state ready to receive the next layer, making it difficult to support stable cycle control in multi-layer continuous spraying.

[0007] For workpieces like shock absorber housings, which combine rotating outer peripheries with locally irregular structures, a practical problem exists: the impact of different outer periphery corner positions on airflow paths and droplet transport is inconsistent. Applying a uniform airflow, negative pressure, or supplementary spray strategy to the entire outer periphery often results in overly strong control of the main cylindrical area and insufficient control of the irregularly shaped area, or situations where the irregularly shaped area is just being supplemented while other areas are subjected to additional disturbances. While existing technologies can alleviate this problem by adjusting the spray gun posture or overall parameters empirically, a method is lacking that can integrate the differences in outer periphery corner positions, wall-mounted airflow deflection, and localized recovery constraints into a continuous control chain.

[0008] Therefore, there is an urgent need for a continuous airflow guidance method for multi-layer spraying of shock absorber housings, which enables the near-wall transport of paint droplets, layer tail status judgment, release of the next layer, and abnormal write-back to be based on the same continuous physical boundary and the same control aperture, and can take into account the multi-layer switching requirements and the local stability under irregular peripheral conditions. Summary of the Invention

[0009] The purpose of this invention is to overcome the shortcomings of the prior art and propose a continuous airflow guiding method for multi-layer spraying of shock absorber housings to solve the above-mentioned problems.

[0010] The objective of this invention is achieved through the following technical solution: a continuous airflow guiding method for multi-layer spraying of shock absorber housings, comprising: conveying and driving the shock absorber housing to rotate around its own axis; establishing a basic annular flow field on the outer periphery of the shock absorber housing using a pre-charge shaping ring, and outputting a tangential thin-layer airflow to the surface of the shock absorber housing using a first slit nozzle set with a leading attachment ring; locking the tangential thin-layer airflow a second time using a second slit nozzle set with a rear locking attachment ring; forming a recovery pressure enclosure outside the tangential thin-layer airflow using a partitioned negative pressure window set with an outer recovery ring, thereby forming a near-wall airflow waveguide on the outer periphery of the shock absorber housing; sending paint droplets into the near-wall airflow waveguide in a tangentially biased manner and transporting and depositing them along the surface of the shock absorber housing; after the current spraying layer is completed, injecting a coded dual pulse including a reference pulse and a verification pulse into the near-wall airflow waveguide using a phase interpretation ring, and utilizing the upstream transmission set with a corresponding tail-end referencing ring. The sensor port and downstream sensor port read the arrival time of the pressure peak, the drift of the solvent absorption peak, and the attenuation of the particle scattering envelope corresponding to the coded double pulse. The phase margin is calculated based on the propagation time difference, solvent absorption peak drift, and particle scattering envelope attenuation corresponding to the arrival time of the pressure peak. The next spray gun opening command is released when the phase margin corresponding to two consecutive sets of coded double pulses enters the permitted range for the current sprayed layer, the propagation time difference corresponding to the arrival time of the pressure peak enters the stable range, the solvent absorption peak drift enters the convergence range, and the particle scattering envelope attenuation enters the constraint range. When the propagation time difference, solvent absorption peak drift, and particle scattering envelope attenuation corresponding to the arrival time of the pressure peak do not meet the consistency relationship, the spray gun outputs a no-spray control command and a waveguide reconstruction control command to the lead attachment ring, the rear locking attachment ring, the outer recovery ring, and the spray gun using the tail-end referee ring.

[0011] The pre-charged shaping ring injects coded double pulses into the basic annular flow field in an unpainted state, and establishes a basic propagation spectrum based on the propagation time difference, solvent absorption peak drift, and particle scattering envelope attenuation calculated from the arrival time of the corresponding pressure wave peak.

[0012] The basic propagation spectrum includes the correspondence between the shock absorber housing rotation speed, the outer peripheral characteristic angle position and the near-wall airflow waveguide deflection, and the correspondence constitutes the angular position deflection diagram.

[0013] The leading attachment ring is provided with a first slit nozzle arranged in segments along the circumference, and the rear locking attachment ring is provided with a second slit nozzle arranged in segments along the circumference. The first slit nozzle and the second slit nozzle are staggered in the axial direction and arranged with phase delay in the circumferential direction.

[0014] The outer recovery ring is equipped with partitioned negative pressure windows that rotate in the opposite direction to the near-wall airflow waveguide. The partitioned negative pressure windows form a phase-following recovery pressure enclosure around the near-wall airflow waveguide.

[0015] The encoded dual pulse includes a reference pulse and a verification pulse. The tail-end referee ring reads the arrival time of the pressure wave peak, the amount of solvent absorption peak drift, and the amount of particle scattering envelope attenuation corresponding to the reference pulse and the verification pulse through the upstream and downstream sensing ports, respectively.

[0016] The phase margin is determined by the propagation time difference corresponding to the arrival time of the pressure wave peak, the amount of solvent absorption peak drift, and the amount of particle scattering envelope attenuation. The permissible range is set separately according to the number of spraying layers.

[0017] The consistency relationship includes: when the propagation time difference corresponding to the arrival time of the pressure wave peak enters the stable range, the solvent absorption peak drift also enters the convergence range, and the particle scattering envelope attenuation also enters the constraint range.

[0018] When the consistency relationship is not established, the tail end referee ring outputs a no-spray control command and outputs at least one of the following commands: leading attachment ring momentum adjustment command, peripheral recovery ring negative pressure adjustment command, and sector backflush command.

[0019] When the spring tray root, weld rib and mounting ear plate enter the corner position corresponding to the corner position deflection diagram, adjust the duty cycle of the corresponding sector of the front guide attachment ring and the rear locking attachment ring according to the corner position deflection diagram, and simultaneously tighten the negative pressure window of the corresponding partition of the outer recovery ring.

[0020] The beneficial effects of this invention are: This invention arranges a pre-filled shaping ring, a leading attachment ring, a rear locking attachment ring, and an outer recovery ring around the outer periphery of the shock absorber housing, forming a near-wall airflow waveguide in the near-wall region that can both support the transport of paint droplets and the propagation of interpretation disturbances. Compared to conventional spraying methods that rely solely on the spray gun's posture and workpiece rotation for coverage, this structure does not directly send droplets into the free diffusion space. Instead, it first confines the droplets within the wall-attached flow zone before transporting and depositing them along the housing surface. This reduces the impact of workshop disturbances, localized wall detachment, and secondary droplet rewinding on continuous interlayer spraying. Because the outer recovery ring simultaneously forms a recovery pressure enclosure outside the waveguide, the movement boundaries of undeposited particles and diagnostic particles are stably defined, allowing the spraying transport chain and the subsequent interpretation chain to share the same physical carrier. This improves stability and repeatability under continuous spraying conditions.

[0021] This invention configures the first and second slit nozzles as a double-layer slit structure arranged in circumferential segments, offset axially, and with a phase delay in the circumferential direction. In existing shock absorber shell coating, single-layer guide flow often only establishes short-range wall-hugging flow locally, with limited ability to withstand disturbances at locations such as weld ribs and tray roots. Once there is an abrupt change in the outer contour of the shell, the guide path is prone to premature loosening. This invention establishes an initial wall-hugging swirling zone through the first slit nozzle, and then locks this swirling zone a second time through the second slit nozzle. This allows the near-wall airflow waveguide to form earlier and maintain a longer stable propagation path along the outer perimeter of the shell. In this way, the coating transport, layer tail interpretation, and local compensation are all established on a more consistent flow field boundary, which is beneficial for improving the coverage integrity and control accuracy under irregular outer perimeter conditions.

[0022] This invention injects a coded dual pulse, including a reference pulse and a verification pulse, into the near-wall airflow waveguide after the current coating layer is completed. The upstream and downstream sensing ports are used to read the corresponding pressure peak arrival time, solvent absorption peak drift, and particle scattering envelope attenuation, respectively. Compared to methods that determine interlayer switching timing based on fixed flash-drying time or a single concentration signal, this invention uses the reference pulse to obtain the main propagation state and the verification pulse to confirm whether the attenuation and broadening along the same path remain consistent. A unified interpretation caliber is then formed by sampling from both upstream and downstream positions. Since the propagation time difference reflects the overall propagation state of the near-wall waveguide, the solvent absorption peak drift reflects the evaporation and convergence of the current coating layer, and the particle scattering envelope attenuation reflects the degree of particle confinement by the outer recovery ring, these three quantities can characterize the same interlayer transfer state from different perspectives, thus reducing the release risk caused by misjudgment of a single signal.

[0023] This invention further calculates the bearing phase margin based on the propagation time difference, solvent absorption peak drift, and particle scattering envelope attenuation. Only when the bearing phase margin enters the permissible range, the propagation time difference enters the stable range, the solvent absorption peak drift enters the convergence range, and the particle scattering envelope attenuation enters the constraint range, is the permissible release ring releasing the spray gun activation command for the next coating layer. Compared to control methods that only consider whether a single threshold is triggered, this gating relationship requires multiple state variables to simultaneously satisfy consistency within the same cycle, thus distinguishing between layers that already meet the interlayer bearing conditions and those with local instability. Especially in scenarios where continuous conveying, continuous rotation, and continuous spraying of the shock absorber housing occur in parallel, the above criteria ensure that the activation time of the next layer corresponds to the actual convergence state of the current workpiece, rather than being simply bound to a fixed cycle time, which is beneficial for improving the reliability of interlayer switching and surface quality consistency.

[0024] This invention sets different permissible intervals according to the spraying layer, so that different stability intervals, convergence intervals, constraint intervals, and bearing phase margin permissible intervals are used after the bottom layer spraying, the middle layer spraying, and the top layer spraying. Existing continuous spraying processes often set the switching conditions between each layer uniformly, easily ignoring the differences in the volatile state, surface shear sensitivity, and particle constraint requirements of different sprayed layers. This invention calls different permissible intervals through spraying layer indexing, so that the bottom layer focuses more on overall bearing capacity, the middle layer focuses more on spreading stability, and the top layer focuses more on constraint smoothness and perturbation sensitivity. As a result, the same set of equipment can be adapted to different convergence targets of multi-layer spraying without changing the core mechanism, which is beneficial to improving the adaptability and process calibration efficiency of continuous processes.

[0025] When the consistency relationship is not established, this invention outputs a no-spray control command and a waveguide reconstruction control command to the leading attachment ring, the rear locking attachment ring, the outer recovery ring, and the spray gun via the tail-end referee ring. Furthermore, the tail-end referee ring outputs at least one of the following commands simultaneously: a momentum adjustment command for the leading attachment ring, a negative pressure adjustment command for the outer recovery ring, and a sector backflush command. Compared to methods that only prompt manual intervention or simple delays after an anomaly is detected, this invention directly writes the anomaly judgment result back to the airflow waveguide formation stage and the spraying execution stage. This allows anomaly handling to move beyond the monitoring layer and instantly change the waveguide boundary, recovery pressure enclosure, and spray gun state. This enables targeted contraction actions in different anomaly scenarios such as overall over-wetting, localized recovery pressure enclosure leakage, and spray gun atomization drift. It also helps to limit the impact of anomalies to the current cycle or current sector, improving the system's maintainability and continuous operation capability.

[0026] This invention also establishes a basic propagation map in an unpainted state and generates an angular position deflection map based on the correspondence between the shock absorber housing rotation speed, the outer peripheral characteristic angular position, and the near-wall airflow waveguide deflection. For irregularly shaped areas such as the spring tray root, weld ribs, and mounting lugs, conventional methods typically rely on overall airflow enhancement, overall pressurization, or empirical supplementary spraying, which can easily amplify disturbances in non-target areas. This invention adjusts the duty cycle of the corresponding sectors of the leading and trailing attachment rings based on the angular position deflection map, and simultaneously tightens the negative pressure window of the corresponding partition of the outer recovery ring, so that the compensation action is locally carried out around the sector where the current outer peripheral characteristic is located. Since the compensation amount comes from the correspondence between the basic propagation map and the current sector, the compensation does not occur independently of the interpretation chain, but is still subject to the phase margin and consistency relationship gating, thus balancing the coverage requirements of irregularly shaped areas and the overall waveguide stability. Attached Figure Description

[0027] Figure 1 The process of this invention Figure 1 ; Figure 2The process of this invention Figure 2 ; Figure 3 The process of this invention Figure 3 . Detailed Implementation

[0028] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Example 1 like Figure 1 As shown, this embodiment focuses on a continuous multi-layer spraying production line for shock absorber housings. The shock absorber housing is clamped by an upstream conveying and clamping mechanism and enters the spraying area axially. After entering the spraying area, it is continuously rotated around its own axis by a rotary drive mechanism. In this embodiment, the outer diameter of the shock absorber housing is 52mm, the effective spraying length is 360mm, the conveying speed is 0.10m / s, and the rotation speed is 220rpm. Along the movement direction of the shock absorber housing, the spraying area is sequentially arranged with a pre-charge shaping ring, a leading attachment ring, a rear locking attachment ring, an outer recovery ring, a phase judgment ring, a permission release ring, and a tail end judging ring. The axial distance between the pre-charge shaping ring and the leading attachment ring is 18mm, the axial distance between the leading attachment ring and the rear locking attachment ring is 12mm, the axial distance between the rear locking attachment ring and the outer recovery ring is 10mm, the phase judgment ring is located 20mm downstream of the outer recovery ring, the permission release ring is located 35mm downstream of the phase judgment ring, and the tail end judgment ring is located 28mm downstream of the permission release ring. The annular gap between the leading attachment ring and the outer surface of the shock absorber housing is 3.2mm, the annular gap between the rear locking attachment ring and the outer surface of the shock absorber housing is 3.0mm, and the minimum gap between the outer edge of the partition negative pressure window of the outer recovery ring and the outer surface of the shock absorber housing is 5.0mm.

[0030] The leading attachment ring has twelve sets of first slit nozzles evenly distributed circumferentially. Each set of first slit nozzles has a width of 0.8 mm and its ejection direction is deflected by 28° relative to the tangential direction of the shock absorber housing. Its function is to organize the compressed air into a thin tangential airflow that adheres to the outer surface of the shock absorber housing. The rear locking attachment ring has twelve sets of second slit nozzles correspondingly arranged circumferentially. Each set of second slit nozzles has a width of 0.6 mm. Each second slit nozzle is offset 12 mm axially from the corresponding first slit nozzle and delayed 15° circumferentially. This is used to lock the thin tangential airflow a second time, forming a continuous near-wall airflow waveguide on the outer periphery of the shock absorber housing. The outer recovery ring is equipped with twelve partitioned negative pressure windows, each with a central angle of 18°. A 12° isolation zone is reserved between adjacent partitioned negative pressure windows. The outer recovery ring provides a reference negative pressure of -1.4 kPa during operation, which can be adjusted within the range of -1.0 kPa to -1.8 kPa if necessary, thereby forming a recovery pressure enclosure outside the near-wall airflow waveguide. The spray gun is positioned outside the narrow band area between the leading attachment ring and the outer recovery ring. The angle between the spray gun's spray direction and the tangential direction of the shock absorber housing is 22°, allowing the paint droplets to first enter the near-wall airflow waveguide and then be transported and deposited along the outer surface of the shock absorber housing.

[0031] A pulse nozzle group is set within the phase interpretation loop. After the current coating layer is completed, the pulse nozzle group sequentially injects a reference pulse and a verification pulse into the near-wall airflow waveguide. In this embodiment, while emitting the reference pulse and verification pulse, the pulse nozzle group coaxially delivers quantitative calibration solvent particles and diagnostic particle particles to form repeatable solvent absorption peaks and particle scattering envelopes even when the spray gun is closed or there is no paint. The quantitative calibration solvent particles are tracer solvent vapors compatible with the current coating system, with a single injection volume fraction of 0.08% to 0.12%. The diagnostic particle particles are inert scattering particles that do not participate in film formation, with a particle size of 0.8 μm to 1.5 μm and a single injection concentration of 0.6 mg / L to 1.0 mg / L. The duration of the reference pulse is 6 ms, the duration of the verification pulse is 4 ms, the interval between the two is 12 ms, and the interval between two adjacent sets of coded double pulses is 0.8 s. The tail-end referee ring is equipped with upstream and downstream sensor ports. The upstream sensor port is located 12mm downstream of the phase interpretation ring, and the downstream sensor port is located at the axial center of the tail-end referee ring. Both the upstream and downstream sensor ports integrate pressure sampling units, solvent absorption sampling units, and particle scattering sampling units. The pressure sampling frequency is 2kHz, the solvent absorption sampling frequency is 500Hz, and the particle scattering sampling frequency is 500Hz. The controller aligns the three types of sampled data according to the same timestamp and forms pressure peaks, solvent absorption peaks corresponding to quantitative calibration solvent particles, and particle scattering envelopes corresponding to diagnostic particle particles using the corresponding sampling windows of the reference pulse and calibration pulse, respectively.

[0032] The following describes the working process. After the shock absorber housing enters the spraying area, the pre-charge shaping ring first outputs a basic annular airflow of 3.5 m / s for 0.6 s to establish the basic annular flow field. The leading attachment ring then outputs a tangential thin-layer airflow of 5.2 m / s, and the rear locking attachment ring outputs a locking airflow of 4.6 m / s. The outer recovery ring simultaneously establishes a reference negative pressure, and the three together form a near-wall airflow waveguide. When the bottom layer spraying begins, the spray gun delivers the bottom layer coating into the near-wall airflow waveguide with an atomization pressure of 0.18 MPa. The coating droplets form a spiral wall-attached transport path along the surface of the shock absorber housing, and undeposited particles are drawn into the recovery pressure enclosure by the outer recovery ring. After the base coat is applied, the spray gun is closed while the near-wall airflow waveguide remains continuous. The pulse nozzle group emits the first set of coded double pulses, and the upstream and downstream sensors begin sampling. The controller calculates the propagation time difference, solvent absorption peak drift, particle scattering envelope attenuation, and phase margin sequentially based on the same set of sampled data. If the result of this set does not enter the permissible range, the permissible release loop continues to maintain the spray-off state, the near-wall airflow waveguide maintains a low-shear flow state, and waits for the next set of coded double pulses. If two consecutive sets of results enter the permissible range, the permissible release loop outputs a command to open the intermediate layer spray gun and writes the current phase margin into the current cycle's recording area as a reference value for the next cycle. The working process of the intermediate and top coats is the same as the interpretation process after the base coat is applied, except that the permissible range and negative pressure adjustment boundary switch with each coat.

[0033] In this embodiment, the propagation time difference, solvent absorption peak shift, particle scattering envelope attenuation, and receiving phase margin are determined as follows. For the first... The pressure wave peak times of the group-coded dual pulse, the reference pulse, and the calibration pulse at the upstream sensing port are respectively denoted as: and The pressure peak times corresponding to the downstream sensor ports are recorded as follows: and The propagation time difference is defined as follows: in, Indicates the first The mean propagation time difference of group-coded dual pulses in near-wall airflow waveguides. , This indicates the peak times of the reference pulse and the calibration pulse at the upstream sensor port. , This indicates the peak times of the reference pulse and the calibration pulse at the downstream sensing port. Using the average value of the two types of pulses is to reduce the impact of local transient disturbances on the single propagation time.

[0034] Suppose the upstream sensor port is connected to the first The average solvent absorption peak of the quantitative calibration solvent microparticles in the group-coded double pulse is Downstream sensor port to the first The average solvent absorption peak of the quantitative calibration solvent microparticles in the group-coded double pulse is The reference absorption peak obtained by sampling from the pre-charged shaping ring under the same injection volume condition in the no-load state is: The solvent absorption peak shift is defined as in, Indicates the first The amount of shift of the solvent absorption peak corresponding to the group-coded double pulse relative to the unloaded state. The average value of five consecutive samples of coded double pulses is determined when the device enters the spraying area from the shock absorber housing without being painted, under the same quantitative calibration solvent microparticle injection volume. In this embodiment, if the standard deviation of the absorption peak obtained by sampling under no-load conditions is greater than 3% of the reference mean, the controller first prohibits entry into the spraying stage and re-executes the pre-charge shaping.

[0035] Suppose the upstream sensor port is connected to the first The peak value of the particle scattering envelope of diagnostic particle clusters in the group-coded dual pulse is Downstream sensor port to the first The peak value of the particle scattering envelope of diagnostic particle clusters in the group-coded dual pulse is The particle scattering envelope attenuation is defined as in, Indicates the first The particle scattering envelope attenuation after the group-coded double pulse propagates along the near-wall airflow waveguide. The smaller the value, the weaker the binding force of the outer recycling ring on the particles; The larger the value, the more stably the particles are confined within the recycling pressure enclosure.

[0036] To ensure that the three types of quantities participate in gating decisions on the same scale, this implementation defines the receiving phase margin as... in, Indicates the first The phase margin corresponding to the group-coded double pulse. and These represent the lower and upper limits of the propagation time difference, respectively. and These represent the lower and upper limits of solvent absorption peak shift, respectively. and These represent the lower and upper limits of the particle scattering envelope attenuation, respectively. Weights of 0.40, 0.35, and 0.25 correspond to the contribution weights of the propagation time difference, solvent absorption peak shift, and particle scattering envelope attenuation, respectively, and their sum is 1. In this embodiment, the default interval after the bottom layer is taken as... , , , , , The default range after the intermediate layer ends is taken as follows: , , , , , The default range after the surface layer is completed is taken as follows: , , , , , The above values ​​are written to the controller as the engineering default value, and can be updated according to the calibration batch data after 20 consecutive workpieces are run.

[0037] The release criterion for the permission release loop is defined as follows: in, Indicates the first Release criteria corresponding to group-coded double pulses and These represent the lower and upper limits of the allowable phase margin, respectively. In this embodiment, after the bottom layer is completed... Take 0.72, Take 0.88; after the intermediate layer is completed. Take 0.75, Take 0.90; after the surface layer is completed Take 0.78, Take 0.92. Only when... and Only then will the release ring output the spray gun activation command for the next coating layer. If If so, the release ring is allowed to maintain the no-spray state and send the current data to the end referee ring.

[0038] The leading and trailing attachment rings are not simply connected in series for air supply. Instead, a tangential thin-layer airflow is first established on the outer surface of the shock absorber housing, and then the phase-delayed second slit nozzle locks this tangential thin-layer airflow in a stable near-wall region, allowing the spray droplets, coded dual pulses, and diagnostic particles to propagate within the same physical carrier. The outer recovery ring's recovery pressure isolates large-scale external turbulence from the near-wall airflow waveguide, ensuring that the changes collected by the upstream and downstream sensors primarily reflect the coating state itself, rather than fluctuations in the workshop environment. The reference pulse reflects the average propagation state of the current near-wall airflow waveguide, while the calibration pulse reflects the attenuation and broadening characteristics along the same path; both are used in the calculation of the propagation time difference. The solvent absorption peak drift reflects the degree to which the current coating alters the local volatile environment, and the particle scattering envelope attenuation reflects the degree to which the outer recovery ring confines oversprayed particles. When all three quantities enter the corresponding range simultaneously, it means that the current coating layer has met the conditions for receiving subsequent coating layers. When any of the three quantities deviates from the corresponding range, it means that there are still unstable factors in the current near-wall airflow waveguide, the current volatilization state, or the current recovery pressure. If spraying continues at this time, the quality of subsequent coating layer overlay will be unstable. Therefore, spraying must be prohibited by the permission release ring.

[0039] In one embodiment, the controller acquires the first set of coded double pulses after the base coat has been applied. , , Substituting into the above formula, we get Clearly, it does not fall into the permitted range after the bottom layer ends. The release ring maintains a no-spray state, the negative pressure of the outer recovery ring is increased to -1.6 kPa, and the tangential flow velocity of the leading attachment ring is reduced to 4.6 m / s. The second set of coded dual pulses was acquired. , , Calculations yielded Although the area has now entered the permitted range, the permitted release loop remains closed to spraying because the previous set of results failed. The third set of coded double pulses was acquired. , , Calculations yielded ,and Since both sets of consecutive results meet the release conditions, the permission release loop outputs the intermediate layer spray gun opening command within 20ms after the third set of judgments, and sets the current set of results accordingly. , , and Write to the record area for this cycle. If it occurs in any determination cycle... Entering a stable range Below In the case of insufficient restraint of the outer recovery ring, the tail-end referee ring determines that the outer recovery ring is not sufficiently restrained and immediately outputs a spray ban control command and a waveguide reconstruction control command. The waveguide reconstruction control command includes increasing the negative pressure of the outer recovery ring by 0.2 kPa and increasing the flow velocity of the rear locking attachment ring by 0.3 m / s for 1.2 s, waiting for the next set of coded double pulses to re-determine.

[0040] In this embodiment, the spray-stop control command and waveguide reconstruction control command are uniformly issued by the tail-end referee ring. The spray-stop control command acts directly on the spray gun, keeping it closed until an unlock signal is received. The waveguide reconstruction control command acts simultaneously on the leading attachment ring, the rear locking attachment ring, and the outer recovery ring to adjust the tangential flow rate, lock the flow rate, and recover the negative pressure. If three consecutive sets of coded double pulses fail to meet the release conditions, the controller marks the current shock absorber housing as a delayed workpiece and reduces the conveying speed to 0.07 m / s. If five consecutive sets of coded double pulses still fail to meet the release conditions, the controller terminates the current workpiece from entering the next coating layer and sends the current workpiece to the re-inspection station.

[0041] Example 2 like Figure 1 and Figure 2 As shown, this embodiment integrates unpainted calibration, irregular area compensation, and sector-based waveguide adjustment into a continuous closed loop of multi-layer spraying of the shock absorber housing. The shock absorber housing is still conveyed axially by the clamping and conveying mechanism and rotates around its own axis. Along the direction of housing movement, the spraying area is sequentially arranged with a pre-charge shaping ring, a leading attachment ring, a rear locking attachment ring, an outer recovery ring, a phase judgment ring, a permission release ring, and a tail-end referencing ring. The difference from the basic embodiment is that this embodiment adds an angular position encoder to the rotary drive shaft, adds a basic propagation spectrum recording area and an angular position deflection map recording area to the controller, and rewrites the leading attachment ring, rear locking attachment ring, and outer recovery ring into a structure that allows independent adjustment by sector. The angular position encoder divides the circuit into twenty-four sectors, with each sector having a circumferential angle width of 15°. The leading attachment ring has twenty-four sets of first slit nozzles along its circumference, the rear locking attachment ring has twenty-four sets of second slit nozzles along its circumference, and the outer recovery ring has twenty-four partitioned negative pressure windows along its circumference. The basic duty cycle of the first slit nozzle is preset to 0.62, the basic duty cycle of the second slit nozzle is preset to 0.54, and the basic negative pressure of the partitioned negative pressure windows is preset to -1.35 kPa. The slit width of each first slit nozzle is 0.7 mm, and the slit width of each second slit nozzle is 0.5 mm. The second slit nozzle is offset by 10 mm axially from the corresponding first slit nozzle and delayed by 12° circumferentially, thereby forming a near-wall airflow waveguide on the outer periphery of the shell that can be locally deflected according to the sector. The partitioned negative pressure windows correspond one-to-one with the twenty-four sectors, with a central angle of 10° for each window and a 5° isolation zone between windows, so that only the target sector and its adjacent sectors are subject to local recovery pressure correction during irregular region compensation.

[0042] In this embodiment, the basic propagation pattern is formed by the coded double-pulse learning cycle in the unpainted state. After the shock absorber housing enters the spraying area, the spray gun is not activated initially. The pre-charge shaping ring establishes the basic annular flow field, and the leading attachment ring, the rear locking attachment ring, and the outer recovery ring establish the near-wall airflow waveguide and its outer recovery pressure enclosure. To ensure repeatable solvent absorption peak drift and particle scattering envelope attenuation in the unpainted state, the phase interpretation ring simultaneously delivers quantitative calibration solvent particles and diagnostic particle particles during each set of coded double-pulse injection. The quantitative calibration solvent particles are compatible with the solvent system used in the formal spraying system, and the diagnostic particle particles are inert scattering particles that do not participate in film formation. The controller organizes the learning data according to the speed range and sector number. The speed ranges are 180 rpm, 220 rpm, and 260 rpm, and eight sets of coded double pulses are continuously acquired at each speed range. The first RPM gear and the first For each sector, the controller averages the propagation time difference, solvent absorption peak shift, and particle scattering envelope attenuation corresponding to the eight sets of coded double pulses to form a basic propagation spectrum. in, Indicates the first The first speed gear The basic propagation graph entries corresponding to each sector This indicates the number of coded double pulse groups acquired from the same sector at the same speed; in this embodiment, it is set to 8. Indicates the first The propagation time difference of the group-coded double pulse in this sector at this level. Indicates the first The amount of solvent absorption peak shift corresponding to the group-coded double pulse. Indicates the first The particle scattering envelope attenuation corresponding to the group-coded double pulse. , and These represent the baseline mean values ​​of the three types of quantities mentioned above for each sector. If any one of the eight samples in the same sector is missing, the current learning round for that sector is invalid and the no-load learning for that sector will be re-executed. If the difference between the mean values ​​of two consecutive learning rounds exceeds 5% of their respective mean values, the basic propagation map for that speed gear will not be written into the recording area, but will remain in a no-injection state and will require the no-load learning to be re-executed.

[0043] To incorporate irregular peripheral features into the same waveguide chain, this implementation further generates an angular position deflection map after establishing the basic propagation pattern. The controller first uses the average value of the sector in the main cylindrical region as the reference center for the same speed range to obtain the reference propagation time difference. Reference solvent absorption peak shift and reference particle scattering envelope attenuation Then, based on the degree of deviation of each sector from the reference center, calculate the required waveguide deflection for that sector. in, Indicates the first The first speed gear The angular deflection of each sector indicates that the near-wall airflow waveguide needs to be deflected along the leading edge of the shell, while a negative value indicates that it needs to be recovered along the trailing edge of the shell. This represents the conversion factor from the propagation time difference deviation to the angular deflection; in this embodiment, it is taken as 1.8° / ms. This represents the conversion factor from the amount of solvent absorption peak shift to the amount of angular deflection; in this embodiment, it is taken as 30°. The conversion factor representing the deviation of particle scattering envelope attenuation from angular deflection is taken as 16° in this embodiment. The sectors corresponding to the spring tray root, weld ribs, and mounting lugs are jointly identified by an angular position encoder and a preset geometric angular position table. When the aforementioned peripheral features enter the current sector, the controller reads the corresponding... This serves as the deflection base value for the characteristic sector.

[0044] After obtaining the angular position deflection, the controller synchronously generates sector compensation values ​​for the leading attachment ring, the rear locking attachment ring, and the outer recovery ring. For the first... The first speed gear For each sector, the duty cycle of the first slit nozzle, the duty cycle of the second slit nozzle, and the negative pressure correction amount of the partition negative pressure window are determined by the following formulas. in, Indicates the first The duty cycle of the first slit nozzle target in each sector Indicates the first The duty cycle of the second slit nozzle target in each sector Indicates the first The target negative pressure of the partitioned negative pressure window for each sector. This indicates that the duty cycle of the first slit nozzle base is 0.62. This indicates that the duty cycle of the second slit nozzle base is 0.54. This indicates a base negative pressure of -1.35 kPa. This represents the duty cycle adjustment coefficient for the first slit nozzle, which is taken as 0.015 / ° in this embodiment. This represents the duty cycle adjustment coefficient for the second slit nozzle, which is taken as 0.012 / ° in this embodiment. This represents the negative pressure adjustment coefficient, which is taken as 0.04 kPa / ° in this embodiment. This indicates that the calculation results are restricted to a given upper and lower limit. Therefore, each record in the angular position deflection diagram simultaneously includes the sector number, the corresponding peripheral feature, the angular position deflection amount, the duty cycle correction amount for the first slit nozzle, the duty cycle correction amount for the second slit nozzle, and the negative pressure correction amount for the partition negative pressure window, which can be called in the spraying cycle.

[0045] The following describes the working process. After the shock absorber housing completes no-load learning in an unpainted state, the controller writes the basic propagation map items corresponding to the three speed levels and twenty-four sectors into the basic propagation map recording area, and writes the angular position deflection amount generated according to the sector and its execution amount into the angular position deflection map recording area. When entering the formal painting stage, the pre-charge shaping ring outputs the basic annular flow field, and the leading attachment ring and the rear locking attachment ring first establish a standard near-wall airflow waveguide according to the basic duty cycle, and the outer recovery ring establishes the basic recovery pressure enclosure; when the angular position encoder identifies that the current housing has rotated to the spring tray root sector, the weld rib sector, or the mounting ear plate sector, the controller reads the corresponding map item according to the current speed level and performs local compensation on the target sector and one sector on each of its two adjacent sides. For the leading attachment ring, the controller switches the duty cycle of the first slit nozzle of the corresponding sector to For the rear locking ring, the controller switches the duty cycle of the second slit nozzle in the corresponding sector to... For the outer recycling loop, the controller switches the negative pressure of the corresponding sector's partition negative pressure window to... This local compensation lasts for one sector angle width and then returns to the base duty cycle and base negative pressure at a 30ms ramp after the sector crosses the boundary, in order to avoid creating new airflow waveguide breakpoints at the sector boundary.

[0046] In this embodiment, the idle learning cycle and the irregular region compensation cycle are always gated by the receiving phase margin. At the end of each spray coating, the controller still calculates the receiving phase margin based on the propagation time difference, solvent absorption peak drift, and particle scattering envelope attenuation. Only when Local compensation is only allowed to continue if it remains within the permitted range of the current layer. To determine whether the current compensation still matches the basic propagation map, the controller calculates the map mismatch index for the active sector. in, Indicates the first The mismatch index of active sectors relative to the underlying propagation map within the next interpretation period. This indicates the propagation time difference in the current interpretation period. This indicates the amount of solvent absorption peak shift during the current reading period. This indicates the particle scattering envelope attenuation during the current interpretation period. , and These represent the baseline values ​​of the graph corresponding to the current sector at the current speed setting. , and These represent the stability interval width, convergence interval width, and constraint interval width of the current coating layer, respectively. If If the current compensation matches the basic propagation map, then local compensation can be maintained; if If the reading cycle only lasts for one period, then cancel the current sector compensation, restore the basic duty cycle and basic negative pressure, and maintain the no-spray state until the next set of coded double pulses is reread; if Or satisfy for three consecutive reading cycles If a map mismatch occurs, the system will enter a recalibration and degradation mode.

[0047] After entering the recalibration degradation mode, the conveyor speed decreased from 0.10 m / s to 0.08 m / s, the rotation speed switched from the current setting to 180 rpm, the spray gun remained closed, the front guide ring and rear locking ring restored their basic duty cycle, and the outer recovery ring was uniformly raised to -1.55 kPa. Subsequently, six sets of coded dual pulses were re-acquired in a paint-free state. The controller recorded the baseline vector obtained during the recalibration period as... The basic propagation map can only be updated using the following formula if all six samples meet the mismatch index requirement of no more than 0.20. in, This represents the updated base propagation graph term. This represents the map update weight, which is set to 0.15 in this implementation. This represents the base propagation graph terms before the update. This represents the sector baseline vector obtained from recalibration. If the mismatch index of any of the six sampling groups is greater than 0.20, the basic propagation map is frozen and not updated, the current workpiece exits the continuous spraying cycle and is transferred to the re-inspection station.

[0048] In one embodiment, as the shock absorber housing rotates at 220 rpm and enters the intermediate layer spraying section along the conveying direction, the angular position encoder identifies the spring tray root entering sector 6. The unloaded learning of sector 6 at this position is then performed. ms , The reference center of the main cylindrical area of ​​the same grade is taken ms , Substituting into the formula for calculating the angular position deflection, we obtain... The controller then received , , kPa, and switch sectors 5 to 7 to the corresponding compensation value. The encoded double pulse at the end of the current layer spraying is then read. ms , Receive phase margin It falls within the middle layer permitted range, and at the same time, it is calculated that... This indicates that after compensation for the irregular region, the current active sector still matches the basic propagation map. Therefore, the local compensation remains effective, allowing the next layer of spraying to be released at the predetermined pace. If subsequent two sets of interpretations occur in the same scenario... Continued decline and If the value is increased to 0.41, the controller will first cancel the local compensation for sector 6 and maintain the no-spray policy; if the cancellation is followed by... If it remains above 0.35, it will further enter the recalibration and downgrade mode.

[0049] This implementation does not simply add an unloaded calibration step, but rather pre-incorporates the geometric influence of the irregular region into the same physical aperture of the near-wall airflow waveguide. Since the spring tray root, weld ribs, and mounting lugs all alter the local wall attachment path, local evaporation boundary, and local recovery pressure constraint, if spraying is still performed with a uniform airflow and negative pressure throughout the circumference, the sprayed coating will exhibit a split state when entering the irregular region: the waveguide remains continuous but local deposition distortion occurs, or the deposition is temporarily effective but waveguide interpretation is distorted. This implementation first records the intrinsic propagation characteristics of each sector in the unpainted state using a basic propagation spectrum, and then uses an angular position deflection diagram to convert these intrinsic differences into synchronous compensation amounts for the duty cycle of the first slit nozzle, the duty cycle of the second slit nozzle, and the negative pressure of the partitioned negative pressure window. This ensures that when the irregular region enters, the waveguide geometry and recovery boundary are altered, rather than the spray volume being directly increased or decreased. In this way, the paint droplets are still transported within the same near-wall airflow waveguide, and the coded double pulses still propagate within the same path, maintaining the same interpretation aperture for phase margin and sector compensation actions. The introduction of the spectrum mismatch index explicitly quantifies whether the current sector still belongs to the learned geometric conditions. Once the local waveguide has deviated from the basic propagation spectrum to the point that it cannot be supported by the current angular position deflection map, the system immediately cancels compensation, stops spraying, and recalibrates to avoid continuing to run along the mismatch spectrum.

[0050] Example 3 like Figures 1 to 3As shown, this embodiment unifies the division of labor in interpreting the coded double pulse, setting the permissible interval corresponding to the coating layer, determining consistency, and controlling multi-branch write-back into a high-level application closed loop. The shock absorber housing is still conveyed axially by the clamping and conveying mechanism and rotates around its own axis. The coating area is arranged sequentially along the direction of housing movement: pre-charge shaping ring, leading attachment ring, rear locking attachment ring, outer recovery ring, phase interpretation ring, permissible release ring, and tail-end referee ring. The leading attachment ring, rear locking attachment ring, and outer recovery ring together form a near-wall airflow waveguide. The angular position encoder still outputs the current peripheral characteristic angular position according to twenty-four sectors. The controller still retains the basic propagation spectrum recording area and the angular position deflection map recording area. The difference from the previous embodiment is that this embodiment writes the coating layer, coded double pulse data frame, consistency determination result, and the spray prohibition control command and additional adjustment command output by the tail-end referee ring when the consistency relationship is not established into the same periodic recording area, and is executed sequentially by the permissible release ring and the tail-end referee ring. The coating layer index is denoted as ,in The corresponding reading cycle after the completion of the base coat spraying. The corresponding reading cycle after the intermediate layer spraying is completed. The corresponding reading cycle after the topcoat spraying is completed. The controller presets permissible range parameters for each of the three spraying layers, with the stable range after the bottom coat spraying being [value missing]. Convergence interval Constraint interval selection Accepting the allowable range of phase margin The stable range after the intermediate layer spraying is completed is taken as follows: Convergence interval Constraint interval selection Accepting the allowable range of phase margin The stable range after the topcoat spraying is completed is taken as follows: Convergence interval Constraint interval selection Accepting the allowable range of phase margin The above parameters are written into the controller as engineering default values. When twenty workpieces are run continuously and no pattern mismatch is triggered in any cycle, updates are allowed according to the calibration batch data.

[0051] In this embodiment, the phase interpretation ring injects a set of coded double pulses into the near-wall airflow waveguide after each spray coating is completed. The coded double pulses include a reference pulse and a verification pulse. The reference pulse is used to determine the main propagation time of the current near-wall airflow waveguide; the verification pulse is used to confirm the broadening, attenuation, and constraint states in the same path. To maintain the continuity of the interpretation chain in the spray gun closed and paint-free states, the phase interpretation ring simultaneously injects quantitative calibration solvent particles and diagnostic particle particles when injecting the reference pulse and verification pulse. The quantitative calibration solvent particles are used to form a stable solvent absorption peak, and the diagnostic particle particles are used to form a stable particle scattering envelope. The duration of the reference pulse is 6 ms, the duration of the verification pulse is 4 ms, the interval between the two is 12 ms, and the interpretation interval between two adjacent sets of coded double pulses is 0.8 s. The upstream sensor port is located 8 mm downstream of the phase interpretation ring, and the downstream sensor port is located at the axial center of the tail-end interpretation ring. Both integrate pressure sampling units, solvent absorption sampling units, and particle scattering sampling units. The pressure sampling frequency is 2 kHz, the solvent absorption sampling frequency is 500 Hz, and the particle scattering sampling frequency is 500 Hz. The controller assembles the hierarchical index, sector number, upstream sampling result, and downstream sampling result corresponding to the same set of coded double pulses into a unified data frame. in, Indicates the number of coating layers. The interpretation cycle number is The active sector is Unified data frame, and These represent the arrival times of the pressure wave peaks at the upstream sensor port relative to the reference pulse and the calibration pulse, respectively. and These represent the arrival times of the pressure wave peaks at the downstream sensing port in response to the reference pulse and the calibration pulse, respectively. and These represent the solvent absorption peak values ​​at the upstream sensing port for the reference pulse and the calibration pulse, respectively. and These represent the solvent absorption peak values ​​at the downstream sensing port in response to the reference pulse and the calibration pulse, respectively. and These represent the peak values ​​of the particle scattering envelopes at the upstream sensor port for the reference pulse and the calibration pulse, respectively. and These represent the peak values ​​of the particle scattering envelopes at the downstream sensor port to the reference pulse and the calibration pulse, respectively. If any field in the unified data frame is missing, the period is directly recorded as a no-spray period and does not enter the permission release loop.

[0052] The controller first generates three types of characteristic quantities from the raw quantities in the unified data frame. The propagation times corresponding to the reference pulse and the check pulse are denoted as follows: and Then, based on this, the propagation time difference can be obtained. in, Indicates the first The average propagation time difference of the coded double pulse in the near-wall airflow waveguide within each interpretation cycle. Indicates the propagation time of the reference pulse. This indicates the propagation time of the calibration pulse. The controller then averages the solvent absorption peaks of the reference pulse and the calibration pulse, and normalizes them relative to the baseline propagation spectrum of the same sector under unpainted conditions to obtain the solvent absorption peak shift. in, Indicates the first The amount of solvent absorption peak shift per reading cycle Indicates the current RPM gear. Current sector The baseline absorption value without paint is formed by quantitatively calibrated solvent particles in the basic propagation spectrum. The controller then generates the particle scattering envelope attenuation based on the particle scattering envelope peak values ​​corresponding to the upstream and downstream diagnostic particle particles. in, Indicates the first The particle scattering envelope attenuation amount for each reading cycle. Once generated, the above three types of characteristic quantities are written into the current cycle recording area and used for consistency relationship determination.

[0053] In this embodiment, the phase margin is still determined jointly based on the propagation time difference, solvent absorption peak shift, and particle scattering envelope attenuation, but the corresponding allowable range is read separately for different spraying layers. For each spraying layer... The In each reading cycle, the controller reads from the permission range parameter table. , , , , , , and And calculate the phase margin accordingly. in, Indicates the number of coating layers In the Phase margin for each reading cycle and These represent the number of coating layers. The lower and upper limits of the stable range, and These represent the number of coating layers. The lower and upper bounds of the convergence interval, and These represent the number of coating layers. The lower and upper limits of the constraint interval are defined. Weights of 0.40, 0.35, and 0.25 correspond to the contribution weights of propagation time difference, solvent absorption peak drift, and particle scattering envelope attenuation, respectively, all of which are non-negative and sum to 1. Therefore, the acceptance criterion after the bottom layer coating emphasizes overall evaporation convergence, the acceptance criterion after the intermediate layer coating emphasizes stable spreading, and the acceptance criterion after the top layer coating emphasizes particle constraint and waveguide flatness.

[0054] This implementation calculates a consistency relationship discriminant for each interpretation cycle. in, Indicates the number of coating layers In the Consistency relationship discrimination results for each reading cycle This indicates the phase margin of the previous reading cycle for the same coating layer. Only when... and Only when the release ring is activated will it output the spray gun start command for the next coating layer; if And two consecutive sets of interpretations satisfy If the current workpiece is determined to have completed the final layer of coating, it is allowed to exit the coating area. If any cycle If the tail end referee ring immediately outputs a no-jet control command within the same cycle, and outputs at least one of the following commands based on the mismatch type: leading attachment ring momentum adjustment command, peripheral recovery ring negative pressure adjustment command, sector backflush command, and waveguide reconstruction control command.

[0055] The following describes the working process. After the shock absorber housing is coated with the base layer, the spray gun is closed while the near-wall airflow waveguide remains continuous. The pre-charge shaping ring, the leading attachment ring, the rear locking attachment ring, and the outer recovery ring continue to maintain the basic or compensated state of the current active sector. A set of coded dual pulses is injected into the phase interpretation ring. The upstream and downstream sensor ports collect three types of quantities—pressure, solvent absorption, and particle scattering—according to a unified timestamp and assemble them into a unified data frame. The controller is calculated using a unified data frame. , , and Then compare it with the permissible range corresponding to the end of the base coat to obtain If two consecutive groups If both are 1, then the release ring allows the intermediate layer spray gun to open and changes the current layer index from 1 to 1. Switch to After the intermediate layer is sprayed, repeat the above process, but read the corresponding allowable range for the intermediate layer; after the top layer is sprayed, similarly read the corresponding allowable range for the top layer, and in two consecutive sets... The continuous spraying cycle of the current workpiece ends when all values ​​are 1. After each level switch, the controller writes the current level index, current phase margin, current consistency relationship judgment result, current sector compensation value, and current write-back status into the cycle record area for inheritance in the next judgment cycle.

[0056] In this implementation, the situation where the consistency relationship between the tail-end referee loops is not established is divided into three categories of advanced anomaly scenarios. The first category is the overall excessive wetness scenario, whose triggering condition is... , and The simultaneous occurrence of these conditions indicates that the near-wall airflow waveguide propagation is slowing down, evaporation has not yet converged, and the confinement of the recovery pressure is weakening. At this time, the tail-end referee ring outputs a no-jet control command, an outer recovery ring negative pressure increase command, and a leading attachment ring momentum reduction command. Among these, the outer recovery ring negative pressure is increased by 0.20 kPa, the leading attachment ring outlet velocity is reduced by 0.5 m / s, and the current sector compensation value is frozen for two reading cycles. If the conditions are still not met after two reading cycles... Then, a waveguide reconstruction control command is further output, increasing the outlet velocity of the post-locked attachment ring by 0.3 m / s and maintaining it for 1.2 s. The second type is a localized recovery containment leakage scenario, whose triggering condition is... , and This indicates that the main propagation path remains continuous, but the outer recovery ring's constraint on the active sector is insufficient. At this time, the tail-end referee ring outputs a spray prohibition control command, a sector backflush command, and a local waveguide reconstruction control command. The sector backflush command only applies to the active sector and the adjacent sector on one side, lasting 0.25 seconds. The local waveguide reconstruction control command further tightens the negative pressure of the corresponding partition's negative pressure window by 0.15 kPa and increases the duty cycle of the corresponding second slit nozzle by 0.04. The third category is the spray gun atomization drift or slit contamination scenario, triggered by two consecutive sets of interpretations. and If the reference pulse propagation time enters the stable range while the verification pulse propagation time exceeds the upper limit of the stable range by more than 0.8ms, the tail-end referee ring outputs a spray prohibition control command, a spray gun recalibration command, and a slit cleaning command. The spray gun recalibration command causes the spray gun to perform atomization pressure self-calibration in a non-painting state. The slit cleaning command causes the front guide attachment ring and the rear locking attachment ring to perform a 0.4s high-flow flush before allowing the next set of coded dual-pulse interpretation.

[0057] To avoid conflicts in the write-back order between different abnormal scenarios, this implementation method performs write-back control according to priority. The overall over-wet scenario has the highest priority, followed by the local recovery pressure leakage scenario, and then the spray gun atomization drift or slit contamination scenario. If multiple scenario trigger conditions are met simultaneously in the same cycle, only the write-back actions of the highest priority scenario are executed, and the remaining scenarios are recorded in the diagnostic record area. The inheritance rules for the next cycle after write-back are as follows: If the current cycle triggers the overall over-wet scenario, the sector compensation value in the freezing angle position deflection diagram of the next cycle is only allowed to update the negative pressure of the outer recovery ring; if the current cycle triggers the local recovery pressure leakage scenario, the next cycle only inherits the locally reconstructed duty cycle and negative pressure in the current active sector and its adjacent sectors; if the current cycle triggers the spray gun atomization drift or slit contamination scenario, the next cycle retains the basic propagation map and angle position deflection diagram, but the spray gun status remains prohibited from spraying until the re-verification results are written to the cycle record area.

[0058] In one embodiment, after the intermediate layer of the shock absorber housing is coated, the current layer index is retrieved. Active sector capture The current engine speed is 220 rpm. The phase detection loop injects the third set of coded double pulses, recording in the unified data frame. ms ms ms ms, record , , , ,Record , , , The baseline value of unpainted absorption in the basic propagation pattern of the same sector is taken as... The controller obtains this information. ms ms ms , Substituting the corresponding license range from the intermediate layer, we get... Because the phase margin of the same interpretation cycle at the same level is taken as ,and , , and All fall into the corresponding interval of the middle layer, therefore If the previous reading cycle also had... If this is enabled, the release ring will release the surface spray gun activation command within 20ms after the current cycle ends, and switch the layer index to [new value]. If only under the same data frame conditions... and If we change them to 0.92 and 0.90 respectively, then... It drops to 0.310, below the lower limit of the intermediate layer constraint interval. The system executes spray control commands, sector backflush commands, and local waveguide reconstruction commands according to the local recovery and containment leakage scenario.

[0059] This implementation elevates the coded dual-pulse approach from a simple retesting method to a clearly defined dual-channel diagnostic carrier. The reference pulse provides the main propagation state of the near-wall airflow waveguide after the current coating layer, while the verification pulse determines whether the same path maintains the same attenuation and constraint conditions within a short time interval. Therefore, the upstream and downstream sensors do not collect isolated measurements but rather unified data frames organized around the same near-wall airflow waveguide, the same sector, and the same coating layer. The controller then uses the coating layer index to call different permissible intervals, allowing the bottom, intermediate, and top layers to perform interpretations according to different convergence targets, thus avoiding compressing all coating layers into the same fixed beat. Consistency Relationship Discrimination Quantity The introduction of this feature further hardens the logical order between propagation time difference, solvent absorption peak drift, particle scattering envelope attenuation, and phase margin, ensuring that the permission release loop and tail-end adjudication loop no longer rely on empirical data from a single sensor value for release. Multi-branch write-back control further guarantees that if any of the following scenarios occur—over-wetting, localized recovery pressure leakage, or spray gun atomization drift—the system immediately implements a spray ban, and then adjusts the near-wall airflow waveguide boundary according to the corresponding priority, rather than continuing to operate under the original conditions.

[0060] The above description is merely a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be modified within the scope of the concept described herein by means of the above teachings or the technology or knowledge in related fields.

Claims

1. A continuous airflow guiding method for multi-layer spraying of shock absorber housings, characterized in that, include: It conveys and drives the shock absorber housing to rotate around its own axis; A basic annular flow field is established on the outer periphery of the shock absorber housing using a pre-charge shaping ring. A tangential thin-layer airflow is output to the surface of the shock absorber housing using a first slit nozzle set with a leading attachment ring. The tangential thin-layer airflow is then locked a second time using a second slit nozzle set with a rear locking attachment ring. A zoned negative pressure window set with an outer recovery ring forms a recovery pressure enclosure outside the tangential thin-layer airflow, thereby forming a near-wall airflow waveguide on the outer periphery of the shock absorber housing. Paint droplets are tangentially biased and fed into the near-wall airflow waveguide and transported and deposited along the surface of the shock absorber housing. After the current coating layer is completed, a coded double pulse, including a reference pulse and a verification pulse, is injected into the near-wall airflow waveguide using a phase interpretation ring. The upstream and downstream sensing ports set with corresponding tail-end referencing rings read the arrival time of the pressure peak, the drift of the solvent absorption peak, and the particle count corresponding to the coded double pulse. Scattering envelope attenuation; Calculate the bearing phase margin based on the propagation time difference corresponding to the arrival time of the pressure wave peak, the solvent absorption peak drift, and the particle scattering envelope attenuation; Utilize the permission release ring to release the spray gun start command for the next spray layer when the bearing phase margin corresponding to two consecutive sets of coded double pulses both enter the permission interval corresponding to the current spray layer, the propagation time difference corresponding to the arrival time of the pressure wave peak enters the stable interval, the solvent absorption peak drift enters the convergence interval, and the particle scattering envelope attenuation enters the constraint interval; When the propagation time difference corresponding to the arrival time of the pressure wave peak, the solvent absorption peak drift, and the particle scattering envelope attenuation do not satisfy the consistency relationship, use the tail-end referee ring to output spray prohibition control commands and waveguide reconstruction control commands to the leading attachment ring, the rear locking attachment ring, the peripheral recovery ring, and the spray gun.

2. The continuous airflow guiding method according to claim 1, characterized in that, The pre-charged shaping ring injects coded double pulses into the basic annular flow field in an unpainted state, and establishes a basic propagation spectrum based on the propagation time difference, solvent absorption peak drift, and particle scattering envelope attenuation calculated from the arrival time of the corresponding pressure wave peak.

3. The continuous airflow guiding method according to claim 2, characterized in that, The basic propagation spectrum includes the correspondence between the shock absorber housing rotation speed, the outer peripheral characteristic angle position and the near-wall airflow waveguide deflection, and the correspondence constitutes the angular position deflection diagram.

4. The continuous airflow guiding method according to claim 1, characterized in that, The leading attachment ring is provided with a first slit nozzle arranged in segments along the circumference, and the rear locking attachment ring is provided with a second slit nozzle arranged in segments along the circumference. The first slit nozzle and the second slit nozzle are staggered in the axial direction and arranged with phase delay in the circumferential direction.

5. The continuous airflow guiding method according to claim 1, characterized in that, The outer recovery ring is provided with a partitioned negative pressure window that rotates in the opposite direction to the near-wall airflow waveguide. The partitioned negative pressure window forms a phase-following recovery pressure enclosure around the near-wall airflow waveguide.

6. The continuous airflow guiding method according to claim 1, characterized in that, The encoded dual pulse includes a reference pulse and a verification pulse. The tail-end referee ring reads the arrival time of the pressure wave peak, the amount of solvent absorption peak drift, and the amount of particle scattering envelope attenuation corresponding to the reference pulse and the verification pulse through the upstream and downstream sensing ports, respectively.

7. The continuous airflow guiding method according to claim 6, characterized in that, The phase margin is determined by the propagation time difference corresponding to the arrival time of the pressure wave peak, the drift of the solvent absorption peak, and the attenuation of the particle scattering envelope. The permissible range is set according to the number of spraying layers.

8. The continuous airflow guiding method according to claim 1, characterized in that, The consistency relationship includes: when the propagation time difference corresponding to the arrival time of the pressure wave peak enters the stable range, the drift of the solvent absorption peak simultaneously enters the convergence range, and the attenuation of the particle scattering envelope simultaneously enters the constraint range.

9. The continuous airflow guiding method according to claim 8, characterized in that, When the consistency relationship is not established, the tail end referee ring outputs a no-spray control command, and outputs at least one of the following commands: leading attachment ring momentum adjustment command, peripheral recovery ring negative pressure adjustment command, and sector backflush command.

10. The continuous airflow guiding method according to claim 3, characterized in that, When the spring tray root, weld rib and mounting ear plate enter the corresponding angular position of the angular position deflection diagram, adjust the duty cycle of the corresponding sector of the front guide attachment ring and the rear locking attachment ring according to the angular position deflection diagram, and simultaneously tighten the negative pressure window of the corresponding partition of the outer recovery ring.

Images