A 3D printer heat dissipation device and a heat dissipation method

Abstract

The application discloses a 3D printer heat dissipation device and a heat dissipation method. The device comprises a rectangular heat dissipation frame formed by splicing four L-shaped corner frame units, a top plate, a plurality of heat dissipaters, a temperature detection assembly and a controller. The controller calculates historical unreleased heat storage according to historical printing heat input data, generates a future new heat load sequence according to future printing task data, and generates a benchmark predicted heat dissipation capacity sequence in combination with the cavity temperature, the environment temperature and the current heat dissipation state, and then determines a rolling heat to be dissipated sequence and a predicted out-of-limit time. Then, the comprehensive heat dissipation effective delay and the candidate early trigger time are determined according to the current printing geometry data and the heat dissipation response parameters of the candidate heat dissipation level, the lowest candidate heat dissipation level that makes the rolling heat to be dissipated in the predicted time domain lower than the upper limit of the allowed heat to be dissipated is selected, and the heat dissipation device is controlled in advance according to the lowest candidate heat dissipation level. The application can reduce the risk of the cavity temperature exceeding the limit caused by the historical heat storage and the heat dissipation response lag.

Description

Technical Field

[0001] This invention relates to the field of 3D printing equipment technology, and specifically to a heat dissipation device and method for a 3D printer. Background Technology

[0002] During continuous printing, 3D printers generate heat from the nozzle heating assembly, heated bed, drive motor, and control circuitry. Newly deposited printing material also carries heat into the printing area. For 3D printers with a casing, top frame, or relatively enclosed printing space, this heat can easily accumulate inside. Excessive internal temperature can soften the deposited material and affect the stable operation of the nozzle assembly, drive assembly, and control circuitry. Therefore, heat sinks are typically installed on the top or side of the printer to ventilate and dissipate heat inside.

[0003] Existing cooling systems typically incorporate temperature sensors inside the printer and use fixed temperature thresholds to control the fan's operation. The fan starts when the detected temperature reaches the activation threshold and shuts off when the temperature drops to the deactivation threshold. Some control methods also calculate the temperature shortly after the current rate of temperature rise and set a fixed advance activation time.

[0004] However, the current air temperature inside the printer cannot fully reflect the actual heat accumulation status of the printer. When printing large-section layers, high-fill-rate layers, or high-temperature materials, the heated bed, printed material, printer frame, and housing absorb and store heat. Even if the current air temperature is still below the heat dissipation threshold, the heat that has not yet been released in these components may continue to be released in subsequent printing stages, and this heat will be added to the new heat generated in subsequent printing processes, resulting in a delayed temperature rise. Controlling the printer based solely on the current temperature or short-term temperature rise rate makes it difficult to identify this historical heat accumulation that has not yet been released.

[0005] Furthermore, the process from receiving the start command to a noticeable drop in the printer's internal temperature is not instantaneous. Instead, it involves a series of processes: radiator startup, airflow establishment, airflow delivery to the printing area, and the printer's internal temperature response. This delay in effective heat dissipation is affected by factors such as radiator rotation speed, the current height of the printed workpiece, the cross-sectional area of ​​the workpiece, the airflow channels, and the radiator's performance status, and varies throughout the printing process. Using a fixed, early start time may result in premature heat dissipation in the initial printing phase, while in the later stages of printing, when the workpiece height increases and airflow channels are obstructed, heat dissipation may start too late. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a heat dissipation device and method for a 3D printer. It can identify historical heat storage inside the printer that has not yet been released, predict the new heat load and expected heat dissipation based on future printing tasks, and determine the actual heat dissipation activation delay of the radiator according to the current printing conditions, so as to activate the radiator in advance before the heat to be dissipated reaches the allowable upper limit.

[0007] The technical solution adopted in this invention is as follows:

[0008] A 3D printer heat dissipation device includes:

[0009] A rectangular heat dissipation frame is formed by splicing four L-shaped corner frame units end to end, and the free ends of two adjacent L-shaped corner frame units are connected by straight splicing pieces.

[0010] Top plate, located on top of the rectangular heat dissipation frame;

[0011] Multiple radiators, each of the L-shaped corner frame units is provided with a heat dissipation mounting cavity and a heat dissipation port communicating with the heat dissipation mounting cavity, the radiator is installed in the heat dissipation mounting cavity, and the ventilation end of the radiator is opposite to the corresponding heat dissipation port;

[0012] Temperature detection components are used to collect internal temperature data and ambient temperature data of the 3D printer.

[0013] The controller, installed in the controller mounting cavity of one of the L-shaped corner frame units, is electrically connected to multiple heat sinks and the temperature detection components, and communicatively connected to the 3D printer control unit. The controller acquires historical printing heat input data, future printing task data, and current printed part geometry data. Based on the historical printing heat input data and the cavity temperature data, it generates historical unreleased heat storage data. Based on the future printing task data, it generates a future new heat load sequence. Based on the ambient temperature data and the heat dissipation level of each heat sink, it generates an expected heat dissipation sequence, thereby generating a rolling heat dissipation sequence and a predicted over-limit time. Based on the current printed part geometry data, it generates a comprehensive heat dissipation activation delay to generate the heat sink's early trigger time and heat dissipation level.

[0014] A 3D printer heat dissipation method, executed by a controller of the 3D printer heat dissipation device, includes:

[0015] S1. Obtain historical printing heat input data, future printing task data, cavity temperature data, ambient temperature data, current printed part geometry data, heat storage attenuation parameters, cavity safe temperature limit corresponding to printing material, printer internal equivalent heat capacity, and heat dissipation response parameters corresponding to each candidate heat dissipation level.

[0016] S2. Generate each historical heat input amount based on the historical printed heat input data, calculate the remaining heat of each historical heat input amount at the current moment using the corresponding heat storage attenuation parameter, and accumulate each remaining heat to obtain the historical unreleased heat storage.

[0017] S3. Process the future printing task data according to multiple consecutive prediction periods to obtain the future new heat load sequence, and obtain the baseline expected heat dissipation sequence based on the cavity temperature data, the ambient temperature data and the current radiator operating status.

[0018] S4. Accumulate the historical unreleased heat storage and the future new heat load sequence according to the predicted time period, and subtract the baseline expected heat release sequence to obtain the rolling heat release sequence; obtain the allowable heat release limit based on the cavity safety temperature limit, the cavity temperature data and the printer's internal equivalent heat capacity, and determine the predicted time of exceeding the limit.

[0019] S5. Based on the current printed part geometry data and the heat dissipation response parameters corresponding to each of the candidate heat dissipation levels, obtain the comprehensive heat dissipation activation delay amount, advance the predicted over-limit time by the corresponding comprehensive heat dissipation activation delay amount, and obtain the candidate early trigger time.

[0020] S6. Generate a candidate rolling heat dissipation sequence based on each candidate early trigger time and the corresponding candidate heat dissipation level. Determine the lowest candidate heat dissipation level in the prediction time domain where none of the rolling heat dissipation levels have reached the upper limit of the allowable heat dissipation level, determine the corresponding candidate early trigger time as the target early trigger time, and control the radiator operation according to the target early trigger time and the target heat dissipation level.

[0021] The beneficial effects of this invention are:

[0022] This invention processes historical printing heat input separately for the nozzle, heated bed, deposition material, and drive components, and calculates historical unreleased heat storage by combining corresponding heat storage attenuation parameters, thus quantifying structural heat storage that is not directly reflected by the current cavity temperature. Then, based on future printing tasks, it generates a sequence of future additional heat loads, and combines the temperature difference inside and outside the cavity with the current radiator operating status to generate a baseline expected heat dissipation sequence. Based on this, a rolling heat dissipation sequence is formed and the predicted over-limit time is determined, thereby identifying the risk of delayed temperature rise in advance.

[0023] Furthermore, based on the current printing height, the current layer projection area, the distance between the printing area and the heat sink, and the heat dissipation response parameters corresponding to the candidate heat dissipation levels, a comprehensive heat dissipation activation delay and candidate early trigger times are generated. The lowest candidate heat dissipation level is selected so that the rolling heat to be dissipated in the predicted time domain is lower than the upper limit of the allowable heat to be dissipated, thereby achieving coordinated control of heat dissipation timing and heat dissipation intensity, reducing the probability of heat dissipation start-up lag, cavity temperature exceeding the limit, and excessive heat dissipation. Attached Figure Description

[0024] Figure 1 This is a schematic diagram showing the connection between the 3D printing heat dissipation device and the printer body in an embodiment of the present invention;

[0025] Figure 2 This is a schematic diagram of the overall structure of a 3D-printed heat dissipation device according to an embodiment of the present invention;

[0026] Figure 3 This is a structural schematic diagram of an L-shaped corner frame unit and a straight splicing component according to an embodiment of the present invention;

[0027] Figure 4 This is an overall flowchart of the 3D printer heat dissipation method according to an embodiment of the present invention;

[0028] Figure 5 This is a flowchart illustrating the generation of historical unreleased heat storage in one embodiment of the present invention.

[0029] Figure 6 This is a flowchart illustrating the generation of rolling heat to be discharged and predicted over-limit time according to an embodiment of the present invention.

[0030] Figure 7 A flowchart for generating the comprehensive heat dissipation activation delay and candidate early triggering time according to an embodiment of the present invention;

[0031] Figure 8 This is a flowchart illustrating the determination of target heat dissipation level and target early triggering time according to an embodiment of the present invention.

[0032] Figure 9 This is a flowchart illustrating the boundary state processing and heat dissipation parameter feedback update according to an embodiment of the present invention.

[0033] Explanation of reference numerals in the attached figures:

[0034] 10-Rectangular heat dissipation frame, 11-L-shaped corner frame unit, 111-First frame edge, 112-Second frame edge, 113-Plug-in slot;

[0035] 20 - Straight-line splice, 21 - First interlocking section, 22 - Second interlocking section

[0036] 30-Top plate;

[0037] 40 - Radiator, 41 - Radiator mounting cavity, 42 - Radiator opening;

[0038] 50 - Controller, 51 - Controller mounting cavity. Detailed Implementation

[0039] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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.

[0040] like Figures 1-3 As shown, a 3D printer heat dissipation device according to an embodiment of the present invention includes a rectangular heat dissipation frame 10, a top plate 20, multiple heat sinks, a temperature detection component, and a controller; the 3D printer heat dissipation device is installed as a whole at the top opening of the 3D printer body.

[0041] like Figure 3 As shown, a rectangular heat dissipation frame 1 is set on the top of the 3D printer and covers or surrounds the heat dissipation area on the top of the 3D printer.

[0042] The rectangular heat dissipation frame 10 is formed by splicing together four L-shaped corner frame units 11 with the same or compatible structures end to end.

[0043] Each L-shaped corner frame unit 11 includes a first frame side 111 and a second frame side 112. The first frame side 111 and the second frame side 112 are connected perpendicularly to each other, so that the L-shaped corner frame unit 11 is L-shaped in the top view direction.

[0044] In one embodiment, the first frame edge 111 and the second frame edge 112 can be integrally formed. The L-shaped corner frame unit 11 can be made of aluminum alloy profile, engineering plastic, sheet metal, or fiber-reinforced composite material. Preferably, the L-shaped corner frame unit 11 is made of aluminum alloy profile to balance structural strength and its own heat dissipation capacity.

[0045] The free ends 113 of the first frame edge 111 and the second frame edge 112 are respectively provided with insertion slots 114. The insertion slots 114 extend along the length direction of the corresponding frame edge and extend from the end face of the free end 113 into the corresponding frame edge.

[0046] like Figure 3 As shown, two adjacent L-shaped corner frame units 11 are connected by a straight splice 12. The straight splice 12 includes a first insertion segment 121 and a second insertion segment 122 connected along the same straight line.

[0047] During assembly, the first insertion segment 121 is inserted into the insertion slot 114 of an L-shaped corner frame unit 11, and the second insertion segment 122 is inserted into the insertion slot 114 of another adjacent L-shaped corner frame unit 11, until the free ends 113 of the two adjacent L-shaped corner frame units 11 abut against each other.

[0048] After the two adjacent free ends 113 abut against each other, the first insertion segment 121 and the second insertion segment 122 are contained within the containment space formed by the two insertion slots 114, and the straight splice 12 does not protrude from between the two free ends 113.

[0049] The straight splice 12 and the insertion groove 114 can be fitted with clearance, transition, or interference fit.

[0050] In one embodiment, the straight splice 12 and the insertion slot 114 are fitted with a transition fit, so that the straight splice 12 can be inserted into the insertion slot 114 and the relative movement of two adjacent L-shaped corner frame units 11 in the direction perpendicular to the length of the corresponding frame side is restricted.

[0051] Alternatively, the straight splicing component 12 and the L-shaped corner frame unit 11 can be connected by screws. Specifically, the L-shaped corner frame unit 11 and the straight splicing component 12 have corresponding screw holes, and the screws are threaded into the screw holes to fix the straight splicing component 12 inside the L-shaped corner frame unit 11.

[0052] The straight splice 12 can be a solid strip or a profile with a hollow cavity. The first insertion section 121 and the second insertion section 122 can have a rectangular cross-section, a circular cross-section, an elliptical cross-section, or an irregular cross-section that matches the insertion groove 114.

[0053] The top plate 2 is located on top of the rectangular heat dissipation frame 1 and is connected to four L-shaped corner frame units 11. The top plate 2 can be installed on the rectangular heat dissipation frame 1 by means of screw connection, snap-fit, plug-in connection or sliding groove connection.

[0054] In one embodiment, the top plate 2 is connected to four L-shaped corner frame units 11 by screws distributed circumferentially. The top plate 2 can be made of transparent or opaque material. Preferably, the top plate 2 is made of transparent polycarbonate sheet to allow observation of the printing process from the top of the 3D printer. The top plate 2 can also be made of aluminum alloy sheet or other material with mechanical strength and heat resistance.

[0055] like Figure 3As shown, each L-shaped corner frame unit 11 is provided with at least one heat dissipation mounting cavity 115 and at least one heat dissipation port 116. The heat dissipation mounting cavity 115 is formed by an inward recess from the outer surface of the corresponding L-shaped corner frame unit 11. The outer contour of the heat dissipation mounting cavity 115 matches the mounting edge 31 of the corresponding heat sink 3. The heat dissipation port 116 penetrates the bottom of the heat dissipation mounting cavity 115 and communicates with the inner space enclosed by the rectangular heat dissipation frame 1. The heat sink 3 is disposed in the heat dissipation mounting cavity 115, and the mounting edge 31 of the heat sink 3 can be fixed to the bottom of the heat dissipation mounting cavity 115 by multiple screws 33. The ventilation end 32 of the heat sink 3 is opposite to the corresponding heat dissipation port 116, so that the airflow generated by the heat sink 3 during operation can flow between the internal space of the 3D printer and the external environment through the heat dissipation port 116.

[0056] In one embodiment, the radiator 3 is an axial flow fan with its air inlet facing the interior of the 3D printer and its air outlet facing the external environment, allowing the high-temperature air inside the 3D printer to be exhausted through the heat dissipation port 116. External air can enter the printer through the existing air inlet, bottom gap, or casing opening.

[0057] In another embodiment, some heat sinks 3 can be configured to supply air into the 3D printer, while others can be configured to exhaust air outwards, thereby forming a directional airflow path. The specific airflow direction of the heat sinks 3 can be determined based on the existing air intake and exhaust structures of the 3D printer.

[0058] The radiator 3 can also use a DC brushless fan with a rated voltage of 12 volts or 24 volts, and the speed can be adjusted by a pulse width modulation signal.

[0059] The temperature detection assembly 4 includes at least one intracavity temperature sensor 41 and at least one ambient temperature sensor 42. The intracavity temperature sensor 41 is disposed on the side of the rectangular heat dissipation frame 1 facing the interior of the 3D printer.

[0060] In one embodiment, an internal temperature sensor 41 is respectively disposed on the inner side of each of the four L-shaped corner frame units 11. The controller 5 can take the maximum value among the multiple internal temperature sensor values ​​as the current internal temperature, or it can weight the detection values ​​according to the distance between the current printing area and each internal temperature sensor 41 to obtain the current internal temperature. The ambient temperature sensor 42 is disposed on the side of the rectangular heat dissipation frame 1 or the top plate 2 facing the external environment, and is spaced apart from the air outlet of the heat sink 3 to reduce the influence of the exhaust hot air on the ambient temperature detection results. The internal temperature sensor 41 and the ambient temperature sensor 42 can be thermistors, digital temperature sensors, or thermocouples.

[0061] One of the L-shaped corner frame units 11 is provided with a controller mounting cavity 117, and the controller 5 is disposed in the controller mounting cavity 117.

[0062] The controller 5 may include a microprocessor, a memory, a fan drive circuit, a temperature signal acquisition circuit, and a communication circuit. The controller 5 is connected to each heat sink 3, the cavity temperature sensor 41, and the ambient temperature sensor 42 via wires 7.

[0063] The controller 5 is equipped with multiple heat sink drive channels, each heat sink drive channel corresponds to one heat sink 3, so that the controller 5 can control the start, stop and drive duty cycle of each heat sink 3 respectively.

[0064] Controller 5 communicates with the 3D printer control unit 6 to read the current printing program, printer operation log, and printing status. The communication connection can be via serial communication, USB communication, CAN communication, Ethernet communication, or wireless communication.

[0065] In one embodiment, the controller 5 reads the G-code program from the 3D printer control unit 6 and divides the G-code program into executed path instructions and unexecuted path instructions according to the execution pointer of the G-code program.

[0066] like Figures 4-9 As shown, in another embodiment of the present invention, the present invention also proposes a 3D printer heat dissipation method, executed by the controller of the 3D printer heat dissipation device, comprising:

[0067] S1. Obtain historical printing thermal input data, future printing task data, cavity temperature data, ambient temperature data, current printed part geometry data, heat storage attenuation parameters, the upper limit of the cavity safe temperature corresponding to the printing material, the printer's internal equivalent heat capacity, and the heat dissipation response parameters corresponding to each candidate heat dissipation level.

[0068] This step is used to complete the current operating condition perception, historical data backtracking, future task prediction and calibration parameter matching, and provide a complete and unified input data boundary for the historical heat storage calculation from S2 to S6, future heat load prediction, temperature over-limit determination, heat dissipation effective delay calculation and heat dissipation level decision.

[0069] In one embodiment, step S1 includes: reading the current printing program, printer operation log, temperature acquisition records, radiator control records, and a pre-stored parameter library. The current printing program is parsed to obtain the printing material identifier, executed path instructions, and unexecuted path instructions. Based on the executed path instructions, the current printed part geometry data is generated, including the current printing height, the current layer projected area, and the distance between the current printing area and each radiator. Based on the unexecuted path instructions, future printing task data is generated, including the subsequent printing path, printing speed, expected material extrusion amount, nozzle set temperature, heated bed set temperature, and drive component runtime. Historical printing heat input data with heat source identifiers and timestamps is extracted from the printer operation log; cavity temperature data and ambient temperature data are extracted from the temperature acquisition records; and the current radiator operating status is extracted from the radiator control records. Based on the printing material identifier, the upper limit of the cavity safe temperature is obtained from the pre-stored parameter library; and the heat storage attenuation parameter, the printer's internal equivalent heat capacity, and the heat dissipation response parameters corresponding to each candidate heat dissipation level are obtained from the pre-stored parameter library.

[0070] In this embodiment, the controller, through a communication link established with the 3D printer control unit and in conjunction with a local non-volatile storage unit, synchronously reads the current printing program, printer operation log, temperature acquisition records, radiator control records, and pre-stored parameter library. The current printing program is typically a G-code format print control file, containing complete process instructions such as print path, extrusion volume, temperature setting, and movement speed. The printer operation log records the operating status of each heat source throughout the printing process, including printhead heating start / stop, heated bed heating start / stop, motor operating status, and material extrusion volume. Each record is marked with a heat source identifier for tracing historical heat input. The temperature acquisition record stores historical and current real-time values ​​from the cavity temperature sensor and ambient temperature sensor at a fixed sampling period for temperature status sensing and thermal model verification. The radiator control record records the start / stop commands, drive duty cycle, and runtime of each radiator, using timestamps to determine the current heat dissipation conditions and historical heat dissipation effects. The pre-stored parameter library is a structured parameter set stored locally by the controller, including material thermal property parameters, printer structural thermal parameters, and radiator performance parameters, categorized by material type and hardware model, and can be directly accessed via index.

[0071] After acquiring the current printing program, the controller first reads the program's execution pointer position. Using the instruction line number corresponding to the execution pointer as a boundary, it divides the complete printing program into two parts: executed path instructions and unexecuted path instructions. Simultaneously, the controller extracts the printing material identifier from the temperature configuration instructions and material annotation information at the beginning of the printing program. This identifier will serve as the index for subsequently retrieving material-related parameters. The executed path instructions correspond to all process actions completed from the start of printing to the current moment, reflecting the current state of the printed part and the historical heat input process. The unexecuted path instructions correspond to all process actions to be executed after the current moment, forming the basis for predicting future printing conditions and additional heat loads.

[0072] Based on the coordinate information in the executed path instructions, the controller generates the current printed part's geometric data, specifically including the current printing height, the current layer's projected area, and the distance between the current printing area and each heat sink. The current printing height is obtained by extracting the maximum Z-axis coordinate from all executed path instructions; it characterizes the degree to which the printed part obstructs the cooling airflow in the vertical direction. The higher the printing height, the greater the resistance to airflow through the printing area. The current layer's projected area is obtained by extracting the planar coordinates of all paths of the highest printing layer and calculating the area of ​​its outer polygon; it characterizes the proportion of airflow obstruction by the printed part in the horizontal cross-section; the larger the projected area, the smaller the effective airflow cross-sectional area within the cavity. The distance between the current printing area and each heat sink is obtained by calculating the straight-line distance with the geometric center of the current printing layer as the starting point and the center of each heat sink's vent as the ending point; it quantifies the path length of the cooling airflow from the vent to the printing core area.

[0073] Based on the unexecuted path instructions, the controller parses the data according to the execution sequence to generate future printing task data, specifically including the subsequent printing path, printing speed, expected material extrusion amount, printhead set temperature, heated bed set temperature, and drive component runtime. The subsequent printing path is arranged according to the execution time sequence of the instructions and can be divided and allocated according to the length of the predicted time period; the printing speed, combined with the printer's preset acceleration and deceleration curve, can be decomposed into constant speed runtime and acceleration / deceleration runtime to distinguish the heat generation of the drive components under different motion states; the expected material extrusion amount can be obtained by statistically analyzing the total E-axis displacement within the corresponding time period and converting it with the density of the printing material, and is used to calculate the heat brought into the cavity by the deposited material; the printhead set temperature and heated bed set temperature are extracted from the temperature control code in the unexecuted instructions and are used to match the historical heating duty cycle under the corresponding operating conditions to predict the actual heating time of the printhead and heated bed; the drive component runtime is the cumulative running time of each motion axis motor within the corresponding time period, used to estimate the total heat generation of the drive components.

[0074] After completing the printing program parsing, the controller extracts operational status data from the corresponding historical records, including historical printing heat input data, temperature data, and the current radiator operating status. Historical printing heat input data consists of all heat source operation records extracted from the printer's operation log from the start of printing to the current moment, each with a heat source identifier and timestamp. These records are categorized and archived into four types of heat sources: printhead, heated bed, deposited material, and drive components. This data is used for subsequent calculation of the remaining heat storage capacity of each historical heat input at the current moment. Temperature data consists of the current cavity temperature and ambient temperature data extracted from the temperature acquisition records. The cavity temperature can be obtained by using the maximum value from multiple cavity temperature sensors or by weighting the values ​​based on the distance between each sensor and the current printing area, to accurately characterize the overall thermal state within the cavity. The ambient temperature is taken from the ambient temperature sensor located far from the radiator exhaust vent to reduce interference from exhaust hot air. Both types of temperature data are used in the heat dissipation calculation and temperature margin calculation. The current radiator operating status is obtained by extracting the radiator number and corresponding heat dissipation level currently in operation from the radiator control records. This serves as the basis for calculating the expected heat dissipation sequence.

[0075] The controller uses the extracted printing material identifier as an index to retrieve matching basic parameters from the pre-stored parameter library. These parameters include the upper limit of the safe temperature inside the cavity, the heat storage attenuation parameter, the equivalent heat capacity inside the printer, and the heat dissipation response parameters corresponding to each candidate heat dissipation level. The upper limit of the safe temperature inside the cavity is the highest ambient temperature inside the cavity that allows the corresponding printing material to maintain stable molding. Exceeding this temperature will cause the deposited material to soften and deform, and the interlayer bonding strength to decrease. It is the benchmark threshold for judging temperature exceeding the limit. The heat storage attenuation parameter is set with corresponding attenuation coefficients for four types of heat sources. It characterizes the rate at which the accumulated heat from different heat sources is released into the cavity air after the heat input of different heat sources stops or is reduced. This parameter can be pre-generated using temperature drop data from historical identification periods. The equivalent heat capacity inside the printer treats all heat storage components inside the printer, such as the metal frame, heated bed, cavity air, and printed parts, as a single homogeneous heat capacity. It characterizes the total heat absorbed required for the overall temperature inside the cavity to rise by 1°C, and is used to achieve quantitative conversion between temperature difference and heat difference. The heat dissipation response parameters corresponding to each candidate heat dissipation level are stored in categories from low to high, covering performance indicators such as heat sink start-up delay, airflow establishment delay, airflow speed, and heat dissipation power per unit time, providing a calibration basis for subsequent heat dissipation effectiveness delay calculation and heat dissipation capacity calculation.

[0076] S2. Generate each historical heat input based on the historical printed heat input data, calculate the remaining heat of each historical heat input at the current moment using the corresponding heat storage attenuation parameter, and accumulate each remaining heat to obtain the historical unreleased heat storage.

[0077] This step quantifies the total residual heat generated during all printing processes prior to the current moment, which has not yet been dissipated into the environment and remains stored in the printer cavity, heated bed, metal frame, printed parts, and other structures. It overcomes the limitation of existing technologies that rely solely on current air temperature to determine the thermal state, incorporating the delayed release of heat stored in solid-state components into the thermal balance calculation, thus providing a complete initial thermal state for subsequent temperature exceedance predictions.

[0078] In one embodiment, step S2 includes: dividing the historical printing thermal input data into nozzle thermal input data, heated bed thermal input data, deposited material thermal input data, and drive component thermal input data according to the heat source identifier.

[0079] Based on the nozzle heating power, nozzle heating duration, and nozzle heat conversion parameters in the nozzle heat input data, the historical heat input of the nozzle is obtained.

[0080] Based on the heating power, heating duration, and heat conversion parameters of the heated bed in the heated bed heat input data, the historical heat input of the heated bed is obtained.

[0081] Based on the material extrusion mass, specific heat capacity, extrusion temperature, and cavity temperature at the corresponding time in the heat input data of the deposited material, the historical heat input of the deposited material is obtained.

[0082] Based on the driving component's operating power, operating duration, and thermal conversion parameters in the driving component's thermal input data, the historical thermal input of the driving component is obtained.

[0083] The end time of the heat input period corresponding to each historical heat input is determined as the generation time of the historical heat input. Based on the time interval from the generation time to the current time and the heat storage attenuation parameter of the corresponding heat source, the remaining heat of each historical heat input at the current time is obtained. The remaining heat is then accumulated to obtain the historical unreleased heat storage.

[0084] Among them, the heat storage attenuation parameter is generated in advance based on the data of the decrease in cavity temperature over time during the historical identification period when the heat input of the corresponding heat source is reduced or stopped, the heat input status of other heat sources remains unchanged, and the radiator operation status remains unchanged.

[0085] It should be noted that the heat inside the printer originates from four independent heat sources: the printhead, the heated bed, the deposited material, and the drive components. Each heat source has a different heat storage carrier, heat transfer path, and natural decay rate. Therefore, separate heat input calculation models and heat storage decay models must be established for each heat source category to ensure the accuracy of the heat storage calculation results. Specifically, the heat carrier for the printhead heat source is a small-mass metal structure such as the heating block and nozzle, which diffuses heat quickly and decays rapidly. The heat carrier for the heated bed heat source is a large-mass metal platform, which has strong heat storage capacity and a slow decay rate, and is the primary source of historical heat storage. The heat carrier for the deposited material heat source is the printed consumable entity; the total heat storage gradually increases with the printing process, and the decay rate is related to the material's thermal conductivity. The heat carrier for the drive components heat source is the motor, transmission components, and control circuitry; the overall heat generation is relatively small, and the heat diffuses and decays quickly.

[0086] Furthermore, the historical heat input of the nozzle can be calculated using an effective electric heating conversion model, with the following formula:

[0087] ;

[0088] In the formula, This represents the total effective heat input corresponding to the i-th nozzle heat input record, in joules. This is the instantaneous heating power of the printhead during this period, measured in watts, and is calculated from the heating duty cycle and printhead rated power in the printer's operation log. This is the duration of the nozzle's heating within that time period, in seconds, calculated from the difference between the start and end timestamps of the corresponding record. Here, is the heat conversion parameter of the nozzle, and is a dimensionless coefficient with a value range of . This represents the proportion of heat that is ultimately transferred to the printer's interior from the printhead's electric heating power. The remaining heat is dissipated directly to the external environment through the printhead housing and wiring, and does not participate in the cavity's heat storage.

[0089] Furthermore, for the historical heat input of the heated bed, an electric heating conversion model derived from the nozzle can be used, and the calculation formula is as follows:

[0090] ;

[0091] in, This represents the total effective heat input corresponding to the i-th heated bed heat input record, in joules. This represents the instantaneous heating power of the heated bed during this period, expressed in watts. This refers to the duration of heating of the heated bed during this period, in seconds. The thermal conversion parameters of the heated bed are dimensionless coefficients that characterize the effective proportion of heating power transferred from the heated bed to the cavity.

[0092] Furthermore, the historical heat input of the deposited material can be calculated based on the principle of sensible heat transfer, that is, the total heat released during the cooling process of the high-temperature extruded material from the extrusion temperature to the cavity temperature. The calculation formula is as follows:

[0093] ;

[0094] in, Record the total heat brought into the cavity by the i-th deposited material, in joules; The mass of printing material extruded during this period is expressed in kilograms and is calculated by multiplying the extrusion length along the E-axis of the corresponding record by the density of the printing material. The specific heat capacity at constant pressure of the printing material is measured in joules per kilogram per degree Celsius and is retrieved from a pre-stored parameter library based on the printing material identifier. This refers to the material extrusion temperature during this period, expressed in degrees Celsius, and is consistent with the nozzle setting temperature at the corresponding moment. This represents the temperature of the air inside the cavity at that moment, in degrees Celsius.

[0095] Furthermore, the historical heat input of the drive components can be calculated using a power efficiency conversion model, which characterizes the heat generated by the motor windings and the heat retained inside the cavity due to circuit losses. The calculation formula is as follows:

[0096] ;

[0097] in, This represents the total effective heat input corresponding to the i-th driving component's operation record, expressed in joules. This represents the operating power of the drive motor and control circuit during this period, measured in watts, which can be calculated based on the motor's operating current and the supply voltage. This refers to the duration of operation of the driving component during this period, in seconds. is the thermal conversion parameter of the drive component, and is a dimensionless coefficient that characterizes the proportion of drive power consumption converted into effective heat within the cavity.

[0098] After obtaining the total heat from a single historical heat input, the remaining heat storage capacity at the current moment is further calculated. To simplify the real-time computation of the embedded controller while ensuring the accuracy of engineering calculations, the end time of the heat input period corresponding to each historical heat input is determined as the generation time of that historical heat input, equivalent to all heat being injected into the cavity at that moment, and this is used as the starting time of the heat storage decay process. The heat storage and release process inside the printer conforms to the lumped parameter heat conduction law, and the remaining heat decays exponentially with time. The general formula for calculating the remaining heat storage capacity of a single historical heat input is:

[0099] ;

[0100] In the formula, For the i-th historical heat input at the current moment The remaining heat storage capacity, expressed in joules; The total historical heat input of the heat source corresponding to the i-th item is represented by the subscript x, which can be replaced by h, b, mat, and drv, respectively, corresponding to four types of heat sources: nozzle, heated bed, deposited material, and drive component. The unit is joules. The heat storage attenuation coefficient corresponds to the heat source, and the unit is per second. The larger the coefficient value, the faster the heat is lost and the shorter the heat storage retention time. The current calculation time is in seconds; The time of generation of the i-th historical heat input is in seconds; The time interval from the moment the heat input is generated to the current moment is the decay time of the stored heat, in seconds. This is a natural exponential function, representing the nonlinear variation characteristics of heat storage decay. For four different types of heat sources, the calculation of individual remaining heat storage can be completed simply by replacing the total heat input and decay coefficient in the formula with the parameters corresponding to the category. The further back the heat input is from the current time, the lower the proportion of remaining heat; the smaller the decay coefficient of the heat source, the higher the proportion of heat retained.

[0101] Furthermore, by summing up the remaining heat storage corresponding to all historical heat input records, the total historical unreleased heat storage inside the printer at the current moment can be obtained. The calculation formula is as follows:

[0102] ;

[0103] In the formula, The total unreleased heat storage from all sources is expressed in joules; M represents the total number of all historical heat input records from the start of this printing to the current moment. This represents the remaining heat storage corresponding to the i-th record, expressed in joules. This value comprehensively reflects the total heat that has not yet been dissipated from all heat storage carriers inside the printer at the current moment. This heat will continue to be released into the air inside the cavity during subsequent printing processes, and will be superimposed on the additional heat load generated by subsequent printing processes, forming a delayed temperature rise. This is an initial heat item that cannot be ignored in the prediction of temperature exceeding the limit.

[0104] It should be noted that the heat storage attenuation parameters corresponding to various heat sources are pre-generated using a controlled variable identification method. The specific identification process is as follows: a single heat source is selected and heated until the cavity temperature reaches a stable state. All other heat sources are kept in standby mode with no additional heat input, while the radiator operation remains constant to eliminate interference from other heat factors. Then, the heating input of this heat source is stopped, and the cavity temperature decrease curve over time is recorded at a fixed sampling period. Based on the lumped parameter heat balance model, this temperature decrease process follows a first-order exponential decay law. By fitting the temperature decrease curve using the least squares method, the heat storage attenuation coefficient of the corresponding heat source can be obtained. This identification process can be calibrated before the equipment leaves the factory, or it can be automatically performed online during the printing process using suitable idle periods to continuously optimize the accuracy of the attenuation parameters to adapt to performance changes after long-term use of the equipment.

[0105] S3. Process future printing task data according to multiple consecutive prediction periods to obtain the future new heat load sequence, and obtain the baseline expected heat dissipation sequence based on cavity temperature data, ambient temperature data and current radiator operating status.

[0106] Step S3 takes the future printing task data, cavity temperature data, ambient temperature data and current radiator operating status output from step S1, and performs time-domain discretization prediction from the two dimensions of heat input and heat dissipation, and finally generates the future new heat load sequence and the baseline expected heat dissipation sequence.

[0107] In one embodiment, step S3 specifically includes: dividing the prediction time domain into multiple prediction time periods of equal length, and allocating unexecuted path instructions to the corresponding prediction time periods according to their execution time.

[0108] For each prediction period, based on the corresponding printhead set temperature and ambient temperature, the matching historical printhead heating duty cycle is extracted from the printer operation log, and the future heat input of the printhead is obtained based on the historical printhead heating duty cycle, the printhead rated power, and the length of the prediction period.

[0109] Based on the corresponding heated bed set temperature and ambient temperature, the matching historical heating duty cycle of the heated bed is extracted from the printer operation log, and the future heat input of the heated bed is obtained based on the historical heating duty cycle of the heated bed, the rated power of the heated bed, and the length of the predicted period.

[0110] The future heat input of the deposited material is obtained based on the corresponding expected material extrusion amount, material specific heat capacity, material extrusion temperature and current cavity temperature, and the future heat input of the drive component is obtained based on the corresponding printing path movement speed, acceleration and execution time.

[0111] The future heat input of the nozzle, the future heat input of the heated bed, the future heat input of the deposited material, and the future heat input of the drive components for each prediction period are summed to obtain the future additional heat load for the corresponding prediction period, and then arranged into a sequence of future additional heat loads in chronological order.

[0112] The current operating radiator and its corresponding heat dissipation level are determined based on the current radiator operating status. The baseline estimated heat dissipation for each prediction period is obtained based on the temperature difference between the cavity temperature data and the ambient temperature data, the passive heat dissipation parameters, and the heat dissipation parameters per unit time corresponding to the current operating radiator. The baseline estimated heat dissipation sequence is then formed according to the time sequence.

[0113] In this embodiment, before performing heat load prediction, the prediction time domain is first discretized. Starting from the current moment, the total prediction time domain is evenly divided into multiple consecutive prediction periods of equal length. The total number of periods and the step size per period can be set according to the controller's computing power and prediction accuracy requirements. The step size per period is typically set to the order of several seconds to tens of seconds, balancing computational efficiency and prediction resolution. After completing the time domain division, the expected start and end times of each printing instruction are calculated segment by segment, based on the printer's kinematic parameters and unexecuted path instructions, and then assigned to the corresponding prediction period. For instructions executed across time periods, parameters such as extrusion volume and runtime can be split according to the execution duration ratio, realizing the mapping from the spatial dimension of the printing path to the temporal dimension of the prediction sequence, providing a task basis for time-by-time heat load calculation.

[0114] Furthermore, the future increase in heat load is calculated separately for each of the four types of heat sources: nozzles, heated beds, deposited materials, and drive components, for each time period. Among these, nozzles are electric power heating heat sources, and the formula for calculating their future heat input per time period is as follows:

[0115] ;

[0116] In the formula, For the first Total future heat input to the nozzles within a predicted time period; For the first The historical heating duty cycle of the nozzle within a prediction period is dimensionless and ranges from [0,1]. The rated heating power of the nozzle, in watts (W), is a fixed hardware parameter. This represents the duration of a single prediction period. The heating duty cycle is obtained using historical matching logic. Specifically, based on the printhead set temperature and ambient temperature for the corresponding period, the steady-state heating duty cycle under the same operating conditions is matched from the printer's operation log. Since the duty cycle fluctuation is small when the printhead PID temperature control is in a steady state, using this as the prediction value provides sufficient engineering accuracy. The calculation method for the future heat input of the heated bed is completely consistent with that of the printhead; only the printhead rated power and printhead heating duty cycle need to be replaced with the corresponding rated power and heating duty cycle parameters of the heated bed.

[0117] The heat input of the deposited material is a sensible heat transfer type heat source, and its future heat input in a single time period is calculated using the following formula:

[0118] ;

[0119] In the formula, For the first The total future heat input brought in by the deposited material within a predicted time period; This represents the expected material extrusion quality for the corresponding time period; The specific heat capacity under constant pressure of the printing material is retrieved from a pre-stored parameter library; This is the material extrusion temperature, which should be consistent with the nozzle setting temperature. This represents the current temperature inside the cavity.

[0120] The future heat input of the drive components also follows the basic calculation logic of power multiplied by duration, and further distinguishes between two operating conditions: constant speed operation and acceleration / deceleration operation. The corresponding operating power and operating duration are matched respectively, and finally multiplied by the heat conversion parameters of the drive components to obtain the effective heat input, so as to match the actual heat generation characteristics of the motor.

[0121] After completing the itemized calculations for the four types of heat sources, the heat input of each type of heat source within the same forecast period is summed to obtain the total future additional heat load for the corresponding period. The calculation formula is as follows:

[0122] ;

[0123] In the formula, For the first The total future heat load for each forecast period is calculated, with the remaining items corresponding to the heat input of the printhead, heated bed, deposition material, and drive components for each period. Arranging the total future heat load for all forecast periods in chronological order forms a complete sequence of future heat loads, representing the total heat injected into the printer during each future period when the printing task is executed as planned.

[0124] The baseline estimated heat dissipation sequence is used to characterize the total heat that can be dissipated from the printer in future time periods while maintaining the current radiator operation status, serving as a benchmark before the adjustment of the cooling strategy. The printer's total heat dissipation capacity consists of two parts: passive cooling and active cooling. Passive cooling is achieved through natural convection and thermal radiation from the device casing, gaps, and top plate, and the heat dissipation power is proportional to the temperature difference between the inside and outside of the cavity. Active cooling is achieved by the currently operating radiator through forced convection, and the heat dissipation power is related to the number of operating radiators and the current cooling level. The formula for calculating the baseline estimated heat dissipation for a single time period is:

[0125] ;

[0126] In the formula, For the first The baseline estimated heat dissipation for the forecast period; The passive heat dissipation coefficient of the printer, in W / ℃, represents the power of passive heat dissipation per unit temperature difference. It is determined by the printer's structure, material, and ventilation gap area, and is a pre-stored calibration parameter. This represents the current temperature inside the cavity. The greater the difference between the internal temperature and the ambient temperature, the higher the passive heat dissipation power. This is the set of indices of the heat sinks that are currently in operation. For the first The heat dissipation parameters of the radiator under the current level represent the heat that the radiator can dissipate per second. The duration of a single forecast period.

[0127] Since the temperature difference between the inside and outside of the cavity fluctuates relatively little in the short prediction time domain, and assuming that the heat dissipation operation status is not adjusted, the baseline heat dissipation for each period can be approximated as a constant value. Arranging the baseline expected heat dissipation for each period in chronological order yields the baseline expected heat dissipation sequence.

[0128] S4. Accumulate the historical unreleased heat storage and the future new heat load sequence according to the predicted time period, and subtract the baseline expected heat release sequence to obtain the rolling heat release sequence; obtain the allowable heat release limit based on the upper limit of the safe temperature inside the cavity, the temperature data inside the cavity and the equivalent heat capacity inside the printer, and determine the predicted time of exceeding the limit.

[0129] This step quantifies the state of excess heat in the cavity at the end of each prediction period through rolling cumulative heat balance calculation, and combines the temperature safety constraints of the printing material to complete the conversion from temperature threshold to heat threshold. Finally, it locates the predicted moment when the heat in the cavity exceeds the safety constraints, providing a time reference for calculating the early triggering time of heat dissipation.

[0130] In one embodiment, step S4 specifically includes: for each forecast period, summing the future additional heat load corresponding to the forecast period and all previous forecast periods to obtain the cumulative amount of future additional heat load.

[0131] For each forecast period, the baseline estimated heat release is accumulated by adding the baseline estimated heat release for that forecast period and all previous forecast periods.

[0132] The historical unreleased heat storage is added to the cumulative amount of future new heat load corresponding to each forecast period, and the corresponding baseline estimated cumulative amount of heat that can be discharged is subtracted to obtain the rolling heat to be discharged for the corresponding forecast period. The rolling heat to be discharged is arranged in chronological order to obtain the rolling heat to be discharged sequence.

[0133] Calculate the temperature difference between the upper limit of the safe temperature inside the cavity and the current temperature inside the cavity, and determine the heat corresponding to the temperature difference and the equivalent heat capacity inside the printer as the upper limit of the allowable heat to be discharged.

[0134] The rolling heat to be discharged is compared with the upper limit of the allowable heat to be discharged in chronological order. The end time of the prediction period corresponding to the first rolling heat to be discharged that reaches the upper limit of the allowable heat to be discharged is determined as the predicted time of exceeding the limit.

[0135] The printer's internal equivalent heat capacity is pre-generated based on the known cumulative printing heat input and the corresponding increase in internal temperature during the period when the radiator is not running.

[0136] In this embodiment, because the heat inside the printer has a cumulative transfer characteristic, the total heat load inside the cavity does not exist independently in a single time period, but is the sum of historical stock and incremental loads in each time period. Therefore, it is necessary to accumulate the future heat input and heat dissipation separately in chronological order to accurately reflect the overall thermal state at each moment. For the future heat input increment, the cumulative amount of the future additional heat load for the first k predicted time periods is calculated using the following formula:

[0137] ;

[0138] In the formula, is the cumulative amount of future new heat load at the end of the k-th prediction period, in J; k is the prediction period index, ranging from 1 to the total number of prediction periods N contained in the prediction time domain, dimensionless; p is the dummy variable for the summation operation, dimensionless. This represents the future additional heat load for the p-th predicted time period, expressed in J, and is taken from the future additional heat load sequence generated in step S3. This cumulative amount represents the total amount of heat injected into the cavity during the printing process from the current time to the end of the k-th time period.

[0139] Corresponding to the cumulative logic on the heat input side, the heat dissipation side also accumulates over time to obtain the cumulative heat dissipation capacity to maintain the current heat dissipation state. The baseline estimated cumulative heat dissipation for the first k prediction periods is calculated using the following formula:

[0140] ;

[0141] In the formula, The baseline estimated cumulative heat release at the end of the k-th forecast period is expressed in J. The baseline estimated heat dissipation for the p-th prediction period is expressed in J, taken from the baseline estimated heat dissipation sequence generated in step S3. This cumulative amount represents the total heat that can be dissipated from the cavity from the current time to the end of the k-th period without adjusting the current heat dissipation strategy, through the combined effects of passive and active heat dissipation.

[0142] Based on the two cumulative amounts and combined with the initial historical unreleased heat storage, the rolling heat to be discharged for each period can be calculated using the heat balance relationship. The rolling heat to be discharged at the end of the k-th prediction period is calculated using the following formula:

[0143] ;

[0144] In the formula, The rolling heat to be discharged at the end of the k-th prediction period, in J; This represents the total unreleased heat storage from all sources at the current moment, expressed in J, and is derived from the calculation results of step S2, serving as the initial heat baseline for the entire prediction cycle. The rolling heat to be discharged characterizes the total surplus heat remaining in all heat storage carriers and air within the printer cavity until the end of the k-th time period, while maintaining the current heat dissipation state. This value simultaneously covers both sensible heat from the air and latent heat storage in the structure, comprehensively reflecting the true thermal load state of the cavity and compensating for the lag in judging the thermal state solely based on air temperature.

[0145] By arranging the rolling heat to be discharged for all prediction periods in chronological order, a rolling heat to be discharged sequence can be obtained. As the printing process progresses, the prediction time domain will be shifted forward by period, and the sequence will be recalculated for each prediction cycle, so as to realize the rolling update and continuous monitoring of the thermal state.

[0146] To achieve a direct comparison between thermal state and safety constraints, the temperature safety threshold corresponding to the printing material needs to be converted into a heat threshold, i.e., the upper limit of the allowable heat to be dissipated. This conversion process is based on the lumped heat capacity model. The upper limit of the allowable heat to be dissipated is calculated using the following formula:

[0147] ;

[0148] In the formula, The upper limit of the allowable heat to be dissipated is expressed in J. The equivalent heat capacity inside the printer is expressed in J / ℃. It is a pre-stored calibration parameter that treats all heat storage components inside the printer as a single homogeneous heat capacity, representing the total heat absorbed by the entire thermal system to increase its temperature by 1℃. This is the upper limit of the safe temperature inside the cavity corresponding to the current printing material, in °C. It is retrieved from the pre-stored parameter library by the printing material identifier. Exceeding this temperature will cause the deposited material to soften and deform, affecting the printing quality. The current air temperature inside the cavity is expressed in °C and is taken from the temperature acquisition data in step S1.

[0149] The maximum allowable heat to be dissipated represents the maximum amount of excess heat that the entire printer's thermal system can hold, based on the current cavity temperature. Once the rolling heat to be dissipated exceeds this maximum, the cavity temperature will exceed the material's corresponding safe temperature threshold. The printer's internal equivalent heat capacity is generated through pre-calibration. During a period when the radiator is not running and other operating conditions are stable, the cumulative amount of printing heat input and the corresponding increase in cavity temperature are recorded. This data is then fitted using a heat balance relationship. This calibration process can be completed before shipment or iteratively updated online during printing to ensure the accuracy of temperature and heat conversion.

[0150] After obtaining the rolling heat release sequence and the allowable heat release upper limit, the first heat exceeding the limit is located by comparing them sequentially across time periods. The controller first iterates through the rolling heat release sequence in chronological order, selecting the first predicted time period where the heat release is greater than or equal to the allowable upper limit. This time period is recorded as the first exceeding limit time period, and its corresponding index is recorded as the first exceeding limit time period index. Based on this index, the predicted exceeding limit time can be calculated using the following formula:

[0151] ;

[0152] In the formula, The unit for predicting the time of exceeding the limit is seconds; The current time is expressed in seconds (s). This is an index of the prediction period corresponding to the first time the limit is exceeded; it is dimensionless. The duration of a single prediction period is expressed in seconds. The predicted limit-breaking moment represents the moment when, under the condition of maintaining the current heat dissipation state, the total heat inside the printer will exceed the safety threshold, and the cavity temperature will reach the upper limit of the safe temperature of the corresponding material. This moment is the time reference for calculating the early triggering time of the heat sink.

[0153] It should be noted that the controller is configured with corresponding processing logic for boundary conditions during the prediction process. If, after traversing all prediction periods within the prediction time domain, the rolling heat to be dissipated is consistently below the allowable upper limit, it is determined that there is no risk of exceeding the limit within the current prediction time domain. The controller will maintain the current radiator operating state, roll the prediction time domain forward by one prediction period, and then re-execute the complete calculation process from steps S1 to S6. If the rolling heat to be dissipated in the first prediction period exceeds the allowable upper limit, it is determined that the current state is approaching or already in an over-limit condition. The controller will immediately trigger the corresponding level of cooling operation to prevent the cavity temperature from continuously rising.

[0154] S5. Based on the current printed part geometry data and the heat dissipation response parameters corresponding to each candidate heat dissipation level, obtain the comprehensive heat dissipation activation delay amount, advance the predicted over-limit time corresponding to the comprehensive heat dissipation activation delay amount, and obtain the candidate early trigger time.

[0155] Step S5 follows from the predicted over-limit moment output in step S4. For different candidate heat dissipation levels, it quantifies the end-to-end delay from the output of the start command to the effective decrease in cavity temperature. It corrects for airflow lag based on the current geometric conditions of the printed part and adds a safety compensation margin, ultimately outputting the candidate early trigger moment for each candidate heat dissipation level. This step addresses the shortcomings of existing technologies that use a fixed early start time and cannot adapt to fluctuations in heat dissipation delay caused by changes in the height and cross-section of the printed part, achieving adaptive matching of heat dissipation trigger timing based on operating conditions.

[0156] In one embodiment, step S5 includes setting multiple candidate heat dissipation levels from low to high according to the heat sink drive duty cycle.

[0157] For each candidate heat dissipation level, obtain the radiator start-up delay and airflow establishment delay from the corresponding heat dissipation response parameters.

[0158] The airflow transfer delay is obtained based on the distance between the current printing area and the corresponding heat sink, the current printing height, the area ratio between the current layer's projected area and the printer's internal cross-sectional area, and the airflow velocity parameters of the corresponding candidate heat dissipation level.

[0159] Extract historical heat dissipation response records from historical heat dissipation response records. The candidate heat dissipation level, the temperature difference range inside and outside the cavity, and the height range of the printed part all match the current state. The temperature response delay is obtained based on the historical heat dissipation response records.

[0160] The total effective delay of heat dissipation for the corresponding candidate heat dissipation level is obtained by summing the heat sink start-up delay, airflow establishment delay, airflow transfer delay, and temperature response delay.

[0161] Based on the positive time deviation between the historical predicted over-limit time and the corresponding actual over-limit time, a safety compensation duration is generated. The predicted over-limit time is then combined with the heat dissipation activation delay and the safety compensation duration to obtain the candidate early trigger time for the corresponding candidate heat dissipation level.

[0162] In this embodiment, the controller pre-sets multiple discrete candidate heat dissipation levels according to the heat sink drive duty cycle from low to high. Each level corresponds to a different target fan speed, heat dissipation capacity per unit time, and heat dissipation response parameters. The performance parameters corresponding to all levels are pre-stored in the controller's parameter library by level index and can be directly retrieved. The purpose of setting multiple candidate levels is to provide a set of alternatives for subsequent heat dissipation decisions, so as to prioritize the operation of the lowest heat dissipation level while ensuring that the cavity temperature does not exceed the safety limit, thereby achieving the optimization goals of energy saving and noise reduction.

[0163] The process of heat dissipation from command output to temperature activation is a sequential physical process. It primarily involves two inherent system response delays: radiator startup delay and airflow establishment delay. Both can be directly retrieved from a pre-stored heat dissipation response parameter library according to the corresponding candidate heat dissipation level. The radiator startup delay refers to the time required from the controller outputting the startup command to the fan rotor reaching the target speed and outputting rated air pressure. Higher heat dissipation levels correspond to higher target speeds and longer motor acceleration strokes, typically resulting in a slightly increased startup delay. The airflow establishment delay refers to the time required for the printer cavity to transition from the original natural flow field to a stable forced convection flow field after the fan reaches the target speed. Higher heat dissipation levels result in larger fan airflow, faster flow field reconstruction within the cavity, and correspondingly smaller airflow establishment delay.

[0164] In addition to the above, the heat dissipation process also involves airflow transmission delay. This delay characterizes the time it takes for a stable cooling airflow to travel from the radiator outlet to the core printing area. It is significantly affected by the obstruction effect of the printed part's geometry and is a core delay term that dynamically changes with the printing process. The formula for calculating this delay is: ;

[0165] In the formula, For the first The airflow delivery delay corresponding to the stage of heat dissipation, in seconds; The average distance from all heat sinks to the current printing area is in meters. It is calculated by taking the average of the straight-line distances from the center of each heat sink vent to the geometric center of the current printing area. The greater the distance, the longer the airflow transmission time. For the first The airflow velocity parameter corresponding to the heat dissipation level is expressed in meters per second. It corresponds to the nominal airflow velocity at the outlet of the radiator at that level. The higher the heat dissipation level, the greater the airflow velocity and the smaller the transmission delay. The correction coefficient for the obstruction of airflow by the printed part is a dimensionless calibration parameter that characterizes the obstruction strength of the airflow by the printed part. It is obtained by pre-calibration based on the cavity structure and flow field characteristics. This is the current print height of the document, in meters. The maximum printable height of the printer is in meters, and the ratio of the two is the percentage of the height of the printed part. The projected area of ​​the current printed layer, in meters. 2 , The cross-sectional area of ​​the printer's internal cavity, in meters (m). 2 The ratio of the two is the area percentage of the printed part.

[0166] The first half of the formula Corresponding to the ideal airflow transmission time under unobstructed conditions, the latter half corrects the obstruction effect of the printed part by multiplying the height ratio and the area ratio. The higher the height of the printed part and the larger the projected area, the stronger the obstruction effect on the airflow and the longer the actual transmission time. This achieves dynamic adaptation of the delay amount under different printing conditions.

[0167] The final delay in the heat dissipation effect chain is the temperature response delay, which characterizes the lag time between the arrival of the cooling airflow in the printing area, the completion of heat exchange between the air inside the cavity and the cavity walls, the printed parts, and other heat storage structures, until a noticeable and effective temperature drop occurs inside the cavity. This delay is caused by the inherent inertia of the printer's thermal system. This parameter is obtained by matching historical heat dissipation response records. When filtering historical records, the following matching conditions must be met simultaneously: the heat dissipation level is consistent with the current candidate level, the temperature difference between the inside and outside of the cavity is within the adjacent range of the current temperature difference, and the height of the printed parts is within the adjacent range of the current height. Finally, the average value of the temperature response delay in all matching records is taken as the temperature response delay for the corresponding heat dissipation level under the current operating conditions. Generally, the larger the temperature difference between the inside and outside of the cavity, the higher the heat exchange intensity and the faster the temperature response speed; the larger the heat storage volume, the slower the temperature response. By matching operating conditions, the differences in thermal inertia at different printing stages can be adapted.

[0168] The overall cooling effectiveness delay for the corresponding candidate cooling level is obtained by summing the heatsink start-up delay, airflow establishment delay, airflow transfer delay, and temperature response delay. Since the four delay stages occur sequentially in series, the total delay is the algebraic sum of the individual delays:

[0169] ;

[0170] In the formula, For the first The overall cooling activation delay corresponding to the cooling level, in seconds; For the first The corresponding heatsink startup delay for a high-level cooling system. For the first The airflow build-up delay corresponding to the stage of heat dissipation For the first The airflow delivery delay corresponding to the stage of heat dissipation. For the first The temperature response delay corresponding to each stage of heat dissipation is measured in seconds. The overall heat dissipation activation delay represents the total time required from the moment the controller outputs the heat dissipation start command to the moment an observable and effective drop in the cavity temperature occurs. It is the core bridge connecting the command output moment and the temperature activation moment, and also the core basis for determining the early triggering time of the heat sink.

[0171] Because the heat load prediction model has inherent errors and parameter calibration deviations, strictly setting the triggering timing according to the comprehensive heat dissipation activation delay may lead to actual temperature exceeding the limit due to a late prediction. Therefore, a safety compensation period is needed as a positive time margin. The safety compensation period is generated based on historical operating data. The controller statistically analyzes the positive time deviation of all predicted limit exceeding times that are later than the actual limit exceeding times in history, and takes the statistical average or a specified quantile of the deviation as the final safety compensation period to offset the lag risk caused by prediction errors and ensure that the heat dissipation activation time is earlier than the actual limit exceeding time.

[0172] After obtaining the predicted over-limit time, the overall heat dissipation activation delay, and the safety compensation duration, the candidate early trigger time for the corresponding candidate heat dissipation level can be obtained by working backward from the predicted over-limit time to calculate the overall delay and safety compensation duration. The calculation formula is as follows:

[0173] ;

[0174] In the formula, For the first The candidate advance trigger time corresponding to the cooling level, in seconds, is the target time when the controller should output the cooling start command for that level. The predicted time of exceeding the limit is calculated in step S4, in seconds; For the first The overall cooling activation delay corresponding to the cooling level, in seconds; For safety compensation duration, the unit is seconds. It should be noted that there are differences in the overall activation delay and heat dissipation capacity of different heat dissipation levels. Therefore, for different candidate trigger times, generally, higher-level heat dissipation has stronger heat dissipation capacity and a relatively shorter overall delay, so the trigger time can be relatively delayed; lower-level heat dissipation has weaker heat dissipation capacity and a relatively longer overall delay, so it needs to be triggered earlier.

[0175] S6. Generate a candidate rolling heat dissipation sequence based on each candidate early trigger time and the corresponding candidate heat dissipation level. Determine the lowest candidate heat dissipation level in the prediction time domain where none of the rolling heat dissipation levels have reached the upper limit of the allowable heat dissipation level. Determine the corresponding candidate early trigger time as the target early trigger time. Control the operation of the radiator according to the target early trigger time and the target heat dissipation level.

[0176] This step is used to select the lowest target heat dissipation level and the corresponding target advance trigger time under the constraint that the rolling heat to be dissipated is always below the safety limit throughout the entire prediction time domain, and output control commands to drive the heat sink to run, so as to ensure that the temperature inside the printing cavity does not exceed the material safety threshold while taking into account the energy-saving and noise-reducing operation of the heat dissipation system.

[0177] In one embodiment, step S6 includes: for each candidate heat dissipation level, replacing the baseline estimated heat dissipation heat after the corresponding candidate early trigger time with the candidate estimated heat dissipation heat corresponding to the candidate heat dissipation level, and regenerating the candidate rolling heat dissipation heat sequence.

[0178] According to the candidate heat dissipation levels in ascending order, the first candidate heat dissipation level that makes all rolling heat to be dissipated in the prediction time domain lower than the upper limit of the allowable heat to be dissipated is determined as the target heat dissipation level, and the corresponding candidate early trigger time is determined as the target early trigger time.

[0179] In this embodiment, for each candidate heat dissipation level, the full-time heat accumulation process after the level is activated must be simulated first to generate a corresponding candidate rolling heat dissipation sequence, which serves as the basis for subsequent safety verification. Since the prediction time domain is divided into equal-length discrete time periods, the candidate advance trigger times in the continuous time dimension must first be mapped to the corresponding prediction time period index to determine the starting time period for heat dissipation replacement. The calculation formula for the trigger time period index is:

[0180] ;

[0181] In the formula, For the first The trigger start time index corresponding to the stage of heat dissipation is dimensionless, i.e., starting from the [number]th stage. Starting from a certain time period, the heat output will be replaced with the rated heat output of the corresponding level; For the first Candidate early triggering times corresponding to staged heat dissipation; The current moment; The duration of a single forecast period; The calculation is rounded up. Rounding up ensures that the entire time period during which the triggering occurs is calculated based on the upgraded heat dissipation capacity, preserving a safety margin and preventing the heat dissipation capacity from being overestimated due to partial triggering within the time period.

[0182] After determining the trigger start time period, the candidate estimated heat dissipation capacity is calculated using a segmented rule: before the trigger time period, the heat dissipation status remains unchanged, and the original baseline estimated heat dissipation capacity is maintained; during and after the trigger time period, all radiators operate up to the specified time. The target level is achieved, with active heat dissipation capacity increased to the rated level for that level. The formula for calculating the candidate estimated heat release for each prediction period is as follows:

[0183] ;

[0184] In the formula, For the first Level 1 heat dissipation The candidate projected heat release for each forecast period; For the first The baseline estimated heat dissipation for each forecast period is based on the calculation results from step S3. The passive heat dissipation coefficient of the printer represents the power of passive heat dissipation per unit temperature difference and is a pre-stored calibration parameter. This represents the current temperature inside the cavity. The current ambient temperature; This represents the total number of radiators; For a single radiator in the first The heat dissipation parameter per unit time under the heat dissipation level is a pre-stored performance parameter; the higher the level, the larger this value. The duration of a single forecast period.

[0185] Based on the segmented candidate estimated heat release, the cumulative candidate heat release for each time period is obtained by rolling accumulation in chronological order. The calculation method is the sum of the baseline cumulative heat release before triggering and the cumulative heat release of the candidate level after triggering. Based on this, combined with the historical unreleased heat storage obtained in step S2 and the cumulative amount of future new heat load obtained in step S4, the candidate rolling heat release for each time period is calculated through the heat balance relationship. The calculation formula is as follows:

[0186] ;

[0187] In the formula, For the first Level 1 heat dissipation Candidate rolling heat to be discharged at the end of each forecast period; This represents the total unreleased stored heat throughout history, serving as the initial heat baseline for the current moment. To reach the first The cumulative amount of new heat load at the end of each time period is determined by the printing task and is not affected by the heat dissipation strategy. Therefore, the calculation result of step S4 is used directly. For the first Level 1 heat dissipation down to the first The cumulative heat dissipation of candidates at the end of each time period.

[0188] By arranging the candidate rolling heat to be discharged for all prediction periods in chronological order, the candidate rolling heat to be discharged sequence for the corresponding candidate heat dissipation level can be obtained, which fully reflects the heat accumulation trend of the entire prediction time domain after the heat dissipation of that level is started.

[0189] After completing the heat dissipation sequence extrapolation for all candidate levels, target levels are selected based on the principle of prioritizing the lowest energy-saving level. For any candidate heat dissipation level, the criterion for meeting the heat dissipation safety constraints is: the peak value of the candidate rolling heat dissipation in all time periods within the predicted time domain is strictly less than the upper limit of the allowable heat dissipation, mathematically expressed as:

[0190] ;

[0191] In the formula, For the first Predict the peak value of the rolling heat to be dissipated in the time domain under the level of heat dissipation; The upper limit of the allowable heat to be discharged is calculated by step S4 based on the upper limit of the safe temperature inside the cavity and the equivalent heat capacity.

[0192] If the inequality is true, it means that after activating this level of cooling, the total excess heat inside the printer will not exceed the safety threshold throughout the entire prediction period, and this level is a feasible cooling level.

[0193] The selection of the target heat dissipation level follows the rule of verifying from low to high, with the first level to meet the conditions being the optimal one. Safety constraints are verified one by one in order of heat dissipation level from low to high (g=1 to g=G), and the lowest level that first satisfies the condition of not exceeding limits in the entire time domain is determined as the target heat dissipation level. The calculation formula is:

[0194] ;

[0195] In the formula, The final target heat dissipation level is dimensionless; This indicates that the minimum level index that satisfies the constraints is selected.

[0196] It should be noted that a lower heat dissipation level corresponds to a lower fan speed, less operating energy consumption and noise. By adopting a decision logic that prioritizes the lowest level, this invention can minimize overcooling and energy waste while ensuring temperature safety, thus achieving a balance between heat dissipation performance and operating economy.

[0197] The candidate early trigger time corresponding to the target heat dissipation level is the final target early trigger time. For the two extreme boundary scenarios, this invention sets corresponding adaptation rules. Specifically, if after traversing all candidate heat dissipation levels, the requirement that the heat to be dissipated throughout the entire time domain is below the safe upper limit cannot be met, then the highest heat dissipation level is directly selected as the target level to maximize the system's heat dissipation capacity and delay the time when the cavity temperature exceeds the limit as much as possible. If the calculated target early trigger time is earlier than or equal to the current time, it indicates that the current cavity heat load is approaching the limit state. Without waiting for timed triggering, the current time is directly used as the target trigger time, and the radiator is immediately controlled to start operation according to the target heat dissipation level.

[0198] In this invention, after the target heat dissipation level and trigger time are determined, the controller sets a corresponding timed task according to the trigger time, and outputs a heat dissipation start command when the specified time is reached. During the waiting period for triggering, the prediction time domain will roll forward period by period with the printing process. After each prediction period, the controller will re-execute the complete calculation process of steps S1 to S6, and dynamically correct the heat dissipation strategy based on the latest printing progress, temperature data and operating status, forming a rolling optimization closed-loop control mechanism to ensure that the heat dissipation decision is always accurately adapted to the current printing conditions.

[0199] In one embodiment, the present invention further includes: when the rolling heat to be discharged sequence does not reach the upper limit of the allowable heat to be discharged within the prediction time domain, maintaining the current radiator operating state, shifting the prediction time domain backward by one prediction period, and re-executing steps S1 to S6.

[0200] When the target's early trigger time is earlier than or equal to the current time, the current time is determined as the target's early trigger time, and the radiator is controlled to operate according to the target's heat dissipation level.

[0201] After the radiator operates according to the target heat dissipation level, the system continuously acquires the radiator start-up command output time, cavity temperature data, and print heat input data during the heat dissipation period.

[0202] The first sampling moment in which the cavity temperature decreases for three consecutive sampling cycles after the radiator start command is output, and the cumulative decrease is greater than the temperature sensor resolution, is determined as the actual heat dissipation effective moment. The actual heat dissipation effective delay is obtained based on the time interval between the radiator start command output moment and the actual heat dissipation effective moment.

[0203] The actual heat dissipation is obtained based on the cumulative heat input during radiator operation, the temperature change inside the cavity between the start and end of heat dissipation, and the equivalent heat capacity inside the printer.

[0204] The actual delay in the effective cooling is added to the fixed-length historical cooling response record of the corresponding candidate cooling level, and the earliest historical cooling response record is deleted. The cooling response parameters of the corresponding candidate cooling level are then regenerated.

[0205] Update the heat dissipation parameters per unit time for the corresponding target heat dissipation level based on the actual heat dissipation, and re-execute steps S3 to S6 based on the updated heat dissipation response parameters and heat dissipation parameters per unit time.

[0206] In this embodiment, when the target early trigger time obtained by the decision in step S6 is earlier than or equal to the current time, it indicates that the printing condition has changed abruptly, or that the risk of temperature exceeding the limit is approaching due to the concentrated release of historical heat. At this time, the controller no longer waits for the theoretical trigger time, but directly determines the current time as the target early trigger time, and immediately outputs control commands to drive the heat sink to operate according to the target heat dissipation level, giving priority to ensuring that the temperature inside the cavity does not exceed the safety threshold, and eliminating the logical contradiction and heat dissipation delay risk caused by the negative waiting time.

[0207] After the radiator starts operating at the target heat dissipation level, the controller continuously collects data from the radiator start command output time, the cavity temperature data for each sampling period, and the printed heat input data during the heat dissipation operation for subsequent parameter self-updates. The actual heat dissipation activation time is determined as follows: starting from the radiator start command output time, when the cavity temperature shows a monotonically decreasing trend for three consecutive sampling periods, and the cumulative temperature decrease is greater than the resolution of the temperature sensor, the first sampling time that meets this condition is determined as the actual heat dissipation activation time. This eliminates interference from sensor measurement noise and ensures the reliability of the activation time determination. Based on the above two times, the actual comprehensive heat dissipation activation delay for this heat dissipation process can be calculated using the following formula:

[0208] ;

[0209] In the formula, This represents the actual overall delay in the effectiveness of heat dissipation during this process, expressed in seconds. The actual time when heat dissipation takes effect is in seconds; This is the output time of the heatsink activation command, in seconds. This actual overall heat dissipation activation delay covers the real time consumption of the entire chain, from hardware startup, flow field establishment, airflow transfer, and temperature response, and can truly reflect the heat dissipation response characteristics under the current geometric state of the printed part and the degree of system aging.

[0210] Based on the principle of energy conservation, the controller can infer the actual total heat dissipation during this heat dissipation process from the changes in cavity temperature and heat input data. The formula for calculating the actual heat dissipation is:

[0211] ;

[0212] In the formula, This represents the actual total heat dissipation during this heat dissipation process, expressed in joules. The cumulative amount of printing heat input injected into the cavity by all heat sources during the heat dissipation operation, expressed in joules. The printer's internal equivalent heat capacity is expressed in joules per degree Celsius. The temperature inside the cavity at the moment heat dissipation begins, in degrees Celsius. This represents the cavity temperature at the end of heat dissipation, expressed in degrees Celsius. According to the law of conservation of energy, the change in the system's internal energy is equal to the difference between the input heat and the dissipated heat. Therefore, the dissipated heat can be obtained by subtracting the change in internal energy from the input heat. When heat dissipation is effective, the cavity temperature decreases, the change in internal energy becomes negative, and the actual dissipated heat will be greater than the heat input during the same period.

[0213] To achieve adaptive iteration of the heat dissipation response parameters, the controller maintains a fixed-length historical heat dissipation response record queue for each candidate heat dissipation level. This invention employs a first-in, first-out (FIFO) sliding window mechanism for data updates. Specifically, upon obtaining a new actual overall heat dissipation activation delay, the controller adds this data to the tail of the historical record queue for the corresponding heat dissipation level. If the queue length exceeds the preset fixed window length, the oldest historical record in the queue is deleted, ensuring that the queue always retains the measured data from the most recent heat dissipation processes. After completing the queue update, the controller regenerates the overall heat dissipation activation delay parameter corresponding to that heat dissipation level, calculated using the following formula:

[0214] ;

[0215] In the formula, For the updated version The overall cooling activation delay corresponding to the cooling level, in seconds; The fixed window length of the historical record queue is a dimensionless integer. For the first The first corresponding to the first level of heat dissipation The historical actual effective delay is measured in seconds. Through this moving average mechanism, the thermal response parameters can continuously adapt to changes in operating conditions such as fan dust accumulation, increased print height, and enhanced airflow obstruction, gradually replacing the factory calibration value and improving the accuracy of subsequent delay predictions.

[0216] Simultaneously, based on the actual total heat dissipation measured in this experiment, the controller synchronously updates the heat dissipation parameters per unit time for the corresponding target heat dissipation level. Specifically, the actual total heat dissipation is divided by the effective running time of this heat dissipation to obtain the actual heat dissipation capacity per unit time under that heat dissipation level, thereby overriding the original pre-stored calibration parameters. This iterative correction mechanism can offset the deviations in heat dissipation performance caused by factors such as fan aging, dust accumulation in the air duct, and changes in ambient air pressure, ensuring the accuracy of subsequent calculations of the expected heat dissipation sequence and avoiding the risk of exceeding temperature limits due to overestimation of heat dissipation capacity.

[0217] After updating the heat dissipation response parameters and heat dissipation parameters per unit time, the controller re-executes the calculation process from steps S3 to S6 based on the latest parameter values, reuses the currently acquired print data and heat storage calculation results, and quickly refreshes the future heat load prediction, heat dissipation simulation and heat dissipation level decision results.

[0218] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A heat dissipation device for a 3D printer, characterized in that, include: A rectangular heat dissipation frame is formed by splicing four L-shaped corner frame units end to end, and the free ends of two adjacent L-shaped corner frame units are connected by straight splicing pieces. Top plate, located on top of the rectangular heat dissipation frame; Multiple radiators, each of the L-shaped corner frame units is provided with a heat dissipation mounting cavity and a heat dissipation port communicating with the heat dissipation mounting cavity, the radiator is installed in the heat dissipation mounting cavity, and the ventilation end of the radiator is opposite to the corresponding heat dissipation port; Temperature detection components are used to collect internal temperature data and ambient temperature data of the 3D printer. The controller, installed in the controller mounting cavity of one of the L-shaped corner frame units, is electrically connected to multiple heat sinks and the temperature detection components, and communicatively connected to the 3D printer control unit. The controller acquires historical printing heat input data, future printing task data, and current printed part geometry data. Based on the historical printing heat input data and the cavity temperature data, it generates historical unreleased heat storage data. Based on the future printing task data, it generates a future new heat load sequence. Based on the ambient temperature data and the heat dissipation level of each heat sink, it generates an expected heat dissipation sequence, thereby generating a rolling heat dissipation sequence and a predicted over-limit time. Based on the current printed part geometry data, it generates a comprehensive heat dissipation activation delay to generate the heat sink's early trigger time and heat dissipation level.

2. The 3D printer heat dissipation device according to claim 1, characterized in that, Each L-shaped corner frame unit includes a first frame side and a second frame side that are perpendicularly connected to each other. The free ends of the first frame side and the second frame side are respectively provided with insertion slots extending along the length direction of the corresponding frame side. The straight splicing component includes a first plug segment and a second plug segment that are connected to each other and extend along the same straight line. The first plug segment is inserted into the plug slot of the free end of one of the L-shaped corner frame units, and the second plug segment is inserted into the plug slot of the free end of another adjacent L-shaped corner frame unit. The free end faces of two adjacent L-shaped corner frame units abut against each other, and the first insertion segment and the second insertion segment are accommodated together in the accommodating space formed by the insertion slots of the two adjacent L-shaped corner frame units.

3. The 3D printer heat dissipation device according to claim 1, characterized in that, The heat dissipation mounting cavity is formed by recessing the outer surface of the corresponding L-shaped corner frame unit inward. The heat dissipation opening penetrates the bottom of the heat dissipation mounting cavity and communicates with the inner space of the rectangular heat dissipation frame. The mounting edge of the heat sink is fixed to the bottom of the heat dissipation mounting cavity by multiple screws. The controller mounting cavity is located in one of the L-shaped corner frame units. The controller is connected to each of the heat sinks via wires to control the start, stop and heat dissipation level of each heat sink. The temperature detection assembly includes at least one internal temperature sensor and at least one ambient temperature sensor. The internal temperature sensor is located on the side of the rectangular heat dissipation frame facing the interior of the 3D printer, and the ambient temperature sensor is located on the side of the rectangular heat dissipation frame or the top plate facing the external environment.

4. A heat dissipation method for a 3D printer, characterized in that, Performed by the controller of the 3D printer's heat dissipation device, including: S1. Obtain historical printing heat input data, future printing task data, cavity temperature data, ambient temperature data, current printed part geometry data, heat storage attenuation parameters, cavity safe temperature limit corresponding to printing material, printer internal equivalent heat capacity, and heat dissipation response parameters corresponding to each candidate heat dissipation level. S2. Generate each historical heat input amount based on the historical printed heat input data, calculate the remaining heat of each historical heat input amount at the current moment using the corresponding heat storage attenuation parameter, and accumulate each remaining heat to obtain the historical unreleased heat storage. S3. Process the future printing task data according to multiple consecutive prediction periods to obtain the future new heat load sequence, and obtain the baseline expected heat dissipation sequence based on the cavity temperature data, the ambient temperature data and the current radiator operating status. S4. Accumulate the historical unreleased heat storage and the future new heat load sequence according to the predicted time period, and subtract the baseline expected heat release sequence to obtain the rolling heat release sequence; obtain the allowable heat release limit based on the cavity safety temperature limit, the cavity temperature data and the printer's internal equivalent heat capacity, and determine the predicted time of exceeding the limit. S5. Based on the current printed part geometry data and the heat dissipation response parameters corresponding to each of the candidate heat dissipation levels, obtain the comprehensive heat dissipation activation delay amount, advance the predicted over-limit time by the corresponding comprehensive heat dissipation activation delay amount, and obtain the candidate early trigger time. S6. Generate a candidate rolling heat dissipation sequence based on each candidate early trigger time and the corresponding candidate heat dissipation level. Determine the lowest candidate heat dissipation level in the prediction time domain where none of the rolling heat dissipation levels have reached the upper limit of the allowable heat dissipation level, determine the corresponding candidate early trigger time as the target early trigger time, and control the radiator operation according to the target early trigger time and the target heat dissipation level.

5. The 3D printer heat dissipation method according to claim 4, characterized in that, Step S1 includes: Read the current printing program, printer operation log, temperature acquisition records, radiator control records, and pre-stored parameter library; The current printing program is parsed to obtain the printing material identifier, executed path instructions, and unexecuted path instructions; The current printed part geometry data is generated based on the executed path instructions. The current printed part geometry data includes the current printing height, the current layer projection area, and the distance between the current printing area and each heat sink. The future print task data is generated based on the unexecuted path instructions. The future print task data includes the subsequent print path, print speed, expected material extrusion amount, nozzle set temperature, heated bed set temperature, and drive component runtime. Extract the historical printing heat input data with heat source identifier and timestamp from the printer operation log, extract the cavity temperature data and the ambient temperature data from the temperature acquisition record, and extract the current radiator operating status from the radiator control record; The upper limit of the safe temperature inside the cavity is obtained from the pre-stored parameter library based on the printing material identifier, and the heat storage attenuation parameter, the equivalent heat capacity inside the printer, and the heat dissipation response parameters corresponding to each of the candidate heat dissipation levels are obtained from the pre-stored parameter library.

6. The 3D printer heat dissipation method according to claim 5, characterized in that, Step S2 includes: Based on the heat source identifier, the historical printing heat input data is divided into nozzle heat input data, heated bed heat input data, deposited material heat input data, and drive component heat input data; Based on the nozzle heating power, nozzle heating duration, and nozzle heat conversion parameters in the nozzle heat input data, the historical heat input of the nozzle is obtained; Based on the heating power, heating duration, and heat conversion parameters of the heated bed in the heated bed heat input data, the historical heat input of the heated bed is obtained; Based on the material extrusion mass, specific heat capacity, extrusion temperature, and cavity temperature at the corresponding moment in the heat input data of the deposited material, the historical heat input of the deposited material is obtained. Based on the driving component operating power, driving component operating duration, and driving component thermal conversion parameters in the driving component thermal input data, the historical thermal input of the driving component is obtained; The end time of the heat input period corresponding to each historical heat input is determined as the generation time of the historical heat input. Based on the time interval from the generation time to the current time and the heat storage attenuation parameter of the corresponding heat source, the remaining heat of each historical heat input at the current time is obtained, and the remaining heat is accumulated to obtain the historical unreleased heat storage. The heat storage attenuation parameter is generated in advance based on the data of the temperature decrease over time during a historical identification period when the heat input of the corresponding heat source decreases or stops, the heat input state of other heat sources remains unchanged, and the radiator operation state remains unchanged.

7. The 3D printer heat dissipation method according to claim 5, characterized in that, Step S3 includes: The prediction time domain is divided into multiple prediction time periods of equal length, and the unexecuted path instructions are assigned to the corresponding prediction time periods according to their execution time. For each predicted time period, based on the corresponding printhead set temperature and ambient temperature, the matching printhead historical heating duty cycle is extracted from the printer operation log, and the future heat input of the printhead is obtained based on the printhead historical heating duty cycle, the printhead rated power and the duration of the predicted time period. Based on the corresponding heated bed set temperature and ambient temperature, the matching historical heating duty cycle of the heated bed is extracted from the printer operation log, and the future heat input of the heated bed is obtained based on the historical heating duty cycle of the heated bed, the rated power of the heated bed, and the duration of the predicted period. The future heat input of the deposited material is obtained based on the corresponding expected material extrusion amount, material specific heat capacity, material extrusion temperature and current cavity temperature, and the future heat input of the drive component is obtained based on the corresponding printing path movement speed, acceleration and execution time. The future heat input of the nozzle, the future heat input of the heated bed, the future heat input of the deposited material and the future heat input of the drive component for each prediction period are summed to obtain the future additional heat load for the corresponding prediction period, and the future additional heat load sequence is formed in chronological order. The current operating radiator and its corresponding heat dissipation level are determined based on the current radiator operating status. The baseline estimated heat dissipation for each predicted period is obtained based on the temperature difference between the cavity temperature data and the ambient temperature data, the passive heat dissipation parameters, and the heat dissipation parameters per unit time corresponding to the current operating radiator. The baseline estimated heat dissipation sequence is then formed in chronological order.

8. The 3D printer heat dissipation method according to claim 4, characterized in that, Step S4 includes: For each forecast period, the future additional heat load corresponding to that forecast period and all previous forecast periods is added together to obtain the cumulative amount of future additional heat load. For each forecast period, the baseline estimated heat release is accumulated by adding the baseline estimated heat release for that forecast period and all previous forecast periods. The historical unreleased heat storage is added to the cumulative amount of future new heat load corresponding to each predicted period, and the corresponding baseline estimated heat discharge cumulative amount is subtracted to obtain the rolling heat to be discharged for the corresponding predicted period. The rolling heat to be discharged is arranged in chronological order to obtain the rolling heat to be discharged sequence. Calculate the temperature difference between the upper limit of the safe temperature inside the cavity and the current temperature inside the cavity, and determine the heat corresponding to the temperature difference and the equivalent heat capacity inside the printer as the upper limit of the allowable heat to be discharged. The rolling heat to be discharged is compared with the upper limit of the allowable heat to be discharged in chronological order, and the end time of the predicted period corresponding to the first rolling heat to be discharged that reaches the upper limit of the allowable heat to be discharged is determined as the predicted time of exceeding the limit. The equivalent heat capacity inside the printer is pre-generated based on the known cumulative printing heat input and the corresponding increase in internal temperature during the period when the radiator is not running.

9. The 3D printer heat dissipation method according to claim 4, characterized in that, Step S5 includes: Multiple candidate heat dissipation levels are set from low to high according to the heat sink drive duty cycle; For each candidate heat dissipation level, the radiator start-up delay and airflow establishment delay are obtained from the corresponding heat dissipation response parameters; The airflow transfer delay is obtained based on the distance between the current printing area and the corresponding heat sink, the current printing height, the area ratio between the current layer projection area and the printer's internal cross-sectional area, and the airflow velocity parameters of the corresponding candidate heat dissipation level. Extract historical heat dissipation response records from historical heat dissipation response records. The candidate heat dissipation level, the temperature difference range inside and outside the cavity, and the height range of the printed part all match the current state. The temperature response delay is obtained based on the historical heat dissipation response records. The heat sink start-up delay, airflow establishment delay, airflow transmission delay, and temperature response delay are summed to obtain the comprehensive heat dissipation activation delay for the corresponding candidate heat dissipation level. Based on the positive time deviation between the historical predicted over-limit time and the corresponding actual over-limit time, a safety compensation duration is generated. The predicted over-limit time is advanced by the comprehensive heat dissipation activation delay and the safety compensation duration to obtain the candidate early trigger time for the corresponding candidate heat dissipation level. Step S6 includes: For each candidate heat dissipation level, the baseline estimated heat dissipation time after the corresponding candidate early trigger time is replaced with the candidate estimated heat dissipation time corresponding to that candidate heat dissipation level, and the candidate rolling heat dissipation sequence is regenerated. According to the candidate heat dissipation levels in ascending order, the first candidate heat dissipation level that makes all rolling heat to be dissipated in the prediction time domain lower than the upper limit of the allowable heat to be dissipated is determined as the target heat dissipation level, and the corresponding candidate early trigger time is determined as the target early trigger time.

10. The 3D printer heat dissipation method according to any one of claims 4-9, characterized in that, Also includes: When the rolling heat to be discharged sequence does not reach the upper limit of the allowable heat to be discharged within the prediction time domain, the current radiator operation status is maintained, the prediction time domain is shifted backward by one prediction period, and steps S1 to S6 are re-executed. When the target's early trigger time is earlier than or equal to the current time, the current time is determined as the target's early trigger time, and the radiator is controlled to operate according to the target's heat dissipation level. After the radiator operates according to the target heat dissipation level, continuously acquire the radiator start command output time, cavity temperature data, and print heat input data during heat dissipation; The first sampling moment in which the cavity temperature decreases for three consecutive sampling cycles and the cumulative decrease is greater than the temperature sensor resolution, starting from the moment the radiator start command is output, is determined as the actual heat dissipation effective moment. The actual heat dissipation effective delay is obtained based on the time interval between the radiator start command output moment and the actual heat dissipation effective moment. The actual heat dissipation is obtained based on the cumulative amount of printing heat input during the operation of the radiator, the change in cavity temperature between the start and end of heat dissipation, and the equivalent heat capacity inside the printer. The actual heat dissipation effective delay is added to the fixed-length historical heat dissipation response record of the corresponding candidate heat dissipation level, and the earliest historical heat dissipation response record is deleted. The heat dissipation response parameters of the corresponding candidate heat dissipation level are then regenerated. Update the unit-time heat dissipation parameters corresponding to the target heat dissipation level based on the actual heat dissipation, and re-execute steps S3 to S6 based on the updated heat dissipation response parameters and the unit-time heat dissipation parameters.

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