Control device and control method of 3D printer, 3D printer and storage medium

Abstract

The invention discloses a control method of a 3D printer, the 3D printer comprises a first switch and a first heating module which are connected in series to form a first branch, and a second switch and a second heating module which are connected in series to form a second branch, and the first branch and the second branch are connected in parallel with a commercial power grid. The heating power of the two heating modules in the temperature rising stage is larger than the heating power of the two heating modules in the temperature maintaining stage. The control method comprises the following steps: when the two heating modules are in a temperature rise stage, respectively sending a first control signal and a second control signal to the first switch and the second switch; after the two heating modules reach respective target temperatures, a third control signal and a fourth control signal are sent to the first switch and the second switch respectively, and the duty ratios of the third control signal and the fourth control signal are smaller than those of the first control signal and the second control signal respectively; the second and fourth control signals are periodic control signals; and in the unit control period, the third control signal controls the on and off moments of the first switch to be different from the fourth control signal controls the on and off moments of the second switch.

Description

Technical Field

[0001] This application relates to the field of 3D printing technology, specifically to a control method for a 3D printer, a control device for a 3D printer, a 3D printer, and a computer-readable storage medium. Background Technology

[0002] During the material heating stage, 3D printers connect their heating modules to a 220V AC mains power supply to rapidly raise their temperature to the target temperature needed to melt the printing material. Once the heating module reaches the target temperature, the printer intermittently switches it on and off at a certain frequency to maintain its temperature within the melt-proof range. Because 3D printers typically have at least two heating modules, and these modules are inherently high-impedance loads, the frequent connection of at least two high-impedance loads to the AC mains can cause severe flickering in the lighting fixtures connected to the same circuit as the printer. This flickering can trigger seizures in individuals with photosensitive epilepsy, significantly impacting the user experience. Summary of the Invention

[0003] In view of the above problems, this application provides a control method for a 3D printer, a control device for a 3D printer, a 3D printer, and a computer-readable storage medium.

[0004] In a first aspect, this application provides a control method for a 3D printer. The 3D printer includes a first switch, a first heating module, a second switch, and a second heating module. The first switch and the first heating module are connected in series to form a first branch, and the second switch and the second heating module are connected in series to form a second branch. The first branch and the second branch are connected in parallel to the mains power grid. The first heating module and the second heating module include a heating stage and a temperature maintenance stage. The heating power required by the first heating module in the heating stage is greater than the heating power required in the temperature maintenance stage, and the heating power required by the second heating module in the heating stage is greater than the heating power required in the temperature maintenance stage. The control method includes: When the first heating module and the second heating module are in the heating stage, a first control signal and a second control signal are sent to the first switch and the second switch respectively. The temperature of the first heating module is obtained. After the temperature of the first heating module reaches the first target temperature, a third control signal is sent to the first switch to put the first heating module into a temperature maintenance phase. The duty cycle of the third control signal is less than that of the first control signal. The temperature of the second heating module is obtained. After the temperature of the second heating module reaches the second target temperature, a fourth control signal is sent to the second switch to put the second heating module into a temperature maintenance phase. The duty cycle of the fourth control signal is less than that of the second control signal. Wherein, the third control signal and the fourth control signal are periodic unit control signals; within the unit control cycle, the moment when the third control signal controls the first switch to turn on is the first moment, and the moment when the third control signal controls the first switch to turn off is the second moment; the moment when the fourth control signal controls the second switch to turn on is the third moment, and the moment when the fourth control signal controls the first switch to turn off is the fourth moment; the first moment is different from the third moment, and the second moment is different from the fourth moment.

[0005] In some embodiments, the 3D printer includes a heated bed heating module, a cavity heating module, and a hot end heating module; the first heating module and the second heating module are any two different heating modules among the heated bed heating module, the cavity heating module, and the hot end heating module.

[0006] In some embodiments, the heating power P12 required for the first heating module to be in the temperature maintenance stage and the heating power P22 required for the second heating module to be in the temperature maintenance stage satisfy the following relationship: 1%≤(P12-P22) / P12≤20%.

[0007] In some implementations, when the sum of the duty cycles of the third control signal and the fourth control signal is equal to 1, the third control signal controls the timing when the first switch is turned on, and the fourth control signal controls the timing when the second switch is turned off; conversely, when the third control signal controls the timing when the first switch is turned off, the fourth control signal controls the timing when the second switch is turned on.

[0008] In some implementations, when the sum of the duty cycles of the third control signal and the fourth control signal is less than 1, the first switch and the second switch are simultaneously in the off state within the unit control cycle.

[0009] In some implementations, when the sum of the duty cycles of the third control signal and the fourth control signal is greater than 1, the first switch and the second switch are simultaneously in the on state within the unit control cycle.

[0010] In some implementations, the unit control cycle comprises a plurality of consecutive small control cycles, each of which comprises three half-waves.

[0011] In some embodiments, the three half-waves in the small control cycle include a first half-wave, a second half-wave, and a third half-wave; when the duty cycle of the third control signal and the fourth control signal is 1 / 3, in each small control cycle of the third control signal, the first half-wave is used to control the first switch to be turned on, and in each small control cycle of the third control signal, the second half-wave and the third half-wave are used to control the first switch to be turned off; in each small control cycle of the fourth control signal, the first half-wave and the second half-wave are used to control the second switch to be turned off, and in each small control cycle of the fourth control signal, the third half-wave is used to control the second switch to be turned on.

[0012] In some embodiments, the three half-waves in the small control cycle include a first half-wave, a second half-wave, and a third half-wave; when the duty cycle of the third control signal and the fourth control signal is 1 / 3, in each small control cycle of the third control signal, the first half-wave is used to control the first switch to be turned on, and in each small control cycle of the third control signal, the second half-wave and the third half-wave are used to control the first switch to be turned off; in each small control cycle of the fourth control signal, the first half-wave and the third half-wave are used to control the second switch to be turned off, and in each small control cycle of the fourth control signal, the second half-wave is used to control the second switch to be turned on.

[0013] Secondly, this application provides a control device for a 3D printer, the 3D printer including a first switch, a first heating module, a second switch, and a second heating module. The first switch and the first heating module are connected in series to form a first branch, and the second switch and the second heating module are connected in series to form a second branch. The first branch and the second branch are connected in parallel to the mains power grid. The first heating module and the second heating module include a heating stage and a temperature maintenance stage. The heating power required for the first heating module in the heating stage is greater than the heating power required in the temperature maintenance stage, and the heating power required for the second heating module in the heating stage is greater than the heating power required in the temperature maintenance stage. The control device includes a sending module and an acquiring module. The sending module is configured to send a first control signal and a second control signal to the first switch and the second switch, respectively, when the first heating module and the second heating module are in the heating stage. The acquiring module is configured to acquire the temperature of the first heating module. The sending module is further configured to send a third control signal to the first switch after the temperature of the first heating module reaches a first target temperature, so that the first heating module is in the temperature maintenance stage, wherein the duty cycle of the third control signal is less than the duty cycle of the first control signal. The acquisition module is further configured to acquire the temperature of the second heating module. The sending module is further configured to: after the temperature of the second heating module reaches the second target temperature, send a fourth control signal to the second switch to put the second heating module into a temperature maintenance phase; the duty cycle of the fourth control signal is less than the duty cycle of the second control signal. The third and fourth control signals are periodic unit control signals; within a unit control cycle, the moment when the third control signal controls the first switch to turn on is the first moment, and the moment when the third control signal controls the first switch to turn off is the second moment; the moment when the fourth control signal controls the second switch to turn on is the third moment, and the moment when the fourth control signal controls the second switch to turn off is the fourth moment; the first moment is different from the third moment, and the second moment is different from the fourth moment.

[0014] Thirdly, this application provides a 3D printer, which includes a memory and a processor. The memory is configured to store a computer program, and the processor, when executing the computer program, implements the control method described in any of the above embodiments.

[0015] Fourthly, this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the control method described in any of the above embodiments.

[0016] In the 3D printer control method, control device, 3D printer, and computer-readable storage medium of this application, during the heating phase of the two heating modules, a first control signal and a second control signal with a relatively large duty cycle are used to control the two heating modules to heat up rapidly, so as to melt the printing material and perform printing in a short time, shortening the waiting time before printing and improving the user experience; moreover, after the two heating modules reach their respective target temperatures, periodic unit control signals (a third control signal and a fourth control signal) with relatively small duty cycles are used to control the two heating modules to enter the temperature maintenance phase, so that the temperature of the heating modules is maintained at a temperature sufficient to melt the printing material. Within a certain range, and by setting the second and fourth control signals to control the conduction time of the first switch and the conduction time of the second switch to be different, as well as the turn-off time of the first switch and the turn-off time of the second switch to be different, this avoids two high-power loads from being connected to and disconnected from the mains power grid at the same time. This time-sharing control strategy disperses the originally concentrated and abrupt power surges to different time points, greatly smoothing the total current drawn from the mains power grid. This effectively suppresses voltage flicker caused by frequent load connection or disconnection, and further suppresses severe flickering of lighting fixtures connected to the same circuit as the 3D printer, eliminating the health threat to photosensitive users and improving user safety and experience.

[0017] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0018] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, wherein: Figure 1 This is a flowchart illustrating the control method of a 3D printer according to some embodiments of this application; Figure 2 This is a three-dimensional structural diagram of a 3D printer according to some embodiments of this application; Figure 3 yes Figure 2 The diagram shows a three-dimensional structural representation of a portion of the 3D printer. Figure 4 yes Figure 2 A schematic diagram of the control device for a 3D printer is shown. Figure 5 yes Figure 2 The diagram shows the connection between the first heating module, the second heating module and the mains power in the 3D printer shown. Figure 6 This is a waveform diagram of the second control signal and the fourth control signal of a 3D printer according to some embodiments of this application; Figure 7 The waveforms of the second control signal and the fourth control signal of the 3D printer according to other embodiments of this application are shown. Figure 8 This is a schematic diagram of the structure of a 3D printer according to some embodiments of this application; Figure 9 This is a schematic diagram of the structure of a 3D printer according to some embodiments of this application; Figure 10 This is a schematic diagram illustrating the connection state of a computer-readable storage medium and a processor according to certain embodiments of this application.

[0019] The reference numerals in the detailed embodiments are as follows: 3D printer 100, first heating module 11, first switch 13, second heating module 21, second switch 23, control device 30, acquisition module 31, transmission module 33, processor 40, memory 50, computer-readable storage medium 200; computer program 202. Detailed Implementation

[0020] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0021] In the description of this application, it should be understood that the terms "center", "length", "upper", "lower", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0022] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0023] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0024] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0025] During the material heating stage, the 3D printer connects the heating module to a 220V AC mains power supply to rapidly raise its temperature to the target temperature needed to melt the printing material. Once the heating module reaches the target temperature, the 3D printer 100 controls the heating module to intermittently switch on and off at a certain frequency to maintain its temperature within the range sufficient to melt the printing material. Since 3D printers typically have at least two heating modules, and these modules are inherently high-impedance loads, the frequent connection of at least two high-impedance loads to the AC mains power supply can lead to severe flickering. This flickering can cause convulsions in individuals with photosensitive epilepsy, significantly impacting the user experience. To address this issue, this application provides a control method for a 3D printer (…). Figure 1 As shown), the control device 30 of the 3D printer 100 ( Figure 4 As shown), 3D printer 100 ( Figure 2 , Figure 8 and Figure 9 (as shown) and computer-readable storage medium 200 ( Figure 10 (As shown).

[0026] Please see Figures 1 to 4In a first aspect, this application provides a control method for a 3D printer. The 3D printer 100 includes a first heating module 11, a first switch 13, a second heating module 21, and a second switch 23. The first switch 13 is connected in series with the first heating module 11 to form a first branch, and the second switch 23 is connected in series with the second heating module 21 to form a second branch. The first branch and the second branch are connected in parallel to the mains power grid. The first heating module 11 and the second heating module 21 include a heating phase and a temperature maintenance phase. The heating power required for the first heating module 11 in the heating phase is greater than the heating power required in the temperature maintenance phase, and the heating power required for the second heating module 21 in the heating phase is greater than the heating power required in the temperature maintenance phase. The control method includes: When the first heating module 11 and the second heating module 21 are in the heating stage, the first control signal and the second control signal are sent to the first switch 13 and the second switch 23 respectively. The temperature of the first heating module 11 is obtained. After the temperature of the first heating module 11 reaches the first target temperature, a third control signal is sent to the first switch 13 to put the first heating module 11 into the temperature maintenance stage. The duty cycle of the third control signal is less than that of the first control signal. The temperature of the second heating module 21 is obtained. After the temperature of the second heating module 21 reaches the second target temperature, a fourth control signal is sent to the second switch 23 to put the second heating module 21 into the temperature maintenance stage. The duty cycle of the fourth control signal is less than that of the second control signal. Among them, the third control signal and the fourth control signal are periodic unit control signals; within the unit control cycle, the moment when the third control signal controls the first switch 13 to turn on is the first moment, and the moment when the third control signal controls the first switch 13 to turn off is the second moment; the moment when the fourth control signal controls the second switch 23 to turn on is the third moment, and the moment when the fourth control signal controls the second switch 23 to turn off is the fourth moment; the first moment is different from the third moment, and the second moment is different from the fourth moment.

[0027] Secondly, this application also provides a control device 30 for a 3D printer 100, which can employ the aforementioned control method for a 3D printer. Specifically, the control device 30 for the 3D printer 100 according to the embodiments of this application includes a sending module 33 and an acquisition module 31. The sending module 33 is configured to send a first control signal and a second control signal to a first switch 13 and a second switch 23 respectively when the first heating module 11 and the second heating module 21 are in the heating stage. The acquisition module 31 is configured to acquire the temperature of the first heating module 11. The sending module 33 is also configured to send a third control signal to the first switch 13 after the temperature of the first heating module 11 reaches a first target temperature, so that the first heating module 11 is in the temperature maintenance stage, wherein the duty cycle of the third control signal is less than the duty cycle of the first control signal. The acquisition module 31 is also configured to acquire the temperature of the second heating module 21. The sending module 33 is also configured to: after the temperature of the second heating module 21 reaches the second target temperature, send a fourth control signal to the second switch 23 to keep the second heating module 21 in a temperature maintenance phase; the duty cycle of the fourth control signal is less than the duty cycle of the second control signal. The third and fourth control signals are periodic unit control signals; within a unit control cycle, the moment when the third control signal controls the first switch 13 to turn on is the first moment, and the moment when the third control signal controls the first switch 13 to turn off is the second moment; the moment when the fourth control signal controls the second switch 23 to turn on is the third moment, and the moment when the fourth control signal controls the second switch 23 to turn off is the fourth moment; the first moment is different from the third moment, and the second moment is different from the fourth moment.

[0028] Specifically, the 3D printer 100 is a rapid prototyping device that constructs three-dimensional solids by depositing materials layer by layer. Specifically, the 3D printer 100 in this embodiment includes a first switch 13, a first heating module 11, a second switch 23, and a second heating module 21.

[0029] The first heating module 11 is the core component of the 3D printer 100 that performs the heating function, and the second heating module 21 is another core component of the 3D printer 100 that performs the heating function. The 3D printer 100 may include a heated bed heating module, a cavity heating module, and a hot end heating module.

[0030] The heated bed module is a heating component used to heat the 3D printer's molding platform (heated bed). It typically employs a flat-panel structure and includes a heating element and a substrate. The substrate can be made of aluminum to ensure temperature uniformity or fiberglass to reduce weight. The heating element can be a heating plate, a carbon nanotube heating film, or a silicone rubber heater, etc. When energized, the heating element converts electrical energy into heat energy, which is then conducted to heat the entire printing platform, preventing the printed model from warping due to cooling and shrinkage, and improving the adhesion of the printed layer.

[0031] The hot-end heating module is a heating component used to melt the printing material. Hot-end heating modules typically have a cylindrical structure, and the heating element can be a ceramic heating core or a resistance wire. Through precise temperature control, the hot-end heating module heats the extruded thermoplastic material (such as PLA and ABS) to a molten state, ensuring that the material can be continuously and stably extruded from the nozzle.

[0032] The cavity heating module is a heating component used to maintain the internal temperature of the 3D printer 100. It typically employs a frame structure, and the heating element can be a ceramic heater or a heating tube. The cavity heating module is installed inside the printer frame and connected to the main control board via high-temperature wires. By heating the air inside the printing cavity, it creates a constant-temperature printing environment, making it particularly suitable for printing engineering plastics such as ABS and PC that are prone to thermal stress cracking.

[0033] The first heating module 11 and the second heating module 21 are any two different heating modules selected from a heated bed heating module, a cavity heating module, and a hot end heating module. In one embodiment, the first heating module 11 is a heated bed heating module, and the second heating module 21 is a hot end heating module. In another embodiment, the first heating module 11 is a hot end heating module, and the second heating module 21 is a cavity heating module. In yet another embodiment, the first heating module 11 is a heated bed heating module, and the second heating module 21 is a cavity heating module.

[0034] The municipal power grid is a public power network that provides standard alternating current (AC) to users. In the embodiments of this application, the municipal power grid is a single-phase AC power grid with an effective voltage of 220V and a frequency of 50Hz.

[0035] Please combine Figure 5 The first switch 13 is a contactless or contact-based switching element that controls the connection and disconnection of the first heating module 11 with the mains power grid. In one embodiment, the first switch 13 is a solid-state relay or a bidirectional thyristor. In another embodiment, the first switch 13 may also be a mechanical relay, an insulated-gate bipolar transistor (IGBT), or a power MOSFET. When a control signal is received from the transmitting module 33 of the main control chip or control device 30, the internal circuit of the first switch 13 is turned on, allowing the mains power to pass through; when the control signal disappears, the internal circuit of the first switch 13 is turned off, cutting off the mains power. The second switch 23 is a switching element that is the same as or of a different type than the first switch 13, used to independently control the connection and disconnection of the second heating module 21 with the mains power grid.

[0036] The first switch 13 is connected in series with the first heating module 11 to form the first branch, and the second switch 23 and the second heating module 21 are connected in series to form the second branch. The first and second branches are connected in parallel to the mains power grid. That is, one end of the first branch and one end of the second branch are connected to the live wire (L) of the mains power grid, and the other end of the first branch and the other end of the second branch are connected to the neutral wire (N) of the mains power grid. This parallel connection ensures that the operating voltage of the two branches is equal, but the current flowing through them can be controlled independently and do not affect each other.

[0037] The heating phase refers to the rapid heating process after the 3D printer 100 is started, during which the heating module quickly rises from the ambient temperature (e.g., 25°C) to the target operating temperature. For example, the hot-end heating module needs to rapidly rise from 25°C to 215°C within 1-2 minutes. During this phase, the heating module needs to overcome its own heat capacity and quickly accumulate heat, therefore it needs to operate at maximum or near-maximum power.

[0038] The temperature maintenance phase refers to the process of maintaining the temperature of the heating module within a target temperature range for an extended period after it reaches the target temperature in order to achieve stable printing. During this phase, only heat loss during the printing process needs to be compensated; therefore, the power required for the temperature maintenance phase is much lower than that required for the heating phase.

[0039] Specifically, the heating power P11 required by the first heating module 11 during the heating phase is greater than the heating power P12 required during the temperature maintenance phase. For example, a hot-end heating module with a rated power of 40W will have a heating power P11 of its rated power of 40W (duty cycle of 100%) during the heating phase, while the heating power P12 during the temperature maintenance phase may only be 10W (duty cycle of 20%). Similarly, the heating power P21 required by the second heating module 21 during the heating phase is greater than the heating power P22 required during the temperature maintenance phase. For example, a heated bed heating module with a rated power of 200W will have a heating power P21 of its rated power of 200W during the heating phase, while the heating power P22 during the temperature maintenance phase may only be 30W.

[0040] The first control signal and the second control signal are drive signals sent by the transmitting module 33 of the main control chip or control device 30 to the first switch 13 and the second switch 23 respectively during the heating stage. The first control signal and the second control signal are PWM signals with a high duty cycle or continuous DC high-level signals, which can keep the switches in a near-always-on state, thereby allowing the heating module to obtain maximum power and achieve rapid heating.

[0041] The third and fourth control signals are drive signals sent by the transmitting module 33 or the main control chip to the first switch 13 and the second switch 23, respectively, during the temperature maintenance phase. The third and fourth control signals are periodic unit control signals; that is, they are continuously and repeatedly output in a fixed time length (i.e., a unit control cycle, e.g., 2 seconds). The duty cycle of the third control signal (e.g., 20%) is less than the duty cycle of the first control signal (100%), and the duty cycle of the fourth control signal (e.g., 20%) is also less than the duty cycle of the second control signal, thereby achieving reduced power operation.

[0042] Within any given control cycle, the first moment (T1-on) when the third control signal turns on the first switch 13 is different from the third moment (T2-on) when the fourth control signal turns on the second switch 23; similarly, the second moment (T1-off) when the third control signal turns off the first switch 13 is also different from the fourth moment (T2-off) when the fourth control signal turns off the second switch 23. This ensures that the switching actions of the first heating module 11 and the second heating module 21 are staggered on the time axis, preventing them from simultaneously connecting and disconnecting from the power grid.

[0043] After the 3D printer 100 is powered on, the transmitting module 33 or the main control chip sends a first and second control signal with relatively high power, causing the two heating modules to heat up rapidly. The acquisition module 31, such as a temperature sensor, monitors the temperature in real time. When either heating module reaches its target temperature, it switches to the temperature maintenance phase. The transmitting module 33 sends a low duty cycle periodic unit control signal (a third control signal and / or a fourth control signal), and through a precise timer, ensures that the on and off times of the third and fourth control signals are staggered within one unit cycle.

[0044] The heated bed heating module, cavity heating module, and hot end heating module differ in their power characteristics. Specifically, the hot end heating module has a lower rated power but requires high temperature control accuracy; the heated bed heating module has a medium rated power and high thermal inertia; and the cavity heating module has a higher rated power. Because these three heating modules have different rated power, the impact on the mains power grid during startup is inherently different. Furthermore, during the maintenance phase, due to their different thermal inertia, the switching frequencies and duty cycles of the three heating modules are completely different. The switching actions of a high-frequency hot end heating module, a low-frequency heated bed heating module, and a cavity heating module that may operate continuously are random and asynchronous. This irregular load change can cause complex and unpredictable voltage flicker in the mains power grid, with a flicker intensity that may far exceed that caused by a single load or two identical loads.

[0045] The control method for the 3D printer and the control device 30 of the 3D printer 100 disclosed in this application utilize a first control signal and a second control signal with a relatively large duty cycle to control the two heating modules to heat up rapidly during the heating phase. This allows the printing material to melt and printing to be performed in a short time, shortening the waiting time before printing and improving the user experience. Furthermore, after the two heating modules reach their respective target temperatures, periodic unit control signals (a third control signal and a fourth control signal) with a relatively small duty cycle are used to control the two heating modules to maintain a temperature in the temperature maintenance phase. This ensures that the temperature of the heating modules is kept within a temperature range sufficient to melt the printing material. The third control signal is also included in this description. The control signal and the fourth control signal control the first switch 13 to turn on at different times and the second switch 23 to turn off at different times. This avoids two high-power loads from being connected to and disconnected from the mains power grid at the same time. This time-sharing control strategy disperses the originally concentrated and abrupt power surges to different time points, greatly smoothing the total current drawn from the mains power grid. This effectively suppresses voltage flicker caused by frequent load connection or disconnection, and further suppresses severe flickering of lighting fixtures connected to the same circuit as the 3D printer 100. This eliminates the health threat to photosensitive users and improves user safety and experience.

[0046] Please see Figure 5 In some embodiments, the heating power P12 required for the first heating module 11 to be in the temperature maintenance stage and the heating power P22 required for the second heating module 21 to be in the temperature maintenance stage satisfy the following relationship: 1%≤(P12-P22) / P12≤20%.

[0047] Heating power P12 refers to the average electrical power required by the first heating module 11 during the temperature maintenance phase to compensate for heat loss. Heating power P22 refers to the average electrical power required by the second heating module 21 during the temperature maintenance phase to compensate for heat loss. These two power values ​​are not fixed but are determined by the target temperature, ambient temperature, material thermal conductivity, and heat dissipation structure. For example, the P12 required to maintain a heated bed at 60°C in a cold environment will be higher than the P12 required to maintain a heated bed at 60°C in a warm environment. Specifically, (P12-P22) / P12 can take any value from 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 1%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, and 20%, or any value between two adjacent values. If (P12-P22) / P12 < 1%, although the time-sharing control effect is better, the higher control accuracy will incur additional costs. If (P12-P22) / P12>20%, that is, one of P12 and P22 is much larger than the other, the total load of the mains power grid will also fluctuate drastically between a high power value and a low power value within a unit control cycle. This makes the time-sharing control strategy no longer have a significant advantage in improving flicker compared to simultaneous on / off control.

[0048] In the control method for the 3D printer and the control device 30 for the 3D printer 100 of this application, 1%≤(P12-P22) / P12≤20% is satisfied, so that the heating power P12 and P22 when the two heating modules are in the temperature maintenance stage are relatively close. In this way, when the time-sharing control strategy is adopted, the total current drawn from the mains power grid can be smoothed to the greatest extent, thereby further suppressing the flickering of the lighting fixtures caused by voltage flicker.

[0049] In some implementations, when the sum of the duty cycles of the third control signal and the fourth control signal is equal to 1, the fourth control signal controls the second switch 23 to turn off when the third control signal controls the first switch 13 to turn on; and the fourth control signal controls the second switch 23 to turn on when the third control signal controls the first switch 13 to turn off.

[0050] Specifically, if the duty cycle of the third control signal is D3 and the duty cycle of the fourth control signal is D4, then the relationship is satisfied: D3 + D4 = 1 (i.e., 100%). For example, when D3 = 30%, D4 = 70%; when D3 = 45%, D4 = 55%.

[0051] The third control signal controls when the first switch 13 is turned on, and the fourth control signal controls when the second switch 23 is turned off. For example, at the same time as the rising edge signal driving the first switch 13 to turn on, the falling edge signal driving the second switch 23 to turn off is also output. This ensures that the second branch is simultaneously disconnected from the mains power grid the instant the first branch is connected. Similarly, the third control signal controls when the first switch 13 is turned off, and the fourth control signal controls when the second switch 23 is turned on, forming the other half-cycle of complementary control. For example, at the same time as the falling edge signal driving the first switch 13 to turn off, the rising edge signal driving the second switch 23 to turn on is also output. This ensures that when the first heating module 11 finishes its current heating cycle, the second heating module 21 can immediately begin its heating task.

[0052] In the control method and control device 30 of the 3D printer 100 of this application, the sum of the duty cycles of the third and fourth control signals is equal to 1, achieving seamless complementary control of the two heating modules. At the instant the first heating module 11 is turned off, the second heating module 21 immediately turns on; and at the instant the first heating module 11 turns on, the second heating module 21 immediately turns off, ensuring that the total load of the mains power grid is never zero or doubled within a unit control cycle, but always maintains a stable load value. This completely eliminates current step changes caused by load connection and disconnection, thereby thoroughly suppressing lighting flicker caused by voltage flicker.

[0053] In some implementations, when the sum of the duty cycles of the third control signal and the fourth control signal is less than 1, the first switch 13 and the second switch 23 may be simultaneously in the off state within a unit control cycle.

[0054] Specifically, D3 + D4 < 1. For example, if D3 = 15% and D4 = 20%, the sum is 35%; or if D3 = 25% and D4 = 30%, the sum is 55%. Thus, a common off-time exists within a unit control cycle. The common off-time refers to a time interval within a unit control cycle T that is neither part of the conduction period of the third control signal nor the conduction period of the fourth control signal. After the first heating module 11 completes its current heating maintenance (first switch 13 is turned off), the second heating module 21 will not immediately begin heating but will wait for a period of time before turning on; similarly, after the second heating module 21 finishes heating, a certain interval is required before the first heating module 11 begins its next heating cycle. Therefore, this duty cycle design is suitable for: operating conditions with high ambient temperatures and slow heat dissipation from the heating modules; operating conditions where the target maintenance temperature required by the printing material is low; and operating conditions where the printer is in a heat preservation standby state. Under these operating conditions, the required sustaining power of both heating modules is low. By setting the sum of their duty cycles to less than 1, the average heating power can be effectively reduced, preventing temperature overshoot.

[0055] In the control method for the 3D printer and the control device 30 of the 3D printer 100 of this application, the sum of the duty cycles of the third control signal and the fourth control signal is less than 1, indicating that within a unit control cycle, there will be a period of time when both the first switch 13 and the second switch 23 are off, which is suitable for operating conditions where the total power required to maintain the temperature is low. Although there is a common off period for the first switch 13 and the second switch 23, since the conduction times are staggered, the connection of the first heating module 11 and the second heating module 21 is still dispersed. Compared with the simultaneous on / off control of the two heating modules with a large duty cycle, the severity of lighting flicker caused by voltage flicker can be reduced.

[0056] In some implementations, when the sum of the duty cycles of the third control signal and the fourth control signal is greater than 1, the first switch 13 and the second switch 23 may be in the on state simultaneously within a unit control cycle.

[0057] Specifically, D3 + D4 > 1. For example, if D3 = 70% and D4 = 50%, the sum is 120%; or if D3 = 60% and D4 = 55%, the sum is 115%. That is, there is an overlapping conduction period within a unit control cycle T—that is, the time interval during which the first switch 13 and the second switch 23 are simultaneously in the conducting state.

[0058] When the fourth control signal turns on the second switch 23, the third control signal turns on the first switch 13 during the time interval before the second switch 23 turns off; or the second switch 23 is turned on before the first switch 13 turns off. In this way, the two heating modules can work in parallel, resulting in power superposition during the overlap period. This duty cycle design is suitable for: conditions where extremely low ambient temperatures lead to rapid heat dissipation, requiring stronger heating power to maintain the temperature; conditions where the printing chamber door is opened and then closed again, requiring rapid restoration of the chamber temperature; conditions where the heated bed needs additional power to compensate for heat dissipation caused by large-area contact when printing large components; and conditions where the hot end requires higher maintenance power when printing high-melting-point materials, etc.

[0059] In the control method for the 3D printer and the control device 30 for the 3D printer 100 of this application, the sum of the duty cycles of the third control signal and the fourth control signal is greater than 1. This allows the two heating modules to work simultaneously for a short period of time to increase the total power when the 3D printer 100 needs to quickly replenish heat or when the environment in which the 3D printer 100 is located is dissipating heat too quickly. In this way, while ensuring the temperature control response speed, the requirement for flicker suppression is also taken into account by staggering the switching times of the two heating modules in the non-overlapping region.

[0060] Please see Figure 6 and Figure 7 In some implementations, a unit control cycle comprises multiple consecutive small control cycles, each of which comprises three half-waves.

[0061] The unit control cycle is the basic time unit for temperature maintenance control. In this embodiment, the unit control cycle is further divided into multiple consecutive smaller control cycles. A smaller control cycle is a more refined time unit than the unit control cycle, with a fixed duration and shorter than the unit control cycle. Each smaller control cycle contains an integer number of mains half-waves; in this embodiment, it specifically refers to three half-waves. For a 50Hz mains power supply, each half-wave has a duration of 10ms, therefore, the duration of a smaller control cycle is 30ms.

[0062] A half-wave is half a cycle of an AC mains power waveform, from zero to its peak and back to zero. Each half-wave can serve as the smallest power control unit. By controlling the power supply to the heating module in units of half-waves, precise control can be achieved.

[0063] The control method for the 3D printer and the control device 30 for the 3D printer 100 of this application refine the unit control cycle into multiple "small control cycles", and each "small control cycle" contains three AC half waves, so that the power distribution can closely follow the waveform cycle of the AC power, and more precise and smoother load control can be achieved.

[0064] Please see Figure 6 and Figure 7 In some implementations, the three half-waves in a small control cycle include a first half-wave, a second half-wave, and a third half-wave. When the duty cycle of the third and fourth control signals is 1 / 3, in each small control cycle of the third control signal, the first half-wave is used to control the first switch 13 to turn on, and the second and third half-waves are used to control the first switch 13 to turn off. In each small control cycle of the fourth control signal, the first and second half-waves are used to control the second switch 23 to turn off, and the third half-wave is used to control the second switch 23 to turn on.

[0065] The three half-waves in the small control cycle are defined sequentially as the first half-wave, the second half-wave, and the third half-wave. For 50Hz mains power, these three half-waves correspond to three consecutive time intervals: 0-10ms, 10-20ms, and 20-30ms, respectively. Each half-wave can function as an independent power control unit, enabling fine-grained power allocation.

[0066] A duty cycle of 1 / 3 means that each heating module receives power for only one half-wave within a complete small control cycle (three half-waves). This duty cycle setting is particularly suitable for operating conditions with low power demand during the temperature maintenance phase, minimizing power surges while ensuring temperature stability.

[0067] In each small control cycle of the third control signal, the first half-wave is used to control the first switch 13 to turn on. That is, at the beginning of the small control cycle, the main control chip immediately outputs a high-level signal to drive the first switch 13 to turn on, so that the first heating module 11 can obtain power during the first half-wave. Correspondingly, in each small control cycle of the third control signal, the second and third half-waves are used to control the first switch 13 to turn off, ensuring that the first heating module 11 stops working immediately after completing the heating of the first half-wave, leaving a time window for the operation of the second heating module 21. In this way, the power supply periods of the two heating modules can be completely isolated.

[0068] In each small control cycle of the fourth control signal, the first and second half-waves are used to control the second switch 23 to turn off, ensuring that the second heating module 21 is in a non-operating state during the first two half-waves of the small control cycle, thus avoiding overlap with the power supply period of the first heating module 11. The third half-wave in each small control cycle of the fourth control signal is used to control the second switch 23 to turn on, strictly limiting the power supply of the second heating module 21 to the last half-wave of each small control cycle, thereby maximizing the time interval between the turn-on times of the two heating modules.

[0069] Within each small control cycle, the power supply sequence is as follows: first heating module 11, no-load period, and second heating module 21. This power supply mode effectively disperses the power surges that might otherwise occur simultaneously into different time points. For 50Hz mains power, the first heating module 11 starts at 0ms and turns off at 10ms; the second heating module 21 starts at 20ms and turns off at 30ms, with a minimum time interval of 10ms between them.

[0070] The control method for the 3D printer and the control device 30 for the 3D printer 100 of this application achieve maximum separation of conduction time by fixing the conduction time of the first heating module 11 to the first half-wave of the small control cycle and fixing the conduction time of the second heating module 21 to the third half-wave of the small control cycle. This allows the current surge generated by the two heating modules to be buffered by the time span of the three half-waves, resulting in a smoother current change. This effectively suppresses the flickering of the lighting fixtures caused by voltage flicker to a level imperceptible to the human eye.

[0071] Please see Figure 6 and Figure 7 In some implementations, the three half-waves in a small control cycle include a first half-wave, a second half-wave, and a third half-wave. When the duty cycle of the third and fourth control signals is 1 / 3, in each small control cycle of the third control signal, the first half-wave is used to control the first switch 13 to turn on, and the second and third half-waves are used to control the first switch 13 to turn off. In each small control cycle of the fourth control signal, the first and third half-waves are used to control the second switch 23 to turn off, and the second half-wave is used to control the second switch 23 to turn on.

[0072] Specifically, in each small control cycle of the third control signal, the first half-wave is used to control the first switch 13 to be turned on. That is, when each small control cycle begins, the controller first activates the first switch 13, so that the first heating module 11 immediately obtains a complete half-wave of energy input.

[0073] In each small control cycle of the fourth control signal, the second half-wave is used to control the second switch 23 to turn on. That is, after the first heating module 11 stops receiving power, the second heating module 21 immediately receives power in the following half-wave, achieving a seamless connection between the two. In this way, a near-continuous energy supply can be provided for the heating module with low thermal inertia.

[0074] The control method for the 3D printer and the control device 30 for the 3D printer 100 of this application fix the conduction time of the first heating module 11 in the first half-wave of the small control cycle and fix the conduction time of the second heating module 21 in the second half-wave of the small control cycle. The conduction times of the two heating modules are closely adjacent but do not overlap, which can also avoid simultaneous switching on and off, realize time-sharing control, and is especially suitable for heating modules with low thermal inertia (very fast heating / cooling). It can reduce the large temperature fluctuation of heating modules with low thermal inertia, thereby achieving more accurate and stable temperature control.

[0075] Please see Figure 8 Thirdly, this application provides a 3D printer 100, which includes a memory 50 and a processor 40. The memory 50 is configured to store a computer program 202, and the processor 40 implements the control method described in any of the above embodiments when executing the computer program 202.

[0076] Please see Figure 9 Fourthly, this application provides a 3D printer 100, which includes the control device 30 described in any of the above embodiments.

[0077] Please see Figure 10 Fifthly, this application provides a computer-readable storage medium 200 having a computer program 202 stored thereon, which, when executed by a processor 40, implements the control method of any of the above embodiments.

[0078] In the 3D printer 100 and computer-readable storage medium 200 of this application, during the heating phase of the two heating modules, a first control signal and a second control signal with a relatively large duty cycle are used to control the two heating modules to heat up rapidly, so that the printing material can be melted and printing can be performed in a short time, shortening the waiting time before printing and improving the user experience; moreover, after the two heating modules reach their respective target temperatures, periodic unit control signals (a third control signal and a fourth control signal) with a relatively small duty cycle are used to control the two heating modules to enter the temperature maintenance phase, so that the temperature of the heating modules is maintained within the temperature range that can melt the printing material, and the third control signal is set. The first and second switches 23 are turned on at different times by the first and fourth control signals, and the first and second switches 23 are also turned off at different times. This avoids the simultaneous connection and disconnection of two high-power loads from the mains power grid. This time-sharing control strategy disperses the originally concentrated and abrupt power surges to different time points, greatly smoothing the total current drawn from the mains power grid. This effectively suppresses voltage flicker caused by frequent load connection or disconnection, and further suppresses severe flickering of lighting fixtures connected to the same circuit as the 3D printer 100. This eliminates the health threat to photosensitive users and improves user safety and experience.

[0079] The technical features of the embodiments described above can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as the combination of these technical features does not contradict each other, it should be considered within the scope of this specification. Furthermore, other implementation methods can be derived from the above embodiments, allowing for structural and logical substitutions and changes without departing from the scope of this disclosure.

[0080] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A control method for a 3D printer, characterized in that, The 3D printer includes a first switch, a first heating module, a second switch, and a second heating module. The first switch and the first heating module are connected in series to form a first branch, and the second switch and the second heating module are connected in series to form a second branch. The first branch and the second branch are connected in parallel to the mains power grid. The first heating module and the second heating module include a heating phase and a temperature maintenance phase. The heating power required by the first heating module in the heating phase is greater than the heating power required in the temperature maintenance phase, and the heating power required by the second heating module in the heating phase is greater than the heating power required in the temperature maintenance phase. The control method includes: When the first heating module and the second heating module are in the heating stage, a first control signal and a second control signal are sent to the first switch and the second switch respectively. The temperature of the first heating module is obtained. After the temperature of the first heating module reaches the first target temperature, a third control signal is sent to the first switch to put the first heating module into a temperature maintenance phase. The duty cycle of the third control signal is less than that of the first control signal. The temperature of the second heating module is obtained. After the temperature of the second heating module reaches the second target temperature, a fourth control signal is sent to the second switch to put the second heating module into a temperature maintenance phase. The duty cycle of the fourth control signal is less than that of the second control signal. Wherein, the third control signal and the fourth control signal are periodic unit control signals; within the unit control cycle, the moment when the third control signal controls the first switch to turn on is the first moment, and the moment when the third control signal controls the first switch to turn off is the second moment; the moment when the fourth control signal controls the second switch to turn on is the third moment, and the moment when the fourth control signal controls the first switch to turn off is the fourth moment; the first moment is different from the third moment, and the second moment is different from the fourth moment.

2. The control method according to claim 1, characterized in that, The 3D printer includes a heated bed module, a cavity heating module, and a hot end heating module; The first heating module and the second heating module are any two different heating modules among the heated bed heating module, the cavity heating module and the hot end heating module.

3. The control method according to claim 1, characterized in that, The heating power P12 required by the first heating module to maintain the temperature and the heating power P22 required by the second heating module to maintain the temperature satisfy the following relationship: 1%≤(P12-P22) / P12≤20%.

4. The control method according to claim 1, characterized in that, When the sum of the duty cycles of the third control signal and the fourth control signal is equal to 1, the third control signal controls the moment when the first switch is turned on, and the fourth control signal controls the second switch to be turned off. The third control signal controls when the first switch is turned off, and the fourth control signal controls when the second switch is turned on.

5. The control method according to claim 1, characterized in that, When the sum of the duty cycles of the third control signal and the fourth control signal is less than 1, the first switch and the second switch are simultaneously in the off state within the unit control cycle.

6. The control method according to claim 1, characterized in that, When the sum of the duty cycles of the third control signal and the fourth control signal is greater than 1, the first switch and the second switch are simultaneously in the on state within the unit control cycle.

7. The control method according to any one of claims 1-6, characterized in that, The unit control cycle comprises multiple consecutive small control cycles, each of which comprises three half-waves.

8. The control method according to claim 7, characterized in that, The three half-waves in the small control cycle include the first half-wave, the second half-wave, and the third half-wave; When the duty cycle of the third control signal and the fourth control signal is 1 / 3, the first half-wave of the third control signal in each small control cycle is used to control the first switch to be turned on, and the second half-wave and the third half-wave of the third control signal in each small control cycle are used to control the first switch to be turned off. In each small control cycle of the fourth control signal, the first half-wave and the second half-wave are used to control the second switch to turn off, and the third half-wave is used to control the second switch to turn on.

9. The control method according to claim 7, characterized in that, The three half-waves in the small control cycle include the first half-wave, the second half-wave, and the third half-wave; When the duty cycle of the third control signal and the fourth control signal is 1 / 3, the first half-wave of the third control signal in each small control cycle is used to control the first switch to be turned on, and the second half-wave and the third half-wave of the third control signal in each small control cycle are used to control the first switch to be turned off. In each small control cycle of the fourth control signal, the first half-wave and the third half-wave are used to control the second switch to turn off, and the second half-wave is used to control the second switch to turn on.

10. A control device for a 3D printer, characterized in that, The 3D printer includes: The system comprises a first switch, a first heating module, a second switch, and a second heating module. The first switch and the first heating module are connected in series to form a first branch, and the second switch and the second heating module are connected in series to form a second branch. The first branch and the second branch are connected in parallel to the mains power grid. The first heating module and the second heating module each include a heating stage and a temperature maintenance stage. The heating power required by the first heating module during the heating stage is greater than the heating power required during the temperature maintenance stage, and the heating power required by the second heating module during the heating stage is greater than the heating power required during the temperature maintenance stage. The control device includes: The transmitting module is configured to: send a first control signal and a second control signal to the first switch and the second switch respectively when the first heating module and the second heating module are in the heating stage; and The acquisition module is configured to acquire the temperature of the first heating module; The sending module is further configured to: after the temperature of the first heating module reaches the first target temperature, send a third control signal to the first switch to put the first heating module into a temperature maintenance phase, wherein the duty cycle of the third control signal is less than the duty cycle of the first control signal. The acquisition module is further configured to acquire the temperature of the second heating module; The sending module is further configured to: after the temperature of the second heating module reaches the second target temperature, send a fourth control signal to the second switch to put the second heating module into a temperature maintenance phase; the duty cycle of the fourth control signal is less than the duty cycle of the second control signal; Wherein, the third control signal and the fourth control signal are periodic unit control signals; within the unit control cycle, the moment when the third control signal controls the first switch to turn on is the first moment, and the moment when it controls the first switch to turn off is the second moment; the moment when the fourth control signal controls the second switch to turn on is the third moment, and the moment when it controls the second switch to turn off is the fourth moment; the first moment is different from the third moment, and the second moment is different from the fourth moment.

11. A 3D printer, characterized in that, The 3D printer includes a memory and a processor, the memory being configured to store a computer program, and the processor, when executing the computer program, implementing the control method according to any one of claims 1-9; or, The 3D printer includes the control device as described in claim 10.

12. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the control method as described in any one of claims 1-9.

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