Leveling detection circuit, leveling detection circuit, method and device for three-dimensional printer

Abstract

The present invention discloses a leveling detection circuit, a leveling detection circuit, a method and a device for a three-dimensional printer. The leveling detection circuit of the three-dimensional printer includes a leveling sensor, a signal amplifying circuit, a signal sampling and holding circuit and a differential amplifying circuit, wherein the leveling sensor is electrically connected to the signal amplifying circuit, the signal amplifying circuit is electrically connected to the signal sampling and holding circuit, the signal sampling and holding circuit and the signal amplifying circuit are electrically connected to the differential amplifying circuit respectively; the signal amplifying circuit is used to collect and amplify the real-time voltage signal; the signal sampling and holding circuit is used to sample and output a first voltage signal; the differential amplifying circuit is used to amplify the difference between the real-time voltage signal and the first voltage signal, and output a second voltage signal to the control circuit of the three-dimensional printer, so that the control circuit determines whether the leveling sensor touches the printing platform according to the second voltage signal. The above-mentioned leveling detection circuit can reduce the cost of the circuit and enhance the reliability of the circuit.

Description

Technical Field

[0001] The present invention and the technical field of three-dimensional printers, in particular, relate to a leveling detection circuit, a leveling detection circuit, a leveling detection method and a leveling detection device of a three-dimensional printer and a three-dimensional printer. Background Art

[0002] A three-dimensional printer, also known as a 3D printer, refers to a printing device that uses a rapid prototyping (RP) process to create a three-dimensional model by stacking layers. The operation process of a three-dimensional printer is similar to that of a traditional printer, but a traditional printer prints ink on paper to form a two-dimensional plane drawing, while a three-dimensional printer stacks liquid photosensitive resin materials, molten plastic filaments, gypsum powder and other materials on a printing platform by spraying binders or extruding them to form a three-dimensional entity.

[0003] FDM (Fused Deposition Modeling) is one of the more commonly used processes for 3D printers. For FDM 3D printers, printer leveling is a very important task before printing. If the printer platform is uneven or tilted, it will cause unevenness in the first layer of printing. Whether the first layer of printing can be evenly and firmly attached to the platform will directly affect the overall printing effect of the 3D printer.

[0004] At present, the most common way to level FDM printers is to manually rotate the nut to adjust the distance between the nozzle and the platform, or to use a leveling circuit composed of expensive circuit modules such as a control circuit and a digital-to-analog conversion module inside the 3D printer, and then perform leveling through the software algorithm inside the control circuit. However, the above leveling methods are expensive on the one hand, and on the other hand, due to the problem of sensor installation, certain errors will occur, resulting in inaccurate stress measurement. In addition, when the leveling module contains a control circuit, it will also involve complex and cumbersome issues such as software burning and version management. Summary of the invention

[0005] In view of this, the present application provides a leveling detection circuit, a leveling detection circuit, a leveling detection method and a leveling detection device of a 3D printer, and a 3D printer, the main purpose of which is to improve the technical problems of high cost and inaccurate stress measurement of existing leveling detection circuits.

[0006] According to a first aspect of the present invention, a leveling detection circuit of a 3D printer is provided, the leveling detection circuit of the 3D printer comprising a leveling sensor, a signal amplification circuit, a signal sampling and holding circuit and a differential amplification circuit, wherein:

[0007] The leveling sensor is electrically connected to the signal amplifying circuit, the signal amplifying circuit is electrically connected to the signal sampling and holding circuit, and the signal sampling and holding circuit and the signal amplifying circuit are electrically connected to the differential amplifying circuit respectively;

[0008] Among them, the signal amplification circuit is used to collect and amplify the real-time voltage signal output by the leveling sensor; the signal sampling and holding circuit is used to sample and output the first voltage signal output by the signal amplification circuit before the leveling sensor touches the printing platform; the differential amplifier circuit is used to amplify the difference between the amplified real-time voltage signal and the first voltage signal, and output the second voltage signal to the control circuit of the 3D printer, so that the control circuit of the 3D printer determines whether the leveling sensor touches the printing platform according to the second voltage signal.

[0009] In one embodiment of the present invention, optionally, the signal sampling and holding circuit includes a first voltage follower, a control switch, a second voltage follower and a holding capacitor, wherein the first voltage follower, the control switch and the second voltage follower are connected in series in sequence, one end of the holding capacitor is connected between the control switch and the second voltage follower, and the other end is electrically connected to the ground end, and the control end of the control switch is electrically connected to the control circuit; when the control switch receives a calibration signal sent by the control circuit of the 3D printer, the control switch is closed, the first voltage follower receives the first voltage signal output by the signal amplification circuit, and charges the holding capacitor; when the calibration signal disappears, the control switch is disconnected, and the holding capacitor holds the first voltage signal.

[0010] In one embodiment of the present invention, optionally, the signal sampling and holding circuit also includes a button, wherein one end of the button is electrically connected to the control end of the control switch, and the other end of the button is electrically connected to the ground end; when the button is pressed, the control switch is closed, the first voltage follower receives the first voltage signal output by the signal amplification circuit, and charges the holding capacitor; when the button is popped up, the control switch is disconnected, and the holding capacitor holds the first voltage signal.

[0011] According to a second aspect of the present invention, a leveling detection circuit for a 3D printer is provided, the leveling detection circuit comprising a control circuit and a leveling detection circuit for a 3D printer as described in any one of the above embodiments, wherein:

[0012] The control circuit is electrically connected to the differential amplifier circuit of the leveling detection circuit of the 3D printer, and is used to receive the second voltage signal output by the differential amplifier circuit, and to determine whether the second voltage signal is greater than a preset voltage value; if greater, it is determined that the leveling sensor touches the printing platform; if not greater, it is determined that the leveling sensor does not touch the printing platform.

[0013] In one embodiment of the present invention, optionally, the control circuit is also electrically connected to the signal sampling and holding circuit of the leveling detection circuit of the 3D printer, and is used to output a calibration signal to the signal sampling and holding circuit when the leveling sensor does not touch the printing platform, so that the signal sampling and holding circuit samples and outputs the first voltage signal amplified by the signal amplification circuit.

[0014] In one embodiment of the present invention, optionally, the signal sampling and holding circuit includes a first voltage follower, a control switch, a second voltage follower and a holding capacitor, wherein the first voltage follower, the control switch and the second voltage follower are connected in series in sequence, one end of the holding capacitor is connected between the control switch and the second voltage follower, and the other end is electrically connected to the ground end, and the control circuit is electrically connected to the control end of the control switch; when the control circuit outputs a calibration signal to the signal sampling and holding circuit, the control switch is closed, the first voltage follower receives the first voltage signal output by the signal amplification circuit, and charges the holding capacitor; when the calibration signal disappears, the control switch is disconnected, and the holding capacitor holds the first voltage signal.

[0015] According to a third aspect of the present invention, a leveling detection method for a 3D printer is provided, the method comprising:

[0016] Receiving a second voltage signal output by a differential amplifier circuit of a leveling detection circuit of a 3D printer, and determining whether the second voltage signal is greater than a preset voltage value;

[0017] If the second voltage signal is greater than the preset voltage value, it is determined that the leveling sensor touches the printing platform;

[0018] If the second voltage signal is not greater than the preset voltage value, it is determined that the leveling sensor does not touch the printing platform.

[0019] In one embodiment of the present invention, optionally, before receiving the second voltage signal output by the differential amplifier circuit of the leveling detection circuit of the 3D printer, the method further includes: when the leveling sensor of the leveling detection circuit of the 3D printer does not touch the printing platform, outputting a calibration signal to the signal sampling and holding circuit of the leveling detection circuit of the 3D printer, so that the signal sampling and holding circuit samples and outputs the first voltage signal amplified by the signal amplifier circuit.

[0020] According to a fourth aspect of the present invention, there is provided a leveling detection device for a 3D printer, the device comprising:

[0021] A voltage signal determination module, used for receiving a second voltage signal output by a differential amplifier circuit of a leveling detection circuit of a 3D printer, and determining whether the second voltage signal is greater than a preset voltage value;

[0022] A first result determination module, configured to determine that the leveling sensor touches the printing platform if the second voltage signal is greater than a preset voltage value;

[0023] The second result determination module is used to determine that the leveling sensor does not touch the printing platform if the second voltage signal is not greater than a preset voltage value.

[0024] According to a fifth aspect of the present invention, a three-dimensional printer is provided. The three-dimensional printer includes the leveling detection circuit of the three-dimensional printer described in any one of the above embodiments.

[0025] The present invention provides a leveling detection circuit, a leveling detection circuit, a leveling detection method, a leveling detection device and a three-dimensional printer. The leveling detection function is realized by setting analog circuits such as a leveling sensor, a signal amplification circuit, a signal sampling and holding circuit and a differential amplifier circuit in the leveling detection circuit, thereby eliminating the relatively expensive control module and digital-to-analog conversion module in the existing leveling detection circuit, reducing the cost of the leveling detection circuit, and enhancing the reliability of the leveling detection circuit without complicated calculations. In addition, the leveling detection circuit determines whether the leveling sensor touches the printing platform by the difference between the amplified real-time voltage signal and the amplified first voltage signal before the leveling sensor touches the printing platform, effectively offsetting the stress error value generated during the installation of the leveling sensor, thereby improving the accuracy of stress measurement.

[0026] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0028] Figure 1 A schematic diagram of the circuit structure of a leveling detection circuit of a 3D printer provided by an embodiment of the present invention is shown;

[0029] Figure 2 A circuit structure diagram of a signal sampling and holding circuit provided by an embodiment of the present invention is shown;

[0030] Figure 3 A schematic flow chart of a leveling detection method for a 3D printer provided by an embodiment of the present invention is shown;

[0031] Figure 4A schematic structural diagram of a leveling detection device for a 3D printer provided in an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0032] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other without conflict.

[0033] One embodiment of the present invention first provides a leveling detection circuit for a 3D printer, such as Figure 1 As shown, the leveling detection circuit of the 3D printer includes a leveling sensor 11, a signal amplifying circuit 12, a signal sampling and holding circuit 13, and a differential amplifying circuit 14, wherein the leveling sensor 11 is electrically connected to the signal amplifying circuit 12, the signal amplifying circuit 12 is electrically connected to the signal sampling and holding circuit 13, and the signal sampling and holding circuit 13 and the signal amplifying circuit 12 are electrically connected to the differential amplifying circuit 14 respectively. In this embodiment, the signal amplifying circuit 12 can be used to collect and amplify the real-time voltage signal output by the leveling sensor 11, the signal sampling and holding circuit 13 can be used to sample and output the first voltage signal output by the signal amplifying circuit 12 before the leveling sensor 11 touches the printing platform, and the differential amplifying circuit 14 can be used to amplify the difference between the amplified real-time voltage signal and the first voltage signal, and output a second voltage signal to the control circuit of the 3D printer, so that the control circuit of the 3D printer can judge whether the leveling sensor touches the printing platform according to the second voltage signal.

[0034] Specifically, the leveling sensor can be set at the nozzle of the 3D printer. When the 3D printer is leveled, when the nozzle of the 3D printer does not touch the printing platform, the signal amplification circuit can collect and amplify the real-time voltage signal output by the leveling sensor, and the signal sampling and holding circuit can sample and hold the real-time voltage signal to obtain a first voltage signal, and then the signal sampling and holding circuit inputs the first voltage signal into the differential amplifier circuit. Further, the control circuit of the 3D printer controls the nozzle of the printer to move toward the printing platform at a set position, and the signal amplification circuit can collect and amplify the real-time voltage signal output by the leveling sensor in real time and input it into the differential amplifier circuit. After receiving the amplified real-time voltage signal, the differential amplifier circuit can perform a difference operation on the amplified real-time voltage signal and the first voltage signal held by the signal sampling and holding circuit, and amplify the result of the difference operation to obtain a second voltage signal. Finally, the differential amplifier circuit inputs the second voltage signal into the control circuit of the 3D printer, so that the control circuit of the 3D printer performs a leveling detection judgment according to the second voltage signal. In this embodiment, if the second voltage signal is greater than the preset voltage value, it is confirmed that the print head touches the printing platform.

[0035] Furthermore, the control circuit of the 3D printer can control the nozzle of the printer to perform leveling detection on each position on the printing platform in a certain order to achieve final leveling. It can be understood that when the signal sampling and holding circuit samples and holds the real-time voltage signal to obtain the first voltage signal, the first voltage signal can be obtained in sequence at each position, or the first voltage signal can be obtained only once during the entire leveling process.

[0036] In the above embodiment, the leveling sensor, signal amplification circuit, signal sampling and holding circuit and differential amplification circuit in the leveling detection circuit are all analog circuits. Among them, the leveling sensor can be a sensor such as a pressure sensor or a Hall sensor whose output signal can change with pressure and distance; the signal amplification circuit and the differential amplification circuit can be operational amplification circuits such as a differential amplification circuit or a dual op amp instrumentation amplification circuit; the signal sampling and holding circuit can be an analog circuit with a signal holding function composed of a voltage follower and a capacitor. It can be seen that the leveling detection circuit is relatively low in cost and relatively stable as a whole. In the process of leveling detection, the leveling detection circuit only needs to cooperate with the control circuit of the 3D printer to first collect the first voltage signal of the leveling sensor before it touches the printing platform, and collect the real-time voltage signal output by the leveling sensor during the leveling process in real time, and then output a second voltage signal with a detection function. Since the second voltage signal is an amplified signal of the difference between the amplified real-time voltage signal and the first voltage signal, it is more accurate to use the second voltage signal for stress measurement.

[0037] It should be noted that the control circuit of the 3D printer in this embodiment may not be a component of the leveling detection circuit, but a core control module in the 3D printer. Through the control circuit of the 3D printer, the 3D printer can perform various functions such as the leveling detection function and the 3D printing function. However, the circuit function of the leveling detection circuit in this embodiment is not realized by relying on the control circuit of the 3D printer, but is realized by means of the various circuit modules in the leveling detection circuit and the connection relationship between the various modules. After the leveling detection circuit outputs the second voltage signal, the control circuit only needs to determine whether the second voltage signal is higher than the preset voltage value to determine whether the leveling sensor touches the printing platform. The calculation process is simple and quick.

[0038] The leveling detection circuit of the three-dimensional printer proposed in the embodiment of the present invention realizes the leveling detection function by setting analog circuits such as a leveling sensor, a signal amplification circuit, a signal sampling and holding circuit, and a differential amplifier circuit, thereby eliminating the relatively expensive control module and digital-to-analog conversion module in the existing leveling detection circuit, reducing the cost of the leveling detection circuit, and enhancing the reliability of the leveling detection circuit without complicated calculations. In addition, the leveling detection circuit determines whether the leveling sensor touches the printing platform by the difference between the amplified real-time voltage signal and the amplified first voltage signal before the leveling sensor touches the printing platform, effectively offsetting the stress error value generated during the installation of the leveling sensor, thereby improving the accuracy of stress measurement.

[0039] In one embodiment of the present invention, optionally, Figure 2 As shown, the signal sampling and holding circuit includes a first voltage follower N1, a control switch S, a second voltage follower N2 and a holding capacitor C. The first voltage follower N1, the control switch S and the second voltage follower N2 are connected in series in sequence, one end of the holding capacitor C is connected between the control switch S and the second voltage follower N2, and the other end is electrically connected to the ground end, and the control end of the control switch S is electrically connected to the control circuit. Specifically, when the control switch S receives the calibration signal sent by the control circuit of the 3D printer, the control switch S is closed, the first voltage follower N1 receives the first voltage signal output by the signal amplification circuit, and charges the holding capacitor C; when the calibration signal disappears, the control switch S is disconnected, and the holding capacitor C holds the first voltage signal.

[0040] In the above embodiment, the control switch S can be controlled by the control circuit of the 3D printer to sample and hold the real-time voltage signal collected by the signal amplification circuit at the current moment. That is, when the control circuit sends a calibration signal, the signal sampling and holding circuit can sample the real-time voltage signal amplified at the current moment through the first voltage follower N1; when the calibration signal disappears after a period of time, the signal sampling and holding circuit can hold the voltage signal through the holding capacitor C and the second voltage follower N2, and obtain the first voltage signal. In this embodiment, at any time before the leveling sensor touches the printing platform, the control switch S can receive the calibration signal sent by the control circuit of the 3D printer, wherein the sending of the calibration signal can be controlled manually or sent in a timing manner, which is not specifically limited in this embodiment. The above circuit can realize the function of maintaining the voltage signal through two simple voltage followers, a switch and a capacitor, with low cost and strong stability.

[0041] In one embodiment of the present invention, optionally, the signal sampling and holding circuit further includes a physical button ( Figure 2(not shown in the figure), wherein one end of the button is electrically connected to the control end of the control switch S, and the other end of the button is electrically connected to the ground end. When the button is pressed, the control switch is closed, the first voltage follower receives the first voltage signal output by the signal amplification circuit, and charges the holding capacitor; when the button is released, the control switch is disconnected, and the holding capacitor holds the first voltage signal. In this embodiment, the control switch S can also be controlled by a physical button to sample and hold the real-time voltage signal collected by the signal amplification circuit at the current moment. By setting a physical button in the signal sampling and holding circuit, this embodiment enables the signal sampling and holding circuit to sample and output the first voltage signal at any time, thereby effectively improving the flexibility of the leveling detection circuit in sampling the first voltage signal.

[0042] In one embodiment of the present invention, optionally, the signal amplification circuit and the differential amplification circuit can be a dual op amp instrumentation amplifier circuit. The dual op amp instrumentation amplifier circuit refers to two general-purpose operational amplifiers integrated on a single chip. This amplifier circuit has the characteristics of high gain, high common-mode rejection ratio, wide common-mode range, simple compensation, stable operation, good temperature stability, etc. Therefore, by setting a dual op amp instrumentation amplifier circuit in the leveling detection circuit, the overall stability of the circuit can be further improved. In other optional embodiments, the signal amplification circuit and the differential amplification circuit can also be other types of operational amplifier circuits, such as differential amplifier circuits, etc., which are not specifically limited in this embodiment.

[0043] In one embodiment of the present invention, optionally, a variable resistor may be provided in the signal amplification circuit and / or the differential amplification circuit, and the variable resistor may be used to adjust the voltage amplification factor of the signal amplification circuit and / or the differential amplification circuit. In this embodiment, by providing a variable resistor with adjustable resistance in the signal amplification circuit and / or the differential amplification circuit, the amplification factors of the two operational amplifier circuits may be adjusted by the variable resistor during the detection and leveling process, thereby improving the sensitivity of signal detection. In this embodiment, the voltage amplification factor of the signal amplification circuit and / or the differential amplification circuit is adjusted by adjusting the resistance of the variable resistor, which is simple and has high adjustment efficiency.

[0044] In one embodiment of the present invention, the leveling sensor can be optionally arranged at the nozzle of the 3D printer so that the leveling sensor can sensitively detect the distance change between the nozzle and the printing platform. In this embodiment, the leveling sensor can be a pressure sensor or a Hall sensor, etc., whose output signal can change with pressure and distance. For example, the leveling sensor can be a strain gauge, etc., which is a simple, highly sensitive and low-cost sensor.

[0045] Furthermore, an embodiment of the present invention also provides a leveling detection circuit for a 3D printer, the leveling detection circuit comprising a control circuit and the leveling detection circuit for a 3D printer described in any one of the above embodiments. In this embodiment, the control circuit can be electrically connected to the differential amplifier circuit of the leveling detection circuit of the 3D printer, and can be used to receive a second voltage signal output by the differential amplifier circuit, and to determine whether the second voltage signal is greater than a preset voltage value. When the second voltage signal is greater than the preset voltage value, the control circuit determines that the leveling sensor touches the printing platform; when the second voltage signal is not greater than the preset voltage value, the control circuit determines that the leveling sensor does not touch the printing platform.

[0046] Specifically, when leveling the 3D printer, the control circuit of the 3D printer can collect and amplify the real-time voltage signal output by the leveling sensor through the signal amplification circuit when the nozzle is away from the printing platform of the 3D printer, and sample and hold the real-time voltage signal through the signal sampling and holding circuit to obtain a first voltage signal, and then input the first voltage signal into the differential amplifier circuit through the signal sampling and holding circuit. Further, the control circuit of the 3D printer can control the nozzle of the printer to move toward the printing platform at a set position. At this time, the signal amplification circuit of the leveling detection circuit can collect and amplify the real-time voltage signal output by the leveling sensor in real time and input it into the differential amplifier circuit. After receiving the amplified real-time voltage signal, the differential amplifier circuit can perform a difference operation on the amplified real-time voltage signal and the first voltage signal held by the signal sampling and holding circuit, and amplify the result of the difference operation to obtain a second voltage signal. Finally, the differential amplifier circuit inputs the second voltage signal into the control circuit, and the control circuit judges the second voltage signal and the preset voltage value. If the second voltage signal is greater than the preset voltage value, it is confirmed that the leveling sensor touches the printing platform.

[0047] In this embodiment, the control circuit serves as the core control module of the 3D printer, and can control the 3D printer to perform various functions such as the leveling detection function and the 3D printing function. After the leveling detection circuit outputs the second voltage signal, the control circuit only needs to determine whether the second voltage signal is higher than the preset voltage value to determine whether the leveling sensor touches the printing platform, and the calculation process is simple and fast. In addition, by using the control circuit of the 3D printer to realize the leveling detection function, the relatively expensive control module and digital-to-analog conversion module in the leveling detection circuit can be omitted, thereby reducing the overall cost of the circuit and enhancing the overall reliability of the circuit.

[0048] In one embodiment of the present invention, optionally, the control circuit is also electrically connected to the signal sampling and holding circuit of the leveling detection circuit of the 3D printer, and can be used to output a calibration signal to the signal sampling and holding circuit when the leveling sensor does not touch the printing platform, so that the signal sampling and holding circuit samples and outputs the first voltage signal amplified by the signal amplification circuit. In this embodiment, the control circuit can output a calibration signal to the signal sampling and holding circuit at any time before the leveling sensor touches the printing platform, so that the signal sampling and holding circuit can sample and hold the real-time voltage signal collected at the current moment, and obtain the first voltage signal. Among them, the first voltage signal is collected before the leveling sensor touches the printing platform, so the first voltage signal can be used as a calibration signal for the leveling detection circuit, and in the subsequent continuous collection of real-time voltage signals and the difference operation amplification of the real-time voltage signal and the first voltage signal, it can be determined whether the leveling sensor touches the printing platform. In this embodiment, by sending a calibration signal to control the sampling and holding circuit to sample and output the first voltage signal, the stress error generated by the leveling sensor during installation can be offset, thereby improving the accuracy of stress measurement.

[0049] In one embodiment of the present invention, optionally, Figure 2 As shown, the signal sampling and holding circuit includes a first voltage follower N1, a control switch S, a second voltage follower N2 and a holding capacitor C. Among them, the first voltage follower N1, the control switch S and the second voltage follower N2 are connected in series in sequence, one end of the holding capacitor C is connected between the control switch S and the second voltage follower N2, and the other end is electrically connected to the ground terminal, and the control circuit is electrically connected to the control end of the control switch S. Specifically, when the control circuit outputs a calibration signal to the signal sampling and holding circuit, the control switch S is closed, the first voltage follower receives the first voltage signal output by the signal amplification circuit, and charges the holding capacitor; when the calibration signal disappears, the control switch S is disconnected, and the holding capacitor holds the first voltage signal. The above circuit enables the signal sampling and holding circuit to respond quickly to the command of the control circuit by electrically connecting the control circuit to the control switch of the signal sampling and holding circuit, thereby sampling the first voltage signal in time.

[0050] On the other hand, an embodiment of the present invention further provides a three-dimensional printer, which includes the leveling detection circuit of the three-dimensional printer described in any of the above embodiments, and the leveling detection circuit includes a control circuit and the leveling detection circuit of the three-dimensional printer described in any of the above embodiments. In this embodiment, the leveling detection circuit is arranged in the three-dimensional printer, and the control circuit in the leveling detection circuit is electrically connected to the differential amplifier circuit of the leveling detection circuit, and can be used to receive the second voltage signal output by the differential amplifier circuit, and determine whether the second voltage signal is greater than a preset voltage value. When the second voltage signal is greater than the preset voltage value, the control circuit determines that the leveling sensor touches the printing platform; when the second voltage signal is not greater than the preset voltage value, the control circuit determines that the leveling sensor does not touch the printing platform.

[0051] Specifically, when leveling the 3D printer, the control circuit of the 3D printer can collect and amplify the real-time voltage signal output by the leveling sensor through the signal amplification circuit when the nozzle is away from the printing platform of the 3D printer, and sample and hold the real-time voltage signal through the signal sampling and holding circuit to obtain a first voltage signal, and then input the first voltage signal into the differential amplifier circuit through the signal sampling and holding circuit. Further, the control circuit of the 3D printer can control the nozzle of the printer to move toward the printing platform at a set position. At this time, the signal amplification circuit of the leveling detection circuit can collect and amplify the real-time voltage signal output by the leveling sensor in real time and input it into the differential amplifier circuit. After receiving the amplified real-time voltage signal, the differential amplifier circuit can perform a difference operation on the amplified real-time voltage signal and the first voltage signal held by the signal sampling and holding circuit, and amplify the result of the difference operation to obtain a second voltage signal. Finally, the differential amplifier circuit inputs the second voltage signal into the control circuit, and the control circuit judges the second voltage signal and the preset voltage value. If the second voltage signal is greater than the preset voltage value, it is confirmed that the leveling sensor touches the printing platform.

[0052] The above-mentioned 3D printer realizes the leveling detection function by using its own control circuit, which can omit the relatively expensive control module and digital-to-analog conversion module in the leveling detection circuit, thereby reducing the overall cost of the circuit and enhancing the overall reliability of the circuit. In addition, the above-mentioned 3D printer determines whether the leveling sensor touches the printing platform by the difference between the real-time voltage signal and the first voltage signal amplified before the leveling sensor touches the printing platform, effectively offsetting the stress error value generated during the installation process of the leveling sensor, thereby improving the accuracy of stress measurement.

[0053] In one embodiment, Figure 3As shown, a leveling detection method for a 3D printer is provided, and the method is described by taking the method applied to the control circuit of the leveling detection circuit of the 3D printer as described in any of the above embodiments as an example, comprising the following steps:

[0054] 201. Receive a second voltage signal output by a differential amplifier circuit of a leveling detection circuit of a 3D printer, and determine whether the second voltage signal is greater than a preset voltage value.

[0055] 202. If the second voltage signal is greater than a preset voltage value, it is determined that the leveling sensor touches the printing platform.

[0056] 203. If the second voltage signal is not greater than the preset voltage value, it is determined that the leveling sensor does not touch the printing platform.

[0057] Specifically, the control circuit of the three-dimensional leveling detection circuit can be electrically connected to the differential amplifier circuit of the leveling detection circuit of the three-dimensional printer, and can receive the second voltage signal output by the differential amplifier circuit in real time during the leveling process of the three-dimensional printer, and determine whether the second voltage signal is greater than a preset voltage value. When the second voltage signal is greater than the preset voltage value, the control circuit can determine that the leveling sensor touches the printing platform; when the second voltage signal is not greater than the preset voltage value, the control circuit can determine that the leveling sensor does not touch the printing platform.

[0058] In this embodiment, the acquisition process of the second voltage signal is as follows: when the control circuit controls the nozzle to be away from the printing platform of the 3D printer, the control circuit can collect and amplify the real-time voltage signal output by the leveling sensor through the signal amplification circuit, and sample and hold the real-time voltage signal through the signal sampling and holding circuit to obtain the first voltage signal, and then input the first voltage signal into the differential amplifier circuit through the signal sampling and holding circuit. Further, the control circuit of the 3D printer can control the nozzle of the printer to move toward the printing platform at a set position. At this time, the signal amplification circuit of the leveling detection circuit can collect and amplify the real-time voltage signal output by the leveling sensor in real time and input it into the differential amplifier circuit. After receiving the amplified real-time voltage signal, the differential amplifier circuit can perform a difference operation on the amplified real-time voltage signal and the first voltage signal held by the signal sampling and holding circuit, and amplify the result of the difference operation to obtain the second voltage signal. Finally, the differential amplifier circuit inputs the second voltage signal into the control circuit, and the control circuit judges the second voltage signal and the preset voltage value. If the second voltage signal is greater than the preset voltage value, it is confirmed that the leveling sensor touches the printing platform. The leveling detection method provided in this embodiment only needs to determine whether the second voltage signal is higher than a preset voltage value to determine whether the leveling sensor touches the printing platform. The calculation process is simple and fast, and less resources are occupied.

[0059] In an optional embodiment, before receiving the second voltage signal output by the differential amplifier circuit of the leveling detection circuit of the 3D printer, the leveling detection method of the 3D printer further includes the following steps: when the leveling sensor of the leveling detection circuit of the 3D printer does not touch the printing platform, outputting a calibration signal to the signal sampling and holding circuit of the leveling detection circuit of the 3D printer. In this embodiment, the control circuit can also be electrically connected to the signal sampling and holding circuit of the leveling detection circuit of the 3D printer, and can output a calibration signal to the signal sampling and holding circuit when the leveling sensor does not touch the printing platform. Specifically, the control circuit can output a calibration signal to the signal sampling and holding circuit at any time before the leveling sensor does not touch the printing platform, so that the signal sampling and holding circuit can sample and hold the real-time voltage signal collected at the current time, and obtain a first voltage signal. Among them, the first voltage signal is collected before the leveling sensor does not touch the printing platform, so the first voltage signal can be used as the calibration signal of the leveling detection circuit, and in the subsequent continuous collection of real-time voltage signals and the difference operation amplification of the real-time voltage signal and the first voltage signal, it can be determined whether the leveling sensor touches the printing platform. In this embodiment, by sending a calibration signal to control the sampling and holding circuit to sample and output the first voltage signal, the stress error generated during the installation of the leveling sensor can be offset, thereby improving the accuracy of stress measurement.

[0060] Further, as Figure 3 The specific implementation of the method shown in the embodiment provides a leveling detection device for a 3D printer, such as Figure 4 As shown, the device includes: a voltage signal determination module 31, a first result determination module 32 and a second result determination module 33, wherein:

[0061] The voltage signal judging module 31 can be used to receive the second voltage signal output by the differential amplifier circuit of the leveling detection circuit of the 3D printer, and judge whether the second voltage signal is greater than a preset voltage value;

[0062] A first result determination module 32, which can be used to determine that the leveling sensor touches the printing platform if the second voltage signal is greater than a preset voltage value;

[0063] The second result determination module 33 may be used to determine that the leveling sensor does not touch the printing platform if the second voltage signal is not greater than a preset voltage value.

[0064] In a specific application scenario, the device also includes a calibration signal sending module 34, wherein the calibration signal sending module 34 can be used to output a calibration signal to the signal sampling and holding circuit of the leveling detection circuit of the 3D printer when the leveling sensor of the leveling detection circuit of the 3D printer does not touch the printing platform, so that the signal sampling and holding circuit samples and outputs the first voltage signal amplified by the signal amplification circuit.

[0065] It should be noted that for other corresponding descriptions of the functional units involved in the leveling detection device for a 3D printer provided in this embodiment, reference can be made to Figure 3 The corresponding description in will not be repeated here.

[0066] Based on the above Figure 3 The method shown in the embodiment also provides a storage medium on which a computer program is stored. When the program is executed by a processor, the above-mentioned Figure 3 The leveling detection method of the 3D printer is shown.

[0067] Based on this understanding, the technical solution of the present application can be embodied in the form of a software product. The software product to be identified can be stored in a non-volatile storage medium (which can be a CD-ROM, a USB flash drive, a mobile hard disk, etc.), including a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each implementation scenario of the present application.

[0068] Based on the above Figure 3 The method shown, and Figure 4 The embodiment of the leveling detection device of the 3D printer shown in the figure, in order to achieve the above-mentioned purpose, this embodiment also provides a physical device for leveling detection of the 3D printer, which can be a personal computer, a server, a smart phone, a tablet computer, a smart watch, or other network devices, etc., and the physical device includes a storage medium and a processor; the storage medium is used to store a computer program; the processor is used to execute the computer program to achieve the above-mentioned Figure 3 The method shown.

[0069] Optionally, the physical device may also include a user interface, a network interface, a camera, a radio frequency (RF) circuit, a sensor, an audio circuit, a WI-FI module, etc. The user interface may include a display, an input unit such as a keyboard, etc., and the optional user interface may also include a USB interface, a card reader interface, etc. The network interface may optionally include a standard wired interface, a wireless interface (such as a WI-FI interface), etc.

[0070] Those skilled in the art will appreciate that the physical device structure for leveling detection of a 3D printer provided in this embodiment does not constitute a limitation on the physical device, and may include more or fewer components, or a combination of certain components, or different component arrangements.

[0071] The storage medium may also include an operating system and a network communication module. The operating system is a program that manages the hardware of the physical device and the software resources to be identified, and supports the operation of the information processing program and other software and / or programs to be identified. The network communication module is used to realize the communication between the components inside the storage medium, and the communication with other hardware and software in the information processing physical device.

[0072] Through the description of the above implementation methods, those skilled in the art can clearly understand that the present application can be implemented by means of software plus a necessary general hardware platform, or by hardware. The present application realizes the function of leveling detection by setting analog circuits such as a leveling sensor, a signal amplification circuit, a signal sampling and holding circuit, and a differential amplifier circuit in the leveling detection circuit, thereby eliminating the relatively expensive control module and digital-to-analog conversion module in the existing leveling detection circuit. Compared with the prior art, the present solution reduces the cost of the leveling detection circuit, does not require complex calculations, and enhances the reliability of the leveling detection circuit. In addition, the above-mentioned leveling detection circuit determines whether the leveling sensor touches the printing platform by the difference between the amplified real-time voltage signal and the amplified first voltage signal before the leveling sensor touches the printing platform, effectively offsetting the stress error value generated during the installation of the leveling sensor, thereby improving the accuracy of stress measurement.

[0073] Those skilled in the art will appreciate that the accompanying drawings are only schematic diagrams of a preferred implementation scenario, and the modules or processes in the accompanying drawings are not necessarily necessary for implementing the present application. Those skilled in the art will appreciate that the modules in the devices in the implementation scenario can be distributed in the devices of the implementation scenario according to the description of the implementation scenario, or can be changed accordingly and located in one or more devices different from the present implementation scenario. The modules of the above-mentioned implementation scenario can be combined into one module, or can be further split into multiple submodules.

[0074] The above serial numbers of this application are only for description and do not represent the advantages and disadvantages of the implementation scenarios. The above disclosure is only a few specific implementation scenarios of this application, but this application is not limited to them, and any changes that can be thought of by technicians in this field should fall within the scope of protection of this application.

Claims

1. A leveling detection circuit for a 3D printer, characterized in that: The leveling detection circuit of the three-dimensional printer includes a leveling sensor, a signal amplification circuit, a signal sampling and holding circuit and a differential amplification circuit, wherein: The leveling sensor is electrically connected to the signal amplifying circuit, the signal amplifying circuit is electrically connected to the signal sampling and holding circuit, and the signal sampling and holding circuit and the signal amplifying circuit are electrically connected to the differential amplifying circuit respectively; The signal sampling and holding circuit comprises a first voltage follower, a control switch, a second voltage follower and a holding capacitor, wherein the first voltage follower, the control switch and the second voltage follower are connected in series in sequence, one end of the holding capacitor is connected between the control switch and the second voltage follower, and the other end is electrically connected to the ground end, and the control end of the control switch is electrically connected to the control circuit; when the control switch receives a calibration signal sent by the control circuit of the 3D printer, the control switch is closed, the first voltage follower receives the first voltage signal output by the signal amplification circuit, and charges the holding capacitor; when the calibration signal disappears, the control switch is disconnected, and the holding capacitor holds the first voltage signal; Among them, the signal amplification circuit is used to collect and amplify the real-time voltage signal output by the leveling sensor; the signal sampling and holding circuit is used to sample and output the first voltage signal output by the signal amplification circuit before the leveling sensor touches the printing platform; the differential amplifier circuit is used to amplify the difference between the amplified real-time voltage signal and the first voltage signal, and output a second voltage signal to the control circuit of the 3D printer, so that the control circuit of the 3D printer determines whether the leveling sensor touches the printing platform according to the second voltage signal.

2. The leveling detection circuit of the 3D printer according to claim 1, characterized in that: The signal sampling and holding circuit further comprises a button, wherein one end of the button is electrically connected to the control end of the control switch, and the other end of the button is electrically connected to the ground end; When the button is pressed, the control switch is closed, the first voltage follower receives the first voltage signal output by the signal amplification circuit, and charges the holding capacitor; when the button is released, the control switch is disconnected, and the holding capacitor holds the first voltage signal.

3. A leveling detection circuit for a 3D printer, characterized in that: The leveling detection circuit comprises a control circuit and a leveling detection circuit of a 3D printer as claimed in claim 1 or 2, wherein: The control circuit is electrically connected to the differential amplifier circuit of the leveling detection circuit of the 3D printer, and is used to receive a second voltage signal output by the differential amplifier circuit, and to determine whether the second voltage signal is greater than a preset voltage value; if greater than, it is determined that the leveling sensor touches the printing platform; if not greater than, it is determined that the leveling sensor does not touch the printing platform.

4. The leveling detection circuit according to claim 3, characterized in that: The control circuit is also electrically connected to the signal sampling and holding circuit of the leveling detection circuit of the 3D printer, and is used to output a calibration signal to the signal sampling and holding circuit when the leveling sensor does not touch the printing platform, so that the signal sampling and holding circuit samples and outputs the first voltage signal amplified by the signal amplification circuit.

5. The leveling detection circuit according to claim 4, characterized in that: The signal sampling and holding circuit includes a first voltage follower, a control switch, a second voltage follower and a holding capacitor, wherein: The first voltage follower, the control switch and the second voltage follower are connected in series in sequence, one end of the holding capacitor is connected between the control switch and the second voltage follower, and the other end is electrically connected to the ground end, and the control circuit is electrically connected to the control end of the control switch; When the control circuit outputs a calibration signal to the signal sampling and holding circuit, the control switch is closed, the first voltage follower receives the first voltage signal output by the signal amplification circuit, and charges the holding capacitor; when the calibration signal disappears, the control switch is disconnected, and the holding capacitor holds the first voltage signal.

6. A leveling detection method for a 3D printer, characterized in that: The method comprises: receiving a second voltage signal output by a differential amplifier circuit of a leveling detection circuit of a 3D printer as claimed in claim 1 or 2, and determining whether the second voltage signal is greater than a preset voltage value; If the second voltage signal is greater than the preset voltage value, it is determined that the leveling sensor touches the printing platform; If the second voltage signal is not greater than the preset voltage value, it is determined that the leveling sensor does not touch the printing platform.

7. The method according to claim 6, characterized in that Before receiving the second voltage signal output by the differential amplifier circuit of the leveling detection circuit of the 3D printer, the method further includes: When the leveling sensor of the leveling detection circuit of the 3D printer does not touch the printing platform, a calibration signal is output to the signal sampling and holding circuit of the leveling detection circuit of the 3D printer, so that the signal sampling and holding circuit samples and outputs the first voltage signal amplified by the signal amplification circuit.

8. A leveling detection device for a 3D printer, characterized in that: The device comprises: A voltage signal judging module, configured to receive a second voltage signal output by the differential amplifier circuit of the leveling detection circuit of the 3D printer according to claim 1 or 2, and judge whether the second voltage signal is greater than a preset voltage value; A first result determination module, configured to determine that the leveling sensor touches the printing platform if the second voltage signal is greater than the preset voltage value; The second result determination module is configured to determine that the leveling sensor does not touch the printing platform if the second voltage signal is not greater than the preset voltage value.

9. A three-dimensional printer, characterized in that: The three-dimensional printer comprises the leveling detection circuit of the three-dimensional printer according to any one of claims 3 to 5.

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