Height compensation method and system for printing equipment

Abstract

The invention provides a height compensation method and system for printing equipment, and relates to the technical field of printing. The method comprises the steps that the reference height corresponding to a preset measurement reference surface is determined, printing nozzles in the multi-nozzle 3D printing equipment are controlled to sequentially move to the position over the measurement reference surface and make contact with the measurement reference surface, the height value of the printing nozzles making contact with the measurement reference surface is determined, and the height value of the printing nozzles is determined based on a trigger signal in the touch process; the actual height deviation of each printing nozzle is measured; and based on the corresponding compensation height of the printing nozzle in the Z-axis direction, height compensation is performed on the printing nozzle in the Z-axis direction, so that full-automatic leveling and first layer optimization without manual intervention are realized, the uniformity, adhesive force and flatness of the printing first layer are ensured, the printing success rate and the equipment intelligence level are greatly improved, and the printing efficiency is improved. The problems that in traditional multi-head printing, the first layer is uneven, and the success rate is low are solved.

Description

Technical Field

[0001] This application relates to the field of printing equipment technology, and more specifically, to a height compensation method and system for a printing device. Background Technology

[0002] In the field of 3D printing technology, multi-nozzle 3D printing equipment is typically equipped with two or more independently controlled printheads to achieve multi-material, multi-color, or high-speed parallel printing, which can effectively reduce material waste, save printing time, and improve printing efficiency. However, due to factors such as mechanical assembly errors, structural deformation caused by long-term operation, thermal expansion effects, and platform warping, there are often deviations in the relative height between different printheads and the printing platform. If precise measurement and calibration are not performed, problems such as nozzle scraping of the platform, uneven material extrusion, uncontrolled layer thickness, and even printing failure can easily occur.

[0003] Currently, common methods for measuring the height of printing platforms include using laser triangulation or confocal optical sensors for height scanning, which can obtain high-precision three-dimensional topographic data and support dynamic leveling and tilt compensation.

[0004] However, this measurement method suffers from complex system integration and is prone to signal drift or measurement distortion on transparent or highly reflective platforms, limiting its application in popular multi-nozzle 3D printing equipment. Summary of the Invention

[0005] The purpose of this application is to provide a height compensation method and system for a printing device to address the shortcomings of the prior art, thereby solving the technical problems existing in the prior art.

[0006] To achieve the above objectives, the technical solutions adopted in the embodiments of this application are as follows: In a first aspect, embodiments of this application provide a height compensation method for a printing device, applied to a 3D printing device to be compensated in a height compensation system. The height compensation system includes: a first sensor assembly, a second sensor assembly, and the 3D printing device. The first sensor assembly is mounted on the nozzle mount assembly of the 3D printing device, and the second sensor assembly is mounted on or around the printing platform of the 3D printing device. The method includes: Determine the reference height corresponding to the preset measurement reference surface; the measurement reference surface is the sensing surface of the second sensor assembly; The printing nozzles in the 3D printing equipment are controlled to move sequentially to directly above the measurement reference surface and touch the measurement reference surface, and the height value of the printing nozzles when they touch the measurement reference surface is determined; Based on the height value of the print head when it touches the measuring reference surface and the reference height, the compensation height of the print head in the Z-axis direction is determined. Based on the compensation height of the print head in the Z-axis direction, the height of the print head is compensated in the Z-axis direction.

[0007] Optionally, the height compensation system includes a first sensor assembly mounted on the nozzle mount assembly of the 3D printing device.

[0008] Optionally, determining the reference height corresponding to the measurement reference plane includes: The nozzle assembly is controlled to move the first sensor assembly to a preset zero point on the printing platform, and the zero plane height corresponding to the zero point is determined based on the trigger signal of the first sensor assembly. The nozzle mount assembly is controlled to move the first sensor assembly directly above and into contact with the sensing surface of the second sensor assembly, and a first height value corresponding to the sensing surface is determined based on the trigger signal of the second sensor assembly when the first sensor assembly touches the sensing surface. Determine the first difference between the first height value and the zero plane height, and use the first difference as the reference height corresponding to the measurement reference surface.

[0009] Optionally, the 3D printing equipment is a multi-nozzle 3D printing equipment, which has multiple printing nozzles. Controlling the printing nozzles in the 3D printing equipment to sequentially move them directly above and into contact with the measurement reference surface, and determining the height value of the printing nozzle when it contacts the measurement reference surface, includes: After replacing the first print head in the multi-nozzle 3D printing device with the print head assembly, the print head assembly is controlled to move the first print head directly above the sensing surface of the second sensor assembly and make contact with the sensing surface. Based on the trigger signal of the second sensor assembly when the first print head touches the sensing surface, the height value of the print head when it touches the measurement reference surface is determined. This process is repeated several times until the height value of each print head when it touches the measurement reference surface is determined.

[0010] Optionally, determining the height value of the printhead when it touches the measurement reference surface based on the trigger signal of the second sensor assembly when the first printhead touches the sensing surface includes: The moving speed of the printhead assembly is obtained when the first printhead does not touch the sensing surface; Determine the signal trigger time difference of the second sensor component; Based on the moving speed of the printhead assembly and the signal trigger time difference, the response overshoot is determined. The response overshoot is used to characterize the displacement of the first printhead after it actually touches the sensing surface. The height value of the print head when it touches the measurement reference surface is corrected using the response overshoot, so as to obtain the actual height value of the print head when it touches the measurement reference surface.

[0011] Optionally, determining the signal trigger time difference of the second sensor component includes: When the first printhead does not touch the sensing surface, the reference signal output by the second sensor component is acquired, and a trigger threshold is set; The host control motion stops when the change in the output signal of the second sensor component exceeds the trigger threshold, and the peak time when the change in the output signal of the second sensor component reaches the maximum offset peak value is determined. The signal trigger time difference of the second sensor component is determined based on the peak time and the time when the host control motion stops.

[0012] Optionally, determining the compensation height of the printhead in the Z-axis direction based on the height value when the printhead touches the measuring reference surface and the reference height includes: Determine the second difference between the height value of the print head when it touches the measurement reference surface and the reference height, and use the second difference as the compensation height of the print head in the Z-axis direction.

[0013] Secondly, this application also provides a height compensation system for a printing device, the system comprising: a first sensor assembly, a second sensor assembly, and a multi-nozzle 3D printing device to be compensated, wherein the first sensor assembly and the second sensor assembly are both communicatively connected to the multi-nozzle 3D printing device; The first sensor assembly is mounted on the nozzle mount assembly of the multi-nozzle 3D printing equipment, and the second sensor assembly is mounted on the printing platform of the multi-nozzle 3D printing equipment. The multi-nozzle 3D printing equipment is used to perform the height compensation method steps of the printing equipment provided in the first aspect above.

[0014] Optionally, a sensor mounting base is provided at the bottom of the nozzle assembly, and the first sensor assembly is mounted on the sensor mounting base using a first fastener; The second sensor assembly is mounted to the zero plane of the printing platform using a second fastener.

[0015] Optionally, the second sensor assembly includes: a collision rod, an elastomer, an eddy current coil, an upper shell, and a lower shell, wherein the top surface of the collision rod is a sensing surface; The collision rod has a cylindrical or concave bowl-shaped structure; The middle part of the elastic body is grooved, the upper end of the elastic body is connected to the upper shell, the bottom of the elastic body is connected to the collision rod, and the bottom surface of the elastic body is positioned directly opposite the eddy current coil. The eddy current coil is fixedly bonded to the top inner surface of the lower shell, and the upper shell and the lower shell are connected to each other and together form an external encapsulation structure. One end of the second fixing member is detachably connected to the lower shell, and the other end of the fixing member is detachably connected to the printing platform, so that the lower shell is fixedly attached to the zero plane of the printing platform.

[0016] The beneficial effects of this application are: This application provides a height compensation method and system for a printing device. In this application, a preset reference height corresponding to a measurement reference surface is determined, and the printing nozzles in a multi-nozzle 3D printing device are controlled to sequentially move to directly above and contact the measurement reference surface. The height value of the printing nozzle when it contacts the measurement reference surface is determined, i.e., a unified measurement reference surface is established, allowing each printing nozzle to sequentially contact the measurement reference surface. Based on the trigger signal at the time of contact, the actual height deviation of each printing nozzle is measured. Based on the compensation height corresponding to the printing nozzle in the Z-axis direction, height compensation is performed on the printing nozzle in the Z-axis direction, achieving fully automatic leveling and first-layer optimization without manual intervention. This ensures the uniformity, adhesion, and flatness of the printed first layer, greatly improving the printing success rate and the level of equipment intelligence, and solving problems such as uneven first layer and low success rate in traditional multi-nozzle printing.

[0017] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 A schematic diagram of the architecture of a height compensation system for a printing device provided in this application embodiment; Figure 2 Schematic diagram of the nozzle holder assembly provided in the embodiments of this application Figure 1 ; Figure 3 Schematic diagram of the nozzle holder assembly provided in the embodiments of this application Figure 2 ; Figure 4 This is a schematic diagram showing the cylindrical shape of the collision rod in the second sensor assembly provided in this application embodiment; Figure 5 A schematic diagram showing the probe of the first sensor assembly provided in this application contacting the top surface of the elastomer; Figure 6 This is an overall schematic diagram of a height compensation system for a printing device provided in an embodiment of this application; Figure 7 A schematic flowchart illustrating a height compensation method for a printing device provided in an embodiment of this application; Figure 8 A schematic flowchart illustrating another height compensation method for a printing device provided in an embodiment of this application; Figure 9 This is a schematic diagram showing the first sensor assembly colliding with zero point A, as provided in an embodiment of this application. Figure 10 A schematic diagram showing the probe of the first sensor assembly touching the sensing surface of the second sensor assembly, as provided in an embodiment of this application. Figure 11 A schematic diagram showing the contact surface of the printhead touching the second sensor assembly, provided in an embodiment of this application; Figure 12 A schematic flowchart illustrating another height compensation method for a printing device provided in an embodiment of this application; Figure 13 A schematic flowchart illustrating another height compensation method for a printing device provided in an embodiment of this application; Figure 14 A schematic diagram of the output signal acquired from the second sensor component, provided for an embodiment of this application; Figure 15 This is a schematic diagram showing the compensation height of the print head in the Z-axis direction, provided for an embodiment of this application. Figure 16 A schematic diagram showing the height values ​​of each printhead when it touches the measurement reference surface, provided for an embodiment of this application; Figure 17 for Figure 6 A magnified view of a portion of the image; Figure 18 The collision rod in the sensor provided in this application embodiment is a concave "bowl-shaped" structure.

[0020] Icons: 1-First sensor assembly; 2-Second sensor assembly; 3-Multi-nozzle 3D printing equipment; 4-Nozzle holder assembly; 5-Printing platform; 6-Sensor mounting base; 7-Printing nozzle; 11-Sensor sensing sheet; 12-Sensor probe; 41-Nozzle holder base plate; 43-Electrical assembly; 44-Nozzle locking mechanism; 45-Air duct assembly; 21-Collision rod; 22-Elastomer; 23-Eddy current coil; 24-Upper shell; 25-Lower shell; 26-Mounting base; 27-Induction aluminum sheet. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0022] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0023] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this application, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0024] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0025] In the description of this application, it should be noted that the terms "upper", "lower", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship that the product of this application is usually placed in. 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.

[0026] In the description of this application, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0027] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0028] Please see Figure 1 , Figure 1 This application provides a schematic diagram of the architecture of a height compensation system for a printing device, as shown in the embodiments below. Figure 1 As shown, the height compensation system includes: a first sensor assembly 1, a second sensor assembly 2, and a multi-nozzle 3D printing device 3 to be compensated.

[0029] Both the first sensor assembly 1 and the second sensor assembly 2 are communicatively connected to the multi-nozzle 3D printing equipment 3.

[0030] For example, the first sensor assembly 1 is fixedly mounted on the nozzle mount assembly in the multi-nozzle 3D printing equipment 3.

[0031] The second sensor assembly 2 is an eddy current sensor. The second sensor assembly 2 is fixedly installed on the printing platform 5 or on the periphery of the printing platform, that is, the mounting surface of the second sensor assembly 2 is higher or lower than the plane of the printing platform 5.

[0032] In one feasible approach, the main control unit in a multi-nozzle 3D printing device can control the movement of the nozzle mount assembly to cause the first sensor assembly to touch the zero plane of the printing platform, and determine the zero plane height H0 of the printing platform based on the trigger signal of the first sensor assembly upon touch. Furthermore, the movement of the nozzle mount assembly can also be controlled to cause the first sensor assembly to touch the sensing surface of the second sensor assembly, and determine the sensing surface height H1 of the second sensor assembly based on the trigger signal of the second sensor assembly upon touch.

[0033] Then, printheads of different heights can be installed on the printhead mount assembly, and the movement of the printhead mount assembly can be controlled to drive the printhead to touch the sensing surface. Based on the trigger signal of the second sensor assembly when touching the sensing surface, the height H2 of the printhead touching the sensing surface is determined. Using the height H2 of the printhead touching the sensing surface and the height H1 of the sensing surface of the second sensor assembly previously calibrated, the height difference between the first sensor assembly and the printhead is measured, i.e., Z1 = H2 - H1, which is the compensation height of the printhead in the Z-axis direction. This allows for subsequent compensation of the printhead in the Z-axis direction based on the compensation height of the printhead in the Z-axis direction. In this way, it can be ensured that the distance between the nozzle tip and the surface of the printing platform (i.e., the first layer gap) of the printhead is precisely consistent before printing begins, thereby achieving flat, uniform, and reliable first layer printing, improving the printing success rate and printing quality.

[0034] Understandable. Figure 1 The structure shown is for illustrative purposes only; the height compensation system of the printing equipment may also include components that are more advanced than those shown. Figure 1 The more or fewer components shown, or having the same Figure 1 The different configurations shown. Figure 1 The components shown can be implemented using hardware, software, or a combination thereof.

[0035] Optionally, refer to Figures 2-3 The diagram shown is a structural schematic of the nozzle holder assembly in the multi-nozzle 3D printing equipment provided in this application. Figure 2 As shown, the nozzle holder assembly 4 includes a nozzle holder base plate 41 and a sensor mounting base 6. The sensor mounting base 6 is located at the bottom of the nozzle holder assembly. The first sensor assembly 1 is installed on the sensor mounting base 6 using a first fastener (such as a screw, clip, or pressure plate) to prevent loosening or displacement caused by factors such as vibration, thermal expansion and contraction.

[0036] Among them, such as Figure 2 As shown, the first sensor assembly 1 includes: sensor sensing element 11 and sensor probe 12, etc. The first sensor assembly 1 is not limited to eddy current sensor, strain gauge sensor, and proximity switch.

[0037] Optionally, such as Figure 6 As shown, the second sensor assembly 2 is installed on the printing platform 5 using a second fastener (such as a screw, magnetic assembly, snap-fit ​​structure or adhesive). It can be set on the inner edge of the printing platform 5 or on the outer periphery of the printing platform 5.

[0038] Continue to refer to Figure 3 As shown, the nozzle mount assembly 4 also includes: electrical assembly 43, nozzle locking mechanism 44, air duct assembly 45, etc., wherein the nozzle locking mechanism 44 is used to lock the printing nozzle in the multi-nozzle 3D printing equipment.

[0039] Optionally, refer to Figure 4 The diagram shown is a schematic representation of the cylindrical collision rod in the second sensor assembly provided in this embodiment of the application. Figure 4 As shown, the second sensor assembly 2 includes: a collision rod 21, an elastic body 22, an eddy current coil 23, an upper shell 24, and a lower shell 25.

[0040] in, Figure 4 The diagram shows a schematic of the print head 7 touching the sensing surface of the second sensor assembly.

[0041] The collision rod 21 is cylindrical, with a spherical or planar contact head at its top. The top surface of the collision rod is the sensing surface of the second sensor assembly, used to achieve point or surface contact with the probe or printhead of the first sensor assembly.

[0042] The middle part of the elastomer 22 is grooved. The elastomer 22 is made of metal material, and the groove of the material in the middle part is removed to reduce stiffness and increase deformation sensitivity. The upper end of the elastomer 22 is connected to the upper shell 24, and the bottom of the elastomer 22 is connected to the collision rod 21. The bottom surface of the elastomer 22 is positioned directly opposite the eddy current coil 23. A sensing gap of 0.1 to 0.4 mm is maintained between the bottom surface of the elastomer 22 and the eddy current coil 23 to balance sensitivity and anti-interference capability.

[0043] Eddy current coil 23 is fixedly bonded to the top inner surface of lower shell 25. Upper shell 24 and lower shell 25 are interconnected and together form the external encapsulation structure. Eddy current coil 23 is used to output an impedance signal (or frequency signal) that changes with the air gap, thereby determining whether a contact event has occurred. (See reference...) Figure 5 As shown, when the probe of the first sensor assembly touches the top surface of the elastomer, it causes the elastomer 22 to deform, thereby changing the air gap between its bottom surface and the eddy current coil 23, triggering the second sensor assembly to output a signal to confirm the contact event.

[0044] One end of the second fixing member is detachably connected to the lower shell, and the other end of the second fixing member is detachably connected to the printing platform, so that the lower shell is fixedly attached to the printing platform. That is, the lower shell of the second sensor assembly is fixedly connected to the zero plane of the printing platform through the second fixing member, so as to achieve a reliable connection and improve the accuracy of the measurement results.

[0045] Optionally, refer to Figure 6 The diagram shown is a schematic of a height compensation system for a printing device provided in an embodiment of this application. Figure 6 As shown, the first sensor assembly 1 is fixed to the bottom of the nozzle holder assembly 4 and the sensor probe 12 protrudes from the nozzle holder assembly 4. The second sensor assembly 2 is fixedly connected to the zero plane of the printing platform 5. In this way, the compensation height of the printing nozzle can be measured by the trigger signals of the first sensor assembly and the second sensor assembly, thereby improving the printing effect of the multi-nozzle 3D printing equipment and ensuring the success rate of the printed model.

[0046] The specific implementation steps of the height compensation method for the printing device provided in this application will be described through the following embodiments.

[0047] Optionally, refer to Figure 7 The diagram shown is a flowchart illustrating a height compensation method for a printing device according to an embodiment of this application. The main controller of this method is the main control unit in the multi-nozzle 3D printing device to be compensated. Figure 7 As shown, the method includes: S101. Determine the reference height corresponding to the preset measurement reference surface.

[0048] The measurement reference plane is a physically fixed, precisely positioned, and repeatedly accessible spatial reference plane; the reference height refers to the standard position value of the measurement reference plane in the Z-axis coordinate system.

[0049] For example, the measurement reference surface can be the sensing surface of the second sensor assembly, that is, the height value of the sensing surface can be used as the reference height H1.

[0050] For example, the measurement reference surface can also be a flat area calibrated on the printing platform. The reference height of the measurement reference surface is obtained by laser ranging or multiple average measurements and stored in the control system to provide a "zero point" reference for all printheads to compare together, avoiding the lack of a unified standard for comparison between different printheads.

[0051] S102. Control the printing nozzles in the multi-nozzle 3D printing equipment to move sequentially to directly above the measurement reference surface and touch the measurement reference surface, and determine the height value of the printing nozzle when it touches the measurement reference surface.

[0052] Multi-nozzle 3D printing equipment includes multiple printing nozzles, each with a different height. Therefore, it is necessary to determine the height of each printing nozzle individually.

[0053] In one feasible approach, the main controller of a multi-nozzle 3D printing device can control the printing nozzles to move sequentially to directly above the measurement reference surface, and control the printing nozzles to slowly descend or the printing platform to slowly rise until the tip of the printing nozzle actually touches the measurement reference surface. At this point, the second sensor component will output a trigger signal, and based on the trigger signal, calculate the height value H2 of the printing nozzle when it touches the measurement reference surface, that is, obtain the actual height data of the printing nozzle relative to the measurement reference surface.

[0054] S103. Based on the height value of the print head when it touches the measurement reference surface and the reference height, determine the compensation height of the print head in the Z-axis direction.

[0055] The compensation height of the printhead in the Z-axis direction is used to characterize the height difference between the tip of the printhead and the "printing platform" in the Z-axis direction.

[0056] S104. Based on the compensation height of the print head in the Z-axis direction, perform height compensation on the print head in the Z-axis direction.

[0057] In one feasible approach, to ensure the quality of the first layer printing in a multi-nozzle 3D printing device, it is necessary to ensure that the height difference between each printing nozzle and the platform surface is consistent. Therefore, this embodiment proposes to calculate the compensation height of the printing nozzle in the Z-axis direction based on the height value when the printing nozzle touches the reference surface and the reference height. Based on the compensation height of the printing nozzle in the Z-axis direction, the height of the printing nozzle in the Z-axis direction is compensated, achieving "on-demand adjustment" without relying on manual leveling. At the same time, it can also eliminate the height difference between printing nozzles, achieving μm-level Z-axis consistency. This ensures that regardless of which printing nozzle is used, the first layer material can adhere to the platform with the same and optimal pressure, achieving true "seamless switching" multi-color / multi-material printing. This solves the problems of uneven first layer and low success rate in traditional multi-head printing.

[0058] Therefore, in this application, by establishing a unified measurement reference plane, each print head is allowed to contact the measurement reference plane in sequence, and the actual height deviation of each print head is measured based on the trigger signal at the time of contact. A personalized Z-axis compensation height is calculated and automatically used during printing, thereby ensuring that all print heads have a consistent and ideal nozzle-platform gap during the first layer of printing, thus improving the multi-head printing effect.

[0059] In summary, this application provides a height compensation method for a printing device. In this application, a reference height corresponding to a preset measurement reference surface is determined, and the printing nozzles in a multi-nozzle 3D printing device are controlled to sequentially move to directly above and contact the measurement reference surface. The height value of the printing nozzle when it contacts the measurement reference surface is determined, i.e., a unified measurement reference surface is established, allowing each printing nozzle to sequentially contact the measurement reference surface. Based on the trigger signal at the time of contact, the actual height deviation of each printing nozzle is measured. Furthermore, based on the compensation height corresponding to the printing nozzle in the Z-axis direction, height compensation is performed on the printing nozzle in the Z-axis direction, achieving fully automatic leveling and first-layer optimization without manual intervention. This ensures the uniformity, adhesion, and flatness of the printed first layer, greatly improving the printing success rate and the device's intelligence level, and solving problems such as uneven first layer and low success rate in traditional multi-nozzle 3D printing devices.

[0060] Optionally, the measurement reference surface is the sensing surface of the second sensor assembly.

[0061] The sensing surface of the second sensor assembly refers to the physical contact surface that directly responds to external touch. Specifically, it is the top plane of the collision rod of the second sensor assembly, and also the trigger point for changes in the air gap between the elastic body and the eddy current coil within the second sensor assembly. In other words, the sensing surface of the second sensor assembly is a flat, rigid surface, ensuring consistency in each contact.

[0062] In one feasible approach, the second sensor assembly is securely mounted to the printing platform by a second fastener (such as a screw or pin), meaning that the spatial coordinates of the sensing surface of the second sensor assembly remain almost unchanged. This allows all printheads to use the sensing surface of the second sensor assembly as a reference, eliminating the accumulation of relative errors and ensuring consistent results.

[0063] It should be noted that in this embodiment, the sensing surface of the second sensor component is selected as the measurement reference surface. This is not a simple position setting, but rather a high-precision leveling reference system that integrates physical reference, electrical feedback, and repeatable triggering to meet the requirements of repeatable positioning accuracy.

[0064] Optionally, refer to Figure 8 As shown, step S101 above includes: S201. Control the printhead assembly to move the first sensor assembly to a preset zero point on the printing platform, and determine the zero plane height corresponding to the zero point based on the trigger signal of the first sensor assembly.

[0065] The preset zero point can be the center point of the printing platform or any other point on the printing platform.

[0066] In one feasible approach, the printhead assembly is controlled to move the first sensor assembly to a preset zero point A on the printing platform. At this point, the first sensor assembly contacts the zero point A, and based on the trigger signal output by the first sensor assembly, the zero-plane height H0 corresponding to the zero point A is determined and recorded as 0. Figure 9 As shown.

[0067] Therefore, in this embodiment, the first sensor assembly installed on the nozzle seat assembly is used as a "detection tool". The Z-axis coordinate value at the time when the first sensor assembly contacts the zero point A is recorded using the trigger signal, and is denoted as the zero plane height H0.

[0068] S202, control the nozzle seat assembly to move the first sensor assembly to directly above and in contact with the sensing surface of the second sensor assembly, and determine the first height value corresponding to the sensing surface based on the trigger signal of the second sensor assembly when the first sensor assembly touches the sensing surface.

[0069] In one feasible approach, the nozzle mount assembly is controlled to move the first sensor assembly directly above the sensing surface of the second sensor assembly, and then slowly descends until the first sensor assembly contacts the sensing surface (i.e., the impact rod). Based on the trigger signal of the second sensor assembly when the first sensor assembly contacts the sensing surface, a first height value H1 corresponding to the sensing surface is determined, such as... Figure 10 As shown, the first height value H1 is the height position of the nozzle assembly.

[0070] It should be noted that in this measurement process, the trigger signal of the second sensor component is used to determine the contact time, rather than relying on the trigger signal of the first sensor component to prevent the error transmission of the first sensor component.

[0071] S203. Determine the first difference between the first height value and the zero plane height, and use the first difference as the reference height corresponding to the measurement reference plane.

[0072] In one possible implementation, a first difference between a first height value H1 and a zero plane height H0 can be calculated, and this first difference can be used as a reference height corresponding to the measurement reference plane. This reference height is used as a reference value for leveling all printheads.

[0073] Optionally, the 3D printing equipment is a multi-nozzle 3D printing equipment, which has multiple printing nozzles. Step S102 above includes: After replacing the first print head in the multi-nozzle 3D printing equipment with the print head assembly, the print head assembly is controlled to move the first print head directly above and into contact with the sensing surface of the second sensor assembly. Based on the trigger signal of the second sensor assembly when the first print head touches the sensing surface, the height value of the print head touching the measurement reference surface is determined. This process is repeated several times until the height value of each print head touching the measurement reference surface is determined.

[0074] In one feasible approach, the first printhead is replaced with a printhead mount assembly, and the printhead mount assembly is controlled to move the first printhead directly above the sensing surface of the second sensor assembly. The first printhead is then slowly lowered, or the printing platform is slowly raised, until the tip of the first printhead contacts the sensing surface of the second sensor assembly. At this point, the trigger signal output by the second sensor assembly when the first printhead contacts the sensing surface is recorded. Based on this trigger signal, the height value H2 of the printhead when it contacts the measurement reference surface is calculated. Figure 11 As shown.

[0075] Optionally, refer to Figure 12 As shown, the height value H2 when the printhead touches the measurement reference surface is calculated based on the trigger signal of the second sensor assembly when the first printhead touches the sensing surface, including: S301. Obtain the moving speed of the printhead assembly when the first printhead is not touching the sensing surface.

[0076] The moving speed of the nozzle assembly is measured during the uniform speed phase just before contact, to avoid acceleration / deceleration interfering with the calculation accuracy.

[0077] S302. Determine the signal trigger time difference of the second sensor component.

[0078] S303. Determine the response overshoot based on the moving speed of the nozzle assembly and the signal trigger time difference.

[0079] The response overshoot is used to characterize the displacement of the first print head after it actually touches the sensing surface, that is, the distance the print head travels between the time it actually touches the measurement reference surface and the time when the print head stops moving.

[0080] S304. Correct the height value of the print head when it touches the measurement reference surface using the response overshoot to obtain the actual height value of the print head when it touches the measurement reference surface.

[0081] In one feasible approach, considering the problem of "overshoot displacement" caused by the sensor's response delay, which results in the sensor not outputting a trigger signal in time after being actually triggered, this application proposes that the measured height value can also be corrected.

[0082] Specifically, the moving speed s0 of the printhead assembly when the first printhead is not touching the sensing surface is obtained, and the signal triggering time difference Δt1 of the second sensor assembly is determined. The product of the moving speed s0 and the signal triggering time difference Δt1 of the second sensor assembly is calculated, i.e., Δd = s0 * Δt 1， The product of the moving speed s0 and the signal trigger time difference Δt1 of the second sensor component is used as the response overshoot. Then, the height value when the print head touches the measurement reference surface is corrected using the response overshoot to obtain the actual height value when the print head touches the measurement reference surface, that is, to obtain the true height value when the print head touches the measurement reference surface.

[0083] Optionally, refer to Figure 13 As shown, step S302 above includes: S401. When the first printhead does not touch the sensing surface, acquire the reference signal output by the second sensor assembly and set the trigger threshold.

[0084] For example, the trigger threshold can be set to h0 ± Δh0. Here, the output signal h0 of the second sensor assembly when the first printhead is not in contact with the sensing surface is the normal value; and the difference between the trigger threshold and the normal value is set to Δh0.

[0085] S402. Determine the moment when the change in the output signal of the second sensor component exceeds the trigger threshold and the moment when the change in the output signal of the second sensor component reaches the peak value of the maximum offset peak.

[0086] The host control motion stops at time t0, and the peak time is t.

[0087] S403. Determine the signal trigger time difference of the second sensor component based on the peak time and the time when the host control stops the motion.

[0088] In one feasible way, such as Figure 14 The diagram shows the output signal collected from the second sensor component. When the first print head does not touch the sensing surface, the output signal h0 of the second sensor component is at a normal value. When the first print head touches the sensing surface, the change value measured by the second sensor component exceeds the trigger threshold, and the first print head stops moving. However, due to the system communication delay, it will not stop instantly. Therefore, it will move a certain distance, that is, the output signal value will reach the peak hmin. Thus, the difference between the peak value and the normal value Δh1, the host control movement stop time t0 and the peak time t1 are obtained. Therefore, the time difference between the peak time t1 and the host control movement stop time t0 can be obtained, that is, Δt1=t1-t0.

[0089] Optionally, step S103 above includes: Determine the second difference between the height of the print head when it touches the measurement reference surface and the reference height, and use the second difference as the compensation height of the print head in the Z-axis direction.

[0090] In one feasible approach, refer to Figure 15 As shown, the compensation height of the print head in the Z-axis direction is the difference between the height of the print head when it touches the measurement reference surface and the reference height. This second difference is used as the compensation height Z1 of the print head in the Z-axis direction.

[0091] Optionally, such as Figure 16 The figure shows the height values ​​of each printhead when it touches the measurement reference surface. For example, the height value of the second printhead when it touches the measurement reference surface is H3.2, the height value of the third printhead when it touches the measurement reference surface is H3.3, and the height value of the fourth printhead when it touches the measurement reference surface is H3.4. That is, by repeating the above method several times, the height value of each printhead when it touches the measurement reference surface can be obtained.

[0092] Similarly, the height value when the first sensor component touches the sensing surface of the second sensor component is also calculated using the method described above.

[0093] Optionally, refer to Figure 17 The image shown is a partially enlarged schematic diagram of a height compensation system for a printing device provided in an embodiment of this application; as shown... Figure 17 As shown, the second sensor assembly 2 is fixedly mounted on the printing platform 5 of the multi-nozzle 3D printing equipment, such as being set at the edge inside the printing platform 5.

[0094] Alternatively, in another possible implementation, refer to Figure 18 As shown, the upper part of the collision rod 21 in the second sensor is a concave "bowl-shaped" structure (similar to a hemispherical, inverted frustum, or shallow basin shape), with the opening facing upwards. The bottom of the "bowl" is connected to the elastic body 22, and the overall deformation transmission path remains unchanged. That is, the bottom or side surface of the collision rod 21 is the sensing surface of the second sensor, used to achieve point or surface contact with the probe or printhead of the first sensor assembly.

[0095] The print head can first touch the inner bottom of the "bowl" for Z-axis calibration; or the print head can slide in from the upper side / side and contact a point on the edge of the "bowl" for X / Y-axis calibration.

[0096] Continue to refer to Figure 18As shown, the second sensor assembly 2 also includes: a mounting base 26 and a sensing aluminum sheet 27, which can be used to mount the second sensor assembly to the printing platform; and when the print head touches the bottom of the collision rod 21, it causes the elastic body 22 to deform, thereby changing the air gap between its sensing aluminum sheet 27 and the eddy current coil 23, triggering the second sensor assembly 2 to output a signal to confirm the contact event.

[0097] Optionally, this application also provides a program product, such as a computer-readable storage medium, including a program that, when executed by a processor, performs the above-described method embodiments.

[0098] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

[0099] It will be apparent to those skilled in the art that this application is not limited to the details of the exemplary embodiments described above, and that this application can be implemented in other specific forms without departing from the spirit or essential characteristics of this application. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this application is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this application. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A height compensation method for a printing device, characterized in that, A 3D printing device to be compensated in a height compensation system, the height compensation system comprising: a second sensor assembly and the 3D printing device, the second sensor assembly being mounted on or around the printing platform of the 3D printing device, the method comprising: Determine the reference height corresponding to the preset measurement reference surface; the measurement reference surface is the sensing surface of the second sensor assembly; The printing nozzle in the 3D printing device is controlled to move directly above the measurement reference surface and touch the measurement reference surface, and the height value of the printing nozzle when it touches the measurement reference surface is determined; Based on the height value of the print head when it touches the measuring reference surface and the reference height, the compensation height of the print head in the Z-axis direction is determined. Based on the compensation height of the print head in the Z-axis direction, the height of the print head is compensated in the Z-axis direction.

2. The method according to claim 1, characterized in that, The height compensation system includes a first sensor assembly mounted on the nozzle mount assembly of the 3D printing equipment.

3. The method according to claim 2, characterized in that, Determining the reference height corresponding to the measurement reference surface includes: The nozzle assembly is controlled to move the first sensor assembly to a preset zero point on the printing platform, and the zero plane height corresponding to the zero point is determined based on the trigger signal of the first sensor assembly. The nozzle mount assembly is controlled to move the first sensor assembly directly above and into contact with the sensing surface of the second sensor assembly, and a first height value corresponding to the sensing surface is determined based on the trigger signal of the second sensor assembly when the first sensor assembly touches the sensing surface. Determine the first difference between the first height value and the zero plane height, and use the first difference as the reference height corresponding to the measurement reference surface.

4. The method according to claim 2, characterized in that, The 3D printing equipment is a multi-nozzle 3D printing equipment, which has multiple printing nozzles. Controlling the printing nozzles in the 3D printing equipment to move directly above and contact the measurement reference surface, and determining the height value of the printing nozzle when it contacts the measurement reference surface, includes: After replacing the first printhead in the multi-nozzle 3D printing device with the printhead mount assembly, the printhead mount assembly is controlled to move the first printhead directly above the sensing surface of the second sensor assembly and into contact with the sensing surface. Based on the trigger signal of the second sensor assembly when the first printhead touches the sensing surface, the height value of the first printhead when it touches the measurement reference surface is determined. This process is repeated several times until the height value of each printhead when it touches the measurement reference surface is determined.

5. The method according to claim 4, characterized in that, The determination of the height value when the printhead touches the measurement reference surface based on the trigger signal of the second sensor component when the first printhead touches the sensing surface includes: The moving speed of the printhead assembly is obtained when the first printhead does not touch the sensing surface; Determine the signal trigger time difference of the second sensor component; Based on the moving speed of the printhead assembly and the signal trigger time difference, the response overshoot is determined. The response overshoot is used to characterize the displacement of the first printhead after it actually touches the sensing surface. The height value of the print head when it touches the measurement reference surface is corrected using the response overshoot, so as to obtain the actual height value of the print head when it touches the measurement reference surface.

6. The method according to claim 5, characterized in that, Determining the signal trigger time difference of the second sensor component includes: When the first printhead does not touch the sensing surface, the reference signal output by the second sensor component is acquired, and a trigger threshold is set; The host control motion stops when the change in the output signal of the second sensor component exceeds the trigger threshold, and the peak time when the change in the output signal of the second sensor component reaches the maximum offset peak value is determined. The signal trigger time difference of the second sensor component is determined based on the peak time and the time when the host control motion stops.

7. The method according to claim 1, characterized in that, The determination of the compensation height of the printhead in the Z-axis direction based on the height value when the printhead touches the measuring reference surface and the reference height includes: Determine the second difference between the height value of the print head when it touches the measurement reference surface and the reference height, and use the second difference as the compensation height of the print head in the Z-axis direction.

8. A height compensation system for a printing device, characterized in that, The system includes: a first sensor assembly, a second sensor assembly, and a multi-nozzle 3D printing device to be compensated, wherein the first sensor assembly and the second sensor assembly are both communicatively connected to the multi-nozzle 3D printing device; The first sensor assembly is mounted on the nozzle mount assembly of the multi-nozzle 3D printing equipment, and the second sensor assembly is mounted on the printing platform of the multi-nozzle 3D printing equipment or on the periphery of the printing platform. The multi-nozzle 3D printing equipment is used to perform the height compensation method steps of the printing equipment according to any one of claims 1-7.

9. The system according to claim 8, characterized in that, The nozzle holder assembly is provided with a sensor mounting base at its bottom, and the first sensor assembly is mounted on the sensor mounting base using a first fastener. The second sensor assembly is mounted to the printing platform using a second fastener.

10. The system according to claim 9, characterized in that, The second sensor assembly includes: a collision rod, an elastomer, an eddy current coil, an upper shell, and a lower shell, wherein the top surface of the collision rod is a sensing surface; The collision rod has a cylindrical or concave bowl-shaped structure; The middle part of the elastic body is grooved, the upper end of the elastic body is connected to the upper shell, the bottom of the elastic body is connected to the collision rod, and the bottom surface of the elastic body is positioned directly opposite the eddy current coil. The eddy current coil is fixedly bonded to the top inner surface of the lower shell, and the upper shell and the lower shell are connected to each other and together form an external encapsulation structure. One end of the second fixing member is detachably connected to the lower shell, and the other end of the fixing member is detachably connected to the printing platform, so that the lower shell is fixedly attached to the printing platform.

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