A forming table detection device and usage method for a light-curing 3D printing device

Abstract

The present invention discloses a forming table detection device and a usage method for a photo-curing 3D printing device. The detection device takes the photo-curing occurrence plane as the reference plane and includes a control system and a detection unit. The detection unit includes a transmission member and a contact sensor. The transmission member is connected to a power source. The detection device has at least three contact sensors. The contacts of the contact sensors are all located on a plane parallel to the reference plane. The contacts of the contact sensors have a displaceable travel distance in the direction perpendicular to the reference plane. The control system can read the travel distance of the contacts. The detection device realizes the full-automatic detection of the flatness of the forming surface of the forming table. By the control system issuing an instruction to the power source, the power source starts the transmission member, realizing the translation in and out of the contact sensor within the spatial area covered by the displacement on the forming table, without affecting the subsequent printing operation of the photo-curing 3D printing device, and the detection process is convenient to operate.

Description

Technical Field

[0001] The present invention relates to the additive manufacturing industry, and more specifically, to a forming table detection device for a stereolithography 3D printing device and a usage method thereof. Background Art

[0002] Stereo Lithography Appearance (SLA or SL) 3D printing is a type of 3D printing that mainly uses photosensitive resin as the raw material and utilizes the characteristic that liquid photosensitive resin rapidly cures under the irradiation of an ultraviolet laser beam. The photosensitive resin is generally in a liquid state, and it rapidly undergoes a polymerization reaction under the irradiation of ultraviolet light with a certain wavelength (250nm - 400nm) to complete curing.

[0003] The specific process of Stereo Lithography 3D printing is as follows: First, the three-dimensional model of the pre-print is sliced into layers. Then, by irradiating the surface of the photosensitive resin (i.e., the plane where the stereolithography occurs), it is cured into a thin layer of solid. The cured photosensitive resin is the pattern of each layer slice. The already cured part is attached to the forming surface of the forming table. The forming table is connected to a motion mechanism and can be displaced in a direction perpendicular to the plane where the stereolithography occurs, thereby driving the cured part to be separated from the plane where the stereolithography occurs by a certain distance (usually a dozen micrometers each time). Then, on the basis of the cured resin of the previous layer, the next layer is irradiated and cured. After layer-by-layer curing and stacking, a complete printed part is finally formed.

[0004] During the printing process, the forming surface of the forming table is used to attach the printed part. Therefore, the flatness error value of the forming surface of the forming table is a key point affecting the printing effect. Since the forming surface of the forming table attaches the printed part, the forming table is generally a platform-type structure with a large surface area. The forming surface of the forming table has high precision requirements and is difficult to process. When the forming table is installed in a 3D printing device and is used for the first time, it is necessary to first detect the forming table to determine whether the flatness error value of the forming surface of the forming table meets the printing requirements. There is no suitable detection device in the prior art. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a forming table detection device for a stereolithography 3D printing device, which can realize automatic detection and accurately judge whether the flatness of the forming surface of the forming table meets the printing requirements of the 3D printing device.

[0006] To solve the above technical problems, the present invention provides a forming table detection device for a stereolithography 3D printing device. The stereolithography plane of the stereolithography 3D printing device is the reference plane of this detection device. This detection device detects the flatness of the forming surface of the forming table based on the reference plane. The detection device includes a control system and one or more detection units. The detection unit includes a transmission member and one or more contact sensors. The transmission member is connected to a power source, and the control system controls the opening and closing of the power source. The detection device has at least three contact sensors. The contacts of the contact sensors are all located on a plane parallel to the reference plane. The contacts of the contact sensors have a displaceable travel distance in the direction perpendicular to the reference plane. The control system can read the travel distance of the contacts. When the detection device is detecting, the control system controls the power source to drive the transmission member, so that all the contact sensors are translated in a plane parallel to the reference plane into the spatial area covered by the displacement of the forming table in the direction perpendicular to the reference plane. When the detection device finishes detecting, the power source drives the transmission member, so that all the contact sensors are translated in a plane parallel to the reference plane out of the spatial area covered by the displacement of the forming table in the direction perpendicular to the reference plane.

[0007] After adopting the above structure, compared with the prior art, the present invention has the following advantages: The forming table detection device of this stereolithography 3D printing device realizes the full-automatic detection of the flatness of the forming surface of the forming table. By the control system issuing an instruction to the power source, the power source starts the transmission member, realizing the translation of the contact sensors in and out of the spatial area covered by the displacement of the forming table, without affecting the subsequent printing operation of the stereolithography 3D printing device, and the detection process is convenient to operate.

[0008] Further, a threshold value of the flatness of the forming surface of the forming table is input into the control system. When the detection device is detecting, the forming table is displaced in the direction perpendicular to the reference plane towards the direction close to the contact sensors. During the displacement process, the contact sensors contact the forming surface of the forming table in a certain order respectively. When all the contact sensors are in contact with the forming surface of the forming table, each contact sensor feeds back the displacement travel distance of its contact in the direction perpendicular to the reference plane to the control system. The maximum value in this travel distance is the error value of the flatness of the forming surface of the forming table. Compare this error value with the threshold value of the flatness of the forming surface of the forming table, and determine whether the flatness of the forming surface of the forming table is qualified according to the preset standard.

[0009] Further, the detection device is connected with an alarm. The alarm is connected to the control system. When the detection result of the forming table detection is unqualified, the control system outputs an instruction and the alarm gives an alarm.

[0010] Further, the contact sensors are translated into the spatial area covered by the displacement of the forming table, and the connecting wires of all the contact sensors form a regular polygon.

[0011] Further, the contact sensors are translated into the spatial area covered by the displacement of the forming table, and at least one contact sensor is located in the central part of the spatial area.

[0012] Further, the power source is a motor, and the transmission parts are interlocked with each other and connected to the motor.

[0013] Further, the transmission parts include shafts, bearings and connectors, and the connectors are respectively connected to the shafts and the contact sensors.

[0014] Further, the transmission parts are interlocked through belts or connecting rods, or the shafts are interlocked through belts or connecting rods.

[0015] Further, the connector is strip-shaped, one end of the connector is provided with a contact sensor, and the other end of the connector is sleeved on the shaft and interlocked with the shaft.

[0016] Further, the length of the connector is adjustable according to the surface area of the measured forming table.

[0017] Further, when the detection device is detecting, the position reached by the contact sensor during translation on a plane parallel to the reference plane is adjustable.

[0018] Further, the detection device may further include one or more detection units that only contain transmission parts.

[0019] Further, the transmission part is connected to a magnetic base, and the magnetic base is directly in contact with the stereolithography 3D printing device.

[0020] For the above-mentioned forming table detection device for a stereolithography 3D printing device, with the stereolithography occurrence plane as the reference plane, the flatness detection method for detecting the forming surface of the forming table based on the reference plane includes:

[0021] Step a: After the stereolithography 3D printing device is installed, install the detection device on the stereolithography 3D printing device. The contact surfaces of the contact sensors are all located on a plane parallel to the 3D printing reference plane, and input the flatness threshold of the forming surface of the forming table into the control system of the detection device;

[0022] Step b: Start the detection device of the stereolithography 3D printing device. The control system controls the power source to start all the transmission parts, so that all the contact sensors are translated into the spatial area covered by the displacement of the forming table in the direction perpendicular to the reference plane on a plane parallel to the reference plane, and adjust the position of each contact sensor;

[0023] Step c: The forming table starts to displace in a direction perpendicular to the reference plane towards the contact sensor. During the displacement process, the contact sensors contact the forming surface of the forming table in a certain order. When all the contact sensors are in contact with the forming surface of the forming table, each contact sensor feeds back the displacement travel distance of its contact point in the direction perpendicular to the reference plane to the control system.

[0024] Step d: The control system compares the displacement travel distances of each contact point. The maximum value of the travel distance is the flatness error value of the forming surface of the forming table. This error value is compared with the flatness threshold of the forming surface of the forming table, and it is determined whether the flatness of the forming table is qualified according to the preset standard.

[0025] Further, according to the detection result of the control system in step d, if the detection result is qualified, the control system activates the power source, and the power source activates all transmission parts, so that all contact sensors are translated out of the space area covered by the displacement of the forming table.

[0026] Further, the detection device is connected with an alarm, and the alarm is connected to the control system. When the detection result in step d is unqualified, the control system outputs an instruction and the alarm gives an alarm.

[0027] Further, the flatness threshold of the forming surface of the forming table in step a is adjustable according to the size of the forming surface area of the forming table.

[0028] Further, the detection method can repeat steps b, c, and d for at least one recheck. For each detection, the positions of all contact sensors after they are translated into the space area covered by the displacement of the forming table in step b are different from the positions of the contact sensors in the previous step b.

[0029] Further, when the contact sensors are translated into the space area covered by the displacement of the forming table in step b, the connecting lines of all the contact sensors form a regular polygon.

[0030] Further, when the contact sensors are translated into the space area covered by the displacement of the forming table in step b, at least one contact sensor is located in the central part of the space area. Description of the Drawings

[0031] Figure 1 is a schematic structural diagram of the stereolithography 3D printing device in the present invention;

[0032] Figure 2 is a schematic partial structural diagram of the stereolithography 3D printing device in the present invention;

[0033] Figure 3 is a schematic structural diagram of the detection device in the present invention;

[0034] Figure 4 is a schematic structural diagram of a detection unit in some embodiments of the present invention;

[0035] Figure 5 is a schematic diagram of the positional relationship between a contact sensor and the spatial region covered by the displacement of a forming table in the present invention;

[0036] Figure 6 is a schematic diagram of the position of a contact sensor within the spatial region covered by the displacement of a forming table in the present invention;

[0037] Figure 7 is another schematic diagram of the position of a contact sensor within the spatial region covered by the displacement of a forming table in the present invention.

[0038] Wherein: 1. Stereolithography 3D printing device; 1.1. Forming table; 1.11. Forming surface of the forming table; 1.2. Material box; 1.3. Optical machine; 1.4. Operating table; 1.5. Stereolithography occurrence plane; 2. Detection device; 2.1. Detection unit; 2.11. Shaft; 2.12. Bush; 2.13. Connecting member; 2.14. Contact sensor; 2.141. Contact; 2.2. Power source; 2.3. Magnetic base; 2.4. Linking member; 2.5. Control system. Specific embodiments

[0039] The present invention will be further described in detail below in conjunction with specific embodiments.

[0040] It should be understood that when an element is referred to as being "on", "attached to", "connected to", "combined with", "in contact with", etc. another element, it can be directly on, attached to, connected to, combined with and / or in contact with the other element or there may also be intermediate elements. In contrast, when an element is referred to as being "directly on", "directly attached to", "directly connected to", "directly combined with" or "directly in contact with" another element, there are no intermediate elements. Those skilled in the art will also understand that a structure or member referred to as being "adjacent" to another member may have portions that overlap or are located under the adjacent member.

[0041] Spatial-related terms, such as "below", "beneath", "lower", "above", "upper", etc., may be used in this document for ease of description to describe the relationship between an element or component shown in the accompanying drawings and one or more other elements or components. It is to be understood that spatial-related terms are intended to include different orientations of the device during use or operation in addition to the orientation depicted in the accompanying drawings. For example, if the device in the accompanying drawings is inverted, an element described as "below" or "beneath" other elements or components will be oriented "above" the other elements or components. Thus, the exemplary term "below" can include both upward and downward orientations. The device can be oriented in other ways (rotated 90 degrees or other orientations) and the spatial-related descriptive terms used herein are to be interpreted accordingly. Similarly, unless explicitly indicated otherwise, terms such as "upward", "downward", "vertical", "horizontal", etc. are used herein for illustrative purposes only.

[0042] As Figure 1 , Figure 2 shown, the light-curing 3D printing device 1 includes a frame. A forming platform 1.1, a material box 1.2 with a light-transmissive bottom surface, and a light machine 1.3 are connected to the frame from top to bottom. The raw materials for 3D printing are photosensitive resin and photoinitiator. The photoinitiator causes the photosensitive resin to cure when exposed to light of a certain wavelength. The cured resin layer adheres to the forming surface 1.5 of the forming platform 1.1. During printing, the photosensitive resin is injected into the material box 1.2, and the light from the light machine 1.3 irradiates the photosensitive resin on the bottom surface of the material box 1.2. The irradiated part of the photosensitive resin undergoes photocuring, and the plane 1.5 where the photocuring of the photosensitive resin occurs is the reference plane of the light-curing 3D printing device 1. The detection device 2 takes this reference plane as the standard to detect the flatness of the forming surface 1.5 of the forming platform 1.1.

[0043] Such as Figure 3 and Figure 4As shown, the detection device 2 includes a control system 2.5 and one or more detection units 2.1. Each detection unit 2.1 includes a transmission member and one or more contact sensors 2.14. The transmission member is connected to a power source 2.2, which is generally a motor. The control system 2.5 controls the opening and closing of the power source 2.2. Since three points determine a plane, the detection device 2 as a whole includes at least three contact sensors 2.14, and the contacts 2.141 of all the contact sensors 2.14 are located on a plane parallel to the reference plane. The contacts 2.141 of the contact sensors 2.14 have a displaceable travel distance in the direction perpendicular to the reference plane. During detection, the forming surface 1.11 of the forming table 1.1 will successively abut against the contacts 2.141, and the contacts 2.141 will undergo a certain displacement in the direction perpendicular to the reference plane. The control system 2.5 can read the displacement travel distance of the contacts 2.141, and the maximum travel distance of the contacts 2.141 is the error value of the flatness of the forming surface 1.11 of the forming table. The control system 2.5 compares this error value with the pre-set flatness threshold of the forming surface 1.11 of the forming table and determines whether the flatness of the forming table is qualified according to the pre-set standard. For example, the detection device 2 can be pre-set such that when the measured error value is less than the flatness threshold of the forming surface of the forming table, the flatness of the forming surface of the forming table is qualified; conversely, when the measured error value is equal to or greater than the flatness threshold of the forming surface of the forming table, the flatness of the forming surface of the forming table is unqualified.

[0044] In some embodiments, the detection device 2 includes a control system 2.5 and three or more detection units 2.1. Each detection unit 2.1 includes a transmission member and one contact sensor 2.14, and the contact sensor 2.14 is connected to the transmission member. Each contact sensor is independently controlled by the connected transmission member, so that when each contact sensor is measuring, after translating into the spatial region covered by the displacement of the forming table in the direction perpendicular to the reference plane on a plane parallel to the reference plane, its specific position can be adjusted separately.

[0045] In some embodiments, the detection device 2 includes a control system 2.5 and multiple detection units 2.1. Some of the detection units 2.1 include a transmission member and one contact sensor 2.14, and the transmission members of some of the detection units 2.1 are connected to multiple contact sensors 2.14, and the contact sensors 2.14 are connected to the transmission members. Each contact sensor is controlled by the connected transmission member, so that when each contact sensor is measuring, after translating into the spatial region covered by the displacement of the forming table in the direction perpendicular to the reference plane on a plane parallel to the reference plane, its specific position can be adjusted separately.

[0046] In some embodiments, the detection device 2 includes a control system 2.5 and more than three detection units 2.1. Some of the detection units 2.1 include a transmission member and a contact sensor 2.14, and the contact sensor 2.14 is connected to the transmission member. Some of the detection units 2.1 have a transmission member but do not include a contact sensor 2.14.

[0047] In some embodiments, the detection device 2 includes a control system 2.5 and a plurality of detection units 2.1. Some of the detection units 2.1 include a transmission member and one or more contact sensors 2.14, and the contact sensor 2.14 is connected to the transmission member. Some of the detection units 2.1 have a transmission member but do not include a contact sensor 2.14.

[0048] In some embodiments, all the transmission members can be interconnected with each other through a linkage member 2.4 to form a transmission system. Specifically, the linkage member 2.4 can be a transmission component such as a belt or a connecting rod. The linkage member 2.4 is simultaneously connected to the power source 2.2. The power source 2.2 is interlocked with all the transmission members through the linkage member 2.4, and the movement speeds and directions of all the transmission members are the same. In these embodiments, each contact sensor 2.14 is controlled by the interlocked transmission members, so that when each contact sensor measures, it translates into the space area covered by the displacement of the molding table 1.1 in the direction perpendicular to the reference plane at the same movement speed and direction in a plane parallel to the reference plane. Further, in some embodiments, after all the contact sensors 2.14 translate into the space area covered by the displacement of the molding table 1.1, the specific positions of each contact sensor 2.14 can be further controlled by the linkage member.

[0049] In some embodiments, some of the transmission members can be interconnected with each other through a linkage member 2.4 to form a transmission system. Specifically, the linkage member 2.4 can be a transmission component such as a belt or a connecting rod. The linkage member 2.4 is simultaneously connected to the power source 2.2. The power source 2.2 is interlocked with the transmission members through the linkage member 2.4, and the movement speeds and directions of the interlocked transmission members are the same; some of the transmission members are individually connected to the power source 2.2, and the control system 2.5 controls the power source 2.2 to achieve the regulation of the movement speed and direction of the transmission member.

[0050] In some embodiments, each transmission member is respectively connected to an independent power source 2.2, and the control system 2.5 controls the power source 2.2 to respectively achieve independent regulation of the movement speed and direction of the transmission member.

[0051] Specifically, the transmission member includes a shaft 2.11, a bearing and a connecting member 2.13, wherein a sleeve 2.12 is arranged on the shaft 2.11, and the shaft 2.11 of the transmission member is linked to the power source 2.2 through transmission components such as belts and connecting rods. The connecting member 2.13 is respectively connected to the shaft 2.11 and the contact sensor 2.14, and the connecting member 2.13 is used to extend the distance between the contact sensor 2.14 and the shaft 2.11. Preferably, the surface of the sleeve 2.12 is provided with a texture for increasing friction, the belt is in contact with the sleeve 2.12, and the sleeve 2.12 drives the shaft 2.11 for transmission.

[0052] In some embodiments, a contact sensor 2.14 is fixed on the connecting piece 2.13 of each detection unit 2.1 in the detection device 2.

[0053] Specifically, the connecting member 2.13 is a long straight plate, one end of the connecting member 2.13 is fixed to the contact sensor 2.14, and the other end of the connecting member 2.13 is passed through and fixed on the shaft 2.11 and linked to the shaft 2.11. When the shaft 2.11 rotates, the connecting member 2.13 drives the contact sensor 2.14 to rotate around the shaft 2.11 as the axis.

[0054] In some embodiments, a plurality of contact sensors 2.14 are fixed on the connecting piece 2.13 of each detection unit 2.1 in the detection device 2.

[0055] Specifically, the connecting member 2.13 is a hard flat plate with high surface flatness accuracy. A plurality of contact sensors 2.14 are distributed on the surface of the connecting member 2.13. The contact sensor 2.14 is detachably connected to the connecting member 2.13. The position of the contact sensor 2.14 on the connecting member 2.13 can be adjusted according to detection requirements. The connecting member 2.13 is fixed on the shaft 2.11 and is linked to the shaft 2.11. When the shaft 2.11 rotates, the connecting member 2.13 drives the contact sensor 2.14 to rotate with the shaft 2.11 as the axis.

[0056] Alternatively, the connecting member 2.13 is a long straight plate, on which a plurality of contact sensors 2.14 are arranged in sequence. The contact sensor 2.14 is detachably connected to the connecting member 2.13, and the position of the contact sensor 2.14 on the connecting member 2.13 can be adjusted according to detection requirements. The other end of the connecting member 2.13 is passed through and fixed on the shaft 2.11 and is linked to the shaft 2.11. When the shaft 2.11 rotates, the connecting member 2.13 drives the contact sensor 2.14 to rotate with the shaft 2.11 as the axis.

[0057] Alternatively, each detection unit 2.1 in the detection device 2 has a plurality of connecting members 2.13. The connecting members 2.13 are respectively connected to the shaft 2.11 and interlocked with the shaft 2.11. Independent movement can be achieved between the plurality of connecting members 2.13. One or more contact sensors 2.14 are fixed on each connecting member. By controlling each connecting member 2.13, the specific position of the contact sensor 2.14 on the connecting member 2,13 can be adjusted.

[0058] In addition, in order to ensure that the surfaces of the contacts 2.141 of the contact sensors 2.14 of all the detection units 2.1 are on the same plane, the components forming the detection unit 2.1 should use unified dimensions. In order to ensure the stability of the detection unit 2.1 during use, the transmission member can be fixed on the magnetic base 2.3, and the magnetic base 2.3 is directly in contact with the stereolithography 3D printing device 1. All the used magnetic bases 2.3 are of the same size.

[0059] Since the detection device 2 described in the present invention is composed of various components, the dimensions of each component itself, the installation position of the detection device 2, and the program settings of the control system 2.5 can all be adjusted according to specific detection requirements. Specifically, the movement speed and direction of the transmission member 2.11, the length of the connecting member 2.13, and the installation position of each detection unit 2.1 on the stereolithography 3D printing device 1 jointly determine the movement trajectory and translation distance of the contact sensor 2.14 during translation. Further, whether all or some of the transmission members are interlocked can also determine the movement trajectory and translation distance of the contact sensor 2.14 during translation. In some embodiments, the detection unit 2.1 has a plurality of connecting members 2.13. Independent movement can be achieved between the plurality of connecting members 2.13. One or more contact sensors 2.14 are fixed on each connecting member. By controlling each connecting member 2.13, independent control of the specific position of the contact sensor 2.14 on the connecting member 2,13 can be achieved.

[0060] In some embodiments (taking Figure 3 as an example), the frame of the stereolithography 3D printing device 1 has an operation table 1.4 for placing the material box 1.2. The bottom of the material box is the occurrence plane of stereolithography. The detection device 2 described in the present invention is installed on the operation table 1.4. A plurality of detection units 2.1 are respectively placed around the material box 1.2. Preferably, after the detection unit 2.1 is fixed on the operation table 1.4, the plane where the plurality of contact sensors 2.14 are located should be higher than the highest point of the material box 1.2, so that the plurality of contact sensors 2.14 are not blocked during translation in a plane parallel to the stereolithography occurrence plane 1.5. Preferably, the installation positions of the plurality of detection units 2.1 are as scattered as possible, so that the detection range of the contact sensor 2.14 is wider.

[0061] The adjustable variables of the above detection device 2 should be adjusted according to specific detection requirements, and the adjustment should follow the following principles:

[0062] First, during detection, the contact sensors should be dispersed at different positions on the forming surface of the forming table as much as possible; second, during detection, the specific positions where the contact sensors contact the forming surface of the forming table can be random; third, the installation of the detection device should not affect the printing process of the detected stereolithography 3D printing device as much as possible; fourth, when the area of the forming surface of the device's forming table is large, more contact sensors can be adopted to ensure that the detection covers all areas of the forming surface of the forming table; fifth, in order to ensure the accuracy of the measurement results, multiple measurements can be taken, and the contact sensors for each measurement can be placed at different positions.

[0063] In some embodiments, such as Figure 6 During the detection shown, after the contact sensors 2.14 are translated into the spatial area covered by the displacement of the forming table 1.1, the connection lines of all the contact sensors 2.14 form a regular polygon. For example, the connection lines of three contact sensors 2.14 form an equilateral triangle; the connection lines of four contact sensors 2.14 form a square.

[0064] In some embodiments, such as Figure 7 During the detection shown, when the contact sensors 2.14 are translated into the spatial area covered by the displacement of the forming table 1.1, at least one contact sensor 2.14 is located in the central part of the spatial area, and the remaining contact sensors 2.14 are randomly distributed.

[0065] A forming table detection device 2 for a stereolithography 3D printing device 1 according to the present invention, with the stereolithography occurrence plane 1.5 as the reference plane, and the method for detecting the flatness of the forming surface 1.11 of the forming table based on the reference plane includes:

[0066] Step a, after the stereolithography 3D printing device 1 is installed, the detection device 2 is installed on the stereolithography 3D printing device 1. The contact surface 2.141 of the contact sensors 2.14 is located on a plane parallel to the 3D printing reference plane, and the flatness threshold of the forming surface 1.11 of the forming table is input into the control system 2.5 of the detection device 2.

[0067] Step b, start the detection device 2 of the stereolithography 3D printing device 1. The control system 2.5 controls the power source 2.2 to start all transmission parts, so that all contact sensors 2.14 are translated into the spatial area covered by the displacement of the forming table 1.1 in the direction perpendicular to the reference plane on a plane parallel to the reference plane, and the positions of each contact sensor 2.14 are adjusted.

[0068] Step c: The forming table 1.1 starts to displace in a direction perpendicular to the reference plane towards the proximity sensor 2.14. During the displacement process, the proximity sensors 2.14 contact the forming surface 1.11 of the forming table in a certain order. When all the proximity sensors 2.14 are in contact with the forming surface 1.11 of the forming table, each proximity sensor 2.14 feeds back the displacement travel distance of its contact 2.141 in the direction perpendicular to the reference plane to the control system 2.5.

[0069] Step d: The control system 2.5 compares the magnitudes of the displacement travel distances of the contacts 2.141. The maximum value of the travel distance is the flatness error value of the forming surface 1.11 of the forming table. This error value is compared with the flatness threshold of the forming surface 1.11 of the forming table, and it is determined whether the flatness of the forming table is qualified according to the preset standard.

[0070] As Figure 5 shown, after the detection is completed, the control system 2.5 activates the power source 2.2, and the power source 2.2 activates all transmission parts, causing all the proximity sensors 2.14 to translate out of the spatial area covered by the displacement of the forming table 1.1. Preferably, the control system 2.5 can be interconnected with the industrial control computer of the stereolithography 3D printing device 1. When the detection result is qualified, the control system 2.5 feeds back the result to the industrial control computer. After all the proximity sensors 2.14 translate out of the spatial area covered by the displacement of the forming table 1.1, the stereolithography 3D printing device 1 can directly perform subsequent printing operations. In addition, the detection device 2 is connected to an alarm, and the alarm is connected to the control system 2.5. When the detection result is unqualified, the control system 2.5 outputs an instruction, and the alarm gives an alarm.

[0071] Among them, the flatness threshold of the forming surface 1.11 of the forming table in step a is adjustable according to the size of the area of the forming surface 1.11 of the forming table. Theoretically, the smaller the flatness error value of the forming surface 1.11 of the forming table, the better. The forming table 1.1 with a larger surface area of the forming surface is suitable for large-format stereolithography printing. The flatness requirement for the forming surface 1.11 of large-format stereolithography printing is not lower than that of small-format stereolithography printing. However, considering the existing processing technology of the forming table 1.1, since the larger the area of the forming surface 1.11 of the forming table, the greater the processing difficulty. Therefore, in actual operation, the acceptable flatness error value of the forming table 1.1 with a larger surface area may be greater than the flatness error value of the forming table 1.1 with a smaller surface area. For example, for a forming table 1.1 with a surface area size of 100mm * 160mm, the flatness error value is required not to exceed 0.02mm; for a forming table 1.1 with a surface area size of 330mm * 350mm, the flatness error value is required not to exceed 0.05mm.

[0072] Among them, according to the detection result of controlling the system 2.5 in step d, if the detection result is qualified, steps b, c, and d can be repeated for at least one recheck. For each detection, at least one position of the position where all the contact sensors 2.14 are translated into the space area covered by the displacement of the forming table 1.1 in step b is different from the position of the contact sensor 2.14 in the previous step b.

[0073] Detection example

[0074] Detect the forming table 1.1 with a forming surface area of 100mm * 160mm. For the requirements of stereolithography 3D printing, the flatness error of the forming table 1.1 should not exceed 0.02mm. Such as Figure 3As shown, the detection device 2 includes four detection units 2.1 and a control system 2.5. Among them, three detection units 2.1 each have a contact sensor 2.14 and a transmission member, and the other detection unit 2.1 only has a transmission member. The detection unit 2.1 with only the transmission member is connected to the motor. The transmission members of the four detection units 2.1 are connected by a belt 2.4. The control system 2.5 controls the opening and closing of the motor so that all the transmission members are linked with the motor. Before detection, the four detection units 2.1 are respectively installed around the material box 1.2. The translatable part in the detection unit 2.1 should be higher than the highest point of the material box 1.2. Generally, the height of the material box 1.2 is 10 - 20 cm. The plane where the three contact sensors 2.14 are located is parallel to the light curing occurrence plane 1.5. During detection, under the control of the control system 2.5, the three contact sensors 2.14 translate into the space area covered by the displacement of the forming table 1.1 in the direction perpendicular to the light curing occurrence plane 1.5. When the lower surface of the forming table 1.1, that is, the forming surface 1.11 of the forming table, descends to the plane where the contact sensors 2.14 are located, the three contact sensors 2.14 contact the forming surface 1.11 of the forming table in a certain order. When all three contact sensors 2.14 are in contact with the forming surface 1.11 of the forming table, each contact sensor 2.14 feeds back the displacement travel distance of its contact 2.141 in the direction perpendicular to the light curing occurrence plane 1.5 to the control system 2.5. The control system 2.5 compares the magnitudes of the three received displacement travel distances to obtain the maximum value, which is the error value of the flatness of the forming surface 1.11 of the forming table measured for the first time. This error value is 0.012 mm. Subsequently, a second detection is carried out. First, the forming table 1.1 is raised again to return to its initial position, and then the control system 2.5 turns on the motor to start all the linkage members, driving the three contact sensors 2.14 to translate so that the positions of their contacts 2.141 are different from those in the first detection, and then the detection steps are carried out again. The detection result of the second time is that the error value of the flatness of the forming surface 1.11 of the forming table is 0.008 mm. Since the error values of the two detections are both lower than the threshold value of 0.02 mm for the surface flatness of the forming table to be measured, it is considered that the forming table 1.1 is qualified and the detection is completed. After the detection is completed, the control system 2.5 turns on the motor to start all the linkage members, driving the three contact sensors 2.14 to translate so that all the contacts 2.141 translate out of the space area covered by the displacement of the forming table 1.1 in the direction perpendicular to the light curing occurrence plane 1.5, thus ending the detection of the forming table 1.1.

[0075] As described above, it is only a preferred and feasible implementation example of the present invention, and thus cannot limit the scope of the rights of the present invention. For those skilled in the art, all other corresponding changes made by using the technical solutions and technical concepts of the present invention should fall within the protection scope of the claims of the present invention.

Claims

1. A forming table detection device for a light-curing 3D printing device. The light-curing occurrence plane of the light-curing 3D printing device is the reference plane of this detection device. This detection device detects the flatness of the forming surface of the forming table based on the reference plane. It is characterized in that the detection device includes a control system and one or more detection units. The detection unit includes a transmission member and at least three contact sensors. The transmission member is connected to a power source, and the control system controls the opening and closing of the power source. The contacts of the contact sensors are all located on a plane parallel to the reference plane, and the contacts of the contact sensors have a displaceable travel distance in the direction perpendicular to the reference plane. The control system can read the travel distance of the contacts. When the detection device is detecting, the control system controls the power source to start the transmission member, so that all the contact sensors are translated on the plane parallel to the reference plane into the space area covered by the displacement of the forming table in the direction perpendicular to the reference plane. When the detection device finishes detecting, the power source starts the transmission member, so that all the contact sensors are translated on the plane parallel to the reference plane out of the space area covered by the displacement of the forming table in the direction perpendicular to the reference plane. A threshold value of the flatness of the forming surface of the forming table is input into the control system. When the detection device is detecting, the forming table moves in the direction perpendicular to the reference plane towards the direction close to the contact sensors. During the displacement process, the contact sensors contact the forming surface of the forming table in a certain order. When all the contact sensors are in contact with the forming surface of the forming table, each contact sensor feeds back the displacement travel distance of its contact in the direction perpendicular to the reference plane to the control system. The maximum value in this travel distance is the error value of the flatness of the forming surface of the forming table. This error value is compared with the flatness threshold value of the forming surface of the forming table, and it is determined whether the flatness of the forming table is qualified according to the preset standard.

2. The forming table detection device for a light-curing 3D printing device according to claim 1, characterized in that, The detection device is connected with an alarm. The alarm is connected to the control system. If the detection result of the forming table detection device is unqualified, the control system outputs an instruction and the alarm gives an alarm.

3. The forming table detection device for a light-curing 3D printing device according to claim 1, characterized in that, After all the contact sensors are translated into the space area covered by the displacement of the forming table, the connections of all the contact sensors form a regular polygon.

4. The forming table detection device for a light-curing 3D printing device according to claim 1, characterized in that, After all the contact sensors are translated into the space area covered by the displacement of the forming table, at least one contact sensor is located in the central part of this space area.

5. The forming table detection device for a light-curing 3D printing device according to claim 1, wherein, The power source is a motor, and the transmission members are interlinked with each other and connected to the motor.

6. The forming table detection device for a light-curing 3D printing device according to claim 1 or 5, characterized in that, The transmission member includes a shaft, a bearing and a connecting member. The connecting member is respectively connected to the shaft and the contact sensor.

7. The forming table detection device for a light-curing 3D printing device according to claim 6, characterized in that, The transmission members are interlinked through a belt or a connecting rod, or the shafts are interlinked through a belt or a connecting rod.

8. The forming table detection device for a light-curing 3D printing device according to claim 6, characterized in that, The connecting member is strip-shaped. One end of the connecting member is provided with a contact sensor, and the other end of this connecting member is inserted on the shaft and interlinked with the shaft.

9. The forming table detection device for a light-curing 3D printing device according to claim 6, characterized in that, The length of the connecting member is adjustable according to the surface area size of the measured forming table.

10. The forming table detection device for a light-curing 3D printing device according to claim 1, characterized in that, When the detection device is detecting, the position reached by the translation of the contact sensor on the plane parallel to the reference plane is adjustable.

11. The forming table detection device for a light-curing 3D printing device according to claim 1, characterized in that, The detection device may further include one or more detection units each only containing transmission parts.

12. The forming table detection device for a light-curing 3D printing device according to claim 1 or 11, characterized in that, The transmission parts are connected to a magnetic base, and the magnetic base is in direct contact with the stereolithography 3D printing device.

13. A detection method for a forming platform detection device of a stereolithography 3D printing device, the method using the detection device according to any one of claims 1-12, taking the stereolithography occurrence plane as the reference plane, and detecting the flatness of the forming surface of the forming platform with reference to the reference plane. The method specifically includes: Step a: After the stereolithography 3D printing device is installed, install the detection device on the stereolithography 3D printing device. The contact surfaces of the contact sensors are all located on a plane parallel to the 3D printing reference plane, and input the flatness threshold of the forming surface of the forming platform into the control system of the detection device. Step b: Start the detection device of the stereolithography 3D printing device. The control system controls the power source to start all transmission parts, so that all contact sensors are translated in a plane parallel to the reference plane into the space area covered by the displacement of the forming platform in the direction perpendicular to the reference plane, and adjust the position of each contact sensor. Step c: The forming platform starts to displace in the direction perpendicular to the reference plane towards the direction close to the contact sensors. During the displacement process, the contact sensors contact the forming surface of the forming platform in a certain order. When all contact sensors are in contact with the forming surface of the forming platform, each contact sensor feeds back the displacement stroke distance of its contact in the direction perpendicular to the reference plane to the control system. Step d: The control system compares the magnitudes of the displacement stroke distances of each contact. The maximum value of the stroke distance is the error value of the flatness of the forming surface of the forming platform. Compare this error value with the flatness threshold of the forming surface of the forming platform, and determine whether the flatness of the forming platform is qualified according to the preset standard.

14. The detection method of a forming table detection device for a light-curing 3D printing device according to claim 13, characterized in that, According to the detection result of the control system in step d, if the detection result is qualified, the control system starts the power source, and the power source starts all transmission parts, so that all contact sensors are translated out of the space area covered by the displacement of the forming platform.

15. A detection method for a forming table detection device of a light-curing 3D printing device according to claim 13, characterized in that, The detection device is connected to an alarm, and the alarm is connected to the control system. If the detection result in step d is unqualified, the control system outputs an instruction, and the alarm gives an alarm.

16. The detection method of a forming table detection device for a light-curing 3D printing device according to claim 13, characterized in that, In step a, the flatness threshold of the forming surface of the forming platform is adjustable according to the size of the forming surface area of the forming platform.

17. The detection method of a forming table detection device for a light-curing 3D printing device according to claim 13, characterized in that, Repeat step b, step c, and step d for at least one recheck. In each recheck, at least one of the positions where all contact sensors are translated into the space area covered by the displacement of the forming platform in step b is different from the positions of the contact sensors in the previous step b.

18. The detection method of a forming table detection device for a light-curing 3D printing device according to claim 13, characterized in that, When the contact sensors are translated into the space area covered by the displacement of the forming platform in step b, the connections of all contact sensors form a regular polygon.

19. The detection method of a forming table detection device for a photocuring 3D printing device according to claim 13, characterized in that, When the contact sensors are translated into the space area covered by the displacement of the forming platform in step b, at least one contact sensor is located in the central part of the space area.

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