Sunken type 3D printing liquid level control device and method

Abstract

The invention belongs to the technical field of 3D printing, and relates to a sinking type 3D printing liquid level control device and method. A forming table movement system of the control device is provided with a forming table placed in the multifunctional stock bin; a forming table movement mechanism is arranged corresponding to the forming table; the forming table movement mechanism is provided with a left cantilever and a right cantilever which are located over the forming table and arranged in a bilateral symmetry mode. The rear ends of the left cantilever and the right cantilever are fixedly connected with the Z-direction movement mechanism; the front end is positioned right above the multifunctional stock bin; the arranged liquid level detection system comprises at least one liquid level sensor which is parallel to the forming table; the multifunctional stock bin comprises an inner bin and an outer bin; according to the sinking type 3D printing scraper-free liquid level leveling device, the functions of scraper-free liquid level leveling of sinking type 3D printing, stable operation of a curing light source, timed stirring of light curing liquid and constant-temperature control are achieved, and long-term stable and rapid operation of sinking type 3D printing equipment is guaranteed.

Description

Technical Field

[0001] The present invention belongs to the technical field of 3D printing, and in particular relates to a sinking type 3D printing liquid level control device and method. Background Art

[0002] The sinking 3D printing technology is an advanced 3D printing technology, which is characterized by the curing light path being projected from top to bottom, and the forming table moving from top to bottom to achieve additive manufacturing. It is gradually becoming the product positioning of mainstream high-end 3D printing equipment due to its advantages such as not easy to fall off, fast printing speed, saving support materials, no need for release film, direct light source without attenuation, and the ability to print some special materials with poor light transmittance and poor fluidity.

[0003] The curing light of the sinking 3D printing technology is projected onto the upper surface of the photocurable liquid (such as photosensitive resin, ceramic slurry, etc.), and the curing thickness of each layer is determined by controlling the up and down movement of the forming table in the liquid tank. At the same time, since the forming table is condensed and the formed object on it moves up and down in the liquid tank, the surface of the photocurable liquid will no longer be flat, and the relative optical path length between the curing light source and the surface of the photocurable liquid has also changed. In order to restore the flat state of the liquid surface and the relative optical path length, the sinking 3D printing has a set of liquid level control system, which is also a rare device in the lifting 3D printing. The existing sinking liquid level control technology uses a rotating or translational scraper to restore the liquid surface to a flat state, and the up and down movement of the curing light source is used to adjust the relative optical path length.

[0004] However, due to the error in the movement of the scraper or the forming table, the scraper is easy to contact the formed part, causing jamming. A slight scraper jam will cause the last layer or several layers of the solidified material to be peeled off, and the entire molded part will have stratification and peeling defects. In severe cases, the scraper will be stuck and the printing will fail. In addition, since the light path length is adjusted by the movement of the curing light source, it is easy to cause the curing light source to shake, which will cause changes in the relative vertical and parallel relationship of the mechanical structure after long-term operation, thereby reducing the printing accuracy.

[0005] In sinking 3D printing, since the molding table moves from top to bottom, its liquid tank is generally higher to meet the molding requirements of higher objects. As a result, the liquid tank contains a large amount of photocurable liquid, and the liquid temperature is uneven and easily precipitated. Summary of the invention

[0006] The purpose of the present invention is to provide a sinking 3D printing liquid level control device and method, so as to solve the problems of easy-to-stick scraper, decreased precision caused by the movement of curing light source, and uneven temperature and easy sedimentation of light-curing liquid in the prior art, so as to achieve the technical effects of high printing success rate, good printing effect, stable equipment structure and less equipment maintenance.

[0007] The present invention adopts the following technical solutions to achieve the above-mentioned purpose: A sinking 3D printing liquid level control device, the sinking 3D printing liquid level control device has a forming table movement system; the forming table movement system has a forming table placed in a multi-functional silo; the forming table is a porous structure, and its material is a wear-resistant and non-deformable metal material, and its thickness is 1-5mm; a forming table movement mechanism is provided corresponding to the forming table to realize the vertical lifting of the horizontal plane of the forming table; the forming table movement mechanism has a left cantilever and a right cantilever located directly above the forming table and symmetrically arranged on the left and right sides; the rear ends of the left and right cantilevers are fixedly connected to the Z-direction movement mechanism; the front ends are located directly above the multi-functional silo; the left and right cantilevers are connected to the forming table through columns, and under the action of the Z-direction movement mechanism, the forming table can be vertically lifted; the sinking 3D printing liquid level control device is provided with a liquid level detection system; the liquid level detection system includes at least one A liquid level sensor installed parallel to the forming table; the multifunctional silo includes an inner silo and an outer silo, the inner silo is an opening or groove structure communicating with the outer silo, and at the same time, impurities generated in the inner silo due to the forming action will not enter the outer silo; a heating plate and an ultrasonic generator are installed in the outer silo; the two heating plates are symmetrically arranged on the left and right: a left heating plate and a right heating plate; the two ultrasonic generators are symmetrically arranged on the left and right, and are respectively located below the left heating plate and the right heating plate; an agitator is arranged at the bottom of the outer silo, so that it has the functions of heating, stirring and ultrasonic vibration of the outer silo; the function of the silo motion mechanism is to carry the multifunctional silo for vertical lifting; the Z-direction motion mechanism is fixed on a U-shaped base; the bottom of the U-shaped base is supported on the bottom of the multifunctional silo, and a light-curing light source is installed on the top of the U-shaped base, and the light-curing light source is located directly above the multifunctional silo and the liquid level detection system.

[0008] When one liquid level sensor is used, the sensor should be placed on a rotatable motion mechanism and rotate parallel to the horizontal plane of the forming table; when two liquid level sensors are used, at least one of them can move parallel to the horizontal plane of the forming table; when three or more liquid level sensors are used, the liquid level sensors can be installed parallel to the horizontal plane of the forming table and not in a fixed position in a straight line.

[0009] A silo moving mechanism for lifting the silo is arranged between the U-shaped base and the multifunctional silo; the silo moving mechanism comprises a vertical lifting platform and a silo moving motor.

[0010] A method for liquid level control using a sinking 3D printing liquid level control device is proposed. After each layer is cured and formed, the ultrasonic vibration of the multifunctional silo is controlled to achieve the function of leveling the liquid surface. The relative distance between the current liquid surface and a fixedly installed curing light source is calculated by averaging the liquid surface measurement data of three or more liquid level sensors. The multifunctional silo movement mechanism is controlled so that the multifunctional silo can accurately rise or fall to achieve real-time adjustment of the curing light path length.

[0011] The present invention proposes a sinking 3D printing liquid level control device and method, which realizes the functions of scraper-free liquid surface leveling, stable operation of the curing light source, timed stirring of the light-curing liquid and constant temperature control, thereby ensuring the long-term stable and rapid operation of the sinking 3D printing equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Attached Figure 1 It is a front view of the main structure of the present invention.

[0013] Attached Figure 2 It is a front view of the main structure of the present invention.

[0014] Attached Figure 3 This is a structural diagram of a multifunctional silo.

[0015] In the figure: 1. Light curing light source, 2. Upper travel switch, 3. Z-axis motion mechanism, 4. Bin motion motor, 5. Vertical lifting platform, 6. Bin connection block, 7. Multi-function silo outer bin, 8. Forming table, 9. Inner bin, 10. Right 1 liquid level sensor, 11. Right 2 liquid level sensor, 12. Right cantilever, 13. Left liquid level sensor, 14. Left cantilever, 15. Ultrasonic generator, 16. Left heating plate, 17. Right heating plate, 18. Agitator, 19. U-shaped base. DETAILED DESCRIPTION

[0016] The present invention is described in detail with reference to the accompanying drawings and specific embodiments: like Figure 1 , Figure 2 , Figure 3A sinking 3D printing liquid level control device, the sinking 3D printing liquid level control device has a forming table motion system; the forming table motion system has a forming table 8 placed in a multifunctional silo; the forming table 8 is a porous structure, and its material is a wear-resistant and non-deformable metal material, and its thickness is 1-5mm; a forming table motion mechanism is provided corresponding to the forming table 8 to realize the vertical lifting of the horizontal plane of the forming table; the forming table motion mechanism has a left cantilever 14 and a right cantilever 12 located directly above the forming table and symmetrically arranged on the left and right sides; the rear ends of the left cantilever 14 and the right cantilever 12 are connected to the Z The left cantilever 14 and the right cantilever 12 are connected to the molding table 8 through a column, and the molding table can be lifted and lowered vertically under the action of the Z-direction motion mechanism; the sinking type 3D printing liquid level control device is provided with a liquid level detection system; the liquid level detection system includes at least one liquid level sensor installed parallel to the molding table; when one liquid level sensor is used, the sensor should be placed in a rotatable motion mechanism and rotate parallel to the horizontal plane of the molding table; when two liquid level sensors are used, at least one of them can move parallel to the horizontal plane of the molding table; when two liquid level sensors are used, at least one of them can move parallel to the horizontal plane of the molding table; when When three or more liquid level sensors are used, the liquid level sensors can be installed in a fixed position parallel to the horizontal plane of the forming table and not in a straight line; the liquid level sensors described in this embodiment are three: the right 1 liquid level sensor 10 and the right 2 liquid level sensor fixed on the right cantilever, and the left liquid level sensor 13 fixed on the left cantilever; the multifunctional silo includes an inner silo 9 and an outer silo 7, the inner silo 9 is an opening or a groove structure connected to the outer silo, and the impurities generated in the inner silo due to the forming action will not enter the outer silo; a heating plate and an ultrasonic generator 15 are installed in the outer silo 7; the heating plates are two symmetrically arranged on the left and right: the left Heating plate 16, right heating plate 17; the two ultrasonic generators 18 are symmetrically arranged on the left and right, and are respectively located below the left heating plate and the right heating plate; an agitator 18 is arranged at the bottom of the outer bin, so that it has the functions of heating, stirring and ultrasonic vibration of the outer bin; the function of the silo movement mechanism is to carry the vertical lifting of the multifunctional silo; the Z-axis movement mechanism is fixed on the U-shaped base 19; the bottom of the U-shaped base is supported on the bottom of the multifunctional silo, and a light-curing light source 1 is installed on the top of the U-shaped base, and the light-curing light source is located directly above the multifunctional silo and the liquid level detection system.

[0017] A silo moving mechanism for lifting the silo is provided between the U-shaped base 19 and the multifunctional silo; the silo moving mechanism comprises a vertical lifting platform 5 and a silo moving motor 4.

[0018] The liquid level control method and process are as follows: Step 1: After the sinking 3D printing equipment is turned on, the Z-axis motion mechanism 3 is controlled to move to the upper limit switch 2 as the starting zero point, and the agitator 18, the left heating plate 16, and the right heating plate 17 located in the multi-functional silo outer bin 7 are controlled to turn on the functions, and the light-curing liquid in the silo is started to be stirred and heated. Generally, the temperature of the light-curing liquid is controlled to be constant at 40-45°C, and the agitator runs for 2-10 minutes.

[0019] Step 2: After the stirrer 18 stops, the ultrasonic generator 15 is controlled to turn on. Generally, the ultrasonic generator 15 stops after running for 1-5 minutes.

[0020] Step 3: After the ultrasonic generator 15 stops running, turn on the right 1 liquid level sensor 10 and the right 2 liquid level sensor 11 fixedly mounted on the right cantilever 12, and the left liquid level sensor 12 fixedly mounted on the left cantilever 14, and adjust the equipment horizontal reference so that the current reading difference of the liquid level position of the photocurable liquid in the silo detected by the three liquid level sensors, namely the right 1 liquid level sensor 10, the right 2 liquid level sensor 11 and the left liquid level sensor 12, is within the effective error. Generally, the effective error can be set to ±5-50um.

[0021] Step 4: After the equipment horizontal reference is adjusted, adjust the vertical distance from the fixed light-curing light source 1 to the light-curing liquid surface, i.e., the light path length, according to the current printing setting. Control the operation of the silo motion motor 4 to drive the vertical lifting platform 5 to move upward or downward. The bottom plate of the multifunctional silo outer bin 7 is connected to the vertical lifting platform 5 through the silo connection block 6. The light-curing liquid surface position in the silo changes with the rotation of the silo motion motor 4 until the average value of the current readings of the light-curing liquid surface position in the silo detected by the three liquid level sensors is within the effective error range of the current printing setting value. Generally, the effective error can be set to ±2-10um. After adjusting the light path length, start printing.

[0022] Step 5: When the forming table 8 moves to the position of the corresponding layer according to the setting, turn on the ultrasonic generator 15. Generally, it stops after running for 2-10s. According to the operation of adjusting the light path length in step 4, after adjusting the liquid level of the photocurable liquid, turn on the photocurable light source 1 to project the corresponding image or spot path. After reaching the set curing time, turn off the photocurable light source 1, and the forming table 8 moves to the position of the corresponding next layer according to the setting.

[0023] Step 6: Repeat step 5 until the current printing is completed, control the Z-axis motion mechanism 3 to move to the upper limit switch 2, turn off the left heating plate 16 and the right heating plate 17, and clean up the debris in the multi-functional silo inner bin 9.

Claims

1. A sinking type 3D printing liquid level control device, characterized in that: The sinking type 3D printing liquid level control device has a forming table movement system; the forming table movement system has a forming table placed in a multifunctional silo; the forming table is a porous structure, and its material is a wear-resistant and non-deformable metal material with a thickness of 1-5mm; a forming table movement mechanism is provided corresponding to the forming table to realize the vertical lifting of the horizontal plane of the forming table; the forming table movement mechanism has a left cantilever and a right cantilever located directly above the forming table and symmetrically arranged on the left and right; the rear ends of the left and right cantilevers are fixedly connected to the Z-direction movement mechanism; the front end is located directly above the multifunctional silo; the left and right cantilevers are connected to the forming table through columns, and under the action of the Z-direction movement mechanism, the forming table can be vertically lifted and lowered; the sinking type 3D printing liquid level control device is provided with a liquid level detection system; the liquid level detection system includes at least one cantilever installed parallel to the forming table The liquid level sensor; the multifunctional silo comprises an inner silo and an outer silo, the inner silo is an opening or a groove structure communicating with the outer silo, and at the same time, impurities generated in the inner silo due to the molding action will not enter the outer silo; a heating plate and an ultrasonic generator are installed in the outer silo; the two heating plates are symmetrically arranged on the left and right: a left heating plate and a right heating plate; the two ultrasonic generators are symmetrically arranged on the left and right, and are respectively located below the left heating plate and the right heating plate; an agitator is arranged at the bottom of the outer silo, so that it has the functions of heating, stirring and ultrasonic vibration of the outer silo; the function of the silo motion mechanism is to carry the multifunctional silo for vertical lifting; the Z-direction motion mechanism is fixed on a U-shaped base; the bottom of the U-shaped base is supported on the bottom of the multifunctional silo, and a light-curing light source is installed on the top of the U-shaped base, and the light-curing light source is located directly above the multifunctional silo and the liquid level detection system.

2. A sinking type 3D printing liquid level control device as claimed in claim 1, characterized in that: When one liquid level sensor is used, the sensor should be placed on a rotatable motion mechanism and rotate parallel to the horizontal plane of the forming table; when two liquid level sensors are used, at least one of them can move parallel to the horizontal plane of the forming table; when three or more liquid level sensors are used, the liquid level sensors can be installed parallel to the horizontal plane of the forming table and not in a fixed position in a straight line.

3. A sinking type 3D printing liquid level control device as claimed in claim 1, characterized in that: A silo moving mechanism for lifting the silo is arranged between the U-shaped base and the multifunctional silo; the silo moving mechanism comprises a vertical lifting platform and a silo moving motor.

4. A method for liquid level control using a sinking type 3D printing liquid level control device according to any one of claims 1 to 3, characterized in that: After each layer is cured and formed, the ultrasonic vibration of the multifunctional silo is controlled to achieve the function of leveling the liquid surface; the relative distance between the current liquid surface and the fixedly installed curing light source is calculated by the average value of the liquid surface measurement data of three or more liquid level sensors, and the multifunctional silo movement mechanism is controlled. The multifunctional silo can be accurately raised or lowered to achieve real-time adjustment of the curing light path length.

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