Semi-in-situ auxiliary detection device for 3d printing

Abstract

The invention provides a semi-in-situ auxiliary detection device for assisting 3d printing, and belongs to the field of 3d printing monitoring. The device comprises a forming cylinder, a servo electric cylinder and a pneumatic clamp, wherein the servo electric cylinder serves as a driving mechanism and is used for driving a piston to do lifting motion in the forming cylinder; a motor in the servo electric cylinder is in quick connection with the ball screw, and the pneumatic clamp is connected with the ball screw by reinforcing or loosening the motor through a pneumatic system. Wherein when semi-in-situ detection needs to be carried out, the whole forming cylinder is taken out, off-line detection (mu CT) is carried out, and the condition in the cylinder during powder printing is observed in an auxiliary mode. According to the auxiliary semi-in-situ detection device, on the premise that the cost and complexity are not remarkably increased, the quality of a workpiece can be efficiently monitored and optimized.

Description

Technical Field

[0001] The invention belongs to the technical field of additive manufacturing, and in particular relates to a 3D printing semi-in-situ auxiliary detection device. Background Art

[0002] Laser powder bed fusion (LPBF) is a type of additive manufacturing technology. In the metal additive manufacturing market, laser powder bed fusion (LPBF) occupies a significant, even almost dominant position. Laser powder bed fusion uses a high-power laser beam to irradiate a metal powder bed through a precise scanning system to locally melt the powder, and then solidify it through rapid cooling. The molten metal powder will be built layer by layer according to the computer-designed pattern to form the target part. After each build is completed, the unmelted metal powder will be removed, and then a new layer of powder will be laid to continue the molding. Due to its technical characteristics, there are inevitably randomly distributed micro-defects inside the parts, and effective means are needed to determine the internal characteristics of the parts.

[0003] Among the above technologies, the research on defects of parts needs to be further improved, while the existing in-situ monitoring methods of additive manufacturing are either of poor accuracy (such as infrared photography and acoustic emission) or too expensive (such as spectral analysis), and it is difficult to achieve three-dimensional imaging. Therefore, high-precision semi-in-situ detection (such as CT and neutron scattering imaging) can be considered. However, semi-in-situ detection needs to consider the existence of powder materials, so its design must consider the feasibility of removing powder for high-precision offline detection. After completing the offline detection, the powder can be put back into the manufacturing system to continue forming, ensuring the continuity and accuracy of the entire additive manufacturing process. This method can achieve efficient monitoring and optimization of part quality without significantly increasing cost and complexity. Summary of the invention

[0004] In order to solve the above problems existing in the prior art, the present invention provides a 3D printing semi-in-situ auxiliary detection device, which can be taken out for offline detection and then put back into the original system to continue molding.

[0005] To achieve the above-mentioned purpose, the present invention provides a 3D printing semi-in-situ detection device, comprising a forming cylinder, a servo electric cylinder, a pneumatic clamp, and a machine tool panel, wherein the servo electric cylinder is used as a driving mechanism to drive the piston to move up and down in the forming cylinder; wherein,

[0006] When the printed parts need to be inspected offline, the fixed end cover is connected to the machine panel with bolts, and the sleeve of the servo electric cylinder pushes the piston to move up and down in the forming cylinder. When offline inspection is required, the forming cylinder is lifted out for semi-in-situ inspection.

[0007] As a further preferred embodiment of the present invention, when the printed parts need to be inspected in situ, the fixed end cover and the platform are connected with Morse taper pins to ensure the accuracy of installation and disassembly.

[0008] As a further preferred embodiment of the present invention, the base plate is connected to the piston, the interior of the piston is hollow and connected to the sleeve, and an exhaust hole is opened at the top of the sleeve.

[0009] As a further preferred embodiment of the present invention, there is a threaded hole on each side of the fixed end cover, which is convenient for lifting the forming cylinder with a hook.

[0010] As a further preferred solution of the present invention, the fixed end cover is connected to four columns below, and a hollowed-out cylinder is connected below the columns.

[0011] As a further preferred embodiment of the present invention, the transmission device uses a servo electric cylinder, and the lead screw is connected to the motor using a detachable axial connection.

[0012] As a further preferred embodiment of the present invention, the servo electric cylinder has a groove on the outside. When printing is required, the pin of the pneumatic device is inserted into the groove to tightly connect the lead screw and the motor. When disassembly is required, the pin is loosened.

[0013] As a further preferred embodiment of the present invention, the pneumatic device is connected to the pneumatic system of the printer itself.

[0014] The 3D printing semi-in-situ auxiliary detection device of the present invention adopts the above-mentioned technical scheme, so that the forming cylinder of the present invention can be disassembled and assembled in the machine tool panel with high frequency and high precision, and the connection between the middle screw of the transmission system and the motor is also guaranteed with high precision through the pneumatic system, ensuring reliable accuracy during offline detection and continued molding, convenient disassembly and assembly, reduced time consumption and low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is an overall view of a 3D printed semi-in-situ auxiliary detection device of the present invention;

[0016] Figure 2 A top view of a 3D printed semi-in-situ auxiliary detection device of the present invention;

[0017] Figure 3 A cross-sectional view of an embodiment of a 3D printing semi-in-situ auxiliary detection device provided by the present invention;

[0018] Figure 4 This is a partial cross-sectional enlarged view of a 3D printed semi-in-situ auxiliary detection device of the present invention;

[0019] Figure 5 Another side cross-sectional view of an embodiment of a 3D printing semi-in-situ auxiliary detection device provided by the present invention;

[0020] The parts in the figure are marked as follows:

[0021] 1. Machine tool panel, 2. Morse taper pin, 3. Forming base plate, 4. Fixed end cover, 5. Piston, 6. Sleeve, 7. Angular contact ball bearing, 8. Ball screw, 9. Nut, 10. Fixed guide rail, 11. Servo electric cylinder sleeve, 12. Pneumatic latch, 13. Motor (simplified), 14. Threaded hole. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to better understand and implement the technical solution of the present invention, further detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0023] like Figure 1 The 3D printing semi-in-situ auxiliary detection device shown includes a fixed end cover 4, a piston 5, a servo electric cylinder and a pneumatic clamp 12. The pneumatic clamp 12 fixes the connection between the motor 13 in the electric cylinder and the screw 8. The servo electric cylinder is used as a driving mechanism to drive the piston 5 to move up and down in the forming cylinder. When semi-in-situ detection is required, the entire forming cylinder is taken out for semi-in-situ detection to assist in observing the condition in the cylinder during powder printing.

[0024] When the printed parts need to be tested offline, the fixed end cover 4 is connected to the machine panel 1 with a Morse taper pin 2 to ensure the accuracy of installation and disassembly.

[0025] The molding substrate 3 is connected to the piston 5. Preferably, in order to reduce the weight and manufacturing cost of the piston, the piston 5 is hollow inside and connected to the sleeve 6. The sleeve 6 has an exhaust hole at the top to prevent excessive pressure in the cylinder.

[0026] There is a threaded hole 14 on each side of the fixed end cover 4, which is convenient for lifting the device with a hook.

[0027] The driving device uses a servo electric cylinder, and the lead screw 8 is connected to the motor 13 using a detachable axial connection, which is convenient for disassembly and assembly and realizes the function of transmitting torque. The lead screw 8 rotates with the nut 9, and the nut 9 carries the sleeve 6 to move up and down along the fixed guide rail 10. The sleeve 6 and the lead screw 8 are fixed to the servo electric cylinder sleeve 11 through the angular contact ball bearing 7.

[0028] The servo electric cylinder sleeve 11 has a groove on the outside. When printing is required, the pneumatic latch 12 is inserted into the groove to tightly connect the lead screw 8 and the motor 13. When disassembly is required, the pneumatic latch 12 is loosened.

[0029] In order to enable those skilled in the art to better understand and implement the technical solution of the present invention, the technical solution of the present invention is described in detail below in combination with the accompanying drawings and in the form of embodiments:

[0030] like Figure 2 , 3 As shown, a set of forming cylinder assembly consists of a piston 3 and a fixed end cover 4, wherein the fixed end cover 4 includes a Morse taper pin 3 and a threaded hole 14, and the entire forming cylinder and the machine tool panel 1 form a sealed space.

[0031] like Figure 2 As shown, the driving mechanism is a servo electric cylinder, which includes a sleeve 6, an angular contact ball bearing 7, a ball screw 8, a nut 9, a fixed guide rail 10, a servo electric cylinder sleeve 11 and a motor 13. A detachable axial connection structure is used between the ball screw 8 and the motor 13. The motor 13 transmits torque to the ball screw 8. The ball screw 8 causes the nut 9 to slide up and down on the fixed guide rail 10. The nut 9 drives the sleeve 6 to move up and down, so that the sleeve 6 provides the piston 5 with the force to move up and down. The pneumatic joint 12 of this device utilizes the existing protective gas system of the 3D printer itself, and the pneumatic plug 12 is externally connected to the original system. The conical surface design of the pneumatic plug 12 makes the connection between the ball screw 8 and the motor 13 tighter, ensuring the transmission accuracy after the device is taken out for in-situ testing and then connected back.

[0032] The above embodiments are only preferred implementations of the present invention. The protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention should belong to the protection scope of the present invention. It should be pointed out that some modifications and modifications without departing from the principle of the present invention should be regarded as the protection scope of the present invention.

Claims

1. A 3D printing semi-in-situ auxiliary detection device, characterized in that: The 3D printing semi-in-situ auxiliary detection device comprises a machine tool panel (1), a Morse taper pin (2), a forming base plate (3), a fixed end cover (4), a piston (5), a sleeve (6), an angular contact ball bearing (7), a ball screw (8), a nut (9), a fixed guide rail (10), a servo electric cylinder sleeve (11), a pneumatic latch (12), a motor (13), and a threaded hole (14); The machine tool panel (1) is connected to a fixed end cover (4) via a Morse taper pin (2); a molding base plate (3) is installed above the piston (5), and the piston (5) can slide up and down on the inner wall of the fixed end cover (4); The bottom of the piston (5) is connected to the sleeve (6), the bottom of the sleeve (6) is connected to the nut (9), the ball screw (8) is connected to the servo electric cylinder sleeve (11) through the angular contact ball bearing (7), and the ball screw (8) rotates to drive the nut (9) to slide up and down on the fixed guide rail (10), so that the sleeve (6) drives the piston (5) to slide up and down; The connection between the ball screw (8) and the motor (13) can be disassembled. When installing, the pneumatic latch (12) is inserted into the groove of the servo electric cylinder sleeve (11), and the motor (13) rotates to drive the ball screw (8) to rotate. When disassembling, the pneumatic latch (12) is loosened. When semi-in-situ detection is required, the entire molding cylinder is taken out and offline detection (μCT) is performed to assist in observing the condition inside the cylinder during powder printing.

2. The 3D printing semi-in-situ auxiliary detection device according to claim 1, characterized in that: When the printed parts need to be inspected semi-in-situ, the fixed end cover (4) and the machine panel (1) are connected by a Morse taper pin (2) to ensure the accuracy of installation and disassembly.

3. The 3D printing semi-in-situ auxiliary detection device according to claim 1, characterized in that: The base plate (4) is connected to the piston (5), the interior of the piston (5) is hollow and connected to the sleeve (6), and the sleeve (6) is provided with an exhaust hole at the top.

4. The 3D printing semi-in-situ auxiliary detection device according to claim 1, characterized in that: There is a threaded hole (14) on each side of the fixed end cover (4), which is convenient for lifting the device with a hook.

5. The 3D printing semi-in-situ auxiliary detection device according to claim 1, characterized in that: The fixed end cover (4) is connected to four upright posts, and a hollowed-out cylinder is connected to the upright posts to facilitate placement for offline detection.

6. The 3D printing semi-in-situ auxiliary detection device according to claim 1, characterized in that: The transmission device uses a servo electric cylinder, and the ball screw (8) and the motor (13) are connected using a detachable axial connection.

7. The 3D printing semi-in-situ auxiliary detection device according to claim 1, characterized in that: The servo electric cylinder sleeve (11) has a groove on the outside. When it is necessary to continue printing, the pneumatic latch (12) is inserted into the groove to tightly connect the ball screw (8) and the motor (13). When offline testing is required, the pneumatic latch (12) is released.

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