Double-spring laminate buffering type weightlessness simulation 3D printing equipment and method

Abstract

The invention belongs to the technical field of additive manufacturing equipment, and particularly discloses double-spring laminate buffering type weightlessness simulation 3D printing equipment and method.The double-spring laminate buffering type weightlessness simulation 3D printing equipment comprises a sliding rail base, double sliding rails, a single sliding rail, a base plate base, a laser powder feeding system, a motor and a double-spring laminate, and the double sliding rails and the single sliding rail are vertically fixed to the sliding rail base; the two sides of the base plate base are installed on two sliding rails of the double sliding rails through sliding blocks respectively, and a forming base plate is fixed to the base plate base. The laser powder feeding system is installed on the single sliding rail through a sliding block. The motor is used for driving the slider to move; the double-spring layer plate is installed on the sliding rail base, and the double sliding rails penetrate through the double-spring layer plate. The double-spring layer plate comprises an upper spring layer, a clamping plate and a lower spring layer which are sequentially and fixedly connected from top to bottom. The weightlessness 3D printing is realized through the forming platform and the free falling body of laser, and the weightlessness 3D printing process can be continuously and stably simulated by returning to the initial position through the motor after buffering and rebounding of the double-layer spring plate.

Description

Technical Field

[0001] The present invention belongs to the technical field of additive manufacturing equipment, and more specifically, relates to a double-spring layer buffer type simulated weightlessness 3D printing equipment and method. Background Art

[0002] Space manufacturing technology is currently a key research area, among which additive manufacturing (3D printing) technology has outstanding advantages such as fast speed, integrated formation, the ability to obtain complex structural parts, convenient operation, and easy replenishment of raw materials. At the same time, the oxygen-free nature of space also overcomes the need to reduce oxygen before printing in additive manufacturing technology. Therefore, the use of additive manufacturing technology to process parts in space is very promising. In order to conduct faster and deeper research on space additive manufacturing, it is necessary to first simulate the special environment in space on Earth, such as weightlessness, large temperature differences, and strong radiation.

[0003] When simulating various special environments in space on Earth, the most difficult one to achieve is the weightless environment. Currently, the recognized methods for studying weightlessness include: counterweighting in water, parabolic flight of aircraft, etc. However, it is difficult to combine the above methods with 3D printing technology, and the implementation cost is high. Therefore, there is an urgent need for a 3D printing device that can simulate a weightless environment to promote the research and development of space additive manufacturing. Summary of the invention

[0004] In view of the above defects or improvement needs of the prior art, the present invention provides a double-spring layer buffer type simulated weightlessness 3D printing device and method, the purpose of which is to continuously and stably simulate the weightlessness 3D printing process.

[0005] To achieve the above object, according to one aspect of the present invention, a double spring layer plate buffer type simulated weightlessness 3D printing device is proposed, comprising a slide rail base, a double slide rail, a single slide rail, a substrate base, a laser powder feeding system, a motor and a double spring layer plate, wherein:

[0006] The double slide rail and the single slide rail are both vertically fixed on the slide rail base; the two sides of the substrate base are respectively installed on the two slide rails of the double slide rail through sliders, and a forming substrate is fixed on the substrate base; the laser powder feeding system is installed on the single slide rail through the slider; the motor is used to drive the slider to move;

[0007] The double spring layer plate is installed on the slide rail base, and the double slide rail passes through the double spring layer plate; the double spring layer plate comprises an upper spring layer, a clamping plate and a lower spring layer which are fixedly connected in sequence from top to bottom.

[0008] As a further preference, the ratio of the total elastic coefficient of the springs in the upper spring layer to the total elastic coefficient of the springs in the lower spring layer is 1 / 3 to 1 / 2.

[0009] As a further preferred embodiment, the upper spring layer includes two spring groups, each spring group corresponds to one of the double slide rails, each spring group includes three springs, and the three springs are arranged in a triangle with the corresponding slide rail as the center; the lower spring layer includes four springs, and the four springs are arranged in a parallelogram.

[0010] As a further preference, a mounting plate is fixed to the upper end of the upper spring layer, and a lower elastic buffer pad is arranged on the mounting plate.

[0011] As a further preferred embodiment, vertical reinforcement plates are fixed around the slide rail base, and the reinforcement plates are used to prevent the clamping plate and the mounting plate from moving in a non-vertical direction.

[0012] As a further preference, the substrate base comprises an upper base and a lower base, the upper base and the lower base are fixedly connected by an X-shaped cross fixing rod; the forming substrate is fixed on the upper base, and the lower side of the lower base is covered with an upper elastic buffer pad.

[0013] As a further preference, it also includes a control platform, which controls the movement of the slider through a motor; there are three motors in total, which are respectively fixed on the top ends of the two slide rails of the single slide rail and the double slide rail.

[0014] As a further preference, the upper ends of the double slide rail and the single slide rail are both provided with limit checkpoints, and elastic gaskets are fixed to the lower sides of the limit checkpoints.

[0015] As a further preference, the lengths of the double slide rail and the single slide rail are both 2000 mm to 4500 mm.

[0016] According to another aspect of the present invention, a double spring layer buffer type simulated weightlessness 3D printing method is provided, which is implemented using the above-mentioned device and includes the following steps:

[0017] S1. Initially, the motor controls the slider so that the substrate base is located on the top of the double slide rails, and the laser powder feeding system is located above the forming substrate;

[0018] S2, the substrate base and the laser powder feeding system are free falling, and the forming substrate and the laser powder feeding system remain relatively still during the free falling process, so that the laser powder feeding system prints on the forming substrate;

[0019] S3, the substrate base falls down and contacts the double spring layer plate, and the double spring layer plate buffers and rebounds the substrate base. When the substrate base is about to lose kinetic energy, the motor controls the slider to return the substrate base and the laser powder feeding system to the initial position;

[0020] S4. Repeat steps S2 and S3 until the entire printing process is completed.

[0021] In general, the above technical solution conceived by the present invention has the following technical advantages compared with the prior art:

[0022] 1. The present invention can realize the synchronous free fall of the laser powder feeding system and the forming substrate through the design of two sets of slide rails and sliders, thereby simulating the weightless 3D printing process; at the same time, a double-layer spring plate is designed. When the double-layer spring plate is impacted from above, the upper spring layer contracts first to absorb energy and buffer, and then the lower spring layer contracts to absorb energy. After the spring contracts to the limit, the substrate base is ejected vertically upward. Through their cooperation, the forming substrate is stably decelerated and the energy consumption of the motor returning to the initial position is reduced, so that a continuous and stable simulation of the weightless 3D printing process can be achieved.

[0023] 2. The double-layer spring plate of the present invention can realize the step-by-step conversion of gravitational potential energy into kinetic energy, avoiding excessive instantaneous impact that reduces the life of the equipment. Specifically, the elastic coefficient ratio of the upper spring and the lower spring is designed. The main function of the upper spring is to absorb impact energy and provide a longer buffer when the object falls. Selecting a relatively soft spring can allow a larger deformation amount, thereby storing more energy; and selecting a relatively hard spring for the lower spring ensures that after the upper spring is compressed to the maximum deformation, the lower spring can quickly release the stored energy and provide a stronger rebound force.

[0024] 3. The present invention designs the arrangement of the springs in the upper and lower spring layers to achieve the best force arrangement. Specifically, the triangular arrangement is a very stable geometric shape, and this stability enables the upper springs in the triangular arrangement to better withstand and disperse the impact force, thereby enhancing the buffering effect of the upper layer in the entire double-layer spring plate; the lower springs are parallelograms, and their shape changes and the reduction in the number of springs make the stress feedback more rapid and concentrated, thereby enhancing the rebound effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the structure of a double-spring layer buffer type simulated weightlessness 3D printing device according to an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of a conjoined slider and related structures according to an embodiment of the present invention;

[0027] Figure 3 This is a schematic diagram of the double spring layer structure of an embodiment of the present invention;

[0028] Figure 4 (a) and (b) are schematic diagrams of spring arrangement in the upper spring layer and the lower spring layer in an embodiment of the present invention;

[0029] Figure 5 This is a schematic diagram of the printing stroke of the weightless 3D printing device simulated in an embodiment of the present invention.

[0030] In all the drawings, the same figure numbers are used to represent the same elements or structures, among which: 1-combined slider, 2-double spring layer plate, 3-powder feeding and laser system, 4-single slider, 5-motor, 6-forming substrate, 7-substrate base, 8-upper elastic buffer pad, 9-lower elastic buffer pad, 10-slide rail, 11-slide rail base, 12-control platform, 101-upper slider, 102-lower slider, 103-limiting checkpoint, 104-elastic gasket, 105-connecting plate, 106-X-shaped cross fixing rod, 201-upper spring layer, 202-clamp, 203-lower spring layer, 204-front reinforcement plate, 205-side reinforcement plate. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0032] The embodiment of the present invention provides a double spring layer buffer type simulated weightlessness 3D printing device, such as Figure 1 As shown, it includes a slide rail base 11, a double slide rail, a single slide rail, a substrate base 7, a laser powder feeding system 3, a control platform 12, a motor 5 and a double spring layer plate 2, wherein:

[0033] The slide rail base 11 is firmly fixed to the ground. Both the double slide rail and the single slide rail are vertically fixed on the slide rail base 11. The double slide rail includes two symmetrical slide rails 10, that is, there are three vertical slide rails in total.

[0034] The double slide rails are provided with a conjoined slider 1 for controlling the movement of the formed substrate 6. The conjoined slider 1 can move linearly along the slide rail in the Z axis (for ease of expression, the vertical direction is used as the Z axis to construct a spatial rectangular coordinate system), and the two sides of the substrate base 7 are respectively installed on the two slide rails of the double slide rails through the conjoined slider 1, and the overall structure is an axisymmetric structure; the formed substrate 6 is fixed on the substrate base 7 and is firmly fixed by screws to prevent shaking when falling.

[0035] Specifically, Figure 2As shown, the conjoined slider 1 specifically includes an upper slider 101 and a lower slider 102. The upper slider 101 and the lower slider 102 are coupled to the slide rail through their own structures, locked in the XY plane and freely movable in the Z axis. At the same time, the upper slider 101 and the lower slider 102 become a rigid body through the connecting plate 105 under the fixation of M8 screws, and the two remain relatively still. A limit checkpoint 103 is set at the upper end of the slide rail, and an elastic gasket 104 is set under the limit checkpoint 103 to control the maximum travel range and the printing starting point and reduce the impact of the return stroke.

[0036] Furthermore, the substrate base 7 includes an upper base and a lower base, the upper base is fixed on the upper slider 101, and the lower base is fixed on the lower slider 102, and the upper base and the lower base are fixedly connected by an X-shaped cross fixing rod 106 to improve the stability of the overall structure; the forming substrate 6 is fixed on the upper base, and the lower side of the lower base is covered with an upper elastic buffer pad 8.

[0037] A single slider 4 is provided on the single slide rail to control the movement of the powder feeding and laser system. The single slider can move linearly along the slide rail in the Z axis. The laser powder feeding system 3 is used for the laying and forming of metal powder. It is installed on the single slide rail through the single slider 4. The horizontal height is adjusted by the single slider 4 so that the laser powder feeding system 3 is located above the forming substrate 6, and there is a certain distance between the powder feeding nozzle and the laser without affecting each other. The relative position of the laser powder feeding system 3 and the forming substrate 6 in the horizontal plane is adjustable, and the Z axis direction remains relatively still during free fall to achieve precise forming.

[0038] Specifically, the length of the slide rail is preferably 2000-4500 mm. According to the function of free fall height and time h=1 / 2gt 2 The printing time of each cycle can be roughly guaranteed to be 2 to 3 seconds; the size of the forming substrate 6 is preferably 150mm×150mm×25mm; the powder feeding nozzle of the powder feeding and laser system 3 can provide a maximum flow rate of 20L / min and the maximum power of the laser is 1500W, and 3D printing is mainly performed by metal powder melting.

[0039] The motor 5 is used to rebound and return to the starting point. The control platform 12 drives the slider to move through the motor 5. The motor 5 is a servo motor, and there are three of them fixed on the top of the three slide rails. The control platform 12 is set outside and keeps a certain distance from the printing part, which is used to control the drive of the motor, so that the slider moves straightly along the Z axis. The motor only works when the slider moves in the Z axis to increase the working life of the motor.

[0040] The double spring layer plate 2 is mounted on the slide rail base 11, and the double slide rails penetrate the double spring layer plate 2. Figure 3As shown, the double spring layer plate 2 comprises a mounting plate, an upper spring layer 201, a clamping plate 202 and a lower spring layer 203 which are fixedly connected in sequence from top to bottom. When the double spring layer plate is impacted from above, the upper spring layer 201 absorbs energy first, and then the lower spring layer 203 contracts to absorb energy, and the base plate base is vertically ejected upward after the spring contracts to the limit.

[0041] Furthermore, a lower elastic buffer pad 9 is provided on the mounting plate, and the upper elastic buffer pad 8 and the lower elastic buffer pad 9 cover the entire impact area. The lower elastic buffer pad 9 and the upper elastic buffer pad 8 are squeezed when in impact contact to form a buffer, and cooperate with each other to reduce the impact. Vertical reinforcement plates, namely two positive reinforcement plates 204 and two side reinforcement plates 205, are fixedly provided around the slide rail base 11 to prevent the double-layer spring plate from deflecting on the XY plane during the compression process.

[0042] Furthermore, the total elastic coefficient of the springs in the upper spring layer 201 is less than the total elastic coefficient of the springs in the lower spring layer 203, so as to realize the step-by-step conversion of gravitational potential energy into kinetic energy and avoid excessive instantaneous impacts that reduce the life of the equipment. Preferably, the ratio of the total elastic coefficient of the springs in the upper spring layer 201 to the total elastic coefficient of the springs in the lower spring layer 203 is 1 / 3 to 1 / 2.

[0043] Further, the springs in the upper spring layer 201 and the springs in the lower spring layer 203 are arranged in a triangular shape (projection on the XY plane); preferably, as Figure 4 As shown, the upper spring layer 201 includes two spring groups, each spring group corresponds to one of the double slide rails, and each spring group includes three springs, which are arranged in a triangle with the corresponding slide rail as the center; the lower spring layer 203 includes four springs, and the four springs are arranged in a parallelogram, that is, two connected triangles, which serve as the best force arrangement to provide the best buffering for free fall.

[0044] When the above-mentioned equipment performs simulated weightless 3D printing, weightless 3D printing is achieved through the free fall of the forming substrate and the powder feeding and laser system. The relative positions of the two in space are adjusted to accurately control the laser scanning on the metal powder. The forming substrate is rebounded by the double-layer spring plate and then returns to the initial position through the motor, and the next layer of printing is restarted and the cycle is repeated.

[0045] like Figure 5As shown, (a) to (f) are a cycle process. With the limit checkpoint at the top of the slide rail near the joint slider as the initial starting point (a), after the powder feeding and laser systems complete the powder spreading operation, the forming substrate falls freely from an initial velocity of 0, gradually accelerates under the action of gravity acceleration, and achieves a weightless state (b). At the same time, the laser emits a high-energy laser to melt the metal powder and quickly solidify it on the forming substrate. During the whole process, the laser and the forming substrate fall freely together and remain relatively still in the Z-axis direction. When the free fall contacts the upper and lower elastic buffer pads, the double-layer spring plate is compressed and begins to absorb kinetic energy and gravitational potential energy (c ), the upper spring contracts first, and the lower spring contracts further until the kinetic energy of the formed substrate is 0 and is in an instantaneous static state (d). The double-layer spring plate releases the absorbed kinetic energy and gravitational potential energy as the initial kinetic energy for the formed substrate to return, causing it to move in the opposite direction and in a straight line in the upward direction of the Z axis (e). When the kinetic energy provided by the double-layer spring plate is almost consumed, the servo motor controls the combined slider to drive the formed substrate, and controls the single slider to drive the powder feeding and laser system to continue the return stroke until the upper end of the slider contacts the limit switch again, and the entire movement stops (f); the above process is repeated to complete the entire printing.

[0046] The following is a specific implementation to illustrate the printing process. Start the control platform in advance, turn on all power supplies, and check whether all hardware and software are working properly; open the gas cylinder, and add 316 stainless steel metal spherical powder with a particle size of 53-150μm into the powder storage tank; input the stl format model generated in the 3D modeling software in advance into the control platform, perform 3D slicing according to the layer thickness of 0.2mm, set the laser power to 1200W, the scanning speed to 700mm / min, and the flow rate to 3L / min. Then start printing, including the following steps:

[0047] S1. Initialize the printing position, place the substrate base on the top of the slide rail, pre-lay the first layer of 316L powder, perform a red light pre-scan to determine the printing range, and adjust the laser height to accurately focus on the laid powder layer;

[0048] S2, the forming substrate and the laser are made to fall freely by controlling the platform, and the two are kept relatively still in the Z-axis direction during the whole process, and printing is performed during the process;

[0049] S3, when the substrate to be formed is rebounded by the double-layer spring plate and is about to lose kinetic energy, the servo motor starts to return the formed substrate to the starting position, and at the same time adjusts the position of the powder feeding and laser system;

[0050] S4, repeat steps S2 and S3, and automatically print to complete the remaining cycles until the part is formed.

[0051] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A double spring layer buffer type simulated weightlessness 3D printing device, characterized in that: It comprises a slide rail base (11), a double slide rail, a single slide rail, a substrate base (7), a laser powder feeding system (3), a motor (5) and a double spring layer plate (2), wherein: The double slide rail and the single slide rail are both vertically fixed on the slide rail base (11); the two sides of the substrate base (7) are respectively installed on the two slide rails of the double slide rail through sliders, and a forming substrate (6) is fixed on the substrate base (7); the laser powder feeding system (3) is installed on the single slide rail through the slider; the motor (5) is used to drive the slider to move; The double spring layer plate (2) is mounted on the slide rail base (11), and the double slide rail passes through the double spring layer plate (2); the double spring layer plate (2) comprises an upper spring layer (201), a clamping plate (202), and a lower spring layer (203) which are fixedly connected in sequence from top to bottom.

2. The double spring layer buffer type simulated weightlessness 3D printing device according to claim 1, characterized in that: The ratio of the total elastic coefficient of the springs in the upper spring layer (201) to the total elastic coefficient of the springs in the lower spring layer (203) is 1 / 3 to 1 / 2.

3. The double spring layer buffer type simulated weightlessness 3D printing device according to claim 1, characterized in that: The upper spring layer (201) comprises two spring groups, each spring group corresponds to one of the double slide rails, each spring group comprises three springs, and the three springs are arranged in a triangle with the corresponding slide rail as the center; the lower spring layer (203) comprises four springs, and the four springs are arranged in a parallelogram.

4. The double spring layer buffer type simulated weightlessness 3D printing device according to claim 1, characterized in that: A mounting plate is fixed to the upper end of the upper spring layer (201), and a lower elastic buffer pad (9) is arranged on the mounting plate.

5. The double spring layer buffer type simulated weightlessness 3D printing device as claimed in claim 4, characterized in that: Vertical reinforcement plates are fixed around the sliding rail base (11), and the reinforcement plates are used to prevent the clamping plate (202) and the mounting plate from moving in a non-vertical direction.

6. The double spring layer buffer type simulated weightlessness 3D printing device according to claim 1, characterized in that: The substrate base (7) comprises an upper base and a lower base, wherein the upper base and the lower base are fixedly connected via an X-shaped cross fixing rod (106); the forming substrate (6) is fixed on the upper base, and the lower side of the lower base is covered with an upper elastic buffer pad (8).

7. The double spring layer buffer type simulated weightlessness 3D printing device according to claim 1, characterized in that: It also includes a control platform (12), which controls the movement of the slider via a motor (5); there are three motors (5), which are respectively fixed on the top ends of the two slide rails of the single slide rail and the double slide rail.

8. The double spring layer buffer type simulated weightlessness 3D printing device according to claim 1, characterized in that: The upper ends of the double slide rail and the single slide rail are both provided with a limit checkpoint (103), and an elastic gasket (104) is fixed on the lower side of the limit checkpoint (103).

9. The double spring layer buffer type simulated weightlessness 3D printing device according to any one of claims 1 to 8, characterized in that: The lengths of the double slide rails and the single slide rail are both 2000 mm to 4500 mm.

10. A double spring layer buffer type simulated weightlessness 3D printing method, implemented by the device according to any one of claims 1 to 9, characterized in that: The steps include: S1. Initially, the motor (5) controls the slider so that the substrate base (7) is located at the top of the double slide rails, and the laser powder feeding system (3) is correspondingly located above the forming substrate (6); S2, the substrate base (7) and the laser powder feeding system (3) are in free fall, and during the free fall, the forming substrate (6) and the laser powder feeding system (3) remain relatively still, so that the laser powder feeding system (3) prints on the forming substrate (6); S3, the substrate base (7) falls down and contacts the double spring layer plate (2), and the double spring layer plate (2) buffers and rebounds the substrate base (7). When the substrate base (7) is about to lose kinetic energy, the motor (5) controls the slider to return the substrate base (7) and the laser powder feeding system (3) to their initial positions; S4. Repeat steps S2 and S3 until the entire printing process is completed.

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