Metal 3D printed part residual stress elimination device

Abstract

The application discloses a metal 3D printing part residual stress elimination device, and relates to the technical field of additive manufacturing post-processing, which comprises a support, a platform and a vibrating bin, the vibrating bin is through the middle of the platform and is movably connected with the platform, the support is connected at both ends of the platform, the platform is provided with a Z-axis directional vibration mechanism, the lower part of the vibrating bin is provided with a double-oscillating-rod vibration mechanism, the upper part of the double-oscillating-rod vibration mechanism is provided with a self-adaptive clamping jaw mechanism and a thimble mechanism. The application ensures the stability of the workpiece through self-adaptive clamping, the synergistic effect of Z-axis directional vibration (providing strong vertical impact, and the amplitude can be accurately adjusted on line) and independently controllable double-oscillating-rod multidirectional vibration, the composite vibration mode efficiently excites the metal internal microstructure in three-dimensional space, promotes the full release of residual stress, and through the precise limiting and damping design, the effective energy transmission and the smooth operation of the equipment are ensured, the whole process is efficient and controllable, and the metal 3D printing part with a complex shape is suitable.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of post-processing of additive manufacturing, in particular to a residual stress relieving device for metal 3D printed parts. BACKGROUND

[0002] The metal 3D printed parts have high residual stress in the Z-axis direction due to layer-by-layer accumulation, which is easy to cause deformation and cracking. The traditional heat treatment method has high energy consumption and long cycle; the mechanical vibration method has the problems of uncontrollable direction and inaccurate frequency adjustment. The limitations of the prior art are that the general vibration table cannot realize Z-axis directional vibration; the vibration amplitude / frequency adjustment depends on the replacement of hardware, and the flexibility is poor; the customized fixture is required for complex workpieces, and the adaptability is insufficient.

[0003] Therefore, a residual stress relieving device for metal 3D printed parts is provided. SUMMARY

[0004] The purpose of the present application is to provide a residual stress relieving device for metal 3D printed parts to solve the problems in the background art.

[0005] In order to achieve the above purpose, the present application provides the following technical scheme: a residual stress relieving device for metal 3D printed parts, comprising a support, a platform and a vibration bin, the vibration bin is through the middle of the platform and is movably connected with the platform, the support is connected at both ends of the platform, the platform is provided with a Z-axis directional vibration mechanism, the lower part of the vibration bin is provided with a double pendulum vibration mechanism, the upper part of the double pendulum vibration mechanism is provided with a self-adaptive clamping jaw mechanism and a ejector pin mechanism;

[0006] The Z-axis directional vibration mechanism comprises a first limiting column, a second limiting column, a first damping spring, a second damping spring, a rocker motor and an adjustable vibration rocker, the support is a vertical structure, the cross section of the upper and lower ends of the support is Y-shaped, the first limiting column is provided at both ends of the platform, the first limiting column penetrates the platform and is connected with the support at the end, the first limiting column is sleeved with the first damping spring on the surface, the outer surface of the vibration bin is connected with the platform through a spring, four second limiting columns are evenly arranged on the upper surface of the platform along the circumference of the vibration bin, the second limiting column abuts against the surface of the vibration bin, the second limiting column is sleeved with the second damping spring on the outer surface, and the rocker motor is fixedly connected to the front and rear surfaces of the platform.

[0007] The adjustable vibration rocker comprises a hollow rocker shaft, a top screw at the top of the rocker shaft, a first motor in the rocker shaft, a sliding rail along the outer periphery of the rocker shaft, a lead screw connected with the output end of the first motor, and a counterweight sliding block slidingly connected to the sliding rail and driven by the lead screw through the first motor, and the rocker shaft is fixedly connected with the output end of the rocker motor through the top screw.

[0008] Further preferably, the double pendulum vibrating mechanism comprises a mounting table at the bottom of the vibrating bin, a rotating motor one and a rotating motor two fixedly connected to the mounting table, a first driving gear and a second driving gear connected to the output ends of the rotating motor one and the rotating motor two respectively, a first pendulum and a second pendulum rotatably connected to the middle part of the mounting table, the first pendulum is provided with a first transmission gear at the end of the rotating shaft, the second pendulum is provided with a second transmission gear at the end of the rotating shaft, the first transmission gear is in mesh with the first driving gear, and the second transmission gear is in mesh with the second driving gear.

[0009] Preferably, the first pendulum and the second pendulum have the same weight.

[0010] Preferably, the self-adaptive clamping jaw mechanism comprises a disc base, a second motor fixedly connected to the bottom of the disc base, a disc wheel sleeved on the disc base and connected to the output end of the second motor, a sliding clamping jaw in sliding connection with the disc wheel, and a guide rail cover plate covering above the disc wheel.

[0011] Preferably, the top pin mechanism comprises guide rails fixedly connected to the upper part of the inner wall of the vibrating bin, sliding pin blocks in sliding connection with the guide rails, and steel pins detachably arranged on the sliding pin blocks.

[0012] Preferably, the number of guide rails is four, and the guide rails are connected to the inner wall of the vibrating bin through screws.

[0013] Preferably, the sliding pin block is configured to comprise an upper pin block and a lower pin block, the upper pin block and the lower pin block are connected through a mortise and tenon structure, one side of the upper pin block and the lower pin block is provided with a threaded hole, and the steel pin is threadedly connected in the threaded hole of the upper pin block and the lower pin block.

[0014] Preferably, the outer surface of the vibrating bin is provided with a bin door.

[0015] In the above technical solution, the present application has the following technical effects and advantages:

[0016] 1. The present application can more thoroughly eliminate the residual stress in the complex metal 3D printed parts through the synergistic effect of Z-axis directional vibration and multi-directional pendulum vibration; the Z-axis amplitude can be adjusted steplessly online; the double pendulum rotating speed and phase are independently adjustable, and can generate multiple vibration modes; the clamping jaw and the top pin can be self-adaptive to different workpieces; the precise limiting and damping design, the pendulum dynamic balance design and the stable top pin connection mode ensure the smooth operation of the equipment, the effective transmission of the vibration energy, and the protection of the workpiece and the equipment itself; the self-adaptive clamping jaw and the adjustable top pin design can process metal printed parts of various shapes and sizes; the design of the rocker arm and the steel pin considers the convenience of installation, adjustment and replacement; these effects jointly improve the efficiency, quality and application range of residual stress elimination of metal 3D printed parts. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed in the embodiments. Obviously, the drawings described below only show some embodiments of the present application, and other drawings can also be obtained by those skilled in the art based on these drawings.

[0018] Figure 1 Schematic diagram of the three-dimensional structure of the present application;

[0019] Figure 2 Schematic diagram of the planar layout of the present application;

[0020] Figure 3 Schematic diagram of the split structure of the present application;

[0021] Figure 4 Schematic diagram of the three-dimensional structure of the adjustable vibration rocker of the present application;

[0022] Figure 5 Schematic diagram of the planar structure of the adjustable vibration rocker of the present application;

[0023] Figure 6 Schematic diagram of the double pendulum vibration mechanism structure of the present application;

[0024] Figure 7 Schematic diagram of the embodiment of the present application;

[0025] Figure 8 Schematic diagram of the self-adaptive clamping jaw mechanism structure of the present application;

[0026] Figure 9 Schematic diagram of the thimble mechanism structure of the present application;

[0027] Figure 10 Schematic diagram of the planar structure of the sliding needle block of the present application.

[0028] Explanation of reference signs:

[0029] 1, support; 2, platform; 3, vibration bin; 4, first limiting column; 5, second limiting column; 6, first damping spring; 7, second damping spring; 8, rocker motor; 9, adjustable vibration rocker; 10, bin door; 901, rocker shaft; 902, jackscrew; 903, first motor; 904, sliding rail; 905, lead screw; 906, counterweight sliding block; 1001, mounting table; 1002, rotary motor one; 1003, rotary motor two; 1004, first drive gear; 1005, second drive gear; 1006, first pendulum; 1007, second pendulum; 1008, first transmission gear; 1009, second transmission gear; 1101, disc base; 1102, second motor; 1103, disc wheel; 1104, sliding clamping jaw; 1105, guide rail cover plate; 1201, guide rail; 1202, sliding needle block; 1203, steel needle. DETAILED DESCRIPTION

[0030] In order for those skilled in the art to better understand the technical solutions of the present application, the present application will be further described in detail below with reference to the drawings.

[0031] As shown in Figures 1-3 A metal 3D printed part residual stress elimination device, including a support 1, a platform 2 and a vibrating bin 3, the vibrating bin 3 penetrates the middle of the platform 2 and is movably connected therewith, the support 1 is connected at both ends of the platform 2, the platform 2 is provided with a Z-axis directional vibration mechanism, the lower part of the vibrating bin 3 is provided with a double pendulum vibration mechanism, the upper part of the double pendulum vibration mechanism is provided with a self-adaptive jaw mechanism and a center pin mechanism; the Z-axis directional vibration mechanism provides a strong impact in the vertical direction and the double pendulum vibration mechanism can more effectively excite and release the residual stress in different directions inside the metal printed part, and the jaws and the center pin can be self-adaptive to different workpieces.

[0032] The Z-axis directional vibration mechanism includes a first limiting column 4, a second limiting column 5, a first damping spring 6, a second damping spring 7, a rocker motor 8 and an adjustable vibrating rocker 9, the support 1 is a vertical structure, the cross section of the upper and lower ends thereof is Y-shaped, the first limiting column 4 is arranged at both ends of the platform 2, the first limiting column 4 penetrates the platform 2 and is connected with the support 1 at the end thereof, the first limiting column 4 is sleeved with the first damping spring 6 on the surface thereof, the vibrating bin 3 is connected with the platform 2 through a spring on the outer surface thereof, four second limiting columns 5 are evenly arranged on the upper surface of the platform 2 along the circumference of the vibrating bin 3, the second limiting columns 5 abut against the surface of the vibrating bin 3, the second limiting columns 5 are sleeved with the second damping springs 7 on the outer surfaces thereof, and the rocker motor 8 is fixedly connected to the front and rear surfaces of the platform 2; the Y-shaped support 1 can provide stable support, the limiting columns and the damping springs effectively constrain the movement direction (mainly in the Z-axis) of the platform 2 and the vibrating bin 3, reduce unnecessary lateral shaking, ensure that the vibration energy is more effectively transmitted to the workpiece, and significantly reduce the transmission of vibration to the outside, thereby protecting the equipment foundation and the surrounding environment.

[0033] As shown in Figure 4 , 5 The adjustable vibrating rocker 9 includes a hollow rocker shaft 901, a top screw 902 at the top of the rocker shaft 901, a first motor 903 inside the rocker shaft 901, a sliding rail 904 along the outer circumference of the rocker shaft 901, a lead screw 905 connected with the output end of the first motor 903, and a counterweight sliding block 906 driven by the lead screw 905 through the first motor 903 to drive the sliding rail 904, and the rocker shaft 901 is fixedly connected with the output end of the rocker motor 8 through the top screw 902; the counterweight sliding block 906 drives the lead screw 905 to move through the first motor 903, without the need to stop or replace parts, the eccentricity (i.e. amplitude) of the rocker can be adjusted online and accurately, different sizes, weights and stress states of workpieces can be adapted, fine control of vibration energy can be realized, and the operation is convenient and efficient.

[0034] Further, as shown in Figure 6 , the double pendulum vibration mechanism includes a mounting table 1001 at the bottom of the vibration bin 3, a rotating motor one 1002 and a rotating motor two 1003 fixedly connected to the mounting table 1001, a first drive gear 1004 and a second drive gear 1005 connected to the output ends of the rotating motor one 1002 and the rotating motor two 1003 respectively, a first pendulum 1006 and a second pendulum 1007 rotatably connected to the middle part of the mounting table 1001, the first pendulum 1006 is provided with a first transmission gear 1008 at the end of the rotating shaft, the second pendulum 1007 is provided with a second transmission gear 1009 at the end of the rotating shaft, the first transmission gear 1008 is engaged with the first drive gear 1004, and the second transmission gear 1009 is engaged with the second drive gear 1005; the first pendulum 1006 and the second pendulum 1007 have the same weight; two independent motors drive and control the two pendulums respectively, allowing independent adjustment of the rotating speed, phase and even start and stop of the two pendulums, generating eccentric force to drive the vibration bin 3 to vibrate, and by controlling the speed difference of the two motors, the two pendulums can produce different angle differences; as shown in Figure 7 , the leftmost side, the two pendulums are on the same side at this time, the vibration is the largest, when the speed difference starts to produce, gradually reaches the rightmost side as shown in Figure 7 , and starts to rotate at the same speed again, since the two pendulums have the same weight, the vibration amplitude gradually decreases, this design can flexibly generate various vibration modes (such as forward rotation, reverse rotation, asynchronous rotation), and can generate complex and multi-directional excitation force field in the vibration bin 3, which can more effectively "stir" and release the anisotropic residual stress inside the workpiece; the two pendulums have the same weight: it helps to maintain the dynamic balance of the mechanism during operation, reduces unnecessary vibration and noise, and improves the stability and service life of the equipment.

[0035] Preferably, as shown in Figure 8 , the self-adaptive clamping jaw mechanism includes a disc base 1101, a second motor 1102 fixedly connected to the bottom of the disc base 1101, a disc wheel 1103 sleeved and embedded on the disc base 1101 and connected to the output end of the second motor 1102, a sliding clamping jaw 1104 in sliding connection with the disc wheel 1103, and a guide cover plate 1105 covering above the disc wheel 1103; the upper surface of the disc wheel 1103 has a spiral track, and the bottom of the sliding clamping jaw 1104 has a clamping groove clamped on the spiral track; the disc wheel 1103 is driven by the second motor 1102 to drive the sliding clamping jaw 1104 to move synchronously in the track, which can automatically adapt to different shapes and sizes of metal printed parts for clamping and fixing, especially suitable for complex shape, multi-variety and small-batch 3D printed parts.

[0036] As shown in Figure 9 , 10As shown, the ejector pin mechanism includes a guide rail 1201 fixedly connected to the upper part of the inner wall of the vibration bin 3, a sliding pin block 1202 slidingly connected to the guide rail 1201, and a steel pin 1203 detachably connected to the sliding pin block 1202; the guide rail 1201 is four turns in number, and the guide rail 1201 is connected to the inner wall of the vibration bin 3 by screws; the sliding pin block 1202 is configured to include an upper pin block and a lower pin block, the upper pin block and the lower pin block are connected by a mortise and tenon structure, one side of the upper pin block and the lower pin block is provided with a threaded hole, and the steel pin 1203 is threadedly connected in the threaded hole of the upper pin block and the lower pin block; the sliding pin block 1202 can flexibly arrange multiple support points on the guide rail 1201 according to the bottom surface profile of the workpiece and the position required to be supported; the steel pin 1203 is detachable, so that different lengths of the steel pin 1203 can be replaced according to the height of the workpiece and the requirement of the support point; the mortise and tenon connection of the upper pin block and the lower pin block and the threaded connection of the steel pin 1203 provide double stability. The mortise and tenon structure ensures that the upper and lower pin blocks are tightly combined, and the threaded connection ensures that the steel pin 1203 will not loosen in severe vibration. At the same time, this design also facilitates the disassembly and replacement of a specific damaged steel pin 1203 or pin block part, and is convenient and low in cost to maintain.

[0037] Further, the outer surface of the vibration bin 3 is provided with a bin door 10.

[0038] Working process:

[0039] 1. Workpiece placement and preparation: open the bin door 10 on the outer surface of the vibration bin 3, and place the metal 3D printed part to be processed into the vibration bin 3 and place it on the adaptive jaw mechanism and the ejector pin mechanism area above the double pendulum vibration mechanism;

[0040] 2. Workpiece clamping and fixing: start the second motor 1102 of the adaptive jaw mechanism, the second motor 1102 drives the disc wheel 1103 connected to the output end to rotate, the upper surface of the disc wheel 1103 has a spiral track, and the sliding jaw 1104 slidingly connected to the disc wheel 1103 has a clamping groove at the bottom, which is clamped on the spiral track, and as the disc wheel 1103 rotates, the spiral track drives the sliding jaw 1104 to move inward or outward along the path on the disc base 1101 (radial movement), multiple sliding jaws 1104 move synchronously, automatically fold and clamp different shapes and sizes of metal printed parts, and ensure their stability in subsequent severe vibration;

[0041] 3. Adjustment of the ejector pin mechanism: adjust the position of the sliding pin block 1202 by opening the bin door 10 according to the stress problem fed back by the first vibration;

[0042] 4. Confirming the firm clamping of the workpiece and closing the bin door 10 of the vibration bin 3;

[0043] 5、Start Z-axis directional vibration: start the rocker motor 8 fixedly connected to the front and back of the platform 2, the rocker motor 8 drives the rocker shaft 901 of the adjustable vibration rocker 9 fixedly connected (through the top wire 902) at its output end to rotate, the counterweight sliding block 906 on the rocker shaft 901 (the position can be adjusted by moving the lead screw 905 on the sliding rail 904 by the first motor 903) generates centrifugal force; before vibration, according to the weight of the workpiece and the required initial amplitude, the initial amplitude is set by moving the counterweight sliding block 906 to change its distance from the center of rotation (eccentricity) by the first motor 903 driving the lead screw 905; during vibration, according to sensor feedback or pre-set program, the position of the counterweight sliding block 906 is fine-tuned in real time by controlling the first motor 903, the amplitude (i.e. vibration intensity) is accurately adjusted, and fine control of vibration energy is realized; the excitation force is transmitted to the platform 2 through the rocker shaft 901, the first limiting column 4 (penetrating the platform 2, the end connected to the support 1) at both ends of the platform 2 and the first damping spring 6 sleeved on the surface thereof constrain the movement of the platform 2 mainly in the Z-axis direction, suppress transverse shaking, and absorb / dissipate part of the vibration energy, reducing the vibration transmitted to the support 1, the outer surface of the vibration chamber 3 is connected to the platform 2 through a spring, receiving Z-direction vibration, the four second limiting columns 5 (abutting the surface of the vibration chamber 3) evenly arranged on the upper surface of the platform 2 and the second damping spring 7 sleeved on the outer surface thereof further constrain the transverse displacement of the vibration chamber 3, ensuring that the vibration energy is efficiently and directionally (mainly in the Z-axis) transmitted to the workpiece in the vibration chamber 3, and protecting the structure of the platform 2. The support 1 with Y-shaped cross-section provides stable basic support, the workpiece receives strong and directional vertical impact vibration, and starts to release residual stress in the Z-axis direction;

[0044] 6、Start double pendulum vibration: start the rotary motor one 1002 and the rotary motor two 1003 fixedly connected to the mounting table 1001 at the bottom of the vibration chamber 3, the rotary motor one 1002 drives the first drive gear 1004 at its output end to rotate, the first drive gear 1004 meshes with the first transmission gear 1008 at the end of the rotating shaft of the first pendulum 1006, thereby driving the first pendulum 1006 to rotate in the middle of the mounting table 1001, and by the same token, the rotary motor two 1003 drives the second drive gear 1005 to rotate, and through the meshing second transmission gear 1009, the second pendulum 1007 is driven to rotate, and by independently controlling the rotation speed, rotation direction (forward / reverse) and start / stop of the rotary motor one 1002 and the rotary motor two 1003, the motion state of the two pendulums can be flexibly controlled.

[0045] 7、Vibration stops and workpiece is taken out.

[0046] In summary, the application ensures the stability of the workpiece by self-adaptive clamping, the synergistic effect of Z-axis directional vibration (providing strong vertical impact, and the amplitude can be accurately adjusted online) and independently controllable double-oscillator multi-directional vibration, and such a composite vibration mode efficiently excites the microstructure inside the metal in three-dimensional space, promotes the full release of residual stress, and ensures effective energy transmission and smooth operation of the equipment through precise limiting and shock-absorbing design. The whole process is efficient and controllable, and is suitable for 3D metal printing parts with complex shapes.

[0047] The above has described certain exemplary embodiments of the application by way of illustration only, and it is needless to say that the described embodiments can be modified in various ways without departing from the spirit and scope of the application for those skilled in the art. Therefore, the above drawings and descriptions are illustrative in nature and should not be understood as limiting the scope of protection of the claims of the application.

Claims

1. A device for eliminating residual stress of metal 3D printed parts, characterized by: The invention comprises a bracket (1), a platform (2) and a vibration chamber (3), wherein the vibration chamber (3) passes through the middle of the platform (2) and is movably connected thereto, the bracket (1) is connected to both ends of the platform (2), a Z-axis directional vibration mechanism is provided on the platform (2), a double pendulum vibration mechanism is provided at the bottom of the vibration chamber (3), and an adaptive clamping claw mechanism and an ejector pin mechanism are provided above the double pendulum vibration mechanism; The Z-axis directional vibration mechanism comprises a first limiting column (4), a second limiting column (5), a first damping spring (6), a second damping spring (7), a rocker motor (8) and an adjustable vibration rocker (9); the bracket (1) is a vertical structure, and its upper and lower ends have Y-shaped cross-sections; the first limiting column (4) is provided at both ends of the platform (2); the first limiting column (4) passes through the platform (2) and its end is connected to the bracket (1); the surface of the first limiting column (4) is sleeved with a first damping spring (6); the outer surface of the vibration bin (3) is connected to the platform (2) through a spring; the upper surface of the platform (2) is evenly provided with four second limiting columns (5) along the circumference of the vibration bin (3); the second limiting column (5) abuts against the surface of the vibration bin (3); the outer surface of the second limiting column (5) is sleeved with a second damping spring (7); the front and rear surfaces of the platform (2) are fixedly connected with a rocker motor (8); The adjustable vibrating rocker arm (9) comprises a hollow rocker arm shaft (901), a top screw (902) at the top of the rocker arm shaft (901), a first motor (903) inside the rocker arm shaft (901), a slide rail (904) along the outer periphery of the rocker arm shaft (901), a screw rod (905) connected to the output end of the first motor (903), and a counterweight slider (906) slidably connected to the slide rail (904) and driven by the screw rod (905) driven by the first motor (903). The rocker arm shaft (901) is fixedly connected to the output end of the rocker arm motor (8) via the top screw (902).

2. A residual stress relief device for metal 3D printed parts according to claim 1, characterized in that: The double-pendulum vibration mechanism comprises a mounting platform (1001) located at the bottom of the vibration bin (3), a rotating motor 1 (1002) and a rotating motor 2 (1003) fixedly connected to the mounting platform (1001), a first driving gear (1004) and a second driving gear (1005) respectively connected to the output ends of the rotating motor 1 (1002) and the rotating motor 2 (1003), a first pendulum (1006) and a second pendulum (1007) rotatably connected to the middle of the mounting platform (1001), a first transmission gear (1008) being provided at the end of the rotating shaft of the first pendulum (1006), a second transmission gear (1009) being provided at the end of the rotating shaft of the second pendulum (1007), the first transmission gear (1008) being meshed with the first driving gear (1004), and the second transmission gear (1009) being meshed with the second driving gear (1005).

3. The residual stress relief device for metal 3D printed parts according to claim 2, characterized in that: The first pendulum (1006) and the second pendulum (1007) have the same weight.

4. The residual stress relief device for metal 3D printed parts according to claim 1, characterized in that: The adaptive clamping mechanism comprises a disc base (1101), a second motor (1102) fixedly connected to the bottom of the disc base (1101), a disc wheel (1103) sleeved on the disc base (1101) and connected to the output end of the second motor (1102), a sliding clamping jaw (1104) slidably connected to the disc wheel (1103), and a guide rail cover (1105) arranged above the disc wheel (1103).

5. The residual stress relief device for metal 3D printed parts according to claim 1, characterized in that: The ejector mechanism comprises a guide rail (1201) fixedly connected to the upper inner wall of the vibration chamber (3), a sliding needle block (1202) slidably connected to the guide rail (1201), and a steel needle (1203) detachable from the sliding needle block (1202).

6. The residual stress relief device for metal 3D printed parts according to claim 5, characterized in that: The guide rails (1201) are four in number, and the guide rails (1201) are connected to the inner wall of the vibration chamber (3) via screws.

7. The residual stress relief device for metal 3D printed parts according to claim 5, characterized in that: The sliding needle block (1202) is configured to include an upper needle block and a lower needle block, the upper needle block and the lower needle block are connected by a mortise and tenon structure, a threaded hole is provided on one side of the upper needle block and the lower needle block, and the steel needle (1203) is threadedly connected in the threaded holes of the upper needle block and the lower needle block.

8. A device for eliminating residual stress of a metal 3D printed part according to any one of claims 1 to 7, characterized in that: A chamber door (10) is provided on the outer surface of the vibration chamber (3).

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