Stirring friction powder additive manufacturing device with stirring paddle

Abstract

The friction stir powder additive manufacturing device comprises a fixed shaft shoulder, a hollow shaft torque motor and a stirring shaft, the fixed shaft shoulder is provided with a discharging hole, the hollow shaft torque motor comprises a stator fixed to the fixed shaft shoulder and a rotor rotationally arranged in the stator, and a hollow shaft is fixed to the rotor; the stirring shaft comprises a charging barrel fixed to the hollow shaft and a spiral conveying rod arranged on the lower side of a bottom plate of the charging barrel, the spiral conveying rod is located in the discharging hole, and a discharging hole communicated with an inner cavity of the charging barrel and the spiral channel is formed in the bottom plate of the charging barrel; a movable shaft shoulder is arranged at the lower end of the spiral conveying rod; a stirring head is formed on the lower side of the movable shaft shoulder; a stirrer is arranged in the charging barrel and comprises a stirring paddle and a mounting rod connected to the stirring paddle, and the mounting rod is detachably mounted on the stator. Various powder additive raw materials and functional auxiliaries do not need to be mixed in advance, the number of devices is reduced, the production process can be shortened, and the production efficiency is improved.

Description

Technical Field

[0001] This utility model relates to a stirring friction powder additive manufacturing device carrying a stirring paddle. Background Technology

[0002] In recent years, friction stir additive manufacturing technology has emerged based on friction stir welding. It is a branch of 3D manufacturing technology. Friction stir additive manufacturing technology adopts different technical solutions depending on the raw materials used. The raw materials mainly include powders, granules, rods, wires, and plates. When using powders as raw materials, different powders need to be compounded to produce different types of products. Sometimes, some functional additives also need to be added. Therefore, it is necessary to first use a stirring device to mix various powders and functional additives to form a compound. Thus, in addition to conventional friction stir additive manufacturing equipment, a corresponding stirring device is also required. Moreover, after the mixing is completed, the compound material needs to be manually or mechanically fed into the friction stir additive manufacturing equipment, which increases the number of equipment and extends the production process. Utility Model Content

[0003] To address the issue of increased equipment requirements in existing friction stir additive manufacturing processes, which necessitates the separate preparation of agitation devices for mixing various powders and functional additives, this application proposes a friction stir powder additive manufacturing apparatus with a stirring paddle. The apparatus includes a fixed shaft shoulder, a hollow shaft torque motor, and a stirring shaft. The fixed shaft shoulder has a through-hole-shaped feed hole extending vertically. The hollow shaft torque motor includes a stator and a mover rotatably disposed inside the stator. A hollow shaft is fixedly mounted on the mover, and the stator is fixed to the fixed shaft shoulder. The stirring shaft includes a material cylinder and a spiral conveying rod disposed on the underside of the bottom plate of the material cylinder. The spiral conveying rod is located within the feed hole, forming a spiral channel between the spiral conveying rod and the inner wall of the feed hole. The upper end of the material cylinder has a feed inlet connecting the inside and outside of the cylinder, and the bottom plate of the material cylinder has a discharge hole connecting the inner cavity of the material cylinder and the spiral channel. The material cylinder is fixed to the hollow shaft.

[0004] The lower end of the screw conveyor is formed as a moving shoulder, and a stirring head is formed on the lower side of the moving shoulder; in the vertical direction, the lower surface of the moving shoulder extends downward beyond the lower end face of the fixed shoulder;

[0005] An agitator is installed inside the barrel. The agitator includes an agitator blade and a mounting rod connected to the agitator blade. The mounting rod extends upward from the feed inlet of the barrel and is detachably mounted on the stator. The mover can drive the agitator shaft to rotate. When the mover drives the agitator shaft to rotate, the agitator does not contact the agitator shaft.

[0006] This application can be connected to the fixed part of machining equipment such as friction stir welding machines, CNC milling machines, and CNC machining centers. The machining equipment is used to move the friction stir powder additive manufacturing device. Alternatively, a dedicated moving device can be installed to move the friction stir powder additive manufacturing device. During operation, the hollow shaft torque motor is started, causing the stirring shaft to rotate, which in turn drives the stirring head to rotate. The powder additive material in the barrel is discharged through the bottom of the spiral channel. The stirring head agitates the workpiece surface, and the moving shaft shoulder presses the powder additive material in and performs stirring welding to form an additive layer. The machining equipment drives the friction stir powder additive manufacturing device to move along the surface of the workpiece, gradually completing the repair or additive manufacturing of the workpiece.

[0007] When the stirring shaft rotates, the agitator rotates relative to the barrel, thereby mixing the powder additive materials inside the barrel. Therefore, when using this application for additive manufacturing, it is unnecessary to pre-mix various powder additive materials and functional additives. Simply add the various powder additive materials and functional additives to the barrel, and the stirring paddle will mix the materials in the barrel to form a composite material. This eliminates the need for separate mixing equipment for pre-mixing various powder additive materials and functional additives, thus reducing the number of equipment required. Since the various powder additive materials and functional additives are mixed simultaneously during production, the production process can be shortened, and production efficiency can be improved.

[0008] Furthermore, to ensure that the stirring paddle remains in its set position and avoids touching the inner wall of the barrel during the stirring process driven by the mover, at least two mounting rods are fixedly installed on the stirring paddle. These at least two mounting rods are evenly spaced around the central axis of the hollow shaft torque motor.

[0009] Furthermore, to improve the axial connection strength between the stator and the hollow shaft, the stator includes a cylindrical outer shell extending vertically, an upper end cover detachably mounted on the top of the outer shell, and a lower end cover detachably mounted on the bottom of the outer shell. The upper and lower end covers are rotatably connected to the hollow shaft via angular contact bearings. The stator is fixedly mounted on the shaft shoulder via the lower end cover, and the mounting rod is mounted on the upper end cover.

[0010] Furthermore, to reduce the number of parts, the lower end cap is integrally formed on the fixed shoulder.

[0011] Furthermore, for ease of installation, a mounting portion is formed on the stator or stator shoulder, which is used to connect the friction stir powder additive manufacturing apparatus to the machining equipment.

[0012] Furthermore, to prevent the powder additive material in the spiral channel from seeping into the interior of the hollow shaft torque motor, a seal is provided between the fixed shaft shoulder and the barrel.

[0013] Furthermore, the lower surface of the mixing head has downward-protruding mixing pins. These mixing pins increase the speed at which the mixing head penetrates the substrate, thereby improving operational efficiency.

[0014] Furthermore, to facilitate the feeding of different powder additive raw materials and functional additives into the barrel, at least two feed pipes extend into the barrel through the feed inlet.

[0015] Furthermore, to prevent the powder additive material in the spiral channel from overflowing outwards through the gap between the fixed shoulder and the workpiece, an anti-overflow plate is provided on the outer surface of the fixed shoulder. This anti-overflow plate is detachably mounted on the fixed shoulder, and its position can be adjusted vertically. The anti-overflow plate is located on the downstream side of the fixed shoulder. In this application, the side of the friction stir powder additive manufacturing apparatus facing the direction of movement during operation is referred to as the downstream side. When the friction stir powder additive manufacturing apparatus is operating, the powder additive material on the downstream side has not yet formed an additive layer and remains in powder form, making it prone to outward diffusion and loss. The anti-overflow plate effectively reduces the amount of powder additive material lost. When the friction stir powder additive manufacturing apparatus is operating, the height of the anti-overflow plate needs to be adjusted according to the thickness of the powder additive material on the workpiece surface to avoid affecting the normal operation of the friction stir powder additive manufacturing apparatus. Attached Figure Description

[0016] Figure 1 This is a structural schematic diagram of an embodiment of the present invention. Detailed Implementation

[0017] See Figure 1 A friction stir powder additive manufacturing apparatus with a stirring paddle includes a fixed shoulder 16, a hollow shaft torque motor 10, and a stirring shaft 20. The fixed shoulder 16 has a through-hole 165 extending vertically. The hollow shaft torque motor includes a stator 110 and a mover 13 rotatably disposed inside the stator 110. A hollow shaft 14 is fixedly mounted on the mover. The stator 110 is fixed to the fixed shoulder 16. The central axis 101 of the hollow shaft torque motor 10 extends vertically. Specifically, in this embodiment, the stator 110 includes a housing 11, an upper end cover 15, and a lower end cover 18. The housing 11 is cylindrical and extends vertically, with a winding 12 disposed on the inner side of the housing. The structure of the hollow shaft torque motor can be completed using existing mature technology and will not be described in detail.

[0018] An upper flange 111 and a lower flange 112 are respectively provided at the upper and lower ends of the outer casing. The upper flange 111 is located above the lower flange 112. The upper end cover has a first flange corresponding to the upper flange. The first bolt 152 fixes the first flange to the upper flange. The lower end cover has a second flange 181 corresponding to the lower flange. The second bolt 182 fixes the second flange to the lower flange, so that the upper end cover and the lower end cover can be detachably installed at the top and bottom of the outer casing, respectively.

[0019] The upper and lower ends of the outer casing are rotatably connected to the hollow shaft 14 via an upper angular contact bearing 31 and a lower angular contact bearing 32, respectively. In this embodiment, an upper flange 113 is provided on the upper part of the outer peripheral surface of the hollow shaft 14, and the upper end cover 15 abuts against the hollow shaft 14 via the upper angular contact bearing 31. The upper end cover has an inwardly protruding abutting flange 153, the lower surface of which is a downward-facing stepped surface. The abutting flange 153 presses against the upper side of the outer ring of the upper angular contact bearing via its lower surface, and the upper flange presses against the lower side of the inner ring of the upper angular contact bearing.

[0020] A stepped portion 114 is provided at the lower end of the hollow shaft 14. The stepped portion is formed by a radial inward indentation of the outer circumferential surface of the hollow shaft. The stepped portion has a downward-facing stepped surface. The lower end cover 18 abuts against the hollow shaft 14 via the lower angular contact bearing 32. The inner side of the lower end cover has an upward-facing abutting surface 184, which is an upward-facing stepped surface. The abutting surface 184 abuts against the lower side of the outer ring of the lower angular contact bearing, and the stepped portion 114 abuts against the upper side of the inner ring of the lower angular contact bearing.

[0021] The fixed-axis shoulder 16 includes a cylindrical body 160. In this embodiment, the lower end cap is integrally formed on the body 160. That is, the lower end cap is integrally formed on the fixed-axis shoulder.

[0022] The stirring shaft 20 includes a barrel 21 and a screw conveyor 24. The barrel is used to store powder additive raw materials. The barrel 21 has a bottom plate 23, and its upper end is open, forming a feed inlet 22 that connects the inside and outside of the barrel. The screw conveyor 24 is formed on the lower surface of the bottom plate. The screw conveyor 24 includes a rod body 241 extending downward in the vertical direction and helical blades 242 formed on the outer peripheral surface of the rod body. The lower end of the rod body forms a moving shoulder 25, and a stirring head 26 is formed on the lower side of the moving shoulder 25. In the vertical direction, the lower surface 251 of the moving shoulder extends downward beyond the lower end face 163 of the fixed shoulder 16. To facilitate stirring, a downwardly protruding stirring needle 27 is provided on the lower surface of the stirring head 26.

[0023] The spiral conveyor 24 is located inside the discharge hole 165, forming a spiral channel 166 between the spiral conveyor and the inner wall of the discharge hole. A discharge hole 231, connecting the inner cavity of the material cylinder to the spiral channel, is provided on the bottom plate 23 of the material cylinder. The material cylinder is fixed to the hollow shaft 14, and the material cylinder and the hollow shaft are coaxially arranged. The powder additive raw material inside the material cylinder can enter the spiral channel through the discharge hole and, under the push of the spiral conveyor, be discharged downwards from the lower end of the spiral channel. To maintain a seal, a sealing element 41 is provided between the material cylinder and the fixed shaft shoulder. Specifically, in this embodiment, the sealing element 41 is an O-ring rubber ring.

[0024] Specifically, in this embodiment, a key 17 is provided between the material cylinder 21 and the hollow shaft 14. A connecting flange 211 is provided at the upper end of the material cylinder, and a third bolt 212 fixes the connecting flange to the fixed part of the hollow shaft, allowing the stirring shaft 20 to be detachably mounted on the hollow shaft. The connecting flange is integrally formed on the material cylinder. It can be understood that, in another embodiment, a separate flange can also be welded to the material cylinder as a connecting flange.

[0025] An agitator 80 is installed inside the material cylinder 21. The agitator 80 includes an agitator 81 and a mounting rod 82 connected to the agitator 81. The mounting rod extends upward from the feed inlet of the material cylinder, then bends downward and is detachably mounted on the upper end cover of the stator via a fourth bolt 83. Specifically, in this embodiment, the agitator is a frame-type agitator, including six blades arranged symmetrically along the same plane. Therefore, in this embodiment, only two mounting rods 82 are provided, and the two mounting rods are symmetrically arranged with respect to the central axis of the hollow shaft torque motor, that is, the two mounting rods are evenly spaced with respect to the central axis of the hollow shaft torque motor. It is understood that in other embodiments, other forms of stirring paddles may be used, and three or more mounting rods may be set according to the structure of the stirring paddle, but generally no more than four mounting rods are required. Four mounting rods are sufficient to ensure the stability of the stirring paddle, and three rods are preferred. While ensuring stability, it is also convenient to adjust the installation position of the stirring paddle in the barrel. When the mover drives the stirring shaft to rotate, the stirrer does not contact the stirring shaft, so that the stirrer does not contact the barrel, thus avoiding excessive wear of the stirrer on the inner wall of the barrel and the stirrer itself.

[0026] To prevent the powder additive manufacturing material from diffusing outwards within the spiral channel and affecting its utilization rate, an anti-overflow plate 51 is installed on the outer surface of the main body 160. An elongated hole 52 is vertically formed in the anti-overflow plate 51, and an adjusting screw 53 passes through this hole and is screwed onto the main body. When the height of the anti-overflow plate needs to be adjusted, the adjusting screw is loosened to adjust the height, and then tightened again. The anti-overflow plate 51 is specifically installed on the downstream side of the main body. The side of the friction stir powder additive manufacturing device facing the direction of movement during operation is called the downstream side. In the attached diagram, arrow X indicates the direction of movement of the friction stir powder additive manufacturing device during operation.

[0027] To facilitate the installation of the friction stir powder additive manufacturing apparatus on machining equipment such as friction stir welding machines, CNC milling machines, and CNC machining centers, eight connecting ears 185 are provided on the second flange 181. These connecting ears are formed by radially protruding outwards from the outer circumferential surface of the second flange, and each connecting ear 185 has a mounting hole 186. The eight connecting ears together form a connecting part for connection to machining equipment with a corresponding connecting mechanism. It is understood that in another embodiment, the second flange can also be expanded outwards as a whole to form the mounting part. Since in this embodiment, the second flange serves as both part of the stator and is integrally formed with the stator shoulder, the mounting part is formed both on the stator and on the stator shoulder. Of course, in other embodiments, the outer shell, the upper end cover, or the stator shoulder can also be used as the connecting part.

[0028] Two feed pipes 61 extend into the barrel. Depending on the requirements, one or two feed pipes can be used to feed the same powder additive material into the barrel, or two different powder additive materials can be fed into the barrel.

[0029] During operation, the hollow shaft torque motor is started, causing the stirring shaft 20 to rotate and pressing the stirring head 26 into the workpiece 71. The powder additive material in the barrel enters the spiral channel through the discharge hole. Under the push of the spiral conveyor rod 24, the powder additive material moves downward and is discharged. Then, under the pressure of the moving shaft shoulder, it is stirred and welded with the surface layer of the workpiece to continuously form the additive layer 72. The lower end face 163 of the fixed shaft shoulder 16 smooths the surface layer of the additive workpiece.

[0030] When using two different powder additive raw materials, each raw material can be fed into the cylinder through a separate feeding pipe. When the rotor of the hollow shaft torque motor drives the stirring shaft to rotate, the stirring paddle rotates relative to the cylinder, mixing the powder additive raw materials to form a composite material. This eliminates the need for pre-mixing the powder additive raw materials, thus eliminating the need for corresponding mixing equipment. The number of raw material pipes can be set according to the type of powder additive raw material and the type of functional additives.

Claims

1. A stirring friction powder additive manufacturing apparatus carrying a stirring paddle, characterized in that, The device includes a fixed shaft shoulder, a hollow shaft torque motor, and a stirring shaft. The fixed shaft shoulder has a through-hole-shaped discharge hole extending vertically. The hollow shaft torque motor includes a stator and a mover rotatably disposed inside the stator. A hollow shaft is fixedly mounted on the mover, and the stator is fixed to the fixed shaft shoulder. The stirring shaft includes a material cylinder and a spiral conveying rod disposed on the lower side of the bottom plate of the material cylinder. The spiral conveying rod is located inside the discharge hole, forming a spiral channel between the spiral conveying rod and the inner wall of the discharge hole. The upper end of the material cylinder has a feed inlet communicating with the inside and outside of the material cylinder, and the bottom plate of the material cylinder has a discharge hole communicating with the inner cavity of the material cylinder and the spiral channel. The material cylinder is fixed to the hollow shaft. The lower end of the screw conveyor is formed as a moving shoulder, and a stirring head is formed on the lower side of the moving shoulder; in the vertical direction, the lower surface of the moving shoulder extends downward beyond the lower end face of the fixed shoulder; An agitator is installed inside the barrel. The agitator includes an agitator blade and a mounting rod connected to the agitator blade. The mounting rod extends upward from the feed inlet of the barrel and is detachably mounted on the stator. The mover can drive the agitator shaft to rotate. When the mover drives the agitator shaft to rotate, the agitator does not contact the agitator shaft.

2. The friction stir powder additive manufacturing apparatus according to claim 1, characterized in that, At least two mounting rods are fixedly installed on the impeller, and these at least two mounting rods are evenly spaced around the central axis of the hollow shaft torque motor.

3. The friction stir powder additive manufacturing apparatus according to claim 1, characterized in that, The stator includes a cylindrical housing extending vertically, an upper end cover detachably mounted on the top of the housing, and a lower end cover detachably mounted on the bottom of the housing. The upper and lower end covers are rotatably connected to the hollow shaft via angular contact bearings. The stator is fixedly mounted on the shaft shoulder via the lower end cover, and the mounting rod is mounted on the upper end cover.

4. The friction stir powder additive manufacturing apparatus according to claim 3, characterized in that, The lower end cap is integrally formed on the fixed shoulder.

5. The friction stir powder additive manufacturing apparatus according to claim 1, characterized in that, A mounting portion is formed on the stator or the fixed shaft shoulder, which is used to connect the friction stir powder additive manufacturing apparatus to the machining equipment.

6. The friction stir powder additive manufacturing apparatus according to claim 1, characterized in that, A seal is provided between the fixed shoulder and the barrel.

7. The friction stir powder additive manufacturing apparatus according to claim 1, characterized in that, The lower surface of the stirring head has downward-protruding stirring needles.

8. The friction stir powder additive manufacturing apparatus according to claim 1, characterized in that, At least two feed pipes extend into the feed cylinder through the feed inlet.

9. The friction stir powder additive manufacturing apparatus according to claim 1, characterized in that, An anti-overflow plate is provided on the outer side of the fixed shaft shoulder. The anti-overflow plate is detachably installed on the fixed shaft shoulder, and the position of the anti-overflow plate can be adjusted in the vertical direction. The anti-overflow plate is located on the downstream side of the fixed shaft shoulder.

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