阅读说明：本技术 一种多激光同轴送丝增材制造设备及送丝方法 (Multi-laser coaxial wire feeding additive manufacturing equipment and wire feeding method ) 是由 侯帅 王万 穴洪涛 于 2019-09-24 设计创作，主要内容包括：本发明提供了一种多激光同轴送丝增材制造设备及送丝方法,包括：气体密封箱和其内的运动机构总成。总成包括送丝装置、激光装置、旋转装置以及三个模组。三个模组分别为可沿着X轴、Y轴、Z轴移动。工作台设置在由第一模组和第二模组成的平台上,旋转装置设置在工作台上。送丝装置包括送丝盘和垂直于工作台的送丝器,送丝器固定于第三模组。激光装置的多个激光头沿着送丝器的周向排列,由激光头的喷嘴射出的激光与送丝器的中心轴有设定夹角,设定夹角的角度可调节,多个激光头的喷嘴射出的多束激光交汇于同一个光斑,光斑位于送丝器的中心轴上。本发明的增材制造设备能够在惰性气体密封的情况下,进行钛金属3D打印。(The invention provides multi-laser coaxial wire feeding additive manufacturing equipment and a wire feeding method, wherein the equipment comprises: a gas seal box and a motion mechanism assembly therein. The assembly comprises a wire feeding device, a laser device, a rotating device and three modules. The three modules can move along the X-axis, the Y-axis and the Z-axis respectively. The workbench is arranged on a platform consisting of a first module and a second module, and the rotating device is arranged on the workbench. The wire feeding device comprises a wire feeding disc and a wire feeder perpendicular to the workbench, and the wire feeder is fixed on the third module. A plurality of laser heads of the laser device are arranged along the circumferential direction of the wire feeder, a set included angle is formed between laser emitted by a nozzle of each laser head and a central shaft of the wire feeder, the set included angle is adjustable, a plurality of laser emitted by the nozzles of the plurality of laser heads are converged at the same light spot, and the light spot is positioned on the central shaft of the wire feeder. The additive manufacturing equipment can perform titanium metal 3D printing under the condition of inert gas sealing.)

1. The utility model provides a coaxial wire feed increase material manufacturing equipment of many lasers which characterized in that mainly includes:

the inside of the gas seal box is a sealed environment filled with inert gas;

the moving mechanism assembly is positioned in the gas seal box and comprises a wire feeding device, a laser device, a rotating device and three modules; the three modules are respectively a first module capable of moving along the X-axis direction, a second module capable of moving along the Y-axis direction and a third module capable of moving along the Z-axis direction, the workbench is arranged on a platform consisting of the first module and the second module, and the rotating device is arranged on the workbench; the wire feeding device comprises a wire feeding disc and a wire feeder vertical to the workbench, and the wire feeder is fixed on the third module; a plurality of laser heads of laser device along the circumference of sending a ware is arranged, by the laser that the nozzle of laser head jetted out with send the center pin of a ware to have the settlement contained angle, the angle adjustable of setting for the contained angle, the multi-beam laser that the nozzle of a plurality of laser heads jetted out intersects in same facula, the facula is located send on the center pin of a ware.

2. The multi-laser coaxial wire feed additive manufacturing apparatus of claim 1, wherein the rotating device is rotatable along an X-axis and/or a Y-axis.

3. The multi-laser coaxial wire feed additive manufacturing device of claim 2, wherein the laser head has a fiber interface from which laser light is transmitted to the nozzle and a cooling channel having a water inlet and a water outlet at the same end as the fiber interface.

4. The multi-laser coaxial wire feed additive manufacturing apparatus of any one of claims 1 to 3, wherein the laser head has a spot adjustment knob for adjusting a position of a focusing lens to adjust a size of a spot.

5. The multi-laser coaxial wire feeding additive manufacturing equipment according to claim 4, wherein the interior of the wire feeder and the laser head is a hollow protection cavity, and the wire feeder and the laser head are respectively provided with an air inlet device for introducing inert gas into the protection cavity.

6. The multi-laser coaxial wire feed additive manufacturing device according to claim 1, wherein a wire drawing mechanism is arranged in the wire feeder, the wire passes through a guide wheel from the wire feeding disc to reach the wire drawing mechanism, and the wire drawing mechanism comprises a driving device, a driven pinch roller, a sensor, a wire feeding correction pipe and a wire discharging correction pipe.

7. The multi-laser coaxial wire feed additive manufacturing apparatus of claim 3, further comprising:

the transition cabin is a hollow cabin body, a workpiece is placed in the hollow cabin body, the hollow cabin body is vacuumized through a vacuum pump, protective gas is filled, and the inner cabin door is opened to realize a feeding process;

and the auxiliary box body is internally provided with a gas circulation and regeneration system and a laser, the gas circulation and regeneration system is connected with the gas seal box through a pipeline, and the laser is connected with the optical fiber interface through an optical fiber.

8. The multi-laser coaxial wire feed additive manufacturing apparatus of claim 1, wherein the laser heads are low power laser apparatuses, and the number of the laser heads is at least two.

9. The multi-laser coaxial wire feed additive manufacturing device according to claim 4, wherein the laser head is rotatably connected to the wire feeder by a screw, and the screw is perpendicular to a central axis of the wire feeder to adjust an angle of the set included angle.

10. An additive manufacturing wire feeding method for controlling the apparatus of claim 1, comprising an initial positioning step of initial start-up, a retraction step of switching from a printing state to an idle state, a repositioning step of switching from the idle state to a feeding state,

the initial positioning step comprises the following steps:

s101: performing quick wire feeding, and stopping the quick wire feeding after detecting that the wire material contacts the workbench;

s102: performing quick wire withdrawing to enable the wire to be separated from the printing platform;

s103: performing slow wire feeding, and stopping the slow wire feeding after detecting that the wire material contacts the workbench again;

the rollback step comprises the following steps:

s201: setting a back-off time and a back-off speed;

s202: within the backspacing time, performing rapid wire unwinding at the backspacing speed;

the repositioning step comprises:

s301: setting wire feeding time and wire feeding speed;

s302: and in the wire feeding time, performing slow wire feeding at the wire feeding speed.

Technical Field

The invention relates to the technical field of additive manufacturing, in particular to multi-laser coaxial wire feeding additive manufacturing equipment and a wire feeding method.

Background

In the laser additive manufacturing or laser metal 3D printing, the core technology is synchronous control of laser energy facula and material conveying, cladding materials are continuously, accurately and uniformly conveyed to a processing position through a material conveying device, the energy facula of laser is enabled to accurately act on the position, the cladding materials are instantly melted to form a molten pool, and a control system controls a laser printing head and a conveying mechanism of the cladding materials to synchronously move, so that the preset printing work is completed.

The existing material conveying modes mainly include a powder conveying mode, a powder laying mode and a wire conveying mode. The inert gas sealed environment is mainly applied to powder spreading equipment. The powder feeding type is difficult to realize accurate control on the powder feeding amount and uniformity, the utilization rate of powder is low in the processing process, and incompletely melted powder can be adhered to the surface of a workpiece to cause the problems of surface quality defects and the like. The wire feeding type can realize uniform and continuous accurate conveying, and has the advantages of high material utilization rate, cleanness, high efficiency and the like. However, the existing control mode can not realize accurate position control, the problems of no melting of materials or accumulation of materials can occur, and continuous operation can not be realized.

Disclosure of Invention

The invention aims to provide multi-laser coaxial wire feeding additive manufacturing equipment and a wire feeding method, which are used for solving the problem of titanium metal 3D printing under the condition of inert gas sealing.

Particularly, the invention provides a multi-laser coaxial wire feeding additive manufacturing device, which mainly comprises:

the inside of the gas seal box is a sealed environment filled with inert gas;

the moving mechanism assembly is positioned in the gas seal box and comprises a wire feeding device, a laser device, a rotating device and three modules; the three modules are respectively a first module capable of moving along the X-axis direction, a second module capable of moving along the Y-axis direction and a third module capable of moving along the Z-axis direction, the workbench is arranged on a platform consisting of the first module and the second module, and the rotating device is arranged on the workbench; the wire feeding device comprises a wire feeding disc and a wire feeder vertical to the workbench, and the wire feeder is fixed on the third module; a plurality of laser heads of laser device along the circumference of sending a ware is arranged, by the laser that the nozzle of laser head jetted out with send the center pin of a ware to have the settlement contained angle, the angle adjustable of setting for the contained angle, the multi-beam laser that the nozzle of a plurality of laser heads jetted out intersects in same facula, the facula is located send on the center pin of a ware.

Preferably, the rotating means is rotatable along the X-axis and/or the Y-axis.

Preferably, the laser head has optical fiber interface and cooling channel, and laser is followed optical fiber interface transmits to the nozzle, cooling channel's water inlet and delivery port all with optical fiber interface is located same end.

Preferably, the laser head is provided with a light spot adjusting knob for adjusting the position of the focusing mirror so as to adjust the size of the light spot.

Preferably, send a ware with the inside of laser head is hollow protection cavity, send a ware with the laser head is equallyd divide and is provided with respectively be used for to protection cavity lets in inert gas's air inlet unit.

Preferably, a wire drawing mechanism is arranged in the wire feeder, wires are fed from the wire feeding disc to the wire drawing mechanism through a guide wheel, and the wire drawing mechanism comprises a driving device, a driven pressing wheel, a sensor, a wire feeding correction pipe and a wire discharging correction pipe.

Preferably, the method further comprises the following steps:

the transition cabin is a hollow cabin body, a workpiece is placed in the hollow cabin body, the hollow cabin body is vacuumized through a vacuum pump, protective gas is filled, and the inner cabin door is opened to realize a feeding process;

and the auxiliary box body is internally provided with a gas circulation and regeneration system and a laser, the gas circulation and regeneration system is connected with the gas seal box through a pipeline, and the laser is connected with the optical fiber interface through an optical fiber.

Preferably, the laser heads are low-power laser equipment, and the number of the laser heads is at least two.

Preferably, the laser head is rotatably connected with the wire feeder through a screw rod, and the screw rod is relatively vertical to a central shaft of the wire feeder so as to adjust the angle of the set included angle.

According to another aspect of the invention, the invention also discloses an additive manufacturing wire feeding method of the control equipment, which comprises an initial positioning step of initial starting, a returning step when the printing state is switched to the idle state, a repositioning step when the idle state is switched to the feeding state,

the initial positioning step comprises the following steps:

s101: performing quick wire feeding, and stopping the quick wire feeding after detecting that the wire material contacts the workbench;

s102: performing quick wire withdrawing to enable the wire to be separated from the printing platform;

s103: performing slow wire feeding, and stopping the slow wire feeding after detecting that the wire material contacts the workbench again;

the rollback step comprises the following steps:

s201: setting a back-off time and a back-off speed;

s202: within the backspacing time, performing rapid wire unwinding at the backspacing speed;

the repositioning step comprises:

s301: setting wire feeding time and wire feeding speed;

s302: and in the wire feeding time, performing slow wire feeding at the wire feeding speed.

Preferably, in the initial positioning step, the speed of performing the fast wire feeding in S101 is 10m/min, the speed of performing the fast wire withdrawing in S102 is 5m/min, and the speed of performing the slow wire feeding in S103 is 1 m/min.

According to the multi-laser coaxial wire feeding additive manufacturing equipment, due to the layout structure of the movement mechanism assembly, particularly the combination mode of the wire feeder and the laser head, the symmetrical layout, the structure and the occupied space are stable, so that the optical fiber moving range is small, the stability of laser can be ensured, and the high precision can be ensured.

Furthermore, the multi-laser coaxial wire feeding additive manufacturing equipment adopts multi-path optical path integration, the concentricity of the multi-path optical paths is realized through the optical path angle adjusting knob, and each laser head is provided with a button to adjust the size of a light spot, so that the light spots can be balanced and the quality is stable; the space is balanced, so that the problem of high heat dissipation of the high-power laser head can be solved; the positions before and after printing can be adjusted, the temperature difference is adjusted, and the problem of stress concentration cracks caused by overlarge temperature difference in the material adding process is solved.

The above and other objects, advantages and features of the present invention will become more apparent to those skilled in the art from the following detailed description of specific embodiments thereof, taken in conjunction with the accompanying drawings.

Drawings

Some specific embodiments of the invention will be described in detail hereinafter, by way of illustration and not limitation, with reference to the accompanying drawings. The same reference numbers in the drawings identify the same or similar elements or components. Those skilled in the art will appreciate that the drawings are not necessarily drawn to scale. In the drawings:

FIG. 1 is an overall schematic view of a multi-laser coaxial wire feed additive manufacturing apparatus of the present invention;

FIG. 2 is a schematic view of a motion mechanism assembly in the multi-laser coaxial wire feed additive manufacturing apparatus of the present invention;

FIG. 3 is a schematic view of the laser head and wire feeder shown in FIG. 2;

FIG. 4 is a schematic view of the simple connections of the wire feed spool, wire feeder, and wire drawing mechanism;

FIG. 5 is a flow chart of a wire initialization positioning process in an additive manufacturing wire feed method;

FIG. 6 is a flow chart of wire backtracking in an additive manufacturing wire feed method;

FIG. 7 is a flow chart of wire repositioning in an additive manufacturing wire feed method;

the meanings indicated by the reference symbols in the figures are as follows:

1-gas seal box; 2-auxiliary box body; 3-a transition cabin; 4-an electric box; 5-a control panel; 6-a water cooling machine; 7-a vacuum pump; 8-a wire feeding disc; 9-a wire feeder; 10-a laser head; 11-a module; 12-a work bench; 13-a scaffold; 14-a rotating device; 15-fixing the installation position; 16-a filament inlet; 17-optical fiber interface, 18-water inlet; 19-water outlet; 20-a light spot adjusting knob; 21-an air intake device; 22-light path angle adjusting knob; 23-a nozzle; 24-a guide wheel; 25-a wire feeding pipe; 26-straightening tube.

Detailed Description

The invention mainly solves the problem of performing titanium metal 3D printing under the condition of inert gas sealing. The specific structure is that a wire feeding structure is adopted, materials are introduced into a molten pool generated by a laser beam to be melted, and then a printing component with a complex shape is formed under the action of a moving mechanism.

Fig. 1 is an overall schematic diagram of an additive manufacturing apparatus. The inside of the gas seal box 1 is an inert gas sealed environment. The gas seal box 1 is internally provided with a motion mechanism assembly, and the additive manufacturing process of special alloy can be carried out. The front upper side of the gas seal box is provided with an openable glass window structure, so that the internal structure is convenient to observe and adjust; preceding downside is two glove openings, at the gas seal in-process, makes things convenient for the staff to carry out interior operation. The auxiliary case 2 is located below the gas tight case 1. The auxiliary box 2 is internally provided with a gas circulation regeneration system, a laser and the like. The gas circulation and regeneration system is connected with the gas seal box 1 through a pipeline and is used for removing oxygen and water and ensuring the closed environment of inert gas. The laser is connected with a laser head 10 in the motion mechanism assembly through an optical fiber. The transition compartment 3 is located on the right side of the apparatus. The transition cabin 3 is a hollow cabin body, a workpiece is placed in the transition cabin, then the transition cabin is vacuumized through the vacuum pump 7 and is filled with protective gas, and then the inner cabin door is opened to realize the feeding process. The electronic box 4 is positioned at the lower right side of the equipment and is surrounded by a metal plate, so that the attractiveness is guaranteed. The control panel 5 is positioned at the upper right side of the equipment, so that the operation and observation are convenient. And the water cooling machine 6 is used for double-temperature control to ensure the cooling of the laser and the laser head 10.

Fig. 2 is a schematic view of the kinematic mechanism assembly, located inside the gas-tight box 1. The moving mechanism assembly comprises a wire feeder, a laser device, a rotating device 14 and three modules 11. The module 11 is arranged on a support 13. In this embodiment, the bracket 13 is L-shaped, a second module movable along the Y-axis is connected to the horizontal frame, a third module movable along the Z-axis is connected to the vertical frame, and a first module movable along the X-axis is connected to the upper side of the second module. The table 12 is arranged on a platform consisting of said first die set and said second die. That is, the table 12 has two degrees of freedom, moving in the X-axis direction and the Y-axis direction. A rotating device 14 is provided on the table 12. The rotating means 14 shown in fig. 2 is able to rotate around the X-axis. In other embodiments, the rotating device 14 may also be configured to rotate about the Y-axis; or the rotating means 14 is arranged to be rotatable about both the X-axis and the Y-axis.

Fig. 3 is a schematic view of the laser head 10 and the wire feeder 9. Fig. 4 is a schematic diagram showing the simple connection of the wire feeding disc 8, the wire feeder 9, and the wire drawing mechanism. With reference to fig. 2, 3 and 4, the wire feeder comprises a wire feed drum 8 and a wire feeder 9 perpendicular to said table 12. The wire feeder 9 is fixed to the third module through a fixing mounting position and can vertically move up and down along the Z axis. A wire drawing mechanism is arranged in the wire feeder 9, and the wire reaches the wire drawing mechanism from the wire feeding disc 8 through the guide wheel 24. Between the guide wheel and the wire feeder 9, a wire feed tube 25 is provided for guiding the path of the wire. The inlet 16 and outlet of the wire feeder 8 are provided with straightening tubes 26. The inside of the wire feeder 9 is a hollow protection cavity. The wire feeder 9 is provided with an air inlet device 21 for introducing inert gas into the protective cavity.

The wire drawing mechanism comprises a driving device, a driven pinch roller, a sensor, a wire feeding correction pipe and a wire discharging correction pipe. The driving device is connected with a speed reducer by a servo motor or a stepping motor to be used as power output to drive the driving wheel to rotate. The radius range of the wire is 0.6-1.05mm, and the wire feeding speed is 0-10 m/min. The wire drawing mechanism is closer to the wire outlet nozzle, so that the wire feeding precision is higher, the stability is good, and the required output torque is larger.

A plurality of laser heads 10 of the laser device are arranged along the circumference of the wire feeder 9. The laser emitted from the nozzle of the laser head 10 has a set angle with the central axis of the wire feeder 9. The laser head 10 is rotatably connected to the wire feeder 9 by means of a screw. The screw is relatively perpendicular to the central axis of the wire feeder 9. When the light path angle adjusting knob 22 beside the screw is adjusted, the laser head 10 can rotate around the screw, thereby controlling the nozzle 23 to be close to or far away from the central axis of the wire feeder 9 to adjust the angle of the set included angle. The laser welding device is provided with a plurality of laser heads 10, wherein a plurality of laser beams emitted by nozzles of the laser heads are converged at the same light spot, and the light spot is positioned on a central shaft of a wire feeder, so that a molten pool is formed. The laser head 10 also has a spot adjustment knob 20 for adjusting the position of the internal focusing mirror to adjust the size of the spot.

In the present embodiment, the number of the laser heads 10 is three, and they are arranged at uniform intervals in the circumferential direction of the wire feeder 9. Each laser head 10 is a low power laser device. The problem of overhigh price of a high-power laser can be solved by adopting a low-power laser device. The light path angle adjusting knob is used for realizing the concentricity of the multiple light paths, and each laser head is provided with a button for adjusting the size of a light spot. Three paths of laser are mixed for use, so that light spots can be balanced, and the quality is stable; the space is balanced, so that the problem of high heat dissipation of the high-power laser head can be solved; the laser spot position is adjustable, and adjustable position before printing adjusts the difference in temperature, solves the vibration material disk material feeding in-process, because the too big stress concentration crackle problem that causes of the temperature difference in temperature.

The laser head 10 also has an optical fiber interface 17 and cooling channels. The laser light is transmitted from the optical fiber interface 17 to the nozzle 23. Wherein, the water inlet 18 and the water outlet 19 of the cooling channel are both positioned at the same end with the optical fiber interface 17. The inside of each laser head 10 is a hollow protection cavity. The laser head 10 is provided with an air inlet means 21 for introducing inert gas into the protective chamber, thereby protecting the stability of the internal environment.

The layout structure of the motion mechanism assembly, particularly the combination mode of the wire feeder 8 and the laser head 10, has symmetrical layout, stable structure and small occupied space, thereby ensuring that the optical fiber has small moving range, ensuring the stability of laser and ensuring high precision.

According to another aspect of the present invention, as shown in the flowcharts of fig. 5, 6 and 7, the present invention further discloses an additive manufacturing wire feeding method for controlling equipment, which includes an initial positioning step of first starting, a retraction step when switching from a printing state to an idle state, and a repositioning step when switching from the idle state to a feeding state.

FIG. 5 is a flow chart of wire initialization positioning in an additive manufacturing wire feeding method. The initial positioning step comprises the following steps:

s101: performing quick wire feeding, and stopping the quick wire feeding after detecting that the wire material contacts the workbench;

s102: performing quick wire withdrawing to enable the wire to be separated from the printing platform;

s103: and performing slow wire feeding, and stopping the slow wire feeding after detecting that the wire material contacts the workbench again.

Firstly, starting wire positioning initialization, and executing rapid wire feeding until a sensor detects that a wire contacts a printing platform. And then the wire is rapidly withdrawn, so that the wire is separated from the printing platform. And finally, carrying out slow wire feeding until the wire material contacts the printing platform again to finish positioning initialization. The initialization positioning step has the function of time overtime alarm to prevent overtime operation. In the initial positioning step of the embodiment, the speed of performing the fast wire feeding in S101 is 10m/min, the speed of performing the fast wire withdrawing in S102 is 5m/min, and the speed of performing the slow wire feeding in S103 is 1 m/min. Taking a conveying distance of 150mm as an example, the positioning time is 1.2s, and the repeated positioning precision is 0.2 mm.

FIG. 6 is a flow chart of wire backtracking in an additive manufacturing wire feed method. The rollback step comprises the following steps:

s201: setting a back-off time and a back-off speed;

s202: and in the backspacing time, performing rapid wire unwinding at the backspacing speed.

Each time the printer is switched from the printing state to the idle state, the printer needs to execute the wire withdrawing action and stop the laser operation. The specific retraction distance and speed can be set according to actual needs. In the retracting step of this embodiment, the fast wire-retracting speed is set to 5 m/min. The equipment sets the rollback time to be 0.2s, the rollback speed to be 5m/min and the rollback distance to be about 10 mm.

FIG. 7 is a flow chart of wire repositioning in an additive manufacturing wire feed process. The repositioning step comprises:

s301: setting wire feeding time and wire feeding speed;

s302: and in the wire feeding time, performing slow wire feeding at the wire feeding speed.

When switching from the idle state to the feed state, the wire needs to be positioned again. In the repositioning step of this embodiment, the wire feeding distance is 10mm, the wire feeding speed is 2m/min, and the time is about 0.3 s.

In conclusion, the invention provides multi-laser coaxial wire feeding additive manufacturing equipment and a wire feeding method, which are used for performing titanium metal 3D printing under the condition of inert gas sealing, ensuring that metal wires can be accurately conveyed to a processing position, and ensuring that laser additive manufacturing work is completed with high efficiency, high precision and high stability.

Thus, it should be appreciated by those skilled in the art that while a number of exemplary embodiments of the invention have been illustrated and described in detail herein, many other variations or modifications consistent with the principles of the invention may be directly determined or derived from the disclosure of the present invention without departing from the spirit and scope of the invention. Accordingly, the scope of the invention should be understood and interpreted to cover all such other variations or modifications.