CN206455176U - A kind of dust feeder of synchronous powdering formula metal laser 3D printing - Google Patents

Abstract

A synchronous powder-spreading metal laser 3D printing powder feeding device, including a powder storage bin (1), a powder feeding bin (2), a powder feeding belt (3), a powder spreading head (4), a main transmission gear (5), a slave Transmission gear (6), driving motor (7), beam (18), cladding head (19) and shell (11). The powder feeding bin of the utility model is fixed on the cladding head through rolling bearings to rotate freely, and a transmission gear is installed on the upper part of the powder feeding bin, which meshes with another transmission gear to form a transmission gear pair, and the predetermined action is realized under the drive of the motor; the powder storage bin is stationary, However, it keeps sliding relative to the powder feeding bin; the powder enters the powder feeding belt from the bottom outlet of the powder feeding bin and is sent to the powder spreading head driven by the driving wheel, and the powder is evenly spread on the substrate under the action of gravity to form a powder layer; the powder spreading head It is fixed on the cladding head together with the shell; the powder feeding chamber and the cladding head are coordinated to move through the program setting to ensure that the powder layer is always in front of the laser spot; the inside of the powder spreading head is cooled by circulating water.

Description

A synchronous powder feeding device for metal laser 3D printing

technical field

The utility model relates to a synchronous powder-spreading metal laser 3D printing powder feeding device and method, belonging to the technical field of laser 3D printing.

Background technique

At present, there are two main methods of powder supply in the process of metal laser cladding or laser 3D printing, namely powder spreading and synchronous powder feeding. The powder-spreading powder supply system spreads a thin layer of metal powder on the entire area of the cavity by mechanical means, and the laser performs "selective melting" in the designated area, and most of the powder is not used; while the synchronous powder feeding type powder The supply system sends the metal powder to the laser spot through gas or gravity, and melts while feeding the powder. Most of the powder is blown away by the gas or bounced away from the matrix, and the utilization rate of the powder is very low. More importantly, under the impact of the carrier gas and the shielding gas, the liquid level of the molten pool will be disturbed obviously, which will affect the microstructure of the cladding layer. In some exploratory studies of laser cladding or laser metal 3D printing, metal powder is very expensive and rare, and needs to be used efficiently, and the printing chamber is protected by inert gas, so the effect of carrier gas and shielding gas is weakened so that it can be ignored .

Contents of the invention

The purpose of this utility model is to improve the accuracy and efficiency of powder supply, eliminate the impact and disturbance of the carrier gas and protective gas on the molten pool, improve the accuracy and efficiency of metal laser 3D printing, and reduce powder waste. The utility model proposes a Synchronous powder feeding device for metal laser 3D printing.

The technical solution for realizing the utility model is as follows: a synchronous powder-spreading metal laser 3D printing powder feeding device includes a powder storage bin, a powder feeding bin, a powder feeding belt, a powder spreading head, a main transmission gear, a slave transmission gear, a drive motor, and a beam , cladding head and shell.

The powder storage bin 1 is fixed on the cladding head 19 and is provided with a powder inlet 10, which is slidingly matched with the powder feeding bin 2; the powder feeding bin 2 is fixedly installed with the slave transmission gear 6, and is fixed on the On the cladding head 19; the transmission gear 6 is provided with a powder delivery port 22 connected to the powder storage bin 1, and the powder 9 in the powder storage bin 1 enters the powder storage bin 1 through the powder inlet 10 and then enters the powder delivery bin 2 through the powder delivery port 22 to realize Continuous delivery of powder 9; the powder outlet 23 is set at the bottom of the powder delivery chamber 2, and the powder 9 is taken away by the passing powder delivery belt 3 through the powder outlet 23 and transported to the powder spreading head 4, and then evenly distributed under the action of gravity Spread on the substrate 17 to form a powder layer 21 with a width of 1-10mm; the slave transmission gear 6 and the main transmission gear 5 mesh with each other, and the main transmission gear 5 drives the slave transmission gear 6 under the drive of the motor 7 to drive the powder feeding The bin 2 and the powder feeding belt 3 rotate around the cladding head 19 together, and make coordinated movements with the cladding head 19 through program setting to ensure that the powder layer 21 is always in front of the laser spot 20 in the forward direction; the motor 7 is installed on the On the beam 18; the powder spreading head 4 is fixed on the cladding head 19 through the shell 11, and its interior is cooled by circulating cooling water. Powder head 4; the laser spot 20 is irradiated on the powder layer 21 to form a cladding layer, and a metal laser 3D printing sample is obtained after layer-by-layer printing.

A large number of powder feeding hoppers 24 are uniformly distributed on the powder feeding belt 3, and are used for powder transportation, and the width thereof is 1-20mm; It can be an inverted conical truncated pyramid, an inverted quadrangular pyramid truncated, or a bucket; the moving speed of the powder feeding belt 3 is 0~1000mm/min; driven by the driving wheel 12, the powder feeding belt 3 can realize continuous powder feeding, Change the powder feeding speed, pause the action; the relative position of the driving wheel 12 and the two driven wheels is adjustable, so as to realize the adjustment of the downhill angle of the powder feeding belt 3, and the downhill angle adjustment range is 30°~60°.

The powder spreading head 4 is a hollow conical ring structure, on which a water inlet 13 and a water outlet 14 are arranged; the angle between the busbar of the inner conical hole and the axis is 30°~60°, so as to adjust the uniformity of powder spreading.

The main transmission gear 5 has a diameter of 10-50mm, and the diameter ratio of the main transmission gear 5 and the secondary transmission gear 6 is 1:1-1:5.

The powder feeding bin 2 and the slave transmission gear 6 are fixed together, and the slave transmission gear 6 meshes with the main transmission gear 5 and is driven by the motor 7 to move in coordination with the cladding head 19, that is, the cladding head 19 is on the motion track Rotate the angle θ, the powder feeding bin 2 rotates around the cladding head 19 correspondingly by the angle θ to ensure that the powder layer 21 is always evenly spread in front of the laser spot 20; the rotation speed of the powder feeding bin 2 is 0~100 r/min.

The inner ring of the rolling bearing 8 is fixed on the cladding head 19, and the outer ring closely cooperates with the powder feeding bin 2 to ensure that the powder feeding bin 2 can move freely.

The powder spreading head 4 is fixed on the cladding head 19 through the casing 11 , and the casing 11 is provided with a window 16 for the main transmission gear 5 to enter and mesh with the secondary transmission gear 6 .

The powder storage bin 1, the powder feeding bin 2, and the shell 11 are all made of transparent materials for easy observation.

Compared with the prior art, the beneficial effects of the utility model are:

The utility model adopts the method of synchronous powder spreading, and the metal powder spreads the powder on the substrate smoothly and evenly under the action of gravity through the powder feeding bin, the powder feeding belt and the powder spreading head, which reduces the flow speed of the powder and reduces the The impact on the surface of the substrate reduces the possibility of powder bouncing off the substrate, thereby greatly improving powder utilization. The driving mechanism adopted by the utility model can coordinate the movement of the powder feeding bin and the cladding head through program setting to ensure that the powder layer is always in front of the laser spot; the powder feeding belt of the utility model can be controlled under the guidance of the driver program. Complete continuous powder feeding, changing powder feeding speed, etc., and also can stop powder feeding in conjunction with the rotation of the powder feeding bin (for example, when the cladding head turns 180° sharply, the powder feeding bin rotates 180° around the cladding head, during which the powder feeding With pause powder feeding) to reduce the waste of powder. The distance between the powder spreading head and the base plate and the relative position between the light outlet of the cladding head and the powder spreading head adopted by the utility model can be adjusted, so as to ensure that the laser spot is irradiated on the metal powder in a focused state. The powder feeding belt of the utility model is composed of a large number of powder feeding hoppers, through the discretization of the continuous powder flow, the controllable powder feeding of the metal powder is completed (changing the powder feeding rate, the width of the powder layer, the thickness of the powder layer, etc.), and the powder utilization rate.

The utility model is suitable for the 3D printing process with a protective atmosphere chamber. The carrier gas and protective gas are not involved in the powder delivery and spreading process, thereby eliminating the impact and disturbance of the gas and powder on the molten pool, and improving the internal structure of the printing layer. Consistency and directionality.

Description of drawings

Fig. 1 is a schematic diagram of the overall structure of the utility model;

Figure 2 is a schematic diagram of the plane structure of the powder feeding belt;

Fig. 3 is a schematic diagram of the cross-sectional structure of the powder feeding belt;

Figure 4 is a schematic diagram of the coordinated movement of the powder feeding bin and the cladding head;

Among them: 1 is the powder storage bin, 2 is the powder feeding bin, 3 is the powder feeding belt, 4 is the powder spreading head, 5 is the main transmission gear, 6 is the slave transmission gear, 7 is the driving motor, 8 is the rolling bearing, 9 is the metal powder, 10 is the powder inlet, 11 is the shell, 12 is the driving wheel, 13 is the water inlet, 14 is the powder outlet, 15 is the cooling water, 16 is the window, 17 is the base plate, 18 is the beam, 19 is the cladding head, 20 21 is a powder spreading layer, 22 is a powder feeding port, 23 is a powder outlet, and 24 is a powder feeding hopper.

detailed description

Below in conjunction with accompanying drawing, the utility model is described in further detail:

The structure of a synchronous powder-spreading metal laser 3D printing powder feeding device in this embodiment is shown in Figure 1, including a powder storage bin 1, a powder feeding bin 2, a powder feeding belt 3, a powder spreading head 4, a main transmission gear 5, a slave transmission Gear 6, drive motor 7, beam 18, cladding head 19 and shell 11.

In this embodiment, the metal powder 9 is Inconel 625 superalloy powder, which is spherical and has a particle size of 40-100 μm. A sample with a size of 50mm×50mm×50mm is prepared by laser 3D printing. The scanning path adopts an "S" shape, the laser spot diameter is 3mm, the overlap rate is 50%, the scanning speed is 300mm/min, and the laser power is 1000W.

As shown in Figure 1, the metal powder 9 is loaded into the powder storage bin 1 from the powder inlet 10, and the powder storage bin 1 is fixed on the cladding head 19; the powder 9 flows into the powder feeding bin 2 through the powder delivery port 22 until it is filled; at this time, the powder feeding The belt 3 is in a static state, and the powder 9 will not flow out from the powder outlet; adjust the distance between the powder spreading head 4 and the substrate 17 to 4mm, and the spot diameter to 3mm; start the powder feeding belt 3, and transport the powder 9 to the powder spreading head 4 , under the action of gravity, the powder 9 is evenly and smoothly spread on the substrate 17 along the inner wall of the powder spreading head 4 to form a powder layer 21. The width of the powder layer 21 is about 4 mm. In this embodiment, the powder feeding speed is 30 mm/min. The width of the belt 3 is 8 mm, and there are 4 powder feeding hoppers 24 distributed in the width direction. The structure of the powder feeding hopper can be an inverted conical truncated cone or an inverted quadrangular pyramidal truss. In this embodiment, an inverted quadrangular pyramidal truss is used, as shown in Figure 2 and Figure 3 Show. Turning on the power of the laser produces a laser spot 20, which is irradiated on the powder layer 21 and melted to form a cladding layer.

According to the program setting, the short side of the scanning path does not emit light, so as to improve the cladding accuracy at right-angle turns; by cooperating with the movement track of the cladding head 19, that is, when the cladding head 19 rotates clockwise through 180° for scanning in the opposite direction, the driving The motor 7 drives the transmission gear 5 to rotate 180° counterclockwise and drives the transmission gear 6 to rotate 180° clockwise, so that the powder feeding bin 2 rotates 180° clockwise around the cladding head 19 relative to the original direction to ensure the powder layer 21 is always located directly in front of the laser spot 20; in accordance with the movement track of the powder feeding bin 2, the driving wheel 12 of the powder feeding belt 3 stops rotating during the rotation of the powder feeding bin 2, so that the powder 9 stays in the powder feeding hopper 24, Reduce powder waste. In this embodiment, the coordinated movement of the powder feeding bin and the cladding head is shown in Figure 4 .

In this embodiment, the rotation speed of the driving motor 7 is 30 r/min, the diameter of the transmission gear 5 is 20 mm, and the diameter ratio of the transmission gear 5 and the transmission gear 6 is 1:2.

The powder spreading head 4 is fixed on the cladding head 19 through the casing 11, the powder storage bin 1, the powder spreading head 4, and the casing 11 are fixed during operation, and the transmission gear 6, the powder feeding bin 2, and the powder feeding belt 3 are wound around the cladding head 19 Rotate, the powder feeding belt 3 is driven by the driving wheel 12 to make a circular motion; the material of the powder spreading head 4 can be copper alloy to enhance the cooling effect, the interior is hollow, and the circulating cooling water 15 enters from the water inlet 13 and flows out from the water outlet 14. This implementation In the example, the flow rate of cooling water is 20L/min.

Claims (7)

1. A powder feeding device for synchronous powder spreading type metal laser 3D printing, characterized in that the device includes a powder storage bin, a powder feeding bin, a powder feeding belt, a powder spreading head, a main transmission gear, a slave transmission gear, a drive motor, Beam, cladding head and shell; the powder storage bin is fixed on the cladding head and is provided with a powder inlet, which is slidingly matched with the powder feeding bin; the powder feeding bin is fixedly installed with the slave transmission gear and fixed by rolling bearings On the cladding head; the transmission gear is provided with a powder feeding port connected to the powder storage bin, the powder in the powder storage bin enters the powder storage bin through the powder inlet and then enters the powder feeding bin through the powder feeding port to realize continuous delivery of powder; A powder outlet is set at the bottom of the powder bin, and the powder is taken away by the passing powder feeding belt through the powder outlet and transported to the powder spreading head, and then spread evenly on the substrate under the action of gravity to form a powder layer with a width of 1~10mm; The slave transmission gear and the main transmission gear mesh with each other, and the main transmission gear drives the slave transmission gear under the drive of the motor to drive the powder feeding bin and the powder feeding belt to rotate around the cladding head together, and coordinate movement with the cladding head through program setting , so as to ensure that the powder layer is always in front of the advancing direction of the laser spot; the motor is installed on the beam; The nozzle enters the powder spreading head, and flows out of the powder spreading head through the water outlet; the laser spot is irradiated on the powder layer to form a cladding layer, and the metal laser 3D printing sample is obtained after layer-by-layer printing. 2. A synchronous powder-spreading metal laser 3D printing powder feeding device according to claim 1, characterized in that a large number of powder feeding hoppers are evenly distributed on the powder feeding belt to transport powder, and its width 1~20mm; the powder feeding hoppers are distributed 1~10 horizontally on the powder feeding belt, and its structure can be an inverted conical truncated pyramid, an inverted quadrangular pyramid, or a bucket; the moving speed of the powder feeding belt is 0~1000mm/ min; driven by the driving wheel, the powder feeding belt can realize continuous powder feeding, change the powder feeding speed, and pause according to actual needs; the relative position of the driving wheel and the two driven wheels can be adjusted, so that the powder feeding belt can go downhill Angle adjustment, downhill angle adjustment range 30°~60°. 3. A synchronous powder-spreading metal laser 3D printing powder feeding device according to claim 1, characterized in that, the powder-spreading head is a hollow conical ring structure, and a water inlet and a water outlet are arranged on it; The angle between the generatrix of the conical hole and the axis is 30°~60°, so as to adjust the uniformity of powder spreading. 4. The powder feeding device of a kind of synchronous powder spreading type metal laser 3D printing according to claim 1, is characterized in that, the diameter of the main transmission gear is 10 ~ 50mm, and the diameter ratio of the main transmission gear and the slave transmission gear is 1: 1~1:5. 5. A synchronous powder-spreading metal laser 3D printing powder feeding device according to claim 1, characterized in that the powder feeding bin is fixed with the slave transmission gear, and the slave transmission gear is connected with the main transmission gear. Mesh and move in coordination with the cladding head under the drive of the motor, that is, the cladding head rotates at an angle of θ on the motion track, and the powder feeding bin rotates at an angle of θ around the cladding head to ensure that the powder layer is always evenly spread in front of the laser spot ; The rotation speed of the powder feeding bin is 0~100 r/min. 6. A synchronous powder-spreading metal laser 3D printing powder feeding device according to claim 1, characterized in that the inner ring of the rolling bearing is fixed on the cladding head, and the outer ring is connected to the powder feeding chamber Tight fit, and ensure that the powder feeding chamber can move freely. 7. The powder feeding device of a synchronous powder-spreading type metal laser 3D printing according to claim 1, wherein the powder-spreading head is fixed on the cladding head through a casing, and a window is provided on the casing for feeding The master drive gear enters into mesh with the slave drive gear.