Powder roller device for metering discharged powder and 3D printer

Abstract

The utility model discloses a powder rolling device for metering discharged powder and a 3D printer in the field of powder discharging of 3D printers, the powder rolling device for metering discharged powder comprises a machine shell, the upper end and the lower end of the machine shell are respectively provided with a powder inlet channel and a powder outlet channel, and a metering powder roller is rotatably arranged in the machine shell. The metering powder roller blocks a passage between the powder inlet channel and the powder outlet channel; the metering powder roller is connected with a driving mechanism used for driving the metering powder roller to rotate around the central axis of the metering powder roller, and a plurality of metering grooves with the same inner capacity are evenly formed in the metering powder roller in the circumferential direction around the central axis of the metering powder roller. According to the 3D printing powder discharging device, powder is not prone to being clamped in the powder discharging process of 3D printing, powder is saved, and powder is discharged efficiently.

Description

TECHNICAL FIELD

[0001] The utility model relates to 3D printer powder out's technical field especially is involved in a kind of powder rolling device and 3D printer. BACKGROUND

[0002] 3D metal printer is a kind of scientific instrument for physics, engineering and technical science basic disciplines, mechanical engineering field, utilizes laser melting technology to melt metal powder, forms functional entity component, is full digital rapid prototyping manufacturing work, directly according to the interface data of each layer of three-dimensional CAD production full high-density metal parts, melting metal layer thickness is from 20 microns to 100 microns.Metal rapid prototyping, 3D printer when manufacturing parts, need first quantitative feeding of metal powder to equipment powder laying mechanism, then powder is laid on forming base plate, and metal powder layer is distributed uniformly using scraper, then each metal layer is melted in strictly controlled air environment and layer by layer, finally get entity component.

[0003] At present, push plate type powder discharge mechanism is often used as the powder discharge mechanism of 3D printer, and the push plate type powder discharge mechanism drives the reciprocating movement of the discharge plate through the motor and screw rod, the discharge plate is provided with a discharge port, the powder flows into the discharge port, the discharge plate is driven to extend to the powder discharge position through the motor and screw rod, and the powder in the discharge port flows out to complete single discharging.

[0004] Since the push plate type powder discharge mechanism drives the reciprocating movement of the discharge plate through the motor and screw rod, part of the dust will enter the screw rod part during the reciprocating powder discharge process, causing the mechanism to be stuck; during the reciprocating movement, part of the powder is diffused to the powder discharge port in the opposite direction through the discharge plate, causing waste of powder; and the discharge plate needs to reciprocate once every time powder is discharged, so the powder discharge efficiency is poor. UTILITY MODEL CONTENTS

[0005] The utility model provides a kind of powder rolling device and 3D printer for metering powder discharge, which can not jam powder, save powder and discharge powder efficiently.

[0006] To solve the above technical problems, in the first aspect, the powder rolling device for metering powder discharge provided by the utility model adopts the following technical scheme:

[0007] A powder rolling device for metering powder discharge includes a housing, an upper end and a lower end of the housing are respectively provided with an inlet channel and an outlet channel, a metering roller is rotatably arranged inside the housing, and the metering roller blocks the passage between the inlet channel and the outlet channel; the metering roller is connected with a driving mechanism for driving the metering roller to rotate around the central axis, and the metering roller is circumferentially provided with a plurality of metering grooves with the same content around the central axis.

[0008] By adopting the technical scheme, when the 3D printer discharges powder, the metal powder first enters the shell through the powder inlet channel. Since the metering roller blocks the passage between the powder inlet channel and the powder outlet channel, the metal powder can only enter the metering groove facing the powder inlet channel. Then, the metering roller is driven to rotate by the driving mechanism, so that the metering groove containing the metal powder rotates towards the powder outlet channel, so that the metal powder in the metering groove falls into the powder outlet channel to complete the powder discharge. Since the metering roller is circumferentially provided with a plurality of metering grooves, the metering roller can transport the metal powder in the powder inlet channel to the powder outlet channel for powder discharge by single direction rotation. The powder discharging efficiency is high, and since the movement direction, powder jamming is less likely to occur, and powder discharge is more smooth. Moreover, since the capacities of the plurality of metering grooves are the same, the powder discharge amount can be accurately controlled.

[0009] Optionally, a material guiding block is fixedly arranged inside the shell, and the material guiding block is provided with a material guiding opening. The upper end of the material guiding opening is connected to the edge of the powder inlet channel, and the lower end is attached to the outer circumferential surface of the upper half of the metering roller.

[0010] By adopting the technical scheme, the path of the metal powder from the powder inlet channel to the metering groove is guided by the material guiding block to reduce the possibility of the metal powder being scattered in the shell and entering the powder outlet channel between the outer circumferential surface of the metering roller and the inner wall of the shell, thereby improving the accuracy of controlling the powder discharge amount. The possibility of the metal powder being accumulated and stuck between the outer circumferential surface of the metering roller and the inner wall of the shell is reduced, thereby reducing the possibility of powder jamming.

[0011] Optionally, the material guiding block is made of rubber.

[0012] By adopting the technical scheme, the material guiding block made of rubber can be more closely attached to the metering roller, and the interference with the rotation of the metering roller is less, thereby further reducing the possibility of the metal powder being scattered through the gap between the material guiding block and the outer circumferential surface of the metering roller, thereby reducing the possibility of powder jamming and powder leakage.

[0013] Optionally, the shell comprises a first shell and a second shell which are detachably connected. The powder inlet channel is arranged in the first shell, and the metering roller and the powder outlet channel are arranged in the second shell. The inner wall of the second shell is provided with a positioning groove, the material guiding block is placed in the positioning groove, and the first shell abuts against the material guiding block.

[0014] By adopting the technical scheme, the shell is divided into a first shell and a second shell which are detachably connected, and the material guiding block is clamped by the first shell and the second shell. Therefore, the material guiding block can be easily replaced after long-term use and wear. At the same time, the material guiding block can also block and plug the gap between the first shell and the second shell, thereby reducing the possibility of the metal powder escaping from the gap between the first shell and the second shell, and improving the sealing performance of the shell.

[0015] Optionally, the opening edge of the powder inlet channel is provided with a clamping part which is inserted into the material guide opening and buckled on the opening edge of the material guide opening.

[0016] By adopting the above technical scheme, the clamping part can position the position of the guide block relative to the powder inlet channel, and can also connect the powder inlet channel and the material guide opening, so that the metal powder can enter the material guide opening more smoothly from the powder inlet channel

[0017] Optionally, the inner wall of the powder inlet channel is fixedly provided with a plurality of partition plates, the plurality of partition plates are arranged in a spaced manner along the long side direction of the opening surface of the powder inlet channel, and the metering groove and the discharge channel are provided with a partition part corresponding to the position of the plurality of partition plates.

[0018] By adopting the above technical scheme, due to the need for powder outlet position during 3D printing, the opening surface of the powder inlet channel and the powder outlet channel is usually rectangular and the long side is relatively long. By arranging and supporting the powder inlet channel along the long side direction through a plurality of partition plates, the possibility of deformation of the powder inlet channel due to excessive span can be reduced. Similarly, the partition part of the metering groove and the discharge channel can reduce the possibility of deformation of the metering groove and the discharge channel due to excessive span.

[0019] Optionally, the outer circumferential surface of both ends of the metering roller is provided with a powder collecting groove, the powder collecting groove is arranged around the central axis of the metering roller, and the two powder collecting grooves are located on both sides of all the metering grooves.

[0020] By adopting the above technical scheme, during the process of metal powder entering the metering groove from the powder inlet channel, the metal powder is prone to fall on the outer circumferential surface of both ends of the metering roller. When the metal powder continues to move and disperse towards both ends of the metering roller, the powder collecting groove can collect the metal powder moving towards both ends of the metering roller and hinder its continuous movement, so as to avoid the metal powder moving to the connection position of the metering roller and the driving mechanism, and affecting the driving process of the driving mechanism on the metering roller. It can also avoid the metal powder from escaping to other parts of the machine shell or through the rotating part of the metering roller and the machine shell to escape from the machine shell, thereby causing waste of metal powder and environmental pollution.

[0021] Optionally, the metering roller is provided with two bosses around the central axis, and the two bosses are located on the side away from the two powder collecting grooves.

[0022] By adopting the above technical scheme, the two bosses can further intercept the metal powder which is not intercepted and collected by the powder collecting groove, so as to further hinder the metal powder from moving and dispersing towards both ends of the metering roller.

[0023] Optionally, the metering powder roller is rotatably connected to the machine shell through a rolling bearing, the metering powder roller is provided with a skeleton oil seal and a wool felt around a central axis thereof, and the skeleton oil seal and the wool felt are located between the metering groove and the rolling bearing and abut against the inner wall of the machine shell.

[0024] By adopting the above technical scheme, since the metering powder roller is rotatably connected to the machine shell through a rolling bearing, the rolling bearing needs to be lubricated with lubricating oil. The skeleton oil seal can seal and isolate the lubricating oil of the rolling bearing, and the wool felt can further absorb and seal the lubricating oil and hinder the metal powder from escaping to the rolling bearing, thereby ensuring the normal operation of the rolling bearing.

[0025] Optionally, a sealing strip is arranged at the edge of the powder inlet of the powder inlet channel.

[0026] By adopting the above technical scheme, after the powder outlet end of the 3D printer is docked and mounted to the machine shell, there is still a gap between the powder outlet end of the 3D printer and the edge of the powder inlet of the powder inlet channel, and the sealing strip can prevent the metal powder from escaping from the gap, thereby reducing the waste of the metal powder and the pollution to the surrounding environment.

[0027] In a second aspect, the 3D printer provided by the utility model adopts the following technical scheme:

[0028] A 3D printer comprises the powder roller device for metering powder.

[0029] In summary, the utility model has at least one of the following beneficial technical effects:

[0030] 1. Since the metering powder roller is circumferentially provided with a plurality of metering grooves, the metal powder in the powder inlet channel can be transported to the powder outlet channel for powder outlet in the rotation of the metering powder roller in a single direction, the powder outlet efficiency is high, and the powder outlet is more smooth due to the movement direction, and since the metering grooves have the same content, the powder outlet amount can be accurately controlled.

[0031] 2. The guide block guides the path of the metal powder from the powder inlet channel to the metering groove, so as to reduce the dispersion of the metal powder in the machine shell and the possibility of the metal powder entering the powder outlet channel between the outer circular surface of the metering powder roller and the inner wall of the machine shell, thereby improving the accuracy of controlling the powder outlet amount and reducing the possibility of the metal powder accumulation and clamping between the outer circular surface of the metering powder roller and the inner wall of the machine shell.

[0032] 3. The machine shell is split into a first shell and a second shell which are detachably connected, and the guide block is clamped by the first shell and the second shell, so that the guide block can be replaced after long-term use and wear. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 is a schematic diagram of the overall structure of the utility model.

[0034] Figure 2 is Figure 1 is a schematic diagram of the sectional structure along line A-A in the middle.

[0035] Figure 3 is Figure 1 is a schematic diagram of the partial sectional structure along line B-B in the middle.

[0036] Figure 4 is Figure 3 is a schematic diagram of the enlarged structure of C part in the middle.

[0037] Mark explanation: 1, the casing; 11, the first shell; 111, the clamping part; 112, the fixed hole; 113, the fixed bolt; 12, the second shell; 121, the positioning groove; 2, the powder inlet channel; 21, the partition plate; 3, the powder outlet channel; 31, the partition part; 4, the metering powder roller; 41, the metering groove; 42, the powder collecting groove; 43, the boss; 5, the driving mechanism; 51, the driving motor; 52, the speed reducer; 53, the shaft coupling; 6, the guide block; 61, the guide port; 7, the rolling bearing; 71, the skeleton oil seal; 72, the wool felt; 8, the sealing strip. DETAILED DESCRIPTION

[0038] The following will be combined with the Figures 1-4 The utility model is further explained in detail.

[0039] The utility model discloses a kind of 3D printers, and 3D printer includes powder roller device for metering powder outlet.For Figure 1 And Figure 2 , powder roller device for metering powder outlet includes casing 1, and casing 1 is hollowly arranged.Casing 1 includes first shell 11 and second shell 12, and first shell 11 is located above second shell 12, and the upper end surface of second shell 12 is provided with a plurality of threaded holes.First shell 11 is provided with two rows of fixed holes 112, one row of fixed holes 112 is straight hole, and the other row of through hole inner wall is ladder shaft shape and large end is on, and two rows of fixed holes 112 of first shell 11 are all provided with fixed bolt 113, and fixed bolt 113 is inserted into threaded hole simultaneously and is screw-connected to second shell 12.First shell 11 is provided with powder inlet channel 2, and second shell 12 is provided with powder outlet channel 3, and powder inlet channel 2 and powder outlet channel 3 are communicated with each other.Second shell 12 is provided with metering powder roller 4, and metering powder roller 4 blocks the passageway between powder inlet channel 2 and powder outlet channel 3.

[0040] For Figure 1, the powder outlet end of the 3D printer and the powder inlet edge of the powder inlet channel 2 still have a gap after being connected and installed, the powder inlet edge of the powder inlet channel 2 is provided with a sealing strip 8, and the sealing strip 8 is arranged around the powder inlet. The sealing strip 8 can prevent the metal powder from escaping from the gap, reducing the waste of metal powder and the pollution to the surrounding environment.

[0041] With reference to Figure 1 , in order to facilitate the butt joint and fixation with the powder outlet end of the 3D printer, the upper end face of the first shell body 11 is inclined, the first shell body 11 is provided with a plurality of through holes, and the plurality of through holes are provided with bolts for being connected with the powder outlet end of the 3D printer. The first shell body 11 is also provided with a plurality of screw holes for inserting and threadedly connecting the bolts of the powder outlet end of the 3D printer, and the plurality of screw holes are also provided with a ring of sealing strips 8.

[0042] With reference to Figure 1 and Figure 3 , the two ends of the metering roller 4 are provided with rolling bearings 7, and the metering roller 4 is stably rotationally connected to the second shell body 12 through the rolling bearings 7. One end of the metering roller 4 is rotatably provided in the shell wall of the second shell body 12, and the other end of the metering roller 4 located outside the second shell body 12 is connected with a driving mechanism 5 through a shaft coupling 53. The driving mechanism includes a driving motor 51 and a speed reducer 52 connected in sequence, and the driving end of the speed reducer 52 is connected to the shaft coupling 53, so as to drive the metering roller 4 to rotate stably.

[0043] With reference to Figure 2 and Figure 3 , the outer circumferential surface of the metering roller 4 is provided with a plurality of metering grooves 41, the plurality of metering grooves 41 are circumferentially distributed around the central axis of the metering roller 4, the plurality of metering grooves 41 are arranged along the axis of the metering roller 4, and the capacities of the plurality of metering grooves 41 are the same.

[0044] When the 3D printer discharges powder, the metal powder first enters the shell body 1 through the powder inlet channel 2. Since the metering roller 4 blocks the passage between the powder inlet channel 2 and the powder outlet channel 3, the metal powder can only enter the metering groove 41 facing the powder inlet channel 2, and then the driving mechanism 5 drives the metering roller 4 to rotate, so that the metering groove 41 containing the metal powder rotates towards the powder outlet channel 3, so that the metal powder in the metering groove 41 falls into the powder outlet channel 3 to complete the powder discharge. Since the metering roller 4 is circumferentially provided with a plurality of metering grooves 41, the metering roller 4 can transport the metal powder in the powder inlet channel 2 to the powder outlet channel 3 for powder discharge through single direction rotation, the powder discharge efficiency is high, and the powder discharge is more smooth due to the movement direction. And because the capacities of the plurality of metering grooves 41 are the same, the powder discharge amount can be accurately controlled.

[0045] With reference to Figure 2 andFigure 3 A guide block 6 made of rubber is arranged between the first shell 11 and the second shell 12. The inner wall of the second shell 12 is provided with a positioning groove 121, and the guide block 6 is placed in the positioning groove 121. The first shell 11 abuts against the upper end surface of the guide block 6. The guide block 6 is provided with a guide port 61, and the upper end of the guide port 61 is connected to the edge of the powder inlet channel 2. The lower end of the guide port 61 is attached to the outer surface of the upper half of the metering roller 4. The opening edge of the powder inlet channel 2 is provided with a clamping portion 111, which is inserted into the guide port 61 and buckled to the opening edge of the guide port 61. The clamping portion 111 can position the guide block relative to the powder inlet channel 2 and connect the powder inlet channel 2 and the guide port 61, so that the metal powder can flow more smoothly from the powder inlet channel 2 into the guide port 61.

[0046] The guide block 6 guides the path of the metal powder from the powder inlet channel 2 to the metering groove 41, reducing the dispersion of metal powder in the machine shell 1 and the possibility of metal powder entering the powder outlet channel 3 between the outer surface of the metering roller 4 and the inner wall of the machine shell 1, thereby improving the accuracy of controlling the powder output. It can also reduce the possibility of metal powder accumulation between the outer surface of the metering roller 4 and the inner wall of the machine shell 1, thereby reducing the possibility of powder jamming. The rubber guide block 6 can be more closely attached to the metering roller 4, with less interference to the rotation of the metering roller 4, thereby further reducing the possibility of metal powder escaping through the gap between the guide block 6 and the outer surface of the metering roller 4, thereby reducing the possibility of powder jamming and leakage.

[0047] The first shell 11 and the second shell 12 are fixed by bolts to clamp the guide block 6, so that after long-term use of the guide block 6, the first shell 11 and the second shell 12 can be disassembled to facilitate replacement of the guide block 6. At the same time, the guide block 6 can also block the gap between the first shell 11 and the second shell 12, thereby reducing the possibility of metal powder escaping from the gap between the first shell 11 and the second shell 12 and improving the sealing of the machine shell 1.

[0048] Referring to Figure 1 and Figure 3 Due to the need for powder outlet position during 3D printing, the opening surface of the powder inlet channel 2 and the powder outlet channel 3 is usually rectangular with a long side. In order to reduce the possibility of deformation of the powder inlet channel 2 and the powder outlet channel 3 due to the long span, the inner wall of the powder inlet channel 2 is fixedly provided with a plurality of partition plates 21. The plurality of partition plates 21 are arranged at equal intervals along the long side direction of the opening surface of the powder inlet channel 2, and the plurality of partition plates 21 are perpendicular to the long side edge of the powder inlet channel 2. The plurality of partition plates 21 divide the powder inlet channel 2 into a plurality of independent spaces. The metering groove 41 and the discharge channel are both fixedly provided with a partition portion 31 corresponding to the position of the plurality of partition plates 21.

[0049] The powder inlet channel 2 is supported along its long direction by several partition plates 21, which can reduce the possibility of deformation of the powder inlet channel 2 due to excessive span. Similarly, the partition part 31 of the metering groove 41 and the discharge channel can reduce the possibility of deformation of the metering groove 41 and the discharge channel due to excessive span.

[0050] During the process of metal powder entering the metering groove 41 from the powder inlet channel 2, it is easy to fall on the outer cylindrical surface of the metering roller 4 at both ends, and there is a case that the metal powder continues to move and escape towards both ends of the metering roller 4. When the metal powder continues to move and escape towards both ends of the metering roller 4, it will affect the normal operation of the rolling bearing 7, and will also escape from the machine shell 1 through the rotating part of the metering roller 4 and the machine shell 1, thereby causing waste of metal powder and environmental pollution. Moreover, the metering roller 4 is rotatably connected to the machine shell 1 by the rolling bearing 7, and the rolling bearing 7 needs to be lubricated with lubricating oil. Referring to Figure 3 and Figure 4 , the two ends of the metering roller 4 are fixedly provided with a skeleton oil seal 71 and a wool felt 72 around the central axis, the wool felt 72 is located between the metering groove 41 and the rolling bearing 7, the skeleton oil seal 71 is located between the wool felt 72 and the rolling bearing 7, and the skeleton oil seal 71 and the wool felt 72 abut against the inner wall of the machine shell 1.

[0051] The skeleton oil seal 71 can seal and isolate the lubricating oil of the rolling bearing 7, and the wool felt 72 can further absorb and seal the lubricating oil, and also can hinder the escape of metal powder to the rolling bearing 7, thereby ensuring the normal operation of the rolling bearing 7.

[0052] Referring to Figure 3 and Figure 4 Since the wool felt 72 has limited hindering effect on metal powder, two powder collecting grooves 42 are formed at both ends of the metering roller 4, the two powder collecting grooves 42 are arranged around the central axis of the metering roller 4, and the two powder collecting grooves 42 are located on both sides of all the metering grooves 41. The metering roller 4 is fixedly connected with two bosses 43, the two bosses 43 are arranged around the central axis of the metering roller 4, the two bosses 43 are located at both ends of the metering roller 4, and the two bosses 43 are located on the side away from the two powder collecting grooves 42, and the two bosses 43 are in close contact with the wool felt 72 at both ends of the metering roller 4.

[0053] When the metal powder continues to move and disperse towards the two ends of the metering roller 4, the powder collecting groove 42 can collect the metal powder moving towards the two ends of the metering roller 4 and hinder the metal powder from continuing to move, and the two bosses 43 can further intercept the metal powder not collected by the powder collecting groove 42 to further hinder the metal powder from continuing to move and disperse towards the two ends of the metering roller 4, to further hinder the metal powder from dispersing to the rolling bearing 7, and to avoid the metal powder from dispersing out of the machine shell 1 through the penetration rotating part of the metering roller 4 and the machine shell 1.

[0054] The implementation principle of the powder rolling device for metering powder and the 3D printer is as follows: when the 3D printer discharges powder, the metal powder first enters the machine shell 1 through the powder inlet channel 2. Since the metering roller 4 blocks the passage between the powder inlet channel 2 and the powder outlet channel 3, the metal powder can only enter the metering groove 41 facing the powder inlet channel 2, and then the metering roller 4 is driven to rotate by the driving mechanism 5, so that the metering groove 41 containing the metal powder rotates towards the powder outlet channel 3, so that the metal powder in the metering groove 41 falls into the powder outlet channel 3 to complete the powder discharge. Since the metering roller 4 is circumferentially provided with a plurality of metering grooves 41, the metering roller 4 can transport the metal powder in the powder inlet channel 2 to the powder outlet channel 3 for powder discharge by rotating in a single direction, the powder discharging efficiency is high, and the powder discharging is more smooth due to the movement direction, and the powder is not easy to be stuck. Moreover, since the capacities of the plurality of metering grooves 41 are the same, the powder discharging amount can be accurately controlled.

[0055] The above are preferred embodiments of the present application, and do not limit the protection scope of the present application, so that: any equivalent changes made according to the structure, shape, principle of the present application should be covered within the protection scope of the present application.

Claims

1. A powder rolling device for metering out powder, characterized by: The application relates to a powder metering device, which comprises a casing (1), wherein an upper end and a lower end of the casing (1) are respectively provided with a powder inlet channel (2) and a powder outlet channel (3), a metering roller (4) is rotatably arranged in the casing (1), and the metering roller (4) blocks the passage between the powder inlet channel (2) and the powder outlet channel (3); the metering roller (4) is connected with a driving mechanism (5) for driving the metering roller (4) to rotate around a central axis of the metering roller (4), and the metering roller (4) is circumferentially provided with a plurality of metering grooves (41) with the same capacity around the central axis.

2. A powder roll device for metering out powder according to claim 1, characterized in that: A guide block (6) is fixedly arranged in the casing (1), the guide block (6) is provided with a guide opening (61), and the upper end of the guide opening (61) is connected to the edge of the powder inlet channel (2) and the lower end is attached to the outer circular surface of the upper half of the metering roller (4).

3. A powder roll device for metering out powder according to claim 2, characterized in that: The guide block (6) is made of rubber.

4. A powder roll device for metering out powder according to claim 2, characterized in that: The casing (1) comprises a first casing (11) and a second casing (12) which are detachably connected, the powder inlet channel (2) is arranged in the first casing (11), the metering roller (4) and the powder outlet channel are arranged in the second casing (12), the inner wall of the second casing (12) is provided with a positioning groove (121), the guide block (6) is placed in the positioning groove (121), and the first casing (11) abuts against the guide block (6).

5. The powder rolling device for metering out the powder according to claim 1, characterized by: A plurality of partition plates (21) are fixedly arranged in the powder inlet channel (2), the plurality of partition plates (21) are arranged in the length direction of the opening surface of the powder inlet channel (2) at intervals, and the metering grooves (41) and the powder outlet channel are respectively provided with a partition part (31) corresponding to the positions of the plurality of partition plates (21).

6. A powder roll device for metering out powder according to claim 1, characterized in that: The outer circular surfaces of the two ends of the metering roller (4) are respectively provided with powder collecting grooves (42) which are arranged around the central axis of the metering roller (4), and the two powder collecting grooves (42) are respectively located on the two sides of all the metering grooves (41).

7. A powder roll device for metering out powder according to claim 6, characterized in that: The metering roller (4) is rotatably connected to the casing (1) through a rolling bearing (7), the metering roller (4) is provided with a skeleton oil seal (71) and a wool felt (72) around the central axis, the skeleton oil seal (71) and the wool felt (72) are located between the metering grooves (41) and the rolling bearing (7), and the skeleton oil seal (71) and the wool felt (72) abut against the inner wall of the casing (1).

8. A powder roll device for metering out powder according to claim 1, characterized in that: The edge of the powder inlet opening of the powder inlet channel (2) is provided with a sealing strip (8).

9. A powder roll device for metering out powder according to claim 1, characterized in that: The powder metering device comprises the powder metering device according to any one of claims 1-9.

10. A 3D printer characterized by: ​

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