Powder spreading device

Abstract

The utility model belongs to the field of additive manufacturing, and relates to a powder spreading device which comprises a supporting seat, a powder spreading roller assembly, a vibration generating mechanism and a driving device. The driving device is arranged on the supporting seat and is connected with the powder spreading roller group; the driving device drives the powder spreading roller assembly to work; and the vibration generating mechanism is arranged on the powder spreading roller assembly. The utility model provides the powder spreading device capable of effectively improving the powder spreading density.

Description

Powder spreading device Technical Field

[0001] This utility model belongs to the field of additive manufacturing and relates to a powder spreading device, and more particularly to a vibration heating powder spreading device. Background Technology

[0002] Existing laser selective melting equipment powder spreading systems mostly use scrapers or powder spreading rollers for powder spreading. The powder spreading device only performs simple translation or translation plus rotation movements. Although it can meet the basic powder spreading requirements, there is still room for improvement in parameters such as powder spreading density. Summary of the Invention

[0003] In order to solve the above-mentioned technical problems in the background art, the present invention provides a powder spreading device that can effectively improve the powder spreading density.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A powder spreading device, characterized in that: the powder spreading device includes a support base, a powder spreading roller assembly, a vibration generating mechanism, and a driving device; the driving device is disposed on the support base and connected to the powder spreading roller assembly; the driving device drives the powder spreading roller assembly to work; the vibration generating mechanism is disposed on the powder spreading roller assembly.

[0006] The aforementioned vibration generating mechanism is a piezoelectric ceramic; the piezoelectric ceramic is one or more sets; when the piezoelectric ceramic is in multiple sets, the multiple sets of piezoelectric ceramic are evenly distributed on the powder spreading roller assembly.

[0007] The powder spreading roller assembly described above is a heated powder spreading roller assembly.

[0008] The aforementioned heated powder spreading roller assembly includes a powder spreading roller mounting base, a rotating shaft, a powder spreading roller, and a heating rod; the rotating shaft is axially mounted on the powder spreading roller mounting base; the powder spreading roller is mounted on the rotating shaft and rotates axially along the rotating shaft; the heating rod is placed inside the powder spreading roller and rotates synchronously with the powder spreading roller; the driving device is connected to the rotating shaft and drives the powder spreading roller to rotate through the rotating shaft; the vibration generating mechanism is mounted on the powder spreading roller mounting base.

[0009] The above-mentioned heated powder spreading roller assembly also includes a heating rod mounting tube and a powder spreading roller clamping component; the heating rod mounting tube is arranged inside the powder spreading roller along the axial direction of the powder spreading roller; the heating rod is placed in the heating rod mounting tube; the powder spreading roller clamping component is arranged at the end of the heating rod mounting tube and fills the space between the end of the heating rod mounting tube and the end of the powder spreading roller.

[0010] The aforementioned heated powder spreading roller assembly also includes a temperature probe installed inside the powder spreading roller.

[0011] The aforementioned heated powder spreading roller assembly also includes a bearing mounted on the powder spreading roller mounting base; the rotating shaft is mounted on the powder spreading roller mounting base via the bearing; and felt pressure rings are provided at both ends of the bearing.

[0012] The aforementioned heated powder spreading roller assembly also includes a counting sensor mounted on the rotating shaft.

[0013] The aforementioned driving device includes a synchronous belt, synchronous pulleys, and a power source; the power source is fixedly mounted on a support base; the synchronous pulleys include a first synchronous pulley and a second synchronous pulley; the power source is connected to the first synchronous pulley and drives the first synchronous pulley to rotate; the second synchronous pulley is fixedly mounted on a rotating shaft; the synchronous belt is wound around the first synchronous pulley and the second synchronous pulley; the power source is sequentially connected to the heated powder spreading roller assembly through the first synchronous pulley, the synchronous belt, and the second synchronous pulley.

[0014] The aforementioned power source is either a single-motor drive structure or a dual-motor drive structure.

[0015] The advantages of this utility model are:

[0016] This invention provides a powder spreading device, including a support base, a powder spreading roller assembly, a vibration generating mechanism, and a driving device. The driving device is mounted on the support base and connected to the powder spreading roller assembly. The driving device drives the powder spreading roller assembly to operate. The vibration generating mechanism is mounted on the powder spreading roller assembly. This invention uses a single-head heating rod placed inside the powder spreading roller to heat the roller, reducing the temperature gradient of the metal powder and the resulting residual stress, thus improving defects such as warping and cracking of parts. Simultaneously, a vibration generating mechanism is provided on the heated powder spreading roller assembly, which vibrates at a set frequency, amplitude, and direction to increase the powder spreading density. Clearly, heating and vibration methods can improve the powder spreading effect, enhance forming quality, and provide a technical foundation for high-precision forming. Attached Figure Description

[0017] Figure 1 is a top view of the powder spreading device provided by this utility model.

[0018] Figure 2 is a cross-sectional view of the heated powder spreading roller assembly used in this utility model.

[0019] Figure 3 is a cross-sectional view of the heated powder spreading roller assembly used in another embodiment of the present invention.

[0020] Figure 4 is a schematic diagram of the arrangement of the piezoelectric ceramics used in this utility model;

[0021] Figure 5 is a top view of the dual-motor powder spreading device provided by this utility model.

[0022] Figure 6 is a top view of the single-motor central powder spreading device provided by this utility model.

[0023] Figure 7 is a side view of the vertical powder spreading device provided by this utility model.

[0024] in:

[0025] 1-Motor; 2-Piezoelectric ceramic; 3-Synchronous idler wheel; 4-Support base; 5-Synchronous belt; 6-Synchronous belt pulley; 7-Guide rail; 8-Screw; 9-Heated powder spreading roller assembly; 901-Powder spreading roller mounting base; 902-Temperature probe; 903-Slip ring; 904-Rotating shaft; 905-Reserved cavity; 906-Bearing; 907-Felt pressure ring; 908-Powder spreading roller clamping component; 909-Heating rod; 910-Powder spreading roller; 911-Heating rod mounting tube; 912-Counting sensor; 913-Side plate; 914-Dust cover; 10-Linked rotating shaft; 11-Motor mounting base. Detailed Implementation

[0026] Referring to Figures 1, 4, and 5, this utility model provides a powder spreading device, including a support base 4, a powder spreading roller assembly, a vibration generating mechanism, and a driving device. The driving device is mounted on the support base 4 and connected to the powder spreading roller assembly; the driving device drives the powder spreading roller assembly to work; the vibration generating mechanism is mounted on the powder spreading roller assembly. In practical use, the support base 4 drives the powder spreading roller assembly to work through the driving device. Under the action of external drive, the support base 4 and the powder spreading roller assembly move axially along the guide rail 7. The vibration generating mechanism can drive the powder spreading roller assembly to vibrate at a set vibration frequency, vibration amplitude, and vibration direction, thereby increasing the powder spreading density.

[0027] For example, the vibration generating mechanism can be a piezoelectric ceramic 2 or any other existing structure or device capable of generating vibration waves. The piezoelectric ceramic 2 is one or more sets; when there are multiple sets of piezoelectric ceramics, the multiple sets of piezoelectric ceramics are evenly distributed on the powder spreading roller assembly 9.

[0028] Referring to Figures 2 and 3, the powder spreading roller assembly used in this invention can be a heated powder spreading roller assembly 9. Because of the use of the heated powder spreading roller assembly 9, the powder to be spread can be heated during the powder spreading process, reducing the temperature gradient of the metal powder and the resulting residual stress, thus improving defects such as warping, deformation, and cracking of the parts. As an example, the powder spreading device provided by this invention is connected to a laser selective melting device via a guide rail to realize the corresponding powder spreading operation.

[0029] Referring to Figures 2 and 3, the heated powder spreading roller assembly 9 of this invention includes a powder spreading roller mounting base 901, a rotating shaft 904, a powder spreading roller 910, and a heating rod 909. The rotating shaft 904 is axially mounted on the powder spreading roller mounting base 901. The powder spreading roller 910 is mounted on the rotating shaft 904 and rotates axially along the rotating shaft 904. The heating rod 909 is placed inside the powder spreading roller 910 and rotates synchronously with the powder spreading roller 910. The driving device is connected to the rotating shaft 904 and drives the powder spreading roller 910 to rotate through the rotating shaft 904. This invention heats the powder to be spread through the heating rod 909 and the powder spreading roller 910. For example, a dust cover 914 is installed on the powder spreading roller mounting base 901 to protect the connection between the driving device and the rotating shaft 904 from dust, ensuring stable operation of the device over a long period.

[0030] Furthermore, to limit the position of the heating rod 909 or to securely fix the heating rod 909 within the powder spreading roller 910, the heating rod 909 is placed inside a hollow tubular rotating shaft (i.e., the heating rod mounting tube 911 shown in Figures 2 and 3). The outer side of the heating rod mounting tube 911 is fitted into the powder spreading roller 910 without relative sliding. Simultaneously, a powder spreading roller clamping member 908 is provided at the end of the heating rod mounting tube 911, filling the space between the end of the heating rod mounting tube 911 and the end of the powder spreading roller 910. For example, the powder spreading roller clamping member 908 can be made of a flexible material, such as a rubber gasket. For example, the powder spreading roller clamping member 908 is equal to or smaller than the diameter of the powder spreading roller 910, and the powder spreading roller clamping member 908 and the heating rod mounting tube 911 can be fastened together by screws.

[0031] Referring to Figure 3, in order to control the temperature of the heating rod 909, the heating powder spreading roller assembly 9 of this invention also includes a temperature probe 902 disposed inside the powder spreading roller 910. The temperature probe 902 is placed in a reserved cavity 905 inside the powder spreading roller 910. For example, the wiring harnesses of the heating rod 909 and the temperature probe 902 are led out together through the reserved cavity 905 and connected to a slip ring 903 fitted at the end of the rotating shaft 904. The slip ring 903 is then led out to a power supply and monitoring device. Simultaneously, the slip ring 903 on the other side of the powder spreading roller 910 is replaced by a counting sensor 912 to measure the motion parameters of the powder spreading roller.

[0032] For example, the rotation of the powder spreading roller 910 is achieved through the switching between static and dynamic states via two bearings 906 on both sides and their adjacent felt pressure rings 907. The outer side of the bearing 906 is in close contact with the powder spreading roller mounting base 901, and is fixedly connected to the powder spreading roller mounting base 901 via a side plate 913 placed between the bearing 906 and the powder spreading roller mounting base 901. For example, the felt pressure ring 907 includes a clamping element and a felt ring, which are installed on both sides of the bearing 906. The switching between static and dynamic states of the inner and outer rings of the bearing 906 is achieved through different clamping elements. The felt ring is installed between adjacent parts of each clamping element to achieve a dynamic dustproof effect and to achieve sliding friction with the powder spreading roller mounting base 901 and the rotating shaft 904. It should be noted that the heated powder spreading roller assembly used in Figures 2 and 3, especially the powder spreading roller mounting base 901, are two different manifestations. In Figure 2, the powder spreading roller mounting base 901 covers the outside of the synchronous pulley 6; in Figure 3, the powder spreading roller mounting base 901 covers the outside of the bearing 906 but does not cover the synchronous pulley 6. However, regardless of the method or structure, the purpose is to provide stable support for the powder spreading roller 910.

[0033] For example, the piezoelectric ceramic 2 is clamped and fixed between the support base 4 and the powder spreading roller mounting base 901 by several screws 8. Both the support base 4 and the powder spreading roller mounting base 901 have square slots for placing the piezoelectric ceramic 2. Two round holes are formed within the square slot of the support base 4 for leading out the piezoelectric ceramic wiring harness. The placement position, parameters, and quantity of the piezoelectric ceramic 2 are selected based on the required mass and amplitude of the powder spreading roller mechanism, ensuring that the powder spreading roller vibration reaches the expected frequency and amplitude. The dimensions (including thread specification, screw insertion length, and screw stiffness) and number of screws 8 are determined based on the mass of the powder spreading roller assembly, the selected piezoelectric ceramic stiffness, and the required amplitude, ensuring a stable connection between the powder spreading roller and the support base and operation according to the target vibration parameters.

[0034] Referring to Figures 1 and 4, the driving device used in this utility model includes a synchronous belt 5, a synchronous pulley 6, and a power source; the power source is fixedly mounted on the support base 4; the synchronous pulley 6 includes a first synchronous pulley and a second synchronous pulley; the power source is connected to the first synchronous pulley and drives the first synchronous pulley to rotate; the second synchronous pulley is fixedly mounted on the rotating shaft 904; the synchronous belt 5 is wound around the first synchronous pulley and the second synchronous pulley; the power source is connected to the heated powder spreading roller assembly 9 in sequence through the first synchronous pulley, the synchronous belt 5, and the second synchronous pulley.

[0035] The power source can be a single-motor drive structure or a dual-motor drive structure. Referring to Figures 1 and 6, both employ a single-motor drive structure. For example, referring to Figure 1, the single-motor drive structure can be parallel to the end of the heated powder spreading roller assembly 9. In this case, the heated powder spreading roller assembly 9 and the motor 1 are connected to the guide rail 7 via the support base 4. One side of the support base 4 is considered rigid, so the vibration generated by the piezoelectric ceramic 2 will not be transmitted to the motor 1 via the synchronous belt 5. The rotation of the heated powder spreading roller assembly 9 is driven by the motor 1 via the synchronous pulley 6 and the synchronous belt 5. On the other side, to balance the radial torque generated by the tension of the synchronous belt 5 on the motor 1 side, a synchronous pulley 6 and a synchronous idler pulley 3 of the same specifications are connected to the synchronous belt 5. For example, referring to Figure 6, a single-motor drive structure can be placed parallel to the center of the heated powder spreading roller assembly 9. In this case, the motor 1 is fixed on the support base 4, and an additional connecting shaft 10 is driven by a synchronous belt 5. The connecting shaft 10 is placed parallel to the powder spreading roller 9, and the central axis of the synchronous pulley of the connecting shaft 10 and the central axis of the synchronous pulley of the powder spreading roller 9 are located on the same horizontal plane. The synchronous pulleys on both sides of the powder spreading roller are driven to rotate by this shaft, which can also make the powder spreading roller achieve torque balance in both the axial and radial directions.

[0036] Referring to Figure 5, a dual-motor drive structure is adopted. The scheme shown in Figure 5 is a simple variation of the scheme shown in Figure 1. That is, a motor 1 of the same specification is used to replace the synchronous idler wheel 3 in the scheme shown in Figure 1. At the same time, the two motors 1 are arranged symmetrically. After setting the same parameters, it is ensured that the two motors run synchronously, so that the two motors 1 drive the heated powder spreading roller assembly 9 at the same time, so that the axial and radial torques of the heated powder spreading roller assembly 9 reach a balanced state.

[0037] Referring to Figure 7, which is a side view of the vertical powder spreading device provided by this utility model, unlike Figure 1 (flat spreading structure), the central axis of the motor 1 and the central axis of the powder spreading roller 910 are located on the same horizontal plane. That is, the motor 1 is fixed to the vertical direction of the powder spreading roller 910 through the motor mounting base 11, so that the central axis of the motor 1 and the central axis of the powder spreading roller are located on the same vertical plane. This structure can reduce the device size of the powder spreading roller along the direction of movement and has a better dustproof effect. Similarly, a synchronous idler pulley of the same specification as the current synchronous belt pulley or a motor of the same specification can be arranged on the other side of the powder spreading roller 910 to balance the radial torque of the powder spreading roller 910.

Claims

1. A powder spreading device, characterized in that: The powder spreading device includes a support base (4), a powder spreading roller assembly, a vibration generating mechanism, and a driving device; the driving device is mounted on the support base (4) and connected to the powder spreading roller assembly; the driving device drives the powder spreading roller assembly to work; the vibration generating mechanism is mounted on the powder spreading roller assembly.

2. The powder spreading device according to claim 1, characterized in that: The vibration generating mechanism is a piezoelectric ceramic (2); the piezoelectric ceramic (2) is one or more sets; when the piezoelectric ceramic (2) is multiple sets, the multiple sets of piezoelectric ceramics are evenly distributed on the powder spreading roller assembly.

3. The powder spreading device according to claim 1 or 2, characterized in that: The powder spreading roller assembly is a heated powder spreading roller assembly (9).

4. The powder spreading device according to claim 3, characterized in that: The heated powder spreading roller assembly (9) includes a powder spreading roller mounting base (901), a rotating shaft (904), a powder spreading roller (910), and a heating rod (909); the rotating shaft (904) is arranged on the powder spreading roller mounting base (901) along the axial direction of the powder spreading roller mounting base (901); the powder spreading roller (910) is mounted on the rotating shaft (904) and rotates along the axial direction of the rotating shaft (904); the heating rod (909) is placed inside the powder spreading roller (910) and rotates synchronously with the powder spreading roller (910); the driving device is connected to the rotating shaft (904) and drives the powder spreading roller (910) to rotate through the rotating shaft (904); the vibration generating mechanism is arranged on the powder spreading roller mounting base (901).

5. The powder spreading device according to claim 4, characterized in that: The heated powder spreading roller assembly (9) further includes a heating rod mounting tube (911) and a powder spreading roller clamping member (908); the heating rod mounting tube (911) is arranged along the axial direction of the powder spreading roller (910) inside the powder spreading roller (910); the heating rod (909) is placed in the heating rod mounting tube (911); the powder spreading roller clamping member (908) is arranged at the end of the heating rod mounting tube (911) and fills the space between the end of the heating rod mounting tube (911) and the end of the powder spreading roller (910).

6. The powder spreading device according to claim 5, characterized in that: The heated powder spreading roller assembly (9) also includes a temperature probe (902) disposed inside the powder spreading roller (910).

7. The powder spreading device according to claim 6, characterized in that: The heated powder spreading roller assembly (9) also includes a bearing (906) disposed on the powder spreading roller mounting base (901); the rotating shaft (904) is disposed on the powder spreading roller mounting base (901) via the bearing (906); and felt pressure rings (907) are provided at both ends of the bearing (906).

8. The powder spreading device according to claim 7, characterized in that: The heated powder spreading roller assembly (9) also includes a counting sensor (912) disposed on the rotating shaft (904).

9. The powder spreading device according to claim 8, characterized in that: The driving device includes a synchronous belt (5), a synchronous pulley (6), and a power source; the power source is fixedly mounted on the support base (4); the synchronous pulley (6) includes a first synchronous pulley and a second synchronous pulley; the power source is connected to the first synchronous pulley and drives the first synchronous pulley to rotate; the second synchronous pulley is fixedly mounted on the rotating shaft (904); the synchronous belt (5) is wound around the first synchronous pulley and the second synchronous pulley; the power source is connected to the heated powder spreading roller assembly (9) in sequence through the first synchronous pulley, the synchronous belt (5), and the second synchronous pulley.

10. The powder spreading device according to claim 9, characterized in that: The power source is either a single-motor drive structure or a dual-motor drive structure.

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