High-precision and high-rigidity synchronizing device and tool setting method

Abstract

The invention relates to the technical field of metal 3D printing, and provides a high-precision and high-rigidity synchronizing device and a knife adjusting method.The high-precision and high-rigidity synchronizing device comprises a bottom plate and a scraper, a knife rest is horizontally and slidably connected to the bottom plate, the knife rest is in threaded connection with an adjusting bolt used for adjusting the height of the scraper, and a bearing is arranged in the scraper; the scraper is connected with the adjusting bolt through the locking bolt movably arranged in the bearing in a sleeved mode, the locking bolt is connected into the adjusting bolt in a threaded mode, rigid connection of the scraper and the knife rest is achieved through threaded connection of the adjusting bolt and the knife rest and threaded connection of the locking bolt and the adjusting bolt, and the problem of insufficient rigidity caused by traditional elastic connection is avoided. According to the powder spreading device, the problem that in the powder spreading process, the scraper vibrates when encountering a high point of powder is solved, the rigidity and the powder spreading effect of the scraper are improved, through the bearing embedded in the scraper, the scraper cannot shake and deviate due to rotation of the locking bolt in the tool adjusting process, and the adjusting precision is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of metal 3D printing, and in particular to a high-precision and high-rigidity synchronization device and a tool adjustment method. Background Art

[0002] Selective laser melting (SLM), also known as powder-laying 3D printing technology, is one of the important manufacturing technologies in the field of 3D printing. This technology uses laser as energy to scan the flat metal powder in layers according to the path planned in the 3D model view, so that it melts and connects and solidifies to achieve metallurgical welding. In this way, high-density and high-strength metal components corresponding to the 3D model can be quickly manufactured.

[0003] Powder spreading is a key link in the SLM process, which directly affects the printing accuracy and processing efficiency. The main powder spreading methods on the market currently include single-scraper one-way powder spreading, double-scraper two-way powder spreading and single-scraper two-way powder spreading. Among them, single-scraper two-way powder spreading has become a more commonly used powder spreading method on the market because of its good balance between efficiency, cost and printing quality. In this method, the scraper is linked with a large-capacity powder receiver, so that the powder receiver drops powder twice at the initial position and the predetermined position, thereby realizing the reciprocating powder spreading of a single scraper.

[0004] However, after the scraper is installed, it needs to be adjusted. At present, most scraper adjustment mechanisms use elastic connections, which leads to poor connection rigidity and the problem of unstable position. In addition, the scraper adjustment mechanism is cumbersome to operate during blade adjustment and the adjustment accuracy is difficult to ensure. Summary of the invention

[0005] The purpose of the present invention is to provide a high-precision and high-rigidity synchronization device and a knife adjustment method, which solves the problems of poor rigidity of existing scraper connections, complicated knife adjustment operations and difficulty in ensuring adjustment accuracy.

[0006] The present invention is achieved through the following technical scheme: a high-precision and high-rigidity synchronization device, including a base plate and a scraper, a tool holder is horizontally slidably connected to the base plate, the tool holder is threadedly connected to an adjusting bolt for adjusting the height of the scraper, a bearing is provided in the scraper, the scraper is connected to the adjusting bolt through a locking bolt movably sleeved in the bearing, and the locking bolt is threadedly connected in the adjusting bolt.

[0007] Furthermore, the direction of the external thread of the adjusting bolt is opposite to the direction of the external thread of the locking bolt.

[0008] Furthermore, a synchronous transmission assembly is arranged on the bottom plate, and the synchronous transmission assembly is connected to both sides of the tool holder through a connecting block.

[0009] Furthermore, the synchronous transmission assembly includes a motor and a transmission shaft driven by the motor, both ends of the transmission shaft are connected to a screw rod via bevel gear transmission, and the connecting block is threadedly connected to the screw rod.

[0010] Furthermore, the synchronous transmission assembly is two independent belt transmission mechanisms, and the connecting block is fixed on the belt of the belt transmission mechanism.

[0011] Furthermore, the tool holder is provided with a connection hole for connecting the adjusting bolt, a scale is arranged on the surface of the tool holder in the circumferential direction of the connection hole, and an indicator line is arranged on the adjusting bolt.

[0012] Furthermore, the bearing is a self-lubricating angular contact ball bearing, including an outer ring and an inner ring, the outer ring is interference fit with the scraper, and the inner ring is clearance fit with the locking bolt.

[0013] Furthermore, a level block for leveling the scraper is provided between the scraper and the base plate.

[0014] Furthermore, two adjusting bolts are arranged on the tool holder.

[0015] A knife adjustment method comprises the following steps:

[0016] Step 1: Install the tool holder and place the equal height block under the tool holder;

[0017] Step 2: Place the scraper on the equal height block, and turn the adjusting bolt so that the lower end of the adjusting bolt just touches the bearing;

[0018] Step 3: Tighten the locking bolts, remove the leveling blocks, and complete the leveling of the scraper.

[0019] The present invention has at least the following advantages and beneficial effects:

[0020] (1) The rigid connection between the scraper and the tool holder is achieved through the threaded connection between the adjusting bolt and the tool holder, and the threaded connection between the locking bolt and the adjusting bolt, thereby avoiding the problem of insufficient rigidity caused by the traditional elastic connection, solving the vibration problem when the scraper encounters the high point of powder during the powder spreading process, and improving the scraper rigidity and powder spreading effect.

[0021] (2) Through the bearing embedded in the scraper, the scraper will not shake or deviate due to the rotation of the locking bolt during the adjustment process, thereby improving the adjustment accuracy.

[0022] (3) By adjusting the reverse thread settings of the bolt and the locking bolt, an axial preload is generated when the locking bolt is tightened, eliminating the thread pair clearance and improving the connection rigidity. At the same time, the reverse thread has a self-locking function to prevent the bolt from loosening due to equipment vibration or long-term use.

[0023] (4) Through the coordination of the equal height block and the adjusting bolt, the leveling process is simple and intuitive, without the need to adjust the base plate or conduct multiple trial paving, thus achieving fast and accurate tool setting. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A cross-sectional view of a high-precision and high-rigidity synchronization device provided by the present invention.

[0025] Figure 2 A schematic structural diagram of a high-precision and high-rigidity synchronization device provided in Embodiment 1 of the present invention.

[0026] Figure 3 A top view of a high-precision and high-rigidity synchronization device provided in Embodiment 1 of the present invention.

[0027] Figure 4 A schematic structural diagram of a high-precision and high-rigidity synchronization device provided in Embodiment 2 of the present invention.

[0028] Figure 5 A top view of a high-precision and high-rigidity synchronization device provided in Embodiment 2 of the present invention.

[0029] Figure 6 The present invention provides a flow chart of a knife adjustment method.

[0030] Figure numerals: 1-base plate, 2-tool holder, 20-connecting hole, 3-scraper, 4-adjusting bolt, 5-bearing, 6-locking bolt, 7-synchronous transmission assembly, 71-motor, 72-transmission shaft, 73-screw, 74-belt transmission mechanism, 8-connecting block, 9-equal height block. DETAILED DESCRIPTION

[0031] The following is a specific implementation method in conjunction with the accompanying drawings.

[0032] Embodiment 1

[0033] like Figures 1 to 3As shown, in this embodiment, a high-precision and high-rigidity synchronization device is mainly disclosed, which has an efficient and reliable structure, simple assembly, and is easy to maintain and repair. Its structure includes a base plate 1 and a scraper 3. A tool holder 2 is horizontally slidably connected to the base plate 1, and an adjusting bolt 4 for adjusting the height of the scraper 3 is threadedly connected to the tool holder 2. A bearing 5 is arranged inside the scraper 3. The scraper 3 is connected to the adjusting bolt 4 through a locking bolt 6 movably sleeved in the bearing 5, and the locking bolt 6 is threadedly connected in the adjusting bolt 4. Specifically, the base plate 1 is horizontally installed in the printing cabin of the equipment as a supporting base for printing metal components. The tool holder 2 is horizontally slidably connected above the base plate 1 for connecting the scraper 3. The rigid connection between the scraper 3 and the tool holder 2 is achieved by threading the adjusting bolt 4 and the tool holder 2, and the locking bolt 6 and the adjusting bolt 4. The problem of insufficient rigidity caused by the traditional elastic connection is avoided, and the vibration problem of the scraper 3 when encountering the high point of the powder during the powder spreading process is solved, thereby improving the rigidity of the scraper 3 and the powder spreading effect. At the same time, through the bearing 5 embedded in the scraper 3, during the blade adjustment process, when the locking bolt 6 is rotated to relatively fix the scraper 3 and the blade holder 2, the scraper 3 will not shake or deviate due to the rotation of the locking bolt 6, thereby improving the adjustment accuracy.

[0034] Furthermore, in a specific implementation, the external thread direction of the adjusting bolt 4 provided in the embodiment of the present invention is opposite to the external thread direction of the locking bolt 6. Specifically, the reverse thread design generates an axial preload when tightening the locking bolt 6, eliminates the thread pair clearance, and improves the connection rigidity. At the same time, the reverse thread has a self-locking function to prevent the bolt from loosening due to equipment vibration or long-term use.

[0035] Furthermore, in a specific implementation, a synchronous transmission assembly 7 is provided on the bottom plate 1 provided in the embodiment of the present invention, and the synchronous transmission assembly 7 is connected to both sides of the tool holder 2 through a connecting block 8. Specifically, the synchronous transmission assembly 7 is a packaged transmission component as a whole, and both sides of the tool holder 2 are connected to the synchronous transmission assembly 7 through the connecting block 8, so as to ensure that both sides of the tool holder 2 are synchronized when moving horizontally, solve the problem of bilateral cumulative error caused by the existing unilateral drive, avoid uneven powder spreading caused by the deflection of the scraper 3, and improve the stability and reliability of the movement of the tool holder 2.

[0036] Preferably, in a specific implementation, the synchronous transmission assembly 7 provided in the embodiment of the present invention includes a motor 71 and a transmission shaft 72 driven by the motor 71, and the two ends of the transmission shaft 72 are respectively connected with a screw rod 73 by bevel gear transmission, and the connecting block 8 is threadedly connected with the screw rod 73. Specifically, the motor 71 is connected to the middle position of the transmission shaft 72 through a gear set, and the axial direction of the transmission shaft 72 is perpendicular to the moving direction of the scraper 3. The motor 71 and the transmission shaft 72 are arranged at one end of the bottom plate 1 to avoid interference with the movement of the scraper 3. The screw rods 73 on both sides are arranged parallel to the moving direction of the scraper 3, and a guide rail cooperating with the screw rod 73 is also arranged parallel to one side of the screw rod 73. The bevel gears arranged at both ends of the transmission shaft 72 are respectively meshed with the bevel gears arranged at the ends of the screw rods 73 on both sides, and the transmission direction is changed, and the screw rod 73 rotates to achieve the smooth movement of the tool holder 2. In addition, the bevel gear transmission of the transmission shaft 72 and the screw rod 73 can be replaced by other high-rigidity transmission methods, such as worm gear transmission.

[0037] Furthermore, in a specific implementation, the tool holder 2 provided in the embodiment of the present invention is provided with a connection hole 20 for connecting the adjusting bolt 4, a scale is provided on the surface of the tool holder 2 in the circumferential direction of the connection hole 20, and an indicator line is provided on the adjusting bolt 4. The scale and the indicator line are used in conjunction to achieve quantitative adjustment of the height of the scraper 3, meeting the strict requirements of metal additive manufacturing on the thickness of the powder. The operator does not need to rely on external measuring tools, and can directly complete the adjustment through the scale reading, thereby improving efficiency.

[0038] Furthermore, in a specific implementation, the bearing 5 provided in the embodiment of the present invention is a self-lubricating angular contact ball bearing, including an outer ring and an inner ring, the outer ring and the scraper 3 have an interference fit, and the inner ring and the locking bolt 6 have a clearance fit. Specifically, the angular contact ball bearing 5 can withstand axial and radial loads, and adapt to the complex stress conditions of the scraper 3 during the powder spreading process. The design of the interference fit between the outer ring and the scraper 3 and the clearance fit between the inner ring and the locking bolt 6 isolates the movement of the locking bolt 6 sleeved in the inner ring from the scraper 3, so that the rotation of the locking bolt 6 will not affect the stability of the scraper 3.

[0039] Furthermore, in a specific implementation, a height-contour block 9 for leveling the scraper 3 is provided between the scraper 3 and the bottom plate 1 provided in the embodiment of the present invention. The height-contour block 9 serves as a reference block to simplify the leveling process of the scraper 3, reduce dependence on the operator's experience, ensure the parallelism between the scraper 3 and the bottom plate 1, and improve the uniformity of powder spreading.

[0040] Furthermore, in a specific implementation, two adjusting bolts 4 are provided on the tool holder 2 provided in the embodiment of the present invention. The two adjusting bolts 4 are symmetrically arranged on both sides of the tool holder 2 to achieve independent adjustment of the two sides of the scraper 3, further improving the parallelism between the scraper 3 and the base plate 1. At the same time, the double-bolt structure further enhances the connection rigidity between the scraper 3 and the tool holder 2, reducing vibration and displacement during the powder spreading process. It should be noted that the thread direction and initial turning angle of the two adjusting bolts 4 connected to the tool holder 2 are consistent, and the scale readings of the indicator lines on the two adjusting bolts 4 can be checked to ensure that the height changes on both sides are synchronized during the adjustment process, thereby avoiding adjustment errors caused by thread differences and achieving precise parallelism calibration between the scraper 3 and the base plate 1.

[0041] Embodiment 2

[0042] like Figure 4 , Figure 5 As shown, in this embodiment, the main structure is completely consistent with the first embodiment, and the difference is that the synchronous transmission assembly 7 is two independent belt transmission mechanisms 74, and the connecting block 8 is fixed on the belt of the belt transmission mechanism 74. Specifically, the two independent belt transmission mechanisms 74 are driven by independent synchronous motors 71, respectively, eliminating the cumulative synchronization deviation generated on both sides when the single motor 71 is driven, and improving the powder spreading quality, powder spreading accuracy and powder spreading stability. At the same time, the belt transmission runs smoothly, has low noise, and is easy to maintain and replace.

[0043] Embodiment 3

[0044] like Figure 6 As shown, in this embodiment, a knife adjustment method based on embodiment 1 or embodiment 2 is mainly disclosed, comprising the following steps:

[0045] Step 1, install the tool holder 2 and place the equal height block 9 under the tool holder 2;

[0046] Step 2: Place the scraper 3 on the height-contact block 9, and turn the adjusting bolt 4 so that the lower end of the adjusting bolt 4 just contacts the bearing 5; through the cooperation of the height-contact block 9 and the adjusting bolt 4, the leveling process is simple and intuitive, without the need to adjust the base plate 1 or multiple trial paving, thus achieving fast and accurate knife alignment.

[0047] Step 3: Tighten the locking bolt 6, remove the leveling block 9, and complete the leveling of the scraper 3.

Claims

1. A high-precision and high-rigidity synchronization device, characterized in that: The invention comprises a base plate (1) and a scraper (3); a blade holder (2) is horizontally slidably connected to the base plate (1); an adjusting bolt (4) for adjusting the height of the scraper (3) is threadedly connected to the blade holder (2); a bearing (5) is arranged inside the scraper (3); the scraper (3) is connected to the adjusting bolt (4) via a locking bolt (6) movably sleeved inside the bearing (5); and the locking bolt (6) is threadedly connected inside the adjusting bolt (4).

2. A high-precision and high-rigidity synchronization device according to claim 1, characterized in that: The direction of the external thread of the adjusting bolt (4) is opposite to the direction of the external thread of the locking bolt (6).

3. A high-precision and high-rigidity synchronization device according to claim 1, characterized in that: A synchronous transmission assembly (7) is provided on the base plate (1), and the synchronous transmission assembly (7) is connected to two sides of the tool holder (2) via a connecting block (8).

4. A high-precision and high-rigidity synchronization device according to claim 3, characterized in that: The synchronous transmission assembly (7) comprises a motor (71) and a transmission shaft (72) driven by the motor (71), both ends of the transmission shaft (72) are connected to a screw rod (73) via bevel gear transmission, and the connection block (8) is threadedly connected to the screw rod (73).

5. A high-precision and high-rigidity synchronization device according to claim 3, characterized in that: The synchronous transmission assembly (7) is composed of two independent belt transmission mechanisms (74), and the connecting block (8) is fixed on the belt of the belt transmission mechanism (74).

6. A high-precision and high-rigidity synchronization device according to claim 1, characterized in that: The tool holder (2) is provided with a connection hole (20) for connecting the adjustment bolt (4); a scale is provided on the surface of the tool holder (2) in the circumferential direction of the connection hole (20); and an indicator line is provided on the adjustment bolt (4).

7. A high-precision and high-rigidity synchronization device according to claim 1, characterized in that: The bearing (5) is a self-lubricating angular contact ball bearing, comprising an outer ring and an inner ring, the outer ring having an interference fit with the scraper (3), and the inner ring having a clearance fit with the locking bolt (6).

8. A high-precision and high-rigidity synchronization device according to claim 1, characterized in that: A level block (9) for leveling the scraper (3) is provided between the scraper (3) and the bottom plate (1).

9. A high-precision and high-rigidity synchronization device according to claim 1, characterized in that: The tool holder (2) is provided with two adjusting bolts (4).

10. A tool adjustment method based on a high-precision and high-rigidity synchronization device according to any one of claims 1 to 9, characterized in that: The following steps are involved: Step 1: Install the tool holder (2) and place the equal height block (9) below the tool holder (2); Step 2: Place the scraper (3) on the equal height block (9), and rotate the adjusting bolt (4) so ​​that the lower end of the adjusting bolt (4) just contacts the bearing (5); Step 3: Tighten the locking bolt (6), remove the leveling block (9), and complete the leveling of the scraper (3).

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