CN102430860A - Mobile mirror device - Google Patents

Abstract

A mobile galvanometer device, belonging to a laser rapid prototyping system, overcomes the limitation of limited forming space in the fixed working mode of the existing galvanometer scanning mechanism, and avoids the problem of increasing hardware cost and complexity by adopting a multi-galvanometer scanning mechanism. The invention includes a bottom plate, a guide rail, a crossbeam, an X-direction synchronous belt, an X-direction synchronous pulley and an X-direction servo motor. The X-direction synchronous pulley and the X-direction servo motor are fixed next to the guide rail on the bottom plate, and the crossbeam perpendicular to the guide rail passes through the X-direction sliding The block is slidably matched with the two guide rails, and one end of the beam is fixed on the X-direction synchronous belt; the vibrating mirror scanning mechanism is fixed on the beam, or the Y-direction synchronous pulley and the Y-direction servo motor are fixed on the beam, and the vibrating mirror scanning mechanism passes through the Y-direction sliding The block is slidingly matched with the beam, and one end of the Y-direction slider is fixed on the Y-direction synchronous belt. The invention expands the forming space, reduces the cost of hardware, reduces the complexity of control, software and technology, and is suitable for the manufacture of large-sized and complex parts.

Description

A mobile vibrating mirror device

technical field

The invention belongs to a laser rapid prototyping system, in particular to a mobile vibrating mirror device.

Background technique

Rapid prototyping technology was developed on the basis of rapid prototyping technology that appeared in the 1980s. Among them, the rapid prototyping technology represented by Selective Laser Sintering (SLS) technology uses laser as an energy source and uses three-dimensional CAD data, scan the layered slice area, sinter the material in this area, and then continue to circulate, layer by layer to form a product. Laser coherence is good, energy is concentrated, and the temperature of the laser spot is extremely high. It can partially or completely melt polymer, metal or ceramic powder, and realize sintering or solidification bonding between powder particles. Compared with other rapid prototyping methods, it can form a wide range of materials. , thus using laser as an energy source is widely used in rapid prototyping technology.

At present, in the laser rapid prototyping system, there are two scanning methods: XY linear guide rail type and galvanometer scanning type. The scanning method of XY linear guideway is realized by moving the laser head in the XY direction. Due to the large moving inertia, the scanning speed is low and the stability is poor. It is generally used in the forming system for the purpose of process research; the vibrating mirror The scanning type is realized by the galvanometer scanning mechanism. The galvanometer scanning mechanism is mainly composed of a scanning motor, a mirror and a servo drive unit. It can perform high-speed and accurate scanning, and the scanning speed can reach 1 m/s or even higher. It is widely used in various products. Forming machine.

The scanning mechanism of the galvanometer widely adopts a fixed working mode, in which the mechanical deflection angle of the scanning motor is limited, generally within ±20°, and the mirror is bonded to the rotating shaft of the scanning motor, and the rotation of the scanning motor drives the deflection of the mirror to realize the laser The deflection of the beam, the scanning area is limited, and because the forming process requires the laser energy, good forming can only be done within a certain scanning range, and the forming space is limited. The 1.2×1.2m worktable SLS equipment developed by the research group of the Rapid Manufacturing Center of Huazhong University of Science and Technology is the world's largest worktable single-galvanometer scanning mechanism rapid prototyping system, which can be used for wax mold and sand mold (core) manufacturing; foreign German EOS company's The working surface of EOSINT P 800 equipment is 730×380×540mm, which can be used for the manufacture of metal and ceramic parts. These devices are currently the world's newest rapid prototyping systems for large-table single-galvanometer mirrors, but it is still difficult to meet the manufacturing needs of larger-sized parts.

The multi-galvanometer scanning mechanism is used to realize the cooperative work of multiple energy beams, and the forming table can be enlarged through the synergistic superposition effect of multiple forming areas. The double-galvanometer scanning mechanism SLS rapid prototyping system developed by the Rapid Manufacturing Center of Huazhong University of Science and Technology expands the working surface to 1.4×0.7m. However, the core optics galvanometer laser scanning system is a high-tech and expensive part of rapid prototyping equipment. On the one hand, the use of multi-galvanometer scanning mechanism greatly increases the hardware cost, on the other hand, it also increases the complexity of hardware control, software technology and other links, which reduces the stability of the system to a certain extent and limits the application of this technology in large-scale manufacturing. Application of dimensionally complex part orientation.

Contents of the invention

The invention provides a mobile vibrating mirror device, which overcomes the shortage of limited forming space in the fixed working mode of the existing vibrating mirror scanning mechanism, and at the same time avoids the problem of increasing hardware cost and complexity by adopting a multi-vibrating mirror scanning mechanism.

A mobile galvanometer device of the present invention includes a bottom plate, a guide rail, a beam, an X-direction synchronous belt, an X-direction synchronous pulley, and an X-direction servo motor. A rectangular window is opened in the middle of the bottom plate, and two guide rails are fixed parallel to the rectangular window. On a pair of opposite sides of the window, an X-direction synchronous pulley and an X-direction servo motor are fixed next to a guide rail on the bottom plate. The beam is perpendicular to the guide rail, the beam is slidably matched with the two guide rails through the X-direction slider, and one end of the beam is fixed on the X-direction timing belt; it is characterized in that:

There is a galvanometer scanning mechanism on the beam, and the galvanometer scanning mechanism includes an α mirror, a β mirror, an α scanning motor, a β scanning motor and a servo drive unit, and the spatial directions of the rotating shafts of the α and β scanning motors are orthogonal to each other. The α and β mirrors are bonded to the rotating shafts of the α and β scanning motors respectively, and the servo drive unit receives instructions to drive the α and β scanning motors.

The mobile galvanometer device is characterized in that:

A Y-direction synchronous pulley and a Y-direction servo motor are fixed on the beam, and the Y-direction synchronous belt is parallel to the beam, and is tensioned by the Y-direction synchronous pulley and the Y-direction servo motor shaft. The block is slidingly matched with the beam, and one end of the Y-direction slider is fixed on the Y-direction synchronous belt.

The invention fixes the vibrating mirror scanning mechanism on the beam, drives the beam to move along the direction of the guide rail through the X-direction servo motor, thereby realizing the precise movement of the vibrating mirror scanning mechanism in the X direction of the forming plane; furthermore, the Y-direction slider and the Y-direction slider can be installed on the beam Y-direction servo motor, fix the vibrating mirror scanning mechanism on the Y-direction slider, control the rotation of the Y-direction servo motor through software, realize the movement of the vibrating mirror scanning mechanism along the beam, and realize precise movement in the XY direction of the forming plane.

The galvanometer rapid prototyping system processes parts based on slice information. First, the scanning range of the galvanometer is set by software. In order to simplify the scanning process, the scanning range is set to a square. When the outline size of the slice does not exceed the scanning range, the galvanometer scanning mechanism does not move, and directly processes according to the slice information; when the outline size of the slice exceeds the scanning range, the slice is divided into several areas, and the galvanometer scanning mechanism moves sequentially Go above the center of these areas, and scan the next area after one area is scanned. Finally, after one layer is processed, the galvanometer scanning mechanism returns to its original position, and the next layer is processed according to the previous settings until the entire part is processed.

In the present invention, the X-direction servo motor or the X-direction and Y-direction servo motors drive the overall movement of the vibrating mirror scanning mechanism, which can realize the precise movement of the vibrating mirror scanning mechanism in the XY direction, and flexibly and variablely determine the vibrating mirror according to the specific size information of the parts. The moving distance of the scanning mechanism; compared with the existing fixed galvanometer scanning mechanism, the forming space is expanded, and the same forming space as multiple fixed galvanometer scanning mechanisms can be achieved, reducing hardware costs, and its control, software, and process advantages The complexity is close to that of a single fixed galvanometer scanning mechanism, which reduces the cost and complexity of manufacturing large-scale and complex parts; it is suitable for mass production of large-size parts.

Description of drawings

Fig. 1 is the three-dimensional schematic diagram of embodiment 1 of the present invention;

Fig. 2 is the top view of embodiment 1 of the present invention;

Fig. 3 is a schematic diagram of the vibrating mirror scanning mechanism;

Figure 4 is a schematic diagram of the entity of complex box parts;

Figure 5 is a schematic diagram of the 300mm height section slice information and processing partition of complex box parts;

Fig. 6 is the top view of embodiment 2 of the present invention;

Fig. 7 is a schematic diagram of turbine disc parts;

Fig. 8 is a schematic diagram of section slice information and processing partitions of a turbine disk part at a height of 150mm.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

As shown in Figures 1 and 2, Embodiment 1 of the present invention includes a bottom plate 7, a guide rail 5, a beam 2, an X-direction synchronous belt 3, an X-direction synchronous pulley 1 and an X-direction servo motor 4, and the middle part of the bottom plate 7 is opened. There is a rectangular window, and two guide rails 5 are fixed on a pair of opposite sides of the rectangular window in parallel, and an X-direction synchronous pulley 1 and an X-direction servo motor 4 are fixed next to a guide rail on the bottom plate 7, and the X-direction synchronous belt 3 is parallel to the guide rail 5 , is tensioned by the X-direction synchronous pulley 1 and the X-direction servo motor shaft, the crossbeam 2 is perpendicular to the guide rail 5, the crossbeam 2 slides with the two guide rails through the X-direction slider 8, and one end of the crossbeam 2 is fixed on the X-direction timing belt 3; the beam 2 is fixed with a vibrating mirror scanning mechanism 6 .

The servo motor 4 rotates under software control, driving the synchronous pulley to rotate, the synchronous belt 3 moves together with the pulley, and the crossbeam 2 is fixed with the synchronous belt 3 through screws, so driven by the synchronous belt, it moves along the guide rail 5 to realize vibration Movement of the mirror scanning mechanism in the X direction. In this way, the galvanometer scanning mechanism can move in a single direction, which is suitable for processing parts with a relatively large aspect ratio.

As shown in Figure 3, the galvanometer scanning mechanism 6 includes an α reflector 10, a β reflector 12, an α scan motor 9, a β scan motor 11 and a servo drive unit, and the spatial directions of the rotating shafts of the α and β scan motors are mutually orthogonal, The α and β mirrors are bonded to the rotating shafts of the α and β scanning motors respectively, and the servo drive unit receives instructions to drive the α and β scanning motors. The α scanning motor 9 and the β scanning motor 11 rotate in coordination, driving and connecting them on their rotating shafts. The α-mirror lens 10 and the β-mirror lens 12 reflect the laser light to realize graphic scanning on the working surface. In Embodiments 1 and 2 of the present invention, the POWERSCAN33 vibrating mirror scanning mechanism of the German SCANLAB company is directly used.

As shown in Figure 4, the outline size of the complex box part to be processed is 1290.0×416.94×1032.33mm. The processing range of the existing rapid prototyping equipment for metal processing is 450mm, and this part cannot be processed at one time by using the fixed vibrating mirror rapid prototyping system. According to the structure of the parts and the parameters of the processing technology, Embodiment 1 can be used for processing and manufacturing. The slicing graphics and processing partitions of the part at a height of 300 mm are shown in Figure 5.

(1) The rapid prototyping software reads in the STL file of the part, sets the processing area as a square area of 450×450mm, and sets other processing parameters. As shown in Figure 7, according to the outline range of the slice, it is divided into regions V ₁ , V ₂ and V ₃ , and their centers are O ₁ , O ₂ and O ₃ respectively. According to the slice information and processing technology of V ₁ , V ₂ and V ₃ , the scanning actions of the galvanometer scanning mechanism are determined as S ₁ , S ₂ and S ₃ . Therefore, the movement of the whole galvanometer scanning mechanism is a series of movements of (O ₁ , S ₁ ), (O ₂ , S ₂ ), (O ₃ , S ₃ ).

(2) Read the coordinates (X ₁ , Y ₀ ), (X ₂ , Y ₀ ), (X ₃ , Y ₀ ) of O ₁ , O ₂ , O ₃ , the control system controls the movement of the servo motor in the X direction, and the vibration The mirror scanning mechanism moves to O ₁ along the X direction, and runs according to the determined scanning action S ₁ . After the area _V1 is scanned, the galvanometer scanning mechanism moves to O ₂ along the X direction, runs according to the determined scanning action S ₂ , and completes the scanning of the area V ₂ . According to the same process, the scanning of the area _V3 is completed, so that the processing of one slice is completed.

(3) The galvanometer scanning mechanism returns to the initial position O ₀ , reads the slice information of the next layer, repeats the actions described in (1) and (2) above, and completes the processing of the next layer. Reciprocate in this way until all layers are processed, and one processing is completed.

As shown in Figure 6, Embodiment 2 of the present invention includes base plate 7, guide rail 5, beam 2, X-direction synchronous belt 3, X-direction synchronous pulley 1 and X-direction servo motor 4, and Y-direction synchronous belt is fixed on the beam 2 Wheel 16 and Y-direction servo motor 14, Y-direction synchronous belt 15 is parallel to crossbeam 2, tensioned by Y-direction synchronous pulley and Y-direction servo motor shaft, described galvanometer scanning mechanism 6 slides with crossbeam through Y-direction slide block 13 Cooperate, one end of Y to slide block 13 is fixed on the Y to synchronous belt.

As shown in Figure 7, the outline size of the turbine disk part to be processed is 1213.50×1275.36×361.17mm. The processing range of the existing rapid prototyping equipment for processing metal is 450 mm, which can be processed and manufactured through Embodiment 2. The slicing graphics and processing partitions of the part at a height of 150 mm are shown in Figure 8.

Divide the original large-size forming surface into several areas, move the galvanometer scanning mechanism to the center of the corresponding area through the control system and mechanical structure, and form these areas separately, and finally obtain a large-size area. The specific processing process of Example 2 for:

(1) The rapid prototyping software reads in the STL file of the part, and then determines the square area of a single scanning area with a size of 450×450 mm according to the formable range of the galvanometer scanning mechanism. According to the outline range of the slice, it can be divided into areas V ₁ , V ₂ , ..., V ₈ , and their centers are O ₁ , O ₂ , ..., O ₈ , respectively. The scanning actions of the galvanometer scanning mechanism are determined as S ₁ , S ₂ , . . . , S ₈ according to the slice information and processing technology of each partition. Therefore, the movement of the whole galvanometer scanning mechanism is a series of movements of (O ₁ , S ₁ ), (O ₂ , S ₂ ), . . . , (O ₈ , S ₈ ).

(2) After the scanning action is determined, the software controls the X-direction and Y-direction servo motors and the galvanometer scanning mechanism according to the information of (O ₁ , S ₁ ), (O ₂ , S ₂ ), ..., ( _On , S _n ) Actions. First, the software reads the coordinate data (X ₁ , Y ₁ ) of O ₁ , controls the movement of the X-direction servo motor installed on the guide rail, and drives the beam along the guide rail to the X ₁ position through the transmission of the X-direction synchronous belt, and then installs it on the The Y-direction servo motor on the crossbeam moves and is driven by the Y-direction synchronous belt to move the vibrating mirror scanning mechanism to the Y1 position. When the vibrating mirror scanning mechanism moves to the position _O1 , it starts to scan according to the slice information of the corresponding area _V1 , and the action of the vibrating mirror scanning mechanism is _S1 . When the S ₁ action ends, the software controls the X-direction and Y-direction servo motor movement to realize the movement of the galvanometer scanning mechanism from O ₁ to O ₂ , and the galvanometer scanning mechanism starts to scan according to the slice information in this area V ₂ , and the galvanometer scan mechanism The scanning mechanism performs action S ₂ . Then, the X-direction and Y-direction servo motors and the galvanometer scanning mechanism are controlled by software to realize the moving and scanning process from (O ₃ , S ₃ ) to (O ₈ , S ₈ ). In this way, the scanning process of one slice is completed.

(3) The galvanometer scanning mechanism returns to the original position O ₀ , reads the slice information of the next layer, repeats the actions described in (1) and (2) above, and completes the processing of the next layer, and so on, until all layers are processed, In this way, the processing is completed once.

Claims (2)

1. portable galvanometer device; Comprise base plate, guide rail, crossbeam, X to synchronous band, X to synchronous pulley and X to servomotor, said base plate middle part has rectangular window, two guide rail secured in parallel are on a pair of opposite side of rectangular window; On the base plate guide rail next door be fixed with X to synchronous pulley and X to servomotor; X is parallel with guide rail to synchronous band, by X to synchronous pulley and X to the servo motor shaft tensioning, said crossbeam is vertical with guide rail; Crossbeam is slidingly matched to slide block and two guide rails through X, and crossbeam one end is fixed on X to being with synchronously; It is characterized in that:

Has vibration mirror scanning mechanism on the said crossbeam; Said vibration mirror scanning mechanism comprises α speculum, β speculum, α scan module, β scan module and servo drive unit; The rotating shaft direction in space mutually orthogonal of α, β scan module; α, β speculum are bonded in respectively in the rotating shaft of α, β scan module, and servo drive unit is accepted instruction, drive α, β scan module.

2. portable galvanometer device as claimed in claim 1 is characterized in that:

Be fixed with on the said crossbeam Y to synchronous pulley and Y to servomotor; Y is parallel with crossbeam to synchronous band; By Y to synchronous pulley and Y to the servo motor shaft tensioning, said vibration mirror scanning mechanism is slidingly matched to slide block and crossbeam through Y, Y is fixed on Y to being with synchronously to slide block one end.

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