CN210415528U

CN210415528U - Digital light processing 3D printing device based on nonlinear focusing multi-partition exposure

Info

Publication number: CN210415528U
Application number: CN201920747882.6U
Authority: CN
Inventors: 宋长辉; 刘子彬; 邓正泰; 李蔚东; 唐郁滔
Original assignee: South China University of Technology SCUT
Current assignee: South China University of Technology SCUT
Priority date: 2019-05-22
Filing date: 2019-05-22
Publication date: 2020-04-28
Anticipated expiration: 2029-05-22

Abstract

The utility model discloses a digital light processing 3D printing device based on exposure of multiple subregion of nonlinear focusing, the device regard as electronic focusing system at DLP projecting apparatus focusing light ring side-mounting step-by-step servo motor and planetary reducer to the hold-in range zooms as transmission control projecting apparatus light ring accuracy. And the control main board controls the multi-exposure curing of the DLP projector in different areas. The device realizes the purposes of changing the focus of a light source and uniformly curing during exposure and curing by additionally arranging a high-resolution electric focusing mechanism. Meanwhile, the device can achieve the purposes of reducing shrinkage and improving the edge strength of parts by nonlinear focusing multi-partition exposure during curing, thereby improving the molding quality. The utility model discloses mainly relate to the multiple exposure intelligence 3D printer of vibration material disk, especially have the projecting apparatus and the multiple exposure function of subregion that can zoom in succession automatically.

Description

Digital light processing 3D printing device based on nonlinear focusing multi-partition exposure

Technical Field

The utility model belongs to the technical field of increase material manufacturing (3D prints), concretely relates to digital light processing 3D printing device based on multiple subregion of nonlinear focusing exposes to sun.

Background

With the development of additive technology, many scholars and engineers further research on printing methods, printing equipment and printing materials, and the development of industrial production is promoted. Taking the antenna housing applied in the field of aerospace as an example, the structure of the antenna housing mostly adopts an interlayer structure, the outer layer is a thin compact surface layer, the rain erosion resistance and the ablation resistance can be ensured, the core layer has higher porosity, low dielectric constant and reliable mechanical property, and the high wave transmittance of a broadband can be realized in a microwave or millimeter wave band while the core layer has good mechanical property and dielectric property. Although the conventional injection molding, injection-coagulation molding, filter-press molding, pressure molding, gel molding, cutting and other manufacturing processes are well-established, these technologies cannot realize the fabrication of such a sandwich structure. Products with obvious individuation, refinement, light weight or complicated requirements under similar conditions cannot be processed by the traditional manufacturing process. Therefore, the development of new ceramic forming technology becomes a key for breaking through the bottleneck of product application.

The most mature and widely applied FDM, and the selective laser sintering SLS and the digital light curing DLP are the more material-oriented additive technologies. The DLP projector adopted by the DLP 3D printing equipment needs to be started and closed at high frequency in the exposure forming process, and the projector bulb and the circuit need large current and high voltage to realize preheating operation at short time and high frequency, so that the service life of the projector bulb is short and the precision of the projector is reduced. When the bulb is replaced, the DLP projector is easy to damage, and a special measuring instrument is needed for adjustment and correction. And traditional formula 3D printer of shining down is because the projecting apparatus is put down, so the light intensity is not enough, focus location is inaccurate and can only fix a certain height can appear after the light source process silo bottom plate with from the type membrane, thereby can lead to phenomenon such as solidification inhomogeneous to influence the part shaping precision in the part shaping process. In addition, general digital light curing molding 3D printing apparatus can only once whole section image when the solidification, can appear sticking up the limit when solidification molding large tracts of land part, and the shrink is obvious, the not high scheduling problem of product edge solidification precision.

SUMMERY OF THE UTILITY MODEL

The utility model discloses a main aim at overcomes prior art's shortcoming and not enough, provides a digital light processing 3D printing device of multiple subregion of nonlinear focusing exposure, thereby can the multiple subregion of nonlinear focusing expose when the solidification to reduce shrink, improve part edge strength and improve shaping quality purpose.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

the utility model discloses a digital light processing 3D printing device based on exposure of nonlinear focusing multiple subregion, including projecting apparatus, scraper, storage vat, stone actuating system mount, X axle linear guide, servo motor, round brush, print platform, pressure flitch, square steel frame, the focusing motor of electronic focusing system, planetary reducer, motor holder, projecting apparatus fore-stock, X axle step motor, ball screw mechanism, Z axle bearing plate, servo motor holder, L type pole, grating chi connecting plate, projecting apparatus after-poppet, projecting apparatus support connecting piece, monofilament pole nut pair link span, grating chi connecting block, grating chi reading head, reading head mount, trough of belt concave type scraper connecting block and Z axle linear guide, the projecting apparatus passes through the ultraviolet ray material curing moulding on the print platform, Z axle bearing plate machinery is connected and is fixed in the square steel frame, the printing platform is mechanically connected with a Z-axis linear guide rail, and the Z-axis linear guide rail is mechanically connected with a ball screw mechanism;

the printing platform, the Z-axis linear guide rail and the ball screw mechanism form a Z axis, the servo motor retainer is mechanically connected with the servo motor, and the Z-axis linear guide rail and the servo motor retainer are arranged on the Z-axis bearing plate; the grating ruler is mechanically connected with the grating ruler connecting block, and the grating ruler reading head is mechanically connected with the reading head fixing frame; the X-axis linear guide rail is fixed on a paving driving system fixing frame, the X-axis stepping motor is fixed on the paving driving system fixing frame, the rolling brush and the paving driving system fixing frame form a rotating pair through a small hole, the scraper is mechanically connected with the groove concave scraper connecting block, one end of the L-shaped rod is mechanically connected with the groove concave scraper connecting block, and the other end of the L-shaped rod is mechanically connected with a sliding block on the X-axis linear guide rail;

the X-axis linear guide rail, the paving driving system fixing frame, the X-axis stepping motor, the scraper, the grooved concave scraper connecting block and the L-shaped rod jointly form movement in the X-axis direction; the projector is fixed in the projector fore-stock, and the projector fore-stock passes through projector support connecting piece and two pairs of bolt-nut mechanical connection with the projector after-poppet, and the projector fore-stock leans on two suddenly boards with the square steel frame contact with it mechanical connection with the projector after-poppet, the focusing motor of electronic focusing is installed at the planetary reducer input, and planetary reducer passes through the motor holder and installs on the projector after-poppet to realize the control to projector focusing light ring through the transmission of hold-in range, thereby the projector carries out multiple subregion exposure to the section image according to section image area and required precision when the exposure solidification and realizes the regional solidification, and the round brush plays the cleaning action through the frictional action with the scraper.

As a preferred technical scheme, the printing platform is mechanically connected with the Z-axis linear guide rail through a single lead screw nut pair connecting frame; and the Z-axis linear guide rail is mechanically connected with the ball screw mechanism through a single screw nut pair connecting frame.

According to a preferable technical scheme, the servo motor is connected with the ball screw mechanism through a coupler, and the Z-axis movement is controlled through the servo motor.

According to the preferable technical scheme, the grating ruler is mechanically connected with the grating ruler connecting block through the grating ruler connecting plate, and the grating ruler reading head is mechanically connected with the reading head fixing frame and fastened on the Z-axis supporting plate through threads to form the position feedback system.

Preferably, the X-axis linear guide is configured as a double X-axis linear guide, the double X-axis linear guide is disposed in parallel, and the Z-axis linear guide is configured as a double Z-axis linear guide, the double Z-axis linear guide is disposed in parallel.

As the preferred technical scheme, the projector is fixed on the front bracket of the projector through the threaded connection of 3 hoisting threaded holes on the surface of the projector and bolts.

As a preferable technical scheme, the focusing motor is installed at a power input end of a planetary reducer matched with the focusing motor, and the planetary reducer is installed at a position, close to a projector lens, of a rear support of the projector through a motor retainer.

As a preferable technical scheme, the focusing motor stably and accurately rotates after receiving the command of the control main board, and angular displacement of the focusing motor is further subdivided by the planetary reducer and then transmitted to the synchronizing wheel.

As a preferable technical scheme, the focusing aperture is connected with a synchronous wheel on a planetary reducer through a synchronous belt, and the planetary reducer further subdivides the rotary motion of a focusing motor to drive the focusing aperture to rotate so as to realize the movement of the focus of the curing light source.

Compared with the prior art, the utility model, following advantage and beneficial effect have:

(1) the utility model discloses a step-by-step servo motor refines the purpose of fine setting projecting apparatus light ring in order to reach automatic zoom exposure, even solidification behind the step angle through planetary reducer, simultaneously the utility model discloses a divide regional successively multiple exposure with a slice image according to shaping area and required precision, reach the purpose that reduces shrink, optimize the edge and improve part edge hardness.

(2) The utility model can accurately move the curing light source focus receiving control main board through the electric focusing system, so that the molding material can be uniformly irradiated and exposed in a zooming way by the curing light source focus in the exposure curing process, thereby achieving the effect of being uniformly cured in each layer thickness; the curing mode avoids the problem that similar DLP 3D printing equipment can only fix the projection focus on the upper surface of a printing material, but materials below the upper surface cannot ensure the consistent curing quality of the materials in one layer thickness due to insufficient curing light intensity and the influence of a curing sequence, and further improves the forming quality of a printed piece in the Z-axis direction;

(3) the utility model discloses printing material different regions can be separately exposed solidification, multiple exposure in individual layer solidification process, utilizes the outward flange solidification earlier, and the exposure order of solidification is strengthened to whole face at last to inside postcure, reaches and improves marginal shaping quality, reduces the beneficial effect who sticks up the limit.

(4) The utility model discloses DLP projector light source is through adjusting the projector light intensity in whole exposure curing forming process, weakens and keeps the projector light intensity to another solidified layer exposure curing beginning period at a solidified layer exposure curing completion promptly, thereby avoids the projector bulb to receive heavy current, high voltage to preheat because of frequently opening and closing and constantly having improved projector utility life, reduction equipment later maintenance cost and improve equipment stability.

Drawings

Fig. 1 is an isometric view of the 3D printing apparatus of the present invention;

FIG. 2 shows the sectional continuous multiple exposure forming system of the present invention;

FIG. 3 is a flow chart of the single-layer partitioned continuous multiple exposure curing process of the present invention;

fig. 4 is a perspective view of the projector mount body of the present invention;

fig. 5 is a side view of the projector assembly of the present invention;

FIG. 6 is an axial view of the ceramic seal ring of the present invention;

FIG. 7 is a schematic view of the sectional multiple exposure process of the present invention;

FIG. 8 is a flow chart of the automatic zooming of the present invention;

fig. 9 is a front view of the Z-axis closed-loop control moving system of the present invention.

The reference numbers illustrate:

the system comprises a projector, a scraper, a storage cylinder, a paving driving system fixing frame, an X-axis linear guide rail, a servo motor, a rolling brush, a printing platform, a material pressing plate, a square steel frame, a focusing motor, a planetary speed reducer, a motor retainer, a projector front support, an X-axis stepping motor, a ball screw mechanism, a Z-axis supporting plate, a servo motor retainer, an L-shaped rod, a grating ruler connecting plate, a projector rear support, a projector support connecting piece, a single-screw rod nut pair connecting frame, a grating ruler connecting block, a grating ruler reading head, a reading head fixing frame, a groove scraper connecting block and a Z-axis linear guide rail, wherein the projector front support is 14, the X-axis stepping motor is 15, the ball screw rod mechanism is 16, the Z-axis supporting plate is 17, the servo motor retainer is 18, the L.

Detailed Description

The present invention will be described in further detail with reference to the following examples and drawings, but the present invention is not limited thereto.

Examples

As shown in fig. 1, the utility model relates to a digital light processing 3D printing device based on divide regional continuous multiple exposure, including projecting apparatus 1, scraper 2, storage vat 3, stone actuating system mount 4, X axle linear guide 5, servo motor 6, round brush 7, print platform 8, pressure flitch 9, square steel frame 10, focusing motor 11, planetary reducer 12, motor holder 13, projecting apparatus front bracket 14, X axle step motor 15, ball screw mechanism 16, Z axle supporting plate 17, servo motor holder 18, L type pole 19, grating chi connecting plate 20, projecting apparatus rear bracket 21, projecting apparatus support connecting piece 22, monofilament pole nut auxiliary connecting frame 23, grating chi 21, grating chi connecting block 25, grating chi reading head 26, reading head mount 27, concave type scraper connecting block 28 and Z axle linear guide 29; the X-axis linear guide 5 is configured as a double X-axis linear guide, and the double X-axis linear guides are arranged in parallel, and the Z-axis linear guide 29 is configured as a double Z-axis linear guide, and the double Z-axis linear guides are arranged in parallel. The projector 1 solidifies and forms materials on a printing platform 8 through ultraviolet light, a Z-axis supporting plate 17 is mechanically connected and fixed on a square steel frame 10, the printing platform 8 is mechanically connected with a Z-axis linear guide rail 29 through a single screw nut pair connecting frame 23, the parallel Z-axis linear guide rail 29 is mechanically connected with a ball screw cylinder mechanism 16 through the single screw nut pair connecting frame 23, the printing platform 8, the single screw nut pair connecting frame 23, the Z-axis linear guide rail 29 and the ball screw mechanism 16 form a Z-axis motion system, a servo motor holder 18 is mechanically connected with a servo motor 6, the Z-axis linear guide rail and the servo motor holder 18 are arranged on the Z-axis supporting plate 17 through screw nuts (as shown in figure 9), the servo motor 6 is connected with the ball screw mechanism 16 through a coupler, Z-axis motion is formed through the control of the servo motor 6, a grating scale 24 is mechanically connected with a grating scale connecting block 25 through a grating scale connecting plate, the grating ruler reading head 26 is mechanically connected with a reading head fixing frame 27 and is fastened on the Z-axis supporting plate 17 through threads to form a position feedback system; the two parallel X-axis linear guide rails 5 are fixed on a paving driving system fixing frame 4, an X-axis stepping motor 15 is fixed on a paving driving system fixing frame 14, a rolling brush 7 forms a revolute pair in the paving driving system fixing frame 4 through a small hole, a scraper 2 is mechanically connected with a groove-shaped concave scraper connecting block 28 and can adjust levelness through an adjusting spring between the scraper and the groove-shaped concave scraper connecting block 28, an L-shaped rod 19 is mechanically connected with the groove-shaped concave scraper connecting block 28, the L-shaped rod 19 is mechanically connected with a sliding block on the X-axis linear guide rails 5, and the parallel X-axis linear guide rails 5, the paving driving system fixing frame 4, the X-axis stepping motor 15, the scraper 2, the groove-shaped concave scraper connecting block 28 and the L-; the projector 1 is fixed on a projector front support 14 through the threaded connection of 3 hoisting threaded holes and bolts on the surface of the projector 1, the projector front support 14 and a projector rear support 21 are mechanically connected with two pairs of bolt nuts through a projector support connecting piece 22 (as shown in figure 4), the projector front support 14 and the projector rear support 21 are mechanically connected with each other through two convex plates in contact with a square steel frame 10, an electric projector assembly body with an electric focusing system and a Z-axis moving mechanism form a nonlinear focusing multi-partition exposure system (as shown in figure 2), a material storage cylinder 3 is mechanically connected with the material storage cylinder through two convex plates in contact with the square steel frame 10, the focusing motor 11 of the electric focusing system is mechanically connected with the power input end of a planetary reducer 12, the planetary reducer 12 is installed on the projector rear support 21 through a motor retainer 13, and the control of the focusing aperture of the projector 1 is realized through the transmission of a synchronous belt (as shown in figure 5).

The focusing motor adopts the step servo motor with high positioning accuracy and high static torque to be installed at the power input end of the planetary reducer through the motor retainer, the planetary reducer is mechanically installed at one side close to a DLP projector focusing aperture through the motor retainer, the focusing aperture is connected with the output end of the planetary reducer through a synchronous belt and a synchronous wheel device, the step servo motor can stably and accurately rotate after receiving a pulse signal of the control main board, the angular displacement of the step servo motor is further subdivided through the planetary reducer and then transmitted to the projector focusing aperture, and therefore the purpose of automatically finely adjusting the focal length of the control main board during exposure curing is achieved.

When the DLP projector is used for exposing and curing the molding material, different areas of the slice image are sequentially cured according to the area and precision requirements of the slice image during exposure and curing, and the nonlinear multi-partition exposure flow curing process is as shown in figure 3, namely, the problems of obvious shrinkage, serious edge warping and the like of the molding material due to large molding area during exposure are avoided by exposing each slice in a multi-partition mode.

DLP projecting apparatus is when exposure solidification molding material, through adjusting the projecting apparatus light intensity, strengthens the projecting apparatus light intensity when exposure solidification material promptly, and weakens and keeps the projecting apparatus light intensity when a solidified layer exposure solidification finishes to another solidified layer exposure solidification beginning period, thereby avoids the projecting apparatus bulb to receive heavy current, high voltage to preheat because of frequently opening and closing and constantly, thereby reach the purpose that improves projecting apparatus practical life, reduction equipment later maintenance cost and improve equipment stability.

Before printing, a digital model can be designed by CAD software such as solidworks, UG and the like according to the use requirements, the digital model is stored as a file of STL suffix, the file is imported into slicing software such as creative work shop and the like, parameters such as multiple exposure curing sequence, slicing layer thickness, printing speed, platform safety height, scraper speed and the like are set, and then slicing processing is carried out. The printing code generated after slicing can be connected with the printer control mainboard for printing.

Further, during printing, resin and the like are used as carriers to contain solid powder to form a printing material with certain fluidity, the printing material is stored in the storage cylinder 3 before printing, when the material is paved in the printing process, the groove concave scraper connecting block 28 of the scraper 2 is dragged by the X-axis stepping motor 15 due to the fact that the L-shaped rod 19 is connected with the sliding block driven by the synchronous belt, the liquid material is paved on the printing platform by moving towards the direction close to the X-axis stepping motor from the position far away from the X-axis stepping motor, then the scraper scrapes the printing material through the printing platform reversely, paving and scraping of the printing material are completed, and after the scraper returns, the projector 1 performs regional sequential exposure on the printing material on the printing platform according to image data of slice software.

Take a printing and forming process of a ceramic seal ring (as shown in fig. 4) as an example. The inner and outer edges of the device have high precision requirement due to assembly requirement, cannot accept the defects of edge warping, serious shrinkage and the like, and the partitioned multiple exposure process is shown in fig. 5. Specifically, when each image area is exposed and cured, a stepping servo motor with high positioning accuracy and high static torque stably and accurately rotates after receiving a pulse signal of a control main board, the angular displacement of the stepping servo motor is further subdivided by a stepping speed reducer and then is connected with a focusing aperture of the projector through a synchronous belt and a synchronous wheel device, and an electric focusing system drives the focusing aperture to rotate after receiving the pulse signal of the control main board, so that the movement of a curing light source focus is realized. Taking exposure curing of a certain layer of the ceramic sealing ring as an example, when curing a layer of printing material, the flow of multi-exposure curing in different areas is shown in fig. 3, the sequence of multi-exposure curing in different areas is shown in fig. 7, the leftmost is an original figure, and the processes of exposure curing edge, exposure filling inside and overall enhanced exposure are sequentially performed; the relationship between the displacement of the focus of the curing light source in the Z-axis direction and the time is shown in FIG. 8, the left part in FIG. 8 is a schematic diagram of the formed zero-monolayer slice, and the right part is a schematic diagram of the height of the focus of the light source and the exposure time. After the layer of printing material is cured, on the Z axis, the Z axis motion system mechanically connected with the printing platform 8 realizes the downward movement of the printing platform through the closed-loop control of the servo motor 6, so as to provide a space for the spreading of the next layer of printing material, and the period of one printing layer thickness is finished.

The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be equivalent replacement modes, and all are included in the scope of the present invention.

Claims

1. Digital light processing 3D printing device based on nonlinear focusing multi-partition exposure, which is characterized by comprising a projector (1), a scraper (2), a storage cylinder (3), a paving driving system fixing frame (4), an X-axis linear guide rail (5), a servo motor (6), a rolling brush (7), a printing platform (8), a material pressing plate (9), a square steel frame (10), a focusing motor (11) of an electric focusing system, a planetary reducer (12), a motor retainer (13), a projector front support (14), an X-axis stepping motor (15), a ball screw mechanism (16), a Z-axis bearing plate (17), a servo motor retainer (18), an L-shaped rod (19), a grating ruler connecting plate (20), a projector rear support (21), a projector support connecting piece (22), a single-wire rod nut pair connecting frame (23), a grating ruler (24), The optical grating scale printing device comprises a grating scale connecting block (25), a grating scale reading head (26), a reading head fixing frame (27), a groove concave scraper connecting block (28) and a Z-axis linear guide rail (29), wherein the projector (1) solidifies and molds materials on a printing platform (8) through ultraviolet light, a Z-axis supporting plate (17) is mechanically connected and fixed to a square steel frame (10), the printing platform (8) is mechanically connected with an X-axis linear guide rail (5), and the Z-axis linear guide rail (29) is mechanically connected with a ball screw mechanism (16);

the printing platform (8), the Z-axis linear guide rail (29) and the ball screw mechanism (16) form a Z axis, the servo motor retainer (18) is mechanically connected with the servo motor (6), and the Z-axis linear guide rail (29) and the servo motor retainer (18) are arranged on a Z-axis bearing plate (17); the grating ruler (24) is mechanically connected with the grating ruler connecting block (25), and the grating ruler reading head (26) is mechanically connected with the reading head fixing frame (27); the X-axis linear guide rail (5) is fixed on the paving driving system fixing frame (4), the X-axis stepping motor (15) is fixed on the paving driving system fixing frame (4), the rolling brush (7) and the paving driving system fixing frame (4) form a rotating pair through a small hole, the scraper (2) is mechanically connected with the groove-grooved concave scraper connecting block (28), one end of the L-shaped rod (19) is mechanically connected with the groove-grooved concave scraper connecting block (28), and the other end of the L-shaped rod is mechanically connected with a sliding block on the X-axis linear guide rail (5);

the X-axis linear guide rail (5), the paving driving system fixing frame (4), the X-axis stepping motor (15), the scraper (2), the grooved concave scraper connecting block (28) and the L-shaped rod (19) jointly form movement in the X-axis direction; the projector (1) is fixed on a projector front support (14), the projector front support (14) and a projector rear support (21) are mechanically connected with two pairs of bolts and nuts through a projector support connecting piece (22), the projector front support (14) and the projector rear support (21) are mechanically connected with the projector front support and the projector rear support by two convex plates which are in contact with a square steel frame (10), a focusing motor (11) of the electric focusing system is arranged at the input end of a planetary reducer (12), the planetary reducer (12) is arranged on a rear bracket (21) of the projector through a motor retainer (13), the control of a focusing aperture of the projector (1) is realized through the transmission of a synchronous belt, the projector (1) performs multi-partition exposure on a slice image according to the area and precision requirements of the slice image during exposure and curing so as to realize partition curing, and the rolling brush (7) plays a cleaning role through the friction action with the scraper (2).

2. The digital light processing 3D printing device based on nonlinear focusing multiple-partition exposure is characterized in that the printing platform (8) is mechanically connected with a Z-axis linear guide rail (29) through a single-screw nut pair connecting frame (23); the Z-axis linear guide rail (29) is mechanically connected with the ball screw mechanism (16) through a single screw nut pair connecting frame (23).

3. The digital light processing 3D printing device based on nonlinear focusing multi-partition exposure is characterized in that the servo motor (6) is connected with a ball screw mechanism (16) through a coupler, and the Z-axis movement is controlled through the servo motor (6).

4. The digital light processing 3D printing device based on nonlinear focusing multiple-partition exposure is characterized in that the grating scale (24) is mechanically connected with a grating scale connecting block (25) through a grating scale connecting plate (20), and a grating scale reading head (26) is mechanically connected with a reading head fixing frame (27) and is fastened on a Z-axis supporting plate (17) through threads to form a position feedback system.

5. The digital light processing 3D printing apparatus based on nonlinear focusing multi-division exposure according to claim 1, wherein the X-axis linear guide (5) is configured as a dual X-axis linear guide and the dual X-axis linear guide is arranged in parallel, and the Z-axis linear guide (29) is configured as a dual Z-axis linear guide and the dual Z-axis linear guide is arranged in parallel.

6. The digital light processing 3D printing device based on nonlinear focusing multi-partition exposure is characterized in that the projector (1) is fixed on the front projector bracket (14) through the threaded connection of 3 hoisting threaded holes and bolts on the surface of the projector.

7. The digital light processing 3D printing device based on nonlinear focusing multiple-partition exposure is characterized in that the focusing motor (11) is installed at the power input end of a planetary reducer (12) matched with the focusing motor, and the planetary reducer (12) is installed at the position, close to the projector lens, of the rear support of the projector through a motor holder (13).

8. The digital light processing 3D printing device based on nonlinear focusing multiple-partition exposure is characterized in that the focusing motor (11) is smoothly and accurately rotated after receiving a command of a control main board, and the angular displacement is further subdivided by a planetary reducer and then transmitted to a synchronous wheel.

9. The digital light processing 3D printing device based on nonlinear focusing multiple-partition exposure as claimed in claim 1, wherein the focusing aperture is connected with a synchronous wheel on a planetary reducer through a synchronous belt, the planetary reducer further subdivides the rotation of a focusing motor to drive the focusing aperture to rotate, and the movement of the focus of the curing light source is realized.