JPH08108481A - Photo-molding device - Google Patents

Abstract

PURPOSE: To provide a photo-molding device capable of improving curing efficiency which irradiates a photo-curable resin with light energy so as to form a three-dimensional molding, wherein optical outputs to be generated from a plurality of semiconductor laser units are focused on a position of beam focus light for irradiating the photo-curable resin with it so as to give an optical output having high energy density to the photo-curable resin. CONSTITUTION: A light irradiating device for irradiating a photo-curable resin 3 with light energy comprises a plurality of semiconductor laser units 12a, 12b, 12c... arranged adjacently. The laser beams to be generated from the semiconductor laser units are focused on a position of a beam focus light 13 at a point in a predetermined position so as to irradiate the photo-curable resin 3 with it.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical molding method for irradiating a photocurable resin with light energy in a desired arbitrary shape, laminating the obtained layered planar cured product, and forming a three-dimensional molded object. It relates to improvement of the device.

[0002]

2. Description of the Related Art Conventionally, various stereolithography methods have been known for irradiating a photocurable resin with light energy to form a three-dimensional molding, and recently, in particular, recently published by Nikkan Kogyo Shimbun. "Stereolithography" (published on October 30, 1990, author: Yoji Marutani, Kazuo Okawa, Seiji Hayano, Naoichiro Saito, Takashi Nakai).

As a conventional stereolithography method, a particularly common one is to provide a base plate as a modeling table near a resin liquid level in an open top type resin tank in which a photocurable resin is stored. By irradiating the free liquid surface with light from above, the first cured resin layer is formed on the plate, and then the plate is lowered to the inside of the tank by the thickness of the cured resin layer. Repeating the method of irradiating the resin on the first resin cured product layer with light to form the second resin cured product layer, and successively laminating sliced resin cured product layers. Is a method for forming a desired three-dimensional shape. This method is called the free liquid surface method because the table in the tank is sequentially submerged from the free liquid surface of the resin to form the molded article while laminating the cured product.

As another method, a base plate is provided near the bottom in a resin tank whose bottom is a light transmission window, and light is emitted from below the resin tank toward the plate through the bottom transmission window. The resin between the bottom surface and the bottom surface is cured as a resin cured material layer of the first layer, and then the plate is pulled up to peel off the resin cured material layer of the first layer from the bottom surface.
The method of forming the second resin cured material layer by light from below the resin tank between the first layer resin cured material layer and the bottom surface is repeated. Since the liquid level of the resin is regulated between the plate and the existing cured product layer, it is called the regulated liquid level method.

As a light source for irradiating the resin with light, a gas laser such as an Ar (argon) laser or a He-Cd (helium-cadmium) laser for irradiating light energy in the ultraviolet region is mainly used, or Semiconductor lasers that emit light energy in the visible light region are used.

[0006]

However, among the above-mentioned light sources, the gas laser which irradiates the light energy in the ultraviolet region has an influence on the human body, so that it is necessary to exercise caution when using it. A large power supply capacity is required as a means for obtaining the required laser emission end output, and further, a liquid cooling or air cooling cooling device or an ultraviolet protection device is required as a device attached to this light source device, which is inevitable. In addition, there is a problem that the entire device becomes large.

On the other hand, among the above-mentioned light sources, the semiconductor laser for irradiating light energy in the visible light region is very small and inexpensive, and can be provided to the market at a price lower than 10% of that of a gas laser. It has the advantage that it is a visible light laser and is excellent in handling, but on the other hand, it has an optical output of several mW to several tens of mW, which is extremely high compared to Ar (argon) lasers. It is weak and therefore has a problem that the time for forming a desired modeled object is longer than that of an optical modeling apparatus using an ultraviolet light source.

Further, when the semiconductor laser used as the light irradiating device is a single body, its light output has a wavelength longer than that of the ultraviolet light source, so that it is desired due to the mutual proximity effect of the light outputs or residual exposure. There is a problem that a shaped article different from the one described above is molded.

Under these circumstances, recently, in order to solve the problems of these gas lasers and semiconductor lasers, solid-state lasers are said to have the features of gas lasers and semiconductor lasers instead of these lasers. The light irradiation technology of utilizing the third harmonic of the Nd: YAG laser has been proposed.

However, this solid-state laser N
The d: YAG laser also has the advantages that the Nd: YAG rod has a long life and that the consumables such as the excitation lamp can be replaced at a lower cost than the replacement of the laser tube of the gas laser. There is no advantage in terms of maintainability and price, and even a laser device is composed of optical system parts for optical processing of a crystal element and laser light adjustment for producing a second harmonic and then a third harmonic from an excitation part. Therefore, there is a problem that the device capacity and the device price are the same as those of the conventional gas laser.

Further, this solid-state laser Nd: YA
The technique of utilizing the third harmonic of the G laser cannot reduce the size of the device for exciting the lamp, and further, in order to cure the ultraviolet curable resin,
Since it is necessary to irradiate light energy including ultraviolet rays or near-ultraviolet light having a wavelength of 0 nm or less, it is necessary to extract the third harmonic wave. Therefore, the light irradiation device is complicated,
High price, complicated maintenance, etc.
Overall, there is a problem that it has not reached the practical stage yet.

As described above, as a light irradiation technique in the stereolithography method, a technique using a gas laser, a semiconductor laser, or a solid-state laser has been disclosed, but these techniques at present are as described above. For some reason, as a practical matter, none of them is an effective means to reach the completion area of stereolithography.

[0013]

Claim 1 of the present invention was developed for the purpose of solving the problems of the conventional stereolithography method as described above, and a photocurable resin in a tank. Is irradiated with light energy to a desired arbitrary shape, the obtained layered planar cured product is laminated, and is a stereolithography device for molding a three-dimensional shape, as a light irradiation device for irradiating light energy, It is characterized by comprising a laser irradiation unit for converging the light output from a plurality of semiconductor lasers arranged adjacent to each other at the position of the beam converging light and irradiating the light curable resin.

According to a second aspect of the present invention, a light irradiating device for irradiating light energy focuses light output from a plurality of semiconductor lasers arranged adjacent to each other by continuous light at a position of beam focusing light to perform photo-curing. It is characterized in that the resin is irradiated onto the resin.

According to a third aspect of the present invention, a light irradiating device for irradiating light energy focuses the light output from a plurality of semiconductor lasers arranged adjacent to each other at the position of the beam focusing light by means of instantaneous pulsed light. Then, the photocurable resin is irradiated.

[0016]

According to the present invention, as a light irradiation device in a stereolithography apparatus, a plurality of light outputs oscillated from a plurality of semiconductor lasers arranged adjacent to each other are focused at the position of the beam focusing light to be photocurable. Since the resin is irradiated, it is possible to irradiate the photocurable resin with a light output having a high energy density that cannot be obtained by the light output from a single semiconductor laser, and the curing time of the resin in the irradiated portion by the light is significantly shortened. .

Further, since the light irradiating device is composed of a plurality of semiconductor lasers, the numerical aperture of the optical system in each laser unit, that is, the narrowing angle at which the light focuses is further increased, and further, between the laser units. By increasing the emission angle of the light output, it is possible to reduce the generation rate of an undesired shaped object due to the residual exposure that can be performed in the direction away from the light irradiation device rather than the desired solid object.

[0018]

EXAMPLES Next, the structure of the stereolithography apparatus according to the present invention will be described with reference to the stereolithography apparatus according to the regulated liquid level method shown in FIG. 1. Reference numeral 2 is a resin molding tank for storing the photocurable resin 3,
The resin molding tank 2 is formed in a groove shape around a transparent plate 4 having a raised central portion.

The photocurable resin 3 in the resin molding tank 2 is sucked by a pump 9 provided outside the tank and then supplied onto the transparent plate 4 from the pump 9 and provided on the resin molding tank 2. The schematizer 10 is horizontally moved to form a predetermined amount of the thin liquid layer 11 on the transparent plate 4 corresponding to the stacking slice pitch of the layered product, and the surplus resin is resin-molded by the schematizer 10. The circulation so as to be returned to the tank 2 is repeated.

Above the transparent plate 4, there is provided a molding base plate 1 which moves up and down by an elevator device (not shown), and below the transparent plate 4, an XY which freely moves in the vertical and horizontal directions. A computer unit 8 for focusing a plurality of laser beams from the light irradiation unit 6 to the position of the beam focusing light 13 by the plotter 5 and irradiating the photocurable resin 3 on the plate through the bottom surface of the transparent plate 4. A connected light irradiation device 7 is provided.

As shown in FIG. 3, the light irradiation device 7 provided below the transparent plate 4 has a plurality of semiconductor laser units 12a, 12b, 12c, ... By arranging them adjacent to the row and adjusting the arrangement angle of each unit, the laser light oscillated from each laser unit is focused at the position of the beam-focused light 13 at one point at a predetermined position, and the photocurable resin 3 It is attached so that it can be illuminated.

Further, each semiconductor laser unit 12a,
The adjustment of the array angles of 12b, 12c, ... Is performed by increasing the numerical aperture of the optical system in each laser unit, that is, by increasing the narrowing angle at which each laser beam is focused, or between the laser units. This is done by increasing the emission angle of the light output.

By appropriately adjusting the array angle between the laser units in this manner, it is possible to irradiate the beam-focused light 13 at one point where the laser beams are focused with a light output having an extremely high energy density. In addition, it is possible to reduce the generation rate of an undesired shaped object due to residual exposure that can be located at a position farther than the desired desired object position.

Incidentally, each of the semiconductor laser units 1 described above
As the laser light oscillated from 2a, 12b, 12c, ..., it is preferable that continuous irradiation light without any interruption is focused on the position of the beam focusing light 13 to irradiate the photocurable resin 3, but the beam focusing is preferable. The laser light focused on the position of the light 13 does not necessarily have to be continuous light, and may be instantaneous pulsed blinking light as long as it can obtain a light output with a high energy density as a whole. Good.

As means for irradiating the light output by the light irradiating device 7, as shown in FIG. 1, in addition to the method of directly loading the light irradiating device 7 incorporating the light irradiating section 6 on the XY plotter 5, X
-The Y plotter 5 is provided with the light irradiation unit 6 consisting of only the optical system, and the laser light focused at the position of the beam focusing light by the light irradiation device 7 arranged at the separated position is sent to the light irradiation unit 6 by the optical fiber. A method of irradiating the modeling portion can be selected.

The light irradiation device 7 and the XY plotter 5 are controlled by the computer unit 8. The computer unit 8 also controls the modeling base plate 1, the pump 9, the schema device 10, and the like. Calculating the planar shape of each layered slice for additive manufacturing of a three-dimensional shape, and calculating attribute data such as laser scanning speed and scanning pitch so that the planar shape desired by the light irradiation device 7 can be drawn on this. Do at the same time.

Further, the computer unit 8 has a built-in CAD and controls the additive manufacturing data from the CAD input of the three-dimensional model, or the three-dimensional model is designed by another computer, or the CT scanner, MRI. Various combinations are conceivable, such as one in which layered modeling control of the device is performed by exchanging data with the device that recognizes a three-dimensional solid shape by the three-dimensional shape measuring machine.

The resin to be cured by the stereolithography apparatus of the present invention is a resin known from Japanese Patent Laid-Open No. 6-15749 or a visible light curable photocurable resin such as KAYARAD-DF series resin manufactured by Nippon Kayaku Co., Ltd. Resins are mentioned.

The modeling process of the optical modeling apparatus by the regulated liquid level method shown in FIG. 1 will be described. First, the pump 9 supplies the photocurable resin 3 onto the transparent plate 4, and then the schema apparatus 10 is operated. By moving and scanning, a thin liquid corresponding to the thickness corresponding to the slice data of the modeled object on the transparent plate 4, that is, the thickness of the modeled object layer 15 in the three-dimensional laminated object 12 shown in FIG. 2A. Layer 1
1 is formed.

Next, the modeling base plate 1 is lowered onto the thin liquid layer 11, and the thin liquid layer 11 is set so as to be sandwiched between the transparent plate 4 and the modeling base plate 1, and is desired by the computer unit 8. By controlling the planar shape of the three-dimensional layered product and scanning the light irradiation device 7 based on the obtained data, the laser beams oscillated from the laser units 12a, 12b, 12c, Focused beam 13 at one point at a predetermined position
At the position of, the photo-curable resin 3 on the transparent plate 4 is focused.
The first shaped object layer 15 as shown in FIG.
Is molded.

After the first shaped article layer 15 is formed, the shaped base plate 1 is moved up to the transparent plate 4.
The first modeling layer 15 is peeled off from the top, and in the next step, the thin liquid layer 11 is provided on the transparent plate 4 by the same procedure as described above, and then the modeling base plate 1 is lowered to remove the thin layer. The liquid layer 11 is sandwiched between the first modeling layer 15 and the transparent plate 4, and the similar operations are repeated to sequentially laminate the modeling layers 15 to obtain a desired predetermined three-dimensional lamination. The molded article 14 is molded.

As the stereolithography apparatus, as in the regulated liquid level method described in this embodiment, light irradiation is performed from below the thin liquid layer 11 of the photocurable resin on the transparent plate 4, and the transparent plate 4 is irradiated. A thin liquid layer in which the molded article layer 15 to be molded above is peeled off from the transparent plate 4 and the existing laminated molded article layer 15 and a new molded article layer 15 to be molded next on the transparent plate 4 are sequentially laminated. In addition to the above method, even with the same regulated liquid level method, there is a downward exposure method in which molding is performed in a tank in which the resin liquid is stored without forming a thin liquid layer on the transparent plate, or the bottom surface of the resin tank and above it. After molding the first layer of the molded article by irradiating light from above between the transparent plates arranged in, the transparent plate is pulled upward and the new molded article is sequentially laminated on the molded article. The upper exposure method, or the above-mentioned freedom There are known optical stereolithography means surface method, etc., but it is sufficient possible to apply the improvements described in the present invention to these various stereolithography.

[0031]

As described above, according to the present invention, as the light irradiation device, the light output from a plurality of semiconductor laser units arranged adjacent to each other is focused on the position of the beam focusing light so that the photo-curable resin. As compared to the light output when the semiconductor laser is a single unit, it is possible to irradiate the photocurable resin with a higher density of concentrated light energy, so that the photocurable resin can be irradiated with light at a predetermined position. It is possible to significantly reduce the unit curing processing speed required for curing the resin. As a result, the X required for molding the desired shaped object
-The movement operation time of the light irradiation device by the Y plotter is short, and the work efficiency as a whole can be significantly improved.

Further, since the light irradiation device is composed of a plurality of semiconductor laser units, the numerical aperture of the optical system in each laser unit is increased, and the emission angle of the light output between the laser units is increased. Due to the residual exposure that can be performed in the direction away from the light irradiation device rather than the desired solid matter, it is possible to reduce the occurrence rate of undesired shaped objects, so that it is possible to efficiently form highly accurate modeling without loss. it can.

Further, in the stereolithography apparatus of the present invention, it is possible to provide an inexpensive light irradiation apparatus as compared with the gas laser, which can greatly reduce the maintenance and inspection cost of the light irradiation apparatus, and Since miniaturization is possible, there is an effect that the degree of freedom in designing the device design can be dramatically improved and an inexpensive stereolithography device can be provided as a whole.

[Brief description of drawings]

FIG. 1 is a front perspective view showing a configuration of an optical shaping apparatus according to the present invention.

FIG. 2 is a conceptual diagram of a layered three-dimensional model according to the stereolithography method of the present invention, where (a) is the shape of a three-dimensional layered model, and (b) is slice data for layered modeling that forms each layer of the modeled object. Show.

FIG. 3 is a perspective view showing a configuration of a light irradiation device used in the stereolithography apparatus of the present invention.

[Explanation of symbols]

 1: Modeling base plate 2: Resin modeling tank 3: Photocurable resin 4: Transparent plate 5: XY plotter 6: Light irradiation unit 7: Light irradiation device 8: Computer unit 9: Pump 10: Schematic device 11: Thin liquid Layers 12a, 12b, 12c: Semiconductor laser unit 13: Beam focusing light 14: Three-dimensional layered object 15: Object layer

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical display location H01S 3/10 Z // B23K 26/06 A B29K 105: 24 (72) Inventor Shizuo Shimizu Tokyo 2206 Naruse, Machida-shi

Claims (3)

[Claims] 1. A stereolithography apparatus for irradiating a photocurable resin in a tank with light energy in a desired arbitrary shape, laminating the obtained layered flat cured product, and molding a three-dimensional shaped product. As a light irradiating device for irradiating light energy, a laser irradiating unit for converging the light output from a plurality of semiconductor lasers arranged adjacently to the position of the beam converging light and irradiating the photocurable resin is provided. A stereolithography apparatus characterized by the above. 2. The stereolithography apparatus according to claim 1, wherein light output from a plurality of semiconductor lasers arranged adjacent to each other is focused on a position of beam focusing light by continuous light to irradiate the photocurable resin. 3. The stereolithography apparatus according to claim 1, wherein the light output from a plurality of semiconductor lasers arranged adjacent to each other is focused on the position of the beam focusing light by an instantaneous pulsed light, and the photocurable resin is irradiated with the focused light. .