JPH0752262A - Liquid level-smooting tool in optical shaping device - Google Patents

Abstract

PURPOSE:To easily adjust a vertical position of a liquid level-smoothing tool from a liquid level, prevent an adhesion of a photosetting resin, and rapidly and surely smooth a liquid level without damaging a work by a method wherein in smoothing a liquid level of a photosetting resin using a liquid level smoothing tool, the contact area of the tool with the resin is reduced for the reduction of a resistance between the both. CONSTITUTION:In an optical shaping device provided with a liquid photosetting resin contained in a container 2, a light emitting means for forming a work by emitting a laser light to a liquid level 5 of the photosetting resin, and a work lifting/lowering means for settling the work in the photosetting resin, a metal wire 32 stretched between the both sides of the container 2 is so provided as to move along the liquid level 5 when the work is settled into the photosetting resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid leveling tool in a stereolithography apparatus for accurately producing a three-dimensional object by a photochemical curing reaction when a liquid photocurable resin is irradiated with laser light.

[0002]

2. Description of the Related Art Conventionally, there has been known a technique of irradiating a liquid photocurable resin with a laser beam and successively curing the resin in the irradiated portion to produce a three-dimensional object having a desired shape. This technique is as shown in FIGS. 7 to 10, for example. First, the table 3 is set to a depth d below the liquid surface of the container 2 filled with the liquid photocurable resin 1, and the resin liquid is allowed to exist on the table 3. The depth d of this resin liquid is the same value as the slice interval of the cross-sectional figure obtained by cutting the three-dimensional shape designed on the CAD system at equal intervals in the horizontal direction.

Next, in this state, the lowermost layer of the data of the cross-sectional figure is taken out, and the laser beam 4 is irradiated onto the liquid surface 5 along the shape as shown in FIG. Then, the liquid layer having the depth d is solidified to form the work W1. Next, as shown in FIG. 9, the table 3 is lowered by the depth d, and the work W1 is allowed to settle in the liquid, and the uncured resin liquid is formed thereon by the depth d. So again C
The layer next to the lowermost layer is extracted from the data of the cross-sectional figure of the AD system, and irradiation with the laser beam 4 is performed as shown in FIG. The second layer work W2 is laminated and joined on the first layer work W1. In this way, the above operation is repeated for the data of the third layer, the fourth layer and all the cross-section figures, and after the solidification of the layer is completed for all the data, the table 3 is raised above the liquid level 5 You can take things out.

By the way, the depth of the liquid layer d which is solidified by one irradiation of the laser beam 4 is extremely small, about 0.1 to 0.5 mm. Therefore, the depth d of the uncured resin liquid formed on the work when the table 3 is lowered is also 0.1.
It is extremely small, about 0.5 mm, and the photocurable resin liquid 1 used for it has an appropriate viscosity. Therefore, as shown in FIG. 11, when the table is lowered by one layer to form the uncured resin liquid on the work W, the surface between the end of the work W and the liquid surface 5 is There is a problem that tension is likely to be generated and the uneven portion 8 is easily generated, and the uncured resin liquid does not flow into the work W only in that portion, and the smoothness of the liquid surface 5 is impaired.

In order to solve such a problem in the prior art, a spatula 9 is provided on the liquid surface 5 as shown in FIG. 11, for example, and when the table is lowered, the liquid is removed. There has been a method in which the spatula 9 is moved along the surface 5 and the tip of the spatula 9 is disturbed to weaken the surface tension to obtain the smoothness of the liquid surface 5 (JP-A-1- 115
620).

[0006]

However, in the method of leveling the liquid surface 5 at the tip of the spatula 9 as described above, the spatula 9 is used.
The contact area between the tip of the and the photo-curable resin 1 increases,
To that extent, the resistance at the tip when the spatula 9 is moved also increases. Therefore, if the height position of the spatula 9 with respect to the liquid surface is not strictly adjusted, the upper surface of the work W may be damaged by the tip of the spatula 9, and the tip of the spatula 9 may be covered with a photocurable resin. There was a problem of easy adhesion.

Therefore, according to the present invention, the contact area with the photocurable resin when leveling the liquid surface is reduced and the resistance between the two is reduced, so that the height position adjustment with respect to the liquid surface can be easily performed. At the same time, it is an object of the present invention to provide a liquid leveling tool which prevents the photo-curable resin from adhering to the surface and can level the liquid level quickly and surely without damaging the work.

[0008]

[Means for Solving the Problems] That is, in order to solve the above technical problems, the present invention provides a photocurable resin solution housed in a container and a photocurable resin solution. In a stereolithography apparatus including a light irradiation means for irradiating a laser beam on the liquid surface of a resinous resin solution to form a work, and a work elevating means for causing the work to settle in the photocurable resin solution,
It is characterized in that it is provided with tension lines extending between both sides of the container and moving along the liquid surface when the work is settled in the photocurable resin solution.

[0009]

According to the above-mentioned means, when the uncured resin liquid is formed on the work by slightly lowering the table, the tension line is moved in parallel along the liquid surface. Then, the tension line advances so as to cut the resin liquid, and breaks down the surface tension portion generated at the end portion of the work. As a result, the surface tension of the liquid surface is lowered, the fluidity of the resin liquid is improved, and the uncured resin liquid is quickly formed on the work, and the smoothness of the liquid surface is maintained.

[0010]

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a schematic diagram of a stereolithography apparatus. In this figure, reference numeral 2 is a container for containing the liquid photocurable resin 1, 3 is a table for moving up and down in the container 2, and W is a work made on the table 3. The up-and-down movement of the table 3 is controlled by the Z-axis moving table 10, and the left-right and forward-backward movements of the container 2 are controlled by the X-axis moving table 11 and the Y-axis moving table 12, respectively. The CAD data 13 designed on the CAD system are taken out one after another via the personal computer 14, and the light irradiation means 1 is based on the data.
The liquid surface 5 of the photocurable resin 1 is irradiated with the laser light 4 from the laser light 5.

2 and 3 concretely show the liquid leveling tool 20 arranged on the above-mentioned container 2. In this embodiment, the container 2 is a box-shaped container made of stainless steel and has a rectangular planar shape. The upper part of the peripheral edge of the container 2 has a double wall structure, and a drip groove 23 for accumulating the photocurable resin 1 overflowing from the container 2 is formed between the inner peripheral wall 21 and the outer peripheral wall 22 around the entire circumference. It is provided over. The upper surface 24 of the inner peripheral wall 21 is slightly higher than the upper surface 25 of the outer peripheral wall 22. Further, the bottom surface of the drip groove 23 is provided with a drain hole 27 communicating with the outside,
The photocurable resin 1 overflowing to the outside is returned to the injection pipe 28,
The container 2 is replenished again from its tip.

On the other hand, the liquid leveling tool 2 placed on the container 2
Reference numeral 0 denotes a bar member 30 spanned between the left and right outer peripheral walls 22a and 22b on the long side of the container 2 having a rectangular planar shape, and the outer peripheral walls 22a and 22b from both ends of the bar member 30.
Pair of slide arms 31a, 31 that wrap around the lower side of the
b, and a metal wire 32 stretched along the longitudinal direction on the lower surface side of the bar member 30. A slide rail 33 for guiding the slide arms 31a and 31b is provided under the left and right outer peripheral walls 22a and 22b of the container 2.
a and 33b are provided.

Further, the lower surface of the bar member 30 is provided with steps 34a and 34b near both ends, in particular, at positions on the drip groove 23, and the inner peripheral wall 21 of the container 2 is provided.
The upper surface 24 of the bar member 30 and the lower surface 35 on the end side of the bar member 30 are flush with each other, and the lower surface 36 on the center side and the upper surface 2 of the inner peripheral wall 21.
A gap is formed between the No. 4 and. Therefore, the bar material 3
The lower surfaces 35 and 36 of 0 do not contact the upper surfaces 24 and 25 of the inner peripheral wall 21 and the outer peripheral wall 22 of the container 2. In addition, in the central portion of the bar member 30, a long hole 3 penetrating in the vertical direction is formed.
7 is opened, and the metal wire 32 stretched over the lower surface side of the bar member 30 can be confirmed from above the bar member 30.

The metal wire 32 is the bar material 30 as described above.
Of the bar material 30, the ends of the bar material 30 are in contact with the bottom surface 35 of the bar material 30 on the side of the bar material 30, and are wrapped around the top surface of the bar material 30 and then fixed by screws 38a and 38b. The one end of the metal wire 32 is fixed to the screw 38a via the spring 39, so that the metal wire 32 can be held in an appropriate tension state. By doing so,
The metal wire 32 moves in the longitudinal direction of the container 2 as the bar member 30 slides on the container 2.
Both ends of 2 move while sliding on the upper surface 24 of the inner peripheral wall 21 of the container 2. That is, the metal wire 32 moves so as to cut off the liquid surface 5 of the photocurable resin 1 when the container 2 is filled with the photocurable resin 1. The position of the metal wire 32 with respect to the liquid surface 5 is not limited to the above-mentioned one, and for example, as shown in FIG. 4, the pair of pins 40a, 40b may be downward from the lower surface 36 on the center side of the bar member 30. May be projected into the liquid, and the metal wire 32 may be stretched over the tips of the pins 40a and 40b to move the photocurable resin 1 in the liquid.

Types of metal wire 32 used in the present invention include piano wire, stainless wire, and tungsten wire. Further, the diameter of the metal wire 32, the number of wires arranged on the lower surface of the bar member 30, and the vertical / horizontal directionality when arranging a plurality of metal wires 32 and the gap between the metal wires 32 are particularly It is not limited, and it is necessary to select the most suitable one depending on the viscosity of the photocurable resin 1.

Further, in the present invention, when the liquid leveling tool 20 is operated, the metal wire 32 is instantly heated, and in that state, the liquid level 5
May be leveled. This is because the photocurable resin 1 that has touched the metal wire 32 can be locally and temporarily heated by heating the metal wire 32, so that deterioration of the photocurable resin 1 caused by heating can be prevented. While this can be prevented as much as possible, it is possible to expect a decrease in the liquid viscosity of the photocurable resin 1 due to heating. As a result, the liquid level 5 of the photocurable resin 1
The surface tension is reduced, and the liquid surface 5 is more easily leveled when the metal wire 32 is moved.

The photo-curable resin 1 used in this embodiment includes, for example, modified polyurethane, methacrylate, urethane acrylate, epoxy acrylate, photosensitive polyimide, amino alkyd and the like. When used, these resins are used alone or in combination of two or more. Further, not only the photo-curable resin 1, but also a powdered material such as ceramics or titanium, carbon fiber or the like may be mixed therein, in which case it is possible to form a composite material.

Next, the operation of the liquid leveling tool 20 having the above structure will be described with reference to FIGS. 5 and 6. First, CAD
The liquid level 5 of the photocurable resin 1 is irradiated with the laser light 4 based on the three-dimensional sectional figure data designed on the system, while the liquid leveling tool 20 is on standby at one side of the container 2. deep. Then, after the work W is formed on the table 3 by the irradiation of the laser beam 4, the table 3 is moved to the depth d.
Then, the work W is allowed to settle in the liquid. At this time,
As shown in FIG. 6, there is a height difference d between the upper surface of the work W and the liquid surface 5, but as described above,
The unevenness 8 is formed on the upper surface of the workpiece W by the surface tension generated between the end of the unevenness and the liquid surface 5, and the resin is prevented from flowing into the unevenness 8.

The operation of the liquid leveling tool 20 is performed together with the replenishment of the photocurable resin 1 dropped from the injection pipe 28 onto the liquid level 5. As shown in FIG. 6, the replenishment liquid 1a is filled on the work W by the replenishment of the photocurable resin 1, but the smooth liquid surface 5 is not formed due to the influence of the surface tension described above. With respect to such a liquid level 5, the liquid leveling tool 20 guides the slide arms 31a and 31b to the slide rails 33a and 33b of the container 2 so that the bar member 30 moves on the liquid level 5 of the container 2. It slides in the horizontal direction, and along with this, the metal wire 32 moves so as to cut the liquid surface 5. That is, the photocurable resin 1 in the container 2 is filled to the full extent by being replenished on the liquid surface 5 as described above, and is slightly raised from the upper surface 24 of the inner peripheral wall 21 of the container 2 due to surface tension. However, since the metal wire 32 slides on the upper surface 24 of the inner peripheral wall 21 in a sliding manner, the metal wire 32 advances while cutting a portion which is higher than the upper surface 24 of the inner peripheral wall 21. As a result, the surface tension formed at the end of the work W and the surface tension formed between the surface of the work W and the newly replenished liquid are reduced, the liquid flows into the uneven portion 8, and the excess liquid is drip groove 23. As a result, the smooth liquid surface 5 is formed.

As shown in FIG. 4, even when the metal wire 32 is set below the liquid surface of the photocurable resin 1, the surface tension is the same as that described above at a position shallow from the liquid surface 5. There is an effect of reducing. Thus, by breaking the surface tension of the photocurable resin 1, the surface activity of the resin liquid is promoted to improve the fluidity, and the photocurable resin 1 quickly flows into the upper surface of the work W and is formed on the work W. The convex and concave portions 8 thus formed are completely covered to form a smooth liquid surface 5. Further, since the metal wire 32 is thin, the resistance between the metal wire 32 and the photocurable resin 1 is small, and the liquid surface 5 is hardly disturbed when the metal wire 32 moves. Furthermore, since the contact area between the metal wire 32 and the photocurable resin 1 is small, the photocurable resin 1 is less likely to adhere to the periphery of the metal wire 32.

[0021]

As described above, according to the liquid leveling tool in the stereolithography apparatus of the present invention, the liquid level is leveled by the tension lines stretched on both sides of the container. Since the resistance between the resin and the resin is small and the liquid surface is not disturbed during leveling, the height position of the tension line with respect to the liquid surface can be easily adjusted. Also, the tension line has a small contact area with the photocurable resin when leveling the liquid surface, and the photocurable resin does not easily adhere to the tension line. It is possible to secure a stable value.

[Brief description of drawings]

FIG. 1 is a schematic diagram illustrating an example of a stereolithography apparatus.

FIG. 2 is a perspective view showing an embodiment of the liquid leveling tool according to the present invention.

3 is a sectional view taken along the line AA in FIG.

FIG. 4 is a sectional view similar to FIG. 3, showing another embodiment of the liquid leveling tool.

FIG. 5 is a cross-sectional view showing a state in which the liquid leveling tool is on standby.

FIG. 6 is a cross-sectional view showing a state in which a liquid leveling tool is being operated.

FIG. 7 is a cross-sectional view when a table showing the first procedure of stereolithography is set.

FIG. 8 is a cross-sectional view of laser irradiation of the first layer showing a second procedure of stereolithography.

FIG. 9 is a cross-sectional view showing the third procedure of stereolithography when the table is lowered into the resin liquid.

FIG. 10 is a cross-sectional view of laser irradiation of a second layer showing a fourth procedure of stereolithography.

FIG. 11 is a cross-sectional view showing an example of a conventional liquid leveling tool.

[Explanation of symbols]

 W Work 1 Photocurable resin 2 Container 3 Table 4 Laser light 5 Liquid level 10 Z-axis moving table (work lifting means) 20 Liquid leveling tool 32 Metal wire (tension line)

Claims (1)

[Claims] 1. A photocurable resin solution housed in a container, a light irradiation means for irradiating a laser beam on the surface of the photocurable resin solution to form a work, and a photocurable resin solution. In a stereolithography apparatus equipped with work elevating means for causing a work to settle, a tension line that is stretched between both sides of the container and that moves along the liquid surface when the work is settled in the photocurable resin solution. A liquid leveling tool for a stereolithography apparatus, which is characterized by being provided.