JP2001062928A - Three-dimensional fabrication device, method and material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a three-dimensional body fabrication device, higher in speed, lower in cost, lower in power consumption and more silent than a conventional three-dimensional fabrication device, not requiring an additional support to a three-dimensional matter, capable of burying an already prepared member in the three-dimensional matter and not providing the surface of the three- dimensional matter with a step due to lamination. SOLUTION: A three-dimensional fabrication device is constituted of a vessel for receiving a liquid resin, in which micro-capsules M for releasing a curing agent are dispersed while being collapsed by ultrasonic waves concentrated in a focus, a plurality of oscillators T1-Tn for generating the ultrasonic waves and focussing in the resin, a route planning software C1 for obtaining the route of focuses of curing the resin R based on the configuration of the three- dimensional matter, and an ultrasonic wave oscillating circuit C2 for controlling the phases of ultrasonic waves, generated by the plurality of oscillators T1-Tn, to move the focus along the route of the focuses.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional molding apparatus for producing a three-dimensional object based on three-dimensional shape data.
The present invention relates to a three-dimensional molding apparatus which is low-cost, low-power consumption, quiet, does not need to add a support to a three-dimensional object, and can embed an existing member inside the three-dimensional object.

[0002]

2. Description of the Related Art A technique for rapidly and easily realizing three-dimensional data of a computer is generally called rapid prototyping (RP). An optical molding method in which a liquid synthetic resin is exposed to light to cause a photochemical reaction to partially solidify,
A selective laser sintering method (SLS method) in which powder is irradiated with a laser beam to partially sinter the powder is well known. Details of the RP are described in, for example, "Laid Manufacturing System" (Takeo Nakagawa / Yoji Marutani / Industry Research Committee).

However, since the conventional RP device has many movable parts, the operation speed is not so high. In addition, since a laser is used, both the purchase price and the running cost are high. The power consumption was large, and the sound of the fan to cool the laser was disturbing.

Further, in the conventional RP apparatus, since a three-dimensional shape is created by lamination, depending on the shape of the three-dimensional object, it is necessary to add a support (supporting member) for shaping and remove it later. It has also been impossible to deposit a material around a reinforcing member made by another method and to perform modeling such that the reinforcing member is embedded in a three-dimensional object. In addition, since a step due to the lamination appeared on the surface of the three-dimensional object, it was necessary to perform polishing or the like after modeling in order to smooth the surface of the three-dimensional object.

[0005]

SUMMARY OF THE INVENTION The present invention is faster, lower cost, lower power consumption and quieter than the conventional three-dimensional molding apparatus.
It is an object of the present invention to provide a three-dimensional object forming apparatus which does not need to add a support to a three-dimensional object, can embed an existing member inside the three-dimensional object, and does not have a step due to lamination on the surface of the three-dimensional object.

[0006]

SUMMARY OF THE INVENTION The object of the present invention is to provide a three-dimensional molding apparatus comprising: a container for containing a liquid resin in which microcapsules, which are broken by ultrasonic waves focused on a focal point and release a hardener, are dispersed; A plurality of vibrators that generate and focus the inside of the resin, path planning software for finding a path of the focal point for curing the resin based on the shape of the three-dimensional object,
This problem can be solved by using an ultrasonic oscillation circuit that adjusts the phase of ultrasonic waves generated by a plurality of vibrators and moves the focal point along a path.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIG. 1 shows the overall configuration of a three-dimensional printing apparatus A according to the present invention. The three-dimensional modeling device A is for modeling a three-dimensional object S having a three-dimensional shape described by the three-dimensional shape data D, and includes a water tank VW, a resin tank VR, a plurality of vibrators T1 to Tn, a path plan. It includes software C1 and an ultrasonic oscillation circuit C2.

[0008] The three-dimensional printing apparatus A uses a liquid resin R as a material of the three-dimensional object S. Many microcapsules M are dispersed in the resin R. Emulsions are made by mixing two liquids that do not dissolve each other, such as water and oil, and making the droplets very fine so that they do not separate.
Call. Microcapsules are small capsules obtained by emulsifying two types of liquids, which generate a solid by causing a chemical reaction (interfacial polymerization reaction) at the interface. Many of the microcapsules contain 0.
It has a diameter of 1 mm or less and a spherical shape.

When two types of liquids that do not dissolve in each other are emulsified, one of the liquids becomes fine droplets and is dispersed in the other liquid. The liquid in the form of droplets is referred to as a dispersoid, and the liquid in the form of no droplets is referred to as a dispersion medium. When microcapsules are formed, a dispersoid will be encapsulated inside. The dispersoid and the dispersing medium do not dissolve each other as they are, but the resulting microcapsules are filtered out of the dispersing medium, and mixed with another dispersing medium, so that the dispersoid and the dispersing medium that dissolve in each other are formed into a shell ( Outer shell).

When a volatile substance is included in the dispersoid and the pressure of the microcapsules generated under high pressure is reduced, the encapsulated volatile components evaporate. Is obtained. The air-containing microcapsules change in diameter in response to a slight change in pressure, and resonate when given a specific frequency of vibration. In particular, when resonance is remarkable, the aerated microcapsules are broken. Such a phenomenon is described as “Aerated microcapsules DD using resonant ultrasonic waves.
Measurement and control of S "(Ken Ishihara / BME Vol. 6 No. 1 / MME Society of Japan) and the like.

The three-dimensional molding apparatus A forms a three-dimensional object S by applying a strong vibration to the microcapsule M to break the microcapsule M, to release the enclosed curing agent M2, and to cure the liquid resin R. .

The resin tank VR of the three-dimensional molding apparatus A contains a liquid resin R containing microcapsules M. The hardening agent M2 is sealed in the microcapsule M in advance. The ultrasonic waves generated from the plurality of vibrators T1 to Tn are:
A focal point F is formed inside the resin R. If the intensity of the ultrasonic wave is adjusted, the microcapsule M can be broken only at the focal point F without breaking the microcapsule M except at the focal point F where the ultrasonic wave is concentrated. This makes it possible to cure only one point inside the resin R.

A water tank VW is placed outside the resin tank VR. The water W filled therein contains the vibrators T1 to Tn.
Is transmitted to the resin R in the resin tank VR. The resin tank VR is made of a material that does not reflect, scatter, or refract ultrasonic waves, and can be easily removed from the three-dimensional printing apparatus A. With such a configuration, the amount of the resin R used can be reduced, and the vibrators T1 to T
n is easier to clean. Of course, when the amount of the resin R to be used and the trouble of cleaning the resin tank VR do not matter, the water tank VW does not always have to be placed outside the resin tank VR.

When the three-dimensional shape data D is given to the three-dimensional modeling apparatus A, the path planning software C1 operates to generate the scanning path data D1. The scanning path data D1 is data describing the path of the focal point F for curing the resin R.
As in the case of the conventional RP apparatus, the scanning path data D1 can be generated from the three-dimensional shape data D by using an algorithm in which the three-dimensional shape is divided into a number of cross sections and stacked.

The ultrasonic oscillation circuit C2 sends signals to a plurality of vibrators T1 to Tn via a signal line X to generate ultrasonic waves. Further, based on the scanning path data D1, the generation and opening of the ultrasonic wave are opened and closed. Further, the phases of the ultrasonic waves generated by the respective vibrators T1 to Tn are individually adjusted, and the scanning path data D
The focal point F is moved along the path described by 1.

The principle of moving the focal point F by adjusting the phase of the ultrasonic waves generated by the vibrators T1 to Tn will be described with reference to FIGS. Here, a virtual vibrator is placed at the focal point F, and the vibrators T1 to Tn are pickups (sound receivers).
It is assumed that it functions as. Under such an assumption, the pressure wave transmitted from the focal point F is generated by a plurality of vibrators T1.
2 to Tn are shown in FIG.

FIG. 2A shows the geometric arrangement of the vibrators T1 to Tn and the focal point F. FIG. 2B shows the waveform of the pressure wave transmitted from the focal point F and the waveform of the pressure wave reaching the vibrators T1 to Tn. The pressure wave transmitted from the focal point F at time 0 reaches the exciter Ti at time ti due to a time delay caused by the finite propagation velocity.

Next, a method of transmitting a pressure wave that concentrates on the focal point F from the vibrators T1 to Tn will be considered. FIG. 3 shows how the pressure waves transmitted from the plurality of vibrators T1 to Tn reach the focal point F.

FIG. 3A shows the geometric arrangement of the vibrators T1 to Tn and the focal point F. It has been already known that it takes time ti for the pressure wave transmitted from the exciter Ti to reach the focal point F. Therefore, if the pressure wave is transmitted from the exciter Ti at time -ti, the pressure waves transmitted from the individual exciters T1 to Tn at time 0 reach the focal point F at the same time. FIG. 3B shows a waveform of the pressure wave transmitted from the vibrators T1 to Tn under such a condition, and a waveform of the pressure wave reaching the focal point F.

Since the actual ultrasonic wave is not a single pressure wave but a continuous wave, the phase is controlled instead of the time at which the pressure wave is transmitted. In a continuous wave, the pressure wave is not always concentrated at one point. However, if the number of the vibrators T1 to Tn is increased, the pressure wave is finally concentrated to only one point. Can be. This is known as the basic principle of holography, and is described, for example, in "Three-dimensional image engineering" (Takataka Ohkoshi / Asakura Shoten).

If the speed at which the ultrasonic wave propagates through the resin R is known, it is possible to collect the ultrasonic wave at an arbitrary point inside the resin R and selectively break the microcapsules M there. is there.

FIG. 4 shows the structure of the microcapsule M.
The microcapsule M is made of a shell M1 of a polymer material, and has a structure in which a curing agent M2 and bubbles M3 are sealed inside. According to the prior art, a diameter of 10 μm or less can be easily obtained. The curing agent M2 is a kind of a polymerization initiator, and the oligomer contained in the liquid resin R
It has the property of initiating and curing the polymerization reaction of monomers.
As the bubbles M3, those in which a vapor of a hydrocarbon such as isopentane / hexane is sealed are obtained by a conventional technique.

FIG. 5 shows a procedure in which the three-dimensional modeling apparatus A performs modeling. The three-dimensional modeling device A performs the modeling of the three-dimensional object S in two steps of a latent image generation step P1 and a curing reaction step P2.

In the latent image generation step P1, ultrasonic waves are transmitted to the resin R including the microcapsules M, and the individual vibrators T1 to T1 are transmitted.
The focal point F is created inside the resin R by adjusting the phase of the ultrasonic wave generated from Tn. Then, the focus F is moved along the shape of the three-dimensional object S to perform three-dimensional drawing. As a result, the microcapsules M are broken at the portion corresponding to the inside of the three-dimensional object S, and the enclosed hardener M2 is released and diffuses into the resin R. However, since the rate of the polymerization reaction of the oligomer / monomer contained in the resin R is reduced, the curing of the resin R does not yet occur at this point.

In the curing reaction step P2, the transmission of the ultrasonic waves is stopped and the resin R is allowed to stand for a certain period of time to advance the curing of the resin R.
At this point, the three-dimensional object S appears in the resin R. Take it out and wash it. The procedure is divided into the latent image generation step P1 and the curing reaction step P2 in order to avoid the influence of the change in the propagation speed of the ultrasonic wave accompanying the curing of the resin R. This allows the resin R to be treated as homogeneous while scanning is being performed, so that the ultrasonic oscillation circuit C2 having a simple configuration can be used.
Even when using, modeling can be performed with high accuracy.

When a flow occurs in the resin R while scanning the focal point F in the latent image generation step P1 or while the resin R is being cured in the curing reaction step P2, the three-dimensional object S is formed. It causes deformation. Generally, the viscosity of resin R is high,
The deformation is not so great. However, when it is desired to produce the three-dimensional object S with a particularly high precision, it is also effective to use a fluid such as a gel or a paste that does not flow until a certain stress is applied, that is, a resin R having a property of a Bingham fluid. It is.

As described above, in the three-dimensional modeling apparatus A, there is no movable part for performing scanning, and there is no need to wait for the liquid surface to settle, so that modeling can be performed at high speed and quietly. In addition, since a laser that is expensive, consumes a large amount of power, and does not require regular maintenance is used, modeling can be performed at low cost. In addition, there is almost no flow of the resin R,
Power is not applied. Therefore, it is not necessary to add a support to the three-dimensional object S, and the three-dimensional object S having a particularly complicated shape can be formed. Also, a soft and easily deformable material such as rubber can be used as the molding material.

(Second Embodiment) The resonance frequency of the air-containing microcapsule changes depending on the diameter and the thickness of the shell M1. Therefore, two types of microcapsules having different resonance frequencies, that is, a microcapsule M and a colored microcapsule MA are prepared, and one coloring microcapsule MA is filled with a coloring agent M4 instead of the curing agent M2 sealed in the microcapsule M. Keep it. If the resin R containing these microcapsules is used as a modeling material, modeling can be performed while coloring an arbitrary portion of the three-dimensional object S by selectively using ultrasonic waves of a plurality of frequencies.

(Third Embodiment) In the three-dimensional printing apparatus A, unlike the conventional RP apparatus, it is not always necessary to perform the printing by lamination. Therefore, the path of the focal point F for curing the resin R can be extremely freely planned.

For example, if the inside of the three-dimensional object S is formed first and the surface is formed later, the time required for forming the surface of the three-dimensional object S is reduced, and the flow of the resin R during the period is reduced. Since deformation of the three-dimensional object S is suppressed, high-precision modeling is enabled. FIG. 6 shows an example of a scanning path of the focal point F in which the inside of the three-dimensional object S is formed first and the surface is formed later.

It is also possible to embed a member, such as a reinforcing material, made in advance by another method inside the three-dimensional object S. In this case, a means for holding the embedding member I is provided in the resin tank VR, and scanning is performed so as to cure the resin R around the embedding member I, and modeling is performed.

(Fourth Embodiment) Even microcapsules M that do not contain bubbles M3 can be broken by applying strong vibration, and can be used in the same manner as air-containing microcapsules. The microcapsules M that do not include the bubbles M3 can be obtained at a lower cost than the air-containing microcapsules, whereby the price of the resin R can be reduced. However, since there is no sharp resonance frequency as in the case of the air-containing microcapsules, it is more difficult to apply the method to selectively use ultrasonic waves of many frequencies than to use the air-containing microcapsules.

(Fifth Embodiment) In order to move the focal point F, instead of changing the phase of the ultrasonic waves generated by the plurality of vibrators T1 to Tn, a pump placed in the water tank VW is used. A method of moving the shakers T1 to Tn by a mechanism such as a feed screw can also be used. FIG. 7 shows a configuration of a three-dimensional printing apparatus Aa based on a method of moving the vibrators T1 to Tn themselves.

The three-dimensional printing apparatus Aa is different from the three-dimensional printing apparatus A in which the vibrators T1 to Tn are fixed to the water tank VW, and includes a scanning mechanism driving circuit C3, an X-direction moving device B1, and a Y-direction moving device B2. , Z-direction moving device B3. These move the focal point F along the path of the point where the resin R is cured, which is described by the scanning path data D1.
The exciters T1 to Tn are driven. Further, since the ultrasonic oscillation circuit C2a of the three-dimensional printing apparatus Aa does not have a function of adjusting the phase of the ultrasonic waves generated by the vibrators T1 to Tn, ultrasonic waves having the same phase are output from all the vibrators T1 to Tn. appear.

In this method, since the positional relationship between the individual exciters T1 to Tn and the focal point F is fixed, the exciters T1 to Tn are fixed.
Can be optimized. Therefore, even if the number of the vibrators T <b> 1 to Tn is reduced, the ultrasonic waves can be focused on the focal point F, and modeling with high resolution can be performed.

[0036]

According to the first aspect, a three-dimensional object can be produced at high speed, quietly, and at low cost. Further, since no force is applied to the three-dimensional object, there is no need to add a support, and a three-dimensional object having a particularly complicated shape can be produced. Further, a soft and easily deformable material can be used. A three-dimensional object can be made without any steps on the surface.

According to the second aspect, a three-dimensional object can be produced at high speed and quietly.

According to the third aspect, the effect of the first aspect can be specifically realized.

According to the fourth aspect, it is not necessary to consider the scattering of ultrasonic waves accompanying the curing of the resin, and the configuration of the apparatus can be simplified.

According to the fifth aspect, a three-dimensional object can be produced at higher speed and with lower power consumption.

According to the sixth aspect, a three-dimensional object in which an arbitrary portion is colored can be produced.

According to the seventh aspect, a three-dimensional object can be produced with high accuracy.

According to the eighth aspect, a three-dimensional object can be produced with high accuracy.

According to the ninth aspect, a three-dimensional object in which a ready-made member is embedded can be produced.

According to the tenth aspect, the effect of the first aspect can be specifically used.

According to the eleventh aspect, the effect of the first aspect can be specifically realized.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a three-dimensional printing apparatus A according to the present invention.

FIG. 2 is a diagram showing a state in which a pressure wave transmitted from a focal point F reaches a plurality of vibrators T1 to Tn.

FIG. 3 is a diagram illustrating a state in which pressure waves transmitted from a plurality of vibrators T1 to Tn reach a focal point F.

FIG. 4 is a diagram showing a structure of a microcapsule M.

FIG. 5 is a diagram showing a procedure in which the three-dimensional printing apparatus A performs printing.

FIG. 6 is a diagram showing an example of a scanning path of a focal point F in which the inside of the three-dimensional object S is formed first and the surface is formed later.

FIG. 7 is a diagram showing a configuration of a three-dimensional printing apparatus Aa by a method of moving the vibrators T1 to Tn themselves.

[Explanation of symbols]

A: Solid modeling device, Aa: Solid modeling device, B1 ...
X direction moving device, B2 ... Y direction moving device, B3 ... Z direction moving device, C1 ... Path planning software, C2 ...
Ultrasonic oscillation circuit, C2a ... Ultrasonic oscillation circuit, C3 ...
Scanning mechanism driving circuit, D: three-dimensional shape data, D1: scanning path data, F: focal point, M: microcapsule,
M1 ... shell, M2 ... hardener, M3 ... air bubbles, MA
... Colored microcapsules, P1 ... Latent image generation step, P
2 ... curing reaction step, R ... resin, S ... three-dimensional object, T1
~ Tn ... shaker, U ... ultrasonic wave, VW ... water tank, VR
... resin tank, W ... water, X ... signal line.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Fuminobu Takahashi 7-2-1, Omika-cho, Hitachi City, Ibaraki Prefecture F-term in the Electric Power and Electric Power Development Laboratory, Hitachi, Ltd. 4F203 AB03 AB26 AP06 AP12 AR07 AR13 DA12 DB01 DC10 DF02 DJ06 DK10 DK14 DK16 DL19 4F213 AB03 AB26 AP06 AP12 AR07 AR13 WA25 WA40 WA53 WA87 WA92 WB01 WF02 WL08 WL15 WL25 WL67 WL75 WL95

Claims (11)

[Claims] 1. A means for holding a liquid material having a property of initiating hardening by vibration exceeding a certain intensity, a vibrator for generating a vibration field focusing inside the liquid material, and a three-dimensional object A three-dimensional object, comprising: path planning means for obtaining a path of a point at which the liquid material is to be cured from three-dimensional shape data describing the shape of the object; and scanning means for moving the focal point along the path. apparatus. 2. The three-dimensional molding apparatus according to claim 1, wherein the vibration is an ultrasonic vibration, and the scanning unit shifts the focal point by a method of changing a phase of the ultrasonic vibration generated by the plurality of vibrators. A three-dimensional molding device characterized by being moved. 3. The three-dimensional modeling apparatus according to claim 1, wherein a main component of the liquid material is a liquid resin incompletely polymerized, and the liquid material is broken by vibration exceeding a certain level, and 3. A three-dimensional modeling apparatus, comprising: a microcapsule having a property of releasing a substance contained in the microcapsule, wherein the microcapsule contains a substance having a property of initiating polymerization of the resin. 4. The three-dimensional molding apparatus according to claim 3, wherein a time from contacting the resin with the reaction initiator until polycondensation of the resin occurs is longer than a time required for scanning the focal point. A three-dimensional molding device characterized by the following. 5. The three-dimensional molding apparatus according to claim 3, wherein the microcapsules are air-containing microcapsules, and the vibrator generates vibration at a resonance frequency of the air-containing microcapsules. Modeling equipment. 6. The three-dimensional printing apparatus according to claim 3, wherein the liquid material contains an uncolored dye and a plurality of types of the microcapsules having different resonance frequencies. A three-dimensional modeling apparatus including a coloring agent having a property of coloring the dye therein, wherein the vibrator generates vibrations of a plurality of frequencies. 7. The three-dimensional molding apparatus according to claim 1, wherein the liquid material is a Bingham fluid. 8. The three-dimensional modeling apparatus according to claim 1, wherein the path planning unit generates the path for scanning the inside of the three-dimensional object first and the surface later. 9. The three-dimensional molding apparatus according to claim 1, further comprising: means for holding a member inside the liquid material. 10. A three-dimensional modeling method using the three-dimensional modeling device according to claim 1. 11. A three-dimensional structure material, which is the liquid material according to claim 3.