JP2012126059A - Device for manufacturing three dimensional object - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for manufacturing a three dimensional object made of a curable material, reliably operating while maintaining excellent sealing performance regardless of a highly viscous liquid material droplet having high kinetic energy.SOLUTION: The device includes at least one preparation unit (11) preparing the curable material to a liquid phase in order to discharge the curable material in the form of discontinuous droplets (15) in a direction toward a configuration space (17) from a material storage (12) via a discharge unit (13). A closing member has an elastically deformable solid coupling section (24), thereby meeting the general condition required for the discharge.

Description

  The present invention relates to an apparatus for manufacturing a three-dimensional object, and more particularly to an apparatus for manufacturing a three-dimensional object made of a curable material, as described in the superordinate conceptual part (front part) of claim 1. Such an apparatus is, in particular, an apparatus for producing a three-dimensional object composed of a curable material that is in a liquid phase or can be liquefied in the starting state by sequential ejection of drops of the material, At least one component space for building up the object, at least one preparation unit for preparing a curable material into a liquid phase, and an outlet opening with closing means capable of intermittently operating the curable material At least one material accumulator for the liquid phase, with at least one discharge unit for discharging in the form of non-continuous drops in a direction towards the component space, and the liquid in the material accumulator An apparatus having at least one pressure generating unit for generating pressure against the phase.

  In the production of plastic parts, it is known to manufacture parts on a large lot scale and in mass production by injection molding or extrusion molding. The advantages of plastic injection molding are mainly based on the high-precision production of complex parts (geometry) shapes, in which the functional diversity of the injection molding method is the optimal way, the inexpensive and economical of plastic parts Covers production requirements.

  At the same time, there is a demand for one-piece and small-lot plastic parts such as, for example, master parts (or sample parts) with very short supply requirements and characteristics similar to those of injection molded parts. Increasingly. In order to manufacture such a part, there is a manufacturing method widely known by the concept of prototyping. The production of such parts is often based on generating (geometric) shapes from 3D data. These (geometric) shapes can be produced in very different forms, for example by suitable means such as melting of the powder layer by means of heat introduction using a laser, or by production systems such as pressure methods in different ways of joining powder parts, Alternatively, it is also produced by a so-called melt extrusion molding method.

From Patent Document 1 which is the basis of the upper conceptual part of claim 1, a plasticizing unit known in the injection molding technology is connected to a material accumulator which is for the liquid phase of the material and can be put under pressure. A device is known. In order to produce an object on the object support in the construction space, the material is ejected in the form of drops through a discharge opening, with a high pressure and often a high temperature based on the adhesion of the material. Must also be added. In this case, the droplets have a size of 0.01 to 0.5 mm ³ . The opening time of the discharge nozzle (or discharge orifice) is preferably in the range of less than milliseconds and the diameter of the discharge opening is in the range of less than 1/10 millimeter.

  From US Pat. No. 6,057,056, a principle similar to inkjet printing is known, in which individual drops are produced from a material. Drop production is carried out using a known piezo transducer, in which the material is additionally supplied from a storage container “in a siphon” (or through a siphon). Therefore, the material that remains at the pressure head is not under pressure.

  One that operates on a principle similar to that described above is the method described in US Pat. Nos. 5,099,086 and 5,048, in which the photopolymer material is pressurized according to the principle of inkjet printing and subsequently exposed. There are many patent applications for this technology, and these patent applications are engaged in the configuration of the attached pressure head and the solution of problems that occur at that time (for example, Patent Documents 5 to 16). .

  The principle of how the best monodispersed droplets of the same particle size as possible can be generated by a piezoelectric vibration generator is described in particular in US Pat. Are listed. However, this is not in common with plastic technical drop generation.

  It should be noted that all the disclosed contents of the above Patent Documents 1 to 20 are incorporated and described in this document with reference thereto.

EP 1 886 793 A1 WO 95/05943 US 6,850,334 B1 US 6,658,314 B1 US 6,259,962 B1 WO 00/52624 A1 WO 00/76772 A1 WO 01/26023 A1 WO 01/53105 A2 WO 2004/044816 A1 WO 2004/050323 A1 WO 2004/096514 A2 WO 2004/096527 A2 WO 2005/053928 A2 EP 1 637 307 A2 DE 199 31 112 A1 DE 100 13 451 A1 DE 100 13 450 B4 DE 196 26 428 A1 DE 200 05 997 U1

  A material reservoir that is under high pressure and possibly at high temperature, as a minimum amount in discrete individual parts (or portions) until a highly viscous liquid material such as molten plastic falls below a few micrograms In the solution that is processed from (or material space), in particular, the released part can overcome the adhesion and has a high kinetic energy enough to leave the device and fly away as a drop. In such a case, there arises a problem of immediate sealing (or sealing).

  Starting from the above background art, the problem underlying the present invention is to create an apparatus for producing a three-dimensional object that operates reliably under the above conditions.

  According to one aspect of the present invention, the following apparatus is provided. The device is a device for producing a three-dimensional object composed of a curable material that is in a liquid phase or can be liquefied in the starting state by the sequential discharge of drops of the material, in order to make up the object At least one component space, at least one preparation unit for preparing the curable material into a liquid phase, and through the outlet opening with closing means capable of intermittently operating the curable material, said component space At least one material accumulator (or material space) for the liquid phase with at least one discharge unit for discharging in the form of non-continuous drops in the direction towards the liquid, and the liquid in the material accumulator An apparatus having at least one pressure generating unit for generating pressure against the phase. In the apparatus, the closing means has an elastically deformable solid connecting part (or a connecting structure (Festkoerpergelenk)). (Basic configuration: Form 1)

  According to the above basic configuration of the present invention, the effect corresponding to the above problem, that is, even when a droplet of a highly viscous liquid material has high kinetic energy, it has excellent hermeticity (or sealing function) and operates reliably. An apparatus for producing a three-dimensional object can be achieved. Furthermore, additional effects can be achieved for each of the following preferred embodiments in addition to the basic configuration.

In the following, preferred forms of the device according to the invention will be described. Each of the following forms also corresponds to each constituent element described in the claims of the present application.
(Mode 1) As in the above basic configuration.
(Mode 2) It is preferable that the outlet opening can be closed by a nozzle needle of the closing means, and the nozzle needle is coupled to a support portion of the nozzle needle through the solid connecting portion.
(Mode 3) It is preferable that the solid connecting portion is simultaneously formed as a sealing means for the material accumulator.
(Mode 4) It is preferable that the nozzle needle can be operated only in one direction via an actuator, and the actuator is disposed apart from the material accumulator.
(Mode 5) It is preferable that the position of the actuator can be adjusted manually or in a controlled manner in a pre-tension state.
(Mode 6) Preferably, a sensor mechanism is provided, and a signal of the sensor mechanism re-adjusts the position of the actuator according to the operating conditions in the material accumulator.
(Mode 7) The actuator is preferably formed as a force measuring element in order to measure and readjust the pretension state of the solid connecting portion at the operating point.
(Mode 8) The actuator is preferably a piezo element.
(Embodiment 9) An adjustment and control device for detecting a signal of the sensor mechanism and / or the force measuring element is provided, and a setting value for the actuator can be determined based on the detected signal Or it is preferable that it can prescribe | regulate.
(Mode 10) It is preferable that a surface receiving the pressure in the material accumulator or the outflow passage of the material accumulator is larger on the opposite side of the outlet opening than in the range of the outlet opening.
(Form 11) It is preferable that the preparation unit forms the material accumulator at the same time.
(Form 12) The preparation unit is a plasticization unit known in injection molding technology for preparing a curable material as a plasticized material or a plasticizable material, the material being a liquid Having a so-called front laminar flow in the phase, and the plasticizing unit is connected to take the liquid phase of the material into the material accumulator and the material accumulator which can be under pressure It is preferable.
(Mode 13) It is preferable that the actuator is insulated from the material accumulator.

  Under the above-mentioned conditions, the discharge device according to the present invention has as few sealed parts (or sealing parts) as possible with respect to the outside as a metering unit. For this reason, the closing means has an elastically deformable solid connection. Thereby, the closing means, preferably formed as a nozzle needle, is operable on the one hand, and on the other hand the actuator is not exposed to the harsh conditions inside the material accumulator. Thus, no additional sealing is required other than the filling opening of the material reservoir and the filling opening of the discharge nozzle (or discharge orifice). In addition, the solid coupling part, due to its appropriate (geometric) three-dimensional configuration, provides a quasi integriert restoring force (based on the elasticity of the solid coupling part) to the actuator acting from the outside. Thus, the connection of the actuator to the material accumulator (or material space) is made with minimal contact surface and einseitig for force action.

  Hereinafter, preferred embodiments illustrated in the drawings will be described in detail.

FIG. 2 is a partial cross-sectional side view of one embodiment of an apparatus according to the present invention. FIG. 2 is an enlarged sectional view of FIG. 1 in the range of the discharge unit. It is sectional drawing and three-dimensional figure of a closure means. FIG. 3 shows the discharge unit according to FIG. 2 connected to an attached control device.

  Before describing the embodiments of the present invention in detail, it is added that the present invention is not limited to each component and each method step of the apparatus shown in the following embodiments. This is because those components and methods can be changed. Also, the concepts used here are defined specifically to illustrate the embodiments and are not to be treated as limitations. That is, the following examples are for facilitating the understanding of the present invention, and within the scope of the technical idea of the present invention, additions, substitutions, and disclosed elements that can be implemented by those skilled in the art. It is not intended to exclude the selection or selective combination. Further, the description of the constituent members in the present specification and the claims of the present application includes both the singular and plural meanings unless there is a specific expression. It should be noted that the reference numerals in the drawings attached to the claims of the present application are only for facilitating the understanding of the present invention, and the present invention is not limited to the following embodiments. .

  FIG. 1 shows an apparatus for producing a three-dimensional object 16 made of a curable material that is in a liquid phase or can be liquefied in the starting state by sequential ejection of drops of the material. . For example, this can be done by discontinuous individual drops 15 (FIG. 2) from the discharge unit 13 until the three-dimensional object or object 16 is obtained layer by layer on the object support 14 in the configuration space 17. This is done by sequentially releasing. The curable material may be a plasticized material such as silicone (resin), a plasticizable material such as plastic, or a powdered material, where the curable material is the starting material. In the present invention, it is essential to be in a fluid state, typically in a liquid phase or in a state where it can be liquefied. The material can be reversibly melted by heat, and thus can be a reusable (or recyclable) material. Any other material can be used as long as the material is plasticizable, in particular as long as it can be released by at least one discharge unit 13.

  The curable material has a so-called laminarer Quellfluss in the liquid phase. The adhesion portion of the melt particularly in the wall portion enters the front laminar flow. This becomes most apparent with a glance at the perception of injection molding technology. During mold filling of a simple rectangular channel, the melt is injected via a so-called inlet, and from this point it begins to expand into a circular shape with a closed flow front (Fliessfronten) and fills the full width of the cavity To. After some time thereafter, it can be seen that the space between the inflow part and the flow front is almost filled (and formed). The flow front itself has a special flow situation, i.e. "front laminar flow", because streamlines in this range appear as aquatic (Quelle) when viewed with respect to the co-ordinated coordinate system. . The melt flows in the area between the two material layers (or mass layers) that are close to the cavity surface and immediately solidify, with the melt moving toward the flow front at a higher velocity in the center of the cavity. And proceed. Immediately before the melt reaches the flow front, the velocity component in the flow direction decreases, and the melt flows obliquely with respect to the wall and hits the wall.

The front laminar flow is on the one hand advantageous for the production of droplets 15 "oriented" on the constituent space 17 on the one hand, on the other hand, especially here when forming small droplets, injection molding. There is the problem of making recombination using equipment and materials known from the art difficult. That is, it is difficult for the material (or mass) to form a drop having a desired small volume in the range equal to or smaller than 1 mm ³ and a desired scattering rate, or a mass (or mass). On the other hand, proper high viscosity of the material is just important to form the proper drop shape in non-continuous drops.

This also distinguishes the materials used from known waxes (or waxes). The wax material is based on its viscosity and is dissipated in the usual thermal printing or injection processes, i.e. by purely kinematic pressureless acceleration without the pressure difference of the molten drops. The materials used here are already distinguished here by their viscosity number being higher by a power of 10 to a multiple of 10 (10 ¹ to 10 ⁿ ). That is, the dynamic viscosity number of the curable material is between 100 Pa and 10,000 Pa, where the curable material is preferably a plastic or resin customary in injection molding technology. This requires treatment from a material accumulator that can be put under pressure, because pressures from greater than 10 MPa up to 100 MPa (100-1000 bar), especially for small drop volumes. This is because it is essential anyway if a small discharge opening is used to achieve.

Preferably, the desired volume of droplet 15, in particular in the range of 0.01 to 0.5 mm ^3, preferably in the range of 0.05 to 0.3 mm ^3, and particularly preferably of approximately 0.1 mm ³ range. The diameter of the outlet opening 20 is in particular equal to or smaller than 1 mm, preferably approximately 0.1 mm. A conventional injection speed of 100 cm / s, which feeds material (or mass) through a so-called Punktanguss having a diameter of 0.1 mm, gives a value of 10,000 m / s in volumetric flow by the surface. This leads to a front laminar flow with a flow rate up to 10,000 m / s for the liquid phase.

  This device uses the discharge unit of this device to store highly viscous liquid material such as molten plastic under a high pressure and possibly even a high temperature as a minimum amount to below a few micrograms. It has a role to discharge from the vessel 12. The minimum amount of material / drop 15 is dissipated as discrete individual parts (or portions), the size of which can be influenced by the device. The ejected part can overcome adhesion and fly away as a drop 15 as the part builds up the object 16 on the object support 14 in the configuration space 17. Has a high kinetic energy.

  Because of its high adhesion and low weight, liquid but highly viscous material, its kinetic energy is between the material accumulator 12 and the splash space for the drops 15 formed in the component space 17. It is conveyed using the pressure difference. The subdivision or partialization (or portioning) into droplets is performed using an intermittently operated nozzle (or orifice) having a nozzle needle 21 as a closing means. Due to the required dimensions of the part and also due to its viscous properties, pressures in the range of 100 MPa (1000 bar) or more as usual, closed nozzles (or closed orifices) smaller than 0.1 mm, and more than 0.001 s A short closure time is required. Since the material is often plastic, the temperature in the material accumulator 12 reaches 450 ° C.

  Under the above conditions, the device must be realized as a metering unit with as few sealed / contacting parts as possible with respect to the outside world. For this purpose, a closing means having an elastically deformable solid connecting part 24 is formed in accordance with FIGS. In particular, the cross-sectional view of FIG. 3 shows that the solid connecting portion 24 is a thin-walled portion formed in a ring shape so as to have flexibility, and is fixed in the meaning of a material bridge that connects the nozzle needle 21 and the ring-shaped support portion 21a. On the other hand, it shows that the fixed connection portion is in a state of being elastically operated like a spring appropriately and elastically by the actuator 26. As the closing means, a nozzle needle 21 having a support portion 21a is used. On the side of the central nozzle needle 21, the material of the nozzle needle 21 is thinned to form the solid connecting portion 24. On the opposite side of the nozzle needle 21, the actuator 26 engages (or abuts) directly or via an intermediate element on the abutment surface 21b. A ring-shaped recess 21c is formed on the opposite side of the contact surface 21b. In FIG. 3, the solid connecting portion 24 is disposed almost in the middle of the support portion 21 a in the axial direction of the nozzle needle 21 as a preferable arrangement location. However, the position of the solid connecting portion 24 in the axial direction of the nozzle needle 21 is not limited to that position, and may be an upper side or a lower side. The closing mechanism closes the discharge nozzle (or discharge orifice) 27 using the nozzle needle 21.

  At least one preparation unit is provided for preparing a curable material into a liquid phase, from which the conditioned material is provided with at least one discharge unit 13 12 is reached. The material is discharged from the discharge unit 13 in the form of non-continuous drops (or drops) 15 in the direction towards the component space 17 through an outlet opening 20 with intermittently actuable closing means. In order to ensure the necessary boundary conditions, a pressure generating unit is provided in the material accumulator 12 for generating pressure on the liquid phase. The material accumulator 12 may be part of the preparation unit 11 formed by a plasticizing unit, as in this example. At this time, the pressure generating unit is configured, for example, as the transport worm 28 shown in FIG. 1 or similar transport means.

  The nozzle needle 21 suspends directly (as an integral member) on a resilient solid connection 24, which faces the material reservoir 12 for the liquid phase of the material outward ( Closed with respect to the actuator 26 for operation. Therefore, a separate sealing portion (or sealing portion) other than the filling opening of the material accumulator 12 and the filling opening of the discharge nozzle 27 is unnecessary. Due to its appropriate (geometric) three-dimensional configuration, the solid connecting portion 24 has a substantially integral restoring force (based on the elasticity of the solid connecting portion 24) with respect to the actuator 26 acting on the contact surface 21b on the outside. Thus, the connection of the actuator 26 to the material accumulator 12 under high pressure and high temperature is made in a unidirectional manner with minimal contact surface and with respect to force action.

  At the same time, the solid connection 24 is used as a sealing means for the material accumulator 12 in the direction towards the actuator 26, via which the nozzle needle 21 according to FIG. 2 can be operated in only one direction (einseitig). is there. The actuator 26 is preferably insulated from the material reservoir 12 by an insulating element and is spaced apart from the material reservoir 12, as suggested in FIG.

  The solid connecting part 24 formed as described above can take various forms of (geometric) three-dimensional configuration, for example, the discharge nozzle 27 is passively (or driven) closed or It can be formed with a pre-tension so that it is passively open. Moreover, the solid connection part 24 can be manufactured from arbitrary materials of pressure | voltage resistance heat resistance, This material is not restricted to a metal, For example, the lightweight structural material reinforced with the fiber may be sufficient. The surface of the material accumulator 12 or the material accumulator 12 that receives the pressure in the outflow passage 12 b is larger on the opposite side of the outlet opening 20 than in the area of the outlet opening 20. Under the configuration described above, the nozzle needle 21 can be opened passively. This means that the actuator 26 actively pushes and closes the outlet opening 20, and the new outlet opening 20 opens due to de-energization of the actuator 26. That is, the nozzle needle 21 can be driven open or closed by driving the actuator 26.

  The actuator 26 can be formed as a rotor exhaust, a direct magnet, or a piezo element. Preferably, the actuator 26 is positionable manually or controlled under pre-tension. Similarly, according to FIG. 4, a sensor mechanism 19 can be provided, and the signal of the sensor mechanism 19 re-adjusts the position of the actuator 26 according to the operating conditions in the material accumulator 12, and thus to the operating point. Necessary for compensation based on high pressure and high temperature expansion. According to FIG. 4, for example, the force in the operating element is detected and readjusted to the force target value via the control device 18 and the regulator 22. Therefore, the pretension of the solid connecting portion 24 can be readjusted according to the operating conditions in the material accumulator 12 by using an automatic actuator position adjustment function by an appropriate pressure sensor and temperature sensor in the material accumulator 12. Is possible.

  To that end, the actuator 26 is preferably formed as a force measuring element in order to measure and readjust the pretension of the solid connection 24 at the operating point. Advantageously, the actuator 26 is a piezo element. Using this type of sensor mechanism 19 and controller 18, a target is set and actuated according to the stroke / force curve in the solid connection 24 using an actuator 26, thereby setting the target and consciously, for example in the form of a drop. It is also possible to influence the shape of the material to be released.

  It should be noted that the examples and the embodiments can be changed and adjusted within the scope of the entire disclosure (including claims and drawings) of the present invention and based on the basic technical concept. In addition, various combinations or selections of various disclosed elements are possible within the scope of the claims of the present invention. That is, the present invention naturally includes various modifications and changes that could be made by those skilled in the art according to the entire disclosure including the claims and the drawings, and the technical idea.

11 Preparation Unit 12 Material Accumulator 12b Outlet Passage 13 Discharge Unit 14 Object Support 15 Material Drop 16 Three-dimensional Object (or Object)
17 Configuration space 18 Control device 19 Sensor mechanism 20 Exit opening 21 Nozzle needle 21a Bearing 21b Contact surface 21c for actuator 26 Recess 22 Regulator 24 Solid connection (Festkoerpergelenk)
25 Insulating element 26 Actuator 27 Discharge nozzle (or discharge orifice)
28 Transport worm

Claims (13)

An apparatus for producing a three-dimensional object composed of a curable material that is in a liquid phase or can be liquefied in a starting state by sequential ejection of drops of the material,
-At least one component space (17) for making up said object (16);
-At least one preparation unit (11) for preparing the curable material into a liquid phase;
At least for releasing the curable material in the form of non-continuous drops (15) in the direction towards the component space (17) through the outlet opening (20) with closing means which can be actuated intermittently; At least one material accumulator (12) for the liquid phase with one discharge unit (13);
In an apparatus comprising at least one pressure generating unit for generating pressure on the liquid phase in the material accumulator (12),
The closure means comprises an elastically deformable solid connection (24). The outlet opening (20) can be closed by a nozzle needle (21) of the closing means, and the nozzle needle (21) is supported by the nozzle needle (21) via the solid connecting part (24). Device according to claim 1, characterized in that it is coupled to the part (21a). Device according to claim 1 or 2, characterized in that the solid connection (24) is simultaneously formed as a sealing means for the material accumulator (12). The nozzle needle (21) can be operated in only one direction via an actuator (26), and the actuator (26) is disposed away from the material accumulator (12). The device according to claim 1, characterized in that it is characterized in that The device according to claim 4, characterized in that the actuator (26) can be adjusted manually or in a controlled manner in a pre-tensioned state. A sensor mechanism (19) is provided, and the signal of the sensor mechanism (19) re-adjusts the position of the actuator (26) according to the operating conditions in the material accumulator (12). The apparatus according to claim 4 or 5. The actuator (26) is formed as a force measuring element for measuring and re-adjusting the pre-tension state of the solid connection (24) at the operating point. The apparatus as described in any one of. Device according to any one of claims 4 to 7, characterized in that the actuator (26) is a piezo element. An adjustment and control device (18) for detecting a signal of the sensor mechanism (19) and / or the force measuring element is provided and for the actuator (26) based on the detected signal 9. A device according to any one of claims 6 to 8, characterized in that the set value can be determined or defined. The surface receiving the pressure in the material accumulator (12) or the outflow passage (12b) of the material accumulator (12) is within the range of the outlet opening (20) on the opposite side of the outlet opening (20). The device according to claim 1, wherein the device is larger than Device according to any one of the preceding claims, characterized in that the preparation unit (11) forms the material accumulator (12) at the same time. The preparation unit (11) is a plasticizing unit for preparing a curable material as a plasticized material or a plasticizable material, the material having a front laminar flow in the liquid phase; And the plasticizing unit is connected to the material reservoir (12), which can be under pressure, and connected to take the liquid phase of the material into the material reservoir (12). The device according to any one of claims 1 to 11. Device according to any one of claims 4 to 12, characterized in that the actuator (26) is insulated from the material accumulator (12).

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