JP4661551B2 - Three-dimensional shaped object manufacturing equipment - Google Patents

Description

  The present invention relates to a three-dimensional shaped article manufacturing apparatus for forming a desired three-dimensional shaped article by irradiating a powder layer with a light beam to form a sintered layer and laminating the sintered layer.

  When manufacturing a three-dimensional shaped object from an inorganic or organic powder material, the powder layer formed on the stage is irradiated with a light beam (directed energy beam, for example, a laser) to form a sintered layer, and this sintering Form a new powder layer on the layer and irradiate with a light beam to form a sintered layer, and then laminate the sintered layer to produce a three-dimensional shaped object and sinter Japanese Patent Application Laid-Open No. 2002-115004 (Patent Document 1) shows that a finishing process of a surface of a model as a laminate of sintered layers is gradually performed in the course of manufacturing a three-dimensional modeled model by stacking layers. Yes.

  In order to manufacture a three-dimensional shaped object by the above manufacturing method, a modeling part provided with a modeling stage and a powder supply part for forming a powder layer by supplying powder to the modeling part, a modeling part Optical equipment for irradiating a light beam and a processing machine for finishing processing are necessary, but since a model is manufactured in a state where these are organically combined, a conventional manufacturing apparatus has a modeling part. In addition, a dedicated processing machine is installed in a modeling machine having a powder supply unit and an optical device.

In this case, since the entire apparatus has a dedicated configuration, the cost is inevitably increased, and the price of the three-dimensional shaped object to be manufactured is also increased.
JP 2002-115004 A

  This invention is invented in view of said conventional problem, Comprising: It aims at providing a low-cost three-dimensional molded object manufacturing apparatus.

Therefore, the three-dimensional shaped article manufacturing apparatus according to the present invention includes a modeling unit having a modeling stage and a powder supply unit for supplying powder to the modeling unit to form a powder layer. An optical device for irradiating a light beam to the modeling part to sinter powder at a predetermined position of the powder layer, and finishing the surface of the model as a laminate of the sintered layer at least during modeling A three-dimensional shaped article manufacturing apparatus configured with a processing machine, wherein the processing machine is a general-purpose numerically controlled machine tool capable of controlling at least three axes, and the modeling machine is set on a table in the processing machine, the optical device has the particular feature is detachably attached to the spindle stock in the machine. A general-purpose numerically controlled machine tool can be used , especially because it is detachably attached to the headstock of a processing machine, so that the adjustment of the spot diameter of the light beam for sintering can be adjusted. It is something that can be done by .

It is also preferred that Ru is interposed vibration-absorbing material between said headstock and said optics.

  It is preferable that the modeling machine is detachably mounted on a table in the processing machine. It is possible to easily use the processing machine for other purposes.

The molding machine has a sealed structure that enables sintering in an inert atmosphere and is equipped with a lid that can be opened and closed for processing by the processing machine, which ensures stable sintering by securing the atmosphere during sintering. At the same time, it is preferable in that it can be finished without problems.

  In addition, if the optical device has an oscillation unit that emits a light beam and a scanning optical system unit separated from each other and are connected by an optical fiber, the degree of freedom in arrangement increases and the oscillation unit vibrates. It can be installed in a place that is not affected by

Since the present invention can use a general-purpose numerically controlled machine tool, the apparatus cost can be reduced, and therefore the cost of the manufactured three-dimensional shaped object can also be reduced. Moreover, since it is detachably attached to the spindle stock in the processing machine, the adjustment of the spot diameter of the light beam for sintering can be performed by moving the spindle stock.

  Hereinafter, the present invention will be described in detail based on an example of an embodiment. The three-dimensional shaped article manufacturing apparatus shown in FIG. 1 supplies a powder to the modeling part 10 provided with a modeling stage 11 and the modeling part 10. And a powder forming unit 1 for forming a powder layer, an optical device 2 for irradiating the modeling unit 10 with a light beam, and a processing machine 3 for finishing. However, the processing machine 3 here is a general-purpose numerically controlled machine tool including a table (machining table) 30 and a spindle head 31 capable of controlling at least three axes. An end mill 33 for finishing is set. The modeling machine 1 is set on a table 30, and the optical device 2 is set on a spindle stock 31.

FIG. 2 shows an example of the modeling machine 1 used here, which is configured as the modeling unit 10 and the powder supply unit 13 housed in a sealable casing 18. The modeling unit 10 includes a stage 11 that can be moved up and down, and a powder supply unit 13 includes a powder tank 14 that stores powder, an elevating table 15 that is arranged to be movable up and down in the powder tank 14, and powder. It is formed of a squeezing blade 16 that supplies and smoothes the powder in the tank 14 to the modeling unit 10 side. In addition, an excess powder recovery unit 17 is provided in the casing 18.

  Further, the casing 18 is provided with a lid 19 whose upper surface is opened and closed by a driving mechanism 40 such as a cylinder or a solenoid as shown in FIG. A window 190 that transmits the beam is provided. In the figure, 180 is a packing for sealing the lid 19. Note that transparent glass may be used for the window 190 when the light beam is a YAG laser. However, when the light beam is a carbon dioxide gas laser, one made of ZnSe is used.

  The powder supply unit 13 supplies the uppermost powder pushed up by the lifting table 15 rising in the modeling tank 14 to the modeling unit 10 side when the blade 16 slides to the modeling unit 10 side. Further, the powder on the modeling part 10 is leveled by the blade 16 to form a powder layer having a predetermined thickness on the modeling part 10.

  The optical device 2 attached to the side surface of the headstock 31 projects the laser beam output from the laser oscillator through a scanning optical system such as a beam shape correcting means and a galvanometer mirror, and the powder in the modeling unit 10 through the window 190. Irradiate the layer. Of course, an optical system corresponding to the wavelength of the laser used is used.

  The three-dimensional shaped object is manufactured by using a blade that is filled with an inert gas (nitrogen) in a sealed casing 18 with the lid 19 closed, and the powder overflowed from the powder tank 14 on the upper surface of the stage 11 is bladed. The first powder layer is formed by leveling with the blade 16 at the same time as the supply with the laser 16, and the laser L from the optical device 2 positioned above the modeling part 10 as shown in FIG. The sintered layer 5 is formed by irradiating a portion of the powder layer to be cured and sintering the powder.

  Thereafter, the stage 11 is lowered by a predetermined amount, and the powder is supplied again and leveled by the blade 16 to form a second powder layer on the first powder layer (and the sintered layer). The portion of the second powder layer to be cured is irradiated with laser L to sinter the powder to form the sintered layer 5 integrated with the lower sintered layer 5.

  By lowering the stage 11 to form a new powder layer and irradiating a laser to make the required portion a sintered layer, a desired three-dimensional shaped object is obtained as a laminate of the sintered layers 5. A carbon dioxide laser can be suitably used as the light beam, and the thickness of the powder layer is 0.05 mm when the obtained three-dimensional shaped product is used for a molding die or the like. It is preferable to set the degree.

The irradiation path (hatching path) of the light beam is created in advance from three-dimensional CAD data. That is, the contour shape data of each cross section obtained by slicing the STL data generated from the three-dimensional CAD model at an equal pitch (0.05 mm when the thickness of the powder layer is 0.05 mm) is used. At this time, irradiation with a light beam is performed so that at least the outermost surface of the three-dimensional shaped object can be sintered at a high density (porosity of 5% or less), and the inside is baked to a low density. In other words, the shape model data is preliminarily divided into the surface layer part and the inside, and the inside is a sintering condition that becomes porous, and the surface layer part is a condition that the powder almost melts and becomes high density By irradiating with a light beam, a shaped object having a dense surface can be obtained at high speed.

  Then, the powder layer is formed and the sintered layer 5 is repeatedly formed by irradiating the light beam. The total thickness of the sintered layer 5 is, for example, the tool length of the end mill 33 in the processing machine 3. If the required value obtained from the above is obtained, the end mill 33 is positioned above the modeling unit 10 as shown in FIG. 1A and the lid 19 is opened. Cut the surface (mainly the upper side). For example, if the tool of the end mill 33 (ball end mill) is capable of cutting with a diameter of 1 mm, an effective blade length of 3 mm, and a depth of 3 mm, and the powder layer thickness is 0.05 mm, 60 sintered layers 5 The end mill 33 is actuated at the time when is formed.

  By cutting and finishing by this processing machine 3, the excessively hardened portion due to the powder adhering to the surface of the modeled object is removed, and at the same time, the high-density part is completely exposed on the surface of the modeled object by cutting into the high-density part it can. When this processing is completed, the lid 19 is closed, the casing 18 is filled with an inert gas, and the formation and sintering of the powder layer are repeated again.

  The cutting path by the processing machine 3 is created in advance from three-dimensional CAD data in the same manner as the laser L irradiation path. At this time, contour processing is applied to determine the machining path, but the Z-direction (vertical direction) pitch does not need to stick to the lamination pitch during sintering, and in the case of a gentle slope, the Z-direction pitch is made finer and interpolated. So that a smooth surface can be obtained.

  FIG. 4 shows a flowchart of the above process, and FIGS. 5A and 5B show a flowchart of the sintering preparation process and the cutting preparation process in FIG.

Here, the processing machine 3 is a general-purpose numerical machine tool as described above, and since it is configured with the modeling machine 1 and the optical device 2 added thereto, it already has a numerical machine tool. In terms of hardware, it is only necessary to introduce the modeling machine 1 and the optical device 2, and even if a numerical machine tool is newly introduced, it is fixed on the table 30 with a fixture 39 such as a bolt and nut. If the modeling machine 1 is removed, the processing machine 3 can be used for manufacturing other products by itself, which is also advantageous in terms of cost. Therefore, it is desirable that the modeling machine 1 can be easily attached to and detached from the table 30.

  Further, in the illustrated example in which the optical device 2 is attached to the spindle stock 31, the optical device 2 can be moved in the vertical direction, so that the spot diameter on the processing surface of the laser L can be adjusted.

  In attaching the optical device 2 to the head stock 31, it is also preferable that the optical device 2 can be easily attached and detached. FIG. 6 shows an example of this case. Connecting portions 51 and 52 having tapered lead-in portions are provided on the head stock 31 and the optical device 2 side, and are chucked by the claws 53, so that the optical device 2 It can be installed. It may be fixed using electromagnetic force. Whatever connecting means is used, it is preferable that a vibration absorbing material 54 such as a vibration absorbing sheet is interposed between the optical device 2 and the head stock 31.

  Further, as shown in FIG. 7, the optical device 2 may be attached in place of the tool (end mill 33) using a collet chuck for fixing the tool in the spindle head 32 of the head stock 31. The headstock 31 can be placed at substantially the same position during laser irradiation and during processing, and the total movement range of the main spindle 31 can be reduced as compared with the case where the engineering equipment 2 is mounted on the side surface of the headstock 31, A relatively large model can be produced.

FIG. 8 shows another example. This is because in the processing machine 3 provided with an XY-driven movable table 35 by an actuator on a table 30 (or base), the modeling machine 1 is installed on the movable table 35 and the optical system is mounted on a support column standing from the processing machine 3. The apparatus 2 is arranged, and the headstock 31 in this case may be movable only in the vertical axis direction because the movable table 35 side has a degree of freedom about two axes XY.

Then, as shown in FIG. 8 (b) by the movable table 35 at the time of sintering by laser L, moving the shaping part 10 of the molding machine 1 to the lower side of the optical device 2, the shaped portion 10 immediately below the headstock 31 during processing Move.

In this case, since it is necessary to match the laser scan coordinate system and the cutting coordinate system of the processing machine 3, it is preferable to match the axial direction of both coordinate systems and the movement axis direction of the modeling machine 1. Further, in order to simplify the coordinate axis alignment, the optical device 2 is set via a precision table (preferably capable of rotating around the XYZ and Z axes) for finely adjusting the arrangement position of the optical device 2. It may be left.

The optical device 2 may be attached to the housing 18 in the modeling machine 1 as shown in FIG. In this case, the optical device 2 can be slid from the position directly above the modeling unit 10 or rotated and moved away as shown in FIG. 10 so that the optical device 2 does not get in the way during processing by the processing machine 3. Keep it available. In FIG. 10, reference numeral 56 denotes a rotating shaft for rotational movement of the optical apparatus 2, and 57 denotes an inert gas filling port.

In the illustrated example, the modeling machine 1 with the optical device 2 is set on the movable table 35, but the modeling machine 1 with the optical device 2 may be set on the table 30 shown in FIG. Of course.

  Further, as shown in FIG. 11, the optical device 2 may be one in which the laser oscillator 21 and the optical unit 22 of the scanning optical system are separated and both are connected by an optical fiber 23. In this case, since the portion to be disposed above the modeling portion 10 in the optical device 2 is only the optical system unit 22 and the laser oscillator 21 can be installed in another location, the one shown in FIGS. 9 and 10 is used. Thus, in the case where the optical device 2 has to be moved away during processing by the processing machine 3, the distance that must be moved can be reduced. The optical fiber 23 is made of an appropriate material according to the type of laser used, like the window 190.

(a) (b) is a schematic sectional drawing of an example of embodiment of this invention. (a) and (b) are a schematic cross-sectional view of the above-described modeling machine and a plan view with a lid removed. It is a schematic sectional drawing which shows the opening / closing structure of the lid | cover in a modeling machine same as the above. It is a flowchart same as the above. (a) (b) is a flowchart of a sintering preparatory process and a cutting preparatory process same as the above. (a) and (b) are the schematic sectional drawing and an expanded sectional view of an optical equipment attachment part. (a) (b) is a schematic sectional drawing of another example. (a) (b) is a schematic sectional drawing of an example of other embodiment. (a) (b) is a schematic sectional drawing of an example of another embodiment. (a) (b) is a schematic sectional drawing of the other example same as the above. It is a block diagram of the other example of the optical apparatus same as the above.

Explanation of symbols

1 Modeling machine 2 Optical equipment 3 Processing machine

Claims (5)

A modeling machine having a modeling part provided with a modeling stage and a powder supply part for supplying powder to the modeling part to form a powder layer, and irradiating the modeling part with a light beam to form a powder layer This is a three-dimensional shaped article manufacturing apparatus composed of an optical device for sintering the powder at a predetermined location, and a processing machine that performs at least the finishing process on the surface of the molded article as a laminate of sintered layers. Te, the machine is a numerically controlled machine tool at least 3-axis control general purpose, the shaping device is set on a table in the machine, the optical instrument removably attached to the headstock in the machine A three-dimensional shaped article manufacturing apparatus characterized by being made. 2. The three-dimensional shaped article manufacturing apparatus according to claim 1, wherein a vibration absorbing material is interposed between the optical device and the headstock . The three-dimensional shaped article manufacturing apparatus according to claim 1 or 2, wherein the modeling machine is detachably mounted on a table in the processing machine . 4. The molding machine according to any one of claims 1 to 3, wherein the modeling machine has a sealed structure that enables sintering in an inert atmosphere and includes a lid that can be opened and closed for processing by the processing machine. The three-dimensional shaped article manufacturing apparatus described. 5. The optical device according to claim 1, wherein an oscillation unit that emits a light beam and a scanning optical system unit are separated and both are connected by an optical fiber. 6. 3D shaped object manufacturing equipment.

Images