JP4131230B2 - Mold as stereolithography - Google Patents

Description

  The present invention relates to a mold formed as an optically shaped object, and particularly to a mold composed of a male mold and a female mold.

  There is a method of manufacturing a powder sintered part known as an optical modeling method. The manufacturing method disclosed in Japanese Patent No. 2620353 (Patent Document 1) and the like sinters a powder of a corresponding portion by irradiating a predetermined portion of the layer of the metal powder material to form a sintered layer. Then, a new layer of powder material is coated on the sintered layer, and a predetermined portion of the powder is irradiated with a light beam to sinter the powder at the corresponding location, so that a new one integrated with the lower sintered layer is obtained. By repeating the formation of the sintered layer, a powder sintered part in which a plurality of sintered layers are laminated and integrated is created, and a model that is the design data (CAD data) of the part to be obtained is created. Since the light beam is irradiated based on the cross-sectional shape data of each layer generated by slicing to a desired layer thickness, a so-called arbitrarily shaped powder sintered part can be easily obtained, and a manufacturing method by cutting or the like Compared to the desired shape quickly It can be obtained form thereof.

However, a model created by stereolithography tends to warp, and when this is used for a mold, there is a gap between the surface where the male mold and female mold contact in the direction in which the clamping pressure is applied, so-called parting surface. Will occur.
Japanese Patent No. 2620353

  The present invention has been invented in view of the above-described conventional problems, and an object of the present invention is to provide a mold as an optically shaped article that can solve the problem caused by warpage.

  In order to solve the above problems, the mold as an optically shaped object according to the present invention forms a sintered layer by irradiating a predetermined portion of the layer of the metal powder material with a light beam to sinter the powder at the corresponding portion. Then, a new layer of powder material is coated on the sintered layer, and a predetermined portion of the powder is irradiated with a light beam to sinter the powder at the corresponding location, so that a new one integrated with the lower sintered layer is obtained. A mold formed as an optically shaped object obtained by repeating the formation of a sintered layer, and a mold clamp is placed on the surface in contact with the other mold in a pair in the direction in which mold clamping pressure is applied or behind it. It has the characteristic that the deformation | transformation part which deform | transforms with the pressure of time is formed at the time of optical modeling. The warpage is absorbed by the deformation of the deformed portion due to the pressure during mold clamping.

  When a high-density part having a high density and a low-density part having a density lower than that of the high-density part are selectively formed, the deformed part is formed by a low-density part that is plastically deformed by pressure during clamping. Or a portion where the high-density portion is formed as a portion that is elastically deformed by the pressure at the time of clamping by facing the gap or the low-density portion in the clamping direction.

  According to the present invention, the problem of warping associated with an optically shaped object can be solved by density manipulation of a shaped object or a hollow structure that is possible because of optical modeling.

  Hereinafter, the present invention will be described based on an embodiment shown in the accompanying drawings. FIGS. 2 and 3 show an example of an apparatus for producing a powder sintered part by an optical shaping method, and a powder tank 26 provided with a lifting table 27. The metal powder material housed in 1 is supplied to the modeling tank 25 side by the squeezing blade 21 and the surface is smoothed to move up and down on the modeling stage, that is, in the space surrounded by the modeling tank 25 up and down. The powder layer forming means F for forming the powder layer 10 having a predetermined thickness on the lifting table 20 and the laser output from the laser oscillator 30 are applied to the powder layer 10 via a scanning optical system such as a galvano mirror 31. And a sintered layer forming means S that sinters the powder to form the sintered layer 11, and is connected to the base portion of the powder layer forming means F via the XY drive mechanism 40. And a cutting and removing device 4 provided with the over ring head 41.

  In the production of the sintered powder part, the powder material 10 is supplied to the surface of the modeling base 3 on the upper surface of the lifting table 20 and the first powder layer 10 is formed by smoothing with the blade 21. The portion to be cured is irradiated with a light beam (laser) L to sinter the powder to form a sintered layer 11 integrated with the base 3.

  Thereafter, the lifting table 20 is slightly lowered, the powder material is supplied again, and the blade 21 is used to form the second powder layer 10. A light beam (laser) is applied to the portion of the powder layer 10 to be cured. L is irradiated to sinter the powder to form the sintered layer 11 integrated with the lower sintered layer 11. The lifting table 20 is lowered to form a new powder layer 10. The desired powder sintered part is manufactured by repeating the process of irradiating and forming the required portion as the sintered layer 11.

  The irradiation path of the light beam is created in advance from the data of the three-dimensional CAD model of the powder sintered part to be obtained. That is, contour shape data of each cross section obtained by slicing STL data generated from a three-dimensional CAD model at an equal pitch (for example, 0.05 mm) is used. When irradiating with a light beam, the density of the powder-sintered part can be controlled by adjusting the energy intensity, operation speed, etc., but at least the outermost surface of the powder-sintered part has a high density (porosity of 5% or less) It is preferable to irradiate with a light beam that can be sintered.

  Then, the powder layer 10 is formed and the light beam is irradiated to form the sintered layer 11 repeatedly. The laminated thickness of the sintered layer 11 is, for example, the milling head in the cutting removal means 4. If the required value obtained from the cutting tool length 41 or the like is reached (after the lamination of the m layers is finished), the surface portion (including the side surface) of the powder sintered part formed so far by operating the cutting removal means 4 once. ). In addition, it does not have such a cutting removal means, and the thing which does not perform the cutting process in the middle of lamination | stacking may be used.

  FIG. 1 shows a pair of molds 1 and 2 created by an optical modeling method using the above manufacturing apparatus, and these molds 1 and 2 for molding a synthetic resin molded product are light beams at the time of optical modeling. By adjusting the energy intensity, the scanning speed, etc., the high density portion H and the low density portion L are selectively formed, and the surface is formed by the high density portion H as described above. Basically, in the molds 1 and 2 shown in FIG. 1, the low density portions L are formed on the surfaces that contact each other in the direction in which the clamping pressure is applied.

  The low density portion L located on the so-called parting surface P is plastically deformed by this pressure when a clamping pressure is applied if at least one of the pair of molds 1 and 2 is warped. The warping is absorbed and the parting surfaces P of the molds 1 and 2 are brought into close contact with each other. The entire parting surface P is not formed by the low density portion L, but the innermost peripheral portion is formed by the high density portion H in order to prevent resin leakage during resin molding. When the width of the cavity formed by both molds 1 and 2 is represented by e, the width f of the high-density portion H at the innermost peripheral part of the parting surface P is preferably about e + 1 mm. Depending on the size and structure of 2, the size may be further increased.

  As shown in FIG. 4, the low-density portion L that undergoes plastic deformation may be disposed behind a surface that contacts another mold in a pair in the direction in which the clamping pressure is applied. Although the parting surface P itself is formed by the high density portion H, if the clamping pressure is applied, the low density portion L located behind the part P will be crushed to absorb warpage. The surfaces consisting of the high density portions H in the parting surface P are in close contact with each other. In this case, if the low density portion L has a wedge shape whose thickness increases toward the outer periphery, the formation of the low density portion L causes warpage in the molds 1 and 2 to increase. The amount can be suppressed.

  In the case shown in FIG. 4, not only the parting surface P but also the so-called touch surface T is provided with a low density portion L that is plastically deformed behind, so that the other mold 2 is not affected by warpage. A close contact state is obtained with respect to 1. The low density portion L corresponding to the touch surface T is preferably provided only on one of the molds 1 and 2.

  By the way, the part which is plastically deformed by the clamping pressure can be obtained by forming the columnar part Q and the hollow part A at the time of optical modeling as shown in FIG. In addition, by appropriately adjusting the ratio of the columnar portion Q and the cavity portion A, the region where the columnar portion Q and the cavity portion A are present can be used as an elastic deformation portion described below. In FIG. 5, a low density portion L and a medium density portion M provided at the center of the mold 1 are provided for shortening the manufacturing time and reducing the weight of the mold 1 by optical modeling.

  FIG. 6 shows another example. This is because optical shaping is performed so that there is a portion where the high-density portion H is opposed to the gap in the direction in which the clamping pressure is applied, so that when the clamping pressure is applied, the other mold 2 that makes a pair. , 1 is made to elastically deform the high density portion H in contact with. When providing a gap leads to an increase in the amount of warpage generated in the mold 1, it is preferable to provide a support that connects the upper and lower opposing portions and collapses when pressure is applied during resin molding. The warp is suppressed by the support so that the support is not crushed during the resin molding and the elastic deformation of the mold 1 is not hindered. Even in this case, it is possible to obtain a state in which the warping in the molds 1 and 2 is absorbed and the parting surfaces P of both are in close contact.

  As shown in FIG. 7, the elastically deformable portion can also be obtained by performing optical modeling so that there is a portion where the high density portion H is opposed to the low density portion L in the direction in which the clamping pressure is applied. Moreover, an elastic deformation part can also be obtained by formation of the cavity part A and the columnar part Q as mentioned above.

  The part of the parting surface P that absorbs warp may be provided only in one of the molds, instead of being provided in both the pair of molds 1 and 2. Moreover, it is good also as what employ | adopted a different structure by the metal mold | dies 1 and 2 used as a pair. That is, one mold may be elastically deformed and the other mold may be absorbed by the plastically deformed section.

  In addition, when providing a plastic deformation part or an elastic deformation part, it is good also as what combined two or more structures shown in said each example.

It is sectional drawing of an example of embodiment of this invention. It is a schematic perspective view of an optical modeling apparatus same as the above. It is a schematic sectional drawing of an optical modeling apparatus same as the above. It is sectional drawing of another example. Furthermore, it is sectional drawing of another example. An example of another embodiment is shown, and both (a) and (b) are cross-sectional views. It is sectional drawing of another example.

Explanation of symbols

1 Mold 2 Mold H High density part M Medium density part L Low density part P Parting surface

Claims (3)

  By irradiating a predetermined portion of the layer of the metal powder material with a light beam, the powder at the corresponding portion is sintered to form a sintered layer, and a new layer of the powder material is coated on the sintered layer. Gold formed as an optically shaped object obtained by repeatedly irradiating a portion with a light beam to sinter the powder at the corresponding location to form a new sintered layer integrated with the lower sintered layer It is a mold and is characterized in that a deformed part that is deformed by the pressure at the time of mold clamping is formed at the time of stereolithography on the surface that contacts the other mold in a pair in the direction in which the mold clamping pressure is applied or behind it. Mold as an optical modeling object.   A high-density part having a high density and a low-density part having a density lower than that of the high-density part are selectively formed, and the deformed part is formed by a low-density part that is plastically deformed by the pressure during clamping. A mold as an optically shaped object characterized by   A high-density part having a high density and a low-density part having a density lower than that of the high-density part are selectively formed, and the deformed part has a high-density part via a gap or a low-density part in the mold clamping direction. The mold as an optically shaped object according to claim 1, wherein the mold is formed as a portion that is elastically deformed by a pressure at the time of mold clamping.

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