JP2010202419A - Member for molding element, method for producing the element, and the element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide members for molding an element, which can suppress occurrence of damage of constituent elements such as an intermediate die and can mold a plurality of elements at a time and to provide a method for producing the element by using the members for molding the element and the element formed by using the members for molding the element. <P>SOLUTION: The members 10 for molding the element have a plurality of layered constituent elements to be layered/arranged. The layered constituent elements comprise a pair of dies (an upper die 1 and a lower die 2) for molding, a hollow barrel die 4 arranged to surround the outer peripheral surface of the upper die 1 and the lower die 2, a pressing member 5 which is connected to the upper die 1 being one of the pair of dies and used for pressing the upper die 1 along the inner peripheral surface of the barrel die 4 in the major axis direction of the barrel die 4, and a frame die 6 for adjusting the position of a base stock 3 for forming the element between the upper die 1 and the lower die 2. The pressing member 5 includes a restriction part 5a. The layered constituent elements are layered along the major axis direction of the barrel die 4. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an element molding member for molding an optical element such as a glass lens, an element manufacturing method and an element using the element molding member, and more specifically, a plurality of elements. Element forming member capable of forming at one time and suppressing inclination of each component of element forming member, element manufacturing method using element forming member, element using element forming member It is about.

  For example, aspherical lenses and diffractive lenses are used as optical elements used in various optical devices and optical communication devices such as digital cameras, far-infrared cameras, and mobile phones in order to meet the demand for higher performance. . Since it is very costly to manufacture an aspherical lens or a diffractive lens by polishing, it is mainstream to perform molding using an element molding member.

  In the technology of molding an element such as an optical element by molding, the mold and the material are heated in a state where a material to be an element is placed inside a pair of molds for molding among the element molding members. Then, the material is deformed by pressurizing the mold in a state where the predetermined temperature is reached. For example, in Japanese Patent Application Laid-Open No. 1-176240 (hereinafter referred to as “Patent Document 1”), a surface for transferring the shape of an element (lens) to be molded onto a material is sandwiched between a pair of upper and lower molds. An intermediate mold is provided, and includes a pair of upper and lower molds and an intermediate mold that slide along the inner peripheral surface of the cylinder mold in the longitudinal direction of the cylinder mold having a cylindrical shape. An element molding member is disclosed.

  Further, a plurality of intermediate molds are stacked in the major axis direction (vertical direction) of the element forming member, and the upper region of the region sandwiched between the intermediate molds, the uppermost intermediate mold, and the upper and lower pairs of molds are arranged. Materials for molding the elements in the area sandwiched between the mold (upper mold), the lowest intermediate mold, and the lower mold (lower mold) of the upper and lower pairs An element forming member that can form a plurality of elements at a time by disposing is disclosed.

JP-A-1-176240

  However, the inventor has found that the element forming member disclosed in Patent Document 1 described above has the following problems. That is, in the conventional element molding member described above, the axial direction (in the center of the transfer surface) of the surface (transfer surface) for transferring the shape of the element (lens) to be molded to the material, which exists on both surfaces of the intermediate mold The normal direction extending perpendicularly to the transfer surface) may be inclined with respect to the major axis direction of the entire element forming member (the major axis direction of the body mold). In particular, the intermediate mold has a transfer surface for transferring the shape of the element (lens) to be molded to the material on two surfaces (upper and lower surfaces) intersecting with the major axis direction of the barrel mold. It is difficult to control the inclination of the transfer surface in the axial direction with respect to the long axis direction of the body mold.

  When the intermediate mold is formed in a state in which the intermediate mold is inclined with respect to the major axis direction of the pair of upper and lower molds and the barrel mold, the intermediate mold has the intermediate mold transferred to the intermediate mold. The shape is different from the shape at the time of design due to the inclination of the element (the surface shape of the element is inclined with respect to the shape at the time of design according to the inclination of the intermediate mold). For this reason, the shape accuracy of the molded element deteriorates, and there is a possibility that problems such as a shape defect of the element occur.

  Therefore, in order to control the inclination described above, for example, by increasing the length (thickness) in the direction along the major axis direction (vertical direction) of the entire element forming member of the intermediate mold, It is conceivable to increase the contact area of the intermediate mold with the surface. In this way, it is considered that the intermediate mold is prevented from being inclined with respect to the major axis direction of the other components of the element forming member such as the trunk mold. However, in order to suppress the inclination of the intermediate mold with respect to the barrel mold by this method, it is necessary to make the thickness of the intermediate mold very large. As a result, it is conceivable that the size of the element molding member in the major axis direction is increased, and as a result, the cost of the entire equipment for the element molding member is increased. Also, when heating a pair of upper and lower molds during molding, it is difficult to uniformly heat the entire components such as molds because of the large equipment (so-called soaking problem occurs). There is.

  Further, if the forming process is performed while the inclination of the intermediate mold cannot be controlled, that is, the axial direction of the intermediate mold is inclined with respect to the major axis direction of the body mold, the following problems may occur. Conceivable. That is, when a pair of dies or intermediate dies are pressed for molding in a state where the transfer surface for transferring the shape of the element (lens) to be molded in the intermediate mold is inclined with respect to the long axis of the barrel mold. When the pressing is performed, the edge portion of the inclined transfer surface of the intermediate mold may interfere with the inner peripheral surface of the barrel mold to cause galling, and the inner peripheral surface of the barrel mold may be damaged. Further, the edge portion of the intermediate transfer surface inclined may be damaged. The occurrence of such damage deteriorates the durability of the components of the element forming member. Therefore, it is considered that it is necessary to perform the molding process while controlling the axial direction of the intermediate mold so as not to be inclined with respect to the major axis direction of the trunk mold.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide an element molding member that can suppress the occurrence of damage to components such as an intermediate mold and that can mold a plurality of elements at one time. The manufacturing method of the element using the said element shaping member, and the element formed using the said element shaping member are provided.

  The element forming member for forming an element according to the present invention includes a plurality of laminated elements arranged in a stacked manner. The laminated element is connected to a pair of molds for forming, a hollow body mold disposed so as to surround the outer peripheral surface of the mold, and one of the pair of molds, And a pressing member that presses along the inner peripheral surface of the trunk mold in the longitudinal direction of the trunk mold. And a lamination | stacking element is laminated | stacked along the longitudinal direction of a trunk | drum. The pressing member may have a flange portion that extends outward from the outer peripheral side surface of the body mold. In the laminated element laminated, the flange portion in one laminated element is an end face (crossing the outer peripheral side surface) of the body forming the other laminated element laminated on the side where the pressing member of the one laminated element is disposed. Contact surface).

  In this way, when a plurality of laminated elements are laminated, one of the pair of molds can be pressed from the major axis direction (along the inner circumferential surface of the trunk mold in the major axis direction of the trunk mold) by the pressing member. Therefore, it is possible to suppress the occurrence of the problem that the mold is inclined with respect to the trunk mold due to the stress applied to the mold (intermediate mold) through the material constituting the element as in the prior art.

  In addition, since a plurality of laminated elements including a pair of molds (upper mold and lower mold), a trunk mold, and a pressing member are stacked in a direction along the major axis direction (that is, the vertical direction), one time By the processing, the element can be formed by each of the laminated elements. That is, if the element molding member according to the present invention is used, a plurality of elements can be molded with high efficiency and high quality while suppressing the inclination of the mold by one treatment.

  Further, in the element molding member, the pressing member extends along the inner peripheral surface of the trunk mold in the major axis direction of the trunk mold, and an insertion portion that is inserted into a cavity portion defined by the inner peripheral surface of the trunk mold. It is preferable to include. More preferably, the pressing member includes a restraining portion that extends along the outer peripheral surface of the trunk mold in the major axis direction of the trunk mold and surrounds at least a part of the outer peripheral surface of the trunk mold. If it does in this way, the moving direction of a press member can be prescribed | regulated reliably to the direction along the long axis direction of the same type.

  The pressing member is connected to one of the pair of molds (for example, the upper mold) and includes an insertion portion that is inserted into a hollow portion formed by the inner periphery of the barrel die, so that the surface of the insertion portion is It becomes the restraint part (pressing member restraining part) with respect to the trunk | drum type | mold of a pressing member. Therefore, the pressing member restraining portion facing the inner peripheral surface of the trunk mold serves as a guide section for the pressing member to slide in the direction along the long axis direction of the trunk mold. Further, if the pressing member is inclined with respect to the major axis direction of the trunk mold, the pressing member restraining portion interferes with the inner periphery of the trunk mold. Therefore, the pressing member can be slid in the direction along the inner peripheral surface of the trunk mold while suppressing the inclination of the pressing member with respect to the direction along the major axis direction of the trunk mold by the pressing member restraining portion.

  In addition, the pressing member includes a restraining portion (pressing member restraining portion) that surrounds at least a part of the outer peripheral surface of the trunk mold, so that the pressing member is restrained from the outer peripheral surface side of the trunk mold as well as to the trunk mold. In this state, if the pressing member slides in the direction along the long axis direction of the trunk mold, the pressing member restraining portion that faces the outer peripheral surface of the trunk mold has the pressing member in the direction along the long axis direction of the trunk mold. It has a role as a guide part for sliding. Further, if the pressing member is inclined with respect to the longitudinal direction of the trunk mold, the pressing member restraining portion interferes with the trunk mold (the outer peripheral surface thereof). Therefore, the pressing member can be slid while suppressing the inclination of the pressing member with respect to the direction along the long axis direction of the trunk mold by the pressing member restraining portion. For this reason, since the inclination of the mold pressed by the pressing member can be suppressed, the edge portion of the mold interferes with the inner surface of the body mold, and galling occurs, or the inner surface of the body mold and the edge portion of the mold are damaged. Can be suppressed.

In the element forming member for forming an element according to the present invention, it is preferable that at least the planar outer shape of the trunk mold and the in-plane shape of the restraining portion of the pressing member are circular. Then, the restraining portion of the pressing member facing the outer peripheral surface of the trunk mold, that is, the pressing member restraining portion is set to L _o (mm), the length in the direction along the major axis direction of the portion overlapping the outer peripheral surface of the trunk mold. _Dsi (mm) is a circular inner diameter (diameter of the in-plane shape) formed by a cross section intersecting the major axis direction of the restraining portion (pressing member restraining portion) of the member, and a cross section intersecting the major axis direction of the trunk mold The outer diameter of the circle (the diameter of the planar outer shape) is D _o (mm), the thermal expansion coefficient of the body mold is α ₁ (/ ° C.), the thermal expansion coefficient of the pressing member is α ₂ (/ ° C.), and the material is If the difference between the temperature at which the material is heated during molding (that is, the heating temperature of the element molding member) and the room temperature at which the material is placed between a pair of molds is ΔT (° C.),
0.5 ° ≧ arctan ((D _si α ₂ −D _o α ₁ ) × ΔT / L _o )
It is preferable to satisfy the relationship. If the above-described mathematical formula is satisfied, the pressing member restraining portion (sleeve) of the pressing member connected to the upper die is heated even when the body mold and the pressing member are thermally expanded by heating the material when forming the material. The angle formed by the extending direction of the restraint portion with respect to the outer peripheral surface of the trunk mold can be maintained within a desired range (0.5 ° or less). For this reason, the degree to which the pressing member is inclined with respect to the major axis direction of the trunk mold can be reduced, and as a result, the mold inclination with respect to the major axis direction of the trunk mold can be reduced.

Similarly, in the element molding member for molding an element according to the present invention, the in-plane shape of the body mold and the planar outer shape of the mold are preferably circular. In addition, the inner diameter (in-plane shape diameter) of the circle formed by the cross section intersecting the major axis direction of the trunk mold is D _i (mm), and the circular diameter formed by the section intersecting the major axis direction of the mold ( D _p (mm) for the planar outer diameter), α ₁ (/ ° C.) for the thermal expansion coefficient of the body mold, α ₃ (/ ° C.) for the mold thermal expansion coefficient, and the temperature at which the material is heated when forming the material And if the difference from room temperature where the material is placed between a pair of molds is ΔT (° C),
α ₁ <α ₃ and
0.030 ≧ (α ₁ D _i −α ₃ D _p ) ΔT + (D _i −D _p ) ≧ 0.003
It is preferable to satisfy the relationship.

  By satisfying the above-described mathematical formula, when the element forming member is heated during the molding process, the pair of molds and the trunk mold are in a state where the pair of molds and the trunk mold are thermally expanded. While making a clearance smaller than the said clearance gap at room temperature, the said clearance gap in a heating state can be made into a predetermined | prescribed magnitude | size. For this reason, the two molds (the upper mold and the lower mold) forming a pair of molds are displaced from each other in the direction perpendicular to the major axis direction (radial direction) of the trunk mold inside the trunk mold. (Displacement amount) can be made extremely small. Further, even when heating is performed, the amount of the gap between the specific pair of molds and the trunk mold can be 0.003 mm or more and 0.030 mm or less (3 μm or more and 30 μm or less).

  Regarding the material constituting each component of the element forming member according to the present invention, first, the material of the pressing member is quartz glass, glassy carbon, graphite, silicon nitride, silicon carbide, alumina, boron carbide, zirconia, tantalum carbide, It is preferable to include any one selected from the group consisting of molybdenum and tungsten.

  In this case, when the element shaping member is heated together with the material to be the element in the element molding process, the portion of the pressing member that faces the surface of the body mold (inner surface or outer surface) with respect to the surface of the body mold Slidability can be maintained. Further, when the pressing member includes the above-described restraint portion, a material having a thermal expansion coefficient larger than that of the above-described material is used as the body mold material, so that a gap between the restraint portion and the body mold during heating is formed. It can be smaller than the gap at room temperature. As a result, the inclination of the pressing member with respect to the major axis direction of the trunk mold can be suppressed.

  In addition, by using a high-strength (high Young's modulus) material as the pressing member, elastic deformation of the European pressure member is reduced, and as a result, the pressing member is less likely to tilt with respect to the major axis direction of the trunk mold (with respect to the tilt). Resistance increases). As a result, the inclination of the pressing member with respect to the major axis direction of the trunk mold can be reduced. As a material satisfying the above conditions, a material including any one selected from the above group is preferably used as the material of the pressing member.

Next, with respect to the body mold, in order to satisfy the above-described formula, at least 90 mass of a material having a thermal expansion coefficient of 1.0 × 10 ⁻⁷ (/ ° C.) or more and 3.5 × 10 ⁻⁶ (/ ° C.) or less. %, For example, it is preferable to contain at least 90% by mass of quartz glass. In this case, the conditions shown by the above-described mathematical formula can be satisfied. In general, quartz glass is often used as the body material. In addition, examples of other materials having a coefficient of thermal expansion within the above-described range include glassy carbon and silicon nitride, and these materials may be used as the barrel material.

  Of the pair of outer peripheral surfaces of the mold, at least the sliding surface facing the inner peripheral surface of the body mold is preferably made of a material containing carbon. Here, the material containing carbon preferably includes any one selected from the group consisting of graphite, glassy carbon, DLC, and diamond.

  In general, the material of the pair of molds is preferably formed of a material containing carbon, including not only the sliding surface facing the inner peripheral surface of the body mold but also the entire mold. By using a material containing carbon as described above, the heat resistance of the mold can be improved. In particular, at least the sliding surface facing the inner peripheral surface of the trunk mold is made of a material containing carbon, whereby the slidability between the mold and the trunk mold can be improved. Here, examples of the carbon allotrope include graphite, glassy carbon, DLC, diamond, and the like, and the sliding surfaces facing at least the inner peripheral surface of the body type of the pair of molds described above are It may be formed of a material containing

  In the element forming member according to the present invention, an R chamfering process of 0.2 mm or more and 1.0 mm or less is performed at an edge portion where a sliding surface of a pair of upper and lower molds and a pressing surface pressing a material intersect. C chamfering is preferably performed. Here, the R chamfering process refers to a process of forming a curved shape (R surface part) having a radius (R) with a boundary between two surfaces, and the C chamfering process refers to two intersecting surfaces. A process of forming a surface (C surface portion) so as to intersect the two surfaces at a predetermined angle (usually 45 °) at the boundary portion. In the case of R chamfering, the radius (R) described above is preferably 0.2 mm or more and 1.0 mm or less, and in the case of C chamfering, in the direction perpendicular to the extending direction of the boundary between two intersecting surfaces. The width of the C-plane portion is preferably 0.2 mm or greater and 1.0 mm or less.

  By performing such R chamfering or C chamfering, it is possible to suppress galling or biting of the mold into the body mold. Further, since the chamfered portions such as the R surface portion and the C surface portion suppress the above-described galling and biting, the slidability between the die and the barrel die can be improved.

  In the element molding member according to the present invention, the laminated element may further include a frame mold for adjusting the position of the material constituting the element between the pair of molds. The frame mold is preferably made of a ceramic having a bending strength of 300 MPa or more. More specifically, the frame mold is preferably made of a material including any one selected from the group consisting of silicon carbide, silicon nitride, alumina, boron carbide, zirconia, and tantalum carbide.

  The frame mold is used to adjust the position of the material constituting the element between a pair of molds, and the pressure pressed during molding is directly applied to the frame mold as a side pressure. For this reason, the frame mold is preferably formed using a high-strength material (showing high bending strength). Therefore, the frame mold is preferably made of a material including any one selected from the material group as described above. In general, it is preferable to include a material having the strength described above.

  The element manufacturing method using the element forming member described above includes a step of preparing a material constituting the element and a step of disposing the material between a pair of molds in a plurality of laminated elements of the element shaping member. And a step of laminating and arranging a plurality of laminated elements, a step of heating the material, and a step of pressing the material. In the step of pressing the material, the material is pressed by applying stress to the assembly of the stacked elements along the stacking direction. If it does in this way, a plurality of elements can be shape | molded by one process, suppressing the inclination of a type | mold, using the element shaping | molding member as mentioned above. For this reason, an element can be shape | molded by the said process with high efficiency and high quality.

  The element which concerns on this invention is manufactured using the said member for element shaping | molding. From another point of view, the element according to the present invention is manufactured using the above-described element manufacturing method. In this case, an element having no shape defect such as an inclination can be efficiently manufactured without damaging the element shaping member, and an element with reduced manufacturing cost can be realized.

  According to the element molding member of the present invention, a plurality of elements can be molded with high efficiency and high quality while suppressing the inclination of the mold by a single treatment. In addition, an element formed using the element molding member of the present invention can be a high quality element with little axis inclination and eccentricity.

It is a schematic sectional drawing which shows the structure of the member for element shaping | molding in one situation based on embodiment of this invention. It is a schematic sectional drawing which shows the structure of the member for element shaping | molding in the other situation based on embodiment of this invention. It is a schematic sectional drawing which shows each component of 1 set (lamination | stacking element) of the element forming member of FIG. 2, and the dimension and thermal expansion coefficient of each component. FIG. 4 is an enlarged schematic view of a main part “IV” surrounded by a dotted line in FIG. 3. FIG. 3 is a simplified cross-sectional view showing each set of constituent elements of the element forming member of FIG. 2 and the dimensions and thermal expansion coefficients of the constituent elements. FIG. 6 is a simplified cross-sectional view showing only a coefficient of thermal expansion and dimensions before heating of a pair of molds and a trunk mold among the components in FIG. 5. FIG. 6 is a simplified cross-sectional view showing only a coefficient of thermal expansion and dimensions during heating of a pair of molds and a trunk mold among the components of FIG. 5. The state of the edge part where the outer peripheral surface of the upper mold intersects the pressing surface of the upper mold when the edge part of the region surrounded by the dotted line “VIII, IX” in FIG. FIG. The state of the edge part where the outer peripheral surface of the upper die and the pressing surface of the upper die intersect when the edge part of the region surrounded by the dotted line “VIII, IX” in FIG. FIG. It is a flowchart which shows the manufacturing method of the element using the member for element shaping | molding which concerns on this invention. It is a schematic sectional drawing which shows the shape | molded element.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each embodiment, portions having the same function are denoted by the same reference numerals, and the description thereof will not be repeated unless particularly necessary.

  As shown in FIG. 1, an element forming member 10 according to an embodiment of the present invention is an optical device used in various optical devices and optical communication devices such as a digital camera, a far-infrared camera, and a mobile phone. An element molding member for molding an element (as a lens). As shown in the cross-sectional view of FIG. 1, the element forming member 10 includes a plurality of laminated elements (three in FIG. 1) arranged in a stacked manner. The laminated element includes a pair of molds (upper mold 1 and lower mold 2) for forming, a hollow body mold 4 arranged so as to surround the outer peripheral surfaces of the upper mold 1 and the lower mold 2, and a pair of A pressing member 5 connected to the upper mold 1 which is one of the molds and pressing the upper mold 1 along the inner peripheral surface of the trunk mold 4 in the major axis direction of the trunk mold 4, and the upper mold 1 And a frame mold 6 for adjusting the position of the material 3 constituting the element between the lower mold 2 and the lower mold 2. The laminated elements are laminated along the long axis direction of the body mold 4. Further, the pressing member 5 has a flange portion extending outward from the outer peripheral side surface of the body mold 4. In the laminated element laminated, the flange portion in one laminated element is a body constituting another laminated element laminated on the side where the pressing member 5 of the one laminated element is disposed (upper side in FIG. 1). It is in contact with the end surface of the mold 4 (a surface intersecting the outer peripheral side surface, for example, the bottom surface of the body mold 4 in FIG. 1). The above-described trunk mold 4 is provided to house the upper mold 1 and the lower mold 2 and slide the upper mold 1 and the lower mold 2 inside the inner peripheral surface of the trunk mold 4. For example, the upper mold 1 and the lower mold are slid by sliding the upper mold 1 in the direction along the major axis direction (vertical direction in the figure) of the trunk mold 4 inside the inner peripheral surface (hollow portion) of the trunk mold 4. 2 can realize a state in which the material 3 is sandwiched (pressed state).

  Further, the pressing member 5 extends in a direction along the cylindrical inner peripheral surface formed by the trunk mold 4 in the longitudinal direction of the trunk mold 4 (that is, the vertical direction in FIG. 1), and the inner circumferential surface of the trunk mold 4. Includes an insertion portion to be inserted into the cavity portion defined by. More specifically, as shown in FIG. 1, the pressing member 5 has a width in the diameter direction (left-right direction in the figure) below (on the upper mold 1 side) above the pressing member 5 (on the body mold 4. It is narrower than the width in the diametrical direction of the portion where the flange portion in contact with the end face is formed. The area | region where the said width | variety narrowed in the press member 5 is an insertion part inserted in the cavity part which the inner peripheral surface of the trunk | drum 4 forms. As shown in FIG. 1, the insertion portion is a portion that faces the inner peripheral surface of the body mold 4 and restricts the moving direction of the pressing member 5 along the inner peripheral surface of the body mold 4. That is, the insertion portion is a restraining portion 5 a that restrains the movement of the pressing member 5 in the long axis direction of the trunk mold 4 in the direction along the inner circumferential surface by moving along the inner circumferential surface of the trunk mold 4. When the pressing member 5 slides in the direction along the long axis direction of the trunk mold 4 (up and down direction in the figure) due to the presence of the restraining portion 5a, the pressing member is pressed with respect to the long axis direction of the trunk mold 4. 5 can be prevented from tilting. Further, since the pressing member 5 is connected to the upper mold 1, the upper mold 1 is pressed by the pressing member 5 from the direction along the long axis direction of the trunk mold 4. Therefore, the upper mold 1 is pressed by the pressing member 5 from the direction inclined with respect to the major axis direction of the trunk mold 4, and as a result, the upper mold 1 can be prevented from tilting with respect to the major axis direction of the trunk mold 4. . That is, when the upper mold 1 slides in the vertical direction (the long axis direction of the trunk mold 4) on the hollow portion formed by the inner circumferential surface of the trunk mold 4, the upper mold 1 with respect to the major axis direction of the inner peripheral surface of the trunk mold 4 If the upper mold 1 is tilted, the end of the upper mold 1 and the inner peripheral surface of the body mold 4 come into contact with each other, and a galling phenomenon or a squeak phenomenon occurs. However, as described above, in the element molding member 10 according to the present invention, stress is not applied to the mold (intermediate mold) through the material constituting the element as in the conventional case, but the inclination included in the laminated element is Stress is applied to the upper mold 1 through the suppressed pressing member 5. For this reason, since it can suppress that the upper mold | type 1 inclines with respect to the major axis direction of the trunk | drum 4, it can suppress generation | occurrence | production of the above-mentioned galling phenomenon and a squeak phenomenon. As a result, it is possible to reduce the possibility of damage to the inner surface of the body die 4 and the end portion (edge portion) of the upper die 1, and to suppress the occurrence of eccentricity (shift, tilt) in the molded element. be able to.

  Also, among the pair of upper and lower molds, on the lower mold 2 on which the material 3 constituting the element to be molded is mounted on the upper surface, as shown in FIG. It is preferable to arrange a frame mold 6 (ring) for adjusting the position of the material 3 constituting the.

  Due to the presence of the frame 6, the material 3 can be disposed in the region surrounded by the frame 6 when the material 3 is disposed on the upper surface of the lower mold 2. Therefore, the material 3 can be set at an accurate position. Moreover, when the raw material 3 is heated, the sinterability of the side surface of the raw material 3 can be improved by efficiently propagating heat from the frame 6 to the side surface of the raw material 3.

  In FIG. 1 (the same applies to the following drawings), the material 3 may be in the form of a powder molded body before sintering by heating, or an element (element) after sintering by heating. 30: see FIG. 11).

  As shown in FIG. 1, an element molding member 10 according to an embodiment of the present invention includes a pair of molds (upper mold 1 and lower mold 2), a trunk mold 4, and a pressing member 5 described above. A plurality of laminated elements, each of which is a combination for forming the element, are laminated in a direction along the major axis direction (vertical direction in the drawing) of the body mold 4. In this way, the material 3 for molding the element is accurately positioned and disposed in each of the regions surrounded by the frame mold 6 disposed on the upper surface of the lower mold 2 stacked in a plurality. Can do. And if the raw material 3 is pressed and heated, each arranged raw material 3 will be shape | molded and an element will be formed. Therefore, a plurality of elements can be formed by a single process. Therefore, the element can be molded efficiently.

  The element forming member 10 shown in FIG. 2 basically has the same mode as the element forming member 10 shown in FIG. However, as shown in FIG. 2, the pressing member 5 of the element forming member 10 of FIG. 2 extends in a direction along the major axis direction of the outer peripheral surface of the trunk mold 4, and at least of the outer peripheral surface of the trunk mold 4. A sleeve 5b, which is a constraining portion surrounding a part, is included. Only in the above points, the element forming member 10 shown in the cross-sectional view of FIG. 2 is different from the element forming member 10 shown in the cross-sectional view of FIG.

  The sleeve 5b provided in the pressing member 5 of the element molding member 10 in FIG. 2 extends along the outer peripheral surface of the trunk mold 4 in the vertical direction of the figure, which is the major axis direction of the trunk mold 4. The extending part of the sleeve 5 b is arranged to face the outer peripheral surface of the body mold 4. The sleeve 5 b slides along the outer peripheral surface of the body mold 4. Therefore, since the sleeve 5b moves along the outer peripheral surface of the trunk mold 4, the movement of the sleeve 5b (that is, the pressing member 5) is surely restrained by the direction along the outer peripheral surface of the trunk mold 4. Therefore, when the sleeve 5b is present, the pressing member 5 and the upper die 1 are slid in the vertical direction of the figure along the longitudinal direction of the barrel die 4 so that the pressing member 5 and the upper die 1 become the barrel. Inclination with respect to the long axis direction of the mold 4 can be suppressed.

  In addition, the pressing member 5 of the element molding member 10 in FIG. 2 also has a restraining portion 5a facing the inner peripheral surface of the body mold 4 in the same manner as the pressing member 5 of the element molding member 10 in FIG. For this reason, the operation of the pressing member 5 in FIG. 2 is constrained by both the outer peripheral surface and the inner peripheral surface of the body mold 4. Therefore, the operation of the pressing member 5 in FIG. 2 is further restricted by the shape (inner peripheral surface and outer peripheral surface) of the body mold 4 than the pressing member 5 in FIG. Therefore, when the pressing member 5 slides in the vertical direction in FIG. 2, it is possible to further increase the effect of suppressing the pressing member 5 from being inclined with respect to the major axis direction of the trunk mold 4. Therefore, the effect of suppressing the inclination of the upper die 1 connected to the pressing member 5 with respect to the major axis direction of the trunk die 4 can be further increased. For this reason, when the upper mold 1 slides in the vertical direction on the hollow portion formed by the inner peripheral surface of the trunk mold 4, the upper mold 1 is inclined with respect to the major axis direction of the inner surface of the trunk mold 4. The possibility that a galling phenomenon or a squeak phenomenon will occur can be reduced. As a result, the possibility that the inner surface of the body mold 4 and the edge portion of the upper mold 1 are damaged by the above-described galling phenomenon or the like can be made smaller than that of the upper mold 1 in FIG. Occurrence of eccentricity (shift, tilt) can be further suppressed.

  Also, the element molding member 10 shown in FIG. 2 is a combination for molding one element including the pair of molds (upper mold 1 and lower mold 2), the trunk mold 4, and the pressing member 5 described above. A plurality of laminated elements are laminated in a direction along the long axis direction (vertical direction in the figure) of the body mold 4. In this way, a plurality of elements can be formed by a single process, similar to the element forming member 10 shown in FIG. 1 described above. Therefore, the element can be molded efficiently.

  As described above, the element molding member 10 shown in FIG. 1 is used for molding a lens as an optical element used in various optical devices and optical communication devices such as a digital camera, a far infrared camera, and a mobile phone. Therefore, when the main surface of the lens is circular, the material 3 constituting the element is arranged in a region inside the inner peripheral surface of the ring-shaped frame 6, but the outer surface of the element is shaped to be circular. In this case, at least one pair of molds in a planar outline, in-plane form of the barrel mold 4, a planar outline of the insertion portion of the pressing member 5 (restraint portion 5a in FIG. 1), and in-plane form of the frame mold 6 are circular. It is preferable to prepare so that it may become a shape. For other portions, the planar shape (the shape of the cross section intersecting the major axis direction (vertical direction in the figure)) is not necessarily a circular shape, and may be an arbitrary shape such as a quadrangle.

In FIG. 3, the pair of molds (upper mold 1 and lower mold 2), the trunk mold 4, and the pressing member 5 have a circular planar outer shape, and a sleeve that is a constraining portion of the outer circumferential surface of the trunk mold 4 to the pressing member 5. The length in the direction along the long axis direction of the portion surrounding the outer peripheral surface of the body mold 4 of 5b is L _o (mm), and the inside diameter of the circle formed by the cross section of the sleeve 5b intersecting the long axis direction is D _si (mm), D _o (mm), the outer diameter of the circle formed by the cross section intersecting the major axis direction of the body mold 4, α ₁ (/ ° C.) the thermal expansion coefficient of the body mold 4, and the heat of the pressing member 5 The expansion coefficient is α ₂ (/ ° C.).

Now, α ₁ <α ₂ , and before the element molding member 10 is heated for molding, the outer peripheral surface of the trunk mold 4 and the surface of the sleeve 5b facing the outer peripheral portion of the trunk mold 4 Assume that the distance between them was almost zero. At this time, the material 3 is disposed between a pair of molds for pressing the material 3 and a temperature at which the material 3 is heated to form the element (that is, a heating temperature of the element forming member 10). If the difference from room temperature is ΔT (° C.), the sleeve 5b in FIG. 4 is enlarged in FIG. 3 while the temperature of the pair of molds is increased from room temperature to the heating temperature by ΔT (° C.). Is expanded outward (right side in the figure) by D _si α ₂ ΔT (mm). Further, while the mold is heated by ΔT (° C.), the body mold 4 in FIG. 4 expands outward (right side in the figure) by D _o α ₁ ΔT (mm). Therefore, since the distance between the surface of the sleeve 5b facing the outer peripheral portion of the body mold 4 and the outer peripheral surface of the body mold 4 is almost zero before heating, as shown in FIG. The distance between the inner peripheral surface of 5b and the outer peripheral surface of the trunk mold 4 is
D _si α ₂ ΔT−D _o α ₁ ΔT = (D _si α ₂ −D _o α ₁ ) ΔT (mm)
It becomes. Therefore, as shown in FIG. 4, if the angle formed by the extending direction of the sleeve 5b with respect to the extending direction of the body mold 4 (vertical direction in the figure) is θ, approximately,
tan θ = (D _si α ₂ −D _o α ₁ ) × ΔT / L _o
It becomes. The angle θ shown in FIG. 4 is the inclination of the sleeve 5b with respect to the extending direction (long axis direction) of the body mold 4. In order to suppress the aforementioned galling phenomenon, squeak, and eccentricity (shift, tilt) in the element to be molded, θ is preferably 0.5 ° or less. Therefore,
0.5 ° ≧ arctan ((D _si α ₂ −D _o α ₁ ) × ΔT / L _o )
It is preferable to satisfy the relationship.

Even when α ₂ <α ₁ , 0.5 ° ≧ arctan ((D _si α ₂ −D _o α ₁ ) × ΔT / L _o ) as described above.
It is preferable to satisfy the relationship. In this case, therefore, the state before the heating element forming member 10 for forming, D _si is considerably greater than D _o, i.e. the outer circumferential surface of barrel die 4, and the outer peripheral portion of the barrel die 4 in the sleeve 5b It is preferable to have a considerable gap between the opposing surfaces.

5 to 7 are simplified diagrams showing dimensions and thermal expansion coefficients between the components as described above. For this reason, the shape of each component shown in FIGS. 5 to 7 is simplified from the actual one. 5 and 6, the pair of molds (upper mold 1 and lower mold 2), the body mold 4 and the pressing member 5 have a circular planar outer shape, and the element molding according to the present invention shown in FIG. among member 10, intersects the diameter of the circular inner forming cross section intersecting the axial direction of the barrel die 4 in the axial direction of the D _{i (mm),} 1 pair of mold (upper mold 1 and lower mold 2) The outer diameter of the circle formed by the cross section is D _p (mm), the thermal expansion coefficient of the body mold 4 is α ₁ (/ ° C.), and the thermal expansion coefficient of the pair of molds is α ₃ (/ ° C.).

In this case, in a state before the element molding member 10 is heated for molding, the difference in diameter between the outer peripheral surface of the pair of molds (upper mold 1 and lower mold 2) and the inner peripheral surface of the body mold 4 is as follows. a D _i -D _p (mm). At this time, the temperature at which the material 3 is heated to form the element (that is, the heating temperature of the element forming member 10), and the room temperature at which the material 3 is disposed when the material 3 is pressed, Is the difference ΔT (° C.). In this case, as shown in FIG. 7, the inner diameter of the circular shape formed by the cross section intersecting the major axis direction of the body die 4 after heating the die by ΔT (° C.) is D _i + α ₁ D _i ΔT (mm ), And the outer diameter of the circle formed by the cross section intersecting the major axis direction of the pair of molds (the upper mold 1 and the lower mold 2) is D _p + α ₃ D _p ΔT (mm) as shown in FIG. )

Here, when the mold is heated by ΔT (° C.), if the gap between the outer peripheral surface of the pair of molds and the inner peripheral surface of the body mold 4 is reduced, the upper mold 1 constituting the pair of molds 1 And the range of the position where the lower mold | type 2 is arrange | positioned becomes narrower. Therefore, it is possible to reduce the displacement of the position of the long axis between the upper mold 1 and the lower mold 2. For this purpose, α ₁ <α ₃ is preferable. If α ₁ <α ₃ , during heating, the gap between the pair of molds and the body mold 4 becomes smaller as the temperature rises due to thermal expansion.

More specifically, the amount of the gap described above (here, the outer peripheral surface formed by the cross section intersecting the major axis direction of the pair of molds with the diameter of the inner peripheral surface formed by the cross section intersecting the major axis direction of the body mold 4). The difference between the diameter and the diameter is referred to as the amount of gap) is preferably 0.003 mm or more and 0.030 mm or less (3 μm or more and 30 μm or less). That is,
0.030 ≧ (α ₁ D _i −α ₃ D _p ) ΔT + (D _i −D _p ) ≧ 0.003
It is preferable that The amount of the gap described above is more preferably 0.003 mm or more and 0.010 mm or less (3 μm or more and 10 μm or less). For example, if the amount of the gap is 3 μm or less, the amount of the gap is too small, so that the outer peripheral surfaces (sliding surfaces) of the upper mold 1 and the lower mold 2 interfere with the inner peripheral surface of the body mold 4, and a galling phenomenon occurs. There is a possibility that the outer peripheral surface of the upper mold 1 and the lower mold 2 and the inner peripheral surface of the body mold 4 may be damaged due to the occurrence of a crisp phenomenon. Further, by leaving at least about 3 μm of the gap, a so-called shrink-fitted state (when the element forming member 10 is heated, due to the influence of processing error and temperature unevenness at the time of forming, Occurrence of a state in which the inner diameter of the circular shape formed by the cross section of the body mold 4 is smaller than the outer diameter of the circular shape formed by the cross section of the pair of molds can be avoided.

  Conversely, if the amount of the gap exceeds 30 μm, the range of positions where the upper mold 1 and the lower mold 2 constituting a pair of molds can be arranged is widened, resulting in a large misalignment between the long axes of the two molds. When the molding process is performed, there is a possibility that the upper mold 1 or the lower mold 2 may be inclined with respect to the major axis direction of the body mold 4 or the element to be molded may be eccentric. From the above, the amount of the gap is preferably 0.003 mm or more and 0.030 mm or less.

The thermal expansion coefficient of the press member 5 alpha _{2 (/} ° C.) and about the relationship between the thermal expansion coefficient alpha ₁ of barrel die 4 _(/ ° C.), for example, the sleeve 5b to the pressing member 5 as shown in FIG. 2 Is preferably α ₂ <α ₁ . In this way, when the mold is heated by ΔT (° C.), the gap between the surface of the pressing member 5 facing the body mold 4 and the outer peripheral surface of the body mold 4 can be reduced. . For this reason, the range of the position where the upper mold | type 1 and the lower mold | type 2 which comprise a pair of type | mold are arrange | positioned becomes narrower. Therefore, it is possible to minimize the displacement of the position of the major axis between the upper mold 1 and the lower mold 2. That is, if α ₂ <α ₁ , the gap between the sleeve 5b of the pressing member 5 and the outer peripheral surface of the body mold 4 during heating can be reduced.

Further, for example, as shown in FIG. 1, when the sleeve 5 b is not present in the pressing member 5, if α ₁ <α ₂ , when the mold is heated by ΔT (° C.), the body shape of the pressing member 5 4, the gap between the surface facing the inner peripheral surface of the body mold 4 and the inner peripheral surface of the body mold 4 can be reduced. In addition, regarding the pressing member 5 in which the sleeve 5b shown in FIG. 2 is present, by setting α ₁ <α ₂ , the surface of the sleeve 5b of the pressing member 5 that faces the body mold 4 and the outer peripheral surface of the body mold 4 The gap becomes large, and this may cause a tilt of the pressing member 5 with respect to the body mold 4. However, for example, by increasing the length L _o (see FIGS. 3 and 4) of the long axis direction of the sleeve 5 b shown in FIG. 2, the degree to which the sleeve 5 b is restrained with respect to the outer peripheral surface of the body mold 4 is increased. be able to. As a result, the occurrence of the inclination of the pressing member 5 with respect to the major axis direction of the outer peripheral surface of the trunk mold 4 can be suppressed.

From the above, it is preferable to select the material of the pressing member 5 so that α ₂ <α ₁ when the sleeve 5b is present as shown in FIG. 2, for example, as shown in FIG. In this case, it is preferable to select the material so that α ₁ <α ₂ . Note that, in the pressing member 5 to the sleeve 5b is present, if you select the material so that α _{1 <α 2,} it is preferable to increase the L _o.

  In particular, as the pressing member 5, it is preferable to use a material having high strength (high Young's modulus). In this way, even if the major axis direction of the pressing member 5 is likely to be inclined with respect to the major axis direction of the trunk mold 4 due to the influence of the arrangement or external force, the pressing member 5 is elastically deformed. There is little and resistance to inclination becomes strong. As a result, the inclination of the pressing member 5 with respect to the major axis direction of the trunk mold 4 can be reduced.

  For the above reasons, the pressing member 5 is any one selected from the group consisting of quartz glass, glassy carbon, graphite, silicon nitride, silicon carbide, alumina, boron carbide, zirconia, tantalum carbide, molybdenum, and tungsten. It is preferable to use a material containing.

Next, specific materials for forming each component other than the pressing member 5 of the element forming member 10 will be described. First, the body mold 4 is formed using a material containing at least 90% by mass or more of a material having a thermal expansion coefficient of 1.0 × 10 ⁻⁷ (/ ° C.) to 3.5 × 10 ⁻⁶ (/ ° C.). Is preferred. In particular, it is preferable to use a material containing at least 90% by mass or more of quartz glass having a thermal expansion coefficient of 5.0 × 10 ⁻⁷ (/ ° C.). Moreover, it is more preferable to use the material made of the above-described quartz glass (including 100% by mass of quartz glass) as the material of the body mold 4.

  As described above, the use of quartz glass as the body mold 4 increases the degree of freedom in selecting materials for the upper mold 1 and the lower mold 2. Further, since the thermal expansion coefficient of quartz glass is small, for example, when performing the process of placing the material in a mold at room temperature, the gaps between the upper mold 1 and the lower mold 2 and the body mold 4 are increased, and the process is performed. There is an effect that it can be easily performed. Furthermore, quartz glass has an advantage of high thermal conductivity of radiant heat. In addition, the influence of each effect and advantage mentioned above appears notably by including 90 mass% or more of quartz glass in the trunk die 4.

  For example, silicon nitride may be used as the body mold 4 instead of quartz glass. Here, in order to achieve the effect that the above-described processing can be easily performed, for example, the gaps between the upper mold 1 and the lower mold 2 and the body mold 4 are increased as in the case of using the quartz glass described above. More preferably, the body die 4 containing at least 90% by mass or more of silicon nitride is used.

  The pair of molds composed of the upper mold 1 and the lower mold 2 is preferably formed of a material containing carbon. Here, the material containing carbon preferably includes any one selected from the group consisting of graphite, glassy carbon, DLC, and diamond.

As a material of a pair of molds, not only a sliding surface that is an outer peripheral surface extending in the major axis direction of the upper mold 1 and the lower mold 2 but generally the entire mold contains carbon as described above. It is preferable that it is made of a material. In this way, the entire mold can be integrally formed with the material, compared to the case where only the sliding surface is made of a material containing carbon, so that the manufacturing process of the mold can be simplified. For example, the thermal expansion coefficient of glassy carbon is 2.8 × 10 ⁻⁶ (/ ° C.), and the thermal expansion coefficient of diamond is 1.1 × 10 ⁻⁶ (/ ° C.). It becomes easy for the expansion coefficient to satisfy the above-described condition of α ₁ <α ₃ .

  However, the sliding property between the pair of molds and the body mold 4 is improved by forming at least the sliding surface opposed to the inner peripheral surface of the body mold 4 with a material containing carbon preferentially. Can do. Here, examples of the carbon allotrope include graphite, glassy carbon, DLC, and diamond. The sliding surfaces facing at least the inner peripheral surface of the body mold 4 of the pair of molds described above are If it is formed with the material containing, sufficient slidability with respect to the trunk | drum 4 can be ensured.

  In the step of pressing the material at the time of molding, a large pressure (side pressure) is applied to the frame mold 6 that is a ring when the surface of the upper mold 1 facing the lower mold 2 contacts the frame mold 6. For this reason, it is preferable to use a material having a high bending strength for the frame mold 6 assuming that a strength, particularly a stress larger than the side is applied. Specifically, it is preferably formed of ceramics having a bending strength of 300 MPa or more, and more preferably contains at least 90% by mass of ceramics. If the frame 6 is formed using such a material, high durability can be maintained even when a large pressure is applied during molding (pressing).

  Specifically, the frame mold 6 is preferably made of a material including any one selected from the group consisting of silicon carbide, silicon nitride, alumina, boron carbide, zirconia, and tantalum carbide.

  In particular, in order to further improve the slidability between the upper mold 1 and the lower mold 2 and the trunk mold 4, as shown in FIGS. 8 and 9, for example, the inner peripheral surface of the trunk mold 4 of the upper mold 1 An edge surface where the upper mold outer peripheral surface 1c, which is an opposing sliding surface, and the pressing surface that presses the material 3 intersect each other has an R surface 7 (R chamfering process) of 0.2 mm or more and 1.0 mm or less. It is more preferable to provide a portion) or a C surface 8 (a portion subjected to C chamfering). If the edge portion is a sharp corner portion where the R surface 7 and the C surface 8 are not processed, when the upper die 1 slides in the direction along the major axis direction, the edge portion of the upper die 1 As a result of interfering with the inner peripheral surface of the trunk mold 4 or foreign matters entering between the edge portion and the inner peripheral surface of the trunk mold 4, there is a possibility of inducing a phenomenon called galling or scratching. In order to suppress this phenomenon, it is preferable to have a structure provided with an R surface 7 and a C surface 8.

  In this way, even if the upper mold outer peripheral surface 1c comes into contact with the inner peripheral surface of the barrel mold 4, the edge portion is displaced from the inner peripheral surface of the barrel mold 4, so that the edge portion is It is possible to reduce the possibility of galling and scumming due to interference with the inner peripheral surface of the mold 4.

  8, the radius A of the R surface 7 of the edge portion is preferably 0.2 mm or more, and the dimension B of the C-cut portion of the edge portion in FIG. 9 is preferably 0.2 mm or more. However, if the R surface 7 and the C surface 8 become too large, the upper mold 1 and the lower mold 2 may be inclined with respect to the trunk mold 4. For this reason, the radius A of the R surface 7 is preferably 1.0 mm or less, and the dimension B of the C surface 8 is preferably 1.0 mm or less.

  As described above, the element forming member 10 according to the embodiment of the present invention is, for example, the upper mold 1 with respect to the major axis direction of the inner surface of the body mold 4 when the pair of molds slides in the vertical direction. By tilting, it is highly efficient to process multiple elements in a single process while reducing the possibility of galling and squeezing and damaging the inner surface of the body mold 4 and the edge of the upper mold 1. Can be molded.

  Next, a method for manufacturing an element using the element forming member 10 in the embodiment of the present invention described above will be described with reference to FIG.

  As shown in FIG. 10, first, a material preparing step (S10) is performed. In this step (S10), specifically, for example, ZnS (zinc sulfide) powder is prepared as the material 3 for molding the element.

  Next, a step (S20) of placing the material on the mold is performed. In this step (S20), specifically, in the lower mold 2 on the inner peripheral side region of the frame mold 6 having an annular shape disposed on the upper surface which is the surface facing the upper mold 1, The material 3 described above is arranged. Then, as shown in FIG. 1 or FIG. 2, the upper mold 1 is set on the lower mold 2 and arranged so that a pair of upper and lower molds mesh with each other. Further, the pressing member 5 is disposed on the upper mold 1. Then, the lower mold 2, the upper mold 1, the frame mold 6, and the pressing member 5 on which the material 3 is disposed are arranged inside the trunk mold 4 to prepare a laminated element. Then, a plurality of the laminated elements are laminated as shown in FIG. 1 and FIG.

  Next, a step of heating the mold (S30) is performed. Specifically, the entire element forming member 10 including the material 3 arranged in the pair of molds in the previous step (S20) is heated to 980 ° C.

  Next, a step of pressing the material (S40) is performed. Specifically, pressure is applied from the upper mold 1 side to the lower mold 2 side by applying stress from above to the pressing member 5 in the uppermost laminated element using a pressure member (not shown in FIG. 2). In this way, pressure is applied to the material 3 heated in the previous step (S30). Then, the material 3 can be molded. The pressure application in the step (S40) may be gradually started while performing the previous step (S30). After the molding is completed, the element 30 (see FIG. 11) is taken out from the element molding member 10. Thus, the element 30 can be manufactured using the element forming member 10 according to the present invention.

  In order to confirm the effect of the present invention, the following tests were conducted. Specifically, by using an element molding member that has been molded using the element molding member 10 according to the above-described embodiment of the present invention and a conventionally used element molding member disclosed in Patent Document 1 described above. A test was conducted to evaluate the inclination with the molded element.

(Sample preparation)
The above-described element forming member 10 in which the sleeve 5b does not exist in the pressing member 5 shown in FIG. 1, the element forming member 10 in which the sleeve 5b exists in the pressing member 5 shown in FIG. 1, an element as a sample was molded using the element molding member (optical element molding die) disclosed in FIG. In addition, Table 1 is a table | surface which shows the material used for each component of the member for various element formation used in Example 1. FIG. As shown in Table 1, all of the element molding members used in Example 1 were formed of a pair of molds, that is, the upper mold 1 and the lower mold 2 made of glassy carbon. The body mold 4 was made of quartz glass, and the pressing member 5 and the frame mold 6 were made of silicon nitride.

  As sample types, as shown in Tables 2 and 3, six types of samples ID1A to 1F were prepared. These samples of ID1A to 1F were manufactured using element forming members having different conditions as shown in Table 2 and Table 3, respectively.

  Table 2 shows the conditions of the element-forming member (see FIG. 1) used for the manufacture of the sample without the sleeve 5b and the results of the inclination evaluation for the manufactured sample. Table 3 shows the conditions of the element forming member (see FIG. 2) in which the sleeve 5b is used, which was used for the manufacture of the sample, and the results of the tilt evaluation for the manufactured sample.

  As shown in Tables 2 and 3, for the samples ID1A to 1F, the structure of the element molding member 10 used for manufacturing and the dimensions of each component (upper mold 1, lower mold 2, barrel mold 4, etc.) Is different. Specifically, as shown in Table 2, the outer diameter Dp (mm) of the upper mold 1 and the lower mold 2 of the element molding member 10 in ID1A (see FIG. 5: the upper mold 1 and the lower mold 2 of the trunk mold) The outer diameter of the circle formed by the cross-section intersecting with the major axis direction 4 was 30.000 mm. In addition, the inner diameter Di (mm) of the body mold 4 of the element forming member 10 (see FIG. 5: a circular inner diameter formed by a cross section intersecting the major axis direction of the body mold 4) was set to 30.020 mm. Further, as shown in Table 2, the outer diameter Dp (mm) of the upper die 1 and the lower die 2 of the element forming member in ID1F as a comparative example was set to 30.000 mm. Further, the inner diameter Di (mm) of the body mold 4 of the element molding member was set to 30.020 mm.

Further, as shown in Table 3, IDs 1B to 1E are data when the element forming member 10 shown in FIG. 2 according to the embodiment of the present invention is formed using each material shown in Table 1. . As shown in Table 3, the element forming members 10 in IDs 1B to 1E are different only in dimensions. Specifically, with respect to the outer diameter D _o (mm) of the body mold 4 (see FIG. 3: a circular outer diameter formed by a cross section of the body mold 4 intersecting the major axis direction), the element forming member 10 of ID1B. Is 30.000 mm, ID1C element molding member 10 is 20.000 mm, ID1D element molding member 10 is 15.000 mm, and ID1E element molding member 10 is 30.000 mm. In addition, regarding the inner diameter D _si (mm) of the sleeve 5b (see FIG. 3: the circular inner diameter formed by the cross section of the sleeve 5b intersecting the major axis direction), the ID1B element forming member 10 is 30.050 mm or less, The ID1C element molding member 10 was 20.020 mm, the ID1D element molding member 10 was 15.020 mm, and the ID1E element molding member 10 was 30.030 mm. Regarding the length (mm) of the sleeve 5b (see FIG. 3: the length in the direction along the major axis direction of the portion where the sleeve 5b surrounds the outer peripheral surface of the body mold 4), ID1B is 10 mm, ID1C is 20 mm, ID1D Was 15 mm and ID1E was 5 mm. These are all dimension values at room temperature.

  Samples (elements) of ID1A to 1F were molded by 100 using each element molding member 10. In each element forming member, the elements were molded in a state where the elements were stacked so that three elements could be formed at a time.

  Hereinafter, a method for manufacturing the sample will be specifically described. As shown in FIG. 10, first, a material preparing step (S10) is performed. Specifically, in Example 1, ZnS (zinc sulfide) powder was prepared as the material 3 for molding the element.

  And as shown in FIG. 10, the process (S20) of arrange | positioning a raw material to a type | mold is implemented. Specifically, in the first embodiment, the above-described material is disposed in the region on the inner peripheral side of the frame die 6 having an annular shape, which is disposed on the upper surface of the lower die 2 that is the surface facing the upper die 1. 3 was placed. Then, as shown in FIG. 1 or FIG. 2, the upper mold 1 was set on the lower mold 2 and arranged so that a pair of upper and lower molds meshed with each other. Further, the pressing member 5 is disposed on the upper mold 1. And the lamination | stacking element was prepared by arrange | positioning the lower mold | type 2, the upper mold | type 1, the frame type | mold 6, and the press member 5 in which the raw material 3 was arrange | positioned inside the trunk | drum 4. A plurality (four in this case) of the laminated elements were laminated as shown in FIG. 1 and FIG.

  Subsequently, as shown in FIG. 10, a step of heating the mold (S30) is performed. In Example 1, the element forming member including the material 3 arranged in the previous step (S20) was specifically heated to 980 ° C.

And as shown in FIG. 10, the process (S40) of pressing a raw material is implemented. Specifically, in the first embodiment, by using a pressing member of an apparatus not shown in FIG. 2, stress is applied from above to the pressing member 5 in the uppermost layered element, so that the lower mold 2 from the upper mold 1 side. A pressure of 50 MPa was applied to the side. Thus, a pressure of 50 MPa was applied to the material 3 (ZnS) disposed on the upper surface of the lower mold 2 in the previous step (S20).
The material 3 was formed by sintering the material 3 by the above procedure. As a result, an element 30 as shown in FIG. 11 was obtained.

  Referring to FIG. 11, the obtained element 30 includes a lens part located at the center part and an edge part arranged so as to surround the lens part. In order to evaluate the inclination of the element 30, the flatness of the edge surface 3c, which is the main surface of the edge, was measured as described later.

(contents of the test)
The inclination of the lens as the molded element 30 shown in FIG. 11 was measured. A three-dimensional measuring device (NH-3SP) manufactured by Mitaka Kogyo was used for the measurement. Specifically, the element 30 (lens) formed on a jig whose flatness is guaranteed to be 3 μm or less was fixed. Then, regarding 12 different points determined at substantially equal intervals in the direction along the circumference of the main surface of the element 30 on the edge surface 3c, which is a surface along the main surface, in the vicinity of the outer edge of the main surface of the element 30. The flatness of the edge surface 3c was calculated by measuring the coordinates. The angle calculated from the flatness of each surface of the edge surface 3 c with respect to the surface of the jig was evaluated as the inclination angle of the element 30.

(result)
The evaluation results are shown in the column “Tilt Evaluation” in Tables 2 and 3. In addition, in the column of “inclination evaluation”, when at least one of the measured inclination angles of 100 elements 30 exceeding 0.5 ° exists, the “inclination evaluation” is set to “x”. Further, when the measured inclination angle of all 100 pieces was 0.5 ° or less, the “inclination evaluation” was set to “◯”. Further, among them, in particular, when the measured inclination angle of all 100 pieces is 0.2 ° or less, “◎” is displayed. Further, among them, in particular, when the measured inclination angle of all 100 pieces is 0.05 ° or less, “☆” is displayed.

  As shown in Table 2, the evaluation of the inclination of the element 30 formed using the element forming member 10 shown in FIG. 1 according to the embodiment of the present invention is ID1A, that is, ID1F, For the element 30 formed by using a conventionally used element molding member, the inclination evaluation was x. From this, the element forming member 10 shown in FIG. 1 according to the embodiment of the present invention has the restraining portion 5a of the pressing member 5, the pressing member 5 and a pair of molds (upper mold 1 and lower mold 2). Since the tilting with respect to the major axis direction of the trunk mold 4 is suppressed, the tilt angle of the element 30 formed using the element molding member 10 of FIG. 1 is reduced. On the other hand, the element molding member of FIG. 4 of Patent Document 1 does not have a sleeve for suppressing inclination. For this reason, for example, there is a possibility that the intermediate die is molded while being inclined with respect to the long axis direction of the barrel die. Therefore, it can be said that there is a high possibility that the tilt angle of the element 30 to be formed becomes large.

  Moreover, as shown in Table 3, ID1B-1E is what formed the element 30 using the element shaping | molding member 10 shown in FIG. 2 which concerns on embodiment of this invention. “Evaluation” was “◯”, and “Inclination evaluation” was “◎” in ID1C and 1D, whereas “Inclination evaluation” was “x” in ID1E.

Here, in the element forming member 10 having the structure according to FIG. 2 described above in ID1B to 1D, each dimension shown in Table 3 has the formula 0.5 ° ≧ arctan ((D _si α ₂ −D _{o described above).} α ₁ ) × ΔT / L _o )
Meet. However, although the element forming member 10 in ID1E has the structure of FIG. 2 according to the embodiment of the present invention described above, each dimension shown in Table 3 does not satisfy the above-described mathematical formula. For this reason, especially in the element forming member 10 having the pressing member 5 including the sleeve 5b, it can be said that the effect of suppressing the inclination is increased by satisfying the above-described mathematical expression.

Incidentally, the element molding member 10 in ID1E in Table 3, in comparison with the element molding member 10 at each of the other ID, the value of _{L o} is smaller than the value of _{D o} and _{D si.} That is, the length of the sleeve 5b in the long axis direction of the trunk mold 4 is short. Since _Lo is short, even if the sleeve 5b tilts, the movement of the sleeve 5b is constrained by the outer peripheral surface of the body mold 4, and the probability of correcting the tilt is low. Further, when _Lo is small, the value of θ representing the inclination angle of the pressing member 5 in FIG.

Therefore, the value of L _o can be said that it is preferable to as large as possible. Especially element molding member 10 in ID1B and ID1C in Table 3, the value of _{L o} is greater than the value of _{D o} and _{D si.} That is, the length of the sleeve 5b in the long axis direction of the trunk mold 4 is long. Since _Lo is long, even if the sleeve 5b is tilted, the movement of the pressing member 5 is restrained by the outer peripheral surface of the trunk mold 4, and the probability of correcting the tilt of the pressing member 5 is increased. Further, when _Lo is large, the value of θ representing the inclination angle of the pressing member 5 in FIG.

  In Example 2, a test for confirming the degree of inclination when the material and dimensions of each component of the element forming member 10 having the structure shown in FIG. 2 according to the embodiment of the present invention are variously changed. I did it.

(Sample preparation)
Regarding the element forming member having the structure shown in FIG. 2, members of various materials and dimensions were prepared. Specifically, as shown in Table 4, ten types of element forming members ID2A to 2J were prepared. All samples of ID2A to 2J shown in Table 4 are elements manufactured using the element forming member 10 having the structure shown in FIG. 2 described above, that is, the element forming member 10 including the sleeve 5b. In the element forming member, the material and dimensions of each component (upper die 1, lower die 2, barrel die 4 and the like) are variously changed. 100 samples of each ID (2A to 2J) shown in Table 4 were formed using the prepared element forming member 10 in the same manner as in Example 1 described above. The sample (element) manufacturing method is basically the same as the sample manufacturing method in Example 1.

(contents of the test)
Using the same method as in Example 1, the inclination of the element was evaluated.

(result)
The evaluation result of the inclination is shown in the column of “Inclination evaluation” in Table 4. That is, as shown in Table 4, in all of the elements 30 formed using the ten types of element forming members 10 from ID2A to 2J, the “inclination evaluation” is any one of “◯”, “◎”, and “☆”. ing. In other words, the inclination angle was 0.5 ° or less in all (all 900) of the elements 30 formed by 100 with each of the ten element forming members 10. Therefore, it can be said that the conditions of the material and dimensions of each component of the ten types of element forming members 10 from ID2A to 2J are preferable conditions.

  Specifically, as shown in Table 4, for example, glassy carbon, DLC-coated SiC, DLC-coated carbide (tungsten carbide), and graphite can be used as the material of the upper mold 1 and the lower mold 2. Of the upper mold 1 and the lower mold 2, in particular, the outer peripheral surface (sliding surface) that slides while facing the inner peripheral surface of the body mold 4 is coated with, for example, DLC as described above, and at least the upper mold 1 and It is preferable to preferentially coat the sliding surface of the lower mold 2 with DLC. Here, the thickness for coating the DLC thin film is 3 μm, but the thickness of the thin film formed as the sliding surface is preferably 1 μm or more and 5 μm or less. Thus, if the sliding surfaces of the upper mold 1 and the lower mold 2 are preferentially configured by DLC, the sliding resistance can be further reduced.

Moreover, as a material of the trunk mold 4, as shown in Table 4, as a material having a thermal expansion coefficient of 1.0 × 10 ⁻⁷ (/ ° C.) or more and 3.5 × 10 ⁻⁶ (/ ° C.) or less, for example, Quartz glass, glassy carbon, silicon nitride, or the like can be used. The pressing member 5 is preferably made of a material having high strength (high Young's modulus) as described above. As shown in Table 4, quartz glass, glassy carbon, silicon nitride, silicon carbide, alumina, zirconia, Graphite, tungsten, molybdenum, or the like can be used.

As the material of the frame mold 6, it is preferable to use a material having high strength (high bending strength). As shown in Table 4, silicon nitride, silicon carbide, boron carbide (B ₄ C), alumina, zirconia, tantalum carbide. Etc. can be used.

The element forming member 10 in which the respective constituent elements are formed so as to have the dimension values shown in Table 4 using the respective materials described above is the above-mentioned for any of the items ID2A to 2J shown in Table 4. Formula 0.5 ° ≧ arctan ((D _si α ₂ −D _o α ₁ ) × ΔT / L _o )
Will be satisfied. Therefore, 100 elements were formed for the element forming member 10 in any item, and a high quality element in which no element 30 having an inclination angle exceeding 0.5 ° was generated could be formed. Further, as shown in FIGS. 1 and 2, the element forming member 10 according to the embodiment of the present invention can form a plurality of elements in one process, so that the element 30 can be formed with high efficiency. Could be formed.

  It should be considered that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  The present invention is particularly excellent as a technique for forming a high-quality element with suppressed inclination with high efficiency.

  DESCRIPTION OF SYMBOLS 1 Upper mold | type, 1c Upper mold | type outer peripheral surface, 2 Lower mold | type, 3 Material, 3c Edge surface, 4 Body type | mold, 5 Pressing member, 5a Restraint part, 5b Sleeve, 6 Frame type | mold, 7 R surface, 8 C surface, 10 element Molding member, 30 elements.

Claims (16)

An element forming member for forming an element;
A plurality of laminated elements arranged in a stack
The laminated element is
A pair of molds for molding;
A hollow body mold disposed so as to surround the outer peripheral surface of the mold;
A pressing member connected to one of the pair of molds, and pressing the one mold along the inner peripheral surface of the barrel mold in the longitudinal direction of the barrel mold;
The element for forming an element, wherein the laminated element is laminated along a long axis direction of the body mold.   2. The pressing member includes an insertion portion that extends along an inner peripheral surface of the barrel mold in a major axis direction of the barrel mold and is inserted into a hollow portion defined by the inner peripheral surface of the barrel mold. The member for element shaping | molding of description.   3. The pressing member according to claim 1, wherein the pressing member includes a restraining portion that extends along an outer circumferential surface of the barrel mold in a major axis direction of the barrel mold and surrounds at least a part of the outer circumferential surface of the barrel mold. Element molding member. The planar outer shape of the trunk mold and the in-plane shape of the restraining portion of the pressing member are each circular,
Of the restraining portions of the pressing member, the length in the direction along the major axis direction of the portion overlapping the outer peripheral surface of the barrel mold is L _o (mm), and the length of the restraining portion of the pressing member is the length. The inside diameter of the circle formed by the cross section intersecting the axial direction is D _si (mm), the outside diameter of the circle formed by the cross section intersecting the long axis direction is _Do (mm), and the body mold Α ₁ (/ ° C.), the thermal expansion coefficient of the pressing member is α ₂ (/ ° C.), the temperature at which the material is heated when forming the material, and the material as the pair of molds. If the difference from the room temperature placed between is ΔT (° C.),
0.5 ° ≧ arctan ((D _si α ₂ −D _o α ₁ ) × ΔT / L _o )
The element forming member according to claim 3, satisfying the relationship: The in-plane shape of the trunk mold and the planar outer shape of the mold are each circular.
D _i (mm) is an inner diameter of a circle formed by a cross section intersecting the major axis direction of the body mold, and D _p (mm) is a circular diameter formed by a section intersecting the major axis direction of the mold. The thermal expansion coefficient of the body mold is α ₁ (/ ° C.), the thermal expansion coefficient of the mold is α ₃ (/ ° C.), the temperature at which the material is heated when the material is molded, and the material is If the difference from room temperature placed between the pair of molds is ΔT (° C.),
α ₁ <α ₃ and
0.030 ≧ (α ₁ D _i −α ₃ D _p ) ΔT + (D _i −D _p ) ≧ 0.003
The element forming member according to claim 1, wherein the element forming relationship is satisfied.   The material of the pressing member includes any one selected from the group consisting of quartz glass, glassy carbon, graphite, silicon nitride, silicon carbide, alumina, boron carbide, zirconia, tantalum carbide, molybdenum, and tungsten. Item 6. The element molding member according to any one of Items 1 to 5. 7. The body according to claim 1, wherein the body mold includes at least 90% by mass or more of a material having a thermal expansion coefficient of 1.0 × 10 ⁻⁷ (/ ° C.) to 3.5 × 10 ⁻⁶ (/ ° C.). The element forming member according to claim 1.   The element molding member according to claim 1, wherein the body mold includes at least 90 mass% or more of quartz glass.   The element forming member according to claim 1, wherein the body mold includes at least 90 mass% or more of silicon nitride.   10. The element forming device according to claim 1, wherein at least a sliding surface facing the inner peripheral surface of the body mold among the outer peripheral surfaces of the mold is made of a material containing carbon. Element.   In the mold, an R chamfering process or a C chamfering process of 0.2 mm or more and 1.0 mm or less is performed on an edge portion where the sliding surface and a pressing surface that presses the material intersect. 10. A member for forming an element according to 10.   The element forming member according to claim 10 or 11, wherein the material containing carbon includes any one selected from the group consisting of graphite, glassy carbon, DLC, and diamond. The laminated element further includes a frame mold for adjusting a position of a material constituting the element between the pair of molds,
The element forming member according to any one of claims 1 to 12, wherein the frame mold is made of a ceramic having a bending strength of 300 MPa or more.   The element forming member according to claim 13, wherein the frame mold is made of a material including any one selected from the group consisting of silicon carbide, silicon nitride, alumina, boron carbide, zirconia, and tantalum carbide.   The manufacturing method of the element using the member for element shaping | molding of any one of Claims 1-14.   The element shape | molded using the member for element shaping | molding of any one of Claims 1-14.

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