JP2008024533A - Mold for molding optical device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mold for molding an optical device by which heat transfer to a glass base material to be molded is efficiently carried out without causing heat loss. <P>SOLUTION: The mold for molding the optical device is provided with a pair of upper and lower dies 11 and 12 respectively having flanges 11a and 12a, an internal drum die 13 for controlling a pair of the upper and lower dies 11, 12 to position coaxially and an outer drum die 14 positioned outside of the inner drum die 13 and for controlling the thickness of the glass optical device 15 molded by pressing the glass base material to be molded with a pair of the upper and lower dies 11, 12. A flange part 13a projecting outward is formed at the lower end part of the inner drum die 13 and is in close contact with the flange 12a of the lower die 12 and the lower end part of the outer drum die 14 is in close contact with the flange 13a. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an optical element molding die for manufacturing an optical element used in an optical apparatus by molding.

  A conventional optical element molding die of this type has been configured as shown in FIG. In FIG. 5, 1 is an upper mold having a flange 1a, 2 is a lower mold having a flange 2a, and this lower mold 2 constitutes a pair of upper and lower molds 1, 2 with the upper mold 1. Yes. Reference numeral 3 denotes an internal cylinder mold that coaxially regulates the pair of upper and lower molds 1 and 2, and 4 is positioned outside the internal cylinder mold 3 and is press-molded by the pair of upper and lower molds 1 and 2. The outer body mold 4 defines the thickness of the glass optical element 5. The outer body mold 4 has a flange portion 4 a that protrudes inwardly at the lower end portion, and the flange portion 4 a is a flange of the lower mold 2. The lower end portion of the inner trunk mold 3 is brought into close contact with the flange section 4 a of the outer trunk mold 4.

  Next, a method for manufacturing an optical element using the optical element molding die will be described with reference to FIGS. 6A, 6B, 7A, 7B, and 8A, 8B. To do.

  FIG. 6A is a view showing a state in which the lower mold 2 is lowered in order to supply the glass material to be molded into the optical element molding die. As is clear from this figure, the glass to be molded is also shown in FIG. The material 6 is placed on the molding surface 7 of the lower mold 2 using a glass holding jig (not shown) or the like.

  The lower mold 2 on which the glass material 6 to be molded is placed is lifted into the hole portion of the external body mold 4 by lifting means such as a cylinder (not shown) as shown in FIG. Then, it is guided by the inscribed surface 4b in the flange portion 4a of the outer body mold 4 and slides to a predetermined position.

  When the lower mold 2 is further pushed upward by a cylinder (not shown) or the like, as shown in FIG. 7A, the lower end surface 1c of the upper mold 1b and the glass material 6 to be molded come into contact with each other. Then, the upper mold 1 is lifted and the flange 1 a of the upper mold 1 is separated from the outer body mold 4. In this state, the glass material 6 to be molded is heated to a predetermined temperature to be softened, and in the state in which the heat softening is performed, the upper mold 1 is pushed in by a cylinder (not shown) or the like, and FIG. The glass optical element 5 is molded by pressurizing the glass material 6 to be molded.

  Next, in the state shown in FIG. 7B, the pressure-molded glass optical element 5 is cooled until it becomes below the glass transition point. When this cooling is started, heat shrinkage occurs in the outer body mold 4, so the upper mold 1 descends following the heat shrinkage of the outer body mold 4. Thereby, the lower end surface 1c of the upper mold lower portion 1b can maintain contact with the glass optical element 5 during cooling, as shown in FIG. 8A. Then, the upper die lower portion 1b substantially in contact with the inner drum die 3 is in a state where the approach direction with the lower die 2 is regulated by the inner drum die 3 due to the heat shrinkage of the outer drum die 4. It descends parallel to the optical axis direction of the mold 1. Thereby, the glass optical element 5 after mold release becomes a thing with little inclination, and has a favorable precision.

  When the glass optical element 5 is cooled to a predetermined temperature (below the glass transition temperature), the lower mold 2 is lowered to release the glass optical element 5 as shown in FIG. 8B. In this mold release, the glass optical element 5 placed on the molding surface 7 of the lower mold 2 is taken out using a suction pad (not shown) or the like.

As prior art document information relating to the invention of this application, for example, Patent Document 1 is known.
JP 2002-29763 A

  In the above-described conventional optical element molding die, when the glass material 6 to be molded is heated and softened to a predetermined temperature, the state shown in FIG. 7A, that is, the lower end surface 1c of the upper mold lower portion 1b and the workpiece. The glass material 6 to be molded is heated and softened to a predetermined temperature in a state where the glass material 6 comes into contact and the upper mold 1 is lifted and the flange portion 1a of the upper mold 1 is separated from the external body mold 4. However, in the conventional optical element molding die, a flange portion 4a protruding inwardly is formed at the lower end portion of the outer body die 4, and this flange portion 4a is formed on the flange 2a of the lower die 2. Since the lower end portion of the inner barrel mold 3 is brought into close contact with the flange portion 4a of the outer barrel mold 4, heat from a heating block (not shown) provided below the lower mold 2 is used. Is transmitted to the flange 2a of the lower mold 2 and From the lever flange 2a through the flange portion 4a of the outer trunk mold 4 and the outer trunk mold 4 to the inner trunk mold 3, and then to the glass material 6 to be molded, heat transfer paths increase, In the meantime, some escape from the external body mold 4 occurs, and thus there is a problem that the efficiency of heat transfer to the glass material 6 to be molded is poor.

  The present invention solves the above-described conventional problems, and an object thereof is to provide an optical element molding die that can efficiently perform heat transfer to a glass material to be molded without causing heat loss. To do.

  In order to achieve the above object, the present invention has the following configuration.

  The invention described in claim 1 of the present invention is a pair of upper and lower molds having flanges, an inner trunk mold for coaxially regulating the pair of upper and lower molds, and an outer side of the inner trunk mold. And an outer cylinder that defines the thickness of a glass optical element that is molded by pressing a glass material to be molded by the pair of upper and lower molds, and a flange portion that protrudes outward at the lower end of the inner cylinder And the flange portion is brought into close contact with the flange of the lower mold, and the lower end portion of the outer barrel mold is brought into contact with the flange portion. According to this configuration, the lower end of the inner barrel mold is formed. A flange portion that protrudes outward is formed on this portion, and this flange portion is brought into close contact with the flange of the lower mold, and the lower end portion of the external body mold is brought into contact with this flange portion. The heat from the lower heating block It is transferred from the flange to the glass material to be molded through the flange portion of the inner trunk mold and the inner trunk mold, thereby shortening the heat transmission path and the conventional outer barrel mold. Since no heat loss occurs, the heat transfer to the glass material to be molded can be efficiently performed.

  As described above, the optical element molding die of the present invention forms a flange portion projecting outward at the lower end portion of the inner body die, and this flange portion is brought into close contact with the flange of the lower die, and this flange Since the lower end of the outer body mold is in contact with the part, the heat from the heating block provided below the lower mold is transferred to the flange of the lower mold, and from this flange, the flange part of the inner body mold The heat is transferred to the glass material through the body mold, which shortens the heat transfer path and does not cause heat loss from the external body mold. This provides an excellent effect that transmission can be performed efficiently.

  Hereinafter, an optical element molding die according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view of an optical element molding die according to an embodiment of the present invention. FIGS. 2 (a) and 2 (b), FIGS. 3 (a) and 4 (b), and FIGS. It is a manufacturing process figure which shows the process of manufacturing an optical element using the element shaping die.

  In FIG. 1, 11 is an upper mold having a flange 11 a, 12 is a lower mold having a flange 12 a, and this lower mold 12 forms a pair of upper and lower molds 11, 12 with the upper mold 11. Yes. Reference numeral 13 denotes a hollow cylindrical inner cylinder that coaxially regulates the pair of upper and lower molds 11 and 12, and 14 is located outside the inner cylinder 13 and is formed by the pair of upper and lower molds 11 and 12. It is a hollow cylindrical outer cylinder that defines the thickness of the glass optical element 15 to be pressure-molded. The inner body mold 13 is formed with a flange portion 13a projecting outward at the lower end, and the flange portion 13a is brought into close contact with the flange 12a of the lower mold 12, and the outer body mold is formed on the flange portion 13a. 14 is in contact with the lower end.

  Next, a method for manufacturing an optical element using the optical element molding die will be described with reference to FIGS. 2A, 2B, 3A, 3B, and 4A, 4B. To do.

  FIG. 2A is a view showing a state in which the upper mold 11 is pulled upward in order to supply the glass material to be molded into the optical element molding die. As is clear from this figure, the glass to be molded is also shown in FIG. The material 16 is placed on the molding surface 17 of the lower mold 12 using a glass holding jig (not shown) or the like. In this case, the relationship between the lower mold 12, the internal cylinder mold 13 and the external cylinder mold 14 is such that the internal cylinder mold 13 is fitted to the lower mold upper portion 12b, and the flange portion 13a of the internal cylinder mold 13 is the lower mold 12. The outer cylinder mold 14 is positioned outside the inner cylinder mold 13 and the lower end portion of the outer cylinder mold 14 is in contact with the flange section 13 a of the inner cylinder mold 13.

  From the state shown in FIG. 2 (a), the upper mold 11 is pushed down by lifting means such as a cylinder (not shown), and the upper mold lower part 11b is formed as an internal body mold as shown in FIG. 2 (b). 13 enters the hollow portion 13 and is guided to the inner peripheral surface 13b of the inner body mold 13 to slide to a predetermined position.

  When the upper mold 11 is further pushed down by a cylinder (not shown) or the like, as shown in FIG. 3A, the end surface of the lower end portion 11c of the upper mold lower portion 11b, the glass material 16 to be molded, Touch. In this state, the flange 11a of the upper mold 11 and the external body mold 14 are separated from each other. In this state, the glass material 16 to be molded is heated to a predetermined temperature and softened. In this heat softening, heat from a heating block (not shown) provided above the upper mold 11 and a heating block (not shown) provided below the lower mold 12 is transmitted to the glass material 16 to be molded. By doing. In this case, heat from a heating block (not shown) provided below the lower mold 12 is transmitted to the flange 12a of the lower mold 12, and the flange portion 13a of the internal cylinder mold 13 and the internal cylinder mold are transmitted from the flange 12a. 13 to the glass material 16 to be molded. Then, with this heat softening, the upper mold 11 is pushed in by a cylinder (not shown) or the like, and the glass material 16 is pressed to the state shown in FIG. To do.

  Next, in the state shown in FIG. 3B, the pressure-molded glass optical element 15 is cooled until it becomes below the glass transition point. When this cooling is started, heat shrinkage occurs in the outer body mold 14, and the upper mold 11 descends following the heat shrinkage of the outer body mold 14. Thereby, as shown to Fig.4 (a), the molding surface 11c of the upper metal mold | die 11 can maintain a contact with the glass optical element 15 during cooling.

  Then, when the glass optical element 15 is cooled to a predetermined temperature (below the glass transition temperature), the upper mold 11 is pulled upward and separated from the glass optical element 15 as shown in FIG. Thereafter, the glass optical element 15 placed on the molding surface 17 of the lower mold 12 is taken out using a suction nozzle (not shown) or the like.

  In the above-described embodiment of the present invention, the flange portion 13a protruding outward is formed at the lower end portion of the inner body mold 13, and the flange portion 13a is brought into close contact with the flange 12a of the lower mold 12, Since the lower end portion of the outer body die 14 is brought into contact with the flange portion 13 a of the inner body die 13, heat from a heating block (not shown) provided below the lower die 12 is generated by the lower die 12. It is transmitted to the flange 12a, and is transmitted from the flange 12a to the glass material 16 to be molded through the flange portion 13a of the inner body mold 13 and the inner body mold 13, thereby shortening the heat transfer path and Thus, heat loss from the external body mold 4 as described above does not occur, so that heat transfer to the glass material 16 to be molded can be performed efficiently.

  In the optical element molding die according to the present invention, when heat is transmitted from a heating block (not shown) provided below the lower die to the glass material to be molded, the heat transmission path can be shortened. It has the effect of being able to efficiently transfer heat to the glass material to be molded without causing heat loss from the external body mold as in the prior art, and particularly used in a method of manufacturing an optical element. This is useful.

Sectional drawing of the optical element shaping die in one embodiment of this invention (A) (b) Manufacturing process figure which shows the process of manufacturing an optical element using the optical element shaping die (A) (b) Manufacturing process figure which shows the process of manufacturing an optical element using the optical element shaping die (A) (b) Manufacturing process figure which shows the process of manufacturing an optical element using the optical element shaping die Sectional view of a conventional mold for molding optical elements (A) (b) Manufacturing process figure which shows the process of manufacturing an optical element using the optical element shaping die (A) (b) Manufacturing process figure which shows the process of manufacturing an optical element using the optical element shaping die (A) (b) Manufacturing process figure which shows the process of manufacturing an optical element using the optical element shaping die

Explanation of symbols

11 Upper mold 11a Flange 12 Lower mold 12a Flange 13 Internal body mold 13a Flange part 14 External body mold 15 Glass optical element 16 Molded glass material

Claims (1)

A pair of upper and lower molds having flanges, an internal cylinder mold that coaxially regulates the pair of upper and lower molds, and a glass material to be formed by the pair of upper and lower molds that is located outside the internal cylinder mold And an outer cylinder mold that defines the thickness of the glass optical element that is molded by pressurizing and forming a flange portion that protrudes outward at the lower end of the inner cylinder mold, and this flange section is formed on the lower metal plate. An optical element molding die in which the flange of the mold is brought into close contact with the lower end of the outer body mold in contact with the flange.

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