JP2006143586A - Method for drawing adsorber for formed body, method for drawing press formed body, and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To smoothly perform the drawing of a press formed body from a forming die. <P>SOLUTION: Using an adsorber 22 equipped with: an adsorbing member 24 provided with an adsorbing face for adsorbing a press formed body 16; a support 26 of supporting the adsorbing member 24 movably to the upper and lower directions; a sucking means of sucking gas from the absorbing face; and an elevating/lowering means of elevating/lowering the support, the press formed body formed by a forming device is drew. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a precision press molding technique for pressing a material to be molded such as glass to form a highly accurate press molded body such as an aspheric lens, and in particular, it is easy to take out the press molded body from the mold after pressing. The present invention relates to an adsorbing device and a taking-out method for a molded body, and a taking-out method and a manufacturing method for a press-formed body.

  In recent years, precision press molding of press-molded bodies such as high-precision optical elements that do not require grinding and polishing after press molding has been actively performed. Precision press molding uses a molding die including an upper die and a lower die, and a molding material such as glass is placed in a cavity surrounded by the upper and lower molding surfaces and the peripheral surface between them, and the upper and lower molds move relative to each other. Is pressed to obtain a press-molded body such as an aspherical lens.

  In press molding, a molding method that does not require grinding or polishing of the outer peripheral surface of a press-molded body is known. In this type of press molding, the material to be molded is stretched to the peripheral surface of the cavity constituted by the lower mold or the barrel mold, thereby defining the outer periphery of the press molded body.

  After pressing, the press-molded body is taken out from the mold by vacuum-sucking the press-molded body from above and pulling it up. In this type of press molding, in order to improve the productivity of the press-molded body, it is preferable to take out the press-molded body as soon as possible after pressing the material to be molded. In this case, press molding after pressing When the body is near the glass transition point (Tg), it is desired to take it out.

  However, in this type of press molding, as long as the press-molded body is still in the vicinity of Tg, the glass does not shrink to such an extent that it naturally separates from the mold. Even if it is in close contact or has only a very narrow gap and it is attempted to take out the press-molded body, it is very difficult to remove it because of the negative pressure between the glass molded body and the lower mold surface. . In this case, the glass molded body is often in close contact with the lower molding surface, and it has been difficult to reliably remove such a glass molded body.

In addition, when the outer peripheral surface is molded by the body mold, it is very difficult to remove from the body mold if the width of the outer peripheral surface (the thickness of the edge portion) is thick. Also, if the width of the outer peripheral surface (thickness of the edge portion) is relatively thin, the direction of the glass molded body is inclined during removal from the barrel mold, making it difficult to get caught inside the barrel mold. There was also.
In this case, the edge refers to the peripheral edge of the lens. As will be described later, the press molded body preferably has a rounded free surface at the boundary between the upper and lower molding surfaces and the peripheral surface of the body mold, but the roundness has a radius of curvature of about 0.1 mm. Can be considered to be approximately equal to the width of the outer peripheral surface.

  Accordingly, an object of the present invention is to provide a molded body adsorption device and a method for removing a molded body that can be easily taken out from the mold.

  Another object of the present invention is to provide a method for taking out a press-molded body and a method for producing the same, which can easily remove the press-molded body from the mold and prevent the press-molded body from being damaged.

  In order to achieve the above object, an adsorption device for adsorbing a molded body of the present invention includes an adsorption member having an adsorption surface for adsorbing the molded body, and a support for supporting the adsorption member so as to be movable in the vertical direction. The suction device includes a body, suction means for sucking gas from the suction surface, and lifting means for lifting and lowering the support.

  Here, the outer diameter of the suction surface of the suction member is made larger than the inner diameter of the cavity for molding the molded body, and the suction holes formed in the suction surface are made smaller than the outer diameter of the molded body. Can do. The outer diameter of the suction surface of the suction member may be smaller than the inner diameter of the cavity that molds the molded body, and the suction hole formed in the suction surface may be smaller than the outer diameter of the molded body. it can.

  In order to achieve the above object, the method for taking out the molded body of the present invention is a method for taking out the molded body molded by the molding apparatus using the above-described adsorption device.

  In order to achieve the above object, the method for taking out the press-formed body of the present invention is a press formed by a press-forming die having a cavity surrounded by a forming surface of the upper and lower molds and a peripheral surface located on the outer peripheral side thereof. It is a method of taking out a molded object using the molded object adsorption | suction apparatus of Claim 1 or 2, Comprising: After separating the molding surface of the said upper mold | type from the said press molded object, the said adsorption member makes the said press molding die. It is a method of closing and further sucking the gas in the cavity to adsorb the press-molded body on the adsorption surface and take out the press-molded body from the press mold.

  Moreover, in this invention, it can be set as the method of attracting | sucking the said press molded object to an adsorption | suction surface by attracting | sucking the gas in the said cavity and making the said press molded object in the said cavity float.

  Moreover, in this invention, when the said press-molded body is adsorbed by the said adsorption member, it can be set as the method to which the said adsorption member moves up and down with respect to the said support body.

  Moreover, in this invention, taking out of the said press molded object can be made into the method which starts when the said press molded object is the temperature range of Tg-50 degreeC-TgC.

  In order to achieve the above object, the method for producing a press-molded body of the present invention is a method of pressing the soft material to be molded and molding the press-molded body, and then taking out the press-molded body with the adsorption device. .

  Further, the method for producing a press-molded body of the present invention presses a soft material to be molded by a press mold having a cavity surrounded by upper and lower mold surfaces and a peripheral surface located on the outer peripheral side thereof. Then, the press molded body is molded, and after the molding surface of the upper mold is separated from the press molded body, the press molded body is taken out by the method of taking out the press molded body.

In the press molding in the present invention, for example, after the upper shaft and / or the lower shaft of the press is driven to place the molding die in the induction heating coil, induction heating is performed and the molding material is heated to the molding temperature. The upper shaft and / or the lower shaft may be driven to further press the upper die and the lower die.
The glass material to be molded may be heat-softened after being supplied to the mold, but is preferably supplied to the mold in a heat-softened state in advance. When supplying in a heat-softened state, it is preferable to heat the mold in advance. In particular, it is a method of supplying a glass material to be molded, which has been softened by heating in advance, to the mold, and the glass optical material having no surface defects or the like that the temperature of the glass material to be molded supplied to the mold is higher than the temperature of the mold It is preferable from the viewpoint that the element can be manufactured in a relatively short cycle time.

For example, the glass material can be softened by heating at a temperature corresponding to a viscosity of the glass material of less than 10 ⁹ poise. If the viscosity of the glass material is less than 10 ⁹ poise, it is possible to mold by deforming the glass material in the mold preheated to a temperature corresponding to a viscosity of more than ¹⁰⁹ poises. The glass material is more preferably softened by heating to a temperature corresponding to 10 ^5.5 to 10 ^7.6 poise, and more preferably 10 ^6.5 to 10 ^7.5 poise. is there. It is preferable from the viewpoint of shortening the cycle time that the temperature of the preheating of the mold is lower than that of the glass material so that the viscosity at which the glass can be released is reached quickly. If the viscosity is less than a temperature corresponding to 10 ¹² poise, it is difficult to obtain a glass molded body with a thin edge by greatly stretching the glass material, and it is difficult to obtain high surface accuracy, and the viscosity corresponds to 10 ⁹ poise. Above the temperature, the cycle time of the shape becomes longer than necessary, and the life of the mold is shortened. More preferably, it is 10 ⁸ to 10 ^10.5 poise.

  The supply of the mold for forming the glass to be formed may be performed by using a known supply means such as a transfer hand having an adsorbing means. However, when the glass to be formed is supplied in a heated and softened state, it is preferably placed on a floating plate. In addition, a plurality of glass forming materials that are floated and softened by air flow ejected from below are floated and transferred, and the glass forming material is dropped by dividing the floating plate directly above the lower mold. Can supply the glass material. As such a floating dish, for example, the one described in JP-A-8-133758 can be used.

  In a low-viscosity region where the glass material is deformed by its own weight, it is not easy to prevent the glass holding the glass material from fusing with each other during heating. When a glass plate is levitated by an air flow using a levitation dish that ejects gas from the inside of the jig, a gas layer is formed on both the jig surface and the glass surface. It becomes possible to soften. Furthermore, when the glass material is a preform, it can be softened by heating while maintaining the shape of the preform in general. In addition, even if the glass material is a glass hump and has irregular shapes and surface defects such as wrinkles, the shape can be adjusted and the surface defects can be eliminated by floating with an air flow while softening with heat. It is.

  There is no restriction | limiting in particular as gas used as the airflow used for levitation | floating of a glass raw material. However, from the viewpoint of preventing the heated glass material from reacting with the jig and preventing deterioration of the heated jig due to oxidation, it is preferably a non-oxidizing gas, for example, nitrogen. is there. A reducing gas such as hydrogen gas can also be added. The flow rate of the airflow can be appropriately changed in consideration of the shape of the mouth for blowing out the airflow, the shape and weight of the glass material, and the like. In a normal case, a gas flow rate in the range of 0.005 to 20 liters / minute is suitable for floating a glass material. However, if the gas flow rate is less than 0.005 liter / min, the glass material may not be sufficiently levitated when the weight of the glass material is 300 mg or more. In addition, when the gas flow rate exceeds 20 liters / minute, even when the glass weight is 200 mg or more, the glass on the floating jig is greatly shaken, and when the glass material is a preform for heating, the shape may change. Because there is. Furthermore, the heating change condition of the glass material can be appropriately changed depending on the type of glass and the like, and is adjusted so as to have a viscosity required for the softened glass material.

  The levitation by the air flow of the preform can be performed, for example, by an air flow flowing upward from an upper opening having an opening diameter smaller than, equal to, or larger than the diameter of the preform. Furthermore, when using the split mold floating plate as described above, the glass material to be molded is disposed between the floating plate and the lower mold in order to drop the center of the lower mold without being misaligned. It can also be dropped through the opening of the slip prevention funnel member. Moreover, in order to correct the position shift from the lower mold center part of the glass molding material which fell, the center shift | offset | difference can also be correct | amended by performing width alignment by a guide means.

  Examples of the shape of the material of the glass to be molded that can be applied in the present invention include a spherical shape and a marble shape. Moreover, examples of the glass optical element obtained by molding the material of the glass material to be molded include an aspherical or spherical biconvex lens, a convex meniscus lens, and a concave meniscus lens.

In the present invention, there are no particular limitations on the conditions for press molding, and the conditions can be appropriately determined in consideration of the temperature of the glass material and the temperature of the mold. Usually, it can be molded by pressing at a pressure of 30 to ²⁰ kg / cm ² for 3 to 60 seconds, preferably 5 to 30 seconds.

  In press molding, the glass does not come into contact with the boundary between the molding surface of the upper mold and / or the lower mold and the peripheral surface of the body mold, that is, the glass forms a free surface on the mold in the portion. It is preferable from the viewpoint of preventing the glass from flowing into the boundary portion. In this case, it is particularly preferable to provide an opening of the air passage at the boundary between the molding surface of the lower die and the peripheral surface of the body die from the viewpoint of preventing glass from flowing into the air passage.

  After press molding, when the viscosity of the molded glass does not greatly deform even when the upper mold is released, for example, the viscosity corresponds to a temperature of Tg + 20 ° C. or lower, opening the mold as soon as possible, that is, releasing the upper mold, shortens the cycle time. It is preferable from the viewpoint. At this time, the mold opening timing can be appropriately selected depending on the shape and glass type of the press-molded body, but preferably the upper mold is released when it is in the range of Tg to Tg + 20 ° C. Opening is preferred.

  The press-molded body separated from the upper molding surface is on the lower molding surface, and at least a part thereof is within the peripheral surface. The step of taking out the press-molded body in this state from the lower molding surface is to shorten the cycle time by taking out the press-molded body as soon as possible when it reaches a viscosity that does not greatly deform even when the press-molded body is taken out, for example, a viscosity corresponding to a temperature of Tg or less. It is preferable from the viewpoint. At this time, the timing of taking out the press-molded body can be appropriately selected depending on the shape of the press-molded body and the glass type, but the range of Tg-50 ° C to Tg ° C is more preferable.

  As described above, according to the present invention, it is possible to smoothly remove the press-molded body from the mold.

Hereinafter, the present invention will be described in detail based on the illustrated embodiment.
In the following description, the present invention will be described along a press molding method using a mold unit configured separately from the press molding apparatus. However, it will be apparent from the following description that the present invention can be applied to a method other than the method using the mold, that is, the apparatus in which the mold is fixedly provided in the press molding apparatus.

FIG. 1 shows a cross-sectional view of a mold unit in which an adsorption device according to the present invention is used.
The mold unit 10 is a unit body that is composed of an upper mold 12 and a lower mold 14 and independent of the press molding apparatus. In the mold unit 10, the upper mold 12 and the lower mold 14 are fitted together to form one unit body. The upper mold 12 and the lower mold 14 are provided with molding surfaces (hereinafter referred to as an upper molding surface 12a and a lower molding surface 14a, respectively) on the opposite side, and a molding peripheral surface 14b is provided between the upper and lower molding surfaces 12a and 14a. A cavity 16 is formed in the mold unit 10 by the molding surfaces 12a and 14a and the molding peripheral surface 14b. As will be described later, in a state where the spherical glass material G is disposed in the cavity 16, the mold unit 10 is carried into a press molding apparatus and pressed to obtain a glass molded body. A plurality of mold units 10 are prepared for one press molding apparatus, and these are sequentially supplied to the press molding apparatus, thereby forming a production line that enables continuous production of a glass molded body. In a preferred embodiment, each component of the mold is formed of silicon carbide, and the upper and lower molding surfaces and the molding peripheral surface are coated with a carbon-based release film.

  The upper mold 12 includes an upper mold body 12A having an upper molding surface 12a on the lower surface, a cylindrical upper mold sleeve 12B, a release ring 12C, and a spring 12D covering the periphery of the upper mold body 12A. The upper mold body 12A and the sleeve 12B are cast separately and then integrated, and the release ring 12C and the spring 12D are accommodated in the space between them. The release ring 12C and the spring 12D act so as to pull up the upper mold 12 with respect to the lower mold 14 after pressing.

  The lower mold 14 includes a lower mold body 14A having a lower molding surface 14a and a lower mold sleeve 14B. The lower die body 14A and the lower die sleeve 14B are integrated after being separately cast. The lower mold sleeve 14B includes a molding peripheral surface 14b along the inner peripheral surface at the upper portion thereof. In an assembled state of the mold unit 10, the upper part of the lower mold sleeve 14B having the molding peripheral surface 14b is fitted into the inner peripheral side of the upper mold sleeve 12B. A cavity 16 is formed by the molding peripheral surface 14b, the lower molding surface 14a, and the upper molding surface 12a of the upper mold 12 of the lower mold 14.

  The mold unit 10 further includes an air passage 18 that communicates the cavity 16 and the outside of the mold unit 10 along the radial direction thereof. The air passage 18 is composed of a plurality of air passages extending radially in the radial direction when the mold unit 10 is viewed in plan view. FIG. 2 is an enlarged view of the main part of FIG. 1, in which the air passage 18 is clearly shown. In the present embodiment, the ventilation path 18 includes a ventilation gap 18a formed by the lower mold body 14A of the lower mold 14 and the lower mold sleeve 14B, a passage 18b formed through the lower mold sleeve 14B, and the lower mold sleeve 14B. And the vent groove 18c formed on the fitting surface of the upper sleeve 12B. As will be described later, when the glass material G to be molded is pressed, the air in the cavity 16 is discharged out of the mold unit 10 through the air passage 18. Further, when the glass molded body G after pressing is taken out, air is introduced from the outside of the mold unit 10 into the cavity 16 through the air passage 18.

  That is, in press molding using the mold unit 10, the glass material G to be molded disposed in the cavity 16 is pressed and spreads laterally by the approach of the upper mold 12 with respect to the lower mold 14, and its peripheral surface is lower. It is formed by the molding peripheral surface 14b of the mold sleeve 14B. As the press progresses, the contact area of the peripheral surface of the glass material G to be formed with the molding peripheral surface 14b increases, and the area in space gradually decreases. By releasing the air in the cavity 16 to the outside through the air passage 18, it is possible to prevent a gas trap from occurring on the molding surface and an abnormally high pressure in the molding surface, thereby minimizing the influence on the glass molded body. Can be. The action of the air passage 18 at the time of taking out the glass molded body G will be described later.

  FIG. 3 shows an apparatus configuration when the glass mold G is pulled up after the upper mold 12 and the lower mold 14 are separated after pressing, and this figure will be referred to in the following description. After pressing the glass material G to be molded, a process of separating the mold unit 10 not shown in the figure, that is, lifting the upper mold 12 with respect to the lower mold 14 is performed after a predetermined cooling period. A step of taking out the compact G is performed. In carrying out this step, the lower mold 14 is fixed on the support base 32 by the vacuum chuck mechanism. The glass molded body G is taken out by an adsorption device 22 having an adsorption mechanism. The suction device 22 includes a suction pad 24 of a support 26, a lifting device and a suction device (not shown). The suction pad 24 has a suction hole 24a on its lower surface and a collar portion 24b on its upper part. Here, the diameter of the lower surface is formed larger than the diameter of the cavity 16, that is, the inner diameter of the molding peripheral surface 14b. As a result, as shown in the figure, the lower surface is in contact with the upper surface of the lower mold sleeve 14B, closes the air passage 18, and allows the glass molded body G to be adsorbed by the adsorbing holes 24a. The suction pad 24 is suspended and supported by the receiving portion 26a of the support body 26 at the collar portion 24b. At this time, there is some play in the vertical direction between the collar portion 24b of the suction pad 24 and the receiving portion 26a, so that the suction pad 24 can move slightly up and down with respect to the support 26. To be.

Next, an embodiment of a method for taking out a press-formed body of the present invention will be described.
The step of taking out the glass molded body is started when the temperature of the molded body is preferably in the temperature range of Tg ° C to Tg-50 ° C. In this case, the temperature of the molded body can be controlled by the temperature in the vicinity of the molding surface of the upper mold and / or the lower mold (for example, a position at a depth of 5 mm from the molding surface) with the temperature of the press molded body.

  In the step of taking out the glass molded body, first, the lower surface of the suction pad 24 is placed on the upper surface of the lower mold sleeve 14B, and the cavity 16 is closed. Next, by starting a suction device (not shown), the glass molded body G is pulled up and sucked by the suction holes 24a. At this time, when the upper surface of the lower mold sleeve 14B is adjusted to be a surface perpendicular to the optical center of the upper and lower molding surfaces, the lower surface of the suction pad 24 is relative to the optical center of the glass molded body. Therefore, the suction pad is arranged with high positional accuracy with respect to the glass molded body, and the glass molded body can be more accurately attracted.

  When the glass molded body G is pulled up by the adsorption device 22, the air passage 18 allows air to flow downward around the glass molded body G in the cavity 16. For this reason, the space of the ventilation path 18 below the glass molded body G does not become negative pressure, and the smooth rise of the glass molded body G by the suction is achieved. The operation in this step will be described in detail later. The air passage 18 has a suction force applied to the suction means and the press-molded body by a negative pressure applied to the lower surface of the press-molded body in a space surrounded by at least the lower mold-molding surface, the lower surface of the press-molded body, and the peripheral surface. However, it is important to communicate with the outside of the space so that the gas can be supplied to the space through the air passage so that the space is always exceeded, in order to reliably take out the press-formed body by the adsorption means. In this case, injecting high-pressure gas from the air passage is also effective for the method of supplying gas.

Next, each step in the embodiment of the method for producing a press-formed body according to the present invention will be described.
4-7, each process (A)-(H) of press molding is shown.
Steps (A) and (B) of FIG. 4 show the respective steps of accommodating the glass material G to be molded in the mold unit 10. That is, in FIG. 1A, the molding unit 10 has a spherical molded glass in which only the lower mold 14 is left on the support base 32 and is adsorbed by the glass carry-in pad 40 on the lower molding surface 14a. Material G is placed. Next, the support base 32 is transferred, and the lower mold 14 on which the glass material G to be molded is placed is brought under the upper mold 12 supported by a support means (not shown). Next, as the support base 32 is raised, the lower mold 14 is fitted into the lower part of the upper mold 12, whereby the glass material G to be molded is accommodated in the cavity 16 of the mold unit 10 as shown in FIG. It is done.

  Next, the mold unit 10 containing the glass material G to be molded is carried into a press molding apparatus (not shown). A heating zone, a press zone, and a cooling zone are provided in the press molding apparatus, and each of these regions is maintained in a non-oxidizing atmosphere. In the heating zone, the mold unit 10 is heated at a predetermined temperature for a predetermined time, whereby the glass material G to be molded inside is heated and softened. Next, the mold unit 10 is transferred to the press zone, where the glass material G to be molded is pressed.

  Steps (C) and (D) in FIG. 5 show steps in the press zone of the press molding apparatus. In the step (C), the mold unit 10 is placed between the upper and lower press heads 42 and 44, and the upper press head 42 is lowered in the step (D), so that the upper and lower mold forming surfaces 12a and 14a are moved. The glass material to be molded G is pressed, and a desired glass molded body G is obtained. That is, when the upper mold 12 is lowered with respect to the lower mold 14 by the lowering of the upper press head 42, the glass material G to be molded in the cavity 16 is crushed and has a shape along the molding surface of each mold. A glass molded body G is obtained. At this time, the outer periphery of the glass molded body G reaches the molding peripheral surface 14b, where the periphery of the glass molded body G is defined and the outer peripheral surface is formed. The lowering of the upper press head 42 is stopped at a position where the lower surface of the upper mold sleeve 12B is abutted against the upper surface of the lower mold sleeve 14B. This ensures that the thickness of the glass molded body G to be formed is constant.

  In this pressing step, air in the cavity 16 is discharged out of the mold unit 10 from the air passage 18 formed in the mold unit 10 and functions to eliminate the influence of air pressure in the press operation. When the upper press head 42 is lifted with respect to the mold unit 10 after this pressing, the urging force of the spring 12D works, and the upper mold 12 is pulled upward with respect to the lower mold 14 and the glass molded body G by this force. The upper molding surface 12a and the upper surface of the glass molded body G are separated. After pressing the glass material G to be molded, the mold unit 10 is transferred to a cooling zone in the press molding apparatus, cooled here, and then carried out of the apparatus and passed to the next step.

  Steps (E) to (H) of FIGS. 6 and 7 show steps for taking out the glass molded body G from the mold unit 10. In step (E), the mold unit 10 carried out from the press molding apparatus is transferred to an area where a step for taking out the glass molded body G is performed. In the area, as described above with reference to FIG. 3, the lower die 14 is sucked and fixed to the support base 32, and the upper die 12 is sucked to the sucking and conveying device 34. The upper mold 12 is pulled up from the lower mold 14 by the suction conveyance device 34 and retracted to another place. Next, in the step (F), the suction device 22 is lowered to the upper surface of the lower mold sleeve 14B. Thereby, the open | released upper part in the cavity 16 where the glass forming body G is arrange | positioned is obstruct | occluded by the lower surface of the suction pad 24. FIG.

  Next, in step (G), when a suction device (not shown) is activated and the suction pad 24 starts to be pulled up from the suction hole 24a, the space immediately below becomes negative pressure, and the glass forming in the air passage 18 is performed. The body G receives a force pulled upward. At this time, the glass molded body G may be in close contact with the lower molding surface 14a and the molding peripheral surface 14b. Air is introduced from the outside and guided to the space below the cavity 16. As a result, the glass molded body G is less likely to stop in the cavity 16, and the glass molded body G is smoothly taken out by the adsorption device 22. Further, in the suction device 22 according to the present embodiment, the impact when the glass molded body G is sucked to the suction pad 24 is minimized by the play in the suction pad 24 and the support body 26. That is, when the glass molded body G is attracted to the suction pad 24, the suction pad 24 is retracted by the pressing and relaxes the force.

  Finally, in the step (H), the support body 26 is pulled up by a lifting device (not shown), and the glass molded body G can be completely removed from the mold unit 10. Thus, a series of operations in the step of taking out the glass molded body G after the press from the supply of the glass material G to be molded is completed. After taking out the glass molded body G, this process is cyclically performed by supplying the glass material G to be molded onto the lower mold 14 according to the process (A) of FIG.

FIG. 8 is a diagram of a glass molded body taking-out process using an adsorption device according to another embodiment of the present invention.
Taking out the glass molded body using the adsorption device according to the present embodiment is relatively suitable for taking out a glass body G having a relatively thin edge, for example, an edge having a thickness of 0.6 mm or less. This is because the orientation of the molded body is difficult to tilt because it is taken out while contacting the suction pad using the positioned suction member. As in the previous embodiment, the suction device 80 in this embodiment includes a support 82, a suction pad 84, a lifting device and a suction device (not shown), and the diameter of the lower surface of the suction pad 84 is the inner diameter of the cavity 16. And the diameter of the suction hole 84a is smaller than the diameter of the glass molded body G. For this reason, when the suction pad 84 is lowered, the lower surface of the suction pad 84 does not contact the upper surface of the lower mold sleeve 14B, and the suction hole 84a directly contacts the upper surface of the glass material G to be molded, and this can be sucked.

(The original paragraph 0049 is divided into 0048 and 0049.)
When the glass material G having a relatively thin edge is adsorbed by the suction device 22 according to the previous embodiment, the glass material G may be tilted and pulled up before reaching the suction surface of the suction pad 24. is there. The inclination of the glass material G to be molded in the cavity 16 may cause scratches or other damage on the peripheral surface, or may not be able to be taken out.
In accordance with the present embodiment, by directly contacting the suction pad 84, the glass material G to be molded in the cavity 16 can be prevented from tilting.
On the other hand, when the glass material having a relatively thick edge, for example, the width is 1 mm or more, it is preferably taken out by the adsorption device 22 according to the previous embodiment. If the edge is thick, the area where the press-molded body and the inner surface of the body die can be in contact with each other increases the friction and increases the weight of the lens. A lot is needed. In the case of the suction device 22, the outer diameter of the suction pad can be made larger than that of the body shape, so that the suction port diameter of the suction pad can be made relatively large. For this reason, since suction force can be made comparatively large, it can extract more reliably. Further, the suction device 22 capable of relatively increasing the suction force is also suitable when the adhesion between the lower mold surface and the press-molded body is large.

  In addition, this process can be performed in a press molding apparatus. By performing this step in the press molding apparatus, the time for carrying out the mold unit can be reduced, and the time from the press to the lifting of the upper mold can be shortened. In a preferred embodiment, the upper mold 12 is pulled up when the temperature of the glass molded body G is about a glass transition point of −20 ° C.

  The molding apparatus of the present embodiment uses a molding die in which four molding dies are arranged on one die base material. The upper mold base and the lower mold were formed of a tungsten alloy, and the upper mold, the lower mold, and the trunk mold were obtained by coating silicon carbide on a carbon thin film.

Using this device, barium borosilicate glass (transition point 514 ° C., yield point 545 ° C.) is pressed to form a biconvex lens with one outer diameter of 15 mm (one surface is spherical, the other surface is aspheric, edge thickness) Was 3 mm). A preform without surface defects formed into a marble shape is preheated to 470 ° C., and a transfer hand (not shown) is placed on four lower molds preheated to about 470 ° C. below the forming chamber. 4 were transferred simultaneously. Immediately, the lower mold base was raised and each barrel mold was incorporated into each upper mold at 470 ° C. At this time, the upper and lower molds were heated to 596 ° C. corresponding to a glass viscosity of 10 ⁸ poise by high frequency induction heating. After soaking, the lower base was raised and pressed at a pressure of 70 kg / cm ² until the upper and lower molding surfaces were transferred to the glass and the glass reached the peripheral surface inside the barrel mold. Next, the mold and the molded lens were cooled at a cooling rate of 50 ° C./min until the glass transition point was reached. At this time, the upper mold followed the shrinkage of the glass and cooled in a state where only the upper mold weight was applied. That is, the contact between the upper surface of the lens and the upper mold was maintained during cooling.

  In each mold, heating and cooling were performed almost evenly. The lower mother die is lowered at 490 ° C. and released, and the lower mother die is lowered to the bottom of the molding chamber. When the glass is 480 ° C., a suction member having four suction pads similar to FIG. 4 lenses were taken out at the same time. The taken out lens may be annealed afterwards if necessary. This process was repeated 100 times, but the lens could be reliably removed from the mold, and the obtained lens had high surface accuracy, good surface quality, and good eccentricity after centering.

  The embodiment of the present invention has been described with reference to the drawings. However, the present invention is not limited to the matters shown in the above-described embodiments, and it is obvious that changes, improvements, etc. can be made based on the description of the scope of claims. For example, as a molding method, in addition to press molding, a molding method to which the suction device of the present invention can be applied may be used, and the molded body is not limited to a glass lens.

It is sectional drawing which shows roughly the whole structure of the press die which applies this invention. It is a principal part enlarged view of FIG. It is the figure which showed the process of taking out a glass forming body from a shaping | molding die. In the press molding method to which this invention is applied, it is a figure which shows the process of accommodating a to-be-molded glass raw material in a shaping | molding die. It is a figure which shows the process in the press zone of a press molding apparatus in the press molding method to which this invention is applied. It is a figure which shows the process for taking out a glass molded object from a shaping | molding die in the press molding method to which this invention is applied. It is a figure which shows the process for taking out a glass molded object from a shaping | molding die in the press molding method to which this invention is applied. It is a figure which shows the taking-out process of the press molded object using the adsorption | suction apparatus which concerns on other embodiment of this invention.

Explanation of symbols

G Glass molded body 10 Mold unit 12 Upper mold 12A Upper mold body 12B Upper mold sleeve 12C Release ring 12D Spring 12a Upper molding surface 14 Lower mold 14A Lower mold body 14B Lower mold sleeve 14a Lower molding surface 14b Molding peripheral surface 16 Cavity DESCRIPTION OF SYMBOLS 18 Ventilation path 18a Ventilation gap 18b Passage 18c Ventilation groove 22 Adsorption device 24 Adsorption pad 24a Adsorption hole 24b Collar part 26 Support body 26a Receiving part 32 Support stand 34 Adsorption conveyance apparatus 40 Glass carrying-in pad 42, 44 Press head

Claims (10)

In an adsorption device for adsorbing a molded body,
An adsorbing member having an adsorbing surface for adsorbing the molded body;
A support that supports the suction member so as to be movable in the vertical direction;
Suction means for sucking gas from the suction surface;
Elevating means for elevating and lowering the support;
An apparatus for adsorbing a molded body, comprising:   The outer diameter of the suction surface of the suction member is larger than the inner diameter of a cavity for molding the molded body, and the suction holes formed in the suction surface are smaller than the outer diameter of the molded body. The adsorbing device for the molded body described.   The outer diameter of the suction surface of the suction member is smaller than the inner diameter of a cavity for molding the molded body, and the suction holes formed in the suction surface are smaller than the outer diameter of the molded body. 2. The molded body adsorption apparatus according to 1.   A method for removing a molded body, wherein the molded body molded by the molding apparatus is taken out using the adsorption device according to any one of claims 1 to 3. A press-molded body molded by a press mold having a cavity surrounded by a molding surface of the upper and lower molds and a circumferential surface located on the outer peripheral side thereof is used using the molded body adsorption device according to claim 1 or 2. The method of taking out
After separating the molding surface of the upper mold from the press-molded body, the suction member closes the press-molding die, and further sucks the gas in the cavity to attract the press-molded body to the suction surface. A method for removing a press-molded body, wherein the press-molded body is removed from the press mold.   6. The method of taking out a press-formed body according to claim 5, wherein the press-formed body is adsorbed on an adsorption surface by sucking the gas in the cavity and floating the press-formed body in the cavity.   The method of taking out a press-molded body according to claim 5 or 6, wherein when the press-molded body is adsorbed by the adsorbing member, the adsorbing member moves up and down with respect to the support body.   The method of taking out the press-molded body according to any one of claims 4 to 7, wherein the press-molded body is taken out when the press-molded body is in a temperature range of Tg-50 ° C to Tg ° C. .   A method for producing a press-molded body, comprising: pressing a soft material to be molded to form a press-molded body, and then taking out the press-molded body by using the adsorption device according to claim 1.   A press molding die having a cavity surrounded by a molding surface of the upper and lower molds and a circumferential surface located on the outer peripheral side thereof is used to press a soft material to be molded to form a press molded body. A method for producing a press-molded body, comprising: taking out the press-molded body by the take-out method according to any one of claims 4 to 8 after separating the molding surface from the press-molded body.

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