JP4804280B2 - Mold press molding apparatus and method for manufacturing molded body - Google Patents

Description

  The present invention relates to a mold press molding apparatus capable of producing a molded body such as an optical element (for example, a glass lens) by press-molding a molding material such as a glass preform with a precision-processed mold, and a molded body It relates to a manufacturing method.

  In recent years, an optical glass material is accommodated in a mold that has been precisely machined to a predetermined surface accuracy, and the molded surface is ground by pressing it under heat and transferring the molded surface. There is known a method of manufacturing an optical element such as a glass lens having a high-precision optical functional surface that does not require post-processing such as polishing.

For example, Patent Document 1 discloses glass in which processing chambers such as a heating chamber, a press chamber, and a cooling chamber are arranged side by side in a circumferential direction, and molding molds containing molding materials are sequentially transferred in these processing chambers. An apparatus for manufacturing a molded body is disclosed.
In this manufacturing apparatus, each processing chamber is formed by being surrounded by a case in the furnace body, and a sample table is provided on a rotary table provided so as to be intermittently rotatable around a central rotary shaft. The glass molded body can be continuously formed by circulating the processing molds placed on the sample stage through the processing chambers as the rotary table is driven to rotate.

Japanese Patent Publication No. 7-29779

By the way, in the apparatus of Patent Document 1, it is possible to control the temperature management of each processing chamber independently and precisely, and it is possible to prevent temperature fluctuations accompanying the transfer of the mold, and In addition to this, if the molding material is displaced in the molding die due to vibration during transfer, the optical element to be molded becomes uneven, resulting in a defective shape as well as due to uneven thickness. Although the surface accuracy of the optical functional surface is deteriorated due to nonuniformity of the press load application, according to the apparatus of Patent Document 1, the mold can be smoothly transferred by the rotary table without causing vibration to the mold. it can.
As described above, the apparatus of Patent Document 1 has a very excellent function in manufacturing an optical element having a high-precision optical function surface.

However, in the apparatus of Patent Document 1, when an attempt is made to improve the productivity by simultaneously processing a plurality of molds in the same processing chamber, the arrangement position of the sample stage on which each mold is placed, It has been found that temperature differences may occur between the molds due to individual differences between the molds and the sample stage.
In particular, even if a plurality of molds are arranged in a state where the distance from the heating means is kept uniform, when the temperatures of the molds located at both ends of the array and the molds located inside the array are compared, The mold located inside tends to be hotter. This is thought to be due to the difference in the amount of heat energy received from adjacent molds and sample stands.

  Such a temperature difference has been conventionally overlooked without being regarded as a problem, but in the recent situation where the accuracy required for optical elements is becoming increasingly severe, the temperature generated between molds The difference led to the finding that it would adversely affect high precision molding.

  That is, if the molding conditions (particularly the heating temperature) for each mold are different, the required accuracy can be obtained even if each molding die contains the same glass material and tries to mold the same optical element. As it increases, it becomes impossible to stably mass-produce optical elements having a certain quality. In particular, when optical elements are molded with low-dispersion and high-refractive-index glass materials, the allowable range of press temperature is extremely narrow. It becomes impossible to obtain the molded product.

  For this reason, in order to stably perform high-precision molding, it is necessary to take measures to prevent the temperature difference between the molds from occurring, but in order to eliminate such a temperature difference between the molds. In addition, even if the set temperature of the heating means is simply adjusted, variations occur depending on the arrangement relationship and the number of the mold and the support bases that support the mold, and it is very difficult to eliminate the temperature difference. Further, if the heating means is installed in a one-to-one correspondence with the molding die or the support base, not only the entire apparatus is enlarged, but also a cost disadvantage is increased.

  Optical elements used in imaging devices such as digital cameras, optical pickup devices, and small-sized imaging devices for portable terminals have extremely high optical performance requirements, and it is expected that further improvements in performance will be required in the future. For this reason, in order to stably mold such an optical element with high precision using a precision mold press, temperature management in each processing step of the molding process, particularly when simultaneously processing a plurality of molding dies in the same processing chamber. Therefore, it is necessary to precisely perform soaking of the mold.

  The present invention has been made in view of the above circumstances, and in processing a plurality of molds each containing a molding material simultaneously to mold an optical element, the temperature of the mold in each processing step is accurately determined. It is an object of the present invention to provide a mold press molding apparatus and a method for manufacturing an optical element that can efficiently and stably manufacture a molded body such as a high-precision optical element.

Press-molding apparatus of the present invention for achieving the above object, a molding material contained in the mold, a mold press forming apparatus press-forming with the temperature controlled by heating each of the mold, said mold The mold includes a pair of upper mold and lower mold in which molding surfaces facing each other are formed, and a body mold that regulates the mutual position of the upper mold and the lower mold in the horizontal direction . Provided in at least one of the processing chambers, a plurality of processing chambers for performing each process including heating, pressing, and cooling, a transfer means for transferring a plurality of the molds to the respective processing chambers simultaneously. A heating means for simultaneously heating a plurality of the molds that are simultaneously transferred to the processing chamber in a state in which the molding material is accommodated, and the processing unit corresponding to the arrangement position of the molding molds in the processing chamber. It is attached to the processing chamber together with the heating means at an arbitrary position between the means and the mold, and the heat energy emitted from the heating means is partially irradiated to the mold. And a shielding means for shielding.

  According to the mold press molding apparatus of the present invention adopting such a configuration, it is difficult to control only by adjusting the output of the heating means by partially blocking the thermal energy irradiated to each mold. A high-precision molded product can be manufactured efficiently and stably by eliminating a temperature difference between the various molding dies and using a plurality of molding dies placed in an equivalent temperature environment.

The mold press molding apparatus of the present invention also includes a plurality of processing chambers for performing each process including heating, pressing, and cooling on the mold, and a plurality of the molds are simultaneously transferred to the processing chambers. by providing a transfer means for, in the processing chamber, and transported by a plurality molds simultaneously, one processing chamber are arranged a plurality of molds it is possible to simultaneously apply the same process, production efficiency Can be improved.

In the mold press molding apparatus of the present invention, as the shielding means, an insulating shielding member is attached close to the heating means, or the shielding means is provided on the heating means side. It can be set as the structure which has a property shielding member and the metal shielding member arrange | positioned at the said shaping | molding die side.
With such a configuration, it is possible to adjust the degree of the heat shielding effect while achieving insulation from the heating means. That is, the shielding means is basically composed of the insulating shielding member alone, and the shielding means is configured by stacking the metal shielding member on the insulating shielding member when the heat shielding effect is insufficient only with the insulating shielding member. Is preferred.

Further, the mold press molding apparatus of the present invention is provided so that the heating means can simultaneously heat three or more of the molding dies arranged in parallel with the heating means, and is positioned at both ends of the arrangement. The shielding means may be provided so that the thermal energy applied to the molds located inside the array is smaller than the thermal energy applied to the molds.
With such a configuration, the temperature rise of the molds located inside the array whose temperature tends to be relatively high is suppressed, and the temperature of the plurality of molds arranged in parallel with the heating means is equalized. It can be made.

A method of manufacturing a molded article of the present invention, the molding material contained in the mold, a process for producing a molded article by press molding with the temperature controlled by heating each of the mold, the mold The molding includes a pair of upper and lower molds on which molding surfaces facing each other are formed, and a barrel mold that regulates the mutual position of the upper mold and the lower mold in the horizontal direction, and the molding material is accommodated therein. Heating provided to at least one processing chamber among the processing chambers by transferring a plurality of the molding dies simultaneously to a plurality of processing chambers for performing respective processes including heating, pressing, and cooling on the mold. Means for simultaneously heating a plurality of the molds containing the molding material, and shielding means for partially blocking the heat energy emitted from the heating means from being applied to the mold. In the processing chamber Corresponding to the arrangement position of the molding die, the temperature of each of the molding dies is equalized by being placed in the processing chamber together with the heating means at an arbitrary position between the heating means and the molding die. This is a method of press-molding the molding material while controlling the temperature so that the temperature is reduced.

  According to the method for producing a molded body of the present invention, which has such a method, for a mold having a high temperature, the temperature difference between the molds is eliminated by partially blocking the irradiation of thermal energy from the heating means. It is possible to perform press molding on the plurality of molding dies under the same temperature condition by controlling the temperature so that the temperatures of the molding dies are equalized.

The method for producing a molded body of the present invention includes a heat treatment for heating the molding die by the heating means while simultaneously transferring a plurality of the molding dies, and a press treatment for pressing the molding material softened by heating. And a method of sequentially performing each process including a cooling process for cooling the mold.
With such a method, a plurality of molds can be simultaneously processed in the same processing chamber to improve productivity and stably perform high-precision molding.

  In the method for producing a molded body of the present invention, when controlling the temperature so that the temperatures of the molding dies are equalized, any one or more of the size, thickness, material, and fixing position of the shielding means is adjusted. Thus, the temperatures of the molds can be equalized. Then, when determining the arrangement of the shielding means, etc., the temperature difference of each of the molds heated by the heating means is measured in advance, and the temperature is relatively determined based on the measurement result. You may make it equalize the temperature of each said shaping | molding die by providing the said shielding means so that the heat energy irradiated to a high shaping | molding die may be reduced.

  As described above, according to the present invention, it is possible to eliminate a slight temperature difference between the molds, which is difficult to control only by adjusting the output of the heating means, and a plurality of parts placed in an equivalent temperature environment. With this molding die, a highly accurate molded product can be produced efficiently and stably.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic plan view showing an embodiment of a mold press molding apparatus (hereinafter simply referred to as “molding apparatus”) according to the present invention, and FIG. 2 is an apparatus corresponding to the AA cross section of FIG. It is explanatory drawing inside. FIG. 3 is an explanatory diagram of the inside of the apparatus corresponding to the BB cross section of FIG. 1, and the transfer direction of the mold M is indicated by an arrow in the drawing.

  The molding apparatus of the present embodiment is molded into a desired shape by press-molding a molding material P, such as a glass preform, contained in the molding die M while heating the molding die M and controlling the temperature. For obtaining molded articles such as optical elements.

  If the shaping | molding die M used by this embodiment can press-mold the shaping | molding raw material P in a desired shape, the specific structure will not be restrict | limited in particular. For example, it includes a pair of upper mold 10 and lower mold 20 on which molding surfaces facing each other are formed, and a barrel mold 30 that regulates the mutual position of the upper mold 10 and the lower mold 20 in the horizontal direction. A material in which the molding material P is press-molded between the upper die 10 slidably guided by the barrel die 30 so as to be relatively close to and away from the lower die 20 can be used.

  In addition, the molding apparatus according to the present embodiment includes a plurality of processing chambers for performing processing including heating, pressing, and cooling on the mold M, and a transfer for transferring a plurality of molding dies M to the processing chambers simultaneously. The press molding is performed by sequentially performing each process such as a heating process, a pressing process, and a cooling process while transferring the molding die M in which the molding material P is accommodated. be able to.

  Here, the molding apparatus shown in FIG. 1 is mainly formed of stainless steel or other heat-resistant metal. For example, the cylindrical upper and lower openings are sealed to form a non-oxidizing gas inside. A chamber 1 having an airtight structure that can be maintained in an atmosphere (inert gas atmosphere) is provided. In the chamber 1, there are provided an extraction / insertion chamber P1 and processing chambers P2 to P8 that are arranged at almost equal intervals along the circumferential direction.

  In the illustrated example, P1 is an extraction / insertion chamber. In this take-out / insertion chamber P1, the setting environment of the processing chambers P2 to P8 is not impaired, and the mold M that has been molded is taken out, and the mold that contains the molding material P that is newly used for molding. M is inserted.

P2 is a first heating chamber, P3 is a second heating chamber, and P4 is a third heating chamber (or a soaking chamber). These are also collectively referred to as a heating unit, and a heating treatment is performed on the mold M. P5 is a press room. In the press chamber P5, a pressing process is performed in which a pressing load is applied by a pressing means to the mold M that has a temperature suitable for press molding by the heating process in the heating unit.
P6 is a first annealing chamber, P7 is a second annealing chamber, and P8 is a quenching chamber. These are also collectively referred to as a cooling unit, and a cooling process is performed on the mold M after the press load is applied. The quenching chamber P8 is provided with a quenching mechanism using a cooling gas to form a molding material. It is preferable to cool the mold M until the molded body that has been formed into a desired shape by press-molding P reaches a temperature that does not hinder atmospheric release.
These processing chambers P2 to P8 are independently controlled to a temperature suitable for each processing, and are partitioned by shutters S1 to S6 in order to keep the temperature in each processing chamber at a predetermined temperature.

  In the illustrated example, a support table 3 that supports and transfers the mold M is attached to a turntable 2 that is connected to a rotation driving means that rotates in the direction of the arrow in FIG. The turntable 2 has a disk shape with a diameter smaller than the inner diameter of the chamber 1 and is rotatably attached to the chamber 1 so that the center of rotation coincides with the center of the chamber 1.

  Further, although not particularly shown, the rotary table 2 includes a control means having an index machine in the center, and the rotary table 2 repeats rotation and stop at regular intervals, and intermittently by a predetermined rotation angle. By rotating, the support base 3 that supports the mold M is moved between adjacent processing chambers. The fixed time at this time, that is, the time from when the support base 3 starts to move due to intermittent rotation of the turntable 2 until the next movement is started is the molding cycle time. It becomes.

In this embodiment, an example of a rotary transfer type molding apparatus is illustrated and described. However, the transfer means of the mold M can be configured to be connected to a known drive means mainly for linear operation. The specific configuration is not particularly limited. Further, the arrangement of the take-out / insertion chamber P1 and the processing chambers P2 to P8 is not limited to the illustrated example, and can be variously changed according to the configuration of the transfer means of the mold M.
Furthermore, in order to optimize each treatment of heating, pressing, and cooling according to the composition of the molding material P and the shape of the molded body such as the optical element to be obtained, for example, four heating chambers, There may be two press chambers or three slow cooling chambers. In order to improve production efficiency, the same number of heating chambers, press chambers, and slow cooling chambers may be provided side by side, and multiple types of press molding requiring different temperature conditions and different pressurization conditions may be performed simultaneously. it can.

In the example shown in the drawing, the support base 3 includes a cylindrical upright portion 3b that stands in the vertical direction and whose upper end side is a support portion 3b that supports the mold M. The four support bases 3 fixed to the common base 3 c are attached to the turntable 2 by fitting the base 3 c into the holes 2 a formed on the outer peripheral side of the turntable 2.
As described above, a plurality of (four in the illustrated example) support bases 3 are fixed to a common base 3c, and each processing chamber in which each of the heat treatment, the press treatment, and the cooling treatment is performed is provided. By making it possible to move as a unit, it is possible to transfer a plurality of molding dies M to each processing chamber at the same time, arrange a plurality of molding dies M in one processing chamber, and simultaneously perform the same processing, Production efficiency can be improved.

  The molding die M inserted into the apparatus from the take-out / insertion chamber P1 is supported by the support base 3 attached to the rotary table 2 and is always non-sticky in a state where the molding material (or molded body) P is accommodated. Although sequentially transferred to the processing chambers P2 to P8 that are set in an oxidizing gas atmosphere, for convenience, in the example shown in the drawing, the four molds M that are transferred at the same time, M1, Let M2, M3, and M4.

  In the illustrated example, each of the first heating chamber P2, the second heating chamber P3, the third heating chamber P4, the press chamber P5, the first annealing chamber P6, and the second annealing chamber P7 is a case. The case 7 is fixed to the chamber 1 by an appropriate means (not shown). 2, the bottom wall 7a of the case 7 is formed with a slit 7b extending in the circumferential direction that serves as a movement path of the support base 3 when the mold M is transferred. The support table 3 is inserted into each processing chamber.

  Here, FIG. 2 shows the inside of the first heating chamber P2 as a representative, but the second heating chamber P3, the third heating chamber P4, the first annealing chamber P6, and the second annealing chamber P7 are: A structure common to the first heating chamber P2 can be obtained only by changing the set temperature, the arrangement of the shielding means 5 described later, and the like. The press chamber P5 can also have a common structure with other processing chambers except that it includes a pressing means.

  In the example shown in the figure, heating means 8 is installed on the inner side surface of the case 7 surrounding the processing chambers P2 to P7 so as to face the transfer path of the mold M and to face each other. In addition, a reflector 9 that covers the inner surface of the case 7 is disposed in the case 7 so that the heat energy emitted from the heating means 8 is reflected and the heat energy can be efficiently applied to the mold M. Can be kept.

  The processing chambers P <b> 2 to P <b> 7 are maintained at their respective set temperatures by adjusting the output of the heating means 8. For example, a thermocouple is arranged at the tip of the support base 3, and the conductive wire is rotated by the turntable 2. The temperature of the tip of the support base 3, that is, the bottom of the mold M, is measured by guiding to the shaft, and the output of the heating means 8 installed in each processing chamber can be controlled based on the measurement result. .

The specific configuration of the heating unit 8 is not particularly limited as long as it can simultaneously heat a plurality of molds M transferred into the processing chamber. For example, resistance heating or the like can be arbitrarily used. In the case of resistance heating, as shown in FIG. 3 and FIG. 4, the opposing side surfaces in a state where the strip-like resistance heating heating elements 81 and 82 meander several times in the vertical direction along the inner side surface of the case 7. It is preferable to attach them substantially symmetrically to each other.
FIG. 4 is a schematic plan view of the inside of the first heating chamber P1 as viewed from above. In the figure, 8a is an electrode for applying a voltage to the resistance heating heating elements 81 and 82.

In the molding apparatus according to the present embodiment, the heating unit 8 and the shielding unit 5 that partially shields the thermal energy emitted from the heating unit 8 from being applied to the molding die M are also provided. The position where such a shielding means 5 is provided can be determined according to the temperature of the molding die M immediately before the pressing process is performed. In at least one processing chamber, the position between the heating means 8 and the molding die M can be determined. Can be arranged at any position.
For example, in the illustrated example, the insulating shielding plate 5a as the shielding means 5 and the metal shielding plate are disposed so that the thermal energy irradiation to the molds M2 and M3 located inside the traveling direction is partially blocked. At the same time, the insulating shielding plate 5a as the shielding means 5 is disposed so that the thermal energy irradiation to the mold M4 located at the end in the traveling direction is partially blocked.
As described above, the molding apparatus according to the present embodiment is attached to the processing chamber together with the heating unit 8 at an arbitrary position between the heating unit 8 and the molding die M in accordance with the arrangement position of the molding die M in the processing chamber. The shielding means 5 is arranged to partially shield the thermal energy emitted from the heating means 8 from being applied to the mold M.

In the illustrated example, the shielding means 5 may be provided in all of the first heating chamber P2, the second heating chamber P3, and the third heating chamber P4. A rapid heat treatment is performed on the mold M, and in such an initial stage of heating, the temperature of the mold M, the support table 3 and the processing chamber is not stable, and the support table 3 moves to the mold M. Since the influence of radiant heat transfer cannot be ignored, the effect of providing the shielding means 5 tends to be large. On the other hand, in the third heating chamber (soaking chamber) P4 in which the heat treatment has progressed, the support table 3 as well as the mold M is at a temperature near the press temperature, and the temperature in the processing chamber is also stabilized, so that the shielding is performed. The effect of providing the means 5 tends to be small.
Therefore, the shielding means 5 becomes more effective as the processing chamber in the initial stage of heating is provided, and in the illustrated example, it is preferable to provide at least the first heating chamber P2.

Here, since a high voltage is applied to the resistance heating heating elements 81 and 82, if a conductive member is attached in the vicinity of the resistance heating heating elements 81 and 82, the resistance heating heating elements 81 and 82 and In such a case, the member itself generates heat and the heat shielding effect cannot be obtained, or the adjacent resistance heating heating elements 81 and 82 are short-circuited to damage the heating means 8. Possible malfunction.
On the other hand, the metal material can enhance the heat shielding effect as compared with the insulating member. In particular, the silver-based metal material is excellent in heat reflectivity for reflecting the radiant heat from the heating element, and the plate thickness is reduced. Even if it is made thin, a sufficient heat shielding effect can be obtained.

Therefore, in this embodiment, in order to insulate from the heating means 8, the insulating shielding plate 5a is attached close to the heating means 8, and the metal shielding plate 5b having a high heat shielding effect is attached to the outside thereof. It is preferable to do so.
That is, the insulating shielding plate 5a and the metal shielding plate 5b may constitute the shielding means 5 alone as long as there is no problem due to contact with the heating means 8 or the like. The metal shielding plate 5b having a size that does not protrude from the insulating shielding plate 5a when the insulating shielding plate 5a alone is a basic configuration and the heat shielding effect is insufficient only by the insulating shielding plate 5a. It is preferable that the shielding means 5 is configured to overlap the insulating shielding plate 5a.

In this embodiment, as the insulating shielding plate 5a, a ceramic material such as an insulating shielding plate having heat resistance can be used, and the thickness thereof is about 0.5 to 2.0 mm. be able to. Further, as the metal shield 5b, a silver metal material such as a heat-resistant stainless steel material or aluminum material can be used, and the thickness thereof can be about 0.5 to 2.0 mm.
The members 5a and 5b constituting the shielding means 5 are, for example, a fixing tool such as a screw for fixing an insulator for supporting the heating means 8 when the heating means 8 is installed on the inner side surface of the case 7. It can be installed by using in common.

  The illustrated molding apparatus has the above-described configuration, and the temperature of the processing chambers P2 to P7 is maintained at the temperature set for each by adjusting the output of the heating means 8, but the production efficiency is improved. Therefore, when a plurality of molding dies M are simultaneously transferred to each processing chamber and a plurality of molding dies M are arranged in one processing chamber to simultaneously perform the same processing, the molding dies in the processing chambers Depending on the arrangement position of M, a temperature difference between the molds may occur.

Specifically, even if a plurality of molding dies M are arranged in a state where the distance from the heating means 8 is kept uniform, due to the difference in the amount of heat energy received from the adjacent molding dies M or the support 3, etc. There is a tendency that the molds located on the inner side are hotter than the molds located at both ends of the array.
Furthermore, the temperature in each processing chamber is also affected by the set temperature of the adjacent processing chamber, and if the adjacent processing chamber is set to a relatively high temperature, the temperature is high in the portion close to that processing chamber. Tend to be. On the contrary, if the temperature of the adjacent processing chamber is set to be relatively low, the temperature tends to be low in a portion near the processing chamber. Such a temperature gradient in the processing chamber is reflected in a temperature difference between the plurality of molds M that are simultaneously transferred between the processing chambers.

  According to this embodiment, the shielding means 5 that partially shields the heat energy from the heating means 8 is interposed, and any one or more of the size, thickness, material, and fixed position of the shielding means 5 is adjusted. Thus, for the mold M having a high temperature, the temperature difference between the molds is eliminated by partially blocking the irradiation of the heat energy from the heating means 8 so that the temperatures of the molds M are equalized. Thus, press molding can be performed on the molding material accommodated in the plurality of molding dies M under the same temperature condition.

  For example, when three or more molding dies M arranged in parallel with the heating means 8 are heated at the same time, the temperature of the molding dies M located inside the arrangement tends to be relatively high. If the shielding means 5 is provided so that the thermal energy irradiated to the mold M located inside the array is smaller than the thermal energy irradiated to the mold M positioned at both ends of the array. Good. The specific arrangement of the shielding means 5 is such that the temperature variation (temperature difference) of the mold M is measured in advance without the shielding means 5 being provided, and the temperature is relatively determined based on the measurement result. The heat energy irradiated to the high mold M can be reduced so that the temperatures of the molds M are equalized.

In the present embodiment, as the heating means 8, a plurality of (two pairs in the illustrated example) resistance heating heating elements 81a along the transfer direction of the mold M as shown in FIGS. , 81b, 82a, 82b can be provided. In this way, the temperature difference between the molds can be more reliably eliminated by uniquely controlling the outputs of the resistance heating elements 81a, 81b, 82a, 82b in combination with the shielding means 5, and the mold M It is possible to further equalize the temperature of each.
5 and 6 are explanatory views showing other examples of the heating means 8, and correspond to FIGS. 3 and 4 showing examples of the heating means described above, respectively.

As described above, the molding apparatus according to the present embodiment integrally fixes the heating unit 8 that simultaneously heats the plurality of molding dies M and the shielding unit 5 that partially blocks the irradiation of the thermal energy to the molding dies M. Therefore, even if it is a transfer-type molding apparatus that transfers the mold M, a constant heat treatment can be performed on the plurality of molds M that are sequentially transferred. Furthermore, since the mold M transferred, the support table 3 that supports the mold M, and the shielding means 5 are maintained at a predetermined distance, it is possible to prevent a trouble such that they interfere with each other.
Furthermore, according to the molding apparatus of the present embodiment, a plurality of molding dies M can be press-molded under the same temperature condition, so that a large number of optical elements of the same glass type can be obtained for each of the molding dies M. It is also possible to produce a large number of optical elements having different shapes at the same time if the same glass type is used.

  Next, the present invention will be described in more detail with reference to specific examples.

[Example 1]
First, except that the shielding means 5 is not arranged, the internal structure of the processing chambers P2 to P5 is fixed to a common base 3c in an existing molding apparatus that is the same as the example shown in FIGS. Each of the four support bases 3 is made to support the molding dies M1 to M4 containing the molding material P, and simultaneously to the first heating chamber P2, the second heating chamber P3, the soaking chamber P4, and the press chamber P5. Press molding was performed while sequentially transferring.
As the molding material P, optical glass (transition temperature: 500 ° C.) preformed into a biconvex curved surface shape was used.

At this time, when the temperature of each mold M1 to M4 immediately before pressing in the press chamber P5 was measured, the result shown in FIG. 7 was obtained. From this result, it was found that the maximum temperature difference between the molds M1 to M4 is 9 ° C., and the temperatures of M2, M3, and M4 are relatively high when the mold M1 is used as a reference.
Furthermore, when the manufacturing process was continued, press treatment and cooling treatment were performed, and press molded products were taken out from the respective molds M1 to M4 and observed. As a result, a large variation in the thickness was observed.

Next, based on the above measurement results, the shielding means 5 was fixedly arranged in the first heating chamber P2 as in the example shown in FIGS.
That is, for the molds M2 and M3, an insulating insulating plate 5a made of alumina and a metal shielding plate 5b made of stainless steel were mounted on the inside and the outside, respectively. At this time, the distance between the insulating shielding plate 5a and the metal shielding plate 5b was set to 0.1 mm. Further, since the temperature of the mold M4 is lower than that of the molds M2 and M3, an insulating insulating plate 5a made of alumina is used for the mold M4 so that the shielding effect on the mold M4 is relatively reduced. Arranged alone.

With such a configuration, when press molding was performed in the same manner as described above, the temperatures of the molding dies M1 to M4 immediately before pressing were as shown in FIG. 8, and the maximum temperature difference was 1.4 ° C. The temperature difference of the mold was equalized.
Further, the manufacturing process was continued, press treatment and cooling treatment were performed, and press molded products were taken out from the respective molds M1 to M4 and observed. As a result, the thickness of the optical element was within an allowable range. .

[Example 2]
In the existing molding apparatus in which the internal structure of the processing chambers P2 to P5 is the same as the example shown in FIGS. 5 and 6 except that the shielding means 5 is not disposed, press molding is performed in the same manner as in the first embodiment. Went. FIG. 9 shows the temperatures of the molds M1 to M4 immediately before pressing. From this result, it was found that the maximum temperature difference between the molds M1 to M4 is 9 ° C., and the temperatures of the molds M2 and M3 located inside the array are relatively high.
Further, when the manufacturing process was continued, press treatment and cooling treatment were performed, and press molded products were taken out from the respective molds and observed. As a result, a large variation in the thickness of the optical element was observed.

Next, based on the above measurement results, the shielding means 5 was fixedly arranged in the first heating chamber P2 as in the examples shown in FIGS.
That is, an insulating insulating plate 5a made of alumina and a metal shielding plate 5b made of stainless steel were mounted on the inside and outside of the molds M2 and M3, respectively. At this time, the distance between the insulating shielding plate 5a and the metal shielding plate 5b was set to 0.1 mm. At the same time, the outputs of the resistance heating heating elements 81a, 81b, 82a and 82b of the heating means 8 are controlled so that the mold M1 and the mold M4 have the same temperature.

When the press molding was performed in the same manner as described above, the temperatures of the molding dies M1 to M4 immediately before pressing were as shown in FIG. 10, and the maximum temperature difference was 0.3 ° C. The temperature difference of the mold was equalized.
Further, the manufacturing process was continued, press treatment and cooling treatment were performed, and press molded products were taken out from the respective molds M1 to M4 and observed. As a result, the thickness of the optical element was within an allowable range. .

[Example 3]
In another manufacturing apparatus in which the internal structure of the processing chambers P2 to P5 has the same configuration as that of the first embodiment, press molding was performed in the same manner as in the first embodiment. FIG. 11 shows the temperatures of the molds M1 to M4 immediately before pressing. As described above, the molds M1, M2, and M4 were almost the same as those in the first example, but only the mold M3 was slightly lower in temperature.
Therefore, the arrangement of the shielding means 5 is the same as in Example 1 except that the metal shielding plate 5b as the shielding means 5 for the mold M3 is omitted and only the insulating shielding plate 5a made of alumina is used.

  With such a configuration, when press molding was performed in the same manner as in Example 1, the temperatures of the molding dies M1 to M4 immediately before pressing were as shown in FIG. 12, and the maximum temperature difference was 0.9 ° C. The temperature difference of each mold was equalized.

  Although the present invention has been described with reference to the preferred embodiment, it is needless to say that the present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present invention. .

For example, in the above-described embodiment, the example in which the molding die M is mounted on each of the four support bases 3 and these are simultaneously heated has been described, but the support base 3 is not limited to four.

The present invention can also be applied to the case where the number of support bases 3 is two, three, or five or more, and the mold M supported by these support bases 3 is heated simultaneously.

  Further, in the above-described embodiment, the example in which the shielding means 5 is configured by superimposing the rectangular insulating shielding plate 5a and the metal shielding plate 5b has been shown. However, the shape is elliptical, circular, perforated, or the like. Can be set arbitrarily.

  The present invention is applied to a mold press molding apparatus for press molding a molded body such as an optical element (for example, a glass lens) and a method for manufacturing the molded body. In particular, when the mold containing the molding material is sequentially transferred to each processing chamber where processing such as heating, pressing, and cooling is performed and press molding is continuously performed, the temperature of the molding mold is made uniform. It is suitable for adjusting and manufacturing a highly accurate molded object stably.

It is a schematic plan view which shows embodiment of the mold press molding apparatus which concerns on this invention. It is explanatory drawing inside the apparatus equivalent to the AA cross section of FIG. It is explanatory drawing inside the apparatus equivalent to the BB cross section of FIG. It is the schematic plan view which looked at the inside of a processing chamber from the upper part. It is explanatory drawing which shows the other example of a heating means and a shielding means. It is explanatory drawing which shows the other example of a heating means and a shielding means. It is a graph which shows the temperature difference between the shaping | molding dies when not providing the shielding means in Example 1. It is a graph which shows the temperature difference between the shaping | molding dies at the time of providing the shielding means in Example 1. It is a graph which shows the temperature difference between the shaping | molding dies when not providing the shielding means in Example 2. It is a graph which shows the temperature difference between the shaping | molding dies at the time of providing the shielding means in Example 2. It is a graph which shows the temperature difference between shaping | molding dies when not providing the shielding means in Example 3. It is a graph which shows the temperature difference between the shaping | molding dies at the time of providing the shielding means in Example 3.

Explanation of symbols

3 Supporting base 5 Shielding means 5a Insulating shielding plate 5b Metal shielding plate 8 Heating means M Mold P Molding material P1 Extraction / insertion chamber P2 First heating chamber P3 Second heating chamber P4 Third heating chamber P5 Press chamber P6 First Slow cooling room P7 Second slow cooling room P8 Rapid cooling room

Claims (8)

A mold press molding apparatus that press-molds a molding material accommodated in a molding die while heating the molding die together with temperature control,
The mold includes a pair of upper mold and lower mold on which molding surfaces facing each other are formed, and a body mold for regulating the mutual position of the upper mold and the lower mold in the horizontal direction,
A plurality of processing chambers for performing each processing including heating, pressing, and cooling on the mold, and
Transfer means for transferring a plurality of the molds simultaneously to the processing chambers;
A heating means that is provided in at least one of the processing chambers and simultaneously heats the plurality of molding dies simultaneously transferred to the processing chamber in a state in which the molding material is accommodated;
Corresponding to the arrangement position of the molds in the processing chamber, the heating unit and the heating mold are attached to the arbitrary positions between the heating unit and the molding die and are disposed in the processing chamber, and are emitted from the heating unit. A mold press molding apparatus, comprising: shielding means for partially blocking the thermal energy irradiated to the mold. The mold press molding apparatus according to claim 1, wherein an insulating shielding member is attached as the shielding means in the vicinity of the heating means.   The mold press molding according to claim 1, wherein the shielding means includes an insulating shielding member disposed on the heating means side and a metal shielding member disposed on the mold side. apparatus. The heating means is provided so as to simultaneously heat the molds arranged in parallel with three or more parallel to the heating means,
The shielding means is provided so that the thermal energy applied to the molds located inside the array is smaller than the thermal energy applied to the molds located at both ends of the array. The mold press molding apparatus according to any one of claims 1 to 3 . A method for producing a molded body, in which a molding material housed in a molding die is press-molded while being heated and temperature controlled together with the molding die,
The mold includes a pair of upper mold and lower mold on which molding surfaces facing each other are formed, and a body mold for regulating the mutual position of the upper mold and the lower mold in the horizontal direction,
A plurality of the molds are simultaneously transferred to a plurality of processing chambers for performing each process including heating, pressing, and cooling on the mold containing the molding material,
While simultaneously heating the plurality of molds containing the molding material by a heating means provided in at least one of the process chambers,
Corresponding to the arrangement position of the molding die in the processing chamber, the heating unit and the molding die are arranged so that shielding means for partially blocking the heat energy emitted from the heating means from being irradiated on the molding die. By attaching and arranging in the processing chamber together with the heating means at any position between
A method for producing a molded body, wherein the molding material is press-molded while controlling the temperature so that the temperatures of the molding dies are equalized. A heating process for heating the molding mold by the heating means, a pressing process for pressing the molding material softened by heating, and a cooling process for cooling the molding mold. 6. The method for producing a molded body according to claim 5 , wherein each treatment is sequentially performed. The size of the shielding means, the thickness, material, and adjust any one or more fixed positions, any one of claims 5-6, characterized in that to equalize the temperature of each of said mold The manufacturing method of the molded object of description. The temperature difference of each of the molds heated by the heating means is measured in advance, and based on the measurement result, the shielding is performed so that the heat energy irradiated to the mold having a relatively high temperature is reduced. The method for producing a molded body according to any one of claims 5 to 7 , wherein the temperature of each of the molding dies is equalized by providing means.

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