WO2014181868A1

WO2014181868A1 - Apparatus and method for manufacturing glass compact

Info

Publication number: WO2014181868A1
Application number: PCT/JP2014/062478
Authority: WO
Inventors: 尚之繁野; 藤本　忠幸
Original assignee: Hoya株式会社
Priority date: 2013-05-10
Filing date: 2014-05-09
Publication date: 2014-11-13
Also published as: CN105164067B; JP2014218409A; CN105164067A; JP6047802B2

Abstract

An apparatus for manufacturing a glass compact in which multiple molding dies are pressed at one time by fewer actuators than there are molding dies, wherein the variation in the pressing pressures applied to the multiple molding dies is reduced. A press mechanism (70) comprises press heads (102), multiple shafts (100), actuators (80) a mobile plate (86), and coil springs (106). The press heads (102) are provided correspondingly with respect to a plurality of molding dies (52). The shafts (100) are respectively connected with the press heads (102), and extend to the outside after passing through an upper wall (2A) of a chassis (2). The actuators (80) are provided outside the chassis (1). The mobile plate (86) is disposed outside the chassis (2), and is pressed and moved toward the molding dies (52) by the actuators (80). The coil springs (106) are disposed outside the chassis (2), and can be compressed in the direction of movement of the mobile plate (86). The mobile plate (86) is pressed and moved toward the molding die (52), thereby pressing and moving the multiple shafts (100) and the press heads (102) via the coil springs (106).

Description

Glass molded body manufacturing apparatus and glass molded body manufacturing method

The present invention relates to a glass molded body manufacturing apparatus and a glass molded body manufacturing method, and in particular, a press mechanism that simultaneously presses a plurality of molding dies containing glass materials in a press chamber formed in a housing. The present invention relates to an apparatus for manufacturing a glass molded body provided with the above and a method for manufacturing a glass molded body using the apparatus.

Conventionally, for example, as described in Patent Document 1 (Japanese Patent Application Laid-Open No. 2008-56532), a plurality of support members on which a mold is placed are heated by a rotary table along a circumference. 2. Description of the Related Art An apparatus that forms glass by performing heating, pressing, and cooling (including slow cooling) processing in each processing section while sequentially circulating a section, a pressing section, and a slow cooling section is widely used. When manufacturing a small-diameter lens using such a glass molded body manufacturing apparatus, a plurality of molding dies are placed on each support member, and a plurality of molding dies are pressed at once to achieve production efficiency. Can be improved.

It is possible to increase production efficiency by pressing a plurality of molds at a time, but when pressing a plurality of molds in a limited space, it is necessary to reduce the pitch between the molds. In order to cope with this, it is conceivable to install an actuator for each of a plurality of molds. In such a case, there is a possibility that a required press pressure cannot be ensured with a small actuator. For this reason, in order to press a plurality of molds at a time, it is necessary to drive the press head with a smaller number of actuators than the molds.

Also, a difference occurs in the height of the upper surface of the mold due to a manufacturing error of the support member that supports the mold. Furthermore, a difference occurs in the height of the upper surface of the mold due to dimensional changes due to long-term use. For this reason, when a plurality of press heads are lowered all at once by a small number of actuators, a large pressure is applied to a mold with a high top surface, and a slight pressure is applied to a mold with a low top surface. There was a problem that variations occurred.

Therefore, for example, as shown in FIG. 4 of Patent Document 2 (Japanese Patent Laid-Open No. 9-239757), a compression spring is interposed between the actuator and the press head for pressing the mold in the housing. It is possible. In this way, by pressing the press head via the compression spring, the compression spring absorbs the difference in the height of the mold, so that variations in the press pressure can be reduced.

JP 2008-56532 A JP-A-9-239757

However, as shown in FIG. 4 of Patent Document 2, since this compression spring is provided in the casing, it is necessary to use a compression spring having a short height in order to be limited in space. If such a short compression spring is used, the ratio of the difference in the height of the mold relative to the total length is large, and the effect of the difference in the height of the upper surface of the mold is still exerted on the press pressure acting on each mold. End up. For this reason, even if a compression spring is interposed as shown in Patent Document 2, the difference in press pressure between the dies still remains.

The present invention has been made in view of the above problems, and the object thereof is to provide a plurality of molding dies in a glass molding manufacturing apparatus that presses a plurality of molding dies at once with a smaller number of actuators than the molding dies. It is an object of the present invention to provide a technique capable of producing a glass molded body with uniform molding accuracy with high production efficiency by reducing the variation in applied pressing pressure.

The apparatus for producing a glass molded body of the present invention is an apparatus for producing a glass molded body having a press mechanism for simultaneously pressing a plurality of molds containing glass materials in a press chamber formed in a housing. The press mechanism is provided corresponding to a plurality of molds, and is connected to a plurality of press heads for individually pressing the molds and the plurality of press heads, and penetrates the upper wall of the housing in parallel to each other. A plurality of shafts extending to the outside, an actuator provided outside the housing, a moving member disposed outside the housing and pressed and moved toward the mold by the actuator, and disposed outside the housing And an elastic member that is compressible in the moving direction of the moving member, and the moving member is pressed and moved toward the molding die by the actuator via the elastic body. Toward the number of shafts and the press head mold is pressed and moved.

Further, the method for producing a glass molded body of the present invention comprises a step of simultaneously pressing a plurality of molding molds containing glass materials by a press mechanism in a press chamber formed in the casing, A plurality of press heads provided corresponding to a plurality of molding dies, respectively connected to the plurality of press heads for individually pressing the molding dies, and extending to the outside through the upper wall of the housing in parallel to each other Shaft, an actuator provided outside the housing, a moving member disposed outside the housing and pressed and moved toward the mold by the actuator, and a moving member disposed outside the housing. Elastic member that is compressible in the direction, and in the press step, the moving member is pressed and moved toward the mold by the actuator, Through to press moves towards a plurality of shafts and the press head mold.

According to the present invention, since the elastic body is provided outside the housing, a longer elastic body can be used than when the elastic body is provided in the press chamber. By using such a long elastic body, the ratio of the difference in the height of the mold with respect to the length of the elastic body in the contracted state is reduced. Thereby, even if there exists a difference in the height of a shaping | molding die, the dispersion | variation in the press pressure added to each shaping | molding die can be suppressed small.

According to the present invention, in a glass molded body manufacturing apparatus that presses a plurality of molding dies at once with a small number of actuators, variation in press pressure applied to the plurality of molding dies can be further reduced.

It is a horizontal sectional view which shows the structure of the manufacturing apparatus of the glass forming body used by this embodiment. FIG. 2 is a cross-sectional view taken along the line AA in FIG. It is a vertical sectional view showing the configuration of the mold unit. It is a front view which shows the detailed structure of the press mechanism provided in the press chamber, and shows the state which is performing the press process. It is a side view which shows the detailed structure of the press mechanism provided in the press chamber, and shows the state which is performing the press process. It is a side view which shows the detailed structure of the press mechanism provided in the press chamber, and shows the state which is not performing the press process. It is a horizontal sectional view which shows the structure of the manufacturing apparatus provided with two press chambers. It is a figure which shows arrangement | positioning of the support part in the type | mold support stand which provided eight support parts. It is a vertical sectional view showing the composition of the modification of the type support member which incorporated the coil spring in the press mechanism.

Hereinafter, an embodiment of a manufacturing apparatus and a manufacturing method of a glass molded body of the present invention will be described in detail with reference to the drawings. In addition, in each embodiment, about the site | part which has a common structure and function, the same code | symbol is attached | subjected and description is abbreviate | omitted.
FIG. 1 is a horizontal sectional view showing a configuration of a glass molded body manufacturing apparatus used in the present embodiment, and FIG. 2 is a sectional view taken along line AA in FIG. As shown in FIG. 1, the glass molded body manufacturing apparatus 1 of the present embodiment includes an apparatus housing 2 formed in a bottomed cylindrical shape, a rotary table 4 provided in the apparatus housing 2, and a rotary table. 4 and an inner casing 6 having an arcuate horizontal cross section provided above 4. The device casing 2, the inner casing 6, and the turntable 4 are arranged concentrically.

The device casing 2 has a substantially circular upper lid 2A and a bottom plate 2B attached to the top and bottom, and the inside thereof is in a sealed state. The internal space of the apparatus housing 2 is an inert gas atmosphere. As the inert gas, nitrogen, argon, or the like is used, and the oxygen concentration is preferably 5 ppm or less. It should be noted that the oxidation of the mold unit 8 and the surface alteration of the glass material can be prevented by making the internal space an inert gas atmosphere in this way.

The upper lid 2A is formed with a loading / unloading port (not shown) through which the molding die 52 is supplied into the apparatus and the molding die 52 can be unloaded from the apparatus. 46 is formed. In the present embodiment, the carry-in / carry-out unit 46 is shown as an example having both the supply unit and the carry-out unit in the present invention. However, the carry-in unit (supply unit) and the carry-out unit (carry-out port) are provided separately. May be.

The rotary table 4 is rotated by, for example, a drive mechanism (not shown) such as a motor, and the mold unit 8 arranged on the rotary table 4 is conveyed on the same circle. On the rotary table 4, a number of mold units 8 (eight in the present embodiment) corresponding to the number of processing chambers are arranged at equal intervals. As will be described later, the mold unit 8 includes a mold support base (support member) 12 and a plurality of (four in this embodiment) molding dies 52 placed on the mold support base 12. .

The mold unit 8 arranged on the turntable 4 is intermittently transferred to each processing chamber in the inner casing 6 as the turntable 4 rotates. In the present embodiment, the rotary table 4 conveys the mold unit 8 along the circumference of a predetermined radius by intermittently rotating the drive mechanism by 45 degrees every predetermined time. Further, the rotary table 4 stops for a predetermined stop time set in advance during each rotation operation. The stop time of the rotary table 4 is determined to be longer than the time required for the press process in the press chamber 26 described later.

The inner casing 6 is concentrically coaxial with the apparatus housing 2 and extends in an arc shape over an angular range of about 270 degrees in the horizontal direction. The inner casing 6 is located radially outside the inner wall 6A and has an angular range of about 270 degrees in the horizontal direction. An outer wall 6B extending in a circular arc shape, a ceiling 6C that closes between the inner wall 6A and the upper part of the outer wall 6B, and a bottom 6D that closes between the inner wall 6A and the lower part of the outer wall 6B. The inner wall 6A, the outer wall 6B, the ceiling portion 6C, and the bottom portion 6D form a processing space having an arc-shaped horizontal cross section in the inner casing 6. An arc-shaped slit 6E is formed in the bottom 6D of the inner casing 6 along the conveyance path of the mold unit 8.

The processing space of the inner casing 6 is divided into six chambers within an angle range of 45 degrees in the rotation direction of the turntable 4. These six chambers are arranged along the conveyance path of the mold unit 8 in the first heating chamber 20, the second heating chamber 22, the soaking chamber 24, the press chamber 26, the first annealing chamber 28, and the second annealing chamber. They are arranged in the order of 30.

The

heating chambers

20 and 22 are processing units for rapidly heating the mold 52 and the glass material 60 of the mold unit 8 charged in the apparatus to a temperature suitable for press molding at a temperature close to normal temperature. In this embodiment, the two heating chambers, the first heating chamber 20 and the second heating chamber 22, are provided, and the mold unit 8 is heated in stages, but the number of chambers is set according to the processing time and the target temperature. It may be increased or decreased.

The soaking chamber 24 is a processing unit for soaking the mold 52 and the glass material 60 by heating the mold unit 8 to a temperature suitable for press molding at a temperature for a predetermined time. The temperature suitable for press molding varies depending on the glass glass type and the shape and volume of the molded body, but is generally a temperature at which the glass material has a viscosity of 10 ⁶ to 10 ⁹ dPa · s, and the glass yield point temperature (Ts ) Is preferably in the vicinity.

A press mechanism 70 is provided above the press chamber 26, and the press chamber 26 is heated to a predetermined temperature and softened by applying a load to the plurality of molds 52 at once by the press mechanism 70. It is a processing unit that deforms the glass material and transfers the shape of the molding surface of the mold to form a glass molded body. The detailed configuration of the press mechanism 70 will be described later.

The

slow cooling chambers

28 and 30 are processing units that gradually cool the glass molded body formed in the press chamber 26 at a predetermined cooling rate. In this embodiment, two slow cooling chambers, the first slow cooling chamber 28 and the second slow cooling chamber 30, are provided, and the mold unit 8 is gradually cooled, but the number of chambers is increased or decreased as necessary. May be.
A shutter (not shown) is provided between the circumferential end of the inner casing 6 and each chamber to partition adjacent processing chambers.

Heaters

32, 34, respectively, are provided on both sides of the transport path of the first heating chamber 20, the second heating chamber 22, the soaking chamber 24, the press chamber 26, the first annealing chamber 28, and the second annealing chamber 30, respectively. 36, 38, 40, and 42 are provided. These

heaters

32, 34, 36, 38, 40, 42 are respectively a first heating chamber 20, a second heating chamber 22, a soaking chamber 24, a press chamber 26, a first annealing chamber 28, and a second annealing chamber. The inside 30 is heated to a predetermined temperature.

Further, as shown only in FIG. 2, the press chamber 26 is provided with a reflector 38A along the inner wall 6A and the outer wall 6B. The reflector 38A reflects the heat energy radiated from the heater 38 and prevents the heat from being released to the outside of the heater. Thereby, heat energy can be intensively guided to the mold and the mold can be efficiently heated. The reflector includes a first heating chamber 20, a second heating chamber 22, a soaking chamber 24, a first annealing chamber 28, and a second annealing chamber 30 provided with

heaters

32, 34, 36, 40, and 42. It is also installed inside.

FIG. 3 is a vertical sectional view showing the configuration of the mold unit 8. As shown in FIG. 3, the mold unit 8 includes a mold support 12 and a plurality of (four in this embodiment) molds 52 placed on the mold support 12. As the material of the mold 52, silicon carbide, cemented carbide, silicon nitride, or the like is used. The mold support 12 includes a base portion 12A and a plurality of (four in the present embodiment) columnar support portions 12B provided in a row on the base portion 12A. In the present embodiment, the mold unit 8 is disposed on the rotary table 4 so that the direction in which the support portions 12B of the mold support 12 are aligned matches the moving direction of the mold unit 8 by the rotary table 4.

Each mold 52 is placed on each support portion 12B of the mold support 12. The molding die 52 has an upper die 54 and a lower die 56 having molding surfaces formed in accordance with the shape of the glass molded body to be manufactured, and a cylinder that regulates the mutual position of the upper die 54 and the lower die 56 in the radial direction. And a mold 58. A release film for preventing fusion with glass is formed on the molding surfaces of the upper mold 54 and the lower mold 56. The glass material 60 is disposed in a state of being sandwiched between the upper mold 54 and the lower mold 56. In a state where the glass material 60 is heated to the glass yield point temperature or higher, by pressing the upper and

lower molds

54 and 56 in a relatively close direction, the shape of the molding surface is transferred to the glass material, and a glass molded body having a desired shape (Optical element) can be press-molded.

4 to 6 show a detailed configuration of the press chamber and the press mechanism provided above the press chamber, and FIG. 4 is a partial cross-sectional view when seen in a cross-section along the conveying direction of the mold unit 8. 6 and 6 are partial cross-sectional views when viewed in cross-section in a direction orthogonal to the transport direction. 4 and 5 show a state where the press process is being performed, and FIG. 6 shows a state where the press process is not being performed.
As shown in FIG. 4, the press mechanism 70 includes a plurality of press heads 102 provided corresponding to the respective molds 52, a shaft 100 connected to the press head 102 and extending in the vertical direction, and the housing 2. A support mechanism 72 provided above the actuator, an actuator 80 fixed to the upper portion of the support mechanism 72, a moving plate 86 movable in the vertical direction by the actuator 80, and a coil spring provided corresponding to each shaft 100. 106.

The support mechanism 72 includes a plurality of legs 74 standing on the upper surface of the upper lid 2 </ b> A of the housing 2, and a support plate 76 that is held by the plurality of legs 74 at a distance from the upper lid 2 </ b> A of the housing 2. With. Two actuators 80 are fixed to the upper part of the support plate 76 of the support mechanism 72. An opening is formed in the support plate 76, and the piston rod 82 of the actuator 80 extends downward through this opening. The plurality of leg portions 74 are provided at positions spaced apart from the centers of the planar positions of the plurality of rods 88 at equal intervals.

One actuator 80 is provided on each side of the plurality of molds 52, and each actuator 80 can advance and retract the piston rod 82 in the vertical direction in synchronization. The tip of the piston rod 82 of each actuator 80 is connected to the moving plate 86. The connection positions are aligned in the direction perpendicular to the transport direction, and are positioned at the center of the plurality of shafts 100 in the direction in which the plurality of shafts 100 are aligned.

In a configuration in which one press head is provided for each press head, a small actuator needs to be used when the distance between the press heads is about 25 mm or less, such as when many small-diameter lenses are manufactured. . However, such a small actuator often cannot obtain a pressing force necessary for molding a lens. For this reason, in this embodiment, it is set as the structure which press-moves the four press heads 102 with the two actuators 80 with the physique which can obtain a desired pressing force. In the present embodiment, the four press heads 102 are pressed and moved by the two actuators 80, but the number of actuators and the number of press heads are not limited as long as the number of actuators is smaller than the number of press heads. In other words, the glass molded body manufacturing apparatus 1 according to the present embodiment has a smaller number of actuators 80 (including a single unit) than the total number of the plurality of press heads 102.

The moving plate 86 is movable in the vertical direction while being kept horizontal by the guide mechanism 81. A linear bushing 84 is erected on the upper surface of the moving plate 86. The tip of the piston rod 82 of the actuator 80 passes through the linear bush 84 and is fixed to the lower surface of the moving plate 86 in a state of penetrating the moving plate 86. As described above, since the piston rod 82 passes through the linear bushing 84, the moving plate 86 and the piston rod 82 of the actuator 80 are maintained in the vertical state.

The guide mechanism 81 includes a plurality of rods 88 extending downward from the lower surface of the support plate 76 of the support mechanism 72, and a plurality of linear bushes 92 movable along the plurality of rods 88. The upper ends of the plurality of rods 88 are fixed to the lower surface of the support plate 76 of the support mechanism 72 by the shaft holder 90.

The moving plate 86 has openings at four corners, and each of the plurality of rods 88 passes through the opening at each corner of the moving plate 86. That is, the plurality of rods 88 are provided outside the position where the shaft 100 of the moving plate 86 penetrates, and at a position spaced apart from the center of the position where the plurality of shafts 100 penetrate. Further, the piston rods 82 of the two actuators 80 are connected at a position spaced apart from the center of the position through which the plurality of shafts 100 of the moving plate 86 penetrate.

The linear bush 92 is fixed to the lower surface of the moving plate 86, and a corresponding rod 88 is inserted through each linear bush 92. Thereby, since the four corners of the moving plate 86 are moved along the rod 88 by the plurality of linear bushes 92, the moving plate 86 can be moved up and down while being kept in a horizontal state.

An opening is formed in the upper portion of the press chamber 26 of the housing 2, and the housing lid member 110 is attached to the opening without any gap. A plurality of through holes penetrating in the vertical direction are formed in the housing lid member 110 at positions corresponding to the plurality of shafts 100. A heat ablation member 116 made of a heat-reflective material is attached to the lower surface of the case lid member 110 along the lower surface.

Further, an opening is formed in the upper part of the press chamber 26 of the ceiling portion 6C of the inner casing 6, and a casing lid member 119 is attached to this opening. The casing lid member 119 is formed with through holes extending in the vertical direction at positions corresponding to the plurality of shafts 100.

Each of the plurality of shafts 100 extends in the vertical direction through the moving plate 86, the casing lid member 110, and the casing lid member 119. Nuts 104 are respectively fixed above the moving plates 86 of the plurality of shafts 100.

A locking portion 101 that protrudes toward the outer periphery is formed at a position above the housing lid 110 of the shaft 100. A coil spring 106 is disposed between the locking portion 101 and the moving plate 86. The coil spring 106 is externally mounted on the shaft 100. Thus, since the coil spring 106 is provided outside the housing 2, a coil spring 106 having a desired length can be used.

The press heads 102 are respectively provided at the lower ends of the plurality of shafts 100, and these press heads 102 press the molding die 52 as described later.

Oil seals 112 are respectively provided in the through holes formed in the casing lid member 110. The oil seal 112 seals the space between the through hole and the shaft 100, and the inside of the housing 2 can be maintained in an inert gas atmosphere. In addition, linear bushings 114 are provided in the through holes formed in the case lid member 110, respectively. The shaft 100 is guided toward the mold 52 by the linear bush 114.

Hereinafter, a method of manufacturing a glass molded body by the glass molded body manufacturing apparatus 1 of the present embodiment will be described. In the following description, a method of manufacturing a glass molded body will be described by paying attention to one mold unit 8, but in the glass molded body manufacturing apparatus 1 of the present embodiment, depending on the number of processing chambers. A plurality of mold units 8 are arranged on the rotary table 4 in an equiangular range of 45 degrees. The plurality of mold units 8 are continuously transported along the transport path by the rotary table 4, and processes such as heat treatment, press processing, and slow cooling processing are performed in parallel in each processing chamber.

First, when the rotary table 4 rotates and the mold unit 8 that accommodates the glass molded body for which the molding process has been completed reaches the carry-in / carry-out unit 46, the mold unit 8 is lifted by the carry-in / carry-out mechanism, From the outlet, the four molding dies 52 for which the molding process has been completed are simultaneously carried out of the apparatus housing 2. Then, these molds 52 are held by a robot hand (not shown) and removed from the support part 12B of the mold support 12. Thereafter, the molds 52 loaded with the new glass material 60 are placed on the support portions 12B of the mold support base 12, respectively.

When a preset stop time (hereinafter referred to as a tact time) of the rotary table 4 has elapsed since the completion of the previous rotation operation, the shutter provided between the circumferential end of the inner casing 6 and each chamber is opened. Thus, the rotary table 4 rotates 45 degrees counterclockwise in plan view. As a result, the mold 52 is conveyed into the first heating chamber 20 while being held by the mold support 12. At this time, the support portion 12B of the mold support 12 passes through the slit 6E provided at the bottom of the inner casing 6, so that the support portion 12B and the inner casing 6 do not interfere with each other.

When the mold unit 8 is conveyed to the first heating chamber 20, a first heating step for heating the mold unit 8 is performed. The inside of the first heating chamber 20 is maintained at a temperature equal to or higher than the glass yield point temperature (Ts) by the heaters 32 provided on both sides of the transport path. Then, the mold unit 8 conveyed to the first heating chamber 20 is heated by the heater 32.

When a preset tact time elapses from the previous rotation of the turntable 4, the shutter provided between the circumferential end of the inner casing 6 and each chamber is opened, and the turntable 4 is turned counterclockwise in plan view. Rotate 45 degrees. Thereby, the mold unit 8 is conveyed into the second heating chamber 22.

When the mold unit 8 is conveyed to the second heating chamber 22, a second heating step is performed in which the mold 52 of the mold unit 8 is heated to about the glass yield point temperature. The inside of the second heating chamber 22 is maintained at a temperature equal to or higher than the glass yield point temperature by the heater 34. Thereby, it heats until the glass material 60 in the metal mold unit 8 conveyed in the 2nd heating chamber 22 reaches about a glass yield point temperature.

When a preset tact time elapses from the previous rotation of the turntable 4, the shutter provided between the circumferential end of the inner casing 6 and each chamber is opened, and the turntable 4 is turned counterclockwise in plan view. Rotate 45 degrees. As a result, the mold unit 8 is transferred into the soaking chamber 24.

When the molding die 52 is conveyed to the soaking chamber 24, a soaking step for soaking the molding material 52 and the glass material 60 accommodated therein is performed. The inside of the soaking chamber 24 is maintained at the glass yield point temperature by the heater 36. Thereby, the shaping | molding die 52 conveyed to the soaking | uniform-heating chamber 24 and the glass material 60 in the shaping | molding die 52 are soaked at glass yield point temperature.

When a preset tact time elapses from the previous rotation of the turntable 4, the shutter provided between the circumferential end of the inner casing 6 and each chamber is opened, and the turntable 4 is turned counterclockwise in plan view. Rotate 45 degrees. Thereby, the mold unit 8 is conveyed into the press chamber 26.

When the mold unit 8 is conveyed to the press chamber 26, a press step is performed. In the pressing step, the glass unit is press-molded by simultaneously pressing the plurality of molds 52 of the mold unit 8 by the press mechanism 70 while heating the mold unit 8 by the heater 38 so as to maintain the glass yield point temperature. . Hereinafter, the press process for pressing the plurality of molds 52 by the press mechanism 70 will be described in detail.

As shown in FIG. 6, at the start of the press process, the piston rod 82 of the actuator 80 is in a retracted state. In this state, the coil spring 106 has a natural length or a length slightly compressed from the natural length. Each shaft 100 is held in a state where there is a gap between the press head 102 and the molding die 52 by the nut 104 attached to the upper part of the shaft 100 engaging the upper surface of the moving plate 86. .

When the press process is started, the actuator 80 first lowers the piston rod 82 downward. As described above, the moving plate 86 is movable in the vertical direction while being kept horizontal by the guide mechanism 81. For this reason, when the actuator 80 lowers the piston rod 82, the moving plate 86 is moved downward while being kept horizontal.

When the moving plate 86 is moved downward, the lower surface of the moving plate 86 contacts the upper portion of the coil spring 106 or compresses the coil spring 106. Further, the lower portion of the coil spring 106 is in contact with the locking portion 101 of the shaft 100. For this reason, when the moving plate 86 descends, the shaft 100 is pressed and moved downward via the coil spring 106. As a result, the press head 102 provided at the lower end of the shaft 100 contacts the upper surface of the mold 52. At this time, each shaft 100 is reliably guided toward the corresponding mold 52 by the linear bush 114 provided on the housing lid member 110.

The actuator 80 extends the piston rod 82 downward until the coil spring 106 is contracted to a predetermined length even after the press head 102 contacts the upper surface of the mold 52. As the coil spring 106 contracts in this way, a pressing load is applied to each mold 52. The length of the coil spring 106 in the contracted state is determined so that the restoring force of the coil spring 106 is equal to the press load to be applied to the mold 52. The press load (thrust) is set within a range of 10 to 500 kgf based on the material of the glass material.

Then, the coil spring 106 is contracted as described above and held for a predetermined time (for example, several tens of seconds to several minutes). Thereby, a molding surface shape is transcribe | transferred to the glass material accommodated in the shaping | molding die 52, and it can press-mold to the glass molded object (optical element) of a desired shape.

At this time, there is a variation in the height of the support portion 12B of the mold support 12 and there may be an error in the height of the upper surfaces of the plurality of molds 52. Thus, even if there is an error in the height of the upper surfaces of the plurality of molds 52, the coil spring 106 absorbs the error in the upper surface height, so that all the molds 52 can be pressed. However, although the coil spring 106 can absorb the error in the height of the upper surface of the mold 52 as described above, the difference in the length of the coil spring 106 in the contracted state is caused by the error in the upper surface height. Thus, if there is a difference in the length of the coil spring 106 in the contracted state, a difference also occurs in the press load to the mold 52.

In contrast, in the present embodiment, since the coil spring 106 is provided outside the housing 2, a coil spring having a long overall length can be used as the coil spring 106. By using a coil spring having a long overall length as the coil spring 106 in this way, the ratio of the difference in height of the mold 52 with respect to the length of the coil spring 106 in the contracted state is reduced. Thereby, the difference of the press load added to each shaping | molding die 52 can be restrained small to such an extent that there is no substantial influence.

Then, after the press process is finished, the actuator 80 retracts the piston rod 82. By moving the piston rod 82 backward, the moving plate 86 rises. Thereby, the coil spring 106 is again extended to the natural length, and the press load applied to the mold 52 is unloaded. Furthermore, when the actuator 80 retracts the piston rod 82 and raises the moving plate 86, the nut 104 attached to the upper part of the shaft 100 comes into contact with the upper surface of the moving plate 86 and raises the shaft 100. As a result, the press head 102 and the mold 52 are separated from each other. The press process is completed by the above steps.

When the press step is completed and the tact time has elapsed from the previous rotation of the turntable 4, the shutter provided between the circumferential end of the inner casing 6 and each chamber is opened, and the turntable 4 is viewed in plan view. Rotate 45 degrees counterclockwise. Thereby, the mold 52 of the mold unit 8 is conveyed into the first slow cooling chamber 28.

In the first slow cooling chamber 28, a first slow cooling step for slowly cooling the mold 52 is performed while adjusting the temperature of the mold 52 with the heater 40. It is preferable to appropriately set the cooling rate for the time in the range of 10 to 100 ° C./min.

When the first slow cooling step is completed and a preset tact time has elapsed since the previous rotation, the shutter provided between the circumferential end of the inner casing 6 and each chamber is opened, and the rotary table 4 rotates 45 degrees counterclockwise in plan view. Thereby, the mold 52 of the mold unit 8 is conveyed into the second slow cooling chamber 30.

In the second slow cooling chamber 30, a second slow cooling step for slowly cooling the mold 52 is performed while adjusting the temperature of the mold 52 by the heater 42. It is preferable to appropriately set the cooling rate for the time in the range of 10 to 100 ° C./min.

When the tact time elapses from the previous rotation of the rotary table 4, the shutter provided between the circumferential end of the inner casing 6 and each chamber is opened, and the rotary table 4 rotates 45 degrees counterclockwise in plan view. . Thereby, the mold 52 of the mold unit 8 is conveyed from the second slow cooling chamber 30 to the rapid cooling unit 44.

When the mold 52 is conveyed to the rapid cooling section 44, a rapid cooling step is performed. The quenching section 44 is not provided with a heater and has a temperature similar to that around the apparatus. For this reason, the glass molded body inside the mold unit 8 and the mold 52 is rapidly cooled. The cooling rate at this time is faster than the cooling rate in the slow cooling step, and is preferably set appropriately within a range of, for example, 30 to 300 ° C./min. Moreover, you may spray cooling gas toward the die unit 8 as needed.

Further, when a preset tact time elapses from the previous rotation of the rotary table 4, the rotary table 4 rotates 45 degrees and the mold unit 8 is transferred to the loading / unloading unit 46. When the mold unit 8 that accommodates the glass molded body that has undergone the molding process reaches the carry-in / carry-out unit 46, the mold unit 8 is raised by the lifting mechanism, and the mold 52 that has undergone the molding process from the carry-in / carry-out port. Are simultaneously carried out of the apparatus housing 2.

The molding die 52 carried out to the outside is disassembled, a glass molded body that has been molded is taken out, a new glass material is supplied, and then placed again on the support portion 12B of the mold support base 12.
Through the above steps, the glass molded body can be continuously produced by the production apparatus 1.

The inventors actually manufacture a glass molded body according to the manufacturing apparatus 1 of the present embodiment, which can reduce the difference in pressing force in the pressing process and can improve the quality of the glass molded body. Was confirmed. Examples of the present invention will be described below.

In this example, a biconvex lens having a diameter of 5 mm was molded. As a glass material, fluorophosphate glass (glass transition temperature 384 ° C., yield point 427 ° C.) is preformed into a biconvex curved shape to form a glass preform, and a carbon film is formed on the surface of the glass preform. What was done was used. The inside of the housing 2 of the molding apparatus 1 was preliminarily replaced with a nitrogen atmosphere. As the mold 52, an upper mold, a lower mold, and a body mold made of silicon silicon were used, and a carbon-based release film was provided on the molding surface in advance.

As the mold support base 12, a mold support base having four support portions erected on a straight line at a regular interval (21 mm pitch) on a disk-shaped base portion, and a molding die in which a glass material is accommodated in each support portion 12B. 52 was mounted.

As the coil spring 106 of the press mechanism 70, a coil spring having a free length of 100 mm and a spring constant of about 50 N / mm was used. For the actuator 80 that drives the press head 102 up and down, two pneumatic cylinders having a maximum thrust of about 250 kgf per unit were used.

The mold unit 8 is taken out from the insertion / insertion chamber and inserted into the molding apparatus and placed on the rotary table 4, and the mold unit 8 is moved to the first heating chamber 20 and the second heating chamber while the rotary table 4 is rotated intermittently. 22, soaking chamber 24, press chamber 26, first annealing chamber 28, second annealing chamber 30, and quenching chamber 44 were sequentially transferred to perform press molding. The time (cycle time) from the start of processing in one processing chamber to the start of processing in the next processing chamber is 75 seconds. The mold unit 8 is carried into and out of the molding apparatus 1 every cycle time, and continuously. Molding was performed. The press temperature in the press chamber 26 was about 450 ° C., and the press load was about 80 kgf.

In the pressing step, the actuator 80 (pneumatic cylinder) was driven to lower the moving plate 86, thereby lowering the four shafts 100 having the press heads 102 on the respective lower end sides.

After the pressing surface of each press head 102 abuts the corresponding forming die 52 (upper die), the press head 102 is further lowered until the upper surface of the upper die and the upper surface of the body die are flush with each other, The glass material was press-molded by pressing it with the upper mold and the lower mold. At this time, when the moving plate 86 is pushed by the cylinder, the coil spring 106 locked to the locking portion 101 of the shaft 100 is contracted, and the forming die 52 is pressed via the shaft 100 by the restoring force of the coil spring 106. It was.

The mold unit 8 that has finished the pressing step is cooled at a cooling rate of about 70 ° C./min in the first and

second annealing chambers

28 and 30 and gradually until the glass molded body is below the glass transition point. Chilled.
Next, a cooling gas (N ₂ ) was blown onto the mold 52 in the quenching chamber 44 to cool the mold 52 and the glass molded body inside the mold 52, and the temperature was lowered to 200 ° C. or lower.
Such a series of manufacturing processes was repeated to obtain 120 glass molded bodies (lenses).

Then, when a quality inspection was performed on each glass molded body, the non-defective product ratio satisfying the standard was 97.5% in any inspection items such as thickness accuracy, shape accuracy, and eccentricity accuracy. From this, according to the manufacturing apparatus of the glass molded object of this embodiment, since press pressure can be equalized, it has confirmed that a good-quality glass molded object can be manufactured.

According to the present embodiment, since the coil spring 106 is provided outside the housing 2, a longer one can be used as the coil spring 106 than when the coil spring is provided in the housing. For this reason, by using the long coil spring 106, the ratio of the height difference (variation) of the support portion 12B of the mold support base 12 and the mold 52 to the entire length of the coil spring 106 is reduced. Thereby, even if there exists a difference in the height of the shaping | molding die 52, the dispersion | variation in the press pressure applied to each shaping | molding die 52 can be suppressed small.

Further, since the glass molded body manufacturing apparatus 1 includes the guide mechanism 81 that guides the moving plate 86 in the vertical direction while keeping the moving plate 86 horizontal, the coil spring 106 can be pressed evenly.

Moreover, since the linear bushing 114 is provided in the case lid member 110, the shaft 100 can be lowered toward the corresponding mold 52 even when the length of the shaft 100 is long.

In the present embodiment, the first heating chamber 20, the second heating chamber 22, the soaking chamber 24, the press chamber 26, the first annealing chamber 28, and the second annealing chamber 30 are formed in the inner casing 6. Although the manufacturing apparatus 1 has been described, the present invention can also be applied to a manufacturing apparatus having a plurality of press chambers.

FIG. 7 is a horizontal sectional view showing a configuration of a manufacturing apparatus 150 having two press chambers. As shown in FIG. 10, in the manufacturing apparatus 150 shown in FIG. 10, a heating chamber 120, a first soaking chamber 122, a first press chamber 124, a first annealing chamber 126, and a second soaking chamber are provided in the inner casing 6. A chamber 128, a second press chamber 130, and a second slow cooling chamber 132 are provided. The heating chamber 120, the first soaking chamber 122, the first press chamber 124, the first annealing chamber 126, the second soaking chamber 128, the second pressing chamber 130, and the second annealing chamber 132 are respectively

Heaters

134, 136, 138, 140, 142, 144, and 146 are provided.

In the manufacturing apparatus having two press chambers as described above, if the press mechanism 70 described with reference to FIGS. 4 and 5 is used as the press mechanism provided in the first press chamber 124 and the second press chamber 130. Good.

Further, in the present embodiment, a case has been described in which a mold support base having four support portions in one row is used, and four molding dies 52 are pressed at a time, but the present invention is not limited to this. For example, FIG. 8 is a diagram illustrating the arrangement of the support portions in the mold support base 200 provided with eight support portions 202. In the embodiment shown in FIG. 8, the support portions 202 are provided in two rows, and four support portions 202 are provided in each row. In the present embodiment, the extending direction of each row coincides with the conveyance direction of the rotary table 4.

In such an embodiment, it is preferable that P1 ≦ P2 where P1 is the pitch of the support portions 202 in the transport direction and P2 is the pitch of the support portions 202 in the direction orthogonal to the transport direction. Even if it is arranged at such a narrow pitch, a plurality of molds can be press-molded with a uniform load, so that a high-quality glass molded body can be produced with high production efficiency.

In the present invention, the coil spring 106 is used as a member interposed between the moving plate 86 and the shaft 100. However, the present invention is not limited to this as long as the member has elasticity.

In the present embodiment, the glass molded body manufacturing apparatus shown in FIG. 1 has eight processing chambers, and the manufacturing apparatus shown in FIG. 7 has nine processing chambers. The apparatus can increase or decrease the number of processing chambers as needed. At that time, the rotation angle of the rotary table can be changed as appropriate according to the number of processing chambers.

Further, in the above-described embodiment, a manufacturing apparatus that performs various processes including a pressing process while conveying the mold unit 8 on which the molding die 52 is placed on each of the plurality of support portions 12B standing on the mold support base 12. However, the present invention can also be applied to an apparatus that simultaneously presses a plurality of forming dies without using the conveying mold support 12. Furthermore, as in the above-described embodiment, the forming mold 52 is linearly replaced with a manufacturing apparatus that performs various processes while intermittently rotating the forming mold 52 along the transport path of the circular track by the rotary table 4. The present invention can also be applied to a manufacturing apparatus that transports.

Here, modified examples related to the present invention will be described below.
In the present invention, the elastic member is incorporated into the press mechanism, but it is also conceivable to incorporate the elastic member into the mold support member. FIG. 9 is a vertical cross-sectional view showing a configuration of a modified example of a die support member in which a coil spring is incorporated in a press mechanism. As shown in the figure, a mold support member 300 according to a modified example includes a plate-like base portion 302, a plurality of cylindrical column portions 304 erected on the base portion 302, a cylindrical shaft portion 306A, and a shaft portion 306A. A support portion 306 having a pedestal portion 306B connected to the coil portion 308, and a coil spring 308 disposed on the outer periphery of the column portion 304. The base portion 302, the column portion 304, and the support portion 306 are made of the same material as that of the mold support base 12 of the above embodiment.

The outer diameter of the shaft portion 306A of the support portion 306 is substantially equal to the inner diameter of the column portion 304, whereby the support portion 306 is guided in the vertical direction by the column portion 304.

The coil spring 308 has a lower end in contact with the base portion 302 and an upper end in contact with the lower surface of the pedestal portion 306B of the support portion 306. Accordingly, the support portion 306 is supported by the coil spring 308 in a state where the lower surface of the pedestal portion 306B of the support portion 306 is separated from the upper end of the column portion 304. A coil spring 308 having a predetermined spring constant corresponding to the press load of the mold 52 is used.

The plurality of press heads 310 are provided corresponding to the molding die 52, and are driven by, for example, one actuator (not shown) and can be advanced and retracted in the vertical direction.

When the plurality of press heads 310 are lowered by the actuator, the lower surface of the press head 310 comes into contact with the upper surface of the mold 52. Further, when the press head 310 is lowered, the coil spring 308 resists the press load, so that the press load acts on the mold 52.

When the press head 310 is further lowered, the lower surface of the pedestal portion 306B comes into contact with the upper end of the column portion 304. In this manner, the lowering of the press head 310 is stopped in a state where the lower surface of the pedestal portion 306B is in contact with the upper end of the column portion 304. In this modification, the press head 310 stops descending when the lower surface of the pedestal portion 306B comes into contact with the upper end of the column portion 304. However, the length of the shaft portion 306A is changed to The lowering of the press head 310 may be stopped when the lower end comes into contact with the base 302.
Even when the mold support base 12 having such a configuration is used, the plurality of molds 52 can be pressed with a uniform press load as in the above-described embodiment.

The present invention will be summarized below with reference to the drawings.
The glass molded body manufacturing apparatus 1 according to the present embodiment includes a glass provided with a press mechanism 70 that simultaneously presses a plurality of molds 52 containing glass materials in a press chamber 26 formed in the housing 2. As shown in FIG. 4, the press mechanism 70 is provided corresponding to a plurality of molds 52, and a plurality of press heads 102 that individually press the molds 52, respectively, A plurality of shafts 100 respectively connected to the plurality of press heads 102 and extending in parallel with each other through the upper wall 2A of the housing 2, actuators 80 provided outside the housing 1, A moving plate 86 disposed outside and pressed and moved toward the mold 52 by the actuator 80, and a coil disposed outside the housing 2 and compressible in the moving direction of the moving plate 86. The moving plate 86 is pressed and moved toward the forming die 52 by the actuator 80 to press the plurality of shafts 100 and the press head 102 toward the forming die 52 via the coil spring 106. Move.

In the method for manufacturing the glass molded body of the present embodiment, the press mechanism 70 simultaneously presses a plurality of molding dies 52 containing glass materials in the press chamber 26 formed in the housing 2. As shown in FIG. 4, the press mechanism 70 is provided corresponding to the plurality of molds 52, and each of the plurality of press heads 102 presses the molds individually, and each of the plurality of press heads 102. A plurality of shafts 100 that are connected to each other and extend to the outside through the upper wall 2A of the housing 2 in parallel with each other, an actuator 80 provided outside the housing 2, and an actuator 80 disposed outside the housing 2 A movable plate 86 that is pressed and moved toward the molding die 52 by means of a coil spring 106 that is disposed outside the housing 2 and can be compressed in the moving direction of the movable plate 86. In the pressing step, the moving plate 86 is pressed and moved toward the forming die 52 by the actuator 80, thereby pressing the plurality of shafts 100 and the press head 102 toward the forming die 52 via the coil spring 106. Move.

DESCRIPTION OF SYMBOLS 1,150 Glass forming body manufacturing apparatus 2 Case 4 Turntable 6 Inner casing 8 Mold unit 12 Mold support 12B Support part 20 First heating chamber 22 Second heating chamber 24 Soaking chamber 26 Press chamber 28 First gradual Cold chamber 30

Second annealing chamber

32, 34, 36, 38, 40, 42 Heater 44 Rapid cooling section 46 Loading / unloading section 52 Mold 60 Glass material 70 Press mechanism 72 Support mechanism 80 Actuator 81 Guide mechanism 82 Piston rod 84 Linear Bush 86 Moving plate 88 Rod 90 Shaft holder 92 Linear bush 100 Shaft 101 Locking portion 102 Press head 104 Nut 106 Coil spring 110 Housing cover material 112 Oil seal 114 Linear bush 116 Heat shield member 119 Casing cover material 120 Heating chamber 122 First Soaking chamber 124 First press chamber 12 The first slow cooling chamber 128 second Hitoshinetsushitsu 130 second press chamber 132 second slow cooling chamber 200 type support table 202 supporting unit

Claims

An apparatus for producing a glass molded body having a press mechanism for simultaneously pressing a plurality of molds containing glass materials in a press chamber formed in a housing,
The press mechanism is
A plurality of press heads provided corresponding to the plurality of molds and individually pressing the molds;
A plurality of shafts respectively connected to the plurality of press heads and extending in parallel to each other through the upper wall of the housing;
An actuator provided outside the housing;
A moving member that is disposed outside the casing and is pressed and moved toward the mold by the actuator;
An elastic member disposed outside the housing and compressible in the moving direction of the moving member;
Have
The movable member is pressed and moved toward the mold by the actuator, whereby the plurality of shafts and the press head are pressed and moved toward the mold via the elastic body. apparatus.
2. The glass molded body according to claim 1, further comprising a first guide member that is provided in a portion of the upper wall of the housing through which the shaft passes and guides the plurality of shafts to move in the axial direction. Manufacturing equipment.
The glass molded body according to claim 1, further comprising a second guide member that is provided outside the housing and guides the moving member so as to move in an axial direction of the plurality of shafts. apparatus.
Furthermore, the glass molding of any one of Claim 1 to 3 provided with the sealing member which is provided in the part through which the said shaft of the said housing penetrates, and seals between these shafts and the said housing | casing. Body manufacturing equipment.
The elastic body is a coil spring;
The shaft includes a locking portion provided outside the housing,
The coil spring is interposed between the locking portion and the moving member,
The manufacturing apparatus of the glass molded object of any one of Claim 1 to 4.
The coil spring is sheathed on the shaft,
The manufacturing apparatus of the glass molded object of Claim 5.
A heater case provided in the housing;
The press chamber is provided in the heater case,
The plurality of shafts penetrates the upper wall of the heater case,
The manufacturing apparatus of the glass molded object of any one of Claim 1 to 6.
A method for producing a glass molded body,
The press mechanism includes a step of simultaneously pressing a plurality of molds containing glass materials in a press chamber formed in the housing,
The press mechanism is
A plurality of press heads provided corresponding to the plurality of molds and individually pressing the molds;
A plurality of shafts respectively connected to the plurality of press heads and extending in parallel to each other through the upper wall of the housing;
An actuator provided outside the housing;
A moving member that is disposed outside the casing and is pressed and moved toward the mold by the actuator;
An elastic member disposed outside the housing and compressible in the moving direction of the moving member;
Have
In the pressing step, the moving member is pressed and moved toward the mold by the actuator, whereby the plurality of shafts and the press head are pressed and moved toward the mold through the elastic body. A method for producing a glass molded body.