Method and device for precisely forming low-melting-point large-size optical glass ball

Abstract

The invention discloses a method and a device for precisely forming a low-melting-point large-size optical glass ball, and belongs to the technical field of optical glass forming. The device mainly solves the problem of large-size forming of the existing low-melting-point glass balls with precise dropping of more than 2g. The method is mainly characterized by comprising the following steps: (1) storing high-temperature molten glass discharged from a smelting furnace in a feeding bin, and cooling to a set viscosity; (2) extruding the molten glass in the feeding bin to accelerate the molten glass to converge into a cluster at a feeding pipe nozzle connected with the feeding bin and fall into a first forming mold positioned below; (3) enabling the glass liquid drops falling into the first forming mold to suspend and rotate under the action of upward air flow and lateral air flow, and accelerating to shape the glass liquid drops into an optical glass ball prefabricated part; and (4) the first forming mold is placed on the periodic rotating platform, and continuous production can be achieved. The device is mainly used for precise dropping forming of large-size glass balls of low-melting-point optical glass.

Description

Technical Field

[0001] The invention belongs to the technical field of optical glass molding, and in particular relates to a method and a device for precision drip molding of large-size glass balls of low-melting-point optical glass. Background Art

[0002] As the size of optical systems gradually decreases and their functions increase, the requirements for miniaturization, lightness and high performance of optical components are put forward. This makes the demand for aspheric lenses that can improve imaging quality increasingly large. Aspheric lenses are mostly made by precision molding. This method is to make glass materials into preforms by cold processing. Glass precision molding technology is particularly suitable for the production of small and medium-caliber high-precision aspheric lenses. This technology can efficiently mass-produce aspheric lenses. Glass precision molding technology requires low-cost and large-scale precision preforms. The manufacturing process of precision preforms can currently be divided into two types: one is to remove the processing to make precision preforms; the other is to use the drip forming method to make precision preforms. In the first method, the removal of precision preforms requires cutting, grinding, polishing and other processes. These processes will remove a large amount of excess material and there will be a lot of waste; the second method can directly form a smooth surface precision preform without scratches and pitting. It is very suitable for making precision molded precision preforms, and can be directly precision molded without subsequent processes. Generally, low melting point glass is used in precision molding. Such glass is usually produced by precious materials such as rare earth, and the cost of raw materials is high. Therefore, the use of precision drop forming method to improve the utilization rate of raw materials and reduce the production cost of prefabricated parts is a problem that needs to be solved urgently.

[0003] The specific process of glass ball precision drop forming method is as follows: the forming device is as follows Figure 1 As shown, the glass liquid is dripped into the second molding die 24 below by using a leaking pipe 1. After receiving the glass liquid, the second molding die 24 slowly descends. After reaching the target weight, the second molding die 24 descends rapidly, and the surface tension of the molten glass liquid is separated to form droplets. The second suspended air supply pipe 25 at the bottom of the second molding die 24 introduces an air flow with a certain pressure, so that the droplets float above the second molding die 24 without contacting the surface of the second molding die 24. The precision droplets obtained by the precision droplet forming method require suitable viscosity and volume, which requires a precise feeding device. The current feeding device uses the leaking pipe 1 to heat the first leaking pipe electrode sheet 4, the third leaking pipe electrode sheet 22 and the fourth leaking pipe electrode sheet 23 to a certain temperature for feeding. The material properties and viscosity of the glass are relatively fixed. When feeding with the same diameter of the material tube, the droplets are separated from the material tube nozzle and enter the second molding die 24 by increasing the weight to a certain extent to overcome the surface tension.

[0004] The above problems with glass ball dripping are: first, relying on gravity to overcome surface tension is a passive process. The weight of the ball is related to the temperature, diameter and material properties of the material tube. In order to obtain the appropriate viscosity and weight of the drop of a certain brand, the inner diameter of the material tube needs to be repeatedly corrected. Second, the material tube needs to be replaced when changing specifications and adjusting the molding amount. Under a certain viscosity, if the weight of the drop is to be changed, the diameter of the material tube must also be changed. After the diameter of the material tube and the viscosity of the glass are fixed, the frequency of dropping the ball is also relatively fixed. Therefore, the molding cycle of the drop is also limited to a certain range. When the molding cycle of the product needs to be adjusted, the platinum material tube also needs to be replaced. In this way, in order to achieve precise dripping, the platinum material tube needs to be replaced repeatedly. Generally, optical glass uses platinum as the material tube. The replacement of the platinum material tube is a very costly operation and will increase the labor intensity of the operator. Third, it is difficult to produce large-sized ball materials. Due to the limitation of relying on surface tension to support the glass liquid, the glass liquid gathered at the nozzle of the material tube is limited, and it is difficult to produce large-sized glass balls of more than 2 grams. Summary of the invention

[0005] The purpose of the present invention is to design a method and device for forming a low-melting-point optical glass drop ball in a targeted manner in view of the above-mentioned shortcomings.

[0006] The technical solution of the method of the present invention is: a method for precision molding of low-melting-point large-size optical glass balls, which is used to produce precision molding of low-melting-point glass balls, and is characterized by comprising the following steps: (1) The high-temperature glass liquid coming out of the furnace is first stored in the feed bin and cooled to the set viscosity; (2) by squeezing the glass liquid in the feeding bin, the glass liquid is accelerated to gather into a ball at the nozzle of the feeding pipe connected to the feeding bin and fall into the first forming mold located below; (3) The glass droplets falling into the first molding die are suspended and rotated by the upward airflow and the lateral airflow, thereby accelerating the shaping into optical glass ball preforms.

[0007] The technical solution of the method of the present invention comprises the following steps: (1) The high-temperature glass liquid from the melting furnace is first flowed to the supply bin for storage and cooled to the softening temperature Ts: +100~250℃, so that the glass liquid reaches the set viscosity; (2) squeezing the glass liquid in the feed bin at the bottom of the feed bin by means of an extrusion device, accelerating the glass liquid to gather into a ball at the needle-shaped nozzle of the feed pipe connected to the feed bin and fall into the first molding mold located below, while blocking the high-temperature glass liquid inlet of the feed bin; the edge of the feed bin is provided with a telescopic ring which reduces the volume of the cavity when the bottom is squeezed; (3) The glass droplets falling into the first molding die are suspended and rotated in the first molding die under the action of the airflow from the bottom to the top and the airflow from the sides to the sides, and are cooled to a viscosity of 10 to 200 poise, and are rotated and cooled in the first molding die to form an optical glass ball preform.

[0008] The technical solution of the device of the present invention is: a device for precision molding of low-melting-point large-size optical glass balls, including a material receiving crucible, a leakage pipe and a first molding mold, the material receiving crucible is connected to the upper end of the leakage pipe, the bottom of the first molding mold is provided with air holes and a suspended air supply pipe, and the leakage pipe is provided with a leakage pipe electrode sheet, which is characterized in that: it also includes a feed bin, a feed pipe and an extrusion device; wherein the lower end of the leakage pipe penetrates into the feed bin; the extrusion device is arranged below the feed bin and is extruded and matched with the bottom of the feed bin; the feed pipe is connected to the feed bin; the first molding mold is arranged below the nozzle of the feed pipe, and one or more air holes and a rotating air supply pipe are provided on the side; the feed pipe is provided with a feed pipe electrode sheet.

[0009] In the technical solution of the device of the present invention, a leakage pipe plug is provided at the bottom of the feed bin which cooperates with the lower port of the leakage pipe; when the leakage pipe plug is squeezed by the squeezing device, it contacts the lower port of the leakage pipe until the lower port of the leakage pipe is blocked.

[0010] In the technical solution of the device of the present invention, a telescopic ring is arranged at the horizontal circumferential edge of the feed bin; when the bottom of the feed bin is squeezed by the squeezing device, the telescopic ring reduces the volume of the feed bin cavity and increases the pressure.

[0011] In the technical solution of the device of the present invention, a leakage pipe in the feed bin is provided with a leakage pipe buffer ring; the leakage pipe buffer ring is used to mitigate the impact of the leakage pipe plug on the leakage pipe.

[0012] In the technical solution of the device of the present invention, the first molding die is provided with a spherical cavity; the first rotating air supply pipe and the second rotating air supply pipe are respectively provided on opposite sides of the spherical cavity.

[0013] The feeding pipe nozzle described in the technical solution of the device of the present invention is needle-shaped; the leakage pipe, feeding bin and feeding pipe are respectively provided with leakage pipe thermocouple, feeding bin thermocouple and feeding pipe thermocouple; the leakage pipe electrode sheet is the first leakage pipe electrode sheet and the second leakage pipe electrode sheet; the feeding pipe electrode sheet is the first feeding pipe electrode sheet and the second feeding pipe electrode sheet; the leakage pipe, feeding bin and feeding pipe are connected end to end to form a closed whole.

[0014] The leakage pipe, the feed bin, the feed bin telescopic ring and the feed pipe described in the technical solution of the device of the present invention are all made of platinum, platinum-rhodium alloy or platinum-yellow alloy.

[0015] The technical solution of the device of the present invention also includes a rotating platform; the first molding die is placed on the rotating platform.

[0016] The principle of the present invention is as follows: the high-temperature glass liquid flowing out of the discharge pipe of the melting furnace enters the feeding bin through the leakage pipe, and then is transferred and the temperature is controlled in the feeding bin to adjust the glass liquid to a suitable viscosity, and then is output through the feeding pipe and gathered into droplets at the nozzle. After the droplets reach a certain weight, they fall into the forming mold, and are suspended under the action of the upward airflow in the forming mold, and rotate and cool under the action of the left and right airflows to form glass balls. At this time, not only can the flow rate of the glass liquid be changed by adjusting the viscosity, but the flow rate of the glass liquid can also be adjusted by squeezing the feeding bin without changing the viscosity.

[0017] Beneficial effects of the present invention: 1. It can instantly provide a large amount of glass liquid, which is conducive to the molding of large-sized glass balls. The high-temperature glass liquid flows out of the leakage pipe and does not directly enter the feeding pipe to cool to a certain temperature, gather into droplets and fall into the molding mold to form glass balls. Instead, it is first stored in a feeding bin at a certain temperature, and then output to the nozzle through the feeding pipe to gather into droplets. The large volume of the feeding bin increases the flow rate and provides enough glass liquid to reserve for the molding of large-sized glass balls; 2. By adding the function of the extrusion feed bin, power is provided for the large flow rate of molten glass required for large-sized glass. The extrusion feed bin can not only increase the flow rate of molten glass by adjusting the viscosity, but also increase the flow rate of molten glass by extruding the feed bin when the viscosity is constant. This is particularly important for the drop ball, because the weight of the drop ball is related to the inner diameter of the feed tube and the viscosity of the molten glass. The drop ball has an optimal molding viscosity, and changes in viscosity will affect the roundness of the glass ball. In the absence of external force, the material properties of the glass grade are constant, and the unit weight of the drop ball determines the inner diameter of the feed tube and the discharge amount. After the inner diameter of the feed tube is fixed, it is difficult for the drop ball to increase the discharge amount, but it can be easily achieved by extruding the feed bin. It solves the problem that the flow rate of molten glass is slow only by controlling the temperature and viscosity, and the viscosity can also be fixed to quickly adjust the flow rate of the molten glass through pressure control; 3. By squeezing the feed bin to make it deform instantly and then recover, the glass liquid can be accelerated to gather into droplets at the feed nozzle. Compared with other methods, the outstanding feature is to change the passive feeding that relies on gravity to overcome surface tension to form droplets, and actively squeeze the glass liquid to feed, and cooperate with the conical feed nozzle to make the glass liquid easily separate from the feed nozzle to form droplets. When the squeezing force disappears, the feed bin returns to its original shape, which can accelerate the glass liquid in the leaking pipe to flow to the feed bin; 4. The outlet of the leakage pipe is equipped with a backflow prevention device to prevent the glass liquid from returning to the leakage pipe when the feeding bin is squeezed, so that the squeezed glass liquid only flows to the feeding pipe; 5. It can reduce the frequency and quantity of replacing the material pipe. Changing the specifications only requires replacing the partial material pipe, avoiding the need to replace the entire material pipe when changing the brand and specification, reducing the loss cost of platinum and reducing labor costs; 6. Compared with other methods, it is more convenient to realize the automated production of low-melting-point large-size drop balls at one time.

[0018] The invention is mainly used for the precise drop forming of large-size glass balls of low-melting-point optical glass. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the structure of a drop ball forming device used in existing low melting point glass.

[0020] Figure 2 It is a structural schematic diagram of the present invention.

[0021] Figure 3 It is a partial structural schematic diagram of the present invention.

[0022] Figure 4 It is a schematic diagram of the glass liquid droplet of the present invention before it falls into the first forming mold.

[0023] Figure 5 It is a schematic diagram of the glass liquid drop after falling into the first forming mold of the present invention.

[0024] Figure 6 yes Figure 5 Top view of the .

[0025] Figure 7 It is a top view of the mold and the rotating platform.

[0026] Explanation of the reference numerals: 1-leakage pipe; 2-feeding bin; 3-feeding bin telescopic ring; 4-first leakage pipe electrode sheet; 5-second leakage pipe electrode sheet; 6-first feeding pipe electrode sheet; 7-feeding pipe; 8-second feeding pipe electrode sheet; 9-glass drop; 10-first forming mold; 11-first rotating air supply pipe; 12-second rotating air supply pipe; 13-suspended air supply pipe; 14-leakage pipe plug; 15-extrusion device; 16-leakage pipe thermocouple; 17-feeding bin thermocouple; 18-feeding pipe thermocouple; 19-receiving crucible; 20-leakage pipe buffer ring; 21-rotating platform; 22-third leakage pipe electrode sheet; 23-fourth leakage pipe electrode sheet; 24-second forming mold; 25-second suspended air supply pipe. DETAILED DESCRIPTION

[0027] like Figure 2As shown. An embodiment of a device for precision molding of low-melting-point large-size optical glass balls of the present invention is composed of a receiving crucible 19, a leaking pipe 1, a feeding bin 2, a feeding pipe 7, a first molding die 10, and an extrusion device 15. Among them, the receiving crucible 19 is connected to the upper end of the leaking pipe 1, the lower end of the leaking pipe 1 penetrates into the feeding bin 2, the feeding pipe 7 is connected to the feeding bin 2, the extrusion device 15 is arranged below the feeding bin 2, and the first molding die 10 is arranged below the nozzle of the feeding pipe 7. The material of the leaking pipe 1, the feeding bin 2 and the feeding pipe 7 can be selected from platinum, platinum-rhodium alloy and platinum-yellow alloy, and is electrically heated through an electrode sheet, on which a thermocouple is provided to control the temperature using a temperature controller.

[0028] The bottom of the receiving crucible 19 is funnel-shaped and serves as an inflow channel for the glass liquid from the melting furnace. A discharge port is provided in the center of the bottom.

[0029] The leakage pipe 1 is provided with a first leakage pipe electrode sheet 4, a second leakage pipe electrode sheet 5 and a leakage pipe thermocouple 16 to provide glass liquid for the device. The leakage pipe 1 is provided with a leakage pipe buffer ring 20 on the pipe section located in the feed bin 2. The leakage pipe buffer ring 20 is gyro-shaped to prevent the leakage pipe 1 from being deformed due to excessive extrusion.

[0030] The feeding bin 2 is in the shape of a disc and is located at the bottom of the leakage pipe 1. Its volume is many times larger than that of the feeding material, so that the melted glass liquid can be stored here. At the same time, it is responsible for the transfer and viscosity adjustment of the glass liquid to adapt to glass balls of different particle sizes. A foldable telescopic ring 3 is also provided around the edge of the middle part of the feeding bin 2. The upper and lower parts of the feeding bin 2 are connected to form a smooth inner wall through the telescopic ring 3. When the bottom end surface of the feeding bin 2 is squeezed by the external force of the squeezing device 15, the telescopic ring 3 of the feeding bin is deformed, the volume of the feeding bin 2 becomes smaller, and the glass liquid is squeezed at the same time, accelerating the gathering of the glass liquid at the nozzle of the feeding pipe 7. When the external force disappears, the volume of the feeding bin 2 is restored. The material of the telescopic ring 3 of the feeding bin can be selected from platinum, platinum-rhodium alloy and platinum-yellow alloy. A leakage pipe plug 14 is also provided at the bottom of the feed bin 2. The diameter of the leakage pipe plug 14 is slightly larger than the outlet diameter of the leakage pipe 1. When the feed bin 2 is squeezed and moves upward, the leakage pipe plug 14 just blocks the outlet of the leakage pipe 1 to prevent the glass liquid from flowing back. A feed bin thermocouple 17 is provided on the feed bin 2, and the periphery is heated by electric radiation.

[0031] The upper end of the feed pipe 7 is connected to the side of the feed bin 2 above the feed bin telescopic ring 3, and the outer diameter of the nozzle gradually becomes thinner and needle-shaped, which can reduce the difficulty of the glass droplet to separate from the feed pipe nozzle due to surface adsorption tension and accelerate the shedding of the glass liquid droplet 9. The feed pipe 7 is provided with a first feed pipe electrode sheet 6, a second feed pipe electrode sheet 8 and a feed pipe thermocouple 18.

[0032] The extrusion device 15 is arranged below the feed bin 2 and is extruded and matched with the bottom of the feed bin 2. The extrusion device 15 has a circular plane, which is smaller in diameter than the feed bin 2. The circular plane and the feed bin 2 are coaxial, and can move up and down at a frequency of 2-50 times / minute according to demand. When it rises, it pushes the feed bin 2 when it moves upward, and when it drops to the bottom, it is out of contact with the feed bin 2, and the feed bin 2 is in a relaxed state. The extrusion device 15 cooperates with the feed bin 2 and the feed pipe 7, so that the feed pipe 7 provides glass drops with suitable viscosity, weight and frequency.

[0033] The first molding mold 10 is arranged directly below the feed pipe 7. The first molding mold 10 is provided with a spherical cavity, and the bottom of the spherical cavity is provided with air holes and a first suspended air supply pipe 13. The first rotating air supply pipe 11 and the second rotating air supply pipe 12 are respectively provided on opposite sides of the spherical cavity. When the glass droplet enters the first molding mold 10, due to the existence of the upward airflow, the glass droplet 9 is suspended in the first molding mold 10. At the same time, compressed air is passed through the first rotating air supply pipe 11 and the second rotating air supply pipe 12. Under the action of the rotating airflow, the glass droplet 9 rotates at high speed and cools in the first molding mold 10 to form a glass ball. The first molding mold 10 can also be placed on a rotating platform 21, which has a periodic adjustable start and stop function. What kind or model of rotating platform is used for the rotating platform?

[0034] The leakage pipe 1, the feeding bin 2 and the feeding pipe 7 can coordinate with each other to control the temperature and cooperate with the feeding pipe 7 to adjust the viscosity to a suitable range.

[0035] A method for precision molding of low-melting-point large-size optical glass balls, used for precision molding of low-melting-point glass balls, comprises the following steps: (1) The high-temperature glass liquid from the melting furnace is first flowed to the supply bin 2 for storage and cooled to the softening temperature Ts: +100~250℃, so that the glass liquid reaches the set viscosity; (2) The glass liquid in the feed bin 2 is squeezed at the bottom of the feed bin 2 by an extrusion device 15, so as to accelerate the glass liquid to gather into a ball at the needle-shaped nozzle of the feed pipe 7 connected to the feed bin 2 and fall into the first molding die 10 located below, and at the same time, the high-temperature glass liquid inlet of the feed bin 2 is blocked; the edge of the feed bin 2 is provided with a telescopic ring 3 which reduces the volume of the cavity when the bottom is squeezed; (3) The glass droplets falling into the first molding die 10 are suspended and rotated in the first molding die 10 under the action of the airflow from the bottom to the top and the airflow from the sides to the sides, and are cooled to a viscosity of 10 to 200 poises. The glass droplets are rotated and cooled in the first molding die 10 to be molded into optical glass ball preforms.

[0036] The following is an example of the production of D-ZLaF* brand glass drop balls to introduce the specific implementation process. D-ZLaF* brand glass is a low melting point glass with a crystallization temperature of Lt: 770℃ and a softening temperature of Ts: 540℃. It is characterized by long material properties and is often used as a glass brand for drop balls. There are more than 10 specifications of drop balls with a unit weight of 0.2 grams to 20 grams. The output of 0.2 grams per unit weight is less than 50Kg / D, and the output of 20 grams per unit weight is more than 300Kg / D. Because the unit weight of 0.2 grams is light, the molding requires a viscosity of less than 5 poise, and the unit weight of 20 grams requires a viscosity of more than 50 poise. In order to match the appropriate viscosity and output for different specifications, it is necessary to constantly replace the material tube to adapt to the molding of glass drop balls of different specifications. If the output of the same specification needs to increase by more than 20%, the material tube also needs to be replaced. According to the present invention, frequent replacement of the leakage pipe 1 and the feed pipe 7 can be avoided, and the problem of frequent replacement of the feed pipe to match the dripping material specifications and the discharge volume due to changes in the dripping ball specifications and the discharge volume can be avoided. Even if the difference in the dripping ball specifications and the discharge volume changes greatly, only the feed pipe 7 needs to be replaced.

[0037] During production, first press Figure 2 The parts of each part are made and connected in this way, the receiving crucible 19 receives the high-temperature glass liquid released from the melting furnace, and the feeding bin 2 is placed in the auxiliary furnace. First, the temperature of the thermocouples of each part is raised to above 1100°C through the temperature controller until the glass liquid flows out smoothly.

[0038] Further reduce the temperature of each part to the preset process: the temperature range of the thermocouple of the feed bin 2 is 800-850°C, the temperature range of the leakage pipe thermocouple 16 is 850-900°C, and the temperature range of the feed pipe thermocouple 18 is 750-800°C.

[0039] Furthermore, the temperatures of various parts are coordinated with each other to adjust the material quantity and viscosity, so that the glass liquid at the outlet of the feed pipe 7 can gradually fall in the form of drops.

[0040] The viscosity of the glass droplets is further adjusted by adjusting the temperature of the feed bin 2 , and the frequency of the glass droplets falling is adjusted by adjusting the temperature of the feed pipe 7 .

[0041] The preheated first molding mold 10 is further placed directly below the feeding pipe 7 so that the falling glass liquid droplet 9 is located at the center of the cavity of the first molding mold 10 .

[0042] The flow rate of the gas in the suspension vent pipe 13 is further adjusted so that the glass droplet entering the mold is suspended in the center of the first molding mold 10 .

[0043] The first rotating air supply pipe 11 and the second rotating air supply pipe 12 on both sides of the first molding mold 10 are further ventilated to rotate the glass liquid drop 9, and the airflow size of the rotating air supply pipe is gradually adjusted to change the rotation speed of the glass liquid drop 9.

[0044] Furthermore, the rotating airflow cooperates with the suspended airflow to make the glass liquid drop 9 rotate into a precise glass ball in the first molding die 10 .

[0045] The squeezing device 15 is further started, and when the glass liquid begins to gather at the feeding nozzle, the lower part of the feeding bin 2 is squeezed to accelerate the gathering of the glass liquid at the nozzle of the feeding pipe 7. The bottom end surface of the feeding bin 2 is periodically driven by the squeezing device 15 to reciprocate up and down.

[0046] By further repeating the above actions in a cycle, molded parts can be continuously pressed out. For example, if the mold 10 is placed on a rotating large plate 21 of an automatic press, D-ZLaF* brand glass molded parts can be automatically produced in a cycle.

[0047] The technical solution of the present invention can be multiple molding molds, and they are fixed on the circumference of a rotating large disk 21 and arranged in an array. The molding mold 10 is driven by the rotation of the large disk to stop and move repeatedly. When the mold 10 reaches the lower end of the feeding tube, the large disk stops rotating. At this time, the extrusion device 15 moves upward to apply pressure to the lower end of the feeding bin 2. The feeding bin 2 deforms and squeezes the glass liquid inside, so that the glass liquid quickly gathers into a ball at the nozzle 8 of the feeding tube and falls to form a drop. When the glass liquid accumulates to a certain amount, it begins to fall. At this time, the extrusion device 15 descends and the pressure at the lower end of the feeding bin 2 disappears. The glass liquid shrinks due to the reduction of the pressure in the feeding bin 2, which accelerates the separation of the glass liquid from the feeding nozzle 8, so that the glass liquid forms a drop and falls into the molding mold 13. Under the action of the upward rotating airflow in the molding mold 13, it rolls, cools and solidifies into a glass ball. When the rotating large disk 21 makes the molding mold reach a certain mold position, the glass ball is taken out to complete a process of drop molding. Repeating this process can achieve full-automatic molding.

Claims

1. A method for precision molding of low-melting-point large-size optical glass balls, used for precision molding of low-melting-point glass balls, characterized by: The following steps are involved: (1) The high-temperature molten glass coming out of the furnace is first stored in a feed bin (2) and cooled to a set viscosity; (2) by squeezing the glass liquid in the feeding bin (2), the glass liquid is accelerated to gather into a ball at the nozzle of the feeding pipe (7) connected to the feeding bin (2) and fall into the first forming mold (10) located below; (3) The glass droplets falling into the first forming mold (10) are suspended and rotated under the action of the upward airflow and the lateral airflow, thereby accelerating the shaping into optical glass ball preforms.

2. According to claim 1, a method for precision molding of large-size low-melting-point optical glass balls, characterized in that The following steps are involved: (1) The high-temperature molten glass from the melting furnace is first flowed to the supply bin (2) for storage and cooling to the softening temperature Ts: +100~250℃, so that the molten glass reaches the set viscosity; (2) squeezing the glass liquid in the feed bin (2) at the bottom of the feed bin (2) by means of an extrusion device (15), accelerating the glass liquid to gather into a mass at the needle-shaped nozzle of a feed pipe (7) connected to the feed bin (2) and fall into a first molding die (10) located below, while blocking the high-temperature glass liquid inlet of the feed bin (2); a telescopic ring (3) is provided at the edge of the feed bin (2) so that the volume of the cavity becomes smaller when the bottom is squeezed; (3) The glass droplets falling into the first molding die (10) are suspended and rotated in the first molding die (10) under the action of the airflow from the bottom to the top and the airflow from the sides to the sides, and are cooled to a viscosity of 10 to 200 poise, and are rotated and cooled in the first molding die (10) to form an optical glass ball preform.

3. A device for the method of precision molding a low-melting-point large-size optical glass ball according to claim 1 or 2, comprising a receiving crucible (19), a leaking pipe (1) and a first molding die (10), wherein the receiving crucible (19) is connected to the upper end of the leaking pipe (1), the bottom of the first molding die (10) is provided with an air hole and a suspended air supply pipe (13), and the leaking pipe (1) is provided with a leaking pipe electrode sheet, wherein: It also comprises a feed bin (2), a feed pipe (7) and an extrusion device (15); wherein the lower end of the leakage pipe (1) penetrates into the feed bin (2); the extrusion device (15) is arranged below the feed bin (2) and is extruded and matched with the bottom of the feed bin (2); the feed pipe (7) is connected to the feed bin (2); the first forming die (10) is arranged below the nozzle of the feed pipe (7), and one or more air holes and a rotating air supply pipe are provided on the side; and a feed pipe electrode sheet is provided on the feed pipe (7).

4. The device for precision molding of low-melting-point large-size optical glass balls according to claim 3, characterized in that: The bottom of the feed bin (2) is provided with a leakage pipe plug (14) which cooperates with the lower end of the leakage pipe (1); when the leakage pipe plug (14) is squeezed by the squeezing device (15), it contacts the lower end of the leakage pipe (1) until the lower end of the leakage pipe (1) is blocked.

5. The device for precision molding of low-melting-point large-size optical glass balls according to claim 4, characterized in that: A telescopic ring (3) is provided at the horizontal circumferential edge of the feed bin (2); when the telescopic ring (3) is squeezed by the squeezing device (15) at the bottom of the feed bin (2), the volume of the cavity of the feed bin (2) becomes smaller and the pressure becomes larger.

6. The device for precision molding of low-melting-point large-size optical glass balls according to claim 5, characterized in that: A leakage pipe buffer ring (20) is provided on the leakage pipe (1) in the feed bin (2); the leakage pipe buffer ring (20) is used to mitigate the impact of the leakage pipe plug (14) on the leakage pipe (1).

7. A device for precision molding of low-melting-point large-size optical glass balls according to any one of claims 3 to 6, characterized in that: The first molding die (10) is provided with a spherical cavity; the first rotating air supply pipe (11) and the second rotating air supply pipe (12) are respectively disposed on opposite sides of the spherical cavity.

8. The device for precision molding of low-melting-point large-size optical glass balls according to any one of claims 3 to 6, characterized in that: The nozzle of the feed pipe (7) is needle-shaped; the leaking pipe (1), the feed bin (2) and the feed pipe (7) are respectively provided with a leaking pipe thermocouple (16), a feed bin thermocouple (17) and a feed pipe thermocouple (18); the leaking pipe electrode sheet is a first leaking pipe electrode sheet (4) and a second leaking pipe electrode sheet (5); the feed pipe electrode sheet is a first feed pipe electrode sheet (6) and a second feed pipe electrode sheet (8); the leaking pipe (1), the feed bin (2) and the feed pipe (7) are connected end to end to form a closed whole.

9. The device for precision molding of low-melting-point large-size optical glass balls according to any one of claims 3 to 6, characterized in that: The material of the leakage pipe (1), the feed bin (2), the feed bin telescopic ring (3) and the feed pipe (7) are all platinum, platinum-rhodium alloy or platinum-yellow alloy.

10. The device for precision molding of low-melting-point large-size optical glass balls according to any one of claims 3 to 6, characterized in that: It also includes a rotating platform; the first molding die (10) is placed on the rotating platform (21).

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