Pressure control device for high temperature fusion casting method of preparing fused quartz product

Abstract

The application relates to the technical field of quartz melting equipment, and discloses a pressure control device for preparing fused quartz products by a high-temperature melting and casting method, which comprises a base, a material injection pipeline rotatably arranged on the base, a vibration pressure reduction mechanism, a driving mechanism and an adjusting mechanism arranged on the base; the vibration pressure reduction mechanism is used for driving the material injection pipeline to reciprocatingly swing based on an axis to form a shearing force on a melt; the driving mechanism is used for driving the vibration pressure reduction mechanism to operate; and the adjusting mechanism is used for adjusting the reciprocating swing frequency of the material injection pipeline according to the discharging speed of the quartz melt. The pressure control device for preparing fused quartz products by the high-temperature melting and casting method drives the material injection pipeline to reciprocatingly swing based on the axis through the vibration pressure reduction mechanism, applies an alternating shearing stress to the quartz melt to reduce the apparent viscosity of the quartz melt, and automatically adjusts the swing frequency through a transmission assembly according to the discharging speed change of the impeller, so that negative feedback self-adaptive control of the melt pressure is realized.

Description

Technical Field

[0001] This invention relates to the field of quartz melting and casting equipment technology, specifically a pressure control device for preparing molten quartz products by high-temperature melting and casting. Background Technology

[0002] High-temperature melting casting is a common process for preparing fused silica products. Its basic principle is to melt quartz raw materials at high temperatures and then inject them into a mold to form the product. During the injection molding process of fused silica products, the melt pressure within the injection channel is a key process parameter affecting product quality—excessive pressure can lead to flash in the mold and increased internal stress in the product, while insufficient pressure can cause incomplete filling and surface defects. The viscosity of molten quartz is extremely high, and it increases exponentially with decreasing temperature. This results in extremely high flow resistance within the injection channel, maintaining a persistently high driving pressure required for normal injection.

[0003] To reduce melt pressure, existing technologies typically employ methods such as increasing the melting and casting temperature or increasing the injection pressure. However, the former increases energy consumption and equipment burden, while the latter may exacerbate product defects. How to effectively reduce the melt pressure within the injection pipe without significantly altering the process temperature, while simultaneously enabling the pressure control process to adapt to changes in the discharge rate, has become a pressing technical problem in this field. Summary of the Invention

[0004] This invention provides a pressure control device for preparing molten quartz products by high-temperature melting and casting. It has the beneficial effect of applying alternating shear stress to the quartz melt to reduce its apparent viscosity and achieving negative feedback adaptive control of the melt pressure, thus solving the problems mentioned in the background art.

[0005] The present invention provides the following technical solution: a pressure control device for preparing fused silica products by high-temperature melting and casting, comprising a base, on which an injection pipe is rotatably mounted, and a vibration pressure reduction mechanism, a driving mechanism and an adjustment mechanism are also provided on the base; The vibration pressure reducing mechanism is used to drive the injection pipe to reciprocate based on the axis to generate shear force on the melt. The driving mechanism is used to drive the vibration pressure reducing mechanism to operate. The adjusting mechanism is used to adjust the reciprocating oscillation frequency of the injection pipe according to the discharge speed of the quartz melt. The adjusting mechanism includes an impeller rotatably installed inside the injection pipe, the impeller being driven to rotate by the molten quartz. The driving mechanism includes a turntable rotatably mounted on the base, and a first sprocket is provided on the turntable. The first sprocket includes a plurality of arc-shaped teeth slidably mounted on the turntable, and the plurality of arc-shaped teeth form a complete sprocket.

[0006] As an optional solution for the pressure control device for preparing fused silica products by high-temperature melting and casting method according to the present invention, the adjustment mechanism further includes a first transmission component and a second transmission component; When the speed of the impeller increases, the transmission of the second transmission component and the first transmission component drives several of the arc-shaped teeth to slide outward along the radial direction of the turntable, thereby increasing the diameter of the first sprocket, thereby reducing the speed of the turntable and reducing the oscillation frequency of the injection pipe. When the impeller speed decreases, the second transmission component and the first transmission component drive several of the arc-shaped teeth to slide inward along the radial direction of the turntable, thereby reducing the diameter of the first sprocket, increasing the speed of the turntable and increasing the oscillation frequency of the injection pipe.

[0007] As an optional solution of the pressure control device for preparing fused silica products by high-temperature melting and casting method according to the present invention, wherein: two shock-absorbing brackets are fixedly installed on the base, and the injection pipe is rotatably installed on the two shock-absorbing brackets; The vibration pressure reduction mechanism includes two mounting seats fixedly installed on the base. The two mounting seats are symmetrically distributed based on the injection pipe. A lifting seat is slidably installed on each of the two mounting seats, and a first connecting seat is fixedly installed on each of the two lifting seats. Two first connecting rods are fixedly installed on the injection pipe, and a second connecting rod is slidably installed on each of the two first connecting rods. The two second connecting rods are respectively hinged to the two first connecting seats through hinge pins. The vibration pressure reduction mechanism further includes a first rotating shaft rotatably mounted on the base. Two cams are fixedly mounted on the first rotating shaft. The two cams are slidably connected to the two lifting seats respectively, and the two cams are installed in opposite directions. The two lifting seats perform reciprocating lifting movements with the same frequency and opposite directions to drive the injection pipe to oscillate back and forth based on the axis.

[0008] As an optional solution for the pressure control device for preparing fused silica products by high-temperature melting and casting method according to the present invention, the driving mechanism further includes a motor fixedly installed on the base, the output shaft of the motor is fixedly connected to a second rotating shaft through a reducer, a second sprocket is fixedly installed on the second rotating shaft, and the first sprocket and the second sprocket are connected by chain drive.

[0009] As an optional solution of the pressure control device for preparing fused silica products by high-temperature melting and casting method according to the present invention, the driving mechanism further includes a tensioning component, which includes a third sprocket rotatably mounted on the base and meshing with the chain; A second mounting base is fixedly installed on the base, a third rotating shaft is rotatably installed on the second mounting base, a support plate is fixedly installed on the third rotating shaft, a fourth rotating shaft is rotatably installed on the support plate, and a third sprocket is fixedly installed on the fourth rotating shaft. The tensioning assembly also includes a torsion spring, the two ends of which are fixedly connected to the second mounting base and the support plate, respectively.

[0010] As an optional solution for the pressure control device for preparing fused silica products by high-temperature melting and casting method according to the present invention, the vibration pressure reduction mechanism further includes a third mounting base fixedly installed on the base, a rotating cylinder rotatably installed on the third mounting base, the first rotating shaft fixedly installed on the rotating cylinder, and the turntable fixedly installed on the first rotating shaft.

[0011] As an optional embodiment of the pressure control device for preparing fused silica products by high-temperature melting and casting method according to the present invention, wherein: a plurality of grooves are arranged in a circular pattern on the turntable, and a slider is fixedly installed on each of the plurality of arc-shaped teeth, and the plurality of sliders are respectively slidably connected in the plurality of grooves, and the rotational speed of the turntable is adjusted by adjusting the transmission ratio between the second sprocket and the first sprocket.

[0012] As an optional solution of the pressure control device for preparing fused silica products by high-temperature melting and casting method according to the present invention, wherein: the first transmission component includes a first slide rod slidably mounted on the rotating drum, a connecting ring fixedly mounted on the first slide rod, a plurality of second connecting seats fixedly mounted on the connecting ring, and a third connecting seat fixedly mounted on each of the plurality of slide blocks; The first transmission assembly further includes a plurality of third connecting rods, one end of each of the plurality of third connecting rods being movably hinged to a plurality of second connecting seats via hinge shafts, and the other end of each of the plurality of third connecting rods being movably hinged to a plurality of third connecting seats via hinge shafts.

[0013] As an optional embodiment of the pressure control device for preparing fused silica products by high-temperature melting and casting according to the present invention, the second transmission component includes two second slide rods symmetrically slidably mounted on the fifth rotating shaft of the impeller, both second slide rods being elastically connected to the fifth rotating shaft by springs, and a fourth connecting rod being slidably mounted on the third mounting base, the first slide rod being rotatably connected to the fourth connecting rod.

[0014] As an optional embodiment of the pressure control device for preparing fused silica products by high-temperature melting and casting according to the present invention, wherein: a rotating rod is rotatably mounted on the fourth connecting rod, and the second transmission assembly further includes two fifth connecting rods, one end of each of the two fifth connecting rods being movably hinged to the two second sliding rods via hinge shafts, and the other end of each of the two fifth connecting rods being movably hinged to the rotating rod via hinge shafts.

[0015] The present invention has the following beneficial effects: 1. The pressure control device for preparing molten quartz products by high-temperature melting and casting uses a vibration pressure reduction mechanism to drive the injection pipe to reciprocate based on its axis, so that the inner wall of the injection pipe applies periodic alternating shear stress to the quartz melt, which effectively reduces the apparent viscosity and flow resistance of the melt, thereby reducing the melt pressure in the injection pipe without changing the melting and casting temperature, reducing product defects and improving molding quality.

[0016] 2. The pressure control device for preparing fused silica products by high-temperature melting and casting method, by setting up an impeller, a first transmission component and a second transmission component, utilizes the positive correlation between impeller speed and discharge speed and the square relationship between centrifugal force and speed to automatically convert the change in discharge speed into the change in the diameter of the first sprocket through a purely mechanical transmission path, thereby adjusting the oscillation frequency of the injection pipe, realizing negative feedback adaptive pressure control based on discharge speed, without the need for electronic sensors and controllers, and suitable for high-temperature and harsh working conditions.

[0017] 3. The pressure control device for preparing fused silica products by high-temperature melting and casting method, by setting the first sprocket as a variable diameter sprocket structure composed of several radially sliding arc-shaped teeth, combined with the automatic tensioning function of the tensioning component, realizes stepless continuous adjustment of the oscillation frequency of the injection pipe. The adjustment process does not require stopping the machine and has a fast response speed, ensuring the stability of melt pressure and the consistency of product quality under different working conditions. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0019] Figure 2 This is a schematic diagram of the first cross-sectional structure of the present invention.

[0020] Figure 3 For the present invention Figure 2 A magnified schematic diagram of the structure at point A in the middle.

[0021] Figure 4 This is a schematic diagram of the second cross-sectional structure of the present invention.

[0022] Figure 5 This is a schematic diagram of the exploded structure of the vibration decompression mechanism in this invention.

[0023] Figure 6 This is an exploded structural diagram of the adjusting mechanism in this invention.

[0024] Figure 7 This is an exploded structural diagram of the driving mechanism in this invention.

[0025] Figure 8 This is a schematic diagram of the tensioning component in this invention.

[0026] In the diagram: 1. Base; 2. Injection pipe; 3. Impeller; 4. Turntable; 5. First sprocket; 6. Arc-shaped toothed section; 7. Shock-absorbing bracket; 8. First mounting seat; 9. Lifting seat; 10. First connecting seat; 11. First connecting rod; 12. Second connecting rod; 13. First rotating shaft; 14. Cam; 15. Motor; 16. Reducer; 17. Second rotating shaft; 18. Second sprocket; 19. Chain; 20. Third sprocket; 21. ... 21. Mounting base; 22. Third rotating shaft; 23. Support plate; 24. Fourth rotating shaft; 25. Torsion spring; 26. Third mounting base; 27. Rotary cylinder; 28. Slide groove; 29. ​​Slider; 30. First slide rod; 31. Connecting ring; 32. Second connecting seat; 33. Third connecting seat; 34. Third connecting rod; 35. Fifth rotating shaft; 36. Second slide rod; 37. Spring; 38. Fourth connecting rod; 39. Rotating rod; 40. Fifth connecting rod. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] Example 1, please refer to Figures 1-6 A pressure control device for preparing fused silica products by high-temperature melting and casting includes a base 1, an injection pipe 2 rotatably mounted on the base 1, and a vibration pressure reduction mechanism, a drive mechanism, and an adjustment mechanism also provided on the base 1.

[0029] The vibration pressure reducing mechanism is used to drive the injection pipe 2 to reciprocate based on the axis to generate shear force on the melt. The driving mechanism is used to drive the vibration pressure reducing mechanism to run. The adjusting mechanism is used to adjust the reciprocating oscillation frequency of the injection pipe 2 according to the discharge speed of the quartz melt.

[0030] The regulating mechanism includes an impeller 3 that is rotatably installed inside the injection pipe 2, and the impeller 3 is driven to rotate by the quartz melt.

[0031] The drive mechanism includes a turntable 4 rotatably mounted on a base 1, a first sprocket 5 on the turntable 4, and the first sprocket 5 includes several arc-shaped teeth 6 slidably mounted on the turntable 4, and the several arc-shaped teeth 6 form a complete sprocket.

[0032] The adjustment mechanism also includes a first transmission component and a second transmission component.

[0033] When the speed of impeller 3 increases, the transmission of the second transmission assembly and the first transmission assembly drives several arc-shaped teeth 6 to slide outward along the radial direction of turntable 4, thereby increasing the diameter of the first sprocket 5, thereby reducing the speed of turntable 4 and reducing the oscillation frequency of injection pipe 2.

[0034] When the speed of impeller 3 decreases, the transmission of the second transmission assembly and the first transmission assembly drives several arc-shaped teeth 6 to slide inward along the radial direction of turntable 4, thereby reducing the diameter of the first sprocket 5, increasing the speed of turntable 4 and increasing the oscillation frequency of injection pipe 2.

[0035] Two shock-absorbing brackets 7 are fixedly installed on the base 1, and the injection pipe 2 is rotatably installed on the two shock-absorbing brackets 7.

[0036] The vibration pressure reduction mechanism includes two first mounting seats 8 fixedly installed on the base 1. The two first mounting seats 8 are symmetrically distributed based on the injection pipe 2. A lifting seat 9 is slidably installed on each of the two first mounting seats 8. A first connecting seat 10 is fixedly installed on each of the two lifting seats 9.

[0037] Two first connecting rods 11 are fixedly installed on the injection pipe 2. A second connecting rod 12 is slidably installed on each of the two first connecting rods 11. The two second connecting rods 12 are respectively hinged to the two first connecting seats 10 through hinge pins.

[0038] The vibration pressure reduction mechanism also includes a first rotating shaft 13 rotatably mounted on the base 1. Two cams 14 are fixedly mounted on the first rotating shaft 13. The two cams 14 are slidably connected to two lifting seats 9 respectively, and the two cams 14 are installed in opposite directions. The two lifting seats 9 perform reciprocating lifting movements with the same frequency and opposite directions to drive the injection pipe 2 to swing back and forth based on the axis.

[0039] In this embodiment: In actual operation, the pressure control device for preparing fused quartz products using the high-temperature melting and casting method has one end of the injection pipe 2 sealed to the outlet of the melting and casting furnace, and the other end extending above the gate of the quartz product molding die. The molten quartz in the melting and casting furnace flows into the mold cavity through the injection pipe 2 for molding. During this process, the melt pressure in the injection pipe 2 directly affects the filling quality and molding density of the product—excessive pressure can easily lead to flash in the mold and increased internal stress in the product, while insufficient pressure will cause incomplete filling and surface defects in the product.

[0040] To address the aforementioned pressure control issues, this device integrates a vibration pressure reduction mechanism, a drive mechanism, and an adjustment mechanism on the base 1, all of which work in concert. The drive mechanism provides power input to the vibration pressure reduction mechanism, enabling the injection pipe 2 to continuously reciprocate along its own axis.

[0041] The core mechanism of this oscillation lies in the fact that the wall of the injection pipe 2 applies periodic alternating shear stress to the quartz melt attached to its inner wall during the oscillation process. This shear stress is superimposed on the main shear flow generated by the melt's own weight and static pressure difference. The alternating shear stress causes the silicon-oxygen tetrahedral network structure inside the melt to undergo periodic "association-disassociation" transformation, effectively reducing the apparent viscosity of the melt, thereby significantly reducing the driving pressure required to maintain the same flow rate.

[0042] Meanwhile, the periodic pulsating shear force generates additional heat dissipation within the melt, causing a localized increase in melt temperature and further promoting viscosity reduction. Experiments have verified that, under appropriate oscillation frequency and amplitude conditions, the melt pressure within the injection pipe 2 can be reduced, and the extrusion flow rate becomes more uniform and stable.

[0043] Impeller 3 serves as a direct sensing element for the discharge velocity, with its blades extending into the central region of the melt flow channel in the injection pipe 2. As the quartz melt flows through the injection pipe 2, the kinetic energy of the melt propels impeller 3 to rotate continuously. The blades of impeller 3 can be designed with a twisted profile to increase the driving torque of the melt on impeller 3, ensuring reliable start-up even at low flow rates.

[0044] In actual operation, changes in the discharge rate of the upstream melting furnace, fluctuations in the back pressure of the mold cavity, and slight fluctuations in the melt temperature will all cause instantaneous changes in the discharge rate. The rotational speed of impeller 3 responds accordingly in real time, providing an accurate speed signal to the regulating mechanism. Based on this, the regulating mechanism automatically adjusts the oscillation frequency of the injection pipe 2, forming a complete closed-loop adaptive regulating system.

[0045] It should be noted that both ends of the injection pipe 2 are equipped with a double-layer sealing structure at the connecting flanges—the inner layer is a flexible expanded graphite sealing ring, and the outer layer is a ceramic fiber gasket. Flexible expanded graphite has good resilience at high temperatures, effectively compensating for changes in the sealing gap caused by thermal expansion and contraction.

[0046] Ceramic fiber gaskets serve as an auxiliary sealing layer, maintaining a certain sealing capacity even after the graphite sealing ring ages, preventing equipment damage and personnel burns caused by leakage of high-temperature quartz melt.

[0047] Example 2, please refer to Figures 1-8The drive mechanism also includes a motor 15 fixedly mounted on the base 1. The output shaft of the motor 15 is fixedly connected to a second rotating shaft 17 via a reducer 16. A second sprocket 18 is fixedly mounted on the second rotating shaft 17. The first sprocket 5 and the second sprocket 18 are connected by a chain 19.

[0048] The drive mechanism also includes a tensioning component, which includes a third sprocket 20 rotatably mounted on the base 1, and the third sprocket 20 meshes with the chain 19.

[0049] A second mounting base 21 is fixedly installed on the base 1. A third rotating shaft 22 is rotatably installed on the second mounting base 21. A support plate 23 is fixedly installed on the third rotating shaft 22. A fourth rotating shaft 24 is rotatably installed on the support plate 23. A third sprocket 20 is fixedly installed on the fourth rotating shaft 24.

[0050] The tensioning assembly also includes a torsion spring 25, the two ends of which are fixedly connected to the second mounting base 21 and the support plate 23, respectively.

[0051] The vibration reduction mechanism also includes a third mounting base 26 fixedly mounted on the base 1, a rotating cylinder 27 rotatably mounted on the third mounting base 26, a first rotating shaft 13 fixedly mounted on the rotating cylinder 27, and a turntable 4 fixedly mounted on the first rotating shaft 13.

[0052] The turntable 4 has several grooves 28 arranged in a circle, and several arc-shaped teeth 6 are fixedly installed with sliders 29. The sliders 29 are slidably connected in the grooves 28. The rotation speed of the turntable 4 is adjusted by adjusting the transmission ratio between the second sprocket 18 and the first sprocket 5.

[0053] In this embodiment: the vibration pressure reduction mechanism of the pressure control device for preparing fused silica products by high-temperature melting and casting adopts the cam 14-lifting seat 9 transmission method to convert the rotary motion into reciprocating linear motion, and then converts the reciprocating linear motion into the reciprocating oscillation of the injection pipe 2 through the linkage system.

[0054] In actual operation, the rotational power output by the motor 15 is reduced and increased in torque by the reducer 16, and then transmitted to the first rotating shaft 13 through the chain drive of the second sprocket 18, the chain 19 and the first sprocket 5. The first rotating shaft 13 drives the two cams 14 to rotate synchronously. Since the two cams 14 are installed in opposite directions, they alternately push the two lifting seats 9 to perform reciprocating lifting and lowering movements in opposite directions during rotation—one rises while the other falls, and so on.

[0055] It is worth noting that the lifting range of the two lifting seats 9 is determined by the stroke of the cam 14. The swing angle should not be too large to avoid excessive torsional deformation and additional stress at the connection between the injection pipe 2 and the outlet of the melting furnace and the mold gate. The swing angle should also not be too small, otherwise sufficient shear force cannot be generated to effectively reduce the viscosity of the melt.

[0056] During power transmission, the sliding fit between the first connecting rod 11 and the second connecting rod 12 plays a crucial role in displacement compensation: when the injection pipe 2 swings, the end of the first connecting rod 11 on its outer wall actually moves in an arc around the axis of the injection pipe 2. The vertical displacement component of this arc movement deviates from the linear lifting displacement of the lifting seat 9. This deviation is automatically absorbed by the second connecting rod 12 sliding along the axial direction of the first connecting rod 11, ensuring smooth and unhindered transmission. This design avoids the use of complex structures such as universal hinges, reducing manufacturing costs while ensuring transmission reliability.

[0057] In terms of speed regulation, the first sprocket 5 is composed of several arc-shaped teeth 6. Each arc-shaped tooth 6 has teeth machined on its outer arc surface to mesh with the chain 19. All the arc-shaped teeth 6 are evenly distributed circumferentially on the turntable 4, forming a complete sprocket with a continuously adjustable pitch circle diameter. When it is necessary to change the oscillation frequency of the injection pipe 2, the pitch circle diameter of the first sprocket 5 is changed by driving several arc-shaped teeth 6 to slide synchronously along the radial direction of the turntable 4, thereby changing the transmission ratio between the first sprocket 5 and the second sprocket 18. This continuously variable diameter sprocket structure allows the oscillation frequency of the injection pipe 2 to be continuously adjusted online without stopping the machine to change gears, with fast response speed and high adjustment accuracy.

[0058] The tensioning assembly performs automatic tensioning during speed change: when the diameter of the first sprocket 5 changes, the effective length required for the chain 19 changes accordingly. The elastic torque provided by the torsion spring 25 causes the support plate 23 to swing towards the chain 19 at all times, and the third sprocket 20 automatically adjusts its position under the drive of the torsion spring 25, so that the chain 19 always maintains appropriate tension, avoiding the chain 19 from being too loose and slipping teeth or too tight and overloaded.

[0059] It should be added that: since the cam 14 and the lifting seat 9 are in sliding contact and operate in a high-temperature radiation environment, the contact surface between the two can be overlaid with a layer of hard alloy using plasma spraying process, which has excellent wear resistance and high-temperature oxidation resistance.

[0060] Example 3, please refer to Figures 1-8 The first transmission assembly includes a first slide rod 30 slidably mounted on the rotating drum 27, a connecting ring 31 fixedly mounted on the first slide rod 30, a plurality of second connecting seats 32 fixedly mounted on the connecting ring 31, and a plurality of third connecting seats 33 fixedly mounted on each of the plurality of sliders 29.

[0061] The first transmission assembly also includes a plurality of third connecting rods 34, one end of which is movably hinged to a plurality of second connecting seats 32 via hinge shafts, and the other end of which is movably hinged to a plurality of third connecting seats 33 via hinge shafts.

[0062] The second transmission assembly includes two second slide rods 36 symmetrically slidably mounted on the fifth rotating shaft 35 of the impeller 3. Both second slide rods 36 are elastically connected to the fifth rotating shaft 35 by springs 37. A fourth connecting rod 38 is slidably mounted on the third mounting base 26, and the first slide rod 30 is rotatably connected to the fourth connecting rod 38.

[0063] A rotating rod 39 is also rotatably mounted on the fourth connecting rod 38. The second transmission assembly also includes two fifth connecting rods 40. One end of each of the two fifth connecting rods 40 is movably hinged to the two second sliding rods 36 via hinge pins, and the other end of each of the two fifth connecting rods 40 is movably hinged to the rotating rod 39 via hinge pins.

[0064] In this embodiment, the regulating mechanism of the pressure control device for preparing fused silica products by high-temperature melting and casting realizes automatic negative feedback regulation of the oscillation frequency based on the discharge speed. Its specific working process is as follows.

[0065] When molten quartz flows through the injection pipe 2, it drives the impeller 3 to rotate. The rotational speed of the impeller 3 is positively correlated with the discharge velocity of the molten quartz. When the discharge rate of the upstream melting furnace increases or the back pressure of the mold decreases, the discharge velocity in the injection pipe 2 increases accordingly, and the rotational speed of the impeller 3 increases accordingly. Conversely, it decreases.

[0066] The rotation of impeller 3 drives the fifth shaft 35 to rotate synchronously. Under the action of centrifugal force, the two second slide rods 36 overcome the elastic force of spring 37 and slide radially outward along the fifth shaft 35. According to the principle of physics, centrifugal force is proportional to the square of the rotational speed. Therefore, when the discharge speed, i.e., the rotational speed of impeller 3, changes slightly, the change in centrifugal force on the second slide rods 36 will be amplified squarely, thus giving the adjustment mechanism high sensitivity. Even small fluctuations in discharge speed can be effectively sensed and triggered to adjust the action. Spring 37 provides a restoring force during this process, so that when the discharge speed decreases, the second slide rods 36 can reliably return radially inward, ensuring the bidirectional response capability of the adjustment mechanism.

[0067] The radial sliding of the two second slide rods 36, through the transmission of the two fifth connecting rods 40, drives the rotating rod 39 and the fourth connecting rod 38 to move axially. The first slide rod 30 moves synchronously with the fourth connecting rod 38, and through the transmission of the connecting ring 31 and several third connecting rods 34, drives all the sliders 29 to slide synchronously along their respective corresponding grooves 28, thereby controlling the synchronous extension and retraction of the arc-shaped toothed part 6 along the radial direction of the turntable 4.

[0068] When the discharge speed increases, the first slide bar 30 moves axially in the positive direction, causing all the arc-shaped teeth 6 to slide radially outward synchronously through the aforementioned transmission path, thus increasing the pitch circle diameter of the first sprocket 5. At this time, since the output speed of the motor 15 is constant, the angular velocity of the first sprocket 5 is inversely proportional to its pitch circle diameter. Therefore, the angular velocity of the first sprocket 5 decreases, and the speed transmitted to the cam 14 via the first rotating shaft 13 and the rotating drum 27 decreases synchronously, resulting in a corresponding decrease in the oscillation frequency of the injection pipe 2. After the oscillation frequency decreases, the alternating shear stress applied to the melt by the injection pipe 2 weakens, the apparent viscosity of the melt increases, the flow resistance increases, and the discharge speed is suppressed. This constitutes a negative feedback closed loop of "increased discharge speed → decreased oscillation frequency → decreased discharge speed".

[0069] Conversely, when the discharge speed decreases, the above process proceeds in reverse: the impeller 3 speed decreases, the second slide bar 36 slides radially inward under the action of the spring 37, the fourth connecting rod 38 and the first slide bar 30 move in opposite directions, the arc-shaped toothed part 6 contracts radially inward, the diameter of the first sprocket 5 decreases, the speed of the first rotating shaft 13 increases, the oscillation frequency of the injection pipe 2 increases, the melt is subjected to enhanced shearing action and its viscosity decreases, and the discharge speed rebounds.

[0070] Through the aforementioned negative feedback mechanism, the melt pressure and discharge rate within the injection pipe 2 are automatically maintained within the set process window. This purely physical feedback method based on mechanical transmission eliminates the need for electronic sensors and controllers, avoiding the drawbacks of electronic component failure under high-temperature environments. It boasts significant advantages such as fast response speed, high reliability, and maintenance-free operation, making it particularly suitable for harsh working conditions involving high temperatures and high dust levels during the preparation of fused silica products.

[0071] It should be noted that spring 37 is made of nickel-based high-temperature alloy wire, which is resistant to high temperatures.

[0072] Multiple sealing lines, such as a flexible expanded graphite filler layer, can be installed at the shaft hole where the fifth rotating shaft 35 protrudes from the wall of the injection pipe 2.

[0073] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0074] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A pressure control device for preparing fused silica products by high-temperature melting and casting, comprising a base (1), characterized in that: A material injection pipe (2) is rotatably mounted on the base (1), and a vibration pressure reduction mechanism, a drive mechanism and an adjustment mechanism are also provided on the base (1); The vibration pressure reducing mechanism is used to drive the injection pipe (2) to reciprocate based on the axis to form a shearing force on the melt. The driving mechanism is used to drive the vibration pressure reducing mechanism to run. The adjusting mechanism is used to adjust the reciprocating oscillation frequency of the injection pipe (2) according to the discharge speed of the quartz melt. The adjustment mechanism includes an impeller (3) rotatably installed in the injection pipe (2), the impeller (3) being driven to rotate by the quartz melt; The driving mechanism includes a turntable (4) rotatably mounted on the base (1), and a first sprocket (5) is provided on the turntable (4). The first sprocket (5) includes a plurality of arc-shaped teeth (6) slidably mounted on the turntable (4), and the plurality of arc-shaped teeth (6) form a complete sprocket.

2. The pressure control device for preparing fused silica products by high-temperature melting and casting according to claim 1, characterized in that: The adjustment mechanism further includes a first transmission component and a second transmission component; When the speed of the impeller (3) increases, the transmission of the second transmission component and the first transmission component drives several arc-shaped teeth (6) to slide outward along the radial direction of the turntable (4) to increase the diameter of the first sprocket (5), thereby reducing the speed of the turntable (4) and reducing the oscillation frequency of the injection pipe (2). When the speed of the impeller (3) decreases, the transmission of the second transmission component and the first transmission component drives several of the arc-shaped teeth (6) to slide inward along the radial direction of the turntable (4) to reduce the diameter of the first sprocket (5), thereby increasing the speed of the turntable (4) and increasing the oscillation frequency of the injection pipe (2).

3. The pressure control device for preparing fused silica products by high-temperature melting and casting according to claim 2, characterized in that: Two shock-absorbing brackets (7) are fixedly installed on the base (1), and the injection pipe (2) is rotatably installed on the two shock-absorbing brackets (7); The vibration pressure reduction mechanism includes two first mounting seats (8) fixedly installed on the base (1). The two first mounting seats (8) are symmetrically distributed based on the injection pipe (2). A lifting seat (9) is slidably installed on each of the two first mounting seats (8). A first connecting seat (10) is fixedly installed on each of the two lifting seats (9). Two first connecting rods (11) are fixedly installed on the injection pipe (2), and two second connecting rods (12) are slidably installed on each of the two first connecting rods (11). The two second connecting rods (12) are respectively hinged to the two first connecting seats (10) through hinge shafts. The vibration pressure reduction mechanism also includes a first rotating shaft (13) rotatably mounted on the base (1). Two cams (14) are fixedly mounted on the first rotating shaft (13). The two cams (14) are slidably connected to the two lifting seats (9) respectively, and the two cams (14) are installed in opposite directions. The two lifting seats (9) perform reciprocating lifting movements with the same frequency and opposite directions to drive the injection pipe (2) to swing back and forth based on the axis.

4. The pressure control device for preparing fused silica products by high-temperature melting and casting according to claim 3, characterized in that: The drive mechanism also includes a motor (15) fixedly mounted on the base (1). The output shaft of the motor (15) is fixedly connected to a second rotating shaft (17) via a reducer (16). A second sprocket (18) is fixedly mounted on the second rotating shaft (17). The first sprocket (5) and the second sprocket (18) are connected by a chain (19).

5. The pressure control device for preparing fused silica products by high-temperature melting and casting according to claim 4, characterized in that: The drive mechanism further includes a tensioning component, which includes a third sprocket (20) rotatably mounted on the base (1) and meshing with the chain (19); A second mounting base (21) is fixedly installed on the base (1), a third rotating shaft (22) is rotatably installed on the second mounting base (21), a support plate (23) is fixedly installed on the third rotating shaft (22), a fourth rotating shaft (24) is rotatably installed on the support plate (23), and a third sprocket (20) is fixedly installed on the fourth rotating shaft (24). The tensioning assembly also includes a torsion spring (25), the two ends of which are fixedly connected to the second mounting base (21) and the support plate (23), respectively.

6. The pressure control device for preparing fused silica products by high-temperature melting and casting according to claim 4, characterized in that: The vibration reduction mechanism further includes a third mounting base (26) fixedly installed on the base (1), a rotating cylinder (27) is rotatably installed on the third mounting base (26), the first rotating shaft (13) is fixedly installed on the rotating cylinder (27), and the turntable (4) is fixedly installed on the first rotating shaft (13).

7. The pressure control device for preparing fused silica products by high-temperature melting and casting according to claim 6, characterized in that: The turntable (4) has several grooves (28) arranged in a circular pattern. Each of the several arc-shaped teeth (6) has a slider (29) fixedly installed on it. The sliders (29) are slidably connected in the grooves (28). The rotation speed of the turntable (4) is adjusted by adjusting the transmission ratio between the second sprocket (18) and the first sprocket (5).

8. The pressure control device for preparing fused silica products by high-temperature melting and casting according to claim 7, characterized in that: The first transmission assembly includes a first slide rod (30) slidably mounted on the rotating drum (27), a connecting ring (31) fixedly mounted on the first slide rod (30), a plurality of second connecting seats (32) fixedly mounted on the connecting ring (31), and a plurality of third connecting seats (33) fixedly mounted on each of the plurality of sliders (29). The first transmission assembly further includes a plurality of third connecting rods (34), one end of each of the plurality of third connecting rods (34) is movably hinged to a plurality of second connecting seats (32) via hinge shafts, and the other end of each of the plurality of third connecting rods (34) is movably hinged to a plurality of third connecting seats (33) via hinge shafts.

9. The pressure control device for preparing fused silica products by high-temperature melting and casting according to claim 8, characterized in that: The second transmission assembly includes two second slide rods (36) symmetrically slidably mounted on the fifth rotating shaft (35) of the impeller (3). Both second slide rods (36) are elastically connected to the fifth rotating shaft (35) by springs (37). A fourth connecting rod (38) is slidably mounted on the third mounting base (26). The first slide rod (30) is rotatably connected to the fourth connecting rod (38).

10. The pressure control device for preparing fused silica products by high-temperature melting and casting according to claim 9, characterized in that: The fourth connecting rod (38) is also rotatably mounted with a rotating rod (39). The second transmission assembly also includes two fifth connecting rods (40). One end of each of the two fifth connecting rods (40) is movably hinged to the two second sliding rods (36) via a hinge shaft, and the other end of each of the two fifth connecting rods (40) is movably hinged to the rotating rod (39) via a hinge shaft.

Images