Insulation structure and crystal growth furnace

Abstract

The present application relates to a heat preservation structure and a crystal growth furnace, including: a body, wherein the body has a heat preservation cavity inside, the top of the body has a top heat preservation layer, and the top heat preservation layer is provided with a channel allowing the lifting shaft to pass through the heat preservation cavity; the channel includes: a first space, the first space is located at the center of the channel, and the first space is used to accommodate the lifting shaft; a second space, the second space is connected to the first space, the second space is annular and arranged around the circumference of the first space, and the second space is used to provide a space for movement when the lifting shaft swings. The technical problem of the heat preservation structure and the lifting shaft colliding is solved, and the technical effect of preventing the lifting shaft from colliding with the heat preservation structure is improved.

Description

Technical Field

[0001] The present application relates to the field of crystal growth, and in particular to a thermal insulation structure and a crystal growth furnace. Background Art

[0002] In a crystal growth furnace, the insulation structure is used to maintain the temperature stability of the thermal field in the furnace and participates in the formation of the thermal field in the furnace. The morphology, growth rate, and growth quality of crystals such as sapphire crystals and silicon carbide crystals are extremely dependent on the thermal field. If the thermal field is stable, the growth quality of the crystal is high; if the thermal field is unstable, various defects are likely to occur during the growth process, resulting in low growth quality of the crystal. In severe cases, metamorphism may occur, resulting in the inability to grow crystals. In particular, the growth time of large-diameter single crystals is relatively long. When growing large-diameter single crystals, the insulation structure is used to strengthen the insulation of the low-temperature zone in the thermal field, which plays an extremely important role in ensuring that the crystal does not crack, maintaining the growth interface temperature, and ensuring local nucleation and crystallization in the melt.

[0003] In the prior art, sapphire furnaces usually use a hard-shaft pulling method to pull crystals. A channel is provided on the top of the insulation layer to allow the pulling shaft to pass through. The channel is designed to be smaller in order to improve the insulation performance of the overall insulation structure, prevent internal impurities from overflowing, or prevent external impurities from entering. However, due to machining accuracy factors, it is often difficult to align the pulling shaft concentrically everywhere, and the pulling shaft is relatively long, resulting in a larger cumulative error, which may cause eccentric shaking of the pulling shaft during rotation, thereby colliding with the insulation layer and causing damage to the insulation material.

[0004] Therefore, the technical problem of the prior art is that the thermal insulation structure needs to be improved urgently. Summary of the invention

[0005] The present application provides a thermal insulation structure and a crystal growth furnace, which solves the technical problem of collision between the thermal insulation structure and the pulling shaft, thereby achieving the technical effect of improving the prevention of collision between the pulling shaft and the thermal insulation structure.

[0006] On the one hand, the present application provides a thermal insulation structure, which adopts the following technical solution:

[0007] A thermal insulation structure comprises: a main body, wherein a thermal insulation cavity is provided inside the main body, a top thermal insulation layer is provided on the top of the main body, a channel is provided on the top thermal insulation layer for allowing a lifting shaft to pass through the thermal insulation cavity; the channel comprises: a first space, wherein the first space is located at the center of the channel, and the first space is used to accommodate the lifting shaft; a second space, wherein the second space is connected to the first space, the second space is annular and is arranged around the circumference of the first space, and the second space is used to provide a movable space when the lifting shaft is shaken.

[0008] Preferably, it further comprises: a cover assembly, wherein the cover assembly comprises a cover, wherein the cover is located outside the insulation cavity, and wherein the cover is movably connected to the top insulation layer so that the cover can at least partially cover the second space of the channel.

[0009] Preferably, the cover body includes a plurality of assemblies, which are arranged around the axis of the channel, and the assemblies are slidably connected to the top insulation layer, so that the assemblies form at least a first state and a second state: in the first state, the assemblies are spliced ​​to form the annular cover body, and the cover body is concentric, coaxial or basically coaxial with the channel so that the cover body at least partially covers the second space of the channel; in the second state, the assembly slides to the side of the channel to open the second space of the channel.

[0010] Preferably, the cover assembly further comprises a first driving member, the number of which is the same as the number of the assemblies and they correspond one to one, and the first driving member is connected to and acts on the assemblies to drive the assemblies to slide.

[0011] Preferably, the cover body comprises a plurality of assemblies, which are arranged around the axis of the channel, and the assemblies are rotatably connected to the top insulation layer, so that the assemblies form at least a first state and a second state: in the first state, the assemblies are spliced ​​to form the annular cover body, and the cover body is concentric, coaxial or substantially coaxial with the channel so that the cover body at least partially covers the second space of the channel; in the second state, the assembly is rotated to the side of the channel to open the second space of the channel.

[0012] Preferably, the cover assembly also includes a second driving member, the number of which is the same as the number of the assemblies and they correspond one to one, the second driving member is used to drive the assembly to rotate, the second driving member includes: a base, the base is located on the side of the assembly, the base is fixedly connected to the top insulation layer; a nozzle, the nozzle is connected to the base and acts on the assembly to pneumatically drive the assembly to rotate; and a spring, the spring is connected between the base and the assembly, the spring is used to reset the assembly.

[0013] Preferably, the assembly has an extension portion, which is used to cooperate with the nozzle so that the assembly rotates under the pneumatic action of the nozzle; the extension portion has a reflux portion, and a force-bearing area is formed between the reflux portion and the extension portion.

[0014] Preferably, an air duct is provided inside the assembly, and the air duct has an air inlet and an air outlet, the air inlet is provided on the force-bearing area, and the air outlet is provided on the side of the assembly close to the channel when the assembly is in the second state, so that when the nozzle acts on the force-bearing area, the airflow can be output through the air inlet and output through the air outlet to act on the first space and the second space.

[0015] Preferably, the air outlet is arranged to be inclined toward the inside of the heat preservation cavity so that the airflow enters the heat preservation cavity downward.

[0016] On the other hand, the crystal growth furnace provided in the present application adopts the following technical solution:

[0017] A crystal growth furnace has the thermal insulation structure.

[0018] In summary, the present application includes at least one of the following beneficial technical effects:

[0019] The present application sets up a channel in the insulation structure, which allows the lifting shaft to accommodate the lifting shaft when it shakes, that is, when the lifting shaft shakes or slightly displaces, it can enter this space, thereby increasing the flexibility and fault tolerance of the structure and preventing the lifting shaft from colliding with the insulation structure when shaking. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the thermal insulation structure in the prior art;

[0021] Figure 2 It is a schematic diagram of a heat preservation structure and a lifting shaft in the prior art;

[0022] Figure 3 is a schematic diagram of a channel of the thermal insulation structure described in the present application;

[0023] Figure 4 It is a schematic diagram of the heat preservation structure and the lifting shaft described in this application;

[0024] Figure 5 is a schematic diagram of a cover assembly of the thermal insulation structure described in the present application;

[0025] Figure 6 is a schematic diagram of the thermal insulation structure described in the present application;

[0026] Figure 7 is a top view of the thermal insulation structure described in the present application;

[0027] Figure 8 It is a schematic diagram of the assembly of the cover assembly in the thermal insulation structure described in the present application;

[0028] Fig. 9is a schematic diagram of a first assembly of a cover assembly in the thermal insulation structure described in the present application in a first state;

[0029] Fig.10 is a schematic diagram of a first assembly of a cover assembly in the thermal insulation structure described in the present application in a second state;

[0030] Fig.11 is a schematic diagram of a second assembly of the cover assembly in the thermal insulation structure described in the present application in a first state;

[0031] Fig.12 is a schematic diagram of a second assembly of the cover assembly in the thermal insulation structure described in the present application in a second state;

[0032] Fig.13 It is a side view of a second assembly of the cover assembly in the thermal insulation structure described in the present application;

[0033] Fig.14 It is a schematic diagram of a second assembly of the cover assembly and a second driving member in the thermal insulation structure described in the present application;

[0034] Fig.15 It is a schematic diagram of a first air outlet of a second assembly of a cover assembly in the thermal insulation structure described in the present application;

[0035] Fig.16 It is a schematic diagram of a second air outlet of a second assembly of a cover assembly in the thermal insulation structure described in the present application;

[0036] Fig.17 is a schematic diagram of the growth furnace described in this application.

[0037] Explanation of the reference numerals: 110, lifting shaft; 120, growth furnace; 200, main body; 210, insulation chamber; 220, top insulation layer; 300, passage; 310, first space; 320, second space; 400, cover assembly; 410, cover; 411, assembly; 4111, extension portion; 4112, reflux portion; 4113, force-bearing area; 4114, airway; 4115, air inlet; 4116, air outlet; 4117, track; 4118, rotating shaft; 420, first driving member; 430, second driving member; 431, base; 432, nozzle; 433, spring. DETAILED DESCRIPTION

[0038] The serial numbers assigned to the components herein, such as "first", "second", etc., are only used to distinguish the objects described and do not have any order or technical meaning. The "connection" and "coupling" mentioned in this application, unless otherwise specified, include direct and indirect connections (couplings). In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0039] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0040] The embodiment of the present application provides a heat preservation structure and a crystal growth furnace 120, which solves the technical problem of collision between the heat preservation structure and the pulling shaft 110, thereby achieving the technical effect of improving the prevention of collision between the pulling shaft 110 and the heat preservation structure.

[0041] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods. It should be understood that the specific embodiments described here are only used to explain the present application and are not used to limit the present application.

[0042] Sapphire crystal pulling is an advanced crystal growth technology, and its principle is mainly based on the melting method. In a specific growth furnace 120, the sapphire raw material is heated to a molten state, and then the molten sapphire is slowly formed into crystals through a precisely controlled pulling process. In this process, the stability of the pulling shaft 110 is crucial, which determines the growth quality and uniformity of the crystal. At the same time, in the crystal growth furnace 120, the insulation structure plays an important role in maintaining the temperature stability of the thermal field in the furnace. It participates in the formation of the thermal field in the furnace and has a decisive influence on the morphology, growth rate and growth quality of the crystal. The growth of high-quality crystals such as sapphire crystals and silicon carbide crystals is particularly dependent on a stable and uniform thermal field environment. If the thermal field is stable, the crystal growth quality is high. Otherwise, it may lead to an increase in crystal defects and a decrease in growth quality. In severe cases, it may even cause metamorphism, resulting in crystal growth failure. For the growth of large-diameter single crystals, due to its long growth cycle, the stability requirements of the thermal field are more stringent. The insulation structure plays a key role in strengthening the insulation of the low temperature zone in the thermal field, which helps to prevent crystal cracking, maintain the stability of the growth interface temperature, and ensure the smooth local nucleation and crystallization of the melt.

[0043] like Figure 1 , Figure 2 As shown, the shaking phenomenon during the pulling process is a factor that needs to be strictly controlled in sapphire crystal pulling. The ideal pulling process should remain stable to avoid any unnecessary vibration or shaking. However, in the prior art, due to the machining accuracy limitation of the sapphire pulling shaft 110 (hard shaft) and the cumulative error of the length of the pulling shaft 110, the pulling shaft 110 is prone to eccentric shaking during rotation. In addition, the shaking of the pulling shaft 110 may be further aggravated by factors such as mechanical vibration, unstable motor drive or external interference during the pulling process.

[0044] This shaking not only affects the accuracy and stability of the lifting shaft 110, but also increases the risk of collision between the lifting shaft 110 and the insulation layer. As an important part of the growth furnace 120, the insulation layer is used to maintain the temperature stability in the furnace to ensure the normal growth of the sapphire crystal. Once the lifting shaft 110 collides with the insulation layer, it will not only destroy the integrity of the insulation layer and reduce its thermal insulation effect, but may also cause temperature fluctuations in the furnace, which will seriously affect the growth quality and stability of the sapphire crystal.

[0045] However, sapphire furnaces generally use a hard-shaft pulling method for crystal pulling. In order to improve the overall thermal insulation performance of the insulation structure and prevent internal impurities from overflowing or external impurities from entering, the channel 300 at the top of the insulation layer is designed to be relatively small. However, this design faces challenges brought by machining accuracy: it is often difficult to achieve concentricity everywhere for the pulling shaft 110, and because the length of the pulling shaft 110 is relatively long, the cumulative error is further increased, causing the pulling shaft 110 to eccentrically shake during rotation, and then collide with the insulation layer. This collision will not only cause damage to the insulation material and affect the insulation performance, but may also cause irreversible damage to the growth of the crystal, such as crystal cracks, temperature fluctuations at the growth interface, etc., which seriously reduce the growth quality and success rate of the crystal.

[0046] During the crystal growth process, crystal shaking is a phenomenon that needs to be carefully controlled, although it can be compensated and adjusted to a certain extent by technical means to continue the crystal pulling process. However, when the pulling shaft 110 collides with the insulation layer, the problem becomes particularly serious.

[0047] The collision will not only cause the shaking of the lifting shaft 110 to intensify, but more importantly, it will cause serious disorder of the thermal field inside the insulation layer. As a key component to maintain the stability of the thermal field in the furnace, the uniformity and stability of the internal thermal field of the insulation layer have a crucial impact on the growth quality of the crystal. Once the thermal field is damaged, the growth environment of the crystal will change drastically, which may lead to uneven crystal growth rate, increased internal stress of the crystal, an increase in crystal defects, and even serious problems such as crystal cracking and out-of-control growth interface temperature. What is more serious is that the damage of the insulation layer may also cause external impurities to enter the furnace, further polluting the crystal growth environment and increasing the uncertainty of crystal growth. In extreme cases, the collision may cause the lifting shaft 110 to be unable to continue to work normally, and the crystal growth process is forced to be interrupted, resulting in a huge waste of materials and time.

[0048] Therefore, during the sapphire crystal pulling process, how to effectively control the shaking of the pulling shaft 110 to avoid collision with the insulation layer has become a technical problem that needs to be solved urgently.

[0049] This application proposes a thermal insulation structure, such as Figure 3-Figure 5 As shown, it can be applied to the case where the lifting shaft 110 shakes to prevent the lifting shaft 110 from colliding with the insulation layer. The insulation structure includes a body 200 and a cover assembly 400. The body 200 is used as the main insulation structure inside the sapphire furnace. The body has an insulation chamber 210 inside. The sapphire raw material is located in a crucible in the insulation chamber 210 to complete crystal growth and is lifted by the lifting shaft 110. The cover assembly 400 is arranged on the top of the body to cover the top of the insulation layer to improve the performance of the insulation structure.

[0050] Subject, such as Figure 6 , Figure 7 As shown, it is arranged in the form of a cylinder on the periphery of the crucible, as the main part of the insulation structure, and is a key component in the sapphire crystal growth furnace 120. Generally, the main body adopts insulation materials such as carbon felt; the interior of the main body is provided with an insulation chamber 210, which is used to insulate the crucible, i.e., the sapphire crystal growth environment, to ensure normal sapphire crystal growth; the top of the main body is provided with a circular top insulation layer 220, and a channel 300 is provided on the top insulation layer 220, and the channel 300 is used to cooperate with the pulling shaft 110 to allow the pulling shaft 110 to pass through the insulation layer and enter the crucible; it can be understood that the pulling shaft carries a seed crystal, and the pulling shaft 110 extends from the outside of the crystal growth furnace 120, passes through the insulation layer and then enters the crucible, the seed crystal and the molten sapphire raw material contact point crystal, and through process control, the crystal gradually grows on the seed crystal.

[0051] Further, such as Figure 6 , Figure 7 As shown, the channel 300 includes a first space 310 and a second space 320. The first space 310 is located at the center of the channel 300, and the first space 310 is used to accommodate the lifting shaft 110. The second space 320 is connected to the first space 310, and the second space 320 is arranged in a ring shape on the surrounding side of the first space 310. The second space 320 is used to provide a moving space for the lifting shaft 110 when it is shaken.

[0052] Specifically, a first space 310 is provided at the center of the channel 300, and the first space 310 is used to accommodate the lifting shaft 110; when the lifting shaft 110 is in normal working condition, it is stably located in this space, ensuring the smooth progress of the crystal growth process; the first space 310 not only ensures the stability of the lifting shaft 110, but also avoids direct contact with the insulation layer, thereby reducing heat loss.

[0053] The second space 320 is closely connected with the first space 310, or in other words, the second space 320 and the first space 310 are connected everywhere, that is, the second space 320 and the first space 310 are in the same space, and the first space 310 and the second space 320 are defined only for division; the second space 320 is annular in structure and is arranged around the first space 310; the main function of the second space 320 is to provide adjustment space for the lifting shaft 110; in actual operation, since the lifting shaft 110 may shake due to various reasons (such as processing accuracy, mechanical vibration, etc.), the lifting shaft 110 can enter the second space 320 for slight displacement adjustment, which not only effectively avoids the problem of damage to the insulation layer caused by the collision between the lifting shaft 110 and the insulation layer, but also ensures the stability of the lifting shaft 110 during the shaking process; it is crucial for the growth of crystals, and it can ensure that the crystals will not be disturbed by any external factors during the growth process, thereby ensuring the high-quality growth of crystals.

[0054] The cover assembly 400, such as Figure 8 As shown, the cover assembly 400 is used to cover the channel 300 so that the channel 300 can be opened or closed. The cover assembly 400 is arranged outside the heat preservation chamber 210. The cover assembly 400 includes a cover 410. The cover 410 is located outside the heat preservation chamber 210 and is movably connected to the top heat preservation layer 220, so that the cover 410 can be movably covered on the channel 300. Since the first space 310 is used to accommodate the lifting shaft 110, the cover 410 mainly covers the second space 320 to cover the channel 300, so as to improve the overall performance of the heat preservation structure. Further, the cover 410 includes a plurality of assemblies 411, which are independent of each other and each assembly 411 is movably connected to the top heat preservation layer 220.

[0055] In one embodiment, Fig. 9 , Fig.10 As shown, there are six assemblies 411, which are arranged around the axis of the channel 300 and are fan-shaped. More specifically, the shape of the assembly 411 is a circular ring segment similar to a fan, so that multiple assemblies 411 can be spliced ​​to form a ring. The assembly 411 is slidably connected to the top insulation layer 220 through the track 4117. Specifically, each assembly 411 has a degree of freedom of movement along the direction of the diameter of the top insulation layer 220, so that each assembly 411 can move closer to the axis of the insulation structure or move away from the outside of the insulation structure. By driving the movement of each assembly 411, the assembly 411 forms a first state and a second state:

[0056] like Fig. 9 As shown, in the first state, the assembly 411 moves to the innermost side toward the axial direction of the heat preservation structure, and a plurality of assemblies 411 are spliced ​​to form an annular cover 410, and the cover 410 and the channel 300 are kept concentric and coaxial or substantially concentric and coaxial. In this way, the annular cover 410 formed by the assembly 411 can cover the second space 320 of the channel 300, thereby achieving the closure and heat preservation of the channel 300. It can be understood that the assembly 411 is suitable for the lifting shaft 110 to be in the first state without shaking or before shaking; wherein, substantially concentric and coaxial means that there may be a certain error in the concentric and coaxial, and the error is less than 10%;

[0057] like Fig.10As shown, in the second state, the assembly 411 moves to the outermost side away from the axis of the heat preservation structure, that is, the assembly 411 can slide to the side of the channel 300, thereby opening the second space 320. In this way, the second space 320 of the channel 300 can be flexibly opened or closed as needed, which provides convenience for the operation and maintenance of the lifting shaft 110. It can be understood that when the assembly 411 is in the second installation, it is suitable for the lifting shaft 110 to shake, and the assembly 411 avoids the shaking lifting shaft 110 to prevent the lifting shaft 110 from colliding with the heat preservation structure.

[0058] Further, such as Fig. 9 , Fig.10 As shown, the cover body assembly 400 also includes a first driving member 420, which is used to drive the above-mentioned slidable assembly 411 to move linearly. The number of the first driving members 420 is the same as the number of the assemblies 411, and the first driving members 420 and the assemblies 411 correspond one to one, that is, each first driving member 420 is used to drive an assembly 411; illustratively, considering the high ambient temperature, the first driving member 420 needs to be resistant to high temperature. Therefore, the first driving member 420 can be selected as a linear drive such as a linear motor, hydraulic cylinder or electric cylinder that can withstand high temperature.

[0059] In the second embodiment, if Fig.11 , Fig.12 As shown, there are six assemblies 411, which are arranged around the axis of the channel 300 and are fan-shaped. More specifically, the shape of the assembly 411 is a circular ring segment similar to a fan, so that multiple assemblies 411 can be spliced ​​to form a ring. The assembly 411 is rotatably connected to the top insulation layer 220 via a rotating shaft 4118. Specifically, each assembly 411 has a rotational freedom around the rotating shaft 4118, so that each assembly 411 can rotate toward the axis of the insulation structure or rotate away from the outside of the insulation structure. By driving the rotation of each assembly 411, the assembly 411 forms a first state and a second state:

[0060] like Fig.11 As shown, in the first state, the assembly 411 is spliced ​​to form an annular cover 410, and the cover 410 and the channel 300 are kept concentric and coaxial or substantially concentric and coaxial. In this way, the annular cover 410 formed by the assembly 411 can cover the second space 320 of the channel 300, thereby achieving the closure and heat preservation of the channel 300. It can be understood that the assembly 411 is suitable for the lifting shaft 110 to be in the first state without shaking or before shaking; wherein, substantially concentric and coaxial means that there may be a certain error in the concentric and coaxial, and the error is less than 10%;

[0061] like Fig.12As shown, in the second state, the assembly 411 rotates to the outermost side in the direction away from the axis of the heat preservation structure, that is, the assembly rotates to the side of the channel 300, thereby opening the second space 320. In this way, the second space 320 of the channel 300 can be flexibly opened or closed as needed, which provides convenience for the operation and maintenance of the lifting shaft 110. It can be understood that when the assembly 411 is in the second installation, it is suitable for the lifting shaft 110 to shake, and the assembly 411 avoids the shaking lifting shaft 110 to prevent the lifting shaft 110 from colliding with the heat preservation structure.

[0062] It should be noted that if Fig.13 As shown, when the assembly 411 is arranged to rotate and the number of assemblies 411 is large, the assembly 411 is arranged in a wedge shape and can at least partially overlap with adjacent assemblies 411 during rotation to prevent interference between the assemblies 411 during rotation.

[0063] Further, such as Fig.14 As shown, the cover assembly 400 also includes a second driving member 430, which is used to drive the above-mentioned rotatable assembly 411 to rotate. The number of second driving members 430 is the same as the number of assemblies 411, and the second driving members 430 and assemblies 411 correspond one to one, that is, each second driving member 430 is used to drive one assembly 411.

[0064] Specifically, the second driving member 430 is used to drive the assembly 411 to rotate, thereby changing the state of the cover body 410, and each assembly 411 is equipped with a corresponding second driving member 430; each second driving member 430 includes a base 431, a nozzle 432 and a spring 433, and the base 431 is used as an installation base to provide stable support for the nozzle 432 and the spring 433; the nozzle 432 is used to drive the assembly 411 to rotate; the spring 433 is used to reset the assembly 411.

[0065] Furthermore, the base 431 is located on the side of the assembly 411 and is fixedly connected to the top insulation layer 220; the nozzle 432 is connected to the base 431 and acts on the assembly 411, and the nozzle 432 can drive the assembly 411 to rotate pneumatically; it can be understood that the nozzle 432 is connected to an external high-pressure gas source, and the nozzle 432 is supplied with external gas to realize the jet of the nozzle 432; the spring 433 is connected between the base 431 and the assembly 411, and is used to help the assembly 411 to return to its initial position after the nozzle 432 stops acting; in other words, when the assembly 411 is pneumatically rotated to the second state by the nozzle 432, the nozzle 432 stops supplying air, and the assembly 411 in the second state can be pulled back and rotated back to the first state by the spring 433. The second driving member 430 enables the assembly 411 to rotate under the pneumatic action of the nozzle 432, thereby changing the state of the cover 410 (i.e., switching between the first state and the second state by changing the state of the assembly 411). When the nozzle 432 applies pneumatic force to the assembly 411, the assembly 411 rotates around the rotation axis 4118. At this time, the assembly 411 is in the first state, and a plurality of assemblies 411 are spliced ​​to form an annular cover 410, and the cover 410 and the channel 300 are kept concentric and coaxial or substantially concentric and coaxial. Shaft, in this way, the annular cover body 410 formed by splicing the assembly 411 can cover the second space 320 of the channel 300, thereby realizing the closure and insulation of the channel 300; when the nozzle 432 stops working, the spring 433 will help the assembly 411 to reset. At this time, the assembly 411 is in the second state, and the assembly 411 can slide to the side of the channel 300, thereby opening the second space 320. In this way, the second space 320 of the channel 300 can be flexibly opened or closed as needed, which provides convenience for the operation and maintenance of the lifting shaft 110.

[0066] Furthermore, if Fig.14As shown, each assembly 411 is provided with an extension portion 4111, and the extension portion 4111 is arranged in a direction away from the axis of the heat preservation structure. The extension portion 4111 is used to cooperate with the nozzle 432, so that the assembly 411 can rotate under the activation of the nozzle 432. The extension portion 4111 is also provided with a return portion 4112. In other words, the extension portion 4111 is also connected to the return portion 4112. The return portion 4112 and the extension portion 4111 are arranged obliquely, so that a force area 4113 is formed between the return portion 4112 and the extension portion 4111. The force area 4113 serves as the main area for the nozzle 432 to apply aerodynamic force. The inclined design of the confluence area prevents airflow from overflowing, thereby improving the airflow drive utilization rate. The extension portion 4111 and the return portion 4112 are interconnected to form a force area 4113, so that the assembly 411 can stably rotate under the pneumatic action of the nozzle 432. The existence of the force area 4113 ensures that the pneumatic force can effectively act on the assembly 411, thereby achieving the purpose of rotation.

[0067] Further, if Fig.14 , Fig.15 As shown, an air duct 4114 is provided inside the assembly 411, and the air duct 4114 has an air inlet 4115 and an air outlet 4116. The airflow of the assembly 411 is driven by the secondary nozzle 432 to blow air into the channel 300, thereby achieving the functions of heat preservation and insulation. The air inlet 4115 is arranged on the force-bearing area 4113, ensuring that the airflow of the nozzle 432 can directly act on the force-bearing area 4113 to drive the assembly 411 to rotate, and at the same time can reuse part of the airflow to enter the air inlet 4115; the air outlet 4116 is arranged on a side of the assembly 411 close to the channel 300 when the assembly 411 is in the second state. When multiple assemblies 411 are switched to the second state at the same time, part of the airflow ejected by each nozzle 432 will enter the corresponding assembly 411 and be output from the air outlet 4116. In other words, a plurality of assemblies 411 are arranged. When each assembly 411 is in the second state, the channel 300 (or the second space 320) is opened. Through the above arrangement, an all-round air film can be formed between the assembly 411 and the lifting shaft 110.

[0068] So, like Fig.14 , Fig.15As shown, when the assembly 411 is in the second state, the air outlet 4116 on the side facing (or close to) the channel 300 can output airflow to achieve airflow isolation from the second space 320 (or channel 300). On the one hand, the airflow can use an inert gas with good thermal insulation performance, and use the airflow to form an air film on the second space 320 (or channel 300), thereby improving the thermal insulation effect of the thermal insulation chamber 210. On the other hand, because it is determined that crystal shaking occurs, the assembly 411 is switched to the second state to avoid the lifting shaft 110. During the crystal shaking process, the airflow and temperature inside the crucible are turbulent, which can easily cause impurities in the crucible to float up and overflow the thermal insulation layer. In this way, the airflow is used to form an air film on the second space 320 (or channel 300), thereby isolating the impurities and preventing them from floating up. In one embodiment, as Fig.16 As shown, the air outlet 4116 is inclined toward the inside of the insulation chamber 210 so that the airflow enters the insulation chamber 210 downward. In other words, when the airflow enters and is output by the air outlet 4116, since the air outlet 4116 is inclined downward toward the inside of the insulation chamber 210, the airflow output direction is also changed to be inclined downward toward the insulation chamber 210, which can improve the insulation performance of the insulation structure. At the same time, the downward-inclined airflow can further prevent impurities from floating up. For impurities floating up, the downward-inclined airflow can sweep the impurities downward to prevent the impurities from overflowing.

[0069] The present application also provides a crystal growth furnace 120, in particular a sapphire crystal growth furnace 120, such as Fig.17 As shown, the above-mentioned insulation structure is suitable for crystal shaking scenes to prevent the lifting shaft 110 from shaking and colliding with the insulation layer. It can be understood that the assembly 411 and the first drive member 420 or the second drive member 430 act as an actuator. When crystal shaking is required (that is, when it is necessary to avoid the collision between the lifting shaft 110 and the insulation layer), the assembly 411 can be actively moved or rotated; further, a CCD camera can be set on the top of the crystal growth furnace 120. The CCD observes the shaking of the lifting shaft 110 through the window. When the shaking amplitude of the lifting shaft 110 reaches a threshold, the assembly 411 is automatically moved or rotated to avoid the shaking of the lifting shaft 110 and the collision with the insulation layer.

[0070] Working principle / steps:

[0071] The channel 300 provided on the top insulation layer 220 of the insulation structure is divided into a first space 310 and a second space 320. The first space 310 is used to accommodate the lifting shaft 110, and the second space 320 provides a movable space for the lifting shaft 110 when it shakes, so as to ensure the stable operation of the lifting shaft 110. Through the design of the cover assembly 400, the cover 410 can be movably connected to the top insulation layer 220 to cover or open the second space 320. The cover 410 is arranged around the axis of the channel 300 by a plurality of assemblies 411, and the assemblies 411 can be slidably or rotatably connected to the top insulation layer 220. In the first state, the assemblies 411 are spliced ​​to form an annular cover 410 to cover the second space 320; in the second state, the assemblies 411 slide or rotate to the side of the channel 300 to open the second space 320. The sliding or rotating driving mode can be realized by the first or second driving member 430, wherein the second driving member 430 pneumatically drives the assembly 411 to rotate through the combination of the base 431, the nozzle 432 and the spring 433, and realizes the reset with the help of the spring 433; the nozzle 432 acts on the force area 4113 on the extension 4111 of the assembly 411 to produce a rotating effect. The air channel 4114 inside the assembly 411 is designed so that when the nozzle 432 acts on the force area 4113, the airflow can enter the heat preservation chamber 210 through the air channel 4114, and the airflow can use an inert gas with good heat preservation performance, and use the airflow to form an air film on the second space 320 (or channel 300) to achieve heat preservation and insulation effects.

[0072] Technical effects:

[0073] The present application sets a channel 300 in the insulation structure, and the channel 300 allows the lifting shaft 110 to be accommodated when it is shaking, that is, when the lifting shaft 110 shakes or slightly displaces, it can enter this space, thereby increasing the flexibility and fault tolerance of the structure and preventing the lifting shaft 110 from colliding with the insulation structure when shaking.

[0074] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0075] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A thermal insulation structure, characterized in that: include: The main body has a heat preservation cavity inside, the top of the main body has a top heat preservation layer, and the top heat preservation layer has a channel allowing the lifting shaft to pass through and enter the heat preservation cavity; the channel includes: A first space, the first space is located at the center of the channel, and the first space is used to accommodate the lifting shaft; a second space, the second space being connected to the first space, the second space being annular and arranged around the circumference of the first space, and the second space being used to provide a movable space when the lifting shaft is shaken; Also includes: A cover assembly, the cover assembly comprising a cover, the cover is located outside the heat preservation cavity, the cover is movably connected to the top heat preservation layer, so that the cover can at least partially cover the second space of the channel; The cover body includes a plurality of assemblies, which are arranged around the axis of the channel, and the assemblies are rotatably connected to the top insulation layer, so that the assemblies form at least a first state and a second state: In the first state, the assembly is spliced ​​to form the annular cover, which is concentric and coaxial or substantially coaxial with the channel, so that the cover at least partially covers the second space of the channel; In the second state, the assembly rotates to the side of the channel to open the second space of the channel; The cover assembly further includes a second driving member, the number of which is the same as the number of the assembly members and they are matched one-to-one, the second driving member is used to drive the assembly members to rotate, and the second driving member includes: A base, the base is located at the side of the assembly, and the base is fixedly connected to the top insulation layer; a nozzle connected to the base and acting on the assembly to pneumatically drive the assembly to rotate; and A spring, the spring being connected between the base and the assembly, and the spring being used for resetting the assembly; The assembly has an extension portion, which is used to cooperate with the nozzle so that the assembly rotates under the pneumatic action of the nozzle; the extension portion has a return portion, and a force-bearing area is formed between the return portion and the extension portion; an air duct is arranged inside the assembly, and the air duct has an air inlet and an air outlet, the air inlet is arranged on the force-bearing area, and the air outlet is arranged on the side of the channel close to the assembly when the assembly is in the second state, so that when the nozzle acts on the force-bearing area, the airflow can be output through the air inlet and output through the air outlet to act on the first space and the second space.

2. A thermal insulation structure according to claim 1, characterized in that: The air outlet is arranged to be inclined toward the inside of the heat preservation cavity, so that the airflow enters the heat preservation cavity downward.

3. A crystal growth furnace, characterized in that: The invention has a heat-insulating structure as claimed in any one of claims 1 to 2.

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