Heat preservation device and crystal pulling system

Abstract

The embodiment of the utility model provides a heat preservation device and a crystal pulling system. The heat preservation device comprises a first heat preservation cylinder and a second heat preservation cylinder, wherein the first heat preservation cylinder is arranged outside the second heat preservation cylinder in a sleeving mode, and a gap is formed between the first heat preservation cylinder and the second heat preservation cylinder. According to the heat preservation device, a double-layer heat preservation structure can be formed, the effect of reflecting heat of the heater can be improved, heat loss in a thermal field environment can be reduced, energy consumption can be reduced, and the disassembly and assembly convenience of the heat preservation device can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of crystal pulling, in particular to a heat preservation device and a crystal pulling system. Background Art

[0002] The production of single crystal silicon rods is one of the important components of photovoltaic power generation. Reducing the energy consumption of single crystal silicon rods during the growth process is currently the key development direction of the industry.

[0003] In the prior art, during the growth of single crystal silicon rods, the radiation from the heater at high temperature directly heats the outer insulation material, and the temperature of the insulation material rises and radiates heat to the furnace wall and furnace bottom, and then the heat is taken away through the furnace cooling water system, causing heat loss. At present, in order to reduce heat loss, the thickness of the insulation tube is usually increased, however, increasing the thickness of the insulation tube makes it inconvenient to disassemble and assemble the thermal field. Utility Model Content

[0004] In view of the above problems, embodiments of the present utility model are proposed to provide a heat preservation device and a crystal pulling system that overcome the above problems or at least partially solve the above problems.

[0005] In order to solve the above problems, the embodiment of the utility model discloses a heat preservation device, comprising: a first heat preservation cylinder and a second heat preservation cylinder; wherein,

[0006] The first heat-insulating cylinder is sleeved outside the second heat-insulating cylinder, and a gap is provided between the first heat-insulating cylinder and the second heat-insulating cylinder, and at least a part of the gap constitutes a first channel.

[0007] In this embodiment, the first heat-insulating tube and the second heat-insulating tube can be combined to form a double-layer heat-insulating structure, which can improve the effect of heat reflection, reduce heat loss in the thermal field environment, and reduce energy consumption.

[0008] Optionally, the inner wall of the first heat-insulating cylinder and the outer wall of the second heat-insulating cylinder are enclosed to form a first channel;

[0009] A gas inlet is provided on the second heat-insulating cylinder, or the gas inlet is formed between the first heat-insulating cylinder and the second heat-insulating cylinder;

[0010] The gas inlet is in communication with the first channel.

[0011] In this embodiment, the gap between the first insulation tube and the second insulation tube can form a first channel, which can eliminate the bottom exhaust hole, reduce energy consumption, and reduce the carbon in the gas from entering the silicon melt, thereby reducing the carbon content of the crystal.

[0012] Optionally, the heat-insulating device comprises a heat-insulating felt board, and at least a portion of the heat-insulating felt board is disposed in the second heat-insulating cylinder;

[0013] The thermal insulation felt plate is provided with a step-shaped through hole to form a second channel, and the second channel is connected to the first channel.

[0014] In this embodiment, the step-shaped through hole constitutes the second channel, so that the second channel can be step-shaped, which can avoid direct discharge of gas and reduce heat loss.

[0015] Optionally, the stepped through hole comprises a first sub-through hole and a second sub-through hole arranged along the axial direction of the first heat-insulating cylinder, and the first sub-through hole is communicated with the first channel and the second sub-through hole respectively;

[0016] Along the axial direction of the first heat-insulating tube, the orthographic projection of the second sub-through hole coincides with a partial orthographic projection of the first sub-through hole, and the second sub-through hole and the first channel are staggered along a first direction, and the first direction is perpendicular to the axial direction of the first heat-insulating tube.

[0017] In this embodiment, the gas can be prevented from being directly discharged from the second channel, thereby reducing heat loss and lowering energy consumption.

[0018] Optionally, a height of the first sub-through hole in the axial direction of the first heat-insulating cylinder is greater than or equal to 20 mm.

[0019] In this embodiment, it is convenient to ensure that the airflow passes through the second channel smoothly.

[0020] Optionally, the heat-insulating device comprises a protective shell, wherein the protective shell is disposed in the stepped through hole, the protective shell encloses and forms the second channel, and the protective shell is used to protect the heat-insulating felt.

[0021] In this embodiment, the thermal insulation felt can be protected and the service life of the thermal insulation felt can be increased.

[0022] Optionally, the thermal insulation felt plate comprises a first thermal insulation portion and a second thermal insulation portion which are sequentially connected along the axial direction of the first thermal insulation cylinder;

[0023] The first heat-insulating portion is embedded in the second heat-insulating tube, and the outer wall of the first heat-insulating portion abuts against the inner wall of the second heat-insulating tube;

[0024] The second heat-insulating portion is located below the first heat-insulating portion and is connected to the first heat-insulating tube and the second heat-insulating tube respectively. The second heat-insulating portion is provided with the step-shaped through hole.

[0025] In this embodiment, the bottom of the second heat preservation tube can be sealed to prevent heat from escaping from the bottom of the second heat preservation tube.

[0026] Partial loss, reduce energy consumption.

[0027] Optionally, in the axial direction of the first heat-insulating cylinder, the top of the second heat-insulating cylinder is lower than the top of the first heat-insulating cylinder, so that the gas inlet is formed at the top of the second heat-insulating cylinder.

[0028] In this embodiment, it is convenient to form a gas inlet at the top of the second heat-insulating cylinder to reduce heat loss.

[0029] Optionally, the heat preservation device further comprises a first annular heat preservation plate and a second annular heat preservation plate disposed in the second heat preservation cylinder;

[0030] The second annular heat-insulating plate and the first annular heat-insulating plate are spaced apart from each other along the axial direction of the first heat-insulating cylinder.

[0031] In this embodiment, the first annular heat-insulating plate and the second annular heat-insulating plate can both reflect heat radiation, thereby effectively ensuring the temperature of the thermal field environment.

[0032] Optionally, the second annular heat-insulating plate is connected to the first annular heat-insulating plate via a connecting piece, and the first annular heat-insulating plate is placed on a side of the first heat-insulating portion away from the second heat-insulating portion; or,

[0033] The second annular insulation plate is connected to the first annular insulation plate through a connecting piece, and the second annular insulation plate or the first annular insulation plate is connected to the inner wall of the second insulation tube; in the axial direction of the first insulation tube, the second annular insulation plate and the first annular insulation plate are located in the first insulation part, in the second insulation part, or between the first insulation part and the second insulation part.

[0034] In this embodiment, the diversity of arrangements of the first annular heat-insulating plate and the second annular heat-insulating plate can be improved.

[0035] Optionally, a spacing between the first annular heat-insulating plate and the second annular heat-insulating plate in the axial direction of the first heat-insulating cylinder is greater than or equal to 5 mm.

[0036] In this embodiment, the reflection effect of the first annular thermal insulation plate and the second annular thermal insulation plate on thermal radiation can be improved.

[0037] Optionally, the insulation felt plate is provided with an avoidance hole penetrating the first insulation part and the second insulation part, and the inner diameter of the avoidance hole, the inner diameter of the first annular insulation plate, and the inner diameter of the second annular insulation plate are the same.

[0038] In this embodiment, it is possible to ensure that the tow bar passes through and to reduce heat loss as much as possible.

[0039] Optionally, the first heat-insulating cylinder comprises a first cylinder body and a second cylinder body arranged along its axial direction;

[0040] The inner diameter of the first cylinder is equal to the inner diameter of the second cylinder, and the first cylinder and the second cylinder are connected in sequence along the axial direction of the first insulation cylinder, or the inner diameter of the first cylinder is smaller than the inner diameter of the second cylinder, and the first cylinder and the second cylinder are connected by a first transition plate.

[0041] In this embodiment, the structural diversity of the first heat-insulating cylinder can be improved.

[0042] Optionally, the second heat-insulating cylinder comprises a third cylinder body and a fourth cylinder body arranged along the axial direction of the first heat-insulating cylinder;

[0043] The inner diameter of the third cylinder is equal to the inner diameter of the fourth cylinder, and the third cylinder and the fourth cylinder are connected in sequence along the axial direction of the first insulation cylinder, or the inner diameter of the third cylinder is smaller than the inner diameter of the fourth cylinder, and the third cylinder and the fourth cylinder are connected via a second transition plate.

[0044] In this embodiment, the structural diversity of the second heat-insulating cylinder can be improved.

[0045] Optionally, the difference between the inner diameter of the first heat-insulating cylinder and the outer diameter of the second heat-insulating cylinder is greater than or equal to 20 mm.

[0046] In this embodiment, it is convenient to ensure that the airflow passes through the first channel smoothly.

[0047] In a second aspect, the embodiment of the utility model further provides a crystal pulling system, comprising: a single crystal furnace and a crucible, a heater and the above-mentioned heat preservation device arranged in the single crystal furnace;

[0048] The heater is arranged around the crucible and is used to heat the silicon material in the crucible;

[0049] The heater is arranged in the second heat preservation cylinder of the heat preservation device.

[0050] The utility model embodiment includes the following advantages:

[0051] In an embodiment of the utility model, the first insulation tube is sleeved outside the second insulation tube, so that the insulation device can form a double-layer insulation structure, which can improve the effect of reflecting the heat of the heater. Under the joint action of the first insulation tube and the second insulation tube, the heat loss in the thermal field environment can be reduced, and the energy consumption can be reduced. Moreover, the first insulation tube and the second insulation tube can be disassembled and assembled separately, which can improve the convenience of disassembly and assembly of the insulation device. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 It is a structural schematic diagram of a crystal pulling system of the utility model;

[0053] Figure 2 It is a structural schematic diagram of another crystal pulling system of the utility model;

[0054] Figure 3 It is a partially enlarged schematic diagram of a heat preservation device of the utility model;

[0055] Figure 4 It is a top view of a second heat-insulating portion of the utility model;

[0056] Figure 5 This is a structural schematic diagram of a second heat preservation part of the utility model;

[0057] Figure 6 It is a cross-sectional view of a second heat-insulating portion of the utility model;

[0058] Figure 7 This is a structural schematic diagram of a second channel of the utility model;

[0059] Figure 8 It is a cross-sectional view of a second channel of the utility model.

[0060] Description of reference numerals:

[0061] 1-first insulation cylinder, 11-first cylinder, 12-second cylinder, 13-first transition plate, 2-second insulation cylinder, 21-third cylinder, 22-fourth cylinder, 23-second transition plate, 3-insulation felt plate, 31-first insulation part, 32-second insulation part, 33-avoidance hole, 34-protective shell, 35-step-type through hole, 351-first sub-through hole, 352-second sub-through hole, 4-first channel, 51-first annular insulation plate, 52-second annular insulation plate, 53-connecting piece, 531-first sub-connecting piece, 532-second sub-connecting piece, 6-insulation felt, 71-crucible, 72-drag rod, 73-heater, 74-insulation cover, 75-heat shield. DETAILED DESCRIPTION

[0062] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0063] The term "first" or "second" in the specification and claims of this application may include one or more of the features explicitly or implicitly. In the description of this utility model, unless otherwise specified, "multiple" means two or more. In addition, "and / or" in the specification and claims means at least one of the connected objects, and the character " / " generally means that the objects connected before and after are in an "or" relationship.

[0064] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0065] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0066] One of the core concepts of the embodiments of the present utility model is to disclose a heat preservation device, such as Figure 1-8 As shown, the heat-insulating device may specifically include: a first heat-insulating tube 1 and a second heat-insulating tube 2; wherein the first heat-insulating tube 1 may be sleeved outside the second heat-insulating tube 2, and there is a gap between the first heat-insulating tube 1 and the second heat-insulating tube 2, and the gap may constitute a first channel; or a part of the gap constitutes the first channel.

[0067] In the embodiment of the utility model, the first heat-insulating tube 1 is sleeved outside the second heat-insulating tube 2, so that the heat-insulating device can form a double-layer heat-insulating structure, which can improve the effect of reflecting the heat of the heater 73, thereby reducing the heat loss in the thermal field environment and reducing energy consumption. In addition, the first heat-insulating tube 1 and the second heat-insulating tube 2 can be disassembled and assembled separately, which improves the convenience of disassembly and assembly of the heat-insulating device.

[0068] In some optional embodiments of the present invention, the inner wall of the first insulation tube 1 and the outer wall of the second insulation tube 2 can be enclosed to form a first channel 4; a gas inlet is provided on the second insulation tube 2, or a gas inlet is formed between the first insulation tube 1 and the second insulation tube 2; the gas inlet is connected to the first channel 4 to facilitate the discharge of the gas in the second insulation tube 2.

[0069] In some optional embodiments of the present invention, a barrier or support member is arranged between the inner wall of the first heat-insulating tube 1 and the outer wall of the second heat-insulating tube 2 , and the barrier or support member and the first heat-insulating tube 1 and the second heat-insulating tube 2 form a first channel.

[0070] Specifically, as one of the implementation methods of this embodiment, a layer of insulation felt 6 is wrapped on the side of the first insulation tube 1 away from the second insulation tube 2. The insulation felt 6 can play a role in heat insulation. Under the joint action of the first insulation tube 1, the second insulation tube 2 and the insulation felt 6, the heat loss in the thermal field environment can be reduced and the energy consumption can be reduced. In this embodiment, the insulation felt 6 can be soft felt or solid felt. In addition, the insulation

[0071] The felt 6 may also be formed integrally with the first heat-insulating cylinder 1 .

[0072] The heat preservation device described in the embodiment of the utility model is used to protect the thermal field environment during the crystal pulling process, thereby ensuring the crystal pulling speed and crystal pulling quality of the single crystal silicon rod.

[0073] In the embodiment of the utility model, the first heat preservation cylinder 1 can support the heat preservation felt 6, and the heat preservation felt 6 can play a role of heat preservation and heat insulation. Figure 1 and Figure 2 As shown, the second insulation tube 2 can be installed outside the heater 73 and the crucible 71, wherein the first insulation tube 1 and the second insulation tube 2 can both reflect thermal radiation, reduce heat radiation and heat transfer to the outside, reduce heat loss, effectively ensure the thermal field environment in the second insulation tube 2, and reduce energy consumption.

[0074] Specifically, the material of the first insulation tube 1 can be graphite material, carbon-carbon composite material, etc., the material of the second insulation tube 2 can be graphite material, carbon-carbon composite material, insulation ceramics, etc., and the material of the insulation felt 6 can be solid felt or soft felt, etc.

[0075] Furthermore, in the axial direction of the first insulation tube 1, the top of the second insulation tube 2 is lower than the top of the first insulation tube 1, so that there is a height difference between the top of the second insulation tube 2 and the top of the first insulation tube 1, so that a gas inlet can be formed between the top of the second insulation tube 2 and the top of the first insulation tube 1.

[0076] Preferably, the height of the first insulation tube 1 is greater than the height of the second insulation tube 2, and the bottom of the first insulation tube 1 is arranged flush with the bottom of the second insulation tube 2, so as to form a gas inlet between the top of the second insulation tube 2 and the top of the first insulation tube 1.

[0077] Furthermore, the inner diameter of the first insulation tube 1 is larger than the outer diameter of the second insulation tube 2, the first insulation tube 1 and the second insulation tube 2 are arranged at intervals, and the inner wall of the first insulation tube 1 and the outer wall of the second insulation tube 2 enclose a first channel 4, so that the airflow in the second insulation tube 2 can enter the first channel 4 from the top of the second insulation tube 2, and the first channel 4 can guide the air path to discharge the airflow in the second insulation tube 2, and can replace the airflow to be discharged from the bottom of the second insulation tube 2, and eliminate the bottom exhaust hole. In this way, the bottom of the second insulation tube 2 can be sealed, reducing heat loss from the bottom of the second insulation tube 2, further reducing energy consumption, and can also reduce the carbon in the gas from entering the silicon melt, thereby reducing the crystalline carbon content.

[0078] Furthermore, the heat preservation device may include a heat preservation felt board 3, at least part of which is disposed in the second heat preservation cylinder 2. The heat preservation felt board 3 is provided with a step-shaped through hole 35 to form a second channel, which is connected to the first channel 4.

[0079] In the embodiment of the utility model, the second channel can play a role in guiding the gas in the first channel 4. Since the second channel is composed of the step-shaped through holes 35 on the insulation felt board 3, the direct discharge of the gas in the second channel can be avoided, which can further reduce the heat loss from the second channel and reduce energy consumption.

[0080] Specifically, the inner wall of the step-type through hole 35 may enclose and form a second channel.

[0081] Optionally, the stepped through hole 35 includes a first sub-through hole 351 and a second sub-through hole 352 arranged along the axial direction of the first heat-insulating cylinder 1, and the first sub-through hole 351 is connected to the first channel 4 and the second sub-through hole 352 respectively;

[0082] Along the axial direction of the first insulation tube 1, the orthographic projection of the second sub-through hole 352 coincides with the partial orthographic projection of the first sub-through hole 351, and the second sub-through hole 352 and the first channel 4 are staggered along the first direction, and the first direction is perpendicular to the axial direction of the first insulation tube 1, which can prevent the gas from being directly discharged from the second channel, reduce heat loss, and reduce energy consumption.

[0083] Specifically, Figure 2 As shown, the first sub-through hole 351 is connected to the second sub-through hole 352, and the first channel, the first sub-through hole 351 and the second sub-through hole 352 can be surrounded to form an inverted Z-shaped channel. Figure 4 , only illustrates a situation where the first direction is the radial direction of the first heat-insulating cylinder 1 , and other situations may refer to the settings, and the embodiments of the present utility model do not make specific limitations on this.

[0084] Furthermore, the height of the first sub-through hole 351 in the axial direction of the first heat-insulating cylinder 1 is greater than or equal to 20 mm, so as to ensure smooth airflow through the second channel. During the crystal pulling process, the gas contains impurities, which may accumulate in the through hole or channel. Therefore, a reasonable setting of the height or diameter of the through hole helps to avoid blockage of the through hole or channel.

[0085] Specifically, Figure 3 As shown, the height of the first sub-through hole 351 in the axial direction of the first heat-insulating cylinder 1 is H, and H≥20 mm.

[0086] Optionally, the insulation device includes a protective shell 34, which is arranged in the step-type through hole 35. The protective shell 34 encloses a second channel. The protective shell 34 is used to protect the insulation felt board 3, so that the air flow can flow from the protective shell 34 to avoid corrosion of the insulation felt board 3 and improve the service life of the insulation felt board 3.

[0087] Specifically, the material of the protective shell 34 may be graphite material, carbon-carbon composite material, etc.

[0088] Optionally, the insulation felt board 3 includes a first insulation part 31 and a second insulation part 32 which are connected in sequence along the axial direction of the first insulation tube 1; the first insulation part 31 is embedded in the second insulation tube 2, and the outer wall of the first insulation part 31 abuts against the inner wall of the second insulation tube 2; the second insulation part 32 is located below the first insulation part 31, and is respectively connected to the first insulation tube 1 and the second insulation tube 2, and a step-type through hole 35 is provided on the second insulation part 32.

[0089] In the embodiment of the utility model, the first heat-insulating portion 31 is embedded in the second heat-insulating tube 2, which can seal the bottom of the second heat-insulating tube 2, prevent heat from being lost from the bottom of the second heat-insulating tube 2, and reduce energy consumption.

[0090] Specifically, the number of the second channels may include one, two, or more, such as Figure 1 and Figure 2 , only a case where the number of the second channels is two is illustrated. Among them, at least two second channels can be arranged at intervals along the circumference of the first heat-insulating cylinder 1.

[0091] Specifically, the stepped through hole 35 is one way to constitute the second channel, and the protective shell 34 encloses the second channel, which is another way to constitute the second channel. The specific configuration can be based on actual needs, and the embodiment of the utility model does not make specific limitations on this.

[0092] Specifically, the insulation felt board 3 can play a role in heat insulation, and the material of the insulation felt board 3 can be solid felt or soft felt, etc. The insulation felt board 3 includes a first insulation part 31 and a second insulation part 32, and the first insulation part 31 and the second insulation part 32 can be integrally formed or spliced, and can be specifically set according to actual needs.

[0093] Specifically, the bottom of the thermal insulation felt plate 3 can be installed on the furnace bottom plate in the single crystal furnace.

[0094] Specifically, the insulation felt plate 3 may be provided with an avoidance hole 33 penetrating the first insulation part 31 and the second insulation part 32 . The avoidance hole 33 may be used to avoid the drag rod 72 . The drag rod 72 may abut against the bottom of the crucible 71 to support the crucible 71 .

[0095] Optionally, the insulation felt board 3 is provided with an avoidance hole 33 which passes through the first insulation part 31 and the second insulation part 32. The inner diameter of the avoidance hole 33, the inner diameter of the first annular insulation board 51, and the inner diameter of the second annular insulation board 52 can be the same. In this way, it can ensure that the drag rod 72 passes through and reduce heat loss as much as possible.

[0096] Optionally, the insulation device may also include a first annular insulation plate 51 and a second annular insulation plate 52; the second annular insulation plate 52 and the first annular insulation plate 51 are arranged at intervals along the axial direction of the first insulation tube 1, so that the first annular insulation plate 51 and the second annular insulation plate 52 can both reflect heat radiation to effectively ensure the temperature of the thermal field environment.

[0097] Optionally, the second annular insulation plate 52 is connected to the first annular insulation plate 51 through a connecting piece 53, and the first annular insulation plate 51 is placed on the side of the first insulation part 31 away from the second insulation part 32, so that the first annular insulation plate 51 can reflect heat radiation and protect the insulation felt board 3.

[0098] Optionally, the second annular insulation plate 52 is connected to the first annular insulation plate 51 through a connecting piece 53, and the second annular insulation plate 52 or the first annular insulation plate 51 is connected to the inner wall of the second insulation tube 2, so as to fix the first annular insulation plate 51 and the second annular insulation plate 52.

[0099] Specifically, in the axial direction of the first insulation tube 1, the second annular insulation plate 52 and the first annular insulation plate 51 are located in the first insulation part 31, the second insulation part 32, or between the first insulation part 31 and the second insulation part 32, which can improve the diversity of the arrangement of the first annular insulation plate 51 and the second annular insulation plate 52.

[0100] Specifically, in the axial direction of the first heat-insulating barrel 1, the first heat-insulating portion 31 may include two heat-insulating layers spaced apart, and the first annular heat-insulating plate 51 and the second annular heat-insulating plate 52 are both disposed between the two heat-insulating layers, so that the first annular heat-insulating plate 51 and the second annular heat-insulating plate 52 may both be located in the first heat-insulating portion 31; or, in the axial direction of the first heat-insulating barrel 1, the second heat-insulating portion 32 may include two heat-insulating layers spaced apart, and the first annular heat-insulating plate 51 and the second annular heat-insulating plate 52 are both disposed between the two heat-insulating layers, so that the first annular heat-insulating plate 51 and the second annular heat-insulating plate 52 may both be located in the second heat-insulating portion 32; or, the first annular heat-insulating plate 51 and the second annular heat-insulating plate 52 may both be located between the first heat-insulating portion 31 and the second heat-insulating portion 32. In the embodiment of the utility model, the first annular heat-insulating plate 51 and the second annular heat-insulating plate 52 may be disposed at any position of the second heat-insulating barrel 2 along its axial direction, wherein the axial direction of the second heat-insulating barrel 2 is consistent with the axial direction of the first heat-insulating barrel 1.

[0101] Optionally, the first annular insulation plate 51 and the second annular insulation plate 52 are located between the first insulation portion 31 and the second insulation portion 32 , and the first annular insulation plate 51 can cover the first insulation portion 31 to improve the protection of the insulation felt plate 3 .

[0102] Specifically, Figure 1 and Figure 2 As shown, the first annular insulation plate 51 and the second annular insulation plate 52 are both arranged at the bottom of the heater 73. The first annular insulation plate 51 and the second annular insulation plate 52 can reflect heat radiation from the bottom so that the heat radiation concentrates on heating the crucible 71, which can reduce energy consumption.

[0103] Specifically, the first annular thermal insulation plate 51 and the second annular thermal insulation plate 52 can both be used to reflect heat radiation. The material of the first annular thermal insulation plate 51 can be selected from graphite material, carbon-carbon composite material, or a mixture of upper and lower layers of graphite material and carbon-carbon composite material, etc. The material of the second annular thermal insulation plate 52 can be selected from graphite material, carbon-carbon composite material, or a mixture of upper and lower layers of graphite material and carbon-carbon composite material, etc.

[0104] Specifically, the first annular insulation plate 51 and the second annular insulation plate 52 are both annular structures, and the axes of the first annular insulation plate 51 and the second annular insulation plate 52 coincide with the axis of the first insulation cylinder 1. The second annular insulation plate 52 is connected to the first annular insulation plate 51 through a connector 53 near the inner circumference, so as to facilitate fixing the second annular insulation plate 52.

[0105] Specifically, the first annular heat-insulating plate 51, the connecting piece 53 and the second annular heat-insulating plate 52 can be integrally formed or spliced.

[0106] Furthermore, the connecting member 53 may include a first sub-connecting member 531 and a second sub-connecting member 532. The first sub-connecting member 531 and the second sub-connecting member 532 may be snap-fitted and connected. The first sub-connecting member 531 may be disposed on the side of the first annular insulation plate 51 facing the second annular insulation plate 52, and the second sub-connecting member 532 may be disposed on the side of the second annular insulation plate 52 facing the first annular insulation plate 51.

[0107] Optionally, the axial distance between the first annular insulation plate 51 and the second annular insulation plate 52 in the first insulation tube 1 may be greater than or equal to 5 mm, which may improve the reflection effect of the first annular insulation plate 51 and the second annular insulation plate 52 on heat radiation.

[0108] Specifically, Figure 3 As shown, the distance between the first annular heat-insulating plate 51 and the second annular heat-insulating plate 52 in the axial direction of the first heat-insulating cylinder 1 is h, and h≥5 mm.

[0109] Optionally, the first thermal insulation cylinder 1 includes a first cylinder 11 and a second cylinder 12 arranged along its axial direction; the inner diameter of the first cylinder 11 is equal to the inner diameter of the second cylinder 12, and the first cylinder 11 and the second cylinder 12 are connected in sequence along the axial direction of the first thermal insulation cylinder 1, or the inner diameter of the first cylinder 11 is smaller than the inner diameter of the second cylinder 12, and the first cylinder 11 and the second cylinder 12 are connected by a first transition plate 13.

[0110] In the embodiment of the utility model, the inner diameter of the first cylinder 11 is equal to the inner diameter of the second cylinder 12, so that the first insulation cylinder 1 can be an equal-diameter cylinder; the inner diameter of the first cylinder 11 is smaller than the inner diameter of the second cylinder 12, and the first cylinder 11 and the second cylinder 12 are connected by a first transition plate 13, so that the first insulation cylinder 1 can be a non-equal-diameter cylinder, which can improve the structural diversity of the first insulation cylinder 1.

[0111] Specifically, the first barrel 11 may be an upper insulation barrel of the first insulation barrel 1, and the second barrel 12 may be a middle insulation barrel of the first insulation barrel 1, or the second barrel 12 may be a lower insulation barrel of the first insulation barrel 1.

[0112] A combination of a middle insulation tube and a lower insulation tube.

[0113] Specifically, the inner circumference of the first transition plate 13 may be connected to the first cylinder 11 , and the outer circumference of the first transition plate 13 may be connected to the second cylinder 12 .

[0114] Optionally, the second heat-insulating barrel 2 may include a third barrel 21 and a fourth barrel 22 arranged along the axial direction of the first heat-insulating barrel 1; the inner diameter of the third barrel 21 is equal to the inner diameter of the fourth barrel 22, and the third barrel 21 and the fourth barrel 22 are sequentially connected along the axial direction of the first heat-insulating barrel 1. Alternatively, the inner diameter of the third barrel 21 is smaller than the inner diameter of the fourth barrel 22, and the third barrel 21 and the fourth barrel 22 may be connected via a second transition plate 23.

[0115] In the embodiment of the utility model, the inner diameter of the third cylinder 21 is equal to the inner diameter of the fourth cylinder 22, so that the second insulation cylinder 2 can be an equal-diameter cylinder; the inner diameter of the third cylinder 21 is smaller than the inner diameter of the fourth cylinder 22, and the third cylinder 21 and the fourth cylinder 22 are connected by a second transition plate 23, so that the second insulation cylinder 2 can be a non-equal-diameter cylinder, which can improve the structural diversity of the second insulation cylinder 2.

[0116] Specifically, the third cylinder 21 can be the upper insulation cylinder of the second insulation cylinder 2, the fourth cylinder 22 can be the middle insulation cylinder of the second insulation cylinder 2, or the fourth cylinder 22 can be a combination of the middle insulation cylinder and the lower insulation cylinder of the second insulation cylinder 2.

[0117] Specifically, the inner circumference of the second transition plate 23 may be connected to the third cylinder 21 , and the outer circumference of the second transition plate 23 may be connected to the third cylinder 21 .

[0118] Specifically, in the embodiment of the utility model, the combination of the first heat-insulating cylinder 1 and the second heat-insulating cylinder 2 can be the following combinations. The inner diameter of the first cylinder 11 is equal to the inner diameter of the second cylinder 12, and the inner diameter of the corresponding third cylinder 21 is equal to the inner diameter of the fourth cylinder 22. Or, Figure 2 As shown, the inner diameter of the first cylinder 11 is equal to the inner diameter of the second cylinder 12, the corresponding inner diameter of the third cylinder 21 is smaller than the inner diameter of the fourth cylinder 22, and the third cylinder 21 and the fourth cylinder 22 are connected by the second transition plate 23. Alternatively, the inner diameter of the first cylinder 11 is smaller than the inner diameter of the second cylinder 12, the first cylinder 11 and the second cylinder 12 are connected by the first transition plate 13, and the corresponding inner diameter of the third cylinder 21 is equal to the inner diameter of the fourth cylinder 22. Alternatively, as Figure 1 As shown, the inner diameter of the first cylinder 11 is smaller than the inner diameter of the second cylinder 12, and the first cylinder 11 and the second cylinder 12 are connected by a first transition plate 13. The corresponding inner diameter of the third cylinder 21 is smaller than the inner diameter of the fourth cylinder 22, and the third cylinder 21 and the fourth cylinder 22 are connected by a second transition plate 23.

[0119] Optionally, the difference between the inner diameter of the first insulation tube 1 and the outer diameter of the second insulation tube 2 is greater than or equal to 20 mm, so that the interlayer spacing between the first insulation tube 1 and the second insulation tube 2, that is, the width of the first channel 4, can be greater than or equal to 10 mm, thereby ensuring smooth airflow through the first channel 4.

[0120] Specifically, Figure 3 As shown, the difference between the inner diameter of the first heat-insulating tube 1 and the outer diameter of the second heat-insulating tube 2 is 2r, where r≥10 mm.

[0121] The heat preservation device described in the embodiment of the utility model has at least the following advantages:

[0122] In an embodiment of the utility model, the first insulation tube is sleeved outside the second insulation tube, so that the insulation device can form a double-layer insulation structure, which can improve the effect of reflecting the heat of the heater. Under the joint action of the first insulation tube and the second insulation tube, the heat loss in the thermal field environment can be reduced, and the energy consumption can be reduced. Moreover, the first insulation tube and the second insulation tube can be disassembled and assembled separately, which can improve the convenience of disassembly and assembly of the insulation device.

[0123] In the second aspect, an embodiment of the utility model further discloses a crystal pulling system, comprising: a single crystal furnace and a crucible 71, a heater 73 and a heat preservation device arranged in the single crystal furnace; the heater 73 is arranged around the crucible 71 and is used to heat the silicon material in the crucible 71; the heater 73 is arranged in the second heat preservation tube 2 of the heat preservation device.

[0124] In the embodiment of the utility model, the heater 73 is arranged around the crucible 71, and can heat the silicon material in the crucible 71 to pull the single crystal silicon rod. The heater 73 is arranged in the second insulation tube 2 of the insulation device, so that the first insulation tube 1 and the second insulation tube 2 can form a double-layer insulation structure, and the first insulation tube 1 and the second insulation tube 2 can both reflect the heat radiation of the heater 73. Moreover, a layer of insulation felt 6 is wrapped on the side of the first insulation tube 1 away from the second insulation tube 2, so that the insulation felt 6 can also play a role of heat insulation, so that the heat radiation loss of the heater 73 can be reduced, and the energy consumption of the single crystal silicon rod during the crystal pulling process can be reduced.

[0125] Optionally, the crystal pulling system also includes an insulation cover 74; the outer periphery of the insulation cover 74 is connected to the top of the first insulation tube 1; a gas inlet is formed between the insulation cover 74 and the top of the second insulation tube 2, so that the airflow in the second insulation tube 2 can enter the first channel 4 through the gas inlet and then be discharged.

[0126] Optionally, the crystal pulling system also includes a heat shield 75, which is arranged above the crucible 71. The heat shield 75 can be used to exchange heat for the single crystal silicon rod to increase the longitudinal temperature gradient of the single crystal silicon rod and improve the crystal pulling speed of the single crystal silicon rod; the heat shield 75 is connected to the inner periphery of the insulation cover 74, and the insulation cover 74 can support and fix the heat shield 75.

[0127] The crystal pulling system described in the embodiment of the utility model has at least the following advantages:

[0128] In an embodiment of the utility model, the first insulation tube is sleeved outside the second insulation tube, so that the insulation device can form a double-layer insulation structure, which can improve the effect of reflecting the heat of the heater. Under the joint action of the first insulation tube and the second insulation tube, the heat loss in the thermal field environment can be reduced, and the energy consumption can be reduced. Moreover, the first insulation tube and the second insulation tube can be disassembled and assembled separately, which can improve the convenience of disassembly and assembly of the insulation device.

[0129] Although the preferred embodiments of the utility model embodiments have been described, those skilled in the art may make additional 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 that fall within the scope of the utility model embodiments.

[0130] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or terminal device including the elements.

[0131] The above is a detailed introduction to a heat preservation device and a crystal pulling system provided by the utility model. Specific examples are used in this article to illustrate the principle and implementation mode of the utility model. The description of the above embodiments is only used to help understand the method of the utility model and its core idea. At the same time, for general technical personnel in this field, according to the idea of ​​the utility model, there will be changes in the specific implementation mode and application scope. In summary, the content of this specification should not be understood as a limitation on the utility model.

Claims

1. A heat preservation device, used in a single crystal furnace, characterized in that: include: A first heat preservation tube and a second heat preservation tube; wherein, The first heat-insulating cylinder is sleeved outside the second heat-insulating cylinder, and a gap is provided between the first heat-insulating cylinder and the second heat-insulating cylinder, and at least a part of the gap constitutes a first channel; A gas inlet is provided on the second heat-insulating cylinder, or the gas inlet is formed between the first heat-insulating cylinder and the second heat-insulating cylinder; The gas inlet is in communication with the first channel.

2. The heat preservation device according to claim 1, characterized in that: The heat preservation device comprises a heat preservation felt plate, at least part of which is arranged in the second heat preservation cylinder; The thermal insulation felt plate is provided with a step-shaped through hole to form a second channel; the second channel is connected to the first channel.

3. The heat preservation device according to claim 2, characterized in that: The stepped through hole comprises a first sub-through hole and a second sub-through hole arranged along the axial direction of the first heat-insulating cylinder, and the first sub-through hole is communicated with the first channel and the second sub-through hole respectively; Along the axial direction of the first heat-insulating tube, the orthographic projection of the second sub-through hole coincides with a partial orthographic projection of the first sub-through hole; the second sub-through hole and the first channel are staggered along a first direction, and the first direction is perpendicular to the axial direction of the first heat-insulating tube.

4. The heat preservation device according to claim 3, characterized in that: A height of the first sub-through hole in the axial direction of the first heat-insulating cylinder is greater than or equal to 20 mm.

5. The heat preservation device according to claim 2, characterized in that: The heat-insulating device comprises a protective shell, which is arranged in the step-shaped through hole and encloses the second channel. The protective shell is used to protect the heat-insulating felt board.

6. The heat preservation device according to claim 2, characterized in that: The thermal insulation felt plate comprises a first thermal insulation portion and a second thermal insulation portion which are sequentially connected along the axial direction of the first thermal insulation cylinder; The first heat-insulating portion is embedded in the second heat-insulating tube, and the outer wall of the first heat-insulating portion abuts against the inner wall of the second heat-insulating tube; The second heat-insulating portion is located below the first heat-insulating portion and is connected to the first heat-insulating tube and the second heat-insulating tube respectively. The second heat-insulating portion is provided with the step-shaped through hole.

7. The heat preservation device according to claim 1, characterized in that: In the axial direction of the first heat-insulating tube, the top of the second heat-insulating tube is lower than the top of the first heat-insulating tube, so that the gas inlet is formed at the top of the second heat-insulating tube.

8. The heat preservation device according to claim 6, characterized in that: The heat preservation device further comprises a first annular heat preservation plate and a second annular heat preservation plate arranged in the second heat preservation cylinder; The second annular heat-insulating plate and the first annular heat-insulating plate are spaced apart from each other along the axial direction of the first heat-insulating cylinder.

9. The heat preservation device according to claim 8, characterized in that: The second annular heat-insulating plate is connected to the first annular heat-insulating plate through a connecting piece, and the first annular heat-insulating plate is placed on a side of the first heat-insulating portion away from the second heat-insulating portion; or, The second annular insulation plate is connected to the first annular insulation plate through a connecting piece, and the second annular insulation plate or the first annular insulation plate is connected to the inner wall of the second insulation tube; in the axial direction of the first insulation tube, the second annular insulation plate and the first annular insulation plate are located in the first insulation part, in the second insulation part, or between the first insulation part and the second insulation part.

10. The heat preservation device according to claim 8, characterized in that: The distance between the first annular heat-insulating plate and the second annular heat-insulating plate in the axial direction of the first heat-insulating cylinder is greater than or equal to 5 mm.

11. The heat preservation device according to claim 1, characterized in that: The first heat-insulating cylinder comprises a first cylinder body and a second cylinder body arranged along its axial direction; The inner diameter of the first cylinder is equal to the inner diameter of the second cylinder, and the first cylinder and the second cylinder are sequentially connected along the axial direction of the first heat-insulating cylinder; Alternatively, the inner diameter of the first cylinder is smaller than the inner diameter of the second cylinder, and the first cylinder and the second cylinder are connected via a first transition plate.

12. The heat preservation device according to claim 1, characterized in that: The second heat-insulating cylinder comprises a third cylinder body and a fourth cylinder body which are arranged along the axial direction of the first heat-insulating cylinder; The inner diameter of the third cylinder is equal to the inner diameter of the fourth cylinder, and the third cylinder and the fourth cylinder are sequentially connected along the axial direction of the first heat-insulating cylinder; Alternatively, the inner diameter of the third cylinder is smaller than the inner diameter of the fourth cylinder, and the third cylinder and the fourth cylinder are connected via a second transition plate.

13. The heat preservation device according to claim 1, characterized in that: The difference between the inner diameter of the first heat-insulating cylinder and the outer diameter of the second heat-insulating cylinder is greater than or equal to 20 mm.

14. A crystal pulling system, characterized in that: include: A single crystal furnace, a crucible and a heater arranged in the single crystal furnace, and a heat preservation device according to any one of claims 1 to 13; The heater is arranged around the crucible and is used to heat the silicon material in the crucible; The heater is arranged in the second heat preservation cylinder of the heat preservation device.

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