Heating furnace for zone-melting purification

Abstract

The utility model relates to the technical field of zone-melting purification, and discloses a heating furnace for zone-melting purification, which comprises a shell, a heat preservation layer, a heat preservation furnace body and a temperature sensor, a cavity is formed in the heat preservation furnace body, electric heating alloy furnace wires are embedded in the inner wall of the cavity, the electric heating alloy furnace wires are annularly and evenly distributed around the axis of the cavity and used for generating a temperature field in the cavity, and mounting holes used for being communicated with the cavity are coaxially formed in the two ends of the heat preservation furnace body. And the temperature sensor is vertically arranged at the top of the shell, the temperature sensor is provided with an external thread used for being in threaded connection with the shell, scales are arranged in the extending direction of the external thread, and the lower end of the temperature sensor penetrates through the heat preservation furnace body to extend to the cavity and is used for measuring the heating temperature in the temperature field. The utility model has the beneficial effects that the installation precision of the temperature sensor in a temperature field is improved, the stability of the temperature field is improved, and the purification effect is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of zone melting purification, in particular to a heating furnace used for zone melting purification. Background Art

[0002] Zone melting purification is mainly used for the purification of metals and semiconductor materials. By locally heating the material in a heating furnace, a small section of the solid material is melted into liquid. As the heating furnace moves, the melting zone slowly moves from one end of the material to the other. At the end of the melting zone, the melt solidifies, and the impurity elements are enriched at the head and tail of the material due to the different solubility in the solid phase and the liquid phase, thereby achieving purification.

[0003] The existing heating furnace will generate a stable temperature field through the electric heating element. The farther away from the temperature field, the lower the temperature, and the closer to the temperature field, the higher the temperature. In order to facilitate the monitoring of the heating temperature of the material, a temperature sensor is generally inserted into the temperature field. However, the installation depth of the existing temperature sensor in the temperature field is difficult to determine each time, and the installation accuracy is low. It is difficult to measure the actual heating temperature of the material, which affects the purification effect.

[0004] In addition, in the prior art, the thermal insulation effect in the furnace is poor, which causes the heat in the temperature field to easily exchange heat with the external environment, resulting in heat dissipation. The stability of the temperature field is poor, affecting the purification effect. Utility Model Content

[0005] The purpose of the utility model is to provide a heating furnace for zone melting purification, improve the installation accuracy of the temperature sensor in the temperature field, improve the stability of the temperature field, and enhance the purification effect.

[0006] In order to achieve the above-mentioned purpose, the utility model provides a heating furnace for zone melting purification, comprising: a shell, a heat-insulating layer, a heat-insulating furnace body, and a temperature sensor;

[0007] The heat-insulating furnace body is arranged in the shell, and an installation gap is arranged between the heat-insulating furnace body and the shell, and the heat-insulating layer is used to fill the installation gap;

[0008] A cavity is provided inside the heat preservation furnace body, and an electric heating alloy furnace wire is embedded in the inner wall of the cavity. The electric heating alloy furnace wire is evenly distributed in a ring around the axis of the cavity. The electric heating alloy furnace wire is used to generate a temperature field in the cavity. Mounting holes for communicating with the cavity are coaxially provided at both ends of the heat preservation furnace body. Materials are inserted in the mounting holes, and through holes corresponding to the mounting holes are opened on the outer shell;

[0009] The temperature sensor is vertically arranged on the top of the outer shell, and is provided with an external thread for threaded connection with the outer shell, and a scale is provided along the extension direction of the external thread. The lower end of the temperature sensor passes through the insulation furnace body and extends to the cavity, and is used to measure the heating temperature in the temperature field.

[0010] Furthermore, the temperature sensor includes a measuring rod, a measuring element, a protective cover and a wire crimping assembly, the outer wall of the measuring rod is provided with the external thread and the scale, the end face of the measuring rod is axially provided with a wire threading hole, one end of the measuring rod is fixedly provided with the measuring element, the protective cover is arranged outside the measuring element, the other end of the measuring rod is provided with the wire crimping assembly, and the wire of the measuring element passes through the wire threading hole and is fixed by the wire crimping assembly.

[0011] Furthermore, a limit bracket is detachably provided on the top of the shell, a threaded hole corresponding to the external thread is opened on the limit bracket, and a limit top screw is circumferentially provided on the limit bracket near the threaded hole. The limit top screw abuts against the temperature sensor and is used to limit the axial installation of the temperature sensor.

[0012] Furthermore, a fixing hole is formed on the side wall of the limiting bracket, the fixing hole extends to the threaded hole, and the axis of the fixing hole is perpendicular to the axis of the threaded hole.

[0013] Furthermore, the limiting bracket has a Z-shape in appearance.

[0014] Furthermore, the heat preservation furnace body is provided with a limiting hole corresponding to the lower end of the temperature sensor in the vertical direction, and a curing agent is filled between the inner wall of the limiting hole and the outer wall of the temperature sensor.

[0015] Furthermore, the heat-insulating furnace body is made of alumina polycrystalline fiber material.

[0016] Furthermore, the volume of the electrothermal alloy furnace wire embedded in the inner wall of the cavity accounts for 35%-50% of the total volume of the electrothermal alloy furnace wire.

[0017] Furthermore, a ceramic insulator is provided on the top of the shell, which is used to lead the two ends of the electric heating alloy furnace wire out of the heat-insulating furnace body and connect them to an external power source.

[0018] Furthermore, the outer shell includes a mounting base and an upper shell, the upper shell is hollow inside and open at the lower end, the heat preservation furnace body is located in the upper shell, the open lower end cover is provided with the mounting base, and the mounting hole is provided in the upper shell.

[0019] The utility model embodiment is a heating furnace for zone melting purification. Compared with the prior art, its beneficial effect is that: an insulation layer is filled between the insulation furnace body and the shell, reducing the heat exchange between the insulation furnace body and the external environment. At the same time, a cavity is provided inside the insulation furnace body, and an electric heating alloy furnace wire is embedded in the inner wall of the cavity to improve the stability of the installation of the electric heating alloy furnace wire. The insulation furnace body and the insulation layer are made of insulation materials to achieve double insulation, which can make the heat in the cavity difficult to dissipate, reduce energy consumption, and improve the stability of the temperature field. In addition, the temperature sensor is threadedly connected to the shell and is provided with a scale to control the installation depth of the temperature sensor in the temperature field, and the actual heating temperature of the material can be accurately measured to improve the purification effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic structural diagram of a heating furnace used for zone melting purification in an embodiment of the utility model;

[0021] Figure 2 It is a cross-sectional view of a heating furnace used for zone melting purification according to an embodiment of the utility model;

[0022] Figure 3 yes Figure 2 A partial enlarged view of the middle A;

[0023] Figure 4 It is a schematic diagram of the structure of a temperature sensor for a heating furnace used for zone melting purification according to an embodiment of the utility model;

[0024] Figure 5 This is a front view of a temperature sensor for a heating furnace used for zone melting purification according to an embodiment of the utility model;

[0025] Figure 6 It is a side view of a temperature sensor of a heating furnace used for zone melting purification according to an embodiment of the utility model;

[0026] Figure 7 It is a structural schematic diagram of a limiting bracket of a heating furnace for zone melting purification according to an embodiment of the utility model;

[0027] Figure 8 It is a schematic structural diagram of an electric heating alloy furnace wire of a heating furnace used for zone melting purification according to an embodiment of the utility model.

[0028] In the figure, 1, shell; 11, mounting base; 12, upper shell; 100, through hole; 2, insulation layer; 3, insulation furnace body; 31, cavity; 32, mounting hole; 4, temperature sensor; 41, measuring rod; 411, external thread; 412, scale; 413, threading hole; 414, mounting boss; 42, measuring element; 43, protective cover; 44, wire pressing assembly; 441, fixing plate; 4411, wire passing hole; 442, wire pressing screw; 443, metal connector; 45, thermal insulation sheet; 5, electric heating alloy furnace wire; 6, limit bracket; 61, threaded hole; 62, limit top screw; 63, fixing hole; 7, ceramic insulator. DETAILED DESCRIPTION

[0029] The following is a further detailed description of the specific implementation of the present invention in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0030] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "inside", "outside", etc. used in the present invention to indicate the orientation or positional relationship are based on the positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred devices and elements must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0031] like Figure 1 , Figure 2 , Figure 3 As shown, a heating furnace for zone melting purification according to a preferred embodiment of the utility model comprises: an outer shell 1, an insulation layer 2, an insulation furnace body 3, and a temperature sensor 4, wherein the insulation furnace body 3 is arranged in the outer shell 1, and an installation gap is arranged between the outer shell 1, the insulation layer 2 is used to fill the installation gap, the insulation furnace body 3 itself is made of insulation material, and the arrangement of the insulation layer 2 forms a double insulation structure, which improves the overall insulation performance of the furnace body. In order to facilitate the installation of the electric heating alloy furnace wire 5 and improve the stability of the installation of the electric heating alloy furnace wire 5, a cavity 31 is arranged inside the insulation furnace body 3, and the inner wall of the cavity 31 is embedded with the electric heating alloy furnace wire 5, and the electric heating alloy furnace wire 5 is evenly distributed in a ring around the axis of the cavity 31, and the electric heating alloy furnace wire 5 is used to generate a temperature field in the cavity 31. In order to facilitate the installation of materials, mounting holes 32 for communicating with the cavity 31 are coaxially provided at both ends of the insulation furnace body 3, and a through hole 100 corresponding to the mounting hole 32 is opened on the outer shell 1, wherein the mounting hole 32 is used to insert the material so that part of the material is heated in the temperature field. The size of the mounting hole 32 can be adjusted according to the size of the material to minimize the gap between the material and the mounting hole 32, reduce the air convection caused by the temperature difference, and make the heating process of the material more stable.

[0032] In addition, the temperature sensor 4 is used to measure the heating temperature of the temperature field. In order to facilitate the accurate adjustment of the installation depth of the temperature sensor 4, so as to measure the actual heating temperature of the material and ensure the installation accuracy of the temperature sensor 4, in the present utility model, refer to Figures 1 to 3 The temperature sensor 4 is vertically arranged on the top of the shell 1. The temperature sensor 4 is provided with an external thread 411 for threaded connection with the shell 1, and a scale 412 is provided along the extension direction of the external thread 411. The lower end of the outer wall temperature sensor 4 penetrates the insulation furnace body 3 and extends to the cavity 31, so as to realize the rapid installation of the temperature sensor 4, obtain the installation depth of the temperature sensor 4, and measure the heating temperature in the temperature field at the same time.

[0033] Further, in this embodiment, in order to facilitate the design of the temperature sensor 4, refer to Figure 3 , Figure 4 , Figure 5 The temperature sensor 4 includes a measuring rod 41, a measuring element 42, a protective cover 43 and a wire crimping assembly 44. Specifically, the outer wall of the measuring rod 41 is provided with an external thread 411 and a scale 412. The measuring element 42 is fixedly provided at one end of the measuring rod 41. The protective cover 43 is arranged outside the measuring element 42. The protective cover 43 is threadedly connected or adhesively fixed to the measuring rod 41. A wire crimping assembly 44 is provided at the other end of the measuring rod 41. In order to facilitate the wiring of the measuring element 42, a wire threading hole 413 is opened axially on the end face of the measuring rod 41. The wire of the measuring element 42 passes through the wire threading hole 413 and is fixed by the wire crimping assembly 44.

[0034] Specifically, in order to facilitate the installation between the measuring rod 41 and the wire pressing assembly 44, refer to Figure 4 , Figure 5 The end of the measuring rod near the wire pressing assembly 44 is provided with a mounting boss 414, and the wire threading hole 413 passes through the mounting boss 414. The wire pressing assembly 44 includes a fixing plate 441 and a wire pressing screw 442. The fixing plate 441 is provided with a wire hole 4411 corresponding to the wire threading hole 413. The fixing plate 441 and the mounting boss 414 are connected by the wire pressing screw 442. At the same time, the wire of the measuring element 42 passes through the wire threading hole 413 and is fixed by the wire pressing screw 442 through the wire hole 4411. In some embodiments, to facilitate wiring, refer to Figure 6 A metal connecting piece 443 is also provided on the end surface of the fixing plate 441. In this embodiment, the measuring rod 41 and the fixing plate 441 are both made of ceramic material. Furthermore, in order to avoid burns when connecting the wires of the measuring element 42 at the fixing plate 441 and reduce the influence of high temperature on external electrical components, a heat insulation sheet 45 is also provided between the mounting boss 414 and the fixing plate 441.

[0035] Furthermore, in this embodiment, in order to facilitate the installation of the temperature sensor 4, refer to Figure 3 , Figure 6 A limit bracket 6 is detachably provided on the top of the housing 1, wherein a threaded hole 61 corresponding to the external thread 411 is provided on the limit bracket 6. In order to limit the axial installation of the temperature sensor 4, a limit top screw 62 is circumferentially provided near the threaded hole 61 on the limit bracket 6. The limit top screw 62 abuts against the temperature sensor 4. Specifically, refer to Figure 3 The limiting top screw 62 abuts against the mounting boss 414 . The limiting top screw 62 is generally a screw and is threadedly connected to the limiting bracket 6 .

[0036] Furthermore, in order to prevent the temperature sensor 4 from shaking after installation, refer to Figure 7 , or when the temperature sensor 4 and the limit bracket 6 are threaded, they can still be firmly fixed to the limit bracket 6. In this embodiment, a fixing hole 63 is opened on the side wall of the limit bracket 6, and the fixing hole 63 extends to the threaded hole 61, and the axis of the fixing hole 63 is perpendicular to the axis of the threaded hole 61. A screw or an inner fastening nail can be set in the fixing hole 63 to fix the temperature sensor 4. Furthermore, in this embodiment, in order to facilitate the processing of the limit bracket 6, the shape of the limit bracket 6 is Z-shaped, and the shape can be adjusted accordingly according to actual needs.

[0037] Furthermore, in order to facilitate the insertion of the lower end of the temperature sensor 4 in the insulation furnace body 3, a limiting hole corresponding to the lower end of the temperature sensor 4 is opened in the insulation furnace body 3 along the vertical direction. In order to avoid the heat loss in the temperature field due to the installation gap between the limiting hole and the sensor, a curing agent is filled between the inner wall of the limiting hole and the outer wall of the temperature sensor 4. The curing agent can be made of insulation fiber that is resistant to high temperature and has good insulation effect.

[0038] Furthermore, in order to process and shape the heat preservation furnace body 3, in this embodiment, the heat preservation furnace body 3 is made of alumina polycrystalline fiber material, specifically, it is integrally formed through a vacuum forming process, wherein the heat preservation layer 2 is also made of alumina polycrystalline fiber. In order to improve the stability of the installation of the electric heating alloy furnace wire 5, the volume of the electric heating alloy furnace wire 5 embedded in the inner wall of the cavity 31 accounts for 35%-50% of the total volume of the electric heating alloy furnace wire 5. Further, in this embodiment, refer to Figure 8 , the diameter d of the electric heating alloy furnace wire 5 is set to 1, it is a spiral arrangement, the spiral pitch h is 2.2 times the diameter, and the spiral diameter D of the electric heating alloy furnace wire 5 is 8.8 times the diameter d of the electric heating alloy furnace wire 5, for example: d = 1mm, h = 2.2mm, D = 8.8mm. In this embodiment, the electric heating alloy furnace wire 5 is made of FeCrAl alloy.

[0039] Furthermore, in this embodiment, refer to Figure 1In order to facilitate the two ends of the electric heating alloy furnace wire 5 to be led out from the insulation furnace body 3 and connected to the external power supply, and to prevent the staff from contacting the electric heating alloy furnace wire 5, a ceramic insulator 7 is provided on the top of the shell 1.

[0040] Furthermore, in order to facilitate the design of the housing 1 and the installation of the heat preservation furnace body 3, the housing 1 includes a mounting base 11 and an upper shell 12. The upper shell 12 is hollow inside and open at the lower end. The heat preservation furnace body 3 is located in the upper shell 12. The lower end cover of the opening is provided with a mounting base 11, and a mounting hole 32 is provided in the upper shell 12. In order to improve the structural strength of the housing 1, the mounting base 11 and the upper shell 12 are made of 304 or 316 stainless steel.

[0041] In summary, the embodiment of the utility model provides a heating furnace for zone melting purification, in which an insulation layer 2 is filled between the insulation furnace body 3 and the outer shell 1 to reduce the heat exchange between the insulation furnace body 3 and the external environment. At the same time, a cavity 31 is provided inside the insulation furnace body 3, and an electric heating alloy furnace wire 5 is embedded in the inner wall of the cavity 31 to improve the stability of the installation of the electric heating alloy furnace wire 5. The insulation furnace body 3 and the insulation layer 2 are made of insulation materials to achieve double insulation, which can make the heat in the cavity 31 not easy to dissipate, reduce energy consumption, and improve the stability of the temperature field. In addition, the temperature sensor 4 is threadedly connected to the outer shell 1 and is provided with a scale to control the installation depth of the temperature sensor 4 in the temperature field, and can accurately measure the actual heating temperature of the material to improve the purification effect.

[0042] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principle of the present invention. These improvements and substitutions should also be regarded as the protection scope of the present invention.

Claims

1. A heating furnace for zone melting purification, characterized in that: include: Shell, insulation layer, insulation furnace body, temperature sensor; The heat-insulating furnace body is arranged in the shell, and an installation gap is arranged between the heat-insulating furnace body and the shell, and the heat-insulating layer is used to fill the installation gap; A cavity is provided inside the heat preservation furnace body, and an electric heating alloy furnace wire is embedded in the inner wall of the cavity. The electric heating alloy furnace wire is evenly distributed in a ring around the axis of the cavity. The electric heating alloy furnace wire is used to generate a temperature field in the cavity. Mounting holes for communicating with the cavity are coaxially provided at both ends of the heat preservation furnace body. Materials are inserted in the mounting holes, and through holes corresponding to the mounting holes are opened on the outer shell; The temperature sensor is vertically arranged on the top of the outer shell, and is provided with an external thread for threaded connection with the outer shell, and a scale is provided along the extension direction of the external thread. The lower end of the temperature sensor passes through the insulation furnace body and extends to the cavity, and is used to measure the heating temperature in the temperature field.

2. The heating furnace for zone melting purification according to claim 1, characterized in that: The temperature sensor includes a measuring rod, a measuring element, a protective cover and a wire crimping assembly. The outer wall of the measuring rod is provided with the external thread and the scale. The end face of the measuring rod is provided with a threading hole along the axial direction. The measuring element is fixedly provided at one end of the measuring rod. The protective cover is arranged outside the measuring element. The wire crimping assembly is provided at the other end of the measuring rod. The wire of the measuring element passes through the threading hole and is fixed by the wire crimping assembly.

3. The heating furnace for zone melting purification according to claim 1, characterized in that: A detachable limit bracket is provided on the top of the shell, a threaded hole corresponding to the external thread is opened on the limit bracket, and a limit top screw is circumferentially provided on the limit bracket near the threaded hole. The limit top screw abuts against the temperature sensor to limit the axial installation of the temperature sensor.

4. The heating furnace for zone melting purification according to claim 3, characterized in that: A fixing hole is formed on the side wall of the limiting bracket. The fixing hole extends to the threaded hole, and the axis of the fixing hole is perpendicular to the axis of the threaded hole.

5. The heating furnace for zone melting purification according to claim 3, characterized in that: The limiting bracket has a Z-shape in appearance.

6. The heating furnace for zone melting purification according to claim 1, characterized in that: The heat preservation furnace body is provided with a limiting hole corresponding to the lower end of the temperature sensor in the vertical direction, and a curing agent is filled between the inner wall of the limiting hole and the outer wall of the temperature sensor.

7. The heating furnace for zone melting purification according to claim 1, characterized in that: The heat-insulating furnace body is made of alumina polycrystalline fiber material.

8. The heating furnace for zone melting purification according to claim 1, characterized in that: The volume of the electrothermal alloy furnace wire embedded in the inner wall of the cavity accounts for 35%-50% of the total volume of the electrothermal alloy furnace wire.

9. The heating furnace for zone melting purification according to claim 1, characterized in that: A ceramic insulator is arranged on the top of the shell, which is used to lead the two ends of the electric heating alloy furnace wire out of the heat-insulating furnace body and connect them to an external power source.

10. The heating furnace for zone melting purification according to claim 1, characterized in that: The shell includes a mounting base and an upper shell. The upper shell is hollow inside and open at the lower end. The heat-insulating furnace body is located in the upper shell. The open lower end cover is provided with the mounting base. The mounting hole is provided in the upper shell.

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