A double-row graphite heater with uniformly variable axial temperature gradient

Abstract

The utility model discloses a double-row graphite heater with uniformly variable axial temperature gradient, and relates to the technical field of graphite heaters. The graphite heater comprises 6 heating components connected end to end, and the heating components comprise an upper connecting plate, a lower connecting plate and 2 groups of heating rods; each lower connecting plate is connected to the lower ends of the 2 groups of heating rods, and the upper ends of the second group of heating rods of the previous lower connecting plate and the upper ends of the first group of heating rods of the next lower connecting plate are connected to the same upper connecting plate; electrodes are provided between the 2 groups of heating rods located on the upper connecting plate; the resistance of the heating rods increases stepwise from the upper end to the lower end along the axial direction. The graphite heater of the utility model presents an increase in resistance in the axial direction, so that the current change increases linearly from bottom to top, and the electric heat also increases linearly. In the flow of the atmosphere from bottom to top, the temperature increases gradually and orderly, causing the relevant atmosphere reaction to go from shallow to deep, thus ensuring the atmosphere reaction throughout the process.

Description

Technical Field

[0001] The utility model relates to the technical field of graphite heaters, in particular to a double-row graphite heater with uniformly variable axial temperature gradients. Background Art

[0002] At present, it is difficult for the chemical vapor deposition process to maintain a certain chemical reaction at the tail end in a long flow channel, and it is difficult to carry out effective and comprehensive deposition on a long workpiece. Therefore, the design of the reaction temperature in the flow channel is particularly important. The vertical furnace is a structure with bottom air intake and exhaust from bottom to top. It has a long flow field. How to optimize the thermal field structure and drive the chemical reaction process through the temperature gradient, so that the chemical reaction of the entire flow field cannot be fully reacted in advance, and the chemical reaction can be carried out effectively, so as to achieve the chemical vapor deposition effect of various parts of the product, is the current research hotspot. Utility Model Content

[0003] The technical problem to be solved by the utility model is to provide a double-row graphite heater with uniformly variable axial temperature gradient, so as to realize the gradient change of the internal thermal field of the heater.

[0004] In order to solve the above problems, the utility model proposes the following technical solutions:

[0005] A double-row graphite heater with uniformly variable axial temperature gradient comprises six heating components connected end to end, wherein the heating components comprise an upper connecting plate, a lower connecting plate and two groups of heating rods; each lower connecting plate is connected to the lower ends of the two groups of heating rods, the upper ends of the second group of heating rods of the preceding lower connecting plate and the upper ends of the first group of heating rods of the succeeding lower connecting plate are connected to the same upper connecting plate; an electrode is provided between the two groups of heating rods located on the upper connecting plate.

[0006] A further technical solution is that the resistance of the heating rod increases stepwise from the upper end to the lower end along the axial direction.

[0007] A further technical solution is that the rod diameter of the heating rod increases stepwise from the lower end to the upper end along the axial direction.

[0008] A further technical solution is that each group of heating rods includes 1, 2, 3 or 4 heating rods.

[0009] A further technical solution is that all the heating rods are arranged in parallel and evenly, and the distance between every two adjacent heating rods is equal.

[0010] Its further technical solution is that it also includes a first clamping block, the first clamping block is provided with a first groove; the lower connecting plate is provided with a first limiting groove, and the side wall of the first limiting groove is provided with a second groove; the first groove and the second groove together constitute a first cavity for clamping the lower end of the heating rod after the first clamping block and the first limiting groove are enclosed and fixed; the bottom of the first limiting groove is provided with a first through hole, and the lower end of the heating rod passes through the first cavity and enters the first through hole.

[0011] A further technical solution is that the first clamping block is fixed to the first limiting groove by bolts.

[0012] Its further technical solution is that it also includes a second clamping block, the second clamping block is provided with a third groove; the upper connecting plate is provided with a second limiting groove, and the side wall of the second limiting groove is provided with a fourth groove; the third groove and the fourth groove together constitute a second cavity for clamping the upper end of the heating rod after the second clamping block and the second limiting groove are enclosed and fixed; the bottom of the second limiting groove is provided with a second through hole, and the upper end of the heating rod passes through the second through hole into the second cavity.

[0013] A further technical solution is that the second clamping block is fixed to the second limiting groove by bolts.

[0014] A further technical solution is that the six heating components are connected end to end to form a cylindrical structure or a hexagonal tube structure.

[0015] Its further technical solution is that the graphite heater is powered by a three-phase power supply, and the three-phase power supply includes a U-phase output terminal, a V-phase output terminal and a W-phase output terminal; the U-phase output terminal is respectively connected to the U1 electrode and the U2 electrode, the V-phase output terminal is respectively connected to the V1 electrode and the V2 electrode, and the W-phase output terminal is respectively connected to the W1 electrode and the W2 electrode; the six heating components connected end to end are the first heating component, the second heating component, the third heating component, the fourth heating component, the fifth heating component and the sixth heating component in sequence; the U1 electrode is arranged on the upper connecting plate of the first heating component, the V1 electrode is arranged on the upper connecting plate of the second heating component, the W1 electrode is arranged on the upper connecting plate of the third heating component, the U2 electrode is arranged on the upper connecting plate of the fourth heating component, the V2 electrode is arranged on the upper connecting plate of the fifth heating component, and the W2 electrode is arranged on the upper connecting plate of the sixth heating component.

[0016] A further technical solution is that the upper connecting plate, the lower connecting plate, the heating rod, the first clamping block, the second clamping block and the bolts are all made of isostatic graphite.

[0017] Compared with the prior art, the technical effects that can be achieved by the utility model include:

[0018] The utility model provides a double-row graphite heater with uniform axial temperature gradient, and the heating rods are vertically connected. The resistance of the heating rods increases stepwise from the upper end to the lower end along the axial direction, which not only ensures the same resistance value between single rods, but also increases the resistance in the axial direction, so that the current changes linearly from bottom to top, and the electric heat also increases linearly. In the flow of the atmosphere from bottom to top, the temperature increases gradually and orderly, causing the relevant atmosphere to react from shallow to deep, ensuring the atmosphere reaction throughout the process. The heater provided by the utility model has a uniform temperature field in the horizontal direction and realizes gradient heating in the radial direction, which solves the problem that the heater has no gradient in the temperature field, and has reacted completely in the first half but not in the second half. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 A schematic diagram of the structure of a double-row graphite heater with uniformly variable axial temperature gradient provided by an embodiment of the utility model;

[0021] Figure 2 It is a structural schematic diagram of the heating rod;

[0022] Figure 3 It is a structural schematic diagram of the connection between the upper end of the heating rod and the upper connecting plate;

[0023] Figure 4 is a structural schematic diagram of the upper connecting plate;

[0024] Figure 5 is a structural schematic diagram of the lower connecting plate;

[0025] Figure 6 is a schematic structural diagram of a first clamping block;

[0026] Figure 7 A schematic diagram of the circuit connection of a double-row graphite heater with uniformly variable axial temperature gradient provided in an embodiment of the utility model.

[0027] Reference numerals

[0028] Graphite heater 100, upper connecting plate 11, second limiting groove 111, fourth groove 112, second through hole 113, lower connecting plate 12, first limiting groove 121, second groove 122, first through hole 123, heating rod 13, upper end 131, lower end 132, first clamping block 14, first groove 141, second clamping block 15, third groove 151, bolt hole 16, bolt 17, V1 electrode, V2 electrode, U1 electrode, U2 electrode, W1 electrode, W2 electrode, load R. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments. Similar component numbers in the drawings represent similar components. Obviously, the embodiments to be described below are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0030] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0031] It should also be understood that the terms used in this utility model embodiment specification are only for the purpose of describing specific embodiments and are not intended to limit the utility model embodiments. As used in the utility model embodiment specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0032] See also Figure 1-6 The embodiment of the utility model provides a double-row graphite heater with uniform axial temperature gradient. As can be seen from the figure, the graphite heater 100 includes 6 heating components connected end to end, and the heating components include an upper connecting plate 11, a lower connecting plate 12 and 2 groups of heating rods 13; each lower connecting plate 12 is connected to the lower ends of the 2 groups of heating rods 13, and the upper ends of the second group of heating rods 13 of the previous lower connecting plate 12 and the upper ends of the first group of heating rods 13 of the next lower connecting plate 12 are connected to the same upper connecting plate 11; the upper connecting plate 11 of the next heating component is connected to the upper ends of the second group of heating rods 13 of the lower connecting plate 12 of the previous heating component, so that the 6 heating components are connected end to end into a whole. Among them, an electrode is provided between the 2 groups of heating rods 13 located on the upper connecting plate 11; the resistance of the heating rod 13 increases stepwise from the upper end 131 to the lower end 132 along the axial direction.

[0033] The double-row graphite heater with uniform axial temperature gradient provided in this embodiment has a vertically connected heating rod 13, and the resistance of the heating rod 13 increases stepwise from the upper end 131 to the lower end 132 along the axial direction, so that the current change increases linearly from bottom to top, and the electric heat also increases linearly. In the flow of the atmosphere from bottom to top, the temperature increases gradually and orderly, causing the relevant atmosphere reaction to go from shallow to deep, ensuring the atmosphere reaction throughout the process. The heater provided by the utility model has a uniform temperature field in the horizontal direction and realizes gradient heating in the radial direction, which solves the problem that the heater has no gradient in the temperature field, and has reacted completely in the first half but not in the second half.

[0034] Please continue to see Figure 2 In this embodiment, the rod diameter of the heating rod 13 increases stepwise from the lower end 132 to the upper end 131 along the axial direction.

[0035] For example, in this embodiment, the total length of the heating rod 13 is 1600 mm, the diameter of the upper end 131 of the heating rod 13 is 50 mm, and the diameter of the lower end 132 is 40 mm. The heating rod 13 can be divided into 5 sections according to the requirements, and the gradient of the diameter change of each section is 2 mm.

[0036] In other embodiments, the heating rod can be divided into 10 sections radially according to needs, and the gradient of the rod diameter change in each section is 1 mm.

[0037] It can be understood that, according to the actual setting of the temperature field, the lengths of the heating rods 13 with different rod diameters can be the same or different; and the structure of each heating rod 13 is the same.

[0038] In some embodiments, each group of heating rods 13 includes 1, 2, 3 or 4 heating rods 13. For example, in this embodiment, each group of heating rods 13 includes 2 heating rods 13.

[0039] It can be understood that all the heating rods 13 are arranged in parallel and evenly, and the distance between each two adjacent heating rods 13 is equal, so as to ensure that the resistance between single rods is the same. After power is turned on, the load resistance is equal and the phase current is balanced, which better ensures the stability of electrical operation.

[0040] Please continue to see Figure 5-6 The heater provided in this embodiment also includes a first clamping block 14, which is provided with a first groove 141; the lower connecting plate 12 is provided with a first limiting groove 121, and the side wall of the first limiting groove 121 is provided with a second groove 122; the first groove 141 and the second groove 122 jointly constitute a first cavity for clamping the lower end 132 of the heating rod 13 after the first clamping block 14 and the first limiting groove 121 are enclosed and fixed; the bottom of the first limiting groove 121 is provided with a first through hole 123, and the lower end 132 of the heating rod 13 passes through the first cavity and enters the first through hole 123.

[0041] In a specific embodiment, the first clamping block 14 is provided with two bolt holes 16, and the side wall of the first limiting groove 121 is provided with two matching bolt holes 16 for screwing in bolts 17, and the first clamping block 14 is fixed to the first limiting groove 121 by bolts 17. The bolts 17 are carbon-carbon bolts, specifically bolts with latches.

[0042] Please continue to see Figure 3 and Figure 4 The heater provided in this embodiment also includes a second clamping block 15, and the second clamping block 15 is provided with a third groove 151; the upper connecting plate 11 is provided with a second limiting groove 111, and the side wall of the second limiting groove 111 is provided with a fourth groove 112; the third groove 151 and the fourth groove 112 jointly constitute a second cavity for clamping the upper end 131 of the heating rod 13 after the second clamping block 15 and the second limiting groove 111 are enclosed and fixed; the bottom of the second limiting groove 111 is provided with a second through hole 113, and the upper end 131 of the heating rod 13 passes through the second through hole 113 to enter the second cavity.

[0043] In one embodiment, the second clamping block 15 is provided with two bolt holes 16, and the side wall of the second limiting groove 121 is also provided with two matching bolt holes 16 for screwing in bolts 17, and the second clamping block 15 is fixed to the second limiting groove 111 by bolts 17. The bolts 17 are carbon-carbon bolts, specifically bolts with latches.

[0044] It can be understood that the provision of the first through hole 123 and the second through hole 113 helps to limit the end of the heating rod 13 and prevent deviation.

[0045] In other embodiments, for example, in this embodiment, the first clamping block 14 and the first limiting groove 121 , and the second clamping block 15 and the second limiting groove 111 are both provided with positioning holes to ensure accurate alignment of the two.

[0046] The double-row graphite heater with uniform axial temperature gradient provided by the embodiment of the utility model optimizes the fixing method of the heating rod 13, adopts its own clamping structure, and uses a clamping block to clamp the end of the heating rod 13 to the connecting plate to ensure its homogeneous deformation without stress generation.

[0047] In this embodiment, the upper connecting plate 11, the lower connecting plate 12, the heating rod 13, the first clamping block 14, the second clamping block 15 and the bolts are all made of isostatic graphite.

[0048] Please continue to see Figure 1 In other of the above embodiments, the six heating components are connected end to end to form a cylindrical structure or a hexagonal tubular structure.

[0049] In this embodiment, the six heating components are connected end to end to form a cylindrical structure.

[0050] See also Figure 1 and Figure 7 The graphite heater provided in this embodiment is powered by a three-phase power supply, and the three-phase power supply includes a U-phase output terminal, a V-phase output terminal and a W-phase output terminal; the U-phase output terminal is respectively connected to the U1 electrode and the U2 electrode, the V-phase output terminal is respectively connected to the V1 electrode and the V2 electrode, and the W-phase output terminal is respectively connected to the W1 electrode and the W2 electrode; the six heating components connected end to end are the first heating component, the second heating component, the third heating component, the fourth heating component, the fifth heating component and the sixth heating component in sequence; the U1 electrode is arranged on the upper connecting plate of the first heating component, the V1 electrode is arranged on the upper connecting plate of the second heating component, the W1 electrode is arranged on the upper connecting plate of the third heating component, the U2 electrode is arranged on the upper connecting plate of the fourth heating component, the V2 electrode is arranged on the upper connecting plate of the fifth heating component, and the W2 electrode is arranged on the upper connecting plate of the sixth heating component.

[0051] Understandably, Figure 7 In the embodiment, the load R connected to each electrode is a heating component.

[0052] In this embodiment, the two electrodes output from the same-phase output end are respectively located on the two upper connecting plates on the opposite sides of the cylindrical structure. This structure shares the current of the heating component under the phase voltage, reduces the current density of a single heating rod, and helps to improve the safety of electrical operation.

[0053] It can be understood that in order to ensure the current balance between phases, the six electrodes are respectively located at the vertices of the regular hexagon inscribed in the circle corresponding to the cylindrical structure.

[0054] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0055] The above is a specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the utility model, and these modifications or replacements should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.

Claims

1. A double-row graphite heater with uniformly variable axial temperature gradient, characterized in that: The invention comprises 6 heating components connected end to end, wherein the heating components comprise an upper connecting plate, a lower connecting plate and 2 groups of heating rods; each lower connecting plate is connected to the lower ends of the 2 groups of heating rods, the upper ends of the second group of heating rods of the previous lower connecting plate and the upper ends of the first group of heating rods of the next lower connecting plate are connected to the same upper connecting plate; an electrode is arranged between the 2 groups of heating rods of the upper connecting plate; the resistance of the heating rod increases stepwise from the upper end to the lower end along the axial direction.

2. The double-row graphite heater with uniformly variable axial temperature gradient according to claim 1, characterized in that: The rod diameter of the heating rod increases stepwise from the lower end to the upper end along the axial direction.

3. The double-row graphite heater with uniformly variable axial temperature gradient according to claim 1, characterized in that: Each group of heating rods includes 1, 2, 3 or 4 heating rods.

4. The double-row graphite heater with uniformly variable axial temperature gradient according to any one of claims 1 to 3, characterized in that: All the heating rods are arranged in parallel and evenly, and the distance between every two adjacent heating rods is equal.

5. The double-row graphite heater with uniformly variable axial temperature gradient according to claim 1, characterized in that: It also includes a first clamping block, which is provided with a first groove; the lower connecting plate is provided with a first limiting groove, and the side wall of the first limiting groove is provided with a second groove; the first groove and the second groove together constitute a first cavity for clamping the lower end of the heating rod after the first clamping block and the first limiting groove are enclosed and fixed; the bottom of the first limiting groove is provided with a first through hole, and the lower end of the heating rod passes through the first cavity and enters the first through hole.

6. The double-row graphite heater with uniformly variable axial temperature gradient according to claim 5, characterized in that: The first clamping block is fixed to the first limiting groove by bolts.

7. The double-row graphite heater with uniformly variable axial temperature gradient according to claim 1, characterized in that: It also includes a second clamping block, which is provided with a third groove; the upper connecting plate is provided with a second limiting groove, and the side wall of the second limiting groove is provided with a fourth groove; the third groove and the fourth groove together constitute a second cavity for clamping the upper end of the heating rod after the second clamping block and the second limiting groove are enclosed and fixed; a second through hole is provided at the bottom of the second limiting groove, and the upper end of the heating rod passes through the second through hole into the second cavity.

8. The double-row graphite heater with uniformly variable axial temperature gradient according to claim 7, characterized in that: The second clamping block is fixed to the second limiting groove by bolts.

9. The double-row graphite heater with uniformly variable axial temperature gradient according to claim 1, characterized in that: The six heating components are connected end to end to form a cylindrical structure or a hexagonal tube structure.

10. The double-row graphite heater with uniformly variable axial temperature gradient according to claim 9, characterized in that: The graphite heater is powered by a three-phase power supply, which includes a U-phase output terminal, a V-phase output terminal and a W-phase output terminal; the U-phase output terminal is respectively connected to the U1 electrode and the U2 electrode, the V-phase output terminal is respectively connected to the V1 electrode and the V2 electrode, and the W-phase output terminal is respectively connected to the W1 electrode and the W2 electrode; the six heating components connected end to end are the first heating component, the second heating component, the third heating component, the fourth heating component, the fifth heating component and the sixth heating component in sequence; the U1 electrode is arranged on the upper connecting plate of the first heating component, the V1 electrode is arranged on the upper connecting plate of the second heating component, the W1 electrode is arranged on the upper connecting plate of the third heating component, the U2 electrode is arranged on the upper connecting plate of the fourth heating component, the V2 electrode is arranged on the upper connecting plate of the fifth heating component, and the W2 electrode is arranged on the upper connecting plate of the sixth heating component.

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