Double-layer hot wire device for preparing large diamond coating cutter

Abstract

The invention provides a double-layer hot wire device for preparing a large diamond coating cutter, which comprises two negative electrodes and four positive electrodes, the two negative electrodes are homologous, the four positive electrodes are homologous, two negative electrode plates are arranged between the two negative electrodes, the two negative electrode plates are arranged up and down, two of the four positive electrodes are high, and the other two of the four positive electrodes are high. And the other two positive electrodes are low, and the two high positive electrodes are close to the negative electrodes. According to the double-layer hot wire device for preparing the large diamond coating cutting tool, the problem that the temperature difference of the cutting tool in the direction perpendicular to the hot wires is too large is effectively solved through the double-layer hot wire layout, the relationship between the diameters of the hot wires and the resistance is utilized, the hot wire layout of different diameters is adopted, and the cutting tool is manufactured. Two layers of hot wire arrays with different temperatures can be achieved only through a single electrode, and the upper layer and the lower layer adopt hot wires with different lengths, so that collision between heavy hammers providing gravity can be avoided.

Description

Technical Field

[0001] The invention relates to the technical field of hot wire chemical vapor deposition, in particular to a double-layer hot wire device for preparing large diamond coating cutting tools. Background Art

[0002] Diamond has many excellent mechanical, thermal, acoustic, optical, electrical, and chemical properties. It has been applied and industrialized in many fields. However, naturally mined diamonds are not only limited in quantity, but also very expensive. Therefore, artificial synthesis of diamonds has become a hot topic today, and there are many ways to synthesize it. Hot wire chemical vapor deposition is a chemical vapor deposition technology. Its principle is to apply voltage to both ends of the hot wire to generate current, so that it generates heat and generates high temperature to decompose carbon-containing gas, so that the carbon atoms in it are gradually deposited on the substrate to form a thin film of diamond phase. The main body of the device generally used is a pure copper workbench with electrodes on both sides. Several hot wires that can be powered are connected to the electrodes. The material is generally tantalum. The substrate material to be plated is placed under the parallel array composed of multiple hot wires. In addition to the main body of the device, a double-layer bell jar is also required, and its main function is to create a closed space for reaction gas. Since the working temperature of the hot wire is about 2000℃ and the temperature of the substrate is about 900℃, water cooling equipment is also required. Generally, water cooling is introduced through two structures, one is the pure copper workbench mentioned above, which is mainly used to dissipate heat for the substrate, and the other is a double-layer bell jar, which is mainly used to dissipate heat for the bell jar.

[0003] However, there are problems with the current technical structure, because the hot wires are arranged in parallel, and the coated tools are placed perpendicular to the array. The temperature is mainly transmitted in the form of thermal radiation, and with the help of water cooling equipment, the overall temperature difference of the tool is very large. The position of the cutter head is relatively close to the hot wire, and the temperature is high, while the position of the blade is relatively far from the hot wire, and the temperature is relatively low. The temperature has a great influence on the growth of diamond film, so the diamond-coated tools produced by this hot wire layout method often have good blade quality and poor blade quality.

[0004] This case was created to solve the above problems. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] The object of the present invention is to provide a double-layer hot wire device for preparing large diamond-coated cutting tools, so as to solve the problems raised in the above-mentioned background technology.

[0007] (II) Technical solution

[0008] To achieve the above objectives, the present invention is implemented through the following technical scheme: a double-layer hot wire device for preparing large diamond-coated cutting tools, comprising two negative electrodes and four positive electrodes, the two negative electrodes are of the same source, the four positive electrodes are of the same source, two negative electrode plates are arranged between the two negative electrodes, the two negative electrode plates are arranged one above and one below, two of the four positive electrodes are high, and the other two are low, and the two high positive electrodes are close to the negative electrode.

[0009] Preferably, a molybdenum rod is provided between the two high positive electrodes and between the two low positive electrodes, a hot wire is connected between the molybdenum rod and the negative electrode plate, and two layers of parallel hot wires are formed between the two negative electrode plates and the two molybdenum rods.

[0010] Preferably, the two layers of hot wires have different lengths and thicknesses, the hot wires in the upper layer are shorter than those in the lower layer, and the hot wires in the upper layer have larger diameters than those in the lower layer.

[0011] Preferably, one end of the hot wire is connected to the negative electrode plate, and the other end of the hot wire is wrapped around the molybdenum rod and connected to a weight.

[0012] Preferably, a square bracket is provided below the weight connected to the upper hot wire, a weight hole is provided on the top surface of the square bracket, and a contact switch is provided in the weight hole.

[0013] Preferably, a disconnect mechanism is provided on the same source of the four positive electrodes, the disconnect mechanism is connected to the square bracket, the contact switch is electrically connected to the disconnect mechanism, and the electrical connection wiring is carried out inside the square bracket.

[0014] Preferably, the square bracket and the disconnecting mechanism are both made of high temperature resistant materials.

[0015] (III) Beneficial effects

[0016] After adopting the above technical scheme, the present invention has the following advantages compared with the prior art: the present invention is a double-layer hot wire device for preparing large diamond coated tools, and a double-layer hot wire is arranged on the electrode. The purpose of the upper hot wire is to decompose the gas, so a higher temperature is required, and the function of the lower hot wire is mainly to maintain the temperature stability of the substrate, reduce the difference in the vertical direction and strive to be consistent, so the temperature cannot be as high as the upper hot wire. By changing the length and diameter specifications of the upper and lower hot wires, they are connected to the same electrode. Under the condition of keeping the voltage consistent, the temperature of the hot wire with a large diameter and a short length can be higher than that of the hot wire with a small diameter and a long length, so that the purpose of separating the double-layer hot wire with one electrode is achieved. Compared with the traditional single-layer hot wire layout, the double-layer hot wire layout effectively solves the problem of excessive temperature difference of the tool in the direction perpendicular to the hot wire, and utilizes the relationship between the hot wire diameter and the resistance, adopts the hot wire layout with different diameters, and realizes that only a single electrode is used to achieve two layers of hot wire arrays with different temperatures, and the upper and lower layers use hot wires of different lengths, which can avoid collision between the heavy hammers providing gravity. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the structure of the present invention;

[0018] Figure 2 Schematic diagram of diamond coating on traditional cutting tools (electrode structure is simplified);

[0019] In the figure: 1 negative electrode, 2 positive electrode, 3 negative electrode plate, 4 molybdenum rod, 5 hot wire, 6 weight, 7 substrate, 8 square bracket, 9 weight hole, 10 disconnection mechanism. DETAILED DESCRIPTION

[0020] The present invention will be further described in detail below through the accompanying drawings and examples.

[0021] The embodiment of the present invention provides a double-layer hot wire device for preparing a large diamond-coated tool, such as Figure 1 As shown, it includes two negative electrodes 1 and four positive electrodes 2. The two negative electrodes 1 are of the same source, the four positive electrodes 2 are of the same source, two negative electrode plates 3 are arranged between the two negative electrodes 1, the two negative electrode plates 3 are arranged one above and one below, two of the four positive electrodes 2 are high, and the other two are low, and the two high positive electrodes 2 are close to the negative electrodes 1.

[0022] Molybdenum rods 4 are provided between the two high positive electrodes 2 and between the two low positive electrodes 2. Hot wires 5 are connected between the molybdenum rods 4 and the negative electrode plates 3. Two layers of parallel hot wires 5 are formed between the two negative electrode plates 3 and the two molybdenum rods 4. A double layer of hot wires 5 is arranged between the negative electrode 1 and the positive electrode 2. The purpose of the upper hot wire 5 is to decompose the gas, so a higher temperature is required, and the function of the lower hot wire is mainly to maintain the temperature stability of the substrate, reduce the difference in the vertical direction and strive for consistency, so the temperature cannot be as high as the upper hot wire. The tool passes through the lower hot wire 5 but not the upper hot wire 5. When the tool temperature is more stable when passing through the lower hot wire 5.

[0023] The lengths and thicknesses of the two layers of hot wires 5 are different. The length of the upper layer of hot wires 5 is shorter than that of the lower layer of hot wires 5, and the diameter of the upper layer of hot wires 5 is larger than that of the lower layer of hot wires 5. The wire spacings of the two layers of hot wires can be the same or different, depending on the situation. By changing the length and diameter specifications of the upper and lower layers of hot wires 5 and connecting them to the same voltage, when the voltage remains the same, the temperature of the hot wire 5 with a large diameter and a short length can be higher than that of the hot wire 5 with a small diameter and a long length, thereby achieving the purpose of separating a double layer of hot wires 5 with one electrode. Compared with the traditional single-layer hot wire layout, the double-layer hot wire 5 layout effectively solves the problem of excessive temperature difference of the tool in the direction perpendicular to the hot wire 5, and utilizes the relationship between the diameter and resistance of the hot wire 5 and adopts a layout of hot wires 5 with different diameters, thereby achieving two layers of hot wire 5 arrays with different temperatures using only a single electrode.

[0024] One end of the hot wire 5 is connected to the negative electrode plate 3, and the other end of the hot wire 5 is passed around the molybdenum rod 4 and connected to the weight 6. The upper and lower layers use hot wires 5 of different lengths to avoid collision between the weights 6 providing gravity.

[0025] Reference Figure 1 A square bracket 8 is provided below the weight 6 connected to the upper hot wire 5, and a weight hole 9 is provided on the top surface of the square bracket 8. A contact switch is provided in the weight hole 9. Since the temperature of the upper hot wire 5 is higher, there is a hidden danger of melting. Therefore, a square bracket 8 is provided below the weight 6 connected to the upper hot wire 5, and the weight hole 6 thereon corresponds one by one to the upper weight 6. Once a hot wire 5 in the upper layer melts, the weight 6 connected to it will fall into the corresponding weight hole 9 and trigger the contact switch at the same time.

[0026] Reference Figure 1A disconnecting mechanism 10 is provided on the same source of the four positive electrodes 2, and the disconnecting mechanism 10 is connected to the square bracket 8. The contact switch is electrically connected to the disconnecting mechanism 10. When one electric shock switch is activated, the disconnecting mechanism 10 immediately sounds an alarm. When more than one contact switch is activated, the disconnecting mechanism 10 will immediately and automatically disconnect the positive power supply line (the contact switch and the disconnecting mechanism are both prior art and will not be repeated here) to ensure safety. The electrical connection wiring is carried out inside the square bracket 8. The square bracket 8 and the disconnecting mechanism 10 are both made of high temperature resistant materials to ensure that they will not be damaged during operation.

[0027] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A double-layer hot wire device for preparing large diamond-coated cutting tools, characterized in that: The invention comprises two negative electrodes (1) and four positive electrodes (2), wherein the two negative electrodes (1) are of the same source, the four positive electrodes (2) are of the same source, two negative electrode plates (3) are arranged between the two negative electrodes (1), the two negative electrode plates (3) are arranged one above the other, two of the four positive electrodes (2) are high and the other two are low, and the two high positive electrodes (2) are close to the negative electrode (1).

2. A double-layer hot wire device for preparing large diamond-coated cutting tools according to claim 1, characterized in that: A molybdenum rod (4) is provided between the two high positive electrodes (2) and between the two low positive electrodes (2); a hot wire (5) is connected between the molybdenum rod (4) and the negative electrode plate (3); and two layers of parallel hot wires (5) are formed between the two negative electrode plates (3) and the two molybdenum rods (4).

3. A double-layer hot wire device for preparing large diamond-coated cutting tools according to claim 2, characterized in that: The two layers of hot wires (5) have different lengths and thicknesses; the hot wires (5) of the upper layer are shorter than the hot wires (5) of the lower layer, and the hot wires (5) of the upper layer have larger diameters than the hot wires (5) of the lower layer.

4. A double-layer hot wire device for preparing large diamond-coated cutting tools according to claim 3, characterized in that: One end of the hot wire (5) is connected to the negative electrode plate (3), and the other end of the hot wire (5) is wound around the molybdenum rod (4) and is connected to a weight (6).

5. A double-layer hot wire device for preparing large diamond-coated cutting tools according to claim 4, characterized in that: A square bracket (8) is arranged below the weight (6) connected to the upper hot wire (5), a weight hole (9) is arranged on the top surface of the square bracket (8), and a contact switch is arranged in the weight hole (9).

6. A double-layer hot wire device for preparing large diamond-coated cutting tools according to claim 5, characterized in that: A disconnection mechanism (10) is provided on the same source of the four positive electrodes (2), the disconnection mechanism (10) is connected to the square bracket (8), the contact switch is electrically connected to the disconnection mechanism (10), and the electrical connection wiring is carried out inside the square bracket (8).

7. A double-layer hot wire device for preparing large diamond-coated cutting tools according to claim 6, characterized in that: The square bracket (8) and the disconnecting mechanism (10) are both made of high temperature resistant materials.

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