CN104867801B - Inductively coupled plasma spray gun and plasma device - Google Patents

Abstract

The invention discloses an inductively coupled plasma spray gun and plasma equipment, wherein the inductively coupled plasma spray gun includes a discharge chamber, a gas introduction device, a cooling device and an inductance coil; the discharge chamber is surrounded by a first hollow pipe, and the second A hollow tube is a silicon nitride tube or a silicon carbide tube; the gas introduction device communicates with the discharge chamber; the cooling device includes a second hollow tube, a coolant inlet component and a coolant outlet component, and the second hollow tube is surrounded by the first hollow tube , and there is a first gap between the inner side wall of the second hollow pipe and the outer side wall of the first hollow pipe, the coolant inlet component and the coolant outlet component are both in communication with the first gap; the inductance coil is arranged on the second hollow tube outside. The invention improves the stability of the inductively coupled plasma spray gun during use, effectively avoids the rupture caused by high temperature, satisfies the requirement of continuous production, and reduces potential safety hazards.

Description

Inductively coupled plasma torch and plasma equipment

technical field

The invention relates to the field of plasma technology, in particular to an inductively coupled plasma torch and plasma equipment using the same.

Background technique

Plasma is a form of matter mainly composed of free electrons and charged ions. It is called the fourth state of matter and is widely used in technical fields such as smelting, coating, crystal growth, spraying and welding.

Plasma can be produced naturally (such as the northern lights and lightning), or artificially. The methods of artificially generating plasma mainly include: DC arc discharge method, AC power frequency discharge method, high frequency induction discharge method, glow discharge method and combustion method.

Among them, the equipment used to generate plasma by the high-frequency induction discharge method is usually an inductively coupled plasma torch. The current inductively coupled plasma spray gun has poor heat resistance and is prone to breakage during use, which not only cannot meet the needs of continuous production, but also has great potential safety hazards.

Contents of the invention

The invention provides an inductively coupled plasma spray gun and plasma equipment with good heat resistance.

To achieve the above object, the present invention adopts the following technical solutions:

An inductively coupled plasma torch comprising

A discharge chamber, the discharge chamber is surrounded by a first hollow pipe, and the first hollow pipe is a silicon nitride pipe or a silicon carbide pipe;

a gas introduction device, the gas introduction device communicates with the discharge chamber;

A cooling device, the cooling device includes a second hollow pipe, a coolant inlet component and a coolant outlet component, the second hollow pipe surrounds the outside of the first hollow pipe, and the inside of the second hollow pipe There is a first gap between the wall and the outer side wall of the first hollow pipe, and both the coolant inlet component and the coolant outlet component communicate with the first gap;

An induction coil, the induction coil is arranged on the outside of the second hollow pipe.

In one of the embodiments, the gas introduction device includes a reaction gas introduction pipe, and the reaction gas introduction pipe is provided with an intake channel and a coolant circulation channel, and the coolant circulation channel is arranged around the intake channel , the air intake channel communicates with the discharge chamber.

In one of the embodiments, the coolant circulation channel includes a first cooling channel and a second cooling channel communicated with each other;

The first cooling passage, the second cooling passage are arranged coaxially with the air intake passage, the first cooling passage is surrounded by the outside of the air intake passage, and the second cooling passage is surrounded by the air intake passage. the outer side of the first cooling channel;

The first cooling channel is provided with a coolant inlet, and the second cooling channel is provided with a coolant outlet.

In one of the embodiments, the ratio of the cross-sectional area of the first cooling channel to the cross-sectional area of the intake channel is 2:1-4:1, and the ratio of the cross-sectional area of the first cooling channel to the The cross-sectional areas of the second cooling channels are equal.

In one of the embodiments, the gas introduction device further includes a plasma gas introduction component, and the plasma gas introduction component is provided with a radial gas guide port and a tangential gas guide port, and the radial gas guide port and the tangential gas guide port are both communicate with the discharge chamber.

In one of the embodiments, one end of the reaction gas introduction pipe is sleeved in the first hollow pipe, and there is a second gap between the outer wall of the reaction gas introduction pipe and the inner wall of the first hollow pipe. , both the radial air guide port and the tangential air guide port communicate with the discharge chamber through the second gap.

In one embodiment, the size of the second gap is 1mm˜5mm.

In one embodiment, the size of the first gap is 1mm˜10mm.

In one embodiment, the inner diameter of the first hollow pipe is 40 mm to 80 mm, and the thickness of the first hollow pipe is 1 mm to 3 mm.

In one embodiment, the inner diameter of the second hollow pipe is 48mm-90mm, and the thickness of the second hollow pipe is 2mm-4mm.

In one of the embodiments, both the coolant inlet component and the coolant outlet component are fixed on the outer side wall of the second hollow pipe, and the coolant inlet component is located at the bottom of the second hollow pipe end, the coolant outlet component is located at the top of the second hollow pipe.

In one of the embodiments, the inductively coupled plasma torch also includes a fixing part and an adjustment ring;

The reaction gas introduction pipe is fixed by the fixing member;

The top end of the reaction gas introduction pipe is radially provided with a protruding part, the adjustment ring is arranged between the protrusion and the fixing part, and the reaction gas introduction pipe is axially adjusted through the adjustment ring. Position adjustment.

A plasma device includes the inductively coupled plasma torch.

The beneficial effects of the present invention are as follows:

In the inductively coupled plasma torch and plasma equipment of the present invention, the discharge chamber is made of silicon nitride or silicon carbide material, which has good thermal conductivity and excellent high temperature resistance, which greatly improves the efficiency of inductively coupled plasma. The stability of the spray gun during use effectively avoids the rupture caused by high temperature, thereby meeting the needs of continuous production and reducing potential safety hazards; moreover, a cooling device is installed around the first hollow pipe to cool down, further preventing Burnout or rupture of the first hollow pipe 110 improves the safety performance; in addition, the inductively coupled plasma torch uses an inductive coil for inductive coupling, which avoids the use of electrodes and reduces material cost and material pollution.

Description of drawings

Fig. 1 is the structural representation of an embodiment of the inductively coupled plasma torch of the present invention;

Fig. 2 is an enlarged view of part A in Fig. 1 .

detailed description

Specific embodiments of the present invention will be described in detail below. It should be understood that the specific embodiments described here are only used to illustrate and explain the present invention, and are not intended to limit the present invention. It should be noted that the location words in the present invention, such as bottom end, top end, etc., all refer to the placement positions in FIG. 1 .

Referring to FIG. 1 and FIG. 2 , the present invention provides an inductively coupled plasma torch, which includes a discharge chamber 100 , a gas introduction device 200 , a cooling device 300 and an induction coil 400 . The plasma torch is mainly used to generate plasma, and is usually used in conjunction with other devices to complete processes such as smelting, coating, crystal growth, spraying or welding.

Wherein, the discharge chamber 100 is a chamber for generating plasma, which is surrounded by a first hollow tube 110, the first hollow tube 110 is a silicon nitride tube or a silicon carbide tube; one end of the gas introduction device 200 is connected to the discharge chamber 100 Communication, when working, the other end of the gas introduction device 200 is connected with the gas source, and is used to introduce gas into the discharge chamber 100. The gas introduced usually includes reaction gas and plasma gas, and the specific type depends on the process requirements; the cooling device 300 Comprising a second hollow pipe 310 , a coolant inlet component 320 and a coolant outlet component 330 , the second hollow pipe 310 surrounds the outside of the first hollow pipe 110 , and the inner wall of the second hollow pipe 310 is in contact with the first hollow pipe 110 There is a first gap 340 between the outer sidewalls of the coolant inlet assembly 320 and the coolant outlet assembly 330 are in communication with the first gap 340, when working, the coolant first flows from the coolant inlet assembly 320 into the first gap 340, and Heat exchange occurs on the tube wall of the discharge chamber 100, taking away part of the heat generated in the discharge chamber 100, and then flows out from the coolant outlet assembly 330; the inductance coil 400 is arranged on the outside of the second hollow pipe 310, and can be directly wound on the second hollow pipe. On the outer wall of the pipe 310, the inductance coil 400 communicates with the radio frequency power supply during the working process, and a large induced voltage is generated through inductive coupling, so that the plasma gas in the discharge chamber 100 is discharged to generate plasma. Preferably, the inductance coil 400 Made of copper tube, the number of turns is preferably 3-6 turns.

It should be noted that the coolant in the present invention can be cooling water or other cooling liquids, or cooling gas, preferably cooling water; the plasma gas in the present invention refers to the process gas, which is ionized in the discharge chamber 100 The plasma is usually argon or helium; the reactive gas refers to the gas that plays a substantial role in the process, and is ionized into ions in the discharge chamber 100 , and finally forms an ion flow together with the plasma and flows out of the spray gun.

In the inductively coupled plasma torch of the present invention, the discharge chamber 100 is made of silicon nitride or silicon carbide material, which itself has good thermal conductivity and excellent high temperature resistance, thereby greatly improving the inductive coupling The stability of the plasma spray gun during use effectively avoids the rupture caused by high temperature, thereby meeting the needs of continuous production and reducing potential safety hazards; moreover, a cooling device 300 is installed around the first hollow pipe 110 to cool down , which further prevents the first hollow pipe 110 from being burnt out or cracked, and improves the safety performance. At the same time, the cooling device 300 can also cool down the inductance coil 400, thereby improving the inductive coupling efficiency; in addition, the inductively coupled plasma spray gun adopts The induction coil 400 performs inductive coupling, avoids the use of electrodes, and reduces material cost and material pollution.

Preferably, in the above-mentioned inductively coupled plasma torch, the size of the first gap 340 is 1mm˜10mm. Within the range of the gap, the flow rate of the coolant is relatively large, which can effectively exchange heat and give full play to the cooling effect of the coolant.

Since the material of the first hollow pipe 110 is silicon nitride or silicon carbide, the inner diameter of the first hollow pipe 110 is preferably 40 mm to 80 mm, and the thickness is preferably 1 mm to 3 mm based on the thermal conductivity, expansion coefficient and plasma generation conditions of the material. , within this numerical range, the first hollow pipe 110 has more excellent heat resistance and thermal conductivity, which effectively prevents the first hollow pipe 110 from cracking and improves safety performance.

The inner diameter of the second hollow pipe 310 is set according to the inner diameter of the first hollow pipe 110 , preferably 48mm-90mm, and the thickness of the second hollow pipe 310 is preferably 2mm-4mm. The present invention has no special requirements on the material of the second hollow tube 310, and it is preferably a quartz tube, which has lower price and higher chemical stability.

As a possible implementation mode, the gas introduction device 200 in the present invention includes a reaction gas introduction pipe 210, and the reaction gas introduction pipe 210 is provided with an air inlet channel 212 for introducing gas and a channel for reducing the temperature of the gas introduced. The coolant circulation channel 214 is arranged around the intake channel 212 , and the intake channel 212 communicates with the discharge chamber 100 . During operation, gas is passed into the air intake passage 212, and coolant is passed into the coolant circulation passage 214. The temperature of the gas decreases under the cooling effect of the coolant, and the temperature in the discharge chamber 100 can be lowered after entering the discharge chamber 100. , to further prevent the damage of the first hollow pipe 110 due to high temperature; meanwhile, the coolant in the coolant circulation channel 214 avoids the damage of the reaction gas introduction pipe 210 itself at high temperature, ensuring the smooth introduction of gas. In the present invention, the gas inlet channel 212 is generally used for introducing reaction gas.

Preferably, the coolant circulation channel 214 includes a first cooling channel 2142 and a second cooling channel 2144 that communicate with each other; Surrounded outside the intake passage 212 , the second cooling passage 2144 is disposed outside the first cooling passage 2142 ; the first cooling passage 2142 is provided with a coolant inlet, and the second cooling passage 2144 is provided with a coolant outlet. In this embodiment, through the arrangement of the two-layer cooling channel, the circulation time of the coolant in the channel is increased, and the circulation path of the coolant is extended, thereby improving the cooling efficiency and effectively preventing the gas introduction device 200 from being damaged due to excessive temperature. At the same time, the coolant inlet is set on the first cooling channel 2142 adjacent to the intake channel 212, and the coolant outlet is set on the second cooling channel 2144 outside. The cooling effect of the gas, and effectively reduce the heat exchange between the coolant and the external environment, thereby improving the effective heat exchange rate of the coolant.

It should be noted that the above-mentioned coolant circulation channel 214 is not limited to the first cooling channel 2142 and the second cooling channel 2144 , and in other embodiments, it may also include more cooling channels.

More preferably, the ratio of the cross-sectional area of the first cooling passage 2142 to the cross-sectional area of the intake passage 212 is 2:1˜4:1. In this manner, the coolant can fully exchange heat with the reaction gas in the intake channel 212 , so that the reaction gas has a lower temperature when it enters the discharge chamber 100 , which is beneficial to the protection of the discharge chamber 100 and the control of the ionization rate. Further, the cross-sectional area of the first cooling channel 2142 is equal to the cross-sectional area of the second cooling channel 2144 . This method facilitates the control of the flow rate of the coolant, and enhances the uniformity of the overall cooling effect.

As a possible implementation, the gas introduction device 200 also includes a plasma gas introduction component 220, the plasma gas introduction component 220 is provided with a radial gas guide port 222 and a tangential gas guide port 224, and the radial gas guide port 222 and the tangential gas guide port 224 are connected with each other. The discharge chamber 100 is connected, and the plasma gas enters the discharge chamber 100 through the radial gas guide opening 222 and the tangential gas guide opening 224 . Wherein, the plasma gas runs in a straight line in the radial gas guide port 222, and the running direction is parallel to the radial direction (the radial direction of the first hollow pipe 110); ) running, the running direction is at a certain angle to the radial direction, preferably 30°-90°. The plasma gas introduced in this embodiment will cool and protect the first hollow pipe 110; at the same time, this embodiment adopts the combination of radial air intake and tangential air guide to feed plasma gas, which not only increases the The overall intake rate, and different intake directions will form a small cyclone, which is conducive to the convection between the gases, so that the mixing of the reaction gas and the plasma gas is more uniform.

Preferably, the radial gas guide port 222 is disposed above the tangential gas guide port 224 , and this position can further improve the uniformity of gas mixing.

It should be noted that, in other embodiments, the inductively coupled plasma torch of the present invention may not include the plasma gas introduction component 220 , and the plasma gas may be introduced into the discharge chamber 100 through the reactive gas introduction pipe 210 .

As shown in Figure 2, one end of the reaction gas introduction pipe 210 is sleeved in the first hollow pipe 110, there is a second gap 230 between the outer side wall of the reaction gas introduction pipe 210 and the inner side wall of the first hollow pipe 110, and the radial gas guide port Both the 222 and the tangential gas guide 224 communicate with the discharge chamber 100 through the second gap 230 . The plasma gas enters into the discharge chamber 100 through the second gap 230. Since the reaction gas introduction pipe 210 and the cooling device 300 are respectively arranged on both sides of the second gap 230, the plasma gas circulating in the second gap 230 can be Through the double cooling of the coolant in the reaction gas introduction pipe 210 and the coolant in the cooling device 300, the lower temperature plasma gas can cool the inner wall of the first hollow pipe 110, thereby greatly improving the safety of the spray gun performance. Preferably, the size of the second gap 230 is 1mm˜5mm.

Preferably, as a possible implementation, the coolant introduction assembly 320 and the coolant outlet assembly 330 are both fixed on the outer wall of the second hollow pipe 310 , and the coolant introduction assembly 320 is located at the bottom end of the second hollow pipe 310 , the coolant outlet assembly 330 is located at the top of the second hollow tube 310 . In this embodiment, the coolant flows to the first gap 340 through the coolant introduction component 320 at the bottom, and flows out through the coolant outlet component 330 at the top. Since the flow direction of the ion flow in the discharge chamber 100 is from top to bottom, The flow direction of the coolant is from bottom to top, and the convection method is beneficial to the improvement of heat exchange efficiency. Preferably, a support rod 500 is provided between the coolant introduction assembly 320 and the coolant outlet assembly 330 , and the coolant introduction assembly 320 and the coolant outlet assembly 330 are fixed by the support rod 500 .

Continuing to refer to FIG. 1 , the inductively coupled plasma torch further includes a fixing part 600 and an adjustment ring 700 . Wherein, the fixing member 600 is used for fixing the reaction gas introduction pipe 210, and plays the role of sealing the upper end of the discharge chamber 100 at the same time, usually, the fixing member 600 is located in the middle area of the reaction gas introduction pipe 210; The top end is provided with a protrusion in the radial direction, and the adjustment ring 700 is arranged between the protrusion and the fixed part 600. The reaction gas introduction pipe 210 can adjust the axial position through the adjustment ring 700, for example, by changing the adjustment ring 700 Adjust the axial position of the reaction gas introduction pipe 210 according to the height and the number.

In addition, the inductively coupled plasma torch of the present invention further includes a fixing plate 800 . When the torch is assembled, the first hollow pipe 110 is installed from the bottom of the torch and fixed by the fixing plate 800 . This method facilitates the installation and disassembly of the first hollow pipe 110 , and can be quickly replaced when the first hollow pipe 110 is damaged.

The invention improves the stability of the inductively coupled plasma spray gun during use, effectively avoids cracks caused by high temperature, meets the needs of continuous production, and reduces potential safety hazards; at the same time, each component in the inductively coupled plasma spray gun is separated Installation facilitates maintenance and replacement of parts.

In addition, the present invention also provides a plasma device, including the above-mentioned inductively coupled plasma torch. Wherein, the plasma equipment may be vacuum coating equipment, crystal growth equipment and the like. Due to the above-mentioned inductively coupled plasma spray gun, the plasma equipment of the present invention has stronger heat resistance, stability and higher work efficiency; and, in processes such as coating or crystal growth, the ion flow leaves the spray gun The diameter of the arc column formed after entering the deposition chamber is relatively large, and the reactant stays in the high temperature area for a long time, which can make the reaction more complete.

The above-mentioned embodiments only express several implementation modes of the present invention, and the descriptions thereof are relatively specific and detailed, but should not be construed as limiting the patent scope of the present invention. It should be pointed out that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims (11)

1. An inductively coupled plasma spray gun, characterized in that, comprising A discharge chamber, the discharge chamber is surrounded by a first hollow pipe, and the first hollow pipe is a silicon nitride pipe or a silicon carbide pipe; A gas introduction device, the gas introduction device communicates with the discharge chamber, the gas introduction device includes a reaction gas introduction pipe and a plasma gas introduction assembly, and the reaction gas introduction pipe is provided with an air intake channel and a coolant circulation channel , the coolant circulation channel is arranged around the air intake channel, the air intake channel communicates with the discharge chamber, the plasma gas introduction component is provided with a radial air guide port and a tangential air guide port, the radial guide port Both the gas port and the tangential gas guide are in communication with the discharge chamber; A cooling device, the cooling device includes a second hollow pipe, a coolant inlet component and a coolant outlet component, the second hollow pipe surrounds the outside of the first hollow pipe, and the inside of the second hollow pipe There is a first gap between the wall and the outer side wall of the first hollow pipe, and both the coolant inlet component and the coolant outlet component communicate with the first gap; An induction coil, the induction coil is arranged on the outside of the second hollow pipe. 2. The inductively coupled plasma torch according to claim 1, wherein the coolant circulation channel comprises a first cooling channel and a second cooling channel communicated with each other; The first cooling passage, the second cooling passage are arranged coaxially with the air intake passage, the first cooling passage is surrounded by the outside of the air intake passage, and the second cooling passage is surrounded by the air intake passage. the outer side of the first cooling channel; The first cooling channel is provided with a coolant inlet, and the second cooling channel is provided with a coolant outlet. 3. The inductively coupled plasma torch according to claim 2, wherein the ratio of the cross-sectional area of the first cooling passage to the cross-sectional area of the intake passage is 2:1˜4:1, The cross-sectional area of the first cooling channel is equal to the cross-sectional area of the second cooling channel. 4. The inductively coupled plasma torch according to claim 1, wherein one end of the reaction gas introduction pipe is sleeved in the first hollow pipe, and the outer wall of the reaction gas introduction pipe is in contact with the first hollow pipe. There is a second gap between inner sidewalls of a hollow pipe, and both the radial air guide port and the tangential air guide port communicate with the discharge chamber through the second gap. 5. The inductively coupled plasma torch according to claim 4, characterized in that the size of the second gap is 1mm˜5mm. 6 . The inductively coupled plasma torch according to claim 1 , wherein the size of the first gap is 1 mm˜10 mm. 7 . The inductively coupled plasma torch according to claim 1 , wherein the inner diameter of the first hollow pipe is 40 mm to 80 mm, and the thickness of the first hollow pipe is 1 mm to 3 mm. 8 . The inductively coupled plasma torch according to claim 1 , wherein the inner diameter of the second hollow pipe is 48 mm to 90 mm, and the thickness of the second hollow pipe is 2 mm to 4 mm. 9. The inductively coupled plasma torch according to any one of claims 1 to 8, characterized in that, both the coolant inlet assembly and the coolant outlet assembly are fixed on the outer wall of the second hollow pipe , and the coolant introduction component is located at the bottom end of the second hollow pipe, and the coolant outlet component is located at the top end of the second hollow pipe. 10. The inductively coupled plasma torch according to any one of claims 1 to 8, characterized in that, the inductively coupled plasma torch further comprises a fixing part and an adjustment ring; The reaction gas introduction pipe is fixed by the fixing member; The top end of the reaction gas introduction pipe is radially provided with a protruding part, the adjustment ring is arranged between the protrusion and the fixing part, and the reaction gas introduction pipe is axially adjusted through the adjustment ring. Position adjustment. 11. A plasma device, characterized by comprising the inductively coupled plasma torch according to any one of claims 1-10.