CN117759951A - A low-voltage sliding arc igniter based on swirling semiconductor - Google Patents

Abstract

A low-voltage sliding arc igniter based on a cyclone semiconductor comprises a jet hole (101), a shell (102), an external gas guide tube (103), mounting threads (104), a cathode (105), an insulator (106), an anode (107), a gas flow channel (108), the semiconductor cyclone (109), a gas inlet hole (110), a positioning step (111) and a gas inlet channel (112). The working process of the igniter is also provided. The invention solves the problem that the existing sliding arc igniter needs high voltage breakdown by utilizing the low voltage arcing characteristic of the semiconductor, thereby solving the problem that the power supply design difficulty is increased due to large impedance change in the working process of the existing sliding arc igniter; the invention also utilizes the characteristics of the semiconductor device, effectively reduces the requirements on power supply design, improves engineering practicability and reduces the volume and weight of a power supply system.

Description

A low-voltage sliding arc igniter based on swirling semiconductor

Technical field

The invention is mainly used in the fields of plasma ignition and combustion, plasma cracking, plasma waste gas treatment and other fields, and specifically relates to a low-pressure sliding arc igniter of a swirling semiconductor.

Background technique

Different from conventional spark discharge, sliding arc discharge is a typical representative of non-thermal arc discharge. Sliding arc discharge can not only release high-temperature plasma, but also produce more active particles. During the working process, there are two working modes: accompanying breakdown mode and stable sliding mode. Sliding arc discharge igniters are widely used in surface treatment of materials, toxic waste removal, ignition and combustion, cracking and other fields. Sliding arc discharge is divided into three stages: the first stage is to break down the air to form a plasma discharge channel; the second stage is to develop into a plasma discharge channel driven by the swirling gas; the third stage is to extinguish the arc. When the arc is extinguished, a new arc will form, repeating itself over and over again, eventually forming a sliding arc.

At present, sliding arc excitation systems usually use air gap discharge, using high voltage to break down the air to form a conductive channel, creating conditions for the formation of sliding arc. Since air is an insulator before breakdown, the entire excitation system exhibits high impedance characteristics. In order to achieve reliable breakdown, the power supply system of the sliding arc must provide a high voltage in the initial stage. However, once the air breaks down, the air gap resistance decreases rapidly, and the entire excitation system presents low impedance characteristics. At this time, the arc voltage drop decreases rapidly. However, in order to ensure the stability of the sliding arc, a large current needs to be provided. Therefore, the sliding arc power supply needs to provide a low voltage and high current at this time.

In summary, due to the large difference in impedance between the breakdown process and the stable discharge process of the current sliding arc igniter, the power supply needs to switch between two working modes, which increases the complexity of the power supply design, resulting in the power supply volume and weight Increase.

Contents of the invention

In view of this, in order to solve the problem of increased difficulty in power supply design due to large impedance changes during the operation of the existing sliding arc igniter, the present invention proposes a low-voltage sliding arc igniter based on a swirling semiconductor, including a jet hole 101, a housing 102, External air duct 103, mounting thread 104, cathode 105, insulator 106, anode 107, air flow channel 108, semiconductor cyclone 109, air inlet hole 110, positioning step 111, air inlet channel 112; wherein

The shell 102 is in the shape of a hollow cylinder as a whole, with an upper end face and a hole in the center of the end face; an internal thread is provided at the lower end of the shell 102, and the internal thread is fixed with the mounting thread 104;

The external air duct 103 is fixedly connected to the casing 102 from the lower part of the casing 102 and close to the upper part of the internal thread of the casing 102. The external air duct 103 does not contact the internal thread of the casing 102. The external air duct 103 is inserted obliquely into the casing 102 from bottom to top; the casing 102 is in A through hole is drilled at the introduction point of the external air bleed pipe 103 to introduce external air through the external air bleed pipe 103;

The cathode 105 is a hollow cylinder with the head and tail open. The outside of the cathode 105 is in the shape of a cylinder. There is a gap between the outer wall of the cathode 105 and the inner wall of the casing 102 along the circumferential direction to form an air inlet channel 112; the inner cavity of the cathode 105 is divided into two parts. There are three sections: the head, the middle, and the tail. The inner cavity of the head of the cathode 105 gradually shrinks toward the head outlet, and the radius gradually decreases; the diameter of the middle part of the inner cavity of the cathode 105 is smaller than the diameter of the tail, and a step is naturally formed in the middle; inside the cathode 105 The tail is processed with a positioning step 111, which is used to clamp the insulator 106. The lower end surface of the positioning step 111 maintains a certain distance from the lower end surface of the cathode 105;

The through hole in the inner cavity of the cathode 105 near the head and the through hole in the head of the housing 102 together form the jet hole 101;

A mounting thread 104 is processed at the tail outside the cathode 105; the mounting thread 104 is located below the air inlet hole 110 and maintains a certain distance from the air inlet hole 110;

Two groups of air inlets 110 are arranged in the middle of the inner cavity of the cathode 105 near the head. Each group of air inlets includes a plurality of air inlets evenly distributed along the circumference. These air inlets are passages penetrating the inner and outer walls of the cathode 105. hole, the air inlet hole 110 is connected with the air inlet channel 112, the air flow channel 108 and the jet hole 101;

The insulator 106 is a hollow structure located between the cathode 105 and the anode 107, and has a rotationally symmetrical structure around the igniter axis; the outer wall of the insulator 106 is divided into three sections of cylindrical structures: upper, middle and lower, and the diameter increases sequentially from top to bottom. ; The outer wall surface of the upper cylinder is kept at a certain distance from the inner wall surface of the cathode 105; the middle cylinder and the upper cylinder are immediately adjacent to each other and protrude outward to form a boss. The boss is located under the two sets of air inlets 110 and is in the middle of the inner cavity of the cathode 105 The wall surface is in an interference fit state; the step formed at the junction of the middle cylinder and the lower cylinder corresponds to the shape of the step formed between the middle and the tail of the cathode 105, so that the lower cylinder is in close contact with the inner wall of the cathode 105; the inside of the insulator 106 The cavity forms two hollow cylinder structures with different diameters. The diameter of the upper hollow cylinder is smaller than that of the lower hollow cylinder structure, and the two together form a through hole; the upper end surface of the insulator 106 maintains a certain distance from the upper end surface of the cathode 105, and the upper end surface of the insulator 106 is lower On the upper end surface of the cathode 105; the lower end surface of the insulator 106 is flush with the upper end surface of the positioning step 111;

The anode 107 is integrated into three parts: a hemispherical discharge end, a thin solid cylinder and a thick solid cylinder; the head is a hemispherical discharge end, protruding upward from the upper end of the insulator 106 and arranged close to the jet hole 101; below the head is Thin solid cylinder, the diameter of the cylinder is equal to the diameter of the head hemisphere; below the thin solid cylinder is a thick solid cylinder, the diameter of the thick solid cylinder is greater than the diameter of the thin solid cylinder; the hemispherical discharge end and thickness of the anode 107 The long solid cylindrical rod is inserted into the large hole in the lower part of the insulator 106 from bottom to top, and passes through the hole into the small hole in the upper part of the insulator 106; there is a gap in the radial direction between the hemispherical discharge end of the head of the anode 107 and the cathode 105; A smooth connection is formed between the outer wall surface of the anode 107 and the outer wall surface of the insulator 106; the air flow channel formed between the anode 107 and the cathode 105, and the air flow channel formed between the insulator 106 and the cathode 105 together constitute the air flow channel 108;

The semiconductor cyclone 109 is composed of a hollow cylinder and a plurality of fan-shaped blades evenly distributed in the radial direction fixed on the outside. The inner diameter of the hollow cylinder is equal to the outer diameter of the thin solid cylinder of the anode 107. The semiconductor cyclone 109 passes through The hollow cylinder is fastened to the outer wall of the anode 107 and is thus embedded between the cathode 105 and the hemispherical head of the anode 107. It is located axially at the upper end of the insulator 106 but does not contact the insulator 106; the semiconductor cyclone 109 is only A small portion of the airflow channel 108 is blocked.

In one embodiment of the present invention, the number of a group of air inlet holes 110 is 3 to 6; the diameter of the air inlet hole 110 is 1 to 5 mm; the distance between the first group of air inlet holes 110 and the end surface of the igniter head is 15 to 6 mm. 40mm; the distance between the second group of air inlet holes 110 and the end face of the igniter head is 30~60mm; the distance between the mounting thread 104 and the air inlet hole 110 is 60~180mm.

In a specific embodiment of the present invention, the number of one group of air inlet holes 110 is 4; the diameter of the air inlet hole 110 is 2mm; the distance between the first group of air inlet holes 110 and the end surface of the igniter head is 20mm; the second group The distance between the air inlet hole 110 and the end face of the igniter head is 35mm; the distance between the mounting thread 104 and the air inlet hole 110 is 80mm.

In another embodiment of the present invention, the distance between the upper end surface of the insulator 106 and the upper end surface of the cathode 105 is 10 to 40 mm, and the outer diameter of the insulator 106 is 5 to 25 mm; the diameter of the hollow cylinder above the insulator 106 is 1 to 7 mm; and the diameter of the hollow cylinder below is 1 to 7 mm. Diameter is 4~15mm.

In another specific embodiment of the present invention, the distance between the upper end surface of the insulator 106 and the upper end surface of the cathode 105 is 25 mm. The insulator 106 is made of aluminum oxide ceramics. The diameter of the hollow cylinder above the insulator 106 is 4 mm. The diameter of the hollow cylinder below is is 9mm.

In another embodiment of the present invention, the diameter of the hemispherical head of the anode 107 is 1 to 8 mm, and the maximum radial length of the long rod at the bottom is 4 to 10 mm; there is a radial gap between the hemispherical discharge end of the anode 107 head and the cathode 105 is 0.5~3mm.

In another specific embodiment of the present invention, the anode 107 is made of nickel alloy, the diameter of the head hemisphere is 4mm, and the maximum radial length of the bottom long rod is 7mm; The clearance in the radial direction is 1.5mm.

In another embodiment of the present invention, the outer diameter of the housing 102 is 20 to 30 mm; the inclination angle of the external air duct 103 is in the range of 15 to 80 degrees; the inner diameter of the external air duct 103 is 5 to 15 mm;

A flange is arranged at the external air bleed pipe 103, and the flange is coaxial with the igniter;

The diameter of the jet hole 101 is 6~12mm;

The distance between the positioning step 111 and the rear end surface inside the cathode 105 is 2-5 mm.

In yet another specific embodiment of the invention,

The outer diameter of the outer shell 102 is 25mm; the inclination angle of the external air duct 103 is 60 degrees; the inner diameter of the external air duct 103 is 6mm;

The central angle of the semiconductor cyclone 109 blocking the air flow channel 108 does not exceed 10°, and the material of the semiconductor cyclone 109 is ceramic with semiconductor characteristics;

The diameter of the jet hole 101 is 8mm;

The distance between the positioning step 111 and the rear end surface inside the cathode 105 is 3 mm.

The working process of the above-mentioned low-voltage sliding arc igniter based on cyclone semiconductor is as follows: the high voltage provided by the power system is connected to the anode 107 of the igniter through a cable, and the ground terminal of the power system and the cathode 105 are grounded; when power is supplied, due to the igniter semiconductor cyclone One end of 109 is in contact with the cathode 105 and the other end is in contact with the anode 108, so the voltage at both ends increases. The semiconductor cyclone 109 is located in the gap between the cathode 105 and the anode 107. With the two ends of the cathode 105 and the anode 107 As the voltage between them increases, due to the low resistance characteristics of the semiconductor, a flashover phenomenon will occur randomly, resulting in an arc starting effect, causing the cathode 105 and anode 107 to start arcing from the flashover point; while arcing, external air is drawn through The external air bleed pipe 103 carries out air bleed, and the bleed air enters the air inlet channel 112 between the casing 102 and the cathode 105 through the external air bleed pipe 103, then enters the air inlet 110, and then enters the air flow channel 108 for ignition to form a sliding arc. Under the action of pneumatics, the sliding arc slides in the jet hole 101, and finally forms a sliding arc excitation output.

The invention introduces a semiconductor arc starting device based on the traditional sliding arc igniter. The low-voltage arc starting characteristics of semiconductors are used to solve the problem that existing sliding arc igniters require high-voltage breakdown. At the same time, before the low-voltage arcing on the surface of the semiconductor device is achieved, the overall performance is on the order of kiloohms. Taking advantage of these unique advantages of semiconductors, low-voltage sliding arc igniters based on swirling current semiconductors can effectively reduce the requirements for power supply design, improve engineering practicality, and reduce the volume and weight of the power supply system.

Description of the drawings

Figure 1 is a schematic diagram of a low-voltage sliding arc igniter based on swirling flow semiconductors of the present invention. Figure 1 (a) shows a perspective view of the igniter. Figure 1 (b) shows a cross-sectional view of the igniter along the axis direction. Figure 1 ( c) shows an enlarged partial view of the igniter head.

Detailed ways

In order to achieve the above purpose, the present invention provides a low-voltage sliding arc igniter based on a swirling semiconductor. Its technical feature is to change the traditional air breakdown between electrodes to a semiconductor-assisted breakdown, so that the igniter is a resistive load before and after breakdown. , which facilitates power supply design.

The present invention will be described in detail below with reference to the accompanying drawings.

1 , the low-pressure sliding arc igniter based on swirl semiconductor of the present invention (hereinafter referred to as “igniter”) consists of a jet hole 101, a shell 102, an external air duct 103, a mounting thread 104, a cathode 105, an insulator 106, an anode 107, an air flow channel 108, a semiconductor cyclone 109, an air inlet hole 110, a positioning step 111, an air inlet channel 112, etc.

The housing 102 is in the shape of a hollow cylinder as a whole, with an upper end surface, and a hole is drilled in the center of the end surface to form a sliding arc. The inner lower end of the housing 102 is provided with internal threads, and the internal threads are matched and fixed with the mounting threads 104 . The size of the shell 102 should be larger than the peripheral size of the overall internal structure, with an outer diameter of 20 to 30 mm, preferably 25 mm.

The external air duct 103 is fixedly connected to the casing 102 from the lower part of the casing 102 and approximately close to the upper part of the internal thread of the casing 102. The external air duct 103 does not contact the internal thread of the casing 102. The external air duct 103 is inserted into the casing 102 obliquely from bottom to top at an angle of inclination. The range is 15 to 80 degrees, preferably 60 degrees. The housing 102 has a through hole at the introduction point of the external air duct 103 to introduce external air through the external air duct 103 . The inner diameter of the external air induction tube 103 is 5 to 15 mm, preferably 6 mm.

The disc near the external air bleed pipe 103 is a flange for docking installation, and the flange is coaxial with the igniter. In order to achieve a stable connection between the external air bleed pipe 103 and the housing 102, a transitional connection part is formed at the connection between the flange and the shell 102. The transitional connection part is a hollow truncated cone without an upper or lower bottom. The conical cone is coaxial with the igniter, and the bottom of the conical cone is The circumference has the same diameter as the outer circumference of the shell 102 and is fixedly connected. The circumferential diameter of the lower bottom of the truncated cone is larger than the circumferential diameter of the bottom of the truncated cone. The lower bottom circumference of the truncated cone is fixedly connected to the flange. For example, the transition connecting portion can be welded to the housing 102 and the flange by welding.

The cathode 105 is a hollow cylinder processed from, for example, a nickel alloy, with the head and tail ends open. The outside of the cathode 105 is in the shape of a cylinder. There is a gap between the outer wall of the cathode 105 and the inner wall of the casing 102 along the circumferential direction for air intake. Channel 112, as shown in Figure 1(c). The inner cavity of the cathode 105 is divided into three sections: the head, the middle, and the tail. The inner cavity of the head of the cathode 105 gradually shrinks toward the head outlet, and the radius gradually decreases; the diameter of the middle part of the inner cavity of the cathode 105 is smaller than the diameter of the tail, and there is a natural gap between the middle and the tail. A step is formed to adapt to the shape of the insulator 106; a positioning step 111 is processed at an appropriate position at the tail end of the cathode 105 to hold the insulator 106. The positioning step 111 is 2-5mm, preferably 3mm, from the tail end surface inside the cathode 105. The lower end surface of the step 111 maintains a certain distance from the lower end surface of the cathode 105 .

The through hole in the inner cavity of the cathode 105 close to the head of the cathode 105 is the jet hole 101, and the diameter of the jet hole 101 is 6 to 12 mm, preferably 8 mm. The jet hole 101 is also a through hole in the head of the housing 102.

A mounting thread 104 such as M15 is processed at a suitable position at the tail outside the cathode 105 for forming a threaded connection with the internal thread of the housing 102 . The mounting thread 104 is located below the air inlet hole 110 and maintains a certain distance from the air inlet hole 110; the distance between the mounting thread 104 and the air inlet hole 110 is about 60 to 180 mm, preferably 80 mm.

Two groups of air inlets 110 are arranged in the middle of the inner cavity of the cathode 105 near the head. Each group of air inlets includes a plurality of air inlets evenly distributed along the circumference. These air inlets are passages penetrating the inner and outer walls of the cathode 105. hole, the air inlet hole 110 communicates with the air inlet channel 112, the air flow channel 108 (described below) and the jet hole 101. The number of a group of air inlet holes 110 is usually 3 to 6, preferably 4. The diameter of the air inlet 110 is 1-5 mm, preferably 2 mm. The air inlet hole 110 is located above the mounting thread 104. The distance between the first group of air inlet holes 110 and the end face of the igniter head is 15 to 40 mm, preferably 20 mm; the distance between the second group of air inlet holes 110 and the end face of the igniter head is 30 mm. ~60mm, preferably 35mm. The air inlet hole 110 is used to provide a gas source for the sliding arc, ensure that the secondary flow of the combustion chamber enters the jet hole 101 through the air inlet hole 110, and drives the arc to slide to form a sliding arc plasma.

The insulator 106 is a hollow structure located between the cathode 105 and the anode 107, and has a rotationally symmetrical structure around the igniter axis. The outer wall of the insulator 106 is divided into three sections of cylindrical structures: upper, middle and lower, with diameters increasing from top to bottom; the outer wall of the upper cylindrical section maintains a certain distance from the inner wall of the cathode 105, and the gap between them is used to generate arcs; the middle section of the cylinder and the upper section The immediate vicinity of the cylinder protrudes outward to form a boss. The boss is located under the two sets of air inlet holes 110 and is in an interference fit state with the inner wall surface of the middle part of the inner cavity of the cathode 105 (it can also be understood that the inner diameter of the cathode 105 is in an interference fit with the outside of the boss). diameters are equal), and a cavity is formed between the outer wall of the insulator 106 and the inner wall of the cathode 105 between the middle cylindrical boss and the lower cylinder. This cavity is not connected to the air inlet 110 (can be understood as In order to reduce the weight of the material); the step formed at the junction of the middle cylinder and the lower cylinder corresponds to the shape of the step formed between the middle and the tail of the cathode 105, so that the lower cylinder is in close contact with the inner wall of the cathode 105. The internal cavity of the insulator 106 forms two hollow cylinder structures with different diameters. The diameter of the upper hollow cylinder is smaller than that of the lower hollow cylinder structure. Together, they form a through hole for installing the anode 107 . The upper end surface of the insulator 106 is kept at a certain distance from the upper end surface of the cathode 105, and the upper end surface of the insulator 106 is lower than the upper end surface of the cathode 105, so as to leave sufficient size for the semiconductor cyclone under the air inlet 110 for the development of the arc; the insulator 106 The distance between the upper end surface and the upper end surface of the cathode 105 is 10 to 40 mm, preferably 25 mm. The lower end surface of the insulator 106 is flush with the upper end surface of the positioning step 111 . The outer diameter of the insulator 106 ranges from 5 to 25 mm. As mentioned above, the outer diameter of the insulator 106 has different sizes from top to bottom. It should be selected according to actual needs. During the selection process, attention should be paid to the coordination with the inner diameter of the cathode 105. The insulator 106 may be made of aluminum oxide ceramic, for example. The diameter of the hollow cylinder above the insulator 106 is 1 to 7 mm, preferably 4 mm; the diameter of the hollow cylinder below is 4 to 15 mm, preferably 9 mm.

The anode 107 is, for example, a metal electrode processed from nickel alloy, and the whole is formed by integrating three parts: a hemispherical discharge end, a thin solid cylinder, and a thick solid cylinder; or as shown in Figure 1 (b), the head is a hemispherical The discharge end is arranged close to the jet hole 101; below the head is a thin solid cylinder, the diameter of which is equal to the diameter of the head hemisphere; below the thin solid cylinder is a thick solid cylinder, and the diameter of the thick solid cylinder is larger than the diameter of the thin solid cylinder body diameter. In practical applications, the other parts of the anode 107 except for the hemispherical head are composed of solid cylindrical long rods. The cross-section is not limited to circular, but is preferably circular, but the cross-section must be a centrally symmetrical figure. In one embodiment of the present invention, the diameter of the head hemisphere is 1 to 8 mm, preferably 4 mm, and the maximum radial length of the bottom cylindrical rod is 4 to 10 mm, preferably 7 mm. The hemispherical discharge end of the anode 107 and the thick solid cylindrical long rod are inserted into the large hole at the lower part of the insulator 106 from bottom to top, and pass through the hole into the small hole at the upper part of the insulator 106. The external wire enters from the outside to the inside and connects with the lower end of the anode 107. connect. It is necessary to ensure that there is a gap in the radial direction between the hemispherical discharge end of the head of the anode 107 and the cathode 105, which is generally 0.5 to 3 mm, preferably 1.5 mm. A smooth connection is formed between the outer wall surface of the anode 107 and the outer wall surface of the insulator 106 . The air flow channel formed between the anode 107 and the cathode 105 and the air flow channel formed between the insulator 106 and the cathode 105 together constitute the air flow channel 108. The air inlet 110 is a cylindrical through hole, and the external air is introduced through the external air pipe 103. The air enters the air inlet channel 112 between the housing 102 and the cathode 105 through the external air pipe 103, and then enters the air inlet 110. Then it enters the air flow channel 108 for ignition to form a sliding arc. Finally, the sliding arc develops from the jet hole 101 to the outside of the igniter.

The semiconductor cyclone 109 is composed of a hollow cylinder and a plurality of fan-shaped blades evenly distributed in the radial direction fixed on the outside. The cyclone 109 is known to those skilled in the art. The present invention uses semiconductor materials to make the cyclone 109. The purpose is to utilize the low-voltage arc starting characteristics of semiconductors to solve the problem that existing sliding arc igniters require high-voltage breakdown. The inner diameter of the hollow cylinder is equal to the outer diameter of the thin solid cylinder of the anode 107. The semiconductor cyclone 109 passes through the hollow cylinder. The body is fastened to the outer wall surface of the anode 107 and is thus embedded between the cathode 105 and the hemispherical head (i.e., the discharge end) of the anode 107. It is located axially at the upper end of the insulator 106 but does not contact the insulator 106. The semiconductor cyclone 109 only blocks a very small part of the airflow channel 108 , and preferably the blocked center angle does not exceed 10°, and the center point refers to the center of the circle formed by the inner wall of the cathode 105 . The material of the semiconductor cyclone 109 can be selected from ceramics with semiconductor characteristics such as zinc oxide and silicon carbide. Its main function is to change the original air gap into a semiconductor connection and change the impedance characteristics at the breakdown moment. Since the semiconductor cyclone 109 shown in FIG. 1 is a cross-sectional view, the shape may seem asymmetrical, but this is a true representation.

The working process of the igniter is as follows: the high voltage provided by the power system is connected to the anode 107 of the igniter through a cable, and the ground terminal of the power system and the cathode 105 are grounded. When power is supplied, since one end of the igniter semiconductor cyclone 109 is in contact with the cathode 105 and the other end is in contact with the anode 107, the voltage at both ends increases, and the semiconductor cyclone 109 is located in the gap between the cathode 105 and the anode 107. , a flashover phenomenon will occur randomly during ignition, resulting in arc ignition, causing the cathode 105 and anode 107 to start arcing from the flashover point. At the same time as the arc is struck, the external air is introduced through the external air pipe 103. The air enters the air inlet channel 112 between the housing 102 and the cathode 105 through the external air pipe 103, then enters the air inlet hole 110, and then enters the air flow channel 108. , used for ignition to form a sliding arc. Under the action of pneumatics, the sliding arc slides in the jet hole 101, and finally forms a sliding arc excitation output.

In order to solve the problem of difficulty in power supply design caused by large impedance changes during the operation of the existing sliding arc igniter, the present invention proposes a low-voltage sliding arc igniter of a swirling semiconductor. This igniter introduces a semiconductor arc starting device based on the traditional sliding arc igniter, and utilizes the low-voltage arc starting characteristics of the semiconductor to solve the problem that the existing sliding arc igniter requires high-voltage breakdown. With the unique advantages of semiconductor devices, the requirements for power supply design are reduced, engineering practicality is improved, and the volume and weight of the power supply system are reduced.

Claims (10)

1. The low-voltage sliding arc igniter based on the cyclone semiconductor is characterized by comprising a jet hole (101), a shell (102), an external gas guide pipe (103), mounting threads (104), a cathode (105), an insulator (106), an anode (107), a gas flow channel (108), a semiconductor cyclone (109), a gas inlet hole (110), a positioning step (111) and a gas inlet channel (112); wherein the method comprises the steps of

The shell (102) is integrally hollow and cylindrical, and is provided with an upper end face, and a hole is punched in the center of the end face; an internal thread is arranged at the lower end of the interior of the shell (102), and the internal thread is matched and fixed with the mounting thread (104);

the external air guide pipe (103) is fixedly connected with the shell (102) from the lower part of the shell (102) and the position close to the upper part of the internal thread of the shell (102), the external air guide pipe (103) is not contacted with the internal thread of the shell (102), and the external air guide pipe (103) is obliquely inserted into the shell (102) from bottom to top; the shell (102) is provided with a through hole at the introduction position of the external gas-guiding pipe (103) for introducing external gas through the external gas-guiding pipe (103);

the cathode (105) is a hollow cylinder, the two ends of the head and the tail are open, the outside of the cathode (105) is in a cylinder shape, and a gap is reserved between the outer wall surface of the cathode (105) and the inner wall surface of the shell (102) along the circumferential direction to form an air inlet channel (112); the inner cavity of the cathode (105) is divided into a head section, a middle section and a tail section, the inner cavity of the head of the cathode (105) is gradually folded towards the outlet of the head, and the radius is gradually reduced; the diameter of the middle part of the inner cavity of the cathode (105) is smaller than the diameter of the tail part, and a step is naturally formed in the middle; a positioning step (111) is processed at the tail part inside the cathode (105) and is used for clamping the insulator (106), and the lower end surface of the positioning step (111) is kept at a certain distance from the lower end surface of the cathode (105);

the through hole of the inner cavity of the cathode (105) close to the head part and the through hole of the head part of the shell (102) form a jet hole (101) together;

machining a mounting thread (104) on the tail part outside the cathode (105); the mounting screw thread (104) is positioned below the air inlet hole (110) and keeps a certain distance from the air inlet hole (110);

an upper air inlet hole and a lower air inlet hole (110) are arranged in the middle of the inner cavity of the cathode (105) near the head, each air inlet hole comprises a plurality of air inlet holes which are uniformly distributed along the circumference, the air inlet holes are through holes penetrating through the inner wall surface and the outer wall surface of the cathode (105), and the air inlet holes (110) are communicated with an air inlet channel (112), an air flow channel (108) and jet holes (101);

the insulator (106) is a hollow structure body positioned between the cathode (105) and the anode (107) and has a rotationally symmetrical structure around the axis of the igniter; the outer wall of the insulator (106) is divided into an upper section, a middle section and a lower section of cylinder structure, and the diameters of the cylinder structures are sequentially increased from top to bottom; the outer wall surface of the upper section cylinder is kept at a certain distance from the inner wall surface of the cathode (105); the adjacent parts of the middle section cylinder and the upper section cylinder are outwards protruded to form a boss, and the boss is positioned below the two groups of air inlets (110) and is in interference fit with the inner wall surface of the middle part of the inner cavity of the cathode (105); the step formed at the junction of the middle section cylinder and the lower section cylinder is just corresponding to the step formed between the middle part and the tail part of the cathode (105), so that the lower section cylinder is tightly contacted with the inner wall of the cathode (105); the inner cavity of the insulator (106) forms two hollow cylinder structures with different diameters, the diameter of the upper hollow cylinder is smaller than that of the lower hollow cylinder structure, and the upper hollow cylinder and the lower hollow cylinder form a through hole together; the upper end face of the insulator (106) is kept at a certain distance from the upper end face of the cathode (105), and the upper end face of the insulator (106) is lower than the upper end face of the cathode (105); the lower end surface of the insulator (106) is flush with the upper end surface of the positioning step (111);

the anode (107) is formed by integrating a hemispherical discharge end, a thin solid cylinder and a thick solid cylinder; the head part is a hemispherical discharge end, protrudes upwards from the upper end surface of the insulator (106) and is arranged close to the jet hole (101); below the head is a thin solid cylinder with the diameter equal to the diameter of the hemispherical head; a thick solid cylinder is arranged below the thin solid cylinder, and the diameter of the thick solid cylinder is larger than that of the thin solid cylinder; the hemispherical discharge end of the anode (107) and the thick and thin solid cylinder long rod are inserted into the large hole at the lower part of the insulator (106) from bottom to top, and pass through the hole to enter the small hole at the upper part of the insulator (106); a gap is reserved between the head hemispherical discharge end of the anode (107) and the cathode (105) in the radial direction; the outer wall surface of the anode (107) and the outer wall surface of the insulator (106) are connected in a smooth manner; the gas flow channel formed between the anode (107) and the cathode (105), and the gas flow channel formed between the insulator (106) and the cathode (105) together form a gas flow channel (108);

the semiconductor cyclone (109) is composed of a hollow cylinder and a plurality of fan-shaped blades which are fixed outside the hollow cylinder and uniformly distributed along the radial direction, the inner diameter of the hollow cylinder is equal to the outer diameter of the thin solid cylinder of the anode (107), the semiconductor cyclone (109) is fixedly arranged on the outer wall surface of the anode (107) through the hollow cylinder, and is embedded between the cathode (105) and the hemispherical head of the anode (107), and the semiconductor cyclone is axially positioned at the upper end position of the insulator (106) but is not contacted with the insulator (106); the semiconductor cyclone (109) shields only a small part of the airflow channel (108).

2. The low voltage sliding arc igniter based on a cyclone semiconductor of claim 1 wherein the number of a set of air inlet holes (110) is 3-6; the diameter of the air inlet hole (110) is 1-5 mm; the distance between the first group of air inlets (110) and the end face of the head of the igniter is 15-40 mm; the distance between the second group of air inlets (110) and the end face of the head of the igniter is 30-60 mm; the distance between the mounting screw thread (104) and the air inlet hole (110) is 60-180 mm.

3. The low voltage, sliding arc igniter based on a swirl semiconductor of claim 2 wherein the number of air inlet holes (110) in a set is 4; the diameter of the air inlet hole (110) is 2mm; the distance between the first group of air inlet holes (110) and the end face of the head part of the igniter is 20mm; the distance between the second group of air inlet holes (110) and the end face of the head of the igniter is 35mm; the distance between the mounting screw thread (104) and the air inlet hole (110) is 80mm.

4. The low-voltage sliding arc igniter based on the cyclone semiconductor according to claim 1, wherein the upper end surface of the insulator (106) is 10-40 mm away from the upper end surface of the cathode (105), and the outer diameter of the insulator (106) is 5-25 mm; the diameter of the hollow cylinder above the insulator (106) is 1-7 mm; the diameter of the hollow cylinder at the lower part is 4-15 mm.

5. The low-voltage sliding arc igniter based on cyclone semiconductor as claimed in claim 4, wherein the upper end surface of the insulator (106) is 25mm from the upper end surface of the cathode (105), and the insulator (106) is made of aluminum oxide ceramic; the diameter of the hollow cylinder above the insulator (106) is 4mm; the diameter of the lower hollow cylinder is 9mm.

6. The low voltage sliding arc igniter based on the cyclone semiconductor according to claim 1, wherein the diameter of the hemispherical head of the anode (107) is 1-8 mm, and the maximum radial length of the bottom long rod is 4-10 mm; the gap between the head hemispherical discharge end of the anode (107) and the cathode (105) in the radial direction is 0.5-3 mm.

7. A low voltage sliding arc igniter based on a swirl semiconductor according to claim 6 wherein the anode (107) is machined from nickel alloy with a head hemisphere diameter of 4mm and a bottom long bar maximum radial length of 7mm; the gap between the head hemispherical discharge end of the anode (107) and the cathode (105) in the radial direction is 1.5mm.

8. A low voltage sliding arc igniter based on a swirl semiconductor as defined in claim 1,

the outer diameter of the shell (102) is 20-30 mm; the inclination angle range of the external air suction pipe (103) is 15-80 degrees; the inner diameter of the external air guide pipe (103) is 5-15 mm;

a flange is arranged at the external gas-introducing pipe (103), and the flange is coaxial with the igniter;

the diameter of the jet hole (101) is 6-12 mm;

the tail end face of the positioning step (111) from the inside of the cathode (105) is 2-5mm.

9. The low voltage, spiral-flow semiconductor-based sliding arc igniter of claim 8,

the outer diameter of the shell (102) is 25mm; the inclination angle of the external air suction pipe (103) is 60 degrees; the inner diameter of the external air guide pipe (103) is 6mm;

the center angle of the gas flow channel (108) is not more than 10 degrees, and the semiconductor cyclone (109) is made of ceramics with semiconductor characteristics;

the diameter of the jet hole (101) is 8mm;

the positioning step (111) is 3mm away from the tail end face inside the cathode (105).

10. The low voltage, swirl semiconductor-based sliding arc igniter of any one of claims 1 to 9 wherein the igniter operates as follows: the high voltage provided by the power supply system is connected with an anode (107) of the igniter through a cable, and the grounding end of the power supply system and the cathode (105) are grounded; when the power is on, one end of the igniter semiconductor cyclone (109) is contacted with the cathode (105), and the other end of the igniter semiconductor cyclone is contacted with the anode (107), so that the voltage at two ends of the igniter semiconductor cyclone is increased, the semiconductor cyclone (109) is positioned at a gap position between the cathode (105) and the anode (107), and as the voltage between the two ends of the cathode (105) and the anode (107) is increased, a flashover phenomenon randomly occurs due to the low resistance characteristic of a semiconductor, so that an arc striking effect is generated, and the cathode (105) and the anode (107) start to strike an arc from the flashover position; at the same time of arcing, external air bleed is carried out through an external air bleed pipe (103), the air bleed enters an air inlet channel (112) between the shell (102) and the cathode (105) through the external air bleed pipe (103), then enters an air inlet hole (110) and then enters an air flow channel (108) for ignition, a sliding arc is formed, the sliding arc slides in the jet hole (101) under the pneumatic action, and finally, a sliding arc excitation output is formed.