Plasma cutting forming device for preparing motorcycle frame

Abstract

The invention discloses a plasma cutting forming device for preparing a motorcycle frame, and relates to the technical field of plasma cutting, the plasma cutting forming device comprises a gun head and a handle, an air supply structure is jointly installed between the gun head and the handle, a nozzle is installed on the gun head in a threaded mode and communicated with the gun head, and the air supply structure injects air into the nozzle to form plasma flames. The device has the advantages that automatic dynamic synchronization of the cutting speed and the air inflow is achieved through the speed synchronizing mechanism, different cutting working conditions are accurately adapted, the problems of notch burning loss, slag adhering or incomplete cutting caused by mismatching of the cutting speed and the air inflow are solved, and the machining precision of the frame component is remarkably improved. In the aspect of height adaptation, manual rough adjustment and automatic self-adaptive fine adjustment are combined, the machining requirements of frame components with different thicknesses can be met, the surface flatness difference of workpieces can be coped with, operation is easy and convenient, and the manual adjustment difficulty is reduced.

Description

Technical Field

[0001] This invention relates to the field of plasma cutting technology, and in particular to a plasma cutting and forming apparatus for manufacturing motorcycle frames. Background Technology

[0002] In the manufacturing process of motorcycle frames, plasma cutting is widely used due to its advantages such as fast cutting speed, small heat-affected zone, and smooth cut. However, existing cutting devices have many shortcomings: First, the cutting speed and the air intake of the gas supply structure cannot be adjusted synchronously. When the operator changes the cutting speed, if the air intake is not adapted in time, it will lead to unstable plasma flame intensity, resulting in problems such as cut burn, slag buildup, or incomplete cutting, which will affect the processing accuracy of the frame components. Second, the distance between the cutting device and the workpiece surface is inconvenient to adjust. Motorcycle frame components are mostly irregular structures with different processing heights in different areas. Existing devices lack a flexible height adaptation mechanism, which can easily exacerbate nozzle wear or reduce cutting quality due to improper distance.

[0003] To solve the above-mentioned technical problems, the present invention proposes a plasma cutting and forming device for motorcycle frame manufacturing. Summary of the Invention

[0004] The purpose of this invention is to solve the problems in the background art, and to propose a plasma cutting and forming apparatus for manufacturing motorcycle frames.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A plasma cutting and forming apparatus for manufacturing motorcycle frames includes a gun head and a handle. An air supply structure is installed between the gun head and the handle. A nozzle is threadedly installed and connected to the gun head. The air supply structure forms a plasma flame by injecting air into the nozzle. Two sets of speed synchronization mechanisms are symmetrically arranged on the gun head. One of the speed synchronization mechanisms adjusts the air intake of the air supply structure according to the cutting speed to synchronize the cutting movement speed.

[0006] In the aforementioned plasma cutting and forming apparatus for preparing a motorcycle frame, the handle is provided with an air guide groove one and an air guide groove two.

[0007] In the above-mentioned plasma cutting and forming device for preparing motorcycle frames, the air supply structure includes an air pipe one and an air pipe two fixedly connected between the gun head and the handle. The air pipe one is connected to the air guide groove one, and the air pipe two is connected to the air guide groove two. A venturi groove is opened in the air pipe two.

[0008] In the aforementioned plasma cutting and forming apparatus for preparing a motorcycle frame, a gear three, a gear two, and a gear one are rotatably arranged on one side of the handle, and the gear two meshes with the gear three and the gear one. A knob two is fixedly arranged on one side of the gear three, and a knob one is fixedly arranged on one side of the gear one.

[0009] In the aforementioned plasma cutting and forming device for manufacturing motorcycle frames, threaded grooves are provided between knob two and gear three, and between knob one and gear one. A push rod one is threadedly installed in the threaded groove between knob two and gear three, and a push rod two is threadedly installed in the threaded groove between knob one and gear one. A limit block is fixedly provided on one side of each of the push rod one and push rod two, and with the limit block provided, push rod one and push rod two are slidably disposed in the handle.

[0010] In the aforementioned plasma cutting and forming apparatus for manufacturing motorcycle frames, a toothed rod is slidably provided on one side of the handle, and the toothed rod meshes with a gear three. A torsion spring is provided between the gear three and the handle.

[0011] In the aforementioned plasma cutting and forming apparatus for manufacturing motorcycle frames, the speed synchronization mechanism includes a sleeve fixedly mounted on the gun head, a threaded rod rotatably mounted inside the sleeve, a torsion ring fixedly mounted on the threaded rod, a sliding sleeve threadedly mounted on the lower end of the threaded rod, two guide rods fixedly mounted on the sliding sleeve, both guide rods slidably mounted inside the sleeve, and a height adjustment component is provided inside the sliding sleeve.

[0012] In the plasma cutting and forming apparatus for manufacturing a motorcycle frame described above, the height adjustment component includes a circular plate fixedly disposed within a sliding sleeve. A second spring is fixedly disposed on the lower surface of the circular plate. A vertical rod is fixedly disposed at the lower end of the second spring. A rotating shaft is rotatably disposed at the lower end of the vertical rod. A movable wheel is fixedly disposed on the rotating shaft.

[0013] In the aforementioned plasma cutting and forming apparatus for manufacturing motorcycle frames, two rotating rods are provided on one side of the gun head. A transmission mechanism is provided between one of the rotating shafts and the two rotating rods. A shield is fixedly provided on one side of the gun head, and the shield shields the transmission mechanism. A positioning plate is fixedly provided on one side of the gun head, and a spring is fixedly provided on one side of the positioning plate. A sliding groove is opened on one side of the gun head, and one of the rotating rods is slidably disposed in the sliding groove. One end of the spring is fixedly connected to the rotating rod. A tapered rod is fixedly provided on one end of the other rotating rod. Multiple sliders are slidably disposed on the tapered rod. Each of the multiple sliders is hinged with a push rod, and the multiple push rods are connected to a gear rack.

[0014] In the above-mentioned plasma cutting and forming device for preparing a motorcycle frame, a plasma generator is fixedly installed inside the gun head. The plasma generator has a central hole and multiple side holes 32 are provided on the plasma generator. The multiple side holes 32 are equidistant from the central hole 31.

[0015] Compared with existing technologies, the advantages of this invention are as follows: This device achieves automatic dynamic synchronization of cutting speed and air intake through a speed synchronization mechanism, accurately adapting to different cutting conditions and avoiding problems such as cut burns, slag buildup, or incomplete cutting caused by mismatch between the two, significantly improving the processing accuracy of vehicle frame components. In terms of high adaptability, it combines manual coarse adjustment with automatic adaptive fine adjustment, meeting the processing needs of vehicle frame components of different thicknesses and addressing differences in workpiece surface flatness. Operation is simple and convenient, reducing the difficulty of manual adjustment. Regarding airflow supply, the dual-channel air supply design with venturi grooves not only increases gas flow rate but also enhances supply stability, making the intensity and shape of the plasma flame more stable, thereby improving overall cutting efficiency. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of a plasma cutting and forming device for manufacturing motorcycle frames proposed in this invention; Figure 2 This is a structural schematic diagram from another perspective of the present invention; Figure 3 Here are structural diagrams of push rod one and push rod two; Figure 4 for Figure 3 Enlarged structural diagram of part a; Figure 5 This is a top view of the present invention; Figure 6 for Figure 5 A cross-sectional view of the structure along the AA direction.

[0017] In the diagram: 1. Gun head; 2. Nozzle; 3. Air tube one; 4. Air tube two; 5. Gear rack; 6. Trigger; 7. Handle; 8. Knob one; 9. Knob two; 10. Shield; 11. Rotating shaft; 12. Moving wheel; 13. Vertical rod; 14. Slide groove; 15. Push rod one; 16. Push rod two; 17. Gear one; 18. Gear two; 19. Torsion spring; 20. Gear three; 21. Transmission mechanism; 22. Sliding sleeve; 23. Guide rod; 24. Threaded rod; 25. Rotating rod; 26. Slider; 27. Conical rod; 28. Spring one; 29. ​​Air guide groove one; 30. Venturi groove; 31. Center hole; 32. Side hole. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Reference Figure 1 , Figure 2 as well as Figure 6 A plasma cutting and forming device for motorcycle frame manufacturing includes a gun head 1 and a handle 7. An air supply structure is installed between the gun head 1 and the handle 7. A nozzle 2 is threaded onto and connected to the gun head 1. The nozzle 2 is made of copper alloy, possessing good thermal conductivity and corrosion resistance. Its upper end is connected to the lower end of the gun head 1 via an external thread. This threaded connection allows for quick replacement of nozzles 2 with different orifice diameters according to cutting requirements (such as material thickness and cutting precision), improving the device's versatility. The outlet end of the nozzle 2 adopts a tapered surface structure, which can further compress the plasma gas flow, enhancing the flame's impact intensity and focusing effect.

[0020] The gas supply structure forms a plasma flame by injecting gas into the nozzle 2. The gas supply structure includes a gas pipe 3 and a gas pipe 4 fixedly connected between the nozzle 1 and the handle 7. The handle 7 has a gas guide groove 29 and a gas guide groove 2. Gas pipe 3 is connected to gas guide groove 29, and gas pipe 4 is connected to gas guide groove 2. A Venturi groove 30 is formed inside gas pipe 4. The gas supply structure provides a stable working gas (such as argon, nitrogen, or an argon-nitrogen mixture) for plasma cutting. It adopts a dual-path parallel design, including gas pipe 3, gas pipe 4, and gas guide grooves 29 and 2. The handle 7 has independent gas guide grooves 29 and 2 along the axial direction, serving as the introduction channels for the two gas paths. Both gas pipes 3 and 4 are made of high-pressure corrosion-resistant hoses, with both ends fixedly connected to the air inlet of the nozzle 1 and the gas guide groove outlet of the handle 7 by welding, forming a sealed gas delivery channel.

[0021] The Venturi groove 30 adopts a contraction-to-expansion structure. According to the Venturi effect, when the gas flows through the contraction section, the flow velocity will increase significantly, thereby enhancing the kinetic energy of the gas. This allows the gas to more efficiently cooperate with the plasma generator after entering the nozzle 1, forming a high-intensity, high-stability plasma flame. Simultaneously, the cooperation between the dual gas pipes and the gas guide groove allows for the adjustment of the opening of the two channels by moving push rod 15 and push rod 16 respectively, achieving graded adjustment of the air intake to adapt to the needs of different cutting scenarios.

[0022] The handle 7 is made of a composite of engineering plastic and non-slip rubber, conforming to ergonomic design. The grip area features non-slip textures to reduce fatigue during prolonged operation. A trigger 6 is hinged to the lower grip area of ​​the handle 7, facilitating thumb operation. Its design balances start / stop control and safety: a limit switch is located inside the trigger 6, electrically connected to the plasma generator's control circuit via a wire, and also linked to the solenoid valve of the external gas source. When the trigger 6 is pressed, the limit switch closes, activating the plasma generator for ionization and simultaneously opening the gas source solenoid valve to allow working gas to enter the supply channel. When the trigger 6 is released, the limit switch automatically disconnects, the plasma generator stops operating, and the gas source solenoid valve closes, achieving "one-button start / stop" linkage control, improving operational continuity and safety. Furthermore, a return spring is located at the hinge of the trigger 6, ensuring automatic rebound after pressing. The spring force is adjustable to accommodate different operator habits.

[0023] A plasma generator is fixedly installed inside the nozzle 1. The nozzle 1 is the core working module of the device, integrally molded from a high-temperature resistant alloy material, with a pre-reserved installation chamber inside, in which the plasma generator is fixedly embedded. The plasma generator uses a ceramic insulating shell, with a central hole 31 opened in the central axis, serving as the main output channel for the plasma flame and ensuring the concentrated penetration of the flame. Around the central hole 31, multiple side holes 32 are distributed in a ring at equal angles. The side holes 32 and the central hole 31 form an internal and external airflow coordination structure, which can both guide and constrain the central flame to prevent flame dispersion, and quickly remove high-temperature waste and heat from the cutting area, reducing the heat-affected zone and improving the smoothness of the cut.

[0024] Reference Figures 3-6One side of the handle 7 is equipped with a rotatable gear 3 20, a gear 2 18, and a gear 1 17, with gear 2 18 meshing with gear 3 20 and gear 1 17. A knob 2 9 is fixedly mounted on one side of gear 3 20, and a knob 1 8 is fixedly mounted on one side of gear 1 17. Both knobs 1 8 and 2 9 have anti-slip teeth on their outer surfaces for easy manual adjustment. A through internal thread groove is formed at the center of knob 1 8 and gear 1 17. The outer surface of push rod 1 15 has an external thread that matches the thread groove. The knob 2 (9) and gear 3 (20) are threaded together. Similarly, a through-threaded groove is provided at the center of knob 2 (9) and gear 3 (20). Push rod 2 (16) is threadedly connected to this groove. Push rod 2 (16) is threadedly installed in the groove between knob 1 (8) and gear 1 (17). Limit blocks are fixedly installed on one side of push rod 1 (15) and push rod 2 (16). With the limit blocks, push rod 1 (15) and push rod 2 (16) are slidably positioned within handle 7, forming a sliding guide constraint. This ensures that push rod 1 (15) and push rod 2 (16) can only move axially and cannot rotate synchronously with the gears. A rack 5 is slidably mounted on one side of handle 7, meshing with gear 3 (20). A torsion spring 19 is provided between gear 3 (20) and handle 7. When knob 1 (8) or knob 2 (9) is rotated, the threaded transmission converts the movement of the push rod into axial movement, thereby adjusting the opening of air guide groove 1 (29) or air guide groove 2 (2), achieving manual fine-tuning of the air intake volume to meet the needs of special cutting scenarios.

[0025] The handle 7 has a rack and pinion groove on its outer side. In the initial state, the torsion spring 19 is in a naturally extended state. When the rack 5 slides along the rack and pinion groove, it drives the gear 3 20 to rotate, and the torsion spring 19 undergoes elastic deformation to store energy. When the rack 5 loses driving force, the torsion spring 19 releases its elastic force, drives the gear 3 20 to rotate in the opposite direction, and then drives the rack 5 and the gear transmission assembly to reset, ensuring the cycle stability of automatic adjustment.

[0026] Two sets of speed synchronization mechanisms are symmetrically arranged on the gun head 1. One set of speed synchronization mechanisms adjusts the air intake of the air supply structure according to the cutting speed to synchronize the cutting speed. The speed synchronization mechanism includes a sleeve fixedly mounted on the gun head 1, with a threaded rod 24 rotatably mounted inside the sleeve. The sleeve is made of stainless steel and is vertically welded to the side wall of the gun head 1. The inside is a smooth hollow structure. A torsion ring is fixedly mounted on the threaded rod 24. A sliding sleeve 22 is threadedly installed at the lower end of the threaded rod 24. Two guide rods 23 are fixedly mounted on the sliding sleeve 22. Both guide rods 23 are slidably mounted inside the sleeve. A height adjustment component is provided inside the sliding sleeve 22. The height adjustment component includes a circular plate fixedly mounted inside the sliding sleeve 22. A spring 2 is fixedly mounted on the lower surface of the circular plate. A vertical rod 13 is fixedly mounted at the lower end of the spring 2. A rotating shaft 11 is rotatably mounted at the lower end of the vertical rod 13. A moving wheel 12 is fixedly mounted on the rotating shaft 11.

[0027] Two rotating rods 25 are provided on one side of the gun head 1. A transmission mechanism 21 is provided between one rotating shaft 11 and the two rotating rods 25. A shield 10 is fixedly provided on one side of the gun head 1, and the shield 10 shields the transmission mechanism 21. A positioning plate is fixedly provided on one side of the gun head 1. A spring 28 is fixedly provided on one side of the positioning plate. A sliding groove 14 is opened on one side of the gun head 1. One of the rotating rods 25 is slidably disposed in the sliding groove 14. One end of the spring 28 is fixedly connected to the rotating rod 25. The other rotating rod 25 is rotatably disposed on one side of the gun head 1. A tapered rod 27 is fixedly provided at one end of the rotating rod 25. Multiple guide grooves are opened on the surface of the tapered rod 27 along the generatrix direction. A slider 26 is slidably disposed in each guide groove. A push rod is hinged on each slider 26. Multiple push rods are slidably connected to the toothed rod 5. The transmission mechanism 21 includes pulleys that are fixedly mounted on one end of two rotating rods 25 and one end of rotating shaft 11, and a conveyor belt is sleeved on the multiple pulleys that rotate together.

[0028] When the cutting speed increases, the rotational speed of the moving wheel 12 increases, which drives the rotational speed of the rotating rod 25 and the conical rod 27 to increase synchronously through the transmission mechanism 21. Under the action of centrifugal force, the slider 26 slides outward along the guide groove of the conical rod 27, pushing the push rod to drive the rack 5 to move along the rack groove. The rack 5 drives the gear 3 20 to rotate, which in turn drives the gear 1 17 to rotate through the gear 2 18, thereby driving the push rod 1 15 and the push rod 2 16 to move synchronously, increasing the opening of the air guide groove 1 29 and the air guide groove 2, increasing the air intake, and making the flame intensity match the cutting speed. When the cutting speed decreases, the centrifugal force of the slider 26 decreases. Under the reset action of the spring 1 28 and the torsion spring 19, each transmission component moves in the opposite direction, and the air intake automatically decreases, realizing dynamic synchronous adjustment.

[0029] To further clarify, the aforementioned fixed connection should be interpreted broadly unless otherwise explicitly specified and limited. For example, it may be welding, gluing, or integral molding, or other conventional methods well known to those skilled in the art.

[0030] The specific operation steps of this invention are as follows: Pre-treatment and adjustment: Select a nozzle 2 with an appropriate orifice diameter according to the material and thickness of the motorcycle frame component to be cut, and install it on the gun head 1 by screwing it on; connect the device to the external air source and power source, and check the sealing of each component connection and the flexibility of operation; the operator holds the handle 7, places the device on the surface of the workpiece, rotates the torsion ring at the upper end of the threaded rod 24, adjusts the height of the sliding sleeve 22, so that the moving wheel 12 contacts the surface of the workpiece, and the spring 2 is in a slightly compressed state, thus completing the manual coarse adjustment of the cutting distance.

[0031] Start-up and gas supply: When the operator presses trigger 6, the limit switch closes, the plasma generator starts, the gas source solenoid valve opens, and the working gas enters gas pipe 3 and gas pipe 4 through gas guide channel 1 29 and gas guide channel 2 respectively; the venturi groove 30 in gas pipe 4 accelerates the gas flow rate, and the two gas streams converge in the nozzle 1 and flow through the plasma generator, forming a stable plasma flame under ionization, which is then ejected through nozzle 2.

[0032] Cutting and Synchronization Adjustment: The device moves along the preset cutting path, and the moving wheel 12 rolls, driving the transmission mechanism 21 to rotate, which in turn drives the rotating rod 25 and the conical rod 27 to rotate. The faster the cutting speed, the greater the centrifugal force of the slider 26, and the farther the toothed rod 5 moves. The gear transmission assembly drives the push rod 15 and push rod 26 to open the air guide groove, increasing the air intake and improving the flame intensity. When the cutting speed slows down, each component moves in the opposite direction under the action of the return spring, reducing the air intake and ensuring stable cut quality. If manual fine-tuning of the air intake is required, the knob 18 or knob 29 can be rotated to adjust the position of the push rod through the threaded transmission to adapt to special cutting conditions.

[0033] Operation completed: After cutting, release trigger 6, the limit switch will be turned off, and the plasma generator and gas source will be shut off simultaneously; clean the waste residue on the surface of the device, check the condition of vulnerable parts such as nozzle 2 and transmission components, and perform maintenance if necessary. Then store the device in a dry and ventilated place.

[0034] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A plasma cutting and forming apparatus for manufacturing motorcycle frames, comprising a gun head (1) and a handle (7), characterized in that, A gas supply structure is installed between the gun head (1) and the handle (7). A nozzle (2) is threaded onto the gun head (1) and connected to it. The gas supply structure forms a plasma flame by injecting gas into the nozzle (2). Two sets of speed synchronization mechanisms are symmetrically arranged on the gun head (1). One set of the speed synchronization mechanisms adjusts the air intake of the air supply structure according to the cutting speed to synchronize the cutting speed.

2. The plasma cutting and forming apparatus for manufacturing motorcycle frames according to claim 1, characterized in that, The handle (7) is provided with an air guide groove 1 (29) and an air guide groove 2.

3. The plasma cutting and forming apparatus for manufacturing motorcycle frames according to claim 1, characterized in that, The air supply structure includes an air pipe 1 (3) and an air pipe 2 (4) fixedly connected between the gun head (1) and the handle (7). The air pipe 1 (3) is connected to the air guide groove 1 (29), and the air pipe 2 (4) is connected to the air guide groove 2. A venturi groove (30) is opened in the air pipe 2 (4).

4. The plasma cutting and forming apparatus for manufacturing motorcycle frames according to claim 1, characterized in that, The handle (7) is rotatably provided with gear three (20), gear two (18) and gear one (17), and gear two (18) meshes with gear three (20) and gear one (17). A knob two (9) is fixedly provided on one side of gear three (20), and a knob one (8) is fixedly provided on one side of gear one (17).

5. The plasma cutting and forming apparatus for manufacturing motorcycle frames according to claim 4, characterized in that, A threaded groove is provided between the second knob (9) and the third gear (20), and between the first knob (8) and the first gear (17). A push rod (15) is threadedly installed in the threaded groove between the second knob (9) and the third gear (20), and a push rod (26) is threadedly installed in the threaded groove between the first knob (8) and the first gear (17). A limit block is fixedly provided on one side of both the first push rod (15) and the second push rod (16), and with the limit block provided, the first push rod (15) and the second push rod (16) are slidably disposed in the handle (7).

6. The plasma cutting and forming apparatus for manufacturing motorcycle frames according to claim 5, characterized in that, A toothed rod (5) is slidably provided on one side of the handle (7), and the toothed rod (5) meshes with the gear three (20). A torsion spring (19) is provided between the gear three (20) and the handle (7).

7. The plasma cutting and forming apparatus for manufacturing motorcycle frames according to claim 6, characterized in that, The speed synchronization mechanism includes a sleeve fixedly mounted on the gun head (1), a threaded rod (24) rotatably mounted inside the sleeve, a torsion ring fixedly mounted on the threaded rod (24), a sliding sleeve (22) threadedly mounted on the lower end of the threaded rod (24), two guide rods (23) fixedly mounted on the sliding sleeve (22), both guide rods (23) slidably mounted inside the sleeve, and a height adjustment component is provided inside the sliding sleeve (22).

8. The plasma cutting and forming apparatus for manufacturing motorcycle frames according to claim 7, characterized in that, The height adjustment component includes a circular plate fixedly installed inside the sliding sleeve (22), a second spring fixedly installed on the lower surface of the circular plate, a vertical rod (13) fixedly installed at the lower end of the second spring, a rotating shaft (11) rotatably installed at the lower end of the vertical rod (13), and a moving wheel (12) fixedly installed on the rotating shaft (11).

9. The plasma cutting and forming apparatus for manufacturing motorcycle frames according to claim 8, characterized in that, Two rotating rods (25) are provided on one side of the gun head (1). A transmission mechanism (21) is provided between one of the rotating shafts (11) and the two rotating rods (25). A shield (10) is fixedly provided on one side of the gun head (1), and the shield (10) shields the transmission mechanism (21). A positioning plate is fixedly provided on one side of the gun head (1). A spring (28) is fixedly provided on one side of the positioning plate. A sliding groove (14) is provided on one side of the gun head (1). One of the rotating rods (25) is slidably provided in the sliding groove (14). One end of the spring (28) is fixedly connected to the rotating rod (25). A tapered rod (27) is fixedly provided on one end of the other rotating rod (25). Multiple sliders (26) are slidably provided on the tapered rod (27). Each slider (26) is hinged with a push rod. Each push rod is connected to a toothed rod (5).

10. The plasma cutting and forming apparatus for manufacturing motorcycle frames according to claim 1, characterized in that, A plasma generator is fixedly installed inside the gun head (1). A central hole (31) is opened in the center of the plasma generator. Multiple side holes (32) are opened on the plasma generator. The multiple side holes (32) are equidistant from the central hole (31).

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