Thick plate welding device for shipbuilding and process thereof

Abstract

According to the thick plate welding device for ship manufacturing, a lantern ring is arranged on the outer side, close to a cushion layer, of a spot welding head, an inner ring is slidably connected to the interior of the lantern ring, a cushion block is arranged at the end, close to the lantern ring, of the inner ring, a spring is elastically connected to the inner side of the cushion block, a rotating ball penetrates through the outer side wall of the lantern ring in a hinged mode, and fan blades are connected to one side of the rotating ball in a swinging mode; the sleeve ring is located below the cushion layer, the sleeve ring is in a circular ring shape, the interior of the sleeve ring is hollow, the sleeve ring is located in the protective cover, the spring drives the cushion block to elastically slide in the vertical direction through movement and vibration of the spot welding head, and the inner ring slides in the vertical direction through the cushion block and the spring. Therefore, the inner ring can drive the rotating ball to swing in the vertical direction, the rotating ball synchronously drives the fan blades to swing, and the fluidity of smoke in the protective cover can be improved in the swing process of the fan blades.

Description

Technical Field

[0001] The invention relates to the technical field of brazing or desoldering, in particular to a thick plate welding device and a process thereof for shipbuilding. Background Art

[0002] Shipbuilding requires the use of thick plate welding, and thick plates are produced from special structural steel for shipbuilding. Thick plates are welded together using welding devices. The welding device uses the high-temperature arc generated when the positive and negative poles are short-circuited to melt the solder on the welding rod and the thick plate to achieve the purpose of combining the contacted objects. This is a technical inspiration for welding devices; Research on welding devices found the following problems: The welding device uses a welding head to weld thick plates for shipbuilding. Since the thick plates are usually made of steel plates, a large amount of smoke is easily generated at the welding point between the welding head and the thick plate during the metal welding process. The smoke contains a large amount of dust particles, and the dust particles splash, which easily causes a large dust content inside the welding workshop, thereby causing the welding device to be unable to quickly filter the smoke generated after welding during the welding process; At present, CN202310808075.1 in the prior art discloses a ship steel plate welding device, which includes a welding machine and a welding clamp, which is connected to the welding machine and also includes a cone-shaped cover body, the lower end of the cover body has a cover opening, the upper end of the cover body has an exhaust port, the lower end of the cover body is fixedly connected to a plurality of magnets, the lower end of the cover body is also connected to a plurality of rollers, the bottom surface of the rollers is lower than the bottom surface of the cover body, the bottom surface of the magnets is higher than the bottom surface of the rollers, and the side of the cover body is provided with a first operating port, the cover body is placed on the ship steel plate, the magnets rely on the suction force of the steel plate to make the cover body adsorbed on the steel plate, the staff pushes and pulls the cover body according to the position to be welded, so that the cover body moves to cover the position to be welded, holds the welding clamp and extends it from the first operating port, and welds on the position to be welded, the cover body can block the wind from the outside from blowing to the position to be welded, and the position to be welded is protected from wind in all directions, compared with the prior art, the windproof effect of the welding area is improved, and it is convenient to disassemble and transfer the position; The present invention can mainly solve the problem that the welding device cannot quickly filter the fume generated after welding during the welding process. Summary of the invention

[0003] The object of the present invention is to provide a thick plate welding device and process for shipbuilding.

[0004] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a thick plate welding device for shipbuilding and a process thereof, comprising a welding machine, a welding table is provided at the upper end of the welding machine, a three-axis workbench is provided on the side of the upper end of the welding machine close to the welding table, a motor is provided at the end of the three-axis workbench, and a spot welding head is slidably connected to one end of the three-axis workbench close to the welding table.

[0005] As a further solution of the present invention: a transformer coil and a circuit board are provided inside the welding machine, and both the transformer coil and the circuit board are connected to the spot welding head loop.

[0006] As a further solution of the present invention: a numerical control panel is provided at one end of the three-axis workbench, the motor is connected to the power supply circuit through a power line, and the motor is connected to the numerical control panel circuit through an electric wire.

[0007] As a further solution of the present invention: the outer side of the spot welding head is surrounded by a protective cover, the outer side of the spot welding head close to the protective cover is surrounded by a cushion layer, the outer side of the spot welding head close to the cushion layer is surrounded by a water tank, and an outlet pipe runs through one end of the water tank close to the cushion layer.

[0008] As a further solution of the present invention: the protective cover is spirally connected to the outer side of the spot welding head, and the protective cover is semicircular.

[0009] As a further solution of the present invention: the side of the water tank is concave, the water outlet pipe is distributed around the lower end of the water tank, the diameter of the water outlet hole inside the water outlet pipe is 0.2-0.5cm, and the water outlet pipe is vertically corresponding to the cushion layer.

[0010] As a further solution of the present invention: the cushion layer and the water tank are both located on the inner side of the protective cover, and the cushion layer is made of sponge material.

[0011] As a further solution of the present invention: a ring is provided on the outer side of the spot welding head close to the cushion layer, an inner ring is slidably connected to the inside of the ring, a pad is provided on one end of the inner ring close to the ring, a spring is elastically connected to the inner side of the pad, a rotating sphere is hingedly penetrated through the outer wall of the ring, and a fan blade is swingably connected to one side of the rotating sphere.

[0012] As a further solution of the present invention: the collar is located below the cushion layer, is in a circular ring shape, is hollow inside, and is located inside the protective cover.

[0013] As a further solution of the present invention: the outer wall of the inner ring is in vertical sliding friction with one side of the rotating sphere, the inner ring is vertically elastically connected to the spring through a pad, and the height of the inner ring is one third of the inner height of the collar.

[0014] As a further solution of the present invention: the cushion blocks are located at both ends of the spring, and 6-8 sets of cushion blocks and springs are matched, and the cushion block at the lower end of the spring is installed inside the collar.

[0015] As a further solution of the present invention: the side of the rotating sphere away from the fan blades extends to the inside of the ring, the rotating sphere and the fan blades are connected in a vertical swinging manner, and when the rotating sphere is not rotating, the fan blades swing downward at one end of the rotating sphere.

[0016] As a further solution of the present invention: the process comprises the following steps: S1: The protective cover is spirally connected to the outer side of the spot welding head, which makes it easy to remove the protective cover from the outer side of the spot welding head, and then to add clean water to the inside of the water tank; S2: The thick plate is placed on the upper end of the welding table. The motor is programmed according to the numerical control system used by the numerical control panel. Then the motor is operated through the electric control signal. The three-axis worktable first moves to the specified position along the Y axis, and then the spot welding head moves to the processing starting point along the X axis. At the same time, the three-axis worktable descends along the Z axis. The transformer coil and the circuit board are connected to the spot welding head circuit. The spot welding head uses the high-temperature arc generated when the positive and negative poles are short-circuited in an instant to melt the solder on the welding rod and the thick plate. The spot welding head contacts the thick plate and starts welding. S3: The protective cover surrounds the outside of the spot welding head, and the smoke generated during the spot welding head welding thick plates can enter the inside of the protective cover; S4: The clean water inside the water tank drips into the inside of the cushion through the outlet pipe, and the cushion is inside the protective cover, so the smoke enters the inside of the cushion, and the dust inside the smoke can be filtered and absorbed by the cushion; S5: By utilizing the movement and vibration of the spot welding head, the spring drives the pad to slide elastically in the vertical direction, and the inner ring slides in the vertical direction through the pad and the spring. Since the outer wall of the inner ring slides vertically with one side of the rotating sphere, the inner ring can drive the rotating sphere to swing in the vertical direction; S6: The rotating sphere drives the fan blades to swing synchronously, and the smoke flow inside the protective cover can be increased during the swinging process of the fan blades. Beneficial Effects

[0017] 1. The protective cover surrounds the outside of the spot welding head, and the fume generated during the spot welding head welding thick plates can enter the inside of the protective cover. The inside of the water tank is filled with clean water, and the clean water drips into the inside of the cushion through the outlet pipe. The cushion is inside the protective cover, so the fume enters the inside of the cushion, and the dust inside the fume can be filtered and absorbed by the cushion to prevent the dust inside the fume from splashing into the air, so that this welding device can achieve the effect of dust reduction; 2. The spot welding head moves vertically or horizontally through the three-axis worktable. The spot welding head generates vibration when welding thick plates. The movement and vibration of the spot welding head are used to drive the pad to slide elastically in the vertical direction. The inner ring slides vertically through the pad and the spring. Since the outer wall of the inner ring slides vertically with one side of the rotating sphere, the inner ring can drive the rotating sphere to swing in the vertical direction. The rotating sphere simultaneously drives the fan blades to swing. During the swinging process of the fan blades, the fluidity of the smoke inside the protective cover can be increased to prevent the smoke from accumulating inside the protective cover, thereby assisting the smoke to pass through the cushion layer to form filtration and purification. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1It is a schematic diagram of the overall structure of the present invention.

[0019] Figure 2 It is a schematic diagram of the overall structure explosion of the present invention.

[0020] Figure 3 It is a schematic diagram of the three-axis workbench of the present invention.

[0021] Figure 4 It is a schematic diagram of a spot welding head assembly of the present invention.

[0022] Figure 5 It is a schematic diagram of an explosion of a spot welding head assembly of the present invention.

[0023] Figure 6 It is a schematic diagram of the explosion of the internal structure of the protective cover of the present invention.

[0024] Figure 7 It is a schematic diagram of the explosion of the collar assembly of the present invention.

[0025] Figure 8 It is a schematic diagram of the cushion block structure of the present invention.

[0026] Figure 1-8 In: 1- welding machine, 101- welding table, 102- three-axis workbench, 103- motor, 104- spot welding head, 2- protective cover, 201- sleeve ring, 202- inner ring, 203- rotating sphere, 204- fan blade, 3- pad, 301- spring, 4- water tank, 401- outlet pipe, 402- cushion. DETAILED DESCRIPTION

[0027] See also Figure 1-8 In the embodiment of the present invention, Embodiment 1: A thick plate welding device and process for shipbuilding, comprising a welding machine 1, wherein a welding platform 101 is provided at the upper end of the welding machine 1, a three-axis workbench 102 is provided at one side of the upper end of the welding machine 1 close to the welding platform 101, a motor 103 is provided at the end of the three-axis workbench 102, and a spot welding head 104 is slidably connected to one end of the three-axis workbench 102 close to the welding platform 101; Among them: welding machine 1, the welding machine 1 is provided with a transformer coil and a circuit board inside, and the transformer coil and the circuit board are connected to the spot welding head 104 circuit; The transformer coil and the circuit board are both connected to the spot welding head 104 circuit. The spot welding head 104 uses the high-temperature arc generated when the positive and negative poles are short-circuited instantly to melt the solder on the welding rod and the thick plate. A three-axis workbench 102, one end of which is provided with a numerical control panel, a motor 103 is connected to a power supply circuit via a power line, and the motor 103 is connected to a numerical control panel circuit via an electric wire; The motor 103 is programmed with a processing program according to the numerical control system used by the numerical control panel, and then the motor 103 is operated through an electric control signal, and the motor 103 drives the various components of the three-axis workbench 102 to move in coordination, thereby driving the spot welding head 104 to move; Wherein: the thick plate is placed on the upper end of the welding table 101, the motor 103 is programmed with a processing program according to the numerical control system adopted by the numerical control panel, and then the motor 103 is operated through an electric control signal, the three-axis workbench 102 first moves to a specified position along the Y axis, and then the spot welding head 104 moves to the processing starting point along the X axis, and at the same time the three-axis workbench 102 descends along the Z axis, and is connected to the spot welding head 104 loop through the transformer coil and the circuit board, and the spot welding head 104 uses the high-temperature arc generated when the positive and negative poles are short-circuited in an instant to melt the solder on the welding rod and the thick plate, so that the spot welding head 104 contacts the thick plate and starts welding, completing the welding process of the thick plate by this welding device; Example 2: Refer to the attached manual Figure 3-6 It can be seen that the difference between Example 2 and Example 1 is that the outer side of the spot welding head 104 is surrounded by a protective cover 2, the outer side of the spot welding head 104 close to the protective cover 2 is surrounded by a cushion layer 402, the outer side of the spot welding head 104 close to the cushion layer 402 is surrounded by a water tank 4, and one end of the water tank 4 close to the cushion layer 402 is penetrated by a water outlet pipe 401; Wherein: the protective cover 2 is spirally connected to the outer side of the spot welding head 104, and the protective cover 2 is semicircular; By surrounding the outer side of the spot welding head 104 with the protective cover 2, the smoke generated during the thick plate welding process of the spot welding head 104 can enter the interior of the protective cover 2; The protective cover 2 is spirally connected to the outer side of the spot welding head 104, so that the protective cover 2 can be easily taken out from the outer side of the spot welding head 104, and then it is convenient to add clean water into the water tank 4; The water tank 4 and the water outlet pipe 401, the side of the water tank 4 is concave, the water outlet pipe 401 is distributed around the lower end of the water tank 4, the diameter of the water outlet hole inside the water outlet pipe 401 is 0.2-0.5cm, and the water outlet pipe 401 is vertically corresponding to the cushion layer 402; The cushion layer 402, the cushion layer 402 and the water tank 4 are both located on the inner side of the protective cover 2, and the cushion layer 402 is made of sponge; Wherein: the protective cover 2 surrounds the outside of the spot welding head 104, and the smoke generated during the spot welding head 104 welding thick plates can enter the interior of the protective cover 2, and the interior of the water tank 4 is filled with clean water, and the clean water drips into the interior of the cushion layer 402 through the water outlet pipe 401, and the cushion layer 402 is inside the protective cover 2, so the smoke enters the interior of the cushion layer 402, and the dust inside the smoke can be filtered and absorbed by the cushion layer 402, so as to prevent the dust inside the smoke from splashing into the air, so that the welding device can achieve the effect of dust reduction; Example 3: Refer to the attached manual Figure 4-8It can be known that the difference between Example 3 and Example 1-2 is that a ring 201 is provided on the outer side of the spot welding head 104 close to the cushion layer 402, an inner ring 202 is slidably connected inside the ring 201, a cushion block 3 is provided at one end of the inner ring 202 close to the ring 201, a spring 301 is elastically connected to the inner side of the cushion block 3, a rotating sphere 203 is hingedly penetrated through the outer wall of the ring 201, and a fan blade 204 is swingably connected to one side of the rotating sphere 203; Wherein: the collar 201, the collar 201 is located below the cushion layer 402, the collar 201 is in a circular ring shape, the inside of the collar 201 is hollow, and the collar 201 is located inside the protective cover 2; When the protective cover 2 is spirally connected to the outer side of the spot welding head 104, the collar 201 is located on the inner side of the protective cover 2. Figure 4 As shown; Inner ring 202, the outer wall of inner ring 202 is in vertical sliding friction with one side of rotating sphere 203, inner ring 202 is vertically elastically connected with spring 301 through pad 3, and the height of inner ring 202 is one third of the inner height of sleeve ring 201; The height of the inner ring 202 is one third of the inner height of the sleeve ring 201, so that the inner ring 202 can slide vertically inside the sleeve ring 201. The pad 3 and the spring 301, the pad 3 is located at both ends of the spring 301, and the pad 3 and the spring 301 are matched with 6-8 sets, and the pad 3 at the lower end of the spring 301 is installed inside the collar 201; The pads 3 and springs 301 are matched with 6-8 groups, and each group is evenly arranged at the lower end of the inner ring 202; The rotating sphere 203 and the fan blade 204, the side of the rotating sphere 203 away from the fan blade 204 extends to the inside of the ring 201, the rotating sphere 203 and the fan blade 204 are vertically swingingly connected, and when the rotating sphere 203 is not rotating, the fan blade 204 swings downward at one end of the rotating sphere 203; The weight of the fan blade 204 is 2-5g, and it is convenient to utilize the friction of the inner ring 202 to drive the fan blade 204 to swing in a vertical direction through the rotating sphere 203; Among them: the spot welding head 104 moves in a vertical direction or a horizontal direction through the three-axis workbench 102, and the spot welding head 104 generates vibration when welding the thick plate. By utilizing the movement and vibration of the spot welding head 104, the spring 301 drives the pad 3 to slide elastically in the vertical direction, and the inner ring 202 slides in the vertical direction through the pad 3 and the spring 301. Since the outer wall of the inner ring 202 and one side of the rotating sphere 203 are in vertical sliding friction, the inner ring 202 can drive the rotating sphere 203 to swing in the vertical direction, and the rotating sphere 203 synchronously drives the fan blades 204 to swing. During the swinging process of the fan blades 204, the smoke flowability inside the protective cover 2 can be increased to prevent the smoke from accumulating inside the protective cover 2, thereby assisting the smoke to pass through the cushion layer 402 to form filtering and purification; Example

[0028] The process includes the following steps: S1: The protective cover 2 is spirally connected to the outer side of the spot welding head 104, so that the protective cover 2 can be easily taken out from the outer side of the spot welding head 104, and then it is convenient to add clean water into the water tank 4; S2: The thick plate is placed on the upper end of the welding table 101, and the motor 103 is programmed with a processing program according to the numerical control system used by the numerical control panel, and then the motor 103 is operated through an electric control signal, and the three-axis workbench 102 first moves to a specified position along the Y axis, and then the spot welding head 104 moves to the processing starting point along the X axis, and at the same time the three-axis workbench 102 descends along the Z axis, and is connected to the spot welding head 104 circuit through the transformer coil and the circuit board, and the spot welding head 104 uses the high-temperature arc generated when the positive and negative poles are short-circuited for an instant to melt the solder on the welding rod and the thick plate, and the spot welding head 104 contacts the thick plate and starts welding; S3: The protective cover 2 surrounds the outer side of the spot welding head 104, so that the smoke generated during the welding of the thick plate by the spot welding head 104 can enter the interior of the protective cover 2; S4: the clean water in the water tank 4 drips into the inside of the cushion layer 402 through the water outlet pipe 401, and the cushion layer 402 is inside the protective cover 2, so the smoke enters the inside of the cushion layer 402, and the dust inside the smoke can be filtered and absorbed by the cushion layer 402; S5: By utilizing the movement and vibration of the spot welding head 104, the spring 301 drives the pad 3 to slide elastically in the vertical direction, and the inner ring 202 slides in the vertical direction through the pad 3 and the spring 301. Since the outer wall of the inner ring 202 and one side of the rotating sphere 203 are in vertical sliding friction, the inner ring 202 can drive the rotating sphere 203 to swing in the vertical direction; S6: The rotating sphere 203 synchronously drives the fan blades 204 to swing, and the fan blades 204 can increase the smoke flowability inside the protective cover 2 during the swinging process; Through the above steps, during the welding process, the protective cover 2 can prevent the smoke from drifting away, and at the same time, the swing of the fan blades 204 drives the smoke to flow, making it easier for the smoke to be filtered through the cushion layer 402.

[0029] The above are only preferred embodiments of the present invention. It should be pointed out that, for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention. These should also be regarded as the protection scope of the present invention. These will not affect the effect of the implementation of the present invention and the practicality of the patent.

Claims

1. A thick plate welding device for shipbuilding, characterized in that: include A welding machine (1), wherein a welding platform (101) is provided at the upper end of the welding machine (1), a three-axis workbench (102) is provided at one side of the upper end of the welding machine (1) close to the welding platform (101), a motor (103) is provided at the end of the three-axis workbench (102), and a spot welding head (104) is slidably connected to one end of the three-axis workbench (102) close to the welding platform (101); A transformer coil and a circuit board are provided inside the welding machine (1), and both the transformer coil and the circuit board are connected to a circuit of a spot welding head (104); A protective cover (2), the protective cover (2) surrounds the outer side of the spot welding head (104); The protective cover (2) is spirally connected to the outer side of the spot welding head (104), and the protective cover (2) is semicircular.

2. A thick plate welding device for shipbuilding according to claim 1, characterized in that: The welding machine (1) is provided with a transformer coil and a circuit board inside, and the transformer coil and the circuit board are both connected to the circuit of the spot welding head (104); A three-axis workbench (102) is provided with a numerical control panel at one end of the three-axis workbench (102), a motor (103) is connected to a power supply circuit via a power line, and the motor (103) is connected to a numerical control panel circuit via an electric wire.

3. A thick plate welding device for shipbuilding according to claim 1, characterized in that: The spot welding head (104) is surrounded by a cushion layer (402) on the outside of the protective cover (2), the spot welding head (104) is surrounded by a water tank (4) on the outside of the cushion layer (402), and a water outlet pipe (401) is passed through one end of the water tank (4) close to the cushion layer (402).

4. A thick plate welding device for shipbuilding according to claim 3, characterized in that: The side of the water tank (4) is concave, and the water outlet pipe (401) is distributed around the lower end of the water tank (4). The diameter of the water outlet hole inside the water outlet pipe (401) is 0.2-0.5 cm, and the water outlet pipe (401) is vertically corresponding to the cushion layer (402).

5. A thick plate welding device for shipbuilding according to claim 3, characterized in that: The cushion layer (402) and the water tank (4) are both located on the inner side of the protective cover (2).

6. A thick plate welding device for shipbuilding according to claim 1, characterized in that: The spot welding head (104) is provided with a collar (201) on the outside close to the cushion layer (402); the collar (201) is slidably connected to an inner ring (202); a cushion block (3) is provided on one end of the inner ring (202) close to the collar (201); a spring (301) is elastically connected to the inside of the cushion block (3); a rotating sphere (203) is hingedly penetrated through the outer wall of the collar (201); and a fan blade (204) is swingably connected to one side of the rotating sphere (203).

7. A thick plate welding device for shipbuilding according to claim 6, characterized in that: The collar (201) is located below the cushion layer (402), the collar (201) is in a circular ring shape, the interior of the collar (201) is hollow, and the collar (201) is located inside the protective cover (2).

8. A thick plate welding device for shipbuilding according to claim 6, characterized in that: The outer wall of the inner ring (202) is in vertical sliding friction with one side of the rotating sphere (203), the inner ring (202) is vertically elastically connected to the spring (301) via the cushion block (3), and the height of the inner ring (202) is one third of the inner height of the sleeve ring (201).

9. A thick plate welding device for shipbuilding according to claim 6, characterized in that: The cushion blocks (3) are located at both ends of the spring (301), and 6 to 8 sets of cushion blocks (3) and springs (301) are provided in a matching manner. The cushion block (3) at the lower end of the spring (301) is installed inside the collar (201); The pads (3) and springs (301) are matched to form 6 to 8 groups, and each group is evenly arranged at the lower end of the inner ring (202); The rotating sphere (203) and the fan blade (204) are connected to the rotating sphere (203) and the fan blade (204). The side of the rotating sphere (203) away from the fan blade (204) extends to the inside of the ring (201). The rotating sphere (203) and the fan blade (204) are connected to each other in a vertical swinging manner. When the rotating sphere (203) is not rotating, the fan blade (204) swings downward at one end of the rotating sphere (203).

10. A process for a thick plate welding device for shipbuilding, characterized in that According to the thick plate welding device for shipbuilding described in claims 1-9, the process includes the following steps: S1: The protective cover (2) is spirally connected to the outer side of the spot welding head (104), so that the protective cover (2) can be easily removed from the outer side of the spot welding head (104), thereby facilitating the addition of clean water into the water tank (4); S2: The thick plate is placed on the upper end of the welding table (101), and the motor (103) is programmed with a processing program according to the numerical control system used by the numerical control panel, and then the motor (103) is operated through an electric control signal, and the three-axis worktable (102) first moves to a specified position along the Y axis, and then the spot welding head (104) moves to the processing starting point along the X axis, and at the same time, the three-axis worktable (102) descends along the Z axis, and is connected to the spot welding head (104) circuit through the transformer coil and the circuit board. The spot welding head (104) uses the high-temperature arc generated when the positive and negative poles are short-circuited instantly to melt the solder on the welding rod and the thick plate, and the spot welding head (104) contacts the thick plate and starts welding; S3: The protective cover (2) surrounds the outer side of the spot welding head (104), so that the smoke generated during the welding process of the spot welding head (104) on the thick plate can enter the interior of the protective cover (2); S4: clean water in the water tank (4) drips into the interior of the cushion layer (402) through the water outlet pipe (401), and the cushion layer (402) is located inside the protective cover (2), so that smoke enters the interior of the cushion layer (402), and dust inside the smoke is filtered and absorbed by the cushion layer (402); S5: By utilizing the movement and vibration of the spot welding head (104), the spring (301) drives the pad (3) to slide elastically in a vertical direction, and the inner ring (202) slides in a vertical direction through the pad (3) and the spring (301). Since the outer wall of the inner ring (202) and one side of the rotating sphere (203) are in vertical sliding friction, the inner ring (202) can drive the rotating sphere (203) to swing in a vertical direction; S6: The rotating sphere (203) synchronously drives the fan blades (204) to swing, and the smoke flowability inside the protective cover (2) can be increased during the swinging process of the fan blades (204).

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