Automatic calcined coke sampling device
By designing the automatic sampling device for calcined coke, using conveyor belts, material collection components, crushing components, filter mesh and drying components, the problems of low efficiency, randomness and representativeness in the prior art are solved, and calcined coke is realized The automatic random sampling and efficient processing improve the reliability of sampling and analysis detection.
Patent Information
- Application Number
- CN202411709930.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-27
- Publication Date
- 2025-02-14
AI Technical Summary
Existing calcined coke sampling mainly relies on manual random sampling, which has problems such as difficulty in guaranteeing randomness and representation and inefficiency. Especially in the case of large-scale production and frequent sampling, these problems are more prominent.
An automatic sampling device for calcined coke is designed, including a conveyor belt, material collection assembly, crushing assembly, filter mesh and drying assembly. The calcined coke is transported through the conveyor belt, and the samples are automatically grasped and crushed by rotating shafts and drive motors, and filtered through the filtering. The mesh and drying components process the samples to ensure uniformity and accuracy of the samples.
Automatic random sampling of calcined coke is realized, which improves the randomness and representativeness of sampling, reduces the subjectivity and limitations of manual operations, and improves the sampling efficiency and reliability of analysis and detection.
Smart Images
Figure CN119437769A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of calcined coke sampling, in particular to an automatic calcined coke sampling device. Background Art
[0002] With the development of society, calcined coke plays an extremely critical role in many industrial fields, especially in the aluminum electrolysis industry. As an important carbon material, calcined coke has excellent properties such as high purity, low ash content, and high conductivity. In the aluminum electrolysis process, it is widely used as an anode material. It can effectively conduct current and maintain stable physical and chemical properties under high temperature environment, providing stable energy support and a good reaction environment for the electrolytic production of aluminum.
[0003] In the production and application of calcined coke, sampling is an essential link. By sampling and analyzing calcined coke, we can accurately understand its various physical and chemical indicators, such as fixed carbon content, ash content, volatile content, resistivity, etc. These index data are extremely important for evaluating the quality grade of calcined coke, judging whether it meets the production process requirements, and optimizing the production process.
[0004] However, the existing calcined coke sampling is mainly carried out by manual random sampling, which has many serious problems. Manual sampling is difficult to ensure the randomness and representativeness of sampling. Due to the subjective factors of the operators and the limitations of the operation, the samples taken may be concentrated in certain specific areas or time periods, which cannot fully and accurately reflect the true quality status of the entire batch of calcined coke. In addition, manual sampling is inefficient and consumes a lot of manpower and time costs. This problem is more prominent in the case of large-scale production and frequent sampling. Summary of the invention
[0005] The purpose of the present invention is to solve the shortcomings in the prior art and to propose an automatic sampling device for calcined coke.
[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: an automatic sampling device for calcined coke, comprising a conveyor belt, a shell is placed on one side of the conveyor belt, a feed port is fixedly connected to the top of the shell, a material taking component is installed on the top of the feed port, a crushing component is installed inside the feed port, a filter screen is movably installed inside the feed port, the filter screen is located at the bottom of the crushing component and is installed obliquely, a support plate is fixedly connected to the front end of the filter screen, a discharge block is fixedly connected to the bottom of the support plate, the discharge block passes through the bottom of the shell, and a drying component is installed inside the shell; The material picking assembly includes a supporting ear plate, a first rotating shaft, a material picking block, a material discharge block and a first driving motor, the supporting ear plate has two fixed connections at the top of the feed port, the first rotating shaft is movably installed inside the two supporting ear plates, the material picking block is movably fixedly installed on the outer wall of the first rotating shaft, the material discharge block is fixedly connected to the top of the material picking block and is located at the top of the feed port, the first driving motor is fixedly connected to the outer wall of the supporting ear plate, the first rotating shaft is fixedly installed at the output end of the first driving motor, and the material picking block has three feed ports and is located at the top of the conveyor belt.
[0007] The crushing assembly includes a rotating cylinder, a crushing block, a gear and a second drive motor. The rotating cylinder has two movably mounted inside the outer shell. The crushing block has a plurality of ring-shaped fixed connections to the outer wall of the rotating cylinder. The crushing block fits with the outer wall of the adjacent rotating cylinder. The gear is fixedly connected to the outer wall of the crushing block. The two gears are meshed with each other. The second drive motor is fixedly mounted on the outer wall of the outer shell, and the rotating cylinder is fixedly mounted on the output end of the second drive motor.
[0008] A second rotating shaft is movably installed inside the shell, and two cams are fixedly connected to the outer wall of the second rotating shaft. The cams are fitted with the top of the filter screen, and a second driving belt is fixedly installed between the output shaft of the second driving motor and the second rotating shaft.
[0009] The inner wall of the shell is fixedly connected with a support block, and the support block has four fixed connections to the four corners of the inner wall of the shell. The top of the support block is fixedly connected with a slide rod, and the slide rod passes through the filter screen and the support plate. The top of the slide rod is fixedly connected with an upper stopper, and the upper stopper is located at the top of the filter screen and the support plate. The outer wall of the slide rod is sleeved with a spring, and the spring is located at the top of the support block.
[0010] The drying component includes a third rotating shaft, a fan, a third drive motor, a belt groove and a first drive belt, the third rotating shaft has two movably mounted inside the shell, the fan is fixedly connected to the front end of the third rotating shaft, the third drive motor is fixedly connected to the inner wall of the shell, one of the third rotating shafts is fixedly mounted on the output end of the third drive motor, the belt groove is opened on the outer wall of the third rotating shaft, the first drive belt is fixedly mounted between the two belt grooves, and the blowing end of the fan faces the filter.
[0011] An air outlet is provided at the bottom of the shell, and the air outlet is located at the bottom of the filter screen.
[0012] The inner wall of the shell is fixedly connected with a movable frame, the movable frame is located between the crushing assembly and the filter screen, and the two third rotating shafts are movably installed inside the movable frame.
[0013] The bottom of the shell is fixedly connected with a support frame, and the outer wall of the shell is fixedly installed with a protective cover.
[0014] The present invention has the following beneficial effects: 1) The present invention sets a conveyor belt, a first rotating shaft, a material taking block, a material discharging block and a first driving motor. When in use, the first driving motor starts, drives the first rotating shaft to rotate at a uniform speed, and the material taking block fixed on the outer wall of the first rotating shaft rotates synchronously therewith. When the material taking block rotates to the top of the conveyor belt, its three specially designed feed ports can be inserted into the calcined coke material being conveyed. Then, as the material taking block rotates, the material enters the feed port of the material taking block under the action of inertia and gravity, realizing the automatic grabbing and sampling of the calcined coke. As the material taking block continues to rotate, when it rotates to the top of the feed port, the material discharging block starts to play a role, and its structure can guide the sample in the material taking block to slide smoothly into the feed port, completing the material discharging process after sampling, and so on and so forth, realizing the automatic random sampling operation of the calcined coke on the conveyor belt. The present invention can automatically and randomly sample, avoid the subjectivity and limitations of manual sampling, improve the randomness and representativeness of sampling, and provide a reliable basis for subsequent accurate quality analysis.
[0015] 2) The present invention is provided with a feed port, a rotating cylinder, a crushing block, a gear, a second drive motor, a filter, a third rotating shaft, a fan, a third drive motor, a first drive belt, a second rotating shaft, a cam, a second drive belt, a spring and an exhaust port. When in use, after the sample enters the feed port, the second drive motor is started, and the second drive motor drives the rotating cylinder to rotate. The two rotating cylinders are relatively rotated through the meshing action of the gears, and the sample is crushed into small particles by the crushing block. At the same time, the second drive motor drives the second rotating shaft to rotate through the second drive belt, so that the cam rotates to push the filter. Under the synergistic action of the spring, the filter vibrates to promote the movement of the crushed sample on the filter. Next, the third drive motor is started, and the third drive motor drives the third rotating shaft to rotate. The two third rotating shafts are rotated synchronously through the first drive belt. The fan rotates to dry the sample on the filter, and the mixed gas such as hot air and water vapor is discharged from the exhaust port. The present invention breaks up samples with relatively large particles into small particles suitable for analysis and detection, and dries the particles, thereby ensuring the uniformity and accuracy of the samples in subsequent analysis processes, being conducive to more accurate determination of various indicators of calcined coke, and improving the reliability of analysis and detection results. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 It is a schematic diagram of the structure of the present invention from a first viewing angle; Figure 2 It is a schematic diagram of the structure of the second viewing angle of the present invention; Figure 3 It is a schematic diagram of the cross-sectional structure of the present invention; Figure 4 for Figure 3 The enlarged structural diagram at A in the middle; Figure 5 for Figure 3 The enlarged structural diagram at B in the middle; Figure 6 for Figure 3 The enlarged structural diagram at C in the middle; Figure 7 for Figure 3 Another perspective structural diagram; Figure 8 for Figure 7 Enlarged structural diagram at point D in the middle.
[0017] Legend: 1. Conveyor belt; 2. Shell; 3. Feed inlet; 4. Retrieving assembly; 401. Support ear plate; 402. First rotating shaft; 403. Retrieving block; 404. Discharging block; 405. First driving motor; 5. Crushing assembly; 501. Rotating drum; 502. Crushing block; 503. Gear; 504. Second driving motor; 6. Filter; 7. Drying assembly; 701. Third rotating shaft; 702. Fan; 703. Third driving motor; 704. Belt groove; 705. First driving belt; 706. Movable frame; 8. Second rotating shaft; 9. Cam; 10. Second driving belt; 11. Support block; 12. Slide bar; 13. Upper stopper; 14. Spring; 15. Support plate; 16. Discharging block; 17. Exhaust port; 18. Support frame; 19. Protective cover. DETAILED DESCRIPTION
[0018] Reference Figure 1-4The present invention provides an automatic sampling device for calcined coke, comprising a conveyor belt 1, a shell 2 is placed on one side of the conveyor belt 1, a feed port 3 is fixedly connected to the top of the shell 2, a material taking component 4 is installed on the top of the feed port 3, a crushing component 5 is installed inside the feed port 3, a filter screen 6 is movably installed inside the feed port 3, the filter screen 6 is located at the bottom of the crushing component 5 and is installed obliquely, a support plate 15 is fixedly connected to the front end of the filter screen 6, a discharge block 16 is fixedly connected to the bottom of the support plate 15, the discharge block 16 passes through the bottom of the shell 2, and a drying component 7 is installed inside the shell 2; the material taking component 4 comprises a support ear plate 401, a first rotary The rotating shaft 402, the material taking block 403, the material discharging block 404 and the first driving motor 405, the supporting ear plate 401 has two fixed connections on the top of the feed port 3, the first rotating shaft 402 is movably installed inside the two supporting ear plates 401, the material taking block 403 is movably fixedly installed on the outer wall of the first rotating shaft 402, the material discharging block 404 is fixedly connected to the top of the material taking block 403 and is located at the top of the feed port 3, the first driving motor 405 is fixedly connected to the outer wall of the supporting ear plate 401, the first rotating shaft 402 is fixedly installed on the output end of the first driving motor 405, the material taking block 403 has three feed ports and is located at the top of the conveyor belt 1.
[0019] When in use, the burnt coke is transported by the conveyor belt 1. When passing through the sampling device, the first driving motor 405 is started, driving the first rotating shaft 402 to rotate at a uniform speed, and the material taking block 403 fixed on the outer wall of the first rotating shaft 402 rotates synchronously therewith. When the material taking block 403 rotates to the top of the conveyor belt 1, its three specially designed feed ports can be inserted into the calcined coke material being transported, and then as the material taking block 403 rotates, the material enters the feed port of the material taking block 403 under the action of inertia and gravity, realizing the automatic grabbing and taking of the calcined coke. As the material taking block 403 continues to rotate, when it rotates above the feed port 3, the discharge block 404 begins to play a role. Its structure can guide the sample in the material taking block 403 to slide smoothly into the feed port 3, completing the discharge process after sampling, and this cycle is repeated to achieve the automatic random sampling operation of the calcined coke on the conveyor belt 1. Then, the sample enters the housing 2 through the feed port 3, is broken into smaller particles by the crushing component 5, and then falls on the filter screen 6, and is then dried by the drying component 7, and then discharged through the discharge block 16.
[0020] The crushing assembly 5 includes a rotating cylinder 501, a crushing block 502, a gear 503 and a second drive motor 504. The rotating cylinder 501 has two movable parts installed inside the outer shell 2. The crushing block 502 has multiple ring-shaped parts fixedly connected to the outer wall of the rotating cylinder 501. The crushing block 502 is fitted with the outer wall of the adjacent rotating cylinder 501. The gear 503 is fixedly connected to the outer wall of the crushing block 502. The two gears 503 are meshed with each other. The second drive motor 504 is fixedly installed on the outer wall of the outer shell 2, and the rotating cylinder 501 is fixedly installed on the output end of the second drive motor 504.
[0021] When in use, the second drive motor 504 is started, and the second drive motor 504 drives the rotating cylinder 501 connected thereto to start rotating. Since the gears 503 on the two rotating cylinders 501 are meshed with each other, when one rotating cylinder 501 rotates, the other rotating cylinder 501 will be caused to rotate relatively through the transmission action of the gear 503. During the rotation process, the crushing blocks 502 on the outer walls of the two rotating cylinders 501 approach, squeeze and move alternately with each other. The calcined coke sample falling from the feed port 3 is gradually broken into smaller particles under the mechanical action of the crushing blocks 502, ensuring that the particle size of the crushed sample meets the requirements of subsequent analysis and detection, thereby improving the efficiency and quality of sample processing.
[0022] A second rotating shaft 8 is movably installed inside the shell 2, and two cams 9 are fixedly connected to the outer wall of the second rotating shaft 8. The cams 9 are in contact with the top of the filter screen 6, and a second driving belt 10 is fixedly installed between the output shaft of the second driving motor 504 and the second rotating shaft 8.
[0023] When the second drive motor 504 is started, under the transmission action of the second drive belt 10, the second rotating shaft 8 starts to rotate, and the cam 9 fixed on the outer wall of the second rotating shaft 8 rotates synchronously therewith. Since the cam 9 is tightly fitted with the top of the filter screen 6, the rotation of the cam 9 will periodically push the filter screen 6, causing the filter screen 6 to vibrate up and down. This vibration effect helps the crushed calcined coke sample to move on the filter screen 6, preventing the sample from accumulating and clogging on the filter screen 6, ensuring that the sample can smoothly pass through the filter screen 6 for subsequent processing procedures, and is also beneficial to improving the contact effect between the sample and the filter screen 6 and enhancing the filtering performance.
[0024] A support block 11 is fixedly connected to the inner wall of the outer shell 2. The support block 11 has four corners fixedly connected to the inner wall of the outer shell 2. A slide rod 12 is fixedly connected to the top of the support block 11. The slide rod 12 passes through the filter screen 6 and the support plate 15. An upper stopper 13 is fixedly connected to the top of the filter screen 6 and the support plate 15. A spring 14 is sleeved on the outer wall of the slide rod 12. The spring 14 is located at the top of the support block 11.
[0025] The slide bar 12 is supported by the support block 11 and remains in a vertical fixed state. The upper stopper 13 prevents the filter screen 6 and the support plate 15 from sliding off the slide bar 12. When the cam 9 rotates to lift the filter screen 6, the spring 14 is compressed to store elastic potential energy. When the cam 9 rotates a certain angle, its lifting effect on the filter screen 6 is weakened. At this time, the spring 14 releases the elastic potential energy and pulls the filter screen 6 back to its initial position. Under the periodic rotation of the cam 9, the spring 14 cooperates with the cam 9 to make the filter screen 6 produce a stable vibration frequency and amplitude, further promoting the movement and screening process of the sample on the filter screen 6, and improving the operating stability and reliability of the entire device.
[0026] The drying component 7 includes a third rotating shaft 701, a fan 702, a third drive motor 703, a belt groove 704 and a first drive belt 705. The third rotating shaft 701 has two movable parts installed inside the shell 2. The fan 702 is fixedly connected to the front end of the third rotating shaft 701. The third drive motor 703 is fixedly connected to the inner wall of the shell 2. One of the third rotating shafts 701 is fixedly installed at the output end of the third drive motor 703. The belt groove 704 is opened on the outer wall of the third rotating shaft 701. The first drive belt 705 is fixedly installed between the two belt grooves 704. The blowing end of the fan 702 faces the filter 6.
[0027] When in use, the third drive motor 703 is started, and the third drive motor 703 drives the third rotating shaft 701 connected thereto to rotate. Under the transmission action of the first drive belt 705, the other third rotating shaft 701 also rotates synchronously, and the fan 702 fixed at the front end of the third rotating shaft 701 rotates accordingly. The airflow generated by the fan 702 is directly blown toward the calcined coke sample on the filter screen 6 to dry the sample and remove volatile impurities such as moisture in the sample, thereby ensuring the stability and accuracy of the sample in the subsequent analysis and detection process and avoiding the interference of moisture on the analysis results.
[0028] An exhaust port 17 is formed at the bottom of the housing 2 , and the exhaust port 17 is located at the bottom of the filter screen 6 .
[0029] When the fan 702 dries the sample on the filter 6, the generated mixed gas such as hot air and water vapor is smoothly discharged out of the outer shell 2 under the action of the exhaust port 17. The position and size of the exhaust port 17 are reasonably designed to ensure the rapid discharge of the gas, maintain the air circulation and air pressure balance in the outer shell 2, and prevent hot air from accumulating in the outer shell 2, affecting the drying effect and the normal operation of the device.
[0030] The inner wall of the outer shell 2 is fixedly connected with a movable frame 706 . The movable frame 706 is located between the crushing assembly 5 and the filter screen 6 . The two third rotating shafts 701 are movably installed inside the movable frame 706 .
[0031] The movable frame 706 provides a stable support and installation position for the third rotating shaft 701 , so that the third rotating shaft 701 can rotate flexibly therein, thereby ensuring the connection stability between the fan 702 and the third rotating shaft 701 .
[0032] A support frame 18 is fixedly connected to the bottom of the shell 2 , and a protective cover 19 is fixedly installed on the outer wall of the shell 2 .
[0033] The support frame 18 provides a stable support foundation for the entire device, lifting the device to a certain height off the ground, which is convenient for the installation, use and maintenance of the device. It also ensures the stability of the device during operation and prevents the normal operation of the device from being affected by factors such as uneven ground or vibration; the protective cover 19 protects the second drive motor 504 and the second drive belt to prevent damage to the device caused by external objects collision, dust pollution, etc.
[0034] Working principle: When in use, the burnt coke is transported via conveyor belt 1. When the burnt coke passes through the sampling device, the first drive motor 405 is started, and the first drive motor 405 drives the first rotating shaft 402 to rotate, so that the material taking block 403 rotates, and the material taking block 403 automatically grabs the calcined coke sample above the conveyor belt 1, and when it rotates above the feed port 3, the sample is discharged into the feed port 3 through the discharge block 404.
[0035] After the sample enters the feed port 3, the second drive motor 504 is started, and the second drive motor 504 drives the rotating cylinder 501 to rotate. The two rotating cylinders 501 rotate relatively through the meshing action of the gears 503, and the crushing block 502 is used to crush the sample into small particles.
[0036] At the same time, the second drive motor 504 drives the second rotating shaft 8 to rotate through the second drive belt 10, so that the cam 9 rotates to push the filter screen 6. Under the coordinated action of the spring 14, the filter screen 6 vibrates to promote the movement of the crushed sample on the filter screen 6.
[0037] Next, start the third drive motor 703, which drives the third rotating shaft 701 to rotate. The two third rotating shafts 701 rotate synchronously through the first drive belt 705. The fan 702 rotates to dry the sample on the filter 6, and the mixed gas such as hot air and water vapor is discharged from the exhaust port 17.
[0038] Finally, the dried and screened sample is discharged from the housing 2 through the discharge block 16 .
[0039] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.
Claims
1. A calcined coke automatic sampling device, comprising a conveyor belt (1), a housing (2) being placed on one side of the conveyor belt (1), characterized in that: A feed port (3) is fixedly connected to the top of the housing (2), a material taking assembly (4) is installed on the top of the feed port (3), a crushing assembly (5) is installed inside the feed port (3), a filter screen (6) is movably installed inside the feed port (3), the filter screen (6) is located at the bottom of the crushing assembly (5) and is installed at an angle, a support plate (15) is fixedly connected to the front end of the filter screen (6), a discharge block (16) is fixedly connected to the bottom of the support plate (15), and the discharge block (16) passes through the bottom of the housing (2), and a drying assembly (7) is installed inside the housing (2); The material taking component (4) comprises a supporting ear plate (401), a first rotating shaft (402), a material taking block (403), a material discharge block (404) and a first driving motor (405); the supporting ear plate (401) has two fixed connections at the top of the material inlet (3); the first rotating shaft (402) is movably mounted inside the two supporting ear plates (401); the material taking block (403) is movably fixedly mounted on the outer wall of the first rotating shaft (402); the material discharge block (404) is fixedly connected to the top of the material taking block (403) and is located at the top of the material inlet (3); the first driving motor (405) is fixedly connected to the outer wall of the supporting ear plate (401); the first rotating shaft (402) is fixedly mounted at the output end of the first driving motor (405); the material taking block (403) has three material inlets and is located at the top of the conveyor belt (1).
2. The automatic sampling device for calcined coke according to claim 1, characterized in that: The crushing assembly (5) comprises a rotating cylinder (501), a crushing block (502), a gear (503) and a second drive motor (504); the rotating cylinder (501) has two movably mounted inside the housing (2); the crushing block (502) has a plurality of ring-shaped fixedly connected to the outer wall of the rotating cylinder (501); the crushing block (502) is in contact with the outer wall of an adjacent rotating cylinder (501); the gear (503) is fixedly connected to the outer wall of the crushing block (502); the two gears (503) are meshed with each other; the second drive motor (504) is fixedly mounted on the outer wall of the housing (2); and the rotating cylinder (501) is fixedly mounted on the output end of the second drive motor (504).
3. The automatic sampling device for calcined coke according to claim 2, characterized in that: A second rotating shaft (8) is movably mounted inside the housing (2); two cams (9) are fixedly connected to the outer wall of the second rotating shaft (8); the cams (9) are in contact with the top of the filter screen (6); and a second driving belt (10) is fixedly mounted between the output shaft of the second driving motor (504) and the second rotating shaft (8).
4. The automatic sampling device for calcined coke according to claim 1, characterized in that: The inner wall of the outer shell (2) is fixedly connected to a support block (11), and the support block (11) has four fixedly connected to the four corners of the inner wall of the outer shell (2). The top of the support block (11) is fixedly connected to a slide bar (12), and the slide bar (12) passes through the filter screen (6) and the support plate (15). The top of the slide bar (12) is fixedly connected to an upper stopper (13), and the upper stopper (13) is located at the top of the filter screen (6) and the support plate (15). The outer wall of the slide bar (12) is provided with a spring (14), and the spring (14) is located at the top of the support block (11).
5. The automatic sampling device for calcined coke according to claim 1, characterized in that: The drying component (7) comprises a third rotating shaft (701), a fan (702), a third driving motor (703), a belt groove (704) and a first driving belt (705); the third rotating shaft (701) has two movably mounted inside the housing (2); the fan (702) is fixedly connected to the front end of the third rotating shaft (701); the third driving motor (703) is fixedly connected to the inner wall of the housing (2); one of the third rotating shafts (701) is fixedly mounted on the output end of the third driving motor (703); the belt groove (704) is opened on the outer wall of the third rotating shaft (701); the first driving belt (705) is fixedly mounted between the two belt grooves (704); and the blowing end of the fan (702) faces the filter (6).
6. The automatic sampling device for calcined coke according to claim 1, characterized in that: An air outlet (17) is provided at the bottom of the housing (2), and the air outlet (17) is located at the bottom of the filter screen (6).
7. The automatic sampling device for calcined coke according to claim 5, characterized in that: A movable frame (706) is fixedly connected to the inner wall of the outer shell (2); the movable frame (706) is located between the crushing assembly (5) and the filter screen (6); and the two third rotating shafts (701) are movably mounted inside the movable frame (706).
8. The automatic sampling device for calcined coke according to claim 1, characterized in that: A support frame (18) is fixedly connected to the bottom of the shell (2), and a protective cover (19) is fixedly mounted on the outer wall of the shell (2).