Suction type composite gas detector for granary

Abstract

The invention relates to the technical field of gas sampling, and discloses a suction type composite gas detector for a granary, the suction type composite gas detector comprises a detector case and a plurality of external fixed-point sampling and sucking mechanisms, the gas inlet end of the detector case is connected with the external fixed-point sampling and sucking mechanisms; the external fixed-point sampling and sucking mechanism comprises a sampling outer pipe, a sampling inner pipe and a driving part, the sampling outer pipe and the sampling inner pipe are linked through the driving part, and the sampling inner pipe is nested and movably arranged in the inner space of the sampling outer pipe; through the nested structure of the sampling outer pipe and the sampling inner pipe and the control of the driving piece, the flexibility and diversity of gas sample collection are realized, and the design allows the main extraction opening and the auxiliary extraction opening to be alternately aligned with the auxiliary sampling opening and the main sampling opening according to requirements, so that gas samples can be sucked from different heights of the granary, and the sampling efficiency is improved. By means of the function, the accuracy and comprehensiveness of gas detection are greatly improved, and potential problem areas in the granary can be found and positioned in time.

Description

Technical Field

[0001] The invention relates to the field of gas sampling, and more particularly to an inhalation type composite gas detector for a granary. Background Art

[0002] As an important strategic material, the safe storage of grain is of great significance to the national economy and social stability. During the grain storage process, due to the respiration and microbial activity of grain, harmful gases such as hydrogen sulfide, carbon dioxide, methane, and ammonia may be produced. The accumulation of these gases will not only lead to the deterioration of grain quality, mildew, and insects, but also pose a serious threat to the health and safety of warehouse managers. Therefore, it is necessary to use grain silo gas detectors for monitoring.

[0003] At present, fixed gas detectors are widely used in granaries. These detectors are usually installed at fixed positions in the silo to continuously monitor the gas concentration in a specific area. They can only extract gas at the same height for detection;

[0004] However, due to the different qualities of different harmful gases, their distribution locations in the warehouse will also be different. It may not be possible to accurately capture the true concentration of all harmful gases and provide warehouse managers with reliable safety warnings and decision-making basis. For this reason, we propose an inhalation composite gas detector for granaries. Summary of the invention

[0005] The present invention provides an inhalation type composite gas detector for a granary, which solves the technical problem in the related art that due to the different masses of different harmful gases, their distribution positions in the warehouse may also be different, and the true concentration of all harmful gases may not be accurately captured.

[0006] The present invention provides a suction type composite gas detector for a granary, comprising a detector chassis and a plurality of external fixed-point suction and collection mechanisms, wherein the air inlet end of the detector chassis is connected to the external fixed-point suction and collection mechanisms;

[0007] The external fixed-point sampling mechanism includes a sampling outer tube, a sampling inner tube and a driving member. The sampling outer tube and the sampling inner tube are linked by the driving member, and the sampling inner tube is nested and movably arranged in the inner space of the sampling outer tube.

[0008] The side wall of the sampling outer tube is provided with a secondary sampling port and a main sampling port, both of which are located in the same side wall area; the side wall of the sampling inner tube is provided with a main air extraction port and a secondary air extraction port, the main air extraction port and the secondary air extraction port are respectively located on different side walls of the sampling inner tube, the main air extraction port is aligned with the main sampling port in the vertical direction, and the secondary sampling port is also aligned with the secondary air extraction port in the vertical direction;

[0009] Through the control of the driving part, the sampling inner tube rotates around its axis, and then the main air suction port and the auxiliary air suction port are alternately aligned with the auxiliary sampling port and the main sampling port respectively, and gas samples are sucked in from different heights of the granary.

[0010] Furthermore, the detector chassis includes a gas detection component, the detection end of the gas detection component is connected to an active suction pump, the air inlet end of the active suction pump is connected to a junction box, the air inlet end of the junction box is provided with a number of solenoid valves, and the several solenoid valves are all connected to a main air inlet pipe, the gas detection component, the active suction pump and the solenoid valve are all controlled by the intelligent system of the detector chassis, and the end of the main air inlet pipe away from the detector chassis is distributed at different positions of the granary according to actual needs.

[0011] Furthermore, the external fixed-point sampling and suction mechanism also includes an installation box, on which a mounting part is fixed, and the installation box is fixed at different positions of the ceiling of the granary through the mounting part, a turntable is rotatably arranged inside the installation box, a winding belt is arranged on the turntable, and a limiting cylinder is fixedly arranged below the turntable, and the bottom end of the limiting cylinder is fixedly connected to the top end of the sampling outer tube.

[0012] Furthermore, an auxiliary control mechanism is provided at one end of the reel away from the installation box, the auxiliary control mechanism includes an auxiliary control box, and the auxiliary control box is installed on the wall near the granary door, a slide plate is slidably provided inside the auxiliary control box, a binding rope part running through the auxiliary control box is fixedly provided on one side of the slide plate, a pull rope is fixedly provided on the side of the slide plate away from the binding rope part, the binding rope part is connected to the reel, and the pull rope is connected to the inner wall of the granary door.

[0013] Furthermore, the driving part includes a mixing box, a piston is slidably arranged inside the mixing box, a guide column is passed through the center position of the piston, an elastic band and a pull belt are fixedly arranged on the side of the piston away from the air outlet end of the mixing box, and there are several elastic bands, and the ends of the several elastic bands away from the piston are fixedly connected to the guide column, and the air outlet end of the mixing box is connected to the main air inlet pipe.

[0014] Furthermore, the upper and lower walls of the mixing box are respectively provided with through pipe one and through pipe two, the air inlet ends of through pipe one and through pipe two are interconnected and connected to the air outlet end of the sampling inner tube, and the air outlet end of through pipe one is located on the left side of the air outlet end of through pipe two.

[0015] Furthermore, a driving cylinder is fixedly provided at one end of the pull belt away from the mixing box, a threaded strip is fixedly provided on the inner wall of the driving cylinder, a driving disk is rotatably provided inside the driving cylinder, a threaded groove is provided on the outer wall of the driving disk, the threaded groove is engaged with the threaded strip, and the driving disk is fixedly connected to the top end of the sampling inner tube.

[0016] Furthermore, a semi-cylindrical rotating block is fixedly provided at the bottom end of the sampling inner tube, an air bag is provided on one side of the rotating block, and the air bag is fixed to the sampling outer tube, and the air bag is squeezed by the rotation of the rotating block to discharge the gas.

[0017] Furthermore, a blocking balloon 1 and a blocking balloon 2 are fixedly provided on the inner wall of the sampling inner tube. Both the blocking balloon 1 and the blocking balloon 2 are connected to the airbag through a hose, and the blocking balloon 1 is located above the blocking balloon 2.

[0018] Furthermore, a sampling window is provided on the outer wall of the sampling inner tube on the same side of the main air extraction port, and the height of the sampling window is located between blocking balloon one and blocking balloon two. A sampling port is provided on the outer wall of the sampling outer tube, and the sampling port and the sampling window are located at the same height.

[0019] The beneficial effects of the present invention are:

[0020] The present invention realizes the flexibility and diversity of gas sample collection through the nested structure of the sampling outer tube and the sampling inner tube and the control of the driving member. The design allows the main gas extraction port and the auxiliary gas extraction port to be alternately aligned with the auxiliary sampling port and the main sampling port as needed, so that gas samples can be sucked in from different heights of the granary. This function greatly improves the accuracy and comprehensiveness of gas detection, and helps to timely discover and locate potential problem areas in the granary;

[0021] The suction-type composite gas detector adopts multiple external fixed-point sampling and suction mechanisms. These external fixed-point sampling and suction mechanisms are not only widely distributed, covering various key positions of the granary, but each mechanism has independent and flexible sampling capabilities. The setting of multiple external fixed-point sampling and suction mechanisms also greatly improves the efficiency and reliability of gas monitoring. They can perform gas extraction detection in turn to form an all-round, three-dimensional monitoring network for the internal gas environment of the granary. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0023] Figure 2 It is a schematic diagram of the structure of the gas detection element of the present invention;

[0024] Figure 3 It is a schematic diagram of the structure of the turntable of the present invention;

[0025] Figure 4 It is a schematic diagram of the structure of the sampling outer tube of the present invention;

[0026] Figure 5 It is a schematic diagram of the internal structure of the installation box of the present invention;

[0027] Figure 6 It is a schematic diagram of the internal structure of the gas mixing box of the present invention;

[0028] Figure 7 It is a schematic diagram of the internal structure of the limiting cylinder of the present invention;

[0029] Figure 8It is a schematic diagram of the structure of the sampling inner tube of the present invention;

[0030] Fig. 9 It is a schematic diagram of the internal structure of the sampling inner tube of the present invention;

[0031] Fig.10 It is a schematic diagram of the internal structure of the auxiliary control box of the present invention.

[0032] In the figure: 11, detector chassis; 12, junction box; 13, solenoid valve; 14, main air inlet pipe; 15, active suction pump; 16, gas detection component; 2, external fixed-point sampling and suction mechanism; 21, installation box; 22, turntable; 23, limit cylinder; 24, sampling outer tube; 25, auxiliary sampling port; 26, main sampling port; 27, tape; 28, sampling port; 29, installation component; 31, sampling inner tube; 32, main air extraction port; 33, mixing box; 34, through pipe 1; 35 , through pipe 2; 36, piston; 37, guide column; 38, elastic band; 39, drawstring; 301, drive cylinder; 302, drive disk; 303, threaded strip; 304, threaded groove; 305, auxiliary air suction port; 306, rotating block; 307, air bag; 308, blocking balloon 1; 309, blocking balloon 2; 3001, sampling window; 4, auxiliary control mechanism; 41, auxiliary control box; 42, slide plate; 43, pull rope; 44, rope binding piece; 3002, electric control valve. DETAILED DESCRIPTION

[0033] The subject matter described herein will now be discussed with reference to example embodiments. It should be understood that the discussion of these embodiments is only to enable those skilled in the art to better understand and implement the subject matter described herein, and the functions and arrangements of the elements discussed may be changed without departing from the scope of protection of the contents of this specification. Each example may omit, replace or add various processes or components as needed. In addition, the features described relative to some examples may also be combined in other examples.

[0034] like Figure 1 , Figure 2 , Figure 4 and Figure 5 As shown, a suction-type composite gas detector for a granary includes a detector chassis 11 and a plurality of external fixed-point suction mechanisms 2, wherein the air inlet end of the detector chassis 11 is connected to the external fixed-point suction mechanisms 2;

[0035] The external fixed-point sampling mechanism 2 includes a sampling outer tube 24, a sampling inner tube 31 and a driving member. The sampling outer tube 24 and the sampling inner tube 31 are linked by the driving member. The sampling inner tube 31 is nested and movably arranged in the inner space of the sampling outer tube 24.

[0036] The side wall of the sampling outer tube 24 is provided with a secondary sampling port 25 and a main sampling port 26, both of which are located in the same side wall area. The side wall of the sampling inner tube 31 is provided with a main air extraction port 32 and a secondary air extraction port 305, which are respectively located on different side walls of the sampling inner tube 31. The main air extraction port 32 is aligned with the main sampling port 26 in the vertical direction, and the secondary sampling port 25 is also aligned with the secondary air extraction port 305 in the vertical direction.

[0037] Through the control of the driving member, the sampling inner tube 31 rotates around its axis, so that the main air suction port 32 and the auxiliary air suction port 305 are alternately aligned with the auxiliary sampling port 25 and the main sampling port 26 respectively, and gas samples are sucked in from different heights of the granary.

[0038] The flexibility and diversity of gas sample collection are achieved through the nested structure of the sampling outer tube 24 and the sampling inner tube 31 and the control of the driving member. The design allows the main gas extraction port 32 and the auxiliary gas extraction port 305 to be alternately aligned with the auxiliary sampling port 25 and the main sampling port 26 as needed, so that gas samples can be sucked in from different heights of the granary. This function greatly improves the accuracy and comprehensiveness of gas detection, and helps to timely discover and locate potential problem areas in the granary, such as local accumulation of harmful gases.

[0039] A suction-type composite gas detector adopts multiple external fixed-point sampling and suction mechanisms 2. These external fixed-point sampling and suction mechanisms 2 are not only widely distributed, covering various key positions of the granary, but also each mechanism has independent and flexible sampling capabilities. The setting of multiple external fixed-point sampling and suction mechanisms 2 also greatly improves the efficiency and reliability of gas monitoring. They can perform gas extraction detection in turn to form an all-round, three-dimensional monitoring network for the internal gas environment of the granary.

[0040] like Figure 1 and Fig.10 As shown, the detector chassis 11 includes a gas detection component 16, the detection end of the gas detection component 16 is connected to an active suction pump 15, the air inlet end of the active suction pump 15 is connected to a junction box 12, a plurality of solenoid valves 13 are provided at the air inlet end of the junction box 12, and a main air inlet pipe 14 is connected to each of the plurality of solenoid valves 13. The gas detection component 16, the active suction pump 15 and the solenoid valves 13 are all controlled by the intelligent system of the detector chassis 11, and the end of the main air inlet pipe 14 away from the detector chassis 11 is distributed at different positions of the granary according to actual needs.

[0041] The gas detection element 16 integrates a variety of gas sensors, including hydrogen sulfide sensors, carbon dioxide sensors, methane sensors, ammonia sensors and carbon monoxide sensors, etc., and is equipped with a sensor calibration system to ensure the measurement accuracy and stability of the sensors. In addition, the system of the detector chassis 11 is composed of a data processing and control unit composed of a microprocessor and an algorithm module. The microprocessor is used to collect and process sensor signals and perform data analysis and judgment; the algorithm module contains temperature and humidity compensation algorithms and gas concentration calculation models to improve detection accuracy. The detector chassis 11 system is also equipped with a communication and alarm unit, including a wired or wireless communication module, supporting RS485, WIFI, GPRS and other communication methods to achieve data transmission and remote monitoring, as well as an alarm device. When the concentration of harmful gases is detected to be excessive, an audible and visual alarm is issued in time;

[0042] In the gas detection stage, the gas sample enters the gas detection element 16, and each gas sensor detects the corresponding gas. The sensor converts the gas concentration signal into an electrical signal and transmits it to the data processing unit; then, in the data processing stage, the microprocessor receives the sensor signal, filters, amplifies and digitizes it, and applies a compensation algorithm to correct the measurement error caused by environmental factors such as temperature and humidity; then, in the result display and storage stage, the processed gas concentration value is displayed on the screen in real time for the staff to view, and the data is stored in the built-in memory at the same time, which can be used for later analysis and traceability; finally, in the communication and alarm stage, the data is sent to the monitoring center or the host computer through the communication module to realize remote monitoring; when the concentration of a certain gas exceeds the set threshold, the alarm device is activated, an audible and visual alarm is issued, and relevant personnel can be notified by SMS, email, etc.

[0043] When the detector chassis 11 is powered on and started, its built-in intelligent system will first perform initialization operations to check the working status of all components, including the gas detection element 16, the active suction pump 15, the solenoid valve 13, etc., to ensure that they are all in normal and operable conditions. The intelligent system will also determine the opening sequence and time interval of each solenoid valve 13 according to the preset sampling strategy or user-defined settings;

[0044] When a certain solenoid valve 13 is opened, the active suction pump 15 starts to work, generating negative pressure, and actively sucks the gas in the granary into the detector chassis 11 through the junction box 12 and the opened solenoid valve 13. This process ensures the accurate collection of gas samples and avoids interference from the external environment.

[0045] like Figure 3As shown, the external fixed-point sampling and suction mechanism 2 also includes a mounting box 21, on which a mounting member 29 is fixedly provided, and the mounting box 21 is fixed at different positions of the ceiling of the granary through the mounting member 29, and a turntable 22 is rotatably provided inside the mounting box 21, on which a winding belt 27 is provided, and a limiting cylinder 23 is fixedly provided below the turntable 22, and the bottom end of the limiting cylinder 23 is fixedly connected to the top end of the sampling outer tube 24.

[0046] An auxiliary control mechanism 4 is provided at one end of the reel 27 away from the mounting box 21, and the auxiliary control mechanism 4 includes an auxiliary control box 41, and the auxiliary control box 41 is installed on the wall near the granary door, a slide plate 42 is slidably provided inside the auxiliary control box 41, a binding rope part 44 that runs through the auxiliary control box 41 is fixedly provided on one side of the slide plate 42, a pull rope 43 is fixedly provided on the side of the slide plate 42 away from the binding rope part 44, and the binding rope part 44 is connected to the reel 27, and the pull rope 43 is connected to the inner wall of the granary door.

[0047] The granary door is closed and the pull rope 43 is pulled, and the slide plate 42 is pulled to slide in the auxiliary control box 41 by the pull rope 43, and each set of the reel 27 of the external fixed-point collection and suction mechanism 2 is connected to the rope binding member 44;

[0048] Before the granary door is closed, the sampling outer tube 24 of the external fixed-point sampling and suction mechanism 2 is usually retracted and does not directly contact the grain inside the granary. This is achieved by the turntable 22 and the winding belt 27 in the installation box 21. The slide plate 42 of the auxiliary control mechanism 4 is in a certain initial position in the auxiliary control box 41, and the pull rope 43 is in a relaxed state.

[0049] When the granary door begins to close, a certain component on the door will pull the drawstring 43, and the pulling force of the drawstring 43 acts on the slide plate 42, causing it to slide in the auxiliary control box 41. Since a rope binding member 44 is fixed to one side of the slide plate 42, the sliding of the slide plate 42 will drive the rope binding member 44 to move together, and the movement of the rope binding member 44 is transmitted to the turntable 22 through the winding belt 27, and the turntable 22 begins to rotate. Since the turntable 22 is connected to the top of the sampling outer tube 24 through the limit cylinder 23, the rotation of the turntable 22 will drive the sampling outer tube 24 to rotate together. The rotation angle of the sampling outer tube 24 is designed to be ninety degrees. In this way, when the granary door is completely closed, the sampling outer tube 24 also rotates to a position perpendicular to the inside of the granary, ready for gas sampling;

[0050] When the granary door needs to be opened, the components on the door will release the tension of the pull rope 43. At this time, under the gravity of the sampling outer tube 24, the slide plate 42 and the rope binding member 44 return to their initial positions. The movement of the rope binding member 44 drives the sampling outer tube 24 to rotate ninety degrees through the winding belt 27 and the turntable 22 again, and returns to the retracted state, so that the granary door can be opened smoothly without hindrance.

[0051] This design realizes the automatic lowering and folding of the sampling outer tube 24 through the mechanical linkage between the closing action of the granary door and the auxiliary control mechanism 4 and the external fixed-point sampling and suction mechanism 2, thereby simplifying the operation process and improving work efficiency.

[0052] like Figure 5 , Figure 6 and Figure 7 As shown, the driving member includes a mixing box 33, a piston 36 is slidably provided inside the mixing box 33, a guide column 37 is passed through the center position of the piston 36, an elastic band 38 and a pull belt 39 are fixedly provided on the side of the piston 36 away from the air outlet end of the mixing box 33, and a plurality of elastic bands 38 are provided, and the ends of the plurality of elastic bands 38 away from the piston 36 are fixedly connected to the guide column 37, and the air outlet end of the mixing box 33 is connected to the main air inlet pipe 14.

[0053] The upper and lower walls of the gas mixing box 33 are respectively provided with a through pipe 1 34 and a through pipe 2 35 . The air inlet ends of the through pipe 1 34 and the through pipe 2 35 are interconnected and connected to the air outlet end of the sampling inner tube 31 . The air outlet end of the through pipe 1 34 is located on the left side of the air outlet end of the through pipe 2 35 .

[0054] A driving cylinder 301 is fixedly provided at one end of the pull belt 39 away from the mixing box 33, a threaded bar 303 is fixedly provided on the inner wall of the driving cylinder 301, a driving disk 302 is rotatably provided inside the driving cylinder 301, a threaded groove 304 is provided on the outer wall of the driving disk 302, the threaded groove 304 is engaged with the threaded bar 303, and the driving disk 302 is fixedly connected to the top end of the sampling inner tube 31.

[0055] When the active suction pump 15 starts to work, it generates a strong suction force, which is not only used to suck gas from the granary, but also used to drive some mechanical structures inside the driving part;

[0056] Under the action of suction, air is first sucked in through the main air extraction port 32 and the main sampling port 26, and then enters the gas mixing box 33 through the through pipe 1 34 and the through pipe 2 35. At the same time, the piston 36 inside the gas mixing box 33 slides along the guide column 37 under the action of suction. This sliding process not only changes the gas pressure inside the gas mixing box 33, but also drives the rotation of the driving cylinder 301 through the connection of the pull belt 39.

[0057] The thread strip 303 on the inner wall of the driving cylinder 301 is engaged with the thread groove 304 on the outer wall of the driving disk 302. Therefore, when the driving cylinder 301 rotates, the driving disk 302 will also rotate accordingly. Since the driving disk 302 is fixedly connected to the top of the sampling inner tube 31, the sampling inner tube 31 will also rotate 180 degrees accordingly. This rotation process causes the position originally aligned with the main suction port 32 and the main sampling port 26 to be changed to be aligned with the auxiliary suction port 305 and the auxiliary sampling port 25, thereby preparing for the next step of gas sampling.

[0058] After the sampling inner tube 31 completes its rotation, the active suction pump 15 continues to work, and air begins to be sucked in through the auxiliary sampling port 25 and the auxiliary air extraction port 305, and enters the gas mixing box 33 again through the second through-tube 35 for subsequent gas sampling and detection;

[0059] The piston 36 is reset to the initial position under the tension of the elastic band 38. At the same time, the spring under the driving cylinder 301 will also help the driving cylinder 301 to reset to the initial position. When the driving cylinder 301 is reset, the sampling inner tube 31 will also reset to the initial position, preparing for the next round of gas sampling.

[0060] like Figure 8 and Fig. 9 As shown, a semi-cylindrical rotating block 306 is fixedly provided at the bottom end of the sampling inner tube 31, an air bag 307 is provided on one side of the rotating block 306, and the air bag 307 is fixed to the sampling outer tube 24. The air bag 307 is squeezed by the rotation of the rotating block 306 to discharge the gas.

[0061] The inner wall of the sampling inner tube 31 is fixedly provided with a blocking balloon 1 308 and a blocking balloon 2 309 . Both the blocking balloon 1 308 and the blocking balloon 2 309 are connected to the airbag 307 through a hose. The blocking balloon 1 308 is located above the blocking balloon 2 309 .

[0062] A sampling window 3001 is also provided on the outer wall of the sampling inner tube 31 on the same side of the main air extraction port 32. The height of the sampling window 3001 is located between the blocking balloon 1 308 and the blocking balloon 2 309. A sampling port 28 is provided on the outer wall of the sampling outer tube 24, and the sampling port 28 and the sampling window 3001 are located at the same height.

[0063] When the sampling inner tube 31 rotates for the first time, the airbag 307 is squeezed by rotating with the rotating block 306, so that air is filled into the blocking balloon 1 308 and the blocking balloon 2 309, thereby expanding the blocking balloon 1 308 and the blocking balloon 2 309, and blocking the pre-stored air inside the sampling inner tube 31. After that, the staff can manually extract the sample from the sampling window 3001 by opening the sampling port 28, so as to prevent the air inside the granary from being stirred by the staff entering;

[0064] When it is detected that the gas data at this branch position is different from the preset value, the electric-controlled valve 3002 connected to the airbag 307 prevents the gas in the blocking balloon 1 308 and the blocking balloon 2 309 from flowing back, and the blocking balloon 1 308 and the blocking balloon 2 309 are in an expanded state, and the electric-controlled valve 3002 is controlled by the system.

[0065] The above describes an embodiment of the present embodiment, but the present embodiment is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present embodiment, ordinary technicians in this field can also make many forms, all of which are within the protection of the present embodiment.

Claims

1. An inhalation type composite gas detector for a granary, characterized in that: It comprises a detector chassis (11) and a plurality of external fixed-point sampling and suction mechanisms (2), wherein the air inlet end of the detector chassis (11) is connected to the external fixed-point sampling and suction mechanisms (2); The external fixed-point sampling mechanism (2) comprises a sampling outer tube (24), a sampling inner tube (31) and a driving member, wherein the sampling outer tube (24) and the sampling inner tube (31) are linked via the driving member, and the sampling inner tube (31) is nested and movably arranged in the inner space of the sampling outer tube (24); The side wall of the sampling outer tube (24) is provided with a secondary sampling port (25) and a main sampling port (26), both of which are located in the same side wall area; the side wall of the sampling inner tube (31) is provided with a main air extraction port (32) and a secondary air extraction port (305), the main air extraction port (32) and the secondary air extraction port (305) are respectively located on different side walls of the sampling inner tube (31); the main air extraction port (32) is aligned with the main sampling port (26) in the vertical direction, and the secondary sampling port (25) is also aligned with the secondary air extraction port (305) in the vertical direction; Through the control of the driving member, the sampling inner tube (31) rotates around its axis, and then the main air suction port (32) and the auxiliary air suction port (305) are alternately aligned with the auxiliary sampling port (25) and the main sampling port (26) respectively, so as to suck in gas samples from different heights of the granary.

2. The suction type composite gas detector for granary according to claim 1, characterized in that: The detector chassis (11) comprises a gas detection element (16); a detection end of the gas detection element (16) is connected to an active suction pump (15); an air intake end of the active suction pump (15) is connected to a junction box (12); a plurality of solenoid valves (13) are provided at the air intake end of the junction box (12); and a main air intake pipe (14) is connected to each of the plurality of solenoid valves (13); the gas detection element (16), the active suction pump (15) and the solenoid valves (13) are all controlled by an intelligent system of the detector chassis (11); and an end of the main air intake pipe (14) away from the detector chassis (11) is distributed at different positions of the granary according to actual needs.

3. The suction type composite gas detector for granary according to claim 1, characterized in that: The external fixed-point sampling and suction mechanism (2) also includes a mounting box (21), on which a mounting member (29) is fixedly arranged, and the mounting box (21) is fixed to different positions of the ceiling of the granary through the mounting member (29), a turntable (22) is rotatably arranged inside the mounting box (21), a winding belt (27) is arranged on the turntable (22), and a limiting cylinder (23) is fixedly arranged below the turntable (22), and the bottom end of the limiting cylinder (23) is fixedly connected to the top end of the sampling outer tube (24).

4. The suction type composite gas detector for granary according to claim 3, characterized in that: An auxiliary control mechanism (4) is arranged at one end of the reel (27) away from the installation box (21), and the auxiliary control mechanism (4) includes an auxiliary control box (41), and the auxiliary control box (41) is installed on a wall near the granary door, and a slide plate (42) is slidably arranged inside the auxiliary control box (41), and a binding rope (44) that runs through the auxiliary control box (41) is fixedly arranged on one side of the slide plate (42), and a pull rope (43) is fixedly arranged on the side of the slide plate (42) away from the binding rope (44), and the binding rope (44) is connected to the reel (27), and the pull rope (43) is connected to the inner wall of the granary door.

5. The suction type composite gas detector for granary according to claim 2, characterized in that: The driving member comprises a gas mixing box (33), a piston (36) is slidably arranged inside the gas mixing box (33), a guide column (37) is penetrated at the center of the circle of the piston (36), an elastic band (38) and a drawstring (39) are fixedly arranged on the side of the piston (36) away from the gas outlet end of the gas mixing box (33), and a plurality of elastic bands (38) are arranged, and the ends of the plurality of elastic bands (38) away from the piston (36) are fixedly connected to the guide column (37), and the gas outlet end of the gas mixing box (33) is connected to the main air inlet pipe (14).

6. The suction type composite gas detector for granary according to claim 5, characterized in that: The upper and lower walls of the gas mixing box (33) are respectively provided with a through pipe 1 (34) and a through pipe 2 (35); the air inlet ends of the through pipe 1 (34) and the through pipe 2 (35) are interconnected and connected to the air outlet end of the sampling inner tube (31); the air outlet end of the through pipe 1 (34) is located on the left side of the air outlet end of the through pipe 2 (35).

7. The suction type composite gas detector for granary according to claim 5, characterized in that: A driving cylinder (301) is fixedly provided at one end of the pull belt (39) away from the mixing box (33), a threaded strip (303) is fixedly provided on the inner wall of the driving cylinder (301), a driving disk (302) is rotatably provided inside the driving cylinder (301), a threaded groove (304) is provided on the outer wall of the driving disk (302), the threaded groove (304) is engaged with the threaded strip (303), and the driving disk (302) is fixedly connected to the top end of the sampling inner tube (31).

8. The suction type composite gas detector for granary according to claim 1, characterized in that: A semi-cylindrical rotating block (306) is fixedly provided at the bottom end of the sampling inner tube (31), an air bag (307) is provided on one side of the rotating block (306), and the air bag (307) is fixed to the sampling outer tube (24). The rotating block (306) is rotated to squeeze the air bag (307) so that the gas is discharged.

9. The suction type composite gas detector for granary according to claim 8, characterized in that: The inner wall of the sampling inner tube (31) is fixedly provided with a blocking balloon 1 (308) and a blocking balloon 2 (309). Both the blocking balloon 1 (308) and the blocking balloon 2 (309) are connected to the airbag (307) through a hose, and the blocking balloon 1 (308) is located above the blocking balloon 2 (309).

10. The suction type composite gas detector for granary according to claim 9, characterized in that: The outer wall of the sampling inner tube (31) on the same side of the main air extraction port (32) is also provided with a sampling window (3001), and the height of the sampling window (3001) is located between the blocking balloon 1 (308) and the blocking balloon 2 (309). The outer wall of the sampling outer tube (24) is provided with a sampling port (28), and the sampling port (28) and the sampling window (3001) are located at the same height.

Images