13 1 2 44
4
23 43 11 FIG. 2
WATER QUALITY DETECTION DEVICE FOR WATER POLLUTION CONTROL TECHNICAL FIELD The present disclosure relates to the field of environment protection technologies, in particular to a water quality detection device for water pollution control. BACKGROUND Water pollution control system planning refers to optimal planning for approaches to urban (or regional) water environment system engineering. Specifically, laws, regulations, and standards are taken as bases, environmental protection technology planning and regional economic development planning are taken as guidelines. The best comprehensive benefits of regional water pollution control systems are taken as targets. The best applicable control technologies are taken as strategies and measures. Occurrence and control of pollution sources, sewage discharge mechanisms, sewage treatment, and water quality are entirely considered, and a relationship between them and economic development, technological improvements and management strengthening is also overall considered. In this ways, investigation, monitoring, evaluation, prediction, simulation, and optimized decision are performed on the systems, so as to seek overall optimized schemes of short-term and long-term pollution control planning. The Water pollution control system planning includes high-quality water quality planning as well as multi-scheme simulation and optimization planning for water pollution control. The high-quality water quality planning includes minimum reduction quantity planning for discharge outlets, optimal treatment planning for discharge outlets, optimal uniform treatment planning, and optimal planning for regional sewage transportation and regional sewage treatment. The multi-scheme simulation and optimization planning for the water pollution control is regarded as a practical and effective planning method for the regional water pollution control systems. After sewage treatment is performed, the quality of sewage is necessary to detect before the sewage is discharged; and whether or not the sewage treatment reaches the standard is determined based on a detection result. After that, sewage discharge is controlled. An existing water quality detection device for water pollution control manually samples water bodies on site, needs to perform detection repeatedly, has low efficiency due to manual operation, and is time-consuming and labor-intensive. SUMMARY The objective of the present disclosure is to solve the above problems by providing a water quality detection device for water pollution control, which can achieve automated and low-cost sampling at multiple depths. The above objective of the present disclosure is fulfilled through the following technical solution: A water quality detection device for water pollution control includes a detection and sampling mechanism including sampling units, an interlocking unit, a lifting unit, and a driving unit, where the interlocking unit is connected to a plurality of sampling units and connects the lifting unit to the driving unit; the sampling units, the interlocking unit, the lifting unit, and the driving unit are arranged on a central shaft; and the interlocking unit together with the sampling units is driven to descend by the lifting unit, and opens and closes the sampling units one by one at the same time, so as to sample a water body at different depths. Preferably, the interlocking unit may include a base, a disk, first grooved wheels, and a second grooved wheel, where a through hole in clearance fit with the central shaft may be formed in the center of the disk; the disk partially may protrude to form an outward extension portion; a first shifting lever may be fixedly arranged on the top of the outward extension portion; a plurality of first grooved wheels may be uniformly arranged outside the disk in an annular array manner; first grooved wheel shafts may be fixedly arranged at centers of the first grooved wheels and have upper ends connected to the base through bearings; a through hole in clearance fit with the central shaft may be formed in the center of the base arranged above the disk; the second grooved wheel on the top of the disk may be fixedly connected to the disk and is concentric with the disk; a through hole also in clearance fit with the central shaft may be formed in the center of the second grooved wheel; and both the disc and the base may be in clearance fit with the central shaft, so that the interlocking unit may be slidably connected to the central shaft as a whole. Preferably, shifting grooves may be uniformly formed in an annular array manner in the first grooved wheels and the second grooved wheel; the number of the shifting grooves in the second grooved wheel may be the same as a total number of the first grooved wheels; in a case where each shifting groove in the second grooved wheel rotates once in cooperation with the driving unit, the disk may be driven to rotate by a certain angle; and in this way, the corresponding first grooved wheel may be shifted once. Preferably, the base may be connected to the disk through a connecting rod. Preferably, the lifting unit may include a stop block and a spacer sleeve, where the spacer sleeve may be fixedly arranged at the center of the bottom of the disk; a through hole in clearance with the central shaft may be formed in the center of the spacer sleeve; a plurality of steps having heights sequentially reduced may be uniformly arranged in an annular array manner on the spacer sleeve; and the stop block matched with the steps may be arranged on the central shaft. The spacer sleeve may rotate with rotation of the disk; when the stop block on the central shaft is matched with the highest step of the spacer sleeve, the disk and the interlocking unit may be highest; and when the stop block is matched with the next step by means of rotation of the spacer sleeve, the disk and the interlocking unit may drop by a height of one step due to gravity. In this way, after a circle of rotation of the disk, the interlocking unit may drop by a height of the plurality of steps, so that a step type drop may be achieved. Preferably, the stop block may have the same cross section as each step. Preferably, the driving unit may include a rocker arm, a second shifting lever, a motor, and a slide base, where the rocker arm may have one end provided with the second shifting lever at the bottom as well as the other end fixedly connected to an output shaft of the motor; and the slide base fixedly provided with the motor may be disposed around the central shaft and slidably connected to the central shaft. The motor as a power unit on an installation platform, namely the slide base, may drive the rocker arm to rotate, so as to drive the second grooved wheel to rotate by means of the second shifting lever; and in this way, the interlocking unit may be driven to rotate. Preferably, a longitudinal limit mechanism between the slide base and the central shaft may include a slideway and a slider, where the slideway may be formed in the central shaft along an axis of the central shaft; the slider matched with the slideway may be arranged in the slide base; and the slideway and the slider matched with the slideway may restrain rotation of the slide base without preventing the slide base from moving longitudinally. Preferably, each sampling unit may include a sampling tank and an open-close mechanism in the sampling tank, where the open-close mechanism may include an open-close shaft, an open-close baffle, and a sampling port; the open-close shaft may be arranged at the center of the sampling tank and have a top connected to the lower end of the corresponding first grooved wheel shaft through a connector; the open-close baffle may be fixedly arranged at the bottom of the open-close shaft; the sampling port may be formed in the bottom of the sampling tank; and a notch matched with the sampling port may be formed in the open-close baffle. The present disclosure has the following beneficial effects: 1) The water quality detection device can achieve automated sampling, is low in cost by adoption of a mechanical structure, and can be conveniently arranged at a water quality detection point, thus saving manpower and material resources; 2) The water quality detection device can automatically sectionally sample the water body at different depths and obtain various water samples, thus well reflecting the quality of water at the water quality detection point. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a top view of the present disclosure in embodiment 1; FIG. 2 is a structural diagram of an interlocking unit and a driving unit of the present disclosure in embodiment 1; FIG. 3 is a structural diagram of the interlocking unit of the present disclosure in embodiment 1; FIG. 4 is a structural diagram of sampling units of the present disclosure in embodiment 1;
FIG. 5 is a structural diagram of a disk of the interlocking unit of the present disclosure in embodiment 1; FIG. 6 is a schematic diagram of an internal structure of one sampling unit of the present disclosure in embodiment 1; FIG. 7 is another schematic diagram of the internal structure of the sampling unit of the present disclosure in embodiment 1; FIG. 8 is a structural diagram of a lifting unit of the present disclosure in embodiment 1; FIG. 9 is a structural diagram of a spacer sleeve of the present disclosure in embodiment 1. In the figure, 1. sampling unit; 2. interlocking unit, 3. lifting unit, 4. driving unit, 5. central shaft; 11. sampling tank, 12. open-close mechanism, 13. holder, 121. open-close shaft, 122. open-close baffle, 123. sampling port; 21. base, 22. disk, 23. first grooved wheel, 24. second grooved wheel, 25. first shifting lever; 31. stop block, 32. spacer sleeve, 321. step; 41. rocker arm, 42. second shifting lever, 43. motor, 44. slide base. DETAILED DESCRIPTION The present application is described in further detail below with reference to the accompanying drawings. It should be understood that the following specific implementations are only intended to further explain the present application, rather than to constitute a limitation on the protection scope of the present application. Those skilled in the art may make non-essential improvements and adjustments to the present application based on the above content. Embodiment 1: As shown in FIG. 1-9, a water quality detection device for water pollution control includes a detection and sampling mechanism including sampling units 1, an interlocking unit 2, a lifting unit 3, and a driving unit 4, where the interlocking unit 2 is connected to a plurality of sampling units 1 and connects the lifting unit 3 to the driving unit 4; the sampling units 1, the interlocking unit 2, the lifting unit 3, and the driving unit 4 are arranged on a central shaft 5; and the interlocking unit 2 together with the sampling units 1 is driven to descend by the lifting unit 3, and opens and closes the sampling units 1 one by one at the same time, so as to sample a water body at different depths. The interlocking unit 2 includes a base 21, a disk 22, first grooved wheels 23, and a second grooved wheel 24, where a through hole in clearance fit with the central shaft 5 is formed in the center of the disk 22; the disk 22 partially protrudes to form an outward extension portion; a first shifting lever 25 is fixedly arranged on the top of the outward extension portion; a plurality of first grooved wheels 23 are uniformly arranged outside the disk in an annular array manner 22; first grooved wheel shafts are fixedly arranged at centers of the first grooved wheels 23 and have upper ends connected to the base 21 through bearings; a through hole in clearance fit with the central shaft is formed in the center of the base 21 arranged above the disk 22; the second grooved wheel 24 on the top of the disk 22 is fixedly connected to the disk 22 and is concentric with the disk 22; a through hole also in clearance fit with the central shaft 5 is formed in the center of the second grooved wheel 24; and both the disc 22 and the base 21 are in clearance fit with the central shaft 5, so that the interlocking unit 2 is slidably connected to the central shaft 5 as a whole. Preferably, shifting grooves are uniformly formed in an annular array manner in the first grooved wheels 23 and the second grooved wheel 24; the number of the shifting grooves in the second grooved wheel 24 is the same as a total number of the first grooved wheels 23; in a case where each shifting groove in the second grooved wheel 24 rotates once in cooperation with the driving unit, the disk 22 will be driven to rotate by a certain angle; and in this way, the corresponding first grooved wheel 23 will be shifted once. Preferably, the base 21 is connected to the disk 22 through a connecting rod. The lifting unit 3 includes a stop block 31 and a spacer sleeve 32, where the spacer sleeve 32 is fixedly arranged at the center of the bottom of the disk 22; a through hole in clearance with the central shaft 5 is formed in the center of the spacer sleeve 32; a plurality of steps 321 having heights sequentially reduced are uniformly arranged in an annular array manner on the spacer sleeve 32; and the stop block 31 matched with the steps 321 is arranged on the central shaft 5. The spacer sleeve 32 can rotate with rotation of the disk 22; when the stop block 31 on the central shaft 5 is matched with the highest step 321 of the spacer sleeve 32, the disk 22 and the interlocking unit 2 are highest; and when the stop block 31 is matched with the next step 321 by means of rotation of the spacer sleeve 32, the disk 22 and the interlocking unit 2 drop by a height of one step 321 due to gravity. In this way, after a circle of rotation of the disk 22, the interlocking unit 2 drops by a height of the plurality of steps 321, so that a step 321 type drop is achieved. Preferably, the stop block 31 has the same cross section as each step 321. The driving unit 4 includes a rocker arm 41, a second shifting lever 42, a motor 43, and a slide base 44, where the rocker arm 41 has one end provided with the second shifting lever 42 at the bottom as well as the other end fixedly connected to an output shaft of the motor 43; and the slide base 44 fixedly provided with the motor 43 is disposed around the central shaft 5 and slidably connected to the central shaft 5. The motor 43 as a power unit on an installation platform, namely the slide base 44, drives the rocker arm 41 to rotate, so as to drive the second grooved wheel 24 to rotate by means of the second shifting lever 42; and in this way, the interlocking unit 2 is driven to rotate. Preferably, the slide base 44 is located below the base 21; and when descending, the base 21 of the interlocking unit 2 pushes the slide base 44 and the motor 43 to downwards move simultaneously, so that the second shifting lever 42 is prevented from disengaging from the second grooved wheel 24. Preferably, to avoid rotation, caused because a reaction force from the second grooved wheel 24 to the rocker arm 41 is transmitted to the motor 43, of the motor 43 and the slide base 44, a longitudinal limit mechanism is arranged between the slide base 44 and the central shaft 5; and the longitudinal limit mechanism includes a slideway formed in the central shaft 5 along an axis of the central shaft 5 as well as a slider, matched with the slideway, in the slide base 44, where the slideway and the slider matched with the slideway restrain rotation of the slide base 44 without preventing the slide base 44 from moving longitudinally. Each sampling unit 1 includes a sampling tank 11 and an open-close mechanism 12 in the sampling tank 11, where the open-close mechanism 12 includes an open-close shaft 121, an open-close baffle 122, and sampling ports 123; the open-close shaft 121 is arranged at the center of the sampling tank 11 and has a top connected to the lower end of the corresponding first grooved wheel shaft through a connector; the open-close baffle 122 is fixedly arranged at the bottom of the open-close shaft 121; the sampling ports 123 are formed in the bottom of the sampling tank 11; and notches matched with the sampling ports 123 are formed in the open-close baffle 122. Preferably, an assembly structure for the sampling tanks 11 particularly includes a holder 13, where the sampling tanks 11 are fixedly arranged in holes, matched with the sampling tanks 11, in the holder 13; and the holder 13 is connected, through a connecting rod, to the base 21 above the holder 13 and ascends and descends along with the interlocking unit 2. Preferably, the sampling tanks 11 are connected, through tubes, to a water pump above the sampling tanks 11, and the water pump is used to pump water samples in the sampling tanks 11. Necessarily, the motor 43 should be a controllable servo motor 43 and be connected to an upper computer and a power supply through an actuator to control an angle of rotation and a rotational speed. Necessarily, a waterproof shell should be arranged outside the motor 43 to isolate the motor 43; and in this way, the motor 43 can normally operate in the water body. The principle of the present disclosure is as follows: the central shaft 5 is fixed to serve as a support for the device; the rocker arm 41 of the driving unit can drive the second shifting lever 42 to rotate, so as to drive the second grooved wheel 24 to rotate; through transmission of the second grooved wheel 24, the disk 22 can rotate by the certain angle at intervals; in a case where the disk 22 rotates once, one first grooved wheel 23 outside the disk 22 rotates once along with the disk 22; and in a case where the first grooved wheel 23 rotates once, the corresponding sampling tank 11 is driven to open and close once for sampling. Meanwhile, in the case where the disk 22 rotates once, the spacer sleeve 32 at the bottom of the disk 22 is driven to rotate to the next step 321; and in this way, the sampling units 1 and the interlocking unit 2 will drop by a height of one step 321 as a whole; and These two synchronous processes will generate such a result: after sampling of one sampling tank 11, the sampling units 1 and the interlocking unit 2 simultaneously drop by a height of one step 321, and then the next sampling tank 11 sample the water body at the corresponding depth; after that, the sampling units 1 and the interlocking unit 2 once again drop by a height of one step 321; and in a similar way, the sampling tanks 11 respectively sample the water body at different depths. Embodiment 2: Particularly, in a case where a first shifting lever passes through one first grooved wheel 23 once, three shifting grooves in the first grooved wheel 23 will be driven to rotate by 1200; at this moment, each notch in the corresponding open-close baffle 122 corresponds to a central angle of ; and furthermore, three sampling ports 123 are uniformly formed in the annular array manner in each sampling tank 11, and each sampling port 123 corresponds to a central angle of 600; in a case where the first grooved wheel shaft of the first grooved wheel 23 rotates by 120, the corresponding open-close shaft 121 drives the open-close baffle 122 to rotate by 120, so that one notch passes through the corresponding sampling port 123 once; and in this way, the sampling port 123 is opened and closed once. Embodiment 3: Based on embodiment 1, the present disclosure provides a facility for returning the water quality detection device. Particularly, a hoisting mechanism is arranged on the installation platform above the device; the lifting mechanism is connected to the disk 22 of the interlocking unit 2, so as to drive the interlocking unit 2 to ascend as a whole; after the interlocking unit 2 ascends, the spacer sleeve 32 of the lifting unit 3 is separated from the stop block 31; and the motor 43 drives the spacer sleeve 32 and the interlocking unit 2 to return. The hoisting mechanism may be various linear actuators or hoisting facilities such as a hoisting machine. In a case where the hoisting mechanism is the hoisting machine, the disk 22 of the interlocking unit 2 is connected to one end of a wire rope on a hoisting drum of the hoisting machine. In a simple manner, the interlocking unit 2 can be manually driven by a pulling rope to be returned when a sample is taken away. Embodiment 4 Based on embodiment 1, the present disclosure provides a detection method implemented by using the water quality detection device. Particularly, water samples in the sampling tanks 11 are pumped by the water pump into all detection devices for detection. The above descriptions are merely several embodiments of the present disclosure. Although the description is specific and detailed, it should not be construed as a limitation to the patent scope of the present disclosure. It should be noted that those ordinarily skilled in the art can further make several variations and improvements without departing from the conception of the present disclosure. These all fall within the protection scope of the present disclosure.