Water transparency measuring device based on optical sensing technology

Abstract

The invention belongs to the technical field of water transparency measurement, and particularly relates to a water transparency measuring device based on an optical sensing technology, which comprises a saikowski disc, a first connecting block is fixedly connected to the center of the top of the saikowski disc, and a first connecting ball is rotatably mounted at the top of the first connecting block; the top of the first connecting ball is fixedly connected with a measuring rope, the end, away from the saybolt disc, of the measuring rope is connected with a handheld machine, and the bottom of the saybolt disc is provided with a conical first balancing weight. Dual detection of water transparency can be achieved through the pressure sensor and the light intensity sensor, compared with an existing manual measurement mode, errors in the manual detection process are reduced, meanwhile, the horizontal adjustment function of a second balancing weight and a third connecting ball on the light intensity sensor is matched, the measurement precision is improved, and the measurement accuracy is improved. Meanwhile, the convenience during detection is also improved, and the automation of water transparency detection is realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of water transparency measurement, and particularly relates to a water transparency measurement device based on optical sensing technology. Background Technique

[0002] Water transparency refers to the depth to which water can allow light to pass through. Pure water is colorless and transparent. When water contains substances such as sediment, microorganisms, suspended solids, and organic matter, it will become turbid, and the transparency of the water will decrease. The decrease in water transparency not only affects the sensory properties but also affects the life of aquatic organisms. Therefore, water transparency is also an indicator reflecting the water quality status.

[0003] Generally, the device used to measure water transparency is a Secchi disk (black and white disk). A measuring rope is connected to the center of the existing Secchi disk. During measurement, the Secchi disk is immersed in the water until the black and white boundary on the Secchi disk can no longer be seen. At this time, the length of the rope below the water surface is the transparency of the water body. Due to its relatively simple measurement method, it is commonly used to measure the transparency or light transmittance of surface water and is widely used in environmental monitoring, water quality assessment, and aquaculture production.

[0004] However, in the actual operation process, due to the overly simple structure of the Secchi disk, there are at least six aspects of errors or inconveniences during detection: First, the Secchi disk immersed in water drifts and tilts under the action of water flow, resulting in errors in determining the transparency critical value; second, the telescoping and curling of the rope will cause reading errors; third, the position, eyesight, and observation angle of the measurer will also affect the measurement results; fourth, the intensity of external light will affect the measurement results; fifth, when the measurer is far from the water surface, such as on a bridge or a boat, the reading of the Secchi disk measurement will be very inconvenient and the measurement error will be large; sixth, it relies on manual reading and cannot achieve automated measurement.

[0005] Therefore, it is very necessary to invent a water transparency measurement device based on optical sensing technology to solve the above problems. Summary of the Invention

[0006] In view of the above problems, the present invention provides a water transparency measurement device based on optical sensing technology to solve the problems raised in the above background technique.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A water transparency measuring device based on optical sensing technology, including a Secchi disk. A first connecting block is fixedly connected to the center of the top of the Secchi disk. A first connecting ball is rotatably installed on the top of the first connecting block. A measuring rope is fixedly connected to the top of the first connecting ball. One end of the measuring rope away from the Secchi disk is connected to a handheld device. A conical first counterweight is arranged at the bottom of the Secchi disk, and the gravity of the first counterweight is greater than that of the Secchi disk. A second connecting block is fixedly connected to the center of the top of the first counterweight. A second connecting ball is installed on the top of the second connecting block. The second connecting ball is fixedly connected to the center of the bottom of the Secchi disk. Two grooves are symmetrically opened on both sides of the conical surface of the first counterweight. An optical intensity measuring component is arranged in one of the grooves. A pressure sensor is installed at the bottom of the first counterweight. Data cables are connected between the pressure sensor and the optical intensity measuring component and the handheld device respectively.

[0009] Further, the optical intensity measuring component includes a mounting shaft. A third connecting ball is fixedly sleeved on the mounting shaft. The third connecting ball is rotatably installed on the top wall of the groove. The top of the mounting shaft is located above the top of the first counterweight. A through hole is penetrated through the top of the Secchi disk. The top end of the mounting shaft is located in the through hole. An optical intensity sensor is installed on the top of the mounting shaft. The top of the optical intensity sensor is flush with the top surface of the Secchi disk. The optical intensity sensor is connected to the handheld device through a data cable. A conical second counterweight is fixedly connected to the bottom end of the mounting shaft, and the gravity of the second counterweight is greater than that of the optical intensity sensor.

[0010] Further, a floating ring is fixedly connected to the periphery of the Secchi disk, and the buoyancy generated by the floating ring is between the gravity of the Secchi disk and the gravity of the first counterweight.

[0011] Further, the handheld device is internally provided with a PLC programmable logic controller, a battery and a GPS module, and a display screen and keys are installed on the handheld device.

[0012] Further, a plurality of cutting edges are evenly distributed in a circular shape at the bottom edge of the Secchi disk, and a plurality of cutting edges are all located on the diameter of the Secchi disk. One end of the cutting edge close to the center of the Secchi disk is fixedly connected to a slider. The slider is slidably installed on the bottom of the Secchi disk. A limiting block is fixedly connected to the bottom of the slider. The bottoms of a plurality of limiting blocks are provided with the same adjusting ring, and there is a gap between the bottom of the adjusting ring and the top of the first counterweight. The inner edge of the adjusting ring protrudes upward, and the upward protruding part of the inner edge of the adjusting ring is rotatably connected to the bottom of the Secchi disk. A plurality of inclined strip-shaped limiting holes are penetrated through the adjusting ring. A plurality of limiting blocks are slidably installed in a one-to-one correspondence in a plurality of strip-shaped limiting holes.

[0013] Further, the length of the cutting blade is less than the projection length of the strip-shaped limiting hole in the direction perpendicular to the diameter of the Secchi disk, and when the limiting hole is located at one end of the strip-shaped limiting hole far from the center of the Secchi disk, the cutting blade can extend from the bottom edge position of the Secchi disk.

[0014] Further, a plurality of snap rings for connecting the data cable and the measuring rope together are provided between the data cable and the measuring rope, and the plurality of snap rings are evenly distributed.

[0015] Further, a mounting shaft, a third connecting ball and a second counterweight are installed in the same way in the other groove. The mounting shafts, the third connecting balls and the second counterweights in the two grooves are all symmetrical about the axis of the first counterweight, and a through hole is also provided at the position of the top of the Secchi disk opposite to the current mounting shaft.

[0016] Further, a plurality of U-shaped protective rods woven crosswise are arranged around the pressure sensor, and the U-shaped protective rods are fixedly connected to the bottom of the first counterweight.

[0017] Technical effects and advantages of the present invention:

[0018] 1. The present invention can realize double detection of water transparency through the pressure sensor and the light intensity sensor. Compared with the existing manual measurement method, it reduces the error in the manual detection process. At the same time, with the horizontal adjustment function of the second counterweight and the third connecting ball for the light intensity sensor, it improves the measurement accuracy and also improves the convenience during detection, realizing the automation of water transparency detection;

[0019] 2. The present invention is provided with a floating ring. After the Secchi disk is put into the water, the floating ring can generate buoyancy on the Secchi disk, so that the Secchi disk can better maintain a horizontal state under the buoyancy of the floating ring. Furthermore, when the tester observes the Secchi disk from the top of the Secchi disk, the Secchi disk can also be well perpendicular to the tester's observation line of sight, improving the accuracy of the Secchi disk for detecting water transparency;

[0020] 3. The present invention is provided with a cutting blade. Before detecting the water body, by rotating the adjusting ring, the cutting blade can extend from the bottom edge position of the Secchi disk under the push of the strip-shaped limiting hole on the limiting block. Thus, when there are waterweeds around the Secchi disk during the process of the Secchi disk entering or exiting the water body, the cutting blade can cut the waterweeds, thereby preventing the Secchi disk from being entangled by the waterweeds. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic diagram of the overall structure of the present invention;

[0022] Figure 2It is a three-dimensional schematic diagram of all structures in the present invention except for the measuring rope and the handheld device;

[0023] Figure 3 In the present invention Figure 2 The front view;

[0024] Figure 4 It is a three-dimensional schematic diagram of the first counterweight, the second connecting block, the pressure sensor, the U-shaped protective rod, and the light intensity measuring component in the present invention;

[0025] Figure 5 It is a three-dimensional schematic of the adjusting ring in the present invention;

[0026] Figure 6 It is a three-dimensional schematic diagram of structures such as the Secchi disk, the second connecting ball, the floating ring, and the cutting edge in the present invention;

[0027] Figure 7 It is a three-dimensional schematic diagram of the pressure sensor, the data cable, and the light intensity sensor in the present invention.

[0028] In the figure: 1. Secchi disk; 2. First connecting block; 3. First connecting ball; 4. Measuring rope; 5. Handheld device; 6. First counterweight; 7. Second connecting block; 8. Second connecting ball; 9. Light intensity measuring component; 91. Mounting shaft; 92. Third connecting ball; 93. Through hole; 94. Light intensity sensor; 95. Second counterweight; 10. Pressure sensor; 11. Data cable; 12. Floating ring; 13. Cutting edge; 14. Slide block; 15. Limit block; 16. Adjusting ring; 17. Strip-shaped limit hole; 18. Snap ring; 19. U-shaped protective rod. Specific embodiments

[0029] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments.

[0030] The present invention provides as Figures 1 to 7A water transparency measuring device based on optical sensing technology is shown, including a Secchi disk 1. At the center of the top of the Secchi disk 1, a first connecting block 2 is fixedly connected. At the top of the first connecting block 2, a first connecting ball 3 is rotatably installed. At the top of the first connecting ball 3, a measuring rope 4 is fixedly connected. One end of the measuring rope 4 away from the Secchi disk 1 is connected to a handheld device 5. At the bottom of the Secchi disk 1, a conical first counterweight 6 is provided, and the gravity of the first counterweight 6 is greater than the gravity of the Secchi disk 1. At the center of the top of the first counterweight 6, a second connecting block 7 is fixedly connected. At the top of the second connecting block 7, a second connecting ball 8 is installed. The second connecting ball 8 is fixedly connected to the center of the bottom of the Secchi disk 1. On both sides of the conical surface of the first counterweight 6, two grooves are symmetrically opened. In one of the grooves, a light intensity measuring component 9 is provided. At the bottom of the first counterweight 6, a pressure sensor 10 is installed. Data cables 11 are connected between the pressure sensor 10 and the light intensity measuring component 9 and the handheld device 5. The handheld device 5 is internally provided with a PLC programmable logic controller, a battery, and a GPS module. And a display screen and keys are installed on the handheld device, and the geographical coordinate information of the measurement site can be synchronously recorded;

[0031] The light intensity measuring component 9 includes a mounting shaft 91. A third connecting ball 92 is fixedly sleeved on the mounting shaft 91. The third connecting ball 92 is rotatably installed on the top wall of the groove. And the top of the mounting shaft 91 is located at the top of the first counterweight 6. A through hole 93 is penetrated through the top of the Secchi disk 1. The top end of the mounting shaft 91 is located in the through hole 93. A light intensity sensor 94 is installed at the top of the mounting shaft 91. The top of the light intensity sensor 94 is flush with the top surface of the Secchi disk 1. And the light intensity sensor 94 is connected to the handheld device 5 through a data cable 11. A conical second counterweight 95 is fixedly connected to the bottom end of the mounting shaft 91. And the gravity of the second counterweight 95 is greater than the gravity of the light intensity sensor 94;

[0032] I. Calibration: Before using the present invention to detect the transparency of water, it is necessary to calibrate the light intensity sensor 94 first. The specific calibration process is as follows:

[0033] Under normal light, according to the method of measuring the transparency of the regular Secchi disk, lower the Secchi disk in this device from the water surface L0 to the position L1 where the black and white dividing line of the Secchi disk 1 cannot be visually distinguished. Record the light intensities at the two water depths of L0 and L1 respectively, and calculate the ratio of the latter to the former light intensity, that is, the attenuation rate KK < 1;

[0034] II. Detection: When using the present invention for detection, the specific detection process is as follows:

[0035] Arrive at the measurement point, place the Secchi disk flat on the water surface and measure the surface light intensity. When the Secchi disk 1 is placed on the water surface, the Secchi disk 1 can adaptively deflect with the first connecting ball 3 as the center under the pulling of the first counterweight 6, so that the Secchi disk 1 can float horizontally on the water surface, avoiding measurement errors caused by the bending and curling of the measuring rope 4 resulting in the inclination of the Secchi disk 1;

[0036] Subsequently, release the measuring rope 4 to slowly sink the Secchi disk. During the downward movement of the Secchi disk 1, the light intensity sensor 94 can deflect with the third connecting ball 92 as the center under the pulling of the second counterweight 95 on the mounting shaft 91, so that the light intensity sensor 94 always remains vertical. Since the water surface can remain horizontal under the action of the earth's gravity, the light intensity sensor 94 that always remains vertical can always be perpendicular to the horizontal, thus avoiding measurement errors caused by the inclination of the light intensity sensor 94 and improving the measurement accuracy. In addition, during the slow sinking of the Secchi disk, the light intensity sensor 94 can continuously record the water depth value and the synchronous light intensity. When the received light intensity is exactly K times the surface light intensity, the water depth here is the transparency of the water body. Subsequently, the handheld device 5 can send a signal and record the final data on the display screen, and the measurement is completed;

[0037] Among them, the pressure sensor 10 of this device is used for measuring the water depth. It can continuously transmit the water pressure signal back to the handheld device 5 during the sinking process of the Secchi disk in the water and convert it into water depth information. Subsequently, subtracting the distance between the bottom of the Secchi disk 1 and the pressure sensor 10 from the obtained water depth information is the measured actual water depth;

[0038] The light intensity sensor 94 of this device is used for measuring the light intensity in the water. The attenuation of light in water follows the exponential attenuation law. The light intensity on the water surface is the largest and gradually decreases with the increase of water depth. The attenuation coefficient of light in water is negatively correlated with its transparency. The greater the transparency, the smaller the attenuation coefficient;

[0039] The present invention can realize the dual detection of the water body transparency through the pressure sensor 10 and the light intensity sensor 94. Compared with the existing manual measurement method, it reduces the errors in the manual detection process, improves the measurement accuracy, and at the same time improves the convenience during detection, realizing the automation of the water body transparency detection.

[0040] As Figures 1 to 3 shown, a floating ring 12 is fixedly connected to the periphery of the Secchi disk 1, and the buoyancy generated by the floating ring 12 is between the gravity of the Secchi disk 1 and the gravity of the first counterweight 6;

[0041] After the Secchi disk 1 is placed in the water body, the floating ring 12 can generate buoyancy on the Secchi disk 1, so that the Secchi disk 1 can better maintain a horizontal state under the buoyancy of the floating ring 12. Furthermore, it is ensured that when the tester observes the Secchi disk 1 from the top of the Secchi disk 1, the Secchi disk 1 can also be perpendicular to the tester's observation line of sight, improving the accuracy of the Secchi disk 1 for detecting the transparency of the water body.

[0042] As Figures 1 to 6 shown, a plurality of cutting blades 13 are evenly distributed in a circular shape along the bottom edge of the Secchi disk 1, and the plurality of cutting blades 13 are all located on the diameter of the Secchi disk 1. One end of the cutting blade 13 close to the center of the Secchi disk 1 is fixedly connected to a slider 14. The slider 14 is slidably installed on the bottom of the Secchi disk 1. The bottom of the slider 14 is fixedly connected to a limiting block 15. The bottoms of the plurality of limiting blocks 15 are provided with a same adjusting ring 16, and there is a gap between the bottom of the adjusting ring 16 and the top of the first counterweight 6. The inner edge of the adjusting ring 16 bulges upward, and the upwardly bulging part of the inner edge of the adjusting ring 16 is rotatably connected to the bottom of the Secchi disk 1. A plurality of inclined strip-shaped limiting holes 17 are formed through the adjusting ring 16. The plurality of limiting blocks 15 are slidably installed in the plurality of strip-shaped limiting holes 17 one by one. The length of the cutting blade 13 is less than the projection length of the strip-shaped limiting hole 17 in the direction perpendicular to the diameter of the Secchi disk 1. When the limiting hole is located at the end of the strip-shaped limiting hole 17 far from the center of the Secchi disk 1, the cutting blade 13 can extend out from the bottom edge position of the Secchi disk 1;

[0043] By providing the cutting blade 13, before detecting the water body, the adjusting ring 16 can be rotated. As the adjusting ring 16 rotates, the adjusting ring 16 can push the limiting block 15 through the hole wall of the strip-shaped limiting hole 17, so that the limiting block 15 drives the slider 14 to move along the strip-shaped limiting hole 17 in a direction away from the center of the Secchi disk 1. As the slider 14 moves, the cutting blade 13 can be driven by the slider 14 to extend out from the bottom edge position of the Secchi disk 1. Thus, when the Secchi disk 1 enters or exits the water body, when there are waterweeds around the Secchi disk 1, the cutting blade 13 can cut the waterweeds, thereby preventing the Secchi disk 1 from being entangled by the waterweeds. After the detection is completed, as the Secchi disk 1 is taken out of the water body, the adjusting ring 16 can be rotated in the reverse direction, so that the cutting blade 13 can be retracted into the gap between the Secchi disk 1 and the first counterweight 6, thereby preventing the cutting blade 13 from accidentally injuring the tester.

[0044] As Figure 1 shown, a plurality of snap rings 18 for connecting the data cable 11 and the measuring rope 4 are provided between the data cable 11 and the measuring rope 4, and the plurality of snap rings 18 are evenly distributed;

[0045] By providing a snap ring 18, the data cable 11 can be bound to the measuring rope 4, thereby preventing the data cable 11 from being entangled with the Secchi disk 1 or other structures during the measurement process.

[0046] As Figures 1 to 4 shown, an installation shaft 91, a third connecting ball 92, and a second counterweight 95 are installed in the same manner in the other groove. The installation shafts 91, the third connecting balls 92, and the second counterweights 95 in the two grooves are all symmetric about the axis of the first counterweight 6, and a through hole 93 is also provided through the position of the top of the Secchi disk 1 directly opposite to the current installation shaft 91;

[0047] By symmetrically providing the installation shafts 91, the third connecting balls 92, and the second counterweights 95 in the two grooves, the balance of the pulling force of the first counterweight 6 on the Secchi disk can be maintained during the measurement of the water transparency by the Secchi disk 1, so that the Secchi disk 1 can better maintain balance.

[0048] As Figures 1 to 4 shown, a plurality of U-shaped protective rods 19 woven together crosswise are provided around the pressure sensor 10, and the U-shaped protective rods 19 are fixedly connected to the bottom of the first counterweight 6;

[0049] By providing the U-shaped protective rods 19, when the present invention is placed on the ground or moves downward in water, the U-shaped protective rods 19 can protect the pressure sensor 10, thereby preventing the pressure sensor 10 from being damaged due to collision.

[0050] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it.

Claims

1. A water transparency measuring device based on optical sensing technology, comprising a Secchi disk (1), characterized in that: A first connection block (2) is fixedly connected at the center of the top of the Secchi disk (1); a first connection ball (3) is rotatably mounted on the top of the first connection block (2); a measuring rope (4) is fixedly connected to the top of the first connection ball (3); a handheld device (5) is connected to the end of the measuring rope (4) away from the Secchi disk (1); a conical first counterweight block (6) is arranged at the bottom of the Secchi disk (1); and the gravity of the first counterweight block (6) is greater than the gravity of the Secchi disk (1); and a first counterweight block (6) is fixedly connected at the center of the top of the first counterweight block (6). A second connecting block (7) is provided, a second connecting ball (8) is installed on the top of the second connecting block (7), and the second connecting ball (8) is fixedly connected to the bottom center of the Secchi disk (1). Two grooves are symmetrically provided on both sides of the conical surface of the first counterweight block (6), and a light intensity measurement component (9) is arranged in one of the grooves. A pressure sensor (10) is installed at the bottom of the first counterweight block (6), and a data cable (11) is connected between the pressure sensor (10) and the light intensity measurement component (9) and the handheld device (5).

2. The water transparency measuring device based on optical sensing technology according to claim 1 is characterized in that: The light intensity measurement component (9) comprises a mounting shaft (91), a third connecting ball (92) is fixedly sleeved on the mounting shaft (91), the third connecting ball (92) is rotatably mounted on the top wall of the groove, and the top of the mounting shaft (91) is located at the top of the first counterweight (6), a through hole (93) is opened through the top of the Secchi disk (1), the top of the mounting shaft (91) is located in the through hole (93), a light intensity sensor (94) is installed on the top of the mounting shaft (91), the top of the light intensity sensor (94) is flush with the top surface of the Secchi disk (1), and the light intensity sensor (94) is connected to the handheld device (5) through a data cable (11), and the bottom end of the mounting shaft (91) is fixedly connected to a conical second counterweight (95), and the gravity of the second counterweight (95) is greater than the gravity of the light intensity sensor (94).

3. The water transparency measuring device based on optical sensing technology according to claim 2 is characterized in that: A floating ring (12) is fixedly connected to the periphery of the Secchi disk (1), and the buoyancy generated by the floating ring (12) is between the gravity of the Secchi disk (1) and the gravity of the first counterweight block (6).

4. The water transparency measuring device based on optical sensing technology according to claim 1 is characterized in that: The handheld device (5) has a built-in PLC programmable logic controller, a battery and a GPS module, and a display screen and buttons are installed on the handheld device.

5. The water transparency measuring device based on optical sensing technology according to claim 3 is characterized in that: The bottom edge of the Secchi disk (1) is evenly distributed with a plurality of cutting blades (13) in an annular shape, and the plurality of cutting blades (13) are all located on the diameter of the Secchi disk (1); one end of the cutting blade (13) close to the center of the Secchi disk (1) is fixedly connected with a slider (14); the slider (14) is slidably mounted on the bottom of the Secchi disk (1); the bottom of the slider (14) is fixedly connected with a limiting block (15); the bottoms of the plurality of limiting blocks (15) are provided with a same adjusting ring (16); a gap is provided between the bottom of the adjusting ring (16) and the top of the first counterweight (6); the inner edge of the adjusting ring (16) protrudes upwards, and the portion of the inner edge of the adjusting ring (16) protruding upwards is rotatably connected to the bottom of the Secchi disk (1); the adjusting ring (16) is provided with a plurality of inclined strip limiting holes (17); the plurality of limiting blocks (15) are slidably mounted in the plurality of strip limiting holes (17) in a one-to-one correspondence.

6. The water transparency measuring device based on optical sensing technology according to claim 5 is characterized in that: The length of the cutting blade (13) is smaller than the projected length of the strip-shaped limiting hole (17) perpendicular to the diameter direction of the Secchi disk (1), and when the limiting hole is located at the end of the strip-shaped limiting hole (17) away from the center of the Secchi disk (1), the cutting blade (13) can extend from the bottom edge of the Secchi disk (1).

7. The water transparency measuring device based on optical sensing technology according to claim 2 is characterized in that: A plurality of clasps (18) for connecting the data cable (11) and the measuring rope (4) are arranged between the data cable (11) and the measuring rope (4), and the plurality of clasps (18) are evenly distributed.

8. The water transparency measuring device based on optical sensing technology according to claim 2 is characterized in that: The other groove is provided with a mounting shaft (91), a third connecting ball (92) and a second counterweight (95) in the same manner. The mounting shafts (91), the third connecting ball (92) and the second counterweight (95) in the two grooves are symmetrical about the axis of the first counterweight (6), and a through hole (93) is also provided at a position on the top of the Secchi disk (1) directly opposite to the current mounting shaft (91).

9. The water transparency measuring device based on optical sensing technology according to claim 8 is characterized in that: A plurality of U-shaped protective rods (19) that are cross-woven together are arranged on the periphery of the pressure sensor (10), and the U-shaped protective rods (19) are fixedly connected to the bottom of the first counterweight (6).

Images