High-precision turbidity sensor

Abstract

The utility model discloses a high-precision turbidity sensor. The high-precision turbidity sensor comprises a PCBA (Printed Circuit Board Assembly) mainboard, a light path assembly and a detection unit which are all arranged in a sensor main body, the sensor main body comprises a main body shell, a front end cover and a rear end cover, the main body shell is of a hollow cylinder structure with openings in the two ends, the front end cover and the rear end cover are arranged at the openings in the two ends of the main body shell respectively, and the front end cover is provided with a through temperature sensor communication groove; the detection unit is inserted into the temperature sensor communication groove, and the PCBA mainboard and the light path assembly are both arranged on the front end cover. According to the embodiment of the utility model, by adopting the design of two pieces of quartz glass and adjusting the light path layout, the light paths of the LED transmitting tube and the LED receiving tube are arranged at an included angle of 90 degrees, so that the interference caused by reflection is effectively reduced; and the lens base is made of aluminum, so that the problem that water mist is easy to form on the container wall and the inner surface of quartz glass is solved.

Description

TECHNICAL FIELD

[0001] The utility model relates to sensor technical field especially relates to a high accuracy turbidity sensor. BACKGROUND

[0002] Turbidity refers to the degree of hindrance when the light transmits through the suspended matter in water. The turbidity in water is generally caused by the suspended matter, which is usually soil, sand, fine organic and inorganic matter, plankton, microorganism and colloid matter, etc. The turbidity of water is not only related to the content of the suspended matter in water, but also related to their size, shape and refractive index, etc. The suspended particles in water will diffuse the incident light, and the experimental research and theoretical calculation show that the ratio of scattered light to transmitted light is linearly related to the turbidity.

[0003] The turbidity sensor usually uses the 90-degree direction scattered light as the test signal, so that the unit of the test is NTU. The scattered light is linearly related to the turbidity in multiple segments, so the sensor needs to be calibrated at multiple points. Moreover, the intensity of the light source and the temperature change will affect the accuracy of the measurement results.

[0004] The existing turbidity sensor usually uses single quartz glass as the protective material of the optical system. The single quartz glass causes light to be refracted inside the glass, which affects the measurement accuracy. Moreover, due to the unreasonable design of the light channel, the sensor has requirements for the volume of the test container. For example, the distance between the sensor head and the bottom or the periphery of the container requires a large distance to prevent the container wall and the container bottom from reflecting light and causing large measurement errors. When testing in an environment with high and low temperature changes, water mist is easily formed on the inner surface of the quartz glass, which seriously affects the detection accuracy. Therefore, there is an urgent need for a new high-precision turbidity sensor. SUMMARY

[0005] In view of the above problems, the utility model is provided to overcome the above problems or at least partially solve the above problems.

[0006] The utility model provides a kind of high-precision turbidity sensor, the high-precision turbidity sensor includes: sensor main body, PCBA mainboard, optical path component and detection unit, wherein, the PCBA mainboard, optical path component and detection unit are all set in the sensor main body;The sensor main body includes main body shell, front end cover and rear end cover, the main body shell is the hollow cylinder structure of two ends opening, the front end cover and rear end cover are respectively set in the two ends opening of the main body shell, the front end cover is provided with the temperature sensor communication slot of through, the detection unit is inserted in the temperature sensor communication slot, the PCBA mainboard and optical path component are all set on the front end cover, and the optical path component and detection unit are electrically connected with the PCBA mainboard.

[0007] The light path assembly comprises an LED emitting tube, an LED receiving tube, quartz glass, and a lens base; the lens base is arranged on the side of the front end cover away from the main body shell, two through inclined light beam through-slots are formed in the lens base, and the two light beam through-slots are perpendicular to each other; the top of the two light beam through-slots is respectively provided with the LED emitting tube and the LED receiving tube, the LED emitting tube and the LED receiving tube are both welded and fixed on the PCBA main board, and the light beam emitting path of the LED emitting tube and the light beam receiving path of the LED receiving tube are the same as the extension direction of the light beam through-slots; the bottom of the two light beam through-slots is respectively embedded with two parallel quartz glasses, the light beam emitting path of the LED emitting tube and the light beam receiving path of the LED receiving tube pass through the two quartz glasses respectively, and the focal points of the light beam emitting path of the LED emitting tube and the light beam receiving path of the LED receiving tube are located at a predetermined distance below the two quartz glasses.

[0008] The material of the lens base is 6063 aluminum.

[0009] Optionally, the emission frequency of the LED emitting tube is 15KHZ.

[0010] Optionally, the sensor main body further comprises a PG7 waterproof connector and a sensor wire harness, the side of the rear end cover away from the main body shell is connected with the PG7 waterproof connector, the PG7 waterproof connector is connected with the sensor wire harness, and the sensor wire harness is welded and fixed with the PCBA main board.

[0011] Optionally, the front end cover is provided with a main board support table at the end facing the main body shell, the PCBA main board is arranged on the main board support table, the side of the PCBA main board close to the main board support table is connected with a front end cover pressing plate, a pressing plate mounting hole is formed in the main board support table at a position corresponding to the front end cover pressing plate, a pressing plate screw is screwed in the pressing plate mounting hole, and the front end cover pressing plate is fixedly connected with the main board support table through the pressing plate screw.

[0012] Optionally, the connection gap between the PCBA main board and the main board support table is filled with EVA foam.

[0013] Optionally, the detection unit comprises a temperature sensor shell, a plug-in temperature resistor, and a resistance connecting line; the plug-in temperature resistor is installed in the temperature sensor shell, the temperature sensor shell is plugged into the temperature sensor communication slot, and the plug-in temperature resistor is electrically connected with the PCBA main board through the resistance connecting line.

[0014] Optionally, the front mounting hole is arranged in one end of the main body shell corresponding to the front end cover, and a front fastening screw is arranged in the front mounting hole.

[0015] Optionally, the first rubber sealing ring is arranged at the connecting gap between the front end cover and the main body shell.

[0016] Optionally, the rear mounting hole is arranged in one end of the main body shell corresponding to the rear end cover, and a rear fastening screw is arranged in the rear mounting hole.

[0017] Optionally, the second rubber sealing ring is arranged at the connecting gap between the rear end cover and the main body shell.

[0018] The technical scheme provided in the embodiment of the utility model has at least the following technical effects or advantages:

[0019] The embodiment of the utility model adopts the design of double pieces of quartz glass, refractive light is isolated from the optical system, the length of the light channel is deepened by arranging the light beam through groove in the lens base, and the interference caused by reflection is reduced; the light path of the LED emitting tube and the LED receiving tube is arranged at a 90-degree angle by adjusting the light path layout, the light beam point is focused on a position 1.4mm below the bottom plane of the quartz glass, and the interference of the reflected light of the container wall and the container bottom is solved; the material of the lens base is 6063 aluminum, the thermal conductivity of aluminum is 220W / mK, the thermal conductivity of quartz glass is 1.1W / mK, the thermal conductivity of aluminum is much larger than that of quartz glass, if the sensor main body cavity has a small amount of water vapor, the water vapor will preferentially adhere to the surface of the lens base at low temperature, and will not adhere to the inner surface of the quartz glass, and the problem that the container wall and the container quartz glass inner surface are prone to water mist is solved.

[0020] The above description is only a summary of the technical scheme of the utility model, in order to more clearly understand the technical means of the utility model, the content of the specification can be implemented, and in order to make the above and other purposes, characteristics and advantages of the utility model more obvious and easy to understand, the specific embodiment of the utility model will be described below. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical scheme in the embodiment of the utility model, the drawings needed in the embodiment will be briefly introduced below, and obviously, the drawings in the following description are only some embodiments of the utility model, and those skilled in the art can also obtain other drawings according to these drawings without creating creative labor.

[0022] Figure 1The explosion structure schematic view of the high-precision turbidity sensor,

[0023] Figure 2 The assembly structure schematic view of the high-precision turbidity sensor,

[0024] Figure 3 The connection structure side view of the PCBA mainboard,

[0025] Figure 4 The isometric view of the front end cover,

[0026] Figure 5 The bottom surface structure schematic view of the front end cover.

[0027] Marked with the following figure:

[0028] 1, quartz glass; 2, lens base; 3, front fastening screw; 4, front end cover; 5, first rubber sealing ring; 6, resistance shell; 7, plug-in temperature resistance; 8, EVA foam; 9, LED emitting tube; 10, LED receiving tube; 11, front end cover pressing plate; 12, pressing plate screw; 13, PCBA mainboard; 14, main body shell; 15, second rubber sealing ring; 16, rear fastening screw; 17, rear end cover; 18, PG7 waterproof connector; 19, sensor wire harness; 20, front mounting hole; 21, resistance connecting line; 22, rear mounting hole; 23, temperature sensor communication groove; 24, light beam through groove; 25, mainboard support table; 26, pressing plate mounting hole. DETAILED DESCRIPTION

[0029] The exemplary embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.

[0030] In order to make the technical personnel in the art better understand the present application scheme, the technical scheme in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. The preferred embodiments of the present application are given in the drawings. The present application can be realized in many different forms, and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0031] Unless otherwise specifically stated, the various raw materials, instruments and equipment used in the present application can be purchased from the market or can be prepared by existing methods.

[0032] Figure 1 The structure schematic view of the high-precision turbidity sensor provided by the embodiments of the present application, Figure 2The utility model discloses a high-precision turbidity sensor's assembly structure schematic diagram, Figure 3 It is the connection structure side view of PCBA mainboard 13, and reference Figures 1-3 As shown in the figure, the high-precision turbidity sensor includes a sensor main body, a PCBA mainboard 13, a light path assembly and a detection unit, wherein the PCBA mainboard 13, the light path assembly and the detection unit are all arranged in the sensor main body; the sensor main body includes a main body shell 14, a front end cover 4 and a rear end cover 17, the main body shell 14 is a hollow cylinder structure with two open ends, the front end cover 4 and the rear end cover 17 are arranged at the two open ends of the main body shell 14 respectively, the front end cover 4 is provided with a through temperature sensor communication groove 23, the detection unit is inserted in the temperature sensor communication groove 23, and the PCBA mainboard 13 and the light path assembly are both arranged on the front end cover 4, and the light path assembly and the detection unit are both electrically connected with the PCBA mainboard 13.

[0033] Figure 4 It is the isometric view of front end cover 4, Figure 5 It is the bottom surface structure schematic diagram of front end cover 4, and reference Figures 4-5 As shown in the figure, the light path assembly includes an LED emitting tube 9, an LED receiving tube 10, a quartz glass 1 and a lens base 2; the lens base 2 is arranged on the side of the front end cover 4 away from the main body shell 14, two through inclined light beam through grooves 24 are formed in the lens base 2, and the two light beam through grooves 24 are perpendicular to each other; the LED emitting tube 9 and the LED receiving tube 10 are arranged at the top of the two light beam through grooves 24 respectively, the LED emitting tube 9 and the LED receiving tube 10 are both welded and fixed on the PCBA mainboard 13, the light beam emitting path of the LED emitting tube 9 and the light beam receiving path of the LED receiving tube 10 are the same as the extension direction of the light beam through grooves 24, and two parallel quartz glasses 1 are embedded at the bottom of the two light beam through grooves 24 respectively; the light beam emitting path of the LED emitting tube 9 and the light beam receiving path of the LED receiving tube 10 pass through the two quartz glasses 1 respectively, and the focal points of the light beam emitting path of the LED emitting tube 9 and the light beam receiving path of the LED receiving tube 10 are located below the two quartz glasses 1 at a predetermined distance; for example, in the embodiment of the utility model, the material of the lens base 2 is 6063 aluminum, the LED emitting tube 9 emits an infrared light beam with a frequency of 15KHZ, the light beam passes through the light beam through groove 24 of the lens base 2, penetrates the quartz glass 1 and irradiates the suspended matter in water, the predetermined distance is, for example, 1.4mm below the bottom plane of the quartz glass 1, the scattered light passes through the quartz glass 1 again, then passes through the light beam through groove 24 of the lens base 2, and the received light is sent to the PCBA mainboard 13 to detect and amplify the signal.

[0034] The front end cover 4 is provided with a mainboard support table 25 at one end of the main body shell 14, the PCBA mainboard 13 is arranged on the mainboard support table 25, and the front end cover pressing plate 11 is connected to one side of the PCBA mainboard 13 close to the mainboard support table 25, the mainboard support table 25 is provided with a pressing plate mounting hole 26 at a position corresponding to the front end cover pressing plate 11, and the pressing plate mounting hole 26 is screwed with a pressing plate screw 12, and the front end cover pressing plate 11 is fixedly connected with the mainboard support table 25 through the pressing plate screw 12.

[0035] In the embodiment of the utility model, in order to avoid the problem of light leakage of LED emitting tube 9, EVA bubble cotton 8 is filled and arranged at the connecting gap between PCBA mainboard 13 and mainboard support table 25.

[0036] The detection unit comprises a resistance shell 6, a plug-in temperature resistance 7 and a resistance connecting line 21, the plug-in temperature resistance 7 is installed in the resistance shell 6, the resistance shell 6 is inserted in the temperature sensor communication groove 23, and the plug-in temperature resistance 7 is electrically connected with the PCBA mainboard 13 through the resistance connecting line 21, in the embodiment of the utility model, the temperature sensor shell 6 is made of stainless steel, has excellent heat conduction performance, and the current temperature of the solution to be detected can be quickly transmitted to the plug-in temperature resistance 7 through the resistance shell 6 of stainless steel, and the plug-in temperature resistance 7 converts the electric signal to the PCBA mainboard 13, thereby overcoming the slow reaction time.

[0037] The sensor main body further comprises a PG7 waterproof joint 18 and a sensor wire harness 19, the rear end cover 17 is connected with the PG7 waterproof joint 18 at one side away from the main body shell 14, the PG7 waterproof joint 18 is connected with the sensor wire harness 19, and the sensor wire harness 19 is welded and fixed with the PCBA mainboard 13 and electrically connected, so that the detection result can be transmitted to other external equipment through the sensor wire harness 19.

[0038] In the embodiment of the utility model, the main body shell 14 is provided with a front mounting hole 20 at one end corresponding to the front end cover 4, the front mounting hole 20 is provided with a front fastening screw 3, and the front end cover 4 is screwed and fixed on the main body shell 14 through the front fastening screw 3.

[0039] The connecting gap between the front end cover 4 and the main body shell 14 is provided with a first rubber sealing ring 5, so as to improve the sealing effect of the connecting gap.

[0040] In the embodiment of the utility model, the rear mounting hole 22 is set in one end of the rear end cover 17 corresponding to the main body shell 14, the rear fastening screw 16 is arranged in the rear mounting hole 22, and the rear end cover 17 is screwed and fixed on the main body shell 14 through the rear fastening screw 16.

[0041] The second rubber sealing ring 15 is arranged at the connecting gap between the rear end cover 17 and the main body shell 14, so that the sealing effect of the connecting gap is improved.

[0042] The embodiment of the utility model discloses a design of double quartz glass 1, which isolates the refraction of the optical system. The length of the light channel is deepened by setting the light beam through groove 24 of the lens base 2, and the interference caused by reflection is reduced. By adjusting the light path layout, the light path of the LED emitting tube 9 and the LED receiving tube 10 is arranged at a 90-degree angle, and the light beam point is focused on a position 1.4 mm below the bottom plane of the quartz glass 1 to solve the interference of the container wall and the container bottom reflection. The material of the lens base 2 is 6063 aluminum, the thermal conductivity of aluminum is 220 W / mK, and the thermal conductivity of quartz glass 1 is 1.1 W / mK. Since the thermal conductivity of aluminum is much greater than that of quartz glass 1, if the sensor main body cavity has a small amount of water vapor, it will preferentially adhere to the surface of the low-temperature lens base 2, and will not adhere to the inner surface of the quartz glass 1, solving the problem of water mist on the container wall and the inner surface of the quartz glass 1.

[0043] In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the application can be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been described in detail in order to not obscure the understanding of this description.

[0044] Similarly, it is to be understood that the embodiments of the application can be over-simplified to aid in the understanding of one or more aspects of the various applications. In the above description of the exemplary embodiments of the application, various features of the application are sometimes grouped together in a single embodiment, figure, or description of a related aspect. However, this method of disclosure should not be interpreted as reflecting a necessity that the application requires more features than are explicitly recited in each claim. Rather, inventive aspects lie in less than all features of a single disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim acting as a separate embodiment of the application. The claims are not to be interpreted under the doctrine of equivalents.

[0045] It should be noted that the above embodiments illustrate the present application rather than limit the present application, and the skilled in the art can design alternative embodiments without departing from the scope of the appended claims.

Claims

1. A high-precision turbidity sensor characterized by, The high-precision turbidity sensor comprises a sensor body, a PCBA mainboard, a light path assembly and a detection unit, wherein the PCBA mainboard, the light path assembly and the detection unit are arranged in the sensor body; the sensor body comprises a body shell, a front end cover and a rear end cover, the body shell is a hollow cylindrical structure with two open ends, the front end cover and the rear end cover are arranged at the two open ends of the body shell respectively, the front end cover is provided with a through temperature sensor communication slot, the detection unit is inserted into the temperature sensor communication slot, the PCBA mainboard and the light path assembly are arranged on the front end cover, and the light path assembly and the detection unit are electrically connected with the PCBA mainboard. The light path assembly comprises an LED emitting tube, an LED receiving tube, quartz glass and a lens base; the lens base is arranged on the side of the front end cover away from the body shell, two through inclined light beam through slots are formed in the lens base, and the two light beam through slots are perpendicular to each other; the LED emitting tube and the LED receiving tube are arranged at the top of the two light beam through slots respectively, the LED emitting tube and the LED receiving tube are welded and fixed on the PCBA mainboard, the light beam emitting path of the LED emitting tube and the light beam receiving path of the LED receiving tube are the same as the extension direction of the light beam through slots; two parallel quartz glasses are embedded at the bottom of the two light beam through slots respectively, the light beam emitting path of the LED emitting tube and the light beam receiving path of the LED receiving tube pass through the two quartz glasses respectively, and the focal points of the light beam emitting path of the LED emitting tube and the light beam receiving path of the LED receiving tube are located at a predetermined distance below the two quartz glasses. The material of the lens base is 6063 aluminum.

2. The high-precision turbidity sensor according to claim 1, characterized in that: The emitting frequency of the LED emitting tube is 15KHZ.

3. The high-precision turbidity sensor according to claim 1, characterized in that: The sensor body further comprises a PG7 waterproof joint and a sensor wire harness, the side of the rear end cover away from the body shell is connected with the PG7 waterproof joint, the PG7 waterproof joint is connected with the sensor wire harness, and the sensor wire harness is welded and fixed with the PCBA mainboard.

4. The high-precision turbidity sensor according to claim 1, characterized in that: The front end cover is provided with a mainboard support table at one end facing the body shell, the PCBA mainboard is arranged on the mainboard support table, the front end cover pressing plate is connected to the side of the PCBA mainboard close to the mainboard support table, a pressing plate mounting hole is formed in the mainboard support table corresponding to the position of the front end cover pressing plate, a pressing plate screw is screwed into the pressing plate mounting hole, and the front end cover pressing plate is fixedly connected with the mainboard support table through the pressing plate screw.

5. The high-precision turbidity sensor according to claim 4, characterized in that: An EVA foam is filled in the connection gap between the PCBA mainboard and the mainboard support table.

6. The high-precision turbidity sensor according to claim 1, characterized in that: The detection unit comprises a temperature sensor shell, a plug-in temperature resistor and a resistance connecting line; the plug-in temperature resistor is installed in the temperature sensor shell, the temperature sensor shell is inserted into the temperature sensor communication slot, and the plug-in temperature resistor is electrically connected with the PCBA mainboard through the resistance connecting line.

7. The high-precision turbidity sensor according to claim 1, characterized in that: The front mounting hole is arranged in one end of the main body shell corresponding to the front end cover, and a front fastening screw is arranged in the front mounting hole.

8. The high-precision turbidity sensor according to claim 7, characterized in that: The first rubber sealing ring is arranged at the connecting gap between the front end cover and the main body shell.

9. The high precision turbidity sensor of claim 1, wherein: The rear mounting hole is arranged in one end of the main body shell corresponding to the rear end cover, and a rear fastening screw is arranged in the rear mounting hole.

10. The high precision turbidity sensor of claim 9, wherein: The second rubber sealing ring is arranged at the connecting gap between the rear end cover and the main body shell.

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