Laser cleaning device for refractometer

Abstract

The utility model relates to a laser cleaning device for a refractometer. The laser cleaning device comprises a refractometer prism, an optical fiber and a laser, the refractometer prism is embedded in the end face of the online refractometer and comprises a first plane and a second plane; the first plane is exposed out of the outer surface of the end face of the online refractometer and is in contact with to-be-detected liquid; the second plane is opposite to the first plane and is positioned in the online refractometer; the optical fiber is arranged in the online refractometer and comprises a first end face and a second end face; the first end face is opposite to a second plane of the refractometer prism, and the second end face is connected with the laser; the laser is used for generating a laser beam capable of cleaning dirt attached to the first plane. The cleaning degree of cleaning can be greatly improved, noise and vibration are avoided, no mechanical operation part exists, energy is saved, cleaning can be conducted while measurement is conducted, and the measurement precision is not affected.

Description

Technical Field

[0001] This utility model relates to the field of liquid detection technology, and in particular to a refractometer laser cleaning device. Background Technology

[0002] In existing technologies, refractive index is one of the important optical parameters of liquids. It allows us to understand the optical properties, purity, concentration, and dispersion of liquids. Other parameters (such as temperature) are also closely related to refractive index. Therefore, the measurement of liquid refractive index is of great significance in fields such as chemical engineering, pharmaceuticals, food processing, and petroleum.

[0003] A refractometer is an instrument that uses the critical angle imaging method of total internal reflection to measure the refractive index of liquids. In manufacturing fields such as machining, refractometers are commonly used to continuously and in real-time sample and measure the liquid being tested in tanks or pipelines to monitor changes in liquid parameters during production and to address them promptly to ensure product quality.

[0004] However, in actual industrial measurement scenarios, the liquid being measured is often mixed with impurities. These impurities can adhere to the measurement window of the refractometer as the liquid flows, causing the refractometer to malfunction or even become inaccurate, seriously affecting quality control in the production process. For example, cutting fluids used in machining inevitably mix with oil droplets, sludge, and other impurities during recycling, forming a suspension that is difficult to filter and remove, and easily adheres to the surface of the glass prism, causing the refractometer to malfunction.

[0005] In existing technologies, the industry commonly employs various methods such as ultrasonic cleaning and electric brush cleaning to clean refractometers, but the results are unsatisfactory. Therefore, cleaning has become a major pain point in cutting fluid measurement and urgently needs to be addressed. Utility Model Content

[0006] The technical problem to be solved by this utility model is to provide a laser cleaning device for refractometers, so as to solve the problem of refractometer cleaning in the prior art.

[0007] According to one aspect of the present invention, a laser cleaning device for a refractometer is provided, comprising:

[0008] Refractometer prism, optical fiber, laser;

[0009] The refractometer prism is embedded on the end face of the online refractometer and includes a first plane and a second plane;

[0010] The first plane is exposed on the outer surface of the end face of the online refractometer and is in contact with the liquid to be tested;

[0011] The second plane is positioned opposite to the first plane and is located inside the online refractometer;

[0012] The optical fiber is disposed inside the online refractometer and includes a first end face and a second end face; the first end face is disposed opposite to the second plane of the refractometer prism, and the second end face is connected to the laser.

[0013] The laser is used to generate a laser beam capable of cleaning dirt adhering to the first plane.

[0014] The laser is located inside the online refractometer; the optical fiber can be lengthened or shortened according to the position of the laser.

[0015] The laser is configured as an accessory of the online refractometer and is located outside the online refractometer as needed; the optical fiber can be lengthened or shortened according to the position of the laser.

[0016] The laser generated by the laser can enter the second end face of the optical fiber, and after being conducted by the optical fiber, it exits from the first end face, enters the second plane of the refractometer prism, passes through the refractometer prism, and exits from the first plane of the refractometer prism.

[0017] The laser generates a wavelength of 200nm to 400nm or 850nm to 1100nm and a power of 20W to 100W.

[0018] A beam expander is provided on the first end face of the optical fiber; the laser beam passes through the beam expander at a set cone angle and forms a light spot on the first plane of the refractometer prism that can effectively cover dirt.

[0019] The laser beam does not coincide with the measurement beam of the online refractometer; preferably, the angle between the laser beam and the normal of the second plane of the refractometer prism is within 15°.

[0020] An extinction material is provided in the area of ​​the second plane of the refractometer prism where reflected light exists to absorb the reflected energy of the laser beam; or a curved reflector is provided at the corresponding position of the area of ​​the second plane of the refractometer prism where reflected light exists to reflect the reflected energy of the laser beam back into the refractometer prism.

[0021] The first end face of the optical fiber can move within a set range according to the position of the dirt attached to the first plane, so that the laser beam generated by the laser can enter the second plane and the first plane perpendicularly and accurately cover the dirt attached to the first plane.

[0022] The laser can adjust the output power, output time, and output duration of the laser beam according to the control of the online refractometer; the online refractometer controls the laser based on the location, area, and intensity of the dirt attached to the first plane of the refractometer prism and the presence of measuring liquid in the measuring pipe.

[0023] The beneficial effects of adopting the above scheme are:

[0024] The laser cleaning device for refractometers in this embodiment of the invention greatly improves the cleanliness of the cleaning compared to the traditional method of cleaning with ultrasonic waves and electric brushes. Moreover, it is silent and vibration-free, has no mechanical moving parts, saves energy, and can clean while measuring without affecting the measurement accuracy.

[0025] In various embodiments of this application, a high-energy laser is used for cleaning, which can instantly heat up the dirt and melt it, peeling the dirt off the measuring prism and carrying it away with the flowing liquid. This ensures the cleanliness of the online refractometer's measuring window, effectively avoiding the impact of residues on the accuracy of subsequent measurements and improving the reliability of the measurement data. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structural principle of the laser cleaning device for the refractometer provided in Embodiment 1 of this utility model;

[0027] Figure 2 This is a schematic diagram illustrating the structural principle of the refractometer laser cleaning device provided in Embodiment 2 of this utility model. Detailed Implementation

[0028] The principles and features of this utility model are described below with reference to the accompanying drawings. The examples given are only for explaining this utility model and are not intended to limit the scope of this utility model. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0029] Refractometers are primarily used in industrial production settings to measure the refractive index and concentration of liquids flowing in pipelines. They are typically installed on a flow-through container connected to the pipeline, with their optical measurement window in contact with the liquid being measured. This allows for the measurement of the liquid's refractive index and concentration using the principle of critical total internal reflection. However, in the application of online refractometers, it has been found that the liquid being measured often contains dirt and oil (such as cutting fluid), which can easily adhere to the prism surface of the refractometer's optical measurement window, leading to inaccurate measurements or even malfunction.

[0030] The industry typically uses ultrasonic cleaning devices, which involve installing an ultrasonic cleaner on a flow-through tank and aligning the ultrasonic probe with the measurement window of the online refractometer for cleaning. However, during use, it was found that when the liquid being tested contains a lot of oil, the ultrasonic waves emulsify the oil, causing it to adhere more tightly to the prism surface and creating a fogging effect, making the application far from ideal.

[0031] In various embodiments of this application, the online refractometer can have a built-in (or external) laser to generate a high-energy laser beam. This beam is transmitted through an optical fiber, projected from inside the online refractometer onto the bottom surface of the refractometer prism, and passes through the refractometer prism without loss. It is then projected onto the measuring surface of the refractometer prism and exits from the measuring surface into the liquid to be tested. If dirt accumulates on the measuring surface, the laser beam will irradiate the dirt, heating the attachment point and melting and peeling it off from its root. The dirt is then carried away by the flowing liquid to be tested, thus cleaning the measuring surface. Since the laser exits through the measuring window inside the online refractometer, the laser energy can be applied to the dirt with maximum efficiency. A low-power laser can be used to achieve the cleaning purpose, saving energy.

[0032] Example 1

[0033] like Figure 1 As shown, Embodiment 1 of this utility model provides a laser cleaning device for a refractometer, comprising:

[0034] Refractometer prism 100, optical fiber 200, laser 300;

[0035] The refractometer prism 100 is embedded on the end face of the online refractometer and includes a first plane and a second plane. The first plane is the measuring surface of the refractometer prism 100, which is exposed on the outer surface of the end face of the online refractometer and is in contact with the liquid to be tested. The second plane is the bottom surface of the refractometer prism 100, which is opposite to the first plane and is located inside the online refractometer.

[0036] An optical fiber 200 is disposed inside the online refractometer and includes a first end face and a second end face. The first end face of the optical fiber 200 is aligned with the second plane of the refractometer prism 100, and the second end face of the optical fiber 200 is connected to the laser 300.

[0037] Laser 300 is located inside the online refractometer.

[0038] In one embodiment of this application, compared with the traditional method of cleaning using ultrasonic waves and electric brushes, the cleanliness of the cleaning is greatly improved. The high-energy laser generated by the laser 300 inside the online refractometer is transmitted through the optical fiber 200 and the refractometer prism 100 and emitted from the online refractometer measurement window. It can directly act on the dirt attached to the measurement window and melt the dirt from the root by irradiating the attachment surface of the dirt. Therefore, it can deeply remove various residues on the refractometer prism 100, including highly viscous and easily adhered sample components, ensuring the cleanliness of the measurement window, effectively avoiding the impact of residues on the accuracy of subsequent measurements, and improving the reliability of measurement data.

[0039] Specifically, during cleaning, the laser 300 generates a high-energy laser beam, which is transmitted through the optical fiber 200. The beam reaches the first end face of the optical fiber 200, which is aligned with the second plane of the refractometer prism 100. This allows the beam emitted from the optical fiber 200 to enter through the second plane of the refractometer prism 100, pass through the refractometer prism 100, and exit from the first plane of the refractometer prism 100. The high-energy laser generated by the laser 300 then irradiates the dirt accumulated on the first plane of the refractometer prism 100, causing it to melt and decompose.

[0040] In this embodiment, the laser 300 generates a laser of a specific wavelength that can pass through the refractometer prism 100 without loss, without causing the refractometer prism 100 to heat up and affect the measurement or cause structural damage. At the same time, the laser energy of this specific wavelength can be fully absorbed by the dirt to obtain the maximum cleaning effect. In addition, the laser energy of this specific wavelength can also be absorbed by the liquid to be tested, which can avoid high-energy laser damage to the pipeline or reflection back to the online refractometer, causing instrument damage.

[0041] In this embodiment, the first end face of the optical fiber 200 has a specific shape, which can make the emitted laser beam present a certain cone angle, so that the laser beam forms a light spot on the first plane of the refractometer prism 100 that can effectively cover dirt.

[0042] In this embodiment, the laser beam generated by the laser 300 can pass perpendicularly through the refractometer prism 100 without interfering with the measurement beam of the online refractometer. Therefore, cleaning and measurement can be performed simultaneously without affecting each other.

[0043] Example 2

[0044] like Figure 2 As shown, Embodiment 2 of this utility model provides a laser cleaning device for a refractometer. Based on Embodiment 1, this embodiment includes:

[0045] Refractometer prism 100, optical fiber 200, optical fiber interface 400, external optical fiber 500, external laser 300;

[0046] The refractometer prism 100 is embedded on the end face of the online refractometer and includes a first plane and a second plane. The first plane is the measuring surface of the refractometer prism 100, which is exposed on the outer surface of the end face of the online refractometer and is in contact with the liquid to be tested. The second plane is the bottom surface of the refractometer prism 100, which is opposite to the first plane and is located inside the online refractometer.

[0047] The optical fiber 200 is located inside the online refractometer and includes a first end face and a second end face. The first end face of the optical fiber 200 is aligned with the second plane of the refractometer prism 100, and the second end face of the optical fiber 200 is connected to the optical fiber interface 400.

[0048] The fiber optic interface 400 is embedded in the housing of the online refractometer and includes a first interface and a second interface. The first interface is connected to the second end face of the fiber optic cable 200, and the second interface is located outside the housing of the online refractometer.

[0049] The external optical fiber 500 is located outside the online refractometer and includes a first end face and a second end face. The first end face of the external optical fiber 500 is connected to the second interface of the optical fiber interface 400, and the second end face of the external optical fiber 500 is connected to the external laser 300.

[0050] The external laser 300 is located outside the online refractometer.

[0051] In this embodiment, the working principle is the same as in embodiment 1, except that the laser 300 is detached from the online refractometer and placed outside. This reduces the size and weight of the online refractometer and keeps the laser away from the harsh environment on site, thus ensuring the long-term reliability of the equipment.

[0052] In the above embodiments of this application, to solve the problem of cleaning the measurement window, the team designed a solution for cleaning the refractometer prism with a laser and conducted extensive experiments. Breaking with convention, the team did not use the method of setting and emitting a laser beam from the surface to be cleaned directly onto the surface of the measurement window from inside the online refractometer through the prism. This allows the laser energy to act on the root of the dirt immediately after exiting the prism, effectively removing it. This method maximizes the efficiency of laser energy, is unaffected by the liquid being tested, and can effectively remove dirt even from opaque liquids such as soy sauce. This is the fundamental design concept of this application.

[0053] In the specific design, several key design details were also taken into consideration.

[0054] Laser Wavelength Selection. The selected laser wavelength should be able to pass through the optical glass prism with no or very low loss, be effectively absorbed by dirt and the liquid being tested, and not interfere with the refractometer's measurement light. The requirement of no or very low loss passage through the prism ensures that the prism does not experience localized changes in refractive index, structural alterations, or damage during laser operation. Effective dirt absorption determines the cleaning effect, and absorption by the liquid being tested ensures that the pipe is not damaged by the laser. The requirement of not interfering with the refractometer's measurement necessitates avoiding the yellow light band used for measurement. Through comprehensive analysis and extensive experimentation by the patent applicant team, a laser wavelength range that meets the requirements was found. The ultraviolet (200nm–400nm) and near-infrared (850nm–1100nm) wavelengths meet the requirements.

[0055] Laser power selection. Clearly, higher laser power results in better cleaning, but product design requires optimization of more parameters. The overall structural design of this application provides the possibility of high-efficiency laser cleaning, thus significantly reducing the requirements for laser power. Laser power is mainly affected by parameters such as the type of liquid and dirt being tested, the size of the measurement window, and the laser beam radiation angle. Considering the parameters of the online refractometer and the application scenario, a laser output power in the range of 20W to 100W is more suitable.

[0056] Protection of the online refractometer. The laser output can be transmitted through flexible optical fiber. This transmission method allows the laser output to be close to the bottom surface of the refractometer prism, ensuring the laser beam enters the prism perpendicularly and exits perpendicularly from the prism's measurement window. This significantly reduces the space and range of laser exposure inside the refractometer. Since the laser energy is absorbed by the dirt and liquid after exiting the prism's measurement window, damage to the refractometer from this energy is not a concern; only the energy of the light reflected from the prism's medium surface needs to be considered. Theoretically, as long as perpendicular entry and exit are maintained, the energy of the reflected light does not need to be considered. However, to effectively cover the measurement window area, whether using a scanning method or a large radiation angle, there will be a certain angle between the laser beam and the prism normal, resulting in reflected energy. Considering the thickness of the prism and the size of the measurement window in actual online refractometer products, controlling the angle between the laser and the prism normal to within 15° is sufficient to effectively cover the measurement window and ensure that the reflected light is in a safe position on the bottom surface of the prism (a safe position means that it will not affect the internal precision components and is separated from the refractometer's measurement light; the angle between the measurement light and the prism normal is generally greater than 40°, meaning it will not interfere with the measurement). To better protect against the influence of reflected energy, an ablative material can be placed in the area on the bottom surface of the prism where reflected light occurs to absorb the reflected energy, or a curved reflector can be placed in this area to reflect the reflected energy back into the liquid, thus achieving a protective effect.

[0057] The radiation angle of the laser beam. Since the measurement window has a certain area, the laser beam radiation angle needs to be around 20° to effectively cover it. One solution in this application is to install a suitable beam expander at the fiber optic output end. By adjusting the parameters, a spot that meets the coverage requirements can be obtained within the measurement window. A second solution involves laser scanning and aiming. If the laser beam has a very narrow radiation angle, it will maintain extremely high laser energy density, allowing for satisfactory cleaning results with a lower-power laser. This solution designs a method to control the active scanning of the laser beam to meet the coverage requirements of the measurement window. For certain specific fields, it can be adapted to an image recognition system for targeted irradiation of dirt, achieving precise cleaning capabilities.

[0058] Furthermore, regarding laser control, the proposed solution fully utilizes the intelligent components of the refractometer to control the laser output. Firstly, the refractometer measures the presence of liquid in the pipe; if no liquid is present, laser output is disabled to prevent damage to the pipe. Secondly, data analysis from the refractometer detects the presence of dirt, activating the laser only when necessary for cleaning. Then, the laser's output power and duration can be controlled for effective cleaning of the dirt. Based on this, a scheme is designed to adjust the laser power according to the thickness and severity of the dirt, preventing excessive energy from entering the equipment. An aiming control system can also be configured for precise irradiation of the dirt.

[0059] In this application, the laser output from the laser is transmitted through optical fiber. Since optical fiber is flexible and does not take up much space, it greatly facilitates the installation of the laser. A small laser can be placed in the extended space at the tail of the refractometer to form an integrated device, or the laser can be deployed at a relatively far place outside the refractometer to meet the deployment requirements of harsh environments and confined spaces.

[0060] Compared to traditional cleaning methods using ultrasonic waves and electric brushes, the solution in this embodiment greatly improves the cleanliness of the cleaning process. Moreover, it is silent and vibration-free, has no mechanical moving parts, saves energy, and can perform cleaning while measuring without affecting the measurement accuracy.

[0061] In this embodiment, the online refractometer incorporates a built-in laser that generates a high-energy laser beam. This beam is transmitted through an optical fiber, projected from inside the online refractometer onto the bottom surface of the refractometer prism, and passes through the prism without loss. It then strikes the measuring surface of the prism and exits into the liquid to be tested. If dirt accumulates on the measuring surface, the laser beam irradiates it, heating the area where the dirt adheres to the measuring surface and melting and peeling it off from its root. The dirt is then carried away by the flowing liquid, thus cleaning the measuring surface. The laser beam exits from inside the online refractometer through the measuring window, maximizing the efficiency of the laser energy on the dirt. A low-power laser is sufficient for cleaning, saving energy. Using a high-energy laser for cleaning instantly heats and melts the dirt, peeling it off the measuring prism and carrying it away with the flowing liquid. This ensures the cleanliness of the online refractometer's measuring window, effectively preventing residue from affecting the accuracy of subsequent measurements and improving the reliability of the measurement data.

[0062] In summary, in the various embodiments of this utility model, the use of high-energy lasers for cleaning can instantly heat up the dirt and melt it, peeling the dirt off the measuring prism and carrying it away with the flowing liquid. This ensures the cleanliness of the online refractometer's measuring window, effectively avoiding the impact of residues on the accuracy of subsequent measurements and improving the reliability of the measurement data.

[0063] Those skilled in the art will understand that embodiments of this invention can be provided as methods, systems, or computer program products. Therefore, this invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this invention can take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0064] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing device, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0065] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0066] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0067] Obviously, those skilled in the art can make various modifications and variations to this utility model without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this utility model and their equivalents, this utility model also intends to include these modifications and variations.

Claims

1. A refractometer laser cleaning device, characterized by, The application relates to an online refractometer, which comprises a refractometer prism, an optical fiber and a laser. The refractometer prism is embedded on the end surface of the online refractometer and comprises a first plane and a second plane. The first plane is exposed on the outer surface of the end surface of the online refractometer and is in contact with a liquid to be detected. The second plane is oppositely arranged to the first plane and is located in the interior of the online refractometer. The optical fiber is arranged in the interior of the online refractometer and comprises a first end surface and a second end surface; the first end surface is oppositely arranged to the second plane of the refractometer prism, and the second end surface is connected to the laser. The laser is used to generate a laser beam capable of cleaning the dirt attached to the first plane. The laser is arranged in the interior of the online refractometer; and the optical fiber can be lengthened or shortened according to the position of the laser.

2. The refractometer laser cleaning device of claim 1, wherein, The laser is arranged as a component of the online refractometer according to needs and is arranged outside the online refractometer; and the optical fiber can be lengthened or shortened according to the position of the laser.

3. The refractometer laser cleaning device of claim 1, wherein, The laser generated by the laser can enter the second end surface of the optical fiber, is conducted through the optical fiber, is emitted from the first end surface, enters the second plane of the refractometer prism and is emitted from the first plane of the refractometer prism.

4. The refractometer laser cleaning device of claim 1, wherein, The laser generated by the laser has a wavelength of 200nm-400nm or 850nm-1100nm and a power of 20W-100W.

5. The refractometer laser cleaning device of claim 1, wherein, The first end surface of the optical fiber is provided with an expansion mirror; the laser beam passes through the expansion mirror and forms a light spot capable of effectively covering the dirt on the first plane of the refractometer prism at a set cone angle.

6. The refractometer laser cleaning device of claim 1, wherein, The laser beam does not coincide with the measuring beam of the online refractometer; and the included angle between the laser beam and the normal line of the second plane of the refractometer prism is within 15 degrees.

7. The refractometer laser cleaning device of claim 1, wherein, The second plane of the refractometer prism is provided with a light-absorbing material in the region where the reflected light exists to absorb the reflected energy of the laser beam; or a curved mirror is arranged at the position corresponding to the region where the reflected light exists on the second plane of the refractometer prism to reflect the reflected energy of the laser beam into the refractometer prism again.

8. The refractometer laser cleaning device of claim 1, wherein, The first end surface of the optical fiber can be moved within a set range according to the position of the dirt attached to the first plane, so that the laser beam generated by the laser can vertically enter the second plane and the first plane and accurately cover the dirt attached to the first plane.

9. The refractometer laser cleaning device of claim 1, wherein, The laser can adjust the output power, output time and output duration of the laser beam according to the control of the online refractometer; and the online refractometer controls the laser according to the position, area and intensity of the dirt attached to the first plane of the refractometer prism and whether there is a measuring liquid in the measuring pipeline.

10. The refractometer laser cleaning device of claim 1, wherein, ​

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