A water pressure stability detection device and detection method for a water-guided laser water system

Abstract

The present invention belongs to the technical field of water-guided laser, and relates to a water pressure stability detection device and detection method of a water-guided laser water system, comprising: a light source, a beam splitter, a first reflector, a second reflector, a camera, and a host computer located around a water storage cavity, wherein the water storage cavity is connected to a high-pressure water system; a light beam emitted by a light source is split into a detection light and a reference light, the detection light penetrates the water storage cavity and the high-pressure water body therein, and then performs superposition interference with the reference light, and the water pressure stability of the high-pressure water source is detected by comparing the superposition interference image with the reference image. The present invention realizes photoelectric detection of the water pressure stability of the water-guided laser high-pressure water system with high precision, and is helpful for detecting whether the water pressure stability of the high-pressure water system meets the requirements of water-guided laser processing. The present invention has high detection precision and can perform stable and continuous detection for a long time.

Description

Technical Field

[0001] The invention belongs to the technical field of water-guided lasers and relates to a water pressure stability detection device and a detection method for a water-guided laser water system. Background Art

[0002] With the continuous development of industrial technology, high-pressure water systems have been widely used in many fields such as cleaning, cutting and crushing. Water-guided laser processing is an advanced processing technology that uses water as a conductive medium to couple laser energy in a stable water flow to process the surface of the workpiece. It combines the advantages of laser processing and water cooling, and has the characteristics of high efficiency, precision, low thermal impact and environmental protection. It is currently mainly used in cutting, trimming, etc. As a new technical means, water-guided laser processing combines the strong impact of high-pressure water and the high energy density of laser, providing new possibilities for material processing and treatment. The principle of water-guided laser is that after the laser is incident at a certain angle, it is totally reflected at the interface between water and air. The key to the stable transmission of laser in water is that the high-pressure water jet can stably maintain a laminar state, which makes the construction of a stable high-pressure water system particularly critical. As a carrier of laser, the stability of high-pressure water has a great influence on the laser coupling output efficiency and processing efficiency of water-guided laser. Therefore, the water pressure stability of the high-pressure water system in water-guided laser processing is crucial to ensure the stable operation of water-guided laser.

[0003] However, in the existing water-guided laser processing technology, the water pressure detection method mainly relies on physical measuring equipment such as pressure sensors or flow meters. Although these methods can monitor water pressure to a certain extent, they often have problems such as low accuracy, slow response speed, and inability to monitor stably for a long time, which greatly affects the precision, reliability and stability of water-guided laser processing.

[0004] Therefore, in order to obtain real-time monitoring data of water pressure and further explore the influence of water pressure stability on the real-time water-guided laser processing, a more accurate water pressure stability detection device or detection method for the water-guided laser high-pressure water system is needed to solve this technical problem. Summary of the invention

[0005] The technical solution adopted by the present invention to solve the technical problem is: a water pressure stability detection device for a water-guided laser water system, comprising: a light source, a beam splitter, a first reflector, a water storage cavity, a second reflector, a high-pressure water system, a camera, and a host computer, wherein the water storage cavity is a transparent water tank provided with a water inlet and a water outlet, the water inlet of the water storage cavity is connected to the water outlet of the high-pressure water system, and the high-pressure water system is used to provide a high-pressure water source for the water-guided laser; the emission direction of the light source is toward the beam splitter, and the beam splitter splits the incident light L1 emitted by the light source into reflected light L2 and refracted light L3; the reflected light L2 penetrates the water storage cavity and irradiates the second reflector and then reflects to generate reflected light L4, and the reflected light L4 irradiates the beam splitter and then refracts to generate refracted light L6 toward the camera lens; the refracted light L3 irradiates the first reflector and then reflects to generate reflected light L5, and the reflected light L5 irradiates the beam splitter and then reflects to generate reflected light L7 toward the camera lens;

[0006] The camera is an industrial CCD camera, and the camera 7 data is connected to the host computer; the host computer is used to process the image uploaded by the camera in real time and match it with the reference image, analyze the similarity between the two, and thus obtain the stability of the water pressure in the high-pressure water system.

[0007] Preferably, the light source is a laser light source, and the emitted light of the light source is laser.

[0008] Preferably, the reflected light L4 is emitted through the second reflector, penetrates the water storage cavity and then irradiates the beam splitter.

[0009] Preferably, the beam splitter and the second reflector are located at two opposite sides of the water storage cavity.

[0010] More preferably, the beam splitter and the second reflector are located at the upper and lower sides of the water storage cavity respectively.

[0011] More preferably, the beam splitter is located at the lower side of the water storage cavity, and the second reflecting mirror is located at the upper side of the water storage cavity.

[0012] Preferably, the reference image is an image captured by a camera when the water storage cavity is filled with high-pressure water and the water is still.

[0013] The present invention also discloses a method for detecting water pressure stability of a water-guided laser water system, which is used in the above-mentioned water pressure stability detection device, and the specific steps thereof include:

[0014] Step 1: Open the high-pressure water system, inject high-pressure water into the water storage cavity, seal the outlet of the water storage cavity, and seal the inlet of the water storage cavity after the high-pressure water fills the water storage cavity. Let the water storage cavity stand until the water layer inside the water storage cavity is stable;

[0015] Step 2: Turn on the light source. The light emitted by the light source is divided into detection light and reference light after passing through the beam splitter. The reference light passes through the first reflector and is then reflected by the beam splitter to the camera lens. The detection light passes through the water storage cavity and reaches the second reflector, and is then reflected to the camera lens. The detection light and the reference light interfere at the camera lens to produce interference fringes.

[0016] Step 3: The interference fringes are collected by a camera and transmitted to a host computer for image processing and then saved as a reference image. The image processing method includes: denoising and filtering;

[0017] Step 4: Open the water inlet and outlet of the water storage cavity to allow the water in the water storage cavity to flow dynamically; collect the interference image changes in real time through the camera and transmit them to the host computer;

[0018] Step 5: The host computer processes the real-time interference image and matches it with the reference image, analyzes the similarity between the two, and thus obtains the water pressure stability of the high-pressure water source in the water-guided laser coupling cavity.

[0019] Preferably, in step 1, the water storage cavity is left standing for no less than 3 minutes.

[0020] Preferably, in step 5, the higher the similarity between the real-time interference image and the reference image, the smaller the change in the optical path difference of the detection light, the smaller the water pressure fluctuation, and the better the stability of the water pressure in the high-pressure water system; conversely, the lower the image similarity, the greater the change in the optical path difference, the greater the water pressure fluctuation, and the worse the stability of the water pressure in the high-pressure water system; this comparison process can be an average fluctuation image over a period of time, or it can be a real-time, periodic image comparison, which can correspond to the processing process and perform a detailed analysis of the impact of water pressure changes on the processing process in different time periods.

[0021] The beneficial effects of the present invention are:

[0022] The present invention splits the light beam into detection light and reference light, and the detection light penetrates the water storage cavity and the high-pressure water body therein, and then performs superposition interference with the reference light. The superposition interference image is compared with the reference image to detect the water pressure stability of the high-pressure water source. The present invention realizes the photoelectric detection of the water pressure stability of the high-pressure water system of the high-precision water-conducting laser, which is helpful to detect whether the water pressure stability of the high-pressure water system meets the requirements of water-conducting laser processing, and can analyze the state of the water jet when the water pressure fluctuates and the state of the water jet when the water pressure is stable through a series of subsequent means. Furthermore, it can be used for subsequent analysis of the impact of the fluctuating state on the processing material and the impact of the stable state on the processing material. Furthermore, the measured fluctuation amount can be used as a variable to analyze the impact of the size of the fluctuation amount on the state of the water jet. It can give full play to the characteristics of the present invention that the detection accuracy is high and the detection can be carried out stably and continuously for a long time. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The present invention is a schematic diagram of a water pressure stability detection device and a detection method of a water-guided laser water system.

[0024] Among them, 1. light source; 2. beam splitter; 3. first reflector; 4. water storage cavity; 5. second reflector; 6. high-pressure water system; 7. camera; 8. host computer. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the relevant technologies in the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] refer to Figure 1 A water pressure stability detection device for a water-guided laser water system comprises: a light source 1, a beam splitter 2, a first reflector 3, a water storage cavity 4, a second reflector 5, a high-pressure water system 6, a camera 7, and a host computer 8. The water storage cavity 4 is a transparent water tank provided with a water inlet and a water outlet. The water inlet of the water storage cavity 4 is connected to the water outlet of the high-pressure water system 6. The high-pressure water system 6 is used to provide a high-pressure water source for the water-guided laser. After passing through the high-pressure water system 6, the high-pressure water source is finally transported to the water-guided laser coupling device through the water storage cavity 4 and coupled with the laser to generate a laser water jet. The emission direction of the light source 1 is toward the beam splitter 2, and the beam splitter 2 splits the incident light L1 emitted by the light source 1 into reflected light L2 and refracted light L3. The reflected light L2 is reflected from the front mirror surface of the beam splitter 2 in a direction symmetrical to the normal line with the incident light L1, and the refracted light L3 is refracted and penetrates the rear mirror surface of the beam splitter 2 and is emitted from the rear mirror surface of the beam splitter 2. At this time, the beam splitter The detection result is better when the angle between the front mirror surface of mirror 2 and the incident direction of incident light L1 is 45°; the reflected light L2 penetrates the water storage cavity 4 and then shines on the second reflector 5 and then reflects to generate reflected light L4, and the reflected light L4 shines on the beam splitter 2 and then refracts to generate refracted light L6 toward the lens of camera 7; the reflected light L2 passes through the transparent box wall of the water storage cavity 4, the water body in the box, and the second reflector 5 and then reflects, and finally enters the lens of camera 7 and is captured by camera 7. At this time, the detection result is better when the water storage cavity 4 and the water body in the box are in the shape of a rectangular parallelepiped; the refracted light L3 shines on the first reflector 3 and then reflects to generate reflected light L5, and the reflected light L5 shines on the beam splitter 2 and then reflects to generate reflected light L7 toward the lens of camera 7; the refracted light L3 is refracted twice and finally enters the lens of camera 7 and is captured by camera 7. At this time, the mirror surface of the first reflector 3 is perpendicular to the incident direction of the refracted light L3, and the detection result is better;

[0027] Camera 7 is an industrial CCD camera, and the data of camera 7 is connected to host computer 8; camera 7 receives two light beams with different optical paths to generate interference phenomenon, and then uploads the image of the interference phenomenon to host computer 8, which analyzes the interference fringe image received by camera 7; host computer 8 is used to process the image uploaded by camera 7 in real time and match it with the reference image, analyze the similarity between the two, so as to obtain the stability of the water pressure in the high-pressure water system 6; host computer 8 compares the interference fringe image with the pre-stored reference image, and determines the change of the optical path difference according to the comparison result, thereby determining the fluctuation of the water pressure in the water storage cavity 4, thereby achieving the purpose of detecting the stability of the water pressure of the high-pressure water source in the laser water jet coupling cavity.

[0028] Furthermore, the light source 1 is a laser light source, and the emitted light of the light source 1 is laser; laser is monochromatic light with better coherence, and it is easier to obtain interference fringes, so the detection result is more accurate.

[0029] Furthermore, the reflected light L4 is emitted through the second reflector 5 and then penetrates the water storage cavity 4 before being irradiated on the beam splitter 2; the reflected light L2 and the reflected light L4 penetrate the water storage cavity 4 and the water therein twice in succession, thereby doubling the sensitivity of the detection effect, and doubling the interference effect of the interference fringe image generated in the camera 7, so that the upper computer 8 has a better effect of determining the optical path difference and a smaller error (the error is halved), thereby improving the accuracy of the water pressure stability detection result.

[0030] Furthermore, the beam splitter 2 and the second reflector 5 are respectively located on two opposite sides of the water storage cavity 4. Although an interference fringe image can be obtained as long as the reflected light L2 and / or L4 passes through the water storage cavity 4 and the water therein at any angle, any incident point and any exit point, the detection effect is better when passing through along two opposite sides.

[0031] Furthermore, the beam splitter 2 and the second reflector 5 are respectively located on the upper and lower sides of the water storage cavity 4; the reflected light L2 and / or L4 penetrates the water storage cavity 4 and the water body in the cavity in the vertical direction and can pass through the entire water layer of the water body for detection, thereby ensuring the stability of the water pressure of the entire water layer in the water storage cavity 4, and further ensuring the overall water pressure stability of the laser water jet coupling cavity.

[0032] Furthermore, the beam splitter 2 is located on the lower side of the water storage cavity 4, and the second reflector 5 is located on the upper side of the water storage cavity 4; the relative upper and lower positions of the beam splitter 2 and the second reflector 5 can be confirmed according to the actual situation at the detection site, but usually when the beam splitter 2 is located on the lower side of the water storage cavity 4, the camera 7 and the beam splitter 2 are located on the same side, which is more conducive to water pressure stability detection and laser water jet processing operations.

[0033] Furthermore, the reference image is an image captured by the camera 7 when the water storage cavity 4 is filled with high-pressure water and the water is still; the water pressure in the water storage cavity 4 is most stable when the water is still under high pressure, so the interference fringe image generated at this time is more suitable for use as a reference reference image.

[0034] The present invention also discloses a method for detecting water pressure stability of a water-guided laser water system, which is used in the above-mentioned water pressure stability detection device, and the specific steps thereof include:

[0035] Step 1: Open the high-pressure water system 6, inject high-pressure water into the water storage cavity 4, close the outlet of the water storage cavity 4, and close the inlet of the water storage cavity 4 after the high-pressure water fills the water storage cavity 4, and let the water storage cavity 4 stand until the water layer inside the water storage cavity 4 is stable;

[0036] Step 2: Turn on the light source 1. The light emitted by the light source 1 is divided into a detection light and a reference light after passing through the beam splitter 2. The reference light passes through the first reflector 3 and is then reflected by the beam splitter 2 to the camera 7 lens. The detection light passes through the water storage cavity 4 and reaches the second reflector 5, and is then reflected to the camera 7 lens. The detection light and the reference light interfere at the camera 7 lens to generate interference fringes.

[0037] Step 3: The interference fringes are collected by a camera 7 and transmitted to a host computer 8 for image processing and then saved as a reference image. The image processing method includes: denoising and filtering;

[0038] Step 4: Open the water inlet and the water outlet of the water storage cavity 4 to allow the water in the water storage cavity 4 to flow dynamically; collect the interference image changes in real time through the camera 7 and transmit them to the host computer 8;

[0039] Step 5: The host computer 8 processes the real-time interference image and matches it with the reference image, and analyzes the similarity between the two, thereby obtaining the water pressure stability of the high-pressure water source in the water-conducting laser coupling cavity.

[0040] Furthermore, in step 1, the water storage cavity 4 is left to stand for no less than 3 minutes.

[0041] Furthermore, in step 5, the higher the similarity between the real-time interference image and the reference image, the smaller the change in the optical path difference of the detection light, the smaller the water pressure fluctuation, and the better the stability of the water pressure in the high-pressure water system 6; conversely, the lower the image similarity, the greater the change in the optical path difference, the greater the water pressure fluctuation, and the worse the stability of the water pressure in the high-pressure water system 6.

[0042] Example

[0043] like Figure 1As shown: the high-pressure water system 6 flows through the pipe to the water storage cavity 4 and then flows out. When the water pressure is stable, the water storage cavity 4 should be in a steady state and can be regarded as a uniform medium; when the water pressure fluctuates, it will cause fluctuations and cavitation in the water layer in the cavity. At this time, the cavity is a non-uniform medium, and when the light beam passes through, different optical path differences will be generated.

[0044] In this embodiment, the light source 1 adopts a laser light source, and the light emitted by it is divided into reference light and detection light after passing through the beam splitter 2. The detection light reaches the second reflector 5 after passing through the water storage cavity 4. The reflected detection light and the reference light interfere with each other at the camera 7, generating interference fringes. The interference fringes are collected and recorded by the camera 7, and then the data is transmitted to the host computer 8 for analysis and processing. When the water pressure fluctuates, it will cause the water layer in the water storage cavity 4 to change, thereby affecting the propagation of the detection light. Since different optical path differences will produce different interference phenomena, the current water pressure stability can be judged by analyzing the interference fringes received by the camera 7.

[0045] The specific detection process is as follows:

[0046] Open the high-pressure water system 6, inject high-pressure water into the water storage cavity 4, close the outlet of the water storage cavity 4, wait until the high-pressure water fills the water storage cavity 4, close the inlet of the water storage cavity 4, and let the water storage cavity stand for 3 minutes to stabilize the water layer inside.

[0047] Turn on the detection light source 1. The light emitted by the light source 1 is divided into detection light and reference light after passing through the beam splitter 2. The reference light passes through the first reflector 3 and is then reflected by the beam splitter 2 to the surface of the camera 7. The detection light passes through the water storage cavity 4 and reaches the second reflector 5, and is then reflected to the surface of the camera 7. The detection light and the reference light interfere on the surface of the camera 7 to generate interference fringes. The interference fringes are collected by the camera 7 and transmitted to the host computer 8 for image processing such as denoising and filtering, and then saved as a reference image.

[0048] The water inlet and outlet of the water storage cavity 4 are opened to allow the water in the water storage system to flow dynamically. The camera 7 collects the interference image changes in real time, and the host computer 8 processes the real-time image and matches it with the reference image to analyze the similarity between the two. The higher the image similarity, the smaller the change in the optical path difference of the detection light and the smaller the water pressure fluctuation.

[0049] In summary, the present invention splits a light beam into a detection light and a reference light, the detection light penetrates the water storage cavity and the high-pressure water body therein, and then performs superposition interference with the reference light, and the superposition interference image is compared with the reference image to detect the water pressure stability of the high-pressure water source. The present invention realizes high-precision photoelectric detection of the water pressure stability of the water-conducting laser high-pressure water system, which is helpful to detect whether the water pressure stability of the high-pressure water system meets the requirements of water-conducting laser processing. The present invention has high detection accuracy and can perform stable and continuous detection for a long time, and has broad application prospects.

[0050] It should be emphasized that the above are only preferred embodiments of the present invention and do not limit the present invention in any form. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A method for detecting water pressure stability of a water-guided laser water system, characterized in that: The water pressure stability detection device used in the detection method comprises: a light source (1), a beam splitter (2), a first reflector (3), a water storage cavity (4), a second reflector (5), a high-pressure water system (6), a camera (7), and a host computer (8); the water storage cavity (4) is a transparent water tank provided with a water inlet and a water outlet; the water inlet of the water storage cavity (4) is connected to the water outlet of the high-pressure water system (6); and the high-pressure water system (6) is used to provide a high-pressure water source for the water-guided laser; The light emitted by the light source (1) is directed toward the beam splitter (2), and the beam splitter (2) splits the incident light L1 emitted by the light source (1) into reflected light L2 and refracted light L3; The reflected light L2 penetrates the water storage cavity (4) and is irradiated on the second reflector (5) and then reflected to generate reflected light L4. The reflected light L4 is irradiated on the beam splitter (2) and then refracted to generate refracted light L6 which is directed toward the lens of the camera (7); The refracted light L3 is irradiated on the first reflector (3) and then reflected to generate reflected light L5, and the reflected light L5 is irradiated on the beam splitter (2) and then reflected to generate reflected light L7 toward the lens of the camera (7); The camera (7) is an industrial CCD camera, and the camera (7) is data-connected to the host computer (8); The host computer (8) is used to process the image uploaded by the camera (7) in real time and match it with the reference image, and analyze the similarity between the two, so as to obtain the stability of the water pressure in the high-pressure water system (6); The specific steps of the detection method include: Step 1: Open the high-pressure water system (6), inject high-pressure water into the water storage cavity (4), close the outlet of the water storage cavity (4), and close the inlet of the water storage cavity (4) after the high-pressure water fills the water storage cavity (4). Let the water storage cavity (4) stand still until the water layer inside the water storage cavity (4) is stable; Step 2: Turn on the light source (1), the light emitted by the light source (1) passes through the beam splitter (2) and is split into detection light and reference light, the reference light passes through the first reflector (3) and is then reflected by the beam splitter (2) to the camera (7) lens; the detection light passes through the water storage cavity (4) and reaches the second reflector (5), and is then reflected to the camera (7) lens; the detection light and the reference light interfere at the camera (7) lens, generating interference fringes; Step 3: The interference fringes are collected by a camera (7) and transmitted to a host computer (8) for image processing and then saved as a reference image. The image processing method includes: denoising and filtering; Step 4: Open the water inlet and the water outlet of the water storage cavity (4) to allow the water in the water storage cavity (4) to flow dynamically; collect the interference image changes in real time through the camera (7) and transmit them to the host computer (8); Step 5: The host computer (8) processes the real-time interference image and matches it with the reference image, and analyzes the similarity between the two, thereby obtaining the water pressure stability of the high-pressure water source in the water-conducting laser coupling cavity.

2. A method for detecting water pressure stability of a water-guided laser water system according to claim 1, characterized in that: The light source (1) is a laser light source, and the light emitted by the light source (1) is laser.

3. The method for detecting water pressure stability of a water-guided laser water system according to claim 1, characterized in that: The reflected light L4 is emitted through the second reflector (5), first penetrates the water storage cavity (4) and then irradiates the beam splitter (2).

4. The method for detecting water pressure stability of a water-guided laser water system according to claim 1, characterized in that: The beam splitter (2) and the second reflector (5) are respectively located on two opposite sides of the water storage cavity (4).

5. A method for detecting water pressure stability of a water-guided laser water system according to claim 4, characterized in that: The beam splitter (2) and the second reflector (5) are respectively located on the upper and lower sides of the water storage cavity (4).

6. A method for detecting water pressure stability of a water-guided laser water system according to claim 5, characterized in that: The beam splitter (2) is located on the lower side of the water storage cavity (4), and the second reflector (5) is located on the upper side of the water storage cavity (4).

7. The method for detecting water pressure stability of a water-guided laser water system according to claim 1, characterized in that: The reference image is an image captured by the camera (7) when the water storage cavity (4) is filled with high-pressure water and the water is still.

8. The method for detecting water pressure stability of a water-guided laser water system according to claim 1, characterized in that: In the step 1, the water storage cavity (4) is left to stand for no less than 3 minutes.

9. The method for detecting water pressure stability of a water-guided laser water system according to claim 1, characterized in that: In step 5, the higher the similarity between the real-time interference image and the reference image, the smaller the change in the optical path difference of the detection light, the smaller the water pressure fluctuation, and the better the stability of the water pressure in the high-pressure water system (6); conversely, the lower the image similarity, the greater the change in the optical path difference, the greater the water pressure fluctuation, and the worse the stability of the water pressure in the high-pressure water system (6).

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