Method for rapidly detecting laser weakening effect by using illuminometer

Abstract

The invention discloses a method for rapidly detecting a laser weakening effect by using an illuminometer, which belongs to the technical field of automobile manufacturing and safety, and is characterized in that a light source is arranged at a position, directly facing a weakening hole, on the back of a part, so that the light direction is consistent with the weakening hole direction, and the illuminometer is mounted at a position, directly facing the weakening hole, on the front of the part. When no part is installed, light directly enters the illuminometer, the illuminometer detects a light intensity signal in real time and transmits the light intensity signal to the control unit, and an illumination value L0 is measured; when a part is installed, after light penetrates through the weakening hole and enters the illuminometer, the illuminometer detects a light intensity signal in real time and transmits the light intensity signal to the control unit, the illuminance value L1 is measured, and whether the weakening hole is qualified or not is judged according to the ratio of L1 to L0. The testing method is high in detection precision, the weakening hole form change can be recognized, detection can be completed in a short time through the multi-point illuminometer layout, and the testing method is suitable for a large-scale production line. The illuminometer is simple in structure and convenient to arrange, the detection process is non-destructive, and the overall detection cost is reduced.

Description

Technical Field

[0001] The invention belongs to the field of automobile manufacturing and safety technology, and specifically is a method for rapidly detecting laser weakening effect by using an illuminometer. Background Art

[0002] When a vehicle has a safety accident, in order to ensure that the passenger side airbag can be deployed smoothly, the car dashboard usually needs to be laser weakened. This treatment generates a microporous structure with a certain contour on the back of the dashboard to reduce the material strength, thereby guiding the airbag to open in the designed direction. Since airbag deployment involves safety performance, the laser weakening process requires accurate and real-time quality monitoring. The number and shape of the weakened holes must meet the design requirements. However, due to the fluctuations in the physical properties of the material and the limitations of the detection accuracy of the laser equipment, the weakened holes often have problems such as insufficient number, too large or too small apertures.

[0003] The commonly used quality control method at present is destructive testing, that is, after cutting the parts, the weakened hole status is observed through a microscope. However, this method has the following shortcomings:

[0004] 1. It is a destructive test, which leads to parts loss and increased costs;

[0005] 2. Only some parts can be inspected, which makes it difficult to fully reflect the process status;

[0006] 3. For materials such as genuine leather and PU leather, cutting will destroy the weakened pore structure, and the complete shape cannot be observed under a microscope.

[0007] CN202223533039 proposes a method for detecting single-layer skeleton through-holes by using a visual camera and a backlight source. However, this technology has a poor detection effect on multi-layer composite materials or materials with low light transmittance because too little light is transmitted and it is difficult for the visual camera to capture it. Summary of the invention

[0008] In order to solve the shortcomings of the existing technology in the detection of multi-layer composite materials and low-light-transmittance materials, the present invention proposes a method for detecting the laser weakening effect using illumination. By detecting trace light-transmittance signals through a high-precision illumination sensor, real-time and accurate weakening effect evaluation can be achieved.

[0009] The technical solution of the present invention is as follows: a method for quickly detecting the laser weakening effect using an illuminometer, comprising the following steps:

[0010] S1: Arrange the light source at the position on the back of the part facing the weakening hole so that the direction of the light is consistent with the direction of the weakening hole;

[0011] S2 Install the sensor on the front of the part facing the weakened hole;

[0012] S3 does not install parts, light enters the sensor, the sensor detects the light intensity signal in real time and transmits it to the control unit to measure the illumination value L0;

[0013] S4 installs parts. After the light passes through the weakened hole and enters the sensor, the sensor detects the light intensity signal in real time and transmits it to the control unit, measures the illumination value L1, and uses the ratio of L1 / L0 to determine whether the weakened hole is qualified.

[0014] Furthermore, in step S1, the light source type is a laser spotlight, an LED lamp, a xenon lamp or a halogen lamp, and the wavelength of the light source is between 250 and 1000 nm.

[0015] Furthermore, the wavelength of the light source is 400-700 nm.

[0016] Furthermore, the wavelength of the light source is 532nm or 650nm.

[0017] Furthermore, in step S2, the diameter of the weakened hole close to the light source is 0.3-2 mm, and the diameter of the weakened hole close to the illuminometer is 0.05-1 mm.

[0018] Furthermore, the diameter of the weakened hole close to the light source is 0.5 mm, and the diameter of the weakened hole close to the illuminometer is 0.2 mm.

[0019] Furthermore, in step S2, the surface material of the part can be PP hard plastic, PVC slush molded surface, TPO vacuum formed surface, PVC / PU / TPO artificial leather, PU sprayed surface, genuine leather, etc. They are opaque or difficult to transmit light materials with a transmittance range of 0% to 2%.

[0020] Furthermore, in step S2, the detection range of the illuminometer is 0.01-40,000 lx, and the responsive wavelength range is 250-1000 nm.

[0021] Furthermore, in step S2, illuminometers are arranged along the weakening track at the same interval, and the distance is 3 cm to 15 cm.

[0022] Further, the distance is 5 cm.

[0023] Furthermore, in step S2, the robot grabs the illuminometer and performs detection along the weakening trajectory.

[0024] Furthermore, in step S2, a light shield is provided outside the illuminometer to form a darkroom structure with the surface of the part, and a circle of reflectors is provided on the inner wall of the light shield.

[0025] Furthermore, in step S4, if the ratio of L1 / L0 is between 0.5% and 5%, the part is qualified.

[0026] The beneficial effects of the present invention are:

[0027] High sensitivity: The illumination sensor is sensitive to trace amounts of light and can detect light signals that cannot be captured by the human eye or camera. It has high detection accuracy and can identify changes in the morphology of weakened holes.

[0028] Fast and efficient: Multi-point sensor layout can complete detection in a short time, suitable for high-volume production lines.

[0029] Low cost: The sensor has a simple structure, is easy to arrange, and the detection process is non-destructive, which reduces the overall detection cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Place a footprint for the part.

[0031] Figure 2 Schematic diagram of the weakening hole and the light transmitting microhole.

[0032] Figure 3 A schematic diagram of the instrument panel.

[0033] Figure 4 This is a test schematic.

[0034] Figure 5 Diagram of the optical path inside the sensor.

[0035] In the figure:

[0036] 1 skeleton, 2 softening layer, 3 epidermis, 4 front of part, 5 back of part, 6 light source, 7 sensor, 8 weakening hole, 9 incident light, 10 outgoing light, 11 instrument panel, 12 light-transmitting micropores, 13 sealing strip, 14 reflector, 15 vertical outgoing light, 16 inclined outgoing light. DETAILED DESCRIPTION

[0037] It should be noted that in the description of the present invention, the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", "clockwise", "counterclockwise", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction.

[0038] In the present invention, unless otherwise clearly specified and limited, the terms "set", "install", "connect", "connect" and the like should be understood in a broad sense. For example, "fixed" can be a fixed connection, a detachable connection, or an integral connection; the connection can be a mechanical connection or an electrical connection; the connection can be a direct connection or an indirect connection through an intermediate medium, and can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] The weakened hole 8 passes through the skeleton 1, the softened layer 2 and the epidermis 3 in sequence to form an instrument panel 11, which is what we call a part. During the test, the front side 4 of the part faces the sensor 7, and the part back 5 is placed toward the light source 6. After the incident light 9 passes through the weakened hole 8, the outgoing light 10 enters the sensor 7. The front end of the epidermis 3 has a light-transmitting microhole 12 arranged in the same position as the weakened hole 8.

[0040] Parallel sealing strips are provided on both sides of the sensor 7, and a reflector 14 is pasted on the sealing strip 13 to facilitate light focusing.

[0041] Set the light source: Arrange a high-brightness light source on the back of the part facing the weakened hole so that the direction of the light is consistent with the direction of the weakened hole.

[0042] Arrange illumination sensor: Install a high-precision light intensity sensor on the front of the part facing the weakened hole. To improve detection accuracy, add a light shield to the outside of the sensor to form a darkroom structure with the surface of the part.

[0043] Signal detection and analysis: When light passes through the weakened hole and enters the sensor, the sensor detects the light intensity signal in real time and transmits it to the control unit. The control unit determines whether the weakened hole is qualified based on the signal standard range determined by the experiment.

[0044] Multi-point detection: A light intensity sensor is arranged at a certain distance along the weakening track, and segmented detection is achieved through the coordinated work of multiple sensors.

[0045] Relative value control: In addition to the absolute detection method, relative value detection can also be performed. The specific method is: remove the parts, connect the light source and the sensor directly (to ensure sealing to prevent light leakage), measure the illumination value L0, then install the parts, measure the illumination value L1 again, and use the ratio of L1 / L2 as a reference for control. The typical L1 / L2 is 0.5% to 5%.

[0046] The above is only a specific implementation of the present invention, but the protection scope of the present invention is not limited thereto. Any modification, equivalent replacement and improvement made by any person skilled in the art within the technical scope disclosed by the present invention and within the spirit and principle of the present invention shall be covered within the protection scope of the present invention. At the same time, the contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0047] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

Claims

1. A method for quickly detecting laser weakening effect using an illuminometer, characterized in that: The following steps are involved: S1: Arrange the light source at the position on the back of the part facing the weakening hole so that the direction of the light is consistent with the direction of the weakening hole; S2 Install the sensor on the front of the part facing the weakened hole; S3 does not install parts, light directly enters the sensor, the sensor detects the light intensity signal in real time and transmits it to the control unit to measure the illumination value L0; S4 installs parts. After the light passes through the weakened hole and enters the sensor, the sensor detects the light intensity signal in real time and transmits it to the control unit, measures the illumination value L1, and uses the ratio of L1 / L0 to determine whether the weakened hole is qualified.

2. The method for quickly detecting laser weakening effect using an illuminometer according to claim 1, characterized in that: In step S1, the light source type is a laser spotlight, an LED lamp, a xenon lamp or a halogen lamp, and the wavelength of the light source is between 250 and 1000 nm.

3. The method for quickly detecting laser weakening effect using an illuminometer according to claim 2, characterized in that: The wavelength of the light source is 400~700nm.

4. The method for quickly detecting laser weakening effect using an illuminometer according to claim 1, characterized in that: In step S2, the diameter of the weakened hole close to the light source is 0.3-2 mm, and the diameter of the weakened hole close to the illuminometer is 0.05-1 mm.

5. The method for quickly detecting laser weakening effect using an illuminometer according to claim 4, characterized in that: The diameter of the weakened hole close to the light source is 0.5 mm, and the diameter of the weakened hole close to the illuminometer is 0.2 mm.

6. The method for quickly detecting laser weakening effect using an illuminometer according to claim 1, characterized in that: In step S2, the surface material of the part can be PP hard plastic, PVC slush surface, TPO vacuum formed surface, PVC / PU / TPO artificial leather, PU spray surface, genuine leather, all of which are opaque or difficult to transmit light materials, with a transmittance range of 0% to 2%.

7. The method for rapidly detecting laser weakening effect using an illuminometer according to claim 1, characterized in that: In step S2, the detection range of the illuminometer is 0.01-40000 lx, and the response wavelength range is 250-1000 nm.

8. The method for rapidly detecting laser weakening effect using an illuminometer according to claim 1, characterized in that: In step S2, illuminometers are arranged along the weakening track at intervals of 3 cm to 15 cm.

9. The method for quickly detecting laser weakening effect using an illuminometer according to claim 1, characterized in that: In step S2, a light shield is provided outside the illuminometer to form a darkroom structure with the surface of the part, and a circle of reflectors is provided on the inner wall of the light shield.

10. The method for quickly detecting laser weakening effect using an illuminometer according to claim 1, characterized in that: In step S4, if the ratio of L1 / L0 is between 0.5% and 5%, the part is qualified.

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