CN116893178B - LED lamp panel welding quality detection method and system - Google Patents

LED lamp panel welding quality detection method and system Download PDF

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CN116893178B
CN116893178B CN202311166315.9A CN202311166315A CN116893178B CN 116893178 B CN116893178 B CN 116893178B CN 202311166315 A CN202311166315 A CN 202311166315A CN 116893178 B CN116893178 B CN 116893178B
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solder
welding
information
tin solder
plate
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CN116893178A (en
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孙慧丽
于海洋
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Nantong Sax Electronics Co ltd
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Nantong Sax Electronics Co ltd
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/84—Systems specially adapted for particular applications
    • G01N21/88—Investigating the presence of flaws or contamination
    • G01N21/8851—Scan or image signal processing specially adapted therefor, e.g. for scan signal adjustment, for detecting different kinds of defects, for compensating for structures, markings, edges
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B11/00—Measuring arrangements characterised by the use of optical techniques
    • G01B11/002—Measuring arrangements characterised by the use of optical techniques for measuring two or more coordinates
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L5/00—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N25/00—Investigating or analyzing materials by the use of thermal means
    • G01N25/72—Investigating presence of flaws
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    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T7/00—Image analysis
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    • G06T7/0004—Industrial image inspection
    • G06T7/001—Industrial image inspection using an image reference approach
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    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T7/00—Image analysis
    • G06T7/10—Segmentation; Edge detection
    • G06T7/13—Edge detection
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T7/00—Image analysis
    • G06T7/60—Analysis of geometric attributes
    • G06T7/62—Analysis of geometric attributes of area, perimeter, diameter or volume
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T2207/00—Indexing scheme for image analysis or image enhancement
    • G06T2207/30—Subject of image; Context of image processing
    • G06T2207/30108—Industrial image inspection
    • G06T2207/30152—Solder

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Abstract

The application discloses a method and a system for detecting welding quality of an LED lamp panel, wherein the method comprises the steps of detecting the position, the type and the size of a welding pad; the method comprises the steps of obtaining a temperature sensing unit to detect the surface temperature of a welding plate, obtaining a positioning unit to position a position with higher temperature on the welding plate, namely a tin solder position, and comparing the tin solder position with a bonding pad position; if the tin solder on the welding plate exceeds 10% of the welding plate area or the tin solder does not cover the welding plate area by more than 10%, the quality of the tin solder is unqualified; calculating the volume of the tin solder based on the triple integral calculation model to analyze the shape of the tin solder; acquiring image amplification information of a welding position and analyzing the contact surface and the contact position of the LED pins and the tin solder; judging the stress condition of the tin solder based on the contact surface information and the contact position information; obtaining a standard shape of the extruded tin solder based on the extrusion analysis model; and reconstructing the tin solder based on an algorithm to obtain welding spot reconstruction information, and if the welding spot reconstruction shape is inconsistent with the standard shape, failing to detect the welding spot quality. The application has the effect of improving the welding quality detection accuracy of the LED lamp panel.

Description

LED lamp panel welding quality detection method and system
Technical Field
The application relates to the technical field of welding quality detection, in particular to a method and a system for detecting welding quality of an LED lamp panel.
Background
Currently, an LED, i.e., a light emitting diode, is a solid semiconductor material chip capable of converting electrical energy into visible light. The LLED light source has the advantages of low-voltage power supply, low energy consumption, strong applicability, high stability, short response time, no pollution to the environment, multicolor light emission and the like. LEDs are increasingly used in industry and consumer electronics, and welding is one of the most commonly used fixing methods in the application process of LED elements, so it is necessary to detect the welding quality of LED lamp panels.
In the related art, in the welding detection of an LED lamp panel, a visual inspection method is the most basic and common detection method, and whether a welding spot is smooth and flat or not and whether the welding spot volume is proper or not is detected by observing the appearance of a welding part through human eyes; detecting whether the connection condition between the bonding pad and the welding spot is good or not and whether the metal gasket around the bonding pad is damaged or not; detecting whether defects such as cold welding, short circuit, open circuit and the like exist at the welding position.
Aiming at the related technology, for some special welding defects, such as the problems of cracks or air bubble inclusion in the welding spot, and the like, the visual inspection method is difficult to detect, the LED lamp panel with the cracks or air bubble inclusion in the welding spot is regarded as a qualified product, the accuracy of welding quality detection of the LED lamp panel is not high, and the labor cost for manually and visually detecting the welding quality of the LED lamp panel is high, so that improvement exists.
Disclosure of Invention
In order to improve accuracy of welding quality detection of an LED lamp panel, the application provides a method and a system for detecting welding quality of an LED lamp panel.
In a first aspect, the present application provides a method for detecting welding quality of an LED lamp panel, which adopts the following technical scheme:
a welding quality detection method for an LED lamp panel comprises the following steps:
acquiring a welding plate and a three-dimensional rectangular coordinate system, establishing data connection, detecting the position and the type of a welding plate on the welding plate, and respectively detecting the size of the welding plate;
the method comprises the steps of obtaining the surface temperature of a soldering plate after brushing tin solder by a temperature sensing unit, obtaining the position of the soldering plate, namely the tin solder position on the soldering plate, of a positioning unit, and comparing and analyzing the tin solder position with the position of a bonding pad;
if the area of the solder plate, which exceeds the solder pad, exceeds 10% of the corresponding solder pad area or the area of the solder pad, which is not covered by the solder pad, exceeds 10% of the corresponding solder pad area, the quality of the solder brushing in the corresponding solder pad area is not qualified, otherwise, the quality of the solder brushing in the corresponding solder pad area is qualified;
obtaining boundary coordinates of the tin solder on each bonding pad of the welding plate based on a three-dimensional rectangular coordinate system, calculating the volume of the tin solder on each bonding pad based on a triple integral calculation model, and analyzing the shape of the tin solder on the welding plate;
Acquiring and amplifying the image information of the welding position based on the image pick-up unit to obtain the amplified information of the welding position, analyzing the contact surface and the contact position of the LED pins and the tin solder based on the amplified information of the welding position, and displaying the contact surface and the contact position on a three-dimensional rectangular coordinate system;
judging the pressure of the LED pins on the tin solder based on the contact surface information and the contact position information of the LED pins and the tin solder, and further judging the stress condition of the tin solder;
obtaining the shape of the tin solder, obtaining the standard shape of the extruded tin solder based on an extrusion analysis model according to the stress condition of the tin solder, and storing the standard shape information;
and reconstructing tin solder on the welding plate by adopting an algorithm based on the image amplification information of the welding position to obtain welding spot reconstruction information, comparing the welding spot reconstruction information with standard shape information, if the comparison result is consistent, detecting the quality of the welding spot to be qualified, and if the comparison result is inconsistent, detecting the quality of the welding spot to be unqualified.
Preferably, a welding plate and a three-dimensional rectangular coordinate system are obtained, and data connection between the welding plate and the three-dimensional rectangular coordinate system is established;
the welding plate is corresponding to the three-dimensional rectangular coordinate system, the vertex of the welding plate is corresponding to the origin of the three-dimensional rectangular coordinate system, the plane of the welding component of the welding plate is corresponding to the x-y plane of the three-dimensional rectangular coordinate system, and the two adjacent side lengths connected with the vertex of the corresponding origin of the three-dimensional rectangular coordinate system on the welding plate are respectively corresponding to the x-axis and the y-axis of the three-dimensional rectangular coordinate system;
Detecting the position of each bonding pad on the bonding pad, displaying the corresponding position in a three-dimensional rectangular coordinate system and storing;
and detecting the types of bonding pads with different sizes on the bonding pad, and respectively detecting and storing the size data of the bonding pads with different types.
Preferably, a temperature sensing unit is obtained and data connection between the temperature sensing unit and the welding plate is established;
detecting the surface temperature of the welding plate after the tin-soldering operation is performed on the welding plate based on the temperature sensing unit;
comparing the temperature value of each position on the welding plate with a standard temperature threshold preset in the temperature sensing unit;
acquiring a positioning unit and establishing data connection between the positioning unit and the temperature sensing unit and between the positioning unit and the welding plate respectively;
the positioning unit is used for positioning the position of the temperature value on the welding plate exceeding the standard temperature threshold, namely the position of the tin solder on the welding plate, and displaying the position in a three-dimensional rectangular coordinate system;
and comparing the solder position on the welding plate with the welding plate position in the three-dimensional rectangular coordinate system, and analyzing the corresponding conditions of the welding plate position and the solder position on the welding plate.
Preferably, the position of tin solder on the welding plate is obtained, and the position data is stored;
Judging whether the tin solder position area on the welding plate exceeds the welding plate position area;
if the tin solder position area on the welding plate exceeds the welding plate position area, judging the percentage of the welding plate position area exceeding the welding plate to the welding plate position area;
if the position area of the tin solder on the welding plate exceeds the position area of the welding plate by more than 10 percent, the position area of the tin solder on the welding plate and the position area of the corresponding welding plate are unqualified during welding;
if the tin solder position area on the bonding pad does not exceed, namely, does not completely cover the bonding pad position area, judging the percentage of the position area of the bonding pad, which is not covered by the tin solder, on the bonding pad to the bonding pad position area;
if the position area of the solder plate, which is not covered by the solder, is more than 10% of the position area of the solder plate, which is not covered by the solder, is unqualified with the corresponding position area of the solder plate during welding;
and if the uncovered area and the exceeding area of the tin solder on the welding plate are not more than 10% of the welding plate area, the tin solder position area on the welding plate and the corresponding welding plate position area are qualified during welding.
Preferably, the coordinate position of the tin solder on the welding plate on the three-dimensional rectangular coordinate system is obtained and coordinate position data are stored;
acquiring and storing a triple integral calculation model, wherein the triple integral calculation model is based on calculating the volume of the irregular object;
Establishing data connection between a triple integral calculation model and a three-dimensional rectangular coordinate system;
the triple integral calculation model obtains boundary coordinate data of solder materials on a solder plate;
calculating the volume of the tin solder on the welding plate based on boundary coordinate data information of the tin solder on the welding plate to obtain a plurality of tin solder volume information;
measuring the contact area of each tin solder on the soldering plate and the soldering pad and the height of each tin solder, and acquiring a plurality of tin solder contact area information and tin solder height information;
and analyzing the shape of the solder before the component is placed after the solder is brushed on the solder plate based on the plurality of pieces of solder volume information, the plurality of pieces of solder contact area information and the plurality of pieces of solder height information, thereby obtaining a plurality of pieces of solder shape information.
Preferably, acquiring an image pickup unit and an amplifying unit and establishing data connection;
shooting the welding position based on the image pick-up unit to obtain welding position image information and storing the welding position image information;
acquiring welding position image information, amplifying the welding position image information based on an amplifying unit, acquiring and storing welding position image amplifying information;
acquiring an LED model and acquiring LED pin size data based on the LED model;
Acquiring LED pin position information based on the welding position image amplification information;
establishing data connection between the amplifying unit and the three-dimensional rectangular coordinate system, displaying the positions of the LED pins in the three-dimensional rectangular coordinate system, and storing the positions;
and analyzing the contact surface and the contact position of the LED pins and the tin solder based on the image amplification information of the welding part, displaying the contact surface information and the contact position information on a three-dimensional rectangular coordinate system, and storing the contact surface information and the contact position information.
Preferably, contact surface information and contact position information of the LED pins and the tin solder are obtained and stored, wherein the contact surface information comprises contact surface type information and contact surface number information, and the contact position information comprises contact edge information and contact area information;
judging the number of pressures generated by the LED pins on the tin solder when the LED pins are in contact with the tin solder, namely the number of stressed materials of the tin solder, based on the number information of the contact surfaces of the LED pins and the tin solder, so as to obtain stressed number information;
judging the pressure direction of the LED pin to the tin solder when the LED pin contacts the tin solder based on the contact surface type information of the LED pin and the tin solder, wherein the opposite direction of the pressure direction is the stress direction of the tin solder, and if the tin solder contacts a plurality of surfaces of the LED pin, obtaining a plurality of stress direction information;
Judging the stress point position of the tin solder based on the contact edge information of the LED pins and the tin solder, wherein the central position of the contact surface of the tin solder and one surface of the LED pins is the stress point position of the tin solder, and if the tin solder contacts with a plurality of surfaces of the LED pins, obtaining a plurality of stress point position information;
and judging the stress of the tin solder based on the contact area information of the LED pins and the tin solder, wherein the stress is larger as the contact area of the tin solder and one surface of the LED pins is larger, and if the tin solder contacts with a plurality of surfaces of the LED pins, a plurality of stress point size information is obtained.
Preferably, tin solder shape information and tin solder stress condition information are obtained and stored, wherein the tin solder stress condition information comprises stress number information, a plurality of stress direction information, a plurality of stress point position information and a plurality of stress point size information;
acquiring an extrusion analysis model and establishing signal connection;
and inputting the tin solder shape information, the stress number information, the stress direction information, the stress point position information and the stress point size information of each tin solder on the welding plate into an extrusion analysis model to respectively obtain standard shapes which are generated after the tin solders are extruded and store the tin solder standard shape information.
Preferably, acquiring and storing the image amplification information of the welding position;
three-dimensional reconstruction is carried out on the image amplification information of the welding positions based on an algorithm, and welding spot reconstruction information of the welding positions of the LED pins and the tin solder on the welding plate is restored;
acquiring a three-dimensional model database and storing reconstruction information data of a plurality of welding spots;
acquiring a comparison unit and establishing data connection between the comparison unit and a three-dimensional model database and between the comparison unit and an extrusion analysis model;
comparing the standard shape information of the tin solder with the reconstruction information of the welding spots at the corresponding positions, and judging whether quality problems occur during welding of the welding spots;
if the welding spot reconstruction information at the welding spot is consistent with the corresponding tin solder standard shape information, the welding quality problem at the welding spot is avoided; if the reconstruction information of the welding spot at the welding spot is inconsistent with the standard shape information of the corresponding tin solder, the welding quality problem occurs at the welding spot;
and marking all welding spots with welding quality problems on the welding plate and displaying the welding spots in a three-dimensional rectangular coordinate system.
In a second aspect, the application provides a welding quality detection system for an LED lamp panel, which adopts the following technical scheme:
the welding quality detection system of the LED lamp panel comprises a welding plate, a welding plate detection unit and a three-dimensional rectangular coordinate system, wherein the welding plate comprises a plurality of welding plates, and the welding plate detection unit is used for respectively detecting the welding plate positions, the welding plate types and the welding plate sizes of the welding plates and outputting welding plate position signals, welding plate type signals and welding plate size signals;
The welding plate and the welding plate detection unit are both in signal connection with a three-dimensional rectangular coordinate system, and the three-dimensional rectangular coordinate system is used for receiving the welding plate position signals, the welding plate type signals and the welding plate size signals and displaying the welding plate position signals and the welding plate size signals at the corresponding positions of the welding plate on the three-dimensional rectangular coordinate system;
the corresponding position detection module comprises a temperature sensing unit, a temperature comparison unit and a positioning unit, wherein the temperature sensing unit and the positioning unit are arranged on the welding plate, and the temperature sensing unit is used for detecting the temperature on the welding plate after the operation of brushing tin solder and outputting a temperature signal;
the temperature comparison unit is in signal connection with the temperature sensing unit, a standard temperature threshold value is preset in the temperature comparison unit, the temperature comparison unit is used for comparing the temperature signal with the standard temperature threshold value signal after receiving the temperature signal, and if the temperature signal exceeds the standard temperature threshold value signal, a high temperature signal is output;
the positioning unit is configured to be in signal connection with the temperature comparison unit, the output end of the positioning unit is in signal connection with the input end of the three-dimensional rectangular coordinate system, and the positioning unit is used for receiving the high-temperature signal, positioning the region with the excessively high temperature on the welding plate, outputting a tin solder position signal and marking the positioning region in the three-dimensional rectangular coordinate system;
The corresponding position judging module is configured to be in signal connection with the positioning unit and the three-dimensional rectangular coordinate system, the corresponding position judging module receives the tin solder position signal and the bonding pad position signal to analyze the corresponding degree of the tin solder position area and the bonding pad position area, and when the area of the bonding pad uncovered by the tin solder on the bonding pad exceeds 10% of the corresponding bonding pad area or the area exceeding the bonding pad exceeds 10% of the corresponding bonding pad area, the tin solder on the bonding pad and the corresponding bonding pad area do not accord with the corresponding disqualified signal of the output position;
the solder shape analysis module is configured to be in signal connection with the positioning unit, and is used for receiving the signal of the solder position area, calculating the coordinate position data of the solder on a three-dimensional rectangular coordinate system based on a triple integral calculation model, calculating the volume of each solder on the solder plate, and analyzing the solder shape information and outputting a solder shape signal after measuring the contact area information and the height information of the solder;
the contact analysis module comprises a camera unit and an amplifying unit, wherein the camera unit is in signal connection with the amplifying unit, the camera unit is used for shooting image information of a welding position on a welding plate and outputting the image signal of the welding position to the amplifying unit, and the amplifying unit is used for receiving the image signal of the welding position to amplify and then outputting an image amplified signal of the welding position, wherein the image amplified signal of the welding position comprises an LED pin and tin solder contact surface signal and a contact position signal;
The stress analysis module is configured to be in signal connection with the amplifying unit and is used for receiving the contact surface signal and the contact position signal, judging the pressure of the LED pins on the tin solder, analyzing and processing the stress condition of the tin solder and then outputting a stress signal of the tin solder;
the standard shape analysis module is configured to be in signal connection with the stress analysis module, and is used for receiving the tin solder stress signal, judging and analyzing the standard shape which the tin solder should form under the current stress condition based on the extrusion analysis model according to the tin solder stress condition and outputting the tin solder standard shape signal; the method comprises the steps of,
the reconstruction judging module is configured to be in signal connection with the amplifying unit and the standard shape analyzing module, and is used for receiving the image amplifying signal of the welding position, then carrying out three-dimensional reconstruction on the actual extrusion shape of the tin solder on the welding plate, outputting a welding spot reconstruction signal, comparing the welding spot reconstruction signal with the standard shape signal of the tin solder, and when the welding spot reconstruction signal is consistent with the standard shape signal of the tin solder, the welding quality of the welding spot is normal, and when the welding spot reconstruction signal is inconsistent with the standard shape signal of the tin solder, the welding quality of the welding spot is abnormal.
In summary, the present application includes at least one of the following beneficial technical effects:
obtaining boundary coordinates of each tin solder on a welding plate through a three-dimensional rectangular coordinate system, calculating the volume of each tin solder based on a triple integral calculation model, analyzing the shape of each tin solder, shooting and amplifying a welding position to obtain amplified image information of the welding position, analyzing the contact surface and the contact position of an LED pin and the tin solder based on the amplified image information of the welding position so as to judge the stress condition of the tin solder, analyzing the extruded shape of the tin solder based on the extrusion analysis model to obtain standard shape information, reducing the extruded shape of the tin solder at the welding position based on a three-dimensional reconstruction algorithm to obtain welding spot reconstruction information, comparing the welding spot reconstruction information with the standard shape information, if the welding spot reconstruction information is consistent with the standard shape information, judging that the welding quality of the welding spot of the LED lamp panel is qualified, if the welding spot welding quality of the welding spot of the LED lamp panel is not consistent, and improving the accuracy of welding quality detection of the LED lamp panel;
detecting the surface temperature of the welding plate after the welding plate is subjected to tin soldering operation by means of the temperature sensing unit, comparing the detected temperature value with a preset standard temperature threshold value on the basis of the temperature comparison unit, positioning the area, namely a tin soldering position area, of which the detected temperature value exceeds the standard temperature threshold value on the basis of the positioning unit, analyzing the corresponding degree of the tin soldering position area and a bonding pad position area, and if the uncovered area and the exceeding area of the tin soldering on the welding plate are not more than 10% of the bonding pad area, judging that the welding quality of the tin soldering position area and the corresponding bonding pad position area on the welding plate is qualified during welding, otherwise, judging that the welding quality is unqualified, and further improving the accuracy of the welding quality detection of the LED lamp plate.
Drawings
Fig. 1 is a flow chart of a method for detecting welding quality of an LED lamp panel according to the present embodiment;
fig. 2 is a schematic flow chart mainly showing step S1 in this embodiment;
fig. 3 is a schematic flow chart mainly showing step S2 in this embodiment;
fig. 4 is a schematic flow chart mainly showing step S3 in this embodiment;
fig. 5 is a schematic flow chart mainly showing step S4 in this embodiment;
fig. 6 is a schematic flow chart mainly showing step S5 in this embodiment;
fig. 7 is a schematic flow chart mainly showing step S6 in this embodiment;
fig. 8 is a schematic flow chart mainly showing step S7 in this embodiment;
fig. 9 is a schematic flow chart mainly showing step S8 in this embodiment;
fig. 10 is a schematic block diagram of a system for detecting welding quality of an LED lamp panel according to the present embodiment.
Reference numerals: 1. a pad detection module; 11. welding a plate; 12. a pad detection unit; 13. a three-dimensional rectangular coordinate system; 2. a corresponding position detection module; 21. a temperature sensing unit; 22. a temperature comparing unit; 23. a positioning unit; 3. a corresponding position judging module; 4. a tin solder shape analysis module; 5. a contact analysis module; 51. an image pickup unit; 52. an amplifying unit; 6. a stress analysis module; 7. a standard shape analysis module; 8. and a reconstruction judging module.
Detailed Description
The present application is described in further detail below with reference to the accompanying drawings.
The embodiment of the application discloses a welding quality detection method for an LED lamp panel.
A welding quality detection method for an LED lamp panel comprises the following steps:
referring to fig. 1 and 2, step S1, the bonding pad 11 and the three-dimensional rectangular coordinate system 13 are acquired and data connection between the bonding pad 11 and the three-dimensional rectangular coordinate system 13 is established, and the position of each bonding pad on the bonding pad 11 and the type of the bonding pad are detected and the sizes of bonding pads of different types are detected respectively. The step S1 specifically comprises the following steps:
step S11, the welding plate 11 and the three-dimensional rectangular coordinate system 13 are obtained, and data connection between the welding plate 11 and the three-dimensional rectangular coordinate system 13 is established.
In step S12, the solder board 11 is disposed corresponding to the three-dimensional rectangular coordinate system 13, and one of the vertices of the surface of the solder board 11 on which the solder component is soldered corresponds to the origin of the three-dimensional rectangular coordinate system 13. The plane of the welding component of the welding plate 11 corresponds to the x-y plane of the three-dimensional rectangular coordinate system 13, wherein two adjacent side lengths connected with the vertex of the corresponding three-dimensional rectangular coordinate system 13 on the welding plate 11 correspond to the x-axis and the y-axis of the three-dimensional rectangular coordinate system 13 respectively, and the side length passing through the origin and perpendicular to the x-y plane corresponds to the negative direction of the z-axis.
Step S13, detecting the position of each bonding pad on the bonding pad 11, displaying the corresponding position of each bonding pad position in the three-dimensional rectangular coordinate system 13, and storing.
Step S14, detecting the bonding pads with different sizes on the bonding pad 11, judging the types of the bonding pads with different sizes, respectively detecting the size data of the bonding pads with different types, and storing the size data.
Referring to fig. 1 and 3, step S2 is to acquire a temperature sensing unit 21 and detect the surface temperature of the solder plate 11 after brushing the solder based on the temperature sensing unit 21, acquire a positioning unit 23 and position the solder position, which is the position where the temperature value on the solder plate 11 exceeds the standard temperature threshold, based on the positioning unit 23, compare the solder position with the pad position, and analyze the correspondence between the pad position and the solder position on the solder plate 11. The step S2 specifically comprises the following steps:
in step S21, the temperature sensing unit 21 is obtained and a data connection between the temperature sensing unit 21 and the solder board 11 is established, wherein a standard temperature threshold is preset in the temperature sensing unit 21.
In step S22, the surface temperature of the solder plate 11 after the solder plate 11 is subjected to the soldering operation is detected based on the temperature sensing unit 21.
In step S23, the temperature values of the positions on the solder board 11 are compared with the preset standard temperature threshold value in the temperature sensing unit 21, and if the detected temperature value exceeds the standard temperature threshold value, the solder board 11 performs the operation of brushing tin solder.
In step S24, the positioning unit 23 is acquired, and data connection between the positioning unit 23 and the temperature sensing unit 21 and the solder board 11 is established.
In step S25, the positioning unit 23 positions the position on the solder plate 11 where the temperature value exceeds the standard temperature threshold, and the detected temperature value on the solder plate 11 exceeds the standard temperature threshold, that is, the position of the solder on the solder plate 11, and displays the position of the solder in coordinates in the three-dimensional rectangular coordinate system 13.
In step S26, the positions of the solder on the solder plate 11 and the positions of the pads in the three-dimensional rectangular coordinate system 13 are compared, and the positions of the pads on the solder plate 11 and the positions of the solder on the solder plate 11 are analyzed.
In operation, the temperature of the surface of the solder plate 11 increases due to the temperature of the solder during the soldering process, and the temperature of the solder plate 11 is detected by the temperature sensing unit 21 to determine the location area of the solder on the solder plate 11. In the case of soldering, the temperature of the peripheral area of the solder on the solder plate 11 is also raised by the high temperature of the solder, so that the standard temperature threshold should be higher than the original temperature of the solder plate 11 before soldering.
Referring to fig. 1 and 4, in step S3, if the area of the solder plate 11 where the solder exceeds the pad exceeds 10% of the corresponding pad area or the area of the solder uncovered by the pad exceeds 10% of the corresponding pad area, the quality of the solder plate 11 where the solder does not exceed the pad area is not qualified, and if the area of the solder plate 11 where the solder uncovered by the solder does not exceed 10% of the pad area until the area of the solder exceeds 10% of the pad area, the quality of the solder plate 11 where the solder does not exceed the pad area is qualified. The step S3 specifically comprises the following steps:
step S31, the solder position and the pad position on the solder plate 11 are acquired and the solder position data and the pad position data are stored.
In step S32, it is determined whether or not the solder position area on the solder plate 11 exceeds the corresponding pad position area.
In step S33, if the solder position area on the solder plate 11 exceeds the corresponding pad position area, the percentage of the solder position area on the solder plate 11 exceeding the corresponding pad to the corresponding pad position area is analyzed and determined.
In step S34, if the solder on the soldering plate 11 exceeds the position area of the corresponding pad by more than 10% of the position area of the corresponding pad, the quality of the solder brushing between the position area of the solder on the soldering plate 11 and the position area of the corresponding pad is not acceptable during soldering.
In step S35, if the solder position area on the pad does not exceed and does not cover the corresponding pad position area, the percentage of the solder position area on the solder plate 11 that does not cover the corresponding pad to the corresponding pad position area is analyzed and determined.
In step S36, if the position area of the solder plate 11 where the solder does not cover the corresponding pad is 10% or more of the position area of the corresponding pad, the quality of the solder brushing between the position area of the solder plate 11 and the position area of the corresponding pad is not acceptable during soldering.
In step S37, if the uncovered area of the solder on the solder board 11 does not exceed 10% of the pad area until the uncovered area of the solder exceeds 10% of the pad area, the quality of the solder brushed on the solder board 11 corresponding to the pad position area is qualified during soldering.
During operation, during operation of brushing tin solder, the tin solder position on the welding plate 11 corresponds to the corresponding welding disc position, wherein the tin solder area is slightly larger than the corresponding welding disc area or the tin solder area is slightly smaller than the welding disc area, the corresponding conditions of the tin solder position on the welding plate 11 and the welding disc position are analyzed, if the corresponding conditions are not met, the situation that the content of the tin solder on the welding plate 11 is too high and too good and the welding quality is influenced by the fact that the tin solder is not corresponding to the welding disc position in the subsequent step is difficult to grasp, the conditions that insufficient welding spot is in unstable welding failure, the deformation or damage of the welding disc is offset in the tin solder position and the fixing and electrical connection quality of components are influenced can occur, the quality of brushing tin solder during welding is judged when the corresponding degree of the tin solder on the welding plate 11 is analyzed, and the problem of welding quality during brushing tin solder is greatly reduced.
Referring to fig. 1 and 5, step S4 obtains boundary coordinates of the solder on each pad of the solder plate 11 based on the three-dimensional rectangular coordinate system 13, calculates the volume of the solder on each pad based on the triple integral calculation model, and analyzes the shape of the solder on the solder plate 11. The step S4 specifically comprises the following steps:
in step S41, the coordinate position of the solder on the solder plate 11 on the three-dimensional rectangular coordinate system 13 is obtained and the coordinate position data of the solder is stored.
Step S42 obtains and stores a triple integral calculation model, wherein the triple integral calculation model is based on calculating the irregular object volume.
In step S43, a data connection between the triple integral calculation model and the three-dimensional rectangular coordinate system 13 is established.
Step S44, the triple integral calculation model acquires boundary coordinate data of the solder paste of the solder plate 11 on the three-dimensional rectangular coordinate system 13.
Step S45, calculating the volume of each solder on the solder plate 11 according to the triple integral calculation model based on the boundary coordinate data information of the solder on the solder plate 11, so as to obtain a plurality of pieces of solder volume information.
In step S46, the contact area between each solder and the pad on the solder plate 11 and the height of each solder on the pad are measured, and a plurality of pieces of solder contact area information and solder height information are obtained.
In step S47, the shape of the solder before the component is placed on the solder plate 11 after the soldering is performed on the basis of the plurality of solder volume information, the plurality of solder contact area information, and the plurality of solder height information, and a plurality of solder shape information is obtained.
In application, the triple integral can be used for calculating the volume of an irregular object, the volume coordinate of each tin solder can be calculated by acquiring the position coordinate of each tin solder on the three-dimensional rectangular coordinate system 13, the shape of each tin solder on the solder plate 11 can be obtained based on the volume of each tin solder, the contact area of the tin solder and the bonding pad and the height of the tin solder, and the shape of the tin solder before the LED is placed on the solder plate 11 is acquired, so that the welding quality can be conveniently detected in the subsequent steps.
Referring to fig. 1 and 6, step S5 is to acquire and amplify the image information of the solder joint based on the image capturing unit 51 to obtain amplified information of the solder joint, analyze the contact surface and the contact position of the LED pin and the solder tin based on the amplified information of the solder joint, and display the analyzed information on the three-dimensional rectangular coordinate system 13. The step S5 specifically comprises the following steps:
in step S51, the image pickup unit 51 and the amplifying unit 52 are acquired and a data connection between the image pickup unit 51 and the amplifying unit 52 is established.
In step S52, the welding position is photographed based on the image pickup unit 51, and a plurality of pieces of welding position image information are obtained and stored.
Step S53, acquiring and amplifying the plurality of pieces of welding position image information based on the amplifying unit 52, obtaining and storing the plurality of pieces of welding position image amplified information.
Step S54, the LED model is obtained, and LED pin size data is obtained based on the LED model. The LED pin size data comprises length data, width data and height data of the LED pins.
And step S55, analyzing the amplified information of the welded part image to acquire the LED pin position information.
In step S56, a data connection between the amplifying unit 52 and the three-dimensional rectangular coordinate system 13 is established, and the LED pin positions are displayed and stored in the three-dimensional rectangular coordinate system 13.
Step S57, based on the image enlargement information of the plurality of soldered portions, the contact surface between the LED pin and the solder and the contact position between the LED pin and the solder are analyzed, and the contact surface information between the LED pin and the solder and the contact position information between the LED pin and the solder are displayed and stored in the three-dimensional rectangular coordinate system 13.
In operation, the image information of the welding position is shot and amplified based on the shooting unit 51 and the amplifying unit 52 to obtain the image amplifying information of the welding position, the size information of the LED pins is obtained, the LED pins are positioned based on the image amplifying information of the welding position, the contact surface and the contact position of the LED pins and the tin solder are analyzed, and the coordinate display is carried out on the contact surface and the contact position of the LED pins and the tin solder in the three-dimensional rectangular coordinate system 13, so that the welding quality can be conveniently detected in the subsequent steps.
Referring to fig. 1 and 7, step S6 is to determine the pressure of the LED pin against the solder based on the contact surface information and the contact position information of the LED pin against the solder, and determine the stress of the solder based on the pressure of the LED pin against the solder. The step S6 specifically comprises the following steps:
step S61, the contact surface information and the contact position information of the LED pins and the solder are obtained and stored. The contact surface information comprises contact surface type information and contact surface number information, wherein the contact surface type information comprises a surface formed by a long side and a wide side of an LED pin and a contact surface of tin solder, a surface formed by a long side and a high side of the LED pin and a contact surface formed by a wide side and a high side of the LED pin and a contact surface of tin solder. The number of the contact surfaces comprises the number of the contact surfaces of the surface formed by the long side and the wide side of the LED pin and the tin solder, the number of the contact surfaces of the surface formed by the long side and the high side of the LED pin and the tin solder and the number of the contact surfaces of the surface formed by the wide side and the high side of the LED pin and the tin solder. The contact position information includes contact edge information, that is, information of a contact edge position with the solder in a contact plane of the LED pin and the solder, and contact area information, that is, information of a contact area in a contact plane of the LED pin and the solder.
Step S62, judging the number of pressures generated by the LED pins on the tin solder when the LED pins are in contact with the tin solder, namely the number of stressed materials of the tin solder, based on the number information of the contact surfaces of the LED pins and the tin solder, and obtaining the number information of the stressed materials. The force generated by the LED pins on the tin solder is divided into the force generated by the LED pins and each contact surface of the tin solder, and the force generated by the tin solder is analyzed. If the number of stress is four, the tin solder is subjected to the force generated by the four faces of the LED pins.
Step S63, judging the pressure direction of the LED pin to the tin solder when the LED pin contacts the tin solder based on the contact surface type information of the LED pin and the tin solder. The opposite direction of the pressure direction is the stress direction of the tin solder, and the pressure direction is the direction which points to the tin solder by the LED pins and is perpendicular to the contact surface. And if the tin solder contacts with a plurality of surfaces of the LED pins, obtaining a plurality of stress direction information. If the contact surface of the LED pin and the tin solder is the lower end plane formed by the long side and the wide side of the LED pin, the stress direction of the tin solder is the direction that the lower end plane formed by the long side and the wide side of the LED pin points to the tin solder and is perpendicular to the lower end plane formed by the long side and the wide side of the LED pin.
Step S64, judging the stress point position of the tin solder based on the contact edge information of the LED pins and the tin solder, wherein the central position of the contact surface of the tin solder and one surface of the LED pins is the stress point position of the tin solder. If one plane of the LED pins is completely contacted with the tin solder, the direction of the stress point is the center position of the plane. If one plane of the LED pin contacts with the tin solder part, the direction of the stress point is the center position of the contact area of the plane and the tin solder. And if the tin solder contacts with a plurality of surfaces of the LED pins, obtaining position information of a plurality of stress points.
Step S65, judging the stress of the tin solder based on the contact area information of the LED pins and the tin solder, wherein the stress is larger as the contact area of the tin solder and one surface of the LED pins is larger, and if the tin solder contacts with a plurality of surfaces of the LED pins, obtaining a plurality of stress point size information. When the LED pin plane is in full contact with the solder, the solder receives the maximum pressure of the force of the contact surface.
In application, the stress condition of the LED pins on the tin solder is judged based on the type of contact surfaces, the number of contact surfaces, the contact edges, the contact area and the contact area of the LED pins and the tin solder, so that the stress condition of the tin solder is judged, the force generated by the LED pins on the tin solder is divided into the force generated by each contact surface of the LED pins and the tin solder, and the accuracy of the stress condition of the tin solder when the LED pins squeeze the tin solder is improved, so that the accuracy of the detection of the welding quality of the LED is improved.
Referring to fig. 1 and 8, step S7 obtains shape information of the solder and stress information of the solder, obtains a plurality of standard shapes of the solder to be extruded according to each solder shape and each solder stress based on the extrusion analysis model, and stores the plurality of standard shape information. The step S7 specifically comprises the following steps:
Step S71, tin solder shape information and tin solder stress information are obtained and stored. The tin solder stress condition information comprises stress number information, a plurality of stress direction information, a plurality of stress point position information and a plurality of stress point size information.
Step S72, acquiring the extrusion analysis model and establishing signal connection between the extrusion analysis model and the three-dimensional rectangular coordinate system 13.
Step S73, inputting the tin solder shape information, the number of forces information, the multiple forces direction information, the multiple forces point position information and the multiple forces point size information of each tin solder on the solder board 11 into the extrusion analysis model, obtaining the standard shapes to be generated after the multiple tin solders are extruded, storing the multiple tin solder standard shape information, and displaying the multiple tin solder standard shape information in the three-dimensional rectangular coordinate system 13.
In the application, based on the extrusion analysis model, the tin solder shape information, the stress number information, the stress direction information, the stress point position information and the stress point size information are obtained, the standard shape which is generated by the tin solder after the LED pins are extruded and pressed is generated, the accuracy of the deformation degree of the tin solder when the LED pins extrude the tin solder is improved, and therefore the accuracy of the welding quality detection of the LED is improved.
Referring to fig. 1 and 9, step S8, reconstructing the tin solder on the solder plate 11 by using an algorithm based on the image enlargement information of the welded part to obtain the reconstruction information of the welding point, that is, the shape information of the tin solder on the solder plate 11 in the actual situation, comparing the reconstruction information of the welding point with the standard shape information, if the reconstruction information of the welding point is consistent with the standard shape information, the quality detection of the welding point is qualified, and if the reconstruction information of the welding point is inconsistent with the standard shape information, the quality detection of the welding point is not qualified. The step S8 specifically comprises the following steps:
step S81, acquiring and storing the image amplification information of a plurality of welding positions.
And step S82, carrying out three-dimensional reconstruction on the shape of the tin solder on the welding plate 11 based on the image amplification information of the welding positions, and restoring welding point reconstruction information which is the information of the welding positions of the LED pins and the tin solder on the welding plate 11. It should be noted that the algorithm in the embodiments of the present application refers to a three-dimensional reconstruction algorithm based on deep learning.
Step S83, a three-dimensional model database is obtained to store the reconstruction information data of a plurality of welding spots.
Step S84, a comparison unit is obtained and data connection between the comparison unit and the three-dimensional model database and the extrusion analysis model is established.
Step S85, based on the comparison unit, the standard shape information of the tin solder is compared with the reconstruction information of the welding spot at the corresponding position, and whether the quality problem occurs during welding of the welding spot is judged.
And S86, if the welding spot reconstruction information at the welding spot is consistent with the corresponding tin solder standard shape information, no welding quality problem exists at the welding spot. If the reconstruction information of the welding spot at the welding spot is inconsistent with the standard shape information of the corresponding tin solder, the welding quality problem exists at the welding spot.
In step S87, data connection between the comparing unit and the three-dimensional rectangular coordinate system 13 is established, and all welding spots with welding quality problem on the welding plate 11 are marked and displayed in the three-dimensional rectangular coordinate system 13.
In the application, a three-dimensional reconstruction algorithm based on deep learning acquires image amplification information of a plurality of welding positions and carries out three-dimensional reconstruction, the information of the welding positions of the LED pins and the tin solder on the welding plate 11 is restored, namely welding spot reconstruction information, the welding spot reconstruction information is compared with standard shape information of the tin solder, whether the actual shape of the tin solder on the welding plate 11 is consistent with the standard shape is judged by analysis, if the actual shape of the tin solder on the welding plate is inconsistent with the standard shape, the problem of welding quality exists, the fixing and electric connection quality of the LED are affected, and the accuracy of detecting the welding quality of the LED is improved.
The embodiment of the application also discloses a welding quality detection system for the LED lamp panel.
Referring to fig. 10, the led lamp panel welding quality detection system includes a pad detection module 1, a corresponding position detection module 2, a corresponding position judgment module 3, a tin solder shape analysis module 4, a contact analysis module 5, a stress analysis module 6, a standard shape analysis module 7, and a reconstruction judgment module 8.
The pad inspection module 1 includes a bonding board 11, a pad inspection unit 12, and a three-dimensional rectangular coordinate system 13. The bonding pad 11 is sequentially distributed with a plurality of bonding pads, and the bonding pad detecting unit 12 is configured to detect positions, types and sizes of the bonding pads on the bonding pad 11 and then output signals of the positions, types and sizes of the bonding pads.
The three-dimensional rectangular coordinate system 13 is respectively connected with the solder board 11 and the solder pad detecting unit 12 through signals. The three-dimensional rectangular coordinate system 13 is used for receiving the pad position signal, the pad type signal and the pad size signal and displaying coordinates of the corresponding positions of the bonding pad 11 on the three-dimensional rectangular coordinate system 13.
Referring to fig. 10, the corresponding position detecting module 2 includes a temperature sensing unit 21, a temperature comparing unit 22, and a positioning unit 23, and the temperature sensing unit 21 and the positioning unit 23 are disposed on the bonding pad 11. An output end of the temperature sensing unit 21 is in signal connection with an input end of the temperature comparing unit 22, and the temperature sensing unit 21 is used for detecting the temperature of the solder plate 11 after the soldering operation is performed on the solder plate 11 and outputting a temperature signal to the temperature comparing unit 22.
The temperature comparing unit 22 is preset with a standard temperature threshold, and the temperature comparing unit 22 is used for comparing the temperature signal with a preset standard temperature threshold signal after receiving the temperature signal, and outputting a high temperature signal if the temperature signal exceeds the standard temperature threshold signal. The temperature of the surface of the solder plate 11 increases due to the temperature of the solder during the soldering process, and the temperature sensing unit 21 detects the temperature of the solder plate 11 to determine the location area of the solder on the solder plate 11. Wherein the standard temperature threshold should be higher than the original temperature of the solder plate 11 before being tin-soldered.
The input end of the positioning unit 23 is configured to be in signal connection with the output end of the temperature comparing unit 22, and the output end of the positioning unit 23 is configured to be in signal connection with the input end of the three-dimensional rectangular coordinate system 13. The positioning unit 23 is configured to receive the high temperature signal, position the solder region on the solder plate 11 at the excessive temperature, output a solder position signal, and display the position region in a three-dimensional rectangular coordinate system 13.
Referring to fig. 10, the output terminal of the corresponding position determining module 3 is configured to be in signal connection with the input terminal of the positioning unit 23 and the input terminal of the three-dimensional rectangular coordinate system 13. The corresponding position judging module 3 is configured to analyze the degree of correspondence between the solder position area and the pad position area after receiving the solder position signal and the pad position signal. When the area of the solder plate 11 where the solder does not cover the pad exceeds 10% of the corresponding pad area or the area exceeding the pad exceeds 10% of the corresponding pad area, the solder on the solder plate 11 does not correspond to the output position corresponding failure signal with the corresponding pad area. When the uncovered area of the solder on the solder plate 11 does not exceed 10% of the land area until the uncovered area exceeds 10% of the land area, the solder on the solder plate 11 and the corresponding land area meet the output position corresponding qualified signal.
The input of the solder shape analysis module 4 is arranged in signal connection with the output of the positioning unit 23. The solder shape analysis module 4 is configured to receive the solder position signal, analyze coordinate position data of the solder on the three-dimensional rectangular coordinate system 13, calculate a volume of each solder on the solder plate 11 based on the triple integral calculation model, measure solder contact area information and solder height information, analyze solder shape information, and output a solder shape signal.
Referring to fig. 10, the contact analysis module 5 includes an image capturing unit 51 and an amplifying unit 52, and an output terminal of the image capturing unit 51 is signal-connected to an input terminal of the amplifying unit 52. The image pickup unit 51 is for picking up image information of the weld on the weld plate 11 and outputting the weld image signal to the amplifying unit 52. The amplifying unit 52 is configured to receive the image signal of the welding position and output an amplified image signal of the welding position after performing image amplification processing. The image amplification signals of the welding positions comprise signals of the contact surfaces of the LED pins and the tin solder and contact position signals.
An input of the force analysis module 6 is configured to be in signal connection with an output of the amplifying unit 52. The stress analysis module is used for receiving the contact surface signals and the contact position signals, judging the pressure of the LED pins on the tin solder, analyzing and processing the stress condition of each tin solder on the welding plate 11, and outputting a tin solder stress signal.
Referring to fig. 10, an input of the standard shape analysis module 7 is configured to be in signal connection with an output of the force analysis module 6. The standard shape analysis module 7 is used for receiving the tin solder stress signals, analyzing and judging the standard shape which each tin solder on the welding plate 11 should form under the current stress condition based on the extrusion analysis model according to the tin solder stress condition, and outputting the tin solder standard shape signals.
The reconstruction judgment module 8 includes a weld reconstruction unit, a shape comparison unit, and a weld judgment unit. The output end of the welding spot reconstruction unit is in signal connection with the input end of the shape comparison unit. The solder joint reconstruction unit is configured to be in signal connection with the amplification unit 52 and the standard shape analysis module 7. The welding spot reconstruction unit is used for receiving the image amplified signal of the welding position, then performing three-dimensional reconstruction on the shape of the actually extruded tin solder on the welding plate 11, and outputting a welding spot reconstruction signal to the shape comparison unit.
Referring to fig. 10, an input of the shape comparison unit is configured to be in signal connection with an output of the solder joint reconstruction unit and an output of the standard shape analysis module 7. The shape comparison unit is used for comparing the shape of the solder on the solder plate 11 actually pressed after receiving the solder joint reconstruction signal and the standard shape signal of the solder with the standard shape which each solder on the solder plate 11 should form under the current stress condition. And outputting a shape conforming signal if the actual shape conforms to the standard shape. And if the actual shape is inconsistent with the standard shape, outputting a shape inconsistent signal.
The input end of the welding spot judging unit is in signal connection with the output end of the shape comparing unit. The solder joint judging unit is used for judging whether the actual extruded condition of the tin solder on the solder plate 11 is consistent with the standard condition after receiving the signal with consistent shape and the signal with inconsistent shape. And if the welding quality of the LEDs is consistent, outputting welding qualification signals, and if the welding quality of the LEDs is inconsistent, outputting welding quality failure signals. The output end of the welding spot judging unit is in signal connection with the input end of the three-dimensional rectangular coordinate system 13. And the three-dimensional rectangular coordinate system 13 displays coordinates of the positions of the unqualified welding spots after receiving the unqualified welding quality signals.
The foregoing are all preferred embodiments of the present application, and are not intended to limit the scope of the present application in any way, therefore: all equivalent changes in structure, shape and principle of this application should be covered in the protection scope of this application.

Claims (8)

1. The welding quality detection method for the LED lamp panel is characterized by comprising the following steps of:
acquiring a welding plate (11) and a three-dimensional rectangular coordinate system (13) and establishing data connection, detecting the position and the type of a welding plate on the welding plate (11) and detecting the size of the welding plate respectively;
the method comprises the steps that a temperature sensing unit (21) is obtained to detect the surface temperature of the solder plate (11) after tin soldering, a positioning unit (23) is obtained to position the position, on which the temperature value of the solder plate (11) exceeds a standard temperature threshold value, of the solder plate (11), namely the position of the tin soldering, and the position of the tin soldering is compared with the position of the bonding pad and analyzed;
If the area of the solder plate (11) exceeding the solder pad exceeds 10% of the area corresponding to the solder pad or the area of the solder pad not covered by the solder pad exceeds 10% of the area corresponding to the solder pad, the quality of the solder brushing the solder in the area corresponding to the solder pad is not qualified, otherwise, the quality of the solder brushing the solder in the area corresponding to the solder pad is qualified;
acquiring boundary coordinates of the tin solder on each bonding pad of the welding plate (11) based on the three-dimensional rectangular coordinate system (13), calculating the volume of the tin solder on each bonding pad based on a triple integral calculation model, and analyzing the shape of the tin solder on the welding plate (11);
acquiring and amplifying the image information of the welding position based on the image pick-up unit (51) to obtain the image amplifying information of the welding position, analyzing the contact surface and the contact position of the LED pins and the tin solder based on the image amplifying information of the welding position, and displaying the contact surface and the contact position on the three-dimensional rectangular coordinate system (13);
judging the pressure of the LED pins on the tin solder based on the contact surface information and the contact position information of the LED pins and the tin solder, and further judging the stress condition of the tin solder;
the step of judging the pressure of the LED pin to the tin solder based on the contact surface information and the contact position information of the LED pin and the tin solder so as to judge the stress condition of the tin solder specifically comprises the following steps:
Acquiring and storing contact surface information and contact position information of the LED pins and the tin solder, wherein the contact surface information comprises contact surface type information and contact surface number information, and the contact position information comprises contact edge information and contact area information;
judging the number of pressures generated by the LED pins on the tin solder when the LED pins are in contact with the tin solder, namely the number of stresses of the tin solder, based on the number information of the contact surfaces of the LED pins and the tin solder, so as to obtain the number information of the stresses;
judging the pressure direction of the LED pin to the tin solder when the LED pin contacts the tin solder based on the contact surface type information of the LED pin and the tin solder, wherein the opposite direction of the pressure direction is the stress direction of the tin solder, and if the tin solder contacts a plurality of surfaces of the LED pin, obtaining a plurality of stress direction information;
judging the stress point position of the tin solder based on the contact edge information of the LED pin and the tin solder, wherein the central position of the contact surface of the tin solder and one surface of the LED pin is the stress point position of the tin solder, and if the tin solder contacts with a plurality of surfaces of the LED pin, obtaining a plurality of stress point position information;
judging the stress of the tin solder based on the contact area information of the LED pins and the tin solder, wherein the stress is larger as the contact area of the tin solder and one surface of the LED pins is larger, and if the tin solder contacts with a plurality of surfaces of the LED pins, a plurality of stress point size information is obtained;
Obtaining the shape of the tin solder, obtaining the standard shape of the extruded tin solder based on an extrusion analysis model according to the stress condition of the tin solder, and storing the standard shape information;
the step of obtaining the shape of the tin solder and the stress condition of the tin solder, obtaining the standard shape of the extruded tin solder based on an extrusion analysis model and storing the standard shape information specifically comprises the following steps:
acquiring and storing tin solder shape information and tin solder stress condition information, wherein the tin solder stress condition information comprises stress number information, a plurality of stress direction information, a plurality of stress point position information and a plurality of stress point size information;
acquiring an extrusion analysis model and establishing signal connection;
inputting tin solder shape information, stress number information, multiple stress direction information, multiple stress point position information and multiple stress point size information of each tin solder on the welding plate (11) into the extrusion analysis model to respectively obtain standard shapes which are generated after the multiple tin solders are extruded and store the multiple tin solder standard shape information;
and reconstructing tin solder on the welding plate (11) by adopting an algorithm based on the image amplification information of the welding position to obtain welding spot reconstruction information, comparing the welding spot reconstruction information with standard shape information, if the comparison result is consistent, detecting the welding spot quality to be qualified, and if the comparison result is inconsistent, detecting the welding spot quality to be unqualified.
2. The method for detecting the welding quality of the LED lamp panel according to claim 1, wherein the steps of obtaining the welding plate (11) and the three-dimensional rectangular coordinate system (13) and establishing data connection, detecting the positions of the welding pads and the types of the welding pads on the welding plate (11) and detecting the sizes of the welding pads respectively comprise the following steps:
acquiring a welding plate (11) and a three-dimensional rectangular coordinate system (13) and establishing data connection between the welding plate (11) and the three-dimensional rectangular coordinate system (13);
the welding plate (11) corresponds to the three-dimensional rectangular coordinate system (13), the vertex of the welding plate (11) corresponds to the origin of the three-dimensional rectangular coordinate system (13), the plane of the welding plate (11) for welding components corresponds to the x-y plane of the three-dimensional rectangular coordinate system (13), and two adjacent side lengths connected with the vertex of the welding plate (11) corresponding to the origin of the three-dimensional rectangular coordinate system (13) correspond to the x-axis and the y-axis of the three-dimensional rectangular coordinate system (13) respectively;
detecting the position of each bonding pad on the bonding plate (11), displaying the corresponding position on the three-dimensional rectangular coordinate system (13) and storing the corresponding position;
and detecting the types of the bonding pads with different sizes on the bonding pad (11), and respectively detecting and storing the size data of the bonding pads with different types.
3. The method for detecting the welding quality of the LED lamp panel according to claim 1, wherein the step of obtaining the temperature sensing unit (21) to detect the surface temperature of the solder plate (11) after brushing the tin solder, and obtaining the positioning unit (23) to position the position of the solder plate (11) where the temperature value exceeds the standard temperature threshold, that is, the position of the tin solder on the solder plate (11), and comparing and analyzing the position of the tin solder with the position of the bonding pad specifically includes:
acquiring a temperature sensing unit (21) and establishing data connection between the temperature sensing unit (21) and the welding plate (11);
detecting a surface temperature of the solder plate (11) after the solder brushing operation of the solder plate (11) based on the temperature sensing unit (21);
comparing the temperature value of each position on the welding plate (11) with a preset standard temperature threshold value in the temperature sensing unit (21);
acquiring a positioning unit (23) and establishing data connection between the positioning unit (23) and the temperature sensing unit (21) and the welding plate (11) respectively;
the positioning unit (23) is used for positioning the position of the temperature value on the welding plate (11) exceeding the standard temperature threshold, namely the position of the tin solder on the welding plate (11), and displaying the position in the three-dimensional rectangular coordinate system (13);
And comparing the tin solder position on the welding plate (11) in the three-dimensional rectangular coordinate system (13) with the welding plate position, and analyzing the corresponding situation of the welding plate position and the tin solder position on the welding plate (11).
4. The method for detecting the soldering quality of an LED lamp panel according to claim 1, wherein if the area of the solder plate (11) exceeding the solder pad exceeds 10% of the area corresponding to the solder pad or the area of the solder not covering the solder pad exceeds 10% of the area corresponding to the solder pad, the quality of the solder brushed corresponding to the solder pad area is not qualified, otherwise the quality of the solder brushed corresponding to the solder pad area is qualified, specifically comprising the steps of:
acquiring the position of tin solder on the welding plate (11) and the position of the bonding pad and storing position data;
judging whether the tin solder position area on the welding plate (11) exceeds the welding disc position area;
if the tin solder position area on the welding plate (11) exceeds the welding plate position area, judging the percentage of the welding plate (11) position area exceeding the welding plate to the welding plate position area;
if the position area of the tin solder on the welding plate (11) exceeds the position area of the welding pad by more than 10% of the position area of the welding pad, the position area of the tin solder on the welding plate (11) and the position area of the corresponding welding pad are unqualified during welding;
If the solder position area on the bonding pad does not exceed, namely does not cover the bonding pad position area completely, judging the percentage of the solder position area on the bonding pad (11) which is not covered by the solder on the bonding pad to the bonding pad position area;
if the position area of the solder plate (11) which is not covered by the tin solder and occupies more than 10% of the position area of the solder pad, the position area of the tin solder on the solder plate (11) and the position area corresponding to the solder pad are unqualified during welding;
and if the uncovered area and the exceeding area of the tin solder on the welding plate (11) are not more than 10% of the welding plate area, the tin solder position area on the welding plate (11) is qualified with the corresponding welding plate position area during welding.
5. The method for detecting the soldering quality of an LED lamp panel according to claim 1, wherein the step of obtaining the boundary coordinates of the solder on each of the pads of the solder board (11) based on the three-dimensional rectangular coordinate system (13), calculating the volume of the solder on each of the pads based on a triple integral calculation model, and analyzing the shape of the solder on the solder board (11) specifically comprises:
acquiring the coordinate position of the tin solder on the welding plate (11) on the three-dimensional rectangular coordinate system (13) and storing coordinate position data;
Acquiring and storing a triple integral calculation model, wherein the triple integral calculation model is based on the triple integral calculation model for calculating the volume of an irregular object;
establishing data connection between the triple integral calculation model and the three-dimensional rectangular coordinate system (13);
the triple integral calculation model acquires boundary coordinate data of solder materials on the solder plate (11);
calculating the volume of the tin solder on the welding plate (11) based on boundary coordinate data information of the tin solder on the welding plate (11) to obtain a plurality of tin solder volume information;
measuring the contact area of each tin solder on the welding plate (11) and the welding disc and the height of each tin solder to obtain a plurality of tin solder contact area information and tin solder height information;
and analyzing the shape of the solder before the component is placed after the solder is brushed on the solder plate (11) based on the volume information of the solder, the contact area information of the solder and the height information of the solder, so as to obtain a plurality of shape information of the solder.
6. The method for detecting the welding quality of the LED lamp panel according to claim 1, wherein the step of acquiring and amplifying the image information of the welding place based on the camera unit (51) to obtain the amplified information of the welding place, analyzing the contact surface and the contact position of the LED pin and the tin solder based on the amplified information of the welding place, and displaying the contact surface and the contact position on the three-dimensional rectangular coordinate system (13) specifically comprises the following steps:
Acquiring an image pickup unit (51) and an amplifying unit (52) and establishing a data connection;
shooting the welding position based on the image pick-up unit (51) to obtain welding position image information and storing the welding position image information;
acquiring welding position image information, amplifying the welding position image information based on the amplifying unit (52), and acquiring and storing welding position image amplified information;
acquiring an LED model and acquiring the LED pin size data based on the LED model;
acquiring the LED pin position information based on the welding position image amplification information;
establishing data connection between the amplifying unit (52) and the three-dimensional rectangular coordinate system (13), displaying the LED pin position in the three-dimensional rectangular coordinate system (13) and storing the LED pin position;
and analyzing the contact surface and the contact position of the LED pins and the tin solder based on the image amplification information of the welding part, and displaying and storing the contact surface information and the contact position information on the three-dimensional rectangular coordinate system (13).
7. The method for detecting the welding quality of the LED lamp panel according to claim 1, wherein the step of reconstructing the tin solder on the welding plate (11) by using an algorithm based on the image amplification information of the welding place to obtain the reconstruction information of the welding point, comparing the reconstruction information of the welding point with the standard shape information, if the comparison result is consistent, detecting the welding point quality to be qualified, and if the comparison result is inconsistent, detecting the welding point quality to be unqualified specifically comprises the following steps:
Acquiring and storing the image amplification information of the welding position;
three-dimensional reconstruction is carried out on the image amplification information of the welding positions based on an algorithm, and welding spot reconstruction information of the welding positions of the LED pins and the tin solder on the welding plate (11) is restored;
acquiring a three-dimensional model database and storing reconstruction information data of a plurality of welding spots;
acquiring a comparison unit and establishing data connection between the comparison unit and the three-dimensional model database and between the comparison unit and the extrusion analysis model;
comparing the standard shape information of the tin solder with the reconstruction information of the welding spots at the corresponding positions, and judging whether quality problems occur during welding of the welding spots;
if the welding spot reconstruction information at the welding spot is consistent with the corresponding tin solder standard shape information, the welding quality problem at the welding spot is avoided; if the reconstruction information of the welding spot at the welding spot is inconsistent with the standard shape information of the corresponding tin solder, the welding quality problem occurs at the welding spot;
and marking all welding spots with welding quality problems on the welding plate (11) and displaying the welding spots on the three-dimensional rectangular coordinate system (13).
8. A system for detecting welding quality of an LED lamp panel, applied to the method as claimed in any one of claims 1 to 7, comprising:
the bonding pad detection module (1) comprises a bonding pad (11), a bonding pad detection unit (12) and a three-dimensional rectangular coordinate system (13), wherein the bonding pad (11) comprises a plurality of bonding pads, and the bonding pad detection unit (12) is used for respectively detecting bonding pad positions, bonding pad types and bonding pad sizes of the plurality of bonding pads and outputting bonding pad position signals, bonding pad type signals and bonding pad size signals;
The welding plate (11) and the welding plate detection unit (12) are in signal connection with the three-dimensional rectangular coordinate system (13), and the three-dimensional rectangular coordinate system (13) is used for receiving the welding plate position signal, the welding plate type signal and the welding plate size signal and displaying the welding plate position signal, the welding plate type signal and the welding plate size signal at corresponding positions of the welding plate (11) on the three-dimensional rectangular coordinate system (13);
the corresponding position detection module (2) comprises a temperature sensing unit (21), a temperature comparison unit (22) and a positioning unit (23), wherein the temperature sensing unit (21) and the positioning unit (23) are arranged on the welding plate (11), and the temperature sensing unit (21) is used for detecting the temperature on the welding plate (11) after the operation of brushing tin solder and outputting a temperature signal;
the temperature comparison unit (22) is in signal connection with the temperature sensing unit (21), a standard temperature threshold value is preset in the temperature comparison unit (22), the temperature comparison unit (22) is used for comparing the temperature signal with the standard temperature threshold value signal after receiving the temperature signal, and a high-temperature signal is output if the temperature signal exceeds the standard temperature threshold value signal;
the positioning unit (23) is configured to be in signal connection with the temperature comparison unit (22), the output end of the positioning unit (23) is in signal connection with the input end of the three-dimensional rectangular coordinate system (13), and the positioning unit (23) is used for outputting a tin solder position signal after positioning an area with an excessively high temperature on the welding plate (11) after receiving the high temperature signal and marking the positioning area in the three-dimensional rectangular coordinate system (13);
The corresponding position judging module (3) is configured to be in signal connection with the positioning unit (23) and the three-dimensional rectangular coordinate system (13), the corresponding position judging module (3) receives the tin solder position signal and the bonding pad position signal to analyze the corresponding degree of a tin solder position area and a bonding pad position area, and when the area of the bonding pad (11) which is not covered by the tin solder exceeds 10% of the corresponding bonding pad area or the area of the bonding pad which is beyond 10% of the corresponding bonding pad area, the tin solder on the bonding pad (11) and the corresponding bonding pad area do not accord with an output position corresponding disqualification signal;
the solder shape analysis module (4) is connected with the positioning unit (23) in a signal manner, and is used for receiving the solder position area signal, then calculating the coordinate position data of the solder on the three-dimensional rectangular coordinate system (13) and calculating the volume of each solder on the solder plate (11) based on a triple integral calculation model, and analyzing the solder shape information and outputting a solder shape signal after measuring the solder contact area information and the solder height information;
the contact analysis module (5) comprises an image pick-up unit (51) and an amplifying unit (52), wherein the image pick-up unit (51) is in signal connection with the amplifying unit (52), the image pick-up unit (51) is used for picking up image information of a welding position on a welding plate (11) and outputting the image information of the welding position to the amplifying unit (52), and the amplifying unit (52) is used for receiving the image information of the welding position to amplify and then outputting an amplified signal of the welding position, wherein the amplified signal of the welding position comprises a contact surface signal of an LED pin and tin solder and a contact position signal;
The stress analysis module (6) is connected with the amplifying unit (52) in a signal manner, and is used for receiving the contact surface signals and the contact position signals, judging the pressure of the LED pins on the tin solder, analyzing the stress condition of the tin solder and then outputting a tin solder stress signal;
the standard shape analysis module (7) is configured to be in signal connection with the stress analysis module (6), and the standard shape analysis module (7) is used for receiving the tin solder stress signal, judging and analyzing the standard shape which the tin solder should form under the current stress condition based on an extrusion analysis model according to the tin solder stress condition and outputting a tin solder standard shape signal; the method comprises the steps of,
the reconstruction judging module (8) is configured to be in signal connection with the amplifying unit (52) and the standard shape analyzing module (7), the reconstruction judging module (8) is used for receiving an image amplifying signal of a welding position, then carrying out three-dimensional reconstruction on the actual extrusion shape of the tin solder on the welding plate (11) to output a welding spot reconstruction signal, comparing the welding spot reconstruction signal with the standard shape signal of the tin solder, when the welding spot reconstruction signal is consistent with the standard shape signal of the tin solder, the welding quality of the welding spot is normal, and when the welding spot reconstruction signal is inconsistent with the standard shape signal of the tin solder, the welding quality of the welding spot is abnormal.
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