Closed-loop control system for wave crest height

Abstract

The utility model discloses a wave crest height closed-loop control system, comprising a tin furnace, the top of which is provided with a nozzle used for carrying out wave soldering on a workpiece to form tin waves; the detection element is arranged at the upper end of the nozzle and connected with a moving assembly, and the moving assembly can drive the detection element to move to a plurality of detection positions on the tin wave so as to obtain wave crest height information; the detection element and the moving assembly are both in signal connection with the control element, and the control element is used for controlling the moving assembly to move and driving the detection element to reach any detection position; the wave crest motor is arranged on one side of the nozzle, the control element is used for receiving the height information on the multiple detection positions and calculating the actual height value of the tin wave, and the control element can control the rotating speed of the wave crest motor according to the difference value between the actual height value and the height value set by the tin wave so as to carry out automatic calibration. According to the wave crest height closed-loop control system, the tin wave height is automatically calibrated, and the efficiency and precision of automatic calibration are improved.

Description

Technical Field

[0001] The utility model relates to a wave soldering device which relates to the technical field, and more specifically to a wave crest height closed-loop control system. Background Art

[0002] In wave soldering production, factors such as flux coating, preheating temperature, wave crest height and tin furnace temperature often lead to poor soldering of the wave crest, and the wave crest height is greatly affected by human control factors. During the production operation of the machine, the tin furnace will produce tin slag, consume solder, and affect the wave crest height. Even at the same wave crest running speed, the wave crest height cannot be guaranteed.

[0003] In the related art, in order to calibrate the wave peak height, a steel ruler is manually inserted into the tin wave to contact the surface of the tin furnace nozzle to measure the wave peak height, and then the motor speed is adjusted to reach the required welding height. However, the above operation is affected by the technician's experience, the operation time is long and the calibration accuracy is not high.

[0004] In summary, how to provide a control system that can automatically calibrate the wave peak height is a problem that needs to be solved urgently by those skilled in the art. Utility Model Content

[0005] In view of this, the purpose of the utility model is to provide a wave peak height closed-loop control system to automatically calibrate the actual height of the tin wave without human intervention, reduce the errors caused by human factors, improve the efficiency and accuracy of automatic calibration, and ensure the quality of wave soldering of workpieces.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] A wave crest height closed-loop control system, comprising:

[0008] A tin furnace, the top of which is provided with a nozzle for wave soldering the workpiece to form a tin wave;

[0009] A detection element is disposed at the upper end of the nozzle and is connected to a moving component, wherein the moving component can drive the detection element to move to multiple detection positions on the tin wave to obtain wave peak height information;

[0010] A control element, the detection element and the moving component are both connected to the control element by signal, and the control element is used to control the movement of the moving component to drive the detection element to reach any of the detection positions;

[0011] The crest motor is arranged on one side of the nozzle. The control element is used to receive the height information of multiple detection positions and calculate the actual height value of the tin wave. The control element can control the rotation speed of the crest motor according to the difference between the actual height value and the set height value of the tin wave for automatic calibration.

[0012] Preferably, a height measuring element for obtaining the height of the tin furnace is provided on one side of the tin furnace, and the control element is used to receive the height information of the tin furnace, the moving height information of the detection element, and the distance information between the detection element and the nozzle to obtain the peak height information at the detection position.

[0013] Preferably, a first detection position, a second detection position and a third detection position are respectively provided along the length direction of the tin wave, the first detection position and the third detection position correspond to the two ends of the tin wave, and the second detection position is provided in the middle of the tin wave.

[0014] Preferably, the moving assembly includes an X-axis moving part, a Y-axis moving part and a Z-axis moving part, two groups of the X-axis moving parts are arranged in parallel and are both connected to the Y-axis moving part, and the Z-axis moving part is connected to the Y-axis moving part.

[0015] Preferably, the X-axis moving part, the Y-axis moving part, the Z-axis moving part, the peak motor and the detection element are all provided with a fault module which is signal-connected to the control element.

[0016] The utility model provides a wave crest height closed-loop control system, comprising a tin furnace, a detection element, a moving component, a control element and a wave crest motor, wherein a nozzle is provided on the top of the tin furnace, and wave crest soldering is performed on the workpiece at the nozzle to form a tin wave; the detection element is arranged at the upper end of the nozzle and is connected with a moving component, and the detection element can be driven by the moving component to move to multiple detection positions on the tin wave to obtain wave crest height information; the control element is used to control the movement of the moving component to achieve the effect that the detection element can reach any detection position, and the detection element reaches each detection position in turn to obtain the height of the wave crest corresponding to each detection position and transmits it to the control element, and the control element can calculate the actual height value of the tin wave according to the wave crest height information corresponding to the multiple detection positions, and further, the rotation speed of the wave crest motor is controlled based on the difference between the actual height value of the tin wave and the height value that the tin wave should be set, so as to automatically calibrate the actual height of the tin wave without human intervention, reduce the error caused by human factors, improve the efficiency and accuracy of automatic calibration, and ensure the quality of wave crest soldering of the workpiece. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0018] Figure 1 A schematic diagram of the structure of the wave peak height closed-loop control system provided by the utility model;

[0019] Figure 2 A schematic diagram of the structure of the mobile assembly provided by the utility model;

[0020] Figure 3 A schematic diagram of the structure of the detection element provided by the utility model;

[0021] Figure 4 A schematic diagram of the overall control circuit of the wave crest height closed-loop control system provided by the utility model;

[0022] Figure 5 The control circuit diagram of the wave crest motor provided by the utility model;

[0023] Figure 6 The control circuit diagram of the X-axis moving part provided by the utility model;

[0024] Figure 7 A control circuit diagram of the Y-axis moving element provided by the utility model;

[0025] Figure 8 This is a control circuit diagram of the Z-axis moving part provided by the utility model.

[0026] Figure 1-Figure 8 , the reference numerals include:

[0027] X-axis moving part 1, Y-axis moving part 2, Z-axis moving part 3, detection element 4, first detection position 5, second detection position 6, third detection position 7, height measuring element 8, tin furnace 9, nozzle 10, peak motor 11, tin wave 12. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0029] The core of the utility model is to provide a wave crest height closed-loop control system, which can automatically calibrate the actual height of the solder wave without human intervention, reduce the error caused by human factors, improve the efficiency and accuracy of automatic calibration, and ensure the quality of wave soldering of workpieces.

[0030] The peak height closed-loop control system provided by the utility model includes a tin furnace 9, a detection element 4, a moving component, a control element and a peak motor 11, please refer to Figure 1 , Figure 3 .

[0031] A nozzle 10 is provided on the top of the tin furnace 9 , and a workpiece is wave soldered at the nozzle 10 to form a tin wave 12 . The workpiece may be a circuit board with components mounted thereon, and high-temperature liquid tin contacts the soldering surface of the circuit board to form the tin wave 12 .

[0032] The detection element 4 is arranged at the upper end of the nozzle 10 and is used to detect the tin wave 12 on the workpiece. The detection element 4 can be a contact probe, a non-contact probe, or a sensor element, etc., and can be set in one group or multiple groups.

[0033] The moving component is connected to the detection element 4 to realize the movement of the moving component to the detection position of the tin wave 12. The moving component can be a device formed by combining multiple groups of servo motors and connecting parts, or it can be a manipulator with multiple degrees of freedom, which can realize arbitrary movement above the nozzle 10.

[0034] There are multiple detection positions on the tin wave 12, which are the positions for wave peak height detection. Three, four, or five detection positions can be set. Taking into account the detection accuracy and operation complexity, three detection positions can be preferably set. The position heights of the three points are used to determine whether the wave peak heights at the three detection positions are on the same straight line.

[0035] The control element is used to control the moving component to drive the detection element 4 to move, thereby achieving the technical effect of the detection element 4 reaching any detection position on the tin wave 12.

[0036] Preferably, the control element is a PLC (Programmable Logic Controller), which is easy to expand and has strong flexibility.

[0037] The detection element 4 moves to each detection position to obtain the peak height value corresponding to each detection position and transmit it to the control element. After receiving the height information, the control element calculates that the actual height value of the tin wave 12 is essentially the average value of the peak height detection values ​​at multiple detection positions. The actual height value is compared with the set height value of the tin wave 12, and the difference is analyzed. The rotation speed of the peak motor 11 is further controlled by the control element to realize automatic calibration of the peak height.

[0038] The above-mentioned wave peak height closed-loop control system includes a tin furnace 9, a detection element 4, a moving component, a control element and a wave peak motor 11, wherein a nozzle 10 is provided on the top of the tin furnace 9, and the workpiece is wave-soldered at the nozzle 10 to form a tin wave 12; the detection element 4 is arranged at the upper end of the nozzle 10 and is connected to a moving component, and the detection element 4 can be driven by the moving component to move to multiple detection positions on the tin wave 12 to obtain wave peak height information; the control element is used to control the movement of the moving component to achieve the effect that the detection element 4 can reach any detection position, and the detection element 4 reaches each detection position in turn to obtain the height of the corresponding wave peak at each detection position and transmit it to the control element, and the control element can calculate the actual height value of the tin wave according to the wave peak height information corresponding to the multiple detection positions. Furthermore, the speed of the wave peak motor is controlled based on the difference between the actual height value of the tin wave 12 and the height value that the tin wave 12 should be set to automatically calibrate the actual height of the tin wave 12 without human intervention, thereby reducing the errors caused by human factors, improving the efficiency and accuracy of automatic calibration, and ensuring the quality of wave soldering of the workpiece.

[0039] Based on the above embodiment, a height measuring element 8 for obtaining the height of the tin furnace 9 is provided on one side of the tin furnace 9, and the control element is used to receive the height information of the tin furnace 9, the moving height information of the detection element 4, and the distance information between the detection element 4 and the nozzle 10 to obtain the peak height information at the detection position.

[0040] Please refer to Figure 1 , Figure 2 The height H1 of the tin furnace 9 is obtained by the height measuring element 8. The height measuring element 8 is preferably an electronic ruler, which is convenient for automatically measuring the real-time height value of the tin furnace 9. It can also be achieved through other detection methods, such as combining image processing, sensors and other components.

[0041] The height to which the detection element 4 moves during the detection process is H4, and the distance between the detection element 4 and the nozzle 10 is H3. The height value of the peak at any detection position is H2=H3-H1-H4. The detection element 4 is driven to each detection position by the moving component, and the height value of the tin wave 12 at each detection position is calculated by the above formula, and the actual height value of the tin wave 12 is obtained by the average of the peak height values ​​at multiple detection positions.

[0042] Based on any of the above embodiments, a first detection position 5, a second detection position 6, and a third detection position 7 are respectively provided along the length direction of the tin wave 12. The first detection position 5 and the third detection position 7 correspond to the two ends of the tin wave 12, and the second detection position 6 is provided in the middle of the tin wave 12.

[0043] Please refer to Figure 1The first detection position 5, the second detection position 6, and the third detection position 7 are arranged in sequence along the length direction of the tin wave. The first detection position 5 and the third detection position 7 correspond to the two ends of the tin wave 12, and the second detection position 6 is set in the middle of the tin wave 12. The actual value of the tin wave height is obtained by detecting the wave peak height at the three detection positions.

[0044] Based on any of the above embodiments, the moving component includes an X-axis moving part 1, a Y-axis moving part 2 and a Z-axis moving part 3, two groups of X-axis moving parts 1 are arranged in parallel and are both connected to the Y-axis moving part 2, and the Z-axis moving part 3 is connected to the Y-axis moving part 2.

[0045] Please refer to Figure 1 , Figure 2 The moving component includes an X-axis moving part 1, a Y-axis moving part 2 and a Z-axis moving part 3, wherein the X-axis moving part 1 is provided with two moving parts in three directions connected to each other to form a multi-degree-of-freedom motion of the detection element 4.

[0046] Preferably, the X-axis moving member 1, the Y-axis moving member 2 and the Z-axis moving member 3 all include servo motors, which can achieve higher control accuracy.

[0047] On the basis of any of the above embodiments, the X-axis moving element 1 , the Y-axis moving element 2 , the Z-axis moving element 3 , the peak motor 11 , and the detection element 4 are all provided with a fault module connected to the control element signal.

[0048] Through the setting of the fault module, the fault information of the X-axis moving part 1, the Y-axis moving part 2, the Z-axis moving part 3, the peak motor 11 and the detection element 4 can be reported to the control element in time, so as to promptly notify the user or stop the operation in time to ensure the safety and reliability of the operation.

[0049] Next, the control method for the application of the above-mentioned wave peak height closed-loop control system is introduced, and the control method includes:

[0050] The control element controls the movement of the moving component, driving the detection element to move to each detection position to obtain the height information of the corresponding wave peak;

[0051] The control element receives the height information at each detection position, and calculates the average value of the peak heights at multiple detection positions through the control element, which is the actual height value of the tin wave 12;

[0052] The control element controls the moving component to drive the detection element 4 to move to each detection position according to the calculated height difference between the actual height value of the wave peak and the height value of the wave peak to be set, and the moving distance of the detection element 4 is consistent with the height difference;

[0053] The control element controls and adjusts the rotation speed of the peak motor 11 until the detection element 4 detects the peak signal at the detection position, and then the control element controls the moving component to stop moving, at which time the automatic calibration is completed.

[0054] On the basis of the above embodiment, the detection position includes a first detection position 5, a second detection position 6, and a third detection position 7, and the control element controls the moving component to drive the detection element 4 to move in the direction close to the first detection position 5, the second detection position 6, and the third detection position 7, respectively, until the detection element 4 detects the peak signal respectively;

[0055] The control element receives the height information of the tin furnace 9, the moving height information of the detection element 4, and the distance information between the detection element 4 and the nozzle 10, and calculates the difference between the three to obtain the height value of the wave peak corresponding to any first detection position 5, the second detection position 6, and the third detection position 7 respectively. The control element calculates the actual height value of the tin wave 12.

[0056] Please refer to Figure 1 In actual operation, the control element first controls the moving component to drive the detection element 4 to move toward the first detection position 5 until the detection element 4 detects the peak signal at the first detection position 5. At this time, the moving component stops working. The height of the peak here is calculated by the formula H1=H3-H1-H4, where H4 is the height of the detection element 4 during the detection process, H3 is the distance between the detection element 4 and the nozzle 10, H1 is the height of the tin furnace 9, and H1 is the peak height corresponding to the first detection position 5.

[0057] Then, the control element controls the moving component to drive the detection element 4 to move toward the second detection position 6 until the detection element 4 detects the peak signal at the second detection position 6. At this time, the moving component stops working. The height of the peak here is calculated by the formula H3=H3-H1-H4, where H2 is the peak height corresponding to the second detection position 6.

[0058] Then, the control element controls the moving assembly to drive the detection element 4 to move toward the third detection position 7 until the detection element 4 detects the peak signal at the third detection position 7. The height of the peak here is calculated by the formula H3=H3-H1-H4, where H3 is the peak height corresponding to the third detection position 7.

[0059] The middle value of H1, H2 and H3 is the actual height value of Tin Wave 12 at this time.

[0060] On the basis of any of the above embodiments, after the moving component drives the detection element 4 to move the first distance to the first detection position 5, the control element controls and adjusts the speed of the crest motor 11 until the detection element 4 detects the tin wave 12 signal, and the speed of the crest motor 11 at this time is obtained;

[0061] After the moving component drives the detection element 4 to move the second detection position 6 by the second distance, the control element controls and adjusts the speed of the crest motor 11 until the detection element 4 detects the tin wave 12 signal, and the speed of the crest motor 11 at this time is obtained;

[0062] After the moving component drives the detection element 4 to move the third detection position 7 by the third distance, the control element controls and adjusts the speed of the crest motor 11 until the detection element 4 detects the tin wave 12 signal, and the speed of the crest motor 11 at this time is obtained;

[0063] Compare the three speeds and take the middle value as the motor's operating speed. At this time, the height of the tin wave 12 is the height value that should be set, and the peak height adjustment is completed.

[0064] The first distance, the second distance and the third distance are equal and are the differences among the distance between the detection element 4 and the nozzle 10, the height of the tin furnace 9 and the height value of the tin wave 12.

[0065] In the present embodiment, the first distance, the second distance and the third distance are all H3-H1-H2, wherein H3 is the distance between the detection element 4 and the nozzle 10, H1 is the height of the tin furnace 9, and H2 is the height value of the tin wave 12 to be set.

[0066] On the basis of any of the above embodiments, the moving component drives the detection element 4 to move toward the detection position, and the control component controls the rotation speed of the wave crest motor 11 so that when the detection element 4 contacts the tin surface of the wave crest, the control component controls the moving component to stop, and the height adjustment of the tin wave 12 is completed;

[0067] Or, the moving component drives the detection element to move toward the detection position. When the control component controls the rotation speed of the crest motor 11 so that the detection element 4 has a fourth distance from the tin surface of the crest, the control component controls the moving component to stop and completes the height adjustment of the tin wave 12. The fourth distance is the height value that the tin wave 12 should be set to and the distance that should be set between the detection element 4, which can be 5mm.

[0068] In this embodiment, two detection methods of the wave peak height are described in detail, non-contact type or contact type. Both methods are closed-loop control to ensure reliable and accurate adjustment of the wave peak height.

[0069] In addition, please continue to refer to Figures 4 to 8 , Figure 4The control element in is PLC, and the height measuring element 8 feeds back the height information of the tin furnace 9 to the PLC. The PLC controls the Z-axis moving part 3 to drive the detection element 4 to reach each detection position to obtain the height information of the corresponding wave peak. The displacement information of the Z-axis moving part 3 at each detection position is the height information of the corresponding wave peak at the detection position. The PLC can determine the actual height value of the lower tin wave 12 according to the feedback information of the height measuring element 8 and the Z-axis moving part 3 and judge whether calibration is needed.

[0070] The desired height value of the tin wave 12 is pre-stored in the PLC. According to the difference between the actual height value and the desired height value, the PLC controls the speed of the crest motor to automatically calibrate the actual height of the tin wave 12 to achieve a closed-loop control effect.

[0071] The specific calibration method is to control the wave crest motor by combining "pulse + direction". The PLC sends pulse and direction signals to the core plates corresponding to the wave crest motor 11, the X-axis moving part 1, the Y-axis moving part 2, and the Z-axis moving part 3. The core plate here is Figure 5-Figure 8 The components on the right are further transmitted to the corresponding circuits of the wave crest motor 11, the X-axis moving part 1, the Y-axis moving part 2, and the Z-axis moving part 3 through the core board and the control signal line to realize their driving.

[0072] If any of the wave motor 11, X-axis moving part 1, Y-axis moving part 2, and Z-axis moving part 3 fails, the fault information is transmitted to the PLC through the corresponding core board, and then the PLC sends a fault command to the wave motor 11, X-axis moving part 1, Y-axis moving part 2, and Z-axis moving part 3. The fault command can be a shutdown command or an alarm command, so that the corresponding faulty component stops operating or issues an alarm, etc.

[0073] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0074] The above is a detailed introduction to a wave peak height closed-loop control system provided by the utility model. This article uses specific examples to illustrate the principle and implementation method of the utility model. The description of the above embodiment is only used to help understand the method and core idea of ​​the utility model. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the utility model, the utility model can also be improved and modified, and these improvements and modifications also fall within the scope of protection of the claims of the utility model.

Claims

1. A wave peak height closed-loop control system, characterized in that: include: A tin furnace (9), wherein a nozzle (10) is provided on the top of the tin furnace (9) for wave soldering a workpiece to form a tin wave (12); A detection element (4) is disposed at the upper end of the nozzle (10) and is connected to a moving component, wherein the moving component can drive the detection element (4) to move to a plurality of detection positions on the tin wave (12) to obtain wave peak height information; A control element, the detection element (4) and the moving component are both connected to the control element by signal, the control element is used to control the movement of the moving component to drive the detection element (4) to reach any of the detection positions; A wave crest motor (11) is disposed on one side of the nozzle (10), and the control element is used to receive the height information of the plurality of detection positions and calculate the actual height value of the tin wave (12). The control element can control the rotation speed of the wave crest motor (11) according to the difference between the actual height value and the height value that the tin wave (12) should be set to for automatic calibration.

2. The peak height closed-loop control system according to claim 1, characterized in that: A height measuring element (8) for obtaining the height of the tin furnace (9) is provided on one side thereof, and the control element is used to receive the height information of the tin furnace (9), the moving height information of the detection element (4), and the distance information between the detection element (4) and the nozzle (10) to obtain the peak height information at the detection position.

3. The crest height closed-loop control system according to claim 2, characterized in that: A first detection position (5), a second detection position (6), and a third detection position (7) are respectively arranged along the length direction of the tin wave (12); the first detection position (5) and the third detection position (7) correspond to two ends of the tin wave (12), and the second detection position (6) is arranged in the middle of the tin wave (12).

4. The crest height closed-loop control system according to claim 3, characterized in that: The moving assembly comprises an X-axis moving part (1), a Y-axis moving part (2) and a Z-axis moving part (3); two groups of the X-axis moving parts (1) are arranged in parallel and are both connected to the Y-axis moving part (2); and the Z-axis moving part (3) is connected to the Y-axis moving part (2).

5. The crest height closed-loop control system according to claim 4, characterized in that: The X-axis moving part (1), the Y-axis moving part (2), the Z-axis moving part (3), the wave crest motor (11), and the detection element (4) are all provided with a fault module connected to the control element signal.

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