Welding machine with upper preheating function and lower preheating function

Abstract

The utility model relates to the technical field of circuit board welding, in particular to a welding machine with an upper preheating function and a lower preheating function. The welding machine with the vertical preheating function comprises a conveying device, a scaling powder spraying device, a welding device, a first preheating device and a second preheating device. The conveying device is used for conveying circuit boards; the soldering flux spraying device and the welding device are arranged on the first side of the conveying device; the first preheating device is arranged on the first side of the motion trail of the circuit board, and the first preheating device comprises a first protective cover and a first heating body arranged in the first protective cover; the second preheating device is arranged on the second side of the circuit board motion trail; the second preheating device comprises a second protective cover, a second heating body arranged in the second protective cover and a diathermanous plate arranged on the second protective cover. And after the soldering flux is sprayed, the circuit board is preheated by the first preheating device and the second preheating device, so that the circuit board is at the optimal welding temperature, and the welding quality is better guaranteed.

Description

Technical Field

[0001] This utility model relates to the field of circuit board welding technology, and in particular to a welding machine with upper and lower preheating. Background Technology

[0002] Some components on a circuit board are fixed to the board by soldering. During circuit board soldering, flux is typically applied first, and then the components are soldered to the board. Circuit board soldering equipment is available on the market, but some of these machines typically apply flux before soldering. In this method, the temperature of the flux and the temperature of the circuit board may not be consistent, making it difficult to maintain a consistent soldering temperature and potentially leading to cold solder joints.

[0003] For example, Chinese patent application number CN202120189816.9 discloses a circuit board assembly and welding equipment, which specifically describes "horizontally conveying PCBA boards and FPC boards via a horizontal conveyor line and an FPC board horizontal conveyor line. A board gripping mechanism grips and places the PCBA boards and FPC boards, and a flux spraying mechanism applies flux to the PCBA boards. A visual image correction mechanism determines the position of the circuit board. A rotary table and a welding machine weld the PCBA boards and FPC boards." This type of equipment performs welding immediately after flux spraying, and the temperature may differ from the circuit board temperature. The welding temperature is also difficult to guarantee, potentially leading to cold solder joints.

[0004] For example, Chinese patent application number CN201410475940.6 states that the circuit board soldering device is invalid due to non-payment of annual fees. Similarly, soldering is performed after flux is sprayed, but the temperature may differ from the circuit board temperature, and the soldering temperature is difficult to guarantee, potentially leading to cold solder joints. Utility Model Content

[0005] In view of this, the present invention addresses the deficiencies of the existing technology by providing a welding machine with upper and lower preheating. The machine is preheated after the flux is sprayed and then welded. The welding temperature is controlled, and the welding quality is better guaranteed, thereby overcoming the shortcomings of the existing technology.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] This application provides a welding machine with upper and lower preheating, including a conveying device, a flux spraying device, a welding device, a first preheating device, and a second preheating device; the conveying device is used to convey a circuit board; the flux spraying device and the welding device are disposed on a first side of the conveying device; the first preheating device is disposed on a first side of the circuit board's movement trajectory, and the first preheating device includes a first protective cover and a first heating element disposed within the first protective cover; the second preheating device is disposed on a second side of the circuit board's movement trajectory, and the second preheating device includes a second protective cover, a second heating element disposed within the second protective cover, and a heat-transmitting plate disposed on the second protective cover.

[0008] Preferably, the conveying device includes a sliding module, a lifting module, and a carrier fixture; the lifting module is disposed in the sliding module; the carrier fixture is disposed in the lifting module; wherein, the carrier fixture includes a carrier support, a carrier, an adjusting plate, and an adjusting component; the carrier is slidably disposed in the carrier support; the adjusting plate is adjustablely disposed in the carrier, and the adjusting component is adjustablely disposed in the adjusting plate; the adjusting component clamps the circuit board.

[0009] Preferably, the adjusting plate and the carrier are provided with a narrow first adjusting hole, and a first fastener fixes the adjusting plate to the carrier; the adjusting plate is provided with a narrow second adjusting hole, and a second fastener fixes the adjusting member to the adjusting plate; wherein the adjusting member is L-shaped.

[0010] Preferably, the flux spraying device includes a flux box, a nozzle bracket, and a nozzle; the nozzle bracket is disposed in the flux box, and the nozzle is adjustablely disposed in the nozzle bracket.

[0011] Preferably, the welding device includes a solder pot, a nitrogen hood covering the solder pot, and a solder head connected to the solder pot; the nitrogen hood is equipped with a cooling fan to cool the solder pot; the solder head is fitted with a reflow sleeve, and a reflow channel communicating with the solder pot is formed between the solder head and the reflow sleeve, so that the solder can flow back into the solder pot.

[0012] Preferably, the solder head has a hollow structure inside, which allows solder to be extruded; the annular seat of the nitrogen hood is provided with a plurality of air holes, through which the solder head passes and nitrogen can be discharged.

[0013] Preferably, the first preheating device further includes a first lampshade disposed inside the first protective cover, a first thermocouple thermometer disposed inside the first lampshade, and a first air pipe disposed outside the first heating element; the first air pipe can blow air toward the circuit board.

[0014] Preferably, the second preheating device further includes a second lampshade disposed inside the second protective cover and a second thermocouple thermometer disposed outside the heat-transmitting plate; wherein the second lampshade has a plurality of reflective grooves and the second heating element is disposed in the reflective grooves.

[0015] Preferably, the first heating element is a resistive heating element, and the second heating element is an infrared lamp tube; the reflective groove has an isosceles trapezoidal shape.

[0016] This application provides a circuit board soldering method, including S1, feeding, placing the circuit board into a conveying device;

[0017] S2. Spraying flux: The flux spraying device is located below the conveying device; the conveying device transports the circuit board to the flux spraying device, and the flux spraying device sprays flux onto the circuit board.

[0018] S3. Circuit board preheating: After the circuit board is coated with flux, the conveying device transports the circuit board between the first preheating device and the second preheating device. The first preheating device and the second preheating device preheat the circuit board at the same time.

[0019] S4. Circuit board welding: After the circuit board is preheated, the conveying device transports the circuit board to the welding device, and the welding device welds the circuit board.

[0020] This invention has significant advantages and beneficial effects compared with existing technologies. Specifically, as shown in the above technical solution, the conveying device is used to convey the circuit board, the flux spraying device sprays flux onto the circuit board, and the welding device welds the circuit board. The circuit board is sandwiched between the first preheating device and the second preheating device. After the flux is sprayed, the first and second preheating devices preheat the circuit board, ensuring that the circuit board is at the optimal welding temperature and guaranteeing better welding quality. Attached Figure Description

[0021] Figure 1 This is an overall schematic diagram of an embodiment of the present utility model.

[0022] Figure 2 This is an embodiment of the present utility model. Figure 1 Partial structural diagram.

[0023] Figure 3 This is a schematic diagram of a flux spraying device and a welding device according to an embodiment of the present invention.

[0024] Figure 4 This is a schematic diagram of a conveying device according to an embodiment of the present invention.

[0025] Figure 5 This is an exploded view of the second preheating device according to an embodiment of the present invention.

[0026] Figure 6 This is an exploded view of the first preheating device according to an embodiment of the present invention.

[0027] Figure 7 This is an exploded view of the vehicle tooling according to an embodiment of the present utility model.

[0028] Explanation of reference numerals in the attached diagram:

[0029] 10. Conveying device; 11. Sliding module; 12. Lifting module; 110. Carrier fixture; 111. Carrier support; 112. Carrier; 113. Adjusting plate; 114. Adjusting component; 115. First fastener; 116. Second fastener; 20. Flux spraying device; 21. Flux box; 22. Nozzle support; 23. Nozzle; 30. Welding device; 31. Solder furnace; 32. Nitrogen hood; 33. Annular seat; 34. Vent; 35. Solder tip; 36. Cooling fan; 37. Return sleeve; 40. First preheating device; 41. First protective cover; 42. First lamp cover; 43. First heating element; 44. First thermocouple thermometer; 45. First air pipe; 50. Second preheating device; 51. Second protective cover; 52. Second heating element; 53. Heat-transmitting plate; 54. Second thermocouple thermometer; 55. Reflector groove; 60. Circuit board. Detailed Implementation

[0030] To further illustrate the technical means and effects adopted by this utility model in order to achieve the intended utility model purpose, the following detailed description of the specific implementation methods, structure, features and effects of this utility model is provided in conjunction with the accompanying drawings and preferred embodiments.

[0031] Example 1

[0032] Please refer to Figures 1 to 7 As shown, it illustrates the specific structure of a preferred embodiment of the present invention, which is a welding machine with upper and lower preheating.

[0033] After the circuit board is coated with flux, the first preheating device 40 and the second preheating device 50 preheat the circuit board, so that both the top and bottom surfaces of the circuit board 60 are heated, ensuring better soldering quality and eliminating the problem of cold solder joints.

[0034] This application provides a welding machine with upper and lower preheating, including a conveying device 10, a flux spraying device 20, a welding device 30, a first preheating device 40, and a second preheating device 50. The conveying device 10 is used to convey a circuit board 60. The flux spraying device 20 and the welding device 30 are disposed on the lower side of the conveying device 10. The first preheating device 40 is disposed on the first side of the movement trajectory of the circuit board 60, and includes a first protective cover 41 and a first heating element 43 disposed within the first protective cover 41. The second preheating device 50 is disposed on the second side of the movement trajectory of the circuit board 60, and includes a second protective cover 51, a second heating element 52 disposed within the second protective cover 51, and a heat-transmitting plate 53 disposed on the second protective cover 51. The conveying device 10 is used to convey the circuit board 60, the flux spraying device 20 is used to spray flux onto the circuit board 60, and the welding device 30 is used to weld the circuit board 60. The first preheating device 40 and the second preheating device 50 are used to preheat the circuit board 60. The first preheating device 40 and the second preheating device 50 are arranged alternately. The first preheating device 40 preheats the top surface of the circuit board 60, and the second preheating device 50 preheats the bottom surface of the circuit board 60, ensuring better soldering quality. During production: 1. The circuit board 60 is fed into the conveyor 10. 2. The conveyor 10 conveys the circuit board 60 to the flux spraying device 20, which sprays flux onto the circuit board 60. 3. After the flux is sprayed, the circuit board 60 continues to move between the first preheating device 40 and the second preheating device 50, which preheat the circuit board 60. 4. After the circuit board 60 is preheated, the conveyor 10 conveys the circuit board 60 to the soldering device 30, which solders the circuit board 60. Because the circuit board 60 is preheated before soldering after being sprayed with flux, the soldering quality is better guaranteed.

[0035] The first protective cover 41 concentrates heat, directing it towards the circuit board 60. The first heating element 43 generates heat, preheating the top of the circuit board 60. The second protective cover 51 concentrates heat, directing it towards the circuit board 60. The second heating element 52 generates heat, preheating the bottom of the circuit board 60. The heat-transmitting plate 53 is preferably glass, preventing flux from dripping onto the second heating element 52. The first heating element 43 is preferably an electric heating rod or electric heating wire. The second heating element 52 is preferably an infrared heating lamp.

[0036] Preferably, the conveying device 10 includes a sliding module 11, a lifting module 12, and a carrier fixture 110; the lifting module 12 is disposed on the sliding module 11; the carrier fixture 110 is disposed on the lifting module 12; wherein, the carrier fixture 110 includes a carrier support 111, a carrier 112, an adjusting plate 113, and an adjusting member 114; the carrier 112 is slidably disposed on the carrier support 111; the adjusting plate 113 is adjustablely disposed on the carrier 112, and the adjusting member 114 is adjustablely disposed on the adjusting plate 113; the adjusting member 114 clamps the circuit board 60. The sliding module 11 is preferably a linear module driven by a first servo motor. The lifting module 12 is preferably a lead screw module, driven by a second servo motor for up-and-down movement. The carrier 112 is driven by a third servo motor for movement. Therefore, the coordinated linear movement of the sliding module 11, the lifting module 12, and the carrier fixture 110 enables the circuit board 60 to move in the XYZ directions. The circuit board 60 can move precisely and flexibly to each mechanism to complete the corresponding process. In this embodiment, there are two adjustment plates 113, and each adjustment plate 113 is provided with two adjustment members 114. By adjusting the position of the adjustment plate 113 on the carrier 112 and adjusting the position of the adjustment members 114 on the adjustment plate 113, circuit boards 60 of different sizes can be accommodated, thereby improving the application range of the carrier tooling 110.

[0037] Preferably, the adjusting plate 113 and the carrier 112 are provided with elongated first adjusting holes, and the first fastener 115 fixes the adjusting plate 113 to the carrier 112; the adjusting plate 113 is provided with elongated second adjusting holes, and the second fastener 116 fastens the adjusting member 114 to the adjusting plate 113; wherein, the adjusting member 114 is L-shaped. The first fastener 115 and the second fastener 116 are preferably screws or spring bolts. After loosening the first fastener 115, the position of the adjusting plate 113 on the carrier 112 can be adjusted; after loosening the second fastener 116, the position of the adjusting member 114 on the adjusting plate 113 can be adjusted, which is very convenient to operate.

[0038] Preferably, the flux spraying device 20 includes a flux box 21, a nozzle bracket 22, and a nozzle 23. The nozzle bracket 22 is disposed in the flux box 21, and the nozzle 23 is adjustablely disposed in the nozzle bracket 22. The position of the nozzle 23 in the nozzle bracket 22 is adjusted by screws. This design can adapt to different usage environments and facilitates adjustment of the distance between the sprayed material and the circuit board 60. Excess flux from the nozzle 23 falls into the flux box 21 for reuse, saving flux.

[0039] Preferably, the welding apparatus 30 includes a solder pot 31, a nitrogen hood 32 covering the solder pot 31, and a solder head 35 connected to the solder pot 31. A cooling fan 36 is installed on the nitrogen hood 32 to cool the solder pot 31. A return sleeve 37 is fitted onto the solder head 35, forming a return channel communicating with the solder pot 31 between the solder head 35 and the return sleeve 37, allowing solder to flow back into the solder pot 31. The nitrogen hood 32 is filled with nitrogen. Nitrogen serves as a protective gas, further ensuring the quality of the welding and preventing air from affecting the welding quality. The cooling fan 36 controls the temperature of the solder pot 31, ensuring the solder inside is at the optimal welding temperature. The solder inside the solder pot 31 is pressurized and then soldered from the solder head 35 onto the circuit board 60, resulting in better welding quality.

[0040] Preferably, the solder head 35 has a hollow internal structure, which allows solder to be extruded. The annular seat 33 of the nitrogen shroud 32 has several vents 34, through which the solder head 35 protrudes, allowing nitrogen gas to escape. Molten solder is extruded from the hollow internal structure of the solder head 35 onto the circuit board 60, ensuring higher soldering quality. During soldering, nitrogen gas is ejected from the vents 34 of the annular seat 33, forming a protective layer at the soldering location and further contributing to high-quality soldering.

[0041] Preferably, the first preheating device 40 further includes a first lampshade 42 disposed within the first protective cover 41, a first thermocouple thermometer 44 disposed within the first lampshade 42, and a first air pipe 45 disposed outside the first heating element 43; the air outlet of the first air pipe 45 can blow air towards the circuit board 60. The first lampshade 42 is used to prevent heat loss and control the direction of heat. The first thermocouple thermometer 44 is used to measure temperature. In this embodiment, the first heating element 43 is an electric heating tube. Its heat is transferred to the circuit board 60 through the air to preheat the circuit board 60. The first air pipe 45 is connected to an air pump, and the air outlet of the first air pipe 45 blows air towards the circuit board 60, which can control the temperature of the circuit board 60. If the temperature is too high, air is blown to cool it down.

[0042] Preferably, the second preheating device 50 further includes a second lampshade disposed within the second protective cover 51 and a second thermocouple thermometer 54 disposed outside the heat-transmitting plate 53 (preferably glass); wherein the second lampshade has a plurality of reflective grooves 55, and the second heating element 52 is disposed within the reflective grooves 55. The first heating element 43 is a resistance heating element, and the second heating element 52 is an infrared lamp tube; the reflective grooves 55 have an isosceles trapezoidal shape. The second lampshade is used to prevent heat loss and control the direction of heat. In this embodiment, the second heating element 52 is an infrared heating tube. The second thermocouple thermometer 54 is used to measure temperature and prevent the circuit board 60 from overheating. The reflective grooves 55 have an isosceles trapezoidal shape, which allows the heat from the second heating element 52 to be transferred to the circuit board 60 more evenly.

[0043] Example 2

[0044] This application provides a circuit board soldering method, including S1, feeding, in which a circuit board 60 is placed into a conveying device 10. An adjusting member 114 clamps the circuit board 60, and then the conveying device 10 conveys the circuit board 60.

[0045] S2. Applying flux: The flux application device 20 is located below the conveying device 10. The conveying device 10 transports the circuit board 60 to the flux application device 20, which then applies flux to the circuit board 60. In this embodiment, the circuit board 60 is soldered using wave soldering. The flux application pressure is controlled at 0.2–0.3 MPa, which helps ensure the quality of the flux application.

[0046] S3. Circuit board 60 preheating: After flux is sprayed onto circuit board 60, the conveying device 10 transports circuit board 60 between the first preheating device 40 and the second preheating device 50. The first preheating device 40 and the second preheating device 50 simultaneously preheat circuit board 60. In this embodiment, the preheating temperature of circuit board 60 is between 370-300 degrees Celsius, preferably 280 degrees Celsius. During preheating, ensure that the solder joint temperature is 50 degrees Celsius higher than the melting point of the solder to achieve a reliable soldering effect.

[0047] S4. Soldering of circuit board 60: After preheating, the conveying device 10 transports circuit board 60 to the soldering device 30, which then solders the circuit board 60. After preheating, the soldering device 30 applies solder to the solder joints, completing the soldering process.

[0048] S5. Remove circuit board 60; remove circuit board 60 manually or with a robotic arm.

[0049] In summary, the key design feature of this utility model is that after the flux is sprayed, the first preheating device 40 and the second preheating device 50 preheat the circuit board 60, so that the circuit board 60 is at the optimal soldering temperature, and the soldering quality is better guaranteed.

[0050] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Although the present utility model has been disclosed above with reference to a preferred embodiment, it is not intended to limit the present utility model. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present utility model. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present utility model without departing from the scope of the present utility model shall still fall within the scope of the present utility model.

Claims

1. A welding machine with upper and lower preheating, characterized in that: The device comprises a conveying device, a flux spraying device, a welding device, a first preheating device, and a second preheating device. The conveying device is used for conveying the circuit board. The flux spraying device and the welding device are arranged beside the conveying device. The first preheating device is arranged on the first side of the movement track of the circuit board. The first preheating device comprises a first protective cover and a first heating body arranged in the first protective cover.

2. A welding machine with upper and lower preheating according to claim 1, characterized in that: The second preheating device is arranged on the second side of the movement track of the circuit board.

3. The welding machine with upper and lower preheating according to claim 1, characterized in that: The second preheating device comprises a second protective cover, a second heating body arranged in the second protective cover, and a heat-permeable plate arranged on the second protective cover.

4. The welding machine with upper and lower preheating according to claim 1, characterized in that: The conveying device comprises a sliding module, a jacking module, and a carrier tool.

5. A welding machine with upper and lower preheating according to claim 4, characterized in that: The jacking module is arranged on the sliding module.

6. The welding machine with upper and lower preheating of claim 1, wherein: The carrier tool is arranged on the jacking module.

7. A welding machine with upper and lower preheating according to claim 6, characterized in that: The carrier tool comprises a carrier support, a carrier, an adjusting plate, and an adjusting member.

8. A welding machine with upper and lower preheating according to claim 6, characterized in that: The carrier is slidingly arranged on the carrier support. The adjusting plate is adjustably arranged on the carrier. The adjusting member is adjustably arranged on the adjusting plate. The adjusting member is L-shaped. The flux spraying device comprises a flux box, a nozzle support, and a nozzle. The nozzle support is arranged on the flux box. The nozzle is adjustably arranged on the nozzle support. The welding device comprises a tin furnace, a nitrogen cover arranged on the tin furnace, and a soldering head connected to the tin furnace. The nitrogen cover is provided with a cooling fan for cooling the tin furnace. The soldering head is provided with a reflow sleeve. The soldering head and the reflow sleeve form a reflow channel connected to the tin furnace. The soldering head is hollow and can extrude solder. The nitrogen cover is provided with a plurality of air holes. The soldering head passes through the air holes. The first preheating device further comprises a first lamp cover arranged in the first protective cover, a first thermocouple temperature gauge arranged on the first lamp cover, and a first air pipe arranged on the outside of the first heating body. The first air pipe can blow air towards the circuit board. The second preheating device further comprises a second lamp cover arranged in the second protective cover and a second thermocouple temperature gauge arranged on the outside of the heat-permeable plate. The second lamp cover has a plurality of reflection grooves. The second heating body is arranged in the reflection grooves. The first heating body is an electric resistance heating body. The second heating body is an infrared lamp tube. The reflection grooves have an isosceles trapezoidal shape.

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