A reflow soldering device and method for SMT

Abstract

The present invention belongs to the technical field of SMT reflow soldering, and specifically relates to a reflow soldering device and method for SMT; it comprises a reflow soldering furnace and a steel mesh; a telescopic cylinder is arranged on the side of the reflow soldering furnace, a U-shaped substrate is installed on the output end of the telescopic cylinder, a guide rail is arranged on the opposite surface of the U-shaped substrate, and printing equipment is slidably arranged on the guide rail; a locking actuator component is also arranged on the U-shaped substrate; the locking actuator component comprises a rectangular frame, and the steel mesh is located in the rectangular frame; a T-shaped clamp is installed on the outer wall of the rectangular frame, a take-up roller is installed at the interlayer of the T-shaped clamp, and an energy dissipation and anti-movement mechanism is arranged on the take-up roller; different types of steel meshes required for printing can be quickly replaced by the locking actuator component, so that different types of PCB boards can be printed using matching steel meshes, thereby improving the reflow soldering effect of the device on the SMT board, thereby reducing the limitations of the device when in use.

Description

Technical Field

[0001] The invention belongs to the technical field of SMT reflow soldering, and specifically relates to a reflow soldering device and method for SMT. Background Art

[0002] SMT reflow soldering is a welding technology that re-melts the paste solder pre-distributed to the pads of the printed circuit board (PCB) to achieve reliable electrical and mechanical connections between the pins or endpoints of the surface mounted components and the corresponding pads on the PCB. During the reflow soldering of the SMT board, the SMT board needs to be placed on the conveyor belt of the reflow soldering furnace, and then the solder paste on the SMT board is melted and cooled through the constant temperature zone, high temperature zone, and cooling zone. However, before this, the solder paste needs to be printed on the pads of the PCB board through a steel mesh, and the components are placed on the pads at the corresponding positions. Finally, the PCB board with components, that is, the SMT board, is placed in the above position for reflow soldering.

[0003] The existing reflow soldering device for SMT cannot quickly replace the steel mesh required for printing solder paste according to the component packaging type (such as fine-pitch components, larger-sized components) or PCB board design requirements (such as circuit density, special area design) during use, so that the solder paste required for PCB board welding cannot reach the appropriate dosage according to the design requirements. The overflow or lack of solder paste printed on the PCB board pad will affect the reflow soldering effect of the device, which makes the device have strong limitations when used. Summary of the invention

[0004] In view of the above situation, in order to overcome the defects of the prior art, the present invention provides a reflow soldering device and method for SMT, which effectively solves the problems in the above background technology.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a reflow soldering device for SMT, comprising a reflow soldering furnace and a steel mesh; a telescopic cylinder is provided on the side of the reflow soldering furnace, a U-shaped substrate is installed on the output end of the telescopic cylinder, a guide rail is provided on the opposite surface of the U-shaped substrate, and a printing device is slidably provided on the guide rail; a locking actuator component is also provided on the U-shaped substrate, and the locking actuator component is used for the operation of installing / disassembling the steel mesh; the locking actuator component comprises a rectangular frame, and the steel mesh is located in the rectangular frame; a T-shaped clip is installed on the outer wall of the rectangular frame The U-shaped base plate is a T-shaped clamping plate, and a wire-receiving roller is installed at the interlayer of the T-shaped clamping plate. The wire-receiving roller is provided with an energy dissipation and anti-movement mechanism, which can prevent the steel mesh from shaking during the solder paste printing process on the pads on the PCB board; a telescopic square column is installed on all four sides of the top of the rectangular frame, and several telescopic square columns are connected to the U-shaped base plate; a retaining T-plate is installed at the outer side wall of the rectangular frame away from the T-shaped clamping plate, and a driving gear is rotatably connected to the retaining T-plate; an engaging and fixing unit is also provided on the retaining T-plate, and the engaging and fixing unit is used to limit the driving gear.

[0006] Preferably, a first base plate is installed on the top and bottom of the fixed T-plate, and a movable sliding column is slidably connected to the two first base plates. A movable square plate is installed at both ends of the two movable sliding columns. The two movable square plates on one movable sliding column are commonly connected to a movable rack, and the two movable racks are meshed with the driving gear; a movable spring is sleeved on the movable sliding column, one end of the movable spring is connected to the movable square plate, and the other end is connected to the first base plate.

[0007] Preferably, one end of a bent square rod is installed on a movable square plate on the two movable racks, and the other end of the bent square rod is located in the rectangular frame and is installed with a movable cross plate, and the two movable cross plates are symmetrically arranged; two symmetrically arranged locking slides are penetrated on the opposite surfaces of the two movable cross plates, and the locking slides slide in sliding cooperation with the movable cross plate; a movable limit plate is provided at one end of the locking slide close to the inner wall of the rectangular frame; the two locking slides on one of the movable cross plates are connected to a locking long block at one end away from the movable limit plate, and rubber pads are provided on the opposite surfaces of the two locking long blocks, and the side surface of the steel mesh is located on the moving path of the rubber pad; a locking spring is sleeved on the locking slide, one end of the locking spring is connected to the locking long block, and the other end is connected to the movable cross plate.

[0008] Preferably, the energy dissipation and anti-movement mechanism includes a fixing square seat arranged on the bent square rod; a fixed pulley is installed on the side of the T-shaped clamp away from the wire-taking roller, and the fixed pulley is located in the interlayer of the T-shaped clamp; the fixed pulley and the wire-taking roller are symmetrically arranged, and the fixing square seat is located between the fixed pulley and the wire-taking roller; one end of the cable is installed on the fixing square seat, and the other end of the cable is wrapped around the fixed pulley and connected to the wire-taking roller; displacement screws are installed on the top and bottom of the wire-taking roller, and the two displacement screws are symmetrically arranged and have opposite threads; a clockwork spring is installed on the displacement screw, and the end point of the clockwork spring is connected to the T-shaped clamp; displacement blocks are threadedly connected to the two displacement screws, and a guide square plate is installed on the side of the displacement block, and a guide cylinder is slidably connected to the guide square plate, and the guide cylinder is arranged on the T-shaped clamp.

[0009] Preferably, a Z-shaped square plate is installed on the side of the displacement block away from the guide square plate, and an equidistant frame is installed on the Z-shaped square plate, and the two equidistant frames are respectively located at the top and bottom of the steel mesh; guide slide rods are arranged on all four sides of the top of the equidistant frame, and the guide slide rods slide in cooperation with the equidistant frames; a guide limit plate is connected to the end of the guide slide rod away from the steel mesh; a guide spring is sleeved on the guide slide rod, one end of the guide spring is connected to the guide limit plate, and the other end is connected to the equidistant frame; a buffer circular pad is installed at the end of the guide slide rod close to the steel mesh.

[0010] Preferably, the engaging and rotating unit includes two second base plates symmetrically arranged on the side of the fixing T-plate away from the T-shaped clamp, and positioning square columns are installed on the opposite surfaces of the two second base plates, and a positioning square block is slidably connected to the positioning square column, and a positioning cross plate is provided on the side of the positioning block away from the T-shaped clamp, and a positioning cylinder is slidably connected to the positioning cross plate, one end of the positioning cylinder is connected to a positioning limit plate, and the other end is connected to a positioning tooth block, and the driving gear is located on the moving path of the positioning tooth block and the two are meshed; a positioning spring is sleeved on the positioning cylinder, one end of the positioning spring is connected to the positioning limit plate, and the other end is connected to the positioning cross plate; an auxiliary spring is sleeved on the positioning square column, one end of the auxiliary spring is connected to the positioning block, and the other end is connected to the auxiliary limit plate, and the auxiliary limit plate is arranged on the end of the positioning square column away from the second base plate.

[0011] Preferably, storage square grooves are provided on the inner opposite surfaces of the positioning block, and a self-locking bevel block is slidably provided in the storage square grooves; a plurality of self-locking bevel grooves are provided on the top and bottom of the positioning square column, and part of the self-locking bevel block is located in the self-locking bevel grooves. When the positioning block moves toward the direction of the driving gear with the self-locking bevel block, the inclined surface on the self-locking bevel block will fit with the inclined surface on the self-locking bevel groove; a self-locking cylinder is installed on the side of the self-locking bevel block away from the self-locking bevel groove, the self-locking cylinder passes through the positioning block and the two are slidably connected; a self-locking spring is sleeved on the self-locking cylinder, one end of the self-locking spring is connected to the positioning block, and the other end is connected to a self-locking limit plate, and the self-locking limit plate is arranged on the end of the self-locking cylinder away from the positioning block.

[0012] Preferably, a re-scraping cleaning component is also provided on the equidistant frame; the re-scraping cleaning component includes a re-movable base plate arranged on one side of the top of the equidistant frame, a re-movable square column passes through and is slidably connected to the re-movable base plate, one end of the re-movable square column is connected to a re-movable limit plate, and the other end is connected to the re-movable square plate, a scraping block is installed on the re-movable square plate, and the scraping block is in contact with the steel mesh; suction equipment is also installed on both sides of the scraping block, and the output end of the suction equipment faces the steel mesh; a re-movable spring is sleeved on the re-movable square column, one end of the re-movable spring is connected to the re-movable base plate, and the other end is connected to the re-movable limit plate; an active contact block is installed on the re-movable limit plate.

[0013] Preferably, a rotating disc is rotatably mounted on the fixed pulley, a rotating cylinder is also mounted on the side of the rotating disc away from the fixed pulley, a rotating cross block is slidably connected to the rotating cylinder, two limiting cylinders are symmetrically mounted on one side of the rotating cross block, the two limiting cylinders are slidably connected to a limiting substrate, and the limiting substrate is arranged on a T-shaped clamp; a driven contact block is mounted on the other side of the rotating cross block, and the active contact block is located on the moving path of the driven contact block.

[0014] The present invention also provides a reflow soldering method for SMT, comprising the following steps:

[0015] S001. Place the steel mesh required for printing during reflow soldering in a rectangular frame, and complete the installation of the steel mesh by locking the actuator assembly;

[0016] S002, print solder paste on the pads of the PCB board through the steel mesh, and place the components to be soldered in the area to make an SMT board;

[0017] S003. Place the SMT board on the conveyor belt of the reflow oven. The different temperature zones inside can complete the reflow operation of the SMT board, thereby fixing the components on the PCB board.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] (1) By locking the actuator, different types of steel meshes required for printing can be quickly replaced, so that the appropriate dosage can be used according to the needs during the reflow soldering of the PCB board, avoiding the overflow or lack of solder paste on the pads on the PCB board when printing through the steel mesh, so that different types of PCB boards can be printed using matching steel meshes, thereby improving the reflow soldering effect of the device on the SMT board; and when installing and removing the steel mesh, the operation can be completed without the help of any tools, avoiding the inability to load and unload the steel mesh due to the lack of handy tools during use, reducing the limitations of the device during use and improving the use effect of the device;

[0020] (2) When the positioning block wants to move away from the driving gear, the right-angled surface on the self-locking inclined groove contacts the right-angled surface on the self-locking inclined block, thereby limiting the self-locking inclined block in the self-locking inclined groove, thereby limiting the positioning block so that the positioning block cannot move. Only by manually pulling the self-locking inclined block outward so that it is no longer in the self-locking inclined groove can the positioning tooth block move away from the driving gear, so that the positioning block can only move in one direction, and the moving direction is also limited to moving only toward the driving gear, thereby preventing the positioning tooth block from moving due to non-human factors during use, so that the positioning tooth block is no longer connected to the driving gear, thereby improving the safety of the device during use, and preventing the locking actuator from being dislocated due to non-human factors when installing the steel mesh, thereby improving the use effect of the device;

[0021] (3) The equidistant frame drives the buffer pad to move under the action of the guide slide rod and the guide spring, so that the buffer pads around the top and bottom of the steel mesh move toward the direction of the steel mesh and contact it, thereby setting the limit around the steel mesh to prevent the steel mesh from being dislocated or shaking during use, so that the contact between the steel mesh and the pad area on the PCB board is accurate, avoiding the difference in connection between the two resulting in the solder paste not being able to be completely applied to the pad of the PCB board, thereby improving the use effect of the device; at the same time, the top and bottom of the steel mesh are limited around to avoid the locking long block on the locking actuator assembly from being locked when the steel mesh is installed. Excessive clamping force can cause the steel mesh to warp or deform, so the clamping force can be evenly distributed on the steel mesh, which increases the service life of the steel mesh and the loading and unloading and use effects, reduces the limitations of the device during use, and enables the steel mesh to accurately contact the pad area on the PCB board, improving the welding effect of the device; at the same time, the buffering performance brought by the buffer round pad and the guide spring can reduce the impact force generated by the steel mesh when printing solder paste on the pad and the impact force generated by the shaking of the steel mesh due to external non-human factors, thereby improving the stability of the steel mesh during use and further improving the reflow soldering effect of the device on the SMT board;

[0022] The two locking blocks are moved toward the side of the steel mesh, thereby clamping the steel mesh in the current position and completing the installation of the steel mesh. It is worth mentioning that the rubber pads on the locking blocks can increase the friction between the locking blocks and the steel mesh when they are in contact, thereby preventing the steel mesh from being dislocated during installation. At the same time, after the locking blocks are in contact with the steel mesh, the locking blocks continue to move the locking blocks to the upper limit of the locking slide column, so that the locking spring is in a buffering state, further improving the connection strength between the steel mesh and the locking blocks, preventing the steel mesh from shaking or dislocating during installation and use, and further improving the installation effect of the steel mesh. The buffering property brought by the rubber pads and the locking springs can reduce the impact force on the steel mesh during use, thereby improving the stability of the steel mesh during use, thereby preventing the steel mesh from shaking during printing, resulting in the solder paste being unable to be accurately printed on every pad on the PCB board, thereby improving the use efficiency of the device.

[0023] (5) The scraper block moves back and forth on the surface of the steel mesh, so that the impurities adsorbed and adhered to the surface of the steel mesh can be cleaned during the installation process, so as to avoid the presence of these impurities affecting the printing effect of the solder paste, so that the solder paste is unqualified when it is printed on the pads on the PCB board through the steel mesh, thereby avoiding the presence of these impurities affecting the effect of the components installed on the pads during the reflow soldering process, thereby improving the reflow soldering effect of the device on SMT; at the same time, when the steel mesh is removed, the fixed pulley will be reset and rotated, and the rotating horizontal block will also move back and forth, so that the driven contact block continues to contact the active contact block, so that the scraper block still moves back and forth on its surface during the removal of the steel mesh, thereby cleaning the solder paste adhered to the steel mesh during the printing process, avoiding the need for manual cleaning by the staff, reducing the intensity of the staff, and improving the use effect of the device; at the same time, by using the suction equipment, the suction force generated acts on the holes on the steel mesh, which can clean the residual solder paste in the holes of the steel mesh, improving the cleaning effect of the steel mesh, and further reducing the limitations of the device during use;

[0024] (6) Since the strength of the auxiliary spring is greater than the sum of the self-locking spring and the auxiliary spring, the auxiliary spring drives the positioning block to reset and then reset it on the positioning column, thereby driving the positioning tooth block to reset and move it in the direction of the driving gear, so that the driving gear engages with the positioning tooth block, thereby limiting the driving gear to prevent the driving gear from rotating due to non-human factors during use, thereby further improving the installation effect of the locking actuator on the steel mesh and preventing the steel mesh from dislocating during use; at the same time, the strength of the auxiliary spring causes pressure to act on the positioning cross plate, and since the positioning tooth block has been limited The position cannot be moved, so the positioning cross plate moves within the upper limit of the positioning cylinder, so that the auxiliary spring is in a buffer state, thereby strengthening the connection strength of the positioning tooth block to the driving gear, and further improving the limiting effect of the driving gear; at the same time, when the driving gear is limited, the positioning spring in the buffer state cannot be reset, and the elastic force caused by the inability to reset acts on the driving gear through the positioning rack. Since the driving gear cannot rotate, the meshing strength between the driving gear and the positioning tooth block is strengthened, so that the positioning tooth block cannot be moved due to non-human factors, thereby improving the use effect of the device and reducing the limitations of the device during use. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention.

[0026] In the attached picture:

[0027] Figure 1 This is one of the overall structural schematic diagrams of the present invention;

[0028] Figure 2 This is a schematic diagram of the U-shaped substrate structure of the present invention;

[0029] Figure 3 This is a schematic diagram of the driving gear structure of the present invention;

[0030] Figure 4 This is a schematic diagram of the structure of the rotating disc of the present invention;

[0031] Figure 5 This is the second schematic diagram of the overall structure of the present invention;

[0032] Figure 6 This is a schematic diagram of the structure of the movable horizontal plate of the present invention;

[0033] Figure 7 This is a schematic diagram of the positioning gear block structure of the present invention;

[0034] Figure 8 This is a schematic diagram of the structure of the scraping block of the present invention;

[0035] Fig. 9This is a schematic diagram of the locking long block structure of the present invention;

[0036] Fig.10 It is a cross-sectional view of the positioning block of the present invention;

[0037] Fig.11 This is a schematic diagram of the structure of the buffer circular pad of the present invention;

[0038] In the figure: 1. reflow oven; 2. telescopic cylinder; 3. U-shaped substrate; 4. printing equipment; 5. rectangular frame; 6. T-shaped clamp; 7. take-up roller; 8. telescopic column; 9. fixed T-plate; 10. driving gear; 11. first substrate; 12. movable slide column; 13. movable square plate; 14. movable rack; 15. movable spring; 16. bending square rod; 17. movable horizontal plate; 18. locking slide column; 19. locking long block; 20. rubber pad; 21. locking spring; 22. fixed square seat; 23. fixed pulley; 24. cable; 25. displacement screw rod; 26. spring spring; 27. displacement block; 28. guide square plate; 29. ​​guide cylinder; 30. Z-shaped square plate; 31. equidistant frame; 32. guide slide rod; 33. guide limit plate; 3 4. Guide spring; 35. Buffer pad; 36. Second base plate; 37. Positioning square column; 38. Positioning square block; 39. Positioning horizontal plate; 40. Positioning cylinder; 41. Positioning limit plate; 42. Positioning tooth block; 43. Positioning spring; 44. Auxiliary spring; 45. Auxiliary limit plate; 46. Storage square groove; 47. Self-locking inclined block; 48. Self-locking inclined groove; 49. Self-locking cylinder; 50. Self-locking spring; 51. Self-locking limit plate; 52. Double-acting base plate; 53. Double-acting square column; 54. Double-acting limit plate; 55. Double-acting square plate; 56. Scraping block; 57. Suction device; 58. Double-acting spring; 59. Active contact block; 60. Rotating disk; 61. Rotating cylinder; 62. Rotating horizontal block; 63. Limiting cylinder; 64. Limiting base plate; 65. Driven contact block. DETAILED DESCRIPTION

[0039] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0040] Example, by Figures 1 to 11The present invention comprises a reflow soldering furnace 1 and a steel mesh; a telescopic cylinder 2 is provided on the side of the reflow soldering furnace 1, a U-shaped base plate 3 is installed on the output end of the telescopic cylinder 2, a guide rail is provided on the opposite surface of the U-shaped base plate 3, and a printing device 4 is slidably provided on the guide rail; a locking actuator component is also provided on the U-shaped base plate 3, and the locking actuator component is used for the installation / disassembly operation of the steel mesh; the locking actuator component comprises a rectangular frame 5, and the steel mesh is located in the rectangular frame 5; a T-shaped clamp plate 6 is installed on the outer wall of the rectangular frame 5, and a take-up roller 7 is installed at the interlayer of the T-shaped clamp plate 6, and an energy dissipation and anti-movement mechanism is provided on the take-up roller 7, and the energy dissipation and anti-movement mechanism is obtained. To prevent the steel mesh from shaking during the solder paste printing process on the pads on the PCB board; a telescopic square column 8 is installed on all four sides of the top of the rectangular frame 5, and several telescopic square columns 8 are connected to the U-shaped base plate 3; a fixed T-plate 9 is installed on the outer side wall of the rectangular frame 5 away from the T-shaped clamping plate 6, and a driving gear 10 is rotatably connected to the fixed T-plate 9; a meshing fixed rotation unit is also provided on the fixed T-plate 9, and the meshing fixed rotation unit is used to limit the driving gear 10; a first base plate 11 is installed on the top and bottom of the fixed T-plate 9, and a movable sliding column 12 is slidably connected to the two first base plates 11. A movable square plate 13 is installed at both ends of each movable sliding column 12, and the two movable square plates 13 on one movable sliding column 12 are commonly connected to a movable rack 14, and the two movable racks 14 are meshed and connected with the driving gear 10; a movable spring 15 is sleeved on the movable sliding column 12, one end of the movable spring 15 is connected to the movable square plate 13, and the other end is connected to the first base plate 11; one end of a bent square rod 16 is installed on one movable square plate 13 on the two movable racks 14, and the other end of the bent square rod 16 is located in the rectangular frame 5 and is installed with a movable cross plate 17, and the two movable cross plates 17 are symmetrically arranged; the two movable cross plates 17 are symmetrically arranged; Two symmetrically arranged locking slides 18 are provided through the opposite surfaces of the movable cross plate 17, and the locking slides 18 are slidably matched with the movable cross plate 17; one end of the locking slide 18 close to the inner wall of the rectangular frame 5 is provided with a movable limit plate; one end of the two locking slides 18 on the movable cross plate 17 away from the movable limit plate is commonly connected to a locking long block 19, and the opposite surfaces of the two locking long blocks 19 are provided with rubber pads 20, and the side surface of the steel mesh is located on the moving path of the rubber pad 20; a locking spring 21 is sleeved on the locking slide 18, one end of the locking spring 21 is connected to the locking long block 19, and the other end is connected to the movable cross plate 17;

[0041] Before reflow soldering of the SMT board, solder paste needs to be printed on the pads of the PCB board to place the required electronic components in the area to form an SMT board and put it into the conveyor belt on the reflow soldering furnace 1 to complete the reflow soldering operation of the SMT board. However, during printing, a steel mesh is used as a medium to be placed on the pads of the PCB board. Due to the different design requirements of the PCB board and the packaging types of the components, it is necessary to select a suitable steel mesh according to the situation; by placing the selected suitable steel mesh in the rectangular frame 5, by rotating the driving gear 10, the two movable racks 14 are meshed and moved, and the movable racks 14 are moved to the upper limit position on the first substrate 11 through the movable slide 12, so that the movable spring 15 is in a buffering state, so that when it is reset, it does not need to manually rotate the driving gear 10 to drive the movable rack 14 to reset and move, thereby reducing the work intensity of the staff; thereby, the two movable racks 14 are relatively moved, and the two movable cross plates 17 are relatively moved under the action of the bent square rod 16, so that the two movable racks 14 are relatively moved under the action of the locking slide 18 and the locking spring 21. The locking long block 19 is driven to move relative to each other, and the two locking long blocks 19 are moved toward the side of the steel mesh, so that the steel mesh is clamped in the current position to complete the installation operation of the steel mesh; it is worth mentioning that the rubber pad 20 provided on the locking long block 19 can increase the friction between the locking long block 19 and the steel mesh when in contact, so as to avoid the steel mesh from being dislocated during installation. At the same time, when the locking long block 19 contacts the steel mesh, the movable cross plate 17 is continuously moved to move the locking slide column 18 to move the locking spring 21 in a buffering state, further improving the connection strength between the steel mesh and the locking long block 19, avoiding the steel mesh from shaking or dislocating during installation and use, further improving the installation effect of the steel mesh, and the buffering brought by the rubber pad 20 and the locking spring 21 can reduce the impact force on the steel mesh when in use, improve the stability of the steel mesh when in use, thereby avoiding the shaking of the steel mesh during printing, resulting in the solder paste being unable to be accurately printed on every pad on the PCB board, and improving the use effect of the device;

[0042] When the steel mesh needs to be replaced or maintained, the steel mesh needs to be disassembled. At this time, the limit setting of the driving gear 10 is released and no force is applied to it, so that the positioning spring 15 is no longer limited. The positioning spring 15 is reset to drive the two positioning cross plates 17 to reset and move, so that the two locking long blocks 19 move away from each other, so that no pressure is applied to the two sides of the steel mesh, and the limit setting of the steel mesh is released, thereby completing the disassembly operation of the steel mesh. The disassembly of the steel mesh can be completed without the operation of the staff, which reduces the strength of the staff and further improves the installation and disassembly effect of the device on the steel mesh. , it is possible to quickly replace different types of steel meshes required for printing, so that the PCB board can use the appropriate dosage according to the needs during reflow soldering, avoiding solder paste overflow or lack of solder paste on the pads on the PCB board when printing through the steel mesh, so that different types of PCB boards can be printed using matching steel meshes, thereby improving the reflow soldering effect of the device on the SMT board; and when installing and disassembling the steel mesh, the operation can be completed without the help of any tools, avoiding the inability to load and unload the steel mesh due to the lack of suitable tools during use, reducing the limitations of the device during use and improving the use effect of the device.

[0043] The energy dissipation and anti-movement mechanism of this embodiment includes a fixing square seat 22 arranged on the bent square rod 16; a fixed pulley 23 is installed on the side of the T-shaped clamp plate 6 away from the take-up roller 7, and the fixed pulley 23 is located at the interlayer of the T-shaped clamp plate 6; the fixed pulley 23 and the take-up roller 7 are symmetrically arranged, and the fixing square seat 22 is located between the fixed pulley 23 and the take-up roller 7; one end of the cable 24 is installed on the fixing square seat 22, and the other end of the cable 24 is wound around the fixed pulley 23 and connected with the take-up roller 7; displacement screw rods 25 are installed on the top and bottom of the take-up roller 7, and the two displacement screw rods 25 are symmetrically arranged and have opposite threads; a clockwork spring 26 is installed on the displacement screw rod 25, and the end point of the clockwork spring 26 is connected to the T-shaped clamp plate 6; the two displacement screw rods 25 are threadedly connected with displacement blocks 27, and the displacement blocks 2 A guide square plate 28 is installed on the side of 7, and a guide cylinder 29 is slidably connected to the guide square plate 28, and the guide cylinder 29 is arranged on the T-shaped clamping plate 6; a Z-shaped square plate 30 is also installed on the side of the displacement block 27 away from the guide square plate 28, and an equidistant frame 31 is installed on the Z-shaped square plate 30, and the two equidistant frames 31 are respectively located at the top and bottom of the steel mesh; a guide slide bar 32 is penetrated and arranged around the top of the equidistant frame 31, and the guide slide bar 32 is slidably matched with the equidistant frame 31; a guide limit plate 33 is connected to the end of the guide slide bar 32 away from the steel mesh; a guide spring 34 is sleeved on the guide slide bar 32, one end of the guide spring 34 is connected to the guide limit plate 33, and the other end is connected to the equidistant frame 31; a buffer round pad 35 is installed at the end of the guide slide bar 32 close to the steel mesh;

[0044] The bending square rod 16 drives the fixing square seat 22 to move, so that the take-up roller 7 is rotated under the action of the cable 24 and the fixed pulley 23, so that the two displacement screw rods 25 are rotated, and the spring spring 26 on them is in a buffering state, so that the cable 24 can be reeled and recovered when it is reset; because the threads at the two displacement screw rods 25 are opposite, the two displacement blocks 27 connected by threads are relatively limited and moved, and under the action of the Z-shaped square plate 30, the two equidistant frames 31 are relatively moved, so that under the action of the guide slide rod 32 and the guide spring 34, the buffer circular pads 35 are driven to move, so that the buffer circular pads 35 around the top and bottom of the steel mesh are all moved toward the direction of the steel mesh and contact, so that the limit settings around the steel mesh are set to avoid the steel mesh from being dislocated or shaking during use, so that the contact of each part when the steel mesh contacts the pad area on the PCB board is accurate, avoiding the two The connection phase difference causes the solder paste to be unable to be completely applied to the pads of the PCB board, thereby improving the use effect of the device; at the same time, the top and bottom of the steel mesh are limited to prevent the locking long block 19 on the locking actuator from causing the steel mesh to tilt or deform due to excessive clamping force when the steel mesh is installed, so that the clamping force can be evenly distributed on the steel mesh, thereby improving the service life of the steel mesh as well as the loading and unloading and use effects, reducing the limitations of the device during use, and at the same time allowing the steel mesh to accurately contact the pad area on the PCB board, thereby improving the welding effect of the device; at the same time, the buffering performance brought by the buffer round pad 35 and the guide spring 34 can reduce the impact force generated by the steel mesh when printing the solder paste on the pad and the impact force generated when the steel mesh shakes due to external non-human factors, thereby improving the stability of the steel mesh during use, and further improving the reflow soldering effect of the device on the SMT board.

[0045] The engaging and rotating unit of the present embodiment includes two second base plates 36 symmetrically arranged on the side of the retaining T-plate 9 away from the T-shaped clamping plate 6, and positioning square columns 37 are installed on the opposite surfaces of the two second base plates 36. A positioning block 38 is slidably connected to the positioning square column 37, and a positioning horizontal plate 39 is provided on the side of the positioning block 38 away from the T-shaped clamping plate 6. A positioning cylinder 40 is slidably connected to the positioning horizontal plate 39, one end of the positioning cylinder 40 is connected to a positioning limit plate 41, and the other end is connected to a positioning tooth block 42. The driving gear 10 is located on the moving path of the positioning tooth block 42 and the two are meshed; a positioning spring 43 is sleeved on the positioning cylinder 40, one end of the positioning spring 43 is connected to the positioning limit plate 41, and the other end is connected to the positioning horizontal plate 39; an auxiliary spring 44 is sleeved on the positioning square column 37, one end of the auxiliary spring 44 is connected to the positioning block 38, and the other end is connected to an auxiliary limit plate 45, and the auxiliary limit plate 45 It is arranged on the end of the positioning square column 37 away from the second base plate 36; the inner opposite surfaces of the positioning block 38 are provided with storage square grooves 46, and a self-locking inclined block 47 is slidably arranged in the storage square groove 46; the top and bottom of the positioning square column 37 are provided with a plurality of self-locking inclined grooves 48, and a partial area of ​​the self-locking inclined block 47 is located in the self-locking inclined groove 48. When the positioning block 38 moves with the self-locking inclined block 47 toward the direction of the driving gear 10, the inclined surface on the self-locking inclined block 47 will fit with the inclined surface on the self-locking inclined groove 48; a self-locking cylinder 49 is installed on the side of the self-locking inclined block 47 away from the self-locking inclined groove 48, and the self-locking cylinder 49 passes through the positioning block 38 and the two are slidably connected; a self-locking spring 50 is sleeved on the self-locking cylinder 49, one end of the self-locking spring 50 is connected to the positioning block 38, and the other end is connected to a self-locking limit plate 51, and the self-locking limit plate 51 is arranged on the end of the self-locking cylinder 49 away from the positioning block 38;

[0046] When operating the locking actuator to load and unload the steel mesh, the meshing fixed rotation unit is operated to release the limit setting of the driving gear 10, so that the driving gear 10 can rotate normally, and the locking actuator can be operated to install or disassemble the steel mesh; when the loading and unloading operation of the steel mesh is completed, pressure is no longer applied to the positioning block 38, so that the auxiliary spring 44 is reset. Since the strength of the auxiliary spring 44 is greater than the sum of the self-locking spring 50 and the auxiliary spring 44, the auxiliary spring 44 drives the positioning block 38 to reset and move, and then resets and moves it on the positioning square column 37, thereby driving the positioning tooth block 42 to reset and move it toward the direction of the driving gear 10, so that the driving gear 10 is meshed with the positioning tooth block 42, thereby limiting the driving gear 10 to prevent the driving gear 10 from rotating due to non-human factors when the device is in use, thereby further improving the locking actuator. The installation effect of the parts on the steel mesh is improved to prevent the steel mesh from being dislocated during use; at the same time, the strength of the auxiliary spring 44 causes pressure to act on the positioning cross plate 39. Since the positioning tooth block 42 has been limited and cannot move, the positioning cross plate 39 moves within the upper limit of the positioning cylinder 40, so that the auxiliary spring 44 is in a buffering state, thereby strengthening the connection strength of the positioning tooth block 42 to the driving gear 10, and further improving the limiting effect of the driving gear 10; at the same time, when the driving gear 10 is limited, the positioning spring 15 in the buffering state cannot be reset, and the elastic force caused by the inability to reset acts on the driving gear 10 through the positioning rack 14. Since the driving gear 10 cannot rotate, the meshing strength between the driving gear 10 and the positioning tooth block 42 is strengthened, so that the positioning tooth block 42 cannot move due to non-human factors, thereby improving the use effect of the device and reducing the limitations of the device during use;

[0047] When the positioning block 38 is reset, that is, when it moves toward the direction of the driving gear 10, the inclined surface of the self-locking bevel block 47 on the positioning block 38 contacts the inclined surface of the self-locking bevel groove 48, and under the action of pressure, the self-locking bevel block 47 moves within the storage groove 46 to limit the self-locking spring 50 in a buffer state until the self-locking bevel block 47 is no longer located in the self-locking bevel groove 48, thereby releasing the limit setting of the positioning block 38, so that the positioning block 38 can move toward the direction of the driving gear 10, and when encountering the next self-locking bevel groove 48, the self-locking spring 50 resets and automatically limits the positioning block 38; when the positioning block 38 wants to move away from the driving gear 10, the right-angled surface on the self-locking bevel groove 48 It contacts the right-angled surface on the self-locking bevel block 47, thereby limiting the self-locking bevel block 47 in the self-locking bevel groove 48, thereby limiting the positioning block 38 so that the positioning block 38 cannot move. Only by manually pulling the self-locking bevel block 47 outward so that it is no longer located in the self-locking bevel groove 48 can the positioning tooth block 42 move away from the driving gear 10, so that the positioning block 38 can only move in one direction, and the moving direction is also limited to moving only toward the driving gear 10, thereby avoiding the movement of the positioning tooth block 42 due to non-human factors during use, so that the positioning tooth block 42 is no longer connected to the driving gear 10, thereby improving the safety of the device during use, avoiding the locking actuator assembly from being dislocated due to non-human factors when installing the steel mesh, and improving the use effect of the device.

[0048] The equidistant frame 31 of the present embodiment is also provided with a re-scraping cleaning assembly; the re-scraping cleaning assembly comprises a re-movable base plate 52 arranged on one side of the top of the equidistant frame 31, a re-movable square column 53 is penetrated and slidably connected to the re-movable base plate 52, one end of the re-movable square column 53 is connected to a re-movable limit plate 54, and the other end is connected to a re-movable square plate 55, a scraping block 56 is installed on the re-movable square plate 55, and the scraping block 56 is in contact with the steel mesh; suction devices 57 are also installed on both sides of the scraping block 56, and the output end of the suction device 57 faces the steel mesh; a re-movable spring 58 is sleeved on the re-movable square column 53, and one end of the re-movable spring 58 is connected to the re-movable base plate 5 2, and the other end is connected to the compound limit plate 54; an active contact block 59 is installed on the compound limit plate 54; a rotating disc 60 is also rotatably installed on the fixed pulley 23, and a rotating cylinder 61 is also installed on the side of the rotating disc 60 away from the fixed pulley 23, and a rotating horizontal block 62 is slidably connected to the rotating cylinder 61, and two limiting cylinders 63 are symmetrically installed on one side of the rotating horizontal block 62, and the two limiting cylinders 63 are slidably connected to a limiting base plate 64, and the limiting base plate 64 is arranged on the T-shaped clamping plate 6; a driven contact block 65 is installed on the other side of the rotating horizontal block 62, and the active contact block 59 is located on the moving path of the driven contact block 65;

[0049] When the locking actuator assembly is installed on the steel mesh, it is placed in the rectangular frame 5, so that the rotation of the fixed pulley 23 drives the rotating disc 60 to rotate, so that the rotating cylinder 61 on it moves back and forth in the rotating cross block 62, so that it moves back and forth on the limiting substrate 64 through the limiting cylinder 63, thereby driving the driven contact block 65 to move back and forth, so that it constantly contacts the active contact block 59, so that when it is subjected to force, it moves on the limiting position of the compound substrate 52 through the compound square column 53, so that the compound spring 58 is in a buffering state, thereby driving the scraper block 56 to move, so that it moves on the surface of the steel mesh; when the active contact block 59 is no longer subjected to force, the scraper block 56 is reset and moved by the reset of the compound spring 58, so that it moves back and forth on the surface of the steel mesh, so that the impurities adsorbed and adhered on the surface of the steel mesh can be cleaned during the installation process, so as to avoid the presence of these impurities affecting the printing effect of the solder paste, so that the solder paste passes through the steel mesh The pads printed on the PCB board are unqualified, thereby avoiding the presence of these impurities affecting the effect of components installed on the pads during the reflow soldering process, thereby improving the reflow soldering effect of the device on SMT; at the same time, when the steel mesh is removed, the fixed pulley 23 will be reset and rotated, and the rotating cross block 62 will also move back and forth, so that the driven contact block 65 continues to contact the active contact block 59, so that the scraper block 56 still moves back and forth on its surface during the removal of the steel mesh, thereby cleaning the solder paste adhered to the steel mesh during printing, avoiding the need for manual cleaning by the staff, reducing the intensity of the staff, and improving the use effect of the device; at the same time, by using the suction device 57, the suction force generated acts on the holes on the steel mesh, which can clean the residual solder paste in the holes of the steel mesh, improve the cleaning effect of the steel mesh, and further reduce the limitations of the device during use.

[0050] The present invention also provides a reflow soldering method for SMT, comprising the following steps:

[0051] S001, placing the steel mesh required for printing during reflow soldering in the rectangular frame 5, and completing the installation of the steel mesh by locking the actuator assembly;

[0052] S002, print solder paste on the pads of the PCB board through the steel mesh, and place the components to be soldered in the area to make an SMT board;

[0053] S003, placing the SMT board on the conveyor belt of the reflow oven 1, and the different temperature zones inside can complete the reflow operation of the SMT board, so as to fix the components on the PCB board.

[0054] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0055] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A reflow soldering device for SMT, comprising a reflow soldering furnace (1) and a steel mesh; a telescopic cylinder (2) is provided on the side of the reflow soldering furnace (1); a U-shaped base plate (3) is installed on the output end of the telescopic cylinder (2); a guide rail is provided on the opposite surface of the U-shaped base plate (3); a printing device (4) is slidably provided on the guide rail; the characteristics are: The U-shaped substrate (3) is also provided with a locking actuator component, which is used for the installation / removal of the steel mesh; the locking actuator component comprises a rectangular frame (5), and the steel mesh is located in the rectangular frame (5); a T-shaped clamp (6) is installed on the outer wall of the rectangular frame (5), and a wire take-up roller (7) is installed at the interlayer of the T-shaped clamp (6), and an energy dissipation and anti-movement mechanism is provided on the wire take-up roller (7), so that the energy dissipation and anti-movement mechanism can prevent the steel mesh from soldering to the pads on the PCB board. The paste printing process generates shaking; a telescopic square column (8) is installed on all four sides of the top of the rectangular frame (5), and the plurality of telescopic square columns (8) are connected to the U-shaped base plate (3); a retaining T-plate (9) is installed on the outer wall of the rectangular frame (5) away from the T-shaped clamping plate (6), and a driving gear (10) is rotatably connected to the retaining T-plate (9); the retaining T-plate (9) is also provided with an engaging and fixing unit, which is used to limit the driving gear (10); A first base plate (11) is installed on the top and bottom of the fixed T-plate (9); a movable sliding column (12) is slidably connected to each of the two first base plates (11); a movable square plate (13) is installed at both ends of the two movable sliding columns (12); the two movable square plates (13) on one movable sliding column (12) are commonly connected to a movable rack (14); the two movable racks (14) are meshingly connected to the driving gear (10); a movable spring (15) is sleeved on the movable sliding column (12); one end of the movable spring (15) is connected to the movable square plate (13), and the other end is connected to the first base plate (11); One end of a bent square rod (16) is mounted on a movable square plate (13) on the two movable racks (14); the other end of the bent square rod (16) is located in the rectangular frame (5) and is mounted with a movable transverse plate (17); the two movable transverse plates (17) are symmetrically arranged; two symmetrically arranged locking slide posts (18) are penetrated through the opposite surfaces of the two movable transverse plates (17); the locking slide posts (18) are slidably matched with the movable transverse plates (17); the locking slide posts (18) are close to the rectangular frame (5); A movable limit plate is provided at one end of the inner wall; two locking slide posts (18) on the movable transverse plate (17) are connected to a locking long block (19) at one end away from the movable limit plate, and rubber pads (20) are provided on the opposite surfaces of the two locking long blocks (19), and the side surface of the steel mesh is located on the moving path of the rubber pads (20); a locking spring (21) is sleeved on the locking slide post (18), one end of the locking spring (21) is connected to the locking long block (19), and the other end is connected to the movable transverse plate (17).

2. A reflow soldering device for SMT according to claim 1, characterized in that: The energy dissipation and anti-movement mechanism comprises a retaining square seat (22) arranged on the bent square rod (16); a fixed pulley (23) is installed on the side of the T-shaped clamp (6) away from the wire-receiving roller (7), and the fixed pulley (23) is located at the interlayer of the T-shaped clamp (6); the fixed pulley (23) and the wire-receiving roller (7) are symmetrically arranged, and the retaining square seat (22) is located between the fixed pulley (23) and the wire-receiving roller (7); one end of a cable (24) is installed on the retaining square seat (22), and the other end of the cable (24) bypasses the fixed pulley (23) and is wound around the wire-receiving roller (7) to be connected; The top and bottom of the take-up roller (7) are both mounted with displacement screws (25), the two displacement screws (25) being symmetrically arranged and having opposite threads; a spring spring (26) is mounted on the displacement screw (25), and the end point of the spring spring (26) is connected to the T-shaped clamp (6); a displacement block (27) is threadedly connected to the two displacement screws (25), a guide square plate (28) is mounted on the side of the displacement block (27), a guide cylinder (29) is slidably connected to the guide square plate (28), and the guide cylinder (29) is arranged on the T-shaped clamp (6).

3. A reflow soldering device for SMT according to claim 2, characterized in that: A Z-shaped square plate (30) is further installed on the side of the displacement block (27) away from the guide square plate (28), and an equidistant frame (31) is installed on the Z-shaped square plate (30), and the two equidistant frames (31) are respectively located at the top and bottom of the steel mesh; guide slide bars (32) are arranged on all sides of the top of the equidistant frame (31), and the guide slide bars (32) and the equidistant frames (31) are slidably matched; the end of the guide slide bar (32) away from the steel mesh is connected to a guide limit plate (33); a guide spring (34) is sleeved on the guide slide bar (32), one end of the guide spring (34) is connected to the guide limit plate (33), and the other end is connected to the equidistant frame (31); a buffer round pad (35) is installed on the end of the guide slide bar (32) close to the steel mesh.

4. The reflow soldering device for SMT according to claim 1, characterized in that: The engaging and rotating unit comprises two second base plates (36) symmetrically arranged on the side of the retaining T-plate (9) away from the T-shaped clamping plate (6), and positioning square columns (37) are installed on the opposite surfaces of the two second base plates (36). A positioning square block (38) is slidably connected to the positioning square column (37), and a positioning horizontal plate (39) is provided on the side of the positioning block (38) away from the T-shaped clamping plate (6). A positioning cylinder (40) is slidably connected to the positioning horizontal plate (39), and one end of the positioning cylinder (40) is connected to a positioning limit plate (41), and the other end is connected to a positioning tooth block (42). ), the driving gear (10) is located on the moving path of the positioning gear block (42) and the two are meshed; the positioning cylinder (40) is sleeved with a positioning spring (43), one end of the positioning spring (43) is connected to the positioning limit plate (41), and the other end is connected to the positioning horizontal plate (39); the positioning square column (37) is sleeved with an auxiliary spring (44), one end of the auxiliary spring (44) is connected to the positioning block (38), and the other end is connected to the auxiliary limit plate (45), and the auxiliary limit plate (45) is arranged at one end of the positioning square column (37) away from the second substrate (36).

5. The reflow soldering device for SMT according to claim 4, characterized in that: The opposite surfaces of the interior of the positioning block (38) are provided with storage square grooves (46), and a self-locking inclined block (47) is slidably provided in the storage square grooves (46); the top and bottom of the positioning square column (37) are provided with a plurality of self-locking inclined grooves (48), and a part of the self-locking inclined block (47) is located in the self-locking inclined grooves (48). When the positioning block (38) moves with the self-locking inclined block (47) toward the driving gear (10), the inclined surface on the self-locking inclined block (47) and the self-locking inclined groove (48) are aligned. The inclined surface on the self-locking block (47) fits in with each other; a self-locking cylinder (49) is installed on the side of the self-locking inclined block (47) away from the self-locking inclined groove (48), and the self-locking cylinder (49) passes through the positioning block (38) and the two are slidably connected; a self-locking spring (50) is sleeved on the self-locking cylinder (49), one end of the self-locking spring (50) is connected to the positioning block (38), and the other end is connected to a self-locking limit plate (51), and the self-locking limit plate (51) is arranged on the end of the self-locking cylinder (49) away from the positioning block (38).

6. The reflow soldering device for SMT according to claim 3, characterized in that: The equidistant frame (31) is also provided with a re-scraping cleaning assembly; the re-scraping cleaning assembly comprises a re-movable base plate (52) provided on one side of the top of the equidistant frame (31); a re-movable square column (53) passes through and is slidably connected to the re-movable base plate (52); one end of the re-movable square column (53) is connected to a re-movable limit plate (54) and the other end is connected to a re-movable square plate (55); a scraping block (56) is mounted on the re-movable square plate (55); the scraping block (56) is in contact with the steel mesh; suction devices (57) are also mounted on both sides of the scraping block (56); the output end of the suction device (57) faces the steel mesh; a re-movable spring (58) is sleeved on the re-movable square column (53); one end of the re-movable spring (58) is connected to the re-movable base plate (52) and the other end is connected to the re-movable limit plate (54); an active contact block (59) is mounted on the re-movable limit plate (54).

7. A reflow soldering device for SMT according to claim 6, characterized in that: A rotating disc (60) is rotatably mounted on the fixed pulley (23), a rotating cylinder (61) is mounted on the side of the rotating disc (60) away from the fixed pulley (23), a rotating cross block (62) is slidably connected to the rotating cylinder (61), two limiting cylinders (63) are symmetrically mounted on one side of the rotating cross block (62), the two limiting cylinders (63) are slidably connected to a limiting base plate (64), and the limiting base plate (64) is arranged on the T-shaped clamping plate (6); a driven contact block (65) is mounted on the other side of the rotating cross block (62), and the active contact block (59) is located on the moving path of the driven contact block (65).

8. A reflow soldering method for SMT, using the reflow soldering device for SMT as claimed in claim 1, characterized in that: Includes steps: S001. Place the steel mesh required for printing during reflow soldering in the rectangular frame (5), and complete the installation of the steel mesh by locking the actuator assembly; S002. Print solder paste on the pads of the PCB board through a steel mesh, and place the components to be soldered on the pads to make an SMT board; S003. The SMT board is placed on a conveyor belt in a reflow oven (1). Different temperature zones inside the oven are used to complete the reflow operation on the SMT board, thereby fixing the components on the PCB.

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