High-efficiency and Precision Temperature-controlled Reflow Soldering Equipment

Abstract

The present invention provides an efficient and precise temperature-controlled reflow soldering device, which includes a step-by-step heating device, a cooling device and a recovery device connected in sequence; the step-by-step heating device includes a plurality of heating modules, and a partition cavity is arranged between two adjacent heating modules; a partition return channel is arranged at the conveying port of the heating cavity and the partition cavity; an air suction channel is arranged between two adjacent cooling modules in the cooling device; a cooling cavity is arranged on one side of each cooling module in the vertical direction, and a cooling air supply fan and a cooling air suction fan are arranged on the other side. The partition return channel can form an air flow flowing into the heat source cavity along the vertical direction at the conveying port, thereby forming an air wall to block the longitudinal flow of air at the conveying port, reducing the air flow and heat interference at the conveying port, and improving the heating efficiency; through the cooperation of the cooling air supply fan and the cooling air suction fan, the air flow at the circuit board can be accelerated, and the cooling efficiency can be improved; both the heating and cooling efficiencies are improved, thereby ensuring the solder joint quality and improving the production efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit board soldering, and particularly to an efficient and precision temperature-controlled reflow soldering device. Background Art

[0002] Reflow soldering is a process of heating a circuit board with solder, melting the solder and making it flow and infiltrate again, and finally cooling the circuit board to solidify the solder, thus completing the soldering process of the circuit board.

[0003] During the heating process, the circuit board usually needs to pass through multiple heating modules in sequence, and the heating temperatures of the multiple heating modules gradually increase, so as to gradually raise the circuit board to the soldering temperature. Since the circuit board needs to enter and exit the heating module, a conveying port is provided in the heating module. At the conveying port, the heat between adjacent heating modules will interfere with each other, resulting in temperature differences at different positions within the same heating module, making the circuit board unevenly heated within the same heating module and not easily raised to the preset temperature, affecting the solder joint quality and production efficiency.

[0004] During the cooling process, rapid cooling is required to avoid the solder flowing again and affecting the solder joint quality. The existing cooling devices have low cooling and heat dissipation efficiency and need to be further improved. Summary of the Invention

[0005] The present invention provides an efficient and precision temperature-controlled reflow soldering device, which can improve the heating and cooling efficiency, thereby ensuring the solder joint quality and improving the production efficiency.

[0006] The present invention provides an efficient and precision temperature-controlled reflow soldering device, including a step-by-step heating device, a cooling device and a recovery device connected in sequence;

[0007] The step-by-step heating device includes a plurality of heating modules, which are arranged at intervals longitudinally, and a partition cavity is provided between adjacent two heating modules; each heating module is provided with a heat source cavity and a heating cavity, the heat source cavity is used to provide heat energy and convey it to the heating cavity; a conveying port is formed between the heating cavity and the partition cavity, and the conveying port is used for the circuit board to pass through; a partition reflux channel is provided at the conveying port, the partition reflux channel is in the shape of a slit extending horizontally, one end of the partition reflux channel in the vertical direction is located at the conveying port, and the other end communicates with the heat source cavity, so as to form an air flow flowing vertically into the heat source cavity at the conveying port;

[0008] The cooling device comprises a cooling module, wherein there are more than two cooling modules and the cooling modules are arranged at intervals in the longitudinal direction; an air suction channel is provided between two adjacent cooling modules; each cooling module is provided with a cooling chamber on one side in the vertical direction, and a cooling air supply fan and a cooling air suction fan are provided on the other side, the air supply port of the cooling air supply fan is connected to the cooling chamber, and the air suction port of the cooling air suction fan is connected to the cooling chamber through the air suction channel to suck away the hot air in the cooling chamber; the air outlet of the cooling air suction fan is connected to the recovery device;

[0009] The recovery device is used for recovering soldering flux.

[0010] Wherein, the heating module comprises a heater, and the heater comprises a housing, a heat-saturating component, a heating component and a heating fan;

[0011] The heat-saturating assembly is fixed to the outer shell, and includes an inner shell, an air outlet plate and a heat-saturating plate; the inner shell and the outer shell are both in the shape of a cube with one side open, and the opening directions of the two are the same; the inner shell is fixed in the outer shell, and the heat source cavity is formed between the two; the partition return channel is located between the openings of the inner shell and the outer shell; the air outlet plate is fixed at the opening of the inner shell, and a heat-saturating cavity is formed between the two; the heat-saturating plate is located in the heat-saturating cavity, the heat-saturating plate is parallel to the air outlet plate and is arranged at intervals, and a plurality of through holes are provided on the air outlet plate and the heat-saturating plate;

[0012] The heating component is disposed in the heat source cavity to provide heat energy;

[0013] The heating fan is fixed to the outer shell, the air inlet of the heating fan is located in the heat source cavity, and the air outlet is connected to the heat-averaging cavity through a hot air duct, the hot air duct has an air outlet end facing the heat-averaging plate, the air outlet end is located on the side of the heat-averaging plate away from the air outlet plate, and the air outlet end is spaced apart from the heat-averaging plate.

[0014] Wherein, the heaters are arranged in pairs, a pair of the heaters are arranged vertically and symmetrically, and the space between the pair of the heaters forms a heating chamber.

[0015] Among them, the partition return channel is divided into a first sub-channel and a second sub-channel in the longitudinal direction; the first sub-channel and the second sub-channel are both slit-shaped; the first sub-channel is closer to the heating chamber than the second sub-channel; in the longitudinal direction, the size of the second sub-channel is smaller than that of the first sub-channel.

[0016] Wherein, the cooling module comprises a cooling frame, and the cooling air supply fan and the cooling air suction fan are both fixed to the cooling frame;

[0017] The cooling frame is shell-shaped, and an air suction cavity is formed therein; an air inlet hole is provided on the side wall of the cooling frame, and the air inlet hole communicates the air suction cavity with the air suction channel. The air suction port of the cooling air suction fan is communicated with the air suction cavity, so that the air flow in the cooling cavity enters the air suction cavity through the air suction channel and the air inlet hole and is discharged.

[0018] Wherein, the cooling module further includes an air distribution component; the air distribution component is fixed on the cooling frame; the air distribution component includes an air distribution shell and an air distribution plate. The air distribution shell and the side wall of the cooling frame enclose an air distribution cavity; the air distribution shell includes a air supply plate, the air supply plate is arranged parallel to the air distribution plate, and a plurality of through holes are uniformly arranged on both of them; the air distribution plate is arranged in the air distribution cavity; the air supply port of the cooling air supply fan communicates with the air distribution cavity and faces the air distribution plate, so that the cooling air flow flows to the cooling cavity after passing through the air distribution plate and the air supply plate.

[0019] Wherein, the air suction port of one of the cooling air suction fans is communicated with all the partition cavities.

[0020] Wherein, the recovery device includes a recovery box body, a recovery filter screen and an exhaust pipe; a recovery inlet is provided on the side wall of the recovery box body, and the air outlet of the cooling air suction fan is communicated with the inside of the recovery box body through the recovery inlet; the exhaust pipe is fixed on the top of the recovery box body and communicated with the inside of the recovery box body for discharging the gas after recovery; the recovery filter screen is fixed inside the recovery box body, the recovery filter screen is arranged vertically and is located between the recovery inlet and the exhaust pipe.

[0021] Wherein, the recovery filter screen is inclined relative to the air flow direction at the recovery inlet.

[0022] Wherein, the recovery device further includes a recovery fan, the recovery fan is fixed on the recovery box body, the air inlet of the recovery fan is located outside the recovery box body and the air outlet is located inside the recovery box body. A guide plate is arranged between the air outlet of the recovery fan and the bottom of the exhaust pipe. The guide plate is located between the recovery fan and the recovery filter screen, and one end of the guide plate is connected to the recovery fan and the other end is connected to the bottom of the exhaust pipe to guide the air flow discharged from the recovery fan into the exhaust pipe.

[0023] The high-efficiency precision temperature-controlled reflow soldering equipment provided by the present invention can drive the air flow at the conveying port by the air flow flowing vertically into the heat source cavity along the partitioned reflux channel, so as to form an air flow flowing vertically into the heat source cavity at the conveying port, and further form an air wall, which can block the longitudinal air flow at the conveying port, reduce the air flow and heat interference between the heating cavity and the partitioned cavity at the conveying port, make the temperatures at various positions in the same heating cavity relatively consistent, ensure that the circuit board reaches the preset temperature in the heating cavity, improve the heating efficiency, and achieve high-efficiency precision temperature control; through the cooperation of the cooling air blower and the cooling air suction fan, the air flow at the circuit board can be accelerated, thereby improving the cooling efficiency; both the heating and cooling efficiencies are improved, thus ensuring the solder joint quality and improving the production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following briefly introduces the drawings required to be used in the embodiments. The drawings described below are only the corresponding drawings of some embodiments of the present invention.

[0025] Figure 1 is a schematic structural diagram of the high-efficiency precision temperature-controlled reflow soldering equipment provided by the preferred embodiment of the present invention

[0026] Figure 2 is Figure 1 a three-dimensional schematic diagram of the longitudinal section of the high-efficiency precision temperature-controlled reflow soldering equipment in

[0027] Figure 3 is Figure 1 a front projection diagram of the longitudinal section of the high-efficiency precision temperature-controlled reflow soldering equipment in

[0028] Figure 4 is Figure 1 a schematic structural frame diagram of the high-efficiency precision temperature-controlled reflow soldering equipment in

[0029] Figure 5 is Figure 4 a partial frame schematic diagram at the adjacent heating modules of the high-efficiency precision temperature-controlled reflow soldering equipment in

[0030] Figure 6 is Figure 2 a schematic structural diagram of the heater of the high-efficiency precision temperature-controlled reflow soldering equipment in

[0031] Figure 7 is Figure 6 an exploded schematic diagram of the heater in

[0032] Figure 8 is Figure 6 a three-dimensional schematic diagram of the transverse section of the heater in

[0033] Figure 9 is Figure 6Front projection view of the horizontal cross-section of the middle heater;

[0034] Figure 10 is Figure 6 Front projection view of the longitudinal cross-section of the middle heater;

[0035] Figure 11 is Figure 10 Enlarged view at position A in the middle;

[0036] Figure 12 is Figure 2 Schematic structural diagram of the cooling module of the high-efficiency precision temperature-controlled reflow soldering equipment in the middle;

[0037] Figure 13 is Figure 12 Schematic structural diagram of the cooling device of the cooling module in the middle;

[0038] Figure 14 is Figure 12 Exploded schematic diagram of the cooling device in the middle;

[0039] Figure 15 is Figure 12 Front projection view of the horizontal cross-section of the cooling device in the middle;

[0040] Figure 16 is Figure 2 Schematic structural diagram of the recycling device of the high-efficiency precision temperature-controlled reflow soldering equipment in the middle;

[0041] Figure 17 is Figure 16 Front projection view of the recycling device cut along the horizontal plane;

[0042] Figure 18 is Figure 16 Front projection view of the recycling device cut along the vertical plane in the middle. Detailed implementation manner

[0043] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0044] In the present invention, unless otherwise clearly specified and defined, terms such as "installation", "connection", "linkage", "fixation", etc. shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral body; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection through an intermediate medium, and it may be the internal communication of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0045] Please refer to Figure 1 , Figure 2 and Figure 3 , the high-efficiency precision temperature-controlled reflow soldering equipment provided by the preferred embodiment of the present invention includes a step-by-step heating device 100, a cooling device 200, and a recovery device 300 that are connected in sequence. The step-by-step heating device 100 is used to gradually heat and raise the temperature of the circuit board. The cooling device 200 is arranged at the end of the step-by-step heating device 100 and is used to cool the circuit board, thereby completing the reflow soldering operation. The cooling device 200 sucks away the hot air at the circuit board and sends it to the recovery device 300, and the recovery device 300 is used to recover the soldering flux in the air flow.

[0046] The high-efficiency precision temperature-controlled reflow soldering equipment further includes a base 801 and a top cover 802. The step-by-step heating device 100, the cooling device 200, and the recovery device 300 are all fixed on the base 801, and the top cover 802 covers the upper part of the step-by-step heating device 100, the cooling device 200, and the recovery device 300, which can make the step-by-step heating device 100, the cooling device 200, and the recovery device 300 in a relatively closed environment to avoid the overflow of gases such as soldering flux.

[0047] In this embodiment, the step-by-step heating device 100, the cooling device 200, and the recovery device 300 are arranged in sequence longitudinally and fixed on the base 801. A conveying device 400 is further arranged on the base 801, and the conveying device 400 is used to drive the circuit board to pass through the step-by-step heating device 100 and the cooling device 200 in sequence. The conveying device can adopt existing mature conveying devices, and the present invention will not describe the structure of the conveying device 400 in detail.

[0048] The step-by-step heating device 100 includes a plurality of heating modules, and the plurality of heating modules are arranged at intervals longitudinally in sequence. A partition cavity 109 is arranged between two adjacent heating modules. The circuit board can enter from the head end of the step-by-step heating module under the drive of the conveying device 400, pass through a plurality of heating modules in sequence, realize the gradual increase of temperature, and make the solder melt to weld and fix the electronic components to the circuit board; the circuit board is sent out from the end of the step-by-step heating device 100 and enters the cooling device 200.

[0049] In this embodiment, multiple heating modules are arranged longitudinally, and the heating temperature of the heating modules gradually increases in the direction approaching the cooling device 200, so as to gradually heat to a preset temperature through multiple stages. It can be understood that the horizontal X and the vertical Y in this embodiment are two mutually perpendicular directions on the horizontal plane and are both perpendicular to the vertical Z.

[0050] As Figure 4 and Figure 5 shown, each heating module is provided with a heat source cavity 102 and a heating cavity 103. The heat source cavity 102 is used to provide heat energy and transport it to the heating cavity 103. The heating cavity 103 is the area for heating the circuit board 901. A delivery port 108 is formed between the heating cavity 103 and the partition cavity 109. The delivery port 108 is used for the circuit board 901 to pass through, so that the circuit board 901 can move between the heating modules; the circuit board 901 can enter the heating cavity 103 from the delivery port 108, heat up in the heating cavity 103 and then move out of the heating cavity 103 from another delivery port 108, and move into the partition cavity 109, and enter another heating module through the delivery port 108 of another heating module.

[0051] As Figure 5 shown, a partition reflux channel 104 is provided at the delivery port 108. The partition reflux channel 104 is in the shape of a slit extending horizontally. One end of the partition reflux channel 104 in the vertical direction is located at the delivery port 108, and the other end communicates with the heat source cavity 102, so as to form an air flow flowing vertically into the heat source cavity 102 at the delivery port 108. The air flow flowing vertically into the heat source cavity 102 in the partition reflux channel 104 can drive the air flow at the delivery port 108, so as to form an air flow flowing vertically into the heat source cavity at the delivery port 108, and further form an air wall, which can block the air flow in the longitudinal direction at the delivery port 108, reduce the air flow and heat interference between the heating cavity 103 and the partition cavity 109 at the delivery port 108, the temperature at each position in the same heating cavity 103 is relatively consistent, and ensure that the circuit board 901 reaches the preset temperature in the heating cavity 103, realizing efficient and precise temperature control, improving the heating efficiency and ensuring the solder joint quality. At the same time, the partition reflux channel 104 can bring the hot air in the heating cavity 103 back to the heat source cavity 102, so that the heat source cavity 102, the heating cavity 103 and the reflux channel can be connected into an internal circulation air flow, so that the heat energy can be recycled, saving energy consumption and reducing costs.

[0052] In this embodiment, the heating module includes a heater 10, and a heat source cavity 102 is disposed within the heater 10. The heaters 10 can be arranged in pairs. A pair of heaters 10 are arranged vertically and symmetrically, and the space between the pair of heaters 10 forms a heating cavity 103. Further, there are two pairs of heaters 10 in each heating module, that is, the heating module includes four heaters 10. The two pairs of heaters 10 are arranged longitudinally. Using multiple heaters 10 can effectively improve the heating efficiency and ensure the uniformity of heating. The structures of the four heaters 10 are similar. Taking the structure of one of the heaters 10 as an example for specific description. Here, in other embodiments, there can also be only one pair of heaters 10 in each heating module, and the two heaters 10 are arranged vertically; that is, the foregoing each heating module can be divided into two heating modules; or there are two independent heaters 10, and the two heaters 10 are arranged longitudinally. A cover plate is covered at the air outlet surface of the heaters 10 to form a relatively enclosed heating cavity 103; or, there can also be only one heater 10, that is, the heating module only has one heat source cavity 102 and one heating cavity 103.

[0053] As Figure 5 , Figure 6 , Figure 7 shown, the heater 10 includes a housing 11, a heat equalizing component 12, a heating component 13, and a heating fan 14. The housing 11 is used to provide support for the entire heater 10, and the housing 11 can be fixedly connected to the base of the high-efficiency precision temperature-controlled reflow soldering equipment. The heat equalizing component 12 is fixed within the housing 11 and is used to make the heat flow more evenly to the circuit board; the heating component 13 is disposed in the housing 11 and is used to provide heat energy; the heating fan 14 is fixed to the housing and is used to drive the air flow within the housing 11 so that the heat energy generated by the heating component 13 can flow to one side of the heater 10 through the heat equalizing component 12, thereby forming a circulating heating to make full use of the heat energy.

[0054] The heat equalizing component 12 includes an inner housing 121, an air outlet plate 122, and a heat equalizing plate 123. The housing 11 and the inner housing 121 are in the shape of a cube with one side open, and their opening directions are the same. The inner housing 121 is fixed within the housing 11, and a heat source cavity 102 is formed between them. The heating component 13 is disposed in the heat source cavity 102 and is used to provide heat energy. A partition reflux channel is located between the openings of the inner housing 121 and the housing 11. The opening of the inner housing 121 is for the heat to flow out. The air on one side of the heater 10 can enter the heat source cavity 102 through the gap between the openings of the inner housing 121 and the housing 11, so as to be heated again by the heating component 13 and flow to one side of the heater 10 through the heat equalizing component 12, thereby forming a circulating heating to make full use of the heat energy.

[0055] The air outlet plate 122 is fixed to the opening of the inner shell 121, and a heat-averaging chamber 105 is formed between the two, so that the heat entering the inner shell 121 needs to flow out through the air outlet plate 122. The heat-averaging plate 123 is located in the heat-averaging chamber 105, and the heat-averaging plate 123 and the air outlet plate 122 are arranged parallel and spaced apart, and both are provided with a plurality of through holes; the air outlet of the heating fan 14 is connected to the inner shell 121, and its air outlet direction is toward the heat-averaging plate 123.

[0056] The heating fan 14 is used to provide power for gas flow, and its air inlet 141 is located in the heat source cavity 102, and the air outlet is connected to the heat-equalizing cavity 105 through the hot air duct 142. The heating fan 14 can absorb the heat in the heat source cavity 102, and at the same time make the air at the circuit board flow back to the heat source cavity 102; after the heating fan 14 inhales the hot air, it flows to the circuit board through the hot air duct 142 and the heat-equalizing component 12, and the heat-equalizing component 12 can make the hot air flow evenly to the circuit board, so that all parts of the circuit board are heated evenly. The heating component 13 is located between the air inlet 141 of the heating fan 14 and the inner shell 121, so that the heating component 13 is located between the air inlet 141 and the return channel, so that the airflow needs to be heated by the heating component 13 before entering the air inlet 141.

[0057] The hot air duct 142 has an air outlet end 143 facing the vapor chamber 123 . The air outlet end 143 is located on a side of the vapor chamber 123 away from the air outlet plate 122 . The air outlet end 143 is spaced apart from the vapor chamber 123 so that the hot air flow can overflow from the edge of the vapor chamber 123 . The hot air flow sucked by the heating fan 14 flows to the heat spreader 123 through the hot air duct 142, part of the hot air passes through the through holes of the heat spreader 123 and flows to the air outlet plate 122, and the other part flows to the air outlet plate 122 from the edges of the heat spreader 123. The hot air flow can be dispersed by the heat spreader 123 with multiple through holes, so that the hot air flow is dispersed and then flows to the air outlet plate 122, so that the wind pressure at each position of the air outlet plate 122 is roughly the same; the dispersed hot air flow flows to the circuit board through the multiple through holes of the air outlet plate 122, and the multiple through holes evenly distributed on the air outlet plate 122 can make the hot air flow evenly flow from the air outlet plate 122 to the circuit board, and an equal-pressure uniform air heating structure is formed on the air outlet surface of the air outlet plate 122, so that the heated hot air can be evenly blown out on the entire board surface of the air outlet plate 122, so that the circuit board is evenly heated, the temperature difference is reduced, and the quality of the solder joints is improved. The air outlet height of the air outlet plate 122 is about 20 mm-30 mm, so that uniform hot air can just blow to the circuit board, which can achieve the heating effect on the circuit board while avoiding blowing off the circuit board components.

[0058] The plurality of through holes on the air outlet plate 122 and the heat spreader 123 are arranged in a diamond shape in a uniform manner, such that three adjacent through holes are arranged to form an equilateral triangle, and the distance between each through hole and its adjacent through holes is the same, thereby achieving the effect of uniform arrangement and further improving the air distribution effect. The hole density of the air outlet plate 122 is smaller than that of the heat spreader 123, which can make the hole density of the heat spreader 123 larger to facilitate the passage of hot air flow through the heat spreader 123; the smaller hole density of the air outlet plate 122 can make the air volume distribution of each through hole of the air outlet plate 122 relatively uniform, reducing the air volume difference caused by the distance from the heat spreader 123.

[0059] The through holes on the air outlet plate 122 are tapered holes, and the end with a larger aperture faces the inner shell 121. The hot air in the inner shell 121 flows from the thick end to the thin end of the tapered hole, and the velocity of the hot air flow will increase, enabling the heat to be quickly carried to the circuit board and improving the heating efficiency.

[0060] The hot air duct 142 is arranged vertically to form a vertically flowing hot air flow. The opening area of the air outlet end 143 is smaller than the area of the heat spreader 123. In the horizontal projection of the heat spreader 123 and the air outlet end 143, the four peripheral edges of the heat spreader 123 protrude beyond the air outlet end 143, so that the hot air flow flowing out from the air outlet end 143 all needs to pass through the heat spreader 123 to improve the air distribution effect.

[0061] As Figure 2 shown, the heat spreader 123 is square, and its four sides are parallel to the four sides of the opening of the inner shell 121 for easy corresponding cooperation. The air outlet end 143 of the hot air duct 142 is square, and the heat spreader 123 and the air outlet end 143 are arranged at an angle of 45°, so that each corner of the heat spreader 123 protrudes beyond the respective edges of the air outlet.

[0062] Each heat spreader 123 is fixed to the inner shell 121 by two columns 124. The two columns 124 are located outside the hot air duct 142. By using the columns 124, the heat spreader 123 can be fixed in the inner shell 121, and a certain interval is maintained between the heat spreader 123 and the air outlet end 143 of the hot air duct 142.

[0063] In this embodiment, the inner shell 121 is in the shape of a cuboid, and its opening is rectangular. The air outlet plate 122 is correspondingly a rectangular plate. The length directions of both are horizontal; there are two heat spreaders 123 arranged along the length direction of the air outlet plate 122, and correspondingly there are two hot air ducts 142 respectively arranged corresponding to the two heat spreaders 123; the two hot air ducts 142 are arranged along the length direction of the air outlet plate 122 and symmetrically arranged on both sides of the heating fan 14. By using the cooperation of the two heat spreaders 123 and the two hot air ducts 142, the air outlet of the rectangular air outlet plate 122 can be made uniform in the horizontal direction.

[0064] The partition return channel 104 is longitudinally divided into a first sub-channel 1041 and a second sub-channel 1042. Both the first sub-channel 1041 and the second sub-channel 1042 are slit-shaped. The first sub-channel 1041 is closer to the heating chamber 103 than the second sub-channel 1042. The width of the first sub-channel 1041 is greater than the width of the second sub-channel 1042. It can be understood that the width here refers to the dimension of the sub-channel in the longitudinal direction. In the longitudinal direction, the dimension of the second sub-channel 1042 is smaller than that of the first sub-channel 1041.

[0065] The width of the first sub-channel 1041 is greater than the width of the second sub-channel 1042, so that the second sub-channel 1042 forms a relatively narrower slit compared to the first sub-channel 1041, and the air flow velocity therein is relatively larger than that in the first sub-channel 1041. As a result, two air flows can be formed at the delivery port 108 of the heating chamber 103, improving the stability of the air wall at the delivery port 108 and preventing the air in the partition chamber 109 from entering the heating chamber 103, thereby avoiding the mutual interference of heat between different heating modules. Since the greater the air flow velocity, the relatively smaller the air pressure at that position, the air pressure near the partition chamber 109 is smaller than the air pressure near the heating chamber 103, thus preventing the air in the partition chamber 109 from directly entering the heating chamber 103 and avoiding the temperature in the heating chamber 103 from being interfered by the temperature in the partition chamber 109.

[0066] There is a gap between the peripheral side walls of the outer shell 11 and the peripheral side walls of the inner shell 121, forming a return channel that connects the heating chamber 103 and the heat source chamber 102. The return channel includes a partition return channel 104 and an inner return channel 106. The partition return channel 104 is located between the long sides of the outer shell 11 and the inner shell 121, so that the partition return channel is in the shape of a slit arranged transversely. The inner return channel 106 is located between the short sides of the outer shell 11 and the inner shell 121. There are two partition return channels 104 and two inner return channels 106. In the longitudinal direction, the inner shell 121 is located between the two partition return channels 104. In the transverse direction, the inner shell 121 is located between the two inner return channels 106. In this embodiment, a part of the side wall of the outer shell 11 in the transverse direction is formed by a part of the support plate provided by reflow soldering, so it is not shown in the figure.

[0067] At the entrance of the partition return channel 104, a partition return plate 162 and a partition plate 163 are provided. The partition return plate 162 and the partition plate 163 are connected to form an L shape. The side of the partition return plate 162 away from the partition plate 163 is fixedly connected to the inner shell 121. A plurality of return holes 1620 are provided on the partition return plate 162, and the plurality of return holes 1620 are arranged horizontally. The partition plate 163 is located between the inner shell 121 and the outer shell 11. The partition plate 163 divides the return channel longitudinally into a first sub-channel 1041 and a second sub-channel 1042. The first sub-channel 1041 is located between the side wall of the inner shell 121 and the partition plate 163 and communicates with the return holes 1620; the second sub-channel 1042 is located between the side wall of the outer shell 11 and the partition plate 163. Through the partition plate 163, the partition return channel 104 can be divided into a first sub-channel 1041 and a second sub-channel 1042. The width of the first sub-channel 1041 is greater than the width of the second sub-channel 1042, that is, the distance between the partition plate 163 and the outer shell 11 is less than the distance between the partition plate 163 and the side wall of the inner shell 121.

[0068] In this embodiment, through the setting of the partition return channel 104, the partition cavity can play a better partition role, and the temperature between two adjacent heating cavities can be guaranteed to be between 40 degrees and 60 degrees. Through the setting of the first sub-channel and the second sub-channel, the temperature difference can exceed 60 degrees, ensuring that the circuit board can be heated step by step in stages.

[0069] In this embodiment, the air outlet plate 122, the partition return plate 162 and the partition plate 163 are integrally formed and formed by bending a plate, which is convenient for processing and preparation.

[0070] At the entrance of the inner return channel 106, an inner return plate 161 is provided. A plurality of strip holes 1610 are provided on the inner return plate 161, and the plurality of strip holes 1610 are arranged longitudinally. The length direction of the plurality of strip holes 1610 is horizontal. The strip holes 1610 can be used to allow the air in the heating cavity 103 to enter the inner return channel, and the flow rate at the strip holes 1610 is greater than the flow rate in the partition return channel 104, improving the return efficiency. In this embodiment, the inner return plate 161 is fixed to the air outlet plate 122. Of course, in other embodiments, the inner return plate 161 can also be directly fixed to the inner shell 121.

[0071] In the same heating module, a support member is provided between two adjacent heaters 10 at the bottom. The support member is fixedly connected to the two outer shells 11. The support member has two support plates. The tops of the two support plates protrude from the partition reflux plate 162 and are supported below the guide rod. The guide rod is used for guiding the circuit board 901 conveying device. The support plates can facilitate the support of the guide rod. The support plates and the side walls of the outer shell 11 are in the same vertical plane. The support plates can act as a partition wall, enabling the air in the heating chamber 103 to enter the heat source chamber 102.

[0072] Between two adjacent heating modules, the open ends of the side walls of the two adjacent outer shells 11 are both relatively close to the closed end of the outer shell 11 with respect to the partition reflux plate 162, that is, the inlet of the second sub-channel 1042 is relatively closer to the heat source chamber 102 than the inlet of the first sub-channel 1041. Thus, the air in the partition chamber 109 can also enter the heat source chamber 102, forming a negative pressure in the partition chamber 109, and further preventing the hot air in the heating chamber from entering the partition chamber and avoiding mutual interference with other adjacent heating chambers.

[0073] The cooling device 200 is arranged at the end of the step-by-step heating device 100. The cooling device 200 includes cooling modules 20. There are two or more cooling modules 20, which are arranged at intervals longitudinally. Using two or more cooling modules 20 can improve the cooling efficiency. In this embodiment, there are two cooling modules 20.

[0074] An air suction channel 201 is provided between two adjacent cooling modules 20. On one side in the vertical direction of each cooling module 20, there is a cooling chamber 202, and on the other side, there are a cooling air blower 23 and a cooling air suction fan 24. The air outlet of the cooling air blower 23 is communicated with the cooling chamber 202, and the air suction port of the cooling air suction fan 24 is communicated with the cooling chamber 202 through the air suction channel 201 to suck away the hot air in the cooling chamber 202. Through the cooperation of the cooling air blower 23 and the cooling air suction fan 24, the air flow at the circuit board 901 can be accelerated, thereby improving the cooling efficiency.

[0075] The cooling module 20 includes a cooling frame 21 and an air distribution component 22. The cooling frame 21 forms a cooling chamber 202 on one side in the vertical direction for the circuit board to pass through. The cooling air blower 23 and the cooling air suction fan 24 are both fixed on the other side of the cooling frame 21 in the vertical direction. In this embodiment, the lower side of the cooling frame 21 is for the circuit board to pass through, and the cooling air blower 23 and the cooling air suction fan 24 are both arranged on the upper side of the cooling frame 21.

[0076] The cooling frame 21 is in a shell shape, and an air suction chamber 211 is formed inside it. Air inlet holes 212 are provided on the side wall of the cooling frame 21. The air inlet holes 212 are communicated with the air suction chamber 211 and the air suction channel 201. The air at the circuit board can enter the air suction chamber 211 through the air suction channel 201 and the air inlet holes 212, and then be discharged.

[0077] There can be multiple air inlet holes 212, which are arranged in a matrix on the side wall of the cooling rack 21. This can reduce the impact on the structural strength of the side wall while ensuring the ventilation efficiency. The cooling rack 21 can be fixed on the bracket of the high-precision temperature-controlled reflow soldering equipment, and the cooling device can be suspended above the circuit board conveying channel, so that the cooling air flow can be output to the circuit board from top to bottom.

[0078] The air distribution component 22 is fixed to the cooling rack 21. The air distribution component 22 includes an air distribution housing 221 and an air distribution plate 222. The air distribution housing 221 and the side wall of the cooling rack 21 enclose an air distribution cavity 220. The air distribution housing 221 includes a air supply plate 2211. The air supply plate 2211 is arranged parallel to the air distribution plate 222, and a plurality of through holes are uniformly arranged on both of them. The air distribution plate 222 is arranged in the air distribution cavity 220 and is located between the air distribution cavity 220 and the air supply plate 2211. By using the air distribution component 22, the air can be evenly distributed to each position of the circuit board, so as to achieve the purpose of uniform cooling and heat dissipation, and then improve the cooling and heat dissipation efficiency.

[0079] The cooling air blower 23 and the cooling suction fan 24 are both fixed to the cooling rack 21 and are placed on both sides of the cooling rack 21 with the air distribution component 22. In this embodiment, the air distribution component 22 is located on the lower side of the cooling rack 21. The lower side of the air distribution component 22 is used for the circuit board to pass through. The air flow in the air distribution component 22 can flow downward to the circuit board to cool the circuit board. The cooling air blower 23 and the cooling suction fan 24 are both located on the upper side of the cooling rack 21, with a reasonable layout to avoid interfering with the air outlet of the air distribution component 22.

[0080] The air outlet of the cooling air blower 23 is communicated with the air distribution cavity 220 and faces the air distribution plate 222, so that the cooling air flow flows to the cooling cavity 202 after passing through the air distribution plate 222 and the air supply plate 2211. The cooling air blower 23 sucks in air from outside the cooling module 20 and generates a cooling air flow. After the cooling air flow enters the air distribution cavity 220, it flows to the air distribution plate 222. After being blocked by the air distribution plate 222 and filtered by the through holes, the cooling air flow is dispersed and then flows to the air supply plate 2211, and evenly flows to the circuit board through the through holes of the air supply plate 2211, so that each position of the circuit board is evenly affected by the air, and then uniform cooling and heat dissipation are achieved, the solder joint quality is ensured, and the cooling and heat dissipation efficiency is improved.

[0081] The air inlet of the cooling suction fan 24 is communicated with the air suction cavity 211, so that air flows into the air suction cavity 211 through the air inlet holes 212 and is discharged. The hot air at the circuit board enters the air suction cavity 211 through the air inlet holes 212, then enters the air inlet of the cooling suction fan 24, and is discharged outside the cooling module 20 through the cooling suction fan 24. The air inlet holes 212 are located on the side wall of the cooling frame 21, so as to reduce the mutual interference of the incoming air flow on the outgoing air flow of the air distribution component 22; through the cooperation of the cooling air supply fan 23 and the cooling suction fan 24, the air flow at the circuit board can be accelerated, thereby improving the cooling efficiency.

[0082] The impellers of both the cooling suction fan 24 and the cooling air supply fan 23 are arranged in the air suction cavity 211, and the drive motors of both the cooling suction fan 24 and the cooling air supply fan 23 are arranged outside the cooling frame 21, so as to facilitate the assembly connection of the cooling suction fan 24, the cooling air supply fan 23 and the cooling frame 21, facilitate the cooling suction fan 24 to suck the air in the air suction cavity 211, and at the same time make the impeller of the cooling air supply fan 23 relatively close to the air distribution component 22, which is beneficial to sending air flow into the air distribution component 22.

[0083] The cooling frame 21 is a cuboid, and one side of it is open. The air supply plate 2211 is located at the opening of the cooling frame 21. The air distribution shell 221 further includes a partition plate 2212 and two closed plates 2213. The partition plate 2212 is fixed to the cooling frame 21 to divide the space inside the cooling frame 21 into an air suction cavity 211 and an air distribution cavity 220. The partition plate 2212 can isolate the air suction cavity 211 and the air distribution cavity 220 to avoid the mutual interference of the two incoming and outgoing air flows. The partition plate 2212 is arranged opposite to the air supply plate 2211, and the two closed plates 2213 are arranged opposite to each other. The partition plate 2212, the air supply plate 2211 and the two closed plates 2213 enclose a cuboid-shaped air distribution shell 221. Both the cooling frame 21 and the air distribution shell 221 are cuboid-shaped, so as to facilitate the assembly connection between the two.

[0084] The two closed plates 2213 and the air supply plate 2211 are integrally formed, that is, formed by bending a plate, so as to facilitate processing and preparation and facilitate the assembly connection with the partition plate 2212.

[0085] The cooling frame 21 is a cuboid, the air supply plate 2211 is a rectangle, and the length directions of both are horizontal X. The cooling air supply fan 23 and the cooling suction fan 24 are arranged horizontally, so that the cooling air supply fan 23 and the cooling suction fan 24 are more evenly arranged on the cooling frame 21, making the force on the cooling frame 21 more balanced, and further ensuring the operation stability of the cooling air supply fan 23 and the cooling suction fan 24.

[0086] The hole density of the air supply plate 2211 is smaller than that of the air distribution plate 222, which can make the hole density of the air distribution plate 222 larger, facilitating the passage of hot air through the air distribution plate 222; the smaller hole density of the air supply plate 2211 can make the air volume distribution of each through-hole of the air supply plate 2211 relatively uniform, reducing the air volume difference caused by the distance from the air distribution plate 222.

[0087] The through-holes on the air supply plate 2211 are conical holes, and the end with a larger aperture faces the air distribution plate 222. The hot air in the air distribution cavity 220 flows from the thick end to the thin end of the conical hole, and the speed of the air flow will increase, enabling the cold air to be quickly brought to the circuit board and improving the cooling and heat dissipation efficiency.

[0088] The air outlet of the cooling air blower 23 is connected to the air distribution cavity 220 through an air supply duct 230; the air supply duct 230 is arranged vertically, the axis of the air supply duct 230 is perpendicular to the air distribution plate 222, and the two are spaced apart so that the air flow vertically flows towards the air distribution plate 222. The area of the air distribution plate 222 is larger than the cross-sectional area of the air supply duct 230. In the horizontal plane projection of the air distribution plate 222 and the air supply duct 230, the four peripheral edges of the air distribution plate 222 protrude from the edge of the air supply duct 230. So that the air flow flowing out of the air supply duct 230 all needs to pass through the air distribution plate 222 to improve the air distribution effect and further improve the cooling and heat dissipation efficiency.

[0089] In this embodiment, there are two or more cooling modules 20, which are arranged at intervals in the longitudinal direction in turn; an air suction channel is formed between the cooling frames 21 of two adjacent cooling modules 20. The air inlet holes 212 are arranged on the adjacent side walls between two adjacent cooling frames 21, and the air inlet holes 212 communicate with the air suction channel, and the air at the circuit board can be sucked away from the middle of the two cooling modules 20, thus avoiding the influence of heat on the two air supply positions.

[0090] A wind baffle 29 is fixed between the adjacent side walls of the two cooling frames 21. The wind baffle 29 is located on the side of the air suction hole away from the air distribution assembly 22. The wind baffle 29 can be used to prevent the air on the back of the cooling frame 21 (i.e., the upper side in the figure) from being inhaled, improving the air suction efficiency.

[0091] The air suction port of at least one of the cooling air suction fans 24 is connected to all the partition cavities 109. By using at least one cooling air suction fan 24, the air in the partition cavities 109 can be sucked away, thereby forming a negative pressure in the partition cavities 109. The air pressure in the partition cavities 109 is less than the air pressure in the heating cavity 103, thus preventing the air in the partition cavities 109 from directly entering the heating cavity 103 and interfering with the heating of the circuit board 901.

[0092] In this embodiment, the partition cavity 109 is connected to the air suction cavity of one of the cooling devices through a pipeline, so that the partition cavity is connected to the air suction port of the cooling air suction fan 24.

[0093] The air outlet of the cooling suction fan 24 is connected to the recovery device 300, and the recovery device 300 is used for recovering the soldering flux, which includes a recovery box body 31, a recovery filter net 32 and an exhaust pipe 33. A recovery inlet 310 is arranged on the side wall of the recovery box body 31, and the air outlet of the cooling suction fan is connected to the inside of the recovery box body 31 through the recovery inlet 310. The exhaust pipe 33 is fixed on the top of the recovery box body 31 and is connected to the inside of the recovery box body 31 for discharging the recovered gas. The recovery filter net 32 is fixed inside the recovery box body 31, the recovery filter net 32 is vertically arranged and is located between the recovery inlet 310 and the exhaust pipe 33. The soldering flux in the gas can be filtered by using the recovery filter net 32 to prevent it from being discharged through the exhaust pipe 33.

[0094] The recovery filter net 32 is inclined with respect to the air flow direction at the position of the recovery inlet 310, that is, the two are neither perpendicular nor parallel to each other. By using the inclination angle, the contact area between the recovery filter net 32 and the air flow can be increased, thereby improving the filtering effect.

[0095] There are multiple recovery filter nets 32, and they are arranged in parallel with each other. By using multiple recovery filter nets 32, the filtering effect can be further improved.

[0096] A discharge pipe (not shown in the figure) is arranged at the bottom of one end of the recovery box body 31, and the discharge pipe is connected to the inside of the recovery box body 31. A guide groove is arranged at the bottom of the recovery filter net 32. The guide groove is strip-shaped, and the end close to the discharge pipe is lower than the other end, so that the soldering flux on the filter net flows downward into the guide groove and then flows along the guide groove to the position of the guide pipe, and then the recovered soldering flux can be collected.

[0097] The recovery device further includes a recovery fan 34. The recovery fan 34 is fixed to the recovery box body 31. The air inlet of the recovery fan 34 is located outside the recovery box body 31, and the air outlet is located inside the recovery box body 31. A guide plate 35 is arranged between the air outlet of the recovery fan 34 and the bottom of the exhaust pipe 33. The guide plate 35 is located between the recovery fan 34 and the recovery filter net 32. One end of the guide plate 35 is connected to the recovery fan 34, and the other end is connected to the bottom of the exhaust pipe 33 to guide the air flow from the air outlet of the recovery fan 34 into the exhaust pipe 33. By arranging the recovery fan 34 and the guide plate 35, the air flow velocity at the exhaust pipe 33 can be increased, which is beneficial to the air in the recovery box body 31 to be discharged through the exhaust pipe 33, and the filtering and exhaust efficiency can be improved.

[0098] The bottom of the exhaust pipe 33 is divided into a first air outlet 331 and a second air outlet 332 by the guide plate 35. The first air outlet 331 is connected to the air outlet of the recovery fan 34. The cross-section of the first air outlet 331 is smaller than that of the second air outlet 332, so that the air flow velocity at the first air outlet 331 is larger, which is convenient for driving the air flow at the second air outlet 332.

[0099] In summary, although the present invention has been disclosed above in preferred embodiments, the above preferred embodiments are not intended to limit the present invention. Those of ordinary skill in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. An efficient and precise temperature-controlled reflow soldering device, characterized in that, It includes a step-by-step heating device, a cooling device and a recovery device connected in sequence; The step-by-step heating device comprises a plurality of heating modules, the plurality of heating modules are arranged at intervals in the longitudinal direction, and a partition cavity is arranged between two adjacent heating modules; each of the heating modules is provided with a heat source cavity and a heating cavity, the heat source cavity is used to provide heat energy and transport it to the heating cavity; the heating cavity and the heat source cavity are connected via a return channel, the return channel comprises a partition return channel and an inner return channel, the partition return channel and the inner return channel are both two, the two inner return channels are arranged in the transverse direction, and the two partition return channels are arranged in the longitudinal direction; the heating cavity A delivery port is formed between the partition cavity and the delivery port, and the delivery port is used for the circuit board to pass through; the partition return channel is arranged at the delivery port, and the partition return channel is in the shape of a slit extending in the transverse direction, and one end of the partition return channel in the vertical direction is located at the delivery port, and the other end is connected to the heat source cavity, so as to form an airflow flowing vertically into the heat source cavity at the delivery port, thereby forming a wind wall to block the air at the delivery port from flowing in the longitudinal direction, thereby reducing the air flow and heat interference between the heating cavity and the partition cavity at the delivery port; The cooling device comprises cooling modules, and there are more than two cooling modules, which are arranged at intervals in the longitudinal direction; an air suction channel is provided between two adjacent cooling modules; Each cooling module is provided with a cooling chamber on one side in the vertical direction, and a cooling air supply fan and a cooling air suction fan are provided on the other side. The air supply port of the cooling air supply fan is connected to the cooling chamber, and the air suction port of the cooling air suction fan is connected to the cooling chamber through the air suction channel to suck away the hot air in the cooling chamber; the air outlet of the cooling air suction fan is connected to the recovery device; The recovery device is used for recovering soldering flux.

2. The high-efficiency precision temperature-controlled reflow soldering equipment according to claim 1, characterized in that The heating module includes a heater, and the heater includes a housing, a heat-saturating component, a heating component and a heating fan; The heat-saturating assembly is fixed to the outer shell, and includes an inner shell, an air outlet plate and a heat-saturating plate; the inner shell and the outer shell are both in the shape of a cube with one side open, and the opening directions of the two are the same; the inner shell is fixed in the outer shell, and the heat source cavity is formed between the two; the partition return channel is located between the openings of the inner shell and the outer shell; the air outlet plate is fixed at the opening of the inner shell, and a heat-saturating cavity is formed between the two; the heat-saturating plate is located in the heat-saturating cavity, the heat-saturating plate is parallel to the air outlet plate and is arranged at intervals, and a plurality of through holes are provided on the air outlet plate and the heat-saturating plate; The heating component is disposed in the heat source cavity to provide heat energy; The heating fan is fixed to the outer shell, the air inlet of the heating fan is located in the heat source cavity, and the air outlet is connected to the heat-averaging cavity through a hot air duct, the hot air duct has an air outlet end facing the heat-averaging plate, the air outlet end is located on the side of the heat-averaging plate away from the air outlet plate, and the air outlet end is spaced apart from the heat-averaging plate.

3. The high-efficiency precision temperature-controlled reflow soldering equipment according to claim 2, wherein The heaters are arranged in pairs, the pair of heaters are arranged vertically and symmetrically, and the space between the pair of heaters forms a heating chamber.

4. The high-efficiency precision temperature-controlled reflow soldering equipment according to claim 1, characterized in that, The partition reflux channel is longitudinally divided into a first sub-channel and a second sub-channel; both the first sub-channel and the second sub-channel are slit-shaped; the first sub-channel is closer to the heating chamber than the second sub-channel; longitudinally, the size of the second sub-channel is smaller than that of the first sub-channel.

5. The high-efficiency precision temperature-controlled reflow soldering equipment according to claim 1, characterized in that, The cooling module includes a cooling frame, and both the cooling air blower and the cooling air suction fan are fixed to the cooling frame; The cooling frame is shell-shaped, and an air suction chamber is formed therein; An air inlet hole is provided on the side wall of the cooling frame, and the air inlet hole communicates the air suction chamber with the air suction channel. The air suction port of the cooling air suction fan is communicated to the air suction chamber, so that the air flow in the cooling chamber enters the air suction chamber through the air suction channel and the air inlet hole and is discharged.

6. The high-efficiency precision temperature-controlled reflow soldering equipment according to claim 5, wherein The cooling module further includes an air distribution assembly; the air distribution assembly is fixed to the cooling frame; the air distribution assembly includes an air distribution shell and an air distribution plate. The air distribution shell and the side wall of the cooling frame enclose an air distribution chamber; the air distribution shell includes a air supply plate, the air supply plate is arranged parallel to the air distribution plate, and a plurality of through holes are uniformly arranged on both of them; the air distribution plate is arranged in the air distribution chamber; the air supply port of the cooling air blower communicates with the air distribution chamber and faces the air distribution plate, so that the cooling air flow flows to the cooling chamber after passing through the air distribution plate and the air supply plate.

7. The high-efficiency precision temperature-controlled reflow soldering equipment according to claim 1, wherein, The air suction port of one of the cooling air suction fans is communicated to all the partition chambers.

8. The high-efficiency precision temperature-controlled reflow soldering equipment according to claim 1, characterized in that The recovery device includes a recovery box body, a recovery filter screen and an exhaust pipe; a recovery inlet is provided on the side wall of the recovery box body, and the air outlet of the cooling air suction fan is communicated to the inside of the recovery box body through the recovery inlet; the exhaust pipe is fixed on the top of the recovery box body and is communicated to the inside of the recovery box body for discharging the recovered gas; the recovery filter screen is fixed inside the recovery box body, the recovery filter screen is vertically arranged and is located between the recovery inlet and the exhaust pipe.

9. The high-efficiency precision temperature-controlled reflow soldering equipment according to claim 8, characterized in that The recovery filter screen is inclined with respect to the air flow direction at the recovery inlet.

10. The high-efficiency precision temperature-controlled reflow soldering equipment according to claim 8, characterized in that, The recovery device further includes a recovery fan, the recovery fan is fixed to the recovery box body, the air inlet of the recovery fan is located outside the recovery box body and the air outlet is located inside the recovery box body. A guide air plate is arranged between the air outlet of the recovery fan and the bottom of the exhaust pipe. The guide air plate is located between the recovery fan and the recovery filter screen, and one end of it is connected to the recovery fan and the other end is connected to the bottom of the exhaust pipe to guide the air flow from the air outlet of the recovery fan into the exhaust pipe.

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