Circuit board blow-drying and drying device

Abstract

The utility model discloses a circuit board blow-drying and drying device, which comprises a transmission assembly, a blow-drying groove body, a blow-drying fan, a plurality of blow-drying air knives, a heater, a drying fan, a plurality of drying air knives and a drying groove body, and is characterized in that the transmission assembly comprises a roller group, the roller group penetrates through the blow-drying groove body and the drying groove body, and the blow-drying fan extracts air and sprays the air through the blow-drying air knives; the heater heats air in the drying groove body, and the drying fan extracts the air in the drying groove body and sprays the air out through the drying air knife. The plurality of blow-drying air knives are symmetrically arranged on the two sides of the circuit board in the thickness direction, the plurality of drying air knives are asymmetrically arranged on the two sides of the circuit board in the thickness direction, the number of the drying air knives is large, and the interval is longer; the air injection flow speed of the blow-drying air knife is higher than that of the drying air knife, the blow-drying air knife is used for blowing away accumulated water on the circuit board, and the drying air knife is used for drying the surface of the circuit board. The device can remove accumulated water in holes of the circuit board in advance and balance wind pressure and heat borne by all areas of the circuit board.

Description

Technical Field

[0001] The utility model relates to the field of printed circuit board production and manufacturing, in particular to a device for drying and baking a printed circuit board. Background Art

[0002] During the production and manufacturing of printed circuit boards, there are a large number of processes that require spraying or soaking. Before completing the spraying or soaking process and transferring to the next process, the printed circuit board will be attached with accumulated water, which will affect the stability of the printed circuit board product and the transfer between printed circuit board processes. Therefore, it is necessary to remove the accumulated water on the printed circuit board and perform a drying operation.

[0003] The existing printed circuit board drying device blows off the accumulated water on the printed circuit board surface through a jet air knife, and then dries the printed circuit board surface through devices such as baking lamps and sponge rollers, or only dries the board surface with high-temperature hot air. However, the above methods of drying the board surface have the following problems: First, the drying effect is not good and the efficiency of the baking lamp is not high. Second, the placement position of the jet air knife along the conveying direction of the printed circuit board is not reasonably arranged, and the wind pressure or the heat of the hot air received by each area of the printed circuit board is different during the blowing and drying process, resulting in problems such as board warping due to abnormal temperature of the printed circuit board and conveying deviation resulting in board jamming. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a device for drying and baking a printed circuit board that can remove the accumulated water in the holes of the printed circuit board in advance and make the wind pressure and heat received by each area of the printed circuit board balanced.

[0005] A device for drying and baking a printed circuit board provided by the utility model includes a transmission component, a drying tank body, a drying fan and a plurality of drying air knives. The transmission component includes a roller group arranged in sequence along the conveying direction of the printed circuit board. The roller group passes through the drying tank body. The drying air knives are arranged inside the drying tank body. The drying fan is used to extract air and pump it out to be ejected by the plurality of drying air knives. The drying air knives are used to blow air on the printed circuit board conveyed along the roller group. It further includes a heater, a drying fan and a plurality of drying air knives. Along the conveying direction, a closed drying tank body is further included downstream of the drying tank body. The roller group passes through the drying tank body. The heater, the drying fan and the plurality of drying air knives are all arranged inside the drying tank body. The heater is used to heat the air inside the drying tank body. The drying fan is used to extract the air inside the drying tank body and pump it out to be ejected by the drying air knives. The air outlet ends of the drying air knives and the drying air knives are closer to the printed circuit board than the side of the roller group away from the printed circuit board. The plurality of drying air knives are symmetrically arranged on both sides of the printed circuit board thickness. The plurality of drying air knives are asymmetrically arranged on both sides of the printed circuit board thickness. The number of drying air knives is more than that of the drying air knives. Along the conveying direction, the distance between two adjacent drying air knives on the same side of the printed circuit board is greater than the distance between two adjacent drying air knives on the same side of the printed circuit board. The jet air velocity of the drying air knives is higher than that of the drying air knives. The drying air knives are used to blow off the accumulated water on the printed circuit board, and the drying air knives are used to dry the printed circuit board surface.

[0006] As can be seen from the above solution, this device is provided with two tanks, a blowing-drying tank and a drying tank. First, the accumulated water in the holes of the circuit board is blown out and most of the accumulated water on the board surface is blown off, and then the board surface is completely dried through the drying tank. The drying tank itself is a closed space, and the heated air for drying always circulates inside the drying tank, without causing waste of heat. The blowing air knife and the drying air knife are arranged very close to the board surface of the circuit board, which is beneficial to the blowing-drying and drying operations of the circuit board. Since the blowing air knife is used to blow out the accumulated water in the holes of the circuit board, its jet flow rate is higher than that of the drying air knife, and it should be a higher jet flow rate, which will generate a relatively large air pressure on the board surface of the circuit board. Therefore, the blowing air knives are symmetrically arranged on both sides of the circuit board thickness to balance the air pressure on both sides well and prevent the circuit board from shifting. In addition, since the air flow rate of the drying air knife is not high but the temperature is high, in order to prevent the heat of the jet from being too concentrated on the board surface of the circuit board and causing abnormal expansion and contraction of the circuit board, the drying air knives are arranged asymmetrically and staggeredly on both sides of the circuit board thickness. And, in order to prevent local overheating during the drying process and to ensure a good drying effect, the distance between the drying air knives is increased and the number is increased, so that the drying tank is longer than the blowing-drying tank, and an excellent drying effect can be achieved.

[0007] Preferably, along the conveying direction, a plurality of drying air knives are alternately arranged on both sides of the circuit board thickness in sequence, and the distance between two adjacent drying air knives arranged alternately is equal.

[0008] Thus, by alternately arranging a plurality of drying air knives on both sides of the circuit board thickness in sequence and keeping the distance between two adjacent drying air knives consistent, the circuit board can be heated evenly everywhere and the drying effect can be better achieved.

[0009] Preferably, the air outlet end of the blowing air knife is provided with a direct jet port and an inclined jet port. The blowing air knife jets perpendicularly to the board surface of the circuit board through the direct jet port, and the blowing air knife jets obliquely at an angle to the board surface of the circuit board through the inclined jet port.

[0010] Thus, the direct jet port and the inclined jet port can blow out the accumulated water in the holes of the circuit board from various angles to prevent the remaining of the accumulated water.

[0011] Preferably, it further includes a blowing-drying shunt box and a drying shunt box. The blowing-drying shunt box includes a first air connection port connected to the blowing-drying fan and a plurality of first shunt ports respectively connected to the blowing air knives one by one. The drying shunt box includes a second air connection port connected to the drying fan and a plurality of second shunt ports respectively connected to the drying air knives one by one.

[0012] Thus, by means of the blowing-drying shunt box and the drying shunt box, a single air pump can evenly pump air to multiple air knives.

[0013] Preferably, downstream of the drying tank along the conveying direction, there is also an electrostatic elimination tank. The roller group passes through the electrostatic elimination tank, and an ion spray head is arranged in the electrostatic elimination tank. The ion spray head is used to spray static elimination ions on the circuit board.

[0014] It can be seen that after drying, due to the friction of the air flow, static electricity will remain on the surface of the circuit board, which may cause potential safety hazards. The ion spray head spraying static elimination ions can effectively remove the static electricity on the surface of the circuit board.

[0015] Preferably, there are also a first filter component and a second filter component. The first filter component is connected to the air drying blower and is used to filter the air pumped in by the air drying blower. The second filter component is connected to the drying blower and is used to filter the air pumped in by the drying blower.

[0016] It can be seen that when the air drying blower or the drying blower sucks in air, it needs to pass through the first filter component or the second filter component first to avoid damage to the surface of the circuit board by impurities in the high-speed jet air flow.

[0017] Further, the first filter component includes a primary filter section and a high-efficiency filter section arranged in sequence along the air flow direction. The filtering accuracy of the high-efficiency filter section is more than ten times that of the primary filter section.

[0018] It can be seen that since the air drying blower directly sucks in air from the outside, the content of impurities in the gas is relatively high. Through the hierarchical filtration of the primary filter section and the high-efficiency filter section with a filtering accuracy difference of more than ten times, the content of impurities can be effectively reduced.

[0019] Further, a differential pressure gauge is arranged in the first filter component. The differential pressure gauge is used to detect the air pressure before flowing into the primary filter section, the air pressure between the primary filter section and the high-efficiency filter section, and the air pressure after flowing out of the high-efficiency filter section and calculate the air pressure difference between any two of the three.

[0020] It can be seen that the differential pressure gauge can measure the air pressure at various parts of the first filter component and calculate the difference. When the air pressure difference is too large, it indicates that the first filter component is dirty and the filter element needs to be replaced to prevent insufficient jet air flow of the air knife due to failure. Description of the Drawings

[0021] The present invention will be further described with reference to the accompanying drawings. However, the embodiments in the drawings do not constitute any limitation to the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to the following drawings.

[0022] Figure 1 is a structural diagram of an embodiment of the present invention.

[0023] Figure 2 isFigure 1 Enlarged view of location A.

[0024] Figure 3 is Figure 1 Enlarged view of location B. Detailed implementation manners

[0025] The technical solutions of the present utility model will be clearly and completely described below in conjunction with the accompanying drawings. Apparently, the described embodiments are part of the embodiments of the present utility model, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts fall within the scope of protection of the present utility model.

[0026] For technologies, methods and devices known to those of ordinary skill in the relevant fields, detailed discussions may not be made, but in appropriate cases, the said technologies, methods and devices should be regarded as part of the description.

[0027] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present utility model.

[0028] This embodiment provides a circuit board drying and baking device, including a transmission assembly, a drying tank 2, a drying fan 3, a plurality of drying air knives 4, a baking tank 5, a baking fan 6, a heater 7, an electrostatic elimination tank 8 and a plurality of baking air knives 9. The transmission assembly includes a roller group 11 arranged in sequence along the circuit board transmission direction. The circuit board is transmitted in the middle of the upper and lower rows of roller groups 11. The roller group 11 is sequentially passed through the drying tank 2, the baking tank 5 and the electrostatic elimination tank 8 along the circuit board transmission direction. As Figure 1 shown, the drying air knives 4 are arranged inside the drying tank 2 and there are a total of eight. Each drying air knife 4 is arranged side by side and perpendicularly to the circuit board transmission direction. The eight drying air knives 4 are symmetrically arranged in two groups on both sides of the board thickness of the circuit board. And the roller group 11 is missing rollers at the positions where the drying air knives 4 are arranged for avoidance, so that the air outlet end of the drying roller group 11 is lower than the side of the roller group 11 away from the circuit board. The drying fan 3 is used to extract air from the outside and connect it to the first air inlet 101 of the drying shunt box 10, and then through a plurality of first shunt ports 102 of the drying shunt box 10, each drying air knife 4 is connected one by one, so that the circuit board can be blown with air to remove water through the drying air knives 4.

[0029] The drying tank body 5 is a closed space. The circuit board can be dried by passing through the drying tank body 5. Among them, a heater 7, a drying fan 6 and several drying air knives 9 are arranged inside the drying tank body 5. The heater can heat the air inside the drying tank body 5 to make the air inside the drying tank body 5 reach a relatively high temperature. The drying fan 6 can extract the hot air with a high temperature from the drying tank body 5. Similar to the blowing fan 3, it also includes a drying shunt box 11. The drying fan 6 is connected to the second air inlet 111 of the drying shunt box 11, and then is connected to each drying air knife 9 through several second shunt ports 112 of the drying shunt box 11 one by one. Finally, the circuit board is dried by jetting air through the drying air knives 9, and the hot air always circulates inside the drying tank body 5. Similar to the blowing air knife 4, there are a total of twelve drying air knives 9. Each drying air knife 9 is arranged side by side perpendicular to the circuit board conveying direction, and can jet air evenly on a relatively wide circuit board. As Figure 1 shown, the twelve drying air knives 9 are alternately arranged on both sides of the circuit board thickness in sequence. The distance between two adjacent drying air knives 9 arranged alternately is equal, that is, the six drying air knives 9 below the circuit board are arranged below the circuit board at the middle position between two adjacent drying air knives 9 above the circuit board.

[0030] In addition, as Figure 2 shown, each blowing air knife 4 has several positive jet ports 41 and inclined jet ports 42, and can jet air vertically or obliquely at an angle on the circuit board surface. The positive jet ports 41 and inclined jet ports 42 of the blowing air knife 4 are smaller than those of the drying air knife 9, and the air flow velocity is faster, so that the accumulated water can be more effectively driven out of the circuit board holes. The drying air knife 9 is larger and the air flow velocity is slower, but the air flow temperature is relatively high, generally set to 80 to 95 degrees Celsius. In order to prevent the heat from concentrating at one place during drying and to achieve a better drying effect, the number of drying air knives 9 is more, the spacing is larger, the length of the drying tank body 5 along the conveying direction is longer, and a temperature measuring device is also arranged in the drying tank to monitor the air temperature in the drying tank in real time. In addition, a transmission reduction gear and a transmission device are also connected to the roller group 11 to adjust the rotation speed of the roller group 11 and better achieve the drying effect.

[0031] As Figure 1 shown, along the conveying direction, an electrostatic elimination tank body 8 is also arranged behind the drying tank body 5, and an ion spray head 81 is arranged inside it, which can spray static elimination ions on the upper and lower surfaces of the circuit board.

[0032] A circuit board blowing and drying device provided by this embodiment further includes a first filter assembly 12 and a second filter assembly 13. As Figure 1As shown, the first filtering component 12 is connected to the drying blower 3. The air pumped by the drying blower 3 is filtered by the first filtering component 12 and then output to the drying air knife 4. The second filtering component 13 is connected to the drying fan 6. The air pumped by the drying fan 6 is filtered by the second filtering component 13 and then output to the drying air knife 9. In addition, the first filtering component 12 includes a primary filtering part 121 and a high-efficiency filtering part 122 arranged in sequence along the air flow direction of the air inhaled by the drying blower 3. Among them, the primary filtering part 121 can first filter out impurity particles with a size of more than 70 microns, and the high-efficiency filtering part 122 can filter the air filtered by the primary filtering part 121 again. It can filter out impurity particles with a size of more than 0.3 microns. When the air filtered in two stages is sprayed at high speed on the circuit board surface by the drying air knife 4, the damage to the board surface will be reduced.

[0033] In addition, a differential pressure gauge 123 is also provided in the first filtering component 12. It can detect the air pressure before flowing into the primary filtering part 121, the air pressure between the primary filtering part 121 and the high-efficiency filtering part 122, and the air pressure after flowing out of the high-efficiency filtering part 122, and can calculate the difference between two adjacent air pressures along the air flow direction. When the difference is too large, it indicates that the primary filtering part 121 or the high-efficiency filtering part 122 is dirty and needs to be replaced.

[0034] The above embodiments only represent one implementation mode of the present utility model, and its description is relatively specific and detailed, but it cannot be understood as a limitation on the scope of the utility model patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present utility model, several deformations and improvements can still be made, and these all belong to the protection scope of the present utility model. Therefore, the protection scope of the present utility model patent shall be subject to the appended claims.

Claims

1. A circuit board drying and baking device, comprising a transmission assembly, a drying tank, a drying fan and a plurality of drying air knives. The transmission assembly includes a roller group arranged in sequence along the circuit board transmission direction. The roller group penetrates through the drying tank. The drying air knives are arranged inside the drying tank. The drying fan is used for extracting air and pumping it out to be ejected by the plurality of drying air knives. The drying air knives are used for blowing air on the circuit board conveyed along the roller group. It is characterized in that It further includes a heater, a baking fan and a plurality of baking air knives. Along the transmission direction, a sealed baking tank is further included downstream of the drying tank. The roller group penetrates through the baking tank. The heater, the baking fan and the plurality of baking air knives are all arranged inside the baking tank. The heater is used for heating the air inside the baking tank. The baking fan is used for extracting the air inside the baking tank and pumping it out to be ejected by the baking air knives. The air outlet ends of the drying air knives and the baking air knives are closer to the circuit board than the side of the roller group away from the circuit board. A plurality of the drying air knives are symmetrically arranged on both sides of the circuit board thickness. A plurality of the baking air knives are asymmetrically arranged on both sides of the circuit board thickness. The number of the baking air knives is more than that of the drying air knives. Along the transmission direction, the distance between two adjacent baking air knives on the same side of the circuit board is greater than the distance between two adjacent drying air knives on the same side of the circuit board. The jet flow velocity of the drying air knives is higher than that of the baking air knives. The drying air knives are used for blowing off the accumulated water on the circuit board. The baking air knives are used for drying the circuit board surface.

2. The drying and baking device for circuit boards according to claim 1, characterized in that, Along the transmission direction, a plurality of the baking air knives are alternately arranged on both sides of the circuit board thickness in sequence, and the distance between two adjacent alternately arranged baking air knives is equal.

3. The circuit board drying and baking device according to claim 2, characterized in that, The air outlet end of the drying air knife is provided with a positive jet port and an inclined jet port. The drying air knife jets air perpendicular to the circuit board surface through the positive jet port, and jets air obliquely at an angle with the circuit board surface through the inclined jet port.

4. A circuit board drying and baking device according to claim 2, characterized in that, It further includes a drying shunt box and a baking shunt box. The drying shunt box includes a first air connection port connected to the drying fan and a plurality of first shunt ports connected to the drying air knives one by one. The baking shunt box includes a second air connection port connected to the baking fan and a plurality of second shunt ports connected to the baking air knives one by one.

5. A circuit board drying and baking device according to claim 4, characterized in that, Along the transmission direction, an electrostatic elimination tank is further included downstream of the baking tank. The roller group penetrates through the electrostatic elimination tank. An ion spray head is arranged inside the electrostatic elimination tank. The ion spray head is used for spraying static elimination ions on the circuit board.

6. A circuit board drying and baking device according to any one of claims 1 to 5, characterized in that, It further includes a first filtering component and a second filtering component. The first filtering component is connected to the drying fan and is used for filtering the air pumped into by the drying fan. The second filtering component is connected to the baking fan and is used for filtering the air pumped into by the baking fan.

7. A circuit board drying and baking device according to claim 6, characterized in that, The first filtering component includes a primary filtering part and a high-efficiency filtering part arranged in sequence along the air flow direction. The filtering accuracy of the high-efficiency filtering part is more than ten times that of the primary filtering part.

8. A circuit board drying and baking device according to claim 7, characterized in that, A differential pressure gauge is provided inside the first filtering component. The differential pressure gauge is used to detect the air pressure before flowing into the primary filtering part, the air pressure between the primary filtering part and the high-efficiency filtering part, and the air pressure after flowing out of the high-efficiency filtering part, and calculate the air pressure difference between any two of the three.

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