Hot air drying device for PCB

Abstract

The hot air drying device for the PCB comprises a drying box, a draught fan, a heating box and a hot air filter, the drying box is provided with a drying cavity, a hot air inlet and a circulating air outlet, the drying cavity is used for drying the PCB, the draught fan is connected with a three-way pipe, a first inlet of the three-way pipe is used for introducing fresh air, and a second inlet of the three-way pipe is connected to the circulating air outlet; a first outlet of the three-way pipe is connected to an air inlet of the fan, the heating box comprises a box body, a heater and a first temperature probe, the heater and the first temperature probe are arranged in the box body, the air inlet of the box body is connected to an air outlet of the fan, a hot air outlet of the box body is connected to the hot air inlet, and the first temperature probe is used for monitoring the temperature in the box body and controlling starting and stopping of the heater in a feedback mode. And the hot air filter is arranged on a path of hot air from the hot air outlet of the box body to the PCB. Therefore, while the quality of a PCB finished product can be ensured, the device has the characteristics of wide applicable temperature range and low operation energy consumption.

Description

Technical Field

[0001] The present application relates to the technical field of circuit board manufacturing, and in particular to a hot air drying device for PCB. Background Art

[0002] There are many processes that use wet process in the production and manufacturing process of PCB. When the semi-finished products of the wet process are out of the board, they usually need to be dried with hot air before they can be transported to the next process for further production and packaging. There are currently two commonly used hot air drying methods. One is the internal circulation heating method, which has high requirements for thermal insulation effect and has a high risk of overheating. Therefore, it is only suitable for low heat demand environments and has a limited scope of application. The other is the method of simultaneous internal and external air heating. Although it has a wide range of applicable temperature, it has low temperature control accuracy and high operating energy consumption, which is out of the development rhythm of green smart manufacturing in the manufacturing industry. At the same time, when using hot air to dry semi-finished boards, particulate impurities in the hot air can easily contaminate the semi-finished boards and affect the quality of the finished PCB. Utility Model Content

[0003] In order to solve at least one of the above technical problems, the present application provides a hot air drying device for PCB, which can ensure the quality of PCB finished products while having the characteristics of a wide applicable temperature range, precise temperature control and low operating energy consumption.

[0004] According to an embodiment of the present application, a hot air drying device for PCB is provided, comprising:

[0005] A drying box, wherein the drying box is provided with a drying chamber, a hot air inlet and a circulating air outlet, the drying chamber is used to dry the PCB, the hot air inlet and the circulating air outlet are arranged at intervals and are respectively connected to the drying chamber;

[0006] A fan, wherein the fan is connected to a three-way pipe, the three-way pipe has a first inlet, a second inlet and a first outlet, the first inlet is used to introduce fresh air, the second inlet is connected to the circulating air outlet, and the first outlet is connected to the air inlet of the fan;

[0007] A heating box, the heating box comprising a box body, a heater and a first temperature probe arranged in the box body, the air inlet of the box body being connected to the air outlet of the fan, the box body being provided with a hot air outlet, the hot air outlet being connected to the hot air inlet, the first temperature probe being used to monitor the temperature in the box body and feedback control the start and stop of the heater; and

[0008] A hot air filter is arranged on the path of hot air from the hot air outlet to the PCB.

[0009] As an optional implementation, in an embodiment of the present application, the hot air drying device for PCB also includes a first regulating valve, which is arranged at one end of the three-way pipe close to the first inlet, and the first regulating valve is used to adjust the air intake volume of the first inlet.

[0010] As an optional implementation, in an embodiment of the present application, the hot air drying device for PCB also includes a second temperature probe, which is arranged in the drying chamber, and the second temperature probe is communicatively connected to the first regulating valve, and the second temperature probe is used to monitor the temperature in the drying chamber and feedback control the opening of the first regulating valve.

[0011] As an optional implementation, in an embodiment of the present application, the hot air drying device for PCB also includes a second regulating valve, which is arranged at one end of the three-way pipe close to the second inlet, and the second regulating valve is used to adjust the air intake volume of the second inlet.

[0012] As an optional implementation, in an embodiment of the present application, the hot air drying device for PCB also includes a wind knife and a plate walking mechanism, the wind knife and the plate walking mechanism are located in the drying box, and the hot air filter is installed between the hot air outlet and the hot air inlet, the hot air inlet is connected to the air inlet of the wind knife, and the air outlet of the wind knife is arranged corresponding to the plate walking mechanism, and the plate walking mechanism is used to convey the PCB.

[0013] As an optional implementation, in an embodiment of the present application, the plate walking mechanism includes a first roller group, a second roller group and a driving part, the driving part is used to drive the first roller group and the second roller group to rotate relative to each other, the first roller group and the second roller group are arranged at intervals to form a conveying space for accommodating PCBs, the first roller group includes a plurality of first rollers arranged in sequence at intervals along its axial direction, the second roller includes a plurality of second rollers arranged in sequence at intervals along its axial direction, the plurality of first rollers correspond one-to-one to the plurality of second rollers, and the air outlet of the wind knife is arranged corresponding to the gap between two adjacent first rollers or two adjacent second rollers.

[0014] As an optional embodiment, in an embodiment of the present application, the driving part includes a first rotating member, a second rotating member and a support plate, the support plate is provided with a slide groove, the first rotating member is connected to the first roller group through a first rotating shaft, the second rotating member is connected to the second roller group through a second rotating shaft, the first rotating shaft and the second rotating shaft are passed through the slide groove, so that the first rotating member and the first roller group are respectively arranged on both sides of the support plate, the second rotating member and the second roller group are respectively arranged on both sides of the support plate, and the first rotating shaft and the second rotating shaft are slidable along the extension direction of the slide groove.

[0015] As an optional implementation, in an embodiment of the present application, the hot air drying device for PCB also includes a wind pressure gauge, which is installed on the hot air filter and is communicatively connected to the fan, and the wind pressure gauge is used to monitor and adjust the wind pressure at the air outlet of the fan.

[0016] As an optional implementation, in an embodiment of the present application, the hot air drying device for PCB further includes a fresh air filter, and the outlet of the fresh air filter is connected to the first inlet.

[0017] As an optional implementation, in an embodiment of the present application, the drying box is further provided with an exhaust gas discharge port connected to the drying chamber, and the exhaust gas discharge port is used to connect to an exhaust system to discharge the exhaust gas in the drying chamber.

[0018] Compared with the prior art, the beneficial effects of this application are:

[0019] A hot air drying device for PCB provided in an embodiment of the present application adopts a method of mixing fresh air at room temperature from the external environment and circulating air with residual heat in a drying box, so as to have a larger applicable temperature range. A three-way pipe is arranged at the air inlet of the fan, and the first inlet of the three-way pipe is used to introduce fresh air at room temperature, and the second inlet of the three-way pipe is connected to the circulating air outlet of the drying box, so that the circulating air with residual heat in the drying box can enter the fan. After the fresh air and the circulating air are mixed in the fan, they enter the heating box and take away the operating heat inside the fan. After being heated in the heating box, they enter the drying chamber through the hot air outlet and the hot air inlet in sequence to dry. Dry PCB, because the hot air drying device for PCB of the present application utilizes the circulating waste heat in the drying box and the operating heat inside the fan, it can improve the utilization rate of heat to reduce the energy consumption of heating fresh air into hot air. At the same time, by monitoring the temperature in the box through the first temperature probe and feedback controlling the start and stop of the heater, it can not only accurately control the temperature of the hot air supplied to the drying box, reduce the operating energy consumption of the hot air drying device, but also monitor the process temperature, protect the PCB in the drying chamber, and avoid the situation where the PCB is overheated and damaged due to the hot air temperature in the drying chamber exceeding the working temperature, thereby affecting the quality of the PCB finished product. In addition, by adopting the scheme provided in the embodiment of the present application, the normal temperature fresh air of the external environment and the circulating air with residual heat in the drying box are simultaneously inhaled and mixed by the fan. By adjusting the ratio of fresh air and circulating air and the heating temperature of the heater, the temperature of the hot air input into the drying chamber can be adjusted to accurately control the temperature in the drying chamber, so that the hot air drying device for PCB has a larger applicable temperature range. In addition, by arranging a hot air filter on the path of the hot air from the hot air outlet of the heating box to the PCB located in the drying box, the airflow used to dry the PCB can be filtered to remove particulate impurities in the airflow, thereby improving the purity of the airflow entering the drying chamber and reducing particulate impurities attached to the semi-finished board, thereby further improving the quality of the finished PCB. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are used to provide further understanding of the technical solution of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the present application and do not constitute a limitation on the technical solution of the present application.

[0021] Figure 1 It is a structural schematic diagram of a hot air drying device for PCB disclosed in an embodiment of the present application;

[0022] Figure 2 It is a front view of the board walking mechanism disclosed in the embodiment of the present application;

[0023] Figure 3 It is a right side view of the board walking mechanism disclosed in the embodiment of the present application;

[0024] Figure 4It is a schematic diagram of the electrical control relationship of the hot air drying device for PCB disclosed in the embodiment of the present application.

[0025] Reference numerals:

[0026] 1. Hot air drying device for PCB; 101. Drying box; 1011. Exhaust gas outlet; 102. Fan; 103. Heating box; 1031. Box body; 1032. Heater; 1033. First temperature probe; 104. Hot air filter; 105. Control mechanism; 106. Three-way pipe; 1061. First inlet; 1062. Second inlet; 1063. First outlet; 107. Wind pressure gauge; 108. Fresh air filter; 109. Fresh air mixing box; 110. First regulating valve; 111. Second temperature probe; 112. Second regulating valve; 113. Wind knife; 114. Board walking mechanism; 1141. First roller group; 1142. Second roller group; 1143. Driving part; 11431. First rotating member; 11432. Second rotating member; 11433. Support plate. DETAILED DESCRIPTION

[0027] This section will describe in detail the specific embodiments of the present application. The preferred embodiments of the present application are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present application, but it cannot be understood as a limitation on the scope of protection of the present application.

[0028] In the description of the present application, it should be understood that descriptions involving orientation, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0029] In the description of this application, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed", etc. are understood to exclude the number itself, and "above", "below", "within", etc. are understood to include the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0030] In the description of this application, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in this application based on the specific content of the technical solution.

[0031] The technical solution of the present application will be further described below in conjunction with embodiments and drawings.

[0032] Please also read Figures 1 to 4 The embodiment of the present application provides a hot air drying device 1 for PCB, including a drying box 101, a fan 102, a heating box 103, a hot air filter 104 and a control mechanism 105. The drying box 101 is provided with a drying chamber, a hot air inlet and a circulating air outlet. The drying chamber is used to dry the PCB. The hot air inlet and the circulating air outlet are arranged at intervals and are respectively connected to the drying chamber. The fan 102 is connected to a three-way pipe 106. The three-way pipe 106 has a first inlet 1061, a second inlet 1062 and a first outlet 1063. The first inlet 1061 is used to introduce fresh air, and the second inlet 1062 is connected to Circulating air outlet, the first outlet 1063 is connected to the air inlet of the fan 102, the heating box 103 includes a box body 1031 and a heater 1032 and a first temperature probe 1033 arranged in the box body 1031, the air inlet of the box body 1031 is connected to the air outlet of the fan 102, the box body 1031 is provided with a hot air outlet, the hot air outlet is connected to the hot air inlet, the hot air filter 104 is arranged on the path of the hot air from the hot air outlet to the PCB located in the drying box 101, and the first temperature probe 1033 is used to monitor the temperature in the box body 1031 and feedback control the start and stop of the heater 1032.

[0033] In this way, by arranging the three-way pipe 106 at the air inlet of the fan 102, the first inlet 1061 of the three-way pipe 106 is used to introduce fresh air at room temperature, and the second inlet 1062 of the three-way pipe 106 is connected to the circulating air outlet of the drying box 101, so that the circulating air with residual heat in the drying box 101 can enter the fan 102, and the fresh air and the circulating air are mixed in the fan 102 and enter the heating box 103 and take away the operating heat inside the fan 102. After being heated in the heating box 103, they enter the drying chamber through the hot air outlet and the hot air inlet in sequence to dry the PCB. The device 1 utilizes the circulating waste heat in the drying box 101 and the operating heat inside the fan 102, which can improve the utilization rate of heat to reduce the energy consumption of heating the fresh air into hot air. At the same time, the temperature in the box 1031 is monitored by the first temperature probe 1033 and the start and stop of the heater 1032 are feedback-controlled, which can not only accurately control the temperature of the hot air supplied to the drying box 101, reduce the operating energy consumption of the hot air drying device, but also monitor the process temperature, protect the PCB in the drying chamber, and avoid the situation where the PCB is overheated and damaged due to the hot air temperature in the drying chamber exceeding the working temperature, thereby affecting the quality of the PCB finished product. In addition, by adopting the solution provided in the embodiment of the present application, the normal temperature fresh air of the external environment and the circulating air with residual heat in the drying box 101 are simultaneously inhaled and mixed by the fan 102. By adjusting the ratio of the fresh air and the circulating air and the heating temperature of the heater 1032, the temperature of the hot air input into the drying chamber can be adjusted to accurately control the temperature in the drying chamber, so that the hot air drying device 1 for PCB has a larger applicable temperature range. In addition, by arranging a hot air filter 104 on the path of the hot air from the hot air outlet of the heating box 103 to the PCB located in the drying box 101, the airflow used to dry the PCB can be filtered to remove particulate impurities and dust in the airflow, thereby improving the purity of the airflow entering the drying chamber, reducing particulate impurities and dust attached to the semi-finished board, and further improving the quality of the finished PCB.

[0034] In some embodiments, the hot air drying device 1 for PCB further includes a control mechanism 105, which is communicatively connected to the fan 102, the heater 1032 and the first temperature probe 1033, respectively. The control mechanism 105 is used to receive and respond to the signal fed back by the first temperature probe 1033, so as to control the heater 1032 to start when the real-time temperature detected by the first temperature probe 1033 is less than the preset low temperature value, and to control the heater 1032 to stop when the real-time temperature detected by the first temperature probe 1033 is greater than the preset high temperature value. Thus, the hot air drying device 1 for PCB can be integrated with a control unit, which is beneficial to the functional integration of the hot air drying device 1 for PCB and improves the reliability of the hot air drying device 1 for PCB.

[0035] It can be understood that in other embodiments, the control mechanism can also be external or independently provided from the hot air drying device 1 for PCB.

[0036] In some embodiments, the hot air drying device 1 for PCB further includes a wind pressure gauge 107 , which is installed on the hot air filter 104 and is communicatively connected to the fan 102 , and is used to monitor and adjust the wind pressure at the air outlet of the fan 102 .

[0037] In this way, the air pressure at the air outlet of the fan 102 can be controlled within a preset range, which can help reduce the impact of hot air on the hot air filter 104, and avoid the situation where the hot air, under the action of the wind pressure, carries away pollutants such as particulate impurities and dust attached to the hot air filter 104, thereby reducing the purity of the air flow and affecting the quality of the finished PCB products. On the other hand, the air intake at the hot air inlet can be adjusted to help control the temperature of the drying box 101, making the temperature control of the drying box 101 more flexible.

[0038] Optionally, the drying box 101 is further provided with an exhaust gas outlet 1011 connected to the drying chamber, and the exhaust gas outlet 1011 is used to connect to the exhaust system to discharge the exhaust gas in the drying chamber, thereby facilitating the cleanliness of the circulating air in the drying box 101, improving the cleanliness of the PCB drying environment, and further facilitating the quality of the PCB finished product.

[0039] Optionally, the exhaust gas outlet 1011 is provided with a control valve, which is used to control the air flow rate of the exhaust gas outlet to control the exhaust gas discharge amount, which is conducive to achieving timed and quantitative exhaust gas discharge, thereby ensuring the cleanliness of the circulating air in the drying box 101.

[0040] In some embodiments, the hot air drying device 1 for PCB further includes a fresh air filter 108, and the outlet of the fresh air filter 108 is connected to the first inlet 1061. Thus, the fresh air entering the fan 102 can be filtered to improve the purity of the fresh air, so as to further improve the purity of the hot air after the fresh air and the circulating air are mixed and heated.

[0041] Optionally, the hot air drying device 1 for PCB also includes a fresh air mixing box 109, the inlet of the fresh air mixing box 109 is connected to the outlet of the fresh air filter 108 through a quick connector, and the outlet of the fresh air mixing box 109 is connected to the first inlet 1061 of the three-way pipe 106. The filtered fresh air is stored in the fresh air mixing box 109 to provide a pure fresh air source for the fan 102.

[0042] Optionally, the fresh air mixing box 109 can be installed in the drying box 101 so that the fresh air can be heated by the ambient temperature in the drying chamber after entering the fresh air mixing box 109, which is beneficial to reduce the energy consumption required by the heating box 103 when heating the mixed air, thereby reducing the operating energy consumption of the hot air drying device 1 for PCB.

[0043] It is understandable that in other embodiments, the fresh air mixing box 109 may not pass through the drying box 101, so as to help maintain the initial temperature of the fresh air, thereby helping to reduce the minimum temperature of the hot air input into the drying chamber.

[0044] In some embodiments, it can be known from the above that the fresh air introduced into the first inlet 1061 of the three-way pipe 106 is ambient air at normal temperature, and the circulating air with residual heat in the drying box 101 is introduced into the second inlet 1062, so the mixed air outputted from the first outlet 1063 of the three-way pipe 106 has an initial temperature, and the temperature of the mixed air rises after the operating heat inside the fan 102 is taken away by the fan 102, so that the mixed air before being heated by the heating box 103 also has a certain temperature. Under certain conditions, the mixed air that has not been heated by the heating box 103 can also meet the requirements of the drying box 101 for the temperature of the hot air introduced, and the heating box 103 can be dried without being turned on. By adjusting the mixing ratio of the fresh air and the circulating air, the initial temperature of the mixed air can be adjusted to adjust the temperature of the mixed air outputted through the air outlet of the fan 102 and not heated by the heating box 103, so that the minimum temperature of the hot air input into the drying box 101 can be controlled to further expand the applicable temperature range of the hot air drying device 1 for PCB.

[0045] Based on this, the hot air drying device 1 for PCB further includes a first regulating valve 110, which is disposed at one end of the three-way pipe 106 close to the first inlet 1061, and is used to adjust the air intake of the first inlet 1061. In this way, by adjusting the opening of the first regulating valve 110 to adjust the fresh air intake of the first inlet 1061, the ratio of fresh air and circulating air in the mixed air can be adjusted. When the fresh air intake is large and the proportion of circulating air in the mixed air is small, the initial temperature of the mixed air is low, so that the mixed air output through the air outlet of the fan 102 and not heated by the heating box 103 has a lower temperature. By controlling the heating box 103 to shut down, the temperature of the hot air entering the hot air inlet can be maintained at a lower temperature, which is conducive to controlling the lowest temperature of the hot air input into the drying box 101. degree, so as to further expand the applicable temperature range of the hot air drying device 1 for PCB, and save the operating energy consumption of the heating box 103, thereby reducing the energy consumption of the hot air drying device 1 for PCB; when the intake volume of fresh air is small and the proportion of circulating air in the mixed air is large, the initial temperature of the mixed air is high, so that the mixed air output through the air outlet of the fan 102 and not heated by the heating box 103 has a higher temperature, which is beneficial to reduce the energy consumed by the heating box 103 when heating the mixed air, thereby achieving the effect of reducing the operating energy consumption of the hot air drying device 1 for PCB.

[0046] Optionally, the hot air drying device 1 for PCB also includes a second temperature probe 111, which is arranged in the drying chamber. The second temperature probe 111 is communicated with the first regulating valve 110 through the control mechanism 105. The second temperature probe 111 is used to monitor the temperature in the drying chamber and feed back to the control mechanism 105 to control the opening of the first regulating valve 110 through the control mechanism 105.

[0047] In this way, by setting the second temperature probe 111, the temperature of the hot air input into the drying chamber can be monitored to prevent the hot air heated by the heater 1032 from exceeding the working temperature and control the risk of heating and ignition, which is beneficial to improve the operation reliability of the hot air drying device 1 for PCB. At the same time, by monitoring the second temperature probe 111, the control mechanism 105 automatically adjusts the opening of the first regulating valve 110, which can reduce manual intervention and improve the flexibility and automation of the hot air drying device 1 for PCB. Optionally, considering that the hot air first passes through the first temperature probe 1033 and then to the second temperature probe 111, when the temperature of the hot air is greater than the preset high temperature value of the first temperature probe 1033, although the heater 1032 is turned off, the heated hot air is still continuously supplied to the drying chamber, causing the temperature of the drying chamber to continue to rise. Therefore, the temperature in the drying chamber has a hysteresis compared with the heating box 103. Based on this, the preset high temperature value of the first temperature probe 1033 is greater than the preset high temperature value of the second temperature probe 111, and the preset low temperature value of the first temperature probe 1033 is less than the preset low temperature value of the second temperature probe 111.

[0048] Exemplarily, when the real-time temperature detected by the first temperature probe 1033 is greater than the preset high temperature value, the control mechanism 105 controls the heater 1032 to shut down, and the temperature in the drying chamber continues to rise due to hysteresis. When the temperature in the drying chamber reaches the preset high temperature value of the second temperature probe 111, the opening of the first regulating valve 110 increases to increase the proportion of fresh air in the mixed air, and the initial temperature of the mixed air decreases. After the mixed air enters the drying chamber through the fan 102 and the heating box 103 in sequence, the temperature in the drying chamber gradually decreases. When the temperature in the drying chamber drops to less than the preset low temperature value of the second temperature probe 111, the control mechanism 105 controls the opening of the first regulating valve 110 to decrease to reduce the proportion of fresh air in the mixed air, and the initial temperature of the mixed air rises again. In this cycle, the operating temperature of the drying box 101 is maintained by controlling the opening of the first regulating valve 110.

[0049] In some embodiments, considering that when the temperature requirement of hot air used to dry PCBs is low, there is no need to turn on the heater 1032. The heat requirement of the drying chamber can be met only by superposition of the initial temperature after the fresh air and the circulating air are mixed with the operating heat inside the fan 102. At this time, the hot air drying device 1 for PCBs has lower energy consumption. Based on this, the hot air drying device 1 for PCBs also includes a second regulating valve 112. The second regulating valve 112 is arranged at one end of the three-way pipe 106 close to the second inlet 1062. The second regulating valve 112 is used to adjust the air intake of the second inlet 1062.

[0050] In this way, by setting the second regulating valve 112 for adjusting the air intake volume of the circulating air, the first regulating valve 110 and the second regulating valve 112 are used to cooperate to facilitate controlling the initial temperature of the mixed air, so that the hot air drying device 1 for PCB has a larger applicable temperature range while maintaining low energy consumption characteristics.

[0051] For example, when the hot air temperature requirement for drying PCBs is relatively high, and the condition that the temperature of the mixed air that is not heated by the heating box 103 is lower than the preset low temperature value of the second temperature probe 111 cannot be satisfied even when the first regulating valve 110 is adjusted to the minimum opening, the control mechanism 105 will start the heater 1032 in response to the signal fed back by the second temperature probe 111. At this time, in order to turn on the heater 1032, the opening of the second regulating valve 112 can be increased manually or by other means (such as remote control or command control, etc.) to increase the flow rate of the circulating air at the second inlet 1062, thereby increasing the proportion of the circulating air in the mixed air and raising the initial temperature of the mixed air, so that the hot air drying device 1 for PCBs can satisfy the condition that the temperature in the drying chamber is higher than the preset low temperature value of the second temperature probe 111 and the temperature in the drying chamber reaches the hot air temperature for drying PCBs when the heater 1032 is not turned on, through the superposition of the operating heat of the circulating air and the fan 102.

[0052] Optionally, the first temperature probe 1033 has a preset high alarm value, and the control mechanism 105 is also used to issue an alarm when the temperature in the heating box 103 monitored in real time by the first temperature probe 1033 reaches the preset high alarm value, so as to remind the operator that the temperature in the drying chamber is too high. At this time, the opening of the second regulating valve 112 can be reduced manually or by other means (such as remote control or command control, etc.) to reduce the flow rate of the circulating air at the second inlet 1062, thereby reducing the proportion of the circulating air in the mixed air, and reducing the initial temperature of the mixed air by mixing the fresh air and the circulating air, so as to reduce the temperature of the hot air input into the drying chamber, thereby satisfying that the temperature in the drying chamber is less than the preset high temperature value of the second temperature probe 111.

[0053] In some embodiments, the hot air drying device 1 for PCB also includes a wind knife 113 and a plate moving mechanism 114, the wind knife 113 and the plate moving mechanism 114 are located in the drying box 101, and the hot air filter 104 is installed between the hot air outlet and the hot air inlet, the hot air inlet is connected to the air inlet of the wind knife 113, and the air outlet of the wind knife 113 is arranged corresponding to the plate moving mechanism 114, and the plate moving mechanism 114 is used to convey the PCB.

[0054] In this way, by providing the wind knife 113 and the plate-moving mechanism 114, the wind knife 113 is used to output hot air during the process of conveying the PCB to wind-dry the PCB, thereby improving the drying efficiency. At the same time, the hot air filter 104 is provided between the wind knife 113 and the heating box 103, which can not only purify the airflow blowing toward the PCB and improve the product quality of the PCB, but also filter the hot air entering the wind knife 113 to avoid the situation where the particulate impurities or dust carried in the hot air block the wind knife 113, thereby improving the reliability of the hot air drying device 1 for PCB.

[0055] Optionally, the walking mechanism 114 includes a first roller group 1141, a second roller group 1142 and a driving part 1143, the driving part 1143 is used to drive the first roller group 1141 and the second roller group 1142 to rotate relative to each other, the first roller group 1141 and the second roller group 1142 are arranged at intervals to form a conveying space for accommodating PCBs, the first roller group 1141 includes a plurality of first rollers arranged in sequence and at intervals along its axial direction, the second roller includes a plurality of second rollers arranged in sequence and at intervals along its axial direction, the plurality of first rollers correspond one-to-one to the plurality of second rollers, and the air outlet of the wind knife 113 is arranged corresponding to the gap between two adjacent first rollers or two adjacent second rollers.

[0056] In this way, the PCB is driven to move by the relative rotation of the first roller and the second roller. During the process of conveying the PCB, the wind knife 113 blows toward the PCB surface through the gap between the two first rollers or the two second rollers. That is, during the process of conveying the PCB, the wind knife 113 is used to blow hot air to different positions of the PCB surface, thereby improving the drying efficiency of the PCB, ensuring the drying effect of the PCB, and further helping to improve the quality of the finished PCB product.

[0057] Optionally, the driving part 1143 includes a first rotating member 11431, a second rotating member 11432 and a support plate 11433, the support plate 11433 is provided with a slide groove, the first rotating member 11431 is connected to the first roller group 1141 through a first rotating shaft, the second rotating member 11432 is connected to the second roller group 1142 through a second rotating shaft, the first rotating shaft and the second rotating shaft are passed through the slide groove, so that the first rotating member 11431 and the first roller group 1141 are respectively arranged on both sides of the support plate 11433, the second rotating member 11432 and the second roller group 1142 are respectively arranged on both sides of the support plate 11433, and the first rotating shaft and the second rotating shaft are slidable along the extension direction of the first slide groove.

[0058] Taking the example of the first roller group 1141 being located on the side of the second roller group 1142 close to the ground, when the semi-finished PCB board enters the drying box 101, due to the hardness of the board itself, the supporting force of the first roller group 1141 and the forward momentum, the second roller group 1142 is propped up along the extension direction of the slide groove, and at the same time, the second roller group 1142 will provide a reaction force to the semi-finished board due to its own gravity, so that friction is generated between the second roller group 1142 and the upper surface of the semi-finished board, and at this time, the semi-finished board's own gravity plus the reaction force of the second roller group 1142 will generate a certain friction force on the first roller, so that when the first roller group 1141 rotates, the upper and lower surfaces of the semi-finished board are both subjected to the friction force to obtain the forward momentum, so that the semi-finished board can be transmitted under the action of the walking mechanism 114. At the same time, by setting the first rotating member 11431 and the second rotating member 11432, they can be rotated and connected after the semi-finished plate is taken out to reduce the friction when the first rotating member 11431 and the second rotating member 11432 collide with each other, so as to facilitate the relative rotation of the first roller group 1141 and the second roller group 1142.

[0059] Optionally, the first rotating member 11431 and the second rotating member 11432 are gears, and the modules and tooth angles of the two gears are equal, so that the first rotating member 11431 and the second rotating member 11432 can be meshed and connected after the semi-finished plate is taken out to improve the structural reliability of the driving part 1143, and it is also beneficial to the transmission of the first roller group 1141 and the second roller group 1142, so that the driving mechanism can drive the first roller group 1141 and the second roller group 1142 to rotate.

[0060] Optionally, the control mechanism 105 is connected to the first rotating member 11431 and the second rotating member 11432 respectively, and the control mechanism 105 controls the rotation of the first rotating member 11431 and the second rotating member 11432 to realize the transmission of the PCB in the drying chamber.

[0061] It can be understood that in other embodiments, the first rotating member 11431 and the second rotating member 11432 can also be a rotating shaft or a prism.

[0062] Optionally, the number of wind knives 113 can be two groups, and the two groups of wind knives 113 are respectively connected to the outlet of the hot air filter 104, and the air outlet of one group of wind knives 113 corresponds to the first roller group 1141, and the air outlet of the other group of wind knives 113 corresponds to the second roller group 1142, so that hot air can be supplied to the upper and lower surfaces of the semi-finished board at the same time, so as to improve the drying efficiency and drying effect of the semi-finished board, which is beneficial to improve the quality of the finished PCB.

[0063] Optionally, the number of each group of wind knives 113 may be one or more, which can be set according to actual needs and is not limited here.

[0064] The embodiments of the present application are described in detail above in conjunction with the accompanying drawings, but the present application is not limited to the above embodiments. Various changes can be made within the knowledge scope of ordinary technicians in the technical field without departing from the purpose of the present application.

Claims

1. A hot air drying device for PCB, characterized in that: include: A drying box, wherein the drying box is provided with a drying chamber, a hot air inlet and a circulating air outlet, the drying chamber is used to dry the PCB, the hot air inlet and the circulating air outlet are arranged at intervals and are respectively connected to the drying chamber; A fan, wherein the fan is connected to a three-way pipe, the three-way pipe has a first inlet, a second inlet and a first outlet, the first inlet is used to introduce fresh air, the second inlet is connected to the circulating air outlet, and the first outlet is connected to the air inlet of the fan; A heating box, the heating box comprising a box body, a heater and a first temperature probe arranged in the box body, the air inlet of the box body being connected to the air outlet of the fan, the box body being provided with a hot air outlet, the hot air outlet being connected to the hot air inlet, the first temperature probe being used to monitor the temperature in the box body and feedback control the start and stop of the heater; and A hot air filter is arranged on the path of hot air from the hot air outlet to the PCB.

2. The hot air drying device for PCB according to claim 1, characterized in that: The hot air drying device for PCB further includes a first regulating valve, which is arranged at one end of the three-way pipe close to the first inlet, and the first regulating valve is used to adjust the air intake volume of the first inlet.

3. The hot air drying device for PCB according to claim 2, characterized in that: The hot air drying device for PCB also includes a second temperature probe, which is arranged in the drying chamber. The second temperature probe is communicatively connected with the first regulating valve, and the second temperature probe is used to monitor the temperature in the drying chamber and feedback control the opening of the first regulating valve.

4. The hot air drying device for PCB according to claim 2, characterized in that: The hot air drying device for PCB further comprises a second regulating valve, which is arranged at one end of the three-way pipe close to the second inlet, and the second regulating valve is used to adjust the air intake volume of the second inlet.

5. The hot air drying device for PCB according to claim 1, characterized in that: The hot air drying device for PCB also includes an air knife and a plate-moving mechanism, the air knife and the plate-moving mechanism are located in the drying box, and the hot air filter is installed between the hot air outlet and the hot air inlet, the hot air inlet is connected to the air inlet of the air knife, and the air outlet of the air knife is arranged corresponding to the plate-moving mechanism, and the plate-moving mechanism is used to convey the PCB.

6. The hot air drying device for PCB according to claim 5, characterized in that: The plate walking mechanism includes a first roller group, a second roller group and a driving part, the driving part is used to drive the first roller group and the second roller group to rotate relative to each other, the first roller group and the second roller group are arranged at intervals to form a conveying space for accommodating PCBs, the first roller group includes a plurality of first rollers arranged in sequence and at intervals along its axial direction, the second roller includes a plurality of second rollers arranged in sequence and at intervals along its axial direction, the plurality of first rollers correspond to the plurality of second rollers one by one, and the air outlet of the wind knife is arranged corresponding to the gap between two adjacent first rollers or two adjacent second rollers.

7. The hot air drying device for PCB according to claim 6, characterized in that: The driving part includes a first rotating member, a second rotating member and a supporting plate, the supporting plate is provided with a slide groove, the first rotating member is connected to the first roller group through a first rotating shaft, the second rotating member is connected to the second roller group through a second rotating shaft, the first rotating shaft and the second rotating shaft are passed through the slide groove, so that the first rotating member and the first roller group are respectively arranged on both sides of the supporting plate, the second rotating member and the second roller group are respectively arranged on both sides of the supporting plate, and the first rotating shaft and the second rotating shaft are slidable along the extension direction of the slide groove.

8. The hot air drying device for PCB according to any one of claims 1 to 7, characterized in that: The hot air drying device for PCB also includes a wind pressure gauge, which is installed on the hot air filter and is communicatively connected to the fan, and is used to monitor and adjust the wind pressure at the air outlet of the fan.

9. The hot air drying device for PCB according to any one of claims 1 to 7, characterized in that: The hot air drying device for PCB further comprises a fresh air filter, and an outlet of the fresh air filter is connected to the first inlet.

10. The hot air drying device for PCB according to any one of claims 1 to 7, characterized in that: The drying box is also provided with an exhaust gas discharge port connected to the drying chamber, and the exhaust gas discharge port is used to connect to an exhaust system to discharge the exhaust gas in the drying chamber.

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