CN202485380U - PCB (Printed Circuit Board) production line and drying device of PCB production line - Google Patents

Abstract

The utility model provides a drying device of a PCB production line. The drying device comprises a hot air source, a plurality of air knives, a hot air pipe and an air return pipe; the plurality of air knives are distributed in a drying section of the PCB production line; the hot air pipe communicates the hot air source and the air knives; and the air return pipe communicate the drying section and the hot air source. In the embodiment of the utility model, the PCB production line is provided, and the drying section of the PCB production line is provided with the drying device. According to the PCB production line and the drying device of the PCB production line, the problem of heat energy waste in the prior art is solved and the energy-saving effect is achieved.

Description

Printed circuit board production line and its drying device

technical field

The utility model relates to the field of printed circuit boards (PCB), in particular to a PCB production line and a drying device thereof.

Background technique

In the process of manufacturing printed circuit boards, many wet manufacturing processes are involved, such as line etching, surface roughening, browning/blackening, etc. After these treatments, the boards need to be dried in time. Therefore, this kind of production equipment is equipped with a drying section. The function of the drying section is to dry the board surface and prevent the board surface from oxidation.

FIG. 1 shows a schematic diagram of a drying device of a PCB production line according to the prior art. The drying device is composed of an air knife 10 , a hot air source 20 and a hot air duct 30 . Wherein, the hot air source 20 is composed of a heater box 22, an exhaust pipe 24 and a blower 26, and a filter device 30 is also arranged in the hot air pipe, and an air outlet 40 is also opened on the groove wall of the drying section of the PCB production line. The blower 26 extracts the cool wind through the exhaust pipe 24, and the heating wire in the heater box 22 sends the cool wind to the filter unit 30 after being heated, and the filtered hot wind is sent to the drying section through the air knife 10. The PCB is conveyed forward in the drying section of the board, and a plurality of air knives 10 in the figure are arranged in pairs (the two on the left, the two on the middle and the two on the right in the figure form three pairs of air knives respectively), each One of the air knives 10 is on the top, and the other is on the bottom. The PCB is passing through the pair of air knives 10, and the hot air is blown to the board surface of the PCB to be dried. The hot air after drying is exhausted to the outside through the air outlet 40, thus causing a lot of waste of heat energy.

Utility model content

The utility model aims to provide a PCB production line and its drying device to achieve the purpose of energy saving.

In an embodiment of the present invention, a drying device for a PCB production line is provided, including: a hot air source; a plurality of air knives distributed in the drying section of the PCB production line; Knife; air return pipe, connecting the drying section and the hot air source.

In an embodiment of the present invention, a PCB production line is provided, the drying section of which is equipped with the above-mentioned drying device.

The PCB production line and its drying device in the above embodiments of the present invention overcome the problem of waste of heat energy in the prior art because the return air pipe is used to recycle the hot air, and the effect of energy saving is achieved.

Description of drawings

The drawings described here are used to provide a further understanding of the utility model and constitute a part of the application. The schematic embodiments of the utility model and their descriptions are used to explain the utility model and do not constitute improper limitations to the utility model. In the attached picture:

Fig. 1 shows the schematic diagram according to the drying device of the PCB production line of prior art;

Fig. 2 shows the schematic diagram of the drying device of the PCB production line according to the embodiment of the present invention;

Fig. 3 shows the schematic diagram of the drying device of the PCB production line according to another embodiment of the present invention;

Fig. 4 shows a schematic diagram of a cooling section according to an embodiment of the present invention;

Fig. 5 shows a schematic diagram of the setting process of the cooling section according to an embodiment of the present invention;

Fig. 6 shows a schematic diagram of air knife communication according to an embodiment of the present invention;

Fig. 7 shows a schematic diagram of a drying device of a PCB production line according to another embodiment of the present invention.

Detailed ways

The utility model will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

Fig. 2 shows a schematic diagram of a drying device of a PCB production line according to an embodiment of the present invention, including:

Hot air source 20;

A plurality of air knives 10 are distributed in the drying section of the PCB production line;

The hot air pipe 50 communicates with the hot air source and each air knife;

The air return pipe 60 communicates with the drying section and the hot air source 20 .

In the prior art of Fig. 1, the hot air in the drying section is directly discharged from the air outlet 40 of the drying section, but in this embodiment, the return air pipe is used to connect the drying section and the hot air source, so the hot air in the drying section It can be returned to the heat source through the air return pipe, thereby realizing the recycling of hot air, thereby overcoming the problem of waste of heat energy in the prior art, and achieving the effect of energy saving.

Preferably, the hot air source 20 includes:

The heating device 22, the hot air pipe 50 communicates with its air outlet;

Blower 26, the air inlet of its air outlet circulation heating device 22;

The exhaust pipe 24 is connected with the air inlet of the outdoor and the air blower 26;

Wherein, the air return pipe 60 is connected from the air inlet 40 of the drying section to the air inlet of the blower 26 .

In this embodiment, while the blower absorbs the circulating hot air from the return air duct, it also supplements the cool air from the outside through the exhaust duct, so as to ensure sufficient air volume and ensure the formation of positive pressure on the return air duct in the drying section. . The diameter of the exhaust pipe should be smaller than the diameter of the return air pipe, so that the air supply of the return air pipe is the main source. For example, the diameter of the exhaust pipe is 1/4 of the diameter of the return air pipe to ensure high utilization of the hot return air. In addition, the return air pipe is directly connected to the air outlet of the drying section, which can reduce the leakage of hot air in the drying section and further improve the utilization efficiency of heat energy. In addition, the blower can choose a high-volume low-pressure high-temperature blower. Because the air blower of the present embodiment sucks in hot air, so the air blower selects the high temperature resistant type.

FIG. 3 shows a schematic diagram of a drying device of a PCB production line according to another embodiment of the present invention, and the return air duct 60 includes a cooling section 70 . In the process of drying PCB boards, a large amount of water evaporates into the hot air, so that the circulating hot air has greater humidity. In this embodiment, a cooling section is added in the return air pipe, so that the water vapor in the return air can be condensed, thereby reducing the humidity of the circulating hot air. The dry hot air can better dry the PCB in process, so this embodiment can ensure the drying effect while improving the utilization efficiency of heat energy.

Fig. 4 shows the schematic diagram of the cooling section according to the embodiment of the present utility model, and the cooling section 70 comprises: one or more section coil pipes 72, which are in the ventilation path of the return air pipe 60; thin tubes 74, whose water inlet ends communicate with the coil pipes 72 The curved bottom of the curved bottom, its water outlet communicates with the external container 76. This structure utilizes the principle of the radiator, which is relatively simple and easy to implement. In addition, in this embodiment, thin tubes are added to communicate with the coils, which are specially used for drainage, so that the circulation of the hot air is not affected, and the condensed water can be effectively discharged.

Preferably, a valve 78 is provided at the outlet end of the thin tube 74 . By setting the valve, the thin tube can be closed when the water is not drained, thereby reducing the leakage of medium hot air and further improving the efficiency of heat energy utilization.

Preferably, tubule 74 is transparent. The thin tube uses a transparent pipe to observe the liquid level of the condensed water. When the liquid level is low, the valve is closed. Only when the water in the thin tube is almost full, the valve is opened to allow water to flow into the container.

Preferably, the length and diameter of the coil are set so that after the return air in the return air pipe flows through the coil, the temperature of the return air decreases greater than a threshold. One or more cooling sections can be set on the return air duct according to the requirements of different line drying panels to separate the moisture in the hot air, and improve the thermal cycle utilization rate as much as possible under the premise of achieving the drying effect. Taking the acid etching line as an example, the maximum board size of this PCB production line is 24*30inch, so the largest size board (24×30) is selected as the drying test object. Fig. 5 shows a schematic diagram of the setting process of the cooling section according to the embodiment of the present invention. The diameter of the cooling pipe is 50mm, the effective length of the cooling section is 2000mm, and the coiled length of one cooling section is 500mm. A thermometer is installed before the cooling section, and the measured temperature is 75°C. Use 1 section of natural cooling, install a thermometer after the cooling section, and measure the temperature at 65°C. In this case, observe the board surface after drying, and the drying is not sufficient. It shows that the water content of the hot air at this temperature is too high, and the water separation is insufficient, which cannot meet the drying requirements. Use 2 sections of natural cooling, install a thermometer after the cooling section, and measure the temperature at 55°C. In this case, observe the board surface after drying, and the board surface is fully dried. So choose to use 2 sections of natural cooling.

Preferably, part of the air knife communicates with the hot air pipe from one side, and another part of the air knife communicates with the hot air pipe from the other side. If the hot air pipes are connected from one end of the air knife, the temperature in the airtight air box (that is, the drying section) will be slightly higher at one end and slightly lower at the other end. Fig. 6 shows a schematic diagram of the communication of air knives according to an embodiment of the present invention. In this embodiment, the access ends of two adjacent groups of air knives 10 are different. It is that the hot air pipe 50 is sent in from the other end of the air knife 10 interspersedly.

Fig. 7 shows a schematic diagram of a drying device of a PCB production line according to another embodiment of the present invention. The outer surfaces of the hot air pipe 50 and the return air pipe 60 are wrapped with thermal insulation materials, and the air filter device 30 is arranged in the hot air pipe 50 . Wind insulation cotton on the hot air pipe and the return air pipe to reduce the heat loss of the hot air and achieve better recycling of heat energy. Setting up an air filter device can improve the cleanliness of the air, thereby preventing the PCB from being polluted on the surface of the board.

An embodiment of the present invention provides a PCB production line, the drying section of which is equipped with the above-mentioned drying device.

It can be seen from the above description that in the above embodiments of the utility model, a return air duct is added to recycle hot air, reducing heat loss.

The above descriptions are only preferred embodiments of the utility model, and are not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present utility model shall be included in the protection scope of the present utility model.

Claims (10)

1. the drying unit of a PCB production line is characterized in that, comprising:

Hot air source;

A plurality of air knives are distributed in the oven dry section of said PCB production line;

Warm-air pipe is communicated with said hot air source and each said air knife;

Backwind tube is communicated with said oven dry section and said hot air source.

2. device according to claim 1 is characterized in that, said hot air source comprises:

Heater, said warm-air pipe is communicated with its air outlet;

The circulate air intake vent of said heater of air blast, its air outlet;

Exhaust column is communicated with air intake vent outdoor and said air blast;

Wherein, said backwind tube is communicated to the air intake vent of said air blast from the suction opeing of said oven dry section.

3. device according to claim 1 is characterized in that, comprises cooling section in the said backwind tube.

4. device according to claim 3 is characterized in that, said cooling section comprises:

One or more snippets coil pipe is in the ventilating path of said backwind tube;

Tubule, its water intake end is communicated with the curved bottom of said coil pipe, and its water side is communicated with outside container.

5. device according to claim 4 is characterized in that, is provided with valve in the water side of said tubule.

6. device according to claim 5 is characterized in that said tubule is transparent.

7. device according to claim 4 is characterized in that, the length of said coil pipe and diameter are configured such that return in the said backwind tube behind said coil pipe, and the temperature of said return air reduces greater than threshold value.

8. device according to claim 1 is characterized in that the part air knife is communicated with said warm-air pipe from a side, and another part air knife is communicated with said warm-air pipe from opposite side.

9. device according to claim 1 is characterized in that, the coated outside insulation material of said warm-air pipe and said backwind tube is provided with air filter in the said warm-air pipe.

10. a PCB production line is characterized in that, its oven dry section is installed according to each described drying unit of claim 1-9.

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