Formic acid supply system and vacuum reflow soldering furnace thereof

Abstract

The utility model discloses a formic acid supply system and a vacuum reflow soldering furnace thereof, and the formic acid supply system comprises a formic acid conveying pipeline which comprises an acid storage bottle and a formic acid tower which are sequentially communicated through a pipeline, and formic acid stored in the acid storage bottle can be conveyed into the formic acid tower through a pump arranged on the pipeline; the gas conveying pipeline comprises a nitrogen supply assembly, a pressure regulating valve and a first manual stop valve which are communicated in sequence, the nitrogen supply assembly is communicated to the formic acid tower through a pipeline, and the formic acid tower is communicated with the furnace body cavity and can introduce formic acid gas into the furnace body cavity; wherein the number of the formic acid towers is at least one, each formic acid tower is correspondingly communicated with one furnace body chamber, and each formic acid tower is communicated to the same acid washing bottle. The acid washing bottle and the acid storage bottle are placed in the anti-explosion box, the anti-explosion box can avoid formic acid leakage and splashing caused by breakage of the acid washing bottle and the acid storage bottle or damage of pipelines and the like, the opportunity of contact with formic acid in manual operation is reduced, and damage caused by formic acid leakage is prevented.

Description

Technical Field

[0001] This utility model belongs to the field of vacuum reflow oven technology, specifically relating to a formic acid supply system and its vacuum reflow oven. Background Technology

[0002] Formic acid is a colorless liquid with the chemical formula HCOOH. It is a common organic acid with a strong, pungent odor. In chemical reactions, formic acid is commonly used as a solvent, preservative, reducing agent, and catalyst.

[0003] Formic acid also plays a crucial role in vacuum reflow soldering technology for electronic products. It effectively removes bubbles and gases generated during soldering, ensuring solder joint quality. Furthermore, its high boiling point prevents solder joints from flowing at high temperatures, thus preventing solder joint collisions and short circuits, and improving the stability and reliability of electronic products. Formic acid also prevents components from being oxidized and corroded, extending their lifespan.

[0004] Formic acid is an acidic substance. When using formic acid, strict adherence to safety operating procedures and wearing appropriate protective equipment are essential to avoid direct contact with skin and eyes, preventing burns and poisoning. This invention reduces the chance of manual contact with formic acid and prevents injuries caused by formic acid leaks. It also allows for centralized supply and distribution to multiple reflow oven chambers and can be expanded into a centralized supply and distribution system for multiple reflow ovens. Utility Model Content

[0005] To address the aforementioned problems in the existing technology, this utility model provides a formic acid supply system and its vacuum reflow oven, including a formic acid delivery pipeline and a gas delivery pipeline. The acid washing bottle and the acid storage bottle are placed in an explosion-proof box. The explosion-proof box can prevent formic acid leakage and splashing caused by the breakage of the acid washing bottle and the acid storage bottle or damage to the pipeline. This utility model reduces the chance of manual contact with formic acid and prevents injury caused by formic acid leakage.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] A formic acid supply system, comprising:

[0008] Formic acid delivery pipeline, which includes an acid storage bottle and a formic acid tower connected in sequence through the pipeline, wherein the formic acid stored in the acid storage bottle can be delivered to the formic acid tower by a pump installed on the pipeline;

[0009] A gas delivery pipeline includes a nitrogen supply component, a pressure regulating valve, and a first manual shut-off valve connected in sequence. The nitrogen supply component is connected to the formic acid tower through the pipeline. The formic acid tower is connected to the furnace chamber and can introduce formic acid gas into the furnace chamber.

[0010] The number of formic acid towers is set to at least one, each formic acid tower is connected to a corresponding furnace chamber, and each formic acid tower is connected to the same acid washing bottle.

[0011] Furthermore, the pump, acid washing bottle, and acid storage bottle are all housed in an explosion-proof enclosure. A third liquid level sensor is installed on the side of the explosion-proof enclosure to monitor the liquid level in the acid storage bottle.

[0012] Furthermore, the gas delivery pipeline also includes a second manual shut-off valve, which is provided for each formic acid tower and is located downstream of the pressure regulating valve.

[0013] Furthermore, a first solenoid valve, a flow meter, and a third solenoid valve are also installed on the pipeline connecting the nitrogen supply component and the formic acid tower. The first solenoid valve and the third solenoid valve are respectively installed on both sides of the flow meter, and the first solenoid valve is located downstream of the second manual shut-off valve.

[0014] Furthermore, a second solenoid valve is provided between the formic acid tower and the furnace chamber.

[0015] Furthermore, a fourth solenoid valve is provided between each of the formic acid towers and the acid washing bottles.

[0016] Furthermore, a third manual shut-off valve, a fifth solenoid valve, and a check valve are provided between the formic acid tower and the acid storage bottle. The check valve is connected to the acid storage bottle, and the third manual shut-off valve is located between the fifth solenoid valve and the check valve.

[0017] Furthermore, a one-way filter is installed on the acid storage bottle, and the one-way filter is connected to the atmosphere.

[0018] Furthermore, a first liquid level sensor and a second liquid level sensor are installed on the side of the formic acid tower, with the first liquid level sensor located above the second liquid level sensor.

[0019] In addition, this utility model also claims protection for a vacuum reflow oven equipped with a formic acid supply system as described in any one of the above claims.

[0020] Compared with existing technologies, the beneficial effects of this solution are:

[0021] Formic acid is an acidic substance, and direct contact with skin and eyes can easily cause burns and poisoning. This invention provides a formic acid supply system and its vacuum reflow oven, including formic acid delivery pipelines and gas delivery pipelines. The acid washing bottle and acid storage bottle are placed in an explosion-proof box. The explosion-proof box prevents formic acid leakage and splashing due to breakage of the acid washing bottle and storage bottle or damage to the pipelines. This invention reduces the chance of manual contact with formic acid and prevents injuries caused by formic acid leakage.

[0022] The formic acid tower and furnace chamber are each equipped with several corresponding units. Nitrogen is used as a carrier to fill the formic acid tower. The formic acid liquid is volatilized into gas and released into the furnace chamber for process operation. The nitrogen supply unit can simultaneously supply and distribute to multiple furnace chambers, and can also be expanded to centrally supply and distribute to multiple reflow ovens. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the formic acid supply system;

[0024] Figure 2 This is a schematic diagram of the explosion-proof box structure;

[0025] Figure 3 This is a cross-sectional view of the formic acid tower.

[0026] Figure 4 for Figure 3 AA sectional view.

[0027] The reference numerals in the attached figures are as follows:

[0028] Explosion-proof box 1, acid storage bottle 11, one-way filter 111, pump 12, acid washing bottle 13, exhaust pipe 131, third liquid level sensor 14, first solenoid valve 15, flow meter 16, third solenoid valve 17, fourth solenoid valve 18, formic acid tower 2, pressure regulating valve 21, first manual shut-off valve 22, second manual shut-off valve 23, third manual shut-off valve 24, fifth solenoid valve 25, check valve 26, first liquid level sensor 27, second liquid level sensor 28, furnace chamber 3, second solenoid valve 31, base 32, glass jar 33, top cover 34, explosion-proof baffle 35, air inlet pipe 36, air outlet pipe 37, vent pipe 38, acid inlet pipe 39. Detailed Implementation

[0029] The present invention will now be described in further detail with reference to the accompanying drawings.

[0030] A formic acid supply system, such as Figure 1 As shown, it includes:

[0031] Formic acid delivery pipeline, which includes an acid storage bottle 11 and a formic acid tower 2 connected in sequence by the pipeline, wherein the formic acid stored in the acid storage bottle 11 can be delivered to the formic acid tower 2 by a pump 12 installed on the pipeline;

[0032] The gas delivery pipeline includes a nitrogen supply component, a pressure regulating valve 21 and a first manual shut-off valve 22 connected in sequence. The nitrogen supply component is connected to the formic acid tower 2 through the pipeline. The formic acid tower 2 is connected to the furnace chamber 3 and can introduce formic acid gas into the furnace chamber 3.

[0033] The number of formic acid towers 2 is set to at least one, each formic acid tower 2 is connected to a corresponding furnace chamber 3, and each formic acid tower 2 is connected to the same acid washing bottle 13.

[0034] According to a specific embodiment of this utility model, the acid storage bottle 11 is a large-capacity glass bottle for storing formic acid. Its volume is calculated based on the actual formic acid demand during production, and it can simultaneously meet the formic acid usage of multiple furnace chambers 3 within a certain time period, reducing the frequency of manual formic acid replenishment. In existing formic acid supply systems, when formic acid runs out, it is generally necessary to manually add formic acid to the formic acid bottle. This utility model allows for complete bottle replacement, reducing damage caused by formic acid leakage during pouring. The function of the acid washing bottle 13 is that when pump 12 draws formic acid into the formic acid tower 2, the air and formic acid volatile gases inside the formic acid tower 2 are gradually discharged. At this time, these mixed gases enter the acid washing glass bottle through a pipe. The acid washing bottle 13 contains a neutralizing liquid, which neutralizes these mixed gases into harmless gases before discharge.

[0035] In this embodiment, the nitrogen supply component can use industrial gas cylinders for gas delivery. Four formic acid towers 2 and four furnace chambers 3 are correspondingly provided. The nitrogen supply component is connected to several branch pipelines of the formic acid towers 2 via a main pipeline, using nitrogen as a carrier to fill the formic acid towers 2. The formic acid towers 2 then evaporate the liquid formic acid into gas and release it into the furnace chambers 3 for process operation. The formic acid towers 2 serve as temporary storage containers for formic acid, such as... Figure 3 and Figure 4 As shown, the formic acid tower 2 includes a base 32, a glass jar 33 fixed on the upper part of the base 32, a sealed top cover 34 on the upper part of the glass jar 33, and an explosion-proof baffle 35 surrounding the glass jar 33 and installed on the base 32. The top cover 34 is connected to an inlet pipe 36, which is connected to a nitrogen supply component. The top cover 34 is also connected to an outlet pipe 37, which is connected to a corresponding furnace chamber 3. The top cover 34 is further connected to a vent pipe 38, which is connected to an acid washing bottle 13. The acid washing bottle 13 is connected to the atmosphere through an exhaust pipe 131. The top cover 34 is also connected to an acid inlet pipe 39, which is connected to an acid storage bottle 11.

[0036] Each furnace chamber 3 is equipped with a formic acid tower 2 to facilitate control of the required amount of nitrogen during production in each furnace chamber 3. The pressure regulating valve 21 is used to adjust the nitrogen pressure to a suitable level, preventing damage to components or leaks in the piping due to excessive pressure. The first manual shut-off valve 22 is the main nitrogen valve; it is normally open during equipment operation. If the equipment requires overall maintenance, this first manual shut-off valve 22 is closed to avoid affecting the operation of other equipment.

[0037] Furthermore, the pump 12, the acid washing bottle 13, and the acid storage bottle 11 are all housed within an explosion-proof enclosure 1, such as... Figure 2As shown, a third liquid level sensor 14 is installed on the side of the explosion-proof box 1. The third liquid level sensor 14 is used to monitor the liquid level height of the acid storage bottle 11.

[0038] The third liquid level sensor 14 is installed on the side of the acid storage bottle 11 at a height determined according to actual conditions. The acid washing bottle 13 and the acid storage bottle 11 are made of glass and are placed inside the explosion-proof box 1. The explosion-proof box 1 is used to protect against formic acid leakage and splashing caused by breakage of the acid washing bottle 13 and the acid storage bottle 11 or damage to pipelines. The explosion-proof box 1 is made of corrosion-resistant materials, such as stainless steel or plastic. The pump 12 also needs to be made of a material with good corrosion resistance and is installed inside the explosion-proof box 1. The installation position of the pump 12 can be determined according to the installation requirements of different types of pumps. In this embodiment, the pump 12 is a peristaltic pump, so it is installed on the upper part of the inner wall of the explosion-proof box 1. The third liquid level sensor 14 is used to detect the remaining formic acid in the acid storage bottle 11. If the formic acid level is lower than the set level, it will automatically prompt for replacement.

[0039] Furthermore, the gas delivery pipeline also includes a second manual shut-off valve 23. The second manual shut-off valve 23 is installed on each branch pipeline of the formic acid tower 2, corresponding to each formic acid tower 2, and is located downstream of the pressure regulating valve 21. The second manual shut-off valve 23 is a nitrogen branch valve. During equipment use, the second manual shut-off valve 23 is normally open. If the corresponding furnace chamber 3 requires maintenance, the second manual shut-off valve 23 is closed to avoid affecting the use of other furnace chambers 3.

[0040] Furthermore, a first solenoid valve 15, a flow meter 16, and a third solenoid valve 17 are also installed on the pipeline connecting the nitrogen supply component and the formic acid tower 2. The first solenoid valve 15 and the third solenoid valve 17 are respectively installed on both sides of the flow meter 16. The first solenoid valve 15 is located downstream of the second manual shut-off valve 23. The flow meter 16 is also called a mass flow meter (MFC), which is a precise and stable device for measuring and controlling the mass flow rate of fluids. The flow meter 16 is used to accurately control the amount required for each furnace chamber 3 during process production.

[0041] Furthermore, a second solenoid valve 31 is provided between the formic acid tower 2 and the furnace chamber 3.

[0042] Furthermore, a fourth solenoid valve 18 is provided between each of the formic acid towers 2 and the acid washing bottles 13.

[0043] The first manual shut-off valve 22, the second manual shut-off valve 23, the flow meter 16, the first solenoid valve 15, and the second solenoid valve 31 are installed on each branch pipeline of the formic acid tower 2. The first solenoid valve 15, the second solenoid valve 31, and the third solenoid valve 17 are opened simultaneously according to the product processing requirements in the corresponding furnace chamber 3, thus ensuring the supply of formic acid to the corresponding furnace chamber 3. The branch pipeline of the formic acid tower 2 corresponding to the first solenoid valve 15 is used for nitrogen gas control. Because the flow meter 16 (MFC) is a precision instrument, shutting off the first solenoid valve 15 when not in use can prevent nitrogen pressure overshoot or damage from prolonged pressure. The second solenoid valve 31 is used for nitrogen gas control; it can be shut off when not in use to prevent formic acid in the formic acid tower 2 from entering the corresponding furnace chamber 3 due to natural evaporation. The third solenoid valve 17 is used for nitrogen opening and closing. When not in use, the third solenoid valve 17 can be shut off to prevent formic acid in formic acid tower 2 from entering and damaging the flow meter 16 due to natural evaporation.

[0044] Furthermore, a third manual shut-off valve 24, a fifth solenoid valve 25, and a check valve 26 are provided between the formic acid tower 2 and the acid storage bottle 11. The check valve 26 is connected to the acid storage bottle 11, and the third manual shut-off valve 24 is located between the fifth solenoid valve 25 and the check valve 26.

[0045] Furthermore, a first liquid level sensor 27 and a second liquid level sensor 28 are installed on the side of the formic acid tower 2, with the first liquid level sensor 27 located above the second liquid level sensor 28. The first liquid level sensor 27 and the second liquid level sensor 28 are mounted on the explosion-proof baffle 35.

[0046] When the fourth solenoid valve 18 and the fifth solenoid valve 25 detect that the formic acid liquid level in a formic acid tower 2 is lower than the set level (second level sensor 28), they simultaneously open the fourth solenoid valve 18, the fifth solenoid valve 25, and the pump 12 to pump the formic acid from the storage bottle 11 into the formic acid tower 2. When the first level sensor 27 detects the liquid level, the fourth solenoid valve 18, the fifth solenoid valve 25, and the pump 12 simultaneously close, indicating that the formic acid tower 2 is full. The system cannot operate when the nitrogen supply line is in operation, i.e., when the first solenoid valve 15, the second solenoid valve 31, and the third solenoid valve 17 are open.

[0047] The fourth solenoid valve 18, the fifth solenoid valve 25, and the pump 12 prevent excessive formic acid gas from entering the furnace chamber 3.

[0048] Furthermore, a one-way filter 111 is installed on the acid storage bottle 11, and the one-way filter 111 is open to the atmosphere. The one-way filter 111 is open to the atmosphere to prevent a vacuum inside the acid storage bottle 11 caused by the pump 12 when pumping formic acid.

[0049] In addition, this utility model also claims protection for a vacuum reflow oven equipped with a formic acid supply system as described in any one of the above claims.

[0050] Finally, it should be noted that in the description of this utility model, the terms "vertical," "upper," "lower," "horizontal," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0051] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0052] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A formic acid supply system, characterized in that, include: Formic acid delivery pipeline, which includes an acid storage bottle and a formic acid tower connected in sequence through the pipeline, wherein the formic acid stored in the acid storage bottle can be delivered to the formic acid tower by a pump installed on the pipeline; A gas delivery pipeline includes a nitrogen supply component, a pressure regulating valve, and a first manual shut-off valve connected in sequence. The nitrogen supply component is connected to the formic acid tower through the pipeline. The formic acid tower is connected to the furnace chamber and can introduce formic acid gas into the furnace chamber. The number of formic acid towers is set to at least one, each formic acid tower is connected to a corresponding furnace chamber, and each formic acid tower is connected to the same acid washing bottle.

2. The formic acid supply system according to claim 1, characterized in that: The pump, acid washing bottle, and acid storage bottle are all housed in an explosion-proof box. A third liquid level sensor is installed on the side of the explosion-proof box to monitor the liquid level in the acid storage bottle.

3. The formic acid supply system according to claim 2, characterized in that: The gas delivery pipeline also includes a second manual shut-off valve, which is provided for each formic acid tower and is located downstream of the pressure regulating valve.

4. The formic acid supply system according to claim 3, characterized in that: The pipeline connecting the nitrogen supply component and the formic acid tower is also equipped with a first solenoid valve, a flow meter, and a third solenoid valve. The first solenoid valve and the third solenoid valve are respectively installed on both sides of the flow meter, and the first solenoid valve is located downstream of the second manual shut-off valve.

5. A formic acid supply system according to any one of claims 1-4, characterized in that: A second solenoid valve is installed between the formic acid tower and the furnace chamber.

6. A formic acid supply system according to any one of claims 1-4, characterized in that: A fourth solenoid valve is installed between each of the formic acid towers and the acid washing bottles.

7. A formic acid supply system according to claim 6, characterized in that: A third manual shut-off valve, a fifth solenoid valve, and a check valve are provided between the formic acid tower and the acid storage bottle. The check valve is connected to the acid storage bottle, and the third manual shut-off valve is located between the fifth solenoid valve and the check valve.

8. A formic acid supply system according to claim 7, characterized in that: The acid storage bottle is equipped with a one-way filter, which is connected to the atmosphere.

9. A formic acid supply system according to claim 8, characterized in that: A first liquid level sensor and a second liquid level sensor are installed on the side of the formic acid tower, with the first liquid level sensor located above the second liquid level sensor.

10. A vacuum reflow oven, characterized in that: The system is equipped with a formic acid supply system as described in any one of claims 1-9.

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