Vacuum reflow soldering furnace

Abstract

The utility model discloses a vacuum reflow soldering furnace, which comprises a furnace body cavity, a furnace body cavity, a furnace body cover, a furnace body cover, a furnace body cover, a furnace body cover, a furnace body cover and a furnace body cover, the backflow cover is arranged in the cavity upper cover, one side of the backflow cover is opened, and the opening of the backflow cover is deviated from the inner wall of the cavity upper cover; the backflow box is arranged in the cavity upper cover, the backflow box is matched with the backflow cover in shape, the backflow box is fixed at the opening of the backflow cover, the backflow box is provided with a backflow groove, and the backflow groove wraps the edge of the opening of the backflow cover by a circle. After the chamber upper cover of the furnace body chamber is covered on the lower chamber, soldering flux is gasified due to heating and then volatilized into mist to suspend in the furnace body chamber, the outer wall of the backflow cover is contacted with the chamber upper cover, and when the cooled outer wall of the backflow cover is encountered, the soldering flux can be attached to the inner wall of the backflow cover to be condensed into liquid, so that the soldering flux is cooled. When a large amount of scaling powder is attached, the scaling powder can flow downwards along the inner wall of the backflow cover under the action of gravity until the scaling powder flows into the U-shaped backflow box, and the backflow cover and the backflow box are matched so that the scaling powder can be prevented from flowing into the lower cavity of the furnace body cavity.

Description

Technical Field

[0001] This utility model belongs to the field of vacuum reflow oven technology, and specifically relates to a vacuum reflow oven. Background Technology

[0002] Vacuum reflow ovens are specialized equipment used for high-quality soldering of semiconductor chips in a vacuum environment, widely applied in precision soldering processes for high-end electronic components. During reflow soldering, solder paste or solder pads are the primary soldering materials, and their characteristics directly affect the soldering effect. Compared to solder paste, solder pads have the advantages of requiring no flux, requiring no post-soldering cleaning, and exhibiting uniform layer distribution. However, under special process requirements or equipment limitations, the application of flux is unavoidable. The main component of flux is rosin, which has strong viscosity and is corrosive. During soldering, it volatilizes into a mist suspended in the reducing gas shield or furnace chamber. When it encounters the cooled furnace chamber wall, it adheres to the inner wall, forming a highly viscous liquid. Excessive flux buildup flows down the furnace chamber wall to the bottom, causing contamination and affecting soldering quality. Furthermore, flux residue can reduce the heat dissipation efficiency of printed circuit boards (PCBs), affecting solder joint performance, and even interfering with temperature control, increasing equipment maintenance difficulty.

[0003] The utility model application with application number 202121634696 discloses a vacuum chamber with flux recovery function, which relates to the field of vacuum reflow soldering technology. It includes a chamber body, and recovery devices are provided on the inner side walls of the chamber. The recovery devices include mounting plates connected to the inner side walls of the chamber body. A recovery trough is opened on the top of the mounting plate. The recovery trough is connected to a guide plate. The guide plates are all arranged at an upward inclination. When a lot of flux adheres to the inner wall of the vacuum chamber, it flows down and after flowing on the guide plate, it will automatically flow into the recovery trough, avoiding flowing to the bottom of the vacuum chamber.

[0004] Its recycling device is installed on the inner side wall of the chamber. The drawback is that, under normal circumstances, the chamber is equipped with heating lamps, product platforms and other devices, and the internal structure is complicated. Because the recycling device is installed on the four side walls of the chamber, the usable space of the chamber is greatly reduced. In addition, the recycling device needs to be removed one by one to clean the flux, and it is not convenient to install it in a vacuum reflow oven with a chamber cover. Utility Model Content

[0005] To address the aforementioned shortcomings of existing technologies, this invention provides a vacuum reflow oven. In this invention, the upper cover of the oven chamber is placed over the lower chamber. The flux vaporizes due to heat, evaporating into a mist that floats within the oven chamber. The outer wall of the reflow hood contacts the upper cover. When it encounters the cooled outer wall of the reflow hood, it adheres to the inner wall of the reflow hood and condenses into a liquid. When a significant amount adheres, it flows downwards along the inner wall of the reflow hood due to gravity until it reaches the U-shaped reflow box. The combination of the reflow hood and the reflow box prevents flux from flowing into the lower chamber of the oven.

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

[0007] A vacuum reflow oven, comprising

[0008] The furnace chamber includes an upper chamber cover and a lower chamber, wherein the lower chamber is hinged to the upper chamber cover;

[0009] A reflux hood is installed in the upper cover of the chamber, with one side of the reflux hood being open and the opening of the reflux hood facing away from the inner wall of the upper cover of the chamber.

[0010] A reflux box is disposed in the upper cover of the chamber. The reflux box is shaped to match the reflux hood. The reflux box is fixed at the opening of the reflux hood. The reflux box has a reflux groove that covers the circumference of the opening of the reflux hood.

[0011] Furthermore, the back side of the reflux hood is fixed to the inner wall of the chamber cover, and the open edges of the reflux hood extend towards each other to form connecting ears, and the reflux hood is fixed to the reflux box through the connecting ears.

[0012] Furthermore, the cross-section of the reflux box is U-shaped, the inner side of the reflux groove is located near the edge of the connecting ear, and a gap is left between the outer side of the reflux groove and the reflux cover.

[0013] Furthermore, there are four connecting ears, and each connecting ear is fixed with a nut. The connecting ear is fixed to the bottom wall of the return channel by the nut.

[0014] Furthermore, the chamber cover is provided with at least one water-cooling channel. The water-cooling channel is located on the side of the chamber cover where the reflux box is installed, and the water-cooling channel is opened through the chamber cover. The water inlet of the water-cooling channel is provided on one side of the chamber cover, and the water outlet of the water-cooling channel is provided on the other side of the chamber cover.

[0015] Compared with existing technologies, the advantages of this solution are:

[0016] This invention provides a vacuum reflow oven. The upper cover of the oven chamber is placed over the lower chamber. The flux vaporizes due to heat, becoming a mist suspended within the oven chamber. The outer wall of the reflow hood contacts the upper cover. When it encounters the cooled outer wall of the reflow hood, it adheres to the inner wall and condenses into a liquid. When a large amount adheres, it flows down the inner wall of the reflow hood under gravity until it reaches the U-shaped reflow box. The combination of the reflow hood and the reflow box prevents flux from flowing into the lower chamber of the oven. Cleaning the oven chamber is simple; just open the upper cover. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of this vacuum reflow oven;

[0018] Figure 2 This is a cross-sectional view of a vacuum reflow oven;

[0019] Figure 3 This is a schematic diagram of the reflux box structure;

[0020] Figure 4 This is a schematic diagram of the return shroud structure.

[0021] The reference numerals in the attached figures are as follows:

[0022] Chamber top cover 1, water cooling channel 11, lower chamber 2, reflux hood 3, connecting ear 31, nut 32, reflux box 4, reflux groove 41. Detailed Implementation

[0023] The present invention will now be described in further detail with reference to the accompanying drawings.

[0024] A vacuum reflow oven, such as Figure 1 and Figure 2 As shown, it includes a furnace body chamber, which includes a chamber upper cover 1 and a lower chamber 2, wherein the lower chamber 2 is hinged to the chamber upper cover 1;

[0025] The reflux hood 3 is installed in the upper cover 1 of the chamber. One side of the reflux hood 3 is open and the opening of the reflux hood 3 is away from the inner wall of the upper cover 1 of the chamber.

[0026] The reflux box 4 is disposed in the upper cover 1 of the chamber. The reflux box 4 matches the shape of the reflux hood 3. The reflux box 4 is fixed at the opening of the reflux hood 3. The reflux box 4 has a reflux groove 41, which covers the edge of the opening of the reflux hood 3.

[0027] According to a specific embodiment of this utility model, the furnace chamber temperature is high during operation (upper limit 450℃). After the upper cover 1 of the chamber is placed on the lower chamber 2, the flux is cooled and liquefied on the reflux shroud 3. The reflux box 4 is fixed at the opening of the reflux shroud 3. When the upper cover 1 of the chamber is placed on the lower chamber 2, the side wall of the reflux box 4 is in a vertical state. The reflux box 4 has a reflux groove 41 for containing the liquefied flux. The reflux groove 41 covers the edge of the opening of the reflux shroud 3. The reflux shroud 3 is used to guide the liquefied flux into the reflux groove 41 of the reflux box 4. When the furnace chamber temperature drops to room temperature, the flux becomes solid.

[0028] In this embodiment, the specific structure of the chamber cover 1 is not limited. However, taking a rectangular structure as an example, the reflux hood 3 is designed to match the chamber cover 1, and the reflux box 4 is a square groove structure. The height of the reflux hood 3 is not limited, but the height of the reflux hood 3 is less than the thickness of the chamber cover 1, meaning the reflux hood 3 must be located inside the chamber cover 1. The area of ​​the reflux hood 3 can be slightly smaller than the area of ​​the chamber cover 1, so that after the reflux hood 3 is installed inside the chamber cover 1, there is a slight gap between the reflux hood 3 and the chamber cover 1, which facilitates the installation of the reflux box 4.

[0029] Furthermore, such as Figure 4 As shown, the back side of the reflux hood 3 is fixed to the inner wall of the chamber cover 1, and the open edges of the reflux hood 3 extend towards each other to form connecting ears 31. The reflux hood 3 is fixed to the reflux box 4 through the connecting ears 31.

[0030] Specifically, four screw holes are provided on the back side of the reflux shroud 3. The reflux shroud 3 is fixed to the inner wall of the chamber cover 1 through the four screw holes. That is, when the chamber cover 1 is placed on the lower chamber 2, the horizontally extended edge of the reflux shroud 3 forms a connecting lug 31. The square edge of the reflux shroud 3 forms four connecting lugs 31, and the four connecting lugs 31 are respectively fixed with nuts 32. The connecting lugs 31 are fixed to the bottom wall of the reflux channel 41 by the nuts 32. Of course, in this embodiment, the connecting lugs 31 can also be fixed to the edge of the reflux shroud 3 opening by welding.

[0031] Furthermore, such as Figure 3 As shown, the cross-section of the reflux box 4 is U-shaped. The inner side of the reflux groove 41 is located near the edge of the connecting ear 31. There is a gap between the outer side of the reflux groove 41 and the reflux cover 3. In this way, when the liquid flux flows down along the reflux cover 3, the reflux groove 41 can respectively hold the flux solidified on both sides of the reflux cover 3.

[0032] Furthermore, the chamber cover 1 is also provided with at least one water-cooling channel 11, which is located on the side of the chamber cover 1 where the reflux box 4 is installed, and the water-cooling channel 11 is opened through the chamber cover 1.

[0033] According to a specific embodiment of this utility model, water-cooling channels 11 can be distributed on the surface of the chamber cover 1. The main function of the water-cooling channels 11 is to cool the chamber cover 1 of the furnace cavity through the water-cooling circulation system, and at the same time form a temperature gradient between it and the return shroud 3. After the flux is heated, it vaporizes and becomes a mist suspended in the furnace cavity. The outer wall of the return shroud 3 contacts the chamber cover 1. When it encounters the cooled outer wall of the return shroud 3, it will adhere to the inner wall of the return shroud 3 and condense into liquid. When a large amount adheres, it will flow down the inner wall of the return shroud 3 under the action of gravity until it flows into the U-shaped return box 4. The return shroud 3 and the return box 4 work together to prevent the flux from flowing into the lower chamber 2 of the furnace cavity. When cleaning the furnace cavity, it is only necessary to open the chamber cover 1 for cleaning.

[0034] 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.

[0035] 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.

[0036] 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 vacuum reflow oven, characterized in that: include The furnace chamber includes an upper chamber cover and a lower chamber, wherein the lower chamber is hinged to the upper chamber cover; A reflux hood is installed in the upper cover of the chamber, with one side of the reflux hood being open and the opening of the reflux hood facing away from the inner wall of the upper cover of the chamber. A reflux box is disposed in the upper cover of the chamber. The reflux box is shaped to match the reflux hood. The reflux box is fixed at the opening of the reflux hood. The reflux box has a reflux groove that covers the circumference of the opening of the reflux hood.

2. The vacuum reflow soldering furnace according to claim 1, characterized in that: The back side of the reflux hood is fixed to the inner wall of the chamber cover, and the open edges of the reflux hood extend towards each other to form connecting ears. The reflux hood is fixed to the reflux box through the connecting ears.

3. A vacuum reflow soldering furnace according to claim 2, characterized in that: The cross-section of the reflux box is U-shaped. The inner side of the reflux groove is located near the edge of the connecting ear, and a gap is left between the outer side of the reflux groove and the reflux cover.

4. The vacuum reflow soldering furnace according to claim 3, characterized in that: There are four connecting ears, and each connecting ear is fixed with a nut. The connecting ear is fixed to the bottom wall of the return channel by the nut.

5. A vacuum reflow soldering furnace according to any one of claims 1-4, characterized in that: The chamber cover is also provided with at least one water-cooling channel. The water-cooling channel is located on the side of the chamber cover where the reflux box is installed, and the water-cooling channel is opened through the chamber cover. The water inlet of the water-cooling channel is provided on one side of the chamber cover, and the water outlet of the water-cooling channel is provided on the other side of the chamber cover.

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