A drying groove air isolation plate for reflow solder cleaning machine

Abstract

The utility model belongs to but is not limited to drying groove technical field, disclose a kind of drying groove air baffle for reflow soldering cleaning machine, the drying groove air baffle is four prism platform type, and the front air outlet is provided on table top, and side air outlet is provided in left and right side edge, and upper air outlet, lower air outlet are respectively provided in front and back side edge.The fixed hole is provided at the four corners of the drying groove air baffle, and the drying groove air baffle is fixed at the air outlet of drying groove body by the fixed hole.The utility model can realize airflow uniform distribution, heat energy efficient utilization and equipment stable operation.

Description

Technical Field

[0001] This utility model belongs to, but is not limited to, the field of drying tank technology, and particularly relates to a drying tank baffle plate for a reflow soldering cleaning machine. Background Technology

[0002] In the design of drying tanks for reflow soldering cleaning machines, a direct-blowing design is commonly used, where hot air is blown directly onto the workpiece surface vertically or at a fixed angle. While direct-blowing airflow (i.e., hot air blown directly onto the workpiece surface vertically or at a fixed angle) has advantages such as simple structure and low cost, it has revealed many problems in practical applications. For example, direct impact of hot air onto the workpiece causes the airflow to concentrate in the central area, while the edges and corners are significantly underheated. This uneven airflow distribution results in significant temperature differences on the workpiece surface; for example, the edges of DBC boards may be defective due to excessively low temperatures, and coating materials may exhibit color differences or reduced adhesion due to uneven drying. Furthermore, the direct-blowing airflow rebounds after impacting the workpiece, forming eddies, which not only prevents efficient use of heat energy but also increases energy consumption and noise pollution. To maintain the set temperature, the equipment needs to continuously increase its heating power, increasing energy consumption by 20%-30%, while the high-frequency noise generated by the eddies also affects the operating environment and equipment lifespan.

[0003] Existing technology discloses a drying device for a reflow soldering cleaning machine, in which hot air is blown onto the cleaned circuit board through multiple air ducts and nozzles to evaporate the moisture on its surface. Although the device has basic drying functions, its air duct structure is a fixed unidirectional layout, and the hot air path is linear, making it difficult to effectively dry the gaps and irregular surfaces of complex structural components. It is also easy to create temperature dead zones and airflow blind spots in local areas of the board.

[0004] The main problem with this technology is the lack of a structural mechanism for controlling and directing the hot air disturbance within the cavity. This results in uneven distribution of hot air and a unidirectional flow field within the cavity, making it difficult to cover all workpiece surfaces, especially creating drying dead zones for stacked or high-density devices. Furthermore, the device cannot flexibly adjust the direction and intensity of the hot air according to process requirements, limiting its adaptability to complex working conditions in high-end cleaning equipment. Utility Model Content

[0005] To address the problems existing in the prior art, this utility model provides a baffle plate for the drying tank of a reflow soldering cleaning machine.

[0006] This utility model is implemented as follows: a drying tank baffle for a reflow soldering cleaning machine. The drying tank baffle is a truncated quadrangular shape, with a front air outlet on the table surface, side air outlets on the left and right sides, and an upper air outlet and a lower air outlet on the front and rear sides, respectively.

[0007] Furthermore, the front air outlet is a strip-shaped opening arranged along the width of the countertop.

[0008] Furthermore, the side air outlet, upper air outlet, and lower air outlet are elongated or round openings, all arranged linearly along the edges.

[0009] Furthermore, a fixing hole is provided at each of the four corners of the windbreak plate body.

[0010] Furthermore, the fixing hole is a through hole, used for screw or pin installation and positioning.

[0011] Furthermore, the baffle plate is detachably installed on the inner wall of the drying tank body through the fixing hole and is connected to the air outlet of the drying tank body.

[0012] Based on the above technical solutions and the technical problems solved, the advantages and positive effects of the technical solution to be protected by this utility model are as follows: The core component of this invention is the drying tank baffle assembly, whose main structure includes a baffle body, a front air outlet, side air outlets, an upper air outlet, a lower air outlet, and fixing holes for positioning and fixing. The baffle body adopts an irregularly shaped bent structure design, possessing excellent airflow guiding characteristics. Its material is preferably a high-temperature resistant and corrosion-resistant metal sheet, ensuring long-term stable operation in high-temperature and humid environments. The front air outlet is arranged in a longitudinal strip shape to precisely guide the lower airflow towards the workpiece area, enhancing the airflow penetration capacity of the central hot zone and improving the efficiency of core heat exchange.

[0013] The baffle plate has upper and lower air outlets respectively, forming a layered airflow channel to achieve multi-layered penetration and circulation of hot air within the cavity. This layered air outlet structure breaks away from the traditional single-channel drying airflow mode, effectively suppressing eddy current buildup and temperature blind spots while uniformly coating the workpiece surface, significantly improving the uniformity of the temperature field within the cavity. The three-dimensional directional distribution of hot air enhances the overall heat exchange rate, making it particularly suitable for drying the gaps and grooves in components during reflow soldering cleaning.

[0014] In terms of the fixing structure, the fixing holes at both ends of the baffle plate cooperate with the slots on the side wall of the drying tank, achieving tool-free disassembly and assembly, precise positioning, and high-strength locking, which has good maintenance convenience and modular versatility. This structural arrangement not only improves the efficiency of daily equipment maintenance, but also allows the baffle plate to be adapted to multiple models of drying chambers, has strong system expansion capabilities, and meets the customized needs of different production line equipment.

[0015] This invention's drying tank baffle plate, through a rational multi-directional airflow structure design and airflow disturbance control, achieves a uniform distribution of airflow velocity and temperature fields in the drying area, significantly improving the drying rate and consistency of component surfaces after reflow soldering cleaning. In practical applications, this structure can effectively reduce heat loss, shorten the drying cycle, and meet the high standards of drying performance required for high-density circuit board cleaning processes, demonstrating clear industrial practical value and promising prospects for promotion. Attached Figure Description

[0016] Figure 1 This is a structural diagram of the air baffle plate for the drying tank of a reflow soldering cleaning machine provided in this embodiment of the utility model; Figure 2 This is a schematic diagram of the left side of the drying tank for a reflow soldering cleaning machine provided in this embodiment of the utility model; Figure 3 This is a schematic diagram of a drying tank for a reflow soldering cleaning machine provided in an embodiment of this utility model; In the diagram: 1. Drying tank body; 11. Air outlet; 2. Baffle plate; 21. Front air outlet; 22. Upper air outlet; 23. Lower air outlet; 24. Side air outlet; 25. Fixing hole. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this utility model clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this utility model.

[0018] like Figure 1 As shown in the figure, this utility model embodiment provides a drying tank baffle plate for a reflow soldering cleaning machine. The drying tank baffle plate is a truncated quadrangular shape, with a front air outlet on the table surface, side air outlets on the left and right sides, and upper and lower air outlets on the front and rear sides, respectively. Fixing holes are provided at the four corners of the drying tank baffle plate.

[0019] like Figure 3 As shown, the baffle plate of the drying tank is fixed to the air outlet of the drying tank body through fixing holes.

[0020] This utility model relates to a drying module component for reflow soldering cleaning equipment, specifically an air baffle structure disposed inside the drying tank body 1, which can effectively improve the hot air flow direction and air pressure distribution. This air baffle structure optimizes the uniformity of hot airflow distribution within the drying chamber, preventing localized overheating or the occurrence of drying dead zones, thereby improving overall drying efficiency and equipment thermal energy utilization.

[0021] like Figure 1As shown, the baffle plate 2 has a trapezoidal structure and is detachably installed on the inner wall of the drying tank body through fixing holes 24 on both sides. A set of front air outlets 21 are provided on the front of the baffle plate, arranged in a long, strip-shaped array, which can evenly guide the lower layer of hot airflow to the central area of ​​the cavity, achieving concentrated diffusion and directional control. The size and spacing of these front air outlets are precisely designed to match the cavity flow field characteristics, ensuring minimal wind resistance and optimized airflow stability.

[0022] The front and rear sides of the baffle plate are respectively provided with upper air outlet 22 and lower air outlet 23, which together form a layered air supply channel. Combined with the hot air circulation system, a multi-layered air field structure can be constructed, which promotes the hot air to exchange heat with the workpiece being dried from multiple angles and directions. This structure overcomes the technical defects of the existing technology, such as uneven local temperature and low drying efficiency caused by unidirectional air blowing.

[0023] like Figure 3 As shown, the drying tank body 1 has an overall box-like structure. Several ventilation holes or slots are pre-set on its inner wall corresponding to the air baffle plate area to facilitate quick positioning and stable installation of the air baffle plate assembly. The multiple air outlets 11 located on its side wall cooperate with the multiple air guide structures of the air baffle plate 2 to jointly form an airflow disturbance zone, increasing the frequency and coverage of airflow contact with the workpiece surface, and significantly improving the drying effect.

[0024] The baffle plate is installed in the lower middle part of the drying tank body, which does not obstruct the natural upward path of the airflow above, and can also effectively guide the hot air below to diffuse through multiple air outlet channels on the front, top and bottom. This structural design has good compatibility and modularity, making it easy to replace or adjust the airflow control module according to different cleaning tasks.

[0025] This utility model effectively improves the uniformity of hot air distribution, drying efficiency, and thermal energy utilization by adding a baffle plate assembly with a multi-directional air outlet structure to the drying tank. It overcomes the problems of simple structure and uncontrollable airflow in existing drying systems, and has obvious structural innovation and practical progress. It can provide a higher performance hot air drying solution for reflow soldering cleaning equipment, which meets the inventiveness and practicality requirements of patent authorization.

[0026] The working principle of this invention is as follows: When the cleaned welded parts are conveyed into the drying tank body 1, the central hot air source guides the heated high-temperature airflow through the air outlet 11 into the baffle plate. The baffle plate has a four-core structure, with a front air outlet 21 at the top, side air outlets 24 on the left and right sides, and upper air outlets 22 and lower air outlets 23 on the front and rear edges, respectively. Fixing holes 25 are provided at the four corners to firmly install the baffle plate onto the inner wall of the tank. This layout allows the hot air to be immediately divided into three independent airflow channels (upper, middle, and lower) and a single front layer after entering the baffle plate, laying the foundation for three-dimensional enveloping drying.

[0027] During operation, the airflow first forms a high-speed hot air curtain from the front air outlet 21, directly targeting the main heated surface of the workpiece to be dried, rapidly breaking up the liquid film on the workpiece surface. Simultaneously, the upper air outlet 22 and lower air outlet 23 spray hot air onto the top and bottom of the workpiece, respectively, while the side air outlet 24 sprays hot air onto the left and right sides of the workpiece. Utilizing the Couette sandwich effect generated by the temperature difference-density gradient, the hot air forms a circular circulation within the tank. At this time, the convective flow field flowing from the top to the bottom continuously carries away the evaporated water vapor and solvent residue from the workpiece surface, preventing secondary condensation.

[0028] To prevent cold air from flowing back into the tank and to precisely regulate the flow rate, the opening area and angle of each air outlet are designed with a differentiated distribution. The mounting holes 25, combined with positioning pins, allow for quick adjustment of the front and rear positions of the baffle plates according to different sizes or batches of workpieces. This coupling method of "zoned air supply + adjustable distance" not only ensures uniform hot air coverage and controllable turbulence intensity but also significantly shortens drying time, reduces energy consumption, and minimizes the risk of thermal stress on components due to localized overheating, thus ensuring long-term stable and efficient drying for the reflow soldering cleaning machine.

[0029] In existing reflow soldering cleaning equipment, hot air is delivered from a single point on the bottom or side wall of the drying tank. Due to the limited depth of the tank and the obstruction of PCB components, the airflow flows in a biased channel, easily forming "cold zones" in the dead corners of the chamber. This results in residual moisture on the component solder joints, incomplete flux evaporation, and the risk of localized overheating and burning. The pain points in the industry are concentrated in: ① Board temperature distribution ΔT>15 ℃; ② Limited drying cycle time, resulting in a decrease in production line OEE; ③ High power consumption of the hot air blower and high heat loss from exhaust.

[0030] This invention employs a truncated quadrangular baffle plate, utilizing the CFD-optimized "inverted cone" surface curvature and lead angle to create a uniform surrounding flow of the mainstream hot air around the baffle. The front outlet of the baffle handles axial directional jetting, while the left and right side outlets form shear-attached jets at an angle of θ≈60°. The upper and lower outlets establish symmetrical backflow to the top / bottom of the cavity. This multi-directional jet coupling weakens the uneven boundary layer thickness caused by the Coanda attachment effect, significantly improving the uniformity of the Nusselt number distribution within the tank.

[0031] The integrated staged throttling channels and equal-diameter orifice array within the baffle plate control the static pressure gradient within the tank within the range of 80–120 Pa, avoiding the sudden pressure drop caused by traditional large-opening structures. Through coupled thermal-fluid-structure analysis, the root mean square temperature deviation (RMS ΔT) decreased from 13.4 ℃ to 4.2 ℃, while the total pressure recovery coefficient increased by 18%, allowing for a reduction of 8–10% in heater power setting while maintaining a constant fan speed.

[0032] The baffle plate is equipped with Φ6 mm conical mounting holes at its four corners, which match the self-positioning arc sockets on the tank flange, enabling quick installation and removal in 3 seconds with a simple push and turn. The baffle plate is made of 5052-H34 anodized aluminum plate with a wall thickness of 2 mm, balancing thermal conductivity and corrosion resistance. High-temperature PTFE support rings are used between the plate and the tank to isolate vibration, eliminating the whistling generated in the fan's resonant frequency band of 250–400 Hz and reducing fastener fatigue.

[0033] The manufacturing process employs an integrated laser cutting, stretch forming, and friction stir welding process, avoiding air leakage caused by gaps in traditional riveting and assembly. The inner surface of the assembly platform is coated with 25 μm fluorocarbon, effectively inhibiting the condensation and adhesion of cleaning agent vapors. The cycle time for a single pressing of the entire part is 32 seconds, which reduces the cycle time by 46% for multi-piece welding solutions and increases the yield to 98.7%, meeting the requirements of a 15 k / h scale production line.

[0034] Compared to existing flat-plate windbreak + single nozzle solutions, this technology utilizes a quadrangular truncated pyramid multi-dimensional air outlet structure to achieve secondary distribution and dynamic compensation of the heat flow field without adding an additional air source. This represents an integrated innovation combining aerodynamic control mechanisms and structural integration. Mass production equipment verification shows that, under the same production capacity, energy consumption is reduced by 12.4%, drying time is shortened by 22%, and PCB yield is improved by 2.1%, fully demonstrating the industrial application value and technological innovation of this windbreak plate in the drying module of reflow soldering cleaning machines.

[0035] Example 1: Slotted Three-Way Air Outlet Structure In this embodiment, the baffle plate is made of a single sheet of 1.2 mm thick 304 stainless steel, laser-cut and bent into a frustum shape. The outer surface is sandblasted to reduce liquid residue. Four 25 mm × 4 mm strip-shaped air outlets are evenly spaced along the width of the plate. Six 20 mm × 3 mm strip-shaped side outlets are machined on the upper half of the left and right sides, with an inward inclination angle of 12°. Twenty-three 20 mm × 3 mm strip-shaped upper and lower air outlets are arranged on the front and rear sides, with an inward inclination angle of 10°, creating a counter-current airflow against the wall. The baffle plate has Φ6 mm through holes punched at its four corners and milled with 45° countersunk heads, allowing for quick docking and fixation with the inner wall grooves of the drying tank using M6 hexagon countersunk screws. The baffle plate is installed 40mm above the bottom of the tank. A 1 kW variable frequency hot air blower (rated air volume 800 m³ / h, maximum 130 °C) is used to supply air. Under the conditions of 110 °C and 70% air volume, a 100 mm × 80 mm printed circuit board is dried for 6 minutes. The residual liquid mass of a single board is controlled below 0.05 g.

[0036] Example 2: Micro-orifice and slotted nozzle This embodiment targets a mid-sized automotive ECU production line. The air deflector is enlarged to a top size of 1200 mm × 600 mm, made of 1.5 mm thick 5052 aluminum alloy sheet, stamped as a single piece, and then laminated with a 0.5 mm ceramic fiber insulation layer on the outside. Two rows of 36 Φ6 mm round holes are cut into the tabletop as front air outlets, staggered to improve jet uniformity. Three 350 mm × 5 mm louvered side air outlets are arranged on the left and right sides, with the louvers angled downwards and inwards by 15°. Seventy-two honeycomb-shaped Φ8 mm round holes are stamped on the lower half of the front and rear sides to serve as upper and lower air outlets. Φ5 mm through holes are pre-drilled at the four corners, secured with Φ4 mm flexible cylindrical pins for anti-loosening. Two 3 kW centrifugal hot air blowers are connected in parallel, communicating with the MES system via Ethernet to achieve automatic switching between 90 °C and 130 °C. This structure, in 130 °C and 100% airflow mode, can continuously dry an aluminum-cased ECU with dimensions of 150 mm × 120 mm × 40 mm for 8 minutes, reducing the residual liquid in the casing to 0.02 g / piece, and saving 18% of energy compared to unidirectional heating.

[0037] Example 3: Modular Design with Replaceable Nozzles The baffle plate body is welded from 1 mm thick SUS430 stainless steel, followed by electrophoretic coating to improve corrosion resistance. The front air outlet area is designed as a detachable ABS+30% glass fiber injection molded part, containing ten 30 mm × 4 mm slots. The upper air outlets on the left and right sides and the side air outlets on the front and rear sides all use 2 mm thick PPS high-temperature plastic microporous plates, with 120 holes of Φ4 mm diameter at the upper air outlet and 150 holes of Φ5 mm diameter at the lower air outlet. The nozzle modules are all connected by snap-fit, and can be individually disassembled and replaced within 30 seconds. The four corner fixing holes are designed as Φ6 mm × 10 mm horizontal waist holes, equipped with M5 bolts and spring washers, which can finely adjust the front and rear position of the baffle plate within ±5 mm to meet the clearance requirements of various fixture specifications. This embodiment is suitable for flexible small-batch cleaning lines, and the entire plate can be replaced within 20 seconds, reducing nozzle loss costs by 40%.

[0038] Example 4: Double-layer thermal insulation and pressure-resistant structure For vacuum-assisted high-temperature drying equipment, the baffle plate in this embodiment uses two layers of 1.2 mm 316L stainless steel plates, with TIG fully welded edges on all sides. The inner cavity is filled with 8 mm SiO2 aerogel insulation material, with a total wall thickness of 10.4 mm, capable of withstanding 140 °C and 0.12 MPa positive pressure. The front air outlet has fourteen 40 mm × 3 mm slots, with the nozzles tilted outwards at 5°. The left, right, front, and back sides combine nine 35 mm × 3 mm slots and sixty Φ6 mm round holes, staggered vertically to enhance local turbulence. Φ8 mm through holes are drilled at the four corners, and 60° conical countersunk holes are machined. A4-70 stainless steel screws are used for sealing connection to the drying tank flange via graphite washers. After 1000 hours of continuous operation at 140 °C and 0.1 MPa, the baffle plate showed no deformation or leakage, and the outer wall temperature remained below 60 °C, meeting the application requirements for high pressure, high temperature, and safety protection.

[0039] The four embodiments provide specific and feasible technical solutions from multiple perspectives, including size, materials, nozzle type, installation method, and applicable working conditions, fully demonstrating the feasibility, stability, and adaptability of the drying tank baffle plate described in this utility model.

[0040] In the description of this utility model, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and 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, and therefore should not be construed as a limitation of this utility model. In addition, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0041] The above description is only a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any modifications, equivalent substitutions and improvements made by those skilled in the art within the technical scope disclosed in this utility model, and within the spirit and principles of this utility model, should be included within the protection scope of this utility model.

Claims

1. A baffle plate for a drying tank of a reflow soldering cleaning machine, characterized in that, It includes a frustum-shaped windbreak panel body, with multiple front air outlets on the platform surface, multiple side air outlets on the left and right sides, and multiple upper air outlets and lower air outlets on the front and rear sides respectively.

2. The drying tank baffle plate as described in claim 1, characterized in that, The front air outlet is a strip-shaped opening arranged along the width of the countertop.

3. The drying tank baffle plate as described in claim 1, characterized in that, The side air outlet, upper air outlet, and lower air outlet are elongated or round openings, all arranged linearly along the edge.

4. The drying tank baffle plate as described in claim 1, characterized in that, Each of the four corners of the windbreak panel body is provided with a fixing hole.

5. The drying tank baffle plate as described in claim 4, characterized in that, The fixing hole is a through hole, used for screw or pin installation and positioning.

6. The drying tank baffle plate as described in any one of claims 4 or 5, characterized in that, The baffle plate is detachably installed on the inner wall of the drying tank body through fixing holes and is connected to the air outlet of the drying tank body.

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