An efficient and energy-saving lead-free solder bar melting furnace and its melting method

Abstract

The present invention discloses an efficient and energy-saving lead-free solder bar melting furnace and its melting method, belonging to the technical field of lead-free solder bar melting, including: a furnace wall, an insulating cylinder is fixedly installed inside the furnace wall, a heat conduction cylinder is fixedly installed inside the insulating cylinder, the heat conduction cylinder is fixedly installed on the inner ring surface of the insulating cylinder through a connecting rod on the outer surface of the upper end, a ring groove is formed between the insulating cylinder and the heat conduction cylinder, an electromagnetic heating coil is fixedly installed inside the ring groove, a heat insulating cover is fixedly installed on the upper surface of the furnace wall, a wind circulation mechanism is fixedly installed on the upper surface of the heat insulating cover, a placement plate is fixedly installed inside the heat conduction cylinder through a connecting ring on the outer surface, an expansion ring is fixedly installed on the outer surface of the placement plate, a storage plate is communicated and installed on the lower surface of the expansion ring, a liquid outlet is opened at one end of the storage plate, and a liquid discharge mechanism is rotatably installed inside the liquid outlet. Through the design of the wind circulation mechanism in this application, the combined use of the centrifugal impeller and the electromagnetic heating coil forms a hot air circulation, which helps to improve the melting quality and reduce energy consumption.

Description

Technical Field

[0001] The present invention relates to the technical field of lead-free solder bar melting, and specifically to an energy-efficient lead-free solder bar melting furnace and its melting method. Background Art

[0002] With the rapid development of the electronics industry, as an important electronic welding material, the quality and production efficiency of lead-free solder bars directly affect the performance and manufacturing cost of electronic products. Against the backdrop of increasing environmental awareness and rising energy costs, the disadvantages of high energy consumption and low efficiency of traditional lead-free solder bar melting furnaces have become increasingly prominent. Developing a lead-free solder bar melting furnace that can not only meet the requirements of high-efficiency production but also effectively reduce energy consumption has become the key to breaking through the development bottleneck in the industry.

[0003] For example, the patent with the national authorized patent publication number CN103402671B discloses a melting furnace for metal melting, which can efficiently cool the ingot pulled out from the mold installed in the melting furnace, achieving the effect of being able to efficiently produce ingots. And, a device structure is provided that can produce multiple ingots with high efficiency and maintain high quality by means of a single furnace bed. The melting furnace for metal melting includes: a furnace bed that holds the molten metal generated from the molten raw material; a mold into which the molten metal is filled; a drawing fixture provided below the mold for drawing the cooled and solidified ingot downward; a cooling component that cools the ingot; and an outer cylinder that isolates the above components from the atmosphere. One or more molds and drawing fixtures are arranged in the outer cylinder, and the cooling component is arranged between the outer cylinder and the ingot or between multiple ingots.

[0004] However, during the process of melting metal blocks, the above-mentioned melting furnace for metal melting does not have the function of evenly distributing the heat in the furnace. Therefore, additional energy consumption is required to make the temperature in the furnace uniform, which will lead to an extended melting time. Moreover, during the process of draining the liquid, it does not have the convenient function of pouring and blocking the metal liquid, and cannot accurately control the discharge amount of the metal liquid. Summary of the Invention

[0005] The purpose of the present invention is to provide an energy-efficient lead-free solder bar melting furnace and its melting method to solve the problems mentioned in the above background art, that is, during the process of melting metal blocks, it does not have the function of evenly distributing the heat in the furnace, so additional energy consumption is required to make the temperature in the furnace uniform, which will lead to an extended melting time, and during the process of draining the liquid, it does not have the convenient function of pouring and blocking the metal liquid.

[0006] To achieve the above purpose, the present invention provides the following technical solutions:

[0007] An efficient and energy-saving lead-free solder bar melting furnace, comprising: a furnace wall, an insulating cylinder is fixedly installed inside the furnace wall, a heat-conducting cylinder is fixedly installed inside the insulating cylinder, the heat-conducting cylinder is fixedly installed on the inner ring surface of the insulating cylinder through a connecting rod on the outer surface of the upper end, the heat-conducting cylinder is suspended inside the insulating cylinder, and the heat-conducting cylinder is communicated with the insulating cylinder through the overhead space on the lower surface, a ring groove is formed between the insulating cylinder and the heat-conducting cylinder, and an electromagnetic heating coil is fixedly installed in the ring groove of the insulating cylinder and the heat-conducting cylinder;

[0008] Wherein, a heat-insulating cover is fixedly installed on the upper surface of the furnace wall, a wind circulation mechanism is fixedly installed on the upper surface of the heat-insulating cover, and the air supply end of the wind circulation mechanism rotates through to the inside of the heat-conducting cylinder, so that the wind circulation mechanism can suck the wind inside the heat-conducting cylinder and discharge the wind into the ring groove through the flow channel on the outer surface of the wind circulation mechanism through rotation and be heated by the electromagnetic heating coil, and the heated wind can be discharged into the heat-conducting cylinder again through the overhead area on the lower surface of the heat-conducting cylinder to heat and melt the lead-free solder bars placed on the placing tray. A connecting ring is fixedly installed on the outer surface of the placing tray, and the placing tray is fixedly installed inside the heat-conducting cylinder through the connecting ring on the outer surface, and air vents are formed in the connecting ring;

[0009] Wherein, an expansion ring is fixedly installed on the outer surface of the placing tray at the lowermost layer, a storage tray is communicated and installed on the lower surface of the expansion ring, the storage tray is fixedly installed on the lower surface of the furnace wall, and the placing tray is in a grid-shaped through state, so that the melted tin liquid can fall into the storage tray through the mesh holes of the placing tray for centralized storage. A liquid outlet is formed at one end of the storage tray, and a liquid discharge mechanism is rotatably installed in the liquid outlet, and the liquid discharge mechanism can be communicated with the liquid outlet through flipping, so that the tin liquid stored in the storage tray can be discharged through the liquid discharge mechanism.

[0010] Preferably, windows are formed on the outer surfaces of the furnace wall, the insulating cylinder and the heat-conducting cylinder, and sliding doors are slidably sealed on the outer surfaces of the furnace wall, the insulating cylinder and the heat-conducting cylinder, so that the sliding doors can slide to seal the windows, and the three sliding doors are fixedly connected together through connecting rods, so that when the sliding doors are pulled and slid open, the windows of the furnace wall, the insulating cylinder and the heat-conducting cylinder can be unfolded together.

[0011] Preferably, the sliding door sliding on the outer surface of the furnace wall also slides through the support rod, and the support rod is fixedly installed on the outer surface of the furnace wall.

[0012] Preferably, the wind circulation mechanism includes a frame plate, the frame plate is fixedly installed on the upper surface of the heat-insulating cover, a motor is fixedly installed on the upper surface of the frame plate, the output shaft of the motor rotates through to the heat-conducting cylinder of the furnace wall, and a centrifugal impeller is fixedly installed on the lower surface of the output shaft of the motor.

[0013] Preferably, when the centrifugal impeller is driven by the motor to rotate, the air pressure below the centrifugal impeller is reduced, forming a relatively low-pressure area. As a result, the air below can be "sucked" towards the centrifugal impeller. After the air entering the centrifugal impeller is accelerated, it will be blown into the annular groove between the heat-conducting cylinder and the heat-insulating cylinder through the flow channel of the centrifugal impeller and heated by the electromagnetic heating coil.

[0014] Preferably, the liquid discharge mechanism includes a liquid discharge pipe rotatably installed in the liquid outlet. The lower surface of the liquid discharge pipe is provided with a liquid inlet, so that the liquid discharge pipe can be rotated to turn the liquid inlet open and communicate with the liquid outlet, and thus the tin liquid in the storage tray can be discharged from the liquid discharge pipe through the liquid inlet.

[0015] Preferably, a connecting plate is fixedly installed on the upper surface of the liquid discharge pipe. A guiding groove is formed in the connecting plate, and a sliding column is fixedly installed in the guiding groove. A plug-in plate is slidably installed on the outer surface of the sliding column in the guiding groove. In this way, after the liquid discharge pipe is turned over and flattened, the connecting plate can be flush with one group of support rods on the outer surface of the furnace wall, the plug-in plate slidably installed in the connecting plate can be slid into the support rod, and the flattened liquid discharge pipe can block the liquid outlet.

[0016] Preferably, a spring is sleeved on the outer surface of the sliding column, and the two ends of the spring respectively abut between the lower surface in the guiding groove and the upper surface of the plug-in plate.

[0017] Preferably, one end of the plug-in plate is fixedly installed with a pressing plate, and the pressing plate slides out from the sliding groove. The sliding groove is formed at one end of the connecting plate and communicates with the guiding groove, so that the staff can drive the plug-in plate to slide into the guiding groove by pressing the pressing plate.

[0018] The present invention also provides a melting method for a high-efficiency and energy-saving lead-free solder bar melting furnace, including the following steps:

[0019] S1. When melting lead-free solder bars, first slide open the sliding door to expose the windows of the furnace wall and the heat conduction cylinder. Then, the staff can place the lead-free solder bar raw materials on the placement tray. Subsequently, push the sliding door to close the window of the heat conduction cylinder. Then, start the electromagnetic heating coil and the motor. The motor can drive the centrifugal impeller to rotate at the upper end of the heat conduction cylinder. The rotation of the centrifugal impeller will suck the air in the heat conduction cylinder and, through rotation, let the air be discharged into the annular groove through the flow channel on the outer surface of the centrifugal impeller and be heated by the electromagnetic heating coil. The heated air can then be discharged back into the heat conduction cylinder through the overhead area on the lower surface of the heat conduction cylinder to conduct heat exchange with the lead-free solder bars placed on the placement tray. Moreover, it will also be interconnected through the air vents opened on the connecting ring on the outer surface of the placement tray, so that the heated air will be sucked in again and discharged into the annular groove for secondary heating and then discharged. This process is repeated, which can enable the hot air to accelerate the uniform distribution of heat in the heat conduction cylinder, enable the lead-free solder bars to absorb a large amount of heat in a short time, quickly reach the melting point, and speed up the melting speed, thereby achieving the purpose of energy conservation and consumption reduction and rapid and uniform heat distribution;

[0020] S2. After reaching the melting point of the solder bar, the molten tin can fall into the storage tray through the mesh holes of the placement tray for centralized storage;

[0021] S3. When discharging the molten tin in the storage tray, the staff can place a receiving container at the lower end of the liquid outlet pipe. Then, press down the pressing plate to drive the inserted plate to slide into the guide groove of the connecting plate. During the process of the inserted plate sliding into the guide groove, it will simultaneously press against one end of the spring. Thus, the spring can apply an elastic thrust to the inserted plate. The inserted plate that slides into the guide groove can then be pulled out from the support rod, which releases the rotation restriction on the liquid outlet pipe. Subsequently, the liquid outlet pipe can automatically turn downward to align the liquid inlet opening opened on the lower surface with the liquid outlet, so that the molten tin in the storage tray can be discharged from the liquid outlet pipe through the liquid inlet opening until the required amount of molten tin is discharged. Then, the staff can turn the liquid outlet pipe upward to make the liquid inlet opening opened on the lower surface of the liquid outlet pipe fit against the upper surface of the liquid outlet to be blocked. The flattened liquid outlet pipe will also block the liquid outlet. Moreover, the flattened liquid outlet pipe can make the connecting plate flush with the support rod on the outer surface of the furnace wall. Thus, the inserted plate that slides into the guide groove can slide back into the support rod again through the elastic thrust applied by the spring to lock the rotation of the liquid outlet pipe, that is, it realizes turning downward to discharge liquid, and turning upward can block the liquid outlet to stop discharging liquid, enabling the staff to control the discharging time of the liquid outlet pipe according to needs, thereby accurately discharging the required amount of molten tin, which helps to achieve precise control of the amount of molten tin used in the production process, avoid waste or insufficient amount of molten tin, and is beneficial to improving product quality and production stability.

[0022] Compared with the prior art, the beneficial effects of the present invention are:

[0023] 1. Through the design of the furnace wall, sliding door, electromagnetic heating coil, placement tray, storage tray, air circulation mechanism and liquid discharge mechanism, when melting lead-free solder bars, the sliding door can be first slid open to expose the windows of the furnace wall and the heat conduction cylinder. Subsequently, the staff can place the lead-free solder bar raw materials in the placement tray. Then, the sliding door can be pushed to close the window of the heat conduction cylinder. Then, the electromagnetic heating coil and the air circulation mechanism can be started. As a result, the air circulation mechanism can suck the air in the heat conduction cylinder and, through rotation, let the air be discharged into the annular groove through the flow channel on the outer surface of the air circulation mechanism and be heated by the electromagnetic heating coil. The heated air can then be discharged into the heat conduction cylinder again through the overhead area on the lower surface of the heat conduction cylinder to conduct heat exchange with the lead-free solder bars placed in the placement tray. After reaching the melting point of the solder bars, the molten tin can fall into the storage tray through the mesh holes of the placement tray for centralized storage. When it is necessary to discharge the molten tin in the storage tray, the staff can place a receiving container at the lower end of the liquid discharge pipe. Then, the liquid discharge mechanism can be pressed down to communicate with the liquid outlet of the storage tray, so that the molten tin stored in the storage tray can be discharged through the liquid discharge mechanism. Until the required amount of molten tin is discharged, the staff can flip the liquid discharge mechanism upward to flatten it. The flattened liquid discharge mechanism can then block the liquid outlet, that is, it realizes downward flipping for liquid discharge and upward flipping to block the liquid outlet to stop liquid discharge. It enables the staff to control the liquid discharge time of the liquid discharge pipe as needed. Moreover, the combined use of the air circulation mechanism and the electromagnetic heating coil enables the air to be sucked in, heated and then discharged into the heat conduction cylinder to form a hot air circulation. This circulation method accelerates the uniform distribution of heat in the heat conduction cylinder, makes the lead-free solder bars heat more evenly, reduces the situation of local overheating or overcooling, and helps to improve the melting quality and reduce energy consumption.

[0024] 2. Through the design of the motor, centrifugal impeller, heat insulation cylinder and heat conduction cylinder, after placing the lead-free solder bar raw materials in the placement tray, the electromagnetic heating coil and the motor can be started. The motor can drive the centrifugal impeller to rotate at the upper end of the heat conduction cylinder. The rotation of the centrifugal impeller will suck the air in the heat conduction cylinder and, through rotation, let the air be discharged into the annular groove through the flow channel on the outer surface of the centrifugal impeller and be heated by the electromagnetic heating coil. The heated air can then be discharged into the heat conduction cylinder again through the overhead area on the lower surface of the heat conduction cylinder to conduct heat exchange with the lead-free solder bars placed in the placement tray. And it will also communicate with each other through the air vents opened on the connecting ring on the outer surface of the placement tray, so that the heated air will be sucked in and discharged into the annular groove again for secondary heating and then discharged. In this way, the hot air can accelerate the uniform distribution of heat in the heat conduction cylinder, can contact the lead-free solder bars comprehensively and evenly, make the solder bars reach the melting point faster, and by continuously sucking, heating and circulating the air by the centrifugal impeller, it is equivalent to increasing the frequency and intensity of heat transfer, greatly shortening the melting time and reducing energy consumption, and improving production efficiency.

[0025] 3. Through the design of the liquid outlet pipe, the liquid inlet, the connecting plate, the plug-in plate, the spring and the pressing plate, when discharging the tin liquid in the storage disk, the staff can place a receiving container at the lower end of the liquid outlet pipe, and then press the pressing plate downward to drive the plug-in plate to slide into the guide groove of the connecting plate. During the process of the plug-in plate sliding into the guide groove, it will press on one end of the spring, so that the spring can apply an elastic thrust to the plug-in plate, and the plug-in plate sliding into the guide groove can be pulled out from the support rod, that is, the rotation restriction of the liquid outlet pipe is released, and then the liquid outlet pipe can be automatically turned downward to turn the liquid inlet opened on the lower surface to be connected with the liquid outlet, so that the tin liquid in the storage disk can be discharged from the liquid outlet pipe through the liquid inlet until the required amount of tin liquid is discharged. Afterwards, the staff can flip the liquid outlet pipe upwards to make the liquid inlet opened on the lower surface of the liquid outlet pipe fit into the upper surface of the liquid outlet and be blocked, and the turned and flattened liquid outlet pipe will also block the liquid outlet together, and the flattened liquid outlet pipe can make the connecting plate flush with the support rod on the outer surface of the furnace wall, so that the plug-in plate retracted into the guide groove can be slid into the support rod again through the elastic thrust applied by the spring to lock the rotation of the liquid outlet pipe, that is, flipping downward to discharge liquid, and flipping upward to block the liquid outlet to stop liquid discharge, so that the staff can control the liquid discharge time of the liquid outlet pipe as needed, so as to accurately discharge the required amount of tin liquid, and the whole operation process is simple and intuitive, without the need for complicated operating steps and tools, reducing the operating difficulty of the staff. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the overall structure of the high-efficiency and energy-saving lead-free tin bar melting furnace of the present invention;

[0027] Figure 2 It is a structural schematic diagram of the placement tray of the present invention;

[0028] Figure 3 It is a structural schematic diagram of the electromagnetic heating coil of the present invention;

[0029] Figure 4 It is a schematic structural diagram of a three-layer sliding door of the present invention;

[0030] Figure 5 It is a structural schematic diagram of the air circulation mechanism of the present invention;

[0031] Figure 6 It is a structural schematic diagram of the wind circulation direction between the heat insulation tube and the heat conduction tube of the present invention;

[0032] Figure 7 It is a structural schematic diagram of the connecting plate and the plug-in plate of the present invention;

[0033] Figure 8 It is a schematic structural diagram of the liquid discharge mechanism of the present invention.

[0034] In the figure: 1. Furnace wall; 101. Heat insulation cover; 102. Slide door; 103. Heat insulation cylinder; 104. Heat conduction cylinder; 105. Electromagnetic heating coil; 106. Placing tray; 107. Connecting ring; 108. Expansion ring; 109. Storage tray; 110. Liquid outlet; 2. Air circulation mechanism; 201. Motor; 202. Frame plate; 203. Centrifugal impeller; 3. Liquid discharge mechanism; 301. Liquid discharge pipe; 302. Liquid inlet; 303. Connecting plate; 304. Sliding groove; 305. Insertion plate; 306. Pressing plate; 307. Spring; 308. Slide column; 309. Guide groove; 4. Support rod. Specific embodiments

[0035] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

[0036] As Figures 1 - 4 shown, this embodiment provides an energy-efficient lead-free solder bar melting furnace, including: a furnace wall 1, a heat insulation cylinder 103 is fixedly installed inside the furnace wall 1, a heat conduction cylinder 104 is fixedly installed inside the heat insulation cylinder 103, the heat conduction cylinder 104 is fixedly installed on the inner ring surface of the heat insulation cylinder 103 through a connecting rod on the outer surface of the upper end, the heat conduction cylinder 104 is suspended in the heat insulation cylinder 103, and the heat conduction cylinder 104 communicates with the heat insulation cylinder 103 through the overhead space on the lower surface. An annular groove is formed between the heat insulation cylinder 103 and the heat conduction cylinder 104, and an electromagnetic heating coil 105 is fixedly installed in the annular groove between the heat insulation cylinder 103 and the heat conduction cylinder 104;

[0037] Among them, a heat insulation cover 101 is fixedly installed on the upper surface of the furnace wall 1, an air circulation mechanism 2 is fixedly installed on the upper surface of the heat insulation cover 101, and the air supply end of the air circulation mechanism 2 rotates and penetrates into the heat conduction cylinder 104, so that the air circulation mechanism 2 can suck the air in the heat conduction cylinder 104 and discharge the air into the annular groove through the flow channel on the outer surface of the air circulation mechanism 2 by rotation to be heated by the electromagnetic heating coil 105. The heated air can then be discharged into the heat conduction cylinder 104 again through the overhead area on the lower surface of the heat conduction cylinder 104 to heat and melt the lead-free solder bars placed in the placing tray 106. A connecting ring 107 is fixedly installed on the outer surface of the placing tray 106, and the placing tray 106 is fixedly installed in the heat conduction cylinder 104 through the connecting ring 107 on the outer surface, and air vents are provided on the connecting ring 107;

[0038] Among them, an expansion ring 108 is fixedly installed on the outer surface of the placement tray 106 at the bottommost layer. A storage tray 109 is communicatively installed on the lower surface of the expansion ring 108. The storage tray 109 is fixedly installed on the lower surface of the furnace wall 1. The placement tray 106 is in a grid-like through shape, so that the molten tin liquid can fall into the storage tray 109 through the mesh holes of the placement tray 106 for centralized storage. An outlet 110 is opened at one end of the storage tray 109. A liquid discharge mechanism 3 is rotatably installed in the outlet 110. The liquid discharge mechanism 3 can be connected to the outlet 110 through flipping, so that the tin liquid stored in the storage tray 109 can be discharged through the liquid discharge mechanism 3.

[0039] Windows are opened on the outer surfaces of the furnace wall 1, the heat insulation cylinder 103, and the heat conduction cylinder 104. Sliding doors 102 are slidably sealed on the outer surfaces of the furnace wall 1, the heat insulation cylinder 103, and the heat conduction cylinder 104, so that the sliding doors 102 can slide to seal the windows. Moreover, the three groups of sliding doors 102 are fixedly connected together by connecting rods, so that when the sliding doors 102 are pulled and slid open, the windows of the furnace wall 1, the heat insulation cylinder 103, and the heat conduction cylinder 104 can be unfolded together. The sliding door 102 sliding on the outer surface of the furnace wall 1 also slides through the support rod 4 at the same time. The support rod 4 is fixedly installed on the outer surface of the furnace wall 1.

[0040] Through the design of the furnace wall 1, the sliding door 102, the electromagnetic heating coil 105, the placing tray 106, the storage tray 109, the air circulation mechanism 2 and the liquid discharge mechanism 3, when melting the lead-free solder bar, the sliding door 102 can be first slid open to expose the windows of the furnace wall 1 and the heat conduction cylinder 104. Subsequently, the staff can place the lead-free solder bar raw materials in the placing tray 106. Then, the sliding door 102 can be pushed to close the window of the heat conduction cylinder 104. Subsequently, the electromagnetic heating coil 105 and the air circulation mechanism 2 can be started. Thereby, the air circulation mechanism 2 can suck the air in the heat conduction cylinder 104 and, through rotation, discharge the air into the annular groove through the flow channel on the outer surface of the air circulation mechanism 2 to be heated by the electromagnetic heating coil 105. The heated air can then be discharged into the heat conduction cylinder 104 again through the overhead area on the lower surface of the heat conduction cylinder 104 to perform heat exchange on the lead-free solder bars placed in the placing tray 106. After reaching the melting point of the solder bar, the molten tin can fall into the storage tray 109 through the mesh holes of the placing tray 106 for centralized storage. When it is necessary to discharge the molten tin in the storage tray 109, the staff can place a receiving container at the lower end of the liquid discharge pipe 301. Then, the liquid discharge mechanism 3 can be pressed down to communicate with the liquid outlet 110 of the storage tray 109, so that the molten tin stored in the storage tray 109 can be discharged through the liquid discharge mechanism 3. Until the required amount of molten tin is discharged, the staff can turn the liquid discharge mechanism 3 upward to flatten it. The flattened liquid discharge mechanism 3 can then block the liquid outlet 110, that is, it realizes downward turning for liquid discharge and upward turning to block the liquid outlet 110 to stop liquid discharge, enabling the staff to control the liquid discharge time of the liquid discharge pipe 301 as needed. And the combined use of the air circulation mechanism 2 and the electromagnetic heating coil 105 enables the air to be sucked in, heated and then discharged into the heat conduction cylinder 104 to form a hot air circulation. This circulation method accelerates the uniform distribution of heat in the heat conduction cylinder 104, makes the lead-free solder bars heat more evenly, reduces the situation of local overheating or overcooling, and helps to improve the melting quality and reduce energy consumption.

[0041] As Figures 5 - 6 shown, the air circulation mechanism 2 includes a frame plate 202. The frame plate 202 is fixedly installed on the upper surface of the heat insulation cover 101. A motor 201 is fixedly installed on the upper surface of the frame plate 202. The output shaft of the motor 201 rotates through the heat conduction cylinder 104 of the furnace wall 1, and a centrifugal impeller 203 is fixedly installed on the lower surface of the output shaft of the motor 201.

[0042] Thus, when the centrifugal impeller 203 is driven by the motor 201 to rotate, the air pressure below the centrifugal impeller 203 will be reduced, forming a relatively low-pressure area. Thereby, the air below can be "sucked" towards the centrifugal impeller 203. After the air entering the centrifugal impeller 203 is accelerated, it will be blown into the annular groove between the heat conduction cylinder 104 and the heat insulation cylinder 103 through the flow channel of the centrifugal impeller 203 to be heated by the electromagnetic heating coil 105.

[0043] Through the design of the motor 201, centrifugal impeller 203, heat insulation cylinder 103 and heat conduction cylinder 104, after placing the raw material of the lead-free solder bar in the placement tray 106, the electromagnetic heating coil 105 and the motor 201 can be started. The motor 201 can drive the centrifugal impeller 203 to rotate at the upper end of the heat conduction cylinder 104. The rotation of the centrifugal impeller 203 will suck the air in the heat conduction cylinder 104 and let the air be discharged into the annular groove through the flow channel on the outer surface of the centrifugal impeller 203 by rotation and be heated by the electromagnetic heating coil 105. The heated air can be discharged into the heat conduction cylinder 104 again through the overhead area on the lower surface of the heat conduction cylinder 104 to conduct heat exchange with the lead-free solder bars placed in the placement tray 106. Moreover, the air will pass through the air vents opened on the connecting ring 107 on the outer surface of the placement tray 106 and be interconnected, so that the heated air can be sucked in again and discharged into the annular groove for secondary heating and then discharged. This process is repeated, thereby enabling the hot air to accelerate the uniform distribution of heat in the heat conduction cylinder 104, enabling the hot air to contact the lead-free solder bars comprehensively and uniformly, making the solder bars reach the melting point faster. And by continuously sucking, heating and circulating the air through the centrifugal impeller 203, it is equivalent to increasing the frequency and intensity of heat transfer, greatly shortening the melting time and reducing energy consumption, and improving production efficiency.

[0044] As Figures 7 - 8 shown, the liquid discharge mechanism 3 includes a liquid discharge pipe 301. The liquid discharge pipe 301 is rotatably installed in the liquid discharge port 110. A liquid inlet 302 is opened on the lower surface of the liquid discharge pipe 301, so that the liquid discharge pipe 301 can be rotated to turn the liquid inlet 302 open and communicate with the liquid discharge port 110, and then the tin liquid in the storage tray 109 can be discharged from the liquid discharge pipe 301 through the liquid inlet 302.

[0045] Among them, a connecting plate 303 is fixedly installed on the upper surface of the liquid discharge pipe 301. A guiding groove 309 is opened in the connecting plate 303. A sliding column 308 is fixedly installed in the guiding groove 309. An inserting plate 305 is slidably installed on the outer surface of the sliding column 308 in the guiding groove 309. After the liquid discharge pipe 301 is turned over and flattened, the connecting plate 303 can be flush with one group of support rods 4 on the outer surface of the furnace wall 1. The inserting plate 305 slidably installed in the connecting plate 303 can be slid into the support rod 4, and the flattened liquid discharge pipe 301 can block and separate the liquid discharge port 110. A spring 307 is sleeved on the outer surface of the sliding column 308. The two ends of the spring 307 respectively abut between the lower surface in the guiding groove 309 and the upper surface of the inserting plate 305. One end of the inserting plate 305 is fixedly installed with a pressing plate 306. The pressing plate 306 slides out from the sliding groove 304. The sliding groove 304 is opened at one end of the connecting plate 303 and communicates with the guiding groove 309, so that the staff can drive the inserting plate 305 to slide into the guiding groove 309 by pressing the pressing plate 306.

[0046] Through the design of the liquid outlet pipe 301, the liquid inlet 302, the connecting plate 303, the inserted plate 305, the spring 307 and the pressing plate 306, when discharging the tin liquid in the storage tray 109, it is possible for the staff to place a receiving container at the lower end of the liquid outlet pipe 301. Subsequently, the pressing plate 306 can be pressed down to drive the inserted plate 305 to slide into the guiding groove 309 of the connecting plate 303. During the process of the inserted plate 305 sliding into the guiding groove 309, it will simultaneously press against one end of the spring 307. Thus, the spring 307 can exert an elastic pushing force on the inserted plate 305. The inserted plate 305 that has slid into the guiding groove 309 can then be pulled out from the support rod 4, which releases the rotation restriction on the liquid outlet pipe 301. Subsequently, the liquid outlet pipe 301 can automatically flip downward so that the liquid inlet 302 opened on the lower surface is flipped to communicate with the liquid outlet 110. As a result, the tin liquid in the storage tray 109 can pass through the liquid inlet 302 and be discharged from the liquid outlet pipe 301 until the required amount of tin liquid is discharged. Then, the staff can flip the liquid outlet pipe 301 upward to make the liquid inlet 302 opened on the lower surface of the liquid outlet pipe 301 fit against the upper surface of the liquid outlet 110 and be blocked. The flattened liquid outlet pipe 301 will also block the liquid outlet 110 together. Moreover, the flattened liquid outlet pipe 301 can make the connecting plate 303 flush with the support rod 4 on the outer surface of the furnace wall 1. Therefore, the inserted plate 305 that has slid into the guiding groove 309 can slide back into the support rod 4 again under the elastic pushing force exerted by the spring 307 to lock the rotation of the liquid outlet pipe 301. That is, it realizes discharging liquid by flipping downward and can block the liquid outlet 110 to stop discharging liquid by flipping upward, enabling the staff to control the discharging time of the liquid outlet pipe 301 according to needs, thereby accurately discharging the required amount of tin liquid. And the whole operation process is simple and intuitive, without complex operation steps and tools, reducing the operation difficulty of the staff.

[0047] Among them, in this embodiment, a hot air circulation efficiency factor equation is introduced, and the equation form is as follows:

[0048] , where:

[0049] ηh: hot air circulation efficiency factor (dimensionless);

[0050] w: rotational speed of the centrifugal impeller (rad / s);

[0051] P e : electromagnetic heating power (W);

[0052] A d : effective cross-sectional area of the air duct (m²);

[0053] ΔT: temperature difference between the hot air and the tin bar (K);

[0054] t: heating time (s);

[0055] τ: System thermal response time constant (s);

[0056] k: Equipment structure coefficient (related to the geometric parameters of the draft tube).

[0057] Application example:

[0058] When the set electromagnetic power Pe = 5 kW, the impeller speed w = 1200 rpm, and the air duct cross-sectional area Ad = 0.02 m 2 At this time, the system response time τ = 18 s is measured through experiments. When the temperature difference ΔT = 150 K and the heating time t = 300 s, substituting the above data into the above equation gives ηh ≈ 2.37.

[0059] Technical effects:

[0060] When ηh > 1.8, the hot air circulation reaches the high-efficiency energy-saving mode; the energy consumption can be optimized by adjusting the ratio of w and Pe; the exponential term reflects the dynamic response characteristics of the system and guides the setting of the preheating time.

[0061] Compared with the traditional steady-state heat transfer equation, the hot air circulation efficiency factor equation of this invention is a composite equation with a dynamic response term, integrating the electromagnetic-fluid-structure coupling effect, which significantly reduces the smelting energy consumption of this smelting furnace compared with the traditional resistance heating furnace.

[0062] The optimization process of the hot air circulation in this embodiment is as follows:

[0063] 1. Establish an objective function through the HCEF equation: max ηh;

[0064] 2. Set constraints: w ≤ 1500 rpm, ΔT ≥ 100 K;

[0065] 3. Use the genetic algorithm to solve the optimal (Pe, w) combination;

[0066] 4. Experimental verification obtains the best matching point: Pe = 4.2 kW, w = 1350 rpm.

[0067] This embodiment also provides a smelting method for an efficient energy-saving lead-free solder bar smelting furnace, including the following steps:

[0068] S1. When melting the lead-free solder bar, first slide open the sliding door 102 to open the windows of the furnace wall 1 and the heat conduction cylinder 104. Then, the staff can place the lead-free solder bar raw materials in the placement tray 106. Subsequently, push the sliding door 102 to close the window of the heat conduction cylinder 104. Then, start the electromagnetic heating coil 105 and the motor 201. The motor 201 can drive the centrifugal impeller 203 to rotate at the upper end of the heat conduction cylinder 104. The rotation of the centrifugal impeller 203 will suck the air in the heat conduction cylinder 104 and make the air enter the annular groove through the flow path on the outer surface of the centrifugal impeller 203 by rotation and be heated by the electromagnetic heating coil 105. The heated air can then be discharged back into the heat conduction cylinder 104 through the overhead area on the lower surface of the heat conduction cylinder 104 to conduct heat exchange with the lead-free solder bars placed in the placement tray 106. Moreover, it will also communicate with each other through the air vents opened on the connecting ring 107 on the outer surface of the placement tray 106, so that the heated air is sucked in again and discharged into the annular groove for secondary heating and then discharged. This process is repeated, so that the hot air can accelerate the uniform distribution of heat in the heat conduction cylinder 104, enabling the lead-free solder bars to absorb a large amount of heat in a short time, quickly reach the melting point, and accelerate the melting speed, thereby achieving the purpose of energy conservation and consumption reduction and rapid and uniform heat distribution;

[0069] S2. After reaching the melting point of the solder bar, the molten tin can fall into the storage tray 109 through the mesh holes of the placement tray 106 for centralized storage;

[0070] S3. When discharging the tin liquid in the storage disk 109, it is available for the staff to place a receiving container at the lower end of the liquid outlet pipe 301. Subsequently, the pressing plate 306 can be pressed down to drive the inserted plate 305 to slide into the guiding groove 309 of the connecting plate 303. During the process that the inserted plate 305 slides into the guiding groove 309, it will simultaneously press against one end of the spring 307. Thus, the spring 307 can apply an elastic pushing force to the inserted plate 305. The inserted plate 305 that slides into the guiding groove 309 can then be pulled out from the support rod 4, that is, the rotation restriction of the liquid outlet pipe 301 is released. Subsequently, the liquid outlet pipe 301 can automatically turn downward to make the liquid inlet 302 opened on the lower surface face the liquid outlet 110 and be connected to it. Thus, the tin liquid in the storage disk 109 can pass through the liquid inlet 302 and be discharged from the liquid outlet pipe 301. Until the required amount of tin liquid is discharged, it is available for the staff to turn the liquid outlet pipe 301 upward to make the liquid inlet 302 opened on the lower surface of the liquid outlet pipe 301 fit against the upper surface of the liquid outlet 110 and be blocked. The flattened liquid outlet pipe 301 will also block the liquid outlet 110 together. And the flattened liquid outlet pipe 301 can make the connecting plate 303 flush with the support rod 4 on the outer surface of the furnace wall 1. Thus, the inserted plate 305 that slides into the guiding groove 309 can slide into the support rod 4 again under the elastic pushing force applied by the spring 307 to lock the rotation of the liquid outlet pipe 301. That is, it realizes discharging liquid by turning downward and blocking the liquid outlet 110 to stop discharging liquid by turning upward. It enables the staff to control the discharging time of the liquid outlet pipe 301 according to needs, so as to accurately discharge the required amount of tin liquid, which helps to achieve precise control of the tin liquid consumption in the production process, avoid the situation of tin liquid waste or insufficient consumption, and is beneficial to improving product quality and production stability.

[0071] Summarize and sort out the working steps of this solution according to the above technical solution: When melting the lead-free solder bar, the sliding door 102 can be slid open first to open the windows of the furnace wall 1 and the heat conduction cylinder 104. Subsequently, the staff can place the lead-free solder bar raw materials in the placement tray 106. Then, the sliding door 102 can be pushed to close the window of the heat conduction cylinder 104. Then, the electromagnetic heating coil 105 and the motor 201 can be started. The motor 201 can drive the centrifugal impeller 203 to rotate at the upper end of the heat conduction cylinder 104. The rotation of the centrifugal impeller 203 will suck the air in the heat conduction cylinder 104 and let the air be discharged into the annular groove through the flow channel on the outer surface of the centrifugal impeller 203 by rotation and be heated by the electromagnetic heating coil 105. The heated air can be discharged into the heat conduction cylinder 104 again through the overhead area on the lower surface of the heat conduction cylinder 104 to perform heat exchange on the lead-free solder bars placed in the placement tray 106. Moreover, it will also be interconnected through the air vents opened on the connecting ring 107 on the outer surface of the placement tray 106, so that the heated air will be sucked in again and discharged into the annular groove for secondary heating and then discharged. This process is repeated, and thus the hot air can accelerate the uniform distribution of heat in the heat conduction cylinder 104. When reaching the melting point of the solder bar, the molten tin can fall into the storage tray 109 through the mesh holes of the placement tray 106 for centralized storage. When it is necessary to discharge the molten tin in the storage tray 109, the staff can place a receiving container at the lower end of the liquid outlet pipe 301. Then, the pressing plate 306 can be pressed down to drive the inserted plate 305 to slide into the guide groove 309 of the connecting plate 303. During the process of the inserted plate 305 sliding into the guide groove 309, it will press against one end of the spring 307 together. Thus, the spring 307 can exert an elastic thrust on the inserted plate 305. The inserted plate 305 that has slid into the guide groove 309 can be pulled out from the support rod 4, that is, the rotation restriction of the liquid outlet pipe 301 is released. Subsequently, the liquid outlet pipe 301 can automatically turn downward to turn the liquid inlet 302 opened on the lower surface to communicate with the liquid outlet 110. Thus, the molten tin in the storage tray 109 can be discharged from the liquid outlet pipe 301 through the liquid inlet 302. Until the required amount of molten tin is discharged, the staff can turn the liquid outlet pipe 301 upward to make the liquid inlet 302 opened on the lower surface of the liquid outlet pipe 301 fit against the upper surface of the liquid outlet 110 and be blocked. The flattened liquid outlet pipe 301 will also block the liquid outlet 110 together. Moreover, the flattened liquid outlet pipe 301 can make the connecting plate 303 flush with the support rod 4 on the outer surface of the furnace wall 1. Thus, the inserted plate 305 that has slid into the guide groove 309 can be slid into the support rod 4 again by the elastic thrust exerted by the spring 307 to lock the rotation of the liquid outlet pipe 301, that is, it realizes discharging by turning downward and can block the liquid outlet 110 to stop discharging by turning upward.

[0072] In summary, the combined use of the centrifugal impeller 203 and the electromagnetic heating coil 105 enables air to be sucked in, heated, and then discharged into the heat conduction cylinder 104 to form a hot air cycle. This cycling method accelerates the uniform distribution of heat in the heat conduction cylinder 104, allowing the lead-free solder bar to be heated more evenly, reducing local overheating or overcooling, helping to improve the quality of smelting and reduce energy consumption. When discharging the tin liquid, it can be discharged by turning the liquid outlet downward, and the liquid outlet can be blocked by turning it upward to stop the liquid discharge. This enables the staff to control the liquid discharge time of the liquid discharge pipe 301 according to needs, thereby accurately discharging the required amount of tin liquid.

[0073] Parts not involved in the present invention are the same as or can be implemented using the prior art. Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An efficient and energy-saving lead-free solder bar melting furnace, characterized in that Comprising: A furnace wall (1), an insulating cylinder (103) is fixedly installed inside the furnace wall (1), a heat-conducting cylinder (104) is fixedly installed inside the insulating cylinder (103), the heat-conducting cylinder (104) is fixedly installed on the inner ring surface of the insulating cylinder (103) through a connecting rod on the outer surface of its upper end, the heat-conducting cylinder (104) is suspended inside the insulating cylinder (103), and the heat-conducting cylinder (104) communicates with the insulating cylinder (103) through the overhead space on its lower surface. An annular groove is formed between the insulating cylinder (103) and the heat-conducting cylinder (104), and an electromagnetic heating coil (105) is fixedly installed in the annular groove between the insulating cylinder (103) and the heat-conducting cylinder (104); An insulating cover (101) is fixedly installed on the upper surface of the furnace wall (1), a wind circulation mechanism (2) is fixedly installed on the upper surface of the insulating cover (101), and the air supply end of the wind circulation mechanism (2) rotatably penetrates into the heat-conducting cylinder (104), so that the wind circulation mechanism (2) can suck the wind inside the heat-conducting cylinder (104) and let the wind be discharged into the annular groove through the flow channel on the outer surface of the wind circulation mechanism (2) by rotation and be heated by the electromagnetic heating coil (105). The heated wind is discharged into the heat-conducting cylinder (104) again through the overhead area on the lower surface of the heat-conducting cylinder (104) to heat and melt the lead-free solder bars placed in the placement tray (106). A connecting ring (107) is fixedly installed on the outer surface of the placement tray (106), and the placement tray (106) is fixedly installed inside the heat-conducting cylinder (104) through the connecting ring (107) on its outer surface, and air vents are formed in the connecting ring (107); An expansion ring (108) is fixedly installed on the outer surface of the lowermost placement tray (106), a storage tray (109) is communicated and installed on the lower surface of the expansion ring (108), the storage tray (109) is fixedly installed on the lower surface of the furnace wall (1), and the placement tray (106) is in a grid-like through state, so that the melted tin liquid can fall into the storage tray (109) through the mesh holes of the placement tray (106) for centralized storage. A liquid outlet (110) is formed at one end of the storage tray (109), and a liquid discharge mechanism (3) is rotatably installed in the liquid outlet (110), and the liquid discharge mechanism (3) can communicate with the liquid outlet (110) by flipping, so that the tin liquid stored in the storage tray (109) can be discharged through the liquid discharge mechanism (3); Windows are formed on the outer surfaces of the furnace wall (1), the insulating cylinder (103) and the heat-conducting cylinder (104), and sliding doors (102) are slidably sealed on the outer surfaces of the furnace wall (1), the insulating cylinder (103) and the heat-conducting cylinder (104), so that the sliding doors (102) can slide to seal the windows, and the three sliding doors (102) are fixedly connected together through connecting rods, so that when the sliding doors (102) are pulled and slid open, the windows of the furnace wall (1), the insulating cylinder (103) and the heat-conducting cylinder (104) can be unfolded together; The liquid discharge mechanism (3) includes a liquid outlet pipe (301) rotatably installed in the liquid outlet (110). The lower surface of the liquid outlet pipe (301) is provided with a liquid inlet (302), so that the liquid outlet pipe (301) can be rotated to turn the liquid inlet (302) to be unfolded and communicate with the liquid outlet (110), and then the tin liquid in the storage disk (109) can be discharged from the liquid outlet pipe (301) through the liquid inlet (302).

2. An efficient and energy-saving lead-free solder bar melting furnace according to claim 1, characterized in that: The sliding door (102) sliding on the outer surface of the furnace wall (1) also slides through the support rod (4), and the support rod (4) is fixedly installed on the outer surface of the furnace wall (1).

3. An efficient and energy-saving lead-free solder bar melting furnace according to claim 2, characterized in that: The air circulation mechanism (2) includes a frame plate (202) fixedly installed on the upper surface of the heat insulation cover (101). A motor (201) is fixedly installed on the upper surface of the frame plate (202). The output shaft of the motor (201) rotates through the heat conduction cylinder (104) of the furnace wall (1), and a centrifugal impeller (203) is fixedly installed on the lower surface of the output shaft of the motor (201).

4. An efficient and energy-saving lead-free solder bar melting furnace according to claim 3, characterized in that: When the centrifugal impeller (203) is driven by the motor (201) to rotate, the air pressure below the centrifugal impeller (203) will be reduced, forming a relatively low-pressure area. Then, the air below can be "sucked" towards the centrifugal impeller (203). After the air entering the centrifugal impeller (203) is accelerated, it will be blown from the flow channel of the centrifugal impeller (203) into the annular groove between the heat conduction cylinder (104) and the heat insulation cylinder (103) and heated by the electromagnetic heating coil (105).

5. An efficient and energy-saving lead-free solder bar melting furnace according to claim 4, characterized in that: A connecting plate (303) is fixedly installed on the upper surface of the liquid outlet pipe (301). A guide groove (309) is opened in the connecting plate (303). A sliding column (308) is fixedly installed in the guide groove (309). An insertion plate (305) is slidably installed on the outer surface of the sliding column (308) in the guide groove (309). In this way, after the liquid outlet pipe (301) is turned and flattened, the connecting plate (303) can be flush with one group of support rods (4) on the outer surface of the furnace wall (1). The insertion plate (305) slidably installed in the connecting plate (303) can be slid into the support rod (4), and the flattened liquid outlet pipe (301) can block the liquid outlet (110).

6. An efficient and energy-saving lead-free solder bar melting furnace according to claim 5, characterized in that: A spring (307) is sleeved on the outer surface of the sliding column (308), and the two ends of the spring (307) respectively abut between the lower surface in the guide groove (309) and the upper surface of the insertion plate (305).

7. An efficient and energy-saving lead-free solder bar melting furnace according to claim 6, characterized in that: One end of the insertion plate (305) is fixedly installed with a pressing plate (306). The pressing plate (306) slides out from the sliding groove (304). The sliding groove (304) is opened at one end of the connecting plate (303) and communicates with the guide groove (309), so that the staff can drive the insertion plate (305) to slide into the guide groove (309) by pressing the pressing plate (306).

8. A melting method for an energy-efficient lead-free solder bar melting furnace as claimed in claim 7, characterized in that: Include the following steps: S1. When melting the lead-free solder bar, first slide open the sliding door (102) to open the windows of the furnace wall (1) and the heat conduction cylinder (104). The staff places the lead-free solder bar raw materials in the placement tray (106), and then pushes the sliding door (102) to close the windows of the heat conduction cylinder (104). Start the electromagnetic heating coil (105) and the motor (201). The motor (201) drives the centrifugal impeller (203) to rotate at the upper end of the heat conduction cylinder (104). Through the rotation of the centrifugal impeller (203), the air in the heat conduction cylinder (104) is sucked in and discharged into the annular groove through the flow channel on the outer surface of the centrifugal impeller (203) by rotation and is heated by the electromagnetic heating coil (105). The heated air is discharged into the heat conduction cylinder (104) again through the overhead area on the lower surface of the heat conduction cylinder (104) to perform heat exchange on the lead-free solder bar placed in the placement tray (106). Moreover, it will also penetrate through the air vents opened on the connecting ring (107) on the outer surface of the placement tray (106), so that the heated air is sucked in again and discharged into the annular groove for secondary heating and then discharged. This process is repeated, so that the hot air can accelerate the uniform distribution of heat in the heat conduction cylinder (104), enabling the lead-free solder bar to absorb a large amount of heat in a short time, quickly reach the melting point, and accelerate the melting speed, so as to achieve the purpose of energy conservation and consumption reduction and rapid and uniform distribution of heat; S2. After reaching the melting point of the solder bar, the molten tin can fall into the storage tray (109) through the mesh holes of the placement tray (106) for centralized storage; S3. When draining the tin liquid in the storage disk (109), the staff place a receiving container at the lower end of the liquid outlet pipe (301), and then press down the pressing plate (306) to drive the inserted plate (305) to slide into the guiding groove (309) of the connecting plate (303). During the process of the inserted plate (305) sliding into the guiding groove (309), it will simultaneously press against one end of the spring (307), so that the spring (307) can exert an elastic thrust on the inserted plate (305). The inserted plate (305) that has slid into the guiding groove (309) is pulled out from the support rod (4), that is, the rotation limit of the liquid outlet pipe (301) is released. Subsequently, the liquid outlet pipe (301) can automatically turn downward so that the liquid inlet (302) opened on the lower surface is turned to communicate with the liquid outlet (110). Thus, the tin liquid in the storage disk (109) can pass through the liquid inlet (302) and be discharged from the liquid outlet pipe (301) until the required amount of tin liquid is discharged. Then the staff can turn the liquid outlet pipe (301) upward to make the liquid inlet (302) opened on the lower surface of the liquid outlet pipe (301) fit against the upper surface of the liquid outlet (110) and be blocked. The liquid outlet pipe (301) after being turned and flattened will also block the liquid outlet (110). Moreover, the flattened liquid outlet pipe (301) can make the connecting plate (303) flush with the support rod (4) on the outer surface of the furnace wall (1). Thus, the inserted plate (305) that has slid into the guiding groove (309) can slide into the support rod (4) again under the elastic thrust exerted by the spring (307) to lock the rotation of the liquid outlet pipe (301). It can achieve downward turning for liquid discharge and upward turning to block the liquid outlet (110) to stop liquid discharge, enabling the staff to control the liquid discharge time of the liquid outlet pipe (301) as needed, so as to accurately discharge the required amount of tin liquid.

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