Temperature control system and temperature control method for a reflow oven

Abstract

The application provides a temperature control system of a reflow furnace, comprising a controller, heating wires arranged in each heating cavity of the reflow furnace, and feedback thermocouples arranged in each heating cavity; the heating wires in each heating cavity are connected to the controller, and the feedback thermocouples in each heating cavity are connected to the controller; the temperature control system further comprises a blocking device arranged at the entrance of the reflow furnace and a product sensing sensor arranged at the entrance of the reflow furnace; the blocking device is connected to the controller, and the product sensing sensor is connected to the controller; the product sensing sensor is used for sensing the position of the product entering the reflow furnace; and the blocking device is used for preventing or allowing the product from entering the reflow furnace. In the mass production process, the product temperature curve is closer to the ideal curve, the product failure rate is reduced, and the production efficiency of the reflow furnace operation is improved.

Description

Technical Field

[0001] This invention relates to the field of semiconductor packaging technology, particularly to temperature control of reflow ovens for soldering, and especially to a temperature control system and method for a reflow oven. Background Technology

[0002] Existing reflow ovens, including nitrogen reflow ovens that achieve welding through upper and lower hot air and vacuum nitrogen reflow ovens, use heating wires, feedback thermocouples, and temperature controllers to control the internal cavity temperature.

[0003] like Figure 1 As shown, the reflow oven has multiple heating chambers (heating chamber 100, heating chamber 200, heating chamber 300, ...), and products 1, 2, 3, ..., N enter the reflow oven sequentially for welding. Each heating chamber is equipped with a heating wire and a feedback thermocouple, which are connected to the controller 600.

[0004] Specifically, a first feedback thermocouple 101 and a first heating wire 102 are installed in heating chamber 100; a second feedback thermocouple 201 and a second heating wire 202 are installed in heating chamber 200; a third feedback thermocouple 301 and a third heating wire 302 are installed in heating chamber 300, and so on. The first feedback thermocouple 101 and the first heating wire 102, the second feedback thermocouple 201 and the second heating wire 202, and the third feedback thermocouple 301 and the third heating wire 302 are respectively connected to the controller 600.

[0005] Taking product No. 1 as an example, the basic process for temperature control of the existing reflow oven is as follows:

[0006] Once the temperatures of each heating chamber in the reflow oven (heating chamber 100, heating chamber 200, heating chamber 300, ...) reach the set temperature, which is a fixed value, product number 1 enters heating chamber 100. Heating chamber 100 is the first heating chamber in which the product enters the reflow oven.

[0007] Product No. 1 absorbs heat and its temperature rises. Heating chamber No. 1 100 loses heat and its temperature drops. The first feedback thermocouple 101 senses the temperature drop in heating chamber No. 1 100.

[0008] The controller 600 determines that the temperature of heating chamber 100 has dropped to the lower threshold value that requires heating. The controller 600 sends a signal to the first heating wire 102 to start heating. The heat lost by heating chamber 100 is compensated, and the temperature rises.

[0009] The first feedback thermocouple 101 senses the temperature rise of heating chamber 100. The controller 600 determines that the temperature of heating chamber 100 has risen to the upper threshold value that needs to be heated. The controller 600 sends a signal to the first heating wire 102 to stop heating. The heat of heating chamber 100 returns to a stable state. The temperature of heating chamber 100 reaches a stable set value and waits for the next product cycle.

[0010] In actual production, the complex structure of the reflow oven results in the heating wire heating, thermocouple temperature feedback, and controller judgment not being real-time feedback, and there is usually a lag phenomenon.

[0011] The existence of hysteresis means that the actual temperature of the reflow oven heating chamber, even in a stable state, can only be within a temperature range. The size of this range represents the temperature control capability of the reflow oven itself. To match the oven's temperature control capability, the entry interval of continuous products must be strictly regulated. Otherwise, the temperature deviation caused by hysteresis, combined with the different product entry intervals, will result in uneven heat absorption time, ultimately leading to unqualified welded product profiles.

[0012] The welding temperature profile of a product determines that the total time the product spends in the reflow oven is a fixed value. To ensure strict adherence to the interval between each product's entry, the industry standard for reflow oven temperature control relies solely on thermocouple feedback within the cavity to control the heating chamber temperature. The frequency of product entry must be coordinated with the reflow oven's set temperature, making it a passive temperature control method. While the industry commonly uses PID calculus algorithms to calculate temperature, there is still a certain delay in terms of timeliness. Summary of the Invention

[0013] This invention provides a temperature control system and method for a reflow oven to solve the technical problem of a certain delay in the passive temperature control of reflow ovens in the prior art.

[0014] One aspect of the present invention is to provide a temperature control system for a reflow oven, the temperature control system comprising a controller, and heating wires and feedback thermocouples arranged in each heating chamber of the reflow oven.

[0015] The heating wire in each heating chamber is connected to the controller, and the feedback thermocouple in each heating chamber is connected to the controller.

[0016] The heating wire is used to heat the corresponding heating cavity; the feedback thermocouple is used to detect the temperature inside the corresponding heating cavity.

[0017] The temperature control system further includes a blocking device arranged at the inlet of the reflow oven, and a product sensing sensor arranged at the inlet of the reflow oven; the blocking device is connected to the controller, and the product sensing sensor is connected to the controller.

[0018] The product sensing sensor is used to sense the position of the product entering the reflow oven; the blocking device is used to prevent or allow the product to enter the reflow oven.

[0019] Another aspect of the present invention is to provide a temperature control method for a reflow oven, wherein the temperature control method utilizes a temperature control system for a reflow oven provided by the present invention to control the temperature of the reflow oven, and includes the following method steps:

[0020] S1. Each heating chamber of the reflux furnace is heated to the set temperature;

[0021] S2. The blocking device is activated, and the current product enters the No. 1 heating chamber of the reflow oven. At the same time, the position of the current product entering the No. 1 heating chamber of the reflow oven and the current temperature of the No. 1 heating chamber are collected. The No. 1 heating chamber is the first heating chamber in which the product enters the reflow oven.

[0022] S3. Based on the current position of the product entering the No. 1 heating chamber of the reflow oven, calculate the time it takes for the current product to reach the heating position of the No. 1 heating chamber of the reflow oven.

[0023] S4. Based on the current temperature of heating chamber 1, calculate the first time when the temperature of heating chamber 1 reaches the set temperature when the current product arrives at the heating position of heating chamber 1 in the reflow oven.

[0024] If the time it takes for the current product to reach the heating position of heating chamber 1 in the reflow oven is less than or equal to the first time, the temperature control parameters are adjusted to control the heating wire to heat heating chamber 1, so that when the current product reaches the heating position of heating chamber 1 in the reflow oven, the temperature of heating chamber 1 reaches the set temperature.

[0025] If the time it takes for the current product to reach the heating position of heating chamber 1 in the reflow oven is longer than the first time, then the heating wire is controlled to heat heating chamber 1 according to the current temperature control parameters, so that when the current product reaches the heating position of heating chamber 1 in the reflow oven, the temperature of heating chamber 1 reaches the set temperature.

[0026] In a preferred embodiment, the temperature control method further includes:

[0027] S5. When the current product reaches the heating position of heating chamber 1 in the reflow oven, the current temperature of heating chamber 1 is collected in real time.

[0028] S6. Based on the current temperature of heating chamber 1 when the current product reaches the heating position of heating chamber 1 in the reflow oven, control the heating wire to control the temperature of heating chamber 1, so that the temperature of heating chamber 1 is stabilized at the set temperature.

[0029] In a preferred embodiment, the set temperature includes a minimum set temperature threshold and a maximum set temperature threshold;

[0030] In step S6, the temperature of heating chamber 1 is stabilized between the set minimum temperature threshold and the set maximum temperature threshold.

[0031] In a preferred embodiment, the temperature control method further includes:

[0032] S7. After the current product leaves the heating position of heating chamber 1 in the reflow oven, control the heating wire to control the temperature of heating chamber 1, so that the temperature of heating chamber 1 rises back to the set temperature.

[0033] And calculate the second time after the current product leaves the heating position of heating chamber 1 in the reflow oven, and the temperature of heating chamber 1 rises back to the set temperature;

[0034] If the time it takes for the next product to reach the heating position of heating chamber 1 of the reflow oven is less than or equal to the second time, the blocking device will be closed to prevent the next product from entering heating chamber 1 of the reflow oven.

[0035] If the time it takes for the next product to reach the heating position of heating chamber 1 in the reflow oven is longer than the second time, the blocking device will be activated, and the next product will enter heating chamber 1 of the reflow oven.

[0036] In a preferred embodiment, the temperature control method further includes:

[0037] S8. When the current product enters the subsequent heating chamber of heating chamber 1, the current temperature of the subsequent heating chamber of heating chamber 1 is collected, and the time it takes for the current product to reach the heating position of the subsequent heating chamber of heating chamber 1 is calculated.

[0038] S9. Based on the current temperature of the subsequent heating chamber of heating chamber 1, calculate the third time when the temperature of the subsequent heating chamber of heating chamber 1 rises back to the set temperature when the current product arrives at the heating position of the subsequent heating chamber of heating chamber 1 in the reflow oven.

[0039] If the time it takes for the current product to reach the heating position of the subsequent heating chamber of heating chamber 1 in the reflow oven is less than or equal to the third time, then the temperature control parameters are adjusted to control the heating wire to heat the subsequent heating chamber of heating chamber 1, so that when the current product reaches the heating position of the subsequent heating chamber of heating chamber 1 in the reflow oven, the temperature of the subsequent heating chamber of heating chamber 1 reaches the set temperature.

[0040] If the time it takes for the current product to reach the heating position of the subsequent heating chamber of heating chamber 1 in the reflow oven is longer than the third time, then the heating wire is controlled to heat the subsequent heating chamber of heating chamber 1 according to the current temperature control parameters, so that when the current product reaches the heating position of the subsequent heating chamber of heating chamber 1 in the reflow oven, the temperature of the subsequent heating chamber of heating chamber 1 reaches the set temperature.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] This invention provides a temperature control system and method for a reflow oven. A blocking device is designed at the reflow oven inlet to control the frequency of product entry. Simultaneously, a signal is sent to the controller. Based on the product arrival signal, the controller calculates the time it takes for the product to reach the heating position within the heating chamber. Using the product arrival time, the current temperature within the heating chamber, and the controller's control parameters, the controller calculates whether the temperature within the heating chamber can stabilize at the set temperature before the product reaches the heating position. As the product flows through the heating position within the heating chamber, the controller ensures that the temperature within the heating chamber remains stable within a certain threshold during the heat absorption process.

[0043] The present invention provides a temperature control system and temperature control method for a reflow oven. The blocking device controls the time when the product enters the oven based on the judgment result of the controller, while ensuring that the product welding is satisfied, so as to maximize the comprehensive thermal performance of the heating chamber and avoid the actual curve of the product not meeting the standard.

[0044] This invention provides a temperature control system and method for a reflow oven. It integrates the product sensing sensor and blocking device at the reflow oven inlet into the temperature control, thereby automatically controlling the entire temperature control system. Based on the reflow oven temperature setting that satisfies the welding curve of a single product, the controller is notified of the position of products continuously entering the heating chamber. The controller combines the product in the heating chamber, the heating wire power, and the sensing temperature of the feedback thermocouple to comprehensively determine the heating wire output power and time, ensuring that the predetermined product temperature is reached at each position in the heating chamber before each product reaches its heating position. If the product entry frequency exceeds the equipment's allowable frequency, the blocking device at the inlet can prevent (delay) the product entry time, controlling the time interval.

[0045] The present invention provides a temperature control system and method for a reflow oven, which realizes intelligent linkage between the temperature of the heating chamber and the start and stop of the heating wire, and adjusts the temperature in a timely manner according to the quantity of products entering the heating oven, thereby saving energy consumption.

[0046] The present invention provides a temperature control system and temperature control method for a reflow oven, which makes the product temperature curve closer to the ideal curve during mass production, reduces the product defect rate, and improves the production efficiency of the reflow oven. Attached Figure Description

[0047] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0048] Figure 1 This is a schematic diagram of the temperature control of an existing reflux furnace.

[0049] Figure 2 This is a schematic diagram of the process by which product No. 1 of the present invention enters heating chamber No. 1.

[0050] Figure 3 This is a schematic diagram of the process by which product No. 1 of the present invention enters heating chamber No. 2. Detailed Implementation

[0051] To make the above and other features and advantages of the present invention clearer, the invention will be further described below with reference to the accompanying drawings. It should be understood that the specific embodiments given herein are for the purpose of explanation to those skilled in the art and are exemplary only, not restrictive.

[0052] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention 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 invention.

[0053] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0054] Combination Figure 2 and Figure 3According to an embodiment of the present invention, a temperature control system for a reflow oven is provided, including a controller 600, a blocking device 400 arranged at the inlet of the reflow oven, a product sensing sensor 500 arranged at the inlet of the reflow oven, and heating wires and feedback thermocouples arranged in each heating chamber of the reflow oven.

[0055] The reflow oven has multiple heating chambers. In this embodiment, the reflow oven is exemplarily described by three heating chambers, namely heating chamber 100, heating chamber 200, and heating chamber 300.

[0056] A first feedback thermocouple 101 and a first heating wire 102 are installed in heating chamber 100; a second feedback thermocouple 201 and a second heating wire 202 are installed in heating chamber 200; and a third feedback thermocouple 301 and a third heating wire 302 are installed in heating chamber 300.

[0057] The heating wire in each heating chamber is connected to the controller 600, and the feedback thermocouple in each heating chamber is connected to the controller 600.

[0058] In this embodiment, the first feedback thermocouple 101 and the first heating wire 102, the second feedback thermocouple 201 and the second heating wire 202, and the third feedback thermocouple 301 and the third heating wire 302 are respectively connected to the controller 600.

[0059] A heating wire is used to heat the corresponding heating chamber. A feedback thermocouple is used to detect the temperature inside the corresponding heating chamber. Taking heating chamber 100 as an example, the first heating wire 102 is used to heat heating chamber 100, and the first feedback thermocouple 101 is used to detect the temperature inside heating chamber 100.

[0060] The blocking device 400 is connected to the controller 600, and the product sensing sensor 500 is also connected to the controller 600. The product sensing sensor 500 is used to sense the position of the product entering the reflow oven. The blocking device 400 is used to prevent or allow the product to enter the reflow oven.

[0061] Combination Figure 2 According to an embodiment of the present invention, a temperature control method for a reflow oven is provided, which utilizes a temperature control system for the reflow oven to control the temperature of the reflow oven, comprising the following steps:

[0062] Step S1: Each heating chamber of the reflux furnace is heated to the set temperature.

[0063] Specifically, before the product enters the reflow oven, the controller 600 controls the heating wires (first heating wire 102, second heating wire 202, and third heating wire 302) of each heating chamber (heating chamber 100, heating chamber 200, and heating chamber 300) to heat up, so that each heating chamber of the reflow oven is heated to the set temperature.

[0064] Step S2: The blocking device 400 is activated, and the current product enters the No. 1 heating chamber 100 of the reflow oven. At the same time, the position of the current product entering the No. 1 heating chamber 100 of the reflow oven and the current temperature of the No. 1 heating chamber 100 are collected. The No. 1 heating chamber 100 of this invention is the first heating chamber in which the product enters the reflow oven.

[0065] In the following embodiments, product No. 1 is used as an example for explanation. Before product No. 1 enters the reflow oven, the temperature of each heating chamber in the reflow oven has been heated to the set temperature.

[0066] The controller 600 controls the blocking device 400 to open, and the current product (product No. 1) enters the No. 1 heating chamber 100 of the reflow oven.

[0067] The product sensing sensor 500 collects the position of the current product (product 1) entering the No. 1 heating chamber 100 of the reflow oven. As product 1 absorbs heat after entering the No. 1 heating chamber 100 of the reflow oven, the temperature of the No. 1 heating chamber 100 drops, and the first feedback thermocouple 101 collects the current temperature of the No. 1 heating chamber 100.

[0068] The product sensing sensor 500 sends the position of the current product (product 1) entering the No. 1 heating chamber 100 of the reflow oven to the controller 600. The first feedback thermocouple 101 sends the current temperature of the No. 1 heating chamber 100 to the controller 600.

[0069] Step S3: Based on the current product's position in heating chamber 100 of the reflow oven, calculate the time it takes for the current product to reach the heating position W of heating chamber 100 of the reflow oven.

[0070] Specifically, since the positions of each heating chamber in the reflow oven are fixed, and the chain speed of the product conveying along the product conveying direction is fixed, the controller 600 calculates the time it takes for the current product (product 1) to reach the heating position W of the reflow oven's heating chamber 100 based on the current product's (product 1's) position upon entering the reflow oven's heating chamber 100. That is, it calculates the time it takes for the current product (product 1) to travel from its initial position in the reflow oven's heating chamber 100 to its final heating position W.

[0071] Step S4: Based on the current temperature of heating chamber 1, calculate the first time when the temperature of heating chamber 1 reaches the set temperature when the current product arrives at the heating position of heating chamber 1 in the reflow oven.

[0072] Specifically, the controller 600 calculates the time (first time) when the temperature of the heating chamber 100 reaches the set temperature when the current product (product 1) enters the heating position W of the heating chamber 100 of the reflow oven, based on the current temperature of the current product (product 1) entering the heating chamber 100 of the reflow oven.

[0073] If the time it takes for the current product (product 1) to reach the heating position W of the heating chamber 100 of the reflow oven is less than or equal to the first time, the controller 600 adjusts the temperature control parameters to control the heating wire (first heating wire 102) to heat the heating chamber 100, so that when the current product (product 1) reaches the heating position W of the heating chamber 100 of the reflow oven, the temperature of the heating chamber 100 reaches the set temperature.

[0074] If the time taken for the current product (product 1) to reach the heating position W of the No. 1 heating chamber 100 of the reflow oven is longer than the first time, then the controller 600 controls the heating wire (first heating wire 102) to heat the No. 1 heating chamber 100 according to the current temperature control parameters, so that when the current product (product 1) reaches the heating position W of the No. 1 heating chamber 100 of the reflow oven, the temperature of the No. 1 heating chamber 100 reaches the set temperature.

[0075] The controller 600 of this invention can be composed of multiple single temperature controllers, or can use a PLC + temperature control module, or a host computer + temperature control module. In specific embodiments, the temperature control determination algorithm and parameter adjustment algorithm can be implemented using common PID control algorithms, deep learning algorithms, or other types of control algorithms. Those skilled in the art can adapt the specific algorithm implementation process according to the technical solution disclosed in this invention; it will not be elaborated further in the embodiments.

[0076] Step S5: When the current product reaches the heating position W of heating chamber 100 of the reflow oven, the current temperature of heating chamber 100 is collected in real time.

[0077] Specifically, when the current product (product No. 1) reaches the heating position W of heating chamber 100 of the reflow oven, the current temperature of heating chamber 100 is collected in real time by the first feedback thermocouple 101 and sent to the controller 600.

[0078] Step S6: Based on the current temperature of heating chamber 100 when the current product reaches the heating position of heating chamber 1 in the reflow oven, control the heating wire to control the temperature of heating chamber 100 so that the temperature of heating chamber 100 is stabilized at the set temperature.

[0079] Specifically, as product 1 is conveyed along the product conveying direction, it continuously absorbs heat, causing the temperature of heating chamber 100 to drop. The controller 600, based on the current temperature of heating chamber 100 when the current product (product 1) reaches the heating position W of heating chamber 100 in the reflow oven, controls the heating wire (first heating wire 102) to control the temperature of heating chamber 100, stabilizing the temperature of heating chamber 100 at the set temperature.

[0080] In a preferred embodiment, setting the temperature includes setting a minimum temperature threshold and setting a maximum temperature threshold.

[0081] The temperature of heating chamber 100 is stabilized between the set minimum temperature threshold and the set maximum temperature threshold. That is, when the current product (product 1) arrives at the heating position W of heating chamber 100 in the reflow oven, the current temperature of heating chamber 100 is controlled to be neither lower than the set minimum temperature threshold nor higher than the set maximum temperature threshold.

[0082] Step S7: After the current product leaves the heating position of heating chamber 100 of the reflow oven, control the heating wire to control the temperature of heating chamber 100, so that the temperature of heating chamber 100 rises back to the set temperature; and calculate the second time when the temperature of heating chamber 100 rises back to the set temperature after the current product leaves the heating position of heating chamber 100 of the reflow oven.

[0083] Specifically, as product 1 is conveyed along the product conveying direction, it continuously absorbs heat, causing the temperature of heating chamber 100 to drop. After the current product (product 1) leaves the heating position W of heating chamber 100 in the reflow oven, controller 600 controls (first heating wire 102) to control the temperature of heating chamber 100, so that the temperature of heating chamber 100 rises back to the set temperature.

[0084] And calculate the second time after the current product (product No. 1) leaves the heating position W of heating chamber 100 1 of the reflow oven, and the temperature of heating chamber 100 1 rises back to the set temperature.

[0085] If the time it takes for the next product to reach the heating position W of heating chamber 100 in the reflow oven is less than or equal to the second time, the blocking device 400 will be closed to prevent the next product from being returned to heating chamber 1 of the reflow oven.

[0086] In this invention, "next product" refers to the product following the current product. In this embodiment, the current product is product number 1, and the next product is product number 2.

[0087] Specifically, the product sensing sensor 500 collects the position of the next product (product 2) entering the No. 1 heating chamber 100 of the reflow oven and sends the position of the next product (product 2) entering the No. 1 heating chamber 100 of the reflow oven to the controller 600.

[0088] The controller 600 calculates the time it takes for the next product (product 2) to reach the heating position W of the first heating chamber 100 of the reflow oven based on the position of the next product (product 2) entering the first heating chamber 100. In other words, it calculates the time it takes for the next product (product 2) to travel from its initial position entering the first heating chamber 100 of the reflow oven to its final heating position W.

[0089] If the time it takes for the next product (product number 2) to reach the heating position W of the first heating chamber 100 of the reflow oven is less than or equal to the second time, the controller 600 controls the blocking device 400 to close, preventing the next product (product number 2) from entering the first heating chamber 100 of the reflow oven.

[0090] If the time taken for the next product (product number 2) to reach the heating position W of the first heating chamber 100 of the reflow oven is longer than the second time, the controller 600 and the blocking device 400 will be activated, and the next product (product number 2) will enter the first heating chamber 100 of the reflow oven.

[0091] Step S8: When the current product enters the subsequent heating chamber of heating chamber 1, the current temperature of the subsequent heating chamber of heating chamber 1 is collected, and the time it takes for the current product to reach the heating position of the subsequent heating chamber of heating chamber 1 is calculated.

[0092] The subsequent heating chamber in this invention refers to the heating chamber following the previous heating chamber along the product conveying direction. In this embodiment, the subsequent heating chamber of heating chamber 100 is heating chamber 200.

[0093] like Figure 3 As shown, specifically, when the current product (product 1) enters the subsequent heating chamber (heating chamber 200) of heating chamber 100, the second feedback thermocouple 201 collects the current temperature of the current product (product 1) entering the subsequent heating chamber (heating chamber 200) of heating chamber 100.

[0094] Furthermore, the controller 600 calculates the time it takes for the current product (product 1) to reach the heating position W of the subsequent heating chamber (heating chamber 200) of heating chamber 100.

[0095] Step S9: Based on the current temperature of the subsequent heating chamber (heating chamber 200) of heating chamber 100, calculate the third time when the temperature of the subsequent heating chamber (heating chamber 200) of heating chamber 100 of heating chamber 100 rises back to the set temperature when the current product (product 1) arrives at the heating position W of the subsequent heating chamber (heating chamber 200) of heating chamber 100 of reflow oven.

[0096] Specifically, the controller 600 calculates the third time when the temperature of the current product (product 1) reaches the heating position W of the subsequent heating chamber (heating chamber 200) of the reflow oven, based on the current temperature of the current product (product 1) entering the subsequent heating chamber (heating chamber 200) of heating chamber 100.

[0097] If the time it takes for the current product (product 1) to reach the heating position W of the subsequent heating chamber (heating chamber 200) of heating chamber 100 in the reflow oven is less than or equal to the third time, then the controller 600 adjusts the temperature control parameters to control the heating wire (second heating wire 202) to heat the subsequent heating chamber (heating chamber 200) of heating chamber 100, so that when the current product (product 1) reaches the heating position W of the subsequent heating chamber (heating chamber 200) of heating chamber 100 in the reflow oven, the temperature of the subsequent heating chamber (heating chamber 200) of heating chamber 100 reaches the set temperature.

[0098] If the time taken for the current product (product 1) to reach the heating position W of the subsequent heating chamber (heating chamber 200) of heating chamber 100 in the reflow oven is greater than a third time, then the controller 600 controls the heating wire (second heating wire 202) to heat the subsequent heating chamber (heating chamber 200) of heating chamber 100 according to the current temperature control parameters, so that when the current product (product 1) reaches the heating position W of the subsequent heating chamber (heating chamber 200) of heating chamber 100 in the reflow oven, the temperature of the subsequent heating chamber (heating chamber 200) of heating chamber 100 reaches the set temperature.

[0099] Afterwards, the temperature control process of product 1 entering the subsequent heating chamber (heating chamber 300) of heating chamber 200 and the subsequent temperature control process along the product conveying direction is the same as the temperature control process of product 1 entering the subsequent heating chamber (heating chamber 200) of heating chamber 100, and will not be described again here.

[0100] The temperature control process for products No. 2, No. 3, ..., No. N is the same as that for product No. 1, and will not be repeated here.

[0101] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A temperature control method for a reflux furnace, characterized in that, The temperature control method utilizes a temperature control system to control the temperature of the reflow oven. The temperature control system includes a controller, and heating wires and feedback thermocouples arranged in each heating chamber of the reflow oven. The heating wires in each heating chamber are connected to the controller, and the feedback thermocouples in each heating chamber are also connected to the controller. The heating wires are used to heat the corresponding heating chamber; the feedback thermocouples are used to detect the temperature in the corresponding heating chamber. The temperature control system further includes a blocking device arranged at the inlet of the reflow oven and a product sensing sensor arranged at the inlet of the reflow oven; the blocking device is connected to the controller, and the product sensing sensor is connected to the controller; the product sensing sensor is used to sense the position of the product entering the reflow oven; the blocking device is used to prevent or allow the product to enter the reflow oven. The temperature control method includes the following steps: S1. Each heating chamber of the reflux furnace is heated to the set temperature; S2. The blocking device is activated, and the current product enters the No. 1 heating chamber of the reflow oven. At the same time, the position of the current product entering the No. 1 heating chamber of the reflow oven and the current temperature of the No. 1 heating chamber are collected. The No. 1 heating chamber is the first heating chamber in which the product enters the reflow oven. S3. Based on the current position of the product entering the No. 1 heating chamber of the reflow oven, calculate the time it takes for the current product to reach the heating position of the No. 1 heating chamber of the reflow oven. S4. Based on the current temperature of heating chamber 1, calculate the first time when the temperature of heating chamber 1 reaches the set temperature when the current product arrives at the heating position of heating chamber 1 in the reflow oven. If the time it takes for the current product to reach the heating position of heating chamber 1 in the reflow oven is less than or equal to the first time, the temperature control parameters are adjusted to control the heating wire to heat heating chamber 1, so that when the current product reaches the heating position of heating chamber 1 in the reflow oven, the temperature of heating chamber 1 reaches the set temperature. If the time it takes for the current product to reach the heating position of heating chamber 1 in the reflow oven is longer than the first time, then the heating wire is controlled to heat heating chamber 1 according to the current temperature control parameters, so that when the current product reaches the heating position of heating chamber 1 in the reflow oven, the temperature of heating chamber 1 reaches the set temperature.

2. The temperature control method according to claim 1, characterized in that, The temperature control method further includes: S5. When the current product reaches the heating position of heating chamber 1 in the reflow oven, the current temperature of heating chamber 1 is collected in real time. S6. Based on the current temperature of heating chamber 1 when the current product reaches the heating position of heating chamber 1 in the reflow oven, control the heating wire to control the temperature of heating chamber 1, so that the temperature of heating chamber 1 is stabilized at the set temperature.

3. The temperature control method according to claim 2, characterized in that, The set temperature includes a minimum set temperature threshold and a maximum set temperature threshold; In step S6, the temperature of heating chamber 1 is stabilized between the set minimum temperature threshold and the set maximum temperature threshold.

4. The temperature control method according to claim 2, characterized in that, The temperature control method further includes: S7. After the current product leaves the heating position of heating chamber 1 in the reflow oven, control the heating wire to control the temperature of heating chamber 1, so that the temperature of heating chamber 1 rises back to the set temperature. And calculate the second time after the current product leaves the heating position of heating chamber 1 in the reflow oven, and the temperature of heating chamber 1 rises back to the set temperature; If the time it takes for the next product to reach the heating position of heating chamber 1 of the reflow oven is less than or equal to the second time, the blocking device will be closed to prevent the next product from entering heating chamber 1 of the reflow oven. If the time it takes for the next product to reach the heating position of heating chamber 1 in the reflow oven is longer than the second time, the blocking device will be activated, and the next product will enter heating chamber 1 of the reflow oven.

5. The temperature control method according to claim 4, characterized in that, The temperature control method further includes: S8. When the current product enters the subsequent heating chamber of heating chamber 1, the current temperature of the subsequent heating chamber of heating chamber 1 is collected, and the time it takes for the current product to reach the heating position of the subsequent heating chamber of heating chamber 1 is calculated. S9. Based on the current temperature of the subsequent heating chamber of heating chamber 1, calculate the third time when the temperature of the subsequent heating chamber of heating chamber 1 rises back to the set temperature when the current product arrives at the heating position of the subsequent heating chamber of heating chamber 1 in the reflow oven. If the time it takes for the current product to reach the heating position of the subsequent heating chamber of heating chamber 1 in the reflow oven is less than or equal to the third time, then the temperature control parameters are adjusted to control the heating wire to heat the subsequent heating chamber of heating chamber 1, so that when the current product reaches the heating position of the subsequent heating chamber of heating chamber 1 in the reflow oven, the temperature of the subsequent heating chamber of heating chamber 1 reaches the set temperature. If the time it takes for the current product to reach the heating position of the subsequent heating chamber of heating chamber 1 in the reflow oven is longer than the third time, then the heating wire is controlled to heat the subsequent heating chamber of heating chamber 1 according to the current temperature control parameters, so that when the current product reaches the heating position of the subsequent heating chamber of heating chamber 1 in the reflow oven, the temperature of the subsequent heating chamber of heating chamber 1 reaches the set temperature.

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