Technical Field

[0001] The present application relates to a processing furnace, particularly to a processing furnace including a heating zone.

Background

[0002] A furnace chamber of certain processing furnaces includes a heating zone and a cooling zone, and a processing element to be processed is conveyed by a conveying device through the heating zone and the cooling zone in the furnace chamber in this order to complete the processing process of heating and cooling processing. There may be different requirements on heating processing temperatures for different processing elements. In general, it is necessary to adjust the temperature in the furnace chamber to a predetermined temperature before processing the processing elements.

Summary

[0003] It is at least one object of the present application to provide a processing furnace capable of conveniently regulating the temperature in a furnace chamber, the processing furnace including: a furnace chamber including a heating zone and a cooling zone; at least one heat exchange device including a heat exchange channel, the heat exchange channel being disposed within the heating zone, the heat exchange channel having a heat exchange channel inlet and a heat exchange channel outlet, the heat exchange channel inlet and the heat exchange channel outlet being in fluid communication with the outside, such that an outside air is able to enter the heat exchange channel from the heat exchange channel inlet, flow through the heat exchange channel and then flow out from the heat exchange channel outlet; wherein the heat exchange device is configured to enable heat exchange between a gas in the heating zone and the air in the heat exchange channel.

[0004] In accordance with the foregoing, the heat exchange device includes a heat exchange tube including a tube wall, the heat exchange channel being enclosed by the tube wall, and the tube wall being in contact with a gas in the heating zone such that the gas in the heating zone and the air in the heat exchange channel exchange heat through the tube wall.

[0005] In accordance with the foregoing, the furnace chamber includes a gas internal circulation channel, the furnace chamber configured to cause the gas in the furnace chamber to flow in the gas internal circulation channel, the heat exchange tube disposed in the gas internal circulation channel to exchange heat with the gas in the gas internal circulation channel.

[0006] In accordance with the foregoing, the furnace chamber includes an upper furnace chamber and a lower furnace chamber, the heat exchange tube being disposed in the upper furnace chamber.

[0007] In accordance with the foregoing, the gas internal circulation channel includes an upper suction channel, an upper exhaust channel, a lower suction channel, and a lower exhaust channel, the gas internal circulation channel including an upper suction channel, an upper exhaust channel, a lower suction channel and a lower exhaust channel, the upper suction channel and the upper exhaust channel disposed in the upper furnace chamber, and the lower suction channel and the lower exhaust channel disposed in the lower furnace chamber, wherein the heat exchange tube is disposed in the upper suction channel.

[0008] hi accordance with the foregoing, the processing furnace further includes an air discharge duct, the heat exchange channel outlet of each of the heat exchange devices being connected to the air discharge duct to enable the air to be discharged together after confluence after the heat exchange is completed.

[0009] In accordance with the foregoing, the heat exchange device further includes a fan configured to drive the air to flow in the heat exchange channel to enable air flowing in from the heat exchange channel inlet to flow out from the heat exchange channel outlet.

[0010] In accordance with the foregoing, the heat exchange device further includes a plurality of fins disposed within the heat exchange tube and in connection with the tube wall. [0011] In accordance with the foregoing, the heat exchange tube includes a first side tube and a second side tube disposed side by side, one end of the first side tube being in communication with one end of the second side tube, the other ends forming the heat exchange channel inlet and the heat exchange channel outlet, respectively, wherein the fins are disposed in the first side tube and the second side tube respectively in directions in which the first side tube and the second side tube extend. [0012] In accordance with the foregoing, the heating zone includes a plurality of heating subregions, wherein one of the heat exchange devices is provided in each heating subregion. [0013] Other objects and advantages of the present application will be apparent from the description of the present application hereinafter with reference to the accompanying drawings, and may help with a full understanding of the present application.

Brief Description of the Drawings

[0014] Fig. 1 is a schematic view of the principle of a processing furnace of the present application;

[0015] Figs. 2A and 2B are perspective views at two angles of one example of a heating zone of Fig. 1;

[0016] Fig. 2C is a top view of Fig. 2A;

[0017] Fig. 3A is a cross-sectional view of the heating zone shown in Fig. 2C along line A- A;

[0018] Fig. 3B is a cross-sectional view of the heating zone shown in Fig. 2C along line B- B;

[0019] Fig. 3C is a perspective view of an upper divider in Fig. 2C;

[0020] Fig. 4A is a perspective view of a heat exchange device in Fig. 2A;

[0021] Fig. 4B is an exploded view of Fig. 4C;

[0022] Fig. 4C is a top view of a heat exchange tube of Fig. 4B; [0023] Fig. 4D is a cross-sectional view of Fig. 4C along line C-C;

[0024] Fig. 4E is a cross-sectional view of Fig. 4C along line D-D.

Detailed Description

[0025] Various specific embodiments of the present application will be described below with reference to the attached drawings that form a part of the present specification. It should be understood that while terms denoting orientation, such as “front,” “rear,” “upper,” “lower,” “left,” “right,” “top,” “bottom,” “inside,” “outside,” etc., are used in the present application to describe various exemplary structural parts and elements of the present application, these terms are used herein for convenience of illustration only and are determined based on the exemplary orientations shown in the attached drawings. Since the examples disclosed in the present application may be disposed in different orientations, these terms denoting orientation are for illustrative purposes only and should not be considered as limiting.

[0026] Fig. 1 is a schematic view of the principle of a processing furnace 100 of the present application. In the production of printed circuit boards, electronic elements are typically mounted to circuit boards using a process called “reflow soldering.” In a typical reflow soldering process, a soldering paste (e.g., tin paste) is deposited into a selected area on a circuit board and a wire of one or more electronic elements is inserted into the deposited soldering paste. The circuit board then passes through a reflow furnace in which the soldering paste refluxes in a heating zone (i.e., is heated to a melting or reflux temperature) and then cools in a cooling zone to form a soldering point that electrically and mechanically connect the wires of the electronic elements to the circuit board. As used herein, the term “circuit board” comprises a substrate assembly of any type of electronic element, such as comprises a wafer substrate. In the present example, detailed description will be made using an example in which the processing furnace 100 is a reflow furnace. It will be appreciated by those skilled in the art that in other examples, the processing furnace may also be a processing furnace such as a sintering furnace, as long as a heating zone is included.

[0027] As shown in Fig. 1, the processing furnace 100 has a furnace chamber 110 that includes a heating zone 101 and a cooling zone 105, and the heating zone 101 and the cooling zone 105 are disposed side by side along a length direction L of the furnace chamber 110. A heating element (see heating element 211 in Fig. 2A) is provided in the heating zone 101 to enable a gas in the heating zone 101 to be heated. Similarly, a cooling element (not shown in the drawings) is provided in the cooling zone 105 to enable a gas in the cooling zone 105 to be cooled.

[0028] The processing furnace 100 further includes a conveying channel 112 and a conveying device 118. The furnace chamber 110 includes an upper furnace chamber 102 and a lower furnace chamber 104 disposed opposite to each other. The conveying channel 112 is disposed between the upper furnace chamber 102 and the lower furnace chamber 104 of the furnace chamber 110 and extends in the length direction L of the furnace chamber 110 through the heating zone 101 and the cooling zone 105 in this order. The conveying device 118 is used to transport a processing element 103 to be processed along the conveying channel 112 through the heating zone 101 and the cooling zone 105 of the furnace chamber 110, such as feeding the processing element 103 to be processed from the left end of the conveying channel 112 into the furnace chamber 110, passing through the heating zone 101 and the cooling zone 105 in turn in the length direction L (i.e., the extending direction of the conveying channel 112) of the furnace chamber 110 for soldering, and then conveying the processing element 103 that has been processed out from the right end of the conveying channel 112.

[0029] The processing furnace 100 further includes a pair of blocking boxes 108 disposed on the left and right ends of the furnace chamber 110, respectively, that is, the outside of the heating zone 101 and the cooling zone 105. When the processing furnace 100 uses a substantially inert gas (such as nitrogen) as the working gas, the pair of blocking boxes 108 are used to block the heating zone 101 and the cooling zone 105 in the furnace chamber 110 from communicating with the external environment so as to prevent air in the external environment from affecting the soldering quality.

[0030] The processing furnace 100 also includes a barrier exhaust zone 109 disposed between the heating zone 101 and the cooling zone 105. The barrier exhaust zone 109 may draw or exhaust gas from the furnace chamber 110, thereby impeding or reducing volatile pollutant containing gas from the heating zone 101 from entering the cooling zone 105, and as an insulation zone isolating the high temperature heating zone 101 from the low temperature cooling zone 105. [0031] In the present example, the heating zone 101 includes a plurality of heating subregions 115 disposed side by side, each of which is independently provided with a heating element (see heating element 211 in Fig. 2A) to heat the gas in each of the heating subregions 115 to a different temperature. Specifically, the temperature of gas in each heating subregion 115 gradually increases from left to right. That is, the gas temperature in the heating subregion 115 proximate the left end of the furnace chamber 110 is the lowest and the gas temperature in the heating subregion 115 proximate the barrier exhaust zone 109 is the highest.

[0032] Similarly, the cooling zone 105 also includes a plurality of cooling subregions 117 disposed side by side, each of which is independently provided with a cooling element (not shown) to cool gas in each of the cooling subregions 117 to a different temperature. Specifically, the temperature of gas in each cooling subregion 117 gradually decreases from left to right. That is, the gas temperature in the cooling subregion 117 proximate the barrier exhaust zone 109 is the highest and the gas temperature in the cooling subregion 117 proximate the right end of the furnace chamber 110 is the lowest.

[0033] As such, when the processing element 103 to be processed is fed by the conveying device 118 from the left end of the conveying channel 112 into the furnace chamber 110, the processing element 103 is first heated in each heating subregions 115 so that a soldering flux in the soldering paste on the processing element 103 is gradually vaporized, and until after reaching the rightmost heating subregion 115, the soldering flux is substantially completely vaporized. The processing element 103 is then progressively cooled in the various cooling subregions 117 to cause the soldering paste on the processing element 103 to be cooled and cured to form a soldering point, thereby connecting the electronic element on the circuit board to complete the processing process. Finally, the processing element 103 is conveyed out of the furnace chamber 110 from the right end of the conveying channel 112 by the conveying device 118.

[0034] The processing furnace 100 also includes a plurality of heat exchange devices 120 for heat exchange between the gas in the furnace chamber 110 (hereinafter referred to as the furnace chamber gas) and external air to cool the heated furnace chamber gas in the furnace chamber 110. In particular, the heat exchange device 120 has a heat exchange channel 123, and the heat exchange channel 123 has a heat exchange channel inlet 121 and a heat exchange channel outlet 122. The heat exchange channel 123 is disposed inside the furnace chamber 110 to enable the external air flowing through the heat exchange channel 123 to exchange heat with the furnace chamber gas. The heat exchange channel inlet 121 is in communication with the outside to enable air from the outside to enter the heat exchange channel 123 from the heat exchange channel inlet 121. The heat exchange channel outlet 122 is connected to the air discharge duct 125 to enable air flowing through the heat exchange channel 123 and exchanging heat to be expelled together after confluence in the air discharge duct 125. In the present example, each heating subregion 115 is provided with a heat exchange device 120 such that the gas within each heating subregion 115 is capable of heat exchange with the external air by the heat exchange device 120. As one example, each heat exchange device 120 is disposed in a corresponding heating subregion 115 of the upper furnace chamber 102.

[0035] Figs. 2A to 2C show a specific structure of one example of the heating zone 101 for illustrating the external structure of the heating zone 101. Here, Figs. 2A and 2B show a perspective view of three heating subregions 11 in the heating zone 101 at two angles, and Fig. 2C shows a top view of Fig. 2A. As shown in Figs. 2Ato 2C, the three heating subregions 115 are provided side by side along the length direction L of the furnace chamber 110 and are supported by a bracket 216, with each heating subregion 115 having a substantially identical structure. It will be appreciated by those skilled in the art that although the heating zone 101 shown includes three heating subregions 115, in other examples, the heating zone 101 may include more or less heating subregions 115. The conveying channel 112 traverses the three heating subregions 115 and forms an inlet end 206 at a front end of the heating zone 101 and an outlet end 207 at a rear end of the heating zone 101. The processing element 103 is capable of being conveyed by the conveying device 118 from the inlet end 206 into the conveying channel 112, and then conveyed out from the outlet end 207 after passing through the three heating subregions 115 in turn.

[0036] Each heating subregion 115 includes a respective heating element 211 and a pair of fans 213 disposed in the upper furnace chamber 102 and the lower furnace chamber 104, respectively. The heating element 211 is a heating rod that is inserted to the right from the left side of a width direction W of the furnace chamber 110 (e.g., the left side in Fig. 2A) into each heating subregion 115 to heat the furnace chamber gas in each heating subregion 115 respectively. In the present example, heating elements 211 are provided in both the upper furnace chamber 102 and the lower furnace chamber 104, and it is understood by those skilled in the art that the heating element 211 can also be provided only in either the upper furnace chamber 102 or the lower furnace chamber 104. The pair of fans 213 are respectively disposed at the top and bottom of each heating subregion 115 to drive the furnace chamber gas flow inside each heating subregion 115 to form respective gas internal circulation channels (see gas internal circulation channels 335 in Figs. 3A and 3B). The furnace chamber gas in each heating subregion 115 circulates through the respective gas internal circulation channel 335 to enable uniform heating of the furnace chamber gas by the heating element 211.

[0037] The heat exchange device 120 is inserted to the left into each heating subregion 115 from the right side of the width direction W (e.g., the right side in Fig. 2A) of the furnace chamber 110. The heat exchange channel 123 of the heat exchange device 120 extends inside the heating subregion 115 for heat exchange with the furnace chamber gas in the heating subregion 115. The heat exchange channel inlet 121 and the heat exchange channel outlet 122 of the heat exchange device 120 protrude outside the heating subregion 115 and are in communication with the outside. In the present example, the heat exchange device 120 further includes a centrifugal fan 214 disposed at the heat exchange channel inlet 121. Under the drive of the centrifugal fan 214, outside air enters the heat exchange channel 123 from the heat exchange channel inlet 121, flows through the heat exchange channel 123 for heat exchange with the furnace chamber gas in the heating subregion 115, then flows out from the heat exchange channel outlet 122 and is discharged after confluence in the air discharge duct 125. In the present example, the heat exchange device 120 of the present application is capable of cooling the gas temperature in the heating subregion 115 and heating the air flowing through the heat exchange channel 123, so the air discharged from the air discharge duct 215 may have a higher temperature. Those skilled in the art may dissipate heat or cool the air discharged from the air discharge duct 215 before discharging to the outside according to actual needs.

[0038] Figs. 3A and 3B show cross-sectional views of the heating zone 101 in Figs. 2A to 2C along the line A- A and along the line B-B for illustrating the internal structure of the heating zone 101, and Fig. 3C shows the structure of one example of an upper divider 341. For ease of display, only one pair of tracks of the conveying device 118 are shown in Figs. 3 A and 3B, and other components of the conveying device 118 are concealed.

[0039] As shown in Figs. 3 A to 3C, the tracks of the conveying device 118 extend along the length direction of the furnace chamber 110 to convey the processing element 103 through the various heating subregions 115 in turn. Each heating subregion 115 includes an upper divider 341 and a lower divider 342. By disposing the upper divider 341 and the lower divider 342, the fans 213 of the upper furnace chamber 102 and the lower furnace chamber 104 are capable of driving the furnace chamber gas to circulate and flow in the heating subregion 115 to form a gas internal circulation channel 335. In particular, the gas internal circulation channel 335 includes an upper suction channel 333 and an upper exhaust channel 331 formed inside the upper furnace chamber 102, and a lower suction channel 334 and a lower exhaust channel 332 formed inside the lower furnace chamber 104. Here, Fig. 3A illustrates the upper exhaust channel 331 and the lower exhaust channel 332, and Fig. 3B illustrates the upper suction channel 333 and the lower suction channel 334. Tn the present example, the upper divider 341 and the lower divider 342 have substantially the same shape. Further in combination with Fig. 3C, the upper divider 341 is a box body shape with openings 345 at both ends in the width direction W and is spaced at a certain distance from the furnace chamber 110 in both the length direction L and the width direction W of the furnace chamber for the furnace chamber gas to flow therethrough.

[0040] As shown in Fig. 3 A, in each heating subregion 115, the furnace chamber gas discharged from the exhaust of the fan 213 of the upper furnace chamber 102 flows downwardly from both sides in the length direction L of the furnace chamber 110, diffuses through a porous plate 343, and then evenly flows towards the processing element 103 in the conveying channel 112 to form the upper exhaust channel 331. Further, the furnace chamber gas discharged from the exhaust of the fan 213 of the lower furnace chamber 104 flows upwardly from both sides in the length direction L of the furnace chamber 110, similarly diffuses through a porous plate 344, and then evenly flows towards the processing element 103 in the conveying channel 112 to form the lower exhaust channel 332. [0041] As shown in Fig. 3B, in each heating subregion 115, after the furnace chamber gas in the conveying channel 112 flows upwardly from both sides in the width direction W of the furnace chamber 110, the furnace chamber gas enters the upper divider 341 through the opening 345 of the upper divider 341 towards the middle portion, and flows to and is received by a suction port of the fan 213 of the upper furnace chamber 102 to form the upper suction channel 333. Likewise, after the gas in the conveying channel 112 flows downwardly from both sides in the width direction W of the furnace chamber 110, the gas enters the lower divider 342 through the opening 346 of the lower divider 342 towards the middle portion, and flows to and is received by a suction port of the fan 213 of the lower furnace chamber 104 to form the lower suction channel 334. As such, with the drive of the fan 213, the furnace chamber gas in each heating subregion 115 is able to form a gas internal circulation channel 335 so that the furnace chamber gas can circulate in each heating subregion 115.

[0042] The heat exchange channel 123 of the heat exchange device 120 is disposed in the upper suction channel 333 such that the furnace chamber gas in the gas internal circulation channel 335 needs to flow through the heat exchange channel 123 during circulation for heat exchange with the air in the heat exchange channel 123. In the present example, the heating elements 211 are inserted into the boxes of the upper divider 341 and the lower divider 342, respectively, from the opening 345 of the upper divider 341 and the opening 346 of the lower divider 342. The heat exchange channel 123 of the heat exchange device 120 is disposed above the heating element 211 in the upper divider 341. The heat exchange channel 123 of the heat exchange device 120 is not provided within the lower divider 342.

[0043] hi particular, the heat exchange device 120 includes a heat exchange tube 326 having a tube wall 327, and the heat exchange channel 123 is enclosed by the tube wall 327. The outer surface of the tube wall 327 can be in contact with the furnace chamber gas and the inner surface can be in contact with the air in the heat exchange channel 123 such that the air within the heat exchange channel 123 is capable of heat exchange with the furnace chamber gas outside the heat exchange channel 123 through the tube wall 327. In the present example, the tube wall is square in shape to maximize the contact area of the heat exchange tube 326 with the furnace chamber gas. As one example, the heat exchange tube 326 also includes a plurality of fins 328 connected within the tube wall 327 of the heat exchange tube 326 to increase the area of contact of the heat exchange tube 326 with the air in the heat exchange channel 123.

[0044] In some processing furnaces, components such as rollers (not shown) associated with the conveying device 118 are often required in the lower furnace chamber 104, so the present example sets the heat exchange tube 326 in the gas internal circulation channel 335 corresponding to the upper furnace chamber 102. Depending on the specific structure of the processing furnace, in other examples, the heat exchange tube 326 may also be provided in the gas internal circulation channel 335 corresponding to the lower furnace chamber 104. [0045] It will be understood by those skilled in the art that an example of one structure of the upper and lower dividers are given in the present example. In other examples, the upper and lower dividers may have other shapes and structures and, accordingly, the gas internal circulation channels have different flow paths. Moreover, the heat exchange device of the present application is not limited to one structure in the example, and those skilled in the art may also design the heat exchange channel to be of different shapes and structures depending on the different flow paths of the furnace chamber gas. It is only necessary to ensure that when the furnace chamber gas flows in the internal circulation channel, the gas flows through a corresponding heat exchange tube and exchanges heat with the air in the heat exchange channel.

[0046] Figs. 4A to 4E illustrate specific structures of the heat exchange device 120. Here, Fig. 4A shows a perspective view of the heat exchange device 120, Fig. 4B shows a stereo exploded view of the heat exchange device 120 from another angle, Fig. 4C shows a top view of the heat exchange tube 326, and Fig. 4D and Fig. 4E show cross-sectional views of the heat exchange tube 326 along the C-C line and the D-D line, respectively. As shown in Figs. 4A to 4E, the heat exchange tube 326 is in a "U" shape, including a first side tube 436 and a second side tube 437 disposed side by side, with the first side tube 436 and the second side tube 437 being square tubes having approximately the same length. The proximal end of the first side tube 436 forms the heat exchange channel inlet 121, the proximal end of the second side tube 437 forms the heat exchange channel outlet 122, and the distal end of the first side tube 436 and the distal end of the second side tube 427 are connected and in fluid communication through a connecting tube 438. The interiors of the first side tube 436, the connecting tube 438, and the second side tube 427 are in communication with each other to collectively form the heat exchange channel 123. In the present example, the heat exchange channel inlet 121 is disposed at an end of the first side tube 436 perpendicular to the extending direction of the heat exchange channel 123 for fluid communication with an air outlet of the centrifugal fan 214, so as to receive air discharged from the air outlet of the centrifugal fan 214. The heat exchange channel outlet 122 is disposed on the top of the second side tube 437 perpendicular to the heat exchange channel inlet 121 to facilitate connection with the heat exchange channel outlet 122 of the other heat exchange devices 120 through the air discharge duct 125. Fig. 4D shows a cross-sectional view of the second side tube 437 and the heat exchange channel outlet 122, and Fig. 4E shows a cross-sectional view of the first side tube 436 and the heat exchange channel inlet 121.

[0047] The fin 328 is disposed inside the first side tube 436 and the second side tube 437 and extends in a length direction along the first side tube 436 and the second side tube 437. One edge of each fin 328 is connected to the tube wall 327 of the first side tube 436 and the second side tube 437, and the other side is spaced a distance from the tube wall 327 of the corresponding first side tube 436 and second side tube 437 for air flow. The fins 328 are capable of increasing the area of contact of the tube wall 327 of the heat exchange tube 326 with the air inside the tube, and the fins 328 may also be capable of conducting heat of the tube wall 327 through connection with the tube wall 327.

[0048] hi the present example, the centrifugal fan 214 is particularly suitable to drive outside air into the heat exchange channel 123. The centrifugal fan 214 is capable of increasing the pressure of the outside air to allow air entering the heat exchange channel 123 to exchange heat and discharge smoothly in the heat exchange channel 123. By setting the parameters of the centrifugal fan 214, the flow rate and flow capacity of the external air entering the heat exchange channel 123 can be adjusted, thereby facilitating adjustment of the temperature of the furnace chamber gas to a preset temperature by heat exchange. When there is no need to lower the temperature of the furnace chamber gas, it is only necessary to turn off the centrifugal fan 214.

[0049] The outside air is driven by the centrifugal fan 214 into the heat exchange channel 123 from the heat exchange channel inlet 121, first flowing from left to right to the connecting tube 438 along the length direction of the first side tube 436 as shown in Fig. 4E, and then flowing into the second side tube 437 through the connecting tube 438. Then the air flows from right to left along the length direction of the second side tube 437 as shown in Fig. 4D, and finally exits upwardly from the heat exchange channel outlet 122.

[0050] In a processing furnace, for different processing elements, there may be different requirements for the temperature of the furnace chamber gas. Particularly the temperature of the furnace chamber gas in the heating zone may affect the processing quality of the processing element, and therefore it is necessary to adjust the temperature of the furnace chamber gas in the heating zone to a predetermined temperature prior to processing. In the case of continuously processing the processing elements in the processing furnace, when the temperature of the furnace chamber gas is lower than a predetermined temperature required for subsequent processing elements, the temperature of the furnace chamber gas may be heated to a predetermined temperature directly through the heating element. When the temperature of the furnace chamber gas is higher than the predetermined temperature required for subsequent processing elements, it is necessary to lower the temperature of the furnace chamber gas to the predetermined temperature. In general, lowering the temperature of the furnace chamber gas is achieved by replenishing the outside air to the furnace chamber due to the generally higher temperature of the furnace chamber gas and the relatively lower temperature of the outside air. Although the temperature of the furnace chamber gas can be lowered to a predetermined temperature by mixing gases, it may affect the composition of the furnace chamber gas. For example, in some processing furnaces where the working gas is substantially inert (e.g., nitrogen), replenishing the outside air to the furnace chamber will destroy the oxygen and nitrogen content in the furnace chamber gas. Therefore, after the temperature of the furnace chamber gas is lowered to the predetermined temperature required for the subsequent processing element, it is still necessary to replenish the furnace chamber with inert gas such as nitrogen, which is costly and time consuming. [0051] The present application provides a processing furnace that can conveniently adjust the temperature of the furnace chamber gas and does not affect the composition of the furnace chamber gas. The processing furnace of the present application includes a heat exchange device for heat exchange of the furnace chamber gas with outside air to lower the temperature of the furnace chamber gas in the heating zone by heat exchange. When the temperature of the furnace chamber gas is higher than the predetermined temperature required for the subsequent processing element, it is possible to exchange heat between the high-temperature gas in the furnace chamber with the outside low-temperature air by the heat exchange device, thereby achieving the purpose of lowering the temperature of the furnace chamber gas to the predetermined temperature. When there is no need to lower the temperature of the furnace chamber gas, it is only necessary to turn off the centrifugal fan of the heat exchange device to stop the flow of the outside air in the heat exchange channel, which avoids the temperature of the furnace chamber gas from lowering, and to selectively heat the furnace chamber gas through the heating element according to the predetermined temperature required for the subsequent processing element. As such, the processing furnace of the present application is capable of conveniently and quickly adjusting the temperature of the furnace chamber gas. It is particularly suitable where the temperature of the furnace chamber gas needs to be quickly adjusted from high to low temperatures.

[0052] Moreover, the heat exchange device in the processing furnace of the present application does not affect the composition of the furnace chamber gas and there is no need to adjust the gas content after lowering the gas temperature in the furnace chamber, which is particularly suitable for a processing furnace using a substantially inert gas as the working gas.

[0053] Although the present disclosure has been described in connection with examples outlined above, various alternatives, modifications, variations, improvements, and/or substantial equivalents, whether known or foreseeable now or in the near future, may be apparent to those having at least ordinary skill in the art. In addition, the technical effects and/or technical problems described in the present specification are exemplary and not limiting; therefore, the disclosure in the present specification may be used to solve other technical problems and have other technical effects and/or may solve other technical problems. Therefore, examples of the present disclosure as set forth above are intended to be illustrative and not limiting. Various changes may be made without departing from the spirit or scope of the present disclosure. Therefore, the present disclosure is intended to include all known or earlier developed alternatives, modifications, variations, improvements and/or substantial equivalents.