Oven for metal processing

Abstract

The present invention relates to the technical field of ovens, and specifically to an oven for metal processing, comprising an oven chamber with upper and lower openings, wherein side wall air cavities are symmetrically arranged at both sides of the interior of the oven chamber, and a translation sliding cover plate capable of translational sliding opening and closing is arranged at the upper opening of the oven chamber, a heating slot is penetrated through the side wall of the side wall air cavity, a quartz electric heating tube is arranged in the heating slot, an axial flow air duct is embedded and installed on the side wall of the side wall air cavity, and the axial flow air duct is used to transport gas into the side wall air cavity; the present invention can make the airflow in the oven circulate inside and outside during the drying process, enhance the dissipation of water vapor, and improve the drying efficiency; and after the drying is completed, when entering the preheating process, the airflow in the oven circulates internally to reduce heat loss.

Description

Technical Field

[0001] The invention relates to the technical field of ovens, in particular to an oven used for metal processing. Background Art

[0002] Before painting, metal workpieces need to be pickled or washed with water to remove oxides and impurities on the surface of the metal workpieces. The pickled or washed metal workpieces need to be sent to an oven for rapid drying and preheating. The preheated metal workpieces can then be painted to improve the adhesion and durability of the paint. The oven in traditional technology can achieve uniform heating of the workpiece by driving the air flow to circulate internally, but it is not conducive to the drying process in the front stage, and the water vapor discharge efficiency is low during the front drying stage. The oven heated by external circulation has a high water vapor discharge efficiency in the front stage, but when entering the preheating stage, the heat loss is large, the heating speed is slow and it is not conducive to energy saving. Summary of the invention

[0003] The object of the present invention is to provide an oven for metal processing to solve the problems raised in the above background technology.

[0004] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: an oven for metal processing, comprising an oven chamber with upper and lower openings, side wall air cavities are symmetrically arranged at both sides of the interior of the oven chamber, a sliding cover plate that can slide and open and close is arranged at the upper opening of the oven chamber, a heating slot is arranged through the side wall of the side wall air cavity, a quartz electric heating tube is arranged in the heating slot, an axial flow air duct is embedded and installed on the side wall of the side wall air cavity, the axial flow air duct is used to transport gas into the side wall air cavity, a closed upper eave and a closed lower eave are fixedly arranged on the side wall surface of the side wall air cavity, the closed upper eave is located above the closed lower eave, and the axial flow air duct is located between the closed upper eave and the closed lower eave, an intermediate support plate is fixedly arranged on the inner wall surface of the oven chamber near the lower opening, a windshield structure with a rotating function is arranged on the outside of the intermediate support plate, and a workpiece fence for storing metal workpieces is arranged in the oven chamber.

[0005] The wind shield structure includes a switching sealing shaft and a switching wind shield. The switching sealing shaft is in air-tight contact with the intermediate support plate. A switching wind shield is fixedly provided on the surface of the switching sealing shaft, and the switching wind shield can be driven to swing by the rotation of the switching sealing shaft. When the switching wind shield is in contact with the closed upper eaves, the axial flow wind duct draws in outside air through the lower opening of the oven compartment. When the switching wind shield is in contact with the closed lower eaves, the axial flow wind duct directly draws in air in the oven compartment. An air intake filter membrane for filtering gas is provided at the lower opening of the oven compartment.

[0006] A limiting outer frame is fixedly provided on the inner wall surface of the oven chamber, and a flow balancing plate is provided in the limiting outer frame. The flow balancing plate is a cavity plate-like structure, and the flow balancing plate is limited by the limiting outer frame so that the flow balancing plate can only be raised and lowered inside the limiting outer frame.

[0007] A lifting drive cylinder is arranged between the flow-evening plate and the middle support plate, and the flow-evening plate is driven by the lifting drive cylinder to lift and lower compared with the limiting outer frame. A blower is fixedly arranged on the surface of the limiting outer frame, and a movable connecting air duct is connected to the gas output port of the blower. The movable connecting air duct is fixedly connected to the flow-evening plate, so that the blower can input gas into the flow-evening plate.

[0008] A fixed top pipe is fixedly arranged on the upper surface of the flow-evening plate. The fixed top pipe is a tubular structure, and the lower end of the fixed top pipe is connected to the inner cavity of the flow-evening plate. The two fixed top pipes are uniformly distributed in a linear array along the length direction of the limiting outer frame as a group.

[0009] An interconnecting transverse plate is fixedly connected between the fixed top pipes, the length direction of the interconnecting transverse plate is perpendicular to the length direction of the limiting outer frame, and a pressure-sensitive split plate is arranged above the interconnecting transverse plate.

[0010] A cylindrical inner cavity is opened in the interconnected horizontal plate, and a regulating piston disk is airtightly and slidingly arranged in the cylindrical inner cavity. A regulating optical axis is fixedly arranged on the upper surface of the regulating piston disk. The upper end of the regulating optical axis is sealed and inserted through the top of the cylindrical inner cavity and extends to the outside of the interconnected horizontal plate. The upper end of the regulating optical axis is fixedly installed with the pressure-sensitive split plate.

[0011] The interconnected horizontal plate is provided with a spring receiving groove which is interconnected with the cylindrical inner cavity. An arched spring is arranged below the regulating piston disk. Both sides of the arched spring extend into the spring receiving groove. The arched spring provides an upward supporting elastic force for the regulating piston disk. A breathing hole is provided through the bottom of the cylindrical inner cavity.

[0012] A beam ring cavity is arranged on the side wall of the fixed top tube, and an elastic beam sleeve is arranged in the beam ring cavity. The gas flowing through the fixed top tube will pass through the inner side of the elastic beam sleeve, and the outer side of the elastic beam sleeve cooperates with the beam ring cavity to form a closed ring cavity. A gas connecting cavity is opened in the interconnecting cross plate, and one end of the gas connecting cavity is connected with the above-mentioned closed ring cavity, and the other end is connected with the top of the cylindrical inner cavity.

[0013] A protective vertical fence is fixedly arranged in the heating slot to protect the quartz electric heating tube. Both ends of the workpiece fence are respectively fixedly arranged with fence vertical rods, and the upper ends of the fence vertical rods are fixedly installed with beam suspension rods.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] The oven for metal processing of the present invention can, during the drying process, switch the wind shield and close the upper eaves to make the air flow in the oven circulate inside and outside, enhance the dissipation of water vapor, and improve the drying efficiency; and after the drying is completed, when entering the preheating process, the air flow in the oven circulates internally by switching the wind shield and closing the lower eaves to reduce heat loss, improve preheating efficiency, and save more energy.

[0016] By cooperating with the fixed jacking pipe, interconnected transverse plates, blower and other structures, the fixed jacking pipe and the interconnected transverse plates can be controlled to slowly cycle and lift during the process of drying or preheating the metal workpieces. The fixed jacking pipe and the interconnected transverse plates will pass through the workpiece frame to lift and push the metal workpieces piled up in the workpiece frame, thereby increasing the gap between the workpieces and improving the drying or preheating efficiency. When the fixed jacking pipe is inserted into the interior of the piled metal workpieces, the blower inhales the hot air flow and sprays it directly from the fixed jacking pipe to the interior of the piled metal workpieces, so that the interior of the piled workpieces is fully dried.

[0017] Through the coordination of the pressure-sensitive split plate, cylindrical inner cavity, elastic beam sleeve and other structures, the weight of the workpiece being lifted and pushed can be detected, and the output flow rate of the fixed jacking pipe can be automatically adjusted according to the weight; when the workpieces are not evenly stacked in the workpiece frame, after the fixed jacking pipe is inserted into the workpiece frame, the pressure on the pressure-sensitive split plate is different, and the pressure on the pressure-sensitive split plate is greater where the workpieces are piled up more. At this time, the piston disc is controlled to move downward more, and a larger negative pressure is automatically generated, which attracts the elastic beam sleeve to expand more, reduces the beam effect of the elastic beam sleeve, and increases the jet flow of the fixed jacking pipe; thereby automatically increasing the jet flow in places where the workpieces are piled up more, and realizing automatic distribution. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0019] Figure 2 It is a three-dimensional half-section schematic diagram of the present invention.

[0020] Figure 3 for Figure 2 A magnified schematic diagram of area A in the middle.

[0021] Figure 4 It is a three-dimensional half-section front view of the present invention.

[0022] Figure 5 It is a half-section schematic diagram of the fixing jacking pipe of the present invention.

[0023] Figure 6 for Figure 5 Enlarged schematic diagram of area B in the middle.

[0024] Figure 7 for Figure 6 Enlarged schematic diagram of area C in the middle.

[0025] In the figure: 1. oven compartment; 2. side wall air cavity; 3. translation sliding cover; 4. heating notch; 5. quartz electric heating tube; 6. axial flow air duct; 7. closed upper eaves; 8. closed lower eaves; 9. middle support plate; 10. workpiece fence; 901. switch sealing shaft; 902. switch wind shield; 903. air inlet filter membrane; 101. limit outer frame; 102. uniform air flow plate; 103. lifting drive cylinder; 104. blower; 105. movable Connecting air duct; 106, fixing top pipe; 107, interconnecting horizontal plates; 108, pressure-sensitive split plate; 109, cylindrical inner cavity; 110, regulating piston disk; 111, regulating optical axis; 112, shrapnel receiving groove; 113, arched shrapnel; 114, breathing hole; 115, beam ring cavity; 116, elastic beam sleeve; 117, gas connecting cavity; 401, protective vertical railing; 1001, fence vertical rod; 1002, beam hanger. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] The present invention provides a technical solution: an oven for metal processing, such as Figure 2 As shown in the figure, it comprises an oven cabinet 1 with upper and lower openings, side wall air chambers 2 are symmetrically arranged at both sides of the interior of the oven cabinet 1, a translation sliding cover plate 3 which can be translated and slid to open and close is arranged at the upper opening of the oven cabinet 1, a rack is fixedly installed on the translation sliding cover plate 3, and the rack is driven by the gear to enable the translation sliding cover plate 3 to be translated and slid to open and close, a heating slot 4 is opened through the side wall of the side wall air chamber 2, a quartz electric heating tube 5 is arranged in the heating slot 4, an axial flow air duct 6 is embedded in the side wall of the side wall air chamber 2, and the axial flow air duct 6 consists of The oven chamber 1 is composed of a circular tube and an internal fan, the axial flow air duct 6 is used to transport gas to the side wall air cavity 2, the side wall surface of the side wall air cavity 2 is fixedly provided with a closed upper eave 7 and a closed lower eave 8, the closed upper eave 7 is located above the closed lower eave 8, and the axial flow air duct 6 is located between the closed upper eave 7 and the closed lower eave 8, the inner wall surface of the oven chamber 1 is fixedly provided with an intermediate support plate 9 near the lower opening, the outside of the intermediate support plate 9 is provided with a windshield structure with a rotating function, and the oven chamber 1 is provided with a workpiece fence 10 for storing metal workpieces.

[0028] like Figure 2As shown in the figure, the wind shield structure includes a switching sealing shaft 901 and a switching wind shield 902. The switching sealing shaft 901 is in airtight contact with the middle support plate 9. The switching sealing shaft 901 is driven to rotate by a motor. A switching wind shield 902 is fixedly provided on the surface of the switching sealing shaft 901. The rotation of the switching sealing shaft 901 can drive the switching wind shield 902 to swing; when the switching wind shield 902 is in contact with the closed upper eaves 7, the axial flow air duct 6 inhales outside air through the lower opening of the oven chamber 1; when the switching wind shield 902 is in contact with the closed lower eaves 8, the axial flow air duct 6 directly inhales the air in the oven chamber 1; an air intake filter membrane 903 for filtering gas is provided at the lower opening of the oven chamber 1.

[0029] like Figure 3 As shown in the figure, a limiting outer frame 101 is fixedly provided on the inner wall surface of the oven chamber 1, and an even flow plate 102 is provided in the limiting outer frame 101. The even flow plate 102 is a cavity plate structure. The even flow plate 102 is limited by the limiting outer frame 101 so that the even flow plate 102 can only be raised and lowered inside the limiting outer frame 101.

[0030] A lifting drive cylinder 103 is arranged between the flow-evening plate 102 and the middle support plate 9. The lifting drive cylinder 103 drives the flow-evening plate 102 to move up and down compared with the limiting outer frame 101. A blower 104 is fixedly arranged on the surface of the limiting outer frame 101. A movable connecting air duct 105 is connected to the gas output port of the blower 104. The movable connecting air duct 105 is fixedly connected to the flow-evening plate 102, so that the blower 104 can input gas into the flow-evening plate 102.

[0031] A fixed top pipe 106 is fixedly provided on the upper surface of the flow-evening plate 102. The fixed top pipe 106 is a tubular structure, and the lower end of the fixed top pipe 106 is connected to the inner cavity of the flow-evening plate 102. Two fixed top pipes 106 are grouped together and evenly distributed in a linear array along the length direction of the limiting outer frame 101.

[0032] An interconnecting transverse plate 107 is fixedly connected between the fixed top pipes 106 . The length direction of the interconnecting transverse plate 107 is perpendicular to the length direction of the limiting outer frame 101 . A pressure-sensitive split plate 108 is arranged above the interconnecting transverse plate 107 .

[0033] A cylindrical inner cavity 109 is opened in the interconnecting horizontal plate 107, and a regulating piston disk 110 is airtightly and slidingly arranged in the cylindrical inner cavity 109. A regulating optical axis 111 is fixedly arranged on the upper surface of the regulating piston disk 110. The upper end of the regulating optical axis 111 is sealed and inserted through the top of the cylindrical inner cavity 109 and extends to the outside of the interconnecting horizontal plate 107. The upper end of the regulating optical axis 111 is fixedly installed with the pressure-sensitive split plate 108.

[0034] A spring receiving groove 112 which is interconnected with the cylindrical inner cavity 109 is provided in the interconnecting horizontal plate 107, and an arched spring 113 is arranged below the regulating piston disk 110. Both sides of the arched spring 113 extend into the spring receiving groove 112. The arched spring 113 provides an upward supporting elastic force for the regulating piston disk 110. A breathing hole 114 is provided through the bottom of the cylindrical inner cavity 109, and the breathing hole 114 is used to balance the air pressure below the regulating piston disk 110.

[0035] A beam ring cavity 115 is disposed on the side wall of the fixed top tube 106, and an elastic beam sleeve 116 is disposed in the beam ring cavity 115. The gas flowing through the fixed top tube 106 passes through the inner side of the elastic beam sleeve 116, and the outer side of the elastic beam sleeve 116 cooperates with the beam ring cavity 115 to form a closed ring cavity. A gas communication cavity 117 is provided in the interconnection cross plate 107, and one end of the gas communication cavity 117 is connected to the above-mentioned closed ring cavity, and the other end is connected to the top of the cylindrical inner cavity 109; Figure 7 As shown in , the cross section of the elastic beam sleeve 116 is in the shape of an inverted bracket under normal pressure. The airflow will be beamed when passing through the elastic beam sleeve 116. When the elastic beam sleeve 116 expands outwards under the suction of negative pressure, the beam effect gradually weakens.

[0036] A protective vertical fence 401 is fixedly provided in the heating slot 4 to protect the quartz electric heating tube 5. Vertical fence bars 1001 are fixedly provided at both ends of the workpiece fence 10, and a crossbeam suspension rod 1002 is fixedly installed at the upper end of the vertical fence bar 1001.

[0037] In the oven for metal processing of the present invention, metal workpieces are stacked in the workpiece fence 10 during operation, and the workpiece fence 10 is suspended by the crossbeam suspension rod 1002 and placed inside the oven chamber 1.

[0038] When drying the workpiece in the initial stage, the translation sliding cover plate 3 is first controlled not to be completely closed, leaving a certain gap for exhausting gas; the switching sealing shaft 901 is driven by the motor to rotate, so that the switching sealing shaft 901 drives the switching windshield plate 902 to rotate, such as Figure 2 As shown in , the switchable wind shield 902 is in contact with the lower surface of the closed upper eave 7. At this time, the axial flow wind tube 6 is running, and the gas is drawn into the inside of the side wall wind cavity 2. Due to the obstruction of the switchable wind shield 902, the axial flow wind tube 6 can only draw the outside air through the air inlet filter 903 and input it into the side wall wind cavity 2; the gas in the side wall wind cavity 2 is heated by the quartz electric heating tube 5 and then ejected from the heating slot 4 to dry the workpiece in the workpiece fence 10. The gas containing a large amount of water vapor is finally discharged to the outside through the gap left by the translation sliding cover plate 3, which can effectively enhance the efficiency of water vapor dissipation.

[0039] To determine whether the workpiece is dried, a humidity sensor can be set inside the oven cabinet 1 for detection. After the workpiece is dried, during preheating, the translation sliding cover 3 is controlled to be completely closed, and the switch windshield 902 is rotated downward, and the switch windshield 902 is in contact with the closed lower eaves 8 to close the lower opening of the oven cabinet 1. At this time, the axial flow air duct 6 operates to extract the high-temperature gas inside the oven cabinet 1 for internal circulation heating, thereby reducing heat loss and improving preheating efficiency.

[0040] In the above process, the lifting drive cylinder 103 slowly extends and retracts, and the blower 104 runs at the same time; the operation of the blower 104 will draw the gas inside the oven chamber 1 and input it into the uniform flow plate 102 through the movable connecting air duct 105, and finally spray it upward through the fixed top pipe 106; and the slow extension and retraction movement of the lifting drive cylinder 103 can drive the uniform flow plate 102, the fixed top pipe 106 and the interconnected cross plate 107 and other components to move synchronously and slowly up and down.

[0041] When the fixed jacking pipe 106 and the interconnected cross plate 107 move upward, they will be inserted into the workpiece fence 10 through the bottom gap of the workpiece fence 10, pushing the workpieces piled up in the workpiece fence 10 to move, so that the workpieces piled up in the middle position at the bottom of the workpiece fence 10 are lifted up, and the gap between the workpieces is increased to facilitate gas circulation and improve the drying or preheating effect. The lifting cross-section of the fixed jacking pipe 106 is increased by setting the interconnected cross plate 107 and the pressure-sensitive split plate 108; and the fixed jacking pipe 106 sprays gas directly to the inside of the piled metal workpieces, so that the inside of the piled workpieces is fully dried.

[0042] When the workpieces are not evenly stacked in the workpiece frame 10, after the fixed jacking pipe 106 is inserted into the workpiece frame 10, the pressure on the pressure-sensitive split plate 108 is different, that is, the pressure on the pressure-sensitive split plate 108 is greater where the workpieces are piled up more, such as Figure 7 As shown in , by regulating the conduction of the optical axis 111 and the regulating piston disk 110, the regulating piston disk 110 moves downward to force the arch spring piece 113 to deform elastically. Since the pressure-sensitive split plate 108 is subjected to a greater downward pressure, the regulating piston disk 110 moves downward more in the cylindrical inner cavity 109 at this time, and the negative pressure generated above the regulating piston disk 110 is greater. The negative pressure is transmitted to the outer side of the elastic beam sleeve 116 through the gas connecting cavity 117 and the closed ring cavity formed by the beam ring cavity 115, so that the elastic beam sleeve 116 expands under the suction of the negative pressure, as shown in FIG. Figure 7 As shown in , when the elastic beam sleeve 116 expands, the beam effect on the airflow flowing inside the fixed top pipe 106 is weakened, so that the jet flow of the fixed top pipe 106 increases, thereby automatically increasing the jet flow of the fixed top pipe 106 in places where more workpieces are accumulated, thereby achieving automatic distribution.

[0043] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An oven for metal processing, comprising an oven chamber (1) with upper and lower openings, characterized in that: Side wall air cavities (2) are symmetrically arranged at both sides of the interior of the oven chamber (1); a sliding cover plate (3) capable of sliding and opening in translation is arranged at the upper opening of the oven chamber (1); a heating slot (4) is provided through the side wall of the side wall air cavity (2); a quartz electric heating tube (5) is arranged in the heating slot (4); an axial flow air duct (6) is embedded in the side wall of the side wall air cavity (2); the axial flow air duct (6) is used to transport gas into the side wall air cavity (2); a closed upper eave (7) and a closed lower eave (8) are fixedly arranged on the side wall surface of the side wall air cavity (2); the closed upper eave (7) is located above the closed lower eave (8); The axial flow air duct (6) is located between the closed upper eaves (7) and the closed lower eaves (8); an intermediate support plate (9) is fixedly provided on the inner wall surface of the oven chamber (1) near the lower opening; a windshield structure with a rotating function is provided outside the intermediate support plate (9); a workpiece fence (10) for storing metal workpieces is provided in the oven chamber (1); a limiting outer frame (101) is fixedly provided on the inner wall surface of the oven chamber (1); a uniform flow plate (102) is provided in the limiting outer frame (101); the uniform flow plate (102) is a cavity plate-shaped structure; the uniform flow plate (102) is limited by the limiting outer frame (101). , so that the uniform flow plate (102) can only move up and down inside the limiting outer frame (101); a lifting drive cylinder (103) is provided between the uniform flow plate (102) and the intermediate support plate (9), and the lifting drive cylinder (103) drives the uniform flow plate (102) to move up and down relative to the limiting outer frame (101); a blower (104) is fixedly provided on the surface of the limiting outer frame (101), and a movable connecting air duct (105) is provided at the gas output port of the blower (104); the movable connecting air duct (105) is fixedly connected to the uniform flow plate (102), so that the blower (104) can move gas to the uniform flow plate (102). 2) inputting gas; a fixed top pipe (106) is fixedly arranged on the upper surface of the gas flow balancing plate (102); the fixed top pipe (106) is a tubular structure, and the lower end of the fixed top pipe (106) is connected to the inner cavity of the gas flow balancing plate (102); two fixed top pipes (106) are uniformly distributed in a linear array along the length direction of the limiting outer frame (101); an interconnecting transverse plate (107) is fixedly connected between the fixed top pipes (106); the length direction of the interconnecting transverse plate (107) is perpendicular to the length direction of the limiting outer frame (101), and a pressure-sensitive split plate (108) is arranged above the interconnecting transverse plate (107);A cylindrical inner cavity (109) is provided in the interconnecting transverse plate (107), a regulating piston disc (110) is airtightly and slidably arranged in the cylindrical inner cavity (109), a regulating optical axis (111) is fixedly arranged on the upper surface of the regulating piston disc (110), the upper end of the regulating optical axis (111) is sealed and inserted through the top of the cylindrical inner cavity (109), and extends to the outside of the interconnecting transverse plate (107), and the upper end of the regulating optical axis (111) is fixedly installed with the pressure-sensitive split plate (108); a spring element receiving groove (112) which is interconnected with the cylindrical inner cavity (109) is provided in the interconnecting transverse plate (107), an arched spring element (113) is arranged below the regulating piston disc (110), and both sides of the arched spring element (113) extend into the spring element receiving groove (112). 12), the arched spring piece (113) provides an upward supporting elastic force for the regulating piston disc (110), and a breathing hole (114) is provided through the bottom of the cylindrical inner cavity (109); a beam ring cavity (115) is provided on the side wall of the fixed top tube (106), and an elastic beam sleeve (116) is provided in the beam ring cavity (115); the gas flowing through the fixed top tube (106) passes through the inner side of the elastic beam sleeve (116), and the outer side of the elastic beam sleeve (116) cooperates with the beam ring cavity (115) to form a closed ring cavity; a gas communication cavity (117) is provided in the interconnected horizontal plate (107), and one end of the gas communication cavity (117) is connected to the above-mentioned closed ring cavity, and the other end is connected to the top of the cylindrical inner cavity (109). ; 2. The oven for metal processing according to claim 1, characterized in that: The windshield structure comprises a switching sealing shaft (901) and a switching windshield (902); the switching sealing shaft (901) is in airtight contact with the intermediate support plate (9); a switching windshield (902) is fixedly provided on the surface of the switching sealing shaft (901); the switching windshield (902) can be driven to swing by the rotation of the switching sealing shaft (901); when the switching windshield (902) is in contact with the closed upper eaves (7), the axial flow air duct (6) inhales outside air through the lower opening of the oven chamber (1); when the switching windshield (902) is in contact with the closed lower eaves (8), the axial flow air duct (6) directly inhales air in the oven chamber (1); and an air intake filter membrane (903) for filtering gas is provided at the lower opening of the oven chamber (1).

3. The oven for metal processing according to claim 1, characterized in that: A protective vertical fence (401) is fixedly provided in the heating slot (4), and the quartz electric heating tube (5) is protected by the protective vertical fence (401). Fence vertical bars (1001) are fixedly provided at both ends of the workpiece fence (10), and a crossbeam suspension rod (1002) is fixedly installed at the upper end of the fence vertical bar (1001).

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