A hot air circulation reversing mechanism in a furnace

Abstract

The utility model relates to the technical field of roller transmission furnace, the utility model discloses a kind of hot air circulation reversing mechanism in furnace, including furnace body, furnace wind channel, reversing mechanism, variable frequency motor, volute, fan chamber and left and right support frame;The furnace wind channel is installed in furnace body inner top, combustion system is installed in furnace body side portion and extends into furnace wind channel;The fan chamber is installed in the intermediate position of furnace body top, the volute is installed in fan chamber with impeller, and the belt pulley of variable frequency motor is connected with the belt pulley of volute through belt;The reversing mechanism driven by standard compound action type air cylinder is arranged in the mechanism, can be realized 90 ° rotation of air distribution plate, and then switch hot air circulation direction;When one end of furnace body is heated faster, reversing mechanism can change hot air flow direction in time, so that high-temperature hot air enters hearth from the other end of furnace body, and balance two-end heating state.

Description

Technical Field

[0001] This utility model relates to the field of roller conveyor furnace technology, specifically to a furnace hot air circulation reversing mechanism. Background Technology

[0002] Currently, large and medium-sized roller conveyor furnaces generally employ a unidirectional hot air circulation method during heat treatment. This circulation method generates heat through burners and blows hot air into the furnace in a single, fixed direction. Specifically, hot air is blown in from the inlet, exchanges heat in the furnace chamber, and then is drawn into the blower chamber through a return air baffle at the outlet, forming a reciprocating cycle to increase the furnace temperature. However, this hot air circulation method has significant technical drawbacks, limiting the quality of heat treatment and energy utilization efficiency. On the one hand, unidirectional hot air circulation leads to poor temperature uniformity within the furnace. Because hot air is transported unidirectionally from the inlet to the outlet, the inlet directly receives the high-temperature air, resulting in a rapid temperature rise. However, as the hot air travels through the furnace, heat is continuously lost, causing the outlet temperature to rise slowly. This ultimately leads to a significant temperature difference between the two ends of the furnace, affecting the consistency of workpiece heat treatment. On the other hand, energy consumption is high. In unidirectional circulation mode, hot air must pass through the entire furnace to complete circulation. The large heat loss during long-distance transmission significantly prolongs the time required for the outlet to reach the preset furnace temperature, thus increasing the overall energy consumption of the heating furnace, which does not meet the industrial development requirements for energy conservation and emission reduction. Utility Model Content

[0003] The purpose of this invention is to provide a furnace hot air circulation reversing mechanism to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, this utility model provides the following technical solution: a furnace hot air circulation reversing mechanism, comprising a furnace body, a furnace air duct, a reversing mechanism, a variable frequency motor, a volute, a fan chamber, and left and right support frames; The furnace air duct is installed at the top of the furnace body, and the combustion system is installed on the side of the furnace body and extends into the furnace air duct; the fan chamber is installed at the middle position of the top of the furnace body, and the volute and impeller are installed together in the fan chamber; the pulley of the variable frequency motor is connected to the pulley of the volute via a belt. The reversing mechanism is installed at the connection between the blower chamber and the furnace air duct. The reversing mechanism includes a reversing guide plate, an air distribution plate, a return air baffle, a rotating shaft, a bearing with a seat, a swing arm, a cylinder connector, and a standard double-acting cylinder. All components of the reversing mechanism are connected by the rotating shaft and fixed to the left and right support frames by the bearing with a seat. The standard double-acting cylinder can drive the rotating shaft through the swing arm to rotate the air distribution plate relative to the reversing guide plate, thereby changing the direction of hot air circulation and making the heating state at both ends of the furnace body relatively balanced.

[0005] Preferably, the standard double-acting cylinder of the reversing mechanism is connected to the swing arm through a cylinder connector, the swing arm is fixedly connected to the rotating shaft, and the air distribution plate is fixedly connected to the rotating shaft and rotates synchronously with the rotating shaft.

[0006] Preferably, the rotation angle of the air distribution plate is 90°, and the rotation realizes the switching between two hot air circulation states: In state I, hot air enters the furnace from end A through the furnace air duct, and then returns to the furnace air duct from end B, and is sucked into the volute by the variable frequency motor through the return air baffle; In state II, hot air enters the furnace from end B through the furnace air duct, and then returns to the furnace air duct from end A, and is sucked into the volute by the variable frequency motor through the return air baffle.

[0007] Preferably, the variable frequency motor provides power for the hot air circulation through centrifugal force, driving the heat generated by the combustion system to form a circulating airflow.

[0008] Preferably, the portion of the combustion system extending into the furnace duct corresponds to the airflow channel of the furnace duct, ensuring that the generated heat can fully enter the furnace duct and participate in the circulation.

[0009] Preferably, the left and right support frames are symmetrically arranged on the top of the furnace body and on both sides of the blower chamber, for stable support of the bearing seat and the reversing mechanism.

[0010] Preferably, the return air baffle is fixedly installed at the corresponding position where the furnace air duct connects to the blower chamber, and corresponds to the air inlet end of the volute, to guide the circulating hot air smoothly into the volute.

[0011] Preferably, the guide plate is fixedly installed at the end of the air duct inside the furnace and is adapted to the rotation trajectory of the air distribution plate to guide hot air into the furnace in a preset direction.

[0012] Compared with the prior art, the beneficial effects of this utility model are: 1. Significantly improves furnace temperature uniformity: This mechanism, through a reversing mechanism driven by a standard double-acting cylinder, can achieve a 90° rotation of the air distribution plate, thereby switching the hot air circulation direction. When one end of the furnace body heats up faster, the reversing mechanism can promptly change the hot air flow direction, allowing high-temperature hot air to enter the furnace chamber from the other end of the furnace body, balancing the heating state at both ends. This solves the problem of large temperature differences between the air inlet and outlet ends in existing unidirectional circulation systems, ensuring consistent temperature in all areas of the furnace chamber and improving the heat treatment quality of workpieces.

[0013] 2. Effectively reduce energy consumption: The flexible switching of hot air circulation direction shortens the time for the furnace body to reach the preset temperature. Compared with the large amount of heat loss caused by long-distance hot air transmission in existing technologies, this mechanism reduces heat waste by balancing heating at both ends. At the same time, the variable frequency motor can adjust the power output according to the circulation demand, further reducing energy consumption and meeting the energy-saving requirements of industrial production.

[0014] 3. Simple and reliable structure with strong adaptability: The reversing mechanism is composed of national standard parts such as reversing guide plates, air distribution plates, and seated bearings. The structure is simple, and the procurement and maintenance of parts are convenient, which reduces the cost of equipment manufacturing and subsequent operation and maintenance. At the same time, the mechanism can be directly installed at the connection between the blower room and the air duct in the furnace without the need for large-scale modification of the existing roller conveyor furnace structure. It is suitable for various large and medium-sized roller conveyor furnaces and has a wide range of application prospects.

[0015] 4. High circulation stability: The reversing mechanism connects all components into a whole through a rotating shaft and is stably supported by left and right support frames. The standard double-acting cylinder drives the swing arm to rotate the rotating shaft. The action is precise and controllable, ensuring that the air distribution plate and the reversing guide plate are tightly matched. The hot air circulates stably in the preset direction, avoiding the problem of reduced circulation efficiency caused by airflow turbulence. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a diagram showing the airflow direction of the reversing mechanism in state I. Figure 3 This is a diagram showing the airflow direction under state II of the reversing mechanism.

[0017] Explanation of reference numerals in the attached drawings: 1. Furnace body; 2. Furnace internal air duct; 3. Reversing mechanism; 4. Variable frequency motor; 5. Volute; 6. Fan chamber; 7. Left and right support frames; 8. Reversing guide plate; 9. Air distribution plate; 10. Return air baffle; 11. Rotating shaft; 12. Bearing with seat; 13. Swing arm; 14. Cylinder connector; 15. Standard double-acting cylinder. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0019] Please see Figures 1-3 This utility model provides a technical solution for a furnace hot air circulation reversing mechanism: The core components of this furnace hot air circulation reversing mechanism include furnace body 1, furnace air duct 2, reversing mechanism 3, variable frequency motor 4, volute 5, fan chamber 6, and left and right support frames 7. The furnace air duct 2 is fixedly installed on the inner top of the furnace body 1, forming a dedicated channel for hot air transmission; the combustion system is installed on the side of the furnace body 1, and its heat output end extends directly into the furnace air duct 2, with the extended part precisely corresponding to the airflow channel of the furnace air duct 2, ensuring that the high-temperature heat generated by the combustion system can completely enter the furnace air duct 2 to participate in subsequent circulation, avoiding heat leakage and waste.

[0020] The blower chamber 6 is bolted to the middle of the top of the furnace body 1, serving as the mounting carrier for the power components. The volute 5, along with its internal impeller, is assembled inside the blower chamber 6. The variable frequency motor 4 is mounted on an adapter bracket on the outside of the blower chamber 6. The output pulley of the variable frequency motor 4 is connected to the input shaft pulley of the volute 5 via a transmission belt, forming a power transmission link to ensure that the variable frequency motor 4 can drive the impeller inside the volute to rotate stably.

[0021] The left and right support frames 7 are symmetrically welded to the top of the furnace body 1 and are located on both sides of the blower chamber 6. Their height is flush with the top of the blower chamber 6, which is used to provide stable support for the reversing mechanism 3. The reversing mechanism 3 is installed as a whole at the connection between the blower chamber 6 and the furnace air duct 2. This position is a key diversion node before the hot air enters the furnace, which can maximize the reversing efficiency.

[0022] The reversing mechanism 3 consists of a reversing guide plate 8, an air distribution plate 9, a return air baffle 10, a rotating shaft 11, a seated bearing 12, a swing arm 13, a cylinder connector 14, and a standard double-acting cylinder 15. All components are linked together via the rotating shaft 11. The reversing guide plate 8 is fixedly installed at the end of the furnace air duct 2, and its guide surface is adapted to the rotation trajectory of the air distribution plate 9. The air distribution plate 9 is fixedly connected to the rotating shaft 11 via a flat key and can rotate synchronously with the rotating shaft 11. The return air baffle 10 is fixed in the furnace air duct 2 near the blower chamber 6. The position is corresponding to the air inlet end of the volute 5; both ends of the rotating shaft 11 are mounted on the left and right support frames 7 through seated bearings 12. The seated bearings 12 are fixed to the left and right support frames 7 with set bolts to ensure that there is no radial offset during the rotation of the rotating shaft 11; one end of the swing arm 13 is welded and fixed to the rotating shaft 11, and the other end is movably connected to the piston rod of the standard double-acting cylinder 15 through the cylinder connector 14. The cylinder body of the standard double-acting cylinder 15 is fixed to the top of the furnace body 1 through the bracket to form a stable drive structure.

[0023] Hot air circulation and reversing process: The circulation power is provided by the variable frequency motor 4, and the circulation direction is switched by the reversing mechanism 3. Specifically, there are two circulation modes: State I and State II. The two modes can be switched automatically or manually according to the temperature distribution inside the furnace to ensure balanced heating at both ends of the furnace. The detailed working process is as follows: State I, A-end air intake recirculation mode: When the equipment is started, the combustion system begins to work and generates high-temperature heat, which directly enters the furnace air duct 2; at the same time, the variable frequency motor 4 is powered on and starts, driving the impeller in the volute 5 to rotate at high speed through belt drive. The centrifugal force generated by the impeller rotation creates negative pressure in the fan chamber 6, thereby forming a directional airflow in the furnace air duct 2.

[0024] At this time, the reversing mechanism 3 is in initial state I: the piston rod of the standard double-acting cylinder 15 is in a retracted state, and the rotating shaft 11 is kept stationary by the swing arm 13. The air distribution plate 9 and the reversing guide plate 8 form a specific angle guiding fit, guiding the hot air in the furnace air duct 2 into the furnace chamber from end A. After the hot air exchanges heat with the workpiece in the furnace chamber, its temperature decreases, and then it flows back from end B of the furnace body 1 to the return air section of the furnace air duct 2. Under the negative pressure generated by the volute 5, it enters the volute 5 through the guide of the return air baffle 10, and is then transported back to the furnace air duct 2 by the volute 5 to mix with the new heat generated by the combustion system, completing one hot air cycle in state I.

[0025] State II, B-end air intake recirculation mode: Since the furnace body 1 is usually large in span and long in length, there will be a certain amount of heat loss during the circulation of hot air in state I. As a result, the A end of the furnace body 1 heats up faster than the B end because it directly receives high temperature hot air, causing a temperature difference between the two ends. When the temperature detection device can be equipped with a conventional temperature sensor to detect that the temperature difference between the two ends reaches the preset threshold, the reversing mechanism 3 starts the reversing action.

[0026] After receiving the reversing signal, the piston rod of the standard double-acting cylinder 15 extends and pushes the swing arm 13 to rotate around the axis of the rotating shaft 11 through the cylinder joint 14. The swing arm 13 drives the rotating shaft 11 to rotate synchronously, and the air distribution plate 9, which is fixedly connected to the rotating shaft 11, rotates accordingly until the rotation angle reaches 90°. At this time, the reversing mechanism 3 switches to state II. The air distribution plate 9 and the reversing guide plate 8 form a new guiding relationship, guiding the hot air in the furnace air duct 2 to end B of the furnace body 1, so that the high-temperature hot air enters the furnace from end B. After the hot air is heat-exchanged in the furnace, it flows back to the furnace air duct 2 from end A, and then enters the volute 5 through the return air baffle 10 to complete the circulation.

[0027] Cyclic Switching and Balance Control: The piston rod extension and retraction of the standard double-acting cylinder 15 enables the air distribution plate 9 to switch back and forth between state I and state II. The hot air circulation directions are opposite in the two states, allowing for focused heating of ends A and B of the furnace body 1 respectively. In practical applications, the temperature control system can monitor the temperature at both ends of the furnace body in real time and automatically control the timing and stroke of the standard double-acting cylinder 15, ensuring that the air distribution plate 9 precisely completes a 90° rotation reversal. This ensures that the heating state at both ends of the furnace body 1 remains relatively balanced, ultimately achieving the goals of improving furnace temperature uniformity, shortening heating time, and reducing energy consumption.

[0028] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A furnace hot air circulation reversing mechanism, characterized in that, The furnace includes a furnace body (1), an internal air duct (2), a reversing mechanism (3), a variable frequency motor (4), a volute (5), a fan chamber (6), and left and right support frames (7). The internal air duct (2) is installed at the top inside the furnace body (1), and the combustion system is installed on the side of the furnace body (1) and extends into the internal air duct (2). The fan chamber (6) is installed at the middle position at the top of the furnace body (1), and the volute (5) along with its impeller is installed in the fan chamber (6). The pulley of the variable frequency motor (4) is connected to the pulley of the volute (5) via a belt. The reversing mechanism (3) is installed at the connection between the fan chamber (6) and the internal air duct (2). At the location, the reversing mechanism (3) includes a reversing guide plate (8), an air distribution plate (9), a return air baffle (10), a rotating shaft (11), a seated bearing (12), a swing arm (13), a cylinder connector (14), and a standard double-acting cylinder (15). All components of the reversing mechanism (3) are connected by the rotating shaft (11) and fixed on the left and right support frames (7) by the seated bearing (12). The standard double-acting cylinder (15) can drive the rotating shaft (11) through the swing arm (13 to drive the air distribution plate (9) to rotate relative to the reversing guide plate (8) to change the hot air circulation direction and make the heating state at both ends of the furnace body (1) relatively balanced.

2. The furnace hot air circulation reversing mechanism according to claim 1, characterized in that: The standard double-acting cylinder (15) of the reversing mechanism (3) is connected to the swing arm (13) through the cylinder connector (14). The swing arm (13) is fixedly connected to the rotating shaft (11). The air distribution plate (9) is fixedly connected to the rotating shaft (11) and rotates synchronously with the rotating shaft (11).

3. The furnace hot air circulation reversing mechanism according to claim 2, characterized in that: The rotation angle of the air distribution plate (9) is 90°. The rotation enables the switching of two hot air circulation states: In state I, the hot air enters the furnace from end A through the furnace air duct (2) and then returns to the furnace air duct (2) from end B. It is then sucked into the volute (5) by the variable frequency motor (4) through the return air baffle (10); In state II, the hot air enters the furnace from end B through the furnace air duct (2) and then returns to the furnace air duct (2) from end A. It is then sucked into the volute (5) by the variable frequency motor (4) through the return air baffle (10).

4. The furnace hot air circulation reversing mechanism according to claim 3, characterized in that: The variable frequency motor (4) provides power for hot air circulation through centrifugal force, driving the heat generated by the combustion system to form a circulating airflow.

5. The furnace hot air circulation reversing mechanism according to claim 4, characterized in that: The portion of the combustion system extending into the furnace air duct (2) corresponds to the airflow channel of the furnace air duct (2), ensuring that the generated heat can fully enter the furnace air duct (2) to participate in the circulation.

6. The furnace hot air circulation reversing mechanism according to claim 5, characterized in that: The left and right support frames (7) are symmetrically arranged on the top of the furnace body (1) and on both sides of the blower chamber (6) to stabilize and support the seated bearing (12) and the reversing mechanism (3).

7. The furnace hot air circulation reversing mechanism according to claim 6, characterized in that: The return air baffle (10) is fixedly installed at the corresponding position where the furnace air duct (2) connects to the blower chamber (6) and corresponds to the air inlet end of the volute (5) to guide the circulating hot air smoothly into the volute (5).

8. The furnace hot air circulation reversing mechanism according to claim 7, characterized in that: The guide plate (8) is fixedly installed at the end of the air duct (2) inside the furnace and is adapted to the rotation trajectory of the air distribution plate (9) to guide hot air into the furnace in a preset direction.

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