A tunnel furnace

Abstract

The present invention discloses a tunnel furnace, comprising a shell, a heat source structure, a baking structure, and a heat circulation structure, wherein the heat source structure, the baking structure, and the heat circulation structure are fixedly mounted on the shell, and the baking structure comprises a radiation plate assembly and a side plate, wherein the radiation plate assembly is composed of a radiation plate or a plurality of radiation plates; the radiation plate assembly and the side plate enclose a baking channel, and a heat exchange channel is arranged in the radiation plate assembly, wherein one end of the heat exchange channel is connected to the heat circulation structure, and the other end of the heat exchange channel, the heat source structure, and the heat circulation structure are connected in sequence, thereby forming a closed loop circulation channel; and an exhaust valve for connecting the circulation channel with the outside is arranged on the heat circulation structure. The tunnel furnace provided by the present invention has the advantages of energy saving and stable and controllable temperature.

Description

Technical Field

[0001] The invention relates to a heating device, in particular to a tunnel furnace. Background Art

[0002] Heat transfer is a complex phenomenon, which is generally divided into three basic modes: heat conduction, heat convection and heat radiation. The heat transfer process carried out in production and life is often a combination of these three basic modes in different proportions. The food baking process is accompanied by complex chemical and physical changes. Dehydration is a function of food baking. Conduction heating requires the product to contact the heat conduction plate, and the uncontacted parts are heated slowly; heat convection is to heat the product with a flowing medium, which has the best thermal effect, but the temperature fluctuates greatly; radiation heating has slow heat transfer, good constant temperature performance, and high energy utilization. Heat conduction, heat convection and heat radiation each have their own advantages and disadvantages. In the baking industry, choosing the right heating method for different products can achieve a more ideal effect. Summary of the invention

[0003] In order to overcome the insufficient energy utilization rate of the existing baking technology, the object of the present invention is to provide a tunnel furnace with high energy utilization rate and good temperature stability.

[0004] The purpose of the present invention is achieved by the following technical solutions:

[0005] A tunnel furnace comprises a shell, a heat source structure, a baking structure, and a heat circulation structure, wherein the heat source structure, the baking structure, and the heat circulation structure are fixedly mounted on the shell, the baking structure comprises a radiation plate assembly and a side plate, the radiation plate assembly is composed of one radiation plate or a plurality of radiation plates; the radiation plate assembly and the side plate enclose a baking channel, a heat exchange channel is arranged in the radiation plate assembly, one end of the heat exchange channel is connected to the heat circulation structure, and the other end of the heat exchange channel, the heat source structure, and the heat circulation structure are connected in sequence, thereby forming a closed loop circulation channel; an exhaust valve for connecting the circulation channel with the outside is arranged on the heat circulation structure. When the pressure or humidity in the circulating air is too high, the exhaust valve is opened to discharge part of the circulating air, reduce moisture and reduce pressure.

[0006] Furthermore, the baking structure further comprises a conveying device, which is installed in the baking channel. The conveying device mainly comprises an automatic conveyor belt and other mechanisms for conveying the baked items.

[0007] Furthermore, the baking channel comprises at least two parallel radiation plate assemblies. The two parallel radiation plate assemblies can make the baking object be heated more evenly.

[0008] Furthermore, the radiation plate includes an upper plate, a lower plate and a middle rib, the upper plate is fixedly connected to the lower plate, the middle rib is located between the upper plate and the lower plate and divides the gap between the upper plate and the lower plate to form the heat exchange channel. This structure is simple and can easily radiate heat into the baking channel.

[0009] Furthermore, an air inlet regulating device is provided on the heat exchange channel, the air inlet regulating device is communicated with the heat exchange channel, the air inlet regulating device comprises an air inlet bellows, a lower fixed plate, and an upper movable regulating plate, both the lower fixed plate and the upper movable regulating plate are provided with vents; the upper movable regulating plate is slidably connected with the lower fixed plate; the upper movable regulating plate and the lower fixed plate slide with each other, thereby controlling the ventilation volume of the vents. The air inlet regulating device is used only to control the air volume entering the heat exchange channel to achieve temperature control of the baking device.

[0010] Furthermore, the heat circulation structure includes a return air channel and a radiation circulation fan, the return air channel is connected to the radiation circulation fan, and the heat exchange channel is connected to the return air channel; the radiation circulation fan is provided with a damper for controlling the amount of return air. The damper is used to control the amount of cold air flowing into the heat source structure to achieve control of the overall temperature of the machine.

[0011] Furthermore, the heat source structure also includes a combustion tube; the combustion tube includes a sleeved inner tube and an outer tube; the inner tube is connected to the burner, and the hot gas generated by the burner is ejected from the inner tube to the gas premixing chamber; a gap is formed between the outer tube and the inner tube, the gap is connected to the radiation circulation fan, and the cold air in the radiation circulation fan is ejected to the gas premixing chamber through the gap, and the hot gas and the cold air have the same ejection direction. The sleeved inner and outer combustion tubes can prevent the cold air from interfering with the operation of the burner, and prevent the burner from extinguishing or working unstably.

[0012] Furthermore, the tunnel furnace also includes a control device, which includes an over-temperature sensing probe. The over-temperature sensing probe is installed in the gas premixing chamber and monitors the temperature in the gas premixing chamber to prevent the heat source structure from being damaged due to excessive temperature.

[0013] Furthermore, the control device also includes a temperature sensing probe, which monitors the temperature of the fan air inlet, so that the control device can adjust the temperature of the baking channel to bake different products.

[0014] Compared with the prior art, the baking structure in the tunnel furnace of the present invention includes two radiation plate assemblies. The two radiation plate assemblies plus two side plates form a baking channel. The two radiation plate assemblies can radiate and heat the baking channel. Compared with the heating method based mainly on heat convection, it saves more energy, has high energy utilization rate and better temperature stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A three-dimensional diagram of the tunnel furnace of the present invention;

[0016] Figure 2 for Figure 1 A schematic diagram of the internal structure of a tunnel furnace;

[0017] Figure 3 for Figure 2 Another schematic diagram of the internal structure of the tunnel furnace

[0018] Figure 4 for Figure 2 An exploded view of a radiation panel of a tunnel furnace;

[0019] Figure 5 for Figure 2 An exploded view of an air inlet regulating device of a tunnel furnace.

[0020] In the figure: 100, tunnel furnace; 10, shell; 12, observation window; 20, baking structure; 21, radiation plate assembly; 210, upper plate; 211, lower plate; 212, middle partition rib; 213, heat exchange channel; 214, air inlet adjustment device; 2140, air inlet bellows; 2141, upper movable adjustment plate; 2142, lower fixed plate; 2143, manual pull rod; 22, conveying device; 23, baking channel; 30, heat source structure; 31, burner; 32, combustion tube; 33, gas premixing chamber; 40, heat circulation structure; 41, return air channel; 42, radiation circulation fan; 420, exhaust valve; 51, over-temperature sensing probe; 52, humidity sensor; 53, temperature sensing probe. DETAILED DESCRIPTION

[0021] 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.

[0022] It should be noted that when a component is referred to as being "fixed to" another component, it may be directly on the other component or there may also be a component centered. When a component is considered to be "connected to" another component, it may be directly connected to the other component or there may also be a component centered. When a component is considered to be "set on" another component, it may be directly set on the other component or there may also be a component centered. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0024] See also Figures 1 to 5 A tunnel oven 100 of the present invention includes a shell 10, a baking structure 20, a heat source structure 30, a heat circulation structure 40 and a control device.

[0025] The shell 10 is provided with a plurality of observation windows 12. The plurality of observation windows 12 are arranged at intervals to facilitate observation of the product and temperature adjustment. The baking structure 20 includes two parallel radiation plate assemblies 21 and a conveying device 22. The two radiation plate assemblies 21 are fixedly connected and parallel to each other. The two radiation plate assemblies 21 and the side panels form a baking channel 23. The conveying device 22 is installed in the baking channel 23. Each radiation plate assembly 21 includes one or more radiation plates. Each radiation plate includes an upper plate 210, a lower plate 211 and a middle partition rib 212. The upper plate 210 is fixed to the lower plate 211. The middle partition rib 212 is located in the gap between the upper plate 210 and the lower plate 211, and the gap is divided into a plurality of heat exchange channels 213. Each radiation plate is provided with an air inlet regulating device 214, which includes an air inlet bellows 2140, a lower fixed plate 2142, an upper movable regulating plate 2141 and a manual pull rod 2143. The manual pull rod 2143 is fixedly installed on the upper movable regulating plate 2141, and the upper movable regulating plate 2141 is slidably installed on the air inlet bellows 2140. The position between the upper movable regulating plate 2141 and the lower fixed plate 2142 is adjusted by the manual pull rod 2143. By adjusting the relative position between the upper movable regulating plate 2141 and the lower fixed plate 2142, the size of the vents on the upper movable regulating plate 2141 and the lower fixed plate 2142 can be changed to control the air volume entering the radiation plate and adjust the temperature inside the baking channel 23.

[0026] The heat source structure 30 includes a burner 31, a combustion tube 32, and a gas premixing chamber 33. The combustion tube 32 includes an inner tube and an outer tube. The two ends of the inner tube of the combustion tube 32 are respectively connected to the burner 31 and the gas premixing chamber 33. One end of the outer tube of the combustion tube 32 is connected to the gas premixing chamber 33.

[0027] The heat circulation structure 40 includes a return air channel 41, a radiation circulation fan 42, a humidity sensor 52 and an actuator. The radiation circulation fan 42 is provided with an exhaust valve 420, and the actuator controls the exhaust valve 420. The return air channel 41 is connected to the radiation circulation fan 42. The humidity sensor 52 and the actuator are installed on the radiation circulation fan 42. The humidity sensor 52 is electrically connected to the actuator, and the humidity sensor 52 monitors the humidity in the radiation circulation fan 42. When the overall air pressure or humidity reaches a preset value, the actuator controls the exhaust valve 420 to open and discharge part of the circulating gas; when the air pressure or humidity is less than the preset value, the actuator controls the exhaust valve 420 to close. The radiation circulation fan 42 is also provided with a damper for controlling the amount of cold air passing through and returning.

[0028] The control device includes an over-temperature sensing probe 51 and a temperature sensing probe 53. The over-temperature sensing probe 51 is installed in the gas premixing chamber 33 and monitors the temperature in the gas premixing chamber 33 to prevent the heat source structure 30 from being damaged by excessive temperature. The temperature sensing probe 53 monitors the temperature at the air inlet of the air inlet regulating device 214 to control the air inlet regulating device 214, thereby adjusting the temperature of the baking channel 23 to bake different products.

[0029] When the tunnel oven 100 is used, the food to be baked is placed in the baking channel 23. The burner 31 of the heat source structure 30 generates hot air when it works, and flows into the gas premixing chamber 33 through the inner cylinder of the combustion tube 32. The radiation circulation fan 42 drives the reflux cooling gas to flow into the gas premixing chamber 33 through the gap between the outer cylinder and the inner cylinder of the combustion tube 32, and after mixing with the hot air to balance the temperature, it enters the heat exchange channel 213 of the radiation plate assembly 21 through the bottom of the gas premixing chamber 33. During the flow of air in the heat exchange channel 213, the radiation plate assembly 21 radiates heat to the baking channel 23. Due to the radiation plate assembly 21 arranged in parallel and opposite, the conveyor belt also conducts heat at the same time, so that the product is baked. In this process, the observation window 12 can observe the product, and the temperature sensing probe 53 monitors the temperature of the fan inlet, so that the control device can adjust the temperature of the baking channel 23 to bake different products. By adjusting the size of the vent hole of the air inlet adjustment device 214, the air volume entering the radiation plate is controlled, and the temperature inside the baking channel 23 is adjusted. The air flow passing through the radiation panel assembly 21 has its temperature reduced and flows from the return air channel 41 into the radiation circulation fan 42, and then flows from the radiation circulation fan 42 through the outer tube of the combustion tube 32 into the gas premixing chamber 33 and mixes with the hot gas to form a circulation.

[0030] In the above design, the two radiation plate assemblies 21 can radiate heat, and the conveyor belt can conduct heat. Compared with the heating method based on heat convection, it is more energy-saving, has high energy utilization rate and better temperature stability. It is also possible to use the heating method based on radiation and heat convection as an auxiliary method to achieve a better effect.

[0031] For those skilled in the art, various other corresponding changes and deformations can be made according to the technical solutions and concepts described above, and all of these changes and deformations should fall within the protection scope of the claims of the present invention.

Claims

1. A tunnel furnace, characterized in that: The invention comprises a shell, a heat source structure, a baking structure and a heat circulation structure, wherein the heat source structure, the baking structure and the heat circulation structure are fixedly installed on the shell, the baking structure comprises a radiation plate assembly and a side plate, the radiation plate assembly is composed of a single radiation plate or a plurality of radiation plates spliced ​​together; the radiation plate assembly and the side plate enclose a baking channel, a heat exchange channel is arranged in the radiation plate assembly, one end of the heat exchange channel is connected with the heat circulation structure, and the other end of the heat exchange channel, the heat source structure and the heat circulation structure are connected in sequence, thereby forming a closed loop circulation channel; an exhaust valve for connecting the circulation channel with the outside is arranged on the heat circulation structure; the baking structure also comprises a conveying device, and the conveying device is installed in the baking channel ; The baking channel includes at least two parallel radiation plate assemblies; the radiation plate includes an upper plate, a lower plate and a middle partition rib, the upper plate is fixedly connected to the lower plate, the middle partition rib is located between the upper plate and the lower plate and divides the gap between the upper plate and the lower plate to form the heat exchange channel; an air inlet regulating device is provided on the heat exchange channel, the air inlet regulating device is connected to the heat exchange channel, the air inlet regulating device includes an air inlet bellows, a lower fixed plate, and an upper movable regulating plate, and air vents are provided on the lower fixed plate and the upper movable regulating plate; the upper movable regulating plate is slidably connected to the lower fixed plate; the upper movable regulating plate and the lower fixed plate slide with each other to control the ventilation amount of the air vents.

2. The tunnel furnace according to claim 1, characterized in that: The heat circulation structure includes a return air channel and a radiation circulation fan. The return air channel is connected to the radiation circulation fan, and the heat exchange channel is connected to the return air channel. The radiation circulation fan is provided with a damper for controlling the return air volume.

3. The tunnel furnace according to claim 2, characterized in that: The heat source structure also includes a combustion cylinder; the combustion cylinder includes an inner cylinder and an outer cylinder that are arranged in a sleeve; the inner cylinder is connected to the burner, and the hot gas generated by the burner is sprayed from the inner cylinder to the gas premixing chamber; a gap is formed between the outer cylinder and the inner cylinder, and the gap is connected to the radiation circulation fan, and the cold air in the radiation circulation fan is sprayed to the gas premixing chamber through the gap.

4. The tunnel furnace according to claim 3, characterized in that: The tunnel furnace also includes a control device, which includes an over-temperature sensing probe. The over-temperature sensing probe is installed in the gas premixing chamber and monitors the temperature in the gas premixing chamber to prevent the heat source structure from being damaged by excessive temperature.

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