An internal circulating shrinkage furnace

Abstract

The application discloses an inner circulation shrinkage furnace, which comprises a heat preservation shell, an air cavity inner shell, a heater, and a blowing device. The heat preservation shell is internally formed with a mounting channel. The air cavity inner shell is arranged in the mounting channel. The heat preservation shell and the air cavity inner shell form a heating air cavity. The air cavity inner shell is internally formed with a heat shrinkage channel. The side and bottom of the air cavity inner shell are provided with air holes for connecting the heating air cavity and the heat shrinkage channel. The heater is arranged in the heating air cavity for heating air. The blowing device is arranged at the top of the air cavity inner shell for conveying air in the heat shrinkage channel to the heating air cavity, so as to realize the inner circulation of air between the heating air cavity and the heat shrinkage channel. The conveying device is used for conveying products in and out of the heat shrinkage channel. The scheme realizes the inner circulation of hot air in the whole shrinkage furnace, reduces heat dissipation, and further reduces energy waste. Meanwhile, it is easier to control the temperature in the heat shrinkage channel at a target temperature.

Description

Technical Field

[0001] The present application relates to the field of packaging technology, and in particular to an internal circulation shrinkage furnace. Background Art

[0002] Heat shrink film shrinks when exposed to heat, thus tightly wrapping around the product. Based on this characteristic, heat shrink film is widely used in the packaging and transportation of various foods, medicines and daily necessities, and can provide stability, covering and protection for the products.

[0003] On a heat shrink film product packaging line, a heat shrink film is generally first wrapped around the periphery of the product, and then the product is transported to a shrinking furnace for heating via a conveyor belt. The high temperature environment in the shrinking furnace causes the heat shrinkage film to shrink, and then tightly adhere to the periphery of the product. CN203172940U discloses a heat shrink film machine, which utilizes a fan disposed in a hot air furnace to continuously blow hot air from the furnace toward the product to achieve heat shrinkage. However, in this solution, the fan continuously pumps low-temperature air from the environment into the hot air furnace, and the hot air blown onto the surface of the product is directly dissipated into the environment. In addition to being unable to reuse the heated air, resulting in energy waste, it is also difficult to ensure that the temperature of the hot air blown onto the surface of the product can meet the working requirements, affecting the packaging quality. Summary of the Invention

[0004] The purpose of the embodiments of the present invention is to provide an internal circulation shrinking furnace that can solve the above-mentioned problems existing in the prior art.

[0005] To achieve the above objectives, this application adopts the following technical solutions:

[0006] An internal circulation shrinking furnace, comprising:

[0007] The heat-insulating shell has an installation channel formed therein;

[0008] An air cavity inner shell is arranged in the installation channel, a heating air cavity is formed between the heat-insulating shell and the air cavity inner shell, a heat shrinkage channel is formed inside the air cavity inner shell, and air holes are provided on the side and bottom of the air cavity inner shell to connect the heating air cavity and the heat shrinkage channel;

[0009] A heater is provided in the heating air cavity and is used for heating the air;

[0010] An air supply device is provided on the top of the air cavity inner shell, and is used to transport the air in the heat shrink channel to the heating air cavity, thereby realizing internal air circulation between the heating air cavity and the heat shrink channel;

[0011] The conveying device is used to convey the product into and out of the heat shrink channel.

[0012] Optionally, the insulation shell includes an insulation upper shell and an insulation base, the insulation upper shell can be detachably installed on the insulation base, and the air cavity inner shell is installed in the insulation upper shell or the insulation base. The heater and the air supply device can be inspected by opening the insulation upper shell.

[0013] Optionally, one side of the thermal insulation upper shell is hinged to the thermal insulation base via a hinge, and the other side is connected and fixed to the thermal insulation base via a lock. By unlocking the lock, the thermal insulation upper shell can be flipped open.

[0014] Optionally, the air cavity inner shell includes an air cavity upper shell and an air cavity bottom plate, the air cavity upper shell is installed in the thermal insulation upper shell, and the air cavity bottom plate is installed on the thermal insulation base, and by covering the thermal insulation upper shell, the two sides of the air cavity upper shell and the two sides of the air cavity bottom plate are joined to enclose and form the air cavity inner shell.

[0015] Optionally, the air cavity upper shell includes a first air cavity side panel, an air cavity top panel and a second air cavity side panel which are sequentially connected to form a U-shaped structure, a first side air cavity is formed between the first air cavity side panel and the thermal insulation upper shell, a second side air cavity is formed between the second air cavity side panel and the thermal insulation upper shell, and the heater is arranged in the first side air cavity and the second side air cavity.

[0016] Optionally, the air holes are provided on the bottom plate of the air cavity, and a lower air cavity is formed between the bottom plate of the air cavity and the thermal insulation base. The first side air cavity and the second side air cavity are respectively provided with first air volume regulating components on one side close to the lower air cavity. The ventilation volume between the first side air cavity and the second side air cavity and the lower air cavity is respectively adjusted by the first air volume regulating components, thereby adjusting the air output of the air holes on the bottom plate of the air cavity.

[0017] Optionally, the first air cavity side plate and the second air cavity side plate are respectively connected to a support plate extending outward and abutting the inner wall of the thermal insulation upper shell on one side close to the air cavity bottom plate, and ventilation holes are provided on the support plate. The first air volume adjusting component is movably mounted on the support plate, and a first adjustment hole corresponding to the ventilation hole is provided on the first air volume adjusting component. The overlap degree between the first adjustment hole and the ventilation hole is adjusted by moving the first air volume adjusting component, thereby adjusting the ventilation volume between the first side air cavity and the second side air cavity and the lower air cavity.

[0018] Optionally, the air holes are respectively provided on the first air cavity side panel and the second air cavity side panel, and second air volume adjusting components are respectively provided on the inner sides of the first air cavity side panel and the second air cavity side panel, and the air volume of the air holes on the first air cavity side panel and the second air cavity side panel is respectively adjusted by the second air volume adjusting components.

[0019] Optionally, the second air volume adjusting components on both sides are movably mounted on the inner side of the first air cavity side panel or the second air cavity side panel respectively, and the second air volume adjusting components are provided with second adjustment holes corresponding to the air holes. By moving the second air volume adjusting components, the overlap between the second adjustment holes and the air holes is adjusted, thereby adjusting the air output of the air holes on the first air cavity side panel and the second air cavity side panel.

[0020] Optionally, the air supply device includes a connected air guide ring and a fan, the air guide ring is arranged between the air cavity top plate and the thermal insulation upper shell, and the air cavity top plate is provided with a ventilation port corresponding to the air guide ring, the fan draws the air in the heat shrink channel into the air guide ring through the ventilation port, and the air guide ring guides the air into the first side air cavity and the second side air cavity.

[0021] Optionally, a middle partition is provided in the heating air cavity for dividing the heating air cavity into a medium-temperature air cavity and a high-temperature air cavity, and the heater includes a first heating tube arranged in the medium-temperature air cavity and a second heating tube arranged in the high-temperature air cavity; the area in the heat shrinkage channel corresponding to the medium-temperature air cavity is a preheating expansion area, and the area corresponding to the high-temperature air cavity is a high-temperature heat shrinkage area.

[0022] Optionally, the conveying device includes a conveyor mesh belt and two conveyor wheels respectively arranged at both ends of the heating pipe, the two ends of the conveyor mesh belt are mounted outside the two conveyor wheels, and the upper part of the conveyor mesh belt passes through the inside of the heat shrink channel, and the lower part is located below the insulation shell.

[0023] The beneficial effects of the present application are as follows: the present invention provides an internal circulation shrinkage furnace, an air cavity inner shell is arranged in the installation channel of the insulation shell, and a heater is arranged in the heating air cavity between the air cavity inner shell and the insulation shell. When working, the air supply device continuously draws the air in the heat shrinkage channel in the air cavity inner shell into the heating air cavity for heating, and the hot air in the heating air cavity enters the heat shrinkage channel through the air holes arranged on the air cavity inner shell, thereby achieving the purpose of continuously conveying hot air to the heat shrinkage channel and maintaining a constant temperature in the heat shrinkage channel. The product with heat shrink film is conveyed into the heat shrinkage channel by the conveying device for heating and shrinkage, and then the product is output out of the heat shrinkage channel.

[0024] In this solution, air holes are provided on the sides and bottom of the inner shell of the air cavity. The hot air in the heat shrink channel can enter from both sides and the bottom of the heat shrink channel at the same time, ensuring the uniformity of the temperature of the entire heat shrink channel. At the same time, hot air is blown toward the product from all directions, allowing all positions of the heat shrink film on the product to shrink simultaneously, avoiding the occurrence of undesirable phenomena such as wrinkles and uneven shrinkage caused by different shrinkage speeds at different positions of the heat shrink film due to uneven temperature. In addition, the hot air in the heat shrink channel will not be directly dissipated into the environment. The air supply device directly pumps the air in the heat shrink channel back into the heated air cavity for heating, realizing the internal circulation of the hot air in the entire shrinking furnace, reducing heat dissipation, thereby reducing energy waste, and making it easier to control the temperature in the heat shrink channel at the target temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present application is further described in detail below with reference to the accompanying drawings and examples.

[0026] Figure 1 This is one of the three-dimensional structural schematic diagrams of the internal circulation shrinking furnace described in the embodiment of the present application;

[0027] Figure 2 This is the second schematic diagram of the three-dimensional structure of the internal circulation shrinking furnace described in the embodiment of the present application;

[0028] Figure 3 This is a vertical cross-sectional view of the internal circulation shrinkage furnace described in an embodiment of the present application;

[0029] Figure 4 This is a transverse cross-sectional view of the internal circulation shrinkage furnace described in an embodiment of the present application;

[0030] Figure 5 for Figure 4 A magnified schematic diagram of area A in the middle;

[0031] Figure 6 This is a schematic diagram of the internal structure of the internal circulation shrinkage furnace described in an embodiment of the present application.

[0032] In the picture:

[0033] 1. Insulation shell; 11. Insulation upper shell; 12. Insulation base; 13. Hinge; 14. Lock; 2. Machine base; 3. Air cavity inner shell; 31. Air cavity upper shell; 311. First air cavity side panel; 312. Second air cavity side panel; 313. Air cavity top panel; 32. Air cavity bottom panel; 33. Air hole; 34. Middle partition; 4. Conveying device; 5. Air supply device; 51. Fan; 52. Air guide ring; 6. Heater; 7. First air volume regulating component; 8. Second air volume regulating component; 10. Heat shrink channel; 20. Heating air cavity; 201. First side air cavity; 202. Second side air cavity; 203. Lower air cavity. DETAILED DESCRIPTION

[0034] To make the technical problems solved by this application, the technical solutions adopted, and the technical effects achieved more clearly, the technical solutions of the embodiments of this application are further described in detail below. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making any creative efforts shall fall within the scope of protection of this application.

[0035] In the description of this application, unless otherwise expressly specified or limited, the terms "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and can refer to internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0036] In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0037] like Figures 1-6 As shown, this embodiment provides an internal circulation shrinking furnace, comprising:

[0038] The heat-insulating shell 1 has an installation channel formed therein;

[0039] The air cavity inner shell 3 is arranged in the installation channel, a heating air cavity 20 is formed between the thermal insulation shell 1 and the air cavity inner shell 3, a heat shrinkage channel 10 is formed inside the air cavity inner shell 3, and air holes 33 are provided on the side and bottom of the air cavity inner shell 3 to connect the heating air cavity 20 and the heat shrinkage channel 10;

[0040] A heater 6 is provided in the heating air cavity 20 for heating the air;

[0041] The air supply device 5 is provided on the top of the air cavity inner shell 3 and is used to transport the air in the heat shrink channel 10 to the heating air cavity 20, so as to realize the internal circulation of air between the heating air cavity 20 and the heat shrink channel 10;

[0042] The conveying device 4 is used to convey the product into and out of the heat shrink channel 10 .

[0043] Specifically, when the internal circulation shrinkage furnace of this embodiment is working, the air supply device 5 continuously draws the air in the heat shrinkage channel 10 in the air cavity inner shell 3 into the heating air cavity 20 for heating, and the hot air in the heating air cavity 20 enters the heat shrinkage channel 10 through the air holes 33 set on the air cavity inner shell 3, thereby achieving the purpose of continuously supplying hot air to the heat shrinkage channel 10 and maintaining a constant temperature in the heat shrinkage channel 10. The product with the heat shrinkage film is transported to the heat shrinkage channel 10 through the conveying device 4 for heating and shrinkage, and then the product is output from the heat shrinkage channel 10.

[0044] In this solution, air holes 33 are provided on the sides and bottom of the air cavity inner shell 3 at the same time, and the hot air in the heat shrink channel 10 can enter from both sides and the bottom of the heat shrink channel 10 at the same time, ensuring the uniformity of the temperature of the entire heat shrink channel 10, and at the same time achieving the goal of blowing hot air to the product from all directions, so that all positions of the heat shrink film on the product can shrink at the same time, avoiding the occurrence of undesirable phenomena such as wrinkles and uneven shrinkage caused by different shrinkage speeds at different positions of the heat shrink film due to uneven temperature. In addition, the hot air in the heat shrink channel 10 will not be directly dissipated into the environment. The air supply device 5 directly pumps the air in the heat shrink channel 10 back into the heating air cavity 20 for heating, realizing the internal circulation of the hot air in the entire shrinking furnace, reducing heat dissipation, and thus reducing energy waste. At the same time, it is easier to control the temperature in the heat shrink channel 10 at the target temperature. The heat preservation effect of the heat preservation shell 1 can effectively reduce the heat dissipation in the heating air cavity 20, further reducing energy consumption.

[0045] The heater 6 and the air supply device 5 are arranged in the heat-insulating shell 1. When a fault occurs, it is difficult to repair the heater 6 and the air supply device 5. Therefore, this solution takes the following measures to solve this problem:

[0046] The insulation shell 1 includes an insulation upper shell 11 and an insulation base 12. The insulation upper shell 11 can be detachably installed on the insulation base 12. The air cavity inner shell 3 is installed in the insulation upper shell 11 or in the insulation base 12. The heater 6 and the air supply device 5 can be inspected by opening the insulation upper shell 11.

[0047] Specifically, the insulation shell 1 is configured as a detachable insulation upper shell 11 and an insulation base 12. When the internal heater 6 or air supply device 5 needs to be repaired, the insulation upper shell 11 can be directly opened. At this time, the heating air cavity 20 and the heat shrinkage channel 10 are open, and the staff can easily inspect and replace the internal heater 6 and air supply device 5.

[0048] In some embodiments, one side of the insulation upper shell 11 is hinged to the insulation base 12 by a hinge 13, and the other side is connected and fixed to the insulation base 12 by a lock 14. By unlocking the lock 14, the insulation upper shell 11 can be flipped open.

[0049] Specifically, under normal use, the lock 14 locks the insulation upper shell 11 and the insulation base 12, and the insulation upper shell 11 is fixed on the insulation base 12 to ensure the sealing of the insulation shell 1 and avoid air leakage; when maintenance is required, the lock 14 is opened and the insulation upper shell 11 is flipped to the side where the hinge 13 is located, so that the internal components can be repaired. This solution uses a hinge to connect the insulation upper shell 11 and the insulation base 12. When opening the insulation upper shell 11, it is only necessary to simply flip it over, and after the maintenance is completed, the insulation upper shell 11 can be quickly flipped back, which facilitates the rapid opening and closing operation of the insulation upper shell 11. Specifically, compared to disassembling and removing the entire insulation upper shell 11, this method does not require tedious processes such as hoisting and positioning the insulation upper shell 11.

[0050] Furthermore, the internal circulation shrinkage furnace of this solution includes a machine base 2, an insulation base 12 and a conveying device 4 fixedly installed on the machine base 2. After the insulation upper shell 11 is flipped open, the insulation upper shell 11 will not contact the ground and cause impact damage.

[0051] Regarding the structure of the air cavity inner shell 3, refer to Figure 3 The air cavity inner shell 3 includes an air cavity upper shell 31 and an air cavity bottom plate 32. The air cavity upper shell 31 is installed in the thermal insulation upper shell 11, and the air cavity bottom plate 32 is installed on the thermal insulation base 12. By covering the thermal insulation upper shell 11, the two sides of the air cavity upper shell 31 and the two sides of the air cavity bottom plate 32 are joined to enclose and form the air cavity inner shell 3.

[0052] Similarly, the air cavity inner shell 3 adopts a detachable structure. When the heat-insulating upper shell 11 is opened, the air cavity upper shell 31 inside it is opened accordingly, and the air cavity bottom plate 32 is fixed on the heat-insulating base 12. At this time, the air supply device 5 located at the top of the air cavity upper shell 31 is exposed, and the staff can directly inspect the air supply device 5 inside the air cavity upper shell 31. In addition, in normal operation, under the transportation of the conveying device 4, the product passes through the heat shrink channel 10 inside the air cavity inner shell 3, that is, the conveying device 4 must pass through the inside of the air cavity inner shell 3. Specifically, the conveying device 4 must pass above the air cavity bottom plate 32. However, the flipping and opening of the air cavity upper shell 31 of this solution does not drive the movement of the air cavity bottom plate 32. Therefore, when opening the air cavity upper shell 31, there is no need to remove the conveying device 4, which simplifies the disassembly and assembly process for maintenance operations.

[0053] Reference Figure 4The air cavity upper shell 31 comprises a first air cavity side plate 311, an air cavity top plate 313 and a second air cavity side plate 312 connected in sequence to form a U-shaped structure, the first air cavity side plate 311 and the heat preservation upper shell 11 form a first side air cavity 201, the second air cavity side plate 312 and the heat preservation upper shell 11 form a second side air cavity 202, and the heater 6 is arranged in the first side air cavity 201 and the second side air cavity 202.

[0054] The heater 6 is arranged in the first side air cavity 201 and the second side air cavity 202 respectively, which can ensure that the temperature consistency of the air blown from the first side air cavity 201 and the second side air cavity 202 to the heat shrinkage channel 10 is high, the temperature of the product in the heat shrinkage channel 10 is uniform, the whole heat shrinkage film shrinks synchronously, and the problem of wrinkles caused by different local shrinkage speeds is avoided.

[0055] Specifically, the heater 6 comprises a plurality of heating pipes arranged in the first side air cavity 201 and the second side air cavity 202, in order to fix the heating pipes, a plurality of fixing clamps are arranged on the inner side wall of the heat preservation upper shell 11, the heating pipes are installed on the fixing clamps, when the heat preservation upper shell 11 is turned over and opened, the fixing screws of the air cavity upper shell 31 can be removed, the air cavity upper shell 31 is taken out from the heat preservation upper shell 11, and then the heating pipes fixed on the inner wall of the heat preservation upper shell 11 can be easily repaired and replaced.

[0056] Referring to Figures 4-5 The air holes 33 are arranged on the air cavity bottom plate 32, the air cavity bottom plate 32 and the heat preservation bottom 12 form a lower air cavity 203, the first side air cavity 201 and the second side air cavity 202 are respectively provided with first air volume adjusting members 7 on the side close to the lower air cavity 203, the air volume between the first side air cavity 201 and the second side air cavity 202 and the lower air cavity 203 is adjusted through the first air volume adjusting members 7, and then the air volume of the air holes 33 on the air cavity bottom plate 32 is adjusted.

[0057] Among them, the two sides of the lower air cavity 203 are respectively connected to the first side air cavity 201 and the second side air cavity 202. The first side air cavity 201 and the second side air cavity 202 on both sides can be directly used to provide hot air to the lower air cavity 203, so there is no need to set a heater 6 in the lower air cavity 203. At the same time, in order to facilitate the control of the air volume out of the air holes 33 on the air cavity bottom plate 32 located at the bottom of the product, this solution sets a first air volume adjusting component 7 at the connection between the first side air cavity 201 and the second side air cavity 202 and the lower air cavity 203. The air volume entering the lower air cavity 203 is adjusted by the first air volume adjusting component 7, thereby adjusting the air volume out of the air holes 33 on the air cavity bottom plate 32. In this method, the widths of the first side air cavity 201 and the second side air cavity 202 are relatively small, so the size of the first air volume adjusting component 7 is relatively small. Compared with directly setting the air volume adjusting component on the air cavity bottom plate 32, the structure of this method consumes less materials and has lower cost. At the same time, it will not occupy the space on the air cavity bottom plate 32, thereby avoiding interference with the setting of the conveying device 4.

[0058] Regarding the setting method of the first air volume adjusting component 7, in some embodiments, the first air cavity side panel 311 and the second air cavity side panel 312 are respectively connected to a support plate extending outward and abutting the inner wall of the thermal insulation upper shell 11 on one side close to the air cavity bottom plate 32, and ventilation holes are provided on the support plate. The first air volume adjusting component 7 is movably mounted on the support plate, and a first adjustment hole corresponding to the ventilation hole is provided on the first air volume adjusting component 7. The overlap degree of the first adjustment hole and the ventilation hole is adjusted by moving the first air volume adjusting component 7, thereby adjusting the ventilation volume between the first side air cavity 201 and the second side air cavity 202 and the lower air cavity 203.

[0059] Specifically, the support plate not only plays the role of supporting the first air volume adjusting component 7, but also cooperates with the first air volume adjusting component 7 to realize the air volume adjustment function. The greater the overlap between the first adjustment hole and the ventilation hole, the greater the ventilation volume of the first side air cavity 201 and the second side air cavity 202 to the lower air cavity 203. When the first adjustment hole completely avoids the ventilation hole, the ventilation channel of the first side air cavity 201 and the second side air cavity 202 to the lower air cavity 203 is closed. At this time, no hot air is blown towards the product in the lower air cavity 203.

[0060] Among them, the support plate is preferably formed by directly bending the side ends of the first air cavity side plate 311 and the second air cavity side plate 312 outward through a sheet metal process. There is no fixed connection between the support plate and the insulation shell 1, which facilitates the removal of the entire air cavity upper shell 31 from the insulation upper shell 11.

[0061] In order to adjust the movement of the first air volume adjusting component 7, an adjusting screw can be set at one end of the first air volume adjusting component 7, and a nut that cooperates with the adjusting screw is set on the first air volume adjusting component 7. By rotating the adjusting screw, the first air volume adjusting component 7 can be driven to move linearly.

[0062] Furthermore, the air holes 33 are respectively provided on the first air cavity side panel 311 and the second air cavity side panel 312, and second air volume regulating components 8 are respectively provided on the inner sides of the first air cavity side panel 311 and the second air cavity side panel 312, and the air volumes of the air holes 33 on the first air cavity side panel 311 and the second air cavity side panel 312 are respectively adjusted by the second air volume regulating components 8.

[0063] Similarly, the second air volume adjustment member 8 can be used to adjust the air volume on both sides of the product. This allows operators to freely adjust the air volume on both sides and the bottom of the product according to the heating requirements of each part, thereby controlling the temperature of each side of the product and, in turn, the shrinkage speed of the heat shrink film on each side of the product to meet the packaging requirements of products with different structures.

[0064] The working principle of the second air volume adjusting component 8 is the same as that of the first air volume adjusting component 7. The second air volume adjusting components 8 on both sides are movably installed on the inner side of the first air cavity side panel 311 or the second air cavity side panel 312 respectively. The second air volume adjusting component 8 is provided with a second adjustment hole corresponding to the air hole 33. By moving the second air volume adjusting component 8, the overlap degree of the second adjustment hole and the air hole 33 is adjusted, thereby adjusting the air output of the air hole 33 on the first air cavity side panel 311 and the second air cavity side panel 312.

[0065] Specifically, support brackets are provided on the inner sides of the first and second air chamber side panels 311, 312, respectively. The second air volume adjustment member 8 passes through the support brackets and is movably mounted on the first and second air chamber side panels 311, 312. To adjust the movement of the second air volume adjustment member 8, an adjustment screw is provided at one end of the second air volume adjustment member 8. A nut is provided on the second air volume adjustment member 8 to engage with the adjustment screw. Rotating the adjustment screw drives the second air volume adjustment member 8 to move linearly.

[0066] Reference Figure 6 The air supply device 5 includes a connected air guide ring 52 and a fan 51. The air guide ring 52 is arranged between the air cavity top plate 313 and the thermal insulation upper shell 11. The air cavity top plate 313 is provided with a vent corresponding to the air guide ring 52. The fan 51 draws the air in the heat shrink channel 10 into the air guide ring 52 through the vent. The air guide ring 52 guides the air into the first side air cavity 201 and the second side air cavity 202.

[0067] Specifically, the arrangement of the air guide ring 52 can smoothly push air into the first side air cavity 201 and the second side air cavity 202 on both sides, thereby promoting internal air circulation. The air guide ring 52 includes an air gathering ring and a plurality of air guide fins connected to the outer periphery of the air gathering ring. The air gathering ring is provided with a plurality of air outlets on both sides facing the first side air cavity 201 and the second side air cavity 202, respectively. Each air outlet has a corresponding air guide fin on both sides, and all the air guide fins are arranged in a star-shaped pattern. Driven by the fan 51, the air in the heat shrink channel 10 continuously enters the air gathering ring and converges. After the air in the air gathering ring is blown out from the air outlets on both sides thereof, it is continuously diffused into the first side air cavity 201 and the second side air cavity 202 on both sides under the guidance of the air guide fins.

[0068] In some embodiments, the heating air cavity 20 is provided with a middle partition 34 which divides the heating air cavity 20 into a medium-temperature air cavity and a high-temperature air cavity, and the heater 6 includes a first heating tube arranged in the medium-temperature air cavity and a second heating tube arranged in the high-temperature air cavity; the area of ​​the heat shrinkage channel 10 corresponding to the medium-temperature air cavity is a preheating expansion area, and the area corresponding to the high-temperature air cavity is a high-temperature heat shrinkage area.

[0069] Specifically, in existing heat shrink equipment, products wrapped in heat shrink film are typically transported directly into a high-temperature environment for heating and shrinking. However, because the heat shrink film is initially in a relaxed state, it can fold in some areas. When the heat shrink film is directly heated and shrinks as a whole, wrinkles develop in the previously folded areas, affecting the aesthetics of the packaged product. To address this issue, in this embodiment, a preheating expansion zone and a high-temperature shrinking zone are provided within the heat shrinking channel 10. The temperature in the preheating expansion zone has not yet reached the shrinking temperature of the heat shrink film. When the product wrapped in heat shrink film enters the preheating expansion zone, the increased temperature causes the air within the film to expand, causing the film to stretch and expand, eliminating any folds. The product then enters the high-temperature shrinking zone, where the temperature reaches the shrinking temperature of the film. The film then preheats and shrinks, tightly wrapping around the product. The heat shrink film is provided with vents, through which air within the film is discharged during shrinkage. The temperatures of the preheating expansion zone and the high-temperature shrinking zone can be controlled by controlling the power of the first and second heating tubes, respectively.

[0070] Regarding the setting of the conveying device 4, the conveying device 4 includes a conveying mesh belt and two conveying wheels respectively arranged at the two ends of the heating pipe. The two ends of the conveying mesh belt are arranged outside the two conveying wheels, and the upper part of the conveying mesh belt passes through the inside of the heat shrink channel 10, and the lower part is located below the insulation shell 1.

[0071] The conveyor belt has mesh holes, and the hot air blown out from the air holes 33 on the air chamber bottom plate 32 can be blown to the lower surface of the product through the mesh holes. This solution uses a conveyor belt structure to transport products, which has the advantages of simple structure and low cost.

[0072] In the description herein, it should be understood that the terms "upper," "lower," "left," "right," and other positions or relationships are used solely for ease of description and simplified operation, and are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meaning.

[0073] In this specification, reference to terms such as "one embodiment" or "example" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example.

[0074] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0075] The technical principles of the present application have been described above in conjunction with specific embodiments. These descriptions are intended solely to explain the principles of the present application and are not to be construed in any way as limiting the scope of protection of the present application. Based on the explanations herein, those skilled in the art will be able to devise other specific implementations of the present application without inventive effort, and such implementations will fall within the scope of protection of the present application.

Claims

1. An internal circulation shrinkage furnace, characterized in that: include: A heat-insulating shell (1) comprises a heat-insulating upper shell (11) and a heat-insulating base (12), wherein a mounting channel is formed in the heat-insulating shell (1); An air cavity inner shell (3) is arranged in the installation channel, a heating air cavity (20) is formed between the heat-insulating shell (1) and the air cavity inner shell (3), a heat shrinkage channel (10) is formed inside the air cavity inner shell (3), and air holes (33) are provided on the side and bottom of the air cavity inner shell (3) for connecting the heating air cavity (20) and the heat shrinkage channel (10); A heater (6) is provided in the heating air cavity (20) for heating air; wherein the air cavity inner shell (3) comprises an air cavity upper shell (31) and an air cavity bottom plate (32); the air cavity upper shell (31) comprises a first air cavity side plate (311), an air cavity top plate (313) and a second air cavity side plate (312) which are sequentially connected to form a U-shaped structure; a first side air cavity (201) is formed between the first air cavity side plate (311) and the heat-insulating upper shell (11); and the second air cavity side plate (312) is connected to the heat-insulating upper shell (11). (312) and the heat-insulating upper shell (11) form a second side wind cavity (202), and the heater (6) is arranged in the first side wind cavity (201) and the second side wind cavity (202); the air hole (33) is provided on the wind cavity bottom plate (32), and a lower wind cavity (203) is formed between the wind cavity bottom plate (32) and the heat-insulating base (12), and the first side wind cavity (201) and the second side wind cavity (202) are close to the side of the lower wind cavity (203). A first air volume regulating component (7) is respectively provided, and the ventilation volume between the first side air cavity (201) and the second side air cavity (202) and the lower air cavity (203) is respectively adjusted by the first air volume regulating component (7), thereby adjusting the air outlet volume of the air hole (33) on the air cavity bottom plate (32); the first air cavity side plate (311) and the second air cavity side plate (312) are respectively connected to a support plate extending outward and abutting against the inner wall of the thermal insulation upper shell (11) on one side close to the air cavity bottom plate (32), and the support plate is provided with a ventilation hole, and the first air volume regulating component (7) is movably installed on the support plate, and the first air volume regulating component (7) is provided with a first regulating hole corresponding to the ventilation hole, and the overlap between the first regulating hole and the ventilation hole is adjusted by moving the first air volume regulating component (7), thereby adjusting the ventilation volume between the first side air cavity (201) and the second side air cavity (202) and the lower air cavity (203); An air supply device (5) is provided at the top of the air cavity inner shell (3) and is used to transport the air in the heat shrink channel (10) to the heating air cavity (20), thereby realizing internal circulation of air between the heating air cavity (20) and the heat shrink channel (10); A conveying device (4) is used to convey products into and out of the heat shrink channel (10).

2. The internal circulation shrinkage furnace according to claim 1, characterized in that: The heat-insulating upper shell (11) can be detachably mounted on the heat-insulating base (12), and the air cavity inner shell (3) is mounted in the heat-insulating upper shell (11) or in the heat-insulating base (12). The heater (6) and the air supply device (5) can be inspected and maintained by opening the heat-insulating upper shell (11).

3. The internal circulation shrinkage furnace according to claim 2, characterized in that: One side of the heat-insulating upper shell (11) is hinged to the heat-insulating base (12) via a hinge (13), and the other side is connected and fixed to the heat-insulating base (12) via a lock (14). By unlocking the lock (14), the heat-insulating upper shell (11) can be flipped open.

4. The internal circulation shrinkage furnace according to claim 2, characterized in that: The air cavity upper shell (31) is installed in the heat-insulating upper shell (11), and the air cavity bottom plate (32) is installed on the heat-insulating base (12). By covering the heat-insulating upper shell (11), the two sides of the air cavity upper shell (31) and the two sides of the air cavity bottom plate (32) are joined to enclose and form the air cavity inner shell (3).

5. The internal circulation shrinkage furnace according to claim 4, characterized in that: The air holes (33) are respectively provided on the first air cavity side plate (311) and the second air cavity side plate (312), and second air volume regulating components (8) are respectively provided on the inner sides of the first air cavity side plate (311) and the second air cavity side plate (312), and the air volumes of the air holes (33) on the first air cavity side plate (311) and the second air cavity side plate (312) are respectively adjusted by the second air volume regulating components (8).

6. The internal circulation shrinkage furnace according to claim 5, characterized in that: The second air volume regulating components (8) on both sides are movably mounted on the inner side of the first air cavity side plate (311) or the second air cavity side plate (312), respectively. The second air volume regulating component (8) is provided with a second regulating hole corresponding to the air hole (33). By moving the second air volume regulating component (8), the overlap between the second regulating hole and the air hole (33) is adjusted, thereby adjusting the air volume of the air hole (33) on the first air cavity side plate (311) and the second air cavity side plate (312).

7. The internal circulation shrinkage furnace according to claim 4, characterized in that: The air supply device (5) includes a connected air guide ring (52) and a fan (51), wherein the air guide ring (52) is arranged between the air cavity top plate (313) and the heat-insulating upper shell (11), and a ventilation opening corresponding to the air guide ring (52) is provided on the air cavity top plate (313). The fan (51) draws the air in the heat shrink channel (10) into the air guide ring (52) through the ventilation opening, and the air guide ring (52) guides the air into the first side air cavity (201) and the second side air cavity (202).

8. The internal circulation shrinking furnace according to any one of claims 1 to 7, characterized in that: The heating air cavity (20) is provided with a middle partition (34) for dividing the heating air cavity (20) into a medium-temperature air cavity and a high-temperature air cavity; the heater (6) comprises a first heating tube arranged in the medium-temperature air cavity and a second heating tube arranged in the high-temperature air cavity; the area of ​​the heat shrinkage channel (10) corresponding to the medium-temperature air cavity is a preheating expansion area, and the area corresponding to the high-temperature air cavity is a high-temperature heat shrinkage area.

9. The internal circulation shrinking furnace according to any one of claims 1 to 7, characterized in that: The conveying device (4) comprises a conveying mesh belt and two conveying wheels respectively arranged at the two ends of the heating pipe, the two ends of the conveying mesh belt are sleeved outside the two conveying wheels, and the upper part of the conveying mesh belt passes through the interior of the heat shrink channel (10), and the lower part is located below the insulation shell (1).

Images