Dual-mode heating oven based on heat pump

Abstract

The utility model discloses a dual-mode heating oven based on a heat pump, which comprises an oven body and a conveying belt, the conveying belt is arranged in an inner cavity of the oven body along the length direction of the oven body, and the dual-mode heating oven is characterized by further comprising a dual-mode heating unit, a high-temperature enhanced vapor injection heat pump system and a control device, the dual-mode heating unit, the high-temperature enhanced vapor injection heat pump system and the control device are arranged on the box body, and the dual-mode heating unit comprises a gradient infrared heating assembly and a mild convection heating assembly. The signal input ends of the gradient infrared heating assembly, the mild convection heating assembly and the high-temperature enhanced vapor injection heat pump system are electrically connected with the corresponding signal output ends of the control device. The dual-mode heating oven can be adapted to heating of various materials through switching of dual-mode heating, so that uniform activation and accurate temperature control are ensured, and the yield and the production efficiency are effectively improved.

Description

Technical Field

[0001] This utility model relates to the field of shoemaking equipment, and in particular to a dual-mode heating oven based on a heat pump. Background Technology

[0002] In shoe manufacturing, the activation and drying of adhesives on the material surface are crucial processes that determine the bonding strength and molding quality of the product. Traditional drying ovens mostly use electric heating tubes, steam, or gas for direct heating, relying on high-temperature hot air to achieve solvent evaporation and adhesive cross-linking and curing. Although such equipment has a simple structure, it suffers from the problem of a single heating method, making it unsuitable for different material characteristics. For high-temperature resistant materials, it is prone to surface overheating and skin formation, and insufficient internal adhesive activation. For sensitive materials, it is prone to causing burns, deformation, and aging, resulting in a low product qualification rate. Furthermore, heating and dehumidification are independent, with high-temperature exhaust air being directly discharged, and waste heat cannot be recovered, resulting in low overall energy efficiency, high energy consumption, and high operating costs.

[0003] With increasing demands for energy conservation, some manufacturers are beginning to replace traditional heating methods with a combination of conventional heat pumps and heated ovens. Conventional heat pumps can recover low-temperature waste heat and are highly energy efficient under medium- and low-temperature conditions. However, when used for high-temperature drying conditions above 100°C required for adhesive activation, they suffer from problems such as high compression ratio, significant heat output attenuation, and insufficient operational stability, making them unsuitable for continuous production requirements. Meanwhile, existing heated ovens are mostly single-function and have poor material adaptability: ovens using infrared radiation have high heating efficiency and strong penetration, but they easily damage sensitive materials that are not radiation-resistant; ovens using pure electric convection heating provide gentler heating, but are slow to heat up, have high energy consumption, and weak dehumidification capabilities. Neither type can flexibly switch heating methods according to material characteristics, and both generally suffer from uneven adhesive activation, low temperature control accuracy, easy damping, and insufficient curing, failing to meet the footwear industry's requirements for high-temperature, high-efficiency, energy-saving, stable, and multi-material compatible adhesive activation and drying. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a dual-mode heating oven based on a heat pump. This dual-mode heating oven can adapt to the heating of various materials by switching between dual heating modes, thereby ensuring uniform activation, precise temperature control, and effectively improving yield and production efficiency.

[0005] To solve the above technical problems, the following technical solution is adopted:

[0006] A dual-mode heating oven based on a heat pump includes a chamber and a conveyor belt, the conveyor belt being arranged in the inner cavity of the chamber along its length. The oven is characterized by further including a dual-mode heating unit, a high-temperature vapor injection enthalpy-increasing heat pump system, and a control device. The dual-mode heating unit, the high-temperature vapor injection enthalpy-increasing heat pump system, and the control device are respectively mounted on the chamber. The dual-mode heating unit includes a gradient infrared heating component and a mild convection heating component. The signal input terminals of the gradient infrared heating component, the mild convection heating component, and the high-temperature vapor injection enthalpy-increasing heat pump system are electrically connected to the corresponding signal output terminals of the control device.

[0007] The aforementioned dual-mode heating oven allows for selection of different heating modes based on the characteristics of various materials. For high-temperature and radiation-resistant materials, a gradient infrared heating component is used in conjunction with a high-temperature jet enthalpy-increasing heat pump system for synergistic drying. As the material is conveyed by a conveyor belt, infrared gradient heating activates the material layer by layer from the inside out, ensuring complete cross-linking and curing of the adhesive. The heat pump system, operating synchronously throughout the process, continuously circulates and removes humid air from the oven cavity, reducing ambient humidity, accelerating solvent diffusion, significantly shortening the overall activation time, and recovering some waste heat to improve overall system efficiency. For materials that are not heat-resistant, a gentle convection heating component is used as the main heat source, supplemented by a high-temperature jet enthalpy-increasing heat pump system for drying. As the material is conveyed by a conveyor belt, the gentle convection heating component provides gentle and uniform heating, avoiding damage to sensitive materials from infrared radiation. The heat pump system operates synchronously, providing basic hot air circulation and efficient dehumidification to maintain a low-humidity environment in the drying chamber. This balance between gentle heating and efficient dehydration is achieved while ensuring material safety and improving drying rate and energy efficiency. This dual-mode heating oven can heat materials according to their characteristics, achieving uniform activation, rapid dehumidification, low energy consumption, and precise temperature control, effectively improving yield and production efficiency.

[0008] The aforementioned control devices generally employ microcomputer controllers.

[0009] In a preferred embodiment, the gradient infrared heating assembly includes at least one first lamp group, at least one second lamp group, and at least one tungsten filament lamp group. The first lamp group, the second lamp group, and the tungsten filament lamp group are sequentially arranged above the conveyor belt along the conveying direction of the conveyor belt, with the second lamp group located behind the first lamp group and the tungsten filament lamp group located behind the second lamp group. The first lamp group includes at least one near-infrared lamp, the second lamp group includes at least one mid-infrared lamp, and the tungsten filament lamp group includes at least one tungsten filament lamp. As the material is conveyed along the conveyor belt from front to back, the gradient infrared heating component sequentially performs three-stage gradient heating on the material: near-infrared, mid-infrared, and tungsten filament lamp stages. This achieves gradient activation from the inside out. First, in the near-infrared stage, the high penetrability of near-infrared light penetrates deep into the material, stimulating the movement of deep water molecules and promoting rapid evaporation and initial activation of the internal solvent. Subsequently, in the mid-infrared stage, mid-infrared light is used to heat the surface of the material over a large area, accelerating the evaporation of the solvent on the material surface, thus forming a synergistic evaporation channel between the inside and outside. Finally, in the tungsten filament lamp stage, high-intensity thermal radiation completes the final powerful activation, achieving complete cross-linking and curing of the adhesive.

[0010] In a further preferred embodiment, the near-infrared lamp tube is a high-efficiency semi-gold-plated near-infrared lamp tube. The semi-gold-plated near-infrared lamp tube achieves directional, high-efficiency, and energy-saving characteristics, allowing for faster evaporation and initial activation of the internal solvent. The aforementioned high efficiency refers to the semi-gold-plated near-infrared lamp tube having an infrared reflectivity ≥ 90%, an electrothermal conversion efficiency ≥ 92%, and a gold plating purity ≥ 99.9%.

[0011] In a preferred embodiment, the gentle convection heating assembly includes multiple heating element groups, each arranged sequentially from front to back above the conveyor belt along its conveying direction. Each heating element group includes at least one heating element. Using heating elements as the main heat source, and with the base hot air provided by the heat pump system, the material is uniformly heated via hot air convection, avoiding damage to sensitive materials from infrared radiation.

[0012] In the preferred embodiment, the high-temperature vapor injection enthalpy-increasing heat pump system includes a vapor injection enthalpy-increasing compressor, a liquid receiver, a filter, a plate heat exchanger, a main expansion valve, an evaporator, a gas-liquid separator, an auxiliary expansion valve, at least one condenser, and at least one hot air circulating fan. The vapor injection enthalpy-increasing compressor, condenser, liquid receiver, main expansion valve, evaporator, auxiliary expansion valve, plate heat exchanger, gas-liquid separator, and hot air circulating fan are respectively mounted on the housing. The exhaust port of the vapor injection enthalpy-increasing compressor is connected to the air inlet of the condenser, the liquid outlet of the condenser is connected to the liquid inlet of the liquid receiver, the liquid outlet of the liquid receiver is connected to the liquid inlet of the filter, the liquid outlet of the filter is connected to the main inlet of the plate heat exchanger, and the main outlet of the plate heat exchanger is divided into two paths. One path connects to the liquid inlet of the evaporator via the main expansion valve, the gas outlet of the evaporator connects to the gas inlet of the gas-liquid separator, and the gas outlet of the gas-liquid separator connects to the gas inlet of the vapor injection enthalpy-enhancing compressor. The other path of the main outlet of the plate heat exchanger connects to the auxiliary inlet of the plate heat exchanger via the auxiliary expansion valve, and the auxiliary outlet of the plate heat exchanger connects to the medium-pressure jet port of the vapor injection enthalpy-enhancing compressor. The housing is equipped with an air duct extending along the length of the inner cavity. The air duct has an air inlet and an air outlet that connect to the inner cavity of the housing. The number of hot air circulation fans and condensers are the same and correspond one-to-one. The exhaust port of the hot air circulation fan corresponds to the corresponding condenser, and the air inlet side of the condenser faces the inner cavity of the housing, while the air outlet side of the condenser faces the air inlet of the air duct.

[0013] In the aforementioned high-temperature vapor injection enthalpy-enhancing heat pump system, the entire system is divided into a two-stage compression structure—main cycle heating and auxiliary cycle vapor injection enthalpy enhancement—through the main expansion valve and auxiliary expansion valve. The main cycle heating is the basic process, including: 1. Compression stage: Low-temperature, low-pressure gaseous refrigerant enters the main compression chamber of the vapor injection enthalpy-enhancing compressor via a gas-liquid separator. After initial compression, it mixes with the enthalpy-enhancing gas introduced from the medium-pressure jet port, completing secondary compression and outputting high-temperature, high-pressure gaseous refrigerant (up to 120℃); 2. Condensation and heat release stage: High-temperature, high-pressure gaseous refrigerant enters the condenser and is circulated by a hot air circulation fan and air from the housing. 1. Forced convection heat transfer releases heat for adhesive activation, and the refrigerant condenses into a medium-temperature, high-pressure liquid refrigerant; 2. Liquid storage and filtration stage: The liquid refrigerant flows into the liquid storage tank to stabilize the liquid level, and then passes through the filter to remove impurities and moisture; 3. Throttling and evaporation stage: The liquid refrigerant is throttled and depressurized through the main expansion valve, becoming a low-temperature, low-pressure gas-liquid mixture. After entering the evaporator, it absorbs heat from the fresh air / return air environment and completely evaporates into a low-temperature, low-pressure gaseous refrigerant; 4. Gas return protection stage: The gaseous refrigerant flows through the gas-liquid separator, and after separating the residual liquid, it returns to the inlet of the jet enthalpy-enhancing compressor to complete one main cycle. The auxiliary circuit jet enthalpy enhancement process is a high-temperature performance enhancement process, which includes: 1. Diversion and liquid intake: A portion of the medium-temperature, high-pressure liquid refrigerant is drawn from the liquid receiver and enters the auxiliary circuit expansion valve through the plate heat exchanger; 2. Auxiliary circuit throttling: The liquid refrigerant is throttled through the auxiliary circuit expansion valve and becomes a low-temperature, low-pressure gas-liquid mixture; 3. Plate heat exchange: The auxiliary circuit refrigerant re-enters the plate heat exchanger through the auxiliary circuit of the plate heat exchanger, absorbs heat from the main circuit liquid refrigerant, and completely evaporates into low-temperature, low-pressure gaseous refrigerant. Simultaneously, the main refrigerant is cooled, increasing its subcooling and enhancing its subsequent evaporation heat absorption capacity; 4. Vapor injection enthalpy enhancement: The auxiliary gaseous refrigerant enters the intermediate compression chamber through the compressor's medium-pressure injection port, mixing with the refrigerant in the main compression chamber, increasing the exhaust temperature and heating capacity after compression, reducing the compression ratio, and improving system energy efficiency; 5. Energy recovery: The plate heat exchanger achieves heat recovery, providing a gas source for vapor injection enthalpy enhancement and increasing the subcooling of the main refrigerant, enabling the system to maintain high-efficiency operation under high-temperature conditions. This high-temperature vapor injection enthalpy enhancement heat pump system is specifically designed for high-temperature drying scenarios such as shoe material glue activation. The system can stably output heat at a maximum condensing temperature of 120℃, and features high-efficiency heating, energy-saving operation, and safety and reliability.The system employs a two-stage compression structure of "main circulation heating + auxiliary jet enthalpy enhancement," offering several advantages over ordinary compressors: 1. Stable high-temperature heating capacity: At a condensing temperature of 120℃, the jet enthalpy enhancement design prevents a sudden drop in heating capacity, ensuring continuous and stable high-temperature output; 2. Superior energy efficiency: Two-stage compression combined with plate heat exchanger energy recovery maintains the system's COP at 2.8~3.0, achieving energy savings of over 15% compared to ordinary high-temperature heat pumps; 3. Safe and reliable operation: The gas-liquid separator and jet enthalpy enhancement structure effectively prevent liquid slugging; dual electronic expansion valves provide independent control, allowing for flexible load adjustment to adapt to different drying needs; 4. Strong adaptability: The main / auxiliary flow rate can be precisely adjusted according to operating conditions such as chamber temperature and adhesive application amount, achieving rapid heating and precise temperature control.

[0014] Both the main expansion valve and the auxiliary expansion valve mentioned above are electronic expansion valves.

[0015] In a further preferred embodiment, the air duct includes a top pipe located above the inner cavity of the housing and two side pipes located on both sides of the inner cavity of the housing. The top pipe and the two side pipes are interconnected and together form an air duct with a U-shaped cross-section. The air duct has multiple air inlets and outlets, with the air inlets located on the inner side of the side pipes and the air outlets located on the top pipe. The air duct also has multiple condensers and hot air circulation fans. Each condenser is located on the inner side of the side pipe along its length, with the air inlet side of the condenser facing the inner cavity of the housing and the air outlet side of the condenser facing the air inlet of the air duct. The exhaust port of the hot air circulation fan is located inside the side pipe and aligned with the air inlet of the air duct. With this setup, the hot air circulation fan can draw air from the inner cavity of the chamber to the condenser. The condenser heats the air through forced convection. The heated air is then blown back into the inner cavity of the chamber through the top pipe along the air duct, blowing directly onto the material from above. After contacting the material, the air disperses to both sides and is then drawn back away by the hot air circulation fan through the side pipe, creating a continuous cycle.

[0016] In a further preferred embodiment, a sight glass is installed on the pipe connecting the outlet of the filter to the main inlet of the plate heat exchanger. By installing the sight glass, the refrigerant level and flow state can be directly observed, which is used to determine whether the refrigerant charge in the system is appropriate. Typically, the level should be maintained between 1 / 2 and 2 / 3 of the capacity to avoid overcharging or undercharging.

[0017] The beneficial effects of this utility model are as follows: This dual-mode heating oven can adapt to the heating of various materials by switching between dual-mode heating, thereby ensuring uniform activation and precise temperature control, and effectively improving the yield and production efficiency. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the dual-mode heating oven in an embodiment of the present invention;

[0019] Figure 2 This is a side view of the dual-mode heating oven in an embodiment of the present invention;

[0020] Figure 3 This is a partial sectional view of the dual-mode heating oven in an embodiment of this utility model from top view;

[0021] Figure 4 This is a bottom view of the dual-mode heating oven in an embodiment of this utility model;

[0022] Figure 5 This is a connection diagram of the high-temperature jet enthalpy-enhancing heat pump system in an embodiment of this utility model. Detailed Implementation

[0023] The present invention will be further described below with reference to the accompanying drawings and specific embodiments:

[0024] like Figure 1-5 The diagram shows a dual-mode heating oven based on a heat pump, comprising a chamber 1, a conveyor belt 2, a dual-mode heating unit, a high-temperature vapor injection enthalpy-increasing heat pump system, and a control device (not shown in the diagram). The conveyor belt 2 is arranged in the inner cavity of the chamber 1 along the length of the chamber 1. The dual-mode heating unit, the high-temperature vapor injection enthalpy-increasing heat pump system, and the control device are respectively mounted on the chamber 1. The dual-mode heating unit includes a gradient infrared heating component 3 and a mild convection heating component 4. The signal input terminals of the gradient infrared heating component 3, the mild convection heating component 4, and the high-temperature vapor injection enthalpy-increasing heat pump system are electrically connected to the corresponding signal output terminals of the control device.

[0025] When using the above-mentioned dual-mode heating oven, different heating modes can be selected according to the different characteristics of the materials 5. For materials 5 that are resistant to high temperature and radiation, a gradient infrared heating component 3 is used in conjunction with a high-temperature jet enthalpy-increasing heat pump system for synergistic drying. When the materials 5 are conveyed by the conveyor belt 2, the infrared gradient heating method is used to achieve layer-by-layer activation of the materials 5 from the inside out, ensuring that the glue is completely cross-linked and cured. In addition, the heat pump system, which is turned on synchronously throughout the process, continuously circulates and removes the humid air in the inner cavity of the chamber 1, reduces the ambient humidity, accelerates the solvent diffusion rate, significantly shortens the overall activation time, and recovers some waste heat, thereby improving the overall energy efficiency of the system. For materials 5 that are not resistant to high temperatures, a gentle convection heating component 4 is used as the main heat source, with a high-temperature jet enthalpy-increasing heat pump system for auxiliary drying. While material 5 is conveyed by the conveyor belt 2, the gentle convection heating component 4 provides gentle and uniform heating, avoiding damage to the sensitive material 5 from infrared radiation. The heat pump system operates simultaneously, providing basic hot air circulation and efficient dehumidification to maintain a low-humidity environment in the drying chamber. This ensures the safety of the material 5 while improving the drying rate and energy efficiency, thus achieving a balance between gentle heating and efficient dehydration. This dual-mode heating oven can be specifically heated according to the characteristics of different materials 5, achieving uniform activation, rapid dehumidification, low energy consumption, and precise temperature control for various materials, effectively improving yield and production efficiency.

[0026] The aforementioned control device employs a microcomputer controller.

[0027] The gradient infrared heating assembly 3 includes three first lamp groups 301, one second lamp group 302, and one tungsten filament lamp group 303. The first lamp groups 301, the second lamp groups 302, and the tungsten filament lamp group 303 are arranged sequentially above the conveyor belt 2 along the conveying direction of the conveyor belt 2, with the second lamp group 302 located behind the first lamp group 301 and the tungsten filament lamp group 303 located behind the second lamp group 302. The first lamp group 301 includes multiple high-efficiency semi-gold-plated near-infrared lamps, the second lamp group 302 includes multiple mid-infrared lamps, and the tungsten filament lamp group 303 includes multiple tungsten filament lamps. As material 5 is conveyed along conveyor belt 2 from front to back, the gradient infrared heating component 3 sequentially performs three-stage gradient heating on material 5: near-infrared stage, mid-infrared stage, and tungsten filament lamp group 303 stage. This achieves gradient activation from the inside out. First, in the near-infrared stage, utilizing the high penetration of near-infrared light, the semi-gold-plated near-infrared lamp tube can achieve directional, efficient, and energy-saving heating, penetrating deep into the interior of material 5 to stimulate the movement of deep water molecules and promote rapid evaporation and initial activation of the internal solvent. Subsequently, in the mid-infrared stage, the mid-infrared light is used to heat the surface of material 5 over a large area, accelerating the evaporation of the solvent on the surface of material 5, thereby forming a synergistic evaporation channel between the inside and outside. Finally, in the tungsten filament lamp group 303 stage, high-intensity thermal radiation completes the final powerful activation, achieving complete cross-linking and curing of the adhesive. The aforementioned high efficiency refers to the infrared reflectivity of the semi-gold-plated near-infrared lamp tube being ≥ 90%, the electrothermal conversion efficiency being ≥ 92%, and the purity of the gold plating layer being ≥ 99.9%.

[0028] The gentle convection heating assembly 4 includes multiple heating element groups 401, which are arranged sequentially from front to back above the conveyor belt 2 along the conveying direction of the conveyor belt 2. Each heating element group 401 includes multiple heating elements. The heating elements are used as the main heat source, and the material 5 is uniformly heated by hot air convection through the base hot air provided by the heat pump system, avoiding damage to the sensitive material 5 caused by infrared radiation.

[0029] The high-temperature vapor injection enthalpy-increasing heat pump system includes a vapor injection enthalpy-increasing compressor 6, a liquid receiver 7, a filter 8, a sight glass 9, a plate heat exchanger 10, a main expansion valve 11, an evaporator 12, a gas-liquid separator 13, an auxiliary expansion valve 14, multiple condensers 15, and multiple hot air circulating fans 16. The hot air circulating fan 16 is respectively installed on the housing 1; the exhaust port of the jet enthalpy-enhancing compressor 6 is connected to the air inlet of the condenser 15, the liquid outlet of the condenser 15 is connected to the liquid inlet of the liquid receiver 7, the liquid outlet of the liquid receiver 7 is connected to the liquid inlet of the filter 8, the liquid outlet of the filter 8 is connected to the main inlet of the plate heat exchanger 10, and the sight glass 9 is installed on the pipe connecting the liquid outlet of the filter 8 and the main inlet of the plate heat exchanger 10. The main outlet of the heat exchanger 10 is divided into two paths. One path connects to the liquid inlet of the evaporator 12 via the main expansion valve 11. The gas outlet of the evaporator 12 is connected to the gas inlet of the gas-liquid separator 13, and the gas outlet of the gas-liquid separator 13 is connected to the gas inlet of the vapor injection enthalpy-enhancing compressor 6. The other path of the main outlet of the plate heat exchanger 10 is connected to the auxiliary inlet of the plate heat exchanger 10 via the auxiliary expansion valve 14. The outlet is connected to the medium-pressure jet port of the jet enthalpy-enhancing compressor 6; the housing 1 is provided with an air duct 17 extending along the length of the inner cavity. The air duct 17 has an air inlet and an air outlet that connect to the inner cavity of the housing 1. The number of hot air circulating fans 16 and condensers 15 are the same and correspond one-to-one. The exhaust port of the hot air circulating fan 16 corresponds to the corresponding condenser 15, and the air inlet side of the condenser 15 faces the inner cavity of the housing 1, and the air outlet side of the condenser 15 faces the air inlet of the air duct 17.

[0030] In the aforementioned high-temperature vapor injection enthalpy-increasing heat pump system, the entire system is divided into a two-stage compression structure—main cycle heating and auxiliary vapor injection enthalpy-increasing—through the main expansion valve 11 and the auxiliary expansion valve 14. The main cycle heating is the basic process, including: 1. Compression stage: Low-temperature, low-pressure gaseous refrigerant enters the main compression chamber of the vapor injection enthalpy-increasing compressor 6 via the gas-liquid separator 13. After initial compression, it mixes with the enthalpy-increasing gas introduced from the medium-pressure jet port, completing secondary compression and outputting high-temperature, high-pressure gaseous refrigerant (up to 120℃); 2. Condensation and heat release stage: High-temperature, high-pressure gaseous refrigerant enters the condenser 15 and is circulated by the hot air circulation fan 16 and the air in the housing 1. 1. Forced convection heat exchange: The gas releases heat for adhesive activation and condenses into a medium-temperature, high-pressure liquid refrigerant. 2. Liquid storage and filtration stage: The liquid refrigerant flows into the liquid receiver 7 to stabilize the liquid level, and then passes through the filter 8 to remove impurities and moisture. 3. Throttling and evaporation stage: The liquid refrigerant is throttled and depressurized by the main expansion valve 11, becoming a low-temperature, low-pressure gas-liquid mixture. After entering the evaporator 12, it absorbs heat from the fresh air / return air environment and completely evaporates into a low-temperature, low-pressure gaseous refrigerant. 4. Gas return protection stage: The gaseous refrigerant flows through the gas-liquid separator 13. After separating the residual liquid, it returns to the inlet of the jet enthalpy compressor 6 to complete one main cycle. The auxiliary path jet enthalpy enhancement process is a high-temperature performance enhancement process, including: 1. Diversion and liquid intake: A portion of the medium-temperature, high-pressure liquid refrigerant is drawn from the liquid receiver 7 and enters the auxiliary path expansion valve 14 through the plate heat exchanger 10; 2. Auxiliary path throttling: The liquid refrigerant is throttled by the auxiliary path expansion valve 14, becoming a low-temperature, low-pressure gas-liquid mixture; 3. Plate heat exchange: The auxiliary path refrigerant re-enters the plate heat exchanger 10 through the auxiliary path, absorbing heat from the main path liquid refrigerant and completely evaporating into a low-temperature, low-pressure gas. The system employs a combination of two methods: 1) **Gas-injection enthalpy enhancement:** The auxiliary gaseous refrigerant is cooled, increasing its subcooling and enhancing subsequent evaporation heat absorption capacity. 2) **Vacuum-based enthalpy enhancement:** The auxiliary gaseous refrigerant enters the intermediate compression chamber through the compressor's medium-pressure nozzle, mixing with the refrigerant in the main compression chamber. This increases the exhaust temperature and heating capacity after compression, reduces the compression ratio, and improves system efficiency. 3) **Energy recovery:** The plate heat exchanger 10 recovers cold energy, providing a gas source for vapor-based enthalpy enhancement and increasing the subcooling of the main refrigerant, ensuring efficient system operation even under high-temperature conditions. This high-temperature vapor-based enthalpy enhancement heat pump system is specifically designed for high-temperature drying scenarios such as shoe material glue activation. The system can stably output heat at a maximum condensing temperature of 120°C, combining high-efficiency heating, energy-saving operation, and safety and reliability.The system employs a two-stage compression structure of "main circulation heating + auxiliary jet enthalpy enhancement," offering several advantages over ordinary compressors: 1. Stable high-temperature heating capacity: At a condensing temperature of 120℃, the jet enthalpy enhancement design prevents a sudden drop in heating capacity, ensuring continuous and stable high-temperature output; 2. Superior energy efficiency: Two-stage compression combined with plate heat exchanger energy recovery maintains the system's COP at 2.8~3.0, achieving energy savings of over 15% compared to ordinary high-temperature heat pumps; 3. Safe and reliable operation: The gas-liquid separator 13 + jet enthalpy enhancement structure effectively prevents liquid slugging; dual electronic expansion valves provide independent control, allowing for flexible load adjustment to adapt to different drying needs; 4. Strong adaptability: The main / auxiliary flow rate can be precisely adjusted according to operating conditions such as chamber temperature and adhesive application amount, achieving rapid heating and precise temperature control. The sight glass 9 allows for direct observation of the refrigerant level and flow state, used to determine if the system's refrigerant charge is appropriate. Typically, the level should be maintained between 1 / 2 and 2 / 3 to avoid overcharging or undercharging.

[0031] The air duct 17 includes a top pipe 1701 located above the inner cavity of the housing 1 and two side pipes 1702 located on both sides of the inner cavity of the housing 1. The top pipe 1701 and the two side pipes 1702 are interconnected and together form an air duct 17 with a cross-section in the shape of a door. The air duct 17 has multiple air inlets and outlets. The air inlets of the air duct 17 are located on the inner side of the side pipes 1702, and the air outlets of the air duct 17 are located on the top pipe 1701. Each condenser 15 is located on the inner side of the side pipes 1702 along its length. The air inlet side of the condenser 15 faces the inner cavity of the housing 1, and the air outlet side of the condenser 15 faces the air inlet of the air duct 17. The exhaust port of the hot air circulating fan 16 is located inside the side pipes 1702 and is aligned with the air inlet of the air duct 17. With this setup, the hot air circulating fan 16 can draw the air in the inner cavity of the housing 1 to the condenser 15. The condenser 15 performs forced convection heating on the air. The heated air is then blown back into the inner cavity of the housing 1 through the top pipe 1701 along the air duct 17, and blown directly onto the material 5 from above. After contacting the material 5, the air disperses to both sides and can be drawn back away by the hot air circulating fan 16 through the side pipe 1702, and so on.

Claims

1. A dual-mode heating oven based on a heat pump, comprising a chamber and a conveyor belt, wherein the conveyor belt is disposed within the inner cavity of the chamber along the length of the chamber, characterized in that: It also includes a dual-mode heating unit, a high-temperature jet enthalpy-increasing heat pump system, and a control device. The dual-mode heating unit, the high-temperature jet enthalpy-increasing heat pump system, and the control device are respectively installed on the housing. The dual-mode heating unit includes a gradient infrared heating component and a mild convection heating component. The signal input terminals of the gradient infrared heating component, the mild convection heating component, and the high-temperature jet enthalpy-increasing heat pump system are electrically connected to the corresponding signal output terminals of the control device.

2. The dual-mode heating oven based on a heat pump as described in claim 1, characterized in that: The gradient infrared heating assembly includes at least one first lamp group, at least one second lamp group, and at least one tungsten filament lamp group. The first lamp group, the second lamp group, and the tungsten filament lamp group are sequentially arranged above the conveyor belt along the conveying direction of the conveyor belt, with the second lamp group located behind the first lamp group and the tungsten filament lamp group located behind the second lamp group. The first lamp group includes at least one near-infrared lamp, the second lamp group includes at least one mid-infrared lamp, and the tungsten filament lamp group includes at least one tungsten filament lamp.

3. A dual-mode heating oven based on a heat pump as described in claim 2, characterized in that: The near-infrared lamp tube is a high-efficiency semi-gold-plated near-infrared lamp tube.

4. A dual-mode heating oven based on a heat pump as described in claim 1, characterized in that: The mild convection heating assembly includes multiple heating tube groups, each of which is arranged sequentially from front to back above the conveyor belt along the conveying direction of the conveyor belt, and each heating tube group includes at least one heating tube.

5. A dual-mode heating oven based on a heat pump as described in claim 1, characterized in that: The high-temperature vapor injection enthalpy-increasing heat pump system includes a vapor injection enthalpy-increasing compressor, a liquid receiver, a filter, a plate heat exchanger, a main expansion valve, an evaporator, a gas-liquid separator, an auxiliary expansion valve, at least one condenser, and at least one hot air circulating fan. The vapor injection enthalpy-increasing compressor, condenser, liquid receiver, main expansion valve, evaporator, auxiliary expansion valve, plate heat exchanger, gas-liquid separator, and hot air circulating fan are respectively mounted on the housing. The exhaust port of the vapor injection enthalpy-increasing compressor is connected to the air inlet of the condenser; the liquid outlet of the condenser is connected to the liquid inlet of the liquid receiver; the liquid outlet of the liquid receiver is connected to the liquid inlet of the filter; the liquid outlet of the filter is connected to the main inlet of the plate heat exchanger; and the main outlet of the plate heat exchanger is divided into two paths, one of which... The main expansion valve connects to the liquid inlet of the evaporator, the outlet of the evaporator connects to the inlet of the gas-liquid separator, and the outlet of the gas-liquid separator connects to the inlet of the vapor injection enthalpy-enhancing compressor. Another branch of the main outlet of the plate heat exchanger connects to the auxiliary inlet of the plate heat exchanger via an auxiliary expansion valve, and the auxiliary outlet of the plate heat exchanger connects to the medium-pressure vapor port of the vapor injection enthalpy-enhancing compressor. The housing is equipped with an air duct extending along the length of the inner cavity. The air duct has an inlet and an outlet connecting to the inner cavity of the housing. The number of hot air circulating fans and condensers are the same and correspond one-to-one. The exhaust port of the hot air circulating fan corresponds to the corresponding condenser, and the air inlet side of the condenser faces the inner cavity of the housing, while the air outlet side of the condenser faces the air inlet of the air duct.

6. A dual-mode heating oven based on a heat pump as described in claim 5, characterized in that: The air duct includes a top pipe located above the inner cavity of the housing and two side pipes located on both sides of the inner cavity. The top pipe and the two side pipes are interconnected and together form an air duct with a U-shaped cross-section. There are multiple air inlets and outlets in the air duct. The air inlets are located on the inner side of the side pipes, and the air outlets are located on the top pipe. There are multiple condensers and hot air circulation fans. Each condenser is located on the inner side of the side pipe along its length. The air inlet side of the condenser faces the inner cavity of the housing, and the air outlet side of the condenser faces the air inlet of the air duct. The exhaust port of the hot air circulation fan is located inside the side pipe and is aligned with the air inlet of the air duct.

7. A dual-mode heating oven based on a heat pump as described in claim 5, characterized in that: A sight glass is installed on the pipe connecting the outlet of the filter to the main inlet of the plate heat exchanger.

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