Warm air duct system and foot warmer

Abstract

The present invention relates to a warm air duct system and a foot warmer. The warm air duct system includes an upper air duct, a lower air duct, an axial flow fan, and a heating tube. The upper air duct and the lower air duct are circular and are arranged opposite to each other vertically. The axial flow fan is disposed in an accommodation cavity between the upper air duct and the lower air duct, and the heating tube is disposed in the accommodation cavity near the lower air duct. The upper air duct is provided with an air inlet, and a plurality of air outlet tracks extending from the center of the lower air duct to the outer periphery of the lower air duct are provided on the inner surface of the lower air duct facing the accommodation cavity. The heating tube is sleeved around the outer periphery formed by the plurality of air outlet tracks with a gap. The warm air duct system further includes a control device. The present invention utilizes the characteristics of the axial flow fan, such as large air volume, small air pressure, and low noise, combined with the air duct structure design of uniform air outlet, and at the same time utilizes the characteristics of the heating tube, such as good safety and uniform heating, combined with the control device to finely control the warm air duct system and the mixing and circulation of warm and cold air, greatly solving the potential safety hazards while obtaining a better user experience and achieving energy-saving and constant temperature.

Description

Technical Field

[0001] The present invention relates to the technical field of small-area heating, and particularly to a warm air duct system and a foot warmer. Background Art

[0002] Due to the climate differences between the north and the south of China, central heating is not implemented in most areas south of the Yangtze River. Usually, a heater using an electric heating method is used to achieve the heating effect. It is understood that for the consideration of moisture discharge and ventilation in the housing construction in the south, the wall thickness is thinner than that in the north and the heat preservation performance is poor. Large-area heating causes great waste of resources. Therefore, small-area heating equipment is deeply loved by southern residents. Small-area heating generally places the feet on the heating equipment and covers the legs with fabric to achieve heating. Existing small-area heating equipment, such as a brazier, uses traditional electric heating wires for heating. Its heat transfer is slow and the heat dissipation is uneven, resulting in a poor user experience. Generally, the power is adjusted through a manual switch, and the operation energy consumption is large. When operating for a long time or encountering abnormal situations such as being covered by foreign objects or foreign objects entering, it is easy to catch fire at high temperatures and cause electric leakage, posing a great safety hazard. Summary of the Invention

[0003] In order to solve the problems of potential safety hazards, poor user experience, and high energy consumption existing in the existing small-area heating equipment, this solution utilizes the characteristics of a large air volume, small air pressure, and low noise of an axial flow fan combined with the air duct structure design of uniform and rapid air outlet to improve the poor user experience; at the same time, it utilizes the characteristics of good safety performance and uniform heating of a heating pipe, and then combines a control device to finely control the air duct system and the cold and warm air mixing cycle, greatly solving the potential safety hazards while solving the defects of poor user experience and high energy consumption.

[0004] The technical solution adopted by the present invention to solve its technical problems is as follows:

[0005] In a first aspect, the present invention provides a warm air duct system, including an upper air duct, a lower air duct, an axial flow fan, and a heating pipe. The upper air duct and the lower air duct are circular and are arranged opposite to each other up and down. The axial flow fan is arranged in the accommodation cavity between the upper air duct and the lower air duct. The heating pipe is arranged in the accommodation cavity close to the lower air duct. The upper air duct is provided with an air inlet. On the inner surface of the lower air duct facing the accommodation cavity, a plurality of air outlet tracks extending from the center of the lower air duct to the outer periphery of the lower air duct are provided. The heating pipe is sleeved around the outer periphery formed by the plurality of air outlet tracks with a gap, so that the cool air entering from the air inlet is blown by the axial flow fan to the lower air duct, guided by the air outlet tracks to flow to the heating pipe, and the warm air heated by the heating pipe diffuses horizontally and orderly to the surroundings along the extension direction of the air outlet tracks through the gap between the upper air duct and the lower air duct. The warm air duct system further includes a control device for controlling the safe operation of the heating pipe and the axial flow fan and ensuring a comfortable experience during operation.

[0006] In a second aspect, the present invention provides a foot warmer for heating a small area of the legs and feet of one or more people, comprising a box body. The box body is formed by a bottom plate and side plates to enclose a receiving space with an upward opening. In the middle of the receiving space, a warm pedal parallel to the bottom plate is installed. Between the warm pedal and the bottom plate, there is a warm air duct system as described in the first aspect. On the warm pedal, a number of through holes arranged radially are provided. The through holes cooperate with the warm air duct system to conduct upward warm air and downward cold air. Above the warm pedal, a key switch is provided. The key switch is connected to the warm air duct system to control the operation of the warm air duct system. The key switch includes several gears with different sound prompts and / or different color prompts. When the foot warmer works, the axial flow fan blows air, the heating tube generates heat, the upper air duct is provided with an air inlet, and the hot air circulates through the cooperation of the upper and lower air ducts to achieve heating. When in use, the legs and feet are placed on the warm pedal, and a fabric is covered on the legs, so that the usage mode is in a nearly closed state, and the hot air conducts internal circulation. Therefore, the heating element can be heated intermittently, and the fan can blow air continuously, achieving an energy-saving and heat-preserving effect, or by maintaining a constant temperature, the heating element reduces its own heating power according to the rising temperature, achieving an energy-saving and constant-temperature effect.

[0007] The beneficial effects of the present invention are as follows:

[0008] In a first aspect, the present invention adopts the design of combining an axial flow fan with a semi-circular air outlet track, so that the warm air has a large flow rate, uniform air outlet, and low noise; and can perform temperature limit control through a control device, enabling the heating tube to be heated intermittently and the fan to blow air continuously, maintaining a constant temperature effect while saving energy. During use, users can obtain a more comfortable experience and achieve energy-saving and constant temperature.

[0009] In a second aspect, the present invention adopts a heating tube combined with a control device to finely control the warm air duct system and the cold and warm air mixed circulation. By automatically monitoring and controlling the temperature, duration, and power during operation, potential safety hazards are eliminated and the user experience is improved. Description of the Drawings

[0010] Figure 1 is an exploded view of the warm air duct system provided by an embodiment of the present invention;

[0011] Figure 2 is a schematic structural diagram of the warm air duct system provided by an embodiment of the present invention;

[0012] Figure 3 is an exploded view of the warm air duct system including a control module provided by an embodiment of the present invention;

[0013] Figure 4 is a semi-sectional schematic view of the foot warmer provided by an embodiment of the present invention.

[0014] Reference Signs:

[0015] 1 - Warm air duct system; 11 - Upper air duct; 12 - Lower air duct; 13 - Axial flow fan; 14 - Heating tube; 111 - Air inlet; 121 - Air outlet track; 122 - Inner surface; 123 - Duct rib; 124 - Arc-shaped ridge; 15 - Control device; 16 - Cavity; 2 - Foot warmer; 21 - Box body; 22 - Bottom plate; 23 - Side plate; 24 - Warm pedal; 25 - Through hole; 26 - Button switch. Detailed implementation manner

[0016] The present invention relates to a small-area heating device, mainly for the southern regions without central heating. The usage scenarios are rich, such as: various types of areas like living rooms, bedrooms, offices, etc. The usage method is that when the user is sitting or resting and working, they place their feet on the product and cover their legs with a fabric to achieve the functions of heating and keeping warm. Compared with traditional heaters, it has the characteristics of insulation, energy saving, waterproof, fast heating, low noise, and strong heat sensation experience.

[0017] The following will further describe the present invention in combination with the attached drawings and specific implementation manners:

[0018] Please refer to Figure 1 、 Figure 2 The present invention provides a warm air duct system 1, including an upper air duct 11, a lower air duct 12, an axial flow fan 13, and a heating tube 14. The upper air duct 11 and the lower air duct 12 are circular and arranged vertically opposite to each other. The axial flow fan 13 is arranged in the accommodation cavity between the upper air duct 11 and the lower air duct 12. The heating tube 14 is arranged in the accommodation cavity close to the lower air duct 12. The upper air duct 11 is provided with an air inlet 111. A plurality of air outlet tracks 121 extending from the center of the lower air duct 12 to the outer periphery of the lower air duct 12 are arranged on the inner surface 122 of the lower air duct facing the accommodation cavity. The heating tube 14 is sleeved around the outer periphery formed by a plurality of air outlet tracks 121 with a gap.

[0019] Specifically, an axial-flow fan 13 and a heating pipe 14 are selected as the main body, and the final heating and heat dissipation functions are completed through the cooperation of the upper and lower air ducts. Compared with traditional heating wires, the heating pipe 14 has the characteristics of fast heating and fast heat dissipation. In the production process of the heating pipe 14, the hollow metal pipe is first straightened, then the metal heating wire is sleeved into the center, and then magnesium oxide powder is poured into the hollow metal pipe. Then, by vibrating back and forth, the heating wire can be kept in the center of the hollow metal pipe. The magnesium oxide powder isolates the heating wire from the hollow metal pipe, thus achieving the effects of waterproofing, insulation, and heat conduction. Only the heating wire is electrified to generate heat, and the hollow metal pipe of the heating pipe only transfers heat and is not electrified, thereby reducing potential safety hazards. The heating pipe 14 has strong plasticity and stable thermal efficiency, and is suitable for the heating method of this product. The axial-flow fan 13 has less noise and is lighter than the turbine fan. By combining the use of the upper and lower air ducts, the air outlet direction is changed by the structure of the lower air duct outlet track 121 to achieve uniform and rapid air outlet. The heating pipe 14 can quickly and uniformly heat the air. The axial-flow fan 13 combined with the upper and lower air duct structures has a combined effect far better than only using the axial-flow fan 13. The main function of the upper and lower air ducts is to effectively blow out the hot air, while sucking in external air and sucking back part of the warm air to achieve a hot air circulation state. The air inlet 111 provided in the upper air duct 11 admits a mixed air. Part of the cold air is the external air coming in from the outside, and the other part is the internal air circulating back through the outlet track 121. Such a circulating heating of the mixed air is very helpful for raising the air temperature and can also achieve an energy-saving effect. The air duct structure is designed in a circular shape, and the air outlet in all directions is more uniform.

[0020] Further, the outlet track 121 is formed by a plurality of air duct ribs 123 integrally provided on the inner surface 122 and evenly extending from the center of the lower air duct 12 to the outer periphery of the lower air duct 12. The inner surface 122 is a semi-arc surface that gradually decreases in height from the center of the lower air duct 12 to the outer periphery to form an arc, and becomes a plane from the middle position close to the center and the outer periphery of the lower air duct 12 to the outer periphery. The air duct rib 123 is an arc-shaped plate erected on the inner surface 122, and the erected height of the arc-shaped plate gradually increases from the center position of the lower air duct 12 to form an arc-shaped ridge 124.

[0021] Specifically, the working mode of the combination of the outlet track 121 and the axial-flow fan 13 is as follows: First, the air enters from the vertical direction of the fan blades of the axial-flow fan 13. When the air hits down to the center position of the inner surface 122 of the lower air duct, there is a curvature. The outlet track 121 can turn the air blown out by the axial-flow fan 13 by 90 degrees, blow the air out along the arc of the outlet track, and still maintain the air pressure of the axial-flow fan 13. Then, the relatively large air volume of the axial-flow fan 13 is guided to the periphery of the heating pipe 14. After being heated by the heating pipe 14, the heat continues to spread evenly in all directions along the horizontal direction of the outlet of the outlet track 121 due to inertia.

[0022] Further, please refer to Figure 3, the warm air duct system 1 further includes a control device 15, which is arranged in the cavity 16 on the connection and combination side of the upper air duct and the lower air duct, and is used to control the safe operation of the heating pipe 14 and the axial flow fan 13 and ensure a comfortable experience during operation. The control device 15 includes a temperature limit control unit for the heating pipe 14, which is used to stop the heating pipe 14 from working when the temperature of the heating pipe 14 exceeds the high temperature threshold, and resume the heating pipe 14 when the temperature of the heating pipe 14 is lower than the low temperature threshold. The control device 15 includes a warm air temperature limit control unit, which is used to adjust the working power of the heating pipe 14 according to the temperature threshold of the diffused warm air or / and control the working power of the heating pipe 14 according to the command of an external switch. The control device 15 includes a time limit control unit, which is used to stop the operation of the heating pipe 14 and the axial flow fan 13 when the single operation duration of the heating pipe 14 exceeds the set duration threshold.

[0023] Specifically, if the temperature of the heating pipe 14 is too high, it is easy to cause the aging and damage of the equipment materials, and it is also easy to have too much heat, which affects the use experience. Therefore, by setting the high and low temperature thresholds of the heating pipe 14, for example, when the PTC monitoring point about 10 mm away from the heating pipe 14 monitors that the heating pipe 14 generates heat exceeding 120 degrees or other preset values, the heating pipe 14 stops generating heat. At this time, the heating pipe 14 is not shut down. When the temperature drops to the lowest threshold, such as 70 or 60 degrees Celsius or other preset values, it will cause a poor user experience. Then the control device 15 controls the heating pipe 14 to resume generating heat through the temperature limit control unit. In addition, if the temperature of the warm air is too high, it may also damage the equipment materials, scald the user or cause a bad experience. By monitoring and controlling the temperature of the warm air, if the warm air temperature exceeds the set highest threshold, the heating pipe 14 is controlled to suspend generating heat. When the warm air temperature is lower than the set lowest threshold, the heating pipe 14 is controlled to resume generating heat. It should be noted that during the operation of the temperature limit control unit, whether the heating pipe 14 is working or not, the axial flow fan 13 remains in the working state. In some cases, the user may walk away and forget to turn off the warm air duct system 1. Therefore, the longest single operation duration of the heating pipe 14 is set. The duration can be set to the default hour or can be set by the user's preference. When the heating pipe runs for the default or set longest duration, the warm air duct system 1 shuts down. If the user needs to continue, it is started manually.

[0024] Furthermore, the control device 15 further includes a fan monitoring unit, which is used to monitor the operation of the axial flow fan 13, and when the axial flow fan 13 stops running, it controls the heating pipe 14 to stop running.

[0025] Specifically, if the fan does not rotate or the fan breaks down, it is relatively dangerous for the heating pipe 14 to continue generating heat. By monitoring the operation of the axial flow fan 13, an additional layer of protection is added, that is, if it is detected that the axial flow fan 13 does not rotate, the heating pipe 14 is controlled to stop generating heat.

[0026] The present invention also provides a foot warmer 2 for heating a small area of the legs and feet of one or more persons, which comprises a box body 21. The box body 21 is formed by a bottom plate 22 and side plates 23 to enclose a receiving space with an upward opening. A warm footrest 24 parallel to the bottom plate is arranged in the middle of the receiving space. A warm air duct system 1 as described above is arranged between the warm footrest 24 and the bottom plate 22. A plurality of through holes 25 arranged in a radial pattern are formed in the warm footrest 24. The through holes 25 are used to cooperate with the warm air duct system 1 for upward flow of warm air and downward flow of cold air. A key switch 26 is arranged above the warm footrest 24. The key switch 26 is connected to the warm air duct system 1 to control the operation of the warm air duct system 1. The key switch 26 includes a plurality of gears with different sound prompts and / or different color prompts.

[0027] Specifically, the key switch 26 of the foot warmer 2 is placed at the central position on the warm footrest 24 and is provided with a gear switch and a gear indicator light. Since it is considered that the product is placed on the ground during use and it is inconvenient for the user to bend down to operate when changing gears, the key switch 26 is designed to be relatively large and in a concave shape, so that the user can use their foot to change gears. The gears are set to a plurality of cyclic gears, including N gears and pause. To make the user operation simple and comfortable, the N gears are generally set to the first gear, the second gear, and the third gear, and are generally set to be accompanied by both light and sound prompts. Different gears display lights of different colors and sound prompts matching the gears (first gear: beep, second gear: beep beep, third gear: beep beep beep). At the same time, the gear has a memory function, and when the power is restored after power-off, it will remember the last used gear. The working process of the foot warmer 2 is as follows: the axial flow fan 13 blows air, the heating tube 14 generates heat, the upper air duct 11 is provided with an air inlet 111, and the warm air circulates through the cooperation of the upper and lower air ducts to achieve heating. The user places their feet on the warm footrest 24 and covers their legs with a fabric. The use mode is in a nearly closed state, and the hot air circulates internally. Therefore, the heating tube 14 can be heated intermittently, and the axial flow fan 13 can blow air continuously to achieve the energy-saving and heat preservation effect, or through a constant temperature, the heating element reduces its own heating power according to the temperature rise to achieve the energy-saving and constant temperature effect.

[0028] It should be noted that the automatic control system of the warm air duct system 1 and the manual control system of the key switch can work simultaneously and complement each other. Since the comfort perception of individual users is different, the combination of the automatic control system and the key system can not only meet the safe and energy-saving operation, but also take into account the personal preferences of different users.

[0029] For those skilled in the art, according to the technical solutions and concepts described above, various corresponding changes and deformations can be made, and all such changes and deformations should fall within the protection scope of the claims of the present invention.

[0030] It should be noted that the above-described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. The singular forms "a", "the", and "its" used in the embodiments and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

Claims

1. A warm air duct system, comprising an upper air duct, a lower air duct, an axial flow fan and a heating pipe, characterized in that, The upper air duct and the lower air duct are circular and arranged vertically opposite to each other. The axial flow fan is arranged in the accommodation cavity between the upper air duct and the lower air duct. The heating pipe is arranged in the accommodation cavity near the lower air duct. The upper air duct is provided with an air inlet. On the inner surface of the lower air duct facing the accommodation cavity, a number of air outlet tracks extending from the center of the lower air duct to the outer periphery of the lower air duct are provided. The heating pipe is sleeved around the outer periphery formed by a number of air outlet tracks with a gap; The air outlet track is formed by a number of air duct ribs integrally arranged on the inner surface and evenly extending from the center of the lower air duct to the outer periphery of the lower air duct; The inner surface is a semi-arc surface that gradually decreases in height from the center of the lower air duct to the outer periphery to form an arc, and is a plane from the middle position close to the center and the outer periphery of the lower air duct to the outer periphery.

2. The warm air duct system according to claim 1, characterized in that, The air duct rib is an arc-shaped plate erected on the inner surface, and the erected height of the arc-shaped plate gradually increases from the center position of the lower air duct to form an arc-shaped ridge.

3. The warm air duct system according to claim 1, characterized in that, The warm air duct system further includes a control device, which is arranged in the cavity on the connection and combination side of the upper air duct and the lower air duct, and is used to control the safe operation of the heating pipe and the axial flow fan and the comfortable experience during operation.

4. The warm air duct system according to claim 3, characterized in that, The control device includes a heating pipe temperature limit control unit, which is used to stop the heating pipe from working when the temperature of the heating pipe exceeds the high temperature threshold and resume the heating pipe working when the temperature of the heating pipe is lower than the low temperature threshold.

5. The warm air duct system according to claim 3, characterized in that, The control device includes a warm air temperature limit control unit, which is used to adjust the working power of the heating pipe according to the diffusion warm air temperature threshold or / and control the working power of the heating pipe according to the instruction of an external switch.

6. The warm air duct system according to claim 3, characterized in that The control device includes a time limit control unit, which is used to stop the operation of the heating pipe and the axial flow fan when the single operation duration of the heating pipe exceeds the set time threshold.

7. The warm air duct system according to claim 3, characterized in that, The control device further includes a fan monitoring unit, which is used to monitor the operation of the axial flow fan, and when the axial flow fan stops running, it controls the heating pipe to stop running.

8. A foot warmer for warming the small areas of the legs and feet of one or more persons, comprising a box body, the box body being formed by a bottom plate and side plates to enclose a receiving space with an upward opening, and a warm pedal parallel to the bottom plate being provided in the middle of the receiving space, characterized in that, A warm air duct system as described in any one of claims 1-7 is provided between the warm pedal and the bottom plate. A number of through holes arranged radially are provided on the warm pedal for cooperating with the warm air duct system for upward warm air and downward cold air. A key switch is provided above the warm pedal. The key switch is connected to the warm air duct system to control the operation of the warm air duct system. The key switch includes a number of gears with different sound prompts and / or different color prompts.

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