An electric heater

Abstract

The electric heater provided by the present invention includes: a housing, which includes a receiving cavity and a heat dissipation opening. The heat dissipation opening is arranged along the side of the housing and is communicated with the receiving cavity; a heating plate, which is arranged inside the receiving cavity and includes a first heating surface and a second heating surface arranged opposite to each other. The first heating surface faces the heat dissipation opening, and the surface emissivity of the first heating surface is higher than that of the second heating surface. By arranging a heating plate with surfaces having different surface emissivities inside the housing, with the side having a high emissivity facing the heat dissipation opening, heat is efficiently transferred to the heating area in the form of thermal radiation, rapidly increasing the temperature of the heating area. The side with a low emissivity faces away from the heat dissipation opening, reducing the heat conducted to the housing and minimizing heat loss, thereby improving the utilization efficiency of heat and achieving high-performance unidirectional heat transfer.

Description

Technical Field

[0001] The present invention relates to the technical field of household appliances, and particularly to an electric heater. Background Art

[0002] As a common heating device in daily life, electric heaters include different types such as PTC electric heaters, radiant electric heaters, oil-filled radiator heaters, and electric film heaters. Among them, the electric film heater uses natural convection heat transfer and radiation heat transfer as principles. Natural convection uses the density difference between hot and cold air as the driving force to drive the indoor air circulation and adjust the indoor temperature. The radiant heat is easily absorbed by the human body and the clothes worn, resulting in good heating effect for the human body and high energy efficiency.

[0003] However, during the heating process of the electric film heater, due to the direct upward floating of the natural convection hot air, the heat is directly transported to the top of the room and cannot be directly transported to the area where people are active. This causes the air temperature in the upper part of the room to be relatively high, while the air temperature in the lower area where people are active is relatively low. The temperature stratification in the vertical direction is obvious, resulting in low heat utilization efficiency and poor thermal comfort for the human body. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defect of low heat utilization efficiency of the electric heater in the prior art, and thus provide an electric heater.

[0005] The present invention provides an electric heater, including:

[0006] A housing, including a receiving cavity and a heat dissipation opening, the heat dissipation opening is arranged along the side of the housing and is communicated with the receiving cavity;

[0007] A heating plate, arranged inside the receiving cavity, including a first heating surface and a second heating surface arranged opposite to each other, the first heating surface faces the heat dissipation opening, and the surface emissivity of the first heating surface is higher than that of the second heating surface.

[0008] The electric heater further includes: a wind guiding cavity, formed between the side of the housing different from the heat dissipation opening and the heating plate;

[0009] An air inlet cavity, arranged at the bottom side of the wind guiding cavity and provided with an air inlet, the air inlet cavity is communicated with the wind guiding cavity, and a cross-flow fan is arranged inside, suitable for providing power for the flow of gas;

[0010] Baffles, respectively arranged on both sides of the heating plate, an air outlet cavity formed by the baffles is formed between the heating plate and the housing, and the air flow entering the wind guiding cavity flows out through the air outlet cavity.

[0011] An air outlet is arranged at a position on the housing corresponding to the air outlet cavity.

[0012] The air outlet is in a slit shape, is arranged in the vertical direction, and is respectively arranged on both sides of the heat dissipation opening.

[0013] The air guiding cavity further includes a deflector plate, and the deflector plate is arranged on the side of the heating plate facing away from the heat dissipation opening.

[0014] The deflector plate is arranged parallel to the heating plate. The side surface of the deflector plate opposite to the heating plate is a reflecting surface. The reflecting surface is adapted to reflect thermal radiation, and the surface emissivity of the reflecting surface is less than the surface emissivity of the first heating surface.

[0015] The electric heater further includes a wind guiding plate, which is arranged in the air inlet cavity, and the upper end of the wind guiding plate is connected to the lower end of the deflector plate.

[0016] A wire mesh cover is arranged at the heat dissipation opening, and the opening rate of the wire mesh cover is not less than 50%;

[0017] A grille is arranged at the air inlet, and the opening rate of the grille is not less than 50%.

[0018] The surface emissivity of the first heating surface is not less than 0.8, the surface emissivity of the second heating surface is not higher than 0.3, and the surface emissivity of the reflecting surface is not higher than 0.3.

[0019] The air outlet cavity and the air guiding cavity are both arranged in a square shape and are perpendicular to each other.

[0020] The technical solution of the present invention has the following advantages:

[0021] 1. The electric heater provided by the present invention includes: a housing, including a receiving cavity and a heat dissipation opening, the heat dissipation opening is arranged along the side of the housing and is communicated with the receiving cavity; a heating plate, arranged inside the receiving cavity, including a first heating surface and a second heating surface arranged opposite to each other, the first heating surface faces the heat dissipation opening, and the surface emissivity of the first heating surface is higher than the surface emissivity of the second heating surface.

[0022] A heating plate with surfaces having different surface emissivities is arranged in the housing. The heating plate faces the heat dissipation opening with the side having a high emissivity, and efficiently transfers heat to the heating area in the form of thermal radiation, quickly increasing the temperature of the heating area. The side with a low emissivity faces away from the heat dissipation opening, reducing the heat conducted to the housing and reducing heat loss, thereby improving the utilization efficiency of heat and realizing high-performance unidirectional heat transfer.

[0023] 2. For the electric heater provided by the present invention, an air outlet is arranged at a position corresponding to the air outlet cavity on the housing.

[0024] Since the air inlet cavity is arranged at the bottom side of the air guiding cavity, and the air outlet cavity is composed of baffles on both sides of the heating plate and is arranged in communication with the air guiding cavity. At the same time, the air inlet and the air outlet cavity are in corresponding positions. Therefore, the air inlet is arranged at the lower end of the air outlet. The air outlet blows out the air flow heated by the heating plate and diffuses it into the surrounding air. And the hot air flow will rise upward under the action of the buoyancy force. Such a setting avoids the hot air flow blown out by the air outlet being sucked into the inside of the electric heater by the cross-flow fan and reheated, but sucks in the air with a lower temperature at the bottom side, thus improving the heating efficiency of the device.

[0025] 3. For the electric heater provided by the present invention, the air outlet is in a slit shape, is arranged in the vertical direction, and is respectively arranged on both sides of the heat dissipation opening.

[0026] With such a setting of the air outlet, the air flow heated by the heating plate blows out from the slit-shaped air outlet. The hot air flow gradually diffuses during the flowing process and exchanges heat with the surrounding cold air to heat the surrounding cold air. Adopting a double-slit type air outlet design, on the one hand, the air outlet is relatively narrow, the air outlet speed is faster, and the hot air flow transfers farther forward, expanding the heating area for people. On the other hand, the setting of multiple air outlets makes the air temperature uniformity in the heating area better, improving the environmental thermal comfort of the personnel activity area.

[0027] 4. For the electric heater provided by the present invention, the deflector is arranged parallel to the heating plate. The side surface of the deflector opposite to the heating plate is a reflecting surface. The reflecting surface is suitable for reflecting thermal radiation, and the surface emissivity of the reflecting surface is less than that of the first heating surface.

[0028] The deflector is arranged opposite to and parallel to the heating plate, forming an air heating flow channel. During the process of guiding the air flow, the air is heated. At the same time, the reflecting surface on the deflector reflects part of the thermal radiation from the second heating surface by increasing the reflectivity and reducing the surface emissivity, reducing the heat absorption of the deflector for thermal radiation, reducing the heat dissipated from the heating plate to the rear shell of the heater, lowering the temperature of the rear shell of the heater, effectively improving the thermal efficiency of the device. In addition, it also supplements the calorific value of the second heating surface with a lower surface emissivity to ensure that the air entering the accommodation cavity is effectively heated.

[0029] 5. For the electric heater provided by the present invention, a mesh cover is arranged at the heat dissipation opening, and the opening ratio of the mesh cover is not less than 50%; a grille is arranged at the air inlet, and the opening ratio of the grille is not less than 50%.

[0030] A mesh cover and a grille are respectively arranged at the heat dissipation opening and the air inlet. Such an arrangement avoids the user from coming into contact with the heating plate or the cross-flow fan, improves the safety of the electric heater, and also prevents the heating plate or the cross-flow fan from coming into contact with the outside world and thus being damaged by bumping. In addition, the opening ratios of the mesh cover and the grille are both not less than 50%. With such an arrangement, on the one hand, the high opening ratio at the heat dissipation opening where the mesh cover is located can increase the heat radiated by the heating plate to the outside world and improve the heating effect on the human body; on the other hand, the high opening ratio at the air inlet where the grille is located can reduce the air inlet resistance and increase the air inlet volume. Brief Description of the Drawings

[0031] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0032] Figure 1 It is a three-dimensional schematic diagram of the electric heater provided in the embodiment of the present invention;

[0033] Figure 2 is Figure 1 a cross-sectional schematic diagram of the electric heater shown;

[0034] Figure 3 is Figure 1 an internal structure schematic diagram of the electric heater shown;

[0035] Figure 4 is Figure 1 an internal structure schematic diagram of the electric heater from another angle shown;

[0036] Figure 5 is Figure 1 a cross-sectional schematic diagram of the electric heater from another angle shown.

[0037] Description of the Reference Numerals:

[0038] 1 - housing; 2 - heating plate; 3 - deflector; 4 - accommodating cavity; 5 - heat dissipation opening; 6 - cross-flow fan; 41 - air guiding cavity; 42 - air inlet cavity; 43 - air outlet cavity; 421 - air inlet; 431 - air outlet; 31 - reflecting surface; 52 - mesh cover; 422 - grille; 21 - first heating surface; 22 - second heating surface. Detailed Embodiments

[0039] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0040] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0041] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0042] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0043] As Figure 1 - Figure 5 As shown, this embodiment provides an electric heater, which includes a housing 1 and a base. The housing 1 is a square housing 1, and two long strip-shaped bearing bases are arranged in parallel on the bottom side.

[0044] The housing 1 includes a receiving cavity 4 and a heat dissipation port 5. Among them, the heat dissipation port 5 is communicated with the receiving cavity 4 and is arranged on the surface of the housing 1 with the largest circumferential area. A mesh cover 52 is arranged on the heat dissipation port 5, and the opening rate of the mesh cover 52 is not less than 50%. The specific form of the mesh cover 52 is not limited and can be circular, diamond-shaped, or waist-shaped hole, etc. In this embodiment, the mesh cover 52 has uniform round holes, and the mesh cover 52 is integrally arranged with the surface of the housing 1. The setting range of the mesh holes is adapted to the size of the heating plate 2, and the occupied area is approximately the same.

[0045] The heating plate 2 is in the shape of a square plate and is fixed inside the accommodation cavity 4. It includes a first heating surface 21 and a second heating surface 22 which are oppositely arranged. The first heating surface 21 faces the heat dissipation port 5, and the heating plate 2 is parallel to the surface of the housing 1 where the heat dissipation port 5 is located. The surface emissivity of the first heating surface 21 is higher than that of the second heating surface 22. Emissivity is a measure of the relative strength of the ability of an object's surface to release energy in the form of radiation. This indicates that during the operation of the heating plate 2, the heat generation amount of the first heating surface 21 per unit time is higher than the radiation heat of the second heating surface 22. In this embodiment, the heating plate 2 is an aluminum alloy heating plate with a high emissivity coating. As other implementation manners, the heating plate 2 can also be composed of electric heating elements such as mica electric heating film, silicon crystal electric heating film, and carbon crystal heating plate. The first heating surface 21 is coated with a high emissivity material, and the surface emissivity ≥ 0.8. The second heating surface 22 uses a low emissivity material, and the surface emissivity ≤ 0.3.

[0046] A heating plate 2 with surfaces having different surface emissivities is arranged inside the housing 1. The heating plate 2 faces the heat dissipation port 5 with the side having a high emissivity, and efficiently transfers heat to the heating area in the form of thermal radiation, quickly increasing the temperature of the heating area. The side with a low emissivity faces away from the heat dissipation port 5, reducing the heat conducted to the housing 1, reducing heat loss, and improving the utilization efficiency of heat, realizing high-performance unidirectional heat transfer.

[0047] As Figure 2 - Figure 4 shown, the inside of the accommodation cavity 4 includes a wind guiding cavity 41, an air inlet cavity 42, and an air outlet cavity 43.

[0048] In this embodiment, the wind guiding cavity 41 is surrounded by the heating plate 2, the flow guiding plate 3, and some baffles. The flow guiding plate 3 is in the shape of a square plate and is arranged on the side of the heating plate 2 facing away from the heat dissipation port 5. The second heating surface 22 of the heating plate 2 faces the inside of the wind guiding cavity 41. Two lateral baffles perpendicular to itself are fixed on the flow guiding plate 3. In addition, two lateral baffles are also arranged on both sides of the heating plate 2. The wind guiding cavity 41 and the air outlet cavity 43 are formed by the flow guiding plate 3, the heating plate 2, and their respective corresponding side plates. The air outlet cavity 43 is arranged on both sides of the wind guiding cavity. The flow guiding plate 3 is arranged parallel to the heating plate 2. The side surface of the flow guiding plate 3 opposite to the second heating surface 22 is a reflecting surface 31. The surface of the reflecting surface 31 uses a low emissivity and high reflectivity material, which can partially reflect thermal radiation. The surface emissivity of the reflecting surface 31 ≤ 0.3, and is simultaneously less than the surface emissivity of the first heating surface 21.

[0049] The flow deflector 3 is arranged opposite to and parallel with the heating plate 2, forming an air heating flow channel. During the process of guiding the air flow, the air is heated. At the same time, the reflecting surface 31 on the flow deflector 3 reflects part of the thermal radiation from the second heating surface 22 by increasing the reflectivity and reducing the surface emissivity, reducing the heat absorption of the flow deflector 3 from the thermal radiation, reducing the heat dissipated from the heating plate 2 to the rear shell of the heater, reducing the temperature of the rear shell of the heater, effectively improving the thermal efficiency of the device. In addition, the heat generation of the second heating surface 22 with a lower surface emissivity is supplemented to ensure that the air entering the accommodation cavity 4 is effectively heated.

[0050] As a transformable embodiment, the flow deflector 3 may not be provided, and the air guiding cavity 41 may be formed by the inner wall of the housing 1 on the side different from the heat dissipation port 5 and the heating plate 2.

[0051] In this embodiment, the air inlet cavity 42 is arranged at the bottom side of the air guiding cavity 41 and is provided with an air inlet 421. The air outlet cavity 43 is arranged on both sides of the air guiding cavity 41 and communicates with the air guiding cavity 41. Air outlets 431 are arranged at corresponding positions on the air outlet cavity 43. The air inlet 421, the air outlets 431 and the heat dissipation port 5 are on the same end face of the housing 1. The air outlets 431 are arranged on both sides of the mesh cover 52, and the air inlet 421 provided with a grille 422 is arranged at the bottom side of the mesh cover 52. As a transformable embodiment, the air outlets 431 and the air outlet cavity 43 may be arranged in a staggered manner and communicated through means such as pipes.

[0052] At the top end of the air inlet cavity 42 on the side opposite to the air inlet 421, there is an air guiding channel communicating with the air guiding cavity 41. The air guiding plate in the air inlet cavity is in a curved surface shape, with its bottom end fixed to the bottom surface of the air inlet cavity and its top end fixed to the lower end of the flow deflector. The air inlet cavity 42 and the air guiding cavity 41 are partially separated by a horizontally arranged bearing plate. The bearing plate is fixed with a heating plate 2 at the end opposite to the heat dissipation port 5. The above settings together form the air guiding channel. A cross-flow fan 6 serving as an air flow power source is also arranged inside the air inlet cavity 42.

[0053] As Figure 3 shown, both the air outlet cavity 43 and the air guiding cavity 41 are arranged as square spaces, perpendicular to each other, and communicate with each other, and present a "concave" shape after communication.

[0054] Since the air inlet cavity 42 is arranged at the bottom side of the air guiding cavity 41, and the air outlet cavity 43 is formed by baffles on both sides of the heating plate 2 and is arranged to communicate with the air guiding cavity 41. At the same time, the air inlet 421 corresponds to the position of the air outlet cavity 43. Therefore, the air inlet 421 is arranged at the lower end of the air outlet 431. The air outlet 431 blows out the air flow heated by the heating plate 2 and diffuses it into the surrounding air. And the hot air flow will rise under the action of the buoyancy force. Such a setting avoids the hot air flow blown out by the air outlet 431 being sucked into the heater by the cross-flow fan 6 and reheated, but sucks in the air with a lower temperature at the bottom side, improving the heating efficiency of the device.

[0055] In this embodiment, the air outlet 431 is in a slit shape, arranged in the vertical direction, and is respectively arranged on both sides of the heat dissipation opening 5. At the same time, the extension length of the air outlet 431 is approximately equal to the extension length of the mesh holes of the mesh cover 52 in the vertical direction. With such a setting of the air outlet 431, the air flow heated by the heating plate 2 is blown out from the slit-shaped air outlet 431. The hot air flow gradually diffuses during the flowing process and exchanges heat with the surrounding cold air, heating the surrounding cold air. By adopting the design of the double-slit air outlet 431, on the one hand, the air outlet 431 is relatively narrow, so the air outlet speed is faster, and the hot air flow can be transmitted farther forward, expanding the heating area for people. On the other hand, the setting of multiple air outlets 431 makes the air temperature uniformity in the heating area better, improving the environmental thermal comfort of the personnel activity area.

[0056] The width of the air outlet 431 is between 1 mm and 4 mm. In this embodiment, the air outlet 431 is a rectangular long hole with a horizontal width of 2.5 mm. As a changeable implementation method, the width of the air outlet 431 can be adaptively adjusted according to factors such as the selection of the cross-flow fan 6. In specific implementation, by adopting the design of the double-slit air outlet, compared with the prior art, the hot air flow can be transmitted farther forward, and the heating range in front of the electric heater is larger. The air temperature at the position 0.8 m away from the electric heater and 0.8 m above the ground is 20.3 °C, which is 2.8 °C higher than that of the upper air outlet design. The air temperature at the position 1.2 m away from the electric heater and 0.8 m above the ground is 0.6 °C higher than that of the upper air outlet design.

[0057] In this embodiment, a mesh cover 52 and a grille 422 are respectively arranged at the heat dissipation opening 5 and the air inlet 421. The opening ratios of the mesh cover 52 and the grille 422 are not less than 50%. Such a setting avoids the user from coming into contact with the heating plate 2 or the cross-flow fan 6, improving the safety of the electric heater, and also avoids the heating plate 2 or the cross-flow fan 6 from coming into contact with the outside and thus being damaged by bumping, etc. In addition, the opening ratios of the mesh cover 52 and the grille 422 are not less than 50%. With such a setting, on the one hand, the high opening ratio at the heat dissipation opening 5 where the mesh cover 52 is located can increase the heat radiated by the heating plate 2 to the outside, improving the heating effect on the human body; on the other hand, the high opening ratio at the air inlet 421 where the grille 422 is located can reduce the air inlet resistance and improve the air inlet volume.

[0058] Obviously, the above embodiments are only examples clearly described and not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or variations can be made based on the above description. It is not necessary and impossible to enumerate all the implementation manners here. And the obvious changes or variations derived therefrom are still within the protection scope of the present invention.

Claims

1. An electric heater, characterized in that, Comprising: A housing (1), including a receiving cavity (4) and a heat dissipation opening (5), the heat dissipation opening (5) being arranged along the side of the housing (1) and communicating with the receiving cavity (4); A heating plate (2), arranged inside the receiving cavity (4), including a first heating surface (21) and a second heating surface (22) arranged opposite to each other, the first heating surface (21) facing the heat dissipation opening (5) and the second heating surface (22) facing away from the heat dissipation opening (5), the surface emissivity of the first heating surface (21) being higher than that of the second heating surface (22); The electric heater further includes: a wind guiding cavity (41), formed between the side of the housing (1) different from the heat dissipation opening (5) and the heating plate (2); An air inlet cavity (42), arranged at the bottom side of the wind guiding cavity (41) and provided with an air inlet (421), the air inlet cavity (42) communicating with the wind guiding cavity (41) and internally provided with a cross-flow fan (6) suitable for providing power for the flow of gas; baffles, respectively arranged on both sides of the heating plate (2), an air outlet cavity (43) formed by the baffles being formed between the heating plate (2) and the housing (1), and the air flow entering the wind guiding cavity (41) flowing out through the air outlet cavity (43).

2. The electric heater according to claim 1, wherein A part of the housing (1) corresponding to the air outlet cavity (43) is provided with an air outlet (431).

3. The electric heater according to claim 2, characterized in that, The air outlet (431) is in a slit shape, arranged in the vertical direction and respectively arranged on both sides of the heat dissipation opening (5).

4. The electric heater according to any one of claims 1 to 3, characterized in that, The wind guiding cavity (41) further includes a guiding plate (3), the guiding plate (3) being arranged on the side of the heating plate (2) facing away from the heat dissipation opening (5).

5. The electric heater according to claim 4, wherein The guiding plate (3) is arranged parallel to the heating plate (2), the side surface of the guiding plate (3) opposite to the heating plate (2) being a reflecting surface (31), the reflecting surface (31) being suitable for reflecting heat radiation, and the surface emissivity of the reflecting surface (31) being less than that of the first heating surface (21).

6. The electric heater according to claim 5, characterized in that, It further includes a wind guiding plate, arranged in the air inlet cavity (42), the upper end of the wind guiding plate being connected to the lower end of the guiding plate (3).

7. The electric heater according to claim 1, wherein A mesh cover (52) is arranged at the heat dissipation opening (5), and the opening ratio of the mesh cover (52) is not less than 50%; A grille (422) is arranged at the air inlet (421), and the opening ratio of the grille (422) is not less than 50%.

8. The electric heater according to claim 5, wherein The surface emissivity of the first heating surface (21) is not lower than 0.8, the surface emissivity of the second heating surface (22) is not higher than 0.3, and the surface emissivity of the reflecting surface (31) is not higher than 0.

3.

9. The electric heater according to claim 1, characterized in that, Both the air outlet cavity (43) and the wind guiding cavity (41) are arranged in a square shape and are perpendicular to each other.

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