Patent Description:
In the related art, in order to increase a degree of intelligence of an oven, the oven is provided with a camera to realize food material identification in a chamber and cooking degree identification of food during the cooking. However, the camera has a specific requirement for operating environment temperature. When the oven is in operation, a large amount of heat is transferred to the camera at a mounting position thereof through a door body glass. As a result, a higher operating environment temperature would affect performance and service life of the camera. <CIT> discloses an oven door assembly for an embedded oven, wherein the oven door assembly comprises a door body comprising a first door plate and a second door plate, a cooling air duct arranged between the first door plate and the second door plate, an air channel inlet being formed in the bottom of the door body, and an air channel outlet being formed in the top of the door body and a fan being arranged in the cooling air duct. <CIT> discloses an oven comprises a box body, a door body and a camera module. Furthermore, <CIT> discloses an oven body and an oven door, wherein the oven body and the oven door are connected together to form a sealed cooking cavity, an image pickup hole which is communicated with the cooking cavity is arranged on the oven body or the oven door, and the inside of the image pickup hole is provided with a camera. In addition, <CIT> discloses a smart microwave oven having a food material collection function comprising a casing, an infrared temperature sensor, wherein the infrared temperature sensor is mounted at a middle position of a top wall of an accommodating cavity and is used for measuring the surface temperature of food material at the interior of the accommodating cavity.

The present invention relates to a household appliance, wherein said household appliance comprises a chamber, a camera, a door body, and a heat dissipate device. The door body is movably connected to a front part of the chamber. A first air duct is defined in the door body, and the camera is located in the first air duct. The heat dissipation device is mounted in the door body and supplies air into the first air duct to dissipate heat for the door body and the camera.

In the household appliance as described above, air is supplied into the first air duct through the heat dissipation device to dissipate heat for the camera and the door body. Thus, it is possible to effectively cool the camera and the door body, and thus requirements for an operating environment temperature of the camera and temperature requirements of the door body can be satisfied.

In some embodiments, the heat dissipation device is located at a lower part of the door body. The camera is located above the heat dissipation device.

In some embodiments, a first glass plate is disposed on an inner side of the door body. The first glass plate isolates the camera in the first air duct from the air in the chamber when the chamber is closed by the door body.

In some embodiments, a second glass plate is disposed on an outer side of the door body. The first glass plate and the second glass plate are spaced apart from each other on the door body to form the first air duct.

According to the invention, the heat dissipation device comprises a first bracket and a first fan. The first bracket comprises a first air duct member. An air outlet is defined in the first air duct member, and an air outlet grid is disposed at the air outlet. The first fan is mounted on the door body by means of the first bracket.

In some embodiments, the air outlet grid directs an air supply direction of the heat dissipation device towards the camera.

In some embodiments, a plurality of first fans is provided and arranged in parallel along a lower part of the door body.

In some embodiments, the first fan comprises a centrifugal fan.

According to the invention, two first fans are provided. The first air duct member has a first ventilation passage, a second ventilation passage, and a connecting ventilation passage. The connecting ventilation passage is in communication with the first ventilation passage, the second ventilation passage, and the air outlet. One of the two first fans is in communication with the first ventilation passage, and another one of the two first fans is in communication with the second ventilation passage. The first ventilation passage is obliquely communicated with the connecting ventilation passage, and the second ventilation passage is horizontally communicated with the connecting ventilation passage.

In some embodiments, a side wall of the connecting ventilation passage away from the air outlet is formed as a flow guide wall.

In some embodiments, a side wall of the connecting ventilation passage away from the air outlet has a shape recessed towards the air outlet grid.

In some embodiments, the household appliance further comprises a second bracket. The camera is mounted in the first air duct by means of the second bracket. The second bracket has an accommodation space. The camera is located in the accommodation space, and the accommodation space has an opening facing towards the heat dissipation device.

In some embodiments, the second bracket has a light blocking member disposed at a front part of the camera.

In some embodiments, the second bracket has a plurality of exhaust holes arranged upwards at different positions on the second bracket. Each of the plurality of exhaust holes is in communication with the accommodation space.

In some embodiments, a control box is fixed to the front part of the chamber and located above the door body. The household appliance further comprises a second air duct member disposed at a top of the chamber. A second fan is disposed in the second air duct member, and the second air duct member has a second air duct. The second air duct has an inlet in communication with the first air duct and an outlet in communication with a gap between the top of the door body and the control box.

In some embodiments, the control box has a touch screen. An operation of the household appliance is controllable through manipulating the touch screen.

In some embodiments, the household appliance further comprises a deflector corresponding to the outlet of the second air duct. The deflector is mounted at a bottom of the control box.

In some embodiments, the deflector comprises a first deflecting member and a second deflecting member. The first deflecting member and the second deflecting member are spaced apart from each other at the outlet of the second air duct to form an air outlet channel.

In some embodiments, the air outlet channel has a central axis inclined upwards from a horizontal direction by a predetermined angle.

In some embodiments, the household appliance comprises an oven.

Additional aspects and advantages of the present disclosure will be provided at least in part in the following description, or will become apparent at least in part from the following description, or can be learned from practicing of the present disclosure.

The above and/or additional aspects and advantages of the present disclosure will become more apparent and more understandable from the following description of embodiments in conjunction with the accompanying drawings, in which:.

Embodiments of the present invention will be described below in detail, examples of the embodiments are shown in accompanying drawings, and throughout the description, the same or similar reference numerals represent the same or similar components or the components having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and merely used to explain the present invention, rather than being construed as limitation on the present invention.

Referring to <FIG>, an embodiment of the present invention provides a household appliance <NUM>. The household appliance <NUM> comprises a chamber <NUM>, a camera <NUM>, a door body <NUM>, and a heat dissipation device <NUM>. The door body <NUM> is movably connected to a front portion of the chamber <NUM>. A first air duct <NUM> is disposed in the door body <NUM>. The camera <NUM> is located in the first air duct <NUM>. The heat dissipation device <NUM> is mounted on the door body <NUM> and configured to supply air into the first air duct <NUM> to dissipate heat for the door body <NUM> and the camera <NUM>.

In the household appliance <NUM> as described above, the air can be supplied into the first air duct <NUM> through the heat dissipation device <NUM> to dissipate heat for the camera <NUM> and the door body <NUM>, it is thus possible to effectively cool the camera <NUM> and the door body <NUM>. As a result, requirements for an operating environment temperature of the camera <NUM> and temperature requirements of the door body <NUM> can be satisfied.

In some embodiments, for a household appliance <NUM> having an intelligent function, specific state information is required to be obtained by collecting image information of materials (such as food). In one embodiment, the household appliance <NUM> is an oven. When the food is cooked by the oven, the image information of the food may be collected and recognized by the camera <NUM> to determine whether cooking conditions are satisfied for the food. In another embodiment, the household appliance <NUM> is a microwave oven. When the food is cooked by the microwave oven, the image information of the food may be collected and recognized by the camera <NUM> to determine whether the cooking conditions are satisfied for the food. The household appliance <NUM> may also be an electric rice cooker, an induction cooker, a steam cooker, a refrigerator, a dishwasher, or the like, which is not limited herein.

The following embodiments will be described by taking the oven as the household appliance <NUM>.

In some embodiments, the oven may generate a large amount of heat when cooking the food. When the chamber <NUM> is closed by the door body <NUM>, the heat is gradually transferred to the door body <NUM>, which rises a temperature around the camera <NUM>. In one example, the chamber has a maximum operating temperature of <NUM>, and a maximum operating environment temperature acceptable by the camera <NUM> is <NUM>. In this case, an extremely high operating temperature would cause the operating environment temperature of the camera <NUM> to exceed an acceptable range, which would affect operating performance and service life of the camera <NUM>.

In connection with <FIG>, in the embodiment illustrated in <FIG>, the heat dissipation device <NUM> sucks external air into the first air duct <NUM> to allow the air to directly flow to the camera <NUM> along the first air duct <NUM>. Since air for heat dissipation is directly obtained at the camera <NUM>, cold air may also enter the first air duct <NUM> from a lower part of the door body <NUM> to dissipate the heat around the camera <NUM>. As a result, a temperature of the camera <NUM> can be generally kept within a normal operating temperature range. Thus, it is possible to ensure that the camera <NUM> is not affected by a high temperature to avoid degradation of the operating performance and the service life of the camera <NUM>. In one example, the heat dissipation device <NUM> may reduce the operating environment temperature of the camera <NUM> to <NUM>. In addition, in this embodiment, the heat dissipation device <NUM> is mounted inside the door body <NUM> (for example, mounted at a position in the first air duct <NUM> close to a bottom the door body <NUM>). In other embodiments, the heat dissipation device <NUM> may be mounted elsewhere in the door body <NUM>. For example, the heat dissipation device <NUM> is mounted at the bottom of the door body <NUM> to ensure that the heat dissipation device <NUM> can supply the air into the first air duct <NUM>.

Further, the heat dissipation around the camera <NUM> can be accelerated by adjusting a volume of supplied air from the heat dissipation device <NUM>. In this case, the camera <NUM> may be disposed at a position in the door body <NUM> close to the chamber <NUM>. As a result, no protrusion for mounting the camera <NUM> is required to be provided on an outer surface of the door body <NUM> to maintain a large distance between the camera <NUM> and the chamber <NUM>, which may avoid potential risks (for example, the user is injured during the using) as well as aesthetics from being affected. In one embodiment, the door body <NUM> is designed without a handle, which provides a flat appearance for the door body <NUM>.

In addition, in connection with <FIG> again, in the embodiment illustrated in <FIG>, a first glass plate <NUM> is disposed on an inner side of the door body <NUM>. In the case where the chamber <NUM> is closed by the door body <NUM>, the first glass plate <NUM> is capable of isolating the camera <NUM> in the first air duct <NUM> from the air in the chamber <NUM>. The camera <NUM> can collect an image of the food in the chamber <NUM> through the first glass plate <NUM>. In one embodiment, the first glass plate <NUM> is a heat insulation glass to decelerate a speed at which the heat in the chamber <NUM> is transferred to the camera <NUM>. Referring again to <FIG>, a second glass plate <NUM> is disposed on an outer side of the door body <NUM>. The first glass plate <NUM> and the second glass plate <NUM> are spaced apart from each other on the door body <NUM> to form the first air duct <NUM>. In this way, a temperature rise of the second glass plate <NUM> can also satisfy safety requirements.

In addition, in other embodiments, the camera <NUM> may be a heat resisting camera <NUM> to improve the maximum operating environment temperature acceptable by the camera <NUM>. A distance formed between the first glass plate <NUM> and the second glass plate <NUM> may be increased to form a large spacing between the camera <NUM> and the chamber <NUM>. Thus, a great volume of the supplied air can be realized. The door body <NUM> may be provided with a plurality of first glass plates <NUM> disposed between the camera <NUM> and the chamber <NUM>.

Referring to <FIG> and <FIG>, in some embodiments, the heat dissipation device <NUM> is located at the lower part of the door body <NUM>, and the camera <NUM> is located above the heat dissipation device <NUM>. In this way, cold air and hot air in the first air duct <NUM> may be easily separated from each other to improve heat dissipation efficiency.

In some embodiments, the camera <NUM> is arranged at an upper part of the door body <NUM>. Thus, the hot air can be easily and quickly discharged out of the first air duct <NUM>. In addition, the heat dissipation device <NUM> is arranged at the lower part of the door body <NUM>. Thus, the heat dissipation device <NUM> can suck the cold air. It can be understood that the hot air gradually flows to a top of the door body <NUM> due to thermal expansion. As a result, it is possible to ensure that the hot air cannot be sucked by the heat dissipation device <NUM> again, which would affect a heat dissipation effect.

Referring to <FIG>, in the embodiments illustrated in <FIG>, a first air outlet <NUM> is defined on the top of the door body <NUM> and in communication with the first air duct <NUM>. As a result, hot air located on the upper part of the door body <NUM> can be discharged out of the first air duct <NUM> along the first air outlet <NUM>. A first air inlet <NUM> is defined on the lower part of the door body <NUM> and in communication with the first air duct <NUM>. As a result, cold air located outside the door body <NUM> can be sucked into the first air duct <NUM> along the first air inlet <NUM>. In the embodiment illustrated in <FIG>, the heat dissipation device <NUM> is disposed close to the first air inlet <NUM>. In this way, cold air near the first air inlet <NUM> can be easily sucked into the heat dissipation device <NUM> by the heat dissipation device <NUM>.

Referring to <FIG> and <FIG>, and according to the invention, the heat dissipation device <NUM> comprises a first fan <NUM> and a first bracket <NUM>. The first fan <NUM> is mounted on the door body <NUM> by means of the first bracket <NUM>. The first bracket <NUM> comprises a first air duct member <NUM>. The first air duct member <NUM> has an air outlet <NUM>. An air outlet grid <NUM> is disposed at the air outlet <NUM>. In this way, airflow for continuous heat dissipation can be provided for the camera <NUM>.

In some embodiments, in the embodiment illustrated in <FIG>, the first fan <NUM> has a first intake <NUM>. An air outlet <NUM> faces upwards and is disposed on the first air duct member <NUM>. The first fan <NUM> can suck the cold air outside the door body <NUM> through the first intake <NUM>, and then deliver the cold air to the air outlet <NUM> along the first air duct member <NUM>. Cold air at the air outlet <NUM> is delivered to the camera <NUM> along the air outlet grid <NUM> to achieve the heat dissipation effect. It can be understood that the cold air outside the door body <NUM> can be continuously sucked by the first fan <NUM>, and thus a continuous heat dissipation can be provided to the camera <NUM>.

Referring to <FIG> and <FIG>, in some embodiments, the air outlet grid <NUM> is configured to direct an air supply direction of the heat dissipation device <NUM> towards the camera <NUM>. In this way, the heat dissipation device <NUM> can directly dissipate heat for the camera <NUM> to improve the heat dissipation efficiency.

In some embodiments, in the embodiment illustrated in <FIG>, when delivered to the air outlet <NUM> by the first fan <NUM>, the cold air flows in a direction defined by the air outlet grid <NUM>, which allows the air supply direction of the heat dissipation device <NUM> to direct towards the camera <NUM>. Thus, it is possible to prevent the cold air from flowing in the door body <NUM> in other directions, which cannot provide directly dissipating heat for the camera <NUM>. Therefore, the heat dissipation efficiency is improved. A number of the air outlet grids <NUM> may be adjusted as desired, or may be selected by testing, which is not limited herein.

Referring to <FIG>, in some embodiments, a plurality of first fans <NUM> is provided and arranged in parallel along the lower part of the door body <NUM>. In this way, when the cold air is sucked by the plurality of first fans <NUM>, heat dissipation amounts for the camera <NUM> and the door body <NUM> can be improved, and a heat dissipation speed is increased.

In some embodiments, the plurality of first fans <NUM> may be or not be uniformly arranged at intervals on the lower part of the door body <NUM>. The plurality of first fans <NUM> is in communication with the first air duct member <NUM> to allow the plurality of first fans <NUM> to simultaneously dissipate heat for the camera <NUM>. In the illustrated embodiment, each of the plurality of first fans <NUM> is in communication with the first air duct member <NUM>. It can be understood that a plurality of first air duct members <NUM> may also be provided. In other embodiments, each first air duct member <NUM> may be only in communication with one of the plurality of first fans <NUM>, or may be in communication with at least two of the plurality of first fans <NUM>. The number of the first fans <NUM> may be selected as desired, or calibrated through testing. The plurality of first fans <NUM> may have the same specification and model, or some or all of the plurality of first fans <NUM> may have different specifications and models. In one embodiment, the first fan <NUM> is a centrifugal fan, which is not limited herein. The term "a plurality of" herein may refer to two or more.

Referring to <FIG> and <FIG>, according to the invention, two first fans <NUM> may be provided. The first air duct member <NUM> has a first ventilation passage <NUM>, a second ventilation passage <NUM>, and a connecting ventilation passage <NUM>. The connecting ventilation passage <NUM> is in communication with the first ventilation passage <NUM>, the second ventilation passage <NUM>, and the air outlet <NUM>. One of the two first fans <NUM> is in communication with the first ventilation passage <NUM>, and the other one of the two first fans <NUM> is in communication with the second ventilation passage <NUM>. The first ventilation passage <NUM> is obliquely connected to the connecting ventilation passage <NUM>. The second ventilation passage <NUM> is horizontally connected to the connecting ventilation passage <NUM>. In this way, the cold air may be intensively delivered to the air outlet <NUM>, which can improve the heat dissipation efficiency.

In some embodiments, in the embodiment illustrated in <FIG> and <FIG>, the first fan <NUM> has a first exhaust port <NUM>. By delivering cold air discharged by two first exhaust ports <NUM> respectively located at two sides into the connecting ventilation passage <NUM>, cold air of a large flow rate may flow in the connecting ventilation passage <NUM>. In this case, the cold air may be intensively discharged to the camera <NUM> along the air outlet grid <NUM>. Thus, it is possible to reduce loss during the delivering (for example, resistance during the delivering, and the cold air flowing in other directions), and ensure the heat dissipation efficiency of the camera <NUM>.

In addition, in the embodiment illustrated in <FIG> and <FIG>, the two first fans <NUM> have a same structure (or it can be understood that they have the same specification and model). Further, both the first fans rotate in a counterclockwise direction. In this case, the first ventilation passage <NUM> is obliquely connected to the connecting ventilation passage <NUM>, and the second ventilation passage <NUM> is horizontally connected to the connecting ventilation passage <NUM>. Therefore, both the first exhaust ports <NUM> are defined towards the connecting ventilation passage <NUM> and opposite to each other, and the first air duct member <NUM> may have a shorter length. As a result, the first air duct member <NUM> has a relatively short length, which in turn provides more compact structure for the heat dissipation device <NUM>. Further, the cold air at the air outlet <NUM> can be quickly discharged along the air outlet grid <NUM>. Thus, good heat dissipation efficiency can be provided.

Referring to <FIG>, in some embodiments, a side wall of the connecting ventilation passage <NUM> away from the air outlet <NUM> has a shape recessed towards the air outlet grid <NUM>. In this way, the cold air in the first air duct member <NUM> has a trend of flowing upwards, which further allows the cold air to be quickly discharged and improves delivering efficiency of the cold air.

In some embodiments, in the embodiment illustrated in <FIG>, the side wall of the connecting ventilation passage <NUM> away from the air outlet <NUM> severs as a flow guide wall <NUM>. The flow guide wall <NUM> is located at a bottom of the connecting ventilation passage <NUM> with respect to the air outlet <NUM>, and is recessed into an arc shape in a extending direction of the connecting ventilation passage <NUM>. In this way, flow resistance of the airflow can be reduced. It can be understood that since the flow guide wall <NUM> is recessed, the connecting ventilation passage <NUM> has a smaller cross-sectional area. In a case where the first fan <NUM> discharges the cold air, the cold air discharged out of the first ventilation passage <NUM> and the second ventilation passage <NUM> may flow to the air outlet <NUM> along the flow guide wall <NUM>. As a result, instead of remaining in the connecting ventilation passage <NUM>, the cold air flowing to the connecting ventilation passage <NUM> can be easily discharged along the air outlet <NUM>.

Referring to <FIG> and <FIG>, in some embodiments, the household appliance <NUM> comprises a second bracket <NUM>. The camera <NUM> is mounted in the first air duct <NUM> by means of the second bracket <NUM>. The second bracket <NUM> has an accommodation space <NUM>. The camera <NUM> is located in the accommodation space <NUM>. The accommodation space <NUM> has an opening <NUM> facing towards the heat dissipation device <NUM>. In this way, centralized heat dissipation may be conveniently performed on the camera <NUM>.

In some embodiments, in the embodiment illustrated in <FIG> and <FIG>, in a case where the cold air is delivered to the camera <NUM>, the cold air may be directly introduced into the accommodation space <NUM> along the opening <NUM> and diffuse around the camera <NUM> to dissipate heat for the camera <NUM>. Referring again to <FIG>, the second bracket <NUM> further has a plurality of exhaust holes <NUM> arranged at different positions on the second bracket <NUM> and facing upwards. Each of the plurality of exhaust holes <NUM> is in communication with the accommodation space <NUM>. When formed in the accommodation space <NUM>, the hot air may be discharged upwards through the plurality of exhaust holes <NUM> to ensure that the hot air is not left in the accommodation space <NUM> and can be simultaneously discharged through the plurality of exhaust holes <NUM>. Therefore, it is possible to ensure that the air in the accommodation space <NUM> may flow from bottom to top. It can be understood that one exhaust hole <NUM> may be provided.

In addition, in other embodiments, the second bracket <NUM> is provided with a light blocking member (not shown). The light blocking member is disposed at a front of the camera <NUM> and configured to avoid accidentally capturing of an inverted image generated from the outside of the door body <NUM> when the camera <NUM> collects the image information. Thus, accuracy of the image information can be ensured.

Referring to <FIG>, in some embodiments, a control box <NUM> is fixed on a front part of the chamber <NUM>. The control box <NUM> is located above the door body <NUM>. The household appliance <NUM> comprises a second air duct member <NUM> arranged at the top of the chamber <NUM>. A second fan <NUM> is disposed in the second air duct member <NUM>. The second air duct member <NUM> has a second air duct <NUM>. The second air duct <NUM> has an inlet <NUM> in communication with the first air duct <NUM>, and an outlet <NUM> in communication with a gap <NUM> between the top of the door body <NUM> and the control box <NUM>. In this way, the air in the first air duct <NUM> can be accelerated by the second air duct member <NUM> to flow from bottom to top. As a result, cooling effect can be improved.

In the embodiment illustrated in <FIG>, the second air duct <NUM> comprises an upper air duct <NUM> and a lower air duct <NUM> that are spaced apart from each other. The second air duct member <NUM> comprises a communication space <NUM> for communicating the upper air duct <NUM> with the lower air duct <NUM>. The second fan <NUM> is located in the communication space <NUM>. The lower air duct <NUM> is in communication with the first air outlet <NUM>. The upper air duct <NUM> is in communication with the gap <NUM> between the top of the door body <NUM> and the control box <NUM>.

In some embodiments, the inlet <NUM> faces towards the first air outlet <NUM> and is disposed close to the first air outlet <NUM>. When the chamber <NUM> is closed by the door body <NUM>, the inlet <NUM> of the second air duct <NUM> is communication with the first air duct <NUM>, and the second fan <NUM> continuously sucks the air at the inlet <NUM> to allow the air in the first air duct <NUM> to be discharged through the first air outlet <NUM> and sucked into the lower air duct <NUM>. Hot air in the lower air duct <NUM> is continuously sucked by the second fan <NUM>, then is discharged into the upper air duct <NUM>, and is finally discharged out of the household appliance <NUM> through the gap <NUM> at the outlet <NUM> of the second air duct <NUM>. As a result, the accelerated airflow from bottom to top can be finally formed in the first air duct <NUM>.

In addition, in the embodiment illustrated in <FIG>, the second air duct member <NUM> can effectively reduce a temperature of the household appliance <NUM> and take away heat to allow an environment temperature of other components of the household appliance <NUM> to be at a suitable temperature. Thus, it is possible to improve service life as well as stability and safety of the household appliance <NUM> during its operation.

In addition, in the embodiment illustrated in <FIG>, the control box <NUM> has a touch screen <NUM>. The household appliance <NUM> is controllable through manipulating the touch screen <NUM> by the user, such as parameter setting, mode setting, startup and shutdown. It can be understood that in other embodiments, the control box <NUM> may be provided with a button, a knob, or the like to achieve the same effect, and the description thereof in detail will be omitted herein.

Referring to <FIG>, in some embodiments, the household appliance <NUM> comprises a deflector <NUM> corresponding to the outlet <NUM> of the second air duct <NUM>. The deflector <NUM> is mounted at a bottom of the control box <NUM>. In this way, it is possible to prevent the hot air discharged through the outlet <NUM> from being sucked into the second air duct <NUM> again.

Claim 1:
A household appliance (<NUM>), comprising:
a chamber (<NUM>);
a camera (<NUM>);
a door body (<NUM>) movably connected to a front part of the chamber (<NUM>), a first air duct (<NUM>) being defined in the door body (<NUM>), and the camera (<NUM>) being located in the first air duct (<NUM>); and
a heat dissipation device (<NUM>) mounted in the door body (<NUM>) and supplying air into the first air duct (<NUM>) to dissipate heat for the door body (<NUM>) and the camera (<NUM>), wherein the heat dissipation device (<NUM>) comprises:
a first bracket (<NUM>) comprising a first air duct member (<NUM>), an air outlet (<NUM>) being defined in the first air duct member (<NUM>), an air outlet grid (<NUM>) being disposed at the air outlet (<NUM>); and
a first fan (<NUM>) being mounted on the door body (<NUM>) by means of the first bracket (<NUM>),
characterized in that
two first fans (<NUM>) are provided;
the first air duct member (<NUM>) has a first ventilation passage (<NUM>), a second ventilation passage (<NUM>), and a connecting ventilation passage (<NUM>), the connecting ventilation passage (<NUM>) being in communication with the first ventilation passage (<NUM>), the second ventilation passage (<NUM>), and the air outlet (<NUM>);
one of the two first fans (<NUM>) is in communication with the first ventilation passage (<NUM>), and another one of the two first fans (<NUM>) is in communication with the second ventilation passage (<NUM>); and
the first ventilation passage (<NUM>) is obliquely communicated with the connecting ventilation passage (<NUM>), and the second ventilation passage (<NUM>) is horizontally communicated with the connecting ventilation passage (<NUM>).