Air conditioner indoor unit

Abstract

Provided is an air conditioner indoor unit that suppresses worsening of the power consumption of an air conditioner by properly positioning an electrical component box that is provided in a space that is above a discharge port that is provided in a housing and in front of a heat exchanger that is inside the housing. An air conditioner indoor unit (1) comprises a housing (2), a heat exchanger (7) that is provided inside the housing (2), a blowing fan (8) that is provided inside the housing (2) so as to be surrounded by the heat exchanger (7), and an electrical component box (20) that accommodates a control board (22) and an electronic component (23) and is provided in a space (A) that is above a discharge port (5) that is provided in the housing (2) and in front of the heat exchanger (7) inside the housing (2). The electrical component box (20) is positioned such that a lower end surface (20a) is above a lower end (8a) of the blowing fan (8) and a rear surface (20b) is inclined 20°–30° forward with respect to a plane (S) that extends along the up-down direction and the left-right direction of the housing (2).

Description

Air conditioner indoor unit

[0001] The present invention relates to an indoor unit of an air conditioner.

[0002] Conventionally, in indoor units of air conditioners, an electrical equipment box containing a control board and electronic components has been positioned above the air outlet and in front of the heat exchanger in an effort to reduce the size of the indoor unit (see Patent Document 1). The indoor unit of the air conditioner shown in Patent Document 1 includes a main casing, a heat exchanger positioned within the main casing, a blower fan positioned within the main casing so as to be surrounded by the heat exchanger, and an electrical equipment box positioned above the air outlet provided in the main casing and in front of the heat exchanger within the main casing.

[0003] JP 2010-65893 A

[0004] However, the conventional air conditioner indoor unit disclosed in Patent Document 1 has the following problem. Specifically, in the air conditioner indoor unit disclosed in Patent Document 1, an electrical equipment box is disposed in the space above the air outlet provided in the main casing and in front of the heat exchanger inside the main casing. However, due to the increasing need for more compact air conditioners in recent years, the space above the air outlet and in front of the heat exchanger has also become smaller. Meanwhile, due to the need for higher performance and functionality in air conditioners, the size of the control board and the electrical equipment box that houses the control board and the like tends to increase. This increases the space required for the electrical equipment box, reducing the space available for disposing the heat exchanger located behind the electrical equipment box inside the main casing. As a result, the heat exchanger itself becomes smaller, resulting in reduced air conditioning performance and increased power consumption.

[0005] Therefore, the present invention has been made to solve this conventional problem, and its object is to provide an indoor unit for an air conditioner that can suppress a deterioration in the air conditioner's power consumption by appropriately arranging the electrical equipment box, which is located above the air outlet provided in the housing and in the space in front of the heat exchanger inside the housing.

[0006] In order to achieve the above-mentioned object, one aspect of the present invention provides an indoor unit of an air conditioner comprising a housing having a front plate, an upper plate, a bottom plate, a left side plate, and a right side plate, a heat exchanger arranged within the housing, a blower fan arranged within the housing so as to be surrounded by the heat exchanger, and an electrical equipment box that houses a control board and electronic components and is arranged in a space above an air outlet provided in the housing and in front of the heat exchanger within the housing, wherein the electrical equipment box is arranged so that its bottom surface is higher than the bottom end of the blower fan and its rear surface is tilted forward by 20 to 30 degrees relative to a plane extending along the vertical and horizontal directions of the housing.

[0007] According to the indoor unit of the air conditioner of the present invention, by appropriately arranging the electrical equipment box located above the air outlet provided in the housing and in the space in front of the heat exchanger inside the housing, it is possible to provide an indoor unit of the air conditioner that can suppress a deterioration in the power consumption of the air conditioner.

[0008] 1 is a front view of an indoor unit of an air conditioner according to an embodiment of the present invention. FIG. 1 is a perspective view of the indoor unit shown in FIG. 1, seen obliquely from above on the right. FIG. 1 is a perspective view of the indoor unit shown in FIG. 1, seen obliquely from below on the left. FIG. 1 is a cross-sectional view taken along line O-O in FIG. 1. FIG. 4 is a cross-sectional view showing in detail the mounting state of the electrical component box in FIG. 4. FIG. 1 is a front view of the indoor unit shown in FIG. 1 with the front grill and housing removed. FIG. 6 is a right side view of FIG. 6. FIG. 7 is a front view of the electrical component box. FIG. 8 is an exploded perspective view of the electrical component box. FIG. 9 is a cross-sectional view of the electrical component box taken along line P-P in FIG.

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiments shown below are examples of devices and methods for embodying the technical concept of the present invention, and the technical concept of the present invention is not limited to the materials, shapes, structures, arrangements, etc. of the components in the embodiments described below. Furthermore, the drawings are schematic. Therefore, it should be noted that the relationships and ratios between thicknesses and planar dimensions differ from the actual ones, and the drawings also include portions where the relationships and ratios of dimensions differ from one another.

[0010] 1 to 4, an indoor unit 1 of an air conditioner includes a housing 2. The housing 2 includes a front plate 2a extending longitudinally in the left-right direction, an upper plate 2b extending rearward from the upper end of the front plate 2a, a bottom plate 2c extending rearward from the lower end of the front plate 2a, a left plate 2d extending rearward from the left ends of the front plate 2a and the bottom plate 2c, and a right plate 2e extending rearward from the right ends of the front plate 2a and the bottom plate 2c. A front grill 3 is attached to the front plate 2a of the housing 2, and a base 6 is provided on the rear side of the housing 2.

[0011] 2, a plurality of intake ports 4 are formed on the top plate 2b of the housing 2. As shown in FIG. 3, a blower port 5 extending in the left-right direction is formed on the bottom plate 2c of the housing 2. The blower port 5 is provided with an upper and lower air direction flap 30 that closes when the unit is not operating and opens when the unit is operating. The housing 2 also contains a heat exchanger 7, a blower fan 8, a drain pan 9, a fan motor 11, a terminal block assembly 12, and an electrical component box 20.

[0012] 4, the heat exchanger 7 is configured by connecting a front-side lower heat exchanger 7a, a front-side upper heat exchanger 7b, a rear-side upper heat exchanger 7c, and a rear-side lower heat exchanger 7d in an inverted V shape in side view. The front-side lower heat exchanger 7a, the front-side upper heat exchanger 7b, the rear-side upper heat exchanger 7c, and the rear-side lower heat exchanger 7d each extend in the left-right direction.

[0013] The blower fan 8 is a cross-claw fan formed in a substantially cylindrical shape that extends longitudinally along the left-right direction of the housing 2 and is surrounded by the heat exchanger 7 from the front and rear. As shown in Figure 7, the fan motor 11 is located at the right end of the blower fan 8 and drives the blower fan 8. A fan cable W1, which serves as wiring that is connected to a control board 22 (described later) inside the electrical component box 20, is connected to the fan motor 11. The drain pan 9 is located below the heat exchanger 7 and receives condensation dripping from the heat exchanger 7 and discharges it to the outside.

[0014] 7, the terminal block assembly 12 is attached to the drain pan cover 10 and disposed below the fan motor 11, and a terminal block (not shown) connected to a power source (not shown) is provided inside the terminal block. An AC cable W2 is connected to the terminal block as wiring connected to a control board 22 (described later) of the electrical component box 20.

[0015] 4 and 5, the electrical component box 20 houses the control board 22 and a plurality of electronic components 23 mounted on the control board 22, and is attached to the tip 9a of the drain pan 9 in the space A above the air outlet 5 formed in the bottom plate 2c of the housing 2 and in front of the heat exchanger 7 within the housing 2. The electrical component box 20 is also positioned close to the right end of the housing 2, as shown in FIG.

[0016] In the indoor unit 1 of the air conditioner configured as described above, when the blower fan 8 is driven by the fan motor 11 and rotates, indoor air is drawn into the indoor unit 1 from the air inlet 4 via a filter (not shown). The air drawn into the indoor unit 1 then exchanges heat with the refrigerant in the heat exchanger 7, becoming cold air and warm air, and this cold air and warm air are then blown out into the room through the air outlet 5.

[0017] Next, the detailed configuration of the electrical component box 20 will be described with reference to FIGS. 8 to 10. FIG. 8 is a front view of the electrical component box, FIG. 9 is an exploded perspective view of the electrical component box, and FIG. 10 is a cross-sectional view of the electrical component box taken along line P-P in FIG. 8. As shown in FIGS. 8 to 10, the electrical component box 20 includes a box body 21 and a lid 24. The box body 21 includes a substantially rectangular bottom plate portion 21a that extends elongatedly in the left-right direction (the left-right direction in FIG. 8), a front plate portion 21b that rises from the front edge (the left edge in FIG. 10) of the bottom plate portion 21a, a rear plate portion 21c that rises from the rear edge of the bottom plate portion 21a, a left side plate portion 21d that rises from the left edge of the bottom plate portion 21a, and a right side plate portion 21e that rises from the right edge of the bottom plate portion 21a, and is open at the top (the upper side in FIG. 8). The right side plate 21e is formed with a fan cable hole 21f through which the fan cable W1 is inserted and an AC cable hole 21g through which the AC cable W2 is inserted. The box 21 also contains a substantially rectangular control board 22 on which a plurality of electronic components 23 are mounted.

[0018] The lid 24 covers the upper side of the box 21 and includes a front inclined plate portion 24a that slopes upward from the front side (the left side in FIG. 10 ) toward the rear side, and a rear inclined plate portion 24b that slopes downward from the upper end of the front inclined plate portion 24a toward the rear side, as shown in FIG. 10 . The housing 24 also includes a rear plate portion 24c that slopes vertically downward from the rear end of the rear inclined plate portion 24b, a left side plate portion 24d that closes the left ends of the front inclined plate portion 24a, the rear inclined plate portion 24b, and the rear inclined plate portion 24c, and a right side plate portion 24e that closes the right ends of the front inclined plate portion 24a, the rear inclined plate portion 24b, and the rear inclined plate portion 24c. As shown in FIG. 10 , the cross-sectional shape of the lid 24 taken along the cutting line P-P shows a portion that covers the upper side of the box 21, i.e., a triangular roof whose two sides are formed by the front inclined plate portion 24a and the rear inclined plate portion 24b. As shown in FIG. 10 , the lid 24 covers the upper side of the box 21 accommodating the control board 22 and the plurality of electronic components 23 , thereby forming the electrical component box 20 .

[0019] As described above, the electrical component box 20 configured as described above is disposed in the space A above the air outlet 5 formed in the bottom plate portion 2c of the housing 2 and in front of the heat exchanger 7 within the housing 2. Here, due to the increasing need for more compact air conditioners in recent years, the space (space A) above the air outlet 5 and in front of the heat exchanger 7 also tends to become smaller. Meanwhile, due to the need for higher performance air conditioners, the size of the control board 22 and electronic components 23 tends to increase, and the size of the electrical component box 20 that houses the control board 22 and electronic components 23 also tends to increase. As a result, a large space (space A) is required to place the electrical component box 20, and the space for placing the heat exchanger 7 located behind the electrical component box 20 within the housing 2 (the dimension H in the front-to-rear direction of the heat exchanger 7 in FIG. 4 ) becomes smaller. As a result, the heat exchanger 7 itself becomes smaller, its heat exchange capacity decreases, and the power consumption of the air conditioner increases. Therefore, some ingenuity is required when arranging the electrical equipment box 20 in the space A above the air outlet 5 and in front of the heat exchanger 7 inside the housing 2 .

[0020] In this embodiment, as shown in Fig. 4, the electrical component box 20 is disposed in the space A so that the bottom surface 20a is located above the bottom end 8a of the blower fan 8, specifically, so that the bottom surface 20a of the electrical component box 20 is located δ above the bottom end 8a of the blower fan 8. Furthermore, as shown in Figs. 4 and 5, the electrical component box 20 is disposed so that the rear surface 20b is inclined forward at an inclination angle θ of 20° to 30° with respect to a plane S extending in the up-down and left-right directions of the housing 2. Here, in the electrical equipment box 20 shown in Figures 8 to 10, the lower side of the electrical equipment box 20 is positioned rearward, the bottom surface 21h of the bottom plate portion 21a of the box body 21 is positioned as the rear surface 20b of the electrical equipment box 20, and the rear surface 20b is tilted forward at an inclination angle θ with respect to a plane S extending along the vertical and horizontal directions of the housing 2, and the front surface 24f of the front inclined plate portion 24a is positioned as the lower end surface 20a of the electrical equipment box 20.

[0021] The reason why the lower end surface 20a of the electrical component box 20 is positioned higher than the lower end 8a of the blower fan 8 is as follows: To improve air conditioning performance, it is necessary to increase the size of the heat exchanger 7, and therefore the rear-side lower heat exchanger 7d is added below the rear-side upper heat exchanger 7c. Furthermore, with the addition of the rear-side lower heat exchanger 7d, it is necessary to position the air outlet 5 slightly higher and direct the airflow in a more horizontal, front-to-rear direction so that the air passes through the rear-side lower heat exchanger 7d. In this case, since the stabilizer (not shown) that forms the air outlet 5 is positioned slightly higher, the electrical component box 20 is positioned in the limited space (space A) in front of the front-side lower heat exchanger 7a. Therefore, the lower end surface 20a of the electrical component box 20 is also positioned higher, and the lower end surface 20a of the electrical component box 20 is positioned higher than the lower end 8a of the blower fan 8.

[0022] The reason why the electrical component box 20 is disposed with its rear surface 20b tilted forward at an inclination angle θ of 20° to 30° with respect to a plane S extending along the up-down and left-right directions of the housing 2 is as follows: If the electrical component box 20 is disposed in the space A with its rear surface 20b tilted forward at an inclination angle θ of 0° with respect to the plane S (with the rear surface 20b parallel to the plane S) while maintaining the dimension L of the housing 2 in the front-to-rear direction, the height of the electrical component box 20 (the height from the bottom surface 21h of the bottom plate portion 21a to the intersection of the front inclined plate portion 24a and the rear inclined plate portion 24b in FIG. 10 ) reduces the space available for disposing the heat exchanger 7 located behind the electrical component box 20. As a result, the size of the heat exchanger 7 is reduced, the heat exchange capacity of the heat exchanger is reduced, and the power consumption of the air conditioner is increased. In fact, as a result of investigation by the present inventors, when the tilt angle θ=0°, the power consumption increased by about 5% compared to when the tilt angle θ=25°.

[0023] Furthermore, even if the electrical component box 20 is placed in the space A with the rear surface 20b of the electrical component box 20 tilted forward at an inclination angle θ = 60° with respect to the plane S while maintaining the dimension L in the front-to-rear direction of the housing 2, the space for placing the heat exchanger 7 located behind the electrical component box 20 is also reduced. As a result, the size of the heat exchanger 7 is reduced, the heat exchange stress of the heat exchanger is reduced, and the power consumption of the air conditioner is increased. In fact, as a result of investigations by the present inventors, when the inclination angle θ = 60°, the power consumption is increased by about 5% compared to when the inclination angle θ = 25°.

[0024] Furthermore, if the electrical component box 20 is placed in the space A with the rear surface 20b of the electrical component box 20 tilted forward at an inclination angle θ = 90° with respect to the plane S while maintaining the dimension L in the front-to-rear direction of the housing 2, the length of the rear surface 20b of the electrical component box 20 reduces the space available for placing the heat exchanger 7 located behind the electrical component box 20. As a result, the size of the heat exchanger 7 is reduced, the heat exchange capacity of the heat exchanger is reduced, and the power consumption of the air conditioner is increased. In fact, as a result of an investigation by the present inventors, when the inclination angle θ = 90°, power consumption is increased by approximately 10% compared to when the inclination angle θ = 25°.

[0025] On the other hand, if the electrical component box 20 is placed in the space A with the rear surface 20b of the electrical component box 20 tilted forward at an inclination angle θ of 20° to 30° with respect to the plane S while maintaining the dimension L in the front-to-rear direction of the housing 2, the space for arranging the heat exchanger 7 located behind the electrical component box 20 does not become smaller. As a result, the size of the heat exchanger 7 is also large, the heat exchange capacity of the heat exchanger does not decrease, and the power consumption of the air conditioner does not increase. In fact, as a result of investigations by the inventors, when the inclination angle θ is 20° to 30°, the increase in power consumption is about 0% to 1%, with the increase being 0% when the inclination angle θ is 25°.

[0026] As a result, the electrical component box 20 is arranged with its rear surface 20b tilted forward at an inclination angle θ of 20° to 30° with respect to a plane S extending in the up-down and left-right directions of the housing 2. In consideration of an increase in power consumption, it is preferable to arrange the electrical component box 20 with its rear surface 20b tilted forward at an inclination angle θ of 24° to 26° with respect to the plane S, and it is more preferable to arrange the electrical component box 20 with its rear surface 20b tilted forward at an inclination angle θ of 25°.

[0027] As shown in FIG. 4 , when the dimension of the housing 2 in the front-to-rear direction is L and the dimension of the heat exchanger 7 in the front-to-rear direction is H, the relationship between L and H is preferably H / L is 0.7 or greater. In fact, in this embodiment, H / L is 0.78. By setting H / L to 0.7 or greater, the size of the heat exchanger 7 can be increased, preventing a decrease in air conditioning performance and suppressing an increase in power consumption. While there is no particular upper limit for H / L, it is preferable to set it to 0.87, taking into account the installation space for the electrical component box 20.

[0028] As shown in FIG. 4 , when the outer diameter of the blower fan 8 is F and the dimension of the housing 2 in the front-to-rear direction is L, the relationship between F and L is preferably F / L is 0.38 or greater. In fact, in this embodiment, F / L is 0.39. By setting F / L to 0.38 or greater, the outer diameter F of the blower fan 8 can be increased to increase the blowing capacity and prevent a decrease in air conditioning performance. Note that there is no particular upper limit for F / L, but since placing the heat exchanger 7 and the blower fan 8 too close to each other can cause noise, taking into account the clearance between them, it is desirable to set the upper limit to 0.52.

[0029] The electrical component box 20 includes a box body 21 that is open at the top and a lid body 24 that covers the top of the box body 21, and the lid body 24 has a triangular cross section when cut along the vertical direction. The electrical component box 20 is disposed with the lower side of the box body 21 facing rearward and the bottom surface 21h of the box body 21 serving as the rear surface 20b. As a result, as shown in FIG. 5 , when the electrical component box 20 is disposed in the space A, the triangular rear inclined plate portion 24b of the lid body 24 fits along the front plate portion 2a of the housing 2, allowing the electrical component box 20 to be appropriately disposed within the limited space A.

[0030] Furthermore, among the multiple electronic components 23 housed inside the electrical component box 20, a specific electronic component 23, for example, an electrolytic capacitor, has a height of 20 mm or more, is mounted on the control board 22, and is arranged vertically from the rear surface 20b (bottom surface 21h). If a tall component having a height of 20 mm or more is mounted on the control board 22 and arranged vertically from the rear surface 20b (bottom surface 21h), the height of the electrical component box 20 (the height from the rear surface 20b (bottom surface 21h) to the intersection of the front inclined plate portion 24a and the rear inclined plate portion 24b in FIG. 5) becomes large, making it difficult to arrange the electrical component box 20 within the limited space A. However, in the case of this embodiment, as shown in Figure 5, the electrical equipment box 20 is positioned with the rear surface 20b tilted forward at an inclination angle θ of 20° to 30° with respect to a plane S extending in the vertical and horizontal directions of the housing 2. Therefore, even if the height dimension of the electrical equipment box 20 is increased, the electrical equipment box 20 can be positioned within the limited space A without any problems.

[0031] Although the present invention has been described above with reference to an embodiment, the present invention is not limited to this and various modifications and improvements can be made. For example, the heat exchanger 7 is not limited to a configuration in which the front-side lower heat exchanger 7a, the front-side upper heat exchanger 7b, the rear-side upper heat exchanger 7c, and the rear-side lower heat exchanger 7d are connected to form an inverted V shape in side view.

[0032] 1 Indoor unit of air conditioner 2 Housing 2a Front plate portion 2b Upper plate portion 2c Bottom plate portion 2d Left side plate portion 2e Right side plate portion 3 Front grille 4 Suction port 5 Outlet 6 Base portion 7 Heat exchanger 7a Front side lower heat exchanger 7b Front side upper heat exchanger 7c Rear side upper heat exchanger 7d Rear side lower heat exchanger 8 Blower fan 9 Drain pan 10 Drain pan cover 11 Fan motor 12 Terminal block assembly 20 Electrical component box 20a Lower end face 20b Rear face 21 Box body 21a Bottom plate portion 21b Front plate portion 21c Rear plate portion 21d Left side plate portion 21e Right side plate portion 21f Hole for fan cable 21g Hole for AC cable 21h Bottom surface of bottom plate portion 22 Control board 23 Electronic components 24 Cover 24a Front inclined plate portion 24b Rear inclined plate portion 24c Rear plate portion 24d Left side plate portion 24e Right side plate portion 24f Front face of front inclined plate portion 30 Vertical and horizontal air direction plate A Space S Plane W1 Fan cable W2 AC cable

Claims

1. An indoor unit for an air conditioner comprising a housing having a front plate, a top plate, a bottom plate, a left side plate, and a right side plate, a heat exchanger arranged within the housing, a blower fan arranged within the housing so as to be surrounded by the heat exchanger, and an electrical equipment box that houses a control board and electronic components and is arranged in a space above an air outlet provided in the housing and in front of the heat exchanger within the housing, wherein the bottom surface of the electrical equipment box is positioned above the bottom end of the blower fan and the rear surface is tilted forward by 20 to 30 degrees with respect to a plane extending along the vertical and horizontal directions of the housing.

2. An indoor unit for an air conditioner as described in claim 1, characterized in that when the front-to-rear dimension of the housing is L and the front-to-rear dimension of the heat exchanger is H, H / L is 0.7 or more.

3. The indoor unit of an air conditioner according to claim 2, wherein when the outer diameter of the blower fan is F, F / L is 0.38 or more.

4. The indoor unit of an air conditioner as described in claim 1, characterized in that the rear surface of the electrical equipment box is positioned with an inclination of 24 to 26 degrees forward relative to a plane extending along the vertical and horizontal directions of the housing.

5. The indoor unit of an air conditioner as described in claim 1, characterized in that the electrical equipment box comprises a box body that is open at the top and a lid body that covers the top of the box body, the lid body having a triangular cross section when cut along the vertical direction, and the electrical equipment box is arranged with the bottom side of the box body as the rear side and the bottom surface of the box body as the rear surface.

6. An indoor unit for an air conditioner as described in claim 1, characterized in that the electronic components housed inside the electrical equipment box have a height of 20 mm or more and are arranged vertically from the rear side.

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