JPH07127875A - Ceiling embedded type air conditioner - Google Patents

Abstract

PURPOSE:To maintain a pressure difference between an air intake port and an air exhaust port constant and to sufficiently cool a motor with air forcible circulation flow by providing the intake port at an upstream side of a fan rotor and providing the exhaust port at a side opposed position of the rotor. CONSTITUTION:Since a static pressure of an air exhaust port 7 when a fan rotor 3 is rotated is lower than that at an air intake port 6, part of the air flow at an upstream of the rotor 3 is sucked from the port 6 by its pressure difference thereby to generate a forcible circulation flow to the port 7 through a motor 11 in a cooling passage 13, thereby cooling the motor 11 by the circulation flow. In this case, since distributions of the static pressures in openings of the intake port 6 and the exhaust port are relatively constant, a pressure difference between the port 6 and the port 7 is stabilized, and since its pressure difference can satisfy necessary level, the circulation flow generated in the passage 13 can be sufficiently obtained as a necessary amount.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceiling-embedded air conditioner for forcibly cooling a motor that drives a fan rotor of an indoor unit.

[0002]

2. Description of the Related Art An indoor unit in a ceiling-embedded air conditioner is installed behind the ceiling, but the inside ceiling is generally hotter and humid than the room. For this reason, it is difficult to cool the motor that drives the fan rotor of the indoor unit by natural cooling with the air in the ceiling. Therefore, a part of the air flow generated by the rotation of the fan rotor is taken into the motor housing part and the motor is stored. It was done by the method of forced cooling. For example, in FIG. 5 and FIG. 6, the indoor unit of the conventional ceiling-embedded air conditioner is used by inserting the main body 21 into the mounting hole 10 provided in the ceiling 9. In this indoor unit, by driving the fan rotor 23 with the motor 31, the indoor air is sucked from the suction port 24 and blown out toward the heat exchanger 22 as shown by the white arrow in FIG. Then, the air that has exchanged heat with the refrigerant when passing through the heat exchanger 22 is again blown out into the room from the air outlet 25 as shown by the white arrow in FIG. The air outlet 27 is provided upstream of the fan rotor 23 on the side wall 32 to which the motor 31 is attached, while the air is discharged to a portion of high static pressure generated by the rotation of the fan rotor 23 on the downstream side. By providing the intake port 26, a circulating flow of air shown by an arrow in FIG. 6 from the air intake port 26 to the air discharge port 27 via the motor 31 is generated, thereby cooling the motor 31 (for example, See Japanese Patent Laid-Open No. 344029/1992).

[0003]

However, although the static pressure distribution at the air outlet 27 in FIGS. 5 and 6 is relatively constant, the static pressure distribution at the air intake 26 is not constant, and the opening portion thereof is not constant. Since the static pressure fluctuates greatly depending on the location, the pressure difference between the air intake port 26 and the air exhaust port 27 was not stable as a whole.

The present invention has been made to solve the above-mentioned conventional drawbacks, and an object thereof is to obtain a stable pressure difference between an air intake port and an air exhaust port, and therefore to prevent forced circulation of air. An object is to provide a ceiling-embedded air conditioner that can sufficiently cool a motor.

[0005]

Therefore, in the ceiling-embedded air conditioner of the present invention, the fan rotor 3 is housed in the main body 1, and the side surface of the fan rotor 3 faces the outside of the side wall 12 of the main body 1. A motor 11 for driving the fan rotor 3 is mounted, and a cooling passage 13 for communicating the air intake 6 and the air exhaust 7 formed in the side wall 12 with each other.
In the ceiling-embedded air conditioner having a structure in which the motor 11 is arranged, the air intake 6 is provided on the upstream side of the fan rotor 3, and the air discharge port 7 is provided.
Is provided at a position facing the side surface of the fan rotor 3.

[0006]

In the above-mentioned ceiling-embedded air conditioner, the static pressure distribution at the air intake 6 and the static pressure distribution at the air discharge port 7 are relatively constant, and therefore the pressure difference between the two is sufficiently stable, so that it is stable. The forced circulation flow described above is obtained, which enables efficient cooling of the motor 11.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the ceiling-embedded air conditioner of the present invention will be described in detail with reference to the drawings. 1 is a partial cross-sectional view of an embodiment of an indoor unit of a ceiling-embedded air conditioner of the present invention, FIG. 2 is a conceptual diagram showing a cooling passage that connects the air intake port and the air discharge port in FIG. 1, FIG. 3 is a display diagram of static pressure measurement points on the side wall facing the fan rotor of the embodiment, and FIG. 4 is a diagram showing static pressure measurement results at each point in FIG.

1 and 2, in the indoor unit of the ceiling-embedded air conditioner of the present invention, a suction port 4 is provided on one side of the main body 1 facing the room, and an air outlet 5 is provided on the other side. The heat exchanger 2 and the fan rotor 3 are arranged in the main body 1 in this order from the suction port 4 to the air outlet 5. Then, as shown in FIG. 2, a motor 11 for driving the fan rotor 3 is attached to the outside of the side wall 12 of the main body 1 facing the side surface of the fan rotor 3. An air intake 6 is provided on the side wall 12 on the upstream side of the fan rotor 3, and also on the side wall 12,
An air discharge port 7 is provided in a portion near the blower outlet 5 within a range in which the side surface of the fan rotor 3 is projected on the side wall 12 in the axial direction thereof. The motor 11 is housed in the cooling passage 13 that connects the air intake 6 and the air exhaust 7. The indoor unit configured as described above has the mounting hole 1 provided in the ceiling 9.
The main body 1 is inserted into 0 to be installed and used.

In the indoor unit of the ceiling-embedded air conditioner having the above structure, the fan rotor 3 is driven by the motor 11.
When is driven, the air in the room is sucked through the suction port 4 and blown out toward the heat exchanger 2 as shown by the white arrow in FIG. The air that has exchanged heat with the refrigerant when passing through the heat exchanger 2 is blown out into the room again from the air outlet 5 as shown by the white arrow in FIG. 2, thereby realizing the function as an air conditioner. . Here, in FIG. 2, the suction port 4 and the heat exchanger 2
Also, the air outlet 5 is simplified so that the air flow can be easily understood.

In the above structure, the motor 11 is cooled as follows. That is, since the static pressure at the air discharge port 7 when the fan rotor 3 is rotating is lower than the static pressure at the air intake port 6, the difference in pressure causes
A part of the air flow upstream of the fan rotor 3 is taken in from the air intake port 6 and a forced circulation flow (arrow in FIG. 2) is generated to reach the air exhaust port 7 via the motor 11 in the cooling passage 13,
The motor 11 is cooled by this forced circulation flow. At this time, since the static pressure distribution in the openings of the air intake 6 and the air outlet 7 is relatively constant, the pressure difference between the air intake 6 and the air outlet 7 is stable, and the pressure difference is also required. Since the necessary level of the forced circulation flow generated in the cooling passage 13 can be secured in a sufficiently stable manner, the motor 1
1. Efficient cooling can be achieved.

The above is supported by the following experiments.
In this experiment, the air inlet 6 and the air outlet 7 of the indoor unit of the ceiling-embedded air conditioner according to this example were closed, and the various places shown in FIG. 3 on the surface of the side wall 12 facing the fan rotor 3. At this point, the static pressure generated under the influence of the rotation of the fan rotor 3 is measured, and FIG. 4 shows the result. Here, all measured values are differential pressures from atmospheric pressure.

As a result of the above experiment, in FIG.
The static pressure at each point of B and C is -2.7 to -2.8 mmAq and the fluctuation range is 0.1 mmAq, which are relatively constant. The static pressure at each point of D, E, F, and G is -4.2 to -4.5 mm.
Aq and the fluctuation range are 0.3 mmAq, which are also relatively constant.

On the other hand, the static pressure at each point of H, J, K, and L is -2.3 to -5.9 mmAq, and the fluctuation range is 3.6 mmA.
q, and the static pressure at each point of M, N, P is +0.6 to −
The variation range is 0.6 mmAq and the variation range is 1.2 mmAq, both of which are significantly different from the above points, and the static pressure distribution cannot be said to be constant.

From the above, in the present embodiment in which the vicinity of points A, B and C are used as the air inlet and the vicinity of points D, E, F and G are used as the air outlet, a stable static pressure is obtained. Due to the distribution, the air intake port and the air exhaust port can be formed as large openings instead of small holes that make whistling noises, and whistle noises can be avoided. Further, the pressure difference between the intake port and the discharge port is stable, and at the same time, the pressure difference is 1.5
Since mmAq is secured, the forced circulation flow required for cooling the motor can be secured stably.

On the other hand, in the conventional example in which the air inlets are near the points M and N and the air outlets are near the points A, B, and C, the static pressure distribution at the air inlets is stable. Therefore, it is understood that the pressure difference between the air intake port and the air exhaust port is not stable, and the forced circulation flow required for cooling the motor cannot be stably obtained as described above.

According to the results of the above experiment, H
Since the static pressure at each point of ~ L is partially lower than the static pressure at each point of D ~ G, the air discharge port 7 is, for example, J
It may be considered to be near the point. However, the static pressure in the area corresponding to the air exhaust port is not stable as described above, and therefore the pressure difference between the air intake port and the air exhaust port is not stable, so the forced circulation flow necessary for cooling the motor cannot be obtained stably. This structure has the same drawbacks as the conventional example. Further, in the above structure, since the air outlet faces the side surface of the air passage of the fan rotor 3, when the cooling circulation flow of the motor 11 is discharged from the air outlet, the air passage formed by the fan rotor 3 is There is also a drawback that the air flow is disturbed and the air blowing performance of the air conditioner is reduced.

On the other hand, in this embodiment, the air discharge port 7 is provided so as to face the side surface of the fan rotor 3 in FIG. Since the flow of the air conditioner is not disturbed, the ventilation performance of the air conditioner does not deteriorate.

[0018]

As described above, in the ceiling-embedded air conditioner of the present invention, the static pressure distributions at the air intake and the air exhaust for cooling the motor are substantially constant.
The pressure difference between the air intake port and the air exhaust port is also stable, and a stable circulating air flow is obtained, so that the motor can be efficiently cooled. Further, since the air outlet faces the side surface of the fan rotor and therefore does not face the air passage, the flow of the air in the air passage is not disturbed, and it is possible to avoid deterioration of the air blowing performance. Further, since the opening can be made relatively large, it is possible to suppress the generation of whistle noise.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of an example of an indoor unit of a ceiling-embedded air conditioner of the present invention.

FIG. 2 is a conceptual diagram showing a cooling passage that connects an air intake port and an air exhaust port in FIG.

FIG. 3 is a display diagram of static pressure measurement points on a side wall facing the fan rotor of the embodiment.

FIG. 4 is a diagram showing the result of static pressure measurement at each point in FIG.

FIG. 5 is a partial cross-sectional view of an indoor unit of a ceiling-embedded air conditioner in a conventional example.

FIG. 6 is a conceptual diagram showing a cooling passage that connects an air intake port and an air exhaust port in FIG.

[Explanation of symbols]

 1 Main Body 3 Fan Rotor 6 Air Inlet 7 Air Outlet 11 Motor 12 Sidewall 13 Cooling Passage

Claims (1)

[Claims] 1. A fan rotor (3) is housed in a main body (1), and the fan rotor (3) is provided outside a side wall (12) of the main body (1) facing a side surface of the fan rotor (3). A motor (11) for driving is attached, and the motor (11) is provided in a cooling passage (13) that communicates an air intake (6) and an air outlet (7) formed in the side wall (12). In the ceiling-embedded air conditioner having a structure in which the air intake (6) is provided upstream of the fan rotor (3), and the air discharge port (7) is the fan rotor. (3) A ceiling-embedded air conditioner, which is provided at a side-to-side facing position.