JP7351694B2 - Blower and air conditioning equipment - Google Patents

Description

The present invention relates to a blower and an air conditioner including the blower.

BACKGROUND ART Conventionally, a so-called centrifugal fan is known as this type of blower device, which includes a substantially cylindrical fan that sends air in a direction intersecting a rotation axis, and a casing that houses the fan therein. The casing of the blower has an inlet for sucking in air and an outlet for discharging air, and a bell mouth is formed in the inlet. This bell mouth has the role of introducing air into the inside of the fan (for example, Patent Document 1).

In such an air blower, air is sucked in through the intake port of the casing, is blown out from the inside of the fan toward the outside, and then is discharged from the discharge port of the casing. However, some of the air blown out toward the outside of the fan does not flow toward the discharge port of the casing, but flows backwards, passes between the fan and the upper plate of the casing, and flows into the inside of the fan again. This backflow collides with the air (main flow) flowing in from the bell mouth, disrupting the airflow and causing noise. Therefore, the tip of the bell mouth is shaped to be bent toward the inside of the fan, that is, toward the downstream of the air inflow direction, thereby deflecting the direction of the backflow toward the rotation axis of the fan. By deflecting the direction of the backflow, collision between the backflow and the main flow is suppressed, so the backflow smoothly merges into the main flow, reducing noise.

Japanese Patent Application Publication No. 2015-94251

However, in conventional blowers, the bell mouth forcibly changes the flow of the backflow, so if the flow speed of the backflow is high, the backflow may collide with the bellmouth, causing noise. There is sex.

The present invention is intended to solve the above problems, and an object of the present invention is to provide a blower device that can effectively reduce noise, and an air conditioner equipped with the blower device.

The present invention provides a fan that rotates around a rotation axis and sends air in a direction intersecting the rotation axis;
a casing that houses the fan therein and has an intake port that sucks in air and a discharge port that blows out air;
a bell mouth part provided on the upper plate of the casing and forming the intake port,
The intake port is formed on the upstream side of the upper plate of the casing in the air inflow direction, and at a position where the distance from the upper plate of the casing in the rotation axis direction is maximum,
The bell mouth portion is provided upstream of the upper plate of the casing in the air inflow direction,
The intake surface of the fan is provided on the downstream side of the upper plate of the casing in the air inflow direction,
The ratio L1/L2 between the distance L1 from the upper plate of the casing to the intake port and the distance L2 from the upper plate of the casing to the intake surface of the fan in the direction of the rotation axis is 0.8 to 1. 8, which is a blower device.

By configuring as described above, it is possible to suppress the noise generated when the backflow inside the casing collides with the bell mouth, and also to weaken the flow speed of the backflow to smoothly merge with the main flow of the fan. Therefore, noise can be reduced.

It is a sectional view of the air blower of this embodiment. FIG. 2 is a top view of the air blower according to the present embodiment with the upper plate of the casing removed. It is an enlarged view of the vicinity of the bell mouth part. It is a graph showing the relationship between the height of the bell mouth portion and the noise value. FIG. 1 is an external view of a humidifier including an air blower according to the present embodiment. 1 is a cross-sectional view of a humidifier including an air blower according to the present embodiment. 1 is a cross-sectional view of a humidifier including an air blower according to the present embodiment.

Embodiments of the present invention that are considered suitable will be briefly described by showing the effects of the present invention.

The present invention relates to the shape of a bell mouth formed in a casing of an air blower, and the inlet port for sucking air is located on the upstream side in the direction of air inflow, and in the direction of the fan rotation axis from the upper plate of the casing. It was formed at the position where the distance is maximum. In other words, the tip of the bell mouth has a shape that extends from the upper plate of the casing toward the upstream side in the air inflow direction, instead of bending toward the downstream side in the air inflow direction as in the conventional case. A space is formed between the mouse part and the fan. This space weakens the flow velocity of the backflow air that has flowed into the bell mouth portion, allowing it to smoothly merge with the main flow of air flowing into the fan. Further, since the bell mouth part does not forcibly change the flow of the backflow air, it is possible to suppress the noise generated when the backflow air collides with the bellmouth part, and the noise can be reduced.

Further, the bell mouth portion has a horizontal portion made of a plane extending in a direction perpendicular to the rotation axis of the fan, and an intake port is formed at an end of this horizontal portion. As a result, the backflow air that has flowed into the space between the bell mouth part and the fan is rectified in the horizontal direction when it merges with the main flow, so it can be merged with the main flow more smoothly. Noise can be effectively reduced.

Further, the bell mouth portion is provided upstream of the upper plate of the casing in the air inflow direction. As a result, the backflow air generated inside the casing is not obstructed by the bell mouth before reaching the intake port, which suppresses disturbance of the flow of backflow air and makes it more noisy. value can be reduced.

Further, when L1 is the distance from the upper plate of the casing to the intake port, and L2 is the distance from the upper plate of the casing to the intake surface of the fan, L1/L2 is 0.8 to 1.8. In order to weaken the flow velocity of the backflow air, the space into which the backflow air flows needs to have a certain height, but on the other hand, if the height is too large, turbulence of the backflow air will occur within the space, causing new problems. This may cause a lot of noise. Therefore, the distance ratio L1/L2 is set to 0.8 to 1.8 as a height that does not cause air turbulence while weakening the flow velocity. Thereby, noise can be effectively reduced.

Further, the air conditioner includes the blower device according to any one of claims 1 to 4. This results in an air conditioner with low noise levels and excellent quietness.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view of the blower device of this embodiment, and FIG. 2 is a cross-sectional view taken along line AA' in FIG. The blower device 1 includes a fan 10 that rotates around a rotating shaft 21 and sends air in a direction crossing the rotating shaft 21, a drive motor 20 that is connected to the rotating shaft 21 and rotates the fan 10, and a casing 30 that houses the fan 10. , consists of.

The fan 10 of this embodiment is a so-called sirocco fan having a substantially cylindrical shape, and a plurality of blades 11 elongated in the axial direction of the rotating shaft 21 of the drive motor 20 are radially spaced at a predetermined interval with respect to the rotating shaft 21. It is located in One end of these wing pieces 11 (lower end in FIG. 1) is attached to the outer edge portion of the disk 12, and the other end (upper end in FIG. 1) of these wing pieces 11 is attached to an annular support plate 13. . The disc 12 is fixed at the center to a rotating shaft 21 of a drive motor 20, and the fan 10 rotates around the rotating shaft 21 when the drive motor 20 is driven.

The casing 30 includes a bottom plate 31 to which the drive motor 20 is fixed, a peripheral wall plate 32 curved to surround the outer periphery of the fan 10, and an upper plate 33 that faces the bottom plate 31 with the peripheral wall plate 32 in between. , has an intake port 34 that sucks air from outside of the blower device 1, and a discharge port 35 that discharges the sucked air to the outside of the blower device 1. The arrow shown with a dashed line in the figure shows the direction in which the air flows inside the casing 30, and the air sucked in from the intake port 34 crosses the rotating shaft 21 from the inside of the fan 10 to the outside. After being blown out in this direction, it flows along the peripheral wall plate 32 of the casing 30 and is discharged from the outlet 35 .

In addition, in this embodiment, each surface constituting the casing 30 is described with the intake port 34 facing upward based on FIG. 1, but the blower device 1 is not necessarily used in the state shown in FIG. do not have. Therefore, regardless of the direction in which the air blower 1 is installed, the surface on which the air intake port 34 is formed is the top plate 33, the surface facing the top plate 33 is the bottom plate 31, and the surface is arranged between the top plate 33 and the bottom plate 31. The surface becomes the side peripheral wall 32.

A bell mouth portion 36 is integrally formed on the upper plate 33 of the casing 30. The bell mouth portion 36 is formed to protrude further outside the casing 30 than the upper plate 33, in other words, on the upstream side in the air inflow direction, and the inlet port 34 is provided at the end of the bell mouth portion 36. In order to suppress noise during air intake, the diameter of the intake port 34, which is the minimum inner diameter of the bell mouth portion 36, is made larger than the inner diameter of the fan 10 (the inner diameter of the blade 11).

FIG. 3 is an enlarged view of the vicinity of the bell mouth portion. In the following description, the upstream side in the air inflow direction will be referred to as the upper direction, the direction along the rotation axis 21 of the fan 10 will be referred to as the vertical direction, and the direction perpendicular to the rotation axis 21 will be referred to as the horizontal direction.

In FIG. 3, H represents the distance between the intake port 34 formed in the bell mouth portion 36 and the upper plate 33 of the casing 30 in the rotation axis direction of the fan 10 (vertical direction in the figure). The intake port 34 is formed on the upstream side in the air inflow direction at a position where the distance H is maximum. In other words, the tip of the bell mouth portion 36 is bent from the upper plate 33 of the casing 30 upstream in the air inflow direction, instead of being bent toward the inside of the fan 10, that is, toward the downstream side in the air inflow direction as in the conventional case. It has a shape that extends toward the side. As a result, the intake port 34 is provided at a higher position than the upper plate 33 of the casing 30, and a space S is formed between the bell mouth portion 36 and the intake side surface of the fan 10.

The air flowing in through the intake port 34 is blown out from the inside of the fan 10 toward the outside, as described above, and then is discharged from the discharge port 35. However, a part of the air blown out toward the outside of the fan 10 does not flow toward the discharge port 35 but flows backward. This backflowing air is referred to as backflowing air R. The backflow air R passes between the fan 10 and the upper plate 33 of the casing 30, further flows through the space S formed below the bell mouth portion 36, and flows into the inside of the fan 10 again. If the flow velocity of the backflow air R is high, it collides with the main flow when it joins the air flow (hereinafter referred to as the main flow) flowing in from the intake port 34, and furthermore, it causes noise because it causes disturbance in the main flow. However, in this embodiment, since the space S is a relatively wide space, the flow velocity of the backflow air R is weakened when flowing into the space S, suppressing collision with the main flow and smoothly merging into the main flow. can be done. Thereby, the noise value can be reduced. Further, since the bell mouth section 36 does not forcibly change the flow of the backflow air R as in the conventional case, it is effective to prevent the backflow air R from colliding with the bell mouth section 36 and causing noise. Can be suppressed.

Further, the bell mouth portion 36 can have a shape including a step portion 36a extending diagonally upward from the upper plate 33 of the casing 30, and a horizontal portion 36b extending horizontally from the step portion 36a. As a result, when the backflow air R that has flowed into the space S below the bell mouth portion 36 merges with the main flow, the direction of the flow is rectified in the horizontal direction, so that it can be merged with the main flow more smoothly. Noise can be effectively reduced.

Further, the bell mouth portion 36 can be provided above the upper plate 33 of the casing 30. As a result, a wide space S can be secured, and the flow of the backflow air R is not obstructed by the bell mouth portion 36 before reaching the intake port 34, so that the flow of the backflow air R is disturbed. This can further reduce the noise level.

Note that the shape of the bell mouth portion 36 of this embodiment is one example for achieving the above-mentioned effects, and is not limited to this. The bell mouth portion 36 may be formed so as to suppress the collision between the backflow air R and the bellmouth portion 36 and to weaken the flow velocity of the backflow air R. In other words, the bellmouth portion 36 is formed so as to suppress the collision between the backflow air R and the bellmouth portion 36 and to weaken the flow velocity of the backflow air R. , assuming that the distance between the casing 30 and the upper plate 33 in the vertical direction is H, the intake port 34 may be formed on the upstream side in the air inflow direction at a position where the distance H is maximum. Therefore, the stepped portion 36a may extend in the vertical direction or may have an arc shape. Furthermore, it may be a combination of step portions 36a having different shapes. Moreover, the bell mouth part 36 does not need to include only the stepped part 36a and the horizontal part 36b.

By the way, in order to weaken the flow velocity of the backflow air R, the space S needs to have a certain height, but on the other hand, if the height is too large, turbulence will occur in the flow of the backflow air R within the space S. This may cause new noise. Therefore, the bell mouth portion 36 needs to be set at a height that does not cause turbulence while weakening the flow velocity of the backflow air R.

FIG. 4 is a graph showing the relationship between the height of the bell mouth portion and the noise value. The horizontal axis of the graph is the distance between L1 and L2, where L1 is the distance from the upper plate 33 of the casing 30 to the intake port 34, and L2 is the distance from the upper plate 33 of the casing 30 to the intake surface of the fan 10. The ratio (L1/L2), the vertical axis is the noise value. More specifically, the upper plate 33 of the casing 30 that serves as the reference for the distances L1 and L2 refers to the inner wall surface 33a of the upper plate 33. As shown in the graph, the noise value is the lowest when L1/L2 is approximately 1.3. From this, it is possible to more effectively reduce noise by setting upper and lower limits for L1/L2, and it is preferable to set L1/L2 in the range of 0.8 to 1.8. good. Therefore, for example, when L2 is 4.5 mm, the optimal value for the height L1 of the bell mouth portion 36 is 3.6 mm to 8.1 mm.

Next, an example in which the blower of this embodiment is used as a blower in an air conditioner will be described with reference to FIGS. 5 to 7.

FIG. 5 is an external view of a humidifier that is an example of an air conditioner including the blower of this embodiment. Note that the air conditioner is not limited to a humidifier, and may be any device that regulates indoor air, and can also be applied to an air purifier, a heating device, and the like. The humidifying device 50 includes, on the top surface of a main body 51, an operating section 52 that includes various buttons for instructing operations of the humidifying device 50, and an air outlet 53 that blows out humidified air generated inside the device.

FIG. 6 is a sectional view of the humidifying device along the YZ plane, and FIG. 7 is a sectional view of the humidifying device along the XY plane. A water supply tank 54 for supplying water is arranged on the inside side of the main body 51, and at the bottom of the main body 51 there is a water tank section 55 for storing a certain amount of water supplied from the water tank 54; A vaporizing filter 56 is disposed that absorbs water stored in the water tank 55 and moistens it. Furthermore, a suction port 58 for taking in air into the main body 51 is provided on the back surface of the main body 51.

Furthermore, an air blowing section 57 that generates air flow within the main body 51 is provided at the upper part of the vaporization filter 56 . The air blowing unit 57 in the humidifying device 50 of this embodiment is the air blowing device 1 described above attached so that the drive motor 20 is located on the side. Therefore, the intake port 34 of the casing 30 opens to the side, and the discharge port 35 opens upward. The outlet 35 communicates with an outlet 53 of the humidifier 50.

When the fan 10 is rotated by the driving of the drive motor 20, the air that has flowed in from the intake port 34 of the blower section 57 is discharged from the discharge port 35. This air flow blows air into the ventilation path from the suction port 58 on the back surface of the main body 51 to the air outlet 53 on the top surface. Further, upstream of the vaporization filter 56 in the ventilation path, a hot air heater 59 is provided to heat the air introduced from the suction port 58 and turn it into hot air. Therefore, the indoor air taken in from the suction port 58 is heated by the hot air heater 59, becomes humidified air when it passes through the vaporization filter 56 which sucks up the water in the water tank 55, and becomes moist. 53 into the room, the air is humidified.

In such a humidifying device 50 as well, the noise of the air blowing section 57 can be reduced, so that the device is excellent in quietness and can be used comfortably.

1 Blower device 10 Fan 21 Rotating shaft 30 Casing 33 Upper plate 34 Intake port 35 Discharge port 36 Bell mouth portion 36b Horizontal portion

Claims (3)

a fan that rotates around a rotation axis and sends air in a direction intersecting the rotation axis;
a casing that houses the fan therein and has an intake port that sucks in air and a discharge port that blows out air;
a bell mouth part provided on the upper plate of the casing and forming the intake port,
The intake port is formed on the upstream side of the upper plate of the casing in the air inflow direction, and at a position where the distance from the upper plate of the casing in the rotation axis direction is maximum,
The bell mouth portion is provided upstream of the upper plate of the casing in the air inflow direction,
The intake surface of the fan is provided on the downstream side of the upper plate of the casing in the air inflow direction,
The ratio L1/L2 between the distance L1 from the upper plate of the casing to the intake port and the distance L2 from the upper plate of the casing to the intake surface of the fan in the direction of the rotation axis is 0.8 to 1. 8, a blower device. The bell mouth part has a horizontal part made of a plane extending in a direction perpendicular to the rotation axis,
The blower device according to claim 1, wherein the air intake port is formed at an end of the horizontal portion. An air conditioner comprising the air blower according to claim 1 or 2.

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