JPH086707B2 - Once-through blower - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a cross-flow fan provided in, for example, an indoor unit of an air conditioner.

[Conventional technology]

FIG. 5 is a sectional view of an indoor unit of an air conditioner incorporating a conventional once-through fan as disclosed in Japanese Utility Model Laid-Open No. 62-36277, for example, in which (1) is a rear guider,
(2) is a guide wall, and (3) is a stabilizer. The casing formed by these is provided with a blow-out nozzle (4) on the lower side of the front face, and a suction port (5) is provided above it to face it. The heat exchanger (6) is arranged, and the impeller (7) is installed behind the heat exchanger (6).

Next, the operation will be described. The guide wall (2) and the stabilizer (3) forming the impeller (7) and the casing allow the air sucked from the suction port (5) to exchange heat when passing through the heat exchanger (6). As a result, cold air or warm air is blown, and the air is blown into the room from the blowing nozzle (4). At this time, the stabilizer (3) restrains and fixes the dominant vortex (8) generated in the impeller (7) together with the guide wall (2), stabilizes the cross flow (9), and creates a blown state.

[Problems to be Solved by the Invention]

However, once-through blowers are less efficient than other blowers, and the problem of noise countermeasures often comes into play as efficiency increases. That is, as shown in FIG. 6, the back surface of the stabilizer (1) flows between the stabilizer (3) and the impeller (7).
The dead water region (11) is made large and long until the confluence of the (0) and the governing vortex (8), and the impeller (7) is dead depending on the distance between the stabilizer (3) and the impeller (7). Body of water (11)
A noise called blade pitch noise is generated at the frequency of the product of the number of blades and the rotation speed of the impeller (7) and its multiple.

If the stabilizer (3) is extended as it is to increase the efficiency, the dominant vortex (8) is disturbed, the throughflow (9) becomes unstable, and noise increases. FIG. 2 shows a graph of the noise measured at this time.

It is also possible to increase the distance between the stabilizer (3) and the impeller (7) so that the impeller (7) does not cross the dead water area (11), but this reduces efficiency and makes the flow unstable. There was a problem.

The present invention has been made to solve the above problems, and while maintaining efficiency, suppresses noise at a specific frequency with a periodicity called the blade pitch noise as described above, and It is intended to provide a stable once-through blower.

[Means for solving the problem]

A cross-flow fan according to the present invention is a cross-flow fan including an impeller and a casing that incorporates the impeller and forms a discharge passage that guides a flow of a fluid discharged from the impeller. And a suction flow guide that is provided at the tip of the stabilizer and that is formed in an arc shape along the impeller,
The suction flow guide is formed so that the wall thickness of the suction flow guide becomes thinner toward the tip of the suction side. Further, a stabilizer protrusion is provided between the stabilizer and the suction flow guide, and extends a shortest distance portion between the impeller and the stabilizer.

[Action]

The once-through blower configured as described above is provided with a suction flow guide formed in an arc shape along the impeller at the tip of the stabilizer, and the thickness of the suction flow guide provided is the suction side tip. Since it is formed so that it becomes thinner as it goes to, the collision between the vortex flow near the tip of the stabilizer and the blade of the impeller is reduced, and the fluid between the back side and the front side that flows to the guide through the stabilizer is reduced. The dead water area formed by the flow of water is reduced.

Further, the stabilizer protrusion is provided between the stabilizer and the suction flow guide, and extends the shortest distance portion between the impeller and the stabilizer, thereby improving the blowing efficiency.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, (3) is a stabilizer, and (12) is a stabilizer protrusion attached to the fan facing surface side of the stabilizer (3), which is a point at which the distance between the stabilizer and the impeller is minimized. Similarly, (13) is a suction flow guide bent from the tip of the stabilizer (3) in the direction of the impeller in an arc shape, and is made thinner than the thickness of other parts of the stabilizer (3), and as it goes to the tip. It is thinning.

FIG. 4 shows the flow state of the once-through blower according to the present invention. Since there is a suction flow guide (13) at the tip of the stabilizer (3), the stabilizer back flow (10) and the dominant vortex flow (8) flow along this guide and are separated from the stabilizer part. After that, they merge immediately and the generation of the dead water area (11) is suppressed, and by this, the blade pitching sound generated due to the impeller (7) crossing this dead water area (11) is suppressed. Furthermore, by making this suction flow guide (13) arcuate in the direction of the impeller, the energy loss due to the collision between the vortex flow near the stabilizer and the blade of the impeller is reduced,
The flow is stabilized and the increase in the impeller speed due to the lengthening of the stabilizer can be suppressed. Moreover, since the generation of the dead water area (11) is suppressed, the shortest distance between the stabilizer (3) and the impeller (7) can be further shortened, and the vorticity of the dominant vortex (8) increases, The flow becomes more stable.

〔The invention's effect〕

Since the present invention is configured as described above, it has the effects described below. A suction flow guide formed in an arc shape along the impeller is provided at the tip end of the stabilizer, and the wall thickness of the suction flow guide provided is formed so as to become thinner toward the tip on the suction side. Therefore, the collision between the vortex flow near the tip of the stabilizer and the blade of the impeller is reduced, and the dead water area formed by the flow of the fluid on the back side and the surface side flowing to the guide through the stabilizer is reduced. In order to reduce the size, the flow of the fluid is stabilized, the impeller does not cross the dead water region, and a quiet flow-through blower that suppresses the generation of a noticeable blade pitch sound is obtained.

Further, the stabilizer protrusion is provided between the stabilizer and the suction flow guide, and extends the shortest distance portion between the impeller and the stabilizer, so that the ventilation efficiency is improved, and thus a cross-flow fan with good ventilation performance is provided. can get.

[Brief description of drawings]

FIG. 1 is a sectional view of an indoor unit of an air conditioner incorporating the once-through blower of the present invention, FIG. 2 is a noise measurement graph including blade pitch noise, and FIG. 3 is an exploded view of the indoor unit incorporating the present invention, FIG. 4 is a state diagram of the stabilizer and the dead water area near the impeller according to the present invention, FIG. 5 is a partial sectional view of an indoor unit of an air conditioner incorporating a conventional once-through fan, and FIG. 6 is a conventional stabilizer. It is a state diagram of the dead water area near the impeller. In the figure, (3) is a stabilizer, (7) is an impeller, and (8).
Is the dominant vortex, (10) is the back flow of the stabilizer, (11) is the dead water area, (12) is the protrusion of the stabilizer, and (13) is the suction flow guide. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (2)

[Claims] 1. A cross-flow fan comprising an impeller and a casing that incorporates the impeller and forms a discharge passage for guiding the flow of fluid discharged from the impeller, forming a part of the casing. A stabilizer and a suction flow guide which is provided at the tip of the stabilizer and is formed in an arc shape along the impeller are provided, and the thickness of the suction flow guide becomes thinner toward the suction side tip. A cross-flow blower, which is characterized by being formed as follows. 2. A stabilizer protrusion is provided between the stabilizer and the suction flow guide, and extends a shortest distance portion between the impeller and the stabilizer. The once-through blower according to 1.