JP2658639B2 - Cross flow fan for hot air heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in air blowing performance when a cross flow fan is used as a convection fan for indoor circulation of a hot air heater.

[0002]

2. Description of the Related Art Conventionally, the structure of this type of heater is as follows.
It is disclosed in Japanese Utility Model Laid-Open No. 57-16721.
FIG. 3 shows the embodiment. An air duct 2 is formed in a main body 1, and a combustion device 3 and a convection cross flow fan 5 are disposed in the air duct 2. The above combustion device 3
Is composed of a chamber 13 for accommodating a burner section, a combustion tube 14 through which high-temperature combustion gas passes, and a heat exchanger 4 through which relatively low-temperature gas passes. On the other hand, outside the air duct 2, a combustion blower 6 for supplying air required for combustion to the burner and a motor 7 for driving the cross flow fan 5 are provided. Further, a filter 10 is provided at the suction port 9 of the cross flow fan 5 to remove dust and prevent the dust from entering the ventilation path 8.

Next, the operation will be described. The high-temperature gas burned in the burner passes through the heat exchanger 4 from the combustion tube 14 and is discharged outside the room. Next, when the cross flow fan 5 operates, the room air flows from the suction port 9 through the filter 10 into the ventilation passage 8 through the inside of the cross flow fan 5, and the heat exchange between the combustion tube 14 and the heat exchanger 4. Then, the air becomes high-temperature air and is discharged out of the machine from a blowing grill (not shown).

[0004] Since the hot air heater is generally installed on the floor in a room, a large amount of dust adheres to the filter 10, thereby increasing the resistance of the air passage generated by the cross flow fan 5. However, the cross flow fan 5 has a drawback that the so-called surging phenomenon in which the flow in the cross flow fan 5 fluctuates greatly with a relatively small pressure loss due to a small resistance to the air path resistance, that is, the pressure loss, is apt to occur. I have. Therefore, since it cannot be used as a convection fan of a warm air heater, the device for improving the surging resistance has been devised.

As one example for improving the surging resistance, there is a conventional example disclosed in Japanese Utility Model Laid-Open No. 1-125890.
FIG. 4 shows the structure. That is, the rectifying plates 1-2 are provided at both ends of the outlet of the cross flow fan. The surging phenomenon originates from the disruption of the flow on both end faces of the cross flow fan, which spreads to the entire fan, so that the wind does not flow from both ends of the cross flow fan outlet from the beginning. It is.

[0006]

A conventional cross-flow fan for a warm air heater is constructed as described above, and is provided with a rectifying plate on a blowing surface to improve surging resistance. Some flow will also exist at both ends of the surface, and the surging resistance cannot be greatly improved.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a conventional cross-flow fan for a warm air heater with improved surging resistance.

[0008]

In order to achieve the above object, a cross flow fan according to the present invention has a cover formed on a casing to cover the peripheral surfaces of both ends of an impeller, and has an L-shaped cross section. The short side of the current plate is held at a predetermined interval on the cover body.
With the long side parallel to the inside of the casing with a space between them and looking in the longitudinal direction of the cross flow fan.
The rising dimension of each short side is the rising dimension of each cover.
It is a configuration that is much larger than the law .

[0009]

The cross-flow fan according to the present invention comprises a cover provided on the peripheral surfaces of both ends of the impeller as described above,
By disposing the pair of U-shaped rectifying plates, a turbulent flow serving as a starting point of surging does not occur on both end surfaces of the cross flow fan, and the surging resistance is improved.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. The same or corresponding parts as those in FIG. 3 are denoted by the same reference numerals, and a description thereof will be partially omitted. Also, as compared with the one in FIG. 3, there is no significant difference in the basic configuration, only the positions of the combustion device 3 and the cross flow fan 5 are upside down.

FIG. 2 is a detailed view of a cross-flow fan according to an embodiment of the present invention. One end of the impeller 5 is connected to the drive motor 7, and a shaft 5 a provided at the other end is supported by a bearing 21. The outer periphery of the impeller 5 has a guide plate 12 for guiding the flow direction and a stabilizing plate 13 for stably holding a vortex center 22 formed at the center of the flow of the impeller 5 parallel to the rotation axis direction of the impeller 5. disposed on, and clamped by the side plate 16 and the side plate 17 to form the air passage in the axial direction of the blades car 5.

A burring hole is formed in the side plate 16 inwardly of the impeller 5 so as to cover an end peripheral surface of the impeller 5 to form a cover body 16a. Further, the other side plate 17 is provided with a cylindrical ring-shaped cover 18 so as to cover the peripheral surface of the other end of the impeller 5.

Further, a long side 19b having an L-shaped cross section is provided.
The short side 19a of the straightening plate 19 having the short side 19a is provided close to the end cover body 16a of the impeller 5 at a predetermined interval . The long side 19b is the casing 16
Are arranged in parallel at an interval and extended to the end face of the outlet 15. The current plate 20 is also the current plate 1
9, the short side 20 a is the end cover body 18 of the impeller 5.
The provided close to hold a predetermined interval, further, the long side 20b are disposed to the end face of the parallel and outlet 15 to the inside apart casing 17. And black
Rising dimension of each short side when viewed in the longitudinal direction of the sflow fan
Method is larger than the rising dimension of each cover.
You.

Next, the operation will be described. When the impeller 5 rotates, the air flowing from the suction plug mouth 9 through the filter 10, passes through the impeller 5 along the vortex center 22, and flows out from the air outlet 15 along the guide plate 12. This flow is
Although the flow is substantially the same in the direction of the rotation axis of the impeller 5, a boundary layer with a slow flow exists on the side plates 5b and 5c of the impeller 5 and the reinforcing partition plate 5d. Here, the cover bodies 16a and 18 and the current plates 19 and 20 are temporarily
In other cases, when the dust adheres to the filter 10 and the flow resistance increases, and the flow rate of the air decreases, the boundary layer develops more and causes turbulence. When this turbulent flow acts as a starting point and affects the main flow area remote from the side plates 5b, 5c and the partition plate 5d, a surging phenomenon occurs there. Figure
5 is a chart showing the relationship between the static pressure coefficient and the flow coefficient,
In the conventional product indicated by, due to eddy flow at point P where the flow coefficient is small
Static pressure drop (surging) due to dynamic pressure loss
Is evident.

However, in the present invention, the side plate 5 of the impeller 5 is provided.
b, the outer circumference of both ends near 5c is covered with a cover body 16a made of a burring hole or the like and a cover body 18 made of a cylindrical ring, and is extended to the end face of the air outlet 15 to form an air path. A predetermined distance between the unit cover bodies 16a and 18
By arranging the right and left rectifying plates 19 and 20 close to each other while maintaining the gap, flow does not occur near the side plates 5b and 5c at both ends of the impeller 5, so that the boundary layer serving as a starting point of surging is provided. Will be exhausted with little development. According to FIG. 5, the product of the present invention indicated by a solid line has a low static pressure.
Lower (surging) occurs at point P where the flow coefficient is small
Unlike the conventional product, it reduces dynamic pressure loss due to eddy current.
It is clear that no static pressure drop (surging) occurs.
Is.

[0016]

As described above, according to the present invention, a pair of rectifying plates having an L-shaped cross section is further provided by forming and disposing the cover body covering the peripheral surface of the blade vehicle end serving as the starting point of surging. Each short side of the casing is kept close to the above-mentioned cover body at a predetermined distance , and each long side is arranged in parallel on both inner sides of the casing at an interval and in the longitudinal direction of the cross flow fan.
Look at the rising dimension of each short side above the rising of each cover body
The cover body is designed to minimize the flow near the side plate at the end of the vane by making it larger than the dimensions.
Mainly suppresses the turbulence of the airflow at the suction section, and the rectifying plate mainly
The turbulence of the flow is suppressed, so that the filter is clogged, and even if the air path resistance increases, the decrease in the ventilation performance due to the surging phenomenon is significantly reduced. That is, there is an effect that improvement in surging resistance is achieved.

[Brief description of the drawings]

FIG. 1 shows an overall schematic view of an embodiment of the present invention, wherein a is a front view and b is a side view.

FIG. 2 is a detailed view of the cross flow fan according to the embodiment of the present invention, wherein a is a front view and b is a side view.

FIG. 3 is an overall schematic diagram showing an example of the related art.

FIG. 4 is a detailed view of a cross flow fan according to one embodiment of the prior art, wherein a is a side view and b is a front view.

FIG. 5 The relationship between the static pressure coefficient and the flow coefficient of the product of the present invention and the conventional product
Chart showing staff

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main body 2 Air duct 3 Combustion device 4 Heat exchanger 5 Cross flow fan (impeller) 7 Motor 15 Outlet 16 Side surface of casing 16a Cover body by burring hole etc. 17 Side surface of casing 18 Cover body 19 Straightening plate 19a Short side 19b Long side 20 Rectifier plate 20a Short side 20b Long side

Claims (1)

(57) [Claims] 1. A hot air heater comprising an air duct formed in a main body, a combustion device disposed in the air duct, and a cross flow fan for exchanging heat with the combustion device and exhausting air. On the side of the fan casing on the side of the motor that drives the impeller, a cover body such as a burring hole that covers one end peripheral surface of the impeller is formed inwardly of the impeller. On the side surface, a cylindrical ring-shaped cover body covering the peripheral surface of the other end is disposed, and further, each short side of a pair of straightening plates having an L-shaped cross section including a long side and a short side is each If the long side is arranged in parallel on both insides of the casing with a certain distance between them and close to the cover body
When viewed in the longitudinal direction of the cross flow fan,
Make the rising dimension larger than the rising dimension of each of the above cover bodies.
A cross flow fan for a hot air heater.