Patent Grant
6964556
1. Field of the Invention
The invention relates to a side-blown fan and, more particularly, to a side-blown fan with reduced air leakage and an increased air pressure.
2. Description of the Related Art
In a system requiring a high back pressure, a blower is conventionally used to provide a higher air pressure for the system so that a higher back pressure may be obtained in the system.
In the above-mentioned structure, the upper and lower cases 102a and 102b and an outer periphery of the blade member 106 defines a region serving as a flow field 114 for the blower 100. Since the upper and lower cases 102a and 102b almost do not cover the blade member 106, when the rotating speed of the blade member 106 is gradually increased, the air stream flowing in the flow field 114 tends to overflow from the inlets 104, 110, and pressure leakage and air leakage may occur. Accordingly, the air pressure cannot be further increased.
It is therefore an object of the invention to provide a side-blown fan to greatly increase the operational air pressure.
To achieve the above-mentioned object, the invention provides a side-blown fan formed by a case and a blade member. The case includes a side-outlet, an axial inlet, and a protrusion extending from an edge of the axial inlet toward the center of the axial inlet. The blade member is embedded inside the case. A high air pressure region exists between the blade member and the case in a radial direction. The protrusion covers the high air pressure region and a part of the blade member.
Also, the side-blown fan of the invention may further include another axial inlet and another protrusion, which are formed on another side surface corresponding to the first axial inlet and the first protrusion. Furthermore, the case of the side-blown fan of the invention may also be constituted of a plurality of case elements.
In the side-blown fan of the invention, the protrusion covers the high air pressure region and a part of the blade member. Therefore, when the side-blown fan is in operation, the air traveling within the flow field of the side-blown fan will not overflow from the flow field, and the operational air pressure may be greatly increased.
In addition, in the side-blown fan of the invention, since the protrusion extends from the edge of the axial inlet toward the center, the dimension of the axial inlet is slightly reduced. However, the operational air pressure may be greatly increased within the range of the specific air flow.
Other objects, features, and advantages of the invention will become apparent from the following detailed description of the preferred embodiment with reference to the accompanying drawings.
A side-blown fan of the invention will be described in the form of a blower. Referring to
The case 202 has a side-outlet 214, axial inlets 204 and 212, and protrusions 206a and 206b. The protrusions 206a and 206b extend from edges of the axial inlets 204 and 212 toward the centers of the axial inlets 204 and 212, respectively. The axial inlets 204 and 212 correspond to each other, and the protrusions 206a and 206b also correspond to each other. The case 202 is made from, for example, a plastic, metallic or composite material. Also, the case 202 can be formed by way of injection molding, press forming, cutting, or the like. In one embodiment, case elements 202a and 202b are formed by way of injection molding and then combined. In addition, each of the axial inlets 204 and 212 may be shaped to be substantially circular.
The case elements 202a and 202b may be combined by way of clamping, riveting, engaging, adhering, or the like. Specifically, the case element 202a has extending hooking structures and the case element 202b has corresponding eye structures so that the hooking structures and the eye structures are engaged to combine the case elements 202a and 202b. Alternatively, in another embodiment, the case element 202a has extending U-shaped structures and the case element 202b has corresponding bump structures so that the U-shaped structures and the bump structures are engaged to combine the case elements 202a and 202b.
The blade member 208 is embedded inside the case 202, and has a plurality of blades 216 and a driving device (not shown) for driving the blades 216. In the radial direction, a flow field 218 exists between the blade member 208 and the case 202, wherein there is a high air pressure region 210 in the flow field 218. The high air pressure region 210 means a narrower region existing between the blade member 208 and the case 202 in the radial direction. Specifically, the high air pressure region 210 is a flow region extending from the narrowest section of the flow field 218 to a section at a prescribed distance of the flow field 218 along the direction of the operational air stream inside the case 202. The prescribed distance depends on requirements in actual practice.
The protrusions 206a and 206b cover the high air pressure region 210 and a part of the blade member 208, wherein the range of the specific region varies according the required air pressure. The protrusion 206a (or 206b), as shown in
In the side-blown fan 200, the high air pressure region 210 covered by the protrusions 206a and 206b exists between the axial inlets 212 and 204. Accordingly, when the overflowing air pressure is reached, the operational air stream will be blocked by the protrusions 206a and 206b and still flow within the flow field 218, thereby preventing the air leakage. Therefore, a higher operational air pressure can be obtained under the same rotating speed, and even the rotating speed of the fan may be further increased to get a higher operational air pressure.
Next, the effect of the side-blown fan of the invention will be described with reference to
It can be seen from
In the side-blown fan of the invention, since the protrusion covers the high air pressure region 210 and a part of the blade member 208, when the side-blown fan is in operation, the air traveling within the flow field of the side-blown fan will not overflow from the flow field, and the operational air pressure can be greatly increased.
In addition, in the side-blown fan of the invention, since the protrusion extends from the edge of the axial inlet toward the center, the dimension of the axial inlet is slightly reduced. However, the operational air pressure may be greatly increased within the range of the specific airflow.
Moreover, although the case 202 in accordance with the embodiment of the invention is formed by combining at least two case elements, the case 202 may also be integrally formed.
Furthermore, although the case 202 of the invention has two axial inlets in accordance with the embodiment, the case 202 may have only one axial inlet.
While the invention has been described by way of an example and in terms of a preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiment. To the contrary, it is intended to cover various modifications. Therefore, the scope of the appended claims should be accorded the broadest interpretation so, as to encompass all such modifications.
| Number | Date | Country | Kind |
|---|---|---|---|
| 92204948 U | Mar 2003 | TW | national |
| Number | Name | Date | Kind |
|---|---|---|---|
| 6328529 | Yamaguchi et al. | Dec 2001 | B1 |
| 6540476 | Huang et al. | Apr 2003 | B2 |
| 6805536 | Hung | Oct 2004 | B2 |
| Number | Date | Country | |
|---|---|---|---|
| 20040191060 A1 | Sep 2004 | US |
