BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is an exploded diagram illustrating a centrifugal fan apparatus according to a preferred embodiment of the invention.
FIG. 1B is a schematic diagram showing a centrifugal fan apparatus of the invention.
FIG. 2A is a top view of an impeller having airfoil blades of signal-blade design according to the present invention.
FIG. 2B is a top view of an impeller having airfoil blades of dual-blade design according to the present invention.
FIG. 3A is a top view of a centrifugal fan apparatus according to the present invention.
FIG. 3B is a cross sectional view of a centrifugal fan apparatus according to the present invention.
FIG. 4 is a P-Q curve diagram illustrating the comparison between a centrifugal fan apparatus of the invention and other conventional centrifugal fan apparatuses.
FIG. 5 is a schematic diagram showing a dust-collecting module according to a preferred embodiment of the invention.
FIG. 6A is a schematic diagram showing a case of a ducts-collecting module according to a preferred embodiment of the invention.
FIG. 6B is an exploded diagram depicting a case of a ducts-collecting module according to a preferred embodiment of the invention.
FIG. 7 is a schematic diagram showing a dust-collect lid according to a preferred embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
For your esteemed members of reviewing committee to further understand and recognize the fulfilled functions and structural characteristics of the invention, several preferable embodiments cooperating with detailed description are presented as the follows.
Please refer to FIG. 1A and FIG. 1B, which are respectively an exploded view and a pictorial view of a centrifugal fan apparatus according to a preferred embodiment of the invention. As seen in FIG. 1A and FIG. 1B, the centrifugal fan apparatus 1 is comprised of a housing 10, an impeller 11 and a driving device 14, in which the housing is further composed of a top shell 101 and a bottom shell 102. Apart from the helical casing, as that disclosed in EPC Pat. No. EP0943808, the axial cross section of an accommodating space formed by the assembling of the top shell 101 and the bottom shell 102 is shaped as a disc, which is different from those of prior arts, whereas an intake hole 1011 is formed at the center of the top shell 101; and an outflow hole 1021 is formed at a side of the bottom shell 102.
Moreover, the impeller 11 is disposed inside the accommodating space, which is composed of: a back panel 110; a plurality of blades 113, arranged on the back panel 110; and a top panel 112, arranged over the plural blades 113. The plural blades 113 can be arranged on the back panel 111 by manner as those illustrated in FIG. 2A and FIG. 2B. However, it is only used as illustration and is not limited thereby. In FIG. 2A, the plural blades 113 are radially arranged while each blade 113 used in the impeller 11 is an airfoil blade of signal-blade design. In FIG. 2B, the plural blades 113a, 113b are radially arranged while each blade used in the impeller 11a are two offset airfoil blades 113a, 113b, i.e. blade of dual-blade design. In addition, the driving device 14 is connected to the impeller 11 by a pin 12 and an interfacing panel 13 so that the impeller 11 can be driven to rotate by the driving device 14.
Please refer to FIG. 3A, which is a top view of a centrifugal fan apparatus according to the present invention. In FIG. 3A, the manner that the impeller 11 is being arranged inside the housing 10 is illustrated. As the axial cross section of the accommodating space of the housing 10 is shaped like a disc, an airflow channel 103 of uniform width D can be formed between a rim of the impeller 11 and a side wall of the housing 10. Please refer to FIG. 3B, which is a cross sectional view of a centrifugal fan apparatus according to the present invention. In FIG. 3B, the accommodating space is being divided into a first space A1 and a second space A2 by a virtual cross section 8 passing the axial center of the impeller 11 while enabling the first space A1 to be asymmetrical to the second space A2. As seen in FIG. 1B and FIG. 3B, a helical airflow channel 1022 is formed in the second space A2 by the bottom shell 102 whereas the sectional area of the helical airflow channel 1022 is increasing progressively from the beginning thereof to the outflow hole 1021. In FIG. 3B, two sections 1022a, 1022b are shown whereas the section 1022a is at a position near the outflow hole 1021 and the section 1022b is at a position near the beginning thereof, in which the area of the section 1022a is larger than that of the section 1022b.
As there will be no obvious casing tongue by the housing design of the invention, most of the air flow will be discharged from the portion of the airflow channel under the impeller 11 so that no backflow will be generated between the intake and outflow and thus noise is reduced. Please refer to FIG. 4, which is a P-Q curve diagram illustrating the comparison between a centrifugal fan apparatus of the invention and other conventional centrifugal fan apparatuses. In FIG. 4, curve 90 represents the P-Q curve of a centrifugal fan apparatus of the invention, marked as MSL II; curve 91 represent the P-Q curve of a centrifugal fan apparatus disclosed in TW Pat. No. M246471, marked as RV-10; and curve 92 represent the P-Q curve of a centrifugal fan apparatus disclosed in EP0943808, marked as Karcher; and curve 93 represent the P-Q curve of a centrifugal fan apparatus of a current product, i.e. I-robot. As seen in FIG. 4, the performance of the centrifugal fan device of the invention is better than those other conventional centrifugal fan apparatuses, as the curve 90 is outperforming the curves 91, 92, 93. In addition, the overall noise of the invention is about the same as that of Karcher, but is much better than that of RV-10 by about 10 dB. Hence, the centrifugal fan apparatus of the invention is considered to be a low noise, high flow rate centrifugal fan apparatus.
As the aforesaid centrifugal fan apparatus of the invention is capable of providing high flow rate while maintaining high pressure difference, the centrifugal fan apparatus is suitable to be adapted for a duct-collecting module. Please refer to FIG. 5, which is a schematic diagram showing a dust-collecting module according to a preferred embodiment of the invention. The duct-collecting module 2 is composed of a centrifugal fan apparatus 20 and a dust-collecting case 21, in which the centrifugal fan apparatus 20 can be the one disclosed hereinbefore. Please refer to FIG. 6A and FIG. 6B, which are respectively a schematic diagram and an exploded diagram showing a case of a ducts-collecting module according to a preferred embodiment of the invention. The ducts-collecting case 21 further comprises: a case 210, having a recess 2104 and a through hole 2101 channeling to the recess 2104; a dust-collecting lid 212; and a box 211; wherein, a side of the case 210 is arranged with a groove hole 2102 channeling to the recess 2104; the through hole is channeled to the intake hole of the centrifugal fan apparatus 20 while an extractable filtering device is arranged between the through hole 2102 and the centrifugal fan apparatus 20.
The box 211 is formed with a dust-collecting space 2110, which is capable of being received in the recess 2104 as a drawer while enabling the duct-collecting space to channel with the through hole 2102 and the groove hole 2101. By which, a duct-collecting bag received in the duct-collecting space can be easily accessed and replaced as the box 211 can be easily pulled out of the recess 2104. Please refer to FIG. 7, which is a schematic diagram showing a dust-collect lid according to a preferred embodiment of the invention. As seen in FIG. 7, an intake 2121 and an outflow 2120 are formed on the dust-collecting lid 212 while the intake 2121 is channeled with the groove hole 2101 of the case 210. In addition, a roller, preferred formed with brush, can be arranged at the intake 2121 of the dust-collecting lid 212.
In this preferred embodiment of the invention, for enabling air flow to flow smoothly in its airflow channel, the intake hole of its centrifugal fan apparatus is connected to the dust-collecting case 212 through the dust-collecting lid 212 while arranging the opening of the groove hole 2101 of the case 210 at a side thereof instead of at the bottom thereof, by which the airflow channel is not twist for the consideration of improving dust-collecting efficiency and thus noise is reduced. Moreover, as the case 210 and the box 211 are structured as a drawer that the box 211 can be pull out of the case easily, not only it is good for noise reduction, but also it is good for dust cleaning and filer replacing.
To sum up, the invention can provide a dust-collecting module capable of utilizing it specially designed casing to assemble a low noise, high flow rate centrifugal fan apparatus so as to be able to perform a dust-collecting operation while maintaining the smoothness of airflow in the centrifugal fan apparatus.
While the preferred embodiment of the invention has been set forth for the purpose of disclosure, modifications of the disclosed embodiment of the invention as well as other embodiments thereof may occur to those skilled in the art. Accordingly, the appended claims are intended to cover all embodiments which do not depart from the spirit and scope of the invention.
Patent Application
20080069689
