Fan device for smoke exhauster

Abstract

A fan device for a smoke exhauster includes a housing having an upper plate and a lower plate, and the upper plate is secured to a motor and rotated by the motor, the lower plate includes a bore to allow an air to flow into the housing of the fan device, and a number of fan blades secured between the upper plate and the lower plate and each fan blade include a curved bottom edge to allow the air to flow into the chamber of the fan device before contacting with the fan blades, and the fan blades each include a number of orifices for reducing a noise generated by the fan blades when the fan blades are rotated relative to the motor. The fan blades are preferably disposed inclined relative to the upper plate and the lower plate.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a smoke exhauster, and more particularly to a smoke exhauster including an improved fan device for increasing the air drawing effect thereof and for reducing the noise that may be generated by the smoke exhauster.

2. Description of the Prior Art

The applicants have developed various kinds of typical smoke exhausters which comprise one or more centrifugal fan devices each having a fan casing and a number of radially extended fan blades directly punched or forged or extended from the fan casing.

For example, U.S. Pat. No. 5,158,429 to Chiang et al. discloses one of the typical smoke exhausters comprising a number of radially extended fan blades directly punched or forged or extended from the fan casing for agitating the air or the like and for generating a circulating air. Due to the directly punching or forming of the fan blades from the fan casing, the fan blades may only be formed with a single curvature and may include a limited or a small area for actuating the air.

For increasing the air drawing effect to the fan device, the applicants have further developed various kinds of typical smoke exhausters comprising a fan device including a number of preformed fan blades to be assembled and secured between two casing members for increasing the air drawing effect to the fan devices.

For example, U.S. Pat. No. 6,866,481 to Chiang et al., and U.S. Pat. No. 6,945,753 to Chiang et al. discloses two of the typical smoke exhausters each comprising a fan device including a number of preformed and curved and suitably shaped fan blades to be assembled and secured between an upper plate and a lower plate for increasing the air drawing effect to the fan devices.

However, the fan blades include a solid structure that may generate a great noise particularly when the fan blades are rotated or driven or operated in a great speed.

The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional smoke exhausters.

SUMMARY OF THE INVENTION

The primary objective of the present invention is to provide a smoke exhauster including an improved fan device for increasing the air drawing effect thereof and for reducing the noise that may be generated by the smoke exhauster.

In accordance with one aspect of the invention, there is provided a fan device for a smoke exhauster comprising a housing including an upper plate, and a lower plate disposed below the upper plate for forming a chamber between the upper plate and the lower plate, the upper plate including a number of slits formed therein, the lower plate including a number of slots formed therein, and including a bore formed therein, and the upper plate including a casing provided therein, the chamber of the fan device being communicating with the bore of the lower plate to allow an air to flow through the bore of the lower plate and to flow into the chamber of the fan device, a motor received in the casing of the upper plate and including a spindle secured to the casing of the upper plate of the housing for allowing the casing of the housing to be rotated and driven by the spindle of the motor and to be rotated relative to the motor, and a number of fan blades disposed in the chamber which is formed between the upper plate and the lower plate of the housing, the fan blades each include an upper portion having a number of ears extended upwardly therefrom and engaged through the slits of the upper plate for securing the fan blades to the upper plate, and each include a lower portion having a number of ears extended downwardly therefrom and engaged through the slots of the lower plate for securing the fan blades to the lower plate and for securing the fan blades between the upper plate and the lower plate, and the fan blades each include a curved bottom edge curved inwardly and upwardly from the lower plate toward the upper plate to allow the air to flow into the chamber of the fan device before contacting with the fan blades, and the fan blades each include a number of orifices formed therein for allowing the air to flow through the orifices of the fan blades and for reducing a noise generated by the fan blades when the fan blades are rotated relative to the motor.

The fan blades each includes a curved outer segment, and a planar inner segment. The fan blades are preferably disposed inclined relative to the upper plate and the lower plate for increasing an air scooping effect of the fan blades.

Further objectives and advantages of the present invention will become apparent from a careful reading of the detailed description provided hereinbelow, with appropriate reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial exploded view of a fan device for a smoke exhauster in accordance with the present invention;

FIG. 2 is a bottom perspective view of the fan device for the smoke exhauster;

FIG. 3 is a bottom plan schematic view of the fan device for the smoke exhauster;

FIG. 4 is a side plan schematic view of the fan device for the smoke exhauster;

FIG. 5 is an upper plan schematic view of the fan device for the smoke exhauster;

FIG. 6 is a partial exploded and partial cross sectional view of the fan device for the smoke exhauster taken along lines 6-6 of FIG. 5, illustrating the inner structure of the fan device for the smoke exhauster.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to the drawings, and initially to FIGS. 1-5, illustrated is a fan device 1 for attaching or engaging into an outer receptacle (not shown) of a smoke exhauster in accordance with the present invention, the fan device 1 comprises a housing 10 including an upper plate 11 having a recess or depression or concave 12 formed in the upper portion thereof, or including a casing 13 provided or formed in the middle portion of the upper plate 11 and having the recess or depression or concave 12 formed in the middle portion of the casing 13 for receiving a motor 30 (FIGS. 5, 6), and including a tube or barrel or hub 14 provided or formed or extended outwardly from the middle or center portion of the casing 13 for receiving a spindle 31 that is extended outwardly from the lower portion of the motor 30 (FIGS. 1-3 and 6), and one or more fasteners 16 may be used to secure the spindle 31 of the motor 30 to the hub 14 of the casing 13.

The motor 30 may further include a frame or bracket 32 (FIGS. 5, 6) for attaching or securing to the outer receptacle (not shown) of the smoke exhauster and thus for allowing the casing 13 of the housing 10 to be rotated or driven by the spindle 31 of the motor 30 and to be rotated relative to the motor 30 and the outer receptacle of the smoke exhauster. The upper plate 11 includes a number of slits 17, 18, such as two rows or two circles of slits 17, 18 formed therein (FIGS. 1, 5) for attaching or securing a number of fan blades 40 to the upper plate 11 of the housing 10. The rows or two circles of slits 17, 18 preferably include different inclinations or are inclined relative to each other, best shown in FIG. 1. The housing 10 further includes a lower plate 20 disposed below the upper plate 11 and to be secured to the upper plate 11 with the fan blades 40, and for forming a space or chamber 21 between the upper plate 11 and the lower plate 20.

The lower plate 20 includes a bore 22 formed therein (FIGS. 1-3) and communicating with the chamber 21 of the housing 10 of the fan device 1, for allowing the air to be drawn through the bore 22 of the lower plate 20 and to be drawn into the chamber 21 of the housing 10 of the fan device 1. The lower plate 20 includes a number of slots 23 formed therein (FIGS. 1-3) and also provided for attaching or securing the fan blades 40 to the lower plate 20 of the housing 10. Each of the fan blades 40 include an upper portion 41 having one or more ears 42 extended upwardly therefrom and engaged through the slits 17, 18 of the upper plate 11, and bent or secured to the upper plate 11, for securing the fan blades 40 to the upper plate 11. Each of the fan blades 40 further include a lower portion 43 having one or more ears 44 extended downwardly therefrom and engaged through the slots 23 of the lower plate 20, and bent or secured to the lower plate 20, for securing the fan blades 40 to the lower plate 20.

The fan blades 40 may thus be solidly attached and secured between the outer peripheral portion of the upper plate 11 and the lower plate 20. As shown in FIG. 1, each of the fan blades 40 include a curved lower or bottom portion or edge 45 curved inwardly and upwardly from the lower plate 20 toward the upper plate 11 and/or the casing 13 of the housing 10. As shown in FIGS. 1-3, each of the fan blades 40 include a first or outer curved segment 46 and a second or inner planar segment 47 for scooping the air in the chamber 21 of the housing 10. It is preferable that the curved outer segment 46 of the fan blade 40 includes a width equals to or greater than that of the lower plate 20 of the housing 10, but smaller than that of the planar inner segment 47 of the fan blade 40. The above-described structure for the housing 10 of the fan device 1 has been disclosed and patented in U.S. Pat. No. 6,945,753 to Chiang et al.

The fan blades 40 of the housing 10 of the fan device 1 each further include a number of orifices 48 formed therein for allowing the air to flow through the orifices 48 of the fan blades 40 and for reducing the noise that may be generated by the fan blades 40 when the fan blades 40 are rotated or driven or operated in a great speed. The fan blades of the typical fan devices have no noise reducing orifices formed in the fan blades such that the fan blades of the typical fan devices may generate great noises particularly when the fan blades are rotated or driven or operated in a great speed. It is to be noted that a single fan device 1 has been shown and illustrated in FIGS. 1-6 of the drawing figures, and the smoke exhauster may include two or more fan devices 1 attached to the outer receptacle of the smoke exhauster and each driven by one motor 30.

It is further to be noted that the fan blades 40 are shown in the drawing figures to be secured between the upper plate 11 and the lower plate 20, and the fan blades 40 may be disposed or arranged perpendicular to the upper plate 11 and the lower plate 20, or the fan blades 40 may be arranged or disposed to be tilted or inclined relative to the upper plate 11 and the lower plate 20, best shown in FIGS. 4 and 6, for increasing the air drawing or scooping effect of the fan blades 40. In operation, as shown in FIGS. 1-3 and 6, due to the formation or provision of the curved lower or bottom edges 45 of the fan blades 40, the fan device 1 may include a widely opened lower portion formed and defined by the bore 22 of the lower plate 20 and the chamber 21 of the fan device 1, for allowing the air to flow through the bore 22 of the lower plate 20 and deeper into the chamber 21 of the fan device 1, before the air may be contacted and scooped by the fan blades 40.

The formation or provision of the orifices 48 in the fan blades 40 allows the air to flow through the orifices 48 of the fan blades 40 and to reduce the noise that may be generated by the fan blades 40, and the inclination of the fan blades 40 relative to the upper plate 11 and the lower plate 20 may further increase the air drawing or scooping effect of the fan blades 40.

Accordingly, the smoke exhauster in accordance with the present invention includes an improved fan device for increasing the air drawing effect thereof and for reducing the noise that may be generated by the smoke exhauster.

Although this invention has been described with a certain degree of particularity, it is to be understood that the present disclosure has been made by way of example only and that numerous changes in the detailed construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as hereinafter claimed.

Claims

1. A fan device for a smoke exhauster comprising:

a housing including an upper plate, and a lower plate disposed below said upper plate for forming a chamber between said upper plate and said lower plate,

said upper plate including a plurality of slits formed therein, said lower plate including a plurality of slots formed therein, and including a bore formed therein, and said upper plate including a casing provided therein, said chamber of said fan device being communicating with said bore of said lower plate to allow an air to flow through said bore of said lower plate and to flow into said chamber of said fan device,

a motor received in said casing of said upper plate and including a spindle secured to said casing of said upper plate of said housing for allowing said casing of said housing to be rotated and driven by said spindle of said motor and to be rotated relative to said motor, and

a plurality of fan blades disposed in said chamber which is formed between said upper plate and said lower plate of said housing, said fan blades each including an upper portion having a plurality of ears extended upwardly therefrom and engaged through said slits of said upper plate for securing said fan blades to said upper plate, and each including a lower portion having a plurality of ears extended downwardly therefrom and engaged through said slots of said lower plate for securing said fan blades to said lower plate and for securing said fan blades between said upper plate and said lower plate, and

said fan blades each including a curved bottom edge curved inwardly and upwardly from said lower plate toward said upper plate to allow the air to flow into said chamber of said fan device before contacting with said fan blades, and said fan blades each including a plurality of orifices formed therein for allowing the air to flow through said orifices of said fan blades and for reducing a noise generated by said fan blades when said fan blades are rotated relative to said motor.

2. The smoke exhauster as claimed in claim 1, wherein said fan blades each includes a curved outer segment, and a planar inner segment.

3. The smoke exhauster as claimed in claim 1, wherein said fan blades are disposed inclined relative to said upper plate and said lower plate for increasing an air scooping effect of said fan blades.