Centrifugal fan impeller structure

Abstract

A centrifugal fan impeller structure includes a hub having multiple blades. The blades extend from a circumference of the hub in a direction away from the hub. Each two adjacent blades define therebetween a flow way, an air outlet and an air inlet. The air outlet and the air inlet are respectively positioned at two ends of the flow way in communication with the flow way. The air outlets are arranged at unequal intervals so as to greatly reduce noise in operation.

Claims

1. A centrifugal fan impeller structure comprising: a hub having multiple blades, each of the blades having one end connected with a circumference of the hub and extending from the circumference of the hub in a direction away from the hub, another end of each of the blades being a free end and each two adjacent blades defining therebetween a flow way, an air outlet and an air inlet, the air outlet and the air inlet being respectively positioned at two ends of the flow way in communication with the flow way, the air outlets being arranged at unequal intervals; wherein each blade has a first end and a second end, the air inlet being defined between the first ends of each two adjacent blades, the air outlet being defined between the second ends of each two adjacent blades; wherein the first ends together define a first pitch circle, a tangent of the first pitch circle at the first end being defined as a first tangent, the blade having a blade central line, a tangent of the blade central line at the first end being defined as a second tangent, the second tangent intersecting the first tangent to contain an air incoming angle; wherein the second ends together define a second pitch circle, a tangent of the second pitch circle at the second end being defined as a third tangent, the blade having a blade central line, a tangent of the blade central line at the second end being defined as a fourth tangent, the fourth tangent intersecting the third tangent to contain an air outgoing angle, the air outgoing angles of the blades being unequal; and wherein the air outlets at the free ends of the blades are arranged un-equidistantly; and wherein the blades have a similar curved shape, and the first ends of the blades have equal widths.

2. The centrifugal fan impeller structure as claimed in claim 1, wherein the second ends have unequal widths.

3. A centrifugal fan impeller structure comprising: a hub having multiple blades, each of the blades having one end connected with a circumference of the hub and extending from the circumference of the hub in a direction away from the hub, another end of each of the blades being a free end and each two adjacent blades defining therebetween a flow way, an air outlet and an air inlet, the air outlet and the air inlet being respectively positioned at two ends of the flow way in communication with the flow way, the air outlet being arranged at unequal intervals; wherein each blade has a first end and a second end, the air inlet being defined between the first ends of each two adjacent blades, the air outlet being defined between the second ends of each two adjacent blades; wherein the first ends together define a first pitch circle, a tangent of the first pitch circle at the first end being defined as a first tangent, the blade having a blade central line, a tangent of the blade central line at the first end being defined as a second tangent, the second tangent intersecting the first tangent to contain an air incoming angle; wherein the second ends together define a second pitch circle, a tangent of the second pitch circle at the second end being defined as a third tangent, the blade having a blade central line, a tangent of the blade central line at the second end being defined as a fourth tangent, the fourth tangent intersecting the third tangent to contain an air outgoing angle; wherein the air outlets at the free ends of the blades are arranged un-equidistantly; wherein the blades have a similar curved shape, and the first ends of the blades have equal widths; and wherein at least one of the blades has a length unequal to that of the other blades.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein:

(2) FIG. 1 is a perspective view of a first embodiment of the centrifugal fan impeller structure of the present invention;

(3) FIG. 2 is a top view of the first embodiment of the centrifugal fan impeller structure of the present invention;

(4) FIG. 3 is a top view of a second embodiment of the centrifugal fan impeller structure of the present invention; and

(5) FIG. 4 is a top view of a third embodiment of the centrifugal fan impeller structure of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(6) Please refer to FIGS. 1 and 2. FIG. 1 is a perspective view of a first embodiment of the centrifugal fan impeller structure of the present invention. FIG. 2 is a top view of the first embodiment of the centrifugal fan impeller structure of the present invention. According to the first embodiment, the centrifugal fan impeller structure of the present invention includes a hub 11 having multiple blades 111 with generally similar curved shapes.

(7) The blades 111 extend from a circumference of the hub 11 in a direction away from the hub 11. Each two adjacent blades 111 define therebetween a flow way 111a, an air outlet 111b and an air inlet 111c. The air outlet 111b and the air inlet 111c are respectively positioned at two ends of the flow way 111a in communication with the flow way 111a. The air outlets 111b are arranged at unequal intervals.

(8) Each blade 111 has a first end 1111 and a second end 1112. The air inlet 111c is defined between the first ends 1111 of each two adjacent blades 111. The air outlet 111b is defined between the second ends 1112 of each two adjacent blades 111.

(9) The first ends 1111 together define a first pitch circle 12. A tangent of the first pitch circle 12 at the first end 1111 is defined as a first tangent 13. The blade 111 has a blade central line 1113. A tangent of the blade central line 1113 at the first end 1111 is defined as a second tangent 14. The second tangent 14 intersects the first tangent 13 to contain an air incoming angle 15.

(10) The second ends 1112 together define a second pitch circle 16. A tangent of the second pitch circle 16 at the second end 1112 is defined as a third tangent 17. A tangent of the blade central line 1113 at the second end 1112 is defined as a fourth tangent 18. The fourth tangent 18 intersects the third tangent 17 to contain an air outgoing angle 19. In this embodiment, the second ends 1112 have unequal widths.

(11) That is, the blades 111 with two different widths are alternately annularly disposed on the circumference of the hub 11, whereby the air outlets 111b are arranged at unequal intervals.

(12) Please now refer to FIG. 3, which is a top view of a second embodiment of the centrifugal fan impeller structure of the present invention. The second embodiment is partially identical to the first embodiment in structure and thus will not be repeatedly described hereinafter. The second embodiment is different from the first embodiment in that the air outgoing angles 19 are unequal. That is, the air outgoing angles 19 of at least two blades 111 are unequal to each other. The blades 111 with two different air outgoing angles 19 can be alternately annularly disposed on the circumference of the hub 11.

(13) Please now refer to FIG. 4, which is a top view of a third embodiment of the centrifugal fan impeller structure of the present invention. The third embodiment is partially identical to the first embodiment in structure and thus will not be repeatedly described hereinafter. The third embodiment is different from the first embodiment in that at least one of the blades 111 has a length unequal to that of the other blades 111.

(14) The present invention has been described with the above embodiments thereof and it is understood that many changes and modifications in the above embodiments can be carried out without departing from the scope and the spirit of the invention that is intended to be limited only by the appended claims.