Radial tube centrifugal fan

• US 4,484,860 A
• Filed: 05/17/1982
• Issued: 11/27/1984
• Est. Priority Date: 05/17/1982
• Status: Expired due to Fees

• Current Assignee: Donaldson Company Incorporated
• Original Assignee: Donaldson Company Incorporated
• Inventors: Brenholt, David L., Mattson, Kenneth V., Fischer, Paul M.
• Primary Examiner(s): Garrett, Robert E.
• Assistant Examiner(s): Pitko, Joseph M.
• Application Number:
  US06/379,256
• Time in Patent Office: 925 Days
• Field of Search: 416/186 R, 416/179, 416/181, 416/182, 416/183, 416/184, 416/185, 29/156.8 CF
• US Class Current: 416/182
• CPC Class Codes: F04D 29/281 for fans or blowers

Abstract

A radial tube centrifugal fan is disclosed. The fan is assembled from a first mating half (12) having a planar backing plate (16) with a group of half tubes (52) extending in spoke-like fashion from the plate and separated by webbing members (56), attached to a second mating half (14) having an axial inlet opening (18) and a like group of half tubes (54) and webbing members (58). The assembled fan has an inlet port (18) and a plurality of radially extending outlet tubes (26) formed from the mating half tubes and which are curved in a direction away from the preferred direction of fan rotation.

Claims

1. A radial tube centrifugal fan comprising:

a planar backing plate having an axis of rotation perpendicular to said plate, and a perimeter;

first means defining an entry port mounted in spaced relation to and in a plane parallel to said backing plate;

means for mounting a plurality of radially extending tube means between said first means and said backing plate for drawing a fluid through said port and outwardly through said tube means during rotation of said fan about said axis of rotation in a preferred direction, said tube means each being of generally circular cross section and extending radially outwardly from said perimeter of said backing plate, said tube means each being of a diameter substantially equal to the distance between said backing plate and said entry port, and each said tube means having an end between said plate and said port;

said tube means including radially extending tubes, each having an innermost end and a centerline, each said centerline comprising a series of points, each of which is the location of the center of said tube at said point, said innermost ends being located adjacent each other with said centerlines of said tubes lying in a single plane, said innermost ends being in contact with the innermost ends of adjacent tubes, and said innermost ends forming a circle adjacent to and around said entry port;

said means defining said entry port including a bell flange means having an outer portion connected to said tubes, a circular rim portion and a depending flange portion extending toward said oppositely disposed backing plate; and

said circular rim portion being configured to define with said depending flange portion a smoothly flared air inlet port, and to further define an annular inwardly opening groove between said outer portion and said flange portion, said groove having a reinforcing ring mounted therein to reinforce said bell flange means.

2. The fan of claim 1 further wherein:

said means defining said entry port includes a ring-like flange member having a cylindrical wall substantially perpendicular to said entry port plane; and

said cylindrical wall has an inner edge disposed between said entry port plane and said plane of said centerlines to channel said fluid through said entry port so that said fluid enters near the center of said innermost ends of said tubes.

3. A radial tube centrifugal fan comprising:

a planar backing plate having an upper surface and a lower surface, and having an axis of rotation perpendicular to said plate, and a perimeter;

first means defining an entry port mounted in spaced relation to and in a plane parallel to said backing plate; and

means for mounting a plurality of radially extending tube means between said first means and said backing plate for drawing a fluid through said port and outwardly through said tube means during rotation of said fan about said axis of rotation in a preferred direction, said tube means each being of generally circular cross section and extending radially outwardly from said perimeter of said backing plate, said tube means each being of a diameter substantially equal to the distance between said backing plate and said entry port, and each said tube means having an end between said plate and said port;

said backing plate having an opening located coaxial with said axis of rotation of said backing plate; and

said backing plate having mounting means including a collar surrounding said opening on said backing plate for mounting said fan to a rotational power source; and

a plurality of radially extending inner reinforcement ridges each having an inner terminus, said ridges lying on and rising above said upper surface of said backing plate, and terminating in said collar, said collar being continuous with said inner terminus of said inner reinforcement ridges, said inner reinforcement ridges extending radially outwardly at least to said perimeter of said backing plate.