Blower wheel assembly

[57] ABSTRACT

By the present invention there is provided a blower wheel housing having generally parallel side walls including an air inlet and a wrapper connecting the side walls to form a hollow chamber. A blower wheel is located in the housing and is axially aligned with the inlet opening. Access to the blower wheel for its removal or servicing is provided by peeling back the wrapper radially away from the blower wheel.

Claims, 4 Drawing Figures

<img file="US3732030A_D0001.tif" />

IS

PATENTED**/ 81973

3,732.030

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3,732,030

BLOWER WHEEL ASSEMBLY

BACKGROUND OF THE INVENTION

The present invention relates to a blower housing construction containing a blower wheel and drive motor, and is more particularly concerned with access to the housing interior for servicing or replacement of the blower wheel and motor. Generally the design and dimensions of a blower housing including the air inlet and outlet openings play an important part in delivering static pressure and efficiency of the blower wheel. To prevent a decrease in pressure due to leakage and recirculation around the inlet areas it is customary to design the dimension of the inlet openings to be smaller than the diameter of the blower wheel. The housing is further designed with a cut-off portion whose function it is to direct the air stream to the outlet area so as to prevent recirculation. When properly designed the shape of the cut-off, the distance it projects into the outlet and its proximity to the blower wheel usually results in outlet dimensions that are smaller than the diameter of the blower. The above design requirements generally prevent the removal of the blower wheel from the housing, and access to it is very difficult without resorting to construction that requires separate and removable parts.

These design restrictions have resulted in many attempts to design housings wherein means are provided in which blower wheels may be removed for service. One approach is shown in U.S. Pat. No. 3,627,442 — Brandt issued Dec. 12, 1971 and assigned to General Electric, assignee of the present invention wherein the blower housing is disassembled to obtain access to the blower wheel. Some of the other attempts to gain access to the blower wheel have been in providing separate parts. For example, In U.S. Pat. No. 1,978,459 issued Oct. 30, 1934, removable inlet rings have been used to cover larger openings that would allow the blower wheel to pass through. Another approach as shown in U.S. Pat. No. 3,191,851 issued June 29,1965, has been to use two-piece wrappers wherein a separate piece has been used in the cut-off area adjacent the outlet of the housing, thus allowing the blower wheel to be removed through the outlet area.

While these attempts have provided access to the blower wheel for replacement and service, they have resulted in undue increase in manufacturing, material and fabrication cost. It is therefore an object of this invention to provide an improved blower wheel housing wherein access to the blower wheel is provided without removing structural parts from the housing.

SUMMARY OF THE INVENTION

A blower housing is provided having generally parallel side walls and an air inlet opening in at least one of the side walls. A one-piece wrapper connects the side walls to form the peripheral wall on the housing. The blower wheel is located in the housing and is axially aligned with the inlet opening. One of the ends of the peripheral wall is radially spaced from the blower while the other end is located tangentially and spaced apart from the radial end to form the outlet. In the present embodiment only a portion of the wrapper including the tangentially disposed end is permanently secured to the side walls, the remaining portion of the wrapper including the radially disposed end is arranged to rest on support means provided on the inner surface of the side walls with the radially disposed end removably attached thereto.

To service or remove the blower wheel from the blower housing, the radially disposed end of the wrapper is released from the side walls and the portion of the wrapper resting on the support means is moved radially from the blower wheel without disturbing the side walls.

BRIEF DESCRIPTION OF THE DRAWING

One embodiment of the present invention is illustrated in the accompanying drawings wherein:

FIG. 1 is a perspective elevational view of one embodiment of the invention removed from the mounting plate;

FIG. 2 is an end elevational view of the blower housing with parts broken away to show the interior of the housing;

FIG. 3 is an exploded perspective view showing the main parts of the blower housing in detail; and

FIG. 4 is a fragmentary sectional view taken along line 4—4 of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to FIGS. 1 and 2 there is illustrated a blower housing assembly 11 employing an embodiment of the present invention. The blower housing 11 comprises a pair of spaced apart parallel end walls 12 and 13, each of which is shown with an air inlet 14 and 15 respectively and a one-piece wrapper 16. The wrapper 16 is generally scroll shaped with an outer peripheral wall 17 having its axially disposed edges 18 extending to the end walls to form a hollow housing. The peripheral wall 17 of wrapper 16 extends from a radially spaced end 19 and continues circumferentially to a generally flat tangentially disposed portion 21 arranged parallel to a cut-off section 22 projecting radially outwardly from the end 19 and spaced therefrom to form a tangential outlet 23. The blower assembly 11 includes a rotatable blower 24 and a motor 26 for driving the blower wheel 24. The drive motor 26 is provided with an output shaft which is fastened to the center of the blower wheel partition. In the embodiment shown herein the blower 24 is supported by the drive shaft of the motor, with the motor 26 positioned on one of the air inlets 15 in the end wall 13. The motor 26 is supported by a series of radially spaced supporting arms 27. Each of the arms 27 includes an ear 28 which is fastened to the arms 27 and the end wall 13 in a manner to allow air space around the motor housing and into the blower wheel.

The blower housing 11 may be used in conjunction with a forced air furnace (not shown) or similar appliance that requires the movement of air. FIG. 1 shows one means of mounting the blower housing 11 for use in a suitable appliance. A mounting plate 30 suitably dimensioned and oriented to supply the proper movement of air to an appliance is provided with an air outlet or opening 31. Two opposite and generally parallel sides of the opening 31 are provided with the depressed tracks or support flanges 32. A third or rear side is provided with the similar support flange 33. To support the blower housing 11 on the mounting plate 30 the top

3,732,030 edges of the side walls 12 and 14 are provided with flanges 34 which are slidably supported on tracks 32 (FIG. 2) while the tangentially disposed portion 21 of the peripheral wall 17 has a flange 36 which is supported on the front flange 33 when the assembly 11 is located on plate 30. It will be apparent that the blower housing 11 may be installed or removed from the mounting plate 30 by simply sliding the flanges 34 of the housing 11 into or out along the track members 32.

Referring now to FIG. 3, the side walls 12 and 13 have substantially straight edges or portions 37 and 38 extending downwardly from the ends of the flanges 34 and merge with a generally semi-circular or arcuate bottom edge or portion 39. The peripheral edges of portions 37, 38 and 39 of each end wall are bent axially outwardly to form a flange or support 41. Starting at the peripheral end 19, a portion of the axially disposed ends 18 of the wall 16 are permanently secured as by welding or other suitable means, to the support flange 41 along the straight edge portion 38 to form the tangential wall 21 leading to the outlet 23, and continuing along arcuate portion 39 to the approximate tangent point of 39 and 37. The remaining portion of the wrapper 16 is provided with a reduced axial dimension so as to fit between the end walls 12 and 13 to complete the peripheral wall 17 of the housing 11. To insure that peripheral wall 17 of the wrapper 16 continues in a scroll-like configuration beyond the arcuate portion 39 and the tangent point of 39 and 37, the side walls 12 and 13 are provided with a support means or tabs 42. The tabs 42 are arranged, starting generally in the area of the tangent point of 39 and 37, and continue in a line simulating a scroll shape around the inlet openings 14 and 15 on each of the end walls 12 and 13. Each of the support means or tabs 42 is formed by lancing the side walls and pushing the stock below the lance axially inwardly to form a plurality of support surfaces. In the final assembly step of the blower housing, the portion of the peripheral wall 17 that is not welded to the side walls, as heretofore mentioned, is inserted between the side walls 12 and 13 and onto the support tabs as shown in FIG. 4. The portion of the peripheral wall 17 resting on the support tabs is removably held in this position by fastening the end 19 of the peripheral wall 17 to the side walls in the following manner.

Holding means 43 are provided on the axial edge 18 adjacent the end 19 of the peripheral wall 17 to receive sheet metal screws 44 that are adapted to be inserted through holes 45 in the side walls 12 and 13. The holding means 43 consists of groups of parallel slits with the stock between the slits being offset alternately in opposite directions to form generally semi-circular tongues 46 which define in effect a recess for the reception of the screws 44. The screw threads and the offsetting of the tongues 46 are dimensioned so that the screw 44 is forced into the space between them to effectively hold the wrapper 16 in its scroll shape configuration. In practice, to service the motor or blower it is merely necessary to remove screws 44 and peel back the peripheral wall portion supported on tabs 42 to the position indicated by dotted lines in FIG. 3.

The portion of the side walls disposed outside of the blower housing may be provided as illustrated in FIGS. 1 and 3 with openings 47 of various dimensions and shapes. The openings 47 as illustrated in the present embodiment are utilized for mounting a motor capacitor 48 and quick disconnect devices 49 which would allow the removal of the blower housing from the mounting plate 30 and appliance by unplugging the electrical connections. Other of the openings 47 may be dimensioned to support other components that may be utilized in the operation of the appliance in which the blower housing 11 may be installed.

From the foregoing description it will be apparent that the present invention provides a one piece wrapper 16 having a portion of its peripheral wall 17 arranged to be removably fastened between the side walls 12 and 13 of the housing 11 so as to be movable from a position wherein it is part of the peripheral wall of the blower housing to a position away from the blower assembly and out from between the side walls 12 and 13 to afford access to the housing interim and the blower wheel assembly for removal or servicing.

While in accordance with the Patent Statutes, there has been described what, at present, is considered to be the preferred embodiment of this invention, it will be obvious to those skilled in the art that various changes and modifications may be made thereto without departing from the invention, and it is intended therefore in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of this invention.