US3775029A

US3775029A - Direct driven blower

Info

Publication number: US3775029A
Application number: US00224761A
Authority: US
Inventors: J Ranz
Original assignee: Lau Inc
Current assignee: Lau Inc
Priority date: 1972-02-09
Filing date: 1972-02-09
Publication date: 1973-11-27
Anticipated expiration: 1990-11-27
Also published as: CA969903A

Abstract

Direct driven blowers include end walls in which the venturi opening is formed in the end walls and in which the motor is supported directly on inwardly-extending fingers or flanges which are formed integrally with one of the end walls. The motor support flanges are formed concurrently with the forming of the end wall and the arrangement eliminates the usual separate motorsupport bracket commonly used in direct drive blower arrangements. Embodiments of the invention include vibration isolation between the motor and the end wall flanges and between the end wall and the remaining housing structure. In one embodiment, the blower housing end wall is formed in two parts including an inner removable part defining the venturi opening and supporting the blower motor, and an outer part, these parts being formed from a single blank.

Description

[ Nov. 27, 1973 United States Patent 1191 Ranz [ DIRECT DRIVEN BLOWER Primary Examiner-Henry F. Raduazo [75] Attorney-Lawrence B. Biebel et al.

Inventor: James R. Ranz, Wilmington, Ohio Ohio [57] ABSTRACT Direct driven blowers include end walls in which the Dayton [73] Assignee: Lau Incorporated,

Filed:

Feb. 9, 1972 venturi opening is formed in the end walls and in which the motor is supported directly on inwardlyextending fingers or flanges which are formed integrally with one of the end walls. The motor support he forming of the end wall and the arrangement eliminates t 8 9 5 l 4 3 2 4 7 1 4 3 5 3 7 l 4 1 m 6 u n 4 m 2 H 2 H o N L L C W s A U .1 .l .1 2 2 5 flanges are formed concurrently with t he usual separate motor-support bracket commonly used in direct drive blower arrangements. Embodiments of the invention include vibration isolation between the References Ciied motor and the end wall flanges and between the end UNITED STATES PATENTS wall and the remaining housing structure. In one em- 417/363 bodiment, the blower housing end wall is formed in 4 7 23 two parts including an inner removable part defining Tweedy 417/353 the venturi opening and supporting the blower motor,

Bullock............. 416/178 and an outer part, these parts being formed from a single blank.

3,698,833 2,521,638 9/1950 Lamm....

11 Claims, 15 Drawing Figures PATENTEDHHV 27 I975 sum 10F 4 FIG-3 PATENTED NOV 2 7 I975 SHEET 2 OF 4 PAIENIEUnuv'z? 1975 V 3.775.029 sum u [1F FIG-12 DIRECT DRIVEN BLOWER BACKGROUND OF THE INVENTION The present invention is directed to direct driven blowers, and more particularly to an improved motor mounting arrangement in combination with a blower housing.

In direct driven blowers, an electric motor is mounted on the blower housing and has a direct connection to the blower wheel. A separate motor mount attachment is secured to one of the blower end walls for supporting the drive motor and the associated directly-supported blower wheel. The motor mounting frames are customarily made of strap material or wire, and are commonly formed separately from the blower housing and attach to the housing, and the motor then attaches to the frame. An example is shown in the U.S. Pat. of Burrowes, No. 2,686,630 of Aug. 17, 1954. While the separate motor support frames are satisfactory, they do present an additional cost item in the manufacture and use of direct driven blowers.

SUMMARY OF THE INVENTION The present invention is directed to a direct drive blower and to a housing for the blower in which one end wall is formed with a plurality of integral drive motor support flanges which have inner ends proportioned to be received about the drive motor and clamped or suitably attached to the motor. The motor mounting flanges are preferably formed in the one end wall of the blower housing by stamping or by other suitable metal draw forrning means directly from the end wall blank. Preferably, the wall which supports the motor also defines a venturi inlet to the blower housing, and the venturi portion of the wall is formed at the same time as are the integral motor mounting flanges. In one embodiment, the end wall in question is formed in two parts from an original stamping. The end wall thus includes an inner part within which are formed the motor support flanges and within which is defined the venturi, and having a general circumference which is somewhat greater than that of the blower wheel permitting the blower wheel to be assembled through the outer part. The inner and outer parts of the housing are divided at a common circumference line and preferably formed with integral lugs which are aligned with openings on the outer part with vibration isolation being placed therebetween.

An important object of the invention is the provision of a direct drive blower housing in which one end wall defines a plurality of drive motor support flanges which are formed integrally with the wall.

Another object of the invention is the provision, in a direct drive blower, of means in one blower wall defining a plurality of arcuately-spaced radial inwardlyextending fingers which are formed as an integral part of this wall and which defines an opening in which the motor is received for mounting directly on the fingers.

These and other objects and advantages of the present invention will become apparent from the following description, the accompanying drawings and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a direct drive blower and housing constructed according to this invention;

FIG. 2 is an outside elevation of the inner portion of the blower end wall showing the motor in place;

FIG. 3 is a side elevation of the end wall of FIG. 2;

FIG. 4 is an inside elevation of the end wall, with the motor drive shaft in section, looking from the inside of the blower housing;

FIG. 5 is a front perspective view of one of the channel-shaped motor-mounting flanges;

FIG. 6 is a rear perspective thereof;

FIG. 7 is a plan diagram of the blank from which the end wall is formed;

FIG. 8 is a transverse section through the blower housing partially broken away, showing the manner in which the inner end wall portion is attached to the outer end wall portion;

FIG. 9 is a fragmentary enlarged section of the vibration isolation attachment;

FIG. 10 is a side elevation of a modified form of the invention;

FIG. 11 is an enlarged fragmentary vertical section through one of the attaching fingers of the embodiment of FIG. 10;

FIG. 12 is a vertical section through a blower housing showing still another embodiment of the invention;

FIG. 13 is an elevational view of the end wall blank of the embodiment of FIG. 12;

FIG. 14 is an enlarged perspective of one of the motor mounting fingers of this embodiment made from the blank of FIG. 13; and

FIG. 15 is a section through the vibration isolator useful with the present invention.

DESCRIPTION OF PREFERRED EMBODIMENTS Referring to the embodiment of the invention shown in FIGS. 1-9, a centrifugal blower is illustrated generally at 10 in FIG. 1 as including a generally axiallyextending sheet metal housing 12 which is formed in the shape of a scroll. The housing 12 is closed by a pair of end walls, sometimes also known as scroll sides. One such end wall 15 is shown in FIGS. 1-9, the opposite end wall being conventional in structure. The blower 10 includes a direct drive electric motor 16 having an output shaft 17 upon which is mounted a centrifugal blower wheel 18. The wheel may be constructed according to the U.S. application of Ranz, Ser. No. 106,021, filed Jan. I3, 1971 and its precise constructions forms no part of the present invention. Preferably, both end walls are provided with openings 19 defining inlets to the blower, while the housing 12, together with the end walls, define a conventional tangential outlet 20. However, the blower 10 may also be of the single inlet type in which case the opposite wall would be closed.

As mentioned above, one of the advantages of the present invention resides in the fact that one of the end walls of the housing is formed with integral drive motor support means. In this embodiment, the end wall 15 is formed with an inner portion 22 as illustrated in FIGS. 2 and 3. The inner portion 22 may be blanked from the end wall at the same time as the end wall itself is blanked, along a circular dividing line 23 as shown in FIG. 7. The inner portion 22 is formed with an arcuately-spaced series of generally radial lugs 24, while the outer portion is correspondingly formed with an inwardly-directed series of tabs 25. After blanking, the inner portion 22 may be rotated with respect to the outer portion so that the respective lugs 24 and tabs 25 line up opposite each other. In this manner, an assembled blower motor 16 and wheel 18 may be inserted through the opening defined by the line 23, and the inner part rotated with respect to the outer part to align the respective lugs and tabs for mounting purposes.

Means integral with the inner wall portion 22 for mounting the motor 16 on the end wall 15 comprises a plurality of radially-inwardly extending arcuatelyspaced flanges or fingers 30, the blank of which is shown in FIG. 7 and the details of which are shown best in FIGS. and 6. After blanking, the arcuate space between adjacent fingers 30 is formed with a curvature, as shown at 32 in FIG. 8, and which leads smoothly into the inlet opening 19 of the blower, defining a venturi inlet. The part 22 may thus be subjected to one or more forming operations in which the final configuration of the fingers 30 as shown in FIGS. 5 and 6 and the curvature 32 are formed at the same time. The formed motor support fingers 30 thus have a radially-inwardly extending portion 34 and an inward axially-extending portion 35, and are generally channel-shaped in cross-section to provide suitable strength for supporting the motor 16 and the attached blower wheel 18. The inside surfaces 36 of the web making up the portion 35 of the fingers 30 define a motor-receiving opening which is slightly greater than the diameter of the motor itself.

The motor 16 may be removably attached to the inwardly-extending portions 35 of the fingers 30 by a simple draw band or strap 38. The band 38 extends around the motor 16 and over the tops of the portions 35 of the fingers 30 and is tightened by a suitable clamp bolt arrangement 40.

It is important to provide vibration isolation means between the motor 16 and the blower housing. In this embodiment, the isolation mounts 42 as shown in FIG. 9 are associated with the lugs 24 and tabs 25 between the respective inner and outer portions of the end wall. The isolation mount 42 consists of a self-expanding grommet 44 actuated by a nut 45 on a molded threaded stud 46 which is inserted through the openings in the lugs and tabs and is expanded as shown in FIG. 9 to support the inner portion 22 and provide vibration isolation.

The operation of the embodiment of FIGS. 1-9 is largely self-evident from the foregoing description. The mounting flanges 30 are thus formed integrally with one of the end walls, in this case with an inner portion 22 of the end wall 15 in a blanking and forming operation, thus eliminating the need for a separate motor mount. The flanges are formed in a channel-shaped configuration as shown in FIGS. 5 and 6 for greater strength. The motor 16 may then be attached by the strap 38 as shown in FIG. 2, and the attached blower wheel motor may be inserted in place through the opening defined by the blanked-out inner portion 22 of the end wall 15. The inner portion 22 is then rotated to align the lugs and tabs, and an isolation grommet 42 is inserted and tightened down as shown in FIG. 9.

FIGS. and 11 illustrate a slightly modified form of the invention in which the end wall A is one piece and in which the fingers 30 are formed by suitable metal forming operations directly in the end wall 15A. In this case, the exit region A of the blower is made sufficiently large to permit the insertion of the blower wheel 18 directly through the opening 20A. An inner removable cut-off wall 50 may be employed to restrict the area of the opening 20A. In the event that the motor support fingers 30 interfere with the insertion of the wheel 18 through the opening 20A, the opposite scroll wall may be made removable, or the venturi inlet portion thereof may be removable to permit insertion of the wheel, as described in connection with the em bodiment of FIGS. 11-15 below. Further, this embodiment shows the employment of an encircled elastomeric sleeve 52 surrounding the motor and in underlying relation to the fingers 30 and to the strap 38 providing for isolation of the motor 16 from the housing.

A still further embodiment of the invention is shown in FIGS. 12-15. In this embodiment, the end wall is formed with three arcuately-spaced and inwardlyextending fingers 62 which perform essentially the function as the fingers 30 of the preceding embodiments. Fingers 62 are blanked as shown in FIG. 13 with slightly wider base portions 63 and relatively narrow necks 64. In the blanking and forming steps, the fingers 62 are provided with a configuration as shown in FIG. 14, with the portion 63 extending generally axially of the motor 16 and providing means for threadably supporting a pair of isolation mounting lugs 65, as shown in FIG. 15. Lugs 65 are attached by threaded fasteners 67 which extend up through the bottom of the encircling band 70. The band 70 is received about the motor and in this embodiment, the band 70 is terminated with angularly related flanges 72 which receive fastening bolts 73. By placing the flanges 72 at an angle to the axis of the motor, easy access is permitted for tightening the bolts 73.

The embodiment of FIGS. 12-15 illustrate a still further arrangement for inserting the blower wheel into the interior of the housing. In this case, the opposite blower scroll wall 75 is formed with a removable venturi inlet 76, the latter being removable to permit axial insertion of the motor and the wheel 18 into the interior of the housing.

While three

fingers

30 or 62 have been shown, the invention is not limited to the use of precisely this number of motor attaching fingers. Obviously, in some installations two such fingers might be sufficient and in others four or more may be used. Also, while the scroll end wall is shown as being formed with a venturi inlet opening arcuately between the fingers leading to the interior of the blower wheel, it is to be understood that this may be omitted and that the inlet may be exclusively formed in the opposite wall. Further, the teachings of this invention may be used for mounting motors in tangential blowers or in cross-flow blowers. Also, while the embodiments shown include venturi inlets in each end wall (double inlet blowers), it is within the scope of the invention to use a single inlet blower in which case the integral motor support fingers will be associated with the inlet wall.

While the forms of apparatus herein described constitute preferred embodiments of the invention, it is to be understood that the invention is not limited to these precise forms of apparatus, and that changes may be made therein without departing from the scope of the invention.

What is claimed is:

1. In a direct driven blower of the double inlet type in which a blower wheel is directly mounted on the shaft of the drive motor in a scroll housing, and in which said housing is formed with a pair of opposite end walls, each such wall being formed with an inwardly directed venturi inlet region, the improvement in motor mounting comprising means in one of said walls for supporitng said motor, said motor mounting means including a plurality of radially inwardly extending, arcuately spaced-apart fingers forming a unitary part of said one end wall with the venturi region thereof being formed in the arcuate space between said fingers, and means removably supporting said motor on said fingers with said fingers providing the exclusive support for said motor.

2. The blower of claim 1 in which said one end wall comprises a metal stamping.

3. The blower of claim 2 in which there are three said fingers arcuately spaced from each other by approximatlely 120.

4. The blower of claim 1 further comprising elastomeric isolation means between said fingers and said motor.

5. The blower of claim 1 in which said one end wall is formed in two parts comprising an inner part including said fingers and defining said axial opening and an annular outer part, and elastomeric isolation means joining said inner part to said outer part.

means of said housing defining a removable cut-ofi wall to restrict the area of said exit region.

8. The blower of claim 1 in which said fingers have inner ends which extend axially inwardly into the interior of said housing and have inside surfaces which define a motor-receiving opening which is slightly greater in diameter than the outside diameter of the motor.

9. A direct drive blower comprising a scroll housing adapted to receive a blower wheel therein, means on said housing defining an end wall having an inwardly directed venturi inlet therein, means unitary with said end wall forming a plurality of drive motor support flanges, said flanges having inner ends defining a motor-receiving opening substantially centrally on said wall and proportional to overly the periphery of a blower wheel drive motor, and means associated with said inner ends for supporting such motor on said flanges in said opening.

10. The blower of claim 9 further including vibration isolation means between said flange inner ends and said motor.

11. The blower of claim 9 in which said end wall has means defining a plurality of peripherally spaced mounting lugs, means on said housing defining a corresponding plurality of mounting tabs in alignment with said lugs, and vibration isolation means positioned between said tabs and lugs.

Claims

2. The blower of claim 1 in which said one end wall comprises a metal stamping.

3. The blower of claim 2 in which there are three said fingers arcuately spaced from each other by approximatlely 120*.

6. The blower of claim 1 in which the other of said end walls is removable to provide access for the insertion of said blower wheel in said housing.

7. The blower of claim 1 in which said housing is formed with an exiT region of a size sufficient to provide for the insertion of the blower wheel therethrough, and means of said housing defining a removable cut-off wall to restrict the area of said exit region.