US3390832A

US3390832A - Heavy motor mounting for direct blower assembly

Info

Publication number: US3390832A
Application number: US626247A
Authority: US
Inventors: Donald M Mullings; Howard M Nash
Original assignee: General Electric Co
Current assignee: Trane US Inc
Priority date: 1967-03-27
Filing date: 1967-03-27
Publication date: 1968-07-02
Anticipated expiration: 1985-07-02

Description

y 1968 D. M. MULLINGS ET AL 3,390,832

HEAVY MOTOR MOUNTING FOR DIRECT BLOWER ASSEMBLY Filed March 27, 1967 MN H H N T A NLM 2 Eu o W T [M M ow T United States Patent 3,390,832 HEAVY MOTOR MOUNTING FOR DIRECT BLDWER ASSEMBLY Donald M. Mullings, Yardley, and Howard M. Nash,

Morrisville, Pa., assignors to General Electric Company, a corporation of New York Filed Mar. 27, 1967, Ser. No. 626,247 4 Claims. (Cl. 230-235) ABSTRACT OF THE DISCLGSURE A blower assembly having a hollow housing with at least one air inlet opening in an end wall of the housing. A blower wheel is positioned in the housing, and a motor is interposed in the air inlet opening and joined with the blower wheel for driving the same. The use of a relatively large horsepower motor-blower unit with direct drive is accomplished by utilizing V-shaped suspension brackets which provide maximum stiffness to the motor mounting system while adding little resistance to the air flow.

Cross-reference to related patent This invention is an improved modification of the invention taught in the Donald M. Mullings Patent No. 3,159,108 entitled Mounting Bracket For Blower Assembly which issued on Dec. 1, 1964 and is assigned to the General Electric Company, the assignee of the present invention.

Background of the invention Air moving apparatus of the motor-blower type which incorporates a squirrel cage blower wheel within a scroll housing is in widespread usage, particularly in the heating, ventilating and air conditioning arts. One preferred type of such apparatus includes a blower housing that has an air inlet opening at each end and a blower wheel located within the housing and supported on the drive shaft of an electric motor that is positioned in one of the air inlet openings of the housing. A mounting spider usually surrounds the motor and is fixed thereto.

A blower wheel above about ten inches in diameter with air moving capacities of 2000 c.f.m. and above requires about a three-quarter horsepower motor with a larger and heavier motor frame and this creates problems as to how to suspend the motor in the center of the air inlet opening with maximum rigidity while having a minimum restriction of the airflow.

The principal object of the present invention is to provide an improved suspension means for the motor of a motor-blower unit which will resist twisting actions when the unit is subjected to rough handling during crosscountry shipment by truck or rail.

A further object of the present invention is to Provide an improved suspension means of the class described which will have maximum stifiness while not detracting from the airflow characteristics of the blower unit.

A further object of the present invention is to provide a suspension means of the class described which not only improves the stability of the motor mounting means and provides a minimum restriction of airflow but in fact enhances the airflow characteristics by acting as spoilers to any vortex action that sometimes occurs at the entrance of the air inlet opening.

Summary of the invention The present invention, in accordance with one form thereof, relates to a motor-blower unit having a hollow housing with a blower wheel positioned therein to be in alignment with an air inlet opening in one wall of 3,39%,832 Patented July 2, 1968 the housing. A motor is interposed within the inlet opening and it has a drive shaft that is connected to the blower wheel and forms a support means thereof. A mounting spider surrounds the motor, while a suspension means is connected between the mounting spider and the adjacent wall of the blower housing. Such suspension means comprises a series of V-shaped brackets radially spaced around the spider, where the apex of each V is fastened to the spider and the wide end of the V is fastened to the adjacent end wall of the housing.

Brief description of the drawing Our invention will be better understood from the following description taken in conjunction with the accompanying drawing and its scope will be pointed out in the appended claims.

FIGURE 1 is an end elevation view of a motorblower unit assembly incorporating the improved suspension brackets embodying the present invention for supporting the motor-blower unit from the blower housmg.

FIGURE 2 is a combination cross-sectional elevational and plan view taken on the right angular line 22 of FIGURE 1 to best show the nature of the suspension brackets between the mounting spider of the motor and the blower housing, all with relation to the blower wheel.

FIGURE 3 is a fragmentary exploded view on an enlarged scale showing the configuration of a V-shaped suspension bracket and its relationship to a supporting arm of the motor spider.

Description of the preferred embodiment Turning to consideration of the drawing and in particular to FIGURES l and 2 there is shown a motorblower unit assembly 10. This assembly comprises three main elements; namely, a hollow housing 15 encompassing a blower wheel 16 that is supported and driven by a motor 17. The blower housing 15 is of generally scroll shape having a pair of

parallel end walls

19 and 20 which are each shown with an air inlet opening 21 and 22, respectively. The housing 15 also has a curved side wall 27 joining the two end walls 1? and 26 and having a scroll configuration. Lastly, the housing has a tangential discharge duct 24-. Integral with the duct 24 are a pair of supporting angle irons 18. The assembly 10 is shown as being suspended from a supporting wall 11 by means of hanger bolts 12 that are furnished with resilient bushings 13 for isolating the vibrations of the motor-blower unit from the supporting structure. Such a supporting wall 11 could be one wall of a heat exchanger of a warm air furnace, as one example of an application of the motorblower unit assembly of the present invention.

The blower wheel 16 is illustrated as a double inlet blower wheel having a plurality of longitudinally extending peripheral vanes 29 and a central transverse partition 30 that divides the blower wheel into a pair of

single inlet wheels

31 and 32. The drive motor 17 is interposed within the air inlet opening 21 and it thus creates an annular inlet opening 34 surrounding the motor as is best seen in FIGURE 1. The motor 17 has a shaft 36 that is supported in

opposite motor bearings

37 and 38. The innermost end of the motor shaft 36 is elongated to extend through an opening in the central partition 30 of the blower wheel. The blower wheel is fastened to the shaft by means of a hub 40 that is formed integral with the partition 30. A set screw 41 is threaded into the side of the hub 40 for engagement with a flat side (not shown) of the end of the motor shaft 36, as is conventional in this art. Notice that one end of the motor 17 protrudes outwardly of the blower housing as is best seen in FIGURE 2.

It is necessary to provide the motor 17 with a rigid mounting so that the motor is centered in the air inlet opening 21. The motor is equipped with a mounting spider 43 which comprises a pair of spaced end cups or

mounts

44 and 45 which fit onto the motor end shields or

frames

37 and 38, respectively. These end mounts are connected together by a series of radially spaced longitudinally extending supporting arms 47. Each arm cornprises a pair of L-shaped bracket members 49 of generally channel-shaped transverse section where each is made integral with one of the

end mounts

44 and 45 and has a leg portion which extends longitudinally of the motor housing toward the corresponding L-shaped bracket. These Lshaped brackets are connected together by a heavy bridging member 50 also of channel-shaped cross-section.

This bridging member is provided with suitable openings 51 as are the L-shaped brackets 49 for receiving sheet metal fastening screws 52 that hold the bridging member 50 integral with the brackets 49. The bridging member may be provided with additional openings 51 along the length thereof so that the L-shaped brackets 49 may be adjustably mounted to accommodate varying lengths of motor housings.

Some means must be provided for joining the motor spider 43 to the blower housing 15. Such a suspension means is in the form of a V-shaped bracket 53 for each supporting arm 47 as is best seen in FIGURE 3. This bracket, in its preferred embodiment, is formed of sheet metal that has a flattened apex 55 and a pair of wings 56 which diverge to form a wide end that is adapted to be fastened to the adjacent end wall 19 of the housing 15. Notice that the flattened apex 55 is provided with suitable openings 57 which coincide with some of the openings 51 in the bridging member 50 so that the same fastening screws 52 may be used for attaching the V-shaped bracket 53 to the mounting spider as assembles the bridging member 50 to the related L-shaped bracket 49. Each tip of the wide end of the V-shaped bracket 53 is formed with a right angular tab 59 which is adapted to bear fiush against the end wall 19. Each tab 59 has a hole 60 for receiving a fastening screw 61 or the like that attaches the bracket to the blower housing.

Notice in FIGURE 1 that the V-shaped bracket 53 is turned with its flattened apex 55 overlying the supporting arm 47 so as to minimize the restriction or reduction of air flow. Moreover in FIGURE 3, the V-shaped bracket 53 is shown as being an elongated or widened member especially in the narrow end of the flattened apex 55 so as to provide a sufficient wheelbase in the longitudinal direction for the connection of the bracket 53 to the supporting arm 47. The tabs 59 at the wide end of the V- shaped bracket also give sufiicient wheelbase in the transverse direction for the connection of the bracket 53 to the end wall 19 of the blower housing 15.

Such a rigid suspension means in the form of the V- shaped brackets 53 is of primary value when the motor 17 and blower wheel 16 are of large size and weight and the motor-blower unit is subjected to violent shocks during transit from the factory to the ultimate consumer.

Another unexpected result from adopting this design has been the enhanced air flow characteristics that are apparently due to the thin fin shape of the V-shaped brackets 53 that act as spoilers to any vortex action that sometimes occurs at the air inlet opening. The fins tend to direct the air into the vanes 29 of the blower wheel 16 so that the wheel handles the air more efficiently, similar to the effect of stator blades in a turbine, except that the flow direction is opposite.

Modifications of this invention will occur to those 4 skilled in this art therefore it is to be understood that this invention is not limited to the particular embodiments disclosed but that it is intended to cover all modifications which are within the true spirit and scope of the invention as claimed.

What we claim as new and desire to secure by Letters Patent of the United States is:

1. A motor-blower unit assembly comprising a hollow housing with generally parallel end walls, an air inlet opening in at least one end wall, a blower wheel positioned within the housing in alignment with the air inlet opening, a motor interposed within the air inlet opening, said motor having a drive shaft connected to the blower wheel, and a mounting spider surrounding said motor and fixed thereto, said spider comprising a pair of spaced end mounts secured to said motor and a series of radially spaced longitudinally extending supporting arms joining the end mounts, and suspension means for supporting and spacing the supporting arms relative to the air inlet opening, said suspension means comprising a thin V-shaped metal bracket for each of the supporting arms, each V- bracket having a pair of diverging wings with a flattened apex and fastening means for connecting the apex to the supporting arm, the wings of the V-bracket each having an angular tab at the outer end thereof, and spaced fastening means for attaching the tabs to the adjacent end wall of the housing.

2. A motor-blower unit assembly as recited in claim 1 wherein each wing is wider at the apex end and tapered down at the outer tip, wherein there is a spaced pair of fastening means for connecting each bracket apex to the related supporting arm.

3. In a motor-blower unit assembly comprising a hollow scroll-shaped housing having generally parallel end walls, an air inlet opening in each end wall, a double inletblower wheel positioned within the housing in alignment with the air inlet openings, a motor positioned within one of the said inlet openings, said motor having a shaft connected to the blower wheel and forming the support means thereof, a mounting spider for said motor comprising a pair of spaced end mounts secured to said motor, and a series of radially spaced supporting arms joining the end mounts; the invention comprising means for suspending the motor from the adjacent end wall of the housing, said suspension means comprising a V-shaped sheet metal mounting bracket with diverging wings for each supporting arm, and fastening means attaching the apex of the V bracket to the supporting arm along a portion of the length thereof, and fastening means for attaching the tips of the wings of the V bracket to the ad jacent end wall of the housing.

4. In a motor-blower unit assembly as recited in claim 3 wherein each wing is wider at the apex end and tapered down at the outer tip, the tip of each wing also has an angular tab for receiving the said fastening means that cooperate with the said end wall of the housing.

References Cited UNITED STATES PATENTS 2,686,630 8/1954 Burrowes 230-117 2,711,285 6/1955 Burrowes 230-117 2,798,659 7/1957 Tweedy 230-117 2,923,460 2/1960 Galaba 230-117 2,936,947 5/1960 Staak 230-117 3,127,092 3/1964 Shenberger 230-117 ROBERT M. WALKER, Primary Examiner.