Double motor vacuum

Abstract

A vacuum having a series of motors and fans. As the fans rotate, they draw air into the vacuum. The volume of the air brought into the vacuum is maximized by positioning the fans in series. A plurality of fans is positioned so that outflow from a first fan is the primary inflow into a second fan, and so forth. Together the fans will draw more air than one could alone. By positioning the fans in series, the external diameter of the vacuum does not need to be any larger than it would for a vacuum having a single fan. The fans and motors are contained in a housing having an intake aperture. The intake aperture is preferably separated from the intake opening to the first fan and is preferably slightly smaller than the intake openings to the first fan. This will cause air entering the housing to accelerate.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to vacuum motors in general and in particular to high efficiency high strength vacuum motors.

2. Prior Art

Electric motors are commonly used to drive the fans in vacuums. The more air the fan entrains, the stronger the vacuum will be. Typically, greater suction strength is obtained by providing the vacuums with more powerful motors which are capable of rotating the fans at a higher rate. However, strengthening the vacuum output in this manner creates several problems. First, more powerful motors require more amperage. Where the vacuum is battery operated, these more powerful motors will exhaust the battery more quickly, resulting in a shorter operating life for the vacuum.

Another problem with increasing vacuum strength by simply using a stronger motor is that stronger motors are generally larger than their standard counterparts. Thus, increasing motor strength will generally require the size of the vacuum housing to be increased as well. This can be undesirable, particularly in hand held vacuums. Smaller more compact vacuums are often desired in many of the environments where hand held vacuums are used and stored, such as in automobiles, office work spaces, and the like. Anything that increases the girth of these vacuums is often unwanted.

Fan size may also be increased to increase the strength of the vacuum. However, increasing fan size will increase the load on the motor and require the size of the housing to increase as well. As with increasing motor power, the increased load on the motor will more rapidly deplete battery life when cordless vacuums are employed.

The volume of air moving through the vacuum will be controlled by the fan size and speed of rotation. However, the speed of the air entering the vacuum may also be controlled by the size and shape of the air inlet. The strength of the vacuum may be enhanced by accelerating the air as it enters the vacuum. Accordingly, a vacuum meeting the following objectives is desired.

OBJECTS OF THE INVENTION

It is an object of the invention to provide a vacuum of increased strength.

It another object of the invention to provide a vacuum of increased strength without increasing the girth of the vacuum housing.

It is yet another object of the invention to provide a vacuum of increased strength without increasing the size of the vacuum fan.

It is still another object of the invention to provide a vacuum of increased strength without increasing the size of the vacuum motor.

It is yet another object of the invention to provide a vacuum having an improved air inlet configuration.

SUMMARY OF THE INVENTION

The invention comprises a vacuum having a series of motors. Each motor is equipped with a fan. The motors are configured to drive the fans. As the fans rotate, they will draw air into the vacuum. The flow of air into the vacuum will create the suction used to pick up dirt and other particles. The strength of the vacuum is determined by the volume of the air moving into the vacuum and the speed at which the air is moving.

In the present invention, the volume of air brought into the vacuum is maximized by positioning the motors and their fans in series. A plurality of motors is positioned so that the outflow from a first motor is the sole or primary inflow into a second motor and fan, and so forth. Together the fans will draw more air into the vacuum than one could alone. By positioning the motors and fans in series, the girth or external diameter of the vacuum body does not need to be any larger than it would for a conventional vacuum with a single motor and fan.

In the preferred embodiment, the fans and motors are provided with a housing. The housing prevents the second motor and fan from taking in air from anywhere except the outflow of the first motor and fan. Similarly, it prevents the outflow of air from the first motor and fan from being discharged anywhere except into the second motor and fan. An intake aperture is provide in the housing. In the preferred embodiment, the intake aperture is slightly smaller than the intake openings to the first fan. This will cause the air entering the housing to accelerate, thereby further strengthening the vacuum. The intake aperture to the housing is preferably separated from the intake opening to the first fan.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front perspective view of a preferred embodiment of a housing containing a plurality of motors and fans in series.

FIG. 2 is a rear end view of a preferred embodiment of a housing containing a plurality of motors and fans in a series.

FIG. 3 is a cut-away side view of a preferred embodiment of a housing containing a plurality of motors and fans in series.

FIG. 4 is an front end view of a preferred embodiment of a fan.

FIG. 5 is a rear end view of a preferred embodiment of a motor and fan.

FIG. 6 is an exploded perspective view of a preferred embodiment of a motor and fan with cover and base plate.

FIG. 7 is a partial cut-away front end view of a preferred embodiment of a fan mounted over a base plate.

FIG. 8 is a side view of a preferred embodiment of a vacuum containing a preferred embodiment of a housing containing a plurality of motors and fans in series.

FIG. 8A is a side view of another preferred embodiment of a vacuum containing another preferred embodiment of a housing containing a plurality of motors and fans in series.

FIG. 9 is an exploded perspective view of one preferred embodiment of a housing containing a plurality of motors and fans in series.

DETAILED DESCRIPTION OF THE BEST MODE OF THE INVENTION

A vacuum 1 having a series of motors 2 is disclosed. Each motor 2 has a motor shaft 2A which drives a fan 3. Fans 3 may take any conventional shape; however, the preferred embodiment employs a radial fan configuration. A radial fan 4 has an upper surface 5 and a lower surface 6. Upper surface 5 contains an intake opening 7. Intake opening 7 is preferably centrally positioned in upper surface 5. A plurality of vanes 8 are positioned between upper surface 5 and lower surface 6. Vanes 8 preferably extend from intake opening 7 to the outside edge 9 of fan 3. Vanes 8 are preferably curved. When fan 3 rotates, air will be drawn into intake opening 7 and pushed out of radial fan 4 at outside edge 9.

There is preferably a base plate 10 between motor 2 and fan 3. Base plate 10 is preferably wider than fan 3. Base plate 10 is also preferably provided with a plurality of vents 11 between the outside edge 9 of fan 3 and periphery of base plate 10. Vents 11 will allow air entrained by fan 3 to pass through base plate 10. Vents 11 may be provided with fluting 12 to allow air entrained by fan 3 to pass through base plate 10 at an angle. This will allow air to pass through base plate 10 with less turbulence than would be the case if air were required to pass through base plate 10 at a right angle thereto.

A fan cover 13 is preferably provided over fan 3. Fan cover 13 will mount to base plate 10 and will contain an intake opening 7A in line with intake opening 7. Fan cover 13 will allow air to enter fan 3 via intake opening 7 but will ensure that substantially all of the air exiting fan 3 will pass through vents 1 1 in base plate 10.

A plurality of motors 2 and fans 3 are preferably placed in a series 14, one in line with the other. Although in the preferred embodiment series 14 only contains two motors 2 and two fans 3, it will be appreciated that a series 14 comprising any number of motors 2 and fans 3 may be used.

Series 14 is preferably contained within a housing 15. Housing 15 is preferably made of plastic, metal or other suitable airtight material. One or more motors 2, fans 3, base plates 10, and fan covers 13 will be positioned within housing 15. Housing 15 will have an inside diameter that is coextensive with the periphery of each base plate 10. The connection between housing 15 and each base plate 10 will be substantially air tight, such that air will only be able to pass from one side of base plate 10 to the other by passing through vents 1 1.

Housing 15 will have an intake end 16 and a discharge end 17. Fans 3 will be oriented in housing 15 so that intake openings 7 of fans 3 will face intake end 16 of housing 15. Discharge end 17 will include a discharge vent 31 and will preferably comprise the base plate 10 of one of the motor 2/fan 3 combinations, such that one of the motors 2 will actually be positioned outside of housing 15. In the preferred embodiment, vents 11 in the base plate 10 at discharge end 17 will serve as discharge vent 31.

In one preferred embodiment, intake end 16 will contain an intake aperture 18. Intake aperture 18 is preferably slightly smaller than intake openings 7 and 7A. Intake aperture 18 is preferably separated from intake opening 7 of the leading fan 3 in housing 15, most preferably by a distance about equal to or greater than the diameter of base plate 10.

In another preferred embodiment, intake end 16 of housing 15 will be formed by cover 13 and/or base plate 10 of the leading motor 2/fan 3 combination as illustrated in FIGS. 8A and 9.

Housing 15 further comprises substantially airtight sidewalls 19 that extend from intake end 16 to discharge end 17. In the preferred embodiment, sidewalls 19 will taper outward smoothly from intake aperture 18 to where housing 15 meets base plate 10 of the leading fan 3 in housing 15. In one embodiment, illustrated in FIGS. 1, 3, and 8, the volume within housing 15 will preferably increase when viewed from intake aperture 18 to base plate 10, herein the expanded zone 26. In another preferred embodiment, the volume within housing 15 will remain substantially constant.

Although sidewalls 19 are preferably airtight, passages may be provided in sidewalls 19 to accommodate electrical lines leading to motors 3 contained within housing 15. These passages will preferably be substantially sealed with silicone or the like in order to render them substantially airtight after the necessary wires are in place.

Positioning the motors 2 and fans 3 of series 14 in housing 15 will allow the power of each fan 3 exerted on the airstream to be compounded. Air flowing into the leading fan 3 in series 14 will pass through a base plate 10 which will effectively separate one fan 3 from the next. The air exiting the leading base plate 10 will be the only inflow air available to the next fan 3 in series 14. Acting together, two fans 3 in series 14 are expected to be able to move roughly twice the amount of air as any one of them acting alone. Similar results are expected when additional fans 3 are included in the series.

In the preferred embodiment, housing 15 containing series 14 is positioned in a vacuum 1 having a body 20. Vacuum body 20 will include a power source 21 operatively connected to motors 2 in series 14 and preferably a switch 22 for activating and deactivating the connection between power source 21 and motors 2. Power source 21 may be batteries, a connection to a wall or automotive outlet, or any other conventional power source. Vacuum body 20 will also include a nozzle 23 configured to allow an airstream into vacuum 1. Vacuum body 20 will also include a filter 24 for separating dirt, dust, and the like from the airstream entering vacuum 1. Housing 15 will be positioned within vacuum body 20 to pull the airstream from the surroundings through nozzle 23 and into vacuum 1 so that the airstream passes through filter 24. Once the debris in the airstream has been removed by filter 24, the airstream will pass through housing 15 and exit vacuum 1 via an exhaust vent 25.

By placing fans 3 in series 14, additional vacuum strength is obtained without increasing the girth—the external diameter—of vacuum 1. Because motors 2, fans 3, and especially base plates 10 are positioned in vertical alignment with each other (i.e., fans 3 and base plates 10 are in substantially parallel planes and fans 3 are on substantially the same axis), series 14 will not have any greater girth than any one motor 2, fan 3, and base plate 10 alone. Thus, vacuum 1 will not have to be any wider to accommodate series 14 than it would have had to be to accommodate a single less powerful fan 3 and motor 2.

As noted above, in one embodiment intake aperture 18 is preferably narrower than intake opening 7. Forcing the airstream through a smaller opening should require the airstream to accelerate. Faster flow of the airstream will also increase the strength of vacuum 1. Separating intake aperture 18 from intake opening 7 and providing the expanded zone 26 between intake aperture 18 and intake openings 7, 7A should help minimize the effect of any turbulence created in the airstream by the passage through intake aperture 18.

Although the invention has been described in terms of its preferred embodiment, other embodiments will be apparent to those of skill in the art from a review of the foregoing. Those embodiments as well as the preferred embodiments are intended to be encompassed by the scope and spirit of the following claims.

Claims

1. A vacuum comprising

a body having a nozzle configured to allow air into said body and an exhaust vent configured to allow air to exit said body;

a filter configured to separate dust and debris from air passing through said body;

a power source

a housing containing a leading fan and at least one following fan, each said fan being operatively connected to and rotated by a motor in operative connection with said power source, each said fan configured to intake and discharge air, wherein said leading fan is positioned to intake air external to said housing and wherein said following fan is positioned to intake the air discharged from said leading fan, and wherein said leading fan and said following fan are aligned with each other in said housing so that said fans rotate in substantially parallel planes and so that said fans rotate on substantially the same axis; and

wherein said housing and said fans are positioned in said body to draw air into said nozzle, through said filter, through said housing and out said exhaust vent.

2. A vacuum according to claim 1 wherein at least one of said fans is a radial fan.

3. A vacuum according to claim 2 wherein at least one of said fans further comprises a plurality of curved vanes.

4. A vacuum according to claim 2 wherein at least one of said fans is enclosed within a base plate and a fan cover.

5. A vacuum according to claim 4 wherein said base plate comprises a vent and wherein said fan cover comprises a centrally located intake opening, whereby the intake and discharge of air from said at least one of said fans may be controlled.

6. A vacuum according to claim 1 wherein said housing further comprises and intake end, a discharge end, and substantially airtight sidewalls extending therebetween.

7. A vacuum according to claim 6 wherein said intake end further comprises an intake aperture and wherein said discharge end further comprises a discharge vent.

8. A vacuum according to claim 7 further comprising a base plate positioned between said leading fan and said at least one following fan, said base plate having a vent providing air passage through said base plate and wherein said base plate and said sidewalls are in substantially air tight engagement whereby air may not pass from said leading fan to said at least one following fan via said housing without passing through said vent in said base plate.

9. A vacuum according to claim 8 wherein said leading fan is separated from said intake aperture of said housing by a distance that is at least about the diameter of said leading fan.

10. A vacuum according to claim 8 wherein said leading fan is provided with a fan cover having a centrally positioned intake opening, said cover and intake opening positioned and configured to substantially prevent the intake of air by said leading fan except through said intake opening.

11. A vacuum according to claim 10 wherein said intake opening of said cover is separated from said intake aperture of said housing by a distance that is at least about the diameter of said leading fan.

12. A vacuum according to claim 11 wherein said intake aperture of said housing is smaller in area than said intake opening of said cover.

13. A vacuum according to claim 12 wherein said sidewalls taper outward from said intake aperture to where said sidewalls meet said base plate.

14. A vacuum according to claim 11 wherein said sidewalls taper outward from said intake aperture to where said sidewalls meet said base plate.