WO2004010838A2

WO2004010838A2 - Portable hand-held battery-operated dust blower

Info

Publication number: WO2004010838A2
Application number: PCT/US2003/023399
Authority: WO
Inventors: Anthony J. Lammers; John R. Nottingham; John W. Spirk; Jeffrey Scott Plantz; Patrick W. Brown
Original assignee: Innodesk Business Tools, Inc.
Priority date: 2002-07-26
Filing date: 2003-07-25
Publication date: 2004-02-05
Also published as: AU2003254197A8; AU2003254197A1; US20050210624A1; WO2004010838A3

Abstract

A hand-held, battery-operated air blower is disclosed having a housing with a handle portion, a discharge end, an air inlet and a discharge aperture. A battery compartment is provided in the handle portion of the housing to contain one or more batteries. The battery compartment is electrically connected to a motor disposed within the housing between the battery compartment and the discharge aperture, transverse to the longitudinal axis of the housing. A centrifugal fan is mounted on the motor and positioned within the housing adjacent the air inlet in such a manner that operation of the fan draws air in through the air inlet and forces it out from the fan toward the discharge aperture then out through the discharge aperture. An actuator is provided for switching the flow of electricity from the batteries to turn the motor on and off.

Description

TITLE OF INVENTION

Portable Hand-Held Battery-Operated Dust Blower BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to hand-held air blowers, and more particularly, to a hand-held, battery- operated air blower that achieves superior airflow through use of a centrifugal fan mounted transversely toward the front of the blower. 2. Description of the Prior Art Air blowers in various forms are available for numerous uses, such as drying hair or other objects, blowing fallen leaves, and blowing air into a fireplace or charcoal grill to accelerate combustion. Another application for air blowers is removal of dust from hard-to- reach places such as between the keys of typewriters and computer keyboards and from fragile or irregularly shaped objects, such as dried flower arrangements and artificial plants. For this application, the blower will be most useful if it is small enough to be held in one hand and powered by one or more batteries in order to avoid the need for a power cord and electrical outlet.

In order to extend battery life in such an application and avoid the need for an excessively large power supply, it is important that the blower mechanism be as efficient as possible at converting electrical energy to air flow. While several types of hand-held, battery- operated blowers are presently available, they typically employ either an axial type fan or a centrifugal fan mounted coaxially with the longitudinal axis of the blower housing.

For example, U.S. Patent No. 4,734,017 discloses a blower employing an axial type fan, similar to a propeller, which draws air into the fan inlet and expels it axially. Greater air pressure can typically be achieved through use of a centrifugal fan, such as that employed in the blower disclosed by U.S. Patent No. 6,092,260, which draws air into the inlet and forces it out of the fan at a right angle radially. However, the blower of Patent No. ^'6 ,0927260^~Has ^"the^" centrifugal^_fan mounted^{^}coaxially -in- the blower4ιousing — causing-the- air- stream to be directed against the inner walls of the blower housing rather than directly toward the discharge aperture. This position may increase turbulence within the housing, diminishing the efficiency of blower operation. This problem may be exacerbated by placement of the fan toward the rear of the blower housing in the device of Patent No.

6,092,260, because the fan must force air past the blower motor and batteries before it reaches the discharge aperture.

Thus, there remains a need for a hand-held, battery-operated blower that takes full advantage of the greater efficiency of a centrifugal fan by having the centrifugal fan mounted toward the front of the blower housing transverse to the longitudinal axis of the blower housing so that air flow generated by the fan reaches the discharge aperture with minimal obstruction.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a hand-held, battery- operated blower that efficiently produces a stream of air through a discharge aperture from a transverse-mounted centrifugal fan. Specifically, the present invention provides a hand- held, battery-operated blower comprising: a housing having a handle portion and a discharge end with an air inlet on one side of the discharge end and a discharge aperture at the tip of the discharge end; a compartment within the handle portion for containing batteries; a motor disposed within the housing between the battery compartment and the discharge aperture transverse to the longitudinal axis of the housing, said motor being electrically connected to the battery compartment; a centrifugal fan mounted on the motor within the housing and adjacent to the air inlet; and means for controlling the supply of electricity from the power source to the motor in order to turn the blower on and off. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view of the dust blower; Fig. 2 is a cross-sectional view taken through lines 2-2 in Fig. 1;

Fig. 2 is a cross-sectional view taken through the lines 3-3 in Fig. 2; Fig. 4 is a fragmentary plan view of the underside of the dust blower showing the internal loop attachment; and

_Eig..5_is. an.elevatiojιa view_of he_ right j3ide.;_ Fig. 6. is an elevational view of the left side;

Fig. 7 is a bottom plan view; Fig. 8 is a top plan view; Fig. 9 is a rear elevational view; Fig. 10 is a front elevational view;

Fig. 11 is a sectional view taken along the lines 11-11 in Fig. 4; and Fig. 12 is a sectional view taken along the lines 12-12 in Fig. 4.

DETAILED DESCRIPTION OF THE INVENTION

Using the above-identified figures, the invention will now be described with respect to various preferred embodiments. Although many specificities will be mentioned, it must be emphasized that the scope of the invention is not to be taken to be that of only the preferred embodiments, bμt should be construed in accordance with the claims appended below.

Referring to Figs. 1-5, Fig. 1 shows a handheld blower 10 according to the present invention. The blower includes a housing 12 having a left side 14, a right side 16, a handle portion 20, and a discharge end 22. The housing 12 may be manufactured of any appropriate material, preferably a lightweight, durable material such as high-impact plastic. The discharge end 22 tapers to form a discharge aperture 24. Aperture 24 is preferably elliptical or oblong, to prevent turbulence from building at the point of discharge, while at the same time allowing for an increase of discharge air pressure. The right side 16 of the housing 12 includes an air inlet 26 disposed on the discharge end 22. A grille 27 across the air inlet 26 provides a cage-style cover for a fan blade 36 and prevents interference with the rotation of the blade 36 as well as infiltration of debris. A screen (not shown) may be optionally attached behind the grille 27 for additional air filtration. In the preferred embodiment, grille 27 is comprised of a plurality of curved segments 27a separated by air gaps 25. A second grille may be included on the opposing side for symmetry in appearance. The second grille may also provide cooling air for the motor, and optionally, a supplemental fan/ air inlet, or there may be a solid cover placed behind the second grille to prevent air infiltration from that side of the blower.

A switch 40 is disposed on top of the housing 12 for turning the blower 10 on and off..--Switch_-^40 rovides_^acmatmg-meansJ^'or-elec calIyxoupling,a miniature-D.C-motor-.28- with a DC power source. In the preferred embodiment, switch 40 is a slidable, spring- maintained momentary contact type of switch, although any number of low-voltage switches may be suitable. Raised collar 46 surrounds the switch 40 to prevent accidental actuation of the switch, such as may otherwise occur when the device is laid on a surface with the switch 40 facing down. The handle portion 20 may include a loop of string or rope 29 at the end for hanging the blower 10 from a hook. In alternative embodiments, not shown, the string could be replaced by an integral loop forming part of the housing itself or by a metal or plastic ring or similar device affixed to the housing.

A motor 28 is coupled to a centrifugal fan 34 by means of a shaft 30. Motor 28 and fan 34 are disposed within the housing 12 adjacent to air inlet 26. Centrifugal fan has curved fan blades 36 extending radially from the center of the fan to the periphery of the fan. Referring to Fig. 2, fan blades 36 are mounted on a generally flat circular disc.

Blades 36 are configured in such a manner that when the motor 28 drives the centrifugal fan 34, air is drawn in through the air inlet 26 and forced out through the discharge aperture 24. The proximity of the fan 34 to the nozzle or discharge aperture 24 ensures a direct flow of air and maximum pressure at the point of discharge of air at the aperture 24. The positioning also eliminates air turbulence due to obstruction caused by parts in the flow path, since the component parts such as the motor 28 and batteries are located outside of the airflow path. Further, as discussed above, the elliptical geometry of the aperture 24 reduces turbulence, allowing a greater flow rate and pressure at the point of discharge.

While the motor 28 has shaft 30 projecting from one end, in alternate embodiments, the motor may be positioned midway between the left and right sides of the housing, with a shaft extending from both ends. Centrifugal fans may be thus mounted on either end or on both ends of the motor. Grille 27, having air inlets, may be provided on both sides of the housing adjacent to the fans, and the blades of the fans configured so that each centrifugal fan draws air through its respective inlet and expels it toward the discharge aperture. In yet another alternative embodiment, not shown, only one centrifugal fan is provided, but the housing has a second grille (not shown) on the side adjacent to the motor for air-cooling the motor.

Fig. 3 shows a battery compartment 38 disposed within the handle portion 20 of the .housmg 2._TIιe_battery_compartment-38JS-electrically_connec disposed within the housing 12 adjacent the battery compartment 38 and between the battery compartment 38 and the discharge aperture 24 such that the shaft 30 of the motor 28 is transverse to a longitudinal axis 32 of the housing 12. The battery compartment 38 is configured to hold batteries of an appropriate size and in an appropriate number to power the motor 28. The electrical connection (not shown) between the battery compartment 38 and the motor 28 includes switch 40 (see Fig. 1) provided on the outside of the housing 12 for turning the blower 10 on and off. In the disclosed embodiment, the battery compartment is configured to hold four AA batteries 42. In an alternative embodiment, not shown, the battery compartment may be configured to hold a rechargeable battery, and a connection provided in the handle portion of the housing to connect a charging device for recharging the battery from household current. Also, a power cord connection may optionally be provided in the handle portion of the housing in addition to the battery compartment so that an AC to DC adaptor can be plugged into the blower for operation on a standard 110-volt outlet.

Fig. 4 shows a removable battery compartment door 44 provided in the housing 12 to provide access to the battery compartment 38 for installing and changing batteries.

The momentary-contact switch 40 on the handle also provides a means for test operation that may be used in the original packaging. The momentary operation of the switch permits the user to operate the device 10 while still wrapped in protective packaging. A transparent thin plastic barrier (not shown) is molded around a portion of the device 10 and adhesively or mechanically attached to a backing sheet of cardboard (also not shown), with the device secured between the plastic barrier and the cardboard. The plastic is pliable so that the pushbutton on the switch may be depressed to turn on the device while on the store shelf. The switch is returned to the off position when released, thereby avoiding unintended drainage of the batteries in the packages. This feature advantageously invites people to test-operate the device.

Referring to Fig. 11, the arrangement of the motor 28 inside housing 12 is shown. Hollow plastic motor mounting bosses 46a, 46b are molded on the inside of housing 12, on the side 16 opposite the inlet 26. A bracket 50 fits over motor 28 and is fastened to mounting bosses 46a, 46b, preferably with self-tapping screws or similar fastening means.

Referring to Fig. 12, a sectional view taken through the center of the blower 10 shows batteries 52a, 52b inside the battery compartment 38. Switch 40 is also shown in cross-section.

According to the provisions of the patent statutes, we have explained the principle, preferred construction, and mode of operation of the invention, and have illustrated and described what we now consider to represent its best embodiments. However, it should be understood that within the scope of the appended claims and the foregoing description, the invention may be practiced otherwise than as specifically illustrated and described.

Claims

WHAT IS CLAIMED IS:

1. A hand-held blower comprising:

(a) a housing having a handle portion and a discharge end, wherein the discharge end includes a fan, an air inlet and a discharge aperture; (b) a battery compartment within the handle portion of said housing for holding one or more batteries;

(c) a motor disposed transverse to the longitudinal axis within said housing between said battery compartment and the discharge aperture, wherein said battery compartment is adjacent to and electrically coupled to the motor in order to energize the motor when one or more batteries are installed in said battery compartment;

(d) a centrifugal fan mounted on said motor within said housing and adjacent the air inlet and driven by said motor for directing air from the inlet through the discharge aperture; and (e) switching means to turn said blower on and off.

2. The hand-held blower as set forth in claim 1, wherein said fan also discharges pressurized air directly into said discharge aperture when rotating.

3. The hand-held blower as set forth in claims 1 or 2, wherein said discharge aperture including a tapered nozzle for direction of stream of pressurized air.

4. The hand-held blower as set forth in claim 3, wherein said discharge aperture is elliptical.

5. The hand-held blower as set forth in claims 1, 2, 3 or 4, wherein said air inlet having a grille covering the opening to allow passage of air and for preventing interference with the rotation of the fan.

6. The hand-held blower as set forth in claims 1,2,3,4 or 5, wherein also including one or more of the following: batteries, rechargeable battery, an optional power connector, or an AC power adapter.

7. The hand-held blower as set forth in claims 1, 2, 3, 4, 5, or 6, wherein also including a loop attachment.

8. The hand-held blower as set forth in claim 7, wherein said loop attachment being made from a material selected from one of the following: string, rope, cord, metal ring and plastic ring.

9. The hand-held blower as set forth in claims 1-8 above, wherein said switching means is a momentary contact, spring maintained switch.

10. The hand-held blower as set forth in claims 1-9 above, wherein said switch while in a package may be operated without opening said package, and return to a "normally off position when released so as to prevent drainage of the power source.

11. The hand-held blower as set forth in claims 1-10 above, also including one or more air inlets to provide cooling air to the motor.

12. The hand-held blower as set forth in claims 1-11 above, also including a second motor and fan arrangement to increase the amount of air supplied to the discharge aperture.

13. A hand-held blower comprising : a housing, said housing including a handle portion and a discharge end, wherein the discharge end includes a fan, an air inlet and a discharge aperture; a battery compartment within the handle portion of said housing for holding one or more batteries; _ a motor disposed within said housing between said battery compartment and the discharge aperture, wherein said battery compartment is adjacent to and electrically coupled to the motor in order to energize the motor when one or more batteries are installed in said battery compartment; a centrifugal fan mounted on said motor within said housing and adjacent the air inlet and driven by said motor for directing air from the inlet through the discharge aperture; and a switch for electrically coupling the motor to the battery compartment to turn said blower on and off.

14. The hand-held blower as set forth in claim 13, wherein said fan also discharges pressurized air directly into said discharge aperture when rotating.

15. The hand-held blower as set forth in claims 13 or 14 wherein said discharge aperture including a tapered nozzle for direction of stream of pressurized air.

16. The hand-held blower as set forth in claim 15, wherein said discharge aperture is elliptical.

17. The hand-held blower as set forth in claims 13, 14, 15 or 16, wherein said air inlet having a grille covering the opening to allow passage of air and for preventing interference with the rotation of the fan.

18. The hand-held blower as set forth in claims 13, 14, 15, 16 or 17, wherein also including one or more of the following: batteries, rechargeable battery, an optional power connector, or an AC power adapter.

19. The hand-held blower as set forth in claims 13, 14,15, 16, 17 or 18, wherein also including a loop attachment.

20. The hand-held blower as set forth in claim 19, wherein said loop attachment being made from a material selected from one of the following: string, rope, cord, metal ring and plastic rjng._

21. The hand-held blower as set forth in claims 13, 14, 15, 16, 17, 18, 19 or 20, wherein said switching means is a momentary contact, spring maintained switch.

22. The hand-held blower as set forth in claims 13, wherein said switch while in a package may be operated without opening said package,, and return to a "normally off position when released so as to prevent drainage of the power source.

23. The hand-held blower as set forth in claim 13, also including one or more air inlets to provide cooling air to the motor.

24. The hand-held blower as set forth in claim 13, also including a second motor and fan arrangement to increase the amount of air supplied to the discharge aperture.