Note: Descriptions are shown in the official language in which they were submitted.
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VAC~fT~UM CLEANER WITH TWIN
INDEPE:C~TDENTLY DRIVEN AGITATORS
This application c;laims the benefit of U.S. Provisional Patent
Application Serial No. ~i U/539,467 filed on January 27, 2004.
Technical Field
The present invention relates generally to the vacuum cleaner art
and, more particularly, to a vacuum cleaner incorporating twin agitators
with each agitator drive:» by an internal drive motor.
ac ground of the Inve~p,~
A vacuum clean~;r is an electro-mechanical appliance utilized to
effect the dry removal o E' dust, dirt and other small debris from carpets,
rugs,
fabrics or other surface;r in both domestic and industrial environments. In
order to achieve the desired dirt and dust removal, a rotary agitator is
provided to beat dirt and dust from the nap of the carpet and a pressure drop
or vacuum is used to force air entrained with this dirt and dust into the
nozzle of the vacuum c:l~~aner. The particulate-laden air is then drawn
through a bag-like filter, a dirt cup or a cyclonic separation chamber and
filter combination which traps the dirt and dust, while substantially clean
air
is exhausted by an elecia-ically operated fan that is driven by an on board
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motor. It is this fan and motor arrangement that generates~the drop in air
pressure necessary to prc>vide the desired cleaning action. Thus, the fan and
motor arrangement is co:nmnonly known as the vacuum, or suction generator.
Many advanced, lxigh performance vacuum cleaners incorporate a
dual motor system. In sixch a system, a separate agitator drive motor is
provided in addition to tk~e motor of the suction generator. In most designs
the separate agitator drive motor is mounted on the nozzle assembly
adjacent the agitator. A. gear drive or more commonly a pulley and belt
arrangernent transmits ttm power from the agitator motor drive shaft to the
agitator.
V'Jhile very effective for its intended purpose, the mounting of a
separate agitator drive rc~otor in front of or behind the agitator
necessitates a
significant increase in tlk~c; fore-aft length of the nozzle assembly in order
to
accommodate the motor. This not only increases the overall weight of the
nozzle assembly but also the wheelbase and/or the body overhang beyond
the wheels. All of then; characteristics negatively impact the ease of
manipulation of the vacaxum cleaner in and around furniture and, therefore,
are a detriment.
In contrast, it is ~;~ossible to mount the agitator drive motor above the
agitator. In this situatia:n, no increase in the length of the nozzle
asse~.nbly
and/or the wheelbase th.~~reof is necessary to accommodate the agitator
motor. 'The height of ttia nozzle assembly must, however, be increased
significantly to provide motor clearance. This unacceptably restricts the use
of the vacuum cleaner as the resulting higher profile will not clear many
overhanging obstructions such as bed frames, tables and chair frames.
Accordingly, this is geriera.lly recognized to be an unacceptable solution.
Another possiblt: alternative is the mounting of the separate agitator
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drive motor within the av;;itator itself. Such an arrangement makes use of
what would otherwise b~~ lost space within the agitator. Further, it allows
the agitator motor to be ~~ccommodated without any substantial increase in
the height or length of tt~e nozzle assembly. Thus, the vacuum cleaner may
be more easily manipul:~ted on a shorter wheel base and is of lighter overall
weight. It also includes the desired low profile which allows cleaning
under bed frames, table;, chairs and other such obj ects.
More recently, it ;has been determined that vacuum cleaners
equipped with multiple agitators provide a performance advantage resulting
in enhanced cleaning efl:iciency. The present invention relates to a multi-
agitator vacuum cleaner wherein each agitator is independently driven and
includes its own interna.Fly mounted drive motor. Such a vacuum cleaner
provides maximum cleaczing performance while also limiting the height and
footprint of the nozzle ftssembly. As a consequence, the vacuum cleaner is
easy to maneuver and h~us a relatively low profile so as to allow cleaning
under beds, chairs and the like.
_S;r of the Inventi~~
In accordance w:i th the purposes of the present invention as
described herein, an im~yroved floor cleaning apparatus is provided. That
floor cleaning apparatu;3 comprises a nozzle assembly, a canister assembly
and a suction generator harried on one of the nozzle assembly and the
canister assembly. Additionally, the floor cleaning apparatus includes a
dirt collection vessel al,~o carried on one of the canister assembly and the
nozzle assembly. Still iiarther, a first agitator having a first internal
drive
motor is carried on the nozzle assembly. Additionally, a second agitator
having a second internal drive motor is earned on the nozzle assembly.
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The canister assembly may be pivotally connected to the nozzle
assembly. Further, the dirt collection vessel may take any of various forms
including but not limite~~, to a filter bag, a dirt cup and a cyclonic airflow
chamber. Further, the cleaning apparatus itself may be a device selected
~5 from a group consisting of an upright vacuum cleaner, a canister vacuum
cleaner, a hand-held vac; uum cleaner and an extractor.
Alternatively, the; present invention may be described as a floor care
cleaning apparatus com~yrising a nozzle assembly, a canister assembly, a
suction generator carrie~;l on one of the nozzle assembly or the canister
~0 assembly and a dirt collE>ction vessel carried on one of the nozzle or the
canister assembly. The apparatus further includes a first agitator and first
agitator drive motor and a second agitator and second agitator drive motor.
Thus, the two agitators Fine independently powered.
In accordance w:i~th yet another aspect of the present invention, a
S method is disclosed .for 5roviding an improved floor cleaning apparatus.
The method includes the; steps of equipping the floor cleaning apparatus
with a first agitator and ~~. second agitator and independently driving those
two agitators. The agitt~tors may be driven at different speeds and/or in
different directions.
20 Advantageously;. the floor cleaning apparatus provides enhanced
cleaning performance arid a relatively low profile and compact nozzle
assembly that is easily rnaneuvered over a surface to be cleaned and has the
necessary clearance to lm used under beds, chairs and the like.
In the following description there is shown and described a preferred
r5 embodiment of this inv~;uiti.on, simply by way of illustration of one of
the
modes best suited to carry out the invention. As it will be realized, the
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invention is capable of other different embodiments and its several details
are capable of modifica~.ion in various, obvious aspects all without
departing from the invention. Accordingly, the drawings and descriptions
will be regarded as illustrative in nature and not as restrictive.
5 Brief Description of the_II?raving
The accompanyi~a.k; drawing incorporated in and forming a part. of
the specification, illustr~.tes several aspects of the present invention, and
together with the descri:ytion serves to explain certain principles of the
invention. In the drawuc~g:
Figure 1 is a per,c~ective view of a floor cleaning apparatus of the
present invention, illustCated in the form of an upright vacuum cleaner;
Figure 2 is a tram:verse sectional view of the vacuum cleaner
through the first agitato r ; and
Figure 3 is a det~~iled cross-sectional view of the first agitator and
gear drive showing the ~~,rigagement therebetween.
Reference will n~~~w be made in detail to the present preferred
embodiment of the inveyition, an example of which is illustrated in the
accompanying drawing"
Reference is nov~~ made to Figure 1 showing a floor cleaning
apparatus 10 of the presc;nt invention. As illustrated, that floor cleaning
apparatus 10 takes the fc~r~ra of an upright vacuum cleaner. It should be
appreciated, however, that the floor cleaning apparatus may also take the
form of a canister vacuum cleaner, a hand-held vacuum cleaner or even an
extractor.
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T:he overall basic. design of the floor cleaning apparatus 10 is
generally well known ins the art. In the typical arrangement, the floor
cleaning apparatus 10 irtcludes a housing 14 that comprises the nozzle
assembly 16 and the canister assembly 18. The canister assembly 18 further
includes the handle 20 ~cnd the hand grip 22. The hand grip 22 carries a
control switch 24 for tu:raing the floor cleaning apparatus 10 on and off. Of
course, electrical power i.s supplied to the floor cleaning apparatus 10 from
a standard electrical wa;f l outlet through a cord (not shown). Alternatively,
the floor cleaning apparatus 10 could be powered by an onboard battery.
At the lower por~:ion of the canister assembly 18, rear wheels (not
shown) are provided to aupport the weight of the floor cleaning apparatus
10. A second set of whc;els (also not shown) allow the operator to raise and
lower the nozzle assemb ly 16 through selective manipulation of the height
adjustment switch 28. auch a height adjustment mechanism is well known
in the art and is exempla Pied, for example, by the arrangement incorporated
into the Kenmore Progr~~;ssive vacuum cleaner currently available in the
marketplace. To allow i:or convenient storage of the floor cleaning
apparatus 10, a foot latc;;h 30 functions to lock the canister assembly 18 in
an upright position, as s~~own in Figure 1. When the foot latch 30 is
released, the canister as,wmbly 18 may be pivoted relative to the nozzle
assembly 16 as the floor cleaning apparatus 10 is manipulated to clean the
floor.
The canister assc::mbly 18 also carries an internal chamber 32 that
houses a suction generator 33 (i.e. a state of the art fan and motor
combination) and a dirt collection vessel 34 for removing dirt or dust
entrained in the air stre~im as it passes from the nozzle assembly 16 to the
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suction generator. The canister assembly 18 may also carry a final filtration
cartridge 48 to trap small particulates and prevent their reintroduction into
the environment througl~~ the exhaust air stream.
The nozzle assena.bly 16 includes a nozzle and agitator cavity 36
that houses multiple rot;~,tW g agitators 38. The agitators 38 shown are each
independently and rotat~.bly driven by a motor 40 and cooperating ge2~r
drive 42 housed within the agitator and described in greater detail below
(see Figures 2 and 3). Its the illustrated floor cleaning apparatus 10, the
scrubbing action of the rotary agitators 38 and the negative air pressure
created by the suction gE;nerator 33 cooperate to brush and beat dirt and
dust from the nap of the: carpet being cleaned and then draw the dirt and
dust laden air from the ~~gitator cavity 36 to the dirt collection vessel 34.
Specifically, the dirt an~i. dust laden air passes serially through a suction
inlet and hose and/or an. integrally molded conduit in the nozzle assembly
16 andlor canister assenubly 18 as is known in the art. Next, it is delivered
into the dirt collection vessel 34 held in the chamber 32. The vessel 34
serves to trap the suspended dirt, dust and other particles inside while
allowing the now clean ;sir to pass freely through the porous wall thereof
and then through the sucaion generator 33, final filtration cartridge 48 and
ultimately to the enviror...xnent through the exhaust port 50.
As illustrated, the dirt collection vessel 34 takes the form of a dust or
filter bag of a type well :mown in the art. Of course, it should be
appreciated that the dirt collection vessel could also be a dirt cup or even a
cyclonic separation charuber if desired. Essentially substantially any vessel
capable of collecting dirt may be utilized.
Reference is now made to Figures 2 and 3 which show the mounting
of the agitator motor 40 and associated gear drive 42 in one of the agitators
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38 in detail. As shown, the agitator 38 is mounted for rotation relative to
the nozzle assembly 16. Specifically, a first end of the agitator 38 includes
an end cap 52 which is ;supported on bearings 54 on a stub shaft 55 held in
mounting block 56 keyed. into slot 58 in the side of the nozzle assembly 16.
An end cap 60 at the opposite end of the agitator 38 is supported on
bearings 62 mounted on the housing 64 of the motor 40. As should be
appreciated, the motor ~ECI is fixed to the nozzle assembly 16 by means of
the mounting block 66 i'_i:~ced to the motor housing 64 and keyed in the; slot
68 in the side of the no~ate assembly.
The motor 40 drives a shaft 70 including gear teeth 72. The drive
shaft 70 extends througai a bearing 74 held in the hub 76 of the planetary
gear set earner 78. In tla.e most preferred embodiment a fan 80 is keyed or
otherwise secured to tht: distal end of the drive shaft 70.
The planetary ge~u set carrier 78 includes three stub shafts 82 that
each carry a planetary g~;ar 84. Each of the planetary gears 84 include teeth
that mesh with the gear teeth 72 of the drive shaft 70. Additionally, the
planetary gears 82 mesh with the teeth of an annular gear 86 that is fixed to
the agitator motor hous:cng 64 by pin or other means. Thus, it should be
appreciated that as the drive shaft 70 is driven by the motor 40, the
planetary gears 84 are d~-a.ven around the annular gear 86, thereby causing
the planetary gear set carrier 78 to rotate. Planetary gear set carrier 78
also
includes a drive ring 88 and associated rubber drive boot 87 which includes
a series of spaced channels 89 that receive and engage axial ribs 91
projecting inwardly radially from the inner wall of the agitator 38. Thus,
the rotation of the planetary gear set earner 78 is transmitted by the drive
ring 88 and drive boot l37 directly to and causes like rotation of the
agitator
38. The rubber drive b~:~ot 87 provides the necessary damping to insure the
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smooth transmission of power to the agitator. Simultaneously with the
rotation of the planetary l;ear set Garner 78 and agitator 38, the drive shaft
70 also drives the fan 8() at a ratio ofbetween 4-1 to 10-1 (e.g: 6-1) with
respect to the agitator 3~~.. The resulting rapid rotation of the fan 80 helps
to
ensure proper cooling of the agitator motor 40 during its operation.
More specifically, the floor cleaning apparatus 10 of the present
invention incorporates v novel air cooling system or circuit, which will now
be described in detail. :specifically, air is drawn into the floor cleaning
apparatus 10 through a went 90 at the upper rear face of the nozzle assembly
16 by operation of the suction generator 33 (note action arrow A in Figure
2). Specifically, the air ;F.ixst passes through a filter (not shown) of foam
rubber or other appropriate material into the illumination compartment 94
defined between the up).~er transparent window 96 and the lower
transparent window 98 ~~rhich allow viewing of the operation of the agitator
38. This air then passes over and around the light source 100 so as to
provide cooling thereto ;note action arrows B in Figure 2). Next, the air is
drawn through the pass~~,geway 102 in the nozzle assembly 16 and around
and through an openings 104 in the end cap 52 (note action arrow C). The
air then moves thrnugh i:he lumen of the agitator 3 8 to the fan 80 driven by
means of the agitator drive motor 40 (note action arrows D). The fan 80
forces the air through o.yenings 106 in the planetary gear set carrier 78 (see
also Figure 3) and then siround the.annular gear 86 before it passes through
the housing 64 of the motor 40 (note action arrows E and F}.
After passing ov~;r~ the windings and other internal components (not
shown) of the agitator rr~otar 40 for purposes of heat exchange and cooling,
the air passes through the passageway 108 into the manifold 110 (note
action arrow G). Maniivyld 110 includes an outlet (not shown) in fluid
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communication with the; tigitator cavity 36. Of course, as noted above, the
agitator cavity 36 is in ckirect fluid communication with a suction inlet 44
that leads through the hose 46 into the dirt collection vessel 34 in chamber
32.
5 While only one a.~~itator 38 has been illustrated and described in
detail, it should be appr~:;ciated that both agitators 38 have identical
structures: that is, each ,a.gitator 3 8 has its own drive motor. As a result,
the
agitators 38 are indepen.nently driven. The agitators 38 may be driven by
their individual, ind~pen.dent internal motors in different directions and/or
10 even at different speeds as desired to provide the greatest cleaning
efficiency. Thus, desigy flexibility and performance are all maximized.
The foregoing description of a preferred embodiment of the
invention has been presented. for purposes of illustration and description. It
is not intended to be ex&mustive or to limit the invention to the precise form
disclosed. Obvious modifications or variations are possible in light of the
above teachings. For e:e.ample, while two agitators are illustrated, it should
be appreciated that thre~E; or even more could be provided.
The embodiment: was chosen and described to provide the best
illustration of the principles of the invention and its practical application
to
thereby enable one of oc~dinary skill in the art to utilize the invention in
various embodiments a~~.d with various modifications as are suited to the
particular use contemplF~ted: All such modifications and variations are
within the scope of the invention as determined by the appended claims
when interpreted in accordance with the breadth to which they are fairly,
legally and equitably errtitled.
