Note: Descriptions are shown in the official language in which they were submitted.
08
~AND ~ACUUM CL~`AN~
Background of the Invention
This invention pertains to the art of vacuum cleaner
devices and more particularly to a hand vacuum cleaner.
~he invention is ~articularly applicable as a device
for suction cleaning items and places where conventional larger
sized vacuums are inconvenient and, more particularly, where a
hand held vacuum with a revolying brush that provides a
vibrating and sweeping action is particularly advantageous.
Yarious forms and types of hand vacuums have
heretofore been suggested and employed for both commercial and
domestic use, all with varying degrees of success. It has been
found that these prior hand vacuums have suffered from a -'
variety of problems which limit their practical and economic
lS value.
A principal problem with these prior art devices is
that in order to obtain powerful suction with a ~e~olvin~ brush
the hand vacuums have been relatively heavy since they have
typically been constructed of a metal casing to support a
powerful suction motor and absorb the vibrations of a revolving
brush. In addition, it has been found that a metal casing has
been necessary to withstand the forces of impinging articles
against the casing walls which have been propelled against the
walls by the cleaner during operation. Mere lightweight
plastic materials ha~e been unable to withstand the forces of
such impinging articles over a period of time without risk of
damage to the casing itself, or, at worst, propelling an item
out from a broken casing towards an operator of the cleaner.
Another common problem with hand held vacuum cleaners
is the provision of a convenient yet effective means for
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sealing a dirt and soil collecting bag to the cleaner housing.
It is important that the bag may be easily separable from the
cleaner ~or emptying, but it is also important that a dust
tight seàl be made upon reattachment of the bag to the cleaner
5 and that such dust tight seal must be c`apable of being
maintained over a ~arge number of operations of removal and
reattachment of the ba~. Most conventional type hand vacuum
cleaners which merely use an elastomeric gasket in combination
with a mechanical camming device to seal the bag to the vacuum
lQ housing have been unsuccessful over a period of time due to
deformation of the gasket and mechanical relaxation of the
camming parts. As dust leaks from such a hand vacuum during
operation, it is particularly noticeable to an operator and,
accordingly, a most unattractive and undesirable type of
c~eaner fail~re.
A~other problem with ~rior hand held vac~um cleaner
designs, and particularly those including a revolving brush in
the cleaner nozzle, is the pro~ision o~ a~ e~icient means of
translating the torque forces from the motor to the fan and
revolving brush while minimizing vibration to the housing and
bearing elements and to maintain these elements in the assembly
in a secure manner. Typically, prior art designs have employed
mechanical fastening devices which have not only added weight
to the construction, but are still susceptible to loosening due
to the vibrational forces of the cleaner.
Yet another problem with prior hand held vacuum
cleaner designs has been the disadvantages associated with
cooling the vacuum motor with working air laden with dirt and
dust particles. Due to the desirability of keeping a hand
vacuum as compact as possible, problems have developed in
designing a cooling air flow path which could be segregated
from the working air.
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Yet another problem with hand held vacuum cleaners due
to their compactness has been tbe interference of objects drawn
in by the working air with the Yacuum fan after the par~icles
: have been collected into the vacuum bag when they are not
inhi~ited from rolling back to the fan after the cleaner has
been turned off. This is a particular problem in hand held
vacuum cleaners where the cleaners are operatet in a variety of
different positions and situations and it is likely for
gravitational forces to urge solid objects back towards the
nozzle of the cleaner.
The present invention contemplates a new and improved
hand racuum cleaner which overcomes all the above referred to
problems and others to provide a new hand vacuum which is
simple in design, economical to manufactureO compact and
lightweight, but pro~ides powerful suction action with a
revolving brush, readily adaptable to a plurality of uses in a
variety of cleaning situations, easy to assemble, easy to
operate, easy to detach, empty and reattach the cleaner bag and
which provides improved hand vacuum cleaner operation~
2~ Brief Summary of the Invention
It is an aspect of this invention to provide a hand-held vacuum
cleaner having a housing, rotating brush and selectively-separable bag
assembly; said housing including a bag attachment collar having a recessed
slot areaj said bag assembly including an elastomeric retaining ring having a
sealing and retaining bead for reception in said recessed slot area, said ring
including a lead-on flange and a bag assembly attachment flange, said bead
depending radially inwardly from said flanges and being positioned generally
intermediate of said flanges whereby said bag assembly is positively sealed
during cleaner operation to substantially preclude passing of dust particles.
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Br-ef Descriptian of the Draw~ngs
The invention may take physical form in certain parts
and arrangements of parts, the preferred embodiment of which
will be described in detail in the specification and
illustrated in the accompanying drawings which form a part
hereof and wherein:
FIGURE 1 is a side elevational view of a hand vacuum
formed in accordance with the present invention;
FIGURE lA is a cross-sectional view taken along line
lA-lA of FIGURE 1 particularly illustrating assembly aid wire
grooves in the vacuum handle;
FIGURE 2 is an enlarged cross-sectional view of the
hand vacuum housing;
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FI~URE 2A is an enlarged sectional view of FIGURE 2
particularly illustrating the tongue in groove assembly of the
housing;
FIGURE 2B is a cross-sectional view taken along line
2B-2B of FIGURE 2A;
FIGURE 2C is an enlarged sectional view of FIGURE 2
particularly showing the elastomeric retaining ring of the bag
assembly as i~ is received on the hand vacuum housing;
FIGURE 2D is an enlarged sectional view of FIGURE 2
taken along lines 2D-2D particularly showing an air vent slot
construction;
FIGUR~ 3 is a cross-sectional view taken along line
3-3 of FIGURE 2;
FIGURE 4 is an enlarged front elevational view with
partial cutaways in section of the present invention;
FI~UR~. 5 is a cross-sectional view taken along line
5-5 cf FIGURE 4;
FI WR~ 6 is a cr~ss-sectional view taken alon~ line
6-6 of FIGURE 4; and
FIGURE 7 is an enlarged elevational view in partial
section of the motor and fan assembly.
Detailed Description of the Invention
Referring now to the drawings wherein the showings are
for purposes of illustrating the preferred embodiment of the
invention only and not for purposes of limiting same, the
FIGU~S show a hand vacuum device comprised of a housing lO and
selectively separable bag assembly 12.
More specifically, and with reference to FIGURES 1 and
2, the vacuum housinQ 10 includes a motor mount portion 16, a
fan chamber 18, a nozzle 20 and a handle 2Z. An annular bag
i2 ~ 9~
attachment collar 26 ls provided for attachment af the bag
assembly 12 to the housing 10. The collar 26 includes a
recessed slot area 30 extending circumferentially about the
housing 10.
The bag assembly 12 includes an elastomeric retaining
ring 32 having a sealing and retaining bead 34 (FIGURE 2C) for
reception in the recessed slot area 30 whereby the bag assembly
12 is positively sealed during cleaner operation to
substantially preclude passing of dust particles out of the bag
past the retaining ring 32. The retaining ring 3Z includes a
lead on ~lange 36 and a bag assembly attachment flange 38, the
bead 34 depending radially inwardly from these flanges and
being positioned generally intermediate of the flanges. A
receptacle bag 40 of the bag assembly constructed of a
conventionally known cotton twill used for vacuum cleaner bags
is fixed to ring 32 at the bag' assembly attachment flange 38
with a high strength thread 42, ~ bottom wall 46 of the
sealing and retaining ~ea~ 34 contacts a prt~ jectit~n 48 in the
recess slot area 30 and is slightly deformed about the
projection by high contact pressure created by the hoop
strength of the retaining ring 32~ Such a structure provides a
very positive seal and eliminates the problems of fine dust
particles passing out of the bag assembly 12 during operation
of the cl eaner.
Three pressure sur~aces on the bead 34 operate to seal
the ring 32 to the collar ~6. The bottom wall 46 engaging the
projection 48 in the recess slot area 30 produces a high unit
pressure where the projection 48 engages bead 34. It should be
noted that the elastomeric ring 32 possesses a hoop strength
~0 due to its elastomeric nature and it is sized for a close fit
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over the collar 26. The sealing force of the projection 48
engagin~ the elastomeric wall 46 is greater tha~ the air
pressure to leak through the seal and accordingly precludes the
leaking of ~he fine dust particles.
A second pressure surface occurs at the point
designated by numeral 50 in FIGURE 2C at the bead vertical wall
engaging the opposed recess slot area vertical wall. This
pressure is produced by the back pressure in the bag 40 during
operation as a result of the forcing of air into the bag 40.
The third pressure point occurs at an area designated
by the numeral 52 where the sloping wall of ~he recessed slot
area 30 contacts the front wall ~3 of the bead 34 to produce a
pressure area which is the result of the natural hoop strength
of the elastomeric retaining ring and a preselected
interference fit between the ring and the attachment collar.
A pull tab (not shown) is sewn into the retaining ring
32 to facilitate easy separation of the bag assembly 12 from
the housing 10. ~he rin8 32 is sized relative to the collar 26
such that the ring is stretched 5-7% to move the bead 34 into
the recessed slot area 30. Such stretching produces the hoop
strength earlier mentioned. The seal design has been optimized
to give proper and improved sealing while allowing ease in
attachment and removal of the bag assembly. The retaining ring
32 is not only decorative but is constructed to minimize the
material in the part and yet give proper cross-sectional area
to produce a quality seal over repeated stretchings.
With reference to FIGURES Z and 3, the hand vacuum
housing 10 is preferably constructed of a lightweight plastic.
However, most lightweight plastics which are normally
satisfactory for such a housing construc~ion present a problem
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when they are subjected to repeate~ impingements from the kind
of articles which ~ay be sucked in by hand vacuurn. Such
articles comprise small pebbles, coins, screws, nails, etc.,
which, upon being drawn into the fan chamber 18 are oftentimes
propelled against the chamber side walls by the fan before
passing o~t of the chamber with the working air. The present
invention includes a stone shield 60 to block the potentially
damaging effects of such propelled objects.
With continued reference to FIGURES 2 and 3, the
housing 10 contains a motor 62 having a motor shaft 64
supported in bearinB 65 to which a fan 66 is mounted in fan
chamber 18. Working air drawn in through nozzle 20 and through
fan cham~er ingress aperture 68 is expelled from the chamber
through channel 70. Intermediate the housing side wall
periphe~y and the fan 66, the st~ne shield 60 blocks hea~y
ob~ects that n~ay ~e p~ope~led agair,st the ho~sing side ~al~s.
Preferably stone shield 60 is constructed of aluminized cold
rolled steel. It is circumferentially spaced from the fan so
as not to interfere with the fan's rotation and includes a
peri'pheral side wall 72 and a front wall 74. The ~ront wall is
contiguous to the nozzle 20 and comprises the ingress aperture
68 for the working air. The side wall 72 includes an upper
portion tapered away from the front wall 74 to preclude
perpendicular impingement of the items against the side wall
over that portion. After impingement against the stone shield,
objects are communicated out of the fan chamber 18 through the
channel 70.
With particular reference to FIGURES 2 and 7, the
present invention includes an improved structure for mounting
the fan 66 to the motor 62. Projecting out from the motor
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mount portian 16 of the housing 10 and in~o the fan chambers 18
i~ the motor sha~t 64 supported in bearing 65. This shaft is
driven in rotation by the motor. The shaft 64 includes three
portions. A first portion or support shoulder 80 having a
generally cylindrical configuration is loosely received in a
fan first bore chamber 82 defined by fan bore lead-on flange 83
and fan counterbore shoulder 85. Depending from the support
shoulder portion 80 is a tapering fan bore locking surface 84.
The end portion of the shaft 64 comprises a th~eaded portion
86. It is to be particularly noted that shaft locking surface
84 is closely received against a tapered wall portion 88 of the
fan 66 such that the mating tapers of surface 84 and wall
portion 88 can cooperate through en8agement to lock the fan 66
to the shaft 64 upon sufficient urging of the fan 66 towards
the motor 62. In other words 7 the mating reception of the
shaft taper into the fan bore 'taper locks the fan to the motor
shaft when the fan is sufficiently pressed onto the motor shaft.
S~icient ~r8in~ is ~eali~ed by threaded reception of
a shaft extension 90 onto the shaft threaded portion 86.
However, the mere fastening of the shaft extension 90 to the
shaft by threading it down until the fan is locked to the motor
shaft is clearly not sufficient to maintain the fan in a
tightly locked condition to the shaft when subjected to the
relatively intense vibration and high speed rotation of the
vacuum motor and shaft. Accordingly, an additional force is
required to continue to tighten the shaft extension 90 onto the
shaft portion 86 while abutting the fan 66 to maintain the
locking reception.
The revolving brush 96 (FIGURES 4 and 6) is rotated by
a belt (not shown) received around the brush at an intermediate
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portion generally immediately below the shaft extension 90.
The belt is received on the shaft extension at ~enerally its
point of lessermost diameter 97 (~IGUR~ 7), The belt is
constructed of an elastomeric material and is stretched over
the distance from the brush 96 to the shaft extension 90 to
maintain a gripping action on both the shaft extension 90 and
the brush 96. During operation of the cleaner, a torque is
applied by resistance of the belt and brush to motor shaft
rotation ~o the shaft extension 90 to continually tighten down
the shaft extension 90 onto the threaded portion 86. The
continual tightening of the shaft extension 90 during operation
continuously urges the shaft extension 90 into abutting
engagement with the fan 66 to urge the fan towards the motor 62
and maintain a tight locking reception of the shaft locking
surface 84 against the fan tapered wa~ portion 88.
Co~entiona~ ~a~ fas~ni~g tech~i4ues s~ch as
aerodynamic sealing or internal threading of the an for
reception on a threaded shaft portion is obviated with the
structure of the present invention. Several advantages of this
structure include the lower cost of production of both the
motor and the fan. Since th~r~ is no necessity to machine or
mold a thrèad on either the fan or motor shaft, manufacturing
cost is less. In addition, assembling cost is also less
because the fan does not have to be spun onto the shaft.
Another advantage is that the positive locking connection
between the fan and the shaft is effected without putting
excessive stress on the fan. Fan internal thread fastening
schemes oftentimes result in large torque and stress forces
being exerted on the threads which possibly distort the fan
3~ during operation. Yet another feature of the present invention
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is that such a fan mounting structure absorbs impact loads on
the fan better. When a foreign ob ject impin~es the fan, the
fan has a greater tendency to give against the load than a
threaded mounti~g structure. This allows the fan to act
somewhat as a shock absorber to heavy objects that are drawn
into the cleaner.
With reference to FIGURES 2, 4, 5, and 6, it may be
seen that the nozzle portion 20 of the present invention houses
the revolving brush 96. The brush 96 includes opposed end
bearings 98 which support the brush and allow its rotational
movement. The nozzle includes integrally formed opposed
bearing housing cavities lO0 sized to closely receive the
bearing housings of the brush. A nozzle guard 102 is fastened
to the nozzle portion 20 with conventional threaded fasteners
lnot shown) inserted into receiving members 104. The nozzle
guard has openings through which brush elements lD~ extend and
through which vacuumed dirt may pass. The guard 102 further
includes bearin~ housing ~etaining elements 106 which impart
the forcè to retain the brush 96 in cavities lO0. The
retaining element 106 is sized such that there is an
interference fit against the bearing 98 due to deflection of
the clip element 106 which holds the brush solid within the
nozzle. The brush 96 is normally unbalanced and will want to
vibrate during operation. There is thus a necessity that the
brush be positively retained in as close a fit as possible to
minimizè vibrational movement.
Another feature of the retaining element is that the
nozzle guard is preferably constructed of metallic material as
is the bearing assembly 98. The retaining element 106 thus can
operate as a source of heat transfer. Since the bearing 98 is
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also in contact with the plastic nozzle housing at the cavities
100, heat must be dissipated through the retaining element 106
and out through the sole plate portion of the nozzle guard
102.
The nozzle guard 102 also includes a locating and
locking protruding dimple 110 disposed for cooperative
association with the nozzle whereby the noz71e and nozzle guard
are in cooperative support. With particular reference to
FIGURE 4, the housin~ 10 is constructed of opposed first and
second half housing elements which mate along a center line
112. To buttress the housing, and in particular the nozzle 20
at the center line, dimple 110 in combination with the nozzle
guard front wall 114 support the nozzle at its terminal end
portion about the center line 112. Such structure minimizes
damage to the cleaner by deflection or separation of the
housing half elements at the nQzzle terminal end portion.
With particular refe~ence to FI~URE 2, it can be seen
that the h~using 10 inc~u~es a motor mo~nt portion 16 ar
receiving the motor 62 that includes a plurality of air vents
120 provided for communicating the ingress and egress of
cooling air to the motor 62. A baffle wall 122 engages the
periphery of the motor 62 to define a motor cooling air inhale
chamber 124 and an exhalle chamber 126. The motor 62 includes a
cooling air fan (not shown) which draws cooling air in through
the YentS 120 of the inhale chamber 124 into air Yents (not
shown) of the motor, through the body of the motor, out motor
vents in the exhale chamber 126 and ultimately out into the
environment through the air vents 120 in the exhale chamber
126. The baffle wall 122 precludes cooling air exhausted from
the exhale chamber 126 from intermixing with air in the inhale
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chamber 124 without passing through the motor 62. In addition,
the vents 120 in exhale chamber 126 include a sloped side wall
127 lFIGURE 2D) contiguous to the baffle wall 122 and the vents
of the inhale chamber 124. The sloped side wall 127
effectively directs the exhaust air towards the rear of the
cleaner and away rom the vents of the inhale chamber 124 to
inhibit mixing of exhaust cooling air with intake cooling air.
With particular reference to FIGUKES 2A and ZB it is
important that the cleaner be sealed in a manner that will
preclude mixing of cooling air and working air so that the
motor 62 is not exposed to vacuumed dirt and yet will provide a
strong and durable seal that is easy to assemble. The
invention employs a tongue in groove mating fit along the
entire periphery of the cleaner between opposing first and
second housing halves and about the periphery of the motor
moun t por ti on 16 .
The housing handle 22~ as may be seen from FIGURE lA,
~urther includes besides the to~e in ~roove sealing, se~eral
assembly aid wire grooves 130 for communicating switch wires
from the cleaner cord 132 to the cleaner on/off switch 134
(PIGURE 1).
The invention has been described with reference to the
preferred embodiment. Obviously, modifications and alterations
will occur to others upon the reading and understanding of the
specification. It is our intention to include all such
modifications and alterations insofar as they come within the
scope of the appended claims or the equivalents thereof.
Having thus described our invention, we now claim:
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