U.S. patent application number 11/761961 was filed with the patent office on 2008-12-18 for upright vacuum cleaner.
Invention is credited to Vincent Bobrosky, Brad Chenoweth, Donald J. DAVIDSHOFER, Ping Fai Fung.
Application Number | 20080307597 11/761961 |
Document ID | / |
Family ID | 39650854 |
Filed Date | 2008-12-18 |
United States Patent
Application |
20080307597 |
Kind Code |
A1 |
DAVIDSHOFER; Donald J. ; et
al. |
December 18, 2008 |
UPRIGHT VACUUM CLEANER
Abstract
A vacuum cleaner brushroll having a pulley with a generally
circular pulley surface surrounding at least one opening located
radially inward of the pulley surface, and an elongated shaft
passing through the central opening. The pulley may surrounds and
be captured in place by a mounting portion of the elongated shaft
that is formed as continuous single structure. A mounting portion
of the shaft comprising a continuous structure having a reduced
cross section into which the pulley fits may be located within and
on either side of the pulley's central opening. A process for
making a brushroll is also provided.
Inventors: |
DAVIDSHOFER; Donald J.;
(Bloomington, IL) ; Bobrosky; Vincent; (Normal,
IL) ; Chenoweth; Brad; (Cooksville, IL) ;
Fung; Ping Fai; (New Territories, CN) |
Correspondence
Address: |
HUNTON & WILLIAMS LLP;INTELLECTUAL PROPERTY DEPARTMENT
1900 K STREET, N.W., SUITE 1200
WASHINGTON
DC
20006-1109
US
|
Family ID: |
39650854 |
Appl. No.: |
11/761961 |
Filed: |
June 12, 2007 |
Current U.S.
Class: |
15/182 ; 15/179;
300/21 |
Current CPC
Class: |
A47L 9/0444
20130101 |
Class at
Publication: |
15/182 ; 15/179;
300/21 |
International
Class: |
A46B 9/02 20060101
A46B009/02; A46B 13/00 20060101 A46B013/00; A46D 3/00 20060101
A46D003/00 |
Claims
1. A vacuum cleaner brushroll comprising: a pulley comprising a
generally circular pulley surface surrounding at least one opening
located radially inward of the pulley surface; and an elongated
shaft passing through the central opening; wherein the pulley
surrounds and is captured in place by a mounting portion of the
elongated shaft that comprises a continuous single structure.
2. The vacuum cleaner brushroll of claim 1, wherein the pulley
comprises a material having a relatively high melting point, and
the mounting portion comprises a material having a relatively low
melting point.
3. The vacuum cleaner brushroll of claim 1, wherein the at least
one opening comprises radially-extending ribs that extend into
corresponding slots in the mounting portion.
4. The vacuum cleaner brushroll of claim 1, wherein the at least
one opening comprises a plurality of openings.
5. The vacuum cleaner brushroll of claim 1, wherein the at least
one opening comprises a non-circular profile.
6. The vacuum cleaner brushroll of claim 1, wherein the pulley
surface comprises a crowned surface adapted to receive a flat belt
or a ribbed belt.
7. The vacuum cleaner brushroll of claim 1, wherein the pulley
surface comprises a plurality of teeth that are adapted to receive
a cogged belt.
8. The vacuum cleaner brushroll of claim 1, wherein the pulley
surface comprises a continuous surface that extends entirely around
the elongated shaft.
9. A vacuum cleaner brushroll comprising: a pulley comprising a
generally circular pulley surface surrounding at least one opening
located radially inward of the pulley surface; and an elongated
shaft passing through the at least one central opening; wherein a
mounting portion of the elongated shaft located within and on
either side of the central opening comprises a continuous structure
having a reduced cross section into which the pulley fits.
10. The vacuum cleaner brushroll of claim 9, wherein the pulley
comprises a material having a relatively high melting point, and
the mounting portion comprises a material having a relatively low
melting point.
11. The vacuum cleaner brushroll of claim 9, wherein the at least
one opening comprises radially-extending ribs that extend into
corresponding slots in the mounting portion.
12. The vacuum cleaner brushroll of claim 9, further comprising: an
opening located at a first end of the elongated shaft; a bearing
cup that at least partially fits within the opening; a bearing that
at least partially fits within the opening; and one or more pins at
least partially positioned within the opening and between the
opening and an outer surface of the bearing cup to thereby hold the
bearing cup in the opening.
13. The vacuum cleaner brushroll of claim 9, further comprising a
plurality of edge cleaning bristles protruding from the elongated
shaft and away from the pulley at an angle of about 45 degrees to
80 degrees relative to the central axis of the elongated shaft.
14. The vacuum cleaner brushroll of claim 13, wherein the edge
cleaning brushrolls protrude from a beveled end portion of the
elongated shaft.
15. The vacuum cleaner brushroll of claim 9, wherein the pulley
surface comprises a crowned surface adapted to receive a flat belt
or a ribbed belt.
16. The vacuum cleaner brushroll of claim 9, wherein the pulley
surface comprises a plurality of teeth that are adapted to receive
a cogged belt.
17. The vacuum cleaner brushroll of claim 9, wherein the pulley
surface comprises a continuous surface that extends entirely around
the elongated shaft.
18. A vacuum cleaner brushroll manufactured by a process
comprising: forming a pulley having a generally circular pulley
surface and at least one opening located radially inward of the
pulley surface; forming an elongated shaft from a continuous piece
of material that passes through the at least one opening and at
least partially surrounds the pulley to structurally interlock the
pulley in place on the elongated shaft.
19. The vacuum cleaner brushroll manufactured by the process of
claim 18, wherein the pulley comprises a material having a
relatively high melting point, and the elongated shaft comprises a
material having a relatively low melting point.
20. The vacuum cleaner brushroll manufactured by the process of
claim 18, further comprising forming radially-extending ribs in the
at least one opening.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to features for use with
vacuum cleaners, such as upright vacuum cleaners, wet extractors,
stick vacuums, canister vacuums, central vacuums, and the like.
BACKGROUND OF THE INVENTION
[0002] Vacuum cleaning devices, such as upright and canister vacuum
cleaners, wet extractors, stick vacuums, electric brooms and other
devices, are in widespread use as a tool to clean floors,
upholstery, stairs, and other surfaces. Known vacuum cleaning
devices have various features that are intended to improve their
cleaning effectiveness. For example, a common feature on upright
vacuums is a rotating brushroll, and numerous variations of such
brushrolls are known in the art. Another feature is the provision
of various types of filtration systems, such as vacuum bags,
disposable or reusable filters, cyclone separators, and
combinations thereof. Still other features relate to controlling
the manner in which the vacuum cleaner addresses the surface being
cleaned, such as nozzle height adjustment mechanisms.
[0003] While the prior art provides various features relating to
cleaning effectiveness and user convenience, there still exists a
need for improvement of and alternative designs for these and other
features of vacuum cleaning devices.
SUMMARY OF THE INVENTION
[0004] In a first exemplary aspect, an embodiment of the invention
provides a vacuum cleaner brushroll having a pulley with a
generally circular pulley surface surrounding at least one opening
located radially inward of the pulley surface, and an elongated
shaft passing through the central opening. The pulley surrounds and
is captured in place by a mounting portion of the elongated shaft.
The mounting portion includes a continuous, single structure.
[0005] In another exemplary aspect, an embodiment of the invention
provides a vacuum cleaner brushroll having a pulley with a
generally circular pulley surface surrounding at least one opening
located radially inward of the pulley surface. An elongated shaft
passes through the at least one central opening. A mounting portion
of the elongated shaft is located within and on either side of the
central opening. The mounting portion includes a continuous
structure having a reduced cross section into which the pulley
fits.
[0006] In another exemplary aspect, an embodiment of the invention
provides a vacuum cleaner brushroll manufactured by a process. The
process includes forming a pulley having a generally circular
pulley surface and at least one opening located radially inward of
the pulley surface, and forming an elongated shaft from a
continuous piece of material that passes through the at least one
opening and at least partially surrounds the pulley to structurally
interlock the pulley in place on the elongated shaft.
[0007] The recitation of this summary of the invention is not
intended to limit the claimed invention, and examples of other
aspects, embodiments, modification and features of the invention
are described herein, and still other aspects, embodiments,
modification and features of the claimed invention will be apparent
to persons of ordinary skill in view of the disclosures herein.
Furthermore, this recitation of this summary of the invention, and
the other disclosures provided herein, are not intended to diminish
the scope of the claims in this or any prior or subsequent related
or unrelated application.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The present invention is described in detail with reference
to the examples of embodiments shown in the following figures in
which like parts are designated by like reference numerals.
[0009] FIG. 1 is an isometric view of a upright vacuum cleaner.
[0010] FIG. 2 is a partially-exploded and fragmented view of a rear
housing for a vacuum cleaner.
[0011] FIG. 3 is a fragmented and partially disassembled view of an
accessory tool and vacuum cleaner housing mount for the accessory
tool.
[0012] FIG. 4 is a fragmented isometric view of the rear housing of
FIG. 2.
[0013] FIG. 5 is a bottom plan view of a filter latch.
[0014] FIG. 6 is a cutaway view of the filter latch of FIG. 5, as
shown along line VI-VI thereof, and as shown mounted to a vacuum
cleaner housing.
[0015] FIG. 7 is a fragmented isometric view of a the filter latch
of FIG. 5, as shown mounted to a vacuum cleaner housing.
[0016] FIG. 8 is an exploded view of a dirt separation system for a
vacuum cleaner.
[0017] FIG. 9 is a schematic diagram illustrating the airflow
through the dirt separation system of FIG. 8.
[0018] FIG. 10 is an exploded isometric view of a dirt cup and cam
plate assembly.
[0019] FIG. 11 is an oblique front view of the dirt cup of FIG.
10.
[0020] FIG. 12 is an oblique from view of the dirt cup and cam
plate assembly of FIG. 10.
[0021] FIGS. 13A, 13B and 13C are panoramic schematic diagrams
illustrating the operation of a dirt cup and cam plate
assembly.
[0022] FIG. 14 is an exploded isometric view of a vacuum cleaner
base.
[0023] FIG. 15 is a partially cut away view of a wheel mounting
arrangement for a vacuum cleaner base.
[0024] FIG. 16 is an exploded isometric view of a vacuum cleaner
brushroll.
[0025] FIG. 17 is a fragmented and exploded isometric view of a
vacuum cleaner brushroll.
[0026] FIG. 18 is an exploded isometric view of a vacuum cleaner
base.
[0027] FIG. 19 is a cutaway view of a connection between a vacuum
cleaner base and rear housing.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTIONS
[0028] The present disclosure provides numerous inventive features
for vacuum cleaners. For brevity, a number of these features and
alternative embodiments of the invention are described with
reference to their exemplary use in an upright vacuum cleaner, such
as the vacuum cleaner 100 shown in FIG. 1. It will be appreciated
however, that the features described herein can be used in various
other contexts. For example, the various features described herein
can be used with canister vacuums, stick vacuums, portable and
handheld vacuums, shop vacuums, wet extractors, central vacuum
systems, and so on. Furthermore, the various features described
herein may be used separately from one another or in any
combination thereof. The present disclosure illustrating the use of
the various inventions described herein are not intended to limit
the inventions in any way.
[0029] As shown in FIG. 1, the exemplary vacuum cleaner 100
comprises a base 102 to which a rear housing 104 is pivotally
mounted. The base 102 is supported for movement over the ground by
a pair of rear wheels 106 and a front wheel carriage (not visible)
which will be described elsewhere herein. A grip 108 is provided at
the top of the of the rear housing, and is shaped to receive an
operator's hand, as known in the art.
[0030] The vacuum cleaner 100 may be powered by an electrical cord
(not shown) or batteries (not shown), as known in the art. One or
more power controls 110 are provided on the vacuum cleaner. Such
controls 110 may be located anywhere on the vacuum cleaner, such as
on the rear housing 104, the base 102, or on an associated power
cord (not shown). The exemplary power control 110 is provided on
the rear housing 104 at a position approximately half way up the
housing, which allows the grip 108 and a portion of the rear
housing 104 connected to the grip 108 to be easily removed from the
vacuum cleaner 100 to make it more compact for shipping. In the
shown embodiment, the power control is used to operate a vacuum
motor (not shown), but other controls may be provided such as a
separate brushroll motor control, wet extractor fluid deposition
controls, and the like.
[0031] The vacuum cleaner 100 also includes a dirt collection
system. Typical vacuum cleaner dirt collection systems include
bags, cyclone chambers, and filters, and any such device may be
used with various embodiments of the invention. In the shown
exemplary embodiment, the dirt collection system comprises a
removable dirt cup 112 and cyclone chamber 802 (FIG. 8) that are
located on the rear housing 104. Alternatively, the dust collection
bin 112 and/or cyclone chamber 802 may be replaced by another type
of device, and may be partially or entirely mounted on the base
102. For example, a suitable alternative dust collection device
would be a bag chamber or external bag that is mounted on the base
102 or rear housing 104.
[0032] A suitable vacuum fan and motor 902 (FIG. 9) are provided in
the base 102 or rear housing 104, as known in the art. Such vacuum
fans and motors typically comprise an electric motor that operates
a suction fan to generate a working airflow through the vacuum
cleaner 100. The working airflow picks up debris from a surface
being cleaned, and deposits such debris in the dirt collection
system. In some cases, the working airflow passes through the
suction fan before it is deposited into the dirt collection system
(in which case the dirt collection system operates at higher than
atmospheric pressure), and in other cases the working airflow
passes through the dirt collection system before it passes through
the suction fan (in which case the dirt collection system operates
a lower than atmospheric pressure). Embodiments of the invention
may be used with either type of system.
[0033] Referring now to FIG. 2, the details of an embodiment of a
rear housing 104 are shown and described in more detail. As may be
seen in FIG. 2, the rear housing shown in this embodiment is
generally the same as the embodiment of FIG. 1, but differs in that
this embodiment comprises a dual control system having a first
control 110A that is used to provide primary power to the machine
and a second control 110B that is used to control only a brushroll
motor that is located in the base housing. Such a brushroll motor
is described subsequently herein.
[0034] Located at the top of the rear housing 104 (or elsewhere on
the vacuum cleaner 100) is an optional accessory cleaning tool 202.
The tool 202 fits within a corresponding recess 204 in the rear
housing 104. An exemplary manner in which the accessory cleaning
tool 202 can be mounted to the rear housing 104 is shown in greater
detail in FIG. 3. Here, it can be seen that the accessory cleaning
tool 202 is provided with an opening 302 located on the rear
portion of the tool housing 306, and this opening 302 fits over a
pair of snap fingers 304 located within the recess. The snap
fingers 304 and opening 302 are shaped and sized such that one or
both of the snap fingers 304 must be flexed towards one another to
fit into the opening 302, and, once inserted, are held in place by
corresponding ridges or other shapes on the fingers 304 and/or
opening 302. The accessory cleaning tool 202 is installed in the
rear housing 104 by resting a front portion of the tool 206 into a
corresponding lower portion 208 of the recess 204 and pressing the
accessory cleaning tool 202 into the recess 204 to engage the
opening 302 snaps with the snap fingers 304.
[0035] The accessory cleaning tool 202 may comprise any
conventional accessory tool for a vacuum cleaner, such as a crevice
tool, upholstery brush, duster, or floor brush. In the present
case, the accessory cleaning tool 202 comprises what is known as a
turbo tool, which is an accessory tool that uses a turbine that is
operated by the suction air flow from the vacuum cleaner to drive a
brushroll located in the tool. The turbine can use clean air drawn
from above the surface being cleaned, or dirty air drawn from the
surface itself. Such devices are generally known in the art,
however, the present invention provides a unique divergence from
conventional designs. In particular, the accessory cleaning tool
202 comprises a housing 306 having an inlet at one end 206, and an
outlet 308 at the other end, as known in the art, but the outlet
308 is shaped as a receptacle into which a corresponding accessory
suction hose telescopically fits. This differs from typical prior
art constructions, in which the outlet is formed as a receptacle
that protrudes from the end of the housing 306. The present
stemless construction is expected to provide a number of advantages
over conventional turbo tool designs. For example, the stemless
turbo tool is more compact than conventional devices, and can be
better integrated into a recess 204 in the vacuum cleaner housing.
In addition, the outlet 308 and recess 204 may be shaped such that
the stemless outlet 308 provides an opening 114 into which a user
can insert a finger to help remove the accessory cleaning tool 202
from the housing 104, as best seen in FIG. 1.
[0036] Referring again to FIG. 2, in the shown exemplary
embodiment, the vacuum cleaner includes a cyclonic-type primary
dirt separation system having a cyclone chamber 802 located above a
dirt cup opening 210 into which the dirt cup 112 can be selectively
installed. The opening 210 is provided on the front face of the
rear housing 104, but it will be understood that the opening 210
can be located on other sides of the housing 104, on the back of
the housing 104, or on the base 102. In addition, while the opening
210 is shown as a hollow recess into which the dirt cup 112 fits,
it may instead comprise a shelf-like structure onto which a dirt
cup 210 fits. This latter construction is sometimes used when a
cyclone chamber is provided as an attachment to the top of the dirt
cup 210, or when the dirt cup 210 itself forms a cyclone chamber.
These alternative constructions are, of course, possible with
embodiments of the present invention. As suggested before, the
present disclosure also contemplates that the cyclone and dirt cup
210 can be replaced by a vacuum bag contained in the opening 210 by
a removable cover or chamber in other embodiments.
[0037] Located at the bottom of the dirt cup opening 210 (or bag
chamber) is a filter chamber 214 into which an optional pre-motor
filter 212 can be installed. The pre-motor filter 212 is provided
between the primary dirt collecting system and the vacuum fan, and
serves as an additional dirt filtration stage. In the shown
exemplary embodiment, air exiting the cyclone 802 and dirt cup 112
enters the filter chamber 214 through an inlet 238 located at the
rear of the chamber 214, passes through the filter 212, and exits
to the vacuum fan through an outlet 240 located at the bottom of
the chamber 212. The outlet 240 may include a grate-like structure
to help prevent large particles from passing to the vacuum fan if
the filter 212 catastrophically fails, or if the vacuum cleaner 100
is operated without the filter 212 in place.
[0038] The pre-motor filter 212 may comprise any suitable
filtration medium or media. In the shown exemplary embodiment, the
pre-motor filter 212 comprises a foam first filter layer 212' and a
paper or non-woven second filter layer 212'' that may be mounted in
a filter tray 213. One or both of the layers 212', 212'' may be
removable from the tray 213 to allow them to be cleaned separately.
Any suitable filter media may be used, such as open-cell foams,
electrostatic filters, and high efficiency (HEPA, ULPA, etc.)
filters, and such filters may be shaped in any suitable way, such
as being flat, pleated, conical, cylindrical, and so on.
[0039] The filter tray 213 is provided to give structural support
to the filter layers 212', 212''. In addition, the pre-motor filter
tray 213 may be provided with features to help control the airflow
in the filter chamber 214 to ensure that the air generally passes
through the filter 212 instead of going around it. In the shown
exemplary embodiment, the filter tray 213 includes an opening 242
that corresponds with the inlet 238 into the pre-motor filter
chamber 214 to provide airflow to the filter 212. An overmolded
perimeter seal 213' surrounds the opening 242 and fits against the
pre-motor filter chamber inlet 238 to seal airflow therethrough.
The perimeter seal 213' (or a separate seal, if desired) also
extends around the filter tray 213 to seal against the internal
walls of the filter chamber 214 and help prevent air from bypassing
the filter 212 on its way to the chamber outlet 240. Thus, the
filter tray seal 213 provides two seals to prevent air from
bypassing the filter 212. Of course, other types and configurations
of seals may be used, if desired.
[0040] In the exemplary embodiment, the filter camber 214 is open
towards the dirt cup opening 210, and the filter 212 is inserted
into the chamber 214 by removing the dirt cup 112 and placing the
filter into the chamber 214. The top of the filter chamber 214 is
closed by a trap door 216, which fits over and encloses the filter
212 when it is installed. The trap door 116 may be pivotally
mounted by pivots 216' that fit, for example, into corresponding
bosses in the dirt cup opening 210 or filter chamber 214. In such
an embodiment, the trap door 216 can be pivoted upward to insert or
remove the pre-motor filter 212. In order to ensure that the user
is aware of the presence for the pre-motor filter, the trap door
216 may be provided with suitable markings and/or made from a
transparent material that allows the user to see the filter.
[0041] The exemplary trap door 216 also includes a door seal 216''
that is molded into or adhered to the bottom of the trap door 216
to seal against the top of the filter tray 213. This forms a seal
that prevents air from leaking into the filter 212 through the trap
door 216, which could decrease the efficiency of the vacuum cleaner
100. To further help with sealing, the dirt cup 112 might also be
equipped to press down on the trap door 216 and filter tray 213
when it is installed, which will help the tray perimeter seal 213'
and door seal 216'' form airtight seals.
[0042] Other arrangements for the pre-motor filter may, of course,
be used with other embodiments. For instance, the trap door 216 may
be installed or mounted in other ways, such as by being provided as
a simple removable cover that fits over the filter 212 after it is
installed. As another example, the filter tray 213 may include an
integral or removable cover to replace the trap door 216. Such a
cover would seal over the top of the filter 212 and provide an
enclosed air path from the tray opening 242 to the chamber outlet
240. In such a case, the filter tray 213 may be held in place by
fasteners or by being pressed down by the dirt cup 112 when the cup
112 is installed. Other arrangements for mounting pre-motor filters
are known in the art, and may be used with other embodiments of the
present invention, as will be appreciated by those of ordinary
skill in the art in view of the present disclosure.
[0043] The pre-motor filter 212, filter tray 213, chamber 214
and/or trapdoor 216 may be equipped with a lockout feature that
prevents the vacuum cleaner 100 from operating when the filter 212
is removed. Electrical microswitches that detect the presence of
the filter 212 and spring-loaded mechanical locks that prevent
insertion of the dirt cup 112 when the filter 212 is absent are
examples of such devices. These and other devices are generally
known in the art.
[0044] Also located on the rear housing 104 is an optional
post-motor filter 218 for filtering air that exits the vacuum fan.
The post-motor filter 218 may be any suitable type, shape, or
performance grade. An exemplary pleated HEPA ("high efficiency
particle air") filter is shown. The post-motor filter 218 fits into
a post-motor filter recess 220 located, in the exemplary
embodiment, towards the bottom of the rear housing 104 and
immediately adjacent the vacuum fan outlet 244.
[0045] A post-motor filter cover 222 may be provided to fit over
the post-motor filter 218 and hold it in place in the second recess
220. As shown, the post-motor filter cover 222 may comprise an
assembly of multiple parts 222A, 222B that are assembled together
to provide the required structure and/or aesthetic appearance. Of
course, the multiple parts may instead be formed as a single molded
or formed part. Furthermore, the cover 222 may be attached to the
filter 218, or formed as part of the filter 218 itself. The
post-motor filter cover 222 is held in place at its bottom end by a
tab 224 that fits into a corresponding notch 226 located in the
second recess 220 (or vice-versa). At its top, the post-motor
filter cover 222 is attached to the rear housing by a filter latch
228. The filter latch 228 compresses the filter cover 222 against
the post-motor filter 218 to help seal the post-motor filter 218
against the vacuum fan outlet 244. This seal helps ensure that air
exiting the vacuum cleaner 100 is filtered before exhausting to the
atmosphere.
[0046] Referring to FIGS. 4 through 7, the construction and
operation of the exemplary filter latch are described in greater
detail. As shown in FIG. 4, the filter latch is located at the
bottom of the pre-motor filter recess 214, but it may located
elsewhere. FIG. 5 is a bottom view of the filter latch 228, FIG. 6
is a cut-away side view of the filter latch as seen along line
VI-VI of FIG. 5 and at is appears when installed in the housing,
and FIG. 7 is a partially cut-away isometric front view of the
portion of the filter recess 214 at which the filter latch 228
mounts.
[0047] As shown in FIGS. 5 and 6, the filter latch comprises a
generally circular device having a handle 502 extended from its
perimeter. The handle 502 may, of course, be replaced by any
suitable gripping structure. The filter latch 288 has a generally
dome-like shape that opens downwardly, and a number of protrusions
that extend downward generally within the dome-like structure. The
first protrusion is a boss 504 that is used to pivotally mount the
filter latch 228 to the housing in the filter recess 214. As shown
in FIGS. 6 and 7, the housing 214 has a corresponding hole 702 into
which the boss fits and, when so installed, a screw 604 is threaded
into the bottom of the boss 504 to fix the latch 228 in place. The
screw 604 is tightened enough to hold the latch 228, but does not
clamp the latch 228 against the wall of the recess 214. This can be
accomplished by making the boss 504 protrude slightly beyond the
thickness of the recess wall, as shown, providing a shoulder on the
screw 604, or by other suitable means. Once installed, the filter
latch can pivot back and forth through an arc of travel as shown by
the arrow in FIG. 7. The range of this rotational travel is limited
by a pair of protrusions 704 that extend up from the surface of the
filter recess 214.
[0048] A latching arm 506 also extends downwardly from the bottom
of the filter latch 228. The latching arm 506 extends through a
corresponding slot 706 through the bottom of the filter recess 214.
The slot 706 is generally arcuate in shape and extends far enough
to allow the latch arm 506 to move unobstructed as the filter latch
228 is rotated to the limits of its travel. The latch arm 506 is
shaped and positioned to engage with a corresponding hook 230
located on the top of the post-motor cover filter 222 (see FIG. 2).
When the filter latch 228 is rotated to its counterclockwise
position, the latch arm 506 clears the hook 230, and allows the
post-motor filter cover 222 to be removed from the rear housing
104. When the filter latch is in its full clockwise position, the
latch arm 506 engages the hook 230 and holds the post-motor filter
cover 222, and thus the filter 218, against the housing 104. The
hook 230 and/or the latch arm 506 may be provided with a cam
surface or ramp-like shape that causes the latch arm 506 to apply
progressively greater force to pull the hook 230 (and thus the
cover 222) against the housing 104. The use of this filter latching
arrangement allows the user to use relatively little effort to
press the post-motor filter 218 into place with a relatively large
amount of force. This is an improvement over prior art post-motor
filters and filter covers that required the user to exert a
relatively great amount of force to lock the filter in place and
form a seal between the filter and the vacuum outlet.
[0049] The filter latch 228 is also provided with a feature that
snaps it into the locked position. In one embodiment, this feature
can simply comprise a detent located on the camming surfaces
(either the hook 230 or the latch arm 506). In another exemplary
embodiment, shown in FIG. 7, this feature comprises a third
protrusion 508 extending from the bottom of the filter latch 228,
which protrusion 508 is positioned to engage with a corresponding
protrusion 708 extending from the bottom of the filter recess 214.
When the filter latch 228 is rotated in the far clockwise position,
the cam lock protrusion 508 snaps over filter recess protrusion 708
and holds the filter latch 228 in position. Of course, any other
suitable detent or holding device may be used instead.
[0050] In the exemplary embodiment, the filter latch 228 is located
within the pre-motor filter recess 214, which is subjected to the
negative pressure generated by the vacuum fan when it is operating.
In contrast, the latch arm 506 extends through the wall of the
recess 214 to an area that is at ambient pressure. Thus, there may
be a tendency for air to bleed through the slot 706 or the hole 702
from the atmosphere into the post-motor filter chamber 214 vacuum,
and thence into the vacuum fan. Such an air leak might reduce the
efficiency of the vacuum cleaner 100. To counteract such air
bleeding, the filter latch is provided with an annular facing seal
602 that is arranged to surround both the screw boss 504 and the
latch arm 506. The seal 602 engages a corresponding cylindrical
wall 710 that extends slightly upwards from the filter recess 214
and helps prevent air from passing through the boss hole 702 and
latch arm slot 706. Of course, other seal arrangements may be used
instead, and the seal 602 may be omitted if the filter latch 228 is
positioned to be at a location where air bleeding is not an issue,
such as on the exterior of the housing 104.
[0051] Referring back to FIG. 2, the rear housing 104 also
includes, at its lower end, various features to allow it to be
mounted to the base 102. For example, the rear housing 104 may
include a cylindrical mounting boss 236 that pivotally engages a
corresponding structure on the base 102. While a conventional
mounting arrangement may be used in some embodiments, the present
disclosure also provides an example of a novel pivoting mounting
arrangement that may be used with the boss 236 subsequently herein.
Located radially outward form the mounting boss 236 are a first
protrusion 232 and a second protrusion 234. The protrusions 232,
234 are positioned to engage the protrusion 1436 of a corresponding
handle release mechanism 1434 (FIG. 14) to lock the rear housing
104 in a full upright position and a reclined position relative to
the base 102, as generally known in the art or described elsewhere
herein.
[0052] Referring now to FIGS. 8 and 9 an embodiment of one dirt
separation system that may be used with the vacuum cleaner of the
present invention is described in detail. In the shown embodiment,
the dirt separation system comprises a cyclonic separator having a
removable dust bin located below it. As noted before, other types
of cyclone separators, multi-stage cyclone separators, water
filtration separators, wet extractor recovery tanks, dust
collection filtration bags, and the like, may be used. The
exemplary cyclone separation system comprises a cyclone chamber 802
having an inlet 804 that can be connected to one or more suction
inlets on the vacuum cleaner 100. The inlet 804 extends into the
cyclone chamber by way of a helical ramp 806, which induces a
downward motion to the incoming air and, because the inlet 804
enters the cyclone chamber 802 in a tangential manner, also induces
a swirling motion in the airflow. Alternatively, the inlet may be
perpendicular to the cyclone chamber 802, in which case it may be
desirable to include an airflow diverting structure to initiate
cyclonic airflow motion within the cyclone chamber 802. A gasket
824 may be provided at the bottom of the cyclone chamber to seal
against the top of the dirt cup 112.
[0053] As shown by the arrows in FIG. 9, the air enters the cyclone
chamber and begins a cyclonic motion therein. Located below the
cyclone chamber is the dirt cup 112. As the air circulates within
the cyclone chamber 802 and the dirt cup 112, dirt and other
entrained solids fall out of the airstream and are deposited in the
dust collection chamber 112. The air then circulates up and around
a cyclone filter 816 which is mounted over the cyclone outlet 808.
As shown, the cyclone filter 816 comprises a perforated shroud 816'
having a disk-like plate 816'' attached to its bottom end. The
plate 816'' helps prevent particles and objects from rising up and
covering or entering the shroud 816'. It will be appreciated that
the disk-like shroud may be removed or modified in other
embodiments, and the filter itself may be shaped in a
non-cylindrical shape or may be replaced with other devices such a
pleated filter or the like. Such variations will be understood by
persons of ordinary skill in the art.
[0054] After passing through the cyclone outlet 808, the air passes
through a first outlet tube 810, a second outlet tube 812, and a
third outlet tube 814. These separate outlet tubes are connected to
one another by respective gaskets 818, 820, and 822 to help prevent
air from leaking into the working airflow at the tube junctions. In
a preferred embodiment the third outlet tube 814 is positioned in
the dirt cup opening 210, and can be removed by the user if it
becomes clogged. To help assess whether a clog exists, the third
tube 814 also may be made from a transparent material. It will be
understood that the foregoing arrangement of three tubes is
exemplary, and the multiple outlet tube shown herein may be
consolidated into a single tube, into two tubes or into various
other numbers of tubes.
[0055] As best shown in FIG. 9, the third outlet tube 814 is
fluidly connected with the recess 214 into which the pre-motor
filter 212 is installed, and the airflow passes from the third tube
814, through the pre-motor filter chamber inlet 238, and then
through the pre-motor filter 212. Next, the airflow enters through
the vacuum fan 902, and exhausts through the post-motor filter 218
to the atmosphere.
[0056] Referring now to FIGS. 10-12 an exemplary embodiment of a
dirt cup 112 is described in detail. As shown in FIG. 10, the dirt
cup 112 has a generally cup-like structure to which a handle 1002
is attached to facilitate removing and carrying the dirt cup 112.
If desired, the handle 1002 also may be suitable for lifting the
entire vacuum cleaner 100. In the exemplary embodiment, the handle
1002 is provided as a separate part that is attached to a
corresponding opening 1004 located at the front of the dirt cup 112
by ultrasonic bonding, adhesives, or the like. Of course, the
handle 1002 may be omitted or modified in other ways, if
desired.
[0057] The exemplary dirt cup 112 also includes an elevator lock
system 1006. The elevator lock 1006 includes a cam plate 1008 that
is rotatably mounted to the bottom of the dirt cup 112 by a cap
1010. The cap 1010 is affixed to the bottom of the cup 112 by a
screw 1014. When assembled, the cap 1010 passes through a hole 1012
through the center of the cam plate 1008, and is shaped and sized
such that it holds as a cam plate 1008 close to the dirt cup 112,
but allows the cam plate 1008 to rotate through an arc of travel. A
knob 1024 or other gripping surface is provided on the cam plate
1008 to facilitate its rotation. The knob 1024 is positioned in a
slot 1022 on the lower end of the dirt cup 112 to limit the cam
plate's range of movement, but other blocking members may be used
to control the cam plate's range of movement, if desired. Such
other mechanisms will be readily appreciated by persons of ordinary
skill in the art in view of the present disclosure.
[0058] The cap 1010 is also shaped and sized to allow the cam plate
1008 to move vertically with respect to the bottom of the dirt cup
112. A spring 1015 may be positioned between the cap 1010 and the
cam plate 1008 to bias the cam plate 1008 upwards towards the dirt
cup 1012.
[0059] The exemplary cam plate 1008 has one or more ramp-like cam
surfaces 1016 on its upper surface. These cam surfaces 1016 are
arranged in a pattern around the circumference of the cam plate
1008 and positioned to engage corresponding protrusions 1102
extending from the bottom of the dirt cup 112, as best shown in
FIG. 11. As the cam plate 1008 is rotated, the cam surfaces 1016
engage the protrusions 1102 to move the cam plate 1008 away from
the bottom of the dirt cup 112. The operation of the cam plate 1008
is illustrated in FIGS. 13A through 13C. In these three figures,
the cam plate and the protrusions extending from the bottom of the
dirt cup 112 are shown in a panoramic view--that is, they are shown
as they would appear to a person viewing them from the center of
the cam plate 1008. FIG. 13A depicts the cam plate 1008 when it is
arranged with the cam surfaces 1016 disengaged from the protrusions
1102, in which case the cam plate 1008 is biased towards the dirt
cup 112 by the spring 1015, and the overall height of the dirt cup
112 and cam plate 1008 assembly is at a minimum. In this position,
the dirt cup 112 can be freely removed from or inserted into the
opening 210 (FIG. 2). Turning to FIG. 13B, once the dirt cup and
elevator lock are inserted into the opening 210, the cam plate 1008
is rotated, and the cam surfaces 1016 begin to engage the
protrusions 1102 to move the cam plate 1008 away from the dirt cup
112. If desired, the cam surfaces 1016 and/or protrusions 1102 may
be provided with detents or matching surfaces 1302, 1304 that allow
the cam plate 1008 to remain in a partially-extended position. As
shown in FIG. 13C, when the cam plate 1008 is fully rotated, it
continues to move away from the dirt cup 112 until it reaches its
fully rotated position, as shown. In this position, the overall
height of the dirt cup 112 and cam plate 1008 assembly is
maximized, and the dirt cup 112 is pressed against the gasket 824
(FIG. 8) to seal it to the cyclone chamber 802. In addition, if a
trap door 216 is used to contain a pre-motor filter 212, the dirt
cup 112 and cam plate 1008 also may press down on the trap door 116
to help seal the airflow passing through the pre-motor filter
212.
[0060] Locking features may be provided to hold the cam plate 1008
in one or both of the retraced (FIG. 13A) or extended (FIG. 13C)
positions. Resilient tabs, detents, or other devices may be used
for this purpose. In the exemplary embodiment, the cam plate 1008
includes a resilient tab 1018 that extending from its upper
surface, and the dirt cup 112 has two additional protrusions 1104,
1106 extending down from it. As shown in FIGS. 13A and 13C, the
resilient tab 1018 engages one protrusion 1106 when the cam plate
1008 is in the fully retracted position, and the other protrusion
1104 when it is in the fully extended position. Of course, one or
both of these locking features may be removed or modified in other
embodiments.
[0061] It will be understood that the drawings of FIGS. 13A through
13C are schematic representations of the operation of the device.
In this exemplary representation, the protrusions 1102, 1104, 1106
are shown in a serial arrangement, as are the cam surfaces 1016 and
resilient tab 1018. In alternative embodiments, such as the one
shown in FIGS. 10 through 12, the cam surfaces, resilient tab,
and/or the protrusions may be arranged around different
circumferential radii of the cam plate. For example, it can be seen
in the embodiment of FIG. 10 that the cam surfaces 1016 are located
closer to the central rotating axis of the cam plate 1008, whereas
the resilient tab 1018 is located further from the cam plate 1008
axis. Thus, the cam plates, resilient tab, and protrusions can be
arranged either around the same circumferential radius in a serial
pattern, or may be arranged at various locations around the cam
plate 1008 and dirt cup 112. it will also be appreciated that the
rotating cam plate 1008 may be replaced by a linearly-actuated cam,
or other cup elevating and locking devices, and such devices may be
mounted on the dirt cup 112, as shown, or on the rear housing
104.
[0062] Referring now to FIG. 14, an embodiment of a base 102 that
may be used with the present invention is described. The exemplary
base 102 comprises a lower base frame 1402 to which an upper base
frame 1404 is removably attached. When attached, the lower and
upper base frames 1402, 1404 form an enclosure that retains and
supports the working parts of the base 102. It will be understood
that any suitable alternative construction for the base may be used
in other embodiments.
[0063] As previously noted, a pair of wheels 106 support the base
102 for movement over the ground. While conventional wheels may be
used in various embodiments, the wheels 106 in the shown exemplary
embodiment comprise hard plastic hubs 106' having resilient
coatings 106''. The resilient coatings 106'' may comprise a
urethane coating having a hardness of about 78 A to 82 A, which is
expected to provide suitable low-slip contact with typical
household surfaces and help absorb shocks that might be transmitted
to the user during use. It is also desirable, but not required, for
the wheels 106 to have a minimum diameter of about 72 millimeters,
and more preferably of about 95 millimeters. Both wheels sizes, but
the latter diameter in particular, are believed to be suitable for
use with upright vacuum cleaners to help the vacuum cleaner roll
over common household obstacles. The wheels 106 are mounted to
conventional stub axles or to a solid wheel axle 1406 by respective
sets of two bearings 1408, and retained by a threaded fastener, a
push nut 1410 or other known devices. A washer 1412 may be provided
inboard of each of the wheels 106 to limit their movement and
prevent interference with the base frames 1402, 1404. The exemplary
washers 1412 slide over the axle 1406 or stub axles, and engage
protrusions 1414 that limit the movement of the washers and wheels
towards the center of the base 102. A hubcap 1416 may be provided
to cover the push nut 1410, bearings 1408, and axle 1406.
[0064] In the illustrated exemplary embodiment, the wheel axle 1406
comprises a rod that extends wholly or partially across the width
of the base. Both wheels 106 are mounted to the axle. The axle 1406
is bent along its length to form a generally U-shaped structure. It
has been found that this construction allows the rear housing (not
shown in FIG. 14) to pivot downwardly and rearwardly with respect
to the base 102 further than would be possible if the axle 1406
extended straight between the two wheels 106. Referring to FIG. 15,
one embodiment of how the bent axle 1406 can be attached to be base
frame 1402 is shown. Here, the bent axle 1406 is fitted into a
groove that extends along the width of the lower base frame 1402.
The axle 1406 may be retained by snap fitment or additional
fasteners. For example, as shown a retaining plate 1418 is provided
at each end of the axle 1406, and each retaining plate 1418 is
attached to the lower base frame 1402 by a pair of screws 1420.
When assembled, the retaining plates 1418 capture the axle 1406 in
place against the lower base frame 1402. Of course, the axle 1406
may be attached to the upper base frame 1404 and/or other parts of
the base, if desired, and other variations may be made to the
foregoing exemplary embodiment.
[0065] It has been found that using a bent, full-width axle (that
is, an axle having a bent portion to accommodate the rear housing
movement and to which both wheels are attached) provides an
advantage over conventional stub axles that are used to mount
wheels to vacuum cleaner bases. In particular, the bent axle allows
the rear housing to be made both wider and with less plastic
material because it is no longer necessary to provide a large boss
into which to mount the stub axle. Such large bosses were required
in the prior art because the stub axles were mounted in a
cantilevered arrangement into the sides of the base, and loads
applied to the wheels, particularly impact loads, applied a high
bending moment to the stub axles that would cause them to pull out
of the housing if there was insufficient support. With a bent,
full-width axle, the bending moments are absorbed by the axle
material, rather than the base material, and the vacuum cleaner may
have improved dimensional tolerances and stability.
[0066] Referring back to FIG. 14, the base may also be provided
with an adjustable height wheel carriage 1422. The wheel carriage
1422 is provided on the bottom of the lower base frame 1402, and
mounted by pivots 1424. The wheel carriage 1422 has a pair of front
wheels 1426, that support the front of the base 102. The wheel
carriage 1422 can be adjusted to raise and lower the height of the
base 102 relative to the ground to accommodate vacuuming over
different types of surface, as known in the art. For example, it
may be desirable to raise the base 102 when vacuuming over
long-pile carpets, and lower the base 102 when vacuuming over
relatively short-pile carpets or uncarpeted floors. In the shown
embodiment, this height adjustment is accomplished by using a
rotating cam 1428 that engages a protrusion 1430 that extends from
the upper surface of the wheel carriage. Such rotating cam height
adjustment mechanisms are well known in the art, and this or other
types of height adjusting mechanisms may be used
interchangeably.
[0067] The wheel carriage 1422 also may have with additional
protrusions 1432 that engage the rear housing 104 when the rear
housing 104 is raised to the full upright position. When the rear
housing 104 is fully raised, surfaces on the rear housing 104 press
against the protrusions 1432, thereby pressing down and lowering
the wheel carriage 1422. This is particularly useful in so-called
single-motor vacuum cleaner designs in which the vacuum fan motor
located in the rear housing directly drives a brushroll in the base
by way of a belt. When the protrusions 1432 are pressed down to
lower the carriage 1422 and raise the base 102, it prevents the
brushroll from abrading the carpet when the vacuum cleaner is
operated while it is upright. In other embodiments, other devices,
such as a belt clutch, may be used to prevent the brushroll from
damaging the carpet or floor when the vacuum is tilted to the
upright position. Such alternatives are known in the art.
[0068] The exemplary base 102 also includes a brushroll chamber
1433 located at the front of the base 102 and formed, in the shown
embodiment, by the assembled lower and upper base frames 1402,
1404. The brushroll chamber 1433 is open towards the bottom of the
base 102 through a brushroll slot, as known in the art, and is
fluidly connected to the vacuum source by way of a connecting hose
1434 that extends out the back of the brushroll chamber 1433. A
brushroll, such as those described subsequently herein or others,
is rotatably mounted in the brushroll chamber 1433 and driven by a
motor shaft (not shown) extending through the rear housing 104 by
way of a belt (not shown). If desired, the upper and/or lower
housing 1404, 1402 may include one or more windows 1450 through
which the brushroll may be viewed during operation, and such
windows may be provided with a light to help see the brushroll. In
the shown exemplary embodiment, the windows 1450 are provided at or
near the ends of the brushroll chamber 1433, but such windows 1450
may be located elsewhere. Such windows 1450 may be constructed in
various ways, such as by being pre-molded and inserted into the
mold for the upper base frame to have the upper base frame 1404
molded around the windows 1450 to lock them in place.
[0069] Still referring to FIG. 14, the base 102 may also have a
handle release mechanism 1434. The handle release mechanism 1434 is
pivotally mounted to the base 102, and includes a protrusion 1346
that extends from the mechanism 1434 to engage corresponding
locking protrusions on the rear housing 104, such as the first and
second protrusions 232, 234 shown on the exemplary rear housing in
FIG. 2. In the shown embodiment, the handle release mechanism 1434
is pivotally mounted on one side of the base 102 by a pivot pin
1437, and a return spring 1438 is provided to bias the handle
release mechanism 1434 into the engaged position. This or other
handle release mechanisms may be used in embodiments of the
invention.
[0070] The lower base frame 1402 also comprises structures to
pivotally mount the rear housing. In the shown exemplary
embodiment, these mounting structures comprise a conventional
retainer strap 1440, which mounts to a cylindrical boss located on
one side of the rear housing 104. At the other side, the rear
housing 102 is attached to the lower base frame 1402 by a mounting
plate 1442. The mounting plate 1442 comprises a base plate 1444
that is mounted to the lower base frame 1402 by screws 1446, and an
upwardly extending structure that has a collar 1448 extending from
it. The collar 1448 fits over the cylindrical boss 236 that extends
from the side of the rear housing 102, as seen in FIG. 2. An
embodiment of this construction is described in more detail
subsequently herein.
[0071] Turning now to FIGS. 16 and 17, two embodiments of
brushrolls 1600 are shown. The first embodiment, shown in FIG. 16,
comprises an elongated shaft 1602 to which bristles (not shown) are
attached. An example of a typical bristle pattern is to have two
helical rows of bristles extending at approximately right angles
from the shaft 1602, but other patterns may be used. In the
embodiment of FIG. 16, edge cleaning bristles 1614 are mounted to
each end of the shaft 1602. The edge cleaning bristles 1614 are
arranged in a radial pattern around the shaft 1602, and extend away
from the pulley 1604 at angles of about 45 to 80 degrees relative
to the longitudinal axis of the shaft 1602. These bristles 1614 are
oriented to clean at or near the ends of the brushroll. The edge
cleaning bristles 1614 may also be mounted on a beveled end portion
1616 of the shaft 1602, which may facilitate inserting the bristles
and promote improved wear or cleaning performance.
[0072] The shaft 1602 may be driven by one or both ends, or may be
driven at some point between its ends by a belt (not shown). When a
belt is used to drive the shaft 1602, the shaft 1602 preferably
includes a pulley to receive and be driven by the belt. In some
embodiments, the pulley can be integrally formed with the shaft,
but in the exemplary embodiments, a pulley 1604 is provided as a
separate part that fits over the shaft 1602. In one such
embodiment, the pulley 1604 has a generally circular outer pulley
surface 1604' that is adapted to engage a drive belt or gear, and a
central opening 1604'' passing through the pulley 1604. In the
shown embodiment, the pulley surface 1604' has a crowned profile
suitable for use with flat belts, ribbed belts ("poly-V" belts) and
possibly cogged belts, but other surfaces may be used, such as a
helical or straight gear tooth surface.
[0073] The pulley 1604 can be placed over the shaft 1602 in a
number of ways. For example, the pulley 1604 can be made from two
semi-circular parts that are placed around the shaft 1602 and
attached to one another by snap fitment, fasteners, adhesives, or
other mechanisms. In the shown exemplary embodiment, the pulley
1604 is provided as a ring-shaped cast plastic or metal part and
the shaft 1602 is molded directly into the pulley 1604. In this
embodiment, the pulley 1604 is captured in place at a portion of
the shaft 1602 having a reduced cross-section 1602'. The pulley
1604 may include ribs 1604''' or a non-circular profile that fits
over corresponding slots 1602'' or non-circular profile on the
reduced cross-section portion 1602' of the shaft to prevent the
pulley 1604 from rotating on the shaft 1602. Alternatively, ribs
and slots may be located on the opposite structure. As other
alternatives, or the pulley 1604 may be rotationally fixed to the
shaft 1602 by friction, bonding with the shaft, mechanical
fasteners, welding, axially-extending protrusions, replacing the
single opening 1604'' with multiple separate openings, or by other
mechanism and means.
[0074] An example of a process that may be used to accomplish this
is a two-part molding process in which the pulley 1604 is molded
separately, then placed into an empty brushroll mold, after which
the brushroll material is injected in to the brushroll mold to
conform to the pulley 1604. Using this process, the pulley 1604 can
be captured in place on the brushroll by a portion of the brushroll
that is formed as a continuous single structure--that is, a portion
of the brushroll that does not have to be assembled from multiple
parts to capture the pulley in place. The resulting brushroll has a
pulley 1604 that is structurally interlocked with the shaft 1602,
at least with respect to axial movement, and no fasteners are
needed to position the pulley 1604 on the shaft 1602. In addition,
although no fasteners may be needed to interlock the pulley 1604
with the shaft 1602, a fastener (such as a pin or screw) may be
inserted to pass through the pulley 1604 and shaft 1602 to help
prevent the pulley 1604 from rotating on the shaft 1602. This
latter embodiment would be useful if the pulley 1604 and/or shaft
1602 is provided without ribs or another non-circular profile. Of
course, in this or other embodiments, other additional parts may be
added to the brushroll or pulley after the molding process. While
the foregoing embodiments illustrate the pulley 1604 as being a
continuous surface that extends entirely around the shaft 1602,
this is not strictly required, and one or more slots or grooves may
be formed in the pulley 1604 to allow for stress relief or thermal
expansion or contraction, or for other reasons. Such slots or
grooves may extend all the way to the central opening 1604''.
[0075] This two-part pulley and shaft brushroll construction can
provide several advantages. For example, in many instances a
brushroll is provided with felt seals on either side of the pulley
and belt to prevent dirt and debris from becoming entrapped between
the belt and the pulley. The use of such seals is helpful to
prevent the inclusion of dirt, but the felt seals often rub against
the pulley surface and generate heat by friction. As such, the
pulley must be manufactured from a material that can withstand this
heat without becoming damaged during use, such as a material with a
relatively high melting point. Such materials may be relatively
expensive. As such, the present construction allows the pulley 1604
to be made out of a relatively expensive heat-resistant material
but allows the shaft 1602 to be made out of a relatively
inexpensive material that may have all of the proper properties for
use as a brushroll but may have a relatively low melting point
(e.g., lower than the melting point of the pulley) or otherwise be
unsuitable to withstand the temperature created by the friction
between the felt seals and the pulley.
[0076] Another example of how this construction may be advantageous
is shown in the embodiment of FIG. 17. Here it is shown that the
pulley 1702 is provided as a toothed gear pulley 1702. Such as gear
pulley 1702 might, like the previous embodiment, require high
temperature resistance because it may rub against felt seals during
use. In addition, the gear pulley 1702 may need to made from a
relatively strong material to withstand driving forces. As with the
prior embodiment, the gear pulley 1702 may be constructed from a
relatively expensive material that has the thermal and strength
properties required for its use, but the pulley shaft 1704 may be
constructed out of a relatively less expensive material that may
not satisfy the strength and temperature requirements required at
the location of the pulley. Furthermore, even if there is no
requirement from a heat resistance or strength standpoint to form
the pulley 1702 separately from the shaft 1704, it may still be
economical to form the gear pulley 1702 separately in a
higher-precision molding process to ensure that the teeth are
properly dimensioned to receive the corresponding toothed drive
belt.
[0077] The brushroll 1600 may be mounted to the base in any
suitable way. In the shown exemplary embodiments, the brushroll
1600 is mounted by a bearing 1606 at each end of the shaft 1602.
Each bearing 1606 is mounted on a end cap 1608 by a pin 1609 that
fits in the inner race of the bearing 1606. The end caps 1608 fit
within correspondingly-shaped slots on either side of the brushroll
chamber 1432, as known in the art. The outer races of the bearings
1606 are mounted to the brushroll shaft 1602 by cups 1610, which
are inserted to hollow ends of the shaft 1602 and staked in place
by pins 1612. A felt seal 1611 and/or other seals may be provided
between each end cap 1608 and the brushroll shaft 1602 to help
prevent dirt and other contaminants from contacting the bearings
1606.
[0078] Referring to FIG. 18, an embodiment of another base 1802 is
provided. The base 1802 includes a separate brushroll motor 1804
that can be used to drive a brushroll independently of the
operation of the vacuum motor. Such vacuum cleaner constructions
are typically referred to as two-motor vacuum cleaners. The
brushroll motor 1804 is operated by the main power supply or an
alternative energy source, and may have a motor switch 1806 that
turns the brushroll motor 1804 off when the rear housing is raised
to the upright position. Such a switch 1806 may be provided
adjacent the mounting plate 1442 and be operated by a protrusion
1808 that extends from the rear housing. A reset button 1810 also
may be provided in the power circuit to the brushroll motor 1804 to
operate as a circuit breaker should the brushroll motor 1804 become
locked or overheat during use. In addition, a motor indictor light
1812 may be provided to indicate the status of the brushroll motor
1804 to the operator. The exemplary motor indicating light 1812 is
visible through an opening 1814 through the upper base frame 1404.
Suitable reset buttons 1810, motor switches 1806, and motor
indicator lights 1812 are generally known in the art.
[0079] The exemplary base 1802 is also illustrated having an
alternative mounting structure for the rear housing 102. As shown
in FIGS. 18 and 19, one side of the rear housing 1902 (FIG. 19) is
mounted by a mounting plate 1442, such as the one described
previously herein, or by a conventional strap or clip. The other
side of the rear housing 1902 is mounted by a mounting cap 1816.
The mounting cap 1816 has a cylindrical body 1816' and a pair of
integrally-formed screw bosses 1816''. The cylindrical body 1816'
fits into a corresponding opening 1820 on the base 1802, and the
two bosses 1816'' attach at corresponding mounting posts 1822 on
the base 1802. The mounting cap 1816 pivotally mounts the rear
housing 1902 to the base 1802, and provides a passage 1906 for
electrical wires, vacuum hoses, and/or other devices extending from
the rear housing 1902 to the base 1802. In the shown exemplary
embodiment, the mounting cap 1816 provides a conduit for a vacuum
hose (not shown) extending between the brushroll motor 1804 and the
vacuum fan 1904. This vacuum hose conveys motor dust, such as
carbon dust and other debris that may be generated by the motor,
into the vacuum fan to be cleaned from the air stream. To
facilitate the operation of such a vacuum hose, the motor 1804 may
be covered by a separate motor cover 1818 that seals the motor 1804
except for ventilation slots located through the cover. This helps
direct the airflow across the motor and into the vacuum hose so
that it may be passed through one or more of the vacuum cleaner
filters to be cleaned before being exited to the ambient air. In
addition, electrical cables or wires for the brushroll motor 1804
or other devices in the base 1802 may be passed through the
mounting cap passage 1906. The use of the mounting cap 1816 with a
passage through it helps direct wires, hoses, and other flexible
elements (such as extractor fluid supply lines) from the rear
housing 1902 to the base 1802 in an efficient and safe manner.
[0080] The manner in which the exemplary mounting plate 1442 mounts
the rear housing 1902 to the base 1802 is also shown in FIG. 19.
Here it is shown that the mounting plate 1442 includes a collar
1448 that extends axially into the side of the rear housing 1902 by
a distance X, and slips over a corresponding mounting boss 1908
that is recessed into the side of the rear housing 1902 to
pivotally mount the rear housing 1902. This construction is
facilitated by offsetting the mounting collar base plate 1444, and
thus the mounting screws 1446, axially (distance Y) from the collar
1448. In contrast, conventional mounting straps locate the mounting
screws in the same plane as the strap, and this construction
typically requires the entire rear housing mounting boss to extend
from the side of the rear housing to allow access to the screw or
screws that are used to secure the mounting strap. In addition, the
base plate 1444 and mounting screws 1446 may be radially offset
(distance R) from the collar 1448, which allows the width of the
base to be reduced at the location of the mounting boss 1908. This
feature allows the base to be provided with a more streamlined
appearance, may allow the rear housing 1902 to be made wider
relative to the base 1802, and may contribute to weight
savings.
[0081] The present disclosure describes a number of new, useful and
nonobvious features and/or combinations of features that may be
used alone, with upright vacuum cleaners, canister vacuum cleaners
or other types of cleaning device, or in other ways. The
embodiments described herein are all exemplary, and are not
intended to limit the scope of the inventions in any way. It will
be appreciated that the inventions described herein can be modified
and adapted to different uses, and all such modifications and
adaptations are included in the scope of this disclosure.
* * * * *