Note: Descriptions are shown in the official language in which they were submitted.
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ROBOTIC SURFACE TREATING DEVICE WITH NON-CIRCULAR HOUSING
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] Not applicable
STATEMENT REGARDING FEDERALLY SPONSORED
RESEARCH/DEVELOPMENT
[0002] Not applicable
BACKGROUND OF THE INVENTION
[0003] It is desirable to minimize the amount of human
labor expended in maintaining and cleaning residential
and commercial spaces. The art has therefore developed
robotic devices that can clean or otherwise maintain or
treat floors, carpeting, lawns or the like without the
necessity for a human to be present during the operation
of the device. The most common robotic devices of this
kind are dusters, buffers, vacuum cleaners, floor
sweepers, other floor polishers, automated mowers and
automated dispensers of agricultural products.
[0004] Such devices typically have a computer control
program to direct a preferred movement pattern. The
control is linked to steering devices as well as motors
that are in turn connected to wheels. Many of these
devices also include sensors to confirm the initial and
later positions of the device relative to the pre-set
path. The most sophisticated of these devices include
sensors to detect the presence of unexpected obstacles,
as well as programming to provide options for altered
paths where that occurs. An example of a prior art
control system for such a robotic system is disclosed in
U.S. Pat. No. 4,119,900.
[0005] Some robotic cleaning devices are generally
circular. However, these tend to leave significant
untreated areas adjacent walls or furniture.
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[0006] Still other devices have a circular front end
and generally linear housing across a trailing end. See
U.S. Pat. Nos. 5,621,291 and 5,646,494. In these devices
brushes for vacuuming a floor are located in the center
of a cleaning robot, between a powerless rear stability
wheel and powered front wheels. The primary cleaning
element is in any event located a distance from the
perimeter or edge of the cleaning robot. Thus, even
though the non-circular portion is the widest portion of
the design, there will still be a space between the
cleaning element and nearby objects such as a wall,
chair, table leg or other obstacle encountered while
cleaning. Such devices therefore do not optimally clean
around these types of surfaces and obstacles, and require
a separate manual operation near them, regardless of the
accuracy of the programming.
[0007] Other autonomous cleaning devices have both a
circular body portion and a non-circular body portion.
They typically position a control and drive system in the
circular portion, and a cleaning device in or on the non-
circular portion. However, the non-circular portion is
made wider than the diameter of the circular portion and
therefore extends significantly horizontally outward from
the sides of the circular robot body to provide a wide
back or trailing end.
[0008] These devices are well suited to clean along
the perimeters of walls. Such devices include those
shown in U.S. Pat. Nos. 5,894,621, 5,998,953, 6,119,057,
and 6,142,252. However, because the trailing end of
these devices is wider than the diameter of the circular
main housing, as the robot turns through a corner or
around furniture the trailing end can become lodged
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between adjacent walls or on a furniture leg if the
device is slightly off its expected path.
[0009] Still other configurations for robotic cleaners
have been developed. See e.g. those described in U.S.
Pat. No. 5,309,592, 5,440,216, and 5,720,077. However,
none adequately addresses all of the concerns expressed
above with. respect to such robotic devices.
[0010] In sum, a need still exists to provide improved
robotic surface treating devices, particularly those that
can effectively clean in and around gaps, irregular
surfaces, angled surfaces and corners, with reduced
tendency to become hung up on encountered surfaces.
SUMMARY ~F THE INVENTION
[0011] The present invention provides a robotic
surface treating device such as a vacuum cleaner, floor
polisher, floor waxer, lawn mower, or dispenser of
agricultural materials. There is a housing having a
leading portion that is rounded along its periphery in
top view and a trailing portion that is non-circular
along at least a portion of its periphery in top view.
[0012] The leading portion houses a control system for
directing movement of the robotic cleaning device, and
the trailing portion is linked to a surface contact
element. The trailing portion has a widest side-to-side
width which is equal to or less than the widest side-to-
side width of the leading portion.
[0013] In preferred forms the device is a duster and
the surface contact element is a dust sheet/dust ruffle
combination where the combination is made of a cleaning
cloth which can be an electrostatic or dust-attractant
material. The dust sheet is positioned so as to contact
a surface being treated by the device when the device is
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moved over the surface, and the ruffle also contacts the
ground when present along the rear and sides of the
trailing portion.
[0014] In other preferred forms the ruffle is
impregnated with at least one of a fragrance, an
insecticide, an insect repellant, a polish, or.a cleaning
fluid, and thus acts to also dispense materials thereby
treating the surface and/or the surrounding environment.
In one form the trailing portion is constructed to
provide pressure on the dust sheet to assist its contact
with a surface to be treated by the device.
[0015] While the duster is a preferred form, the
device might also be selected from the group of vacuum
cleaners, floor polishers, floor waxers, mowers and
dispensers of agricultural chemicals.
[0016] Another form of the invention is a disposable
dust ruffle for use with such devices. The ruffle has an
essentially cup-shaped portion made at least in part of
an electrostatic material, a fastener attached along an
upper rim of the cup, and a skirt made at least in part
of an electrostatic material and extending radially
outward and downward from the upper rim of the cup. The
ruffle may also have the fastener be an elastic band.
[0017] Another aspect of the invention is to provide
methods for using the above devices to clean a surface.
[0028] Because the device has a trailing portion which
is no wider than the leading portion, the device is
resistant to becoming hung up on furniture legs or at
corners. Further, the rounded nature of the front of the
device provides an opportunity for the device to avoid
furniture legs, while the less round nature of the
trailing section insures coverage along walls. Also, the
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electrostatic nature of the skirt insures that the region
between the edge of the contact element (e. g. the rotary
brush) and the housing outer surface will be treated.
[0019] The bottom of the trailing section can be
provided with a plate having a soft cover made of rubber,
foam or other material which expands and contracts
depending on the shape of the surface being cleaned. In
such a case, the contact element can be a sheet of the
electrostatic material in total, or in part. Further,
the skirt can be an additional section of the
electrostatic material.
[0020] The skirt can be a dust-attracting material
sued and dimensioned to be stretch-fit over the trailing
portion of the robotic cleaning device. In such a case,
a rotary brush need not be used and there can be a
central portion and a skirt. The central portion encloses
a bottom surface of the non-circular portion of the robot
to provide a cleaning function on the floor, and the
skirt extends outwardly and downwardly from the periphery
of the trailing portion. The skirt attracts dust and
particulate matter from the surface surrounding the
robotic cleaning device where traditional cleaning
elements do not reach.
[0021] This brief summary of the invention has been
provided so that the general nature of the invention may
be readily understood. However, neither this summary,
nor the attached drawings, nor the description of the
preferred embodiments which follows, should be
constructed to limit the invention. Rather, the claims
should be looked to in order to assess the full scope of
the invention.
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BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 2 is a top plan view of a robotic cleaning
device constructed in accordance with the present
invention;
[0023] FIG. 2 is a bottom plan view thereof;
[0024] FIG. 3 is a partial sectional view taken along
line 3-3 of FIG. 4;
[0025] FIG. 4 is an lower rear perspective view of a
dust cover for use with the present invention; and
[0026] FIG. 5 is a bottom plan view similar to FIG. 2,
but of the device after the FIG. 4 dust cover has been
installed.
[0027] FIG. 6 is a bottom plan view of a robotic
leaning device constructed in accordance with a second
embodiment of the present invention.
[0028] FIG. 7 is a bottom plan view of the robotic
cleaning device of FIG. 1, illustrating a brush cleaning
element.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0029] A robotic cleaning device l0 in the form of a
cleaner or surface treating device is disclosed. It has
a forward, generally circular top view, housing portion
12, and a trailing, generally non-circular top view,
housing portion 14. Portion 12 houses a computer
controller, a motor, a steering mechanism, and linkages
to the drive wheels 30 and 32. Portion 14 is generally
rectangular in shape, with the side-to-side width Y/16 of
the trailing housing portion no greater than with the
side-to-side width X/18 of the front housing portion.
Corners 20 of the non-circular portion 14 may be slightly
rounded such that, in operation, contact with surfaces
such as walls, table legs, chair legs, etc. does not
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result in a dent, scratch or other damage. Although the
robotic cleaning device 10 is shown as having two
separate pieces, it will be apparent that the circular
and non-circular portions can be constructed as a single
piece (See Fig. 6). Furthermore, the non-circular
portion 14 can be constructed to be wider than the
portion 12, and in this configuration a spring mechanism
or other device for retracting the sides of the trailing
portion 14 to provide and to reduce the width when the
device is stuck or otherwise caught in a corner or other
small partially enclosed area.
[0030] A skirt 42 in accordance with. the present
invention is constructed of cleaning cloth which. can
comprise, for example, a dust-attractant material or a
cloth impregnated with a treating material such as a
cleaning fluid or other treating fluid as described
below. The skirt 42 extends around and from the non-
circular portion 14 of the robotic cleaning device.
There can also be a cushioning bumper 24 with. a plurality
of sensors 26.
[0031] In the well known manner the control and drive
system can include programming, circuitry and linkages
for determining a route for the robotic cleaning device
based on a pre-programmed route, as well as providing
feedback loops and corrections based thereon. The wheels
28, 30, and 32 permit the device to roll over most
essentially flat surfaces, with the rear wheels 30 and 32
providing traction and the front wheel 28 being pivotable
to provide steering.
[0032] The non-circular trailing portion 14 comprises
a plate 34 that can be constructed of a heavy material to
provide a selected pressure on the surface to be dusted
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(e. g. it can be made of steel, fiberglass, or another
heavy plastic). To prevent scuffing of some surfaces
(e. g. polished wood floors), there can be a compressible
material 36 such as a foam rubber provided on a bottom
side of the plate 34. The soft facing material 36 is
preferably sized and dimensioned to cover the plate 34,
and may be coupled to the plate 34 with an adhesive or
other material.
[0033] Cleaning cloth 38 is sized and dimensioned to
be stretch-fit over the trailing portion 14. It has a
central sheet 40 sized and dimensioned to enclose facing
material 36, as well as an elongated elastic material 41
surrounding the perimeter of the central sheet 40. There
is also a hanging skirt portion 42 that extends radially
outward from the elongated elastic material 41 to drag
along the floor. Thus, a dusting effect occurs along the
central sheet 40, and any dust kicked up by the movement
of the device tends to be trapped by the trailing skirt
42.
[0034] Moreover, as the skirt is bunched like a dust
ruffle it can wedge into room corners and close to table
legs and pick up dust from those areas even though the
main dusting portion 40 never rides over those areas.
Thus, the device improves the coverage of a dusting
system.
[0035] Although shown to cover only the trailing
portion 14, it will be apparent that the cleaning cloth
38 could cover the entire bottom of the device 10.
[0036] The cleaning cloth 38 is constructed from a
cleaning cloth material, and can comprise an
electrostatic or electret material. Examples of such
materials are those described in WO 02/00819, the
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publication for PCT/US00/20074 filed June 22, 2001. This
disclosure is incorporated herein by reference for a
description of these types of materials. The cleaning
cloth 38 can also provide a treating or dispensation
function. For example, the cleaning cloth can be treated
cleaning fluid or polishes to treat the floor, with
insecticides, insect repellants, and fragrances to be
dispersed to a room, or with a combination of these
treating elements. Furthermore, various sections of the
cleaning cloth 38 can comprise different types of
material, providing, for example, a cleaning section and
a polishing section. Other combinations will be
apparent.
[0037] It should be appreciated that the dust
attractant materials employed in the present invention
will attract dust even when not in contact with them.
This is to be distinguished from a mere adhesive which
preserves contact once made, but does not attract contact
from a distance. Furthermore, the cleaning cloth
material is typically disposable, but can also be a
reusable material which can be cleaned or washed and re-
used.
[0038] As noted above, the cleaning cloth 38 can also
be impregnated with a polish, fragrance, insecticide,
insect repellant cleaning fluid or other material. In
such embodiments the device can provide both a cleaning
function and a treating function. Alternatively, the
cleaning cloth 38 can be designed specifically to
disperse treating elements in the room, as noted above.
[0039] Referring next to FIG. 5, the cleaning cloth 38
is shown installed on the device. The central portion 40
encloses the bottom cleaning surface 35, and the skirt 42
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extends radially from both the right and left sides and
from the back of the non-circular portion 14.
[0040] In operation, as the robotic device 10
traverses a floor or other surface to be cleaned, the
central sheet 40 of the cleaning cloth 38 is applied to
the floor or surface in order to pick up dust and other
particulate matter. The weight of plate 34 of the non-
circular portion 14 applies a pressure on the central
sheet 40 of the cleaning cloth 38. In some applications
(See Fig. 7), the robotic device 10 can also include a
rotary or other brush-driven cleaning element 33. In
this application, particulate matter collected by the
brush can be directed to a location under the cleaning
cloth 38, wherein the cleaning cloth 38 provides an
additional function of collecting particulate matter.
[0041] As the robotic cleaning device 10 turns to the
left or right, the proximity sensors and control system
determine a path which maximizes coverage. For example,
when the circular section approaches a corner the device
may turn to project towards the corner the rectangular
section.
[0042] While a dusting device has been shown, the
principles of the present invention should apply to
vacuum cleaners, floor polishers, lawn mowers, and a wide
variety of other surface treating equipment. Thus,
although specific embodiments of the present invention
have been described in detail, it should be understood
that this description is merely for purposes of
illustration.
[0043] Various modifications of these embodiments may
be made without departing from the spirit or scope of the
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following claims. Thus, the claims should be looked to
in order to assess the full scope of the invention.
INDUSTRIAL APPLICABILITY
[0044] Disclosed are improved robotic surface treating
devices, methods for using them, and dust ruffles for use
therewith.
