Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
Many consider wall-to-wall carpeting to be
' the peak of luxury; housewives love it for the warm
atmosphere it hrings, businessmen value it for the
air o:E corporate dignity it lends their o~ices; but
to those who must clean and maintain it, wall-to-wall ..
carpeting i9 an immense headache. It must be cleaned
in place; the cleaning must be accomplished in a
relatively short time and if the carpet is not kept
! scrupulously clean, its life may be severly shorten-
ed. For these reasons, the carpet cleaning industry
is constantly seeking improved methods and machinery
for cleaning carpets.
.,,
Recently, a radical:ly new approach to c:Lean-
ing carpets has been developed whichl uses a powdered
cleaning composition con-taining a mixture o~ extreme-
ly porous solid part:icles and a solven-t. This new
cleaning composition is described in U. S. Patent
4,013,594 and has proved especially effective in re-
moving soil from carpets. Further, only a short
lnterval is required between application and removal
of the powdered cleaning composition. Using this new
cleaning composition, it has now become possible to
clean wall-to-wall carpets in offices and stores dur-
ing working hours with little disruption of normal
affairs. However, this progress in cleaning composi-
tions has exposed shortcomings in the carpet clean-
iny machines known to the prior art.
When the devices which are known to the prior
art are used with this new powdexed cleaniny composi-
tion, it is Eound that some areas oE the carpet are
cleaned much better than other areas and -that a streak-
ed appearance results. It is theorized that thls streak-
ed appearance is due to the fact that the powder, un-
like a liquid, must be physically moved into in-timate
contact with the fibers to be cleaned; therefore, to
obtain the full benefit of the powdered cleaning com-
position, it is thought to be desirable to provide a
device which is capable oE transmitting a great deal
of eneryy to the carpet in order to bring the powdered
cleaning composition into intimate contact with the
fiber whi]e distributing -this energy uniformly over
the area which is scrubbed. Further, it is desirable
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to provide a device which does not redistribute -the
powder which has been applied to the carpet.
It is therefore an object of this invention
to provide a device which is capable of transmitting
energy to the carpet uniformly while not redistribut-
ing the powder which has been applied to the carpet.
It has been found that ~his object can be accomplished
by providing a device of the type having a scrubber
which rotates about a point which is driven in a
circle wherein the scrubber is pivotably mounted on
a frame and the weight of the device is supported by
the scrubber and two wheels at the rear of the frame.
Means for pressing powdered cleaning compositiGn into
the carpet are mounted on the rotating scrubber.
Brief Description of the Drawings
Figure 1 is a side elevation of the carpet
scrubbing machine.
Figure 2 is a schematic sectional view taken
along section line 2-2 in E~igure 1.
~'igure 3 :is a sectional view taken along line
3~3 in Figure Z.
Figure 4 is a partly cutaway top view of the
carpet scrubbing machine.
Figure S is an enlarged schematic side eleva-
tion of the front of the machine, partly in section,
showing the manner in which powder is dispensed, and
pressed into the powder if the optional press bar is
used.
Flgure 6 is a top schematic view o a rider
brush a~ttached to the main scrubbing elernent for press-
ing powdered cleaning com~osition into the carpet.
E'igure 7 is a view taken along line 7-7 of
Figure 6.
Figure 8 is a top schematic view of a flexible
wiper attached to the main scrubbing element for press-
ing powdered cleaning composition into the carpet.
Figure 9 is a view taken along line 9-9 of
Figure 8.
Figure 10 is a partial front elevation, partly
cutaway, of the carpet scrubbing machine.
Pigure 11 is a schematic bottom view of the
most preferred brush for use with the machine of the
present invention.
E'igure 12 is a view taken along line 12-12 of
Figure 11 showing the lie of the bristles.
Figures 13 through 17 are schematic views of
alternate configurations o~ the brush.
DescriptLon o~ the PreEerred Embodiment
In E'igure 1, housiny 20 is pivotably mounted on
frame 22. Handle 52 is connected to frame 22 and facil-
itates translating the machine across the carpet to be
;~ scrubbed. Vacuum means 54 is mounted on handle 52 and
is connected to housing 20 by fle~ible hose 56. A pow-
der dispenser of the type described in U. S. Patent
4,019,662 is mounted on frame 22. This powder dispen-
ser includes: a powder storage bin 36 supported by
frame 22 above housing 20 near the front of the machine;
ro-tat:incJ reticulated foam cylinder 38 rotatably mounted
within powder storaye bin 36 which presses against fora-
minous discharge area 40 and motor 42 for rotating reti-
culated foam cylinder 38. Door 4A is provided for seal-
ing foraminous discharge area 40 and for sexving as a
ramp to aid in depositing powder in front of the machine
as it translates over the carpet.
Wheels 23 are rotatably mounted at the lower
rear of the frame 22 and partially support the weight
of the machine in operation. The axis about which both
wheels 23 rotate is parallel to the axis about which
housing 20 is free to pivot. This arrangement prevents
the housing from canting and insures that as the machine
is translated over the carpet, the right side of -the
machine will be at the same height as the left side of
the machine, thus promoting easier handling of the ma-
chine and uniform cleaniny across the wid-th of the path
covered by the machine. However, slnce the weiyht o~
the device i~ supported ~y w~leels 23 and scrubber ele-
ment 32 and sinae housing 20 is ree to pivot, carpets
having piles of various lengths are automatically accom-
modated and housing 20 is free to follow the contour of
the carpet. Wheel brushes 62 are mounted on frame 22
adjacent to wheels 23 to prevent accumulation of powder
on wheels 23.
As shown in Eigure 2, motor 24 having output
shaft 26 is mounted vertically within housiny 22.
Eccentric support plate 27 encircles shaft 26 and also
engages the inner race of bearing 28, Advantageously,
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as shown :in Figure 3, coun-terweights 25 may be ~ount-
ed on eccentric support pla-te 27 to compensate for the
unbalanced weight of the scrubber element 32. Slippage
between eccentric support plate 27 and shaft 26 may be
prevented by the inclusion of key 29 as shown in Figure
2. The outer race of bearing 28 is fixed to scrubber
support member 30 upon which scrubber element 32 is
mounted. Scrubber elemen.t 32 has tufts 31 of bristles
34 which engage the carpet to be scrubbed and which to-
gether with wheels 23 support the weight of the machine.
As best shown in Figures 1 and 5, reticulated
foam cylinder 38 is rotatably mounted in powder storage
bin 36 and presses against foraminous discharge area
40 located at the lower front of the powder storage bin
36. Auxiliary motor 42 rotates reticulated foam cylin-
der 38 within powder storage bin 36. Activation of aux-
iliary mo'cor 42 causes powder to be dispensed through
Eoraminous discharge area 40. Storage bin door ~4 is
pivotably mounted on powder storage bin 36 and in c105-
ed position, .it covers foraminous d:ischarge area 40.
Storage bin cover 46 is provided for the top of the
storage bin and both powder storage bin door 44 and
storage bin cover 46 provide moisture tight seals which
retard the drying out of the powder stored within powder
: 25 storage bin 36. In the open position, as shown in
tdotted lines in Figure 5, storage bin door 44 serves
as a ramp and aids in depositing powder i.n front of the
machine as it translates over the carpet.
On many carpets, there is a tendency for
brushes to redis-tribu-te the powder on the carpet.
This effect is especially pronounced on low level
loop carpets. It is thought that this redistribution
of cleaning powder leads to uneven cleaning of the
carpet and that a streaked appearance results there-
from. It i5 possible to reduce this redistribution
by attaching pressing means to scrubber element 32
around its periphery. Such pressing means can in-
clude pressing members such as rider brushes 37a as
shown in Figures 6 and 7 or flexible wipers 37b as
shown in Figures 8 and 9.
In the more preferred embodiments, as shown in
Figures 10 through 16, tufts 31 of bristles 34 loca-
ted in protruding areas 33 at the outer periphery of
scrubber element 32 will function to press the powder-
ed cleaning composition into the pile of the carpet
and to minimize redistribution of powdered cleaning
composition by scrubber element 32.
As shown in Figure 11~ the region of the lower
face of the preferred brush 32 to which bristles 34
are applied has several protruding areas 33 around
its periphery. Following the periphery of the bristl-
ed area from each protrusion 33 in the direction of
rotation indicated by the arrow, it can be seen that
the distance from the center of the brush to the
outer edge of the bristled area decreases steadily until
the next protrusion 33 i5 encountered. As best shown
in Fi~ure 12, the bristles are slanted at an angle of
~bout 25 from -the ver~ical but as can be seen in
Fiyure 2 are substantially perpendicular to the radi
a] lines extending from the center of the brush. By
applying bristles 34 to the lower face of brush 3Z
as described, it is possible to minimize the tenden-
cy of the brush to redistribute the powder which has
previously been laid down on the carpet.
In operation as brush 3Z orbits and rotates,
tufts 31 in protrudin~ area 33 will encounter parti-
cles which have been laid down on the carpet. Since
the veIocity of tufts 31 in each of protrudin~ areas
33 which first encounter the particles of cleaning
powder is approximately perpendicular to the edge of
each bristled area, the tendency of tufts 31 to ride
up over the particles and to press them down into the
pile of the carpet is enhanced. In contrast when a
circular brush is used/ the velocity of the tuEts
which first encounter the particles of cleaning pow-
der is substantially parallel to the ed~e oE the
2Q bristled area. It is thought that this increases the
tendency O:e the bristles to redistribute the powder.
Bristles 34 are inclined for two reasons.
First, they facilitate the rotation of scrubber eLe-
ment 32 and the proper inclination makes it easier
~or protruding sections 33 to ride up over the pow-
der and work them into the carpet. I motor 24 drives
shaft 26 in the clockwise direction when viewed from
the top, then bristles 34 should lean to the left
when viewed from -the front of the machine. However,
if th~ opposite inclincltion i5 used, satisfactory
results can be obtained but the device will be more
dificul-t to control.
While the shape shown in Figure 11 is the most
s preferred shape for the bristled area, other shapes
such as those shown in Figures 13 through 17 are also
quite suitable. Flgure 13 shows the shape of the
- bristled region on a brush having a gear shaped bris-
tled region. Figure 14 shows the shape of the bris-
tled region on a brush having a cross shaped bristled
region. Figure 15 shows the shape of the bristled
region on a brush having a fan blade shaped bristled
region. Figure 16 shows the shape of the bristled
region on a brush having a saw blade shaped bristled
region. Figure 17 shows the shape of the bristled
region on a brush having an obl,ong shaped bristled
region. Figure 16 differs from Figure 11 principally
in that there are five protrusions in Figure 11 and
six protrusions in Figure 16. I'he shapes shown in
Figures 11 and 16 are preEerred because the presence
of a plurality unobstructed tufts 35 located along a
radial line at the edges of protrusions 33. Each
unobstructed tuft is located so that an imaginary
tangential line segment can be constructed which pass-
es through the center of the tuft and meets the fol-
lowing conditions: the line segment is perpendicular
to an imaginary radial line drawn through the c~nter
of the scrubber element to the center of the tu~t, it
extends in the direction of rotation of th~e scrubber
_g_.
element; it lies within the face of the scrubber
elernen-t and it does not pass throug~ any portion of
any o-ther tuft or between any two other tuf-ts which
are adjacent to each other. Since the brushes shown
in Fiyures 11 and 16 have a plurality of unobstructed
bristles lying on a radial line, they are the most
preferred embodiment of the invention, but other
embodiments in which there are a plurality of un-
obstructed bristles which do not lie on the same
radial line are acceptable.
By shaping the bristled region such that there
are a number of unobstructed bristles, it is possible
to reduce the tendency of the brush to redistribute
powder. In the most preferred configuration, the un-
obstructed bristles will lie on a substantially radial
line. By this combination of scrubber shape and bris-
tle orientation, it i5 possible to minimize the ten-
dency of the brush to redistribute the powder which
has been laid down on the carpet.
In order to further minimize redistribution of
powder, press bar 48 may be plvotably mounted on frame
22 by means of rods 50. As best shown in Figures 4,
5 and lO,,each rod 50 terminates in a flattened por-
tion 51 and tabs 49 are attached to each end of press
bar 48. Each flattned portion 51 is pivotably con-
nected to the corresponding tab portion 49 and each
rod 50 is pivotably connected to frame 22 so that
press bar 48 is free to follow the contour of the
carpet. If press bar 48 is included, storage'bin
door 44 should be of sufficient lenyth to insure that
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the powder will be deposited :in t.ront o pre~s bar
48. In!operation, as the scrubber i5 advanced over
the carpet, powder will be dispensed in front of
press bar 48 which minimizes redis-tribution of powder
by pressing the powder into the pile of the carpet.
Press bar 48 thus tends -to immobilize the powder
and may advantageously be included when use of the
irregularly shaped brush is insufficient to reduce
streaking to acceptable levels.
OPEP~ION
Upon activation of motor 24, shaft 26 is rota-
ted. Since shaft 26 is fixed to eccentric support
plate 27, the center of scrubber element 32 is driven
in a circle. Since scrubber element 32 is free to
rotate about its center it does no-t rotate at the
same speed as shaft 26 but rather ro-ta-tes more slowly.
For example, in the most preferred embodimen-t, motor
24 will drive shaft 26 at 3400 rpm, scrubber element
32 will usually rotate at between 50 and 100 xpm de--
pending upon the type of bristles used and on the
type of carpet being scrubbed.
Upon activation of auxiliary motor 42, reti-
culated foam cylinder 38 is rotated. Particles of
cleaning powder enter the pores of reticulated foam
cylinder 38, are transported into contact with fora-
minous discharge area 40 where they are discharged
onto storage bin door 44 which serves as a ramp and
causes them to be deposited in Eront of housing 20.
:r~ pre~s; bar 48 is i.rlcludecl, the part:ia:le~ of
cleaninc~ powder are pushed .into the pile of the ruy
by press bar 48 as the machine is translated over the
carpet.
Whether or not press bar 48 ls used, tuf-ts 31
in the protrudincJ areas 33 of scrubber element 32
encounter the particles of cleanin~ powder heore the
other tufts on scrubber element 32 and aid in press-
ing the powder down into the carpet. The remaining
tufts 31 scrub the powder into the carpet. Vacuum
means 54 prevents excessive dust from escaping from
under housing 20.
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