U.S. patent number 3,795,932 [Application Number 05/293,993] was granted by the patent office on 1974-03-12 for versatile flow-through foam carpet cleaning apparatus.
This patent grant is currently assigned to Beatrice Foods Co.. Invention is credited to Edward G. Young.
United States Patent |
3,795,932 |
Young |
March 12, 1974 |
VERSATILE FLOW-THROUGH FOAM CARPET CLEANING APPARATUS
Abstract
The versatility of flow-through carpet cleaning is greatly
increased in an apparatus which provides means for passing
foam-generating liquid through a driven surface working pad in
combination with a smooth-faced stiff impervious pressure-plate
positioned in the region below the liquid entry into the pad. The
plate is in direct contact with the carpet. The pressure plate is
smaller than the working pad so that the pad has a revolving margin
between one edge of the plate and the corresponding edge of the
pad.
Inventors: |
Young; Edward G. (Gloucester,
MA) |
Assignee: |
Beatrice Foods Co. (Chicago,
IL)
|
Family
ID: |
23131434 |
Appl.
No.: |
05/293,993 |
Filed: |
October 2, 1972 |
Current U.S.
Class: |
15/98;
15/230 |
Current CPC
Class: |
A47L
11/1625 (20130101); A47L 11/4038 (20130101); A47L
11/408 (20130101) |
Current International
Class: |
A47L
11/00 (20060101); A47L 11/162 (20060101); A47l
011/12 () |
Field of
Search: |
;15/98,5R,320,230 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Roberts; Edward L.
Attorney, Agent or Firm: Lockwood, Dewey, Zickert &
Alex
Claims
I claim:
1. In an apparatus for cleaning carpets and rugs comprising: a
relatively stiff backing member, a surface working pad formed of
open non-woven three-dimensional web material fixed with respect to
said backing member, and a smooth-faced, thin, stiff pressure plate
secured to the lower surface of said surface working pad wherein
the relative dimensioning of the surface working pad and the
pressure plate provides a peripheral margin of the pad around the
pressure plate; the improvement comprising: means for releasing
foam-generating liquid into said surface working pad in a region
axially above said pressure plate.
2. The apparatus of claim 1 wherein said means for releasing
includes means for releasing said liquid in a plurality of said
regions.
3. For use in a surface working machine in which the weight of the
machine is utilized to apply pressure on a surface working element
which is moved by the machine, and in which the machine includes
means for releasing a foam-generating liquid into the surface
working element, the combination wherein the surface working
element includes a pad in combination with a pressure plate; the
pad being an open non-woven three-dimensional surface working pad
positioned to contact a surface to be worked, the pressure plate
being positioned between said pad and said surface, said pressure
plate comprising a relatively thin, stiff, smooth-faced disc having
adhering means for adhering said plate to said pad, said plate
being smaller than the pad to provide a working margin between the
edge of the pad and an edge of said disc, which margin contacts the
material to be cleaned; and wherein said means for releasing
foam-generating liquid into said surface working pad are means for
releasing said surface working liquid only axially above said
pressure plate.
4. In an apparatus for cleaning carpets and rugs comprising a
relatively stiff backing plate, a flexible backing member adhered
to the underside of said backing plate, facing material adhered to
the lower face of said backing member and a surface working pad
formed of an open non-woven three-dimensional web material adhering
to said facing material, said facing material including a multitude
of pad-engaging filaments, thereby providing an exposed face of the
surface edge of surface working pad, a pressure plate including a
thin stiff body portion having an exposed smooth abrasion-free
face, and having attaching means including a multitude of
pad-engaging filaments for releasably connecting said pressure
plate to a portion of the face of the surface working pad; wherein
the dimensions of the surface working pad and the pressure plate
provide a peripheral margin of said pad around the plate; the
improvement comprising: means for releasing foam-generating liquid
into said surface working pad in a region axially above said
pressure plate.
5. In combination:
a driving plate adapted for use on a surface working machine which
has a power transmission adapted to receive said driving plate and
rotate said plate about a substantially vertical axis, said driving
plate comprising means for securing said plate with respect to said
transmission, a flat radially extending element and a plurality of
generally radially extending vanes dividing the upper surface of
said flat element into a series of open-topped compartments, said
vanes being positioned on the bias with respect to radii extending
from said axis, and extending towards the direction of rotation,
each of said compartments having peripheral wall means for
retaining liquid within said compartments, each of said
compartments having downwardly extending discharge opening means
originating adjacent respective vanes and ahead of said vanes with
respect to said direction of rotation, said discharge means being
means through which liquid in each of said compartments can pass
through said driving plate;
means on the lower surface of said driving plate for securing a
surface working pad thereto;
means for channeling said liquid passing through said openings into
said surface working pad at a release zone;
a surface working pad formed of an open non-woven three-dimensional
web material and secured with respect to said driving plate;
a pressure plate including a thin stiff body portion having an
exposed smooth abrasion-free face and having means for releasably
connecting said pressure plate to a portion of the face of the
surface working pad, wherein the dimensions of the surface working
pad and the pressure plate provide a peripheral surface working
margin of said pad around the plate;
said release zone being entirely in a region directly above said
pressure plate whereby liquid released into said zone cannot pass
directly downwardly onto said surface.
Description
This invention relates to innovations and improvements in the use
of rotary surface cleaning machines, and particularly any
flow-through machines.
This invention greatly increases the versatility of flow-through
carpet cleaning. Many proposals have been made regarding foam
cleaning of carpets. For example, it has been proposed that light
surface cleaning of carpets be accomplished with the use of a foam
generated in an aerosol dispensing system. However, this method has
many undesirable features, for example, the discharge of relatively
large amounts of solvents and propellants into the atmosphere, and
the relatively great expense connected with the aerosol can system.
Also, many regard it as most desirable to incorporate dry cleaning
type additives into the carpet or rug cleaning formulation, and it
has been found to be very difficult to incorporate these additives
into an aerosol formulation.
Flow-through carpet cleaning equipment has been available
heretofore, but it has been impractical to attempt light surface
dressing or light scrubbing with such equipment. Only relatively
deep scrubbing with such machines has been practical with
heretofore available equipment. A major advantage of the use of the
flow-through rotary machines, for example, is the great economy of
the operation of such systems since a relatively inexpensive liquid
formulation of foam generating material is applied directly to the
brush and carpet, and a cleansing foam is generated or developed by
the action of the brush and carpet or rug.
Such deep cleaning of carpets involves wetting the carpet to such
an extent that approximately 24 hours or more are required after
each treatment in order to obtain practical drying of the
carpet.
Another shortcoming of the flow-through carpet cleaning apparatus
heretofore available has been the fact that it was possible, and in
heavy scrubbing very likely, that a considerable portion of the
foam-generating liquid would pass directly through the brush into
the carpet being cleaned, rather than being converted into foam
prior to its application into the carpet. This tends to leave a
quantity of un-foamed liquid deep in the carpet or rug, in a
condition in which it is difficult to remove.
It is an object of the present invention to provide an apparatus
which can achieve deep cleaning, but which, moreover, can achieve
light surface dressing in which only a small amount of liquid is
applied, and in which only the upper or outer portion of the carpet
is treated, as a result of which the carpet is dry to a practical
extent in a quarter of an hour or so.
It is another object of the present invention to provide a surface
working apparatus with which light scrubbing can be performed, that
is, the carpet scrubbed and wetted only to such an extent that the
carpet is dry, to a practical extent, within one to 2 hours.
It is another object of the present invention to provide a carpet
cleaning system which has all the economic advantages of the
flow-through carpet cleaning systems, and, moreover, a system which
provides a uniform and controlled application of foam to the carpet
while it is being cleaned.
It is another object of the present invention to provide a
flow-through carpet cleaning apparatus which prevents direct
passage or short-circuiting of foam-generating liquid through the
surface working element into the carpet being cleaned.
These and other objects which will be apparant hereinafter are all
achieved in accordance with the present invention which is
described herein with the aid of specific examples, and with the
aid of the accompanying drawings in which:
FIG. 1 is a perspective view of a rotary flow-through surface
cleaning machine.
FIG. 2 is an exploded perspective view of the driven surface
working element in the machine shown in FIG. 1.
FIG. 3 is a fragmentary cross-sectional view of the lowermost
element of the machine shown in FIG. 1.
FIG. 4 is a top view of the pad support plate shown at the top of
FIG. 2.
Referring now to the figures, a floor machine is generally
indicated by the numeral 10. Floor machine 10 is of the type which
is presently available but is modified in accordance with the
present invention. Machine 10 includes a reservoir 12 for
foam-generating liquid, and an electric power unit, generally
indicated by the numeral 14 for driving a brush block 16 (FIG.
3).
A driving plate sometimes referred to as a driving disc, generally
indicated by the numeral 18, a surface working pad 20, and a glide
disc 22 (FIG. 2) are provided in accordance with the present
invention and these elements are fixed with respect to each other
and are secured to a conventional clutch plate which, in turn, is
secured to a conventional transmission (not shown because
conventional). Although glide discs, surface working pads, and
driving discs have been described heretofore in my previous U.S.
Pat. application Ser. No. 129,896, filed Mar. 31, 1971, and now
U.S. Pat. No. 3,698,032, the glide discs 22, surface working pads
20 and drive discs 18, in accordance with the present invention,
have a unique cooperating structural relationship with machine 10
by which all the objects of the present invention are achieved.
The driving discs 18, in accordance with the present invention,
include a central hub 24 having a flange 26 which is adapted to
receive bolts 28 passing through clutch plate 16 to secure driving
disc 18 to plate 16. At the lower extreme of hub 24, three sets of
elements meet and extend radially outwardly from hub 24: annular,
flat radially outwardly extending flange 30; arcuate vanes 32--32;
and passageways 34--34, which are positioned at the leading edge of
respective vanes 32 and extend generally radially outwardly
parallel to vanes 32 from hub 24. At the periphery of flange 30 and
at the radially outward extreme of vanes 32--32, annular rim 36
extends axially upwardly.
In the illustrated embodiment, there are six vanes 32--32 and six
passageways 34--34.
Rim 36, vanes 32 and hub 24 provide lateral walls for six separated
regions or open topped compartments 37 for which annular flange 30
constitutes the bottom. It will be appreciated from a consideration
of FIGS. 2 and 4 that vanes 32 extend generally radially outwardly,
but curve in a counter-clockwise direction as viewed from above as
shown in FIG. 4. It is further noted that the direction of rotation
of the driving disc, in the illustrated embodiment, is
counter-clockwise, as indicated by the arrows in FIGS. 1 and 4. It
is further noted that the passageways 34 lead the vanes 32 in the
normal direction of travel of driving disc 18. Whenever the driving
mechanism in a particular embodiment drives disc 18 in a clockwise
direction, a different driving disc 18 would be provided since
vanes 32 should curve ahead in the clockwise direction as they
extend radially outwardly, and passageways 34 should be on the
opposite side of the vanes from that illustrated in FIG. 4, namely,
along the leading edge of vanes 32 as they move in the operating
(clockwise) direction.
Driving disc 18 is preferably an integral element cast from metal,
or molded from plastic, but assemblies can be used.
Separate elements which are firmly secured to driving disc 18 are
the circular, impervious, stiff plastic sheet 38 and circular,
flexible element 40, and a plurality of facing pieces 42. Thus,
stiff plastic sheet 38 can be secured to the underside of driving
disc 18 by means of conventional contact adhesive and the flexible
element 40 is adhered to the lower face of sheet 38 by adhesive or
other conventional bonding material. Flexible element 40 provides a
layer of spongy or resilient material of appreciable thickness,
e.g. 3/8 inch to 3/4 inch, and sponge rubber serves very well as
the spongy or resilient layer 40. Other resilient or spongy
materials could be used, such as various foams of standard plastic
materials which are commercially available. Preferably, the exposed
surface of spongy layer 40 offers considerable friction, so that
with the weight of the floor machine on it, layer 40 serves to grip
and help to drive the floor pad 20.
Circular plastic sheet 38 and flexible element 40 are identically
perforated with passageways 34--34 being aligned to provide a
continuous channel from the upper surface of flange 30 through
flange 30, circular plastic sheet 38, and flexible element 40.
To the exposed or lower surface of resilient layer 40, a pattern of
flexible facing material 42 is situated, preferably radially
outwardly of passageways 34. These flexible identical facing pieces
42 are formed so that the exposed surfaces thereof provide a
multitude of projecting tiny resilient surface loops or hook
elements 44. Flexible facing strips, tape or other materials of
this type are commercially available in various forms under the
proprietary name "VELCRO." Various forms of such flexible facing
materials and techniques for producing the same are disclosed in
U.S. Pats. Nos. 2,717,437; 3,009,235; 3,083,737; 3,114,959;
3,138,026; 3,147,528; and 3,154,837. The protruding hooks are
severed loops similar to hooks 44, and are indicated as having a
textile or fabric layer 43 from which the tiny hooks or severed
loops protrude. The hooks or loops are generally arranged in rows
extending transversely across the pieces of tape or facing
materials 42. The loops 44 are generally arranged in a row oriented
in the same direction, each hook being out from the loop. It is
highly desirable that on an overall basis, hooks or loops 44 be
oriented in a plurality of directions. The pieces 42 are suitable
adhered or bonded to flexible layer 40 in a permanent manner.
However, it is not essential that the filament have hooks because
any adhering configuration will be satisfactory for use in
accordance with this invention. For example, a facing material
having extended filaments with knobs or balls at the end thereof
will also serve to penetrate the open pads and to adequately engage
the fibers thereof. Methods of providing knobs or balls at the tips
of such filaments, e.g. as in a brush, are known and some include
melting just the tips of secured filaments to form an integral bead
at the tip of each filament.
The term "multitude" appears in the specification and claims with
respect to the number of pad-engaging filaments. It is to be
understood as signifying a number which is effective to secure or
stick adjacent faces, bonded thereby, to each other with respect to
forces exerted along the plane of the faces during use in carpet
cleaning operations.
Other means can be employed to secure pad 20 to driving disc 18. In
FIG. 3, a single surface working pad 20 is shown held in position
by filament 44 on adhering backing member 42. A co-patent
application (Ser. No. 120,137, filed Mar. 2, 1971) by Edward G.
Young and Howard W. Heggem, which application is assigned to a
common assignee with this application, discloses the use of a
number of working pads 20 stacked in pancake fashion, and such a
stack of pads 20 is eminently satisfactory for use in accordance
with the invention. Pads 20, in the embodiment illustrated herein,
are preferably nylon floor pads formed in uniform, lofty, open,
non-woven, three-dimensional web or bat material, formed of many
inter-laced, randomly extending, flexible, durable, tough,
resilient, bonded nylon fibers. It is to be understood, however,
that pads 20 can be of the type referred to in the early part of
the specification, and can be specifically fabricated to provide
varying degrees of harshness for scrubbing operations.
Single surface working pad 20 is directly adhered to facing
material 40 and is held in place by a loop or hook-shaped filament
44. The tiny loop or hook-shaped or other-shaped adhering filament
penetrates into the open lofty structure of floor pad 20 to serve
to hook under, or otherwise adhere to, one or more of the various
random interlaced fibers or filaments. The action of these
filamentary hooks has been likened to that of a Burdock burr
clinging to fabrics or animal fur or hair. The total force required
to detach or shift a floor pad all at once in an axial direction
from multitudinal hooks provided by facing material 40 or to slide
pad 20 in a direction which is parallel to the face of the facing
material 42 would be considerable. Nonetheless, it is possible to
readily peel a floor pad 20 from one of the driving discs 18 simply
by starting at one edge and gently peeling it therefrom, just as a
piece of adhesive tape is peeled off, or removed from the skin.
In accordance with the preferred embodiment of this invention, a
pressure plate generally indicated at 22 (see FIGS. 2 and 3) is
placed over the middle of the lower face 46 of the surface working
pad 20 as indicated in FIGS. 2 and 3. Pressure plate 22 includes a
relatively thin rigid main body portion 48 having a smooth
non-adhering lower face 50, and a plurality of patches of facing
material 52 permanently adhered to its upper face 54. Patches of
facing material 52 (e.g. "VELCRO" tape) can be substantially
identical to facing material 42 described hereinbefore. In the
illustrated preferred embodiment, facing material 52 is provided in
the form of elongated strips permanently adhering to upper surface
54 of pressure-plate 22, also referred to herein as glide-disc 22.
The action of hooks 56 facing material 52 is substantially
identical to the action of hooks 44 on facing material 52 as
described hereinbefore.
When the terms "upper" and "lower" are used in this specification,
they are intended to refer to the relative position of an element
when machine 10 is in normal operating position, as shown in FIG.
1.
When the term "stiff" is used herein to describe pressure plate 22,
it is intended to mean that plate 22 cannot be bent or folded by
forces encountered in its use. Sheets of tough material which can
be readily deformed are not suitable for use in accordance with
this invention for pressure plate 22. However, plastic disc element
38 need not be as stiff as element 22 in view of the fact that it
is bonded to rigid driving disc 18. The lower surface 50 of
pressure plate 22 is smooth, hard, and non-adhering. Pressure plate
50 can be made of any stiff, smooth, abrasion-resistant material,
e.g. a sheet of vinyl or nylon 1/8 inch thick. Also, this material
is a preferred material for use as a plastic circular element 38.
Composition board, metal, e.g. aluminum, plastics, or other
materials and laminates, can be used to manufacture pressure plate
22 and plate 38, provided the main body of these elements, e.g.
body portion 48 of pressure plate 22, is stiff as defined
herein.
To continue in the description of the cooperative arrangement of
the various elements of the floor machine 10 in accordance with the
present invention, foam-generating fluid is conveyed from reservoir
12 through conduit 60 to release the foam-generating liquid at a
controlled rate onto driving disc 18 (see FIG. 3). The rim 36
prevents liquid from being thrown off upper surface of flange 30
radially due to centrifugal force, and the generally curved
configuration of vanes 32 urge the liquid radially inwardly to
downwardly extending channels 34. It is essential, in accordance
with the present invention, that the channels 34 be situated
entirely axially above pressure plate 22 (see FIG. 3).
Foam-generating liquid is thus discharged through passageways
34--34 into surface working pad 20 in a plurality of regions which
are axially upwards of pressure plate 22. Thus, it is impossible
for foam-generating liquid to pass directly through the open
structure of pad 20 onto a carpet or rug (not shown). When floor
machine 10 is in operation, the surface working pad is subjected to
a great deal of compression, vibrational action, flexing action,
twisting action, and this working of the fibers of the open pad
efficiently converts the foam-generating liquid into a cleansing
foam. The continued generation of foam within surface working pad
22, and the centrifugal forces exerted due to the ration of the pad
20 urges the foam radially outwardly from the region of pressure
plate 22. Also, channels 34--34 serve as air inlets, further
facilitating the generation and radially outward flow of the
cleansing foam. This radially outward flow of foam continuously
flushes the surface working pad 20 to clean it while in
operation.
Thus, instead of foam-generating liquid directly contacting a
carpet, and instead of requiring that the foam-generating liquid be
converted into a foam or otherwise be removed after it is deeply
embedded within the carpet, substantially all of the
foam-generating liquid, in accordance with the present invention,
is first converted into a cleansing foam, and substantially only
the foam is applied in an extremely controlled and uniform manner
to the carpet, and is worked within and into the carpet, in the
form of foam, by the action of the floor machine.
For example, in a preferred use of the floor machine of the present
invention, the machine is moved back and forth transversely of a
general line of a swath being cleaned, while the foam is
automatically generated, applied, and worked in.
In its broadest concept, this invention comprises releasing, while
the floor machine is in operation, foam-generating liquid into a
surface working pad formed of open non-woven three-dimensional web
material at a point above a thin, smooth-faced, stiff pressure
plate adhered to the lower surface of the working pad in
face-to-face relationship, wherein the surface working pad blocks
the passage of the foam-generating liquid though the surface
working pad into the carpet, and wherein the relative dimensions of
the surface working pad and pressure plate leaves a margin of the
pad exposed at the periphery for engaging the carpet or rug
surface.
There are several variables that can be used to get the different
types of adjustment and action. One is the overhang, that is, the
width of the annular margin 62 between the edge 64 of pressure
plate 22 and the edge 66 of surface working pad 20. A second
variable, of course, is the type of pad 20. As indicated above,
pads 20 are available in a variety of thicknesses, and with a
variety of adhesion characteristics. A third variable is the
thickness of pressure plate 22. In this connection, if a thicker
pressure plate 22 is used, it still penetrates slightly into pad 20
(see FIG. 3) forcing a portion of pad 20 around edge 64 of pressure
plate 22 as suggested in FIG. 3. In this connection, it is noted
that, for a given nylon pad, pressure plate 22 penetrates slightly
into the pad 20 the same distance even if pressure plate 22 is
relatively thick. However, when pressure plate 22 is thicker, it
tends to lift the annular margin 62 somewhat off the carpet or rug,
thereby providing a somewhat more gentle action. A fourth variable
is the rate at which the foam-generating liquid is released into
the surface working pad 22. Conventional surface working machines
of the flow-through type have flow-regulating means by which the
relative rate of flow of liquid can be at least approximately
controlled. However, it has been heretofore impossible to uniformly
distribute the foam-generating material in the form of foam, only,
on the carpet. However, in accordance with the present invention,
even though the liquid flow cannot be precisely controlled or
metered by conventional equipment, the relatively crude
flow-control is more than sufficient for controlled uniform
application of foam, as a consequence of the cooperation of the
elements of the present invention, for example, to enable an
operator to perform either light surface dressing, light scrubbing
or deep cleaning with the same operation.
By adjusting the flow-control mechanism (not shown because
conventional) to a relatively low rate, the flow-generating liquid
is discharged through conduit 60 onto all of the regions 37--37,
even though the liquid may tend to surge or pulse from conduit 60.
The fact that the liquid first encounters a relatively large upper
surface of flange 30, and is required to move along the upper
surface of flange 30 to passageways 34--34, virtually eliminates
any pulsing and surging and provides a relatively smooth and even
flow of the liquid through the passageways 34--34, in spite of the
pulsing or surging from conduit 60. Moreover, the foam-generating
liquid is discharged at a plurality of spaced-apart points into
surface working pad 20 (in illustrated embodiment) into six
separated regions.
Under relatively slow-flow conditions, only a small amount of foam
is generated, and the operator can use the surface working machine
10 for the purpose of light surface dressing of carpets, rugs and
the like, in which only the upper or outer portion of the carpet is
treated and in which the carpet is dry, to a practical extent, in a
quarter of an hour or so.
By adjusting the liquid-flow to an increased rate, light scrubbing
can be performed in which the carpet is dry within 1 to 2
hours.
At relatively high foam-generating flow, deep cleaning of the
carpet is practical, and the foam is worked heavily into the carpet
to such an extent that approximately 24 hours or more are required
after the treatment in order to obtain practical drying of the
carpet.
It is also noted that as the janitor works over a wide-ranging
working area with the surface working machine modified in
accordance with the present invention, he can carry one or more
pressure plates 22 with him for instantaneous conversion of the
machine for cleaning carpets. When he encounters a piece of carpet
or rug that needs cleaning, he simply tips the cleaning disc 18 and
pad 20 away from the floor (not shown) and places pressure plate 22
centrally over the exposed surface of pad 20 as shown in FIG. 3.
When the working face 50 of pressure plate 22 and margin 62 of the
pad are lowered to position on carpeting, the driving disc 18 and
the attached element rotate, or otherwise move with disc 18.
The present invention can be used for cleaning any type of carpet
or rug ranging from indoor-outdoor carpets, which are in the nature
of a felt, to shag rugs, etc. When cleaning a badly soiled
indoor-outdoor carpet, it may be necessary to use a relatively more
abrasive floor pad, e.g. the "stripper" type floor pad, and
controlling the amount of foam provides even greater "fine-tuning"
of the operation in accordance with the cleaning requirements.
However, for most carpets or rugs, the floor pad of the "buffer"
type is preferred for use in accordance with the present
invention.
When it is desired that the carpet cleaning apparatus 10 of this
invention be converted back to the conventional surface working
condition, the user merely tips the disc 18 back away from the
floor (not shown) to expose pressure plate 22, and the operator
engages a portion of the edge 64 of pressure plate 22 and peels
pressure plate 22 away from the exposed lowermost surface 46 of the
surface working pad 22. The machine 10 is operated in a similar
manner on a hard surface with pad 20 alone.
Also, although the floor pad 20 in the illustrated embodiment is
circular, and although the equipment described hereinbefore is of
the type which rotates the surface working pad 20, the invention is
not limited to the use of circular pads and circular pressure
plates or to the use of rotating equipment. In general, a pressure
plate 22 will have the same general shape of the surface working
pad 20 to which it is adhered, except that the dimensioning of the
relatively smaller pressure plate is such that a peripheral margin
62 extends beyond pressure plate 22. Thus, surface working pad 20
and pressure plate 22 can be circular, square, rectangular, etc.
However, for use in equipment in which the surface working pad is
rotated, circular pressure plates 22 are preferred. Nonetheless,
for use of square or rectangular surface working pads 20 and
pressure plates 22, in accordance with this invention, oscillating
or vibratory equipment can be employed.
Although a continuous peripheral margin 62 is indicated in the
illustrated embodiment, it is not essential that margin 62 be
continuous in all embodiments of this invention. For example, it is
contemplated that in combinations of this invention which utilize
oscillating or vibrating equipment, and square or rectangular
surface working pads, pads 20 and pressure plate 22 are square or
rectangular. It is contemplated that some embodiments will utilize
rectangular pressure plate 22 which extends completely across a
square or rectangular surface working pad 20 so that a margin 62 is
provided only at the front and rear edges of the surface working
pad. In all preferred embodiments, however, an edge of the pressure
plate 22 will be parallel to its associated edge of pad 20.
Hence, in accordance with the present invention, the versatility of
flow-through surfaces involving machines is greatly increased,
permitting surface dressing, light scrubbing, and deep cleaning
with the same equipment. Moreover, the flooding of liquid through
the surface working element and into the carpet or rug is
substantially eliminated, and the liquid is converted into a
cleansing foam before it is applied to the carpet or rug.
* * * * *