U.S. patent number 3,823,516 [Application Number 05/316,447] was granted by the patent office on 1974-07-16 for motion imparting member incorporating holding means for nonwoven fibrous abrasive pads.
This patent grant is currently assigned to Norton Company. Invention is credited to Warren E. Christian.
United States Patent |
3,823,516 |
Christian |
July 16, 1974 |
MOTION IMPARTING MEMBER INCORPORATING HOLDING MEANS FOR NONWOVEN
FIBROUS ABRASIVE PADS
Abstract
Surface finishing means comprising nonwoven fibrous material is
held firmly but removably on a member capable of imparting motion
to the finishing means by a plurality of discrete, spaced-apart
holding means located in the surface of the motion imparting member
comprising a plurality of hook-like members on a base member.
Inventors: |
Christian; Warren E. (Troy,
NY) |
Assignee: |
Norton Company (Troy,
NY)
|
Family
ID: |
26785732 |
Appl.
No.: |
05/316,447 |
Filed: |
December 19, 1972 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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92485 |
Nov 24, 1970 |
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Current U.S.
Class: |
451/490; 15/98;
15/230.17 |
Current CPC
Class: |
B24D
9/085 (20130101) |
Current International
Class: |
B24D
9/00 (20060101); B24D 9/08 (20060101); B24d
017/00 (); B24d 013/14 () |
Field of
Search: |
;51/358,388,17T,177
;15/230.12,230.14,230.16,230.17,230.19,406 ;24/204 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Simpson; Othell M.
Attorney, Agent or Firm: Gatewood; Herbert L.
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of application Ser. No.
92,485 filed Nov. 24, 1970, now abandoned.
Claims
What I claim is:
1. Motion imparting member suitable for imparting a desired motion
to and satisfactorily holding a surface finishing means comprising
a nonwoven fibrous pad, said motion imparting member comprising a
driving face comprising a drive face, a plurality of spaced apart
recesses in said drive face, and located in each of said recesses a
holding means comprising a base member having projecting outwardly
therefrom a plurality of hook-like members, said hook-like members
extending sufficiently from each said recess so that means are
provided for interlocking engagement with said nonwoven fibrous pad
for accomplishing the desired holding action, said holding means
further comprising means on said base member providing for
removable engagement of said holding means with the drive face of
said motion imparting member.
2. Motion imparting member according to claim 1 for combination
with the drive member of a floor machine for imparting a desired
motion to a fibrous floor pad, said driving face comprising a
resilient member.
3. Motion imparting member according to claim 2 wherein said
driving face comprises a first resilient layer having a front side
and a back side, and adhesively secured to said front side a second
resilient layer, said recesses being provided in at least said
second resilient layer.
4. Motion imparting member according to claim 2 wherein said
driving face includes in combination with said resilient member a
relatively rigid backing member.
5. Motion imparting member according to claim 2 wherein said motion
imparting member comprises in combination with the driving face a
body member adapted to be secured to the drive member of said floor
machine.
6. Motion imparting member according to claim 1 wherein said
driving face comprises a suitable plastic material.
7. Motion imparting member according to claim 6 wherein said
plastic material comprises polyvinyl chloride.
8. Motion imparting member according to claim 1 wherein the driving
face is characterized by high frictional characteristics thereby
providing for, in combination with the holding means, more positive
movement of the nonwoven fibrous finishing means.
9. Motion imparting member for imparting a desired motion to and
holding a surface finishing means comprising a nonwoven fibrous pad
wherein a driving face is integral with a driven body member so as
to provide a motion imparting member of unitary construction and
entirely of some suitable plastic material, said driving face being
provided with a surface having high frictional characteristics, a
plurality of spaced apart recesses extending inwardly in the drive
face of said driving face and located in each of said recesses a
holding means comprising hook-like members, said hook-like members
extending from said recesses whereby means are provided for
interlocking engagement with said fibrous pad and where, in
combination, the holding means and high frictional surface provide
more positive drive of the fibrous pad, said holding means further
comprising releasable interengaging means for releasably attaching
said holding means to said drive face.
10. Motion imparting member according to claim 9 wherein said
plastic material is polyvinyl chloride.
11. Motion imparting member according to claim 10 wherein said high
frictional characteristics are provided by a surface having a
rough, non-planar configuration.
12. Motion imparting member according to claim 1 wherein said
motion imparting member is of circular shape and said recesses are
located in at least one annular row located at some desired radial
distance from the center of said motion imparting member and
concentric with said member.
13. Motion imparting member according to claim 12 wherein said
motion imparting member is of annular shape.
14. Motion imparting member according to claim 12 wherein the
recesses are arranged in a plurality of concentric annular rows,
the openings being so located that the holding means in adjacent
rows are staggered with respect to one another.
15. Motion imparting member according to claim 14 wherein a greater
number of holding means are located adjacent the periphery of the
circular shaped motion imparting member than at its more central
portion.
16. Motion imparting member according to claim 1 wherein the base
member of each holding means is circular shaped.
17. Motion imparting member according to claim 16 wherein said
circular shaped base member is approximately 1 inch in
diameter.
18. Motion imparting member according to claim 17 wherein the
hook-like members of the holding means are arranged in parallel
rows.
19. Motion imparting member according to claim 18 wherein the
hook-like members are spaced from one another about one-eighth inch
center-to-center.
20. Motion imparting member according to claim 19 wherein the
hook-like members are substantially T-shaped in cross-section.
21. Motion imparting member according to claim 2 wherein said
resilient member comprises foam rubber.
22. Motion imparting member according to claim 4 wherein the
diameter of the resilient member is greater than that of said
backing member.
23. Motion imparting member according to claim 1 wherein an opening
extends inwardly from each of said recesses and each said holding
means has prong-like means projecting from the back side of its
base member for removable engagement in said opening.
24. Motion imparting member according to claim 23 wherein said
prong-like means engaging each said opening is a split-type
fastener and each said opening is provided with locking means
whereby each holding means is removably secured in the drive
face.
25. Driving face suitable for attachment to a floor machine driven
member which imparts a desired motion to a nonwoven fibrous floor
pad, said driving face having a drive face, a plurality of spaced
apart recesses in said drive face, and located in each of said
recesses a removably engaged holding means comprising a plurality
of hook-like members extending from the front surface of a base
member, each said holding means being recessed in said drive face
so that only the hook-like members extend beyond the plane of the
driving face, said holding means further comprising means providing
removable engagement of the holding means with the motion imparting
member.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to surface finishing apparatus suitable for
the cleaning, polishing, and the like of various substrates and in
particular floors of various materials. Even more specifically, it
relates to the means by which surface finishing means such as
nonwoven fibrous pads are held firmly, yet removably, on a motion
imparting member.
2. Description of the Prior Art
Nonwoven fibrous abrasive material, such as that disclosed in U.S.
Pat. No. 3,020,139, has been used now for a number of years in the
cleaning, polishing, and the like of floors in homes, office
buildings, etc. of materials such as vinyl, asphalt tile, marble,
wood and terrazzo. The fibrous abrasive material for these
applications is provided, in general, in the form of circular or
annular shaped pads, either the so-called "convolute" pad or those
referred to in the trade as "flat" pads.
These nonwoven discs or pads, of man-made fibers such as nylon
fibers, have been found to have certain desirable features,
particularly over those pads manufactured from metal fibers. Quite
advantageously, they are rust-free and therefore result in longer
life. Moreover, because of their open, porous nature, these
nonwoven, fibrous pads can be cleaned easily after use, e.g., by
mere flushing with water, for storage.
Of some importance also is the fact that cleaning and scouring pads
of nonwoven man-made fibers are nonconductive. Because of this
advantageous feature, these pads can be used in applications in
which floor pads of metal fibers are unsuitable. One such
application involves cleaning and scouring areas in which
electronic equipment, e.g., computers, are located.
Notwithstanding the many desirable features of nonwoven fibrous
abrasive pads, such as those above-mentioned, their use has been
attendant with some problems. One problem in particular centers
around the means by which motion is imparted to these nonwoven
fibrous pads and the manner in which the pads are held in contact
with a motion imparting member.
In the early usage of nonwoven, fibrous, abrasive pads, and in
particular floor pads, it readily became evident that it was not
enough to merely impart motion to a floor pad, some means was
desirable to maintain the pad in suitable contact with the motion
imparting member. Out of this desideratum evolved the floor pad
holder disclosed in U.S. Pat. No. 2,995,765, assigned to Norton
Company, assignee of the present invention. Subsequent to this,
other motion imparting members and floor pad holders of various
design and structure followed. Exemplary of this latter prior art
are those pad holders and motion imparting members disclosed in
U.S. Pat. Nos. 3,302,232; 3,436,876; 3,462,889; 3,464,075; and
3,527,001; Canadian Pat. No. 806,890; and British Pat. No.
914,315.
Although the pad holders and drive members now known in the trade
provide, in many instances, reasonably suitable performance, none
of them, to my knowledge, has been found totally satisfactory. In
particular, some of these devices provide suitable driving motion
but do not adequately hold, in fact are not really intended for
this purpose, the fibrous pad on the motion imparting member.
Others provide a holding function, sometimes less than
satisfactory, but impart little, if any, motion to the nonwoven pad
during use. A particular fault found with some pad holders, e.g.,
those used with center-hole floor pads, resides in the fact they
provide, particularly with flat pads, inadequate holding of the
nonwoven fibrous pad on the motion imparting member, particularly
at the periphery or outer edges thereof. This results in, on
tilting or lift-off of a floor machine, what is sometimes called
"peripheral sagging". On occasion, this sagging is followed by
folding over of the floor pad on again commencing operation. The
consequences of this occurring may be a torn and therefore unusable
floor pad.
Of major disadvantage with some pad holders is the inconvenience
resulting in the necessary manual manipulation of locking and
releasing means whenever a pad need be positioned or replaced on a
floor machine. Moreover, the locking or central holding means as
now known are particularly a problem with use of convolute pads. In
many instances, the center convolution, on tightening of the pad
holder is delaminated from the adjacent convolution. Thus, such a
floor pad, before being used at all, may be rendered useless.
A somewhat related problem, i.e., one which can be said to result
from inadequate holding of a floor pad, involves slipping,
particularly where the motion imparting member is the rotatable
type, between the motion imparting member and the floor pad. Where
this occurs, the motion imparting member and floor pad rather than
acting in unison as desired, act independently of one another. The
result, again, may be a torn and therefore unusable floor pad.
While the above-mentioned problems and disadvantages have been at
least somewhat alleviated in the provision heretofore of hook-like
means or pile-like surfaces on the motion imparting member, the
obtaining of desirable, tenacious holding of the surface finishing
means on the drive member at all times still remains a problem.
SUMMARY OF THE INVENTION
The present invention, in its basic aspects, involves a motion
imparting member comprising a novel driving face for nonwoven
fibrous abrasive pads in which a plurality of discrete,
spaced-apart holding means are located in recesses in the drive
face, each holding means comprising a plurality of spaced-apart
hook-like members or elements. These hook-like members, on the
fibrous pad being placed in contact with the motion imparting
means, engage with the entangled fibers of the nonwoven fibrous
pad, and thereby mechanically, yet releasably, secure the fibrous
pad to the driving face of the motion imparting member.
Quite advantageously, in the preferred embodiment of the invention,
the discrete holding means are adapted for removable engagement
with the motion imparting member whereby, when worn-out or the
like, each holding means can be removed and replaced with another
holding means. Thus, a motion imparting member can be restored to
like new condition with a minimum of expense and effort.
With the motion imparting member of my invention, nonwoven fibrous
floor pads are held securely, even during use at relatively high
centrifugal speeds, without slippage or peripheral sagging. Floor
pads can readily and easily be placed on and removed from the
motion imparting member without need for any manipulation of
turn-buttons, wing nuts or other mechanical locking or releasing
means.
BRIEF DESCRIPTION OF THE DRAWING
Understanding of the invention will be facilitated by referring to
the accompanying drawing in conjunction with reading of the
specification in which like numbers refer to like parts in the
various views, and in which:
FIG. 1 is a side view illustrating a floor polishing machine in
combination with a motion imparting member in accordance with the
invention which drives, in rotary fashion, a circular shaped floor
pad for polishing a floor;
FIG. 2 is a side view of the motion imparting member shown in FIG.
1;
FIG. 3 is a plan view of the motion imparting member shown in FIG.
2 looking at the drive face;
FIG. 4 is an exploded view of the motion imparting member shown in
FIG. 2 showing its major components and their relationship with one
another as well as one means of joining them together;
FIG. 5 is a greatly enlarged view of a portion of the driving face
of the motion imparting member shown in FIG. 4, in cross-section
taken on lines 5--5, showing in detail the removable engagement of
a discrete holding means, in accordance with the invention, for a
nonwoven fibrous pad;
FIG. 6 is a greatly enlarged view in perspective of the discrete
holding means shown in FIG. 5;
FIG. 7 is a greatly enlarged view of another hook-like member which
will be found suitable in the practice of the invention;
FIG. 8 is a view in cross-section of a portion of another
embodiment of a driving face in accordance with the invention
showing the removable engagement of a holding means;
FIG. 9 is a view in cross-section of a portion of a solid plastic
driving face similar to that shown in FIG. 8 except that its front
surface is rough and irregular;
FIG. 10 is a plan view showing a portion of the irregular surface
of the driving face of FIG. 9;
FIG. 11 is a view in cross-section of a motion imparting member in
accordance with the invention showing in unitary construction a
body member and driving face; and
FIG. 12 is a view in cross-section of still another embodiment of
the invention showing a motion imparting member of unitary
construction.
DETAILED DESCRIPTION OF THE INVENTION
Turning now to the drawing, there is shown in FIG. 1 thereof a
motor driven floor machine 10 conventionally used in the cleaning
and polishing of floors 11. Attached to the drive means (not shown)
of floor machine 10 is a motion imparting member 12 comprising body
member 13 and drive face 14 for imparting, in this case, a rotary
motion to a nonwoven fibrous abrasive floor pad 15. It will be
appreciated that motion imparting member 12 may impart to or drive
floor pad 15 in a rotary motion or otherwise, depending upon the
particular floor machine 10 being used; however, for purposes of
more specifically describing the invention herein, a motion
imparting member imparting a rotary motion will be disclosed more
particularly hereinafter.
Motion imparting member 12, in the drawing, is seen to be annular
shaped, having a central portion 16 thereof cut out; however, the
motion imparting member may be either annular or disc-shaped, as
desired. In fact, some motion imparting members, depending on the
particular floor machine, will not have their center cut out.
Similarly, the floor pads used in the invention may or may not, as
desired, have a center hole.
In a preferred embodiment of the invention, motion imparting member
12, as seen more clearly in FIG. 4 of the drawing, comprises a
drive face 14 incorporated in a driving face 17 which is separate
and distinct from drive block or body member 13. Driving face 17,
depending on the particular material from which it is manufactured,
will optionally include on the back side a backing member 18 which
is adhesively or otherwise secured to the driving face. The driving
face may be secured to body member 13 by means of, for example,
machine screws 19 or the like. A clutch or coupling means 20 is
attached to the back side of body member 13 by means of wood screws
21 or the like fastening means for attaching the motion imparting
member 12 to the drive means of floor machine 10.
The driving face 17 can be of resilient material or otherwise, as
desired. Where of resilient material such as a layer of foam rubber
or the like, e.g., polyvinyl chloride or polyurethane foam, or a
resilient nonwoven fibrous layer, a cushioning or vibration
absorbing effect may be provided. Moreover, a driving face of
resilient material may be found to permit greater conformity to
irregularities in the floor or the like being cleaned. Such a
driving face should be relatively firm, yet readily compressible,
and be about three-eighths inches thick. However, it is believed
quite obvious, the thickness and firmness of a satisfactory
resilient driving face in any particular instance will depend to
some extent on the floor machine being used.
The resilient driving face may be entirely of one resilient
material or made up of a plurality of layers each of which provides
a different function. The driving face comprises, in one embodiment
of the invention, and as shown more clearly in FIG. 5 of the
drawing, a first or inner, relatively soft, resilient layer 22 and
a second or outer layer 23 of the same or similar resilient
material, the purpose for which will be hereinafter explained.
In the case of a resilient driving face, a backing member 18 of
relatively stiff material is, in general, provided in combination
therewith. The backing member can be of various materials such as
wood, metal, plastic and the like. A composition hardboard such as
"Masonite" or a high pressure laminated plastic sheet such as that
sold under the trademark "Formica" is preferred.
The resilient driving face is desirably of slightly greater overall
diameter, e.g., about one-half inch, than backing member 18 which
may or may not, as desired, be of greater diameter than body member
13. This will provide, in effect, a resilient bumper and prevent
scratching or otherwise marring of furniture or walls with which
backing member 18 might otherwise come in contact. To inhibit
tearing of the resilient driving face, particularly where the face
is a layer of foam rubber or the like, it has been found desirable
to provide such a layer with a peripheral surface having tear
resisting characteristics. One way to accomplish this feature is to
provide a circular shaped foam layer in which the periphery is of
greater density, than its more central portion. However, such a
feature can also be obtained, quite simply, by applying to the
periphery of the resilient drive face a layer of polyvinyl chloride
or the like pressure-sensitive adhesive tape. This tape is easily
applied by hand to the peripheral surface of the resilient layer
and, on release after being applied, tends to recover or shrink
thus readily conforming to the resilient drive face periphery.
As before disclosed, driving face 17 need not be resilient or
incorporate a backing member. The driving face can be of a
relatively rigid construction such as is provided in a molded layer
of plastic material such as polyvinyl chloride, polyamide,
polyacetal, polycarbonate, acrylonitrile-butadiene-styrene (ABS)
resins and the like. Such a driving face is shown in FIGS. 8 and 9
of the drawing. Where driving face 17 is of a relatively rigid
material, as before disclosed, a backing member is found
unnecessary and the rigid driving face can be secured directly to
drive block or body member 13. This can, of course, be accomplished
by conventional screw means known to those in the art.
The rigid drive face will, in general, be of slightly larger
diameter than body member 13 and can be provided on its outer
circular periphery with a bumper 24, as shown in FIG. 9 of the
drawing. The bumper can be of any suitable resilient material such
as foam rubber or the like and can be adhesively secured or not, as
desired, to the driving face periphery. Thus, the marking of
furniture, walls and the like will be avoided if, by accident, they
are bumped by the driving face.
The front side or surface of driving face 17, i.e., the drive face
14, can be provided, if desired, with a surface exhibiting high
frictional characteristics. Such a surface may be more or less
desired depending on the material of the driving face and its
particular frictional properties. It may be unnecessary where the
driving face is of resilient material such as foam rubber or the
like. On the other hand, with relatively stiff, hard, resinous
material a high friction surface may be found desirable. One such
high friction surface 25 is shown in FIG. 9 wherein the drive face
surface takes the form of downwardly extending pyramid-shaped
projections 26 which are either cut into the molded drive face
surface or are provided therein during the molding operation.
However, a surface exhibiting somewhat higher frictional
characteristics will result from any roughened surface and it need
not take this particular configuration. If desired, a high friction
coating material can be provided on the drive face.
Regardless of which driving face 17 is used in the practice of the
invention, it is, in general, combined with a drive block or body
member 13 such as is shown in FIG. 4 of the drawing. The body
member can be of various materials such as wood, metal, plastic and
resins with or without fillers. One suitable material is a
composition of melamine formaldehyde resin and a filler of wood
chips. Such a composition is readily and easily molded into any
particular shape and is both waterproof and stable under the
conditions to which it is subjected in the cleaning and scrubbing
of floors. In an alternative embodiment of the invention, body
member 13, rather than being of an annular shaped moulded resin
composition, can be a metal disc on the back side of which is
suitably centered and fastened a conventionally used coupling
means. The particular body member, as well as the configuration of
the driving face used, will, of course depend somewhat on the
specific floor machine used.
The drive face 14 is provided with a plurality of discrete holding
means 27 (FIG. 3) located in a spaced-apart, radial relationship,
as shown in FIG. 3, for holding the fibrous pad 15 on, and in
contact with, motion imparting member 12. These holding means, as
hereinafter will be made more clear, are, in the most preferred
embodiment of the invention, desirably mechanically, removably
engaged with driving face 17. This feature is of great advantage in
that it will permit cheap, easy replacement of worn-out or
otherwise unsuitable holding means with others that are
satisfactory. Quite obviously, discrete holding means 27 may be
secured, removably or otherwise, to motion imparting member 12 by
various mechanical means. These include, for example, friction
engaging fasteners of various sorts, screw means, bayonet fasteners
and the like. Fastening or engaging means other than mechanical
means, making the holding means replaceable, or, for that matter,
more permanently engaged in the drive face, as desired, may also be
used in the practice of the invention. One can select, for example,
a suitable adhesive material to accomplish either objective.
Holding means 27 which I have found meets the requirements of my
invention are shown more clearly in FIGS. 5 and 6 of the drawing
and will now be described with greater particularity. Each holding
means 27 is seen to comprise a base member 28 having extending from
the front surface thereof a plurality of relatively stiff,
hook-like members 29. These hook-like members, on closer
observation, are seen to be essentially T-shaped in cross-section;
however, the cross member of the T, at its extremities, curves
somewhat downwardly toward base member 28 to form two opposite
facing hooks. The configuration of an alternative hook-like member
30 is shown in FIG. 7. Therein, the hook-like member is, contrary
to that shown in FIG. 6, shaped somewhat like an arrow or partially
opened umbrella. The barbs 31, of which there are preferably two or
more, meet in a sharp point thereby making for, in certain
instances, easier penetration into the fibrous pad.
The hook-like members 29 which, as shown in FIG. 5, project
prependicularly outwardly from base member 28, are arranged on the
base member in essentially parallel rows (FIG. 6). However, other
spatial arrangements may also be used so long as the members are
uniformly spaced and a hook-like member density of less than about
150 is maintained. A preferred density is from about 75-115
hook-like members per square inch. However, as few as 50 hook-like
members per square inch may be found satisfactory in certain
instances. Hook-like members 29 must be of sufficient length to
allow for entanglement with the fibers of the nonwoven floor pad
being used. On the other hand, they should not be overly long.
Members which are excessively long compared to their
cross-sectional dimension will be found too resilient to accomplish
the desired purposes. In general, where the hook-like members have
a generally round cross-section, their length should be at least
about 3/32 inches and no more than about 3/16 inches. Holding means
27 in which the spacing between hook-like members 29 is on the
order of about one-eighth inch center to center will be found
suitable. Where the holding means is about 15/16 inches diameter
about 69 hook-like members 29 will be provided for entangling with
and holding the fibrous floor pad.
While it is not inconceivable that with some surface finishing
means and under certain conditions, the nonwoven fibrous abrasive
pads may be held on motion imparting member 12 by a relatively
small number of holding means 27, it is obviously desirable that
the number be sufficient to effectively accomplish the desired
result. This number will, of course, depend on many factors
including the size motion imparting member involved, the particular
fibrous floor pad, and the dimensions of the holding means used.
However, one can readily determine, in a few simple experiments,
with any particular holding means available, the number and
disposition thereof, in accordance with the teachings of this
invention, that will give optimum results. In general, however, the
expected results will be obtained when holding means are located in
radial fashion at least at the outer periphery of the motion
imparting member. For more effective results, it may be desirable
to provide more than one annular row of holding means.
Merely by way of example, I have found that with a 15 inch diameter
member capable of imparting rotary motion to a floor pad, two rows
of holding means (15/16 inches diameter, 60 hook-like members
spaced one-eighth inch center-to-center), arranged annularly and
concentrically on the drive face of the motion imparting member,
provided satisfactory results with a variety of nonwoven fibrous
floor pads. More specifically, the holding means can be arranged in
annular rows having radii of 5 inches and 63/4 inches,
respectively, and in each row the holding means are spaced
30.degree. apart. The holding means in the innermost annular row
are, desirably, staggered with respect to those in the outermost
row.
The holding means, and this is an important aspect of the
invention, are recessed, as shown by reference number 32 e.g., in
FIGS. 5 and 9, in drive face 14 so that the nonwoven fibrous
abrasive floor pad will be in direct and intimate contact with the
entire drive face, particularly during use. Thus, the front surface
of base member 28 and driving face 17 are seen to be in the same
plane. In this way, maximum contact is provided between drive face
14 and the nonwoven fibrous pad which is being driven. The holding
means therefore, while perhaps contributing to the drive motion of
the motion imparting member, are not the sole means for
accomplishing this function. The entire drive face aids in
performing the driving function leaving the holding means primarily
for accomplishing holding of the floor pad.
In the most preferred embodiment of the invention holding means 27
is provided on its back surface with split-type fastening means or
self-locking clip 33 by means of which the holding means is
removably secured to motion imparting member 12, as hereinafter
more fully described, by engagement with locking means 34 or the
like. Split-type fastening means 33 (FIG. 5) comprises, in its
basic aspects, two spaced-apart, resilient, prong-like members 35.
These members, for a reason to be explained hereinafter are tapered
downwardly on their outer surfaces to a recessed shoulder 36.
Facing surfaces 37 of prong-like members 35 slant with respect to
one another, as seen in the drawing, thereby forming a V. Thus,
prong-like members 35 act somewhat like a spring on being squeezed
together and then released. The actual mechanics of such a
fastening means is believed well known and no detailed explanation
is believed required herein. It should suffice to state that on
being inserted in a hold of lesser size, e.g., one of only slightly
larger dimensions than prong-like members 35 in their compressed
condition, these members, on frictionally engaging the periphery of
the hole, will be compressed. One further insertion and on reaching
the recessed shoulders 36, however, the prong-like members 35 will
be no longer engaged by the whole periphery. The result is that
these members then spring-back to their uncompressed state. The
recessed shoulders then engage the hole periphery as shown, for
example in FIG. 5 and provide the locking function.
Although the holding means as above described, can be of unitary
construction, e.g., injection molded, it can also be formed of two
distinct members or parts, e.g., a split-type fastener and
laminated thereto a hook-like member. Such a holding means is
available from American Velcro, Inc., of Manchester, N.H. The
hook-like member comprises a plurality of hook-like members
integral with a base. Regardless of the manner of manufacture,
however, the holding means is suitably of some plastic material
such as nylon, polyethylene, polyacetal resin, poly carbonate and
the like.
The manner of removably attaching holding means 27 in drive face 14
will depend, to some extent, on the particular material of which
the driving face is formed. Nevertheless, and regardless of the
driving face material, an opening 38 must be provided in the
driving face extending centrally from the bottom of each recess 32
when using a holding means incorporating a split-type fastener 33.
Thus, when holding means 27 is properly recessed, the fastener will
intrude into opening 38 and be removably held in drive face 14 as
hereinafter explained.
The recesses 32, as well as the openings 38 cooperating therewith
can be provided in the driving face 17 during the forming operation
or subsequently provided therein by die-cutting, machining or the
like. In the case where driving face 17 comprises resilient
material, one simple, yet satisfactory, means of providing recesses
32 and holes or openings 38 is to provide a resilient driving face
comprising two resilient layers 22, 23 as before-described,
adhesively secured together. The first or inner resilient layer 22
is die-cut to provide the desired number of cylindrical holes or
openings 38 to accomodate the selected number of fastening means.
These holes, which after adhesively securing inner resilient layer
22 to backing member 18 are open at the outermost end, must be of
sufficient depth and of large enough diameter to accommodate
prong-like members 35.
The second or outer layer 23 of the same or similar resilient
material and of the same diameter is die-cut to provide an equal
number of cylindrical holes of substantially larger diameter, e.g.,
large enough to accomodate the base member 28 of holding means 27.
The thickness of this layer should correspond to the depth of
recess desired, taking into account the locking means used, as
hereinafter more fully described.
Each resilient layer is die-cut in the same respective locations so
that when adhesively laminated together the centers of the holes in
each layer will coincide. Thus, recesses 32 are provided in drive
face 14, the bottoms of which, to some extent, are provided by the
front surface of inner resilient layer 22 immediately surrounding
holes or openings 38.
A locking means 34 is provided, as before disclosed, in each recess
32 for holding means 27. This can be accomplished using a
conventional metal washer of suitable annular dimension. Thus, such
a locking means comprising an annular surface 39 and a center hole
40 is centered at the open or outer end of each hole or opening 38
and is secured to the surface of inner resilient layer 22. This
annular shaped locking means must have an outer diameter greater
than the diameter of hole 38 and an inner diameter less than the
diameter of hole 38. While the outer diameter of locking means 34,
in the case of a washer, is of no consequence, except that it in
general forms the actual bottom of recess 32 and is usually of
slightly larger diameter than base member 28, the inner diameter
must be large enough to accommodate prong-like members 35 in their
at least somewhat compressed state. Obviously, the inner diameter
of the locking means must be small enough to compress to some
degree the prong-like members. Thus, it is seen that annular
surface 39 of locking means 34 closes off the outer end of each
hole 38 so as to provide an opening of lesser dimension than hole
38 per se.
Alternatively, the locking means may be provided by die-cutting a
suitable number of holes in a metal plate or the like of the same
diameter as the driving face. These holes and their immediate
peripheral surface, it will be seen, perform the same function as
annular surface 39 and center hole 40 in the before-described
locking means. Such a locking means can be provided, e.g., as an
intermediate layer between inner resilient layer 22 and outer
resilient layer 23 and, of course, is adhesively secured to both
layers.
In the practice of the invention holding means 27 are snapped into
drive face 14 by placing the holding means, with prong-like members
35 inserted in the center hole 40 of the locking means, in contact
with the locking means. On pushing inwardly, the tapered surfaces
of prong-like members 35 are engaged by the periphery of center
hole 40. This causes the prong-like members to be compressed
thereby allowing their further penetration into opening 38. On
reaching recessed shoulders 36, the prong-like members pring back
to their uncompressed state. This is permitted, moreover, by the
larger diameter of hole 38. As a result, recessed shoulders 36
overlap with the inner peripheral surface of the annular locking
means and thereby serve to lock holding means 27 in position and
prevent their inadvertent removal. However, and this is of great
advantage with respect to the invention herein disclosed, holding
means 27 can be removed when worn out or the like and replaced with
a new one. To do this, one need merely insert a finger nail or a
prying tool such as a screw driver or the like under the back
surface of base member 28 and pry the holding means loose from the
drive face.
Where driving face 17 is molded of relatively hard rigid plastic
material, as before-described, the recesses and cooperating opening
may be provided during the molding operation or machined therein
subsequently. Each recess should be of sufficient depth to
accomodate the thickness of the locking means, e.g., a conventional
metal washer, yet provide that the front surface of base member 28
is in the same plane as drive face 14.
In a further embodiment of the invention, motion imparting member
12 may incorporate driving face 17 and body member 13 in a single
unitary construction such as shown in FIG. 11 of the drawing. This
may be accomplished by suitable conventional plastic molding
techniques. The recesses 32 and openings 38 can be provided in the
drive face in the molding operation, as can a roughly configured
surface such as shown in FIG. 10, or these features can be provided
by suitably machining the molded member.
Where light weight is of importance, the motion imparting member
can be provided of a relatively low density material such as a
foamed ABS resin.
A still further embodiment of a motion imparting member in
accordance with the invention is shown in FIG. 12. Therein is shown
such a member similar to that shown in FIG. 11 in which driving
face 17 is provided integral with body member 13. In contrast,
however, to the moulded body member shown in FIG. 11, the body
member in this instance is of more hollow construction. This
provides a more economical motion imparting member while at the
same time providing one of lesser weight. Optionally, a center disc
or closure 41 may be incorporated, if desired, in drive face 14. A
closure can be provided which results in a drive face without a
center opening and may offer advantage where a floor pad is used
having no center hole. The closure being a part of the drive face
may be of the same or different material and may or may not, as
desired, have holding means recessed in its surface.
The inner drive face portion provided by closure means 41 may be
adhesively secured to body member 13 and, in particular, to ribs
42. Thus, the inner and outer portions of the drive face operate in
unison.
To utilize a motion imparting member in accordance with my
invention, such a member is simply attached by means of a coupling
20 to the drive member of a suitable floor maintenance machine,
e.g. the rotatable drive means of a Clarke 15" Floor Scrubbing
Machine. The hook-like members located in the drive face, when the
drive face is placed in pressing engagement with a nonwoven fibrous
floor pad, interengage a plurality of the individual fiber lengths
of the nonwoven fibrous pad. Holding means as described herein have
been found to hold firmly and tenaciously even after more than 360
hours usage to fibrous floor pads and to do so during use without
slippage even though the floor pad is subjected to relatively high
centrifugal force, particularly when wet. Of great significance
also is the fact that these holding means, when disposed in
accordance with my invention, eliminates peripheral sagging on
lift-off and thus the disadvantageous fold-over and tearing of pads
often experienced heretofore with other motion imparting members
and pad holders. Moreover, it has been discovered that convolute
floor pads can be used with the motion imparting member disclosed
herein without attendant delamination of the innermost
convolutions, a problem often experienced with other pad
holders.
When desired, the nonwoven fibrous floor pad can be removed from
the motion imparting member of my invention with a peeling-like
motion much like removing pressure-sensitive adhesive tape from a
surface to which it has been applied. On the other hand, the
hook-like members prevent release of the fibrous pad in a shearing
direction, i.e., at the interface formed between the pad and the
holding means. This feature is particularly advantageous since a
shearing force results from driving the fibrous floor pad, e.g. in
a rotary motion.
The motion imparting member of my invention while described with
some particularity with respect to rotatable drive means can
obviously also be used with other drive means. Some floor machines
provide a sort of oscillating motion rather than a rotary motion
imparting member. In this event, the motion imparting member, as
well as the floor pad, may be square or rectangular shaped rather
than annular shaped as disclosed herein. The motion imparting
member need not even be attached to a mechanical drive means. Such
a member can have a suitable motion imparted thereto manually,
i.e., by hand.
As many different embodiments of my invention will occur to those
skilled in the art, it is to be understood that the specific
embodiments of the invention, as presented herein, are intended by
way of illustration only and not limiting on the invention, but
that the limitations thereon are to be determined only from the
appended claims.
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