U.S. patent number 3,631,869 [Application Number 04/859,882] was granted by the patent office on 1972-01-04 for dental floss holder.
Invention is credited to Rene J. Espinosa.
United States Patent |
3,631,869 |
Espinosa |
January 4, 1972 |
DENTAL FLOSS HOLDER
Abstract
A fork-shaped handle device between whose prongs is positionable
a length of dental floss for use in a person's mouth and a new type
of floss useable with said device.
Inventors: |
Espinosa; Rene J. (La Grange,
IL) |
Family
ID: |
25331961 |
Appl.
No.: |
04/859,882 |
Filed: |
September 22, 1969 |
Current U.S.
Class: |
132/323 |
Current CPC
Class: |
A61C
15/048 (20130101); A61C 15/046 (20130101) |
Current International
Class: |
A61C
15/04 (20060101); A61C 15/00 (20060101); A61c
015/00 () |
Field of
Search: |
;132/91,90,89,92,76.2 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Mancene; Louis G.
Assistant Examiner: McNeill; Gregory E.
Claims
What is claimed is:
1. A dental floss holder, comprising a fork means which includes
transversely spaced-apart elongate prongs defining a generally
U-shaped recess therebetween, free ends on said prongs having means
adapted to contact a length of dental floss extending between said
prongs, said prongs being transversely displaceable relative to
each other so as to tension a length of such floss, said prongs
being transversely displaceable by virtue of said holder being of
resiliently flexible material whereby said prongs are resiliently
flexible relative to each other, said prongs being joined together
to form the base of said U-shaped recess, including a handle
portion extending longitudinally from the base of said U-shaped
recess, a separation extending from said recess along a
longitudinal extent of said handle portion and defining respective
arms on either side of said separation which are resiliently
flexible relative to each other.
2. The holder of claim 1, including a series of holes along the
extent of said separation and a button member slidable along said
separation into either of said holes whereby the degree of flexing
of said arms is variable in accordance with the position of said
button member along the extent of said separation.
3. The holder of claim 1, including a hole at a point along the
extent of said separation between said arms, a button rotatably
mounted in said hole and including cam surface means for engaging
said arms, said cam surface means being adapted to transversely
flex said arms apart pursuant to rotation of said button.
4. The holder of claim 1, including a rotatable member extending
transversely of said arms at a point along the extent of said
separation, said member being threadedly engaged with both of said
arms whereby rotation of said member effects a spreading or closing
together of said arms.
5. The holder of claim 1, including hook means for holding a
circumferential extent of a floss loop whereby another extent of
such loop may be extended between said prongs.
6. The holder of claim 1, the ends of the prongs including
floss-gripping means whereby a length of floss may be mounted to
extend only between said gripping means.
7. The holder of claim 6, said gripping means comprising tight
slits in the ends of said prongs, said prongs being of a
resiliently flexible material whereby said slits act to pinch a
floss which is inserted therein.
8. The holder of claim 6, the extreme ends of said prongs including
transversely extending coplanar slits linearly aligned with each
other whereby a length of floss may be positioned between said
prongs and through said slits.
9. The holder of claim 8, including a length of floss extending
between said prongs and through said slits, a nub on each end of
said floss abutting against a respective outer side of each of said
prongs in tensioned condition.
10. The holder of claim 9, the spacing between said nubs being
slightly smaller than the relaxed spacing between the outer sides
of said prongs whereby said prongs are in slightly flexed condition
as a result of said floss being positioned as mentioned.
11. The holder of claim 1, said separation including a slot
extending longitudinally along said handle and opening at the base
of said recess.
12. The holder of claim 11, said arms being resiliently flexibly
displaceable towards each other.
13. The holder of claim 11, said arms being resiliently flexibly
displaceable away from each other.
14. The holder of claim 1, said separation including a slot
extending longitudinally along said handle up to a point
longitudinally spaced away from said U-shaped recess, mating
abutment shoulder means on each of said arms between said recess
and said slot, said arms being laterally shiftable relative to each
other to lie in adjacent different planes, said arms being in a
resiliently flexioned state pursuant to said shoulder means being
coplanar and in mating abutment with each other whereby said arms
slide alongside each other to produce the separation therebetween
pursuant to their being laterally shifted as aforementioned.
15. The holder of claim 14, said abutment shoulder means comprising
means to prevent inadvertent lateral shifting of said arms.
16. The holder of claim 15, the last-mentioned means comprising
mating ridges in said shoulder means.
17. The holder of claim 13, including a member for locking said
arms in resiliently flexioned position away from each other.
Description
This invention relates to a new type of dental floss and also to a
floss holder which provides a handle and a fork means for
tensioning a length of floss while it is being used for cleaning
teeth.
It is well known that the interface between adjoining teeth can be
cleaned by running a fine diameter filamentary material called
floss between teeth. Most commonly, a length of the floss is
tensioned between the user's two index fingers after first being
wound around each of said fingers, and the user then must to some
extent insert his fingers into his mouth while using the floss. At
best it is a relatively awkward operation; however, the use of
floss is highly effective for thoroughly removing food particles
from between teeth which it would be impossible to accomplish with
an ordinary toothbrush and the oral hygiene benefits derived from
using floss are so notable that its use is growing in popularity
and is definitely already very widespread.
In order to facilitate the use of floss attempts have been made
over a long span of years to develop a floss holder which would
permit a user to use floss as easily as one uses a common
toothbrush. That is to say, only one hand would be required, and at
that, it would be unnecessary for the person's fingers to be
inserted into his mouth. Further, it should be noted that the
winding of the floss ends around the user's fingers requires a
considerable length of floss which is not itself used in the
cleaning operation. A holder would reduce waste of floss to a
considerable extent.
Dental floss holders per se are well known, such as those disclosed
in U.S. Pat. Nos. 1,316,807; 2,873,749; and 3,236,247; however, the
known holders are relatively cumbersome, complex in structure and
costly to manufacture and, therefore, they have not achieved
commercial success. The state of present-day marketing demands that
such an item be produceable in great quantities and at very low
cost; otherwise, it will not "catch on" and will not be accepted by
the public at large.
It is an object of the present invention to provide a dental floss
holder which is simple and inexpensive to manufacture and simple to
use.
It is a further object of this invention to provide a dental floss
holder which incorporates a floss-tensioning feature.
It is a further object of this invention to provide a dental floss
holder which may be manufactured in one piece.
It is a further object of the invention to provide a floss holder
which may be produced by plastic molding techniques.
It is a further object to provide a floss holder which may employ
either conventional straight floss, loop floss, or a nubbed floss
according to this invention.
It is a further object of this invention to provide a novel nubbed
floss.
Other objects are those which are inherent or obvious in the device
and floss disclosed herein, of which there follows a detailed
description of various embodiments as illustrated in the
accompanying drawings, wherein:
FIG. 1 is an isometric view of a floss holder according to a first
embodiment of this invention;
FIG. 2 illustrates a novel type of floss according to this
invention;
FIG. 3 is an exploded side view of the holder of FIG. 1;
FIG. 4 is a sectional view taken along line 4--4 in FIG. 3:
FIGS. 5 and 7 are respectively a top plan view and a side view of a
floss holder according to a second embodiment of this
invention;
FIG. 6 is a pictorial view of an element of the holder of FIG.
5;
FIGS. 8 and 9 are respectively a top plan view of a third
embodiment of a holder according to this invention and a pictorial
view of an element thereof;
FIG. 10 is a top plan view of a holder according to a fourth
embodiment of this invention;
FIGS. 11 and 12 are respectively a partially sectioned top plan
view and a side view of a holder according to a fifth embodiment of
the invention;
FIG. 13 is a partially sectioned top plan view of a holder
according to a sixth embodiment of the invention;
FIG. 14 is a broken-away side view of the holder of FIG. 13
illustrating a detail thereof;
FIG. 15 is an end view of the holder of FIG. 13;
FIG. 16 is a partial side view of a holder according to a seventh
embodiment of the invention;
FIG. 17 is a top plan view of a holder according to a seventh
embodiment of the invention;
FIGS. 18 and 19 are both sectional views taken along line 19--19 in
FIG. 17 to show respective dispositions of the holder;
FIGS. 20, 21 and 23, respectively, are top plan views of holders
according to three further embodiments of the invention; and,
FIG. 22 is a sectional view taken along line 22--22 in FIG. 21.
Primarily, the novel floss of FIG. 2 differs from conventional
floss simply in that it includes nubs 1 at regularly spaced
intervals of from one-half to 11/2 inches along its length, which
nubs could be realized by any known technique. In any event, the
nubs should be such as to be able to act as gripping means for
placing the floss length therebetween under tension. For this
purpose, the nubs are preferably solid and securely fixed along the
floss length. The nubs should not be unduly large and it is
contemplated that, they in fact, be up to one-sixteenth of an inch
in cross-sectional width or diameter. Various techniques are in
fact known for imparting regularly spaced nubs along the lengthwise
extent of synthetic filaments as part of or following the spinning
thereof. The nubs 1 could constitute drops of hardened material
applied in liquid form to a straight smooth floss. Alternatively,
the nubs 1 could comprise pronounced crimps which have been
mechanically imparted to a normally straight floss fiber or they
could even comprise clips applied to the floss mechanically.
In any event, the nubby floss of FIG. 2 could be marketed in the
form of an uncut length in roll form, for example, and the user
could cut therefrom a piece each time it is to be used.
Alternatively, the nubby floss of FIG. 2 could be sold in precut
lengths. Although the nubby floss of FIG. 2 will be specifically
illustrated herein as being used with a floss holder according to
the invention, it is to be noted that said nubby floss could also
be used by itself in the same manner as conventional smooth floss
is commonly used, the nubs 1 enhancing the cleaning action of the
floss as it is run between adjoining teeth.
With reference to FIGS. 1, 3 and 4, the floss holder according to
the first embodiment comprises a handle portion 2 and a tip portion
3, said tip portion including a pair of transversely spaced prongs,
4, 4 defining a U-shaped recess therebetween and from which
longitudinally extends a shank 5 which is received in bore 6 of
handle 2, said shank and bore including complementary mating flat
surfaces 7 which prevent the shank 5 from turning within said bore
6.
The handle 2 includes a recess 8 which exposes a portion of bore 6,
said recess being delimited at its forward end by a shoulder 9
against which abuts the forward end of a tongue 10 when the tip 3
is fully seated within said bore 6, this preventing the tip 3 from
pulling out of the handle unless the user presses down the tongue
10 until its forward end clears the shoulder 9.
The tip portion 3 can be made in one piece of molded plastic with
the tongue 10 being an integrally molded part thereof, said tongue
being flexibly bendable about its point of juncture with the
remainder of the tip body.
The end of each prong 4 includes a means such as coplanar, linearly
aligned slits 11 through which the length of floss F may be
extended, said slits being preferably tightly narrower than the
floss itself so that the floss is actually pinched or clamped
within said slits. If this were the case, even conventional smooth
floss could be firmly held in the slits of the holder of FIG. 1. In
any event, conventional smooth floss could simply be wound a few
turns around the ends of the prongs 4, analogously to the common
winding of floss around the user's fingers, and this would firmly
secure the floss to the prongs 4. In addition to such winding, the
floss could also be clamped within slits 11 and/or other slits 12
along the sides of prongs 4. In any event, the prongs are
resiliently flexed by the floss extending therebetween.
The special floss of FIG. 2, however, is of a length L between
successive nubs such that the floss will be tensioned between the
fork ends with the nubs 1 bearing against the outer sides of prongs
4. In this regard, it should be noted with regard to all
embodiments disclosed herein that the distance between the prongs
should be sufficient to bridge across a person's teeth while not
being so large as to inhibit use of the device within a person's
mouth, said distance being about 1 inch.
As is seen in FIG. 3 and the side views of the holders of the other
embodiments, the fork portion 3 is curved in one direction in order
to facilitate its insertion into the user's mouth.
The respective holders of FIGS. 5 and following each incorporates a
floss-tensioning feature.
The holder of FIGS. 5 and 7 is, for example, a one-piece integrally
molded body having a slot 14 opening at and extending centrally
from the base of the tip portion 28 along an axial extent of the
handle portion 20. The sides of the handle portion which define the
slot 14 include a plurality of axially spaced-apart recesses 21
adapted to receive the cylindrical pin portion 22 of a button
member which is selectively positionable at either of said recesses
21 so as to vary the transverse spacing S between the ends of the
fork prongs 24, said prongs being resiliently, flexibly yieldable.
The full and phantom lines in FIG. 5 illustrate the respective
positions of the prongs 24 corresponding to button member 25 in
different ones of recesses 21.
A loop floss O may be easily extended between the fork prongs 24
and around the hook members 26, which may be integrally formed on
one surface of the holder, while the button 25 is in the leftmost
recess 21, the floss loop O being slack at this time since the
prongs 24 are at their full-line position in FIG. 5. The button is
then slid to the next recess 21 thereby spreading the prongs 24 to
their phantom line position and tensioning the floss loop O. A
reversal of these steps facilitate removal of the used loop and
replacement thereof with a new one.
The hook members 26 will be properly positioned in conformity with
standard size loop floss. Quite clearly, however, the holder of
FIG. 5 as well as those of FIGS. 8, 10, 11, 13, etc., are not
restricted to the use of loop floss. Conventional elongate smooth
floss or the nubbed elongate floss of FIG. 2 could be mounted on
the holder along the same path shown in FIG. 5 for loop floss
excepting that the ends of this elongate floss would be wound a few
turns around the hook members 26 to secure the floss thereto, The
holder of FIG. 5, as also all subsequent holders to be described,
also includes slits 11 to accommodate a nubbed floss in the same
manner as illustrated in FIG. 1. Additionally, the respective
herein described embodiments may include side recesses 27 for
accommodating the turns of floss which may be wound around the fork
prong ends. The recesses 27 provide a seating for the turns of
floss so that said floss turns do not create a bulge along the
sides of the prongs which could irritate the user's mouth. In any
event, the recesses 27 serve as hooking means which prevent the
wound floss from slipping along the prongs in either direction. A
means of securing a length of elongate floss (whether nubbed or
not) is illustrated in FIG. 13 at F. The ends of the floss F simply
wind a few times at 69 around the ends of the fork prongs 68.
The holder of FIG. 8 is analogous to that of FIG. 5 in all respects
excepting for the fact that slot 34 includes only one recess 31 and
the button 35 has an oblong shank 32 instead of a cylindrical one
as in FIG. 5. The spreading of the prongs in FIG. 8, therefore, is
accomplished simply by turning button 35 90.degree. to the position
shown therefor in FIG. 8.
The holder of FIG. 10 also is analogous to that of FIGS. 5 and 8
excepting that the button members of the preceding embodiments are
replaced with a threaded means 45 extending transversely between
the arms 41 of handle portion 40 and arranged to adjust the spread
of said arms 41 which extend on either side of slot 44.
The holder according to the embodiment of FIGS. 11 and 12 comprises
a one-piece integrally molded body 50 which includes a handle
portion and a fork tip portion which can accommodate any type of
floss analogously to the previously described embodiments. The body
50, however, includes an axial through bore 51 which is threaded
along an extent thereof so as to threadedly receive the threaded
portion of a screw-type adjustment elongate member 52 which extend
through said bore and outwardly at opposite ends thereof to provide
a finger-grippable knob 53 at one end and a spherical head 55 at
the opposite end. Said head 55 fits into a correspondingly shaped
forms cup 56 located at the axis of two mutually inclined arms 57
which extend from said cup and up to the inner walls of the fork
prongs 58. The cup 56 and arms 57 are preferably integrally molded
together with the remainder of the body 50. It is quite clear from
FIG. 11 that normally the fork prongs 58 are spaced a certain
distance apart and that they can be further spread apart through
clockwise turning of member 52 which causes it to move axially
leftward (relative to FIG. 11) whereby its head 55 presses against
arms 57 tending to straighten them relative to each other. A length
of floss, therefore, is positioned across the prongs 58 while the
adjustment member 52 is in its screwed outwardly position, the
member 52 then being screwed inwardly of the body 50 in order to
spread prongs 58 apart and thereby tension the floss length. This
procedure is reversed in order to remove used floss from the
holder.
It is to be understood, of course, that the material of which the
body 50 is made is such as to permit resilient flexing of the
prongs 58 as well as of the arms 57.
The holder according to the embodiment of FIGS. 13-15 is analogous
to that of FIGS. 11 and 12 excepting that the adjustment member 62
is not threadedly engaged with the body 60 but is, instead,
threadedly engaged with the wedge element 67 which is wedgingly
slidable along the axial extent of a central slot 63 which extends
along in axial extent of body 60, said slot being a continuation of
bore 61 and opening at the juncture of the prongs 68.
The wedge element 67 is separate from adjustment member 62, each of
these members being insertable into body 60 through opposite ends
thereof, namely: member 62 being insertable through the free end of
the handle portion and wedge 67 being insertable from the fork end.
After being so inserted, these members are threadedly engaged with
each other through turning of member 62 whereby wedge 67 is pulled
into the hollow portion of the body 60, along the slot 63. This, of
course, results in a spreading apart of the prongs 68 and a
corresponding tensioning of the floss, as already described
relative to the embodiment of FIGS. 11 and 12.
The wedge 67 and the slot 63 will each be so shaped so as to
preclude rotation of wedge 67 within said slot. FIG. 15 illustrates
a six-sided elongate shape for this purpose.
The adjustment member 62 is insertable into the body 60 through the
open end of bore 61, said member 62 including a circumferential
groove defined between the shoulders 64 and 65. A radially inwardly
directed annular rim 66 integrally formed on the open end of body
60 fits into said groove to prevent axial movement or accidental
falling out of said adjustment member 62 relative to body 60. In
order, however, to permit passage of shoulder 65 past rim 66 (the
rim having a smaller diameter than said shoulder) during insertion
or removal of member 62, as for cleaning purposes, etc., the body
60 includes two diametrically opposed slots 66 extending from the
extreme end of body 60 so as to permit resilient flexing of the
body 60 (as shown in FIG. 14).
The holder of FIG. 16 is especially for use with loop floss O which
is passed through slits 11 and through the notch 72 in lever 71
which is pivotally mounted on the holder body 70 about an axis
transverse to the axis of symmetry extending between the prongs. It
is evident from FIG. 16 that with the lever 71 in raised position,
the loop of floss O may easily be mounted. A downward pivoting of
lever 71 effects a tensioning of the floss loop since the wall of
notch 72 is made to move away from the fork ends by such
pivoting.
The FIG. 17 embodiment comprises a one-piece integrally formed (as
by plastic molding) body 80 of resiliently flexible material, an
axially extending cavity 81 permitting flexing of the arms 85 of
the body located on opposite sides of the cavity. The end of the
cavity which adjoins the inner ends of the prongs 82 is, however,
closed by abutment shoulders 83 which abut each other along mating
serrated edges 84.
With reference to FIG. 18, the arms 85 are seen to be flexibly
transversely offsettable relative to each other to lie in different
planes whereby the inherent flexion therein causes the arms 85 to
come together in overlapping side-by-side relationship to the
position shown in FIG. 18. A length or loop of floss may now easily
be mounted on the holder since the prongs 82 are relatively close
together. The user then manually pushes the arms, against the bias
of the inherent flexion, in opposite directions so as to align the
edges 84 in a common phase (FIG. 19), this position being
maintained by the interlocking effect provided by edges 84. This,
of course, spreads the fork prongs apart and correspondingly
tensions the floss extending therebetween.
The FIG. 20 embodiment also is a resiliently flexible, one-piece
integrally molded construction comprising arms 95 normally
separated by an axially extending cavity 91. A person simply grips
the fork end of this holder and forces the prongs 92 towards each
other and applies the floss F across the end of the holder
whereupon the releasing of the prongs causes them to spring
outwardly to tension said floss F.
FIG. 20 illustrates the use of conventional smooth floss with the
respective different holders of this invention. The recesses 69
along the sides of the fork prongs provide a seating for the turns
of floss while avoiding that said turns form a bulge along the
outer side of the prongs, such bulges being possibly irritating to
the user's mouth.
The embodiment of FIG. 21 functions analogously to that of FIG. 20,
but in reverse. That is, the body 98 is originally formed, as by
plastic molding, whereby the arms 96 are normally relatively close
together and they are spread apart by forcing of the wedge member
93 into the cavity 94 between said arms 96. In other words, the
arms in the FIG. 20 embodiment are normally in their spread-apart
condition and must be flexed towards each other by the user in
order to mount the floss whereupon release of said arms causes them
to spread apart by themselves, while the arms in the FIG. 21
embodiment are normally in their close-together position and must
be flexed apart by force in order to tension the floss. Grooves 95
along the wedge 93 and corresponding ridges 99 along the sides of
the cavity 94 serve to lock the wedge within said cavity. Said
wedge 93 is itself integrally molded with the remainder of the body
98 and is, in this instance, resiliently flexibly joined thereto at
base 100. Alternatively, said wedge 93 could be a separately formed
member attached to body 98 by any known means.
Although not necessarily mentioned herein with regard to all
embodiments, it is quite clear that any of the types of floss
(conventional smooth and straight, nubbed straight, or looped) may
be used with either of said embodiments. Furthermore, all
embodiments which include a floss-tensioning feature are obviously
of resiliently flexible construction, especially relative to the
fork prongs.
The respective holders disclosed herein could be adapted to
incorporate a toothbrush as a part thereof simply by having said
toothbrush extending from the free end of the handle portions,
oppositely to the fork portion of the holder as shown in FIG. 21.
In other words, the herein disclosed floss fork and the toothbrush
101 would both share a common handle, namely, the portion of body
98 interconnecting the brush with the floss fork. This concept is
applicable to all the embodiments, even those such as shown in
FIGS. 11 to 13 in which case the brush would be integrally formed
with the rotatable adjustment members 52 or 62.
In fact, toothbrush handles are already commonly made of plastic
material and this same type of material could be employed to
produce the respective holders of this invention. As mentioned
previously, the holder material must be one which provides
resilient flexibility to the holder parts. In this regard, it
should be noted that while the drawing figures show the slits 11
and 12 as being rather open and large, these are, in fact, very
fine, razor-thin slits which tightly could grip a floss therein.
The resilient flexibility of the holder material, in fact, provides
an actual pinching effect on the floss when inserted into slits 11
or 12.
FIG. 23 illustrates an extremely simple to construct holder
according to this invention which, by virtue of its simplicity, is
so economical to produce that it particularly lends itself to being
marketed as a disposable item. This also applies to some of the
other holder embodiments disclosed herein which are also
economically produceable. The FIG. 23 embodiment comprises an
integrally molded, one-piece, fork-shaped body 103 which is simpler
than the holders of the preceding embodiments in that it does not
include in axially extending slot analogous to 81, 91, or 94.
Further, the body 103 does not necessarily include any hook
members, such as 26 (FIG. 5) for loop floss or any recesses such as
27 (FIG. 8), or any slits analogous to slits 11; instead, the floss
104 may itself be integrally molded with the body 103.
In other words, the complete assembly of FIG. 23 may be marketed
with the floss already preattached, so that the user is spared the
trouble of having to mount a piece of floss on the holder each time
that said user intends to use the floss. Instead, the user buys the
holders with the floss already properly mounted thereon. In this
regard, the floss 104 may be of the same material as that of the
body 103 and be molded simultaneously with the body in a single
operation. Alternatively, the floss 104 may be formed separately
from the body 103 and then fuse-bonded at 105 to the tips of the
body prongs 106. In either case, the respective materials obviously
must be of the moldable, fuse-bondable type. Further, in either
case, the floss is under the proper tension in the final
product.
The concept of fuse-bonding or integrally molding the floss to the
tips of the fork prongs as described relative to FIG. 23, could
also be applied to other herein disclosed embodiments of holders.
For example, a length of floss could be fuse-bonded or integrally
molded at the factory to the tips of the respective holders of
FIGS. 17 and 21 while the prongs of these holders are in their
close-together position. The floss would then be tensioned as
already described with reference to FIGS. 18, 19 and 22.
Analogously, the floss F in FIG. 20 could also be fuse-bonded to
prongs 92 while they are pinched towards each other, whereupon
releasing of same results in a tensioning of the floss.
Although the herein illustrated holders all have the floss
extending transversely to the longitudinal direction of the holder
handle, that is: the fork portion axis coincides with the handle
portion axis, the inventive concept is equally applicable to an
arrangement wherein the holder may be scythe-shaped, that is: the
axis U-shaped fork portion extending either perpendicularly or at
some other angle to the longitudinal axis of the handle
portion.
It is, further, to be understood that the floss which is useable
with any of the respective holders of this invention may comprise
conventional floss material, or any other material which is
suitable for the purpose. For example, the floss may be a synthetic
filamentary material, a cotton fiber, a metal wire, or of any other
material which can be produced in filamentary form.
It is, further, to be understood that various of the details
presented herein relative to the various embodiments are for
illustrative and not limitative purposes, it being within the
purview of one skilled in the art to vary such details without
departing from the disclosed inventive concept.
* * * * *