Note: Descriptions are shown in the official language in which they were submitted.
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BACKG~OUND OF THE INVENTION
Field of the Invention
This invention relates to a method of custom fitting
a pair of eyeglass frames to the wearer's nose, and to the nose-
piece formed in practice of such method. More particularly,
the invention relates to a custom fitting technique for eye-
glass frames in which an inexpensive wax wafer is heated andconformed to the wearer's nose and the frames to create a
contoured pattern which can be sent to and processed by an
eyeglass frames laboratory to form a permanent nosepiece which
is precisely adapted to the wearer's nose and is finally aligned
with the eyeglass frames while both the nosepiece and frames
are in worn position.
Description of the Prior Art
A particular problem with prior art methods of fab-
ricating an eyeglass frame is that it must be properly fitted
to the wearer's nose to both ensure correct alignment of the
eyeglass lens and to avoid discomfort caused by the necessarily
small contact area between the nose and nose pad thereby causing
discomfort to the wearer. Furthermore, the weight of the
frames, if not properly supported by the nose pads, tends to
cause the frames to slide down the wearer's nose, causing
chafing and irritation resulting in considerable distress to
the wearer.
Additionally, in normal use eyeglasses are repeatedly
removed from and returned to their position of use with the
frames placed against the nose and ears of the user. Unless
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the frames ar~ returned to the same position each time,the
lenses may well not be i~ proper position for optimal correction
of vision. Erratic positioning of the frames when returned
to use position will result in erratic correction with con-
sequent decrease of sharpness and clarity of vision,frustratingthe overall purpose and most important reason for wearing eye-
glasses, i.e. proper eye sight correction.
Present day opticians and the like maintain a large
inventory of eyeglass frames so that the wearer can select a
particular style of frames and lenses. Since the frames must
be properly fitted, the optician must normally carry a reasonably
large selection of both styles and sizes to accommodate his
customers. Additionally, it is desirable that opticians and
the like be able to accurately conform the bridge portion of
eyeglass frames to the wearer's facial features, and particularly
the nasal structure, as quickly as possible by relatively low
cost means, since the fit of the frames against the bridge of
the nose is most critical for the wearer's comfort as well
as proper vision correction.
Of particular interest with respect to fitted devices
for holding eyeglass frames on the wearer's nose is U.S. Patent
No. 3,701,592 to Fernandez. This patent discloses a pair of
spectacles provided with a nose bridge specifically contoured
to conform to the uppPr portion of the nose of the wearer. A
central portion of the bridge is made from a plastic or metal
material and includes a U-shaped cavity which forms a vacuum
around a portion of the nose for retaining the spectacles in
their proper position. An impression of the upper nose is
formed from a moldable compound applied to the inner surface
of a fixture. Den-tal stone, in its pliable state, is then
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molded with the impression form, and, after setting, forms a
replica of the nose. A two-part die i5 created incorporating
the shape of the nose replica, and an internal cavity is filled
with a settable plastic to form a vacuum holder piece. A
particular disadvantage of the vacuum spectacle bridge taught
by Fernandez is that it requires a rather large holder which
extends a significant distance along both the length and
width of the wearer's nose thereby detracting from the esthetic
appearance of the spectacles. Additionally, the nosepiece must
be initially deformed when the spectacles are positioned on the
wearer's nose in order to exhaust the air from the vacuum
retaining means so that the vacuum bond can be formed. Further-
more, in use, the application of suction to the nose over a
prolonged period has a tendency to turn the contacted area
of the nose red and to irritate the wearer's skin.
Also of interest is U.S. Patent No. 3,043,191 to
Lanski which discloses a method of fitting spectacle frames
to spectacle pads. The method disclosed by the Lanski patent
involves a positioning of a blank member having a pair of
interconnected pads on -the bridge of the wearer's nose. The
blank member is formed from a moldable material, softened by
heating in water, which is then formed to the shape of the
nasal structure. Adhesive is then used to attach the pads to
the frames of the eyeglasses.
Another method of fitting eyeglass frames with a
moldable material is disclosed in U.S. Patent No. 3,597,053,
to Massman. This patent describes spectacle frames having a
nose portion and a pair of temples, both of which have surfaces
for enhancing the engagement between the nose and temple and
ear portions of the head. The pliable material may be of the
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type which is either in a liquid state at ambient temperature
or is a heat responsive thermoplastic substance such that it
becomes malleable at temperatures slightly above ambient
temperature. In FIGS. 7 and 8, an inverted U--shaped bridge
segment is illustrated which is heated for softening of the
thermoplastic material. In this pliable state the nosepiece
is urged against the nose of the wearer causing it to conform
to the contacted surface of the nose.
Also of general interest are the following U.S.
patents:
Fensky 1,611,428
Montalov-~uenard 2,234,729
Nerney 2,308,200
Moeller 2,582,345
Baldanza 2,682,196
Hopmaster 3,189,913
Angelis 3,233,956
Gordon 3,345,737
Fordenberry 3,476,468
Olson 3,58~,939
SUMMA~Y OF THE INVENTION
According to one aspect of the invention, a pair of
eyeglass frames is custom fit to the nose of a wearer by a
procedure in part performed by an optician or the like and
in part performed by an eyeglass frame laboratory. The
optician or the like positions a wax wafer, heated as in warm
water until it is moldable, on the bridge of the wearer's
nose and applies pressure to conform its shape to that of
the nose. The wearer's eyeglass frames are then positioned
in their normal orientation on the nose and ears of the wearer
and an imprint of the frames is formed on the wax wafer.
Finally, the contoured wax form is removed from the wearer's
nose and cooled to fix its shape. The outline of the frames
in the area thereof contacted by the wax form is marked on
the wax form, as by a marking pen. The shaped negative replica
or pattern thus formed and marked is then processed by an
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eyeglass frames laboratory to form a plastic nosepiece there-
from. rrhe nosepieGe and eyeglass frames are then finally
fit on the wearer by the optician or the like, with quick
setting adhesive or the like being used to securely attach
the nosepiece to the frames in proper position.
According to another aspect of the invention, a method
of making and adapting the frames of eyeglasses is disclosed
in which the nosepiece can be easily and quickly fitted to
any type of spectacle frames without disturbing the original
alignment by adjustment of nose pads. As a related aspect
of the invention, a custom fit nosepiece is provided which has
a surface contact area much larger than the contact area of
conventional nosepieces, therehy spreading the weight of the
frames and reducing pressure point irritation so that wearer
comfort is significantly improved.
According to another aspect of the invention, a method
is provided for producing a nosepiece fabricated from a resin
or like material which can be either the same or different
than the material from which the frames are fabricated, with
the nosepiece a permanent and integral part of the frames
while in use.
Another aspect of the invention involves the custom
forming of a nosepiece for a pair of eyeglass frames by use of
readily available and low cost materials, such as petroleum
base wax,and molding plaster, such as dental stone, to initially
create an accurate replica of the wearer's nasal structure
and the adjacent portion of the frames, and then fabricate
a precisely shaped nosepiece ther~from under controlled
laboratory conditions.
These and other objects, features and advantages of
the invention will be apparent from the following detailed
description of various modes of practice thereof.
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BRIEF DESCRIPTION OE' THE DRAWING
__
FIG. 1 is a flow diagram illustrating a method of
custom fitting eyeglass frames according to the present
invention.
DETAI~ED DESCRIPTION OF THE P EFERRED METHOD
Referring to FIG. 1, the invention is generally con-
cerned with a method of custom fitting eyeglass frames in which
the portion of the procedure concerned with an initial impression
for the nosepiece and the final fitting of the spectacles frames
is p~rformed by an optician or the like, and the actual fab-
rication of the nosepiece is performed by an eyeglass frames
laboratory from a pattern sent to the laboratory by the optician.
Rather than maintaining a large stock of eyeglass
frames with a varied selection of sizes and nosepieces, the
optician need only maintain an inventory of eyeglass frames
which maximizes esthetic variations, but with a lesser variety
of sizes. In the same manner as with heretofore known methods
of fitting eyeglass frames, the patient first selects a pair
of eyeglass frames according to his own particular esthetic
taste. His eyesight is carefully measured on a lensometer,
or other such instrument, and a prescription derived for the
grinding of each corrective lens. This preparation of corrective
lenses for the eyeglass frames is well-known to those skilled
in the art, and it has no import with regard to the method of
the instant invention.
After the specific frames have been selected by the
patient, the opticiàn employs a wax wafer to make an impression
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of the bridge portion of -the nose of the wearer. In preferred
form, the wax wafer is shaped in a somewhat circular horseshoe
manner, and may be supplied to the optician from an appropriate
source such as a laboratory or frames supply house. Suitably
the wafers are provided in three separate si~es, e.g~ 1 1/4",
1 1~2" and 1 3/4" in diameter, and approximately 1/8" thick.
These three sizes have been Eound to be suitable for almost
all variation in patient nose structure. It should be under-
stood, however, that the wafer can be of different shapes and
dimensions, the precise size being dependent primarily on
both the nose structure and the desired thickness of the final
nosepiece, as will be more apparent from the following des-
cription. The material forming the wafer is suitably a thermo-
plastic substance, such as petroleum-base wax, and such that
it is relatively nonpliable or moldable at ambient temperatures,
but when heated to an elevated temperature, e.g. approximately
130, it softens and becomes moldable and formable in response
to applied finger pressure.
The processes for creating the neyative pattern begins
with the optician depositing one of the above described wafers
in water at a temperature of approximately 130F.
After the wafer has thus been rendered soft or pliable,
the optician positions it, while still warm, on the bridge
of the wearer's nose with the open end of the horseshoe shaped
wafer facing downwardly. The applier's fingers can then be
used to gently bend the water over the wearer's nose, and
to conform its convex surface to the configuration of the
bridge of the wearer's nose.
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With the wafer thus placed, the selected ey~glass
frames are positioned on the wearer in the proper viewing
position, with the bridge portion of the frames agains-t the
still warm wafer~ By applying pressure to the bridge portion
of the frames, the convex outer surface of the wax wafer is
imprinted with the contacting impression oE the frames.
Finally, the optician removes the frames and carefully
removes the resulting wax pattern from the nasal structure of
the ~earer. Without changing the shape of the replica, the
pattern is preferably quickly cooled as in cold water (at 80F.
or less) in order that its impressed shape will be fixed
without distortion. After the shape of the wax pattern has
thus been fixed, it is desirable to reposition it on the nose of
the wearer in order to ensure that its shape has not become
distorted, and to ensure the correctness of the imprint of
the frame of the glasses on the convex side of the pattern.
Also, at this time, the outline of the edge of the glasses
frame should be drawn on the convex side of the wax pattern
to assist in the shaping and cutting of the final pattern in
the laboratory, for proper esthetic appearance of the nosepiece.
The optician then sends the formed and marked wax
pattern to an eyeglass frames laboratorv for fabrication of
the custom fitted nosepiece. In the laboratory, a soft
mixture of finely divided self-setting molding composition,
such as the mix commonly known as dental stone, is poured
into the concave side of the wax pattern and allowed to set,
forming a first mold. With the wax pattern disposed on the
hardened dental stone mold, the outer edges of the wax pattern
are cut and shaped, resulting in a trimmed wax pattern which
is configured and dimensioned substantially to conform to the
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si~e and shape of the desired nosepiece. This procedure ensures
that no distortion of the wax pattern results during the cutting
and shaping the edges of the pattern along the outline marking
thereon. The first dental stone mold can also be used in the
finai steps by the laboratory personnel as a gage to check
the finished product.
During the next step performed by the laboratory
personnel, the trimmed wax pattern is used to prepare a second
dental stone mold, creating a two-piece die for use in the
forming of the custom fitted nosepiece. The face of one-half
of a split mold is first coated with a light layer of a
parting agent such as the material known as jelly ray. The
wax pattern is placed in position in the mold half, the mold
halves are reassembled, the mold cavity is filled with molding
composition, and the mixture is allowed to harden. The
hardened dental stone is then separated along the parting
agent layer, exposing the wax pattern. The wax pattern is
then removed and the cavity left in the dental stone constitutes
a precise negative of the wax pattern.
The solidified dental stone casting, which may other-
wise be termed a second, two-piece dental stone mold, is now
ready for the final forming operation. One suitable manner of
forming the final nosepiece replica involves use of a liquid,
thermosetting plastic or like material, such as CPI polyester
clear casting resin mixed with MEK-P hardener, both marketed
by Chemical Processors Inc. of St. Petersburg, Florida, which
is poured into an opening formed at one end of the second mold,
as by a conventional drill, filling the internal cavity of the
mold. However, it is to be understood that other settable liquid
resin materials could also be used in thus casting the nosepiece,
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such as acrylic polymers, polyvinyl chloride, or the like.
Anotller su1table method of forming the final nosepiece
involves use of a heat softenable resin body of sufficien-t
size to deform and fill -the internal cavi-ty o~ the two-piece
mold. For e~ample, a resin body in the form of a thin
(e.g. 1/8" thick) waEer, suitably about 1 1/2" in diameter,
can be used, the resin body and the two-piece mold being
heated to the softening temperature of the resin body, with
the resin body being inserted in the lower half of the dental
stone mold and the top half of the mold being put in place on
the lower half to form the body into the shape of the internal
cavity of the mold. The filled mold is then allowed to cool
to harden the formed resin body, which is then removed from
the mold, and ground and polished to form the final nosepiece.
In employing a softenable material as the substance from which
the final nosepiece is formed, and as will be understood, any
type of resin or like material can be used which is essentially
thermoplastic in nature and has a softening temperature above
temperatures normally encountered during use of the nosepiece,
i.e. a softening temperature of at least about ]60F. Vinyl type
resins are quite suitable for the purpose, and typically involve
heating of the mold and resin to a temperature of about 200F. to
mold the nosepiece. Acrylic type resins are also suitable, and
typically involve heating of the mold and resin to about 350F.
during forming of the nosepiece. Other resins having the desired
heat softening characteristic and utilizable for the purpose will
readily occur to those in the art to which the invention is addressed.
After allowing sufficient time for the formed resin
or the like to solidify, the two-piece mold is separated and
the formed replica is removed. Any rough edges or surfaces
; on the formed plastic body are then ground and polished,
forming the final nosepiece which includes respective concave
and convex configurations which are the exact shape of the
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bridge of the wearer's nose and the bridge portion of the
eyeglass frames.
As shown in FIG. 1, the nosepiece is returned to the
optician or the like for final alignment on the nose of the
wearer and attachment to the frames of the glasses. With the
nosepiece on the bridge of the wearer's nose, the eyeglass
frames are again positioned in their proper corrective position
on the wearer's head. The bridge of the eyeglass frames con-
tacts the convex surface of the nosepiece while the concave
surface of the nosepiece is disposed on the wearer's nose in
the supporting position. While maintaining this alignment
a thin film of quick-setting adhesive, such as the cyanoacry-
late ester, marketed under the trademark SUPER GLUE-3 by
Woodhill Chemical Sales Corporation of Cleveland, Ohio, or
the like, is placed on the contact surfaces of the eyeglass
frames and the custom fitted nosepiece. Hardening of the
adhesive permanently attaches the nosepiece to the frames of
the spectacle in proper position to provide maximum comfort
to the wearer while maintainin the proper corrective orientation
of the eyeglass lenses.
As will be apparent from the foregoing description, a
significant aspect of the disclosed method of custom fitting
eyeglass frames is that some of the steps are performed by
the optician or the like, and other steps are performed in
an eyeglass frames laboratory. The initial steps, quickly
accomplished with the patient in the practitioner's office,
do not require expensive, complicated equipment, but only a
readily manufacturable inexpensive wax wafer. The intermediate
steps of the method, generally requiring more time and exactness,
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are performed in an eyeglass frames labora-tory whlch has the
necessary raw materials and equipment to efficiently fabricate
and finish the thermoset nosepiece from the wax pattern sent
to it by the practitioner. The final steps of alignment and
attachment of the nosepiece to the eyeglass frames, essential
to ma~imize comfort, are performed by the practitioner with
the spectacles on the patient.
From the foregoing, various additional modifications,
revisions and adaptations of the method and formed article
hereabove described will occur to those skilled in the art
to which the invention is addressed, within the scope of the
following claims.
