Note: Descriptions are shown in the official language in which they were submitted.
~ 15773~
~URLER BRUSH LOCKrNG NECH~NI5M
I. Description:
Background of the ~n~ention
This invention relates to lockable, rotatable
heated curling brushes which are used for styling and
curling hair. More particularly, this invention relates
to brake pad and drum structures used as the locking
mechanism in lockable, rotatable heated curling brushes.
Rotatable heated curling brushes ccmprise generally
a rod housing which serves as a handle, an inner tube
fixedly connected at its rear portion to the front part
of said handle and protruding therefrom, a heater inside
said inner tube electrically connected to a swivel cord,
and an outer tube rotatably supported by said inner
tube, said outer tube having a round brush on the outer
surface thereof, either with integral brush projections
or removable projections. The inner tube is fixed to
the handle by a bolt or pin arrangement and the outer
tube is held in the handle by a circular guide in the
front end of the handle which mates with a flange at
the rear of the outer tube. ~his flange, in conjunction
with a tension loaded button device forms a braking
mechanism which hol~s the round brush fast or releases
it to freely rotate. In accordance with this invention,
the flange acts as the brake drum and the button, with
a brake pad therein, acts as the brake shoe.
q~
1 15773~
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The outer tube is supported by the inne~ tube and
held captiYe by an in~ard fac~ng groove on the ~ron~
edge of the handle which mates with the flange. The
front end of the ou~er tube can be supported b~ the front
end of the inner tube. The tnner tube is in heat
conducting relationship with the heater and the outer
tube. The inner tube can-be made of a heat conducting
material which conducts sufficient heat from the heater
to the outer tube to enable hair curling temperatures to
be reached. Certain plastics and aluminum or other heat
conducting materials are suitable. The outer tube is
made of plastic when the projections are integral, and
of aluminum when the pro~ections are removable. The
projections are preferably made of plastic. The heater
' 15 is ordinarily a positi~e temperature coefficient tPTC)
thermistor.
Rnown curlers with lockable rotatable heated
brushes have locking mechanisms in which the flange
at the rear of the outer tube has spaced notches which
` 20 in conjunction with a spring latch de~ice attached
~; either to the handle, to the inner tube, or both,
holds the round brush fast or releases it to freely
rotate. These locking mechanisms operate generally
c satisfactorily but locking can only be accomplished
at the notches, not between them. There is a need,
therefore, for a loc~ing mechanism wherein locking
will occur at all locations on the flange.
SUMMARY 0~ T~E INVEN~ION
Accordingly, it is an ob~ect of this invention
to pxo~ide an improved loc~ing mechanism, suitable
for use in hea~ed, lockable, rotatable curler brushes
which will enable the user to hold the brush against
ro~ation in all positions and without the need to rotate
the brush until a detent is reached.
1 15773`~
The locking mechanism of th~s in~ention comprises
spring loaded button a~tached to either the handle, ~he
inner tube, or both, of a rotatable heated curiing brush
which has a brake pad placed on the front face thereof
in a position ~hich wtll enable the ~rake pad to come
into braking contact with the rear face of the outer
tube. The rear face of the outer tube is preferably
radially serrated on its surface to increase the friction
~etween it and the brake pad, thus enhancing the braking
or locking effect. A suitable configuration for use in
this inYention i9 an outer tube which is flanged on its
rear end. ~he invention will be described with such a
flanged outer tube.
The button is nested on an opening in the front
portion of the handle, and a spring between the button
and the inner tube or a projection on the inside of the
handle preloads it so the brake pad presses on the outer
tube which is the~eby held in a locked position. By
pushing the button against the spring, thereby moving the
front portion containing the brake pad away from the
flange, one causes the release of the outer tube so it
can freely rotate. The distance the button must be
depressed to release the outer tube is significantly
less than needed for locking mechanisms with notches
and a spring latch since the distance need only be
sufficient to relieve the pressure of the brake pad,
e.g. 1 mm or less.
I 157734
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The ~rake pad is made o a m~terial which is stable
under the temperatures at wh~ch the brush is heated and
is wear resistant. In addition, the material should Pe
of a surface hardness and coefficient of friction wh~ch
permits it to ade~uately frictionally engage the flange
surface and prevent rotation. A polyurethane elastomer
having a Shore A Durometer hardness of 85 1 5 is suitable,
a typical material is MP 1880 Urethane sold by Stevens
Flastomeric and Plastic Products Inc., East~ampton,
Mass. If the elastomer has too low a hardness, it tends
to wear out, particularly when abused. If the elastomer
has too high a hardness, it does not have sufficient
frictional properties to lock the roller brush.
The pad is bonded to the button with a suitable
contact bonding agent -uch as Pliobond*2030, sold by
Goodyear Chemical Division of Goodyear ~ire and Rubber
Company, Ashland, Ohio.
The button can be of a ~ariety of shapes and con-
figurations, depending on the particular curling brush
and the desired design configuration. The button can be
circular or it can be elongated. A preferred design is
an elongated button which qenerally conforms to the
surface of the handle, including the portion which holds
the flange of the outer tube. The button can be attached
pivotally to the inside of the handle by means of projections
or it can be pi~otally attached to projections on the
top of the inner tube, or both. In any case, a compression
coil spring under the rear of the ~utton, between the
button and the inner tube, keeps the brake pad on the
~utton frictionally engaged to the flange face of the
outer tube.
*Trademark
~ 1 157734
--5--
The button also can be attached to a pie~e af
spring metal leaf which is o~ the inner face of ~he
handle. The spring metal leaf will preload the ~utton
so the brake pad is held against the flange face of the
outer tube. Another suitable structure is a spring
loaded sliding button. T~e spring loaded sliding ~utton
can be ~n a guide track on the handle ~ith the spring
which is parallel to the longttudinal axis of the handle
and between the rear o f the ~utton and a boss on the
inner surface of the handle, preloading the front of the
button to ~hich the brake pad is bonded, against the
face of the fiange, keeping it locked. Release, allowing
the outer tube to rotate, is obtained when the button is
pushed and held toward the rear of the handle.
! 15 The loc~ing mechanism of this invention can be
incorporated into a variety of heated rotatable curling
brushes, preferably those having a flanged rotatable
member. One suitable type is wherein the inner tube and
outer tube are made from the same plastic and the pro-
2~ jections of the brush on the outer tube are integral
therewith. Another curling brush which is suitable is
one wherein an inner tube of aluminum replaces the
plastic inner tu~e and is structured so that the heat
generated is substantially evenly distributed throughout
the brush. Rotating curling brushes with removable
projections and those with steam generating devices are
also suitable for use with the locking mechanism of this
~nyention.
Brief ~escrtptton of the Drawings
3a Figure 1 is an exploded perspective view of a locking
mech~nism of this inYention;
~ 157734
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Figure 2 is a s$de sectiQnal vie~ o~ the locking
mechanism shown in Fi~ure l;
Figure 3 is an end secttonal ~iew o~ the spring
loaded button showing its attachment to the inner tube;
Figure 4 $s a perspective exploded view of the
braking mechanism of this tnvention wherein the button
is slidable;
Figure 5 is a side sectional view of the locking
mechanism s~own in Figure 4:
~i~ure 6 is a side sectional view of a heated
rotatable curling ~rush ha~ing plastic inner and outer
tubes with the loc~ing mechanism of this invention;
~ igure 7 is a side sectional view of a heated
rotatable curling brush ha~ing an aluminum inner tube
1~ with the locking mschanism of this in~ention therein;
Figure 8 is a side sectional view of a heated
rotatable curling brush having remo~able projections,
with the locking mechanism of this in~ention therein;
Figure 9 is a side sectional view of a heated
2Q rQtatable curling brush ha~ing a steam generator an~
remo~a~le pro~ections with the braking mechanism of this
inven~ion;
Fi~ure 10 is a perspecti~e exploded end view of the
curling bxush outer tube of Figure 8 with removable
2~ projections.
I 157734
-1-
Figure 11 is a pqrspectiYe Yiew of spike PXoiec~ions
~ with rounded e~ds;
f Figure 12 is a perspecti~e Yiew of triangular shaped
proiections.
Detailed Description of th-e In~ention
Referring to the drawtngs, the locking mechaniæm shown
in Figs. 1, 2 and 3, is the preferred embodiment of the
locking mechanism of this invention, i.e., wherein the
buttQn 1 ~s pivotable on the pro~ections 9 which fit into
sockets 10 in the inner portion of the handle 3. Sockets
10 are formed by the upper and lower portions of the
handle 13 when they are mated b~ the tongue and groove 17
and held together with screws 18. The button 1 is generally
rectangular with rounded corners 12 on the back end and a
raised portion 2, the outside of which conforms to the
shape of the raised portion 19 on the front of the handle
13. The raised portion 2 contains a notch 3 on its underside
along its width which fits over the flange 4 of the ou~er
tube 5 and holds it in rotating relationship. The notch 3
matches the track 14 around the inside of the front of the
raised portion 19 of the handle 13 for holding the flange
4 of the outer tube 5 of a cylindrical curling brush in
rotary relationship.
The thumb butto~ 1 can be made of any moldable material
that is stable under the conditions of use; plastic is
preferred.
The face 6 of the flange 4 can be smooth. The preferred
structure ~s serrated with radial groo~es 7 as shown in
I 157734
Fig. 1 because ~reater friction is created between them
and the brake pad 8. In a preferred embodiment, the
serrations 7 are around the complete circumference of the
face of the flange 4. Any suitable number of serrations 7
can be made, however, they must not be further apart than
the width of the brake pad 8 or loc~ing will not occur
without the need to rotate the brush until serrations 7
are in contact with the brake pad 8. The use of 144
radial serration 7 is suitable, although lesser or more
can be put on the face of the flange 4. The flange 4 can
be composed of a variety of materials including plastics
such as polycarbonate, a relatively poor heat conductor.
The flange 4 and the outer tube 5 can be integral when the
outer tube S is plastic. This is not the preferred embodiment.
Preferred is an aluminum outer tube 5 attached to the
flange 4 by a sleeve fitting. They can be fabricated in a
conventional manner such as injection molding.
The brake pad 8 bonded to the rear face of the notch
3 in the front portion of the button 1 is made of an
elastomer, preferably polyurethane. It is preferably in
the middle third of the width of the button 1. The brake
pad 8 i8 placed so it will contact the face of the flange
4 and clamp it by friction, preventing rotation.
At the rear of the thumb button 1 on the underside is
a recess 15 for accommodating the top of a compression
spring 16. The spring 16 can be made of any conventional
material, however, 0.024" diameter music wire is preferred.
The spring 16 should ha~e sufficient strength to hold the
rear of the thumb button 1 so that the brake pad 8 is pre-
loaded against the flange face 6 and if serrations 7 arepresent, against them so the outer tube S is held against
rotation.
~ 157734
g_
Also, the ~ottom of the thumb ~utton 1, contains a
st~ucture having a pair of knobs ~, one on e~ch side.
These knobs ~ act as axles when the button 1 is pivotally
attached to sockets 10 in the inner portion of the handle
13. It is also possible to have sockets instead of knobs
and pi~otally attach the button 1 to knobs on the inner
tube 11. Pressing the button 1 down at the back raises
the brake pad 8 away from the flange 4, allowing it to
rotate freely.
The sliding thumb button 114 depicted in Figs. 4 and
S has guides llS which fit into a guide track in the
forward end of the handle 113. The bottom of the thumb
button 114 has a boss 121 which recei~es the front end of
a spring 116 that is longitudinally placed on the outer
surface of the inner tube 111. The inner tube 111 has a
boss 112 which receives the rear end of the spring 116.
The front face of the thumb button 114 has a brake pad 118
bonded to it. The spring 116 has sufficient tension to
preload the thumb button 113 forward against the face 117
of the flange 119 and thereby hold the outer tube 120
against rotation. The face 117 of the flange 119 can be
smooth or have serrations 122 as shown in Fig. 4. Rotation
is made possible by sliding the thumb button 114 to the
rear against the tension of the spring 116. When the
button 114 is released, the spr~ng 116 forces it forward
to cause the bra~e pad 118 to hold the outer tube 120
against rotation.
Re~erring to Figures 6 and 7 where like numbers
indi~cate like parts, the heated hair curler as shown
comprises a rod housing 61 which serves as a handle, and
a~ inner tuhe. ~n Figure 6 the inner tube 62 is made of
~ 157734
--10--
the same plastic a~ the .outer tube 63. In Figu~e 7 the
inner tube 72 is made of aluminum prot.~.uding from the ~od
housing 61. The aluminu~ ~nner tube 72 is ~anufactured
either by deep drawing, extrusion or other means. .The
inner tubes 62 and 72 are attached fixedly to the rod
housings 61 by means of ~ post 82 attached by a screw 83
to the inner surface o the housing 61 through a hole in
.~ the inner tubes 62 and 72.
,:
The inner tubes 62 and 72 serYe to rotatably support
the plastic outer tube-63 and to conduct heat from the
heater 66 to the outer tube 63. The coupling 65, between
the handle 61 and the outer tube 63, holds the round brush
64 supported by the outer tube 63 by a circular guide 67
in the front of the handle 61 which mates with the serrated
flange 68 at the rear of the outer tube 63. The electric
heating device 66 is a positi~e temperature coefficient
(PTC) thexmistor located inside the inner tubes 62 and 72
and is connected to a power source, not shown, by electric
wires 70 which are introduced into the handle (rod housing)
61 and connected at commutating device 69 from the PTC
thermistor 66 into the handle 61 to a swivel coupling
78.
The inner tubes 62 and 72 have a blind front end 77
which pr.ovides an axial forward stop for the heater 66.
This blLnd front end 77 on the inner tubes 62 and 72 abuts
the blind front end 74 of the outer tube 63. The outer
diametexs of the inner tubes 62 and 72 are close fitting
within the inner diameter of the outer tube 63 to maintain
maximum hea~ transfer. The outer tube 63 has an unheated
grip 7~ on i~s front end. The rearward end of the outer
t~be 63 has a flange 68. The flange face can be smooth,
1 157734
however, in the prefersed depicted embodiments in ~igs.
6 and 7, the flange face is serrated as shawn ~ Pig. 1
onto which a ~rake pad 76 on the front of a thumb button
79 can press keeping the outer tube 63 from rotating.
The thumb button 79 is pivotally supported on either of
the inner tubes 62, 72 at a pi~ot axis 80. The button
79 is supported on either of the inner tubes 62, 72 with
a compression spring 85 which flts into a notch 86 on
the button. In this way the brake pad 76 is automatically
preloaded against the serrated face of the flange 68 to
hold the outer tube 63 against rotation until the operator
actuates the button 79 by pressing to disengage the
brake pad 76 allowing the outer tube 63 and brush 64 to
freely rotate.
The above discussion is directed to the em~odi-
ment of this invention in which the heated curling
brush has a plastic outer tube and a plastic or
aluminum inner tube. It is also possible to utilize
the locking mechanism of this invention in a heated
curling brush haYing remo~able projections as shown
in F~gures 8, 9 and 1~.
Referring to Figures 8, 9 and 10, where li~e numbers
indicate like parts, the heated hair curlers shown comprise
a rod housing 61 ,which ser~es as a handle, and an aluminum
inner tube 72 protruding from the rod housing 61. The
inner tube 72 is fixedly attached to the rod housing 61 by
means of a post ~2 attached by a screw 83 to the inner
surface of the housin~ 61 through a hole in the inner tube
72.
The innex tube 72 serves to rotatably support the
ou~er tube 163 and to conduct heat from the heater 66 to
- the outer tu~e 163. The coupling 65, between the handle
1 1S7734
-12-
61 and the outer tube 163 holdQ t~e serrated ~lange 68
of the outer tube 163 in a c~rcular guide 67 in t~e
front of the handle 61 which mates ~ith the serrated
flange 68 at the rear of the outer tube 163. ~he flange
68 is made of a plastic which is a poor heat conductor.
It is fitted onto the outer tube 163 by a slee~e fitting.
The electrlc heating device 66 is a positive temperature
coefficient (PTC) thermtstor located inside the inner
tube 72 and is connected to a power source, not shown,
by electric wires 7~ which are introduced into the
handle (rod housing) 61 and connected to a swivel
coupling 78 at a commutating device 69 by the wires 70
extending from the PTC thermistor 66 into the handle 61.
The outer tube 163 is made of aluminum from the
front end to the flange 68. The outer tube has grooves
93 running longitudinally ~rom the front end to the
flange 68. The grooves 93 as shown in Figure 10 are
dovetail shape, however, any convenient shape is satis-
fa~tory. The grooves 93 recei~e in sliding relationship
rows of projection~ 9S shown in ~igures 10, 11 and 12 on
guides 96 which mate with the groo~es 93 to form the
curler brush. There are ei~ht grooves 93 and eight rows
of projections 95 on the outer tube 163. It is possible
to use fewer rows of projections 95, however, eight has
been found to be most ~uitable. The projections 95 and
guides 96 are p~eferably made of a rubbery plastic which
conducts the heat from the aluminum outer tube 163 ~ut
not so efficiently that the user is burned. A thermoplastic
polyeste~ eiastomer such as Dupont Hytrel*~555-HS sold
hy, E.I. Dupont, W~lmington, Delaware is a suitable
material. The flexible projections 95 can be of any
suitable shape which when utilized will not tangle the
*Trademark
~ 157734
-13-
hair. It has been found th~t w~ile relatively rigidprojections are operable, flexible pro~ections are
preferred since they have less tendency to tangle the
hair. Preferred are cylindrical or slightly tapered
proiections with rounded tips perpendicular to the guide
96, as shown in Fig. 11. Another configuration can be
triangular with a flat front and a flat back both of which
are perpendicular to the guide 96 as shown in Fig. 12.
As shown in Figure 8, the inner front end of the
outer tube 163 has threads 98 for receiving an end 99
which screws into the threads 98. This end 99 prevents
the rows of pro~ections from sliding out. It is made of a
low heat conductive plastic such as polycarbonate and
does not become heated. If the projections 95 are to be
changed, the end piece 99 is unscrewed and the projections
95 are removed. The inner tube 72 has a blind front end
100 which is in direct contact with the forward end of the
heating device 66. The end 100 of the inner tube 72 is
not in contact with the removable end piece 99. This
makes sure the end piece 99 is cool to the touch so it can
be removed without danger to the user. The end 100 of the
inner tube 72 provides an axial forward stop for the
heating device 66. The outer diameter of the inner tube
72 is close fitting within the inner diameter of the outer
tube 163 to maintain maximum heat transfer. These diameters
may be very close fitting and still permit free rotation
of the outer tube 163 in view of the compatible coefficients
of thermal expa~sion Oc the aluminum outer tube 163 and
aluminum inner tube 72.
~ 157734
-14-
The rearwaxd end of the outer tube 163 is made of
plastic and is a flange 68 as shown in Figs. 8 and 9
~ith serrations on its face, as illustrated in Fig. 1,
against ~hich a ~rake pad on the front end of the push
button 1~6 can be engaged. The push button 106 is
pivotably supported on the inside of the handle 61 at
pivot axis 107. The button 106 is supported against
the inner tube 72 with a compression spring placed
between a notch on the underside of the rear of the
button 106 and a projection from the post 82 which
holds the inner tube 72 in the handle 61. In this
way, the brake pad is automatically swung into position
to hold the outer tube 163 until the operator actuates
the button 106 for disengagement, then the outer tube
163 and round brush rotate freely.
In the case of a steam curling brush as depicted
in Fig. 9 the outer tube 163 has a series of perforations
94 in the base of the grooves 93 for the projections
95, in order to allow steam generated therein to
escape. It is preferred to have perforations in
alternate grooves otherwise essentially all the steam
will escape at the front perforations and very little,
if any, at the rear perforations with the result that
uneven curling is obtained. In addition, the end 101
which screws on and off the outer tube 163 is a guide
for the water reservoir 99 and the sliding collar 103.
Also when the end 101 is removed by unscrewing threads
98, the projections 95 can be remo~ed. The water
reservoir 99 s~rews into the sliding collar 103. This
collar 103 contains a wick 102 which is in contact with
the end of the inner tube 100 when the end 99 is depressed
axially. The water reservoir 99 can be removed for filling
by unscrewing, however, it is possi~le to have an end which
snaps in rather than screws in. The full reservoir 99 is
I 15773~
-15-
then reinstated into the collar 103. The colla~ 103 is
displaced axially inward by pushing on the end 99 causing
the wet wick to be moved into contact with the end 100 of
the inner tube 72. The water in the wick becomes heated to
steam from the heat of the inner tube 72. The steam escapes
through the perforations 94 in the outer tube 163 and in the
projection guides 96. The perforations in the guides 96 are
not positioned directly over the perforations 94 in the
outer tube 163 in order for the steam to be more uniformly
distributed along the length of the outer tube 163. The
water reservoir g9 and collar 103 are held in an extended
position by a compression spring 104 which is longitudinally
placed between a boss 105 on the outer shoulder of the water
reservoir 99 and a notch 109 in the end 10}. The outer tube
163 is centered on the inner tube 72 by sets of dimples 108
on the inside of the outer tube 163 at each of the alternate
grooves 93 which do not contain perforations 94. This
assures uniform distribution of steam around the circumfe-
rence of the outer barrel 163.
The heated loc~able rotatable curling brush, in
use, operates as follows. The electric plug, not shown, is
plugged into an electric power source which heats the PTC
heating device causing the inner tube to become heated and
by condu¢tion to heat the outer tube, the brush projections
2S thereon do not become heated but may become slightly warm,
however, their function is to provide a grip for winding
the hair. When the curler brush is heated, the operator
winds the hair around the curler brush ~ith the brake
engaged. When the hair is curled as aesired, the button
is pushed and held, releasing the outer tube and the brush
to rotate freely. ~he curler brush is then pulled outward
from the head, releasing the hair.
If steam is desired, the steam curling brush depicted
! in Figure g can be used. After the hair is rolled up, the
~ 157734
-16-
end cap of the outer tube containing the water reservoir ispushed, generating steam whic~ escapes through the
perforations in the outer tube and projection guide. The
device is removed from the hair as described above.
Other known rotata~le curling hrushes can also be
adapted to utilize the loc~ing mechanism of this
invention, which invention is no~ intended to be limited to
a specific curler brush.
