Note: Descriptions are shown in the official language in which they were submitted.
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BACKGROIl~D OF THE INVENT ION
The present invention relates to improvements
in hair dryers. More particularly, the invention i5
concerned with an improved hand held hot air hair dryer
which does not require electrical connection to an AC
external source for operation.
A conventional hand held hot air hair dryer
usually comprises a nozzle for exhausting air, a heating
chamber disposed proximate the nozzle and containing
electrical heater coils, and a motor-driven fan for
passing air through the heating chamber to thereby heat
the air prior to exhausting through the nozzle. Two
independent electrical switches are generally used, one
for varying the power supplied to the heater coils so as
to vary the temperature of the heated air and the other
for varying the speed of the motor so as to vary the
velocity of the air flow exiting the nozzle. Such a
hair dryer must necessarily be connected to an AC
external source by means of an electrical wire for
powering both the motor and heater, the power requirement
of the latter being in the range of about 600 to about
1200 watts. The hair dryer is therefore limited in use
since it can only be operated where there is an AC
external source available for providing the necessary
electrical power. Moreover, the electrical wire which
serves to connect the hair dryer to the A~ external
source is annoying and usually hinders the movement of
the operator's hand holding the hair dryer.
SU~qMARY OF THE INVENT ION
It is therefore an object of the present
invention to overcome the above drawbacks and to provide
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a cordless hand held hot air hair dryer.
In accordance with one aspect of the invention,
there is provided a cordless hand held hot air hair dryer
comprising nozzle rneans for exhausting air, a heating
chamber disposed proximate the nozzle means, fuel supply
means for storing a vaporizable fuel in a liquid state,
and catalytic heating means in fluid flow communication
with the fuel supply means and including a catalyst
member disposed within the heating chamber for combusting
vaporized fuel suppli.ed from the fuel supply means. The
hair dryer of the invention further includes battery~
powered motor means and fan means driven by the motor
means for passing air through the heating chamber so as
to contact the catalyst member, to thereby heat the air
prior to exhausting through the nozzle means. Manually
operated control means are also provided for controllin~
the amount of current applied to the motor means and
proportionally adjusting the flow of fuel to the heating
means to thereby regulate the temperature o~ the heated
air in relation to the amount of air flow exhausted
through the nozzle means.
According to a preferred embodiment of the
invention, the motor means is powered by rechargeable
battery means connected thereto. Preferably, the hair
dryer ~urther includes AC-DC converter/transformer means
coupled to the battery means for recharging same.
By the expression "cordless hand held hot air
hair dryer" as herein employed is meant a hand held hot
air hair dryer which does not require electrical connec-
tion to an AC external source for operation, apart from
that required for recharging the battery means where re-
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chargeable battery means are used.
In a pre~erred construction, the hair dryer
comprises a housing having a central portion in which
the motor means and fan means are mounted, a tubular por-
tion extending forwardly of the central portion and
defining the heating chamber with the nozzle means being
provided at a free end of the tubular portion, and a
handle portion depending from the central portion in
which the control means, battery means and AC-DC con-
verter/transformer means are mounted. The fuel supply
means comprises a pressure vessel arranged rearwardly
of the central portion and defining a reservoir for
containing the fuel, the pressure vessel having a bottom
wall provided with a refill valve for refilling the
reservoir with fuel. This arrangement is particularly
advantageous since it enables the hair dryer to be
recharg~d with electricity and refilled with fuel by
means of a combined electric and fuel recharging unit
which the present invention further provides.
Thus, the present invention also provides,
in a further aspect thereof, a combined electric and
fuel recharging unit for use in recharging a hair dryer
as described just above with electricity and refilling
same with fuel, comprising means for supporting and
retaining the dryer in an upright position while allowing
free vertical displacement thereof, means for holding a
fuel container having at an upper end thereof a f~el
discharge valve in an upright position with the fuel
discharge valve positioned in alignment with the refill
valve of the dryer, electrical female plug meàns enga-
geable with electrical male plug means housed in the
handle portion of the dryer and connected to the AC-DC
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converter/tran 9 former means for supplying same with
electricity, the electrical female plug means being
mounted for limited vertical displacement thereof
between upper and lower positions, and spring means
S upwardly biasing the electrical female plug means to the
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upper position. The hair dryer lS conveniently re-
charged with electricity and refilled with fuel by
downwardly displacing the dryer to a recharge and
refill position causing electrical connection between
the electrical male and female plug means and engage-
ment of the refill valve with the fuel discharge
valve and by maintaining the dryer at the recharge
and refill position against the upward force exerted
by the spring means for a period of time sufficient to
allow the reservoir of the dryer to be refilled with
fuel. Upon release of the dryer, -the electrical female
plug means is upwardly moved by the spring means from
the lower position to the upper position to upwardly
displace the dryer and thereby cause disengagement of
the refill valve and the fuel discharge valve from one
another while maintaining the electrical connection be-
tween the electrical male and female plug means. In
this manner, the battery means is maintained charged
while accidental leakage between the refill valve and
fuel discharge valve, which otherwise could occur if
the valves remained engaged, is prevented.
According to a particularly preferred embodiment
of the hair dryer of the invention, the control means are
actuated by a single manually operable actuator member.
To this end, a conduit means interconnects the fuel
supply means with the heating means and the control means
include valve means in the conduit means for varying the
flow of fuel to the heating means and variable resistor
means connected intermediate the battery means and the
motor means for varying the amount of current applied to
the motor means, the actuator member being operatively
connected to both the valve means and variable resistor
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means for actuating same. Preferably, the actuator
member is continuously movable along a rectilinear path
between first and second limit positions whereby to
increase the amount of current applied to the motor
means when the actuator member is moved in a direction
toward the second limit position or to decrease the
amount of current when the actuator member is moved in a
direction toward the first limit position while corres-
pondingly increasing or decreasing the flow of fuel to
the heating means to thereby provide heated air having a
substantlally constant temperature independently of the
amount of air flow exhausted through the nozzle means.
The variab:le resistor means preferably comprises
a rheostat having an elongated resistor element and an
electrically conductive sweeping arm in frictional
sliding engagement with the resistor element for sweeping
same, the arm being fixedly connected to a rotatably
mounted shaft for permitting the arm to sweep the resistor
element when the shaft is rotated. The actuator member
is connected to the shaft by connecting mea~s adapted to
convert the translational movement of the actuator member
into a rotational movement for rotating the shaft.
The valve means, on the other hand, preferably
comprises a valve body having a fuel passageway formed
therein and a valve stem movable in the valve body to
adjustably restrict the fuel passageway. A cam disk is
fixedly mounted to the shaft and frictionally engages the
stem for moving same when the shaft is rotated in response
to a displacement of the actuator member.
B~IEF DESCRIPTION OF THE DRAWINGS
. ~
Further features and advantages of the invention
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will become more readily apparent from the following
description of preferred embodiments thereof as illustrated
by way of examples in the accompanying drawings, in which:
Figure 1 is a part-sectional view of a cordless
hand held hot air hair dryer according to the invention,
seen installed on a combined electric and fuel recharging
unit for recharging the dryer with electricity and
refilling same with fuel,
Figure 2 is a sectional view taken along line
2-2 of Fig. l;
Figure 3 is a fragmentary part-sectional view
illustrating the control means of the hair dryer shown
in Fig. 1,
Figure 4 is a sectional view taken along line
~-~ of Fig. 3,
Figure 5 is a sectional view taken along line
5-5 of Fiy. 3,
Figure 6 is a fragmentary part-sectional view
illustrating the valve component of the control means
shown in FigO 3,
Figure 7 is a schematic diagram illustrating
the circuit used for varying the amount of current applied
to the motor drlving the fan of the hair dryer shown in
Fig. 1,
Figure 8 is a fragmentary part-sectional view
taken along llne 8-8 of Fig. 1, and
Figure 9 is a fragmentary sectional view taken
along line 9-9 of Fig. 1
DESCRIPTION OF PREFERRED EMBODIMENT~
Referring first to Fig. 1, there is ill~strated
a cordless hand held hot air hair dryer generally desi-
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gnated by reference mlmeral 10 and seen ins-talled on a
combined electric and fuel recharging unit 12. The hair
dryer 10 comprises a housing having a central portion
14 formed with side openings 16 for admitting air, a
tubular portion 18 extending forwardly of the central
portion 14 and defining an inner heating chamber 20 and
an end nozzle 22 for exhausting air, and a handle
portion 24 depending from the central portion 14.
Mounted inside the central portion are a motor 2~ and a
fan 28 driven by the motor 26 for passing the air through
the heating chamber 20, the motor 26 being powered by a
rechargeable battery 30 mounted in the handle portion 24
and connected to the motor 26 by the electrical wire 32,
as best shown in Fig. 2. An AC-DC converter/transformer
34 also mounted in the handle portion 24 is coupled to
the battery 30 for recharging same, the AC-DC converter/
transformer 34 bei.ng operative to convert AC current
supplied from an AC household power source to DC current
and to lower the voltage from normal household voltage to
the operating voltage of the battery 30.
The heating chamber 20 contains a hollow
cylindrical catalytic heater 36 extending coaxially with
the tubular portion 18 of the dryer housing for heating
the air blown by the fan 28 prior to exhausting through
the nozzle 22. A conduit 38 interconnects the catalytic
heater 36 with a fuel reservoir 40 defined in a pressure
vessel 42 arranged rearwardly of the central portion 14.
The reservoir 40 is adapted to contain vaporizable fuel
44 in a liquid state, such as butane. The catalytic
heater 36 comprises a catalyst member 46 provided with
an outer metallic screen 48 supporting the latter inside
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the heating chamber 20, the catalyst member 46 being
formed for instance of asbestos and platinum or palladium
to combust the fuel 44 supplied from the reservoir 40
via the conduit 38 and vaporiæed inside the catalytic
heater 36 by means of the vaporizing nozzle 50. Since
the catalytic heater 36 is closed at its outer end by
the catalyst member 46 and metallic screen 48 except
for a small aperture 52, the vaporized fuel is forced
through the catalyst member 46 to realize efficient
burning. A plurality of baffle elements 54 are provided
inside the heating chamber 20 for directing the air blown
by the fan 28 onto the catalytic heater 36 and increasing
the residence time of the air inside the heating chamber
20. An electrical igni.tion system is also provided for
initiating the combustion of the vaporized fuel, which
includes a pair of electrodes of opposite polarity with
one electrode 56 disposed adjacent the outer end of the
catalytic heater 36 and connected to the battery 30, the
other electrode being defined by the metallic screen 46
also connected to the battery 30, when energized, both
electrodes are operative to discharge an ignition spark
for initiating the combustion of the vaporized fuel. The
aperture 52, although not necessary, is preferred since
it aids in efficient ignition.
The hair dryer 10 further includes a manually
operated control device 58 mounted in the handle portion
: 24 and actuated by a single manually operable actuation
member 60, for controlling the amount of current applied
to the motor 26 and proportionally adjusting the flow of
fuel to the catalytic heater 36 to thereby regula~e the
temperature of the heated air in relation to the amount
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of air flow exhausted through the nozzle 22. As shown
in Fig. 3, the control device 58 comprises a rheostat 62
connected intermediate the motor 26 and the battery 30
via the electrical wire 64 (see Fig. 2) for varying the
amount of current applied to the motor 26 and a valve
66 arranged in the conduit 38 for varying the flow of
fuel to the catalytic heater 36. The actuator member
60 which i5 operatively connected to both the rheostat
62 and valve 66 is continuously movable along a recti-
linear path between a lower limit position shown in
broken line and an upper limit position whereby to
increase the amount of current applied to the motor 26
when the actuator member 60 is moved in a direction toward
the upper limit position or to decrease the amount of
current when the actuator member 60 is moved in a direc-
tion toward the lower limit position while correspondingly
increasing or decreasing the flow of fuel to the catalytic
heater 36 to thereby provide heated air having a sub-
stantially constant temperature independently of the
amount of air flow exhausted through the nozzle 22.
As shown in Figs. 3-5, the rheostat 62 comprises
an elongated resistor element 68 and an electrically
conductive sweeping arm 70 in frictional sliding engage-
ment with the resistor element 68 for sweeping same, the
2~ arm 70 being fixedly connected to a shaft 72 which is
rotatably mounted to a pair of plate members 74 and 76
for permitting the arm 70 to sweep the resistor element
68 when the shaft 72 is rotated. The actuator member 60
is connected to the shaft 72 by means of a pin element 78
fixed to the actuator member 60 and extending through a
rectilinear slot 80 formed in the plate member 74, and
a lever 82 fixed at one end to the shaft 72 and formed
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with a longitudinally extending slot 84 receiving the
free end 86 of the pin element 78. The free end 86 of
the pin element 78 engages the slot 84 for sliding
movement therealong such that displacement of the actuator
member 60 causes the free end 86 to move along the slot
84 and the lever 82 to pivotally move and thereby rotate
the shaft 72, as best shown in Fig. 4. Such a pin and
lever connection thus converts the translational movement
of the actuator member 60 into a rotational movement for
rotating the shaft 72.
The valve 66, on the other hand, comprises a
valve body 88 having a fuel passageway 90 formed therein
~ a valvestem 92 also formed with a fuel passageway 90',
the valve stem 92 being movable in the valve body 88 and
biased by the coil spring 94, as shown in Fig. 6. A cam
disk 96 is fixedly mounted to the shaft 72 and frictionally
engages the stem 92 for moving same when the shaft 72 is
rotated in response to a displacement of the actuator
member 60 so as to adjustably restrict the fuel passage-
way 90,90' and thereby vary the flow of fuel to the
catalytic heater 36 via the conduit 38.
Fig. 7 schematically illustrates the circuit
used for varying the amount of current applied to the
motor 26 by means of the rheostat 62. As shown, the
rheostat 62 is also used for controlling the discharge
of an ignition spark between the metallic screen 48 of
the catalytic heater and the electrode 56. To this end,
the battery 30 i3 connected to the electrode 56 via the
rheostat 62 and to the metallic screen 48 via an amplifier
98 for increasing the voltage so as to provide the
necessary ignition spark. The resistor element 68 of
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the rheostat 62 has an end portion 100 which is
electrically insulated from the ~emainder thereof by an
insulating portion 102 and which corresponds to the
upper limit position of the actuator member 60. The
end portion 100 of the resistor element 68 is connected
to the electrode 56 such that when the actuator member
60 is at its upper limit position the circuit between
the metallic screen 48 and electrode 56 is closed to
discharge an ignition spark therebetween. At this
position, the valve 66 is also fully opened to permit
maximum flow of fuel to the catalytic heater 36. As
shown, the arm 70 of the rheostat 62 is biased by a
spring 10~ to move off the end portion 100 of the
resistor element 68 and to return to a position on the
resistor element 68 correspondin~ to substantially
maximum fan speed and maximum flow of fuel to the
catalytic heater 36.
Thus, the hair dryer 10 can be simply operated
by first moving the actuator member 60 to its upper
limit position so as to discharge an ignition spark
between the metallic screen 48 and the electrode 56 for
initiating the combustion of the fuel, and then releasing
the actuator member 60 so that it returns to a position
adjacent the upper limit position and corresponding to
substantially maximum fan speed and maximum flow of fuel
to the catalytic heater 36. Since the hair dryer 10 is
adapted to provide heated air having a substantially
constant temperature independently of the amount of air
flow exhausted through the nozzle 22, the flow rate of
heated air can thereafter be varied as desired by simply
moving the actuator member 60 between its lower and
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upper limit positions.
The hair dryer 10 can be conveniently recharged
with electricity and refilled with fuel by means of a
combined electric and Euel recharging unit 12 illustrated
in Fig. 1. As shown, the recharging unit 12 comprises
a frame 106 for supporting the dryer 10 in an upright
position. The support frame 106 which can be advan-
tageously mounted to a wall 108 by means of screws 110
is formed at its upper end with a vertically extending
groove 112 having a T-shaped cross-section for receiving
a corresponding flanged rib 114 provided rearwardly of
the pressure vessel 42 of the dryer, as best shown in
Figs. 8 and 9. The provision of such a rib and groove
enables the dryer 10 to be retained in the upright posi-
tion while allowing free vertical displacement thereof.
As shown in Fig. 9, the groove 112 flares upwardly
whereas the rib 114 tapers downwardly at its lower end
in order to permit easy insertion of the rib into the
groove.
The recharging unit 12 further includes a
clip member 116 for holding a fuel container 118 having
at the upper end thereof a fuel discharge valve 120 in
an upright position with the fuel discharge valve 120
positioned in alignment with the refill valve 122 pro-
vided in the bottom wall of the pressure vessel 42 so
as to permit the stem 124 of the fuel discharge valve
120 to extend through the orifice 126 of the refill
valve 122 when both valves are engaged with one another.
The fuel container 118 is of the type having an inner
tube 128 connected to the fuel discharge valve 120 and
extending to the bottom of the container for allowing
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transfer of liquid fuel from the container into the
reservoir 40 of the pressure ves.sel 42. An electri-
cal female plug 130 is movably mounted in the base of
the support frame 106 for limited vertical displace-
ment be-tween upper and lower positions, the electri-
cal ~emale plug 130 being connectable to an AC
household power source by means of the electrical wire
132 and engageable with an electrical male plug 134
which is housed in the handle portion 24 of the dryer
and connected to the AC-DC converter/transformer 34.
The electrical femal.e plug 130 is formed with a shoulder
136 for engaging the bottom surface 138 of the handle
portion 24 and is upwardly biased by a coil spring 140
to the upper position.
lS The hair dryer 10 can thus be conveniently
recharged with electricity and refilled with fuel by
downwardly displacin~ the dryer 10 to a recharge and
refill position shown in broken line to cause elec-
trical connection between the electrical female and
male plugs 130, 134 and engagement of the fuel dis-
charge valve 120 with the refill valve 122 and by
maintaining the dryer 10 at the recharge and refill
position against the upward force exerted by the spring
140 for a period of time sufficient to allow the reser-
voir 40 of the dryer to be refilled with fuel 44. Upon
release of the dryer 10, the electrical female plug 130
is upwardly moved by the spring 140 to its upper posi-
tion to upwardly displace the dryer and thereby cause
disengagement of the fuel discharge valve 120 and refill
valve 122 from one another while maintaining the elec-
trical connection between the electrical female and
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male plugs 130, 134. In this manner, the battery 30
is maintained charged while accidental leakage be-
tween the refill valve and fuel discharge valve,
which otherwise could occur if the valves remained
engaged, is prevented.
