Note: Claims are shown in the official language in which they were submitted.
THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. An electric appliance comprising; a polypropylene
container body having a bottom rim defining a circular aperture
of predetermined radius, an electrical heating means including
a heating element adapted to fit within the container, terminals
and an external electrical power source, a circular metal plate
having a circumference of a radius greater than the radius of
the aperture, said plate having a groove around its circumference
adapted to receive the rim in a snug press fit connection to
seal the aperture, said plate supporting the element within
the container and permitting the terminals to extend through
the plate to make electrical connection with the external power
source, in which said plate is made of a soft copper material
having a rampart portion bending away from said groove at an
angle and extending a short distance towards a central portion
of the plate, said rampart portion being adapted to permit deflection,
expansion and contraction of the plate during heating and cool mg
while maintaining the snug connection between the rim and the
groove.
2. The invention defined by Claim 1 wherein the copper
material is substantially pure copper.
3. The invention defined by Claim 1 wherein the copper
material is brass having a mixture in the range of 70% or more
copper with 30% or less zinc, respectively.
4. The invention defined by Claim 1 in which the copper
material is brass having a mixture in the range of 80% or more
copper with 20% or less zinc respectively.
5. The invention of Claims 2, 3 or 4 in which the copper
material is dead soft.
6. The invention defined by Claim 1 in which the copper
material is brass being about 85% copper and 15% zinc.
7. The invention of Claim 6 in which the brass is dead
soft.
8. The invention defined in Claims 1, 2 or 3 where the
electrical heating means has a power output of greater than
500 watts.
9. The invention defined in Claims 1, 2 or 3 in which
the power output of the electrical heating means is greater
than 1000 watts.
10. The invention defined in Claims 1, 2 or 3 where the
power output of the electrical heating means is about 1500 watts.
11, The invention defined in Claim 1 having a shoulder
about the outside of the rim to provide increased strength against
radial deflection.
12. The invention defined by Claim 11 in which the groove
of the metal plate has an outside peripheral flange adapted
to fit under said shoulder.
13. The invention defined by Claims 11 and 2.
14. The invention defined by Claims 11 and 3.
15. The invention defined by Claims 11 and 4.
16. An electrical appliance comprising, a polypropylene
container body having a bottom rim defining a circular aperture
of predetermined radius and having an integral shoulder slightly
above the aperture outside the rim, an electrical heating means
including a heating element adapted to fit within the container,
terminals and an external electrical power source, said heating
means having a power greater than 1000 watts, a circular metal
plate of a soft copper material having a circumference of a
radius greater than the radius of the aperture, said plate
having a flange around its circumference adapted to fit under
said shoulder, having, next within a groove adapted to fit
about the rim in a snug press fit connection and having, next
within, a rampart portion bending away from the groove inside
the rim at an angle between 20° and 70° from a horizontal
plane towards a central portion of the plate for a short
distance to permit expansion and contraction of the plate
during heating and cooling while maintaining the snug
connection between the rim and the groove, said central
portion of the plate supporting the element within the
container and permitting the terminals to extend through
to make electrical connection with the external power source.
17. The invention of Claim 16 in which the copper
material is substantially pure copper.
18. The invention of Claim 16 in which the copper material
is brass having a mixture range of 80% or more copper with
20% or less zinc.
19. The invention of Claim 16 in which the copper material
is brass having a mixture of about 85% copper and 15% zinc.
The invention of Claims 17, 18 or 19 in which the
copper material is dead soft.
21. The invention of Claims 17, 18 or 19 in which the
angle of the rampart portion is between 25° and 65° from a
horizontal plane.
22. The invention of Claims 17, 18 or 19 in which the
copper material is dead soft and the angle of the rampart
portion is between 25° and 65° from a horizontal plane.
23. An electrical kettle comprising, polypropylene
container body having a bottom rim defining a circular aperture
of a radius between 8 and 10 inches and having an integral,
peripheral shoulder slightly above the aperture outside the
rim, an electrical heating means including a heating element
adapted to fit within the container, terminals, a thermostat
and an external power source, said heating means having a power
greater than 1000 watts, a circular metal plate of a soft copper
material of a radius greater than the radius of the aperture
but within the shoulder, said plate having a flange around
its circumference adapted to fit under said shoulder, having
next a groove adapted to fit about the rim in a snug press
fit connection and having next a rampart portion bending
away from the groove inside the rim at an angle in the range
of 25° to 65° from the horizontal towards a central portion
of the plate for a distance in the range of 0.5 to 1 inches,
the central portion being flat thereafter to an upward cup-
shaped indentation adapted to contain the thermostat, said
plate supporting the element within the container and per-
mitting the terminals to protrude through the plate to con-
nect to the external power source and permitting the thermostat
to protrude through to the element.
24. The electric kettle of Claim 23 in which the rim
depends vertically downward from the bottom of the aperture,
curves under, out and upwards into an indentation above the
bottom of the rim and beneath the shoulder, and in which the
flange of the metal plate is adapted to fit under the
shoulder and the groove is adapted to fit in a snug press
fit connection into the said indentation, around the underside
of the rim and up inside the rim to a position near the top
of the shoulder, and in which the rampart portion slants
downward from the groove inside the rim at an angle from
the horizontal of between 25° and 50°.
25. The electric kettle of Claim 24 in which the copper
material is dead soft copper.
26. The electric kettle of Claim 24 in which the copper
material is dead soft brass.
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27. The electric kettle of Claim 24 in which the copper
material is dead soft brass in the range of 80% copper or
more to 20% zinc or less.
28. The electric kettle of Claim 24 in which the copper
material is soft brass of about 85% copper and 15% zinc.
29. The electric kettle of Claim 24 in which the copper
material is dead soft brass of about 85% copper and 15% zinc.
30. An electrical kettle comprising, a polypropylene
container body having a bottom rim defining a circular
aperture of a diameter between 8 and 10 inches, said rim having
a first portion within the aperture, a second portion curving
from within the aperture to outside the aperture, a third
portion extending upwards and into a neck portion, and said
body having an integral, peripheral shoulder with a flat
underside encircling the body next above the neck, an elec-
trical heating means including a heating element adapted to
fit within the container, a thermostat, terminals and an
electrical power source, said electrical heating means having
a power greater than 1000 watts and being adapted to heat
water within the kettle, a circular soft metal plate of a
soft copper material of a radius greater than the radius of
the aperture but within the shoulder, said plate having an
integral flange about its circumference adapted to fit against
the underside of the shoulder, said metal plate having next
within said flange, an integral groove adapted to fit in snug
press fit connection about the neck, the third portion, the
second portion, the first portion of the rim and up within the
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aperture to a position opposite the shoulder above the neck
portion, said metal plate having, next within said groove,
an integral rampart portion downwardly depending from the
groove inside the rim of the aperture at an angle in the
range of 25° - 50° from the horizontal over a horizontal
distance of between 0.5 to 1.0 inches, being adapted to help
secure the snug fit of the groove about the rim during heat-
ing and cooling, said metal plate having, next within said
rampart portion, a flat horizontal portion adapted to permit
location of the terminals for the element and the like, said
metal plate having, next within the flat horizontal portion,
an indentation adapted to receive a thermostat for control
of the power source, said metal plate being adapted to seal
the aperture about the rim and to provide a support for the
electrical heating means.
31. The electrical kettle of Claim 30 having a bowl
shaped based under the shoulder and the metal plate and
attached to said plate, said bowl being adapted to provide
a base for the kettle and to cover the metal plate, the
terminals and the thermostat.
32. The electrical kettle of Claim 30 wherein the soft
copper material is brass being about 85% copper and 15% zinc.
33. An electric kettle comprising a polypropylene body
that is closed at the bottom by a metal sheet, the body having
at the bottom a peripheral generally cylindrical lip and
spaced upwardly from the bottom edge of the lip, a peripheral
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outwardly extending ridge, with a peripheral indentation
in the outer surface of the lip below the ridge, the metal
sheet comprising a sheet of soft copper with a circular in-
verted peripheral channel one side of which fits snugly
against the inside of the lip and continues, in snug engage-
ment, with the lip, under the lip and then upwardly into
the peripheral indentation of the lip, the channel permitting
deflection, expansion and contraction of the central portion
of the sheet without relaxing the engagement of its periphery
with the lip whereby a water-tight seal is provided between
the body and the body and the sheet.
34. A kettle as claimed in Claim 33, including a metal
cup-shaped base having an upper peripheral edge engaging
the outwardly extending ridge, the base and said sheet being
fastened together at the central portion of the sheet.
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