U.S. patent number 3,919,793 [Application Number 05/531,357] was granted by the patent office on 1975-11-18 for extra capacity steam iron.
This patent grant is currently assigned to General Electric Company. Invention is credited to Kaj Toft, Wendell C. Walker.
United States Patent |
3,919,793 |
Toft , et al. |
November 18, 1975 |
Extra capacity steam iron
Abstract
An electric steam iron having first and second steam generating
means for converting water into steam for selective dispersal
through primary and secondary ports in the soleplate of the iron.
The first steam generating means communicates only with the primary
ports through a primary plenum means, and the second steam
generating means communicates only with the secondary ports through
a secondary plenum means. Water supply means are provided for
selectively supplying water to said first and second steam
generating means such that water supplied to the first steam
generating means is discharged as steam only through the primary
ports and water supplied to the second steam generating means is
discharged as steam only through the secondary ports.
Inventors: |
Toft; Kaj (Upland, CA),
Walker; Wendell C. (Alta Loma, CA) |
Assignee: |
General Electric Company
(Bridgeport, CT)
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Family
ID: |
27026382 |
Appl.
No.: |
05/531,357 |
Filed: |
December 10, 1974 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
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424568 |
Dec 13, 1973 |
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Current U.S.
Class: |
38/77.83 |
Current CPC
Class: |
D06F
75/18 (20130101) |
Current International
Class: |
D06F
75/18 (20060101); D06F 75/08 (20060101); D06F
075/06 () |
Field of
Search: |
;38/77.83,77.5,77.8,77.81,77.82 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Lawson; Patrick D.
Attorney, Agent or Firm: Powers; George R. Cullen; John F.
Platt; Leonard J.
Parent Case Text
This application is a continuation-in-part of copending patent
application Ser. No. 424,568 for "Steam Iron," filed Dec. 13, 1973,
by Kaj Toft and Wendell C. Walker and assigned to the assignee of
this application.
Claims
What is claimed as new and is desired to secure by letters patent
of the United States is:
1. An extra capacity steam iron comprising:
a soleplate;
a heating element for heating said soleplate;
cover means on said soleplate;
said soleplate and said cover means defining therebetween primary
plenum means, secondary plenum means independent of said primary
plenum means, first steam generating means communicating with said
primary plenum means, and second steam generating means independent
of said first steam generating means communicating with said
secondary plenum means;
and supply means for selectively supplying water to said first
steam generating means and for selectively supplying water to said
second steam generating means,
said soleplate having a plurality of primary ports therethrough
communicating only with said primary plenum means such that water
supplied to said first steam generating means is converted to steam
and discharged from the iron through said primary ports, and said
soleplate having at least one secondary port therethrough
communicating only with said secondary plenum means such that water
supplied to said second steam generating means is converted to
steam and discharged from the iron through said secondary port.
2. An extra capacity steam iron as defined by claim 1 in which said
second steam generating means comprises a soleplate boiler chamber
and a circuitous passage means connecting said soleplate boiler
chamber and said secondary plenum means.
3. An extra capacity steam iron as defined by claim 2 in which said
secondary plenum means comprises a pair of plenums disposed
symmetrically with respect to the longitudinal centerline of said
soleplate and at least one secondary port communicates with each of
said plenums, said circuitous passage means being disposed
symmetrically about the longitudinal centerline of said
soleplate.
4. An extra capacity steam iron as defined by claim 2 in which said
first steam generating means includes a soleplate boiler chamber,
said soleplate boiler chamber of said second steam generating means
being located forward of said soleplate boiler chamber of said
first steam generating means in the nose portion of said
soleplate.
5. An extra capacity steam iron as defined by claim 2 in which said
circuitous passage means crosses said heating element.
6. An extra capacity steam iron as defined by claim 2 in which said
first steam generating means includes a soleplate boiler chamber,
said soleplate boiler chambers of said first and second steam
generating means being located on opposite sides of said heating
element.
7. An extra capacity steam iron as defined by claim 6 in which said
heating element is imbedded within said soleplate and in which said
heating element is generally U-shaped with the open end of the U
facing the rear of the soleplate, said soleplate boiler chamber of
said second steam generating means being located forward of said
heating element in the nose portion of said soleplate.
8. An extra capacity steam iron as defined by claim 7 in which said
circuitous passage means crosses said heating element.
9. An extra capacity steam iron as defined by claim 2 in which said
second steam generating means is located within said primary plenum
means.
10. An extra capacity steam iron as defined by claim 2 in which
said soleplate has a substantially greater number of primary ports
communicating with said primary plenum means than secondary ports
communicating with said secondary plenum means and in which said
supply means is adopted to selectively supply water to said first
steam generating means at a substantially continuous metered rate
and to selectively supply water to said second steam generating
means for brief intervals of time at a momentary rate substantially
greater than the metered rate to said first steam generating means
such that steam discharged through said secondary ports has much
greater velocity and penetrating power than steam discharged
through said primary ports.
11. An extra capacity steam iron as defined by claim 10 in which
said first steam generating means includes a soleplate boiler
chamber for receiving water from said supply means, said soleplate
boiler chambers of said first and second steam generating means
being located on opposite sides of said heating element.
12. An extra capacity steam iron as defined by claim 11 in which
said heating element is generally U-shaped with the open end of the
U facing the rear of the soleplate, said soleplate boiler chamber
of said second steam generating means being located forward of said
heating element in the nose portion of said soleplate.
13. An extra capacity steam iron as defined by claim 12 in which
said circuitous passage means crosses said heating element.
14. An extra capacity steam iron as defined by claim 13 in which
said primary plenum means is disposed symmetrically with respect to
the longitudinal centerline of said soleplate and in which said
second steam generating means is located within said primary plenum
means.
15. An extra capacity steam iron as defined by claim 14 in which
said secondary plenum means comprises a pair of plenums disposed
symmetrically with respect to the longitudinal centerline of said
soleplate and at least one secondary port communicates with each of
said plenums, said circuitous passage means being disposed
symmetrically about the longitudinal centerline of said soleplate.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to electric steam irons and, more
particularly, to steam irons capable of producing a relatively
heavy steam flow of short duration.
2. Description of the Prior Art
Under certain ironing conditions, it may be desirable to supplement
the uniform steam flow of a conventional steam iron with a short
burst of relatively heavy steam flow. The extra steam generated in
the iron and dispelled in a short period of time through the ports
in the soleplate of the iron has much greater velocity and hence
penetrating power than the normal steam flow of the iron. As a
result, irons having extra steam capabilities are particularly
useful in ironing thick or multiple thickness fabrics or garments
in which stubborn wrinkles may be located beyond the penetrating
range of normal steam flow.
Steam irons having extra steam capability have been proposed and
built in the past, U.S. Pat. Nos. 3,599,357 to Gronwick; 3,711,972
to Risacher; and 3,828,452 to Eaton et al being illustrative of
various extra steam constructions. To produce a surge of extra
steam in steam irons, a relatively large quantity of water is
quickly introduced into a hot soleplate cavity or boiler, from
which it is directed through appropriate distribution passages to
the soleplate ports.
It is desirable that the extra steam be discharged with velocity as
high as possible in order to provide deep penetration into the
fabric being ironed.
SUMMARY OF THE INVENTION
It is therefore an object of this invention to provide an improved
iron construction for producing high velocity extra steam.
Another object of this invention is to provide an extra capacity
steam iron having improved steam generation means for producing
high velocity extra steam while assuring rapid and essentially
total conversion to steam of a relatively large quantity of water
rapidly injected into the steam generation means.
Briefly stated, in carrying out the invention in one form, an
electric iron having a soleplate with a heating element for heating
the soleplate is provided with cover means which cooperates with
the soleplate to define primary plenum means, secondary plenum
means independent of the primary plenum means, first steam
generating means communicating with the primary plenum means, and
second steam generating means communicating with the secondary
plenum means. The soleplate has a plurality of primary ports
therethrough communicating only with the primary plenum means and
at least one secondary port therethrough communicating only with
the secondary plenum means. Supply means are provided for
selectively supplying water to the first steam generating means and
for selectively supplying water to the second steam generating
means. During iron operation, water supplied to the first steam
generating means is converted to steam and is discharged from the
iron only through the primary ports, and water supplied to the
second steam generating means is converted to steam and is
discharged from the iron only through the secondary ports. By a
further aspect of the invention, there are a substantially greater
number of the primary ports than secondary ports, and the supply
means is adapted to selectively supply water to the first steam
generating means at a substantially continuous metered rate and to
selectively supply water to the second steam generating means for
brief intervals of time at a momentary rate substantially greater
than the metered rate to the first steam generating means. In this
manner, steam discharged through the smaller number of secondary
ports has much greater velocity and penetrating power than steam
discharged through the greater number of primary ports.
By still further aspects of the invention, the second steam
generating means comprises a soleplate boiler chamber and a
circuitous passage means connecting the soleplate boiler chamber
and the secondary plenum means. To provide rapid and essentially
total conversion of the relatively large quantity of water rapidly
injected into the soleplate boiler chamber, the circuitous passage
means crosses the heating element. The first steam generating means
also includes a soleplate boiler chamber and the boiler chambers of
the first and second steam generating means are located on opposite
sides of the heating element. The heating element is preferably
U-shaped, and the soleplate boiler chamber of the second steam
generating means is located forward of the U-shaped heating element
in the front portion of the soleplate.
BRIEF DESCRIPTION OF THE DRAWINGS
While the novel features of the invention are set forth with
particularity in the appended claims, the invention, both as to
organization and content, will be better understood and
appreciated, along with other objects and features thereof, from
the following detailed description taken in conjunction with the
drawings, in which:
FIG. 1 is an elevation view of the front portion of an electric
steam iron incorporating the present invention, the lower portion
of the iron being shown in cross-section and the upper portion of
the iron illustrating internal iron components by broken lines;
FIG. 2 is a view of the upper surface of the soleplate of the iron
taken along viewing line 2--2 of FIG. 1; and
FIG. 3 is a view of the coverplate of the iron taken along viewing
line 3--3 of FIG. 1, the location of the heating element and the
ports in the soleplate relative to the coverplate being illustrated
by broken lines.
DETAILED DESCRIPTION
As shown by FIGS. 1 and 2, an iron indicated generally by the
numeral 10 includes a flat soleplate 12 having a smooth flat lower
ironing surface 14 and a substantially flat upper deck 16. The
soleplate 12 has a pair of cavities 18 and 20 therein opening
upwardly to the upper deck 16. The purpose of the cavities 18 and
20 will become obvious as this description proceeds. A plurality of
primary ports 22 and a smaller plurality of secondary ports 23 are
provided in the soleplate 12 extending from the upper deck 16 to
the ironing surface 14. In accordance with conventional practice,
soleplate 12 may be made from a suitable material such as cast
aluminum with an electrical loop or U-shaped heating element 24
cast in position. This heating element preferably is of the sheath
type and, with an electrical resistance element, extends through an
outer tubular protective sheath with the heating element separated
from the outer sheath by an insulating compound resistant to heat
such as granulated and compressed magnesium oxide. As illustrated
by broken lines in FIG. 2, the heating element generally extends in
a U-shaped loop beginning at the rear of the iron and along one
side to the front generally pointed portion of the soleplate and
then rearwardly along the other side such that the open end of the
U faces the rear of the soleplate. Thus, substantially uniform heat
distribution is provided in the soleplate 12 when the iron is
plugged in and activated.
Referring now to FIGS. 1 and 3, a coverplate 30, which may also be
made of a suitable material such as die cast aluminum, is mounted
on the upper deck 16 and is secured to the soleplate 12 by suitable
fastening means such as the illustrated machine screw 32 passing
through openings 34 in the coverplate 30 and into threaded bores 36
in the soleplate 12. Unlike the substantially flat soleplate 12,
the coverplate 30 is provided as best illustrated by FIGS. 3 and 4
with a large number of depending walls which cooperate with the
essentially flat deck 16 of the soleplate 12 (and the cavities 18
and 20 therein) for forming a number of chambers, passages, and
plenums therein. More particularly, the coverplate 30 includes a
peripheral wall 38 which extends around the entire boundary of the
coverplate 30 and seats against the flat deck 16 of the soleplate
12 to prevent leakage therebetween. If the seal provided by the
mating wall 38 and the soleplate 12 is insufficient in practice, an
appropriate sealant may be applied to the peripheral joint between
the soleplate and the coverplate to further prevent leakage.
Still referring to FIGS. 1 and 3, the iron 10 further includes a
water tank 40 mounted above and substantially coextensive with the
coverplate 30. A metering valve generally indicated by the numeral
42 is provided in the bottom of the water tank 40 directly above
the cavity 18, the lower portion of the valve 42 extending
downwardly from the water tank 40 through an aligned opening 44 in
the coverplate 30. The water valve 42 has a relatively small
orifice 46 therein through which water may drip from the water tank
40 into the cavity 18 at a metered rate selected for substantially
continuous conversion of water into steam. If desired, the iron may
be used in a dry mode by depressing button 48 on the iron handle 50
until locking surface 52 thereon engages a mating surface (not
shown) on the handle 50 to hold the button 48 in its depressed
position. When the button 48 is depressed, stem 54 attached thereto
is moved downwardly until its reduced diameter lower end portion 56
moves into the metering orifice 46 to seal the orifice, thus
preventing the entry of additional water into the cavity 18. To
prevent escape of steam from the cavity 18 upwardly around the
water tank 40, walls 58 surround the water valve 42 and are sealed
with respect to both the tank 40 and the upper surface 59 of the
coverplate 30.
A diaphragm pump 60 is located above the water tank 40 in the front
portion of the handle 50 with a water inlet tube 62 depending
therefrom into the tank 40. A water outlet tube 64 connects the
diaphragm pump 60 with the cavity 20 in the front portion of the
soleplate 12, the lower end of the tube 64 being tightly received
in an opening 66 in the coverplate 30. The diaphragm pump 60 is
operated by a pushbutton 68 on the iron handle 50. When the button
68 is depressed, a measured quantity of water from the tank 40 is
drawn up the tube 62 past a ball check valve 70 and then ejected
through the outlet tube 64 into the cavity 20 in the soleplate 12.
In this manner, water is injected into the cavity 20 for only brief
intervals of time at a momentary rate greater than the rate at
which water can be metered through the orifice 46 of the valve 42.
In accordance with the unique arrangement of chambers and passages
provided by the soleplate 12 and the coverplate 30, the amount of
water supplied by the pump 60 may be maximized without substantial
risk of incomplete vaporization and water spotting. The diaphragm
pump 60 will not be further described since various pump
arrangements may be used to supply water to the cavity 20. As an
example, the diaphragm pump structure disclosed by U.S. Pat. No.
3,183,611 to Alfred G. Swenson may be used in connection with the
present invention.
The iron 10 also includes a temperature selector 71 which through
appropriate control apparatus (not illustrated) controls the
energization of the heating element 24 when the iron is connected
to a source of electric power to maintain the temperature of the
soleplate 12 at a selected temperature.
Referring now to FIGS. 1 through 3, the soleplate 12 and the
peripheral wall 38 and interior walls including walls 72 and 82 of
the coverplate 30 cooperate to form primary plenum means including
a plenum 76 along the upper edge of the iron as illustrated by FIG.
3 and a plenum 80 along the lower edge of the iron as illustrated
by FIG. 3. The plenum 76 communicates with the primary ports 22 in
the lower portion of the soleplate 12 as illustrated by FIG. 2 such
that steam supplied to plenum 76 will in turn be delivered to the
primary ports 22 and ejected through the primary ports 22.
Similarly, the plenum 80 communicates with the primary ports 22 in
the upper portion of the soleplate 12 as illustrated by FIG. 2. The
primary plenum means is thus symmetrically disposed with respect to
the longitudinal centerline of the soleplate 12. Walls 38, 84 and
86 of the coverplate 30 cooperate with the deck 16, the cavity 18
and the walls 58 between the coverplate 30 and the tank 40 to form
a first steam generating means in which water metered through the
orifice 46 is flashed into steam in the cavity 18 and then
delivered through the passages 88 and 90 to the plenums 76 and 80,
respectively of the primary plenum means. This first steam
generating means is essentially a conventional steam generator of
the flash boiler type, the cavity 18 being conventionally referred
to as the "boiler" of the iron. Since water is essentially
continuously metered into the cavity or soleplate boiler chamber 18
at a relatively slow rate at which the heating element 24 and the
heat it transmits to the soleplate 12 can readily convert the water
to steam, the passages 88 and 90 and boiler itself can be of
relatively simple construction. Since there are a large number of
primary ports 22 and water is continuously metered into the
soleplate boiler chamber 18 at a relatively slow rate, the steam
generated in the first steam generating means is discharged through
the primary ports 22 in the relatively gentle manner desired for
normal ironing applications.
In accordance with the present invention, a secondary plenum means
is provided, the secondary plenum means including a pair of plenums
130 and 132 symmetrically disposed with respect to the longitudinal
centerline of the soleplate 12. As illustrated by FIG. 3, the
plenum 130 is located inboard of the primary plenum 76 and is
formed between the soleplate and the coverplate by depending
coverplate walls 72 and 84. The plenum 130 communicates with the
secondary ports 23 in the lower portion of the soleplate 12 as
illustrated by FIG. 2 such that steam supplied to the plenum 130 is
ejected through the relatively small number, in this case, two, of
secondary ports 23. Similarly, the secondary plenum 132 is formed
inboard of the primary plenum 80 by coverplate walls 82 and 86. The
plenum 132 communicates with the secondary ports 23 in the upper
portion of the soleplate 12 as illustrated by FIG. 2 such that
steam supplied to the plenum 132 is ejected through the relatively
small number of secondary ports.
As best illustrated by FIGS. 1 and 3, a second or extra steam
generating means includes a soleplate boiler chamber 100 formed by
the soleplate 12 including the cavity 20 and the coverplate 30. The
soleplate boiler 100 of the second steam generating means is
located forward of the U-shaped heating element 24 and the
soleplate boiler 18 in the front or nose portion of the iron, and a
passage 102 extends rearwardly from the relatively large chamber
100 across the heating element 24 to a pair of expansion chambers
104 and 106, the passage 102 and the expansion chambers 104 and 106
also being formed by the upper deck 16 of the soleplate 12 and
walls depending from the coverplate 30. More particularly, the
passage 102 is a converging-diverging passage partially defined by
walls 108 and 109, and the expansion chambers 104 and 106 are
partially defined by curved walls 110 and 112, respectively. A
passage 114 connects the expansion chamber 104 and the plenum 130,
the passage 114 being defined by coverplate walls 108, 116, and 72
in cooperation with soleplate deck 16. A similar passage 118
symmetrically disposed with respect to the passage 114 and the
longitudinal connects the expansion chamber 106 and the plenum 132,
the passage 118 being defined by coverplate walls 109, 120 and 82
in cooperation with the soleplate deck 16. The upstream ends of the
passages 114 and 118 are substantially parallel with the downstream
end of the passage 102 such that steam and water passing through
the chambers 104 and 106 is turned through approximately
180.degree.. It will thus be seen that the passages 102, 114 and
118 and the expansion chambers 104 and 106 comprise circuitous
passage means interconnecting the soleplate boiler 100 and the
plenums 130 and 132 of the secondary plenum means.
A rib 126 is provided across the throat portion of the
converging-diverging passage or nozzle 102 to further restrict its
flow area and to deflect water and steam passing therethrough
downwardly against hot deck 16 of the soleplate 12. A plurality of
similar ribs 128 are provided in each of the passages 114 and 118
to provide flow restrictions and to further deflect water and steam
flowing therethrough downwardly against the hot deck 16 of the
soleplate 12.
When it is desired to provide extra steam (whether or not the
orifice 46 is open and supplying water to the first steam
generating means), the button 68 on the handle 50 is pumped once,
and a measured amount of water is drawn up the inlet tube 62 and is
discharged from the diaphragm pump 60 through the outlet tube 64
into the cavity 20 and the expansion chamber 100. Since the chamber
100 is adjacent the heating element 24 and is relatively large, the
water injected into the chamber 100 absorbs heat from the soleplate
12, partially vaporizes and expands within the chamber 100 until
the pressure builds up to a level sufficient to force the partially
vaporized water out of the expansion chamber 100 and through the
circuitous passage means comprising the nozzle 102, the expansion
chambers 104 and 106, and the passages 114 and 118 to the
symmetrically disposed secondary plenums 130 and 132.
Since there are a relatively small number of secondary ports 23 and
water is injected into the soleplate boiler chamber 100 for only
brief intervals of time at a momentary rate greater than the rate
at which water is metered into the first steam generating means,
the steam generated in the second steam generating means is
discharged through the secondary ports 23 at much higher velocity
than that discharged from the primary ports 22. The extra steam
discharged through the secondary ports 23 is thus particularly
adapted for use in fabrics requiring deep penetrating steam for
deep down wrinkles and the like.
As illustrated by FIG. 3, the soleplate boilers 18 and 100 of the
first and second steam generating means are preferably positioned
on opposite sides of the heating element 18 in order to promote
rapid and efficient use of the heat transferred to the soleplate 12
in the generation of normal and extra steam. To further enhance
heat transfer to the relatively large quantity of water injected
into the boiler chamber 100, the circuitous passage means leading
from the chamber 100 to the secondary plenums 130 and 132
preferably crosses or extends over the heating element 118 at one
or more points to assure rapid heat transfer from the heating
element to the vaporizing water. In the illustrated embodiment of
the invention as illustrated by FIG. 3, the second steam generating
means and the secondary plenums 130 and 132 are located inboard of
the primary plenums 76 and 80, a portion of the inner walls 72 and
82 of the primary plenums 76 and 80 forming an outer wall of the
plenums 130 and 132.
From the foregoing, it will be seen that this invention provides an
improved iron construction for providing high velocity extra steam
while simultaneously assuring rapid and essentially total
conversion to steam of a relatively large quantity of water rapidly
injected into the steam generating means. This is accomplished by
utilizing totally independent steam generating means for the extra
steam and discharging the extra steam through a limited number of
soleplate ports used only for the delivery of extra steam.
While the invention has been particularly shown and described with
reference to a preferred embodiment thereof, it will be understood
by those skilled in the art that various changes in form, details,
and application may be made therein without departing from the
spirt and scope of the invention. For example, while two secondary
ports 23 have been shown in communication with each secondary
plenum, it will occur to those skilled in the art, more or less
ports could be used depending upon the discharge velocity desired.
Also, although the various chambers and passages as illustrated are
symmetrically disposed with respect to the longitudinal centerline
of the soleplate, it will be obvious that a symmetrical arrangement
is not required for the practice of the present invention in its
broader aspects. Accordingly, it is intended that all such
modifications and changes be included within the scope of the
appended claims.
* * * * *