US3103079A

US3103079A - Steam iron

Info

Publication number: US3103079A
Application number: US181056A
Authority: US
Inventors: Samuel R Bricker; Alan D Smith
Original assignee: Westinghouse Electric Corp
Current assignee: CBS Corp
Priority date: 1962-03-20
Filing date: 1962-03-20
Publication date: 1963-09-10
Anticipated expiration: 1980-09-10

Description

Sept. 10, 1963 s. R. BRCKER ETAL STEAM IRON l Filed MalOh 20, 1962 'y/ a6 l 4e I4 Z; t g 'a7 l FI[\| o '9 l 8 1Q 2| w 23 3 l an D. 5m; Iz

United States Patent O 3,103,079 STEAM IRON Samuel R. Bricker, Shelby, and Alan D. Smith, Mansfield, Ohio, assignors to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Filed Mar. 20, 1962, Ser. No. 181,056 3 Claims. (Cl. 3877) This invention relates to steam irons of the flash type, more particularly to such an iron in which the reservoir for water is not in free or unrestricted communication directly with the atmosphere.

The object of the invention is to provide as uniform as possible .flow of water yfrom the reservoir to the steam generating chamber, and consequent uniform rate of steam generation, under the varying conditions encountered by the steam iron, including the ironing position in which the discharge of steam from the ports is restricted by the material being ironed, and the raised position of the iron in which it steams freely, and also the various levels of water in the reservoir.

A further and more particular object is to provide such uniformity of water ilow and steam generation using a valve orice or opening of a practical size, such as .032 to .035 of an inch diameter, to control the flow of water from the reservoir to the steam generating chamber.

In many dash-type steam irons, an electrically heated steam generating chamber is provided in the soleplate of the iron and water is fed thereto by gravity from a reservoir above the steam generating chamber. A drip valve controls this tlow of water to the steam generating chamber, and the ilow passage is of suthciently small diameter to limit the iiow to separate and intermittent droplets, each droplet Aflashing to steam as it hits the hot bottom of the steam generating chamber.

To prevent water in the reservoir splashing out through the till opening of the reservoir during ironing, it is common practice to provide a fill valve which completely closes the 4till opening during ironing operations. This necessitates the provision of a vent tube to permit entry of air to the reservoir to replace the water as the latter is gradually fed to the steam generating chamber.

It is desirable that the valve flow passage or opening be of a large enough diameter that it can be machined accurately in a practical manner, and also that it does not clog readily. An opening of .032 to .035 of an inch diameter has been found satisfactory for these purposes. However, upon using an opening of this large diameter with a vent tube communicating at its upper end with the water reservoir and at its lower end directly with the steam generating chamber, it was found that the ow of water was excessive, presumably because of the high steam pressure communicated through the vent tube from the steam generating chamber to the water reservoir.

In accordance with the present invention, this vent tube, or pressure equalizing tube as it is sometimes referred to, provides communication between a region at the top of the reservoir above the water level therein, and a region of a steam flow passage connecting the steam generating chamber with a plurality of orifices in the bottom of the soleplate, which orifices discharge steam, generated in the chamber, to the material being ironed. This region of the steam flow passage with which the vent tube communicates is somewhat upstream of the discharge orifices, but closer to the latter than to the steam generating chamber. Particularly, this region is one where the maximum steam pressure is closer to that which occurs adjacent the inlets to the orices than to that which occurs in the steam generating chamber.

3,103,079 Patented Sept. 10, 1963 With the above arrangement, both the maximum pressure and the average pressure in the reservoir above the body of water therein will be less than the corresponding pressures in the steam Igenerating chamber. The pressure in the steam generating chamber is imposed on the under side of the drip valve, resisting gravitational ilow of Water therethrough, and since this pressure is greater than the pressure in the reservoir above the water, the water iiow rate through -the drip valve is less than it would be if gravitational forces only were involved. Thus, the desired lflow is effected without undesirable restriction of the ilow passage through the drip valve.

In the general arrangement of parts herein illustrated, which arrangement is popular today, the vent tube is relatively close to the steam `generating chamber, due to the practice of locating the manually operable elements of all the controls in the front post of the iron handle. Consequently, the steam flow passage tends to be so short that little pressure drop occurs between the steam generating chamber and the entrance to the steam discharge orifices, unless a special restriction is provided in accordance with the present invention. As illustrated, one or more bai-lies or walls are interposed in the steam ow passage, increasing the effective length thereof and/ or providing one or more restrictions, thus producing an additional pressure drop.

The invention and the advantages thereof will be apparent from the following description and claims taken in connection with the accompanying drawing, forming a part of this application, in which:

FIG. l is a `'fragmentary side elevational view, partially in section, of an iron constructed in accordance with the present invention; FIG. 2 is a transverse sectional view, taken along the lines II-Il of FIG. l, looking in the direction indicated by the arrows; and

FIG. 3 is a horizontal sectional View, taken along the lines III- Ill of FIG. l, looking in the direction indicated by the arrows.

In the drawings, the reference character 10 indicates a steam iron of the flash type previously described and including a soleplate 11, a reservoir 12 for water positioned in spaced overlying relation to the soleplate, a shell 13 which, in cooperation with the soleplate, encloses and houses the reservoir 12, and a handle member 14 including at least a front post 16. If desired, the handle may also include the usual rear post, although the latter is not necessary in practicing the present invention.

The reservoir 12 has an uptstanding neck portion' 17 received in a downwardly facing recess `1S in the lower end of the front handle post 16. The upper edge of the reservoir neck 17 is sealed, by any suitablel compressible gasket 19, with respect to the flat downwardly-facing surface 21 of the recess 18. An opening or passage 22 is provided in the handle post 16, this passage opening throu-gh the surface 21, inwardly of the sealing gasket 19, `and also opening outwardly at the front of the post 16. Consequently, when the iron is tilted to ian upright position, with the front portion of the passage 22 in a vertical position, water may 'be poured through the passage 22 into the interior of the reservoir 12. In order to prevent splashing of water from the reservoir out through the ll passa-ge 22 during use of the iron, there is provided a closure kdisc 23 for closing the ll passage 22 under all conditions except actual lilling of the reservoir. This disc 23 is freely movable longitudinally on and with respect to la valve rod 26 extending vertically through the reservoir 12. However, the closure valve disc 23 is biased into closing position against its seat, which is a portion of the dat wall 21 of the recess 18.

3 This biasing is effected by a compression spring 24 which surrounds the valve rod Z6 below the disc and is maintained under compression =by engagement with a washer 25 fixed on the Irod 26.

The lower end of the rod 26 constitutes la closure valve which cooperates with a valve seat 2S at the upper end of la flow passage 29 `formed through an insert 31 which extends from above the bottom wall of the reservoir to and thro-ugh a cover plate 32 which overlies and is cemented to, or otherwise held in tight engagement with, the top of the solepl'ate 11. The passage 29 provides for limited flow of water from the reservoir 12 to a steam generating chamber 33 formed in the soleplate immediately Ibelow the passage 29. When' the valve 27 and its stem or rod 29 are in -a raised position, water passes intermittently to the steam generating chamber 33 where it immediately ashes into steam.

An electric heating element 34, preferably of the sheathed type, is disposed in the soleplate in close proximity to the steam generating chamber, so that the bottom wall thereof is maintained at -a sufficiently high ternperature to insure instantaneous flashing to steam of each ydrop of water as it falls thereonto from the reservoir. As previously explained, the drip passage 29 is of suhciently small diameter that the water passes therethrough in separate and individual drops, even when the valve is fully open.

As best shown in FIGS. 1 and 3, the cover plate 32 is provided with sa plurality of downwardly-facing ribs or wall elements which are sealed against the top surface off the soleplate and cooperate therewith to provide chambers and passages best shown in FIG. 3. From consideration of the latter figure, it will be apparent that the steam generating chamber 33 is defined by, in addition to the cover plate and the soleplate, an H-shaped'wall stnucture 35 and a V-shaped wall structure 36, the two being spaced slightly to provide exits 37 for steam generated in the chamber. It will be apparent that these exits 37 constitute restrictions in the path of flow of steam from the steam generating chamber 33 to a plurality of steam [discharge orifices 3S provided in the soleplate 11 and through which steam is discharged through the bottom surf-ace of the soleplate to whatever material `is being ironed.

The flow path of steam from the generating chamber 33 to the orifices 38 is indicated by the arrows in FIG. 3, and it will be apparent that a fairly long fiow path is provided, even though the steam generating chamber is relatively close to the exhaust or discharge orifices 38. This elongated passage arrangement may be desirable for the reasons previously discussed, particularly in irons of the type herein illustnated, utilizing the presently popular arrangement Where the manual controls for the various valves are 'disposed in or at the front post of the handle. In many earlier iron designs, the control for the drip valve was disposed in the space between the front and rear posts of the handle, and hence the drip valve, which was usually directly below the control valve, was disposed near or to the rear of the center of the iron, considered in la front-to-rear direction.

In order to prevent entry of water from the reservoir into the vent tube 41, it is desirable to locate the upper end of this tube within the neck 17 of the reservoir, where it is least likely to be subject `to the entry of Water due to movement of the iron during ironing. This results in the vent tube yand the drip valve being located in very close proximity to each other, with the result that, were it not for the utilization of the present invention, the lower end of the vent tube would receive steam at a pressure substantially the same as that existing in the ste-am generating chamber, with the result that the pressure in the upper portion of the reservoir would be substantially equalized with that in the steam generating chamber. However, as previously discussed, in order to have the 4 drip passage 29 of maximum diameter, it is desirable to have the pressure above the water in the reservoir equalized with a pressure somewhat lower than that existing in the steam generating chamber, and this result is produced -by the herein illustrated invention.

Referring fagain to FIG. 3, it will be noted that the lower end of the vent tube 41 (indicated by the dotted line 41a in FIG. 3) extends into a region 42 which is separated from the steam generating chamber 33 by the V-shaped wall structure 36. To further isolate the region 42 in which the lower end ofthe vent tube is located from the steam flowing to the discharge orifices 38, a second V-shaped wall structure 43 is disposed in' somewhat spaced relation to the first-mentioned V-shaped wall structure 36, with these two wall structures dispose-d lat opposite sides of the re-gion 42. v

A portion of the steam flowing to the exhaust orifices 38 passes between these Wall structures 36 and 43, and passes under the latter through grooves or recesses 44 formed in the upper surface of the soleplate near the region 42.

It will be apparent that the lower end of the vent tube 41 is subjected to a steam pressure which, while somewhat above that existing at the inlets to the exhaust orifices 38, is substantially below that existing in the steam generating chamber 33. Consequently, the upper portion of the reservoir 12, above the body of water therein, is likewise subjected to this same pressure which is intermediate that in the steam generating chamber and that at the discharge orifices.

The actual construction `and relationship of the fill opening closure valve 23 Iand the drip valve 27 forms no part of the present invention, being disclosed and claimed in copending application Serial No. 179,357, filed March 13, 1962, and vassigned to the assignee of the present application. However, it may be mentioned that there is provided, for vertical sliding movement in the front post 16 of the handle 14, a valve adjusting rod 46 whose upper end would be operatively associated with a manual adjusting or positioning member (not shown). The lower portion of this adjusting rod 46 carries a laterally-extending lug or arm 47 which slidably receives the valve stem or rod 26 and, when raised from the position shown in FIG. 1, engages the under side of a head l48 formed on the valve Vstem 26 to raise the latter and its valve member 27 from the valve seat 28 to open the drip Valve `and permit flow of water from the reservoir to the steam generating chamber.

When the adjusting rod 46 is moved downwardly from the position shown in FIG. l, its lower end will engage the disc closure valve 23 and tilt the latter to open the valve for filling or emptying of the reservoir.

For a more detailed description of the construction and operation of these two valves, reference should be had to the previously-identified copending application.

While the invention has been shown in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modications without departing from the spirit thereof.

We claim:

1. A steam iron including a soleplate having a steam generating chamber,

means for heating the soleplate in the region of said chamber,

a closed reservoir for w-ater above the soleplate,

means for supplying drops of Water from said reservoir to said chamber for fiashing to steam therein, said soleplate having an orifice in the bottom surface thereof for discharge of steam, said iron having a first passage for liow of steam from said chamber to said discharge orifice,

means providing a second passage between the upper portion of the interior of said reservoir and a region uml...

of said iirst passage where the pressure of the steam flowing therethrough is less than maximum pressure in the chamber and greater than the maximum pressure at the orifice, and

baie means in said first passage separating the downstream portion thereof into a region communicating with the discharge orifice and another region communicating with said `second passage.

2. A steam iron including a soleplate having a steam generating chamber,

means for heating the soleplate in the region of said chamber,

a closed reservoir for water above the soleplate,

means `for supplying water in droplet form from said reservoir to said chamber for dashing to steam therein, said soleplate having an orifice in the bottom surface thereof for discharge of steam, said iron having a passage for ow of steam from said chamber to said discharge orifice,

means defining a restriction in the iiow path of steam through said passage, and

means providing a pressure-equalizing passage between the upper portion of the interior of the reservoir and a region of said 4steam flow passage downstream of the restriction therein.

3. A steam iron including a soleplate having a steam generating chamber,

means for heating said soieplate in the region of said chamber,

a reservoir for water above said soleplate,

a shell cooperating with said soleplateto house said reservoir,

a handle member including a front post mounted on said shell,

a drip valve positioned beneath said handle front post and providing for gravity iiow of water from said reservoir to said chamber for flashing into steam` therein, t manually-operable means carried by said fron-t post for controlling said drip valve, said soleplate having a plurality of orices opening through the bottom surface thereof for discharge of steam to material being ironed, said iron having -a passage providing communication between said steam generating chamber and said discharge orices,

a tube beneath said front post and near said drip valve providing communication between the upper portion of the interior of said reservoir and a'region of said passage intermediate said chamber and said discharge orifices, and

means restricting said passage between said region thereof and said chamber.

References Cited in the iile of this patent UNITED STATES PATENTS Finlayson et al June 30, 1959 Swenson ..V July 11, 1961

Claims

1. A STEAM IRON INCLUDING A SOLEPLATE HAVING A STEAM GENERATING CHAMBER, MEANS FOR HEATING THE SOLEPLATE IN THE REGION OF SAID CHAMBER, A CLOSED RESERVOIR FOR WATER ABOVE THE SOLEPLATE, MEANS FOR SUPPLYING DROPS OF WATER FROM SAID RESERVOIR TO SAID CHAMBER FOR FLASHING TO STEAM THEREIN, SAID SOLEPLATE HAVING AN ORIFICE IN THE BOTTOM SURFACE THEREOF FOR DISCHARGE OF STEAM, SAID IRON HAVING A FIRST PASSAGE FOR FLOW OF STEAM FROM SAID CHAMBER TO SAID DISCHARGE ORIFICE, MEANS PROVIDING A SECOND PASSAGE BETWEEN THE UPPER PORTION OF THE INTERIOR OF SAID RESERVOIR AND A REGION OF SAID FIRST PASSAGE WHERE THE PRESSURE OF THE STEAM FLOWING THERETHROUGH IS LESS THAN MAXIMUM PRESSURE IN THE CHAMBER AND GREATER THAN THE MAXIMUM PRESSURE AT THE ORIFICE, AND BAFFLE MEANS IN SAID FIRST PASSAGE SEPARATING THE DOWNSTREAM PORTION THEREOF INTO A REGION COMMUNICATING WITH THE DISCHARGE ORIFICE AND ANOTHER REGION COMMUNICATING WITH SAID SECOND PASSAGE.