US2608773A - Steam iron having improved water reservoir and steam generator - Google Patents

Description

F. E. FIN LAYSON Sept. 2, 195 2 STEAM IRON HAVING IMPROVED WATER RESERVOIR AND STEAM GENERATOR Filed Jan. 18, 1951 m y 8 6% n O P tm m w b v mm .s m H S a Patented Sept. 2, 1952 STEAM IRON HAVING IMPROVED WATER J5 :RES ER YO IR AND STEAM-GENERATOR i "EfEin'layson, Ontario." Calif., assignor to v General Electric ;Q01 npany;. a corporation of;

New York 1.

epplicationJanuary m, 1951, S.eria1.No.206,55 5l I zoia (c1. ass- 77) This; invention relates to electrically heated steam,pressing.irons of thehancltype havingan instantaneous steam. generatonandis directed particularly .to. an improved: construction'of: the water supply; reservoir and, steamgenerating means. (Steam irons of the type to which this invention is. directed include an electrically heated sole plate provided. with/an instantaneous orflash steam generating cavity formed in the sole plate torreceive water at a relatively slow rate-from a water reservoir mounted within the iron. Obviously, such an iron 'requires a suitable cover plate extending'over the sole plate to confine and" direct the generated steam through discharge ports extendingthrough the sole plate to the pressing surface of the iron. Toinsure complete vaporization of the water particles; the cover plate preferably is ofa material having a high thermal conductivity so that it is heated to substantially the same temperature as the sole plate. v v

For convenience ofcperatiorrth'e water-reservoir is mounted within the body of the iron, that is, between the upper surface of the sole plate-and tlieinside'of the outer enclosing shell of the iron." However, with this constructionit is de-' -siifable to limit to a minimum the heat transfer from the sole plate or its cover plate to the reservoir. Otherwise water stored within the reservoir is unnecessarily evaporatedat the expense of heat drawn from the sole plate. Correspondingly. it has been found desirable to interconnect the reservoir with the cover plate of the steam generating chamber by a member having a low thermal conductivity. This member. or boiler cover. as hereinafter referred to, also serves as a mounting means for theapertured port controlling water flow betlween the reservoir and the steam generating cavity. With respect to normal ironing pos t on; t b il r o r pr f ab y extends upwardlyfin' order to space the reservoir from the cover plate;

Since the "cover platewhich' extends over the steam generating chamber andthe boiler cover interconnecting the cover plate with the reservoir are normally of different. materials, it has heretofore been custOmarytomanufacture these cornponentsl as separate parts, which upon assembly, are attached. togetheriin asteam-ti'ght fashion through the use of a suitable gasket and fastening means. With such a construction, I have found cover to the. cover plate.

in' massproduction to achieve an eifectiveseal be.- tween the boiler cover-and the cover plate. Fur.- thermore, assembly is relatively expensive clue: to therequirement for the gasket and a plurality of fastening screws to fasten securely the; boiler It is an object of the present invention toelin ignate the above-mentioned:difiiculties Whi1e;pro viding an efiectivev seal at alower production :cost. Another objectof-my invention isto provideia steam. iron construction. reducing, manufact1n'ingv and assembly costs. I

In accomplishment of-lfthe foregoingobjec; tives, a feature of; my inventionconsists in. 211- ploying acover. plate for the steam generating chamber of-materialhaving.- ahigh thermalicon; ductivity and having; integrally- -castgtherein. a boiler cover of relativelyilow thermal .conductivi ty extend-ingtoutw'aridlyfrom the cover plate. The boiler cover additionallyservesaas a means for supporting awater reservoir and. for mountmg a water discharge-port between the reservoir and the steam generating chamber. Q 1

The features of my invention which-I: believe to be novel are set forth with particularity. in the appended claims. -My"'inventi'oniitself; however-{both as to its organization .and methodcof operation, together with'further objects and'l'a'de vantages thereof, may best be under'stoodbyref erence to the following description taken in fconj-L nection with the accompanying drawing, in which Fig. 1 is a side elevation ofan iron embodying my invention, pgnrtia'lly'sectio nalized on the longi I tudi-nal center line of the iron; Fig. 2 is-a'bdttom plan view of the cover plate and boiler cover; 'ancl- Fig. 3 is a partial cross sectional view tal'ge'ri on the line 3-3 of-Fig. 2. a g

Referring to the drawing,-in Fighl 'I have shown my invention as embodied in a steamiron having a sole plate Landan enclosing bod-$ 01 shell 2, to' which may be attached' 'a suitableop that the gasket presents the very unsatisfactory.

parts.- Furthermore, it has been found-difficult crating handle 3. 'Thesole plate may be heated by a suitable element; preferably consisting of a helieally coiled resistor 4 completely enclosed within an outer sheath {and held in spacedre lation with respect to the sheath by a heat-trans";

mitting; electrically insulating substance as highly compressed granulated magnesiumox;

ide. The heating element may be controlled a suitable automatic thermostatic mechan (not shown) adjustable by means ofal tempera ture controlling knob 3a. Preferably; the sole;

plate is formedfrom lightweight'thermaliy con? ductive material, such as cast aluminum, with the tubular heating elementembedded) therein over the cover plate aperture 26.

To provide a means for interconnecting the steam generating chamber 1 with water reservoir 9, cover plate I! is centrally apertured at 26; similarly, water reservoir 9 is apertured as at 21. in substantial vertical alignment with the aperture through the cover plate and the steam generating cavity 7. 1 In accordance with the present invention; I provide a boiler cover 28 extending This construction is shown clearly in Fig. 3. Preferably boiler cover 28 is fabricated in an inverted cup-shape face through suitable apertures such as 8. extending through the sole plate to the pressing surface.

For convenience in operation it is obviously liner Il and'handle portion Ill to a point adjacent the outer end of the liner. The liner and fill tube may be secured in position with-respect to the handle by a suitable fastening means such as screw H3." The upper portion of both the fill tube and liner, as well as the handle, are apertured at M, with this aperture facing forwardly when the iron is in its normal ironing position. The iron is provided with a conventional heel rest formed by a protuberance l5 on the handle and a rear portion l6 of the body of the iron, so that the iron may be up-ended to 'a rest position. In such rest positionitmay be seen that aperture l4 faces upwardly permitting water to be poured into the-fill tube whereupon it"fiows into reservoir 9.

Such a construction has been disclosed and claimed in my copending application Serial No. 69,756, filed January 7, 1949, assigned to the General Electric Company, assignee of the in:- stant application, now Patent Number 2,587,608, patented March 4,1952. 5

To confine steam generated within cavity 1, Iemploy a cover plate I! overlying the upper surface of the sole plate and attached thereto by suitable fastening means such as screws l8. As shown more clearly inFig. 2, cover'plate [1 includes an outer depending flange is extending entirely around its outer edge for sealing engagementwith the upper surface of sole plate I. Additionally, and as shown in the bottom view of Fig. 2, the cover plate includes a plurality of depending ribs to define in cooperation with the sole plate a tortuous passage through which the steam must pass before being discharged through the apertures 8 in the sole plate. For example, a pair of ribs 20 and 2| may direct the steam rearwardly over the highly heated surface ofthe sole plate, and additional ribs 22 and 23 may be provided for defining forwardly extending passages. vWhile in Fig. 2 I have'shown only two sets of such ribs, obviously any number may be.

. trol member is bowed at 3,4 for frictional engag er,

from a material such as stainless steel having relatively low thermal conductivity. In addition, I have'found'it desirable to fabricate boiler cover 28 with a minimum cross-sectional thickness. commensurate with the required mechanical rigidity; As explained above, cover plate I! preferably has a high thermal conductivity so that its temperature closely approaches the temperature of the sole plate. This is an aid in achieving complete vaporization of water discharged into the. steam generating cavity before discharge through the pressing surface. By utilizing a low conductivity material for boiler cover 28, along with fabrication with a minimum cross sectional area, heat transfer to the reservoir from the sole plate may be greatly reduced. Secured to the outer or upper end of boiler cover 28 is a bushing 29 internally threaded as at 30. Bushing 29 may be secured and sealed in position with respect to the boiler cover .by brazing or welding. For attachment of the boiler cover to the cover plate, I provide an annular curled flange 3| which is adapted to be placed as an insert in a mold for the cover plate. Thus; when the cover plate casting is poured, the molten metal flows around both surfaces of the flange 3! on the boiler cover to anchor it in-position with a steam-tight seal. It maybe seen that by thismanner of interconnecting the boiler cover tothe cover plate, assembly is greatly facilitated, since separate fastening means for the boiler cover have been eliminated, and no gasket is required to provide a steam-tight seal. i j

Referring again to Fig. l, bushing 30 is m ternally threaded to receive an apertured port member 30a. The upper portion ofmember 30a is of greater diameter than its threaded portion, so that as it is threaded into bushing 30,- the walls surrounding the aperture in the reservoir are securely clamped between port member 300 and the upper surface of bushing 30. If desired, suitable gasket material may be employed to obtain a water and vapor-tight seal, although this is unnecessary with the depicted embodiment.

33 of the flow .control member is adapted to.

extend through the port in member 30a to pre-v vent flow of water to the steam generating-cavity. The upper intermediateportion of theflow conment withthe inside wall, of fill tube l2. The extreme upper portion of the flow control member. extends out through an opening in the rounded outer end of liner 1 l and includes a finger operating means 35 conveniently positioned for manual operation from handle 3.. With. this arrangement, the flow control member may be moved longitudinally of the fill tube to either permit or cut off water flow through port member 3| into the steam generating cavity. As

shown in Fig. 1, it is preferred to have aportion of the flow control member extend through the port in member 3| when in its flow cut-off position, so that scale or dirt particles which might accumulate in this flow passage may be cleaned or forced out by the flow control member. This particular construction of the means for controlling water flow from the reservoir to the steam generating cavity forms no part of the present invention, but is disclosed and claimed in the copending application Serial No. 69,774 of Alfred G. Swenson, filed January 7, 1949, and assigned to the General Electric Company, assignee of this application, now Patent Number 2,587,665, patented March 4, 1952.

From the foregoing disclosure it may be seen thatI have provided a steam ironconstruction having an improved relation of the components to facilitate steam generation while minimizing heat loss to the water storage chamber.- By the construction here presented with the boiler cover integrally cast as an insert with the cover plate extending over the steam generating means, I have improved both the operability and the life, while at the same time providing a construe tion of decreased manufacturing cost. A device in accordance with the foregoing disclosure may be fabricated without the use of gasket materials which tend to support corrosion and develop vapor leaks. Furthermore, no separate fastening means are required for securing the boiler cover to its associated cover plate.

While the present invention has been described by reference to a particular embodiment thereof, it is to be understood that numerous modifications may be made by those skilled in the art without actually departing from the invention. I, therefore, aim in the appended claims to cover all such equivalent variations as come within the true spirit and scope of the foregoing disclosure.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. In a steam pressing iron, an electrically heated sole plate comprising metal having high thermal conductivity and having a steam generating cavity therein, a cover plate of similar metal positioned on the sole plate over said cavity in thermal contact therewith to define a steam generating chamber, said cover plate having an opening in line with said cavity, a water reservoir positioned in the iron above and in spaced relation to said sole plate and cover plate, and walls including a boiler cover cast integral with said cover plate and covering the opening therein which connect the reservoir to said cover plate and define a passage for flow of water from the reservoir to said chamber, said boiler cover being formed of metal of thin cross section and relatively low thermal conductivity compared to the metal of said cover plate whereby it serves to minimize the transfer of heat from the cover plate to the reservoir.

2. In a steam pressing iron, an electrically heated sole plate comprising metal having high thermal conductivity and having a steam generating cavity therein, a cover plate of similar metal positioned on the sole plate over said cavity in thermal contact therewith to define a steam generating chamber, said cover plate having an opening in line with said cavity, a water reservoir positioned in the iron above and in spaced relation to said sole plate and cover plate, an inverted cup-shaped boiler cover positioned over said cover plate opening and having its rim cast integral with said cover plate, said boiler cover being formed from thin metal of low thermal conductivity compared to the metal of said cover plate, and means connecting the boiler cover to the reservoir which defines a passage for flow of water from the reservoir to said chamber, said boiler cover serving to minimize the transfer of heat from the cover plate to the reservoir.

FRANK E. FINLAYSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS

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