US3111780A - Steam iron - Google Patents

Description

A. D. SMITH Nov. 26, 1963 STEAM IRON 2 Sheets-Sheet 1 Filed MaIOh 20, 1962 A. D, SMITH Nov. 26, 1963 STEAM IRON 2 Sheecs-Shee'cl 2 Filed March 20, 1962 NE 2N2] FOU I On.

United States Patent O 3,111,730 STEAM HRQN Alan D. Smith, ltlansiield, Ghia, assigner to Westinglaoase Electric tCorporation, East Pittsburgh, Pa., a corporation of Pennsylvania Y Filed li/iar. Zi?, 1962, Ser. No. Nihil?) 3 Claims. (Cl. 35i- 77) This invention relates to an electrically heated latiron, especially a steam iron also useful as a dry iron.

Electrically heated ilatirons normally have a resistance heating element in the `soleplate and have a thermostat in conjunction therewith to maintain the soleplate at the desired temperature. The thermostat is manually adjustable to permit selection of appropriate ironing temperature for fabrics of various compositions. While the thermostat necessarily is located at :or near the soleplate, the adjusting means preferably is lat a cooler location, where it can be manipulated readily by the user of the iron. A temperature scale calibrated according to fabric composition is a customary accompanying feature.

Steam irons have, `in addition to such provisions for temperature control, certain aparatus features necessitated by the 'adaptation for steam ironing. These may include one or more manual controls `for limiting the admission of water into a storage reservoir, and the emission of water therefrom, as into ya flash or vaporization charnvber, for example. Of course, these controls also must be readily lavailable to, but not unnecessarily in the way of, the user of the iron. As proper operation and wholehearted acceptance of the iron by the consumer depend upon simplicity and reliability of the respective control features, as well as of the rest of the mechanism, it is desirable to minimize the manipulations required thereby on the part of the user of the iron.

A primary object of the present invention is simplification of the manipulative control features of a steam iron.

An object is provision of a steam iron with unified control of temperature and of water content.

Another object is preset correlation between the rate of n steam generation and the ironing temperature of a steam iron of the ilash type.

A further object is compact construction of temperature-regulating means for an electric iron.

Other objects of this invention, together with means and methods of attaining the various objects, will be apparent from the following description, and the accompanying diagrams, of a preferred embodiment of the invention.

FIG. 1 is a View in side elevation, largely in section, of

an electric iron in accordance with the present invention;

FlG. 2 is a perspective view, partly in section, of a portion of the article of FIG. 1, including mechanical linkages responsive to various settings of the control knob visible at the upper left;

FIG. 3 is an enlarged plan view of the Iupper anterior portion of the article of FIG. 1, including indicia for various settings of the superimposed control knob; and

FIG. 4 is a schematic representation of the positions of certain cam elements of FIGS. 1 and 2 at various settings of the control knob.

In generel, the objects of the present invention are accomplished, in -a steam iron having an electrical heating element for the soleplate thereof and a thermostat for controlling the soleplate temperature and havin-g a water reservoir and means for controlling changes in the amount of water in vthe reservoir, by movable cam means having thereon, in iixed relation lto one another, respective cam surfaces for temperature control and water control.

The invention contemplates particularly, in temperature-control means for such an iron, a disc-shaped cam member pivoted on a vertical Iaxis, with reference to normal ironing orientation, :a yoke generally surrounding the cam member yand pivo-ted lon -a horizontal axis, a cam surface for temperature control on the upper face of the cam member, a cam follower on the yoke and in juxtaposition to the ca fn surface, spring means biasing the cam follower into contact with the cam surface, and a connecting rod substantially diametrically opposed to the location of the cam follower `and depending from the yoke.

FIG. l shows steam iron lll, in side elevation, largely in medial section (from toe to heel). Part of handle ll, water reservoir l2 and soleplate 16, together with certain components located on or near the medial plane, appear in solid, while the rest of these parts and moet of .the other illustrated parts are sectioned vertically (with reference to the normal 4ironing orientation shown in this view). U-shaped bracket i4, which is secured to the soleplate by cap screws 15 (one visible), supports the reservoir and surrounding -shell ld, which substantially entirely covers the soleplate. Handle ll is secured Vto the top-of the shell by screws 1d (one visible) threaded upward into base portion i9 of the handle through suitable apertures in the shell. The bla-se portion joins the visible front and rear handle portions, which also are joined by grip portion ft) spaced above and generally para-lieling the base. Bolt 2l surrounded by sleeve bushing 22 extends ythrough eye 23 of the reservoir and secures the shell to the U-shaped lower and upper washers 25 and 26 respectively, both the bracket by means of a nut 2li at the upper end and lower land upper washers Z5 and 26 respectively, both the bracket and the shell having suitable apertures therein. A cover plate 2.7 for the nut 24 on bolt 21 snaps into opening 28 in handle base i9.

The soleplate has an electrical heating element 31, preferably of the sheathed type, embedded in it. The electrical leads for the heating element originate at cord 35, which extends from an external source of electrical potential (not shown) through grommet 36 litted in the rear portion of handle lll and into hollow 41 therein. This rear hollow in the handle opens downwardly into opening d2 in shell 16. The shell slopes downward and out ward -at the rear to overhang the heel of the soleplate, and the overhang is closed by access plate 43 attached by screws 44 to oiiset bracket 45. The offset bracket is secured by screws 47 to a pair of bosses 46 spaced transversely from one another on the upper face of the soleplate, as appears more clearly in perspective in FIG. 2 (only one boss 46 being visible, however).

Thermostatic switch Si lcomprises rigid arm 52 and shorter bimetal arm 53 underneath it. The arms are riveted to one end of respective flexible strips 54 and 55, which are faxed at their opposite ends to upper and lower terminal strips 56 and 57. Insulating block 58 on the portion of offset bracket 45 overlying `and bridging bosses 47 of the soleplate spaces the upper terminal strip from the offset bracket, while the lower strip is spaced therefrom by insulating strip 59 aixed to the underside of the support bracket between the bosses. The upper terminal strip has electrical lead 62 secured to its upturned end by screw 63. This lead joins one of the pair of leads from cord 35 (at insert 65 retained in the handle) in hollow 4l of the handle after passing through opening 42 in the intervening shell. The other lead from the cord terminates at a like insert (Ihidden from view) at which it is connected to a hidden end of the heating element by a suitable interconnecting lead (not shown). Electrical lead 67, which is secured to the upturned end of the lower terminal strip by screw 66, connects to the other end of u the `heating element, an exposed portion of sheath 32 thereof appearing about `a fourth of the way to the toe or forward end of the iron. Rigid arm 52 of the thermostat carries electrical contact 63 opposite electrical contact 59 on birnetal arm 53.

The forward end of the rigid arm has riveted to it insulating strip 7l, which has opening 7?. in it. Split lower end 73 of connecting rod 7d is clinched about the marginal portion provided by the opening in the insulating strip so as to provide a pivotal interconnection therewith. The connecting rod, :which is adapted to move lu ard and d wnward as indicated by the double-headed arrow nearby, extends upward through eye '75 in reservoir l2 iuto hollow in the forward portion of handle ll, where it threads into the lower end of elongated hex nut 76, the other end of which is secured to the bight of U-mernber '77 by screw 78 through a suitable aperture therein. The ends of the U-member are pinned pivotally to the ends of yoke Sti, which extends forwardly therefrom. The yoke is supported on a pair of horizontal pivot pins 32 (visible in FlG. 2) through upturned ears on support plate The support lplate rests at its opposite side edges on front and rear steps 3o and 37 (one of each being indicated in FlG. l) in the interior wall of the surrounding handle and is secured thereto by screws (one visible).

Support plate supports, in addition to yoke Stil, generally disc-shaped member @L which is secured pivotally on the upper surface of the support plate by downwardly extending headed rivet 552, which has a retaining washer 93 at its lower end. The disc-shaped member has upper cam surface 9S and lower cam surface 96 on its respective faces. Tang 97, which extends upwardly and rearwardly from the biht of yoke Sil, has threaded through it (in a suitable aperture in its horizontal portion) headless screw 99, which is juxtaposed the upper cam surface as a cam follower therefor. Pair of torsion springs 162 surrounding yoke pivot pins SZ, and bearing against the upper rear surface of the support plate and the upper edge of the bight of the yoke, bias the bight of the yoke downward to bring the headless screw into Contact with the upper cam surface. lt will be apparent from the previous description of linkage between the yoke and rigid arm 52. of thermostatic switch l that temperature regulation is accomplished by means of the upper cam surface and its follower through the medium of such linkage and the yoke itself.

Bise-shaped member gli has extending from the portion ot it located at the left (i.e., front) in FGS. 1 and 2 oset support strip lti for control knob ldd. This support strip extends radially from its junction with the discshaped member, then upwardly, and finally further outwardly parallel to the radial direction and through slit Itt (v. FlG. l) between the top edge of wall lilo, which surrounds front hollow Sl in the handle, and cover l7 for the hollow. The cover fits snugly against the inside edge of the wall at the top of the hollow, and the slit extends throughout an arc oi slightly more than one-half of a circle, at the front and the opposite sides. The control knob has pointer ldd extending radially inward toward the vertical axis of the disc-shaped member and over the outer edge of indicia plate X09 affixed to the top surface of the cover. The indicia plate, with the control knob superimposed thereon, appears in plan in FIG. 3, which is discussed hereinafter.

Passageway lll for water is provided in the front of wall lilo of the handle. This passageway docs not communicate with hollow but is adapted to communicate (down. ardly) with reservoir l2 when the control knob is moved to the extreme counter-clockwise position, as hereinafter more fully explained. The reservoir terminates in collar lll immediately beneath the inner downwardly oriented terminus ot passageway lill and is sealed to surrounding portion il?) of the handle by intervening gasket iid. Shown seated against this portion of the ,trineo handle and thereby closing the passageway oil from the reservoir is sealing disc i215, which is somewhat smaller in diameter than the gasket; The sealing disc has an axial bore therein through which passes valve stem ltZl. Clamp lZZ on the valve stem about midway between he base and the collar of the reservoir supports Washer ai/Z3, while compression spring llZl surrounds the valve stem between that washer and washer 125, which lies against the underside of the sealing disc. The lower end or" the valve stem is rounded to conform to valve seat and terminates in pilot probe 127 shown in place in throat l2@ or the valve. The valve seat and throat are formed in valve insert R29, which forms the outlet for water from the reservoir. The upper end of the valve stem lits snugly but slidably in a bore 131 in that portion of the handle wall separating passageway lll and hollow 8l. Afhxed to the portion of the valve stern in the passageway is clamp B2. Loosely surrounding the valve stem below this clamp is collar 133 of figure-S clamp 34.

Figureclanp d Aalso encircles push rod 135 (which parallels valve stern 21) and is atiixed thereto by set screw 23o. T he push rod terminates at its lower end near the upper surface of sealing disc land extends up- .'ard from clamp 134 slidably and snugly into and through bore l paralleling bore E31 in the handle wall. Compression spring L3?) is retained about the push rod between the upper surface of the adjacent wall (about bore i3?) and clamp "r3-9, which is .affixed to the rod. The upper end of the push rod is juxtaposed to (lower) cam surface 96 on t e under face of disc-shaped member 91 and is biased into contact therewith as a camfollower by the con session spring 13d. It lwill be apparent that the push rod and parallel valve stem, together with their vassociated parts, are instrumental in controlling the admission of water into and emission of water from reservoir (as is described more fully hereinafter). To the extent that the structure thereof constitutes subject matter of a patent application of Samuel R. Bricker, Serial No. 179,357, tiled March 13, 1962, it is excluded from the present invention, the subject matter of the present applicatlon.

Valve insert 1219, hanged at its upper end just inside reservoir .T Z, extends downwardly (v. FIG. l) to and through cover plate 'Md for soleplate lo and into vaporization chamber Surrounding the intervening peripheral portion of the insert is packing M3, which is retained in place by packing gland 144 crimped to the upper `face of the cover plate, which in turn is secured to the soleplate by screws. The underside of the cover plate is provided with channels M5, which conjoin channels Mo in the upper surface of the soleplate and interconnect tne vaporization chamber with steam discharge ports M7 (only one being visible) through the base of the soleplate. -Pressure-equalizing tube 14S extends from one of channels 145 through the packing beside the valve seat and through grommet lid-9 located in a suitable aperture in the bottom of the reservoir and terminates inside collar M2 of the reservoir.

The operation of this iron is readily understood, especially by reference to FlG. 3, previously mentioned, which shows (in plan) indicia plate MP9 on cover lt'i7. Part of wall lilo of the handle is visible out from under the cover and the indicia plate, `and control knob 104 is located at the left (front edge) fwith its pointer Hi8 extending back over the plate. 'A printed scale on the plate is divided into tour panels, each with indicia or legends, as follows (reading clockwise):

oFF Wirtin-WEAR 151, FrLL; 152, Lo SYN Hr; 153, Wooll COT LIN and STEAM 154,1.0 HI

meaning of the respective legends is inmediately apparent, and will be most readily understood in their relation to the associated mechanism by reference to `the next view.

FIG. 4 is a schematic representation of the upper and lower cam surfaces and the positions of their respective cam followers (headless screw 99 and push rod 135) for control of both temperature and water throughout the range of possible settings of the control knob (not shown in this view). The cam surfaces are developed, i.e., laid out in the plane of the paper, representing corresponding positions of the cam followers (indicated adjacent thereto, aligned with one another). Of course, control -knob 104 is movable manually throughout the entire width of all four panels 151, 152, 153, and 154, a total of approximately two hundred ten degrees. The representation of the respective cam followers, shown in solid in alignment with the Word WOOL in the left portion of third panel 153, ras compared with phantom (broken line) representations thereof elsewhere within the range presented by the four panels, corresponds to the setting of the control knob in the preceding views.

IWhen control knob 104 is positioned at the furthest counterclockwise location (at the extreme left in FIG. 4) both cam followers are at their lowest positions. The extreme low position of the upper cam follower corresponds to such la high position of rigid arm 52 of the thermostatic switch that contacts 63 and 69 are not contiguous at any Ordin-ary ambient temperature; this open circuit to the heating element leaves it unenergized or OFF so that the iron does not become heated. The extreme low position of the lower cam follower corresponds to a position in which push rod 135 depresses sealing disc 115 by contact therewith l(as indicated by the arrow in FIGS. l and 2,), permitting water to be introduced into reservoir 12 through passageway l111. The iron usually is tipped up on its heel to orient the passageway for easier introduction of Vwater at this =FILL position. It -Will be apparent that when the control knob is centered over panel 151, rather than at the extreme left thereof, the lower cam follower rises (biased by compression spring 13S) along the lower cam surface to a higher level, at which the sealing disc is biased closed by compression spring 124. At both these positions of the lower cam follower, valve stem 121 is biased downward against valve seat 1216 by ycompression spring 124, so no water can be emitted from the reservoir into vaporization chamber 142.

The lower cam follower remains tat this neutral level at 'all positions of knob 1614 throughout an intermediate range provided by the next two panels, 152 `and 153, as the lower cam sunface is horizontal through both of them, while the upper cam follower follows a rising cam surface, corresponding to increasing dry ironing temperatures. IIt is app-arent that higher and Ihigher positions of the upper cam follower correspond to lower and lower positions of rigid -arm 52 of the thermostatic switch, closing the contacts so that bimetal arm 53 must bend downward farther and farther at its fnee or Contact end (under the influence of increasing soleplate temperature) to open the energizing circuit to the heating element. The action of the thermostatic switch itself is wholly conventional.

As knob .164 reaches the `fourth y(or extreme clockwise) panel 154, however, the upper cam follower declines to a position almost, if not quite, as low as its position at the beginning of the dry ironing range at the left side of panel 152 (WASH-WEAR, etc.) and then rises again on :a steeper incline to terminate at a level almost as high as the maximum reached at the right side of panel 153 (WOOL COT LIN). As indicated by the legend thereon, this last panel 154 covers the range of settings of the control knob for STEAM ironing. The lower cam follower rises gradually at the left side of this panel to a higher level, corresponding to withdrawal of the lower end of valve stem 121 away from valve seat 126. The valve opens in this manner as the bias of compression spring 124 on the valve stem is overcome by the bias of stronger compression Spring 138, which moves push rod upward as permitted by the lower cam surface and thereby lifts the valve stem by contact of ligure-8 clamp 134 Iwith clamp 132 on the valve stem. When the valve is open, water present in the reservoir may pass (usually drop by drop) into vaporization chamber 142, where it is flashed to steam, which passes through conjoined channels and 145 and out through discharge ports 147 in the base of the soleplate.

raduation of the opening of the valve over the lower portion of the STEAM temperature range prevents spitting of unvaporized water through the discharge ports.

All through the dry ironing range of water content of the reservoir is fixed, no water being allowed to leave by way of the drip valve, to be converted to steam, nor allowed to splash out .of the reservoir by way of the inlet passageway. A convenient setting is provided, available only when the iron is turned olf, for opening the inlet passageway to permit addition of water to the reservoir, and a suitable range of operating temperatures is provided at settings for STEAM ironing. The compact design and disposition of the linkages for the various controls in the hollow interior of the front portion of the handle is especially advantageous, not only facilitating location of the control knob at the most desirable operating location but also rendering the mechanism readily available from the exterior in the event that some maintenance should be required. Manufacturing economy is an additional advantage of this simplified unitary control arrangement.

The illustrated and described embodiment of this invention is exemplary, and modifications may be made therein without involving a departure from the invention. Parts may be combined or divided, changed in size, shape, or orientation, 'and even possibly omitted while maintaining the advantages and benefits of this invention, some of which have been mentioned above and others of which will be come apparent to and be enjoyed by those undertaking to practice the invention as claimed.

What is claimed is:

l. ln temperature-control means for an electrically heated flatiron having a thermostatic switch with an adjusting arm and a bimetal arm adapted to bend away from the adjusting arm at ironing temperatures, the respective arms having electrical contacts opposing one another thereon and adapted to close when the temperature of the iron is less than required by the position of the adjusting arm, the thermostatic switch being located in the rear half of the iron, and the adjusting arm extending forwardly thereform, tie iron also having an attached handle extending Afore and aft, the combination of a manually movable knob located near the foremost and topmost part of the handle,

a cam member pivoted on a substantially vertical axis, with reference to normal ironing orientation, in the interior of the handle, the knob being adapted, upon movement thereof, to pivot the cam member,

a yoke generally surrounding and spaced from the cam member and disposed generally horizontally,

pivot means supporting the yoke for movement about a substantially horizontal axis intenmediate its ends with its closed end `forwardly and its open end rearwardly of said axis,

a cam surface -on the cam member,

a cam follower on the yoke adjacent the closed end thereof and juxtaposed to the cam surface, and

mechanical linkage interconnecting the open end of a the yoke and the forward end of the adjusting arm of the thermostatic switch,

2. A steam iron comprising a soleplate having a Varporization chamber and discharge ports therefrom through the base of the soleplate, an electrical heating element for the soleplate, a thermostat for controlling the temperature to which the soleplate is heated, a water reservoir, means for controlling the admission of 'water into the reservoir and the emission of water from the reservoir into the vaporization chamber, movable cam means having a iirst cam surface lfor the thermostat and a second cam surface for the water-control means, a rst cam follower juxtaposed to the iirst cam surface, rnechanical linkage operatively connecting the first cam tolloweito the thermostat, and a second cam follower juxtaposed to the second cam sur-face operatively connected to the water-control means, said respective cam surfaces having two extreme position intervals andan intermedia-te range of positions, and wherein, at one eatreme, the first follower is cammed to disconnect the electrical heating element, and the second cam follower is cammed to open the reservoir to the addition of water, in the intermediate range, the first follow-er cammod through a range of temperatures suitable for ry ironing, and the second follower is cammed to seal oil the water reservoir, and at tne other extreme, the rst follower is cammed within a narrower temperature range suitable for steam ironing, and the second oam follower is cammed to open lthe reservoir to the gradual loss of water for conversion into steam.

3. A steam iron comprising a soleplate having a vaporization chamber and discharge ports therefrom through the oase of the soleplate, and electrical heating element for the soleplate, a thermostat 'for controlling the temperature to lwhich the soleplate is heated, a water reservoir, means for controlling the admission of water into the reservoir and the emission of water from the reservoir into the vaporization chamber, movable cam means haivng a tiret cam surface for the thermostat and a second cam surface for `the Water-control means, a first cam follower juxtaposed to the lirst cam snrtace, mechanical linkage operatively connecting the first cam follower to the thermostat, and a second carn follower juxtaposed to the second cam surface and operatively connected to the water-control means, the linkage connecting the irst earn `follower to the thermostat comprisinfy a yoke supported pivotally at its opposite sides, with the movable earn means located spaced within the yoke, and with the first cam follower supported on the yoke intermediate the supporting pivots, and a connecting rod pivotally attached at one end to the opposite intermediate portion of the yoke, and at the opposite end to the thermos-tat.

References Cited in the tile of this patent UNITED STATES PATENTS ...n hat.

Claims (1)

1. IN TEMPERATURE-CONTROL MEANS FOR AN ELECTRICALLY HEATED FLATIRON HAVING A THERMOSTATIC SWITCH WITH AN ADJUSTING ARM AND A BIMETAL ARM ADAPTED TO BEND AWAY FROM THE ADJUSTING ARM AT IRONING TEMPERATURES, THE RESPECTIVE ARMS HAVING ELECTRICAL CONTACTS OPPOSING ONE ANOTHER THEREON AND ADAPTED TO CLOSE WHEN THE TEMPERATURE OF THE IRON IS LESS THAN REQUIRED BY THE POSITION OF THE ADJUSTING ARM, THE THERMOSTATIC SWITCH BEING LOCATED IN THE REAR HALF OF THE IRON, AND ADJUSTING ARM EXTENDING FORWARDLY THEREFROM, THE IRON ALSO HAVING AN ATTACHED HANDLE EXTENDING FORE AND AFT, THE COMBINATION OF A MANUALLY MOVABLE KNOB LOCATED NEAR THE FOREMOST AND TOPMOST PART OF THE HANDLE,

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