US2783561A - Steam iron - Google Patents

Description

March 5, 1957 R. I. HUFFMAN 2,783,561

STEAM IRON Filed June 21, 1954 2 Sheets-Sheet '1 INVENTOR.

Rune/ll. Huffman March 5, 1957 R. l. HUFFMAN STEAM IRON 2 Sheets-Sheet 2 Filed June 21, 1954 I. 3 a 4 wh X m NN wk ow S Q n. W R. Q Z x a mm .r. WV 3 MN NM Q w 3 mm w m 8 L 1 Nu. 5% w NM. G Y 5 Q. m B J/ 1 R w ww H I R U I i 46 Q\ g \w Na q .W D W V v r Q Q 7 v X m r l 5 KW United States Fatent O F STEAM IRON Russell I. Hutfman, Dover, Ohio, assignor to Knapp- Monarch Company, St. Louis, Mo., a corporation of Delaware Application June 21, 1954, Serial No. 438,039

Claims. (Cl. 38-77) This invention relates to a steam iron and particularly one which is of the flash or drip" type.

One object of the invention is to provide a steam iron having improved features whereby a water tank thereof is so mounted with respect to the sole plate of the iron that the water in the tank is kept from boiling, thereby eliminating the necessity of emptying the tank during a normal ironing operation and refilling with cold water, as water in a tank directly mounted on a sole plate boils. Boiling is undesirable in a flash type steam iron and does not occur with my arrangement.

Another object is to provide a steam iron in which the operator is able to switch from dry ironing to steam ironing, or vice versa, with a simple valve control.

Another object is to provide a construction which insulates the handle from the hot sole plate by interposition of an element forming an air space between the water tank and the sole plate, the handle being mounted on the water tank.

Still another object is to provide an arrangement which permits the tank to be smaller than usual and in which a normal capacity of 8 ounces of water provides a steam iron that is no larger than a conventional nonstearning iron.

A further object is to provide an exposed water tank or one located on the outside instead of under cover, thus permitting the use of a much smaller tank than usual and eliminating the necessity of providing space in the tank for the expansion of water usually necessary in connection with a flash or drip type steam iron.

Still a further object is to provide an arrangement which eliminates spitting or pulsations during the generation of the steam by utilizing a construction wherein a post is located directly below the water valve and water is dropped thereon one drop at a time so as to contact the upper end of the post and form a film thereon as it gravitates therealong before reaching the hot sole plate where it is converted into steam, the sole plate being heated by conduction from a heating element embedded therein.

Still a further object is to provide an arrangement which permits quiet conversion of water into steam even though the hot metal surfaces with which the water contacts are limed, and, at the same time, an arrangement which eliminates back pressure upon formation of the steam and permits the steam to be readily dissipated through the steam discharge openings of the sole plate.

With these and other objects in view, my invention consists in the construction, arrangement and combination of the various parts of my steam iron, whereby the objects above contemplated are attained, as hereinafter more fully set forth, pointed out in my claims and illustrated in detail on the accompanying drawings, wherein:

Fig. l is a side elevation of a steam iron embodying my present invention.

Fig. 2 is a plan view, thereof, substantially full scale, this view being enlarged relative to Fig. 1 and portions 2,783,561 Patented Mar. 5,

of the upper structure being broken away to show internal details.

Fig. 3 is vertical sectional view through the iron as taken on the line 3-3 of Fig. 2.

Fig. 4 is a transverse vertical sectional view on the line 44 of Fig. 3.

Fig. 5 is an enlarged vertical sectional view similar to. a portion of Fig. 3 showing the valve open as distinguished from being closed in Fig. 3; and

Fig. 6 is a sectional view similar to a portion of the upper left corner of Fig. 3 showing a control knob in position for opening the valve to the position shown in Fig. 5.

On the accompanying drawings I have used the reference numerals 10, 12, 14 and 16 to indicate in generate sole plate, a sole plate cover, a water tank and a handle. The sole plate 10 may be a die casting having a sheathed heating element HE embedded therein, the sheath being shown at 18, the resistance coil at 22 and insulating material at 20 filling the coil 22 and spanning the space between the outside of the coil and the sheath 18. The resistance wire 22 may be connected by suitable wires 24 (see Fig. 3) to a supply cord 26 and to a thermostat shown generally at 28. At 25 a tube is shown through the water tank 14 for the wires 24. The thermostat 28 includes a bimetal element 30 responsive to the temperature of the sole plate 10 and the thermostat may be adjusted by a rod 32 terminating in a control knob 34, the rod extending through a tube 36 of the water tank 14.

The sole plate 10 is provided with certain steam cavities which will later bedescribed and these are on closed by a cover plate shown generally at 38 which has a depending flange 40 around its outline, which flange is tapered to fit into a tapered groove 42. The cover plate 38 also has a tapered depending boss 39 in semicircular flange 41 and is retained in position by a pair of screws 44. Once the contacting tapered surfaces are limed"'up" from steaming operations they become sealed relative to each other. a

The cover plate 38 has a boss 46 extending upwardly therefrom adjacent the forward end of the iron. Both the sole plate cover 12'and the bottom wall of the tank 14 are perforated at the boss 46 to receive a valve seat fitting 52 which is threaded into the boss. The rear end of the sole plate cover 12 is secured in position by a pair of screws 47, the cover plate having a depending flangeheaded studs 48 are engaged with keyhole slots 50 of j the top wall of the cover plate 12 (see lower right corner of Fig. 2) before the fitting 52 is inserted, whereupon the sole plate, sole plate cover and water tank are readily held in assembled relation to each other. I

A valve rod 54 coacts with the fitting 52', being slidable therein and provided with a reduced extension 56" at its lower end as shown in Fig. 5. This extension is oppo site a post 58 which extends upwardly from the sole plate 10 for a purpose which will hereinafter appear.

The lower end of the rod 54 just above the extension 56 is adapted to normally seat on a seat 69 of the fitting 52- under the action of a spring 61. The rod 54 extends upwardly through a neck 64 of the water tank 14 which has a closure plug 66 in its upper end for guiding the-rod; 54. The neck 64 islocated in a bore 68 of the front; post of the handle 16 and a fillter tube70 extends,- in;=; wardly from the front end of the handle andterminates= within the neck 64. The filler tube 70 thus holds the front end of the handle 16 in position with respect to the water tank I4 while the rear end thereof is held in position by-a screw 71'.

A shoulder 72 is provided in the front portion of the handle 16 and above this shoulder is a valve operating element 74. This element is in the form of a block pivoted at 76 to the upper end of the valve rod 54' and has a stop pin 78 therethrouglr for the valve in its closed position as shown in Fig. 3. A flat cam face 80 on the valve operating element 74 is adapted at times to coact with the shoulder 72 as shown in Fig. 6 when the thumb engageable portion 82 thereof is rocked forwardly from the position of Fig. 3- to the positionv of Fig. 6. This operation raises the valve rod 54 from its seated position of Fig. 3 (as shown in Fig. to permit the desiredflow of water for steam generating purposes, as will hereinatter appear.

Surrounding the post 58 is a steam generating cavity 84, the bottom of which is part of the sole plate 10, and the heating element HE passes closely adjacent and around the front portion of this, as indicated by dotted lines in Fig. l; Steam generated in the cavity 84 flows around a bafiie 85 and into a cavity 86, and then into shallower cavities 88 bounded by walls 89 and 91 having gaps 90' and 92 therein leading to deeper cavities 94 and 96. Along each side in somewhat shallower cavities are openings 98 (four ateach side) and openings 1% (three adjacent the point of the sole plate) for discharging steam from the sole plate to the ironing surface thereof. Thus, a tortuous path is provided for the steam from the steam generating cavity 84 to the steam discharge openlugs 98 and 100, along which path the steam becomes superheated.

I have found that if water is dropped on a hot metal plate which is completely chemically clean the water will remain in a confined area and be converted to steam. However, if the plate is not completely chemically clean, the water will separate into drops that bounce around and there will be spitting rather than uniform steaming. I have further found that providing the post 58 eliminates this spitting even when the cavity 84 is not chemically clean such as when it has become limed from steaming operations). As a drop of Water is formed, as at 102 in Fig. 5, it comes into contact with the upper end of the post 58 which leads the water directly to the sole plate in the form of a film 104. that gravitates along the pin and when it reaches the hot plate 10 it is converted quietly into steam indicated by the stippling 106.in, Fig, 5. This eliminates back pressure as the steam is gradually instead of suddently formed, as. when pulsations. occur; Also with my arrangement it is unnecessary to use distilled water in the iron because liming is not objectionable. Therefore, ordinary tap Water can be used.

I consider the control of the water in the manner above described (the flow being relatively slow so that only a. drop at a time issues from the tank) as being an important feature of my invention.

Another important feature is the arrangement of the water. tank so that it is not in contact with the sole plate, and, therefore, the water in the tank does not boil, which requires emptying of the tank and refilling with cold water if ironing operations are to be continued. With my arrangement as little as 8 ounces of water is sufiicient for normal size ironings.

post imbedded in said sole plate, extending upwardly therefrom and terminating spaced from said orifice but sufficiently close thereto that drops of water from said orifice will bridge the space between it and said post.

2. In a steam iron of the character disclosed, a metal sole plate, a heating element embedded therein, said sole plate having steam cavities therein and having steam discharge openings leading from said cavities to the bottom surface of said sole plate, a cover for said cavities, said cavities including a water receiving cavity having a substantially flat bottom, a sole plate cover for said sole plate, a water tank surmounting said sole plate cover, said water tank having a discharge orifice spaced above said bottom of said water receiving cavity, and a metallic post integrally connected with said sole plate, extending upwardly therefrom toward said orifice and having a flat upper end terminating spaced from but closely thereadjacent for conducting, water drops from said water tank to said water receiving cavity.

3. In a steam iron of the character disclosed, a sole plate, a heating element embedded therein, said sole plate having steam cavities therein and having steam discharge openings leading from said cavities to the bottom surface of said sole plate, a cover for said cavities, said cavities including a water receiving cavity, a water tank mounted above said sole plate, and means for admitting water from said tank to said water receiving cavity, said means including a control valve and a post anchored in said sole plate, extending upwardly therefrom within said water receiving cavity and having its upper end spaced from said water admitting means and positioned to contact a drop of water issuing from said water admitting means before such drop drops therefrom.

4. In a steam iron, a sole plate, a heating element there for, said sole plate having steam superheating cavities therein and having steam discharge openings leading from said cavities to the bottom surface of said sole plate, a water receiving, steam generating cavity adjacent the front end of said sole plate, a sole plate cover for said sole plate, a water tank surrnounting said sole plate cover, means for admitting water from said tank to said water receiving, steam generating cavity, and an element in said last cavity and rigidly connected with said sole plate but spaced from said means to contact drops of water issuing from said means and conduct them as a film of water to said sole plate.

5. In a steam iron of the character disclosed, a metal sole plate, a heating element therefor, said sole plate having steam cavities therein and having steam discharge openings leading from said cavities to the bottom surface of said sole plate, a cover for said cavities, one of said cavities constituting a water receiving cavity adjacent the front end of said steam iron, a sole plate cover having a top wall spaced from said sole plate to provide an air space thereabove, a water tank surmonnting said solo plate cover, a metallic post imbedded in said sole plate and extending upwardly from the bottom of said water receiving cavity, and means for delivering water a drop at a time from said water tank to just above the upper end of said post whereby it will bridge said means and said post and form a film on the post, will gravitate therealong and will be progressively heated thereby before reaching the heated bottom wall of said water receiving cavity.

References Cited in the file of this patent UNITED STATES PATENTS Vance Feb. 9, I954

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