US1099988A - Electric flat-iron. - Google Patents

Description

BEST AVAILABLE COP.

C. P. MADSEN.

ELECTRIC FLAT IRON.

APPLICATION FILED SEPT. ze, 1912.

` 1,099,988. Patented June16,1914.

COLUMNA PLANOGRAPH CO., WASHINGTON. D. C.

BEST AVAILABLE coal UNITED STATES ITENT OFFICE.

CHARLES I?. IVIADSEN, OF CHICAGO, ILLINOIS, ASSIG-NOR TO THE MICHIGAN STOVE COMPANY, '.A. CORPORATION OF MICHIGAN.

ELECTRIC FLAT-IRON.

Specicatioxi of Letters Patent. Patented J 1,1116 16, 1914:.

Application iiled September 26, 1912. Serial No. 722,416.

Acan be used than where the element is made up of a single winding, or where windings are connected in series. ,It is alsoknown that the heat emissivity ,rateV of resistance materialV is increased by pressure. I 'have Yalso discovered thatrthe working capacity `or ability to dissipateor'to generate and to convert electric energy into heat energyA at. high temperatures is much greater inv smaller wires than'in large4 ones. In constructingheating elements for 'use in electric heating `devices of the pressure plate system of construction, I take advantage of thesel facts by using relatively small conductors arranged with two or more coilsV in multiple and thereby gain the advantage of requiring not only a smaller mass of -wire to do a given quantity vofwork, but also,

find it easier and more convenient to arrange forA the The main objects Aof .this invention are therefore to provide an improved orm and construction of heating elements adapted for use in electric heating devices of various designs; to provide ari-improved Winding of resistance material vwhereby resist-i ance material of smaller size and capacity may be used than wouldotherwise be possible; to provide improved meansfor making electrical. connections between the resistv ance windings and the electrical conductors; to provide improved means for connecting the windings of the heating elementwhereby they are securely held in their relative position and whereby they are adapted to -be conveniently handled; to providel an proved form of insulation for the heating element;- andto provide aniinproved element of this kind particularly adapted for use in electrical heating devices of the pressure plate or fiat surfaced type.

various mechanicalV connec# l Y card orpadfof fibrous fiiiate'rial, such as A heating element constructed 'according to this invention is illustrated in the accompanying drawings as applied to a flat ironof triangular shape, but it will be understood that it is equally adapted to be used with other electrically heated devices such as hot plates, disk heaters,` serving; trays, ctc., either of rectangular, square, circular or other form. y v

In the draWings-Figureul-is a side elevation, partly sectional, of afflat iron equipped withv al heating element constructved according to this invention.; -Fig. 24r isa ,plan view of theheat-ing' ele'r'nent.' 'Figf is an enlarged fragmentary sectional fdetail taken on the line A- -'A of Fig. 2.- Fig. 4 is an enlarged fragmentary-sectional detail taken onthe line-B-BfofFig. 2. l

.I nthe con tru'ctrn shown in the diawiings, the heating Vels'ament isnformed off two coils of resistance material-1in thefforin of ribbon. The ribbon 'is Wound onv the lcards or strips 2 of insulating lI'Ii'aterial which A.

may be of any suitable material, A'herein shown ,as mica, the windingsfterminating at the ends of the cards. The' windings 'of the; heating elementare s'ecuredlin their lated supporting card 3, so that,y they may be handled as affunitlin` their assembled form.- For this purposeI'prefer to usea asbestos, for the yreason that mica is quite expensive and when constantly subjected to high temperatures has a tendency to disintegrate. B v coating the pad and impregnating the same more or .less withi an 'earthy material orl lillerof thenature of an insulating compound 4. it permits the use of a much poorer gradeY of asbestos or other fibrous material thanfwouldotherwise be possible if the windingfand padL were placed in direct contact.4 Thejinsulating compound the supporting pad 3 is made at the terminal ends of the windings. This connection includes an eyelet 5 secured to the asbestos pad 3 previous to its being coated.A with the insulating compound 4. A v,second and longer eyelet 6 together with the adjacent ends of the ribbons 1, extends through the first eyelet 5 as shown in Fig. 4. Awasher 7 is placed over the upper end of the eyelet and the ends of said ribbons extend above it and are held thereagainst by said eyelet- The eyelet 6 is crimped, swaged or headed so as to secure all the parts firmly together, thereby gripping the cards 2 and'V 3 l'firmly' between the washer 7 and the flange 6 of the eyelet 6. A flat headed screw 8 extends `through the eyelet 6 and has a nut?) lirmly lscrewed down thereon so as to further secure the connection. Withthe windings so attached tothe supporting card 3 they may be conveniently handled for the purpose ot assembling, `dis mantling or for transportation. In order to use this heating element, it is,go f course, necessary to have a suitable 'liousipngwithin which it is to bef mounted, which housing constitutes the electrically heated device.' In the specific embodiment -herein illustrated this housing is shown in the'iform ofnaltlat iron comprising a heating plate 10 having' a' polished surface 11 and a protecting casing 12 secured to the plate' 10. The vinner face of the heating plate 10 is recessed 'at a uniform depthnearly coextensive with the area of the plate, and the recess is iilled with aninsulating compound 13, preferably spread in the recess in a semiuid or plastic condition, and then allowed to solidify. The heating element rests directly upon this insulating compound 13 and is forced into rm contact therewith by means of the pressure plate 14.

` The `clamping means for securing the pressure plate 14 in position includes a bolt or Srew 15, secured to the boss 16 on the heating plate 10, and extending upwardly through 'the plate 14 to permit the nut 17 to be screwed down against the plate 14. '.llhe'bolt l5 extends to the exterior of the casing 12 to permit the nut 18 to be screwed thereon for clamping the casing A1Q to the :plate 1'0. A

The electric conductors 19 are led into the housing in any suitable manner so as to be connected to the screws 8, which also serve binding posts. In the embodiment here- 4 in shown, the conductors enter at the rear o the handle 20 through a tubular extension t,2 1 andpass down through the support 22. The ends of the conductor wires are looped and passed over 'the screws 8 above the nuts @and secured thereto by means of the nuts23.

Although but one specific embodiment of 'this invention has 'been 'herein shown and described, it will be understood that numero'iis details `o'l the construction shown may EST Aiiaaete cos` be altered or omitted without departing from the spirit of this invention as defined by the following claims.

I clai1n:-

1. In a device of the class described, a

heating. plate, a pressure plate, a heating element between them, and insulation between said heating element and one of said plates, said insulation comprising a pad of soft fibrous material containing and coated with earthy insulating filler material on the side adjacent to the heating element. 2. In a device of the class described, a heating plate, a pressure late, a heating element between them, and) insulation between said heating element and one of said plates, said insulation comprising a pad of light 'asbestos impre ated and coated with earthy insulating l er material.

3. An electric heating device, comprising a metallic heating plate having its back side coated with a layer of insulating compound, an' electric heating element behind said coated side, a pressure `plate behind said heating element, a fibrous flexible pad impregnated with earthy material and interposed between said heating element and said pressure plate and means for holding saidpressure plate and heating plate in ,clamping engagement `with said heating 'element and pad.

4. An electric heating device, comprising a latlheati'ng plate coated on one side with al layer of insulating compound, a llat elec-- tricl elemently'ing` against said coated side of said plate, a: pressure plate behind said heating element, a thin flexible pad of po- A ing engagement with saidheating element.

5. In a device Vofthe class described, a heating plate, a pressure plate, a heating element between them, and insulation between said heating element and both of said plates, the insulation between said ressure plate and heating element comprising a pad of soft fibrous heat insulating material coated and impregnated with earthy insulating filler material on 'the side adjacent to said heating element, and the insulation between lsaid heating plate and `said heating element comprising a coating of hard-set earthy material on said heating plate.

6. In an electric heater, the combination of a heat-ing plate, a pressure plate, a 'heating element interposed between said plates, 'a hollow casing surrounding .said pressure plate and heating element and coactingwith said heating plate to form 'a housing therefor, 'and a single 'Stud bolt having a 'of nuts thereon, one being adapted "to secure im BEST AVAILABLE COP.

said casing in position on said heating plate, and the other' being adapted to draw said pressure plate and heating plate into clamping engagement with the heating element, said heating plate and casing being formed and adapted for coengageinent to prevent relative turning on said stud.

7. In a device of the class described, a body element adapted for the reception and transmission of heat, in combination With a heat generating and distributing element comprising a plurality of small electric conductors of low conductivity and disposed in distributed relation Within said body and connected together at each end substantially integrally7 parallel for electrically heating said body, each connection comprising in` nel' and outer concentric bushings adapted and arranged for holding the terminals riOidly clamped therebetween, and a terminal stud adapted to be secured rigidly in said bushings.

Signed at Detroit this 7th day of September, 1912.

CHARLES P. MADSEN. Vitnesses:

EMMET DWYER,

WILLIAM J. KEEP.

Copie: of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents, Washington, D. C.

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