US2595243A - Supporting device for electrical heating appliances - Google Patents

Description

May 6, L, SUPPORTING DEVICE FOR ELECTRICAL HEATING APPLIANCES Filed Feb. 21, 1949 2 SHEETSSHEET 1 INVENTOR.

H. L. GORDON May 6, 1952 SUPPORTING DEVICE FOR ELECTRICAL HEATING APPLIANCES Filed Feb. 21, 1949 2 SHEETSSHEET 2 Patented May 6, 1952 ()FFICE SUPPORTING DEVICE FOR ELECTRICAL HEATING APPLIANCES Herman L. Gordon, Silver Spring, Md.

Application February 21, 1949, Serial No. 77,607

1 7 Claims.

This invention relates to support devices for use with flatirons, and more particularly for use with electric irons.

A main object of the invention is to provide a novel and improved flatiron support of the self-heated type which may be employed also as a warming device for food and the like, said support being very simple in structure, compact in size, and providing a means of protecting the heating winding of an electric iron when employed therewith.

A further object of the invention is to provide an improved support for electric irons, which greatly increases the life of the heating winding of an iron by automatically reducing the voltage applied to said winding when the iron is placed on the support, yet at the same time providing a source of heat for maintaining the iron at its rated working temperature.

A still further object of the invention is to provide an improved supporting rest for electric flatirons which is adapted to automatically reduce the current load in the iron heating winding when the iron is placed on the rest and at the same time to furnish heat to the iron to maintain its required operating, temperature, the structure employed requiring only a few simple parts which are inexpensive to fabricate and to assemble.

A still further object of the invention is to provide an improved safety device for supporting an electric iron when it is not in immediate use, said device reducing the electrical current load on the heater winding of the iron during this inactive period and thereby prolonging the life of said winding, the device also functioning to prevent the iron from cooling to an undesirable low temperature during said inactive period so that the iron will always be ready for use when the ironing process is resumed.

Further objects and advantages of the invention will become apparent from the following description and claims, and from the accompanying drawings, wherein:

Figure 1 is a longitudinal cross-sectional view taken through a self-heated support device for a electrical connections employed in the iron support device of Figure 1-.

Referring to the drawings, l I designates a base plate which may be of any desired shape and is illustrated by way of example as being rectangular. Secured to the bottom of base plate I l adjacent its respective corners are supporting feet l2 of suitable heat-resisting material. Base plate I i is formed with an upturned marginal flange l3 extending around its edges, and secured to said flange is a rectangular shell i4, defining with said base plate a generally rectangular housing. Secured to the shell walls in the corners of the housing and near the top edge of the shell are angle brackets l5, each of which is formed at the center of its horizontal arm with an aperture 16-.

Overlying the top edges of the shell 14 and freely movable vertically with respect thereto is a rectangular top cover I! having a marginal depending fiange i8 extending completely around it and positioned adjacent the upper external surface portions of the shell [4, as shown in Figure l. Secured to the top cover it adjacent its corners are depending bolts !9 which pass through the respective angle bracket apertures [6. Threaded on the lower end portions of the bolts [9 are stop nuts shown at 243, 29, cooperating with the hori' zontal arm portions of the brackets l5 to limit upward movement of the cover ll. Encircling each bolt 19 is a coil spring 2| bearing at its bottom end on the horizontal arm of the associated bracket [5 and bearing at its top end against a nut 22 employed to secure the bolt It to the cover H. The springs 21 therefore urge the cover I! upwardly to an elevated position determined by the adjusted positions of the nuts 20, 20 on the bolts 19.

The cover H is preferably formed with longitudinal corrugations 23, and at the trough portions of the corrugations are formed longitudinally spaced openings 24. The crests of the corrugations preferably are flush with the horizontal top plane of the cover.

Secured to the end walls of the shell 14 are vertically spaced brackets 25 and 26 of heatresisting insulating material, such as porcelain or the like. Each bracket 25 and 26 is formed with spaced apertures 2?. Secured to the lower brackets 25, 25 is a first resistance winding 28 which is looped through the apertures 21 of the brackets so that the winding is suspended inside the shell. Secured in a similar manner to the upper brackets 26, 25 is a second resistance winding 29 looped through the apertures 21 of the brackets 25, 26, as shown in Figure 2, whereby said second winding is'suspended above the first winding 23 in a plane parallel to and vertically spaced above said first winding. The resistance windings 28 and 29 are of suitable heat resistant wire such as the coiled heating wire commonly employed in electrical heating devices.

Secured to the forward wall of the shell I4 is an angle bracket 30, preferably of heat-resistant insulating material. Secured on the horizontal arm of bracket 30 by a bolt 3| and suitable heatresistant insulating washers 32 are parallel spaced resilient metal spring arms shown respectively at 33, 34 and 35. The intermediate spring arm 34 extends a substantial distance beyond the ends of the upper and lower spring arms 33 and 35. Spring arm 34 normally engages upper spring arm 33, suitable contact points being provided at the points of engagement of said spring arms. Secured to the cover I! above said spring arms is a member 36 of suitable heat-resistant insulating material having a depending projection 3'! adapted to engage the end of spring arm 34 when the cover I! is moved downwardly. When this occurs, spring arm 34 moves out of contact with spring arm 33 and engages the lower spring arm 35, suitable contact points being provided at the respective points of engagement of the spring arms 34 and 35.

Secured to the forward wall of the shell is a second angle bracket 38 of heat-resistant insulating material, on the horizontal arm of which are secured by means of a bolt 39 and heat-resisting insulating washers 40 a pair of parallel resilient metal arms 4| and 42, normally vertically spaced apart at their ends, as shown in Figure 1. Secured to the cover I! above said resilient arms is a member 43 of heat-resistant insulating material having a depending projection 44 adapted to engage the upper spring arm 42 when the cover is moved downwardly. When this occurs, the arm 42 is moved into contact with the lower arm 4|, suitable contact points being provided on said arms at their points of contact.

Secured to the front wall of the shell I! and projecting through a suitable notch formed in said front wall is a conventional female receptacle 45. Extending through an insulating bushing 46 in the rear wall of the shell I! is a line cord 41.

Referring now to Figure 4, one of the line cord wires, shown at 48, is connected to one of the terminals 49 of the female receptacle 45. A wire 50 connects the lower spring arm 4| to wire 48. The upper spring arm 42 is connected by a wire 43' to one end of the resistance winding 28. The other line cord wire, shown at is connected to upper spring arm 33. The intermediate spring arm 34 is connected by a wire 52 to the remaining terminal 53 of the female receptacle 45. The remaining end of resistance winding 28 is connected to wire 52. One end of resistance winding 29 is connected to line wire 5l and the other end thereof is connected to the lower spring arm 35.

It will thus be seen that when the electric iron, designated at 54, is plugged into the receptacle 45, and. the parts are in their normal positions, such as shown in Figure l, the full line voltage will be impressed on the heating winding of the iron through a circuit comprising line wire 5|, spring arm 33, spring arm 34, wire 52, terminal 53, the iron 54, terminal 49, and line wire 48.

When the iron is placed on the cover i1 during a period of inactivity, the cover I1 is moved downwardly by the weight of the iron, whereby the projections 31 and 44 depress the respective spring arms 34 and 42, as above described. Spring arm 34 then engages spring arm 35 and spring arm 42 engages spring arm 4|. This shunts resistance winding 28 across the iron heating winding and places resistance winding 29 in series with the shunted circuit. Current then flows from 1ine wire 5|, through resistance winding 29, spring arm 35, spring arm 34, wire 52, and through the parallel circuits comprising the iron 54 and the resistance Winding 28. The shunt circuit for resistance 28 is closed at spring arm 42 and spring arm 4|, thereby being connected to wire 50 and line wire 48.

The voltage drop at resistance 29 substantially reduces the voltage across the iron 54, causing a reduced current to flow through the iron. At the same time, the current flowing through the re sistance windings 29 and 28 produces heat which prevents the temperature of the iron from dropping below a desired working temperature.

The following is an analysis of the operation of a typical design of an appliance constructed in accordance with the foregoing description:

Let W0 be the dissipative wattage rating of the iron.

Assume that in the typical design under con sideration where N is a value to be determined, and from Equation 5, defines the ratio of R1 to either R28 By analyzing the above defined series-parallel circuit it can readily be shown that Dividing through by V0 expanding, and clearing fractions gives:

The value of N satisfying Equation 9 is N =1.62 (very closely) or R29=R-28:.618Ri, and V1 from Equation 7 is .382V0.

Under these conditions, the voltage across the iron heater winding has been reduced to approximately 38% of its normal value without loss of heat.

When the appliance is employed as a food warmer, the load 54 is absent in Figure 4, and when a dish of food is placed on the support I1, the weight of the dish moves support ii downwardly and causes spring arm 34 to engage spring arm 35 and spring arm 42 to engage spring arm 4!. This connects heater windings 28 and 29 in series across the line.

Assuming, as before, that the wattage Wr dissipated by the device employed now as a food warmer will be given by In the typical design above discussed the value of N is 1.52. Therefore Thus, in the typical design under consideration the Wattage rating as a food warmer will be 81 percent of the flatiron wattage rating. Of course, a particular design of the device may be employed with substantially equal efiectiveness with flatirons of various wattage ratings. Also, the values of the resistances of the respective heater windings 28 and 29 may be varied to suit practical design requirements.

While a specific embodiment of a combined self-heating flatiron support and food warmer has been disclosed in the foregoing description, it will be understood that various modifications within the spirit of the invention may occur to those skilled in the art. Therefore it is intended that no limitations be placed on the invention except as defined by the scope of the appended claims.

What is claimed is:

1. An appliance of the character described, comprising a housing having a movable top member, spring means biasing said top member upwardly, a first heater winding and a second heater winding in said housing, both of said heater windings being arranged in heat-transmitting relation to said top member, first and second line wires entering said housing, first and second switches in said housing, each having a movable contact element engageable by said movable top member and a stationary lower contact normally out of engagement with the movable element but engageable by said movable contact element when it is moved downwardly, the first switch having a stationary upper contact normally engaged by the movable contact element of said first switch, said upper contact being connected to the first line wire and the lower contact of the second switch be ing connected to the second line wire, the first heater winding being connected across the movable contacts and the secondheater winding being connected across the stationary lower contact of the first switch and the stationary upper contact thereof, whereby the heater windings are normally out of circuit with respect to the line wires but are placed in series across the line wires when the movable contacts engage their lower stationary contacts responsive to depression of said top member, and a female receptacle connected between the movable contact element of the first switch and the stationary lower contact of the second switch, and whereby an electrical heating appliance may be connected to the device and its degree of energization modified by placing it on the movable top member.

2. An appliance oi the character described comprising a housing having a movable top member, means biasing said top member upwardly, first and second heater windings in said housing, both of said heater windings being arranged in heat-transmitting relation to said top member, first and second line wires entering said housing, first and second switches in said housing, each having a movable pole biased upwardly, means transmitting downward force to the movable poles from said movable top member, each switch having a stationary lower contact normally out of engagement with the associated pole but engageable by the pole when it is moved downwardly, the first switch having a stationary upper contact normally engaged by the pole of said first switch, said upper contact being connected to the first line wire and the lower contact of the second switch being connected to the second line wire, the first heater winding being connected across the poles and the second heater winding being connected across the stationary contacts of the first switch, whereby the heater windings are normally out of circuit with respect to the line wires but are placed in series across the line wires when the poles engage their lower stationary contacts, and a female receptacle connected between the pole of the first switch and the stationary lower contact of the second switch, and whereby an electrical heating appliance may be connected to the device and its degree of energization modified by placing it on the movable top member.

3. In combination with an electric fiatiron, a housing having a movable top member, means biasing said top member upwardly, first and second'heater windings in said housing, both of said heater windings being arranged in heattransmitting relation to said top member, first andsecond line wires entering said housing, first and second switches in said housing, .each having a movable pole biased upwardly, means transmitting downward force to the movable poles from said movable top member, each switch having a stationary lower contact normally out of engagement with the associated pole but engageable by the pole when it is moved downwardly, the first switch having a stationary upper contact normally engaged by the pole of said first switch, said upper contact being connected to the first line wire and the lower contact of the second switch being connected to the second line wire, the second heater winding being connected across the stationary contacts of the first switch and the first heater winding being connected across the poles, whereby the heater windings are placed in series across the line wires when the poles engage their lower stationary contacts, and circuit means connecting the fiatiron between the pole of the first switch and the stationary lower contact of the second switch.

4. In combination with an electrical heating appliance, a base, a support element movably mounted on said base, means biasing said support element upwardly, first and second heater windings arranged in heat-transmitting relation to said support element, first and second line wires, first and second switches on said base, each having a movable pole biased upwardly, means transmitting downward force to the movable poles from said support element, each switch having a stationary lower contact normally out of engagement with the associated pole but engageable by the pole when it is moved downwardly, the first switch having a stationary upper contact normally engaged by the pole of said first switch, said upper contact being connected to the first line wire and the lower contact of the second switch being connected to the second line wire, the second heater winding being connected across the stationary contacts of the first switch and the first heater winding being connected across the poles, whereby the heater windings are placed in series across the line wires when the poles engage their lower stationary contacts, and circuit means connecting the heating appliance between the pole of the first switch and the stationary lower contact of the second switch.

5. A device of the character described comprising a base, a support element movably mounted on said base, means biasing said support element upwardly, first and second heater windings arranged in heat-transmitting relation to said support element, first and second line wires, first and second switches on said base, each having a movable pole biased upwardly, means transmitting downward force to the movable poles from said support element, each switch having a stationary lower contact normally out of engagement with the associated pole but engageable by the pole when it is moved downwardly, the first switch having a stationary upper contact normally engaged by the pole of said first switch, said upper contact being connected to the first line wire and the lower contact of the second switch being connected to the second line wire, the second heater winding being connected across the stationary contacts of the first switch and the first heater winding being connected across the poles, whereby both heater windings are normally out of circuit with respect to the line wires but are placed in series across the line wires when the poles engage their lower stationary contacts, and a female receptacle connected between the pole of the first switch and the stationary lower contact of the second switch, whereby an elec- 8 trical heating appliance may be connected to the device and its degree of energization modified by placing it on the support element.

6. A device of the character described comprising a base, a support element movably mounted on said base, means biasing said support element upwardly, first and second heater windings arranged in heat-transmitting relation to said support element, a female receptacle, first and second switches mechanically coupled to said support element, first and second line wires, the first line wire being normally connected through one of the switches to one terminal of the receptacle, first circuit means, including the first switch, arranged to disconnect said first line wire from said one terminal and connect the first heater winding between the first line wire and said one terminal of the receptacle responsive to depression of the support element, and second circuit means, including the second switch, arranged to connect the second heater winding across the receptacle responsive to said depression of the support element, the second line wire being connected to the other terminal of the receptacle, whereby the current through an electrical device plugged into the receptacle will be modified when the said electrical device is placed on the support element.

7. A device of the character described comprising a base, a support element movably mounted on said base, means biasing said support element upwardly, first and second heater windings arranged in heat-transmitting relation to said support element, a female receptacle, a pair of line wires, circuit means normally connecting said line wires to said receptacle, and switch means mechanically coupled to said support element, said switch means being formed and arranged to simultaneously connect the first heater winding in shunt with said female receptacle and said second heater winding in series with said line wires responsive to depression of said support element, whereby the current through an electrical appliance plugged into the receptacle will be modified when the appliance is placed on the support element.

HERMAN L. GORDON.

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

UNITED STATES PATENTS Number Name Date 723,633 Ayer Mar. 24, 1903 748,572 Ayer Jan. 5, 1904 925,050 Sprenger June 15, 1909 2,134,805 Sessions Nov. 1, 1938 2,405,270 Reiss Aug. 6, 1946

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