US2307052A

US2307052A - Circuit control for electric flatirons and connection therefor

Info

Publication number: US2307052A
Application number: US353908A
Authority: US
Inventors: Louis V Lucia
Original assignee: Silex Co
Current assignee: Silex Co
Priority date: 1940-04-23
Filing date: 1940-04-23
Publication date: 1943-01-05
Anticipated expiration: 1960-01-05

Description

1943- L. v. LUCIA I 2,307,052

CIRCUIT CONTROL FOR ELECTRIC FLATIRONS AND CONNECTION THEREFOR Filed Aug. 25, 1940 IN VEN TOR.

Patented Jan. 5, 1943 I CIRCUIT CONTROL F IRONS AND CONNE Louis V. Lucia, West Hart The Sllex Company, ration of Connecticut OR ELECTRIC FLAT- CT'ION THEREFOR ford, Conn., assignor to Hartford, Conn., a corpo- Application August 23, 1940, Serial No. 353,908

11 Claims.

This invention relates to circuit control for electric flat irons and connection therefor, and is particularly intended for steaming and pressing irons as shown and described in the co-pending application of Frank E. Wolcott, Ser. No. 337,279, filed May 25, 1940, and assigned to the assignee hereto.

In devices of this type, it is very important that the temperature thereof be maintained within a variation of only a few degrees of the operating temperature which is desired, and that the thermostatic device for maintaining said temperature be so constructed that it will not become affected, under such conditions as when exposed to a high temperature in the said device, and will in sure stability in the operation of the said device.

The object of the invention, therefore, is to provide a highly efficient circuit control of the thermostatic type for selectively maintaining a desired temperature in a pressing iron.

A further object of the invention is to provide a novel electrical connection for the heating element of a pressing iron, which is highly desirable in the use of such irons as well as in the manufacture thereof. 1

Further objects of the invention will be more clearly understood from the following description and from the accompanying drawing in which:

Fig. 1 is a side view, partly in central vertical section, illustrating my invention as embodied in an electric pressing iron.

Fig. 2 is a plan view of the said iron with parts thereof omitted to show the control embodied in my invention.

Fig. 3 is a side view in vertical section on line 33.of Fig. 4 showing the construction of said control and its connection in an electrical circuit.

Fig. 4 is a plan view thereof.

As illustrated in the drawing, the numeral! denotes the casing, or body, of a pressing iron having a sole plate 6 and a handle 1.

In the construction shown, a cover plate 8 may be provided for sealing the water-heating chamber 9, within the casing 5, and the said cover may have projections, such as In, extending therefrom for securing the handle 1 thereto. 7

The cover 8 may be extended beyond the back of the casing so as to provide in said iron a control chamber it within which my improved circuit control may be contained so that it will not be subjected to the high heat to which thermostatic controls for such iron have heretofore beensubjected in order that sufficiently accurate respons from such controls to the temperature of the sole plate may be obtained.

My improved control, as shown, for controlling anelectric circuit which supplies current to a heating element 6a for heating the sole plate and. water chamber 9, comprises an upright frame i2 which is mounted upon the upper surface of the sole plate 6 upon a surface that is adapted to support said plate in a slanted position to conform with the design of the particular iron illustrated.

An electrical contact member i3, electrically connected to the frame I2, is carried upon a shaft l4 that is rotatable in said frame and has a head IS, with a flat i 6, to which is secured an operating knob H, with an indicating pointer I8 thereof, for rotating said shaft to position the contact cam i 3 for the degree of heat required.

A spring bar 19 issecured to the bottom of said frame It by means of a supporting bar 20 which is insulated from said frame by mica plates 2|; the plate 22 insulating the entire assembly from the sol plate 6, and the said frame, supporting bar and insulating plates all being secured into a complete'unit by means of eyelets 23 through which extend the screws 24 that are threaded into the sole plate 6 for securing the frame I2 thereto.

The spring bar 1 9 is provided with a contact point 25 for engaging the contact cam l3 and also with a laterally extending arm 28 to which is threaded an adjusting screw 21 having an insulating point 28 in contact with a bi-metal bar 29 that is secured directly to the sole plate 6 and operates in response to the temperature thereof as will be hereinafter more fully described.

My invention also includes an electrical connection for saidcontrol whereby electrical conductors, including a wire 30 which is connected to the frame I 2, and a wire 32, which is connected to the lead wire 6--b of the heating element 6a, extend from said control through an opening 33 in the cover 8 into a compartment 34 in the handle 1, and therefrom, through an opening 35 in the back of said handle to the exterior of the iron so that said wires, which may be included in a cord 36, may be connected to an electrical outlet.

The lead wire 6-0, at the opposite side of the heating element, may be connected to an extension 3| on the bar 20 which is electrically connected to the spring bar l9.

If desired, a sleeve 31 may enclose said cord adjacent to said handle, in order to relieve the cord of undue strain, and the said sleeve may be secured to the handle by means of a head 39 which forms a head engaging the peripheral portion of 011117, the knob l1 the opening 35 in the handle. A strain relief 39-41 may also be attached to said cord to engage the surface of the head 39 and thereby anchoring said cord to the iron so as to prevent strain at the points where the wires 3| and 32 are connected to the control within the chamber H.

In the embodiment illustrated, the handle 1 is preferably constructed of two halves which are secured to the member ID by screws 40 and retained in rigid position by dowels 4|, so as to facilitate the manufacture of said handle as well as the assembling of the above described connection within the chamber 34.

In the operation of my improved control, the knob I1 is first rotated to the desired position, which may be selected from the indicia on the plate 42 by pointing thereto with the pointer 8. The adjustment of said knob will rotate the con- I3 so that it will engage the contact point 25, thereby closing the electric circuit through the heating element and thus causing said element to become energized and heat the sole plate 6 of the iron. This will flex the bimetal bar in an upwardly direction until it'engagesthe point 28 of the screw 21 and thereby,

u when the said sole plate has reached the proper temperature, flex the spring bar ii! in a direction away from the contact i3 so as to separate the contact 25 therefrom and break the electrical circuit through the heating element.

Upon cooling of the said plate to an extent, the said bi-metal member 29 will flex in a downwardly direction and permit the contact 25 to again engage the contact [3 and thereby close the electric circuit; thus controlling the energizing of the heating element in response to the actual temperature in the sole plate 6 of the iron.

When it is desired to manually break the cirmay be turned in a counterclockwise direction, to an off position indicated on the plate 32, wherein the contact l3 will be positioned relative to the contact 25 with the flat 42 thereon providing a space between said contact members; it being of course understood that upon the turning of the knob I! to the desired temperature the said fiat will be rotated so that the circuit will be closed by engagement between the contact members.

From the above description it will be clearly seen that I have provided a thermostatic control which may be located in a portion of a flat iron wherein there is a lower degree of heat than in the sole plate itself and which, due to the novel elements and construction of said control, the same will be responsive to the temperature in the sole plate in a highly sensitive manner; thereby assuring longer life for said control than is possible to attain where controls are mounted between the bottom of the iron and the sole plate, or in other close relation to said sole plate, so as to obtain accurate response to variations in temperature therein, as commonly done in conventional forms of thermostatically controlled pressing irons.

It will further be seen that I have provided novel means whereby a control including parts, of such as spring metal, which aresubject to distortion by repeated subjection to high temperatures, may be positioned in a portion of a device where they are exposed to a lower temperature than the actual operating temperature of said device and so that it may still be operated by a heat responsive member that is in operating portions It is to be understood of the device.

that, while I have shown close heating relation with the 1 pressing iron such as shown, the same may be used in various other types of electrically heated devices without departing from the scope thereof as set forth in the appended claims.

I claim:

1. An electric circuit control comprising a frame, a cam-shaped contact member rotatably mounted in said frame, a resilient member secured to said frame and insulated therefrom, a second contact member on said resilient member, a lateral extension on said resilient member, and adjustable means on said extension engaging a thermally responsive member to operate said resilient member and thereby move the second con- 5 tact member with relation to the rotatable contact member in response to variations in temperatures affecting said thermally responsive member.

2. For an electric heating device, a circuit control comprising a frame having a cam-shaped contact member rotatable therein, a plate secured to said frame by means of eyelets and insulated therefrom, a resilient bar secured to said plate, screws projecting through said eyelets for 5 securing said control to said device, a bi-metallic thermally responsive bar removed from said frame and secured directly to said device, and means ineluding an extension on said resilient bar op-- -erable by said bi-metallic bar for actuating the same.

3. An electric circuit control comprising a frame having a rotatable contact member therein, a movable bar in said frame, means secured in said frame and insulated therefrom'for supporting said 5 movable bar, electric connection means on said bar supporting means, electric connection means on said frame, a thermally responsive member removed from said frame, a lateral extension on said bar, and adjustable means on said extension engageable with said thermally responsive member for the operation of said bar by said thermally responsive member.

' 4. An electric circuit control comprising a frame having a rotatable shaft mounted therein,

a cam-shaped contact member on said shaft,

spacing means on said shaft at one side of the contact member and between said contact member and frame, spring means at the opposite side of and urging said contact member and spacing means in the direction of said frame to frictionally retain said cam-shaped member in adjusted position, a separate contact member engageable with said cam-shaped member, and thermally responsive means for operating said contact member relative to the cam-shaped member.

5. For a device including a heated member, a circuit control comprising an upright U-shaped frame mounted to said member and insulated therefrom, a resilient bar secured to said frame and insulated therefrom, an electric contact carried by said bar, a rotatable shaft mounted in said frame, a cam-shaped contact member carried on said shaft within said frame, friction means between a side of said frame and said cam-shaped member for retaining said member in adjusted position, an extension on said bar, an adjusting screw in said extension, an insulating member in said screw, and a bi-metallic member in direct heating relation with said heated member and engaging said insulating member foractuating said bar to move the contact thereon with relation to the cam-shaped member in response to variations in temperature in said device.

6. For an electric heating device, including a and described my invention as embodied in a heated membenan electric control comprisingan upright U-shaped frame insulated from said member, resilient bar secured to and insulated from the bottom of said frame and extending upwardly therein between the sides of said frame, an electric contact on said bar, a cam-shaped contact member rotatably mounted in and adjacent the top of said frame and disposed between the sides thereof in proximity to the contact on said bar, a thermally responsive member removed from insulated therefrom, an electric contact on said bar, a rotatable cam-shaped contact member between the said extensions and adjacent to the contact member on said bar, a thermally responsive member, and an extension on said bar between the contact member thereon and said base and in position to be engaged by said thermally responsive member to operate said bar.

10.- An electric circuit control of the character said frame and in direct contact with said heateddescribed comprising a frame including a base member, and an extension on said bar having adjustable means in contact with said thermally responsive member for operating said bar and moving the contact thereon relative to the cam having parallel extensions thereon, a resilient bar mounted on said base and insulated therefrom, an electric contact on said bar, a shaft rotatable in said frame, a cam-shaped contact member on shaped contact member in response to tempersaid shaft and disposed between said parallel exature changes in said heated member.

'7. For an electric heating device, a circuit control comprisin an upright frame, a resilient bar secured to said frame and insulated therefrom,

tensions, electric conducting spacing means between said cam-shaped member and frame, spring means between said frame and camshaped member urging said member in the dian electric contact on said bar, a cam-shaped rection of said spacing means and frame, and a contact rotatable in said frame, thermally responsive means responsive to temperature changes in said device for actuating said bar, a

lateral extension on said bar, and adjustable means between saidextension and thermally responsive means.

8. An electric circuit control comprising a 7 frame including'a base having parallel portions extending therefrom, a resilient bar mounted to the base of said frame and insulated'therefrom,

a contact carriedby said bar, a cam-shaped contact member rotatably mounted in said frame and disposed between said parellel portions in proximity to the contact member on said bar, a

said frame, and means extending from said bar and contacting said thermally responsive member for moving the contact on said bar with relation to said rotatable cam-shaped member.

thermostatic bar for operating said resilient bar.

11. For an electrically heated device, a circuit control of the character described comprising an upright U-shaped frame, a shaft extending diagonally to and rotatably mounted in said frame, a cam-shaped contact member carried by said shaft and disposed centrally in said frame between the sides thereof, a bar mounted to the base of said frame and extending upwardly therefrom between the sides of said frame and adapted to contact with said cam-shaped member, a bracket secured to said movable bar at a distance from said base and extending laterally therefrom, a thermally responsive member rethermally responsive member separated from 5 9. An electric circuit control comprising a 40 frame including a base having parallel extensions thereon, a resilient bar mounted to said base and moved from said frame and responsive to temperature changes in said device, adjustable means between said bracket and thermally responsive member for transmiting movement from said member to said bar, and electrical connecting means on said frame and bar.

LOUIS V. LUCIA.