US1415829A - Thermostatic circuit closer for laundry irons - Google Patents

Description

I I APPLICATION FILED IULYI6,I9I9. 1,415,829.

. A. E. FITZGERALD. THERMOSTATIC CIRCUIT CLOSER FOR LAUNDRY IRONS.

Patented May 9, 1922.

J32 Uen Z0 417132 2 ger 1 tion.

UNITED STATES PATENT OFFICE.

Specification of Letters Patent.

' THERMOSTATIG orzaoorr cizosna non LAUNDRY IRo s Patented May 9, 1922.

Application filed July 16, 1919. Serial No. 311,287.

T 0 all whom it may concern Beit known that I, ARTHUR ERNEST FITZ- GERALD, a citizen of the Dominion of New Zealand, residing at Wellington, inthe Provincial District of Wellington, have in vented certain new and useful Improvements in Thermostatic Circuit Closers for Laundry Irons, of which the following is specifica- This invention relates to laundry irons heated by electric current, and provided with a coiled switch element mounted in the base forming part of the electric circuit'of the iron, and adapted to break the circuit when the temperature reaches a predetermined limit.

The object of the invention is to provide an improved construction of contact switch and operating means for the aforesaid purpose and more particularly to enable the operating means to be adjusted to the switch, whereby the predetermined maximum limit of temperature of the iron can be regulated to suit the material on which the iron is to be used. 1

According to the invention the spring switch forms part of the electric circuit of the iron, and is normally closed.

An operating member which derives its heat from the iron and formed wholly or partly of metal or material adapted to expand under the influence of heat is adapted by its expansion to move the switch to cause a break in the circuit within the laundry iron, when a predetermined degree of temperature is reached, whereupon the current ceases to pass and the temperature of the iron falls.

The contraction of said operating member on the temperature receding permits the switch to close the break in the circuit and the current to again pass.

In order to effect the breaking of the circuit at any desired degree of temperature, the operating member is made adjustable to the switch by means of a screw operable from without the iron.

By these means the degree of temperature which it is desired shall not be exceeded, can be determined before commencing to use the iron, as forinstance, to iron certain material it is found necessary to increase the temperature, whereupon the operating member is moved by means of the adjusting screw further from the witch or so as to necessitate a higher degree of temperature being reached before said member will expand sufficiently to operate the switch and cause a break in the circuit.

lVhen a lower temperature isdcsired the operating member is adjusted closer to the switch or so as to require a lower temperature to cause said'member to expand suiiiciently in order to operate the switch and effect a break in the circuit.

The invention will be more particularly described with reference to the accompanyin drawing, in which *lgure 1 is a plan view of a modification and Figure 2 a sectional elevation on the line 5--5 Figurel.

Referring to Figures 1 and 2 the operating member is in the form of a coil 18 formed wholly of copper or other similar material or metal, said coil 18 being retained in a well 19 of porcelain or other non-conducting and heat resisting material, sunk in the iron base 3.

' The outer end 20 of the coil 18 projects into a recess 21 in the porcelain while the inner end of the coil carries a switch 22 with a terminal 28 thereon kept normally in contact with a terminal 24 on a bracket 25 on and insulated from the base 3 and adapted to be put in electric communication with one of the wires (not shown) of the usual flexible cord of the circuit, the outer end 20 being in practice in contact with one end of the heating element, which is in electric communication with the other wire of the afore said flexible cord.

A screw 26 working through a nut 27 contained in the porcelain wall of the well 19, is attached to the end 20 of the coil 18,'the head 28 of said screw 26 being located ina recess 29.

Under heat the coil 18 expands at a greater ratio than the wall in which it is contained and as the outer end 20 is held by the screw 26 the inner end moves and the terminal 23 becomes separated from the terminal 24: and the electric circuit is thereby broken to prevent the temperature exceeding that required.

By adjusting the screw 26 the degree of expansion necessary to operate the switch 22 to cause a break in the circuit can be increased or decreased according to the degree of temperature it is desired shall not be exceeded.

Claims:

1. In an electric laundry iron, a coiled operating member forming part of the circuit by which the iron is heated, a Well oi nonconducting and heat-resisting material containing said coiled member, a contact secured to the inner end of said coil, a bracket Secured on and insulated from the base oi said iron, a contact mounted on said bracket and adapted to be engaged by the contact on said coiled member, and means engaging the outer end of the coiled member for adjusting it Within said Well.

2. In an electric laundry iron including a base formed With a recess, a Well of non-conducting and heat-resisting material mounted in said recess, a coiled thermostatic member forming part of the heating circuit of the iron mounted in the recess so that the outer coil has its surface in contact with the Wall oi? the well, a contact element secured to the inner end oi? the coiled member, a bracket secured on and insulated from the base of said iron, a contact mounted on said bracket and adapted to be engaged by the contact element on said coiled member, and means engaging the outer end of the coiled member for moving the coil with respect to the Well.

3. In an electric laundij'y iron, a coiled operating member forming part of the ci1= cuit by which the iron is heated; a- Well of non-conducting and heat resisting material containing said coiled member; a contact secured to the inner end bracket secured on and insulated from the base of said iron; a contact mounted on. said bracket and adapted to be engaged by the contact on said coiled member, and a screw for adjusting and holding the outer end of said coiled member, substantially as described and illustrated.

In testin'iony whereof I aliix my sigi'iature.

ARTHUR ERNEST FITZGERALD.

of said coil; a

Images