US 2449317 A
Description (OCR text may contain errors)
Sept. 14, 1948. E. c. PlTMAN ELECTROSTATIC PRESSING APPARATUS Filed April 18, 1944 11am Z'ar-Ze Q. Plat/nan wmy Patented Sept. 14, 1948 PATENT OFFICE ELECTROSTATIC PEESSING APPARATUS Earle C. Pitrnan, Red Bank, N. J., assignor to Compo Shoe Machinery Corporation, Boston, Mass, a corporation of Delaware Application April 18, 1944, Serial No. 531,533
2 Claims. (01. 219 -19) apparatus and more particularly to hand irons providing electrostatic heat for pressing and drying damp cloth and the like.
The ordinary hand iron to be effective has to have its ironing surface at such a high tempera ture that the material being ironed may easily be scorched or burned.
This invention provides an ironing surface having a plurality of spaced electrodes therebeneath, alternate of said electrodes being connected to opposite sides of the output circuit of a high frequency oscillator. The electrodes individually, extend crosswise the ironing surface and collectively, extend the length of the surface. Electrostatic fields are set up between the electrodes under the ironing surface, and when a damp cloth is placed upon the ironing surface, the cloth acts as a dielectric in the electrostatic fields and is heated by hysteresis action. The power absorbed by the cloth from the electrostatic fields and, therefore, the heat produced in the cloth, is proportional to the moisture content of the cloth.
An ordinary, but unheated, hand iron having a metal lower surface is used to press the damp cloth. The lower surface of the iron acts as a free electrode when the iron is placed upon the cloth, the electrical capacity between the free electrode and the electrodes under the cloth causing an electrostatic field to be produced between the iron and the electrodes over which it is placed, which is considerably more intense than the electrostatic field produced between adjacent electrodes under the cloth. Thus as the iron is moved over the cloth, sufficient heat is produced in the cloth it contacts, for the desired effect.
The ironing surface of the iron is not heated so that it may be left upon the surface of the cloth being ironed, for any period of time without any scorching or burning of the cloth.
Another advantage is that no trailing wires are attached to the hand ironer.
An object of the invention is to provide electrostatic heat through the use of a hand iron.
Another object of the invention is to utilize the metal under surface .of a hand iron as a free electrode in an electrostatic field for providing heat in material being ironed.
The invention will now be described with reference to the drawing which is a projected view of an ironing table having an oscillator therein, and having interlaced electrodes under its work supporting surface connected to the oscillator,
and of a hand iron, the lower metal surfaceef which forms a free electrode.
The table illustrated has the doors it which provide access to a conventional high frequency oscillator 6 supported within the table. 7
The top 1 of the table is of electrical insulating material and has contained therein as by molding, the electrodes 8 and the electrodes 9 which are spaced from the electrodes 8 and which with same, extend crosswise the table top 1. The electrodes B are interconnected by the electrical conductor H) which in turn, is connected by the wire II to one side of the output circuit of the oscillator 6. The electrodes 9 are interconnected by the conductor l2 and are connected by the wire l3 to the other side of the output circuit of the oscillator 6.
, The hand iron 14 which may be a conventional metal iron or one having a metal bottom, is used to press damp cloth placed upon the top I of the table. With the oscillator 6 energized, a relatively intense electrostatic field is produced between the lower suriace of the iron and the electrodes 8 and 9 over which it is placed. This causes sufficient heat to be generated in the cloth under the iron as it is moved over the cloth as is usual in ironing, for the desired pressing and drying to be accomplished.
The switch arm I5 is connected at its inner end to the usual energizing switch in the oscillator 6 and is pivoted at its outer end to the lower end of the vertically extending rod l6, upon the upper end of which is attached the disc IT. The rod 16 passes through and is supported by the plates 18 attached to the table. The spring i8 is attached to the rod l6 and is compressed against the lower plate l8 when the iron I4 is placed on the disc IT as illustrated. The switch arm [5 opens the oscillator energizing switch at this time. When the iron M is removed from the disc H, the spring l9 moves the rod l6 and the switch arm i5 upwardly and closes the oscillator energizing switch.
Thus when the iron I4 is not in use, it may be placed upon the disc I! which serves as an iron stand, for automatically deenergizing the oscillator.
It is preferred that the oscillator 6 be of the push-pull type disclosed in the E. L. Crandell U. S. Patent No. 2,298,038. With this type of oscillator, a free electrode is maintained at ground potential so that there can be no voltages induced on any surface of the iron l4 and no harm caused by electrical shock, to the operator of the iron.
While one embodiment of the invention has been described for the purpose of illustration, it should be understood that the invention is not limited to the exact apparatus and arrangement of apparatus illustrated, as modifications thereof may be suggested by those skilled in the art without departure from the essence of the inventlon.
What is claimed is:
1. Ironing apparatus comprising in combination, an oscillator, a cabinet housing said oscillator, said cabinet providing a support for the material to be ironed, a plurality of spaced electrodes embedded within said support, repair of electrical conductors connecting the alternate of said electrodes together, means connecting said conductors to the output circuit of saido'scillator, and a hand iron having a metallic lower surface providing a free electrode capacitively coupled to said electrodes when said iron is brought into ironing contact with the material placed upon said support.
'2. Ironing apparatus comprising, an-oscillator, a'h'ousing for said oscillator, a slab-like support providing an ironing surface, said housing being disposed immedi'atelybelow and attached to the under side of said support, a plurality of spaced electrodes embedded within said support near the ironing surface thereof, a pair of electrical conductors connecting the alternate of said electrodes together, means connecting said concluctors to the output circuit of said oscillator, and a hand iron having a metallic lower surface providing a free electrode capacitively coupled to said electrodes when said iron is brought into ironing contact with the material placed upon said support.
EARLE C. PITMAN.
REFERENCES CITED The following references are of record in the file of thispatent:
UNITED STATES PATENTS Number Name Date 1,681,132 Reynolds Aug. 14, 1928 2,133,494 Waters Oct. 18, 1938 2,137,189 Whitman Nov. 15, 1938 2,212,522 Hart et al Aug. 27,1940 2,226,871 Nicholas Dec. 31, 1940 2,298,038 Crandell Oct. 6, 1942