Improvements in Electrically Heated Smoothing Irons.
Year: 1892

page_text: COMPLETE SPECIFICATION.
Improvements in Electrically Heated Smoothing Irons.
I, WILLIS MITCHELL, Electrician, of Malden in the County of Middlesex and
State of Massachusetts, United States of North America, do hereby declare the
nature of my said invention and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement :-
This invention has for its object to improve tailor's irons and other smoothing
devices which are heated by electricity. Heretofore a wire forming part of an
electric circuit has frequently been employed for such purposes, the said wire being
wound on a core in successive coils which are suitably insulated by interposed
sheets or cylinders of asbestos, or by other means. By experiment I find that the
best results are attained when the cores of the heating coils or helices thus wound
are integral with the metal body of the iron or other smoothing device are attached
thereto at one pole. I therefore form the body or bottom plate of the tailor's iron
or other smoothing device with integral magnetic studs on which the coils or
helices of wire constituting the heating devices are wound as above stated.
In the accompanying drawings:-
Figure 1 represents a side elevation of an electrically heated tailor's smoothing
iron embodying my invention, the handle being partly broken away to show the
passage of the insulated wire.
Figure 2 represents a perspective view of the metallic body or bottom plate of
the heater, shewing the studs or posts raised thereon.
Figure 3 represents a similar view shewing the heating devices and bridges in
position.
Figure 4 represents in vertical section one of the heating devices, consisting of
the coiled wire, the interposed layers of asbestos & the stud or post forming their
metallic core.
Figure 5 represents a longitudinal vertical section of the tailor's iron without the
heating devices.
In the said drawings A designates the ordinary wooden grasping piece of the
handle of a tailor's smoothing iron, the metallic frame of said handle consisting
of two counterpart supporting bars B, B', in the upper ends of which the said
grasping piece is journaled by gudgeons b. To allow this journaling, the said
bars curve outward and upward divergently from near the middle. Below this
they are vertical and parallel for a short distance their inner faces being shaped
to form a guide passage for insulating cords c. c. containing the two ends of the
wire C which enters the hollow tailor's iron through an opening in the middle
of its top plate D side by side. The lower ends of bars B B' are provided with
horizontal reversely extending feet 62 which are fastened to the body of the iron
by screws 6 or in any other convenient manner.
The iron is hollow and consists of a solid metallic body or bottom plate E
and the aforesaid top-plate with interposed side walls F of asbestos. These walls
greatly lessen the weight of the implement without impairing its efficiency for
ironing; but they are not absolutely necessary, as the sides of the body E may
be extended up to the said top plate. But when the asbestos walls F are used
as shown these sides are extended up only a little way, forming a peripheral
rim f which affords a base for the said asbestos walls. The metallic body thus
constructed is in effect a bottom plate with a thick raised rim, and a number
of posts or studs in the space which that rim encloses. These studs or posts
are raised on the flat upper face of the said body or bottom plate and are pre-
ferably cast therewith. Like said body, they are magnetic metal.
Two of these posts, marked G are centrally screwtapped on top to receive the

page_text: screws hereinbefore referred to, but have no other use. The other posts, H, are
also screw-tapped to receive screws whereby bridges I are fastened to them.
Each one of these cores or posts H is surrounded by a cylindrical heating device
consisting of a part of the wire C wound in successive concentric helices with
interposed cylinders of asbestos J the wire being preferably naked and wound at
such intervals as I have found to give the greatest heat. The wire is wound first
on the core upward; then downward on the first asbestos cylinder; then upward
on the next; and thus, end for end until a sufficient number of coils have been
provided. The wire then passes to the next post or core H, and this is wound in
like manner, the winding continuing post after post until each core is properly
equipped for heating. The bridges I, which may be of any suitable form or
number or even united in a single plate, serve to keep the heating coils and asbestos
cylinders in place.
When a current of electricity is sent through the wire the cores H are heated as
usual and also magnetized and as the magnetization extends more or less to the
body E a certain amount of heat is generated in the latter by electrical currents
or molecular motions induced thereby, in addition to the heat generated by
resistance of the wire and conducted by the metallic cores into the said body. Thus
the electric current is made to produce heat in at least two ways, and as a result,
the smoothing iron is very efficient with but a comparatively slight expenditure of
generative power. Although this improvement is shown herein as applied to tailors'
irons, it is equally applicable to ordinary flat irons & other forms of smoothing
devices.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1st. In an electrically heated smoothing device a body of magnetic metal
affording the heating and smoothing surface and provided with magnetic studs or
cores in combination with wire coiled about said studs and forming part of an
electric circuit.
2nd. In an electrically heated smoothing device a magnetic metal body affording
the smoothing surface and having studs integral therewith in combination with
metallic conductors surrounding the said studs substantially as and for the purpose
set forth.
3rd. A hollow smoothing iron having studs G and H raised from its bottom in
combination with a handle which is fastened by screws to studs G and electric
heating devices surrounding studs H substantially as set forth.
4th. A hollow smoothing iron consisting of a top plate, a bottom plate or body
and side walls entirely of asbestos, and provided with a handle and internal electric
heating devices, substantially as set forth.
5th. An electric smoothing iron provided with a handle the frame of which
consists of two parts forming between them a guide passage for the wires to the
hollow body of the iron substantially as set forth.
6th. In an electrically heated smoothing device a plate or body provided with
studs or posts in combination with electric conducting material surrounding the said
posts as cores, and bridges fastened to the said posts for holding the said conducting
material in its place substantially as set forth.
7th. In an electrically heated smoothing device a magnetic plate having studs
formed thereon to serve as cores for wire wound in coils or helices substantially as
set forth.
كيمم
GEO.
BARKER,
77, Colmore Row, Birmingham, Agent for Applicant.