Improvements in Electric Heating Devices and Contacts for the same.
Year: 1892

page_text: Date of Application, 29th June, 1892
Complete Specification Left, 26th Apr., 1893-Accepted, 27th May, 1893
PROVISIONAL SPECIFICATION.
Improvements in Electric Heating Devices and Contacts for
the same.
I FRIEDRICH WILHELM SCHINDLER-TENNY, Gentleman, Kennelbach near
Bregenz in Austria do hereby declare the nature of this invention to be as
follows:-
My invention relates to electric cooking and heating devices in general, and in
particular to the electric heating and cooking apparatus described in my Patent
No. 16767 of October 2nd 1891, and has for its object the construction of improved
means for the level adjustment of electric heaters, for preventing their covers from
warping, and for protecting the heating body from moisture, and also of contact
devices to be used for these apparatus.
The heating body proper, which may, as described in my above mentioned
Patent, consist of a plate of insulating refractory material provided on its surface
with grooves for the reception of the electric conductor (platina wire) and covered
with a thin sheet of insulating refractory material (mica), is placed in a metal
frame composed of two annular walls or webs and of a bottom by which said walls
are tightly joined and form a hollow ring into the centre of which the heating
body fits, so as to be surrounded by the hollow annular space of said frame. On
the lower side of the annular frame supports are provided, carrying vertical
adjusting screws upon which rests the heating body so that by adjusting of said
screws it may be set into a perfectly level position. The metal cover for the
heating body is on its lower side centrally provided with a pin which is passed
through a central hole in the mica sheet covering the heating body and in the latter
itself. The pin attached to the metal cover and passing through the heating body
is on its free end underneath the latter provided with two or more lugs which
engage upon two inclined surfaces on the under side of the supports with which the
annular frame is provided, in such manner that, by giving to the metal cover and
its pin a turn or a half turn, the cover and annular frame, between the two of
which the heating body is situated, will be drawn tightly together. The cover is
by preference provided with an annular rim or flange which fits behind the inner
wall or ring of the annular frame.
The whole body thus formed is placed in a corresponding opening in a range-
plate, into a circular recess of which opening the plate of the heating body is made
to fit tightly. The joint thus formed is situated above the annular space of the
heater ring or frame so that if any liquid, getting on the plate in cooking, should
happen to leak through said joint, it cannot reach the heating body, which might
crack in consequence, but will run into the said annular space, whence it may be
let off by a tap or where it will evaporate.
The contact-device used in combination with electric heating and cooking
apparatus of this kind, which serves for connecting such apparatus with the main
line are constructed as follows. Two pieces of metal are let into an insulating
body, such as for instance an ebonite or wooden knob, and provided with two
contact screws for connection with the wires of the line. These two pieces of
metal are provided with a conical hole each, while two similar pieces of metal,
similarly connected with other wires, and also let in or set in an insulating body,
are provided, with conical pins to fit the holes in the other contact piece just
described. The other ends of the latter wires may be connected direct or by
means of similar contact devices with the electric cooking or other apparatus.
When these apparatus are to be connected with the line the knob or body

page_text: provided with the contact pins is pushed into the holes of the contact piece of the
line and the connection will be established.
Dated 29th June 1892.
GEO.
DOWNING,
8, Quality Court, London, W.C., Agent.
COMPLETE SPECIFICATION.
Improvements in Electric Heating Devices and Contacts for
the same.
I, FRIEDRICH WILHELM SCHINDLER-JENNY, of Kennelbach near Bregenz,
Austria, Manufacturer, do hereby declare the nature of this invention and in what
manner the same is to be performed to be particularly described and ascertained in
and by the following statement :-
My invention relates to electric cooking and heating devices in general, and in
particular to the electric heating and cooking apparatus described in my Patent
No. 16767 of October 2nd 1891, and has for its object the construction of improved
means for the level adjustment of electric heaters, for preventing their covers from
warping, and for protecting the heating body from moisture, and also of contact
devices to be used for these apparatus.
In the annexed drawing a construction of this kind is shown, of which:
Fig. 1 represents an electric heater in top-view.
Fig. 2 shows a vertical section through the same and through the range-plate.
Fig. 3 is a bottom-view of the heater.
Fig. 4 is a perspective-view of a range-plate with heater and contact-device
attached thereto.
Fig. 5 represents a contact-device proper.
Figs. 6 illustrate the one part of the contact-device in bottom-view, side-view
(partly in section) and cross-section.
Figs. 7 represent the other part of that connection in top-side- and front-view.
Figs. 8 represent a modification of the construction shown in Figs. 6, in elevation
and sectional view, the cover being removed.
The heating body proper, which may, as described in my above mentioned
Patent, consist of a plate of insulating refractory material, provided on its
surface with grooves c for the reception of the electric conductor (platina-wire)
and covered with a thin sheet d of insulating refractory material (mica), is placed
in a metal frame A composed of two annular walls A and A2 and of a bottom
by which said walls are tightly joined and form a hollow ring B, into the centre of
which the heating-body 6 fits so as to be surrounded by the hollow annular space B
of said frame. On the lower side of the annular frame A supports or arms C
are provided, carrying vertical adjusting screws D D D... fitted with the annular
plates d d d.. .., upon which the heating body brests, so that by adjusting the
said screws it may be set into a perfectly level position. In order to prevent a
displacing of the heating-body b the points or ends of the screws D may engage
into corresponding recesses or openings on the lower side of the refractory
plate b.
The latter as well as the covering mica-sheet and the bottom of the frame A,
i.e. the arms or supports C, are provided with a central opening.
The metal cover a for the heating body is provided with an annular flange a
being of a smaller diameter, said flange fitting behind the inner wall or ring A¹ of
the annular frame. The cover a is on its lower side centrally provided with a
pin a passing through a central hole in the mica sheet covering the heating body
and in the latter itself.
The pin a' is, on its free end, provided with two or more lugs ff, for the passage
of which the central opening of the frame A i.e. of the arms CC, is provided

page_text: with corresponding recesses ff, whereas the central opening in the mica-plate
and in the heating-body is sufficiently large enough to let pass the pin with its
lugs. The under-side of the support is provided with 2 corresponding inclined
surfaces I 9, in such a manner that, by giving to the metal cover a and its pin a
a turn or half a turn, the cover a and annular frame A between the two of which
the heating body is situated, be drawn tightly together.
In order to be enabled to turn the cover a, the latter is provided with 2 holes
or openings into which may be fitted a key J, as may be seen in the drawing.
That central connection of the cover a permits, when heated, its free dilatation in
every direction. The cover a fits into a corresponding recess in the range-plate h,
which latter is provided with a flange h upon which rests the cover.
By the internal ring A in combination with overlapping flange al the heating
body is perfectly protected against the entering of any liquid, that should happen
to leak through said joint, the liquid cannot reach the heating-body, which might
crack in consequence, but will run into said annular space, whence it may be let
off by a tap or where it will evaporate.
In order to limit the entering of liquid even into this space, a packing e, prefer-
ably of asbestos, may be laid between range-plate & cover, in which case a tap or
valve may be dispensed of.
Such heating apparatus may be provided in any suitable number in a range-
plate.
The contact-device used in combination with electric heating and cooking
apparatus of this kind, which serves for connecting such apparatus with the main
line are constructed as follows:
Two pieces of metal are let into an insulating body k, such as for instance
an ebonite or wooden knob, and provided with two contact screws m m for con-
nection with the wires of the line. These two pieces of metal are provided with
a conical hole or tube an each, while two similar pieces of metal, similarly
connected with other wires, and also let in or set in an insulating body, are
provided with conical pins oo to fit into the holes or tubes n n in the other
contact piece just described. The one of the 2 connecting-devices, preferably
that with the holes or tubes n n is intercalated in the main circuit, and may be
covered by a cap (see Fig. 6) and is attached to a suitable place on the wall. The
wire of the secondary circuit, being provided on its end with the connecting-device
carrying the pins oo may be connected permanently either to the object to be
treated electrically or it may be used the other connecting-device described above;
it is of no importance whether the object be provided with pins and the connecting-
device with holes or vice-versa.
Fig. 8 represents a modification of the connecting-device, but only in respect to
the form, so that a detailed Specification is not necessary.
Having now described the nature of my invention, I claim:
1.) In an electric cooking and heating device a frame A with ring A' and
setting-screws D D D (preferably with discs or plates d), engaging the
refractory insulating-plate b, in order to enable the level adjustment of that plate b;
as set forth.
2.) In a heating-device, claimed in 1) a cover a, provided with flange a¹ and
central pin a², passing through the whole heating-body and being provided with
inclined surfaces to enable a tightening of the connection; as set forth.
3.) In a heating-device, claimed in Claim 1) an inner ring A' and an external
ring A, forming together with the bottom an annular space A for the reception
of eventually dropping down liquids; as set forth.
4.) In a heating-apparatus, described in Claim 1) a packing e, preferably of
asbestos, between the cover and a flange of the range-plate, upon which the
cover a rests; as set forth.
5.) In an electrical heating-device a connecting-device, consisting of the insulated

page_text: metal strips
with connection screws for the conducting-wire being provided on
the one side with holes or tubes n n and on the other side with metal pins o o
fitting into said holes; especially as described.
Dated 26th &il 1902
GEO.
DOWNING,
8, Quality Court, London, W.C., Agent.