Improvement in or connected with Heating or Cooking Vessels, and Apparatus to be used in the Manufacture of the same.
Year: 1889

page_text: Date of Application, 27th May, 1889
Complete Specification Left, 27th Feb., 1890-Accepted, 29th Mar., 1890
PROVISIONAL SPECIFICATION.
Improvement in or connected with Heating or Cooking Vessels, and
Apparatus to be used in the Manufacture of the same.
I, ERNST OBERWINTER, Manufacturer, of Lippstadt, Germany, do hereby declare
the nature of this invention to be as follows:-
My invention has for its object to protect earthenware vessels from destruction by
the direct action of flames. For this purpose, I arm the bottom of such vessels with
sheet metal in such a manner, that it does not touch the bottom with its entire face,
but only along the circumference or at certain points, so as to allow the access of air
between the earthenware and the meta!. The said metal base may have the shape of
a disc or circular plate or frame, provided with perforations, ribs, corrugations or
grooves of any convenient shape; and with a circular rim or flange which surrounds
and holds the bottom of the vessel.
For fixing the said metal base without danger of breaking the vessel, I apply to
the inside of the vessel an elastic support which serves as an abutment, while the
metal base is put on.
The said elastic support is preferably formed by four round pieces or pads of india-
rubber, arranged in a circle, and fixed to an expansible lever mechanism operated by
means of a screw spindle.
This lever mechanism comprises a system of angle-levers, pivoted to a central
block, each lever carrying at one end one of the said india-rubber pads, while the
other and shorter arm is connected with a central sleeve by means of a link. The
said sleeve is fixed by set-screws to the projecting end of a hollow shaft which is held
in a pair of bearings, and serves as a nut for a long screw-spindle. One end of the
latter is held in the central block or pivot carrier mentioned above, and serves to
press the latter forward, so as to expand the system of leverage, while the other end
of the spindle carries a hand-wheel.
Dated thin 95th dow of May 1889
FAIRFAX & WETTER,
433, Strand, London, Agents.
COMPLETE SPECIFICATION.
Improvement in or connected with Heating or Cooking Vessels, and
Apparatus to be used in the Manufacture of the same.
I, ERNST OBERWINTER, Manufacturer, of Lippstadt, Germany, 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 has for its object to protect earthenware vessels from destruction by
the direct action of flames. For this purpose I arm the bottom of such vessels with
sheet metal in such a manner, that it does not touch the bottom with its entire face,
but only along the circumference or at certain points, so as to allow the access of air
between the earthenware and the metal. The said metal base have the shape of
may
a disc or circular plate or frame, provided with perforations, ribs, corrugations or
grooves of any convenient shape; and with a circular rim or flange which surrounds
and holds the bottom of the vessel.
The accompanying drawings show various protecting plates or discs and the
manner of applying them to earthenware vessels.
Fig. 1, is a vertical section and Fig. 3 a plan of a vessel with concave bottom,

page_text: .
armed with a metallic plate. This plate has a circular flange, a number of perfora-
tions fand a circular corrugation g. In the modified form represented by 2, the
annular corrugation g is omitted.
Fig. 4 represents a flat protecting plate without holes, Fig. 5 one with holes, Fig. 6
shows a plate with zig-zag-shaped grooves or inverted corrugations without holes, and
Fig. 7 the same with holes.
In Figs. 8 and 9 the grooves or corrugations are star-shaped.
Figs. 10 and 11 show protecting discs with concentric circular grooves.
In Figs. 12 and 13 a single groove or ridge is arranged in zig-zag shape, Figs. 14
and 15 represent plates having concentric grooves or ridges arranged in concentric
circles and connected with each other radially.
In Figs. 16 and 17 the ridges or grooves are parallel. In Figs. 18 and 19 there
are two sets of parallel ridges or grooves crossing each other at right angles.
A metallic disc as described serves not only to prevent the vessel from cracking,
but also to avoid the superficial charring of the food or other organic matter
contained in the vessel.
For fixing the said metal base without injury to the vessel it is necessary, to adopt
special precautions or to use special apparatus, for instance the apparatus represented
by Figs. 20 to 27 of the drawings.
Care should be taken, while fixing the bottom, that the vessel is not exposed to
hard (rigid or inelastic) pressure from two sides.
My special apparatus, which is illustrated by Figs. 20 to 25 of the accompanying
drawings, serves to hold the vessel from the inside and to form an elastic or com-
pressible support for the bottom edge, while the metal bottom is put on. This
apparatus or holder is constructed as follows:-
On a hollow spindle (Fig. 20) is mounted a longitudinally adjustable sleeve A,
which is connected by a pair of links with a pair of bell-crank levers ab pivoted to
a conical cap E. The latter is secured to the front end of a screw spindle D,
surrounded by the hollow spindle B. The free end of each arm 6 carries a round
piece B of india-rubber, which should be rather hard, but elastic. Instead of india-
rubber, other suitable compressible material may be employed.
A vessel having been placed on the holder, so that the india-rubber pieces G are in
the interior of the vessel, the adjustable spindle D, together with the cap E is screwed.
forward and thereby the arms b, b caused to expand, so as to press the india-rubber
pads into the corner of the vessel. These pads now form an adjustable support or
rest which holds the vessel, while the metallic plate F is being fixed to the bottom of
the vessel by bending up the edges in the manner shown by Fig. 20. Figs. 26
and 27 represent the plate F before it is flanged. To prevent the holder from
receding during the operation, while allowing it to turn on its axis, I employ set
screws d and h and a screw-nut h. Fig. 21 shows the holder, partly in end view,
partly in cross section; Fig. 23 is an end view of the cap E; Fig. 24 is a section
along line S-S of Fig. 20, and Fig. 25 a side view of the sleeve A.
Fig. 22 shows the application of the same holder to a smaller vessel, than that
shown in Fig. 20.
As cooking, vessels have rarely a great depth, the shaft on which the holder is
mounted may project a considerable distance over its bearing.
Under the name earthenware I wish to include all varieties, such as common
earthenware, porcelain and faience. Instead of separate india-rubber pads G, I may
employ a continuous rubber-ring.
Having now particularly described my invention and in what manner the same is
to be performed, I declare I claim :-
1. Earthenware vessels, armed with a metallic bottom of such a shape, as to admit
air between the metal and the vessel, substantially as described and for the purposes
specified.

page_text: 2. The combination of an earthenware vessel, with a protecting bottom plate of
sheet metal secured to the vessel by a turned-up flange and provided with holes,
corrugations, ridges or grooves, substantially as described and for the purposes
specified.
3. The method or means for supporting and holding earthenware vessels during
the application of a metallic bottom plate, substantially as described.
4. Apparatus for holding earthenware vessels during the application of metallic
bottom plates, comprising in its construction a set of levers 6 carrying india-rubber
pads G and connected with an adjustable sleeve A mounted on a shaft B, and a
movable spindle D, with cap E adapted to drive the said levers apart, so as to press
the pads G against the inner bottom edge of the vessel, substantially as described.
1800
ERNST
OBERWINTER.
By Fairfax & Wetter,
433, Strand, London, Agents.