Year: 1897

page_text: FRANCIS WILLIAM GREENGRASS, Engineer, Church Street, Epsom, Surrey, do
hereby declare the nature of this invention to be as follows:-
The object of this invention is to provide a cooking vessel whereby the cooking
of such food stuffs as require constant stirring or agitating may be brought about
automatically and independently of the attention of the cook.
Especially is the principle applicable to porridge gruel & the like (although
in no ways limited to these) which same in cooking demand a constant attention
and tedious stirring.
A vessel made in accordance to my invention provides the necessary agitation
for the breaking up and seperating of the particles, and can be left entirely without
attention, and perform the proper cooking better and more expediously. I now
describe my invention and the manner of producing the agitation necessary.
A suitable vessel is taken of any external form (as an ordinary saucepan) within
the same is fitted a lining in such a manner as to slope inwards, reducing the size at
the bottom to somewhat of the form of an inverted cone, the said lining being
secured to the outer vessel in such a manner to be steam tight.
The arrangment may be rolled from one piece if preferred.
To the outer vessel is fitted a plug for filling and sealing the same.
A pipe or conduit is led from the lower and central point of the inverted cone
shaped lining, and is carried up between the said lining and the outer vessel and
finishes with its open end at the higest point obtainable in the space between;
the space forms a water jacket to the lining.
At the bottom of the inner lining is fitted a removable perforated plate the object
of which is to prevent the ingredients passing down and choking the said pipe or
conduit.
The whole manner of construction is such, that the outer and inner vessels are
seperate holders, but are joined from the highest point of the outer to the lowest
point of the inner by a pipe, pipes, or conduit.
The manner of working is such that upon the outer vessel being supplied with
water and sealed by the plug, upon the water boiling, there being no way of escape
for the steam but through the descending pipe or conduit, the said steam is led
under slight pressure to the bottom of the inner holder, bringing it rapidly to the
boil and the condensation giving rise to considerable agitation of the contents.
Upon the boiling temperature being attained the steam escapes directly upwards
through the contents of the inner vessel throwing up the particles in a fountain like
form, which falling again upon the sloping sides, gradually work down, until
meeting the issueing steam the process is repeated, giving a continual circulation
& seperation of the particles.
Dated this Seventh day of December 1897.

page_text: I, FRANCIS WILLIAM GREENGRASS, Engineer, Church Street, Epsom, Surrey, 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:--
The object of the present invention is to provide a cooking vessel whereby
porridge, gruel and such liquid food stuffs as require constant stirring and
agitation during the cooking process may be properly prepared without necessitat-
ing the attention of the cook.
By means of my invention, the requisite agitation of the entire contents of the
cooking vessel is automatically effected throughout the cooking process as will
hereinafter appear.
According to my invention, my improved cooking vessel comprises an inner
vessel contained within or surrounded by an outer vessel which forms a steam tight
water jacket. The bottom of the inner vessel slopes downwards towards the centre
presenting the form or approximate form of an inverted cone, and a steam pipe
or passage leads from the steam space of the outer vessel to the lowest point of
the bottom of the inner vessel, thus when the water in the outer vessel reaches
boiling point steam at slight pressure enters at the lowest point of the inner vessel
bringing its contents rapidly to the boil, the condensation of the steam at the
same time causing considerable agitation of such contents.
So soon as such contents attain boiling point the steam escapes upwards through
them throwing up particles in a fountain like form which fall again into the vessel
near the sides, fresh particles constantly descending the sloping bottom to the
lowest point thereof where the steam is admitted and being in turn thrown up, a
continual separation and circulation of the entire contents being thus automatically
effected. From the abovo it will appear, and I wish it to be clearly understood,
that it is absolutely essential and a feature of my invention that the bottom of
the inner vessel should slope downwards towards a central point and that the steam
should enter the inner vessel at, or approximately at, this point.
In the accompanying drawings in which similar letters refer to like parts in
both figures:-
-
Fig. 1 is a sectional elevation of a cooking vessel or saucepan constructed in
accordance with my invention and Fig. 2 is a like view of a slightly modified
arrangement.
a is the inner vessel or container the bottom b of which slopes downwards towards
the centre where the small orifice c is formed. d is the onter vessel or steam
tight water jacket which is filled through the pipe e closed by a steam tight cap f.
This pipe e should not exceed in height the desired level of the water in the
jacket, say one inch from the top, thus preventing overfilling. From the steam
space of the outer vessel or jacket & the steam pipe or passage g lends to the before
mentioned orifice at the lowest point of the inner vessel a.
In order to prevent any of the contents of the inner vessel from being sucked into
the steam pipe, as might occur, were the vessel removed from the fire, owing to
the partial vacuum then formed in the outer vessel or jacket d, I provide the steam
space of the latter with an air inlet aperture h normally maintained closed by a s
small valve carried by a spring secured to the side of the jacket. Should a
partial vacuum be formed in the jacket d it will at once be destroyed, the valve i
opening inwards immediately to the pressure of the external air.
In the modification, Fig. 2, the steam pipe g in lieu of passing down the exterior

page_text: of the inner vessel passes down the interior thereof to its lowest point, being pre-
ferably serrated around its outlet to facilitate the escape of the steam. A detach-
able joint of any convenient construction is preferably made in the pipo y as at gl
and this arrangement permits the use of a removable earthenware or like lining
within the inner vessel the bottom of said lining being of course inade to slope
downwards towards a central point. On disconnecting the steam pipe at g' the
lining can readily be removed. m is a convenient lid or cover to the cooking
vessel.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:
1. A cooking vessel, comprising an inner vessel and a surrounding outer vessel
or steam tight water jacket, wherein the automatic agitation of the whole of the
liquid contents during the cooking process is effected by making the bottom of the
said inner vessel slope downwards towards a central point and leading a steam
pipe or passage from the steam space of the outer vessed to the centre of the bottom
of the inner vessel so that a jet of steam under slight pressure enters the latter at
its lowest point, substantially as described.
2. A cooking vessel for the purpose set forth constructed and arranged sub-
stantially as described and illustrated in the accompanying drawings.
Dated this 11th day of July 1
E. P. ALEXANDER & SON,
Chartered Patent Agents,
19, Southampton Buildings, Chancery Lane, London, W.C., Agents.