Year: 1888

page_text: Date of Application, 25th June, 1888
Complete Specification Left, 18th Mar., 1889
Complete Specification Accepted, 20th Apr., 1889
RESERVE
I, JOHN TREWHELLA of 4 Station Terrace New "Dock Llanelly in the County of
Carmarthen, Engineer do hereby declare the nature of. this invention to be as
follows:-
This Invention relates to improvements in Hot Air Engines.
In carrying out my Invention I construct a Casing preferably circular, but which
may be made in any other form, of Cast Iron or any other suitable metal, in one or
any number of pieces. I prefer to make it in halves.
This Casing I place over or at side and attach same to an heating Furnace.
Fixed to the opposite side of the Furnace upon this Casing 1 construct a Water
tank.
The purposes of this Casing are to provide Hot and Cold Walls or plates in opposite
Hemispheres.
Inside of this casing, I place a Drum constructed with suitable air chambers and
passages, and made in one or any number of pieces fixed to and revolving with the
Main Shaft of Engine. The purposes of this Drum are to convey the Heated Air
from the Hot Walls of the outer casing to the cylinder and for removing same air
from the cylinder when expended.to the Cold Walls or plates of the outer casing
alternatly with each revolution.
The working cylinder I fix as. near the outer casing as convenient, and may be
placed Horizontally or Vertically-I prefer it Vertical and Mount upon suitable
foundation plate with Standards, and connect the Piston in the usual way by means of
Connecting Rods to crank shaft.

page_text: JOHN TREWHELLA of No. 10 Cornish Place, New Dock, Llanelly, in the County
of Carmarthen Engineer 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:—
This Invention, relates to Hot Air Engines, in which the heated air is conveyed,
from the hot walls of an heated Furnace, to a Cylinder, fitted with a working Piston,
and when its force is expended, is afterwards conveyed, to the Cold Walls of a Water
Tank, by means of a revolving Drum, constructed with suitable air chambers and
passages for that purpose, instead of by a plunger, or Piston, displacer, as is usually
done.
In order that my Invention may be easily understood, and readily carried into
effect, I will proceed to explain, by the aid of the accompanying Drawings, reference
being made to letters thereon.
Fig. 1 is a Side Elevation sectionally drawn.
Fig. 2 is a front Elevation, also in section.
A being the internal revolving Drum. B an Air Space or Chamber, in same,
C are passages, leading from same to Cylinder E. D being the heating furnace,
F is the outer casing, attached at one side to the Heating Furnace D, the opposite
side being attached to a Water Tank I. I prefer to place the heating Furnace
underneath, and the Water Tank above, the Casing, but if desired, these may be
placed at opposite sides, K. K. K. are therefore the Hot Walls, H. H. H. are
Cold Walls, L is the Piston, working in Cylinder E. M. is the Piston Rod Guide,
N is the Drum Shaft, which may also be used as the Crank Shaft for Engine, O. being
the Crank Pin, P. is the chimney from Heating Furnace.
Motion is obtained in the following way. After the furnace has been sufficiently
heated, and water placed in the Water Tank, the air space or chamber B, is brought
in proximity with the Hot Walls K, the air at once becomes expanded, and rushes up
passages C, and propels the piston to the end of its stroke, at which time, the air
space in Drum, will have traveled, and be then in contact with the Cold Walls H,
when Condensation, and Vacuum, instantly occur, which draws the Piston in its
downward stroke, this process, is repeated every revolution, in the case of where the
Drum, with one air space, is fixed on to crank shaft, as shown in Figs. 1, and 2,
and which construction I much prefer, or it may be repeated more than once, in
every revolution of Drum, by fixing the Drum, on a separate shaft, and geared to
Engine shaft, in which, in which case, air spaces would be constructed in Drum,
in proportion of one space, to each revolution of crank shaft, if such were desired.

page_text: 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,
An internal Drum with air spaces, and passages, constructed in same, revolving
inside an Outer casing, provided with Hot and Cold Walls, substantially as described,
and for the purposes set forth.
In witness whereof, 1 the said John Trewhella, have hereunto set my hand and
seal, this Ninth day of March, in the year of our Lord, One thousand eight
hundred and eighty nine.