IMPROVEMENTS IN THE METHOD OF USING STEAM AND HOT-AIR COMBINED, AND IN THE CONSTRUCTION OF ENGINES IN CONNECTION THEREWITH
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by William Turnbull at the Office of the
Commissioners of Patents on the 19th May 1883.
WILLIAM TURNBULL of N° 2 School Road Villa New Hampton in the County of.
Middlesex." IMPROVEMENTS IN THE METHOD OF USING STEAM AND HOT-AIR
COMBINED, AND IN THE CONSTRUCTION OF ENGINES IN CONNECTION THEREWITH,"
The object of this invention is the construction of an Engine which will be driven
by the combined forces of Steam and Hot air in a manner which will materially
economise the working expenses of such Engine the simplicity of its construction
reduces to a minimum friction of the working parts and loss of heat.
The manner of performing the Invention may be thus described. For example I
employ by preference in the construction of Marine Engines an arrangement of
fixed Cylinders and in order to minimise the space between the Cylinder and the
driving shaft so as to dispense with the connecting rods I mount on the convex
surface of the Cylinder cover a moving or sliding disc maintained in its true
position whilst sliding so as to be steam tight by two radial arms secured to the
Cylinder cover by joints and to a cross head through which the oscillating piston
rod slides. The sliding disc forms a stuffing box on the Cylinder cover through
which the piston rod passes the lower end of the said piston rod inside the
Cylinder being connected by a swivel pin or joint to the piston and its other end
outside the Cylinder is connected direct to the crank of the driving shaft. The
true bearing of the stuffing box disc being maintained on the Cylinder cover by
means of springs placed between the aforesaid crosshead and the stuffing box cover
connected by the radial arms friction and wear between the Cylinder and piston
on that side opposed to the angular thrust of the crank is diminished by the novel
use of Steam or hot air which I cause to be admitted by a suitable duct to that
portion of the frictional surface between the Cylinder and piston which requires it,
the admission to and between such surface being regulated by a ball valve, The
Cylinder I employ both with respect to that portion of the Engine driven by hot
air and that by Steam are high and low pressure Cylinders, the Steam high and
low pressure I arrange in tandum fashion so as to agree with the arrangement of
Cylinders hereafter described driven by hot air and air compressing pumps, for
LD 071

page_text: example, The high and low hot air Cylinders I place side by side connected by
suitable thoroughfares and valves, and above each of these Cylinders I superpose
tandum fashion pumps high and low pressure the pistons or plungers of which are
connected direct with the piston of the hot air Cylinders, the continuous line of
piston rod in each Cylinder from the pump through the piston of the driving
Cylinder being connected direct with the crank and driving shaft., The Steam
Cylinder is arranged in like manner with this exception that the tandum high
pressure Cylinder takes the place and is on a line with the pumps of the hot air
Engine, the low pressure Steam Cylinder being placed below or on a line with the
high and low pressure hot air Cylinders the whole of the said Cylinders by this
arrangement admit of their several and respective piston rods being connected in
manner as before described with the cranks of the driving shafts. Although I
have described as an example high and low pressure Cylinders I would wish it to
be understood that the combined arrangement of driving with Steam and Hot air
can with equal advantage be employed in the construction of ordinary single
Expansion Engines condensing or non-condensing.
In order to maintain and retain an equality of heat in the Cylinders I surround
the same by an outer Cylinder between which and the inner Cylinders an annular
space is formed, into these spaces I admit by suitably arranged ducts and valve,
hot air the heat of which will maintain an equality of heat in the hot air and
Steam Cylinders, or if preferable such annular spaces may be filled in with asbestos
or other nonconducting material. The use of hot air in the annular spaces is a
desideratum as it will offer a means of readily raising temperature at the time of
starting the Engine.
Finally the employment and working of the pumps as described herein in con-
nection with the hot air Cylinders are used as air compressors for forcing air under
pressure into the cooler of the hot air generators described in the Specification of a
Patent granted to me on the 7th May 1873 N° 2301.