An Improved Method of Working a Steam Engine.
Year: 1895

page_text: Date of Application, 7th Nov., 1895
Complete Specification Left, 11th June, 1896-Accepted, 11th July, 1896
PROVISIONAL SPECIFICATION.
An Improved Method of Working a Steam Engine.
I, ALFRED HOGG, of Dunedin, in the Colony of New Zealand Salesman, do
hereby declare the nature of this invention to be as follows:-
:-
Its objects are the utilization of steam power for the working of engines by &
more economical method, and in a more convenient form, than that which now
obtains.
By the reduction of steam pressure in boilers, from the very high temperatures
generally used, to that of atmospheric pressure, or slightly over.
By safety from explosions, which have been increasing in proportion to the
increase of steam pressure used.
By a reduction in the amount of fuel required to produce a given power.
By the reduction of weight and size of steam boilers.
By the increased space available for cargo in steamers, in consequence of the
lesser quantity of fuel required, and the reduction of the weight and size of the
boilers.
Any type of steam boiler may be used, but not necessarily of a greater weight
and strength than sufficient to resist any steam that may be generated slightly.
over atmospheric pressure, to ensure the delivery of water into the cylinder at
about 212 degrees (Fahr.).
As the boiler is merely used for the purpose of heating water, and not for
producing large quantities of steam, it may be of smaller dimensions and of lighter
material.
An ordinary condensing steam engine is used, composed of the usual working
parts, connected to a condenser arranged to keep the cylinder in a constant state
of vacuum.
The quantity of water is regulated to fill the cylinder with active steam (into
which, owing to the absence of atmospheric pressure, it is converted on being
admitted into the cylinder) which forces the piston forward until the pressure is
relieved by the slide valve coming to the position of the return stroke.
Thus, as water at boiling point is well known to be equivalent to atmospheric
pressure, power is exerted on the piston to the extent of the vacuum maintained.
When more cylinders than one are used, they would be connected up as a pair
of engines, and not as compound engines.
In starting the engine, the air in the condenser is displaced by the injection of
steam, and a vacuum is formed by the application of cold water.
For the first few strokes the cold water is applied by subsidiary power; but on
the engine being fairly started, the pump would be worked by the engine in usual
manner.
The boiling water for supplying the cylinder is taken from the hottest part of
the boiler, such as from just over the furnace.
The pipes conveying the water from the boiler to the cylinder, are of smaller
sizes as compared to the pipes now used to convey steam.
Owing to the comparatively low temperature to which the water is heated, a
great saving of fuel is effected, and the danger which now exists from explosions,
is reduced to a minimum.
By the use of vapour in sufficient volume, admitted from the boiler, into the
cylinders at about a temperature of 212 degrees (Fahr.) instead of water; the
I

page_text: same results practically are obtained, but the steam space in the boiler and the steam.
pipes would require to be enlarged as against those required for water.
I am aware that steam has been worked at low pressures, but I am not aware
that anything approaching my method has been in use at any time.
Dated this 30th day of September A.D: 1895.
G. F. Redfern & Co.,
ALFRED HOGG.
4. South Street, Finsbury, London, Agents for the Applicant.
I, ALFRED HOGG, of 31 Moray Place, Dunedin, in the Colony of New Zealand,
Salesman, 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:-
Its objects are the utilization of steam power for the working of engines by a
more economical method, and in a more convenient form, thau that which now
obtains.
By the reduction of steam pressure in boilers, from the very high temperatures
generally used, to that of atmospheric pressure or slightly over.
By safety from explosions, which have been increasing in proportion to the
increase of steam pressure used.
By a reduction in the amount of fuel required to produce a given power.
By the reduction of weight and size of steam boilers.
By the increased space available for cargo in steamers, in consequence of the
lesser quantity of fuel required, and the reduction of the weight and size of the
boilers.
Any type of steam boiler may be used, but not necessarily of a greater weight
and strength than sufficient to resist any steam that may be generated slightly
over atmospheric pressure, to ensure the delivery of water into the cylinder at
about 212 degrees (Fahr.).
As the boiler is merely used for the purpose of heating water, and not for
producing large quantities of steam, it may be of smaller dimensions and of lighter
material.
An ordinary condensing steam engine is used, composed of the usual working
parts connected to a condenser arranged to keep the cylinder in a constant state of
vacuum.
:
The quantity of water is regulated, (preferably by a small slide valve arranged
to shut from the boiler before it opens to the cylinder,) to fill the cylinder with
active steam, (into which, owing to the absence of atmospheric pressure, it is
converted on being admitted into the cylinder) which forces the piston forward
until the pressure is relieved by the slide valve coming to the position of the return
stroke.
Thus, as water at boiling point is well known to be equivalent to atmospheric
pressure, power is exerted on the piston to the extent of the vacuum maintained.
When more cylinders than one are used, they would be connected up as a pair
of engines, and not as compound engines.
.
In starting the engine, the air in the condenser is displaced by the injection of
steam, and a vacuum is formed by the application of cold water.
For the first few strokes the cold water is applied by subsidiary power; but on
the engine being fairly started, the pump would be worked by the engine in the
usual inanner.

page_text: The boiling water for supplying the cylinder is taken from the hottest part of
the boiler, such as from just over the furnace.
The pipes conveying the water from the boiler to the cylinder are of smaller-
sizes as compared to the pipes now used to convey steam.
Owing to the comparatively low temperature to which the water is heated, a.
great saving of fuel is effected, and the danger which now exists from explosions, is.
reduced to a minimum.
By the use of vapour in sufficient volume, admitted from the boiler into the
cylinder at about a temperature of 212 degrees (Fahr.) instead of water, the same-
results practically are obtained but the steam space in the boiler and the steam
pipes would require to be enlarged as against those required for water.
I am aware that steam has been used at low pressures, with and without.
condensers, and I am also aware that water has been used at high pressures, stored
in secondary receivers, but I am not aware that anything approaching my method
has been in use at any time, commercially.
I do not rely on the use of water at a high temperature nor steam at high.
pressure, nor do I use compound engines but a simple engine, or if more than one-
cylinder, then connected as pairs; the pressure I use is that produced by hot.
water spray, or vapour, delivered into the cylinder at about (212 degrees Fahr.).
atmospheric pressure being withdrawn by the action of the condenser and
air-pump.
A continuous supply of hot water or vapour is produced by any type of boiler-
heated by a furnace in the usual manner; I use low pressure engines as at present
constructed, only adding a means of regulating the inflow of the hot water, as-
alluded to in my Provisional Specification and described herein namely a small.
regulating valve, and even this is not required if vapour be used instead of water.
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 [
claim is
1. An improved method of working a steam engine by water taken from the
hottest part of a boiler, through small pipes and admitted by slide valves, preferably
in the form of spray, direct into the cylinder or cylinders of a condensing engine,.
at a temperature of about 212 degrees (Fahr.). In the absence of atmospheric
pressure the water expanding into steam and exerting a pressure on the piston in
proportion to the vacuum maintained in the condenser, substantially as and for the
purposes described and explained herein.
2. An improved method of working a steam engine by vapour taken from a..
boiler through steam pipes and admitted by slide valves direct into the cylinder or
cylinders of a condensing engine at a temperature of about 212 degrees (Fahr.).
In the absence of atmospheric pressure the vapour exerting a pressure on the-
piston, in proportion to the vacuum maintained in the condenser substantially, as-
and for the purposes described and explained herein.
3. An improved method of working a steam engine by connecting up more
cylinders than one as pairs; all cylinders being fed by vapour or water spray, at
a temperature of about 212 degrees (Fahr.) direct from the boiler, and all the
cylinders being connected direct with the condenser; each cylinder being fitted.
with a small regulating valve when water spray is used, substantially as and for-
the purposes described and explained herein.
נ.ינד
1100A
ALFRED HOGG.
G. F. Redfern & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.