improvements in Gas and other Engines.
Year: 1887

page_text: Date of Application, 15th Nov., 1887
Complete Specification Left, 15th Aug., 1888
Complete Specification Accepted, 21st Sept., 1888
improvements in Gas and other Engines.
I CHARLES DAVY, of 30 Whitworth Road, Ranmoor, Sheffield in the County of
York, Engineer do hereby declare the nature of this invention to he as
follows:-
My Invention has for its object to diminish the consumption of gas in gas engines
by maintaining a higher temperature in the jacket surrounding the working cylinder
and combustion chamber, and consequently in the walls of the working cylinder and
combustion chamber than is possible when water is used as the cooling agent in the
jacket, avoiding at the same time the danger of overheating which might ensue were
no cooling jacket employed. The Invention may be applied to any engine worked
by explosive gas or vapor.
If water be employed as the cooling agent the highest temperature practically
maintainable in the jacket is necessarily lower than the boiling point of that liquid and
hence an excessive amount of heat is abstracted from the working cylinder and com-
bustion chamber which entails a correspondingly wasteful consumption of gas.
My Invention consists in a mode of maintaining a much higher (mean) temperature
in the jacket and consequently in the walls of the working cylinder and combustion
chamber by the employment as the cooling agent, of a fixed oil the boiling point of
which is much higher than that of water at atmospheric pressure.
In carrying out the invention, it is desirable to provide against the oxidation of the
oil which would occur and the objectionable odor which would be given off if the hot
oil were exposed to the atmosphere; and to this end it is necessary that the oil should
circulate in a closed system whereby the oil will be sufficiently cooled to prevent the
temperature in the jacket rising beyond the desired limit, the circulating system being
provided with means of accommodating the variable expansion of the oil.
The jacket would be connected with a suitable cooling reservoir by flow and
return pipes. This reservoir may be in the form of a tank which may or may not be
traversed by, or combined with, a system of tubes or may be composed wholly of tubes
or coils or be otherwise so constructed as to expose a sufficient area of cooling surface.
077

page_text: The reservoir would be closed to prevent access of air to the hot oil and would be
provided with a means of accommodating the expansion of the heated oil such for
instance as an open pipe carried to a sufficient height or a supplementary reservoir
open to the atmosphere and situated at a higher level than the main reservoir and in
free communication therewith by a siphon tube so that whilst expansion of the heated
oil is permitted there will be no circulation of oil between the closed and the open
reservoirs and the oil in the latter which is exposed to the air will not be heated. The
supplementary tank may however be closed and contain air against which the oil would
cushion, or it may be covered by a bell chamber with hydraulic seal or by a loaded
plunger resting on the surface of the oil. Or, the coil reservoir may be sufficiently
expansible in itself to accommodate the oil.
Fil
Nawambon 1887
C. DAVY.
By A. M. & Wm. Clark,
53, Chancery Lane, London,
Patent Agents.

page_text: Improvements in Gas and other Engines.
I CHARLES DAVY of 30 Whitworth Road, Ranmoor, Sheffield in the County of
York, 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 :-
My invention has for its object to diminish the consumption of explosive gas or
vapor in gas and other engines by maintaining a higher temperature in the jacket
surrounding the working cylinder and combustion chamber-and consequently in the
walls of the said cylinder and chamber-than is possible when water is used as the
cooling agent in the jacket, avoiding at the same time the danger of overheating which
might ensue were no cooling jacket employed. The highest temperature practically
maintainable in the jacket is necessarily lower than the boiling point of the liquid
employed therein and hence it follows that if water be so employed, an excessive amount
of heat is abstracted from the working cylinder and combustion chamber which entails
a correspondingly wasteful consumption of gas.
My invention consists in a mode of maintaining a much higher (mean) temperature
in the jacket and consequently in the walls of the working cylinder and combustion
chamber, by the employment, as the cooling agent, of a fixed oil such as olive oil,
the boiling point of which is much higher than that of water at atmospheric
pressure.
In carrying out the invention it is desirable to provide against the oxidation of the
oil which would occur, and the objectionable odor which would be given off if the hot
oil were exposed to the atmosphere, and to this end it is necessary that the hot oil
should circulate in a closed, or practically closed, system in such a manner that the oil
will be sufficiently cooled to prevent the temperature in the jacket rising beyond the
desired limit (i.e. beyond the boiling point of the oil, or beyond such a temperature
that the piston and rings would become overheated, whichever temperature is the
lowest); the circulating system being provided with means of accommodating the
variable expansion of the oil without exposing the hot oil to the air.
Reference is to be had to the accompanying drawings forming part of this specifi-
cation wherein I have represented various ways of carrying my invention into effect.
Figure 1 is a typical example of the entire arrangement, and the other figures show
various ways of circulating and cooling the oil and providing for its expansion
when heated.
letters of reference serve for like parts in all the
The same
figures.
In Figure 1, A is a cross section of the working cylinder or combustion chamber,
and B is the jacket surrounding the same. It is constructed in the ordinary manner
and connected with a suitable cooling reservoir by flow and return pipes CD con-
nected respectively with the top and bottom of the jacket B. In the example shown
in Figure 1, this reservoir is in the form of a closed tank E presenting sufficient
surface area to the surrounding air. This tank is filled with oil, and to provide for its

page_text: expansion an inverted syphon tube F is connected with the upper part of the tank E
and with an open tank G at or above the level of the top of the tank E. By this
means free expansion of the oil in the closed tank E is permitted, but by the use of
the inverted syphon tube F, the oil in the tank G which is exposed to the atmosphere.
cannot become heated by convection. Instead of the open tank and syphon tube, I
may simply connect an open tube to the tank and carry it to such a height that the
heated oil rising therein by convection will be sufficiently cooled before it reaches the
surface where it is exposed to the air.
In order that the reservoir E may have sufficient cooling surface, it may be
traversed by a system of tubes H, as in Figure 2, or coils, through which air may be
allowed to circulate. Or the reservoir may be combined with such cooling tubes, or
it may be constructed partially or wholly of tubes or coils through which the heated
oil is caused to circulate as in Figure 3, or it may be otherwise so constructed to
present a sufficient area of cooling surface.
Instead of the supplementary tank G being open and the cool stratum of oil therein
being under atmospheric pressure, it may be closed as in Figure 4 and contain air
against which the oil would cushion. Or it may be covered by a bell chamber with
hydraulic seal. Or the said tank G may be a cylinder and contain a loaded piston or
plunger which rests on the surface of the oil and so protects it from contact with the
atmosphere.
Or the reservoir E may be sufficiently expansible in itself to accommodate the oil,
for instance if made in the form of tubes, the tubes may be of thin metal and of oval
section so as to easily expand and approximate to a circular section under
internal pressure. Or, if made in the form of a tank, the shell may be constructed
of thin, corrugated sheet metal as in Figure 5 the corrugations extending longi-
tudinally or circumferentially.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is.
L
1st. The herein described method of maintaining comparatively high mean
temperature in the jacket of the working cylinder and combustion chamber of an
engine worked by explosive gas or vapor whilst yet preventing overheating, which
method consists in the employment in said jacket of a fixed oil in combination with a
circulation system whereby the temperature of the oil is prevented from rising beyond
a given limit, and with means whereby the exposure of the hot oil to the air is
prevented, substantially as herein specified.
2nd. The combination with the jacket of an engine worked by explosive gas or
vapor, of a practically closed circulation system of pipes and reservoir so as to maintain a
circulation of liquid through the jacket and cool the liquid whilst permitting its free
expansion without exposing the hot liquid to the air, substantially as herein
specified.
Doted this 15th dove of du
1724