Improvements for Preventing the Overheating of Revolving Shafts, and for Cooling the same if Overheated.
Year: 1896

page_text: Date of Application, 4th May, 1896
Complete Specification Left, 4th Feb., 1897-Accepted, 4th May 1997
PROVISIONAL SPECIFT
Improvements for Preventing the Overheating of Revolving Shafts,
and for Cooling the same if Overheated.
I MORTIMER EVANS of the Savile Club Piccadilly Civil Engineer do hereby
declare the nature of this invention to be as follows:-
It is well known that shafting running at a high speed or under much pressure
often heats to an inconvenient or even dangerous extent and that this is so
especially when the lubrication has from any cause become defective. The object
of this invention is to prevent this overheating or the reduction of such heat if
generated.
For this purpose 1 apply the cold derived from the expansion of a highly
compressed gas or gasses and preferably allow such gas or gasses to do work in
expanding that a very low temperature may be obtained. In some cases I employ
the expansion of such gas or gasses in conjunction with the evaporation of a
suitable liquid or liquids such as alchohol or ether and in others either alone with
the expanding gas or with both gas and liquid I take advantage of the cold
produced by the liquifaction of a deliquesant salt or salts any or all of which I use
singly or together as may be most suitable.
I also take advantage of the pressure of such gas or gasses to assist the
lubrication of such shafting to be cooled and to effect this I force the lubricant by
the pressure of the gas through and about the rubbing surfaces as desired.
I preferably allow the gas or gasses to expand inside or about the journal
bearings and when the shafting is hollow I sometimes avail myself of this
bollow space to bring the cold into contact also with the interior of the shafting
itself.
Improvements for Preventing the Overheating of Revolving Shafts,
and for Cooling the same if Overheated.
I MORTIMER EVANS of the Savile Club Piccadilly Civil 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:-
It is well known that shafting running at a high speed or under considerable
pressure often heats to an inconvenient or even dangerous extent this is especially
so when the lubrication becomes defective. The object of this invention is to
prevent this overheating or to reduce the heat if generated.
To effect this I apply the cold derived from the expansion of a highly compressed

page_text: gas or gasses and I prefer to allow such gas or gasses to do work in expanding that
a very low temperature may be obtained.
In conjunction with such expansion I in some cases employ a volatile liquid
or liquids such as alcohol or ether which by their rapid evaporation cause
extreme cold.
I also take advantage of the pressure of such gas or gasses to assist the
lubrication of the bearings to be cooled and to effect this I force the lubricant by
the pressure of the gas through and about the rubbing surfaces as desired.
In carrying my invention into practice I sometimes use the gas or gasses
obtainable from manufacturers in strong steel tubes and in a highly compressed
form.
In other cases I provide for the condensation of gas or air either by power
supplied by the shaft itself or by suitable machinery in the immediate vicinity of
the bearings to be cooled. By these means and the intervention of powerful
condensing pumps the air or gas may be highly compressed and the newly
compressed gas being deprived of its heat by a suitable cooling device is then
available for cooling purposes and may be conveniently substituted for the
compressed tube arrangement shewn in the drawings.
In Figure 1 P shews a pedestal bearing S a shaft and B. B. the brasses in which
the shaft revolves. P¹ is the pedestal cover. G is a tube or reservoir filled with
the condensed gas or gasses g is the valve attached to the reservoir and g' g² the
pipe and valve leading to an annular space inside the pedestal and surrounding the
brasses in which the shaft rotates. This is also shewn in section in Figs. 2 and 6.
9 is a passage lending from the annular chamber through the cover P to the
valve through which the liberated gas or gasses either escapes into the open air
or is led away by a pipe attached thereto as may be desired. The action of this
arrangement is as follows. On opening the valve g the compressed gas rushes
through this valve into the pipe gl and the auxilliary valve g' it passes thence into
and around the annular chamber and expanding in its course and in the annular
chamber produces intense cold and by abstracting the heat from the metal at once
lowers the temperature of everything with which it comes in contact and also by
conduction the whole mass of the bearing and shaft.
Fig. 2. is a section of Fig. 1 taken through the line of piping and the annular
chamber and passages in it as in Fig. 1. G is the reservoir. 9¹g² 9' 3ª g¹ the
various valves and passages.
Fig. 6 is a section taken longitudinally through the centre of the shaft and
pedestal in this figure S₁ shews the passage for the gas or gasses g the annular
chamber and g the escape cock as in Figs. 1 and 2.
Fig. 3 shews the same arrangement as Fig. 1 with the addition of the apparatus
provided for oiling and lubricating the shaft. In this fig. O represents the oil
vessel which is about 3 parts filled with oil O¹ being a screwed cup by means of
which the vessel may be replenished. The pipe (in this fig.) is continued:
upwards and leads through the valve o attached to it into the vessel O above the
surface of the oil. o is a pipe leading from the bottom of this vessel and beneath
the surface of the oil through passages os in the pedestal P (Fig. 4) and through
the lower brash to the bearing surface between the shaft and the brasses and is
therefore directly in communication with the rubbing surfaces this passage is
sufficiently to the side of the annular space to avoid communication with it and
is shewn in section by the dotted line Fig. 6. These passages are also shewn in
Fig. 4 which is a section taken through the line of these passages and in which the-
lettering corresponds to Figs. 3 and 6.
When lubrication without the cooling process is desired the valve g is closed
and on opening the valves g and o the pressure of the gas is made to bear on the
surface of the oil in vessel O and it is thence caused to flow through the passages
above described until it reaches the rubbing surfaces between the brasses and the
shaft and by a simple manipulation of these valves the oil can be forced in almost
any quantity through the whole length of the bearing expelling at the same time

page_text: the exhausted and dirty lubricant and providing the rubbing surfaces with a full
supply of clean fresh oil. When it is desired to lubricate and cool the bearings at
the same time the valve g may be opened simultaneously with valve o until the
desired effect is attained.
Fig. 5 shews the same arrangement as Fig. 3 with the addition of a farther
vessel E made to contain ether alcohol or other volatile liquid. This vessel being
partially filled with ether alcohol or other volatile liquid and the valves e. el being
opened the pressure of gas from the reservoir G can be made to drive the desired
quantity of ether through its communication pipe into the pipe g' as shewn and the
valve g being opened at the same time the ether and ether vapour is carriet along
with the compressed gas through the passage g' into the pedestal P, Figs. 2 and 6,
and with it into the annular space and from it through the valve gas before
described. It will be seen that these valves may be so manipulated as to pass the
ether or alcohol either alone or in conjunction with the gas as may be desired.
I do not confine myself to the use of the annular space shewn in the above figures
which are only intended to make the action of the invention clear. In some cases
I groove the brasses on their outer surfaces and pass the expanding gas through
them and between them and the pedestal and the pedestal cap and cause the gas
thus to circulate through the whole length of the bearing whence it is returned to
the air as before through the cock g or it may be made to escape if desirable
through appertures conveniently formed in the front and back faces of the brasses.
In carrying this into effect I so arrange the grooves and passages between them
as to obstruct or baffle the gas in its expansion or escape as much as possible and
so cause it to do work in escaping with the object of still farther lowering the
temperature. For this purpose also I sometimes fill the annular space before
mentioned with iron filings turnings &c. thus obstructing still farther the expansion
and escape of the gas.
When the shaft is hollow I sometimes avail myself of this hollow space as a
chamber in which to expand the gas thereby increasing the cooling effect by
cooling the shaft from the inside.
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
First. In methods of cooling heated bearings or for preventing their becoming
heated the application of the cold produced by the expansion of a highly
compressed gas or gasses in or about the parts where the heat is generated
substantially as described.
Second. The combination of the process as stated in the previous claim for the
production of cold by the expansion of a highly compressed gas or gasses with the
previous or simultaneous injection therewith of a highly volatile liquid or liquids
such as ether alcohol &c.
Third. The method of lubrication by which the lubricant is forced into the parts
to be lubricated by the pressure of compressed gas or gasses substantially as
described.
Fourth. The combination of Claims No. 1 and No. 2 whereby simultaneous
lubrication and cooling may be effected.
CL
1007
MORTIMER EVANS.