IMPROVEMENTS IN APPARATUS FOR COMPRESSING THE CONDENSABLE GASES
Year: 1884

page_text: I SAMUEL PUPLETT of Westmoors Knowle in the County of Warwick Engineer
do hereby declare the nature of my invention for IMPROVEMENTS IN APPARATUS
FOR COMPRESSING THE CONDENSABLE GASES to be as follows:-
of
In compressing any of the condensable gases heat is evolved which in gases
high tension is troublesome in various ways. To overcome these difficulties the
usual method is to circulate water around the cylinder and valve chests. In some
cases it has been found efficacious and more convenient to force into the compression
cylinder at each stroke a small quantity of the liquefied gas which instantly
vaporizes and thereby absorbs the heat of compression at each stroke of the pump
thus effecting isothermal compression and keeping the cylinder and piston at a
suitably low temperature-My invention relates to apparatus for injecting this
liquid into the compression cylinder âutomatically at the right time and in the
right quantity.
The apparatus consists of a small cylinder or receptacle conveniently placed on
or near the compression cylinder, containing piston or valve worked either by a
crosshead or direct from the crankshaft and so arranged as to give an intermittent
motion to the piston or valve rod-This cylinder or receptacle is connected by pipe
to the storage chamber of the liquefied gas and consequently this pipe cylinder or
receptacle is always filled with the liquid and is always under the condenser
pressure-There is also a passage or pipe from underneath the piston or valve into
the compression cylinder-The operation is as follows, at a predetermined point in
the stroke of the main piston, the piston or valve in the small cylinder is moved so
as to uncover the passage leading to the compression cylinder and in as much as at
this point of the stroke the pressure in the cylinder is very much less than the
constant pressure in the condenser a portion of the liquid gas in the small cylinder
is injected into the compression cylinder-the quantity being regulated by the
condenser pressure, the length of time the passage is uncovered and the area of the
passage, and once adjusted it afterwards needs no change-The liquid gas instantly
vaporizes on its entrance into the cylinder and the resultant gas is compressed
with that from the inlet valves and with it passes to the condenser and is there
reliquefied.
"
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A 2

page_text: I SAMUEL PUPLETT of Westmoors Knowle in the county of Warwick Engineer
do hereby declare the nature of my invention for IMPROVEMENTS IN APPARATUS
FOR COMPRESSING THE CONDENSABLE GASES and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:—
-
In compressing any of the condensable gases heat is evolved which in gases of
high tension is troublesome in various ways-To overcome these difficulties the
usual method is to circulate around the cylinder and valve chests-In some cases it
has been found efficacious and more convenient to force into the compression
cylinder at each stroke a small quantity of the liquefied gas which instantly
vaporizes and thereby absorbs the heat of compression at each stroke of the pump
thus effecting isothermal compression and keeping the cylinder and piston at a
suitably low temperature.
My invention relates to apparatus for injecting this liquid into the compression
cylinder automatically at the right time and in the right quantity.
In the accompanying drawings two forms of apparatus are shewn, both with
cylindrical valves, one having a reciprocating motion from the crosshead, the other
having a rotative reciprocating motion derived from the crankshaft.
With both the motion is intermittent and the time of actuation relative to the
position of the piston is fixed by a predetermined arrangement of the actuating
parts.
Fig 1 is a vertical longitudinal section of one form of the apparatus with the
valve in elevation.
Fig 2. is a cross section on line A-B.
a, cylinder of the compression pump-a' valve cylinder-b the valve-c the
valve rod connected to the valve in such a manner that the valve is free to move
at right angles to the rod-o metallic packing. c section of outer packing
chamber not shewn complete-d & d' inlet and outlet passages for the liquefied gas.
The top of the valve is cut away at e thus allowing a free passage for the liquid
to both ends of the cylinder and giving sufficient surface for the pressure to hold
the valve to its seating.
A motion of the valve in one direction uncovers the passage d¹ and allows the
liquid gas to pass into the cylinder of the compression pump until the return motion
re-covers the outlet.
Fig 3. is a vertical section of a modified form of the apparatus in which f is the
cylinder of the compression pump and f¹ the valve cylinder g the valve. h the
valve rod flatten at the inner end h¹ upon which the valve may have a slight
transverse motion h¹¹ collar formed on the rod-h lever-i flanged bushing that
supports one end of the rod-j & j¹ end covers of valve cylinder. k the spring that
holds the bushing to valve and valve to collar- sealing chamber encircling the
rod-m section of outer packing chamber not shewn complete-n passage connected
with inlet or suction pipe through which any gas that may pass the collar " is
withdrawn from the sealing chamber by the action of the pump. o and o¹ inlet
and outlet passages to and from the valve cylinder-The valve in this arrangement
has a slight rotative reciprocating motion imparted to it by means of the lever h¹¹.
The actuating motion may be by any of the various devices which are too well
known to need description.
The passage dor o is connected by a pipe to the storage chamber of the liquefied
gas and consequently this pipe is always filled with the liquid and is always
under the condenser pressure The passage d or o continues into the compression
cylinder.

page_text: The operation is as follows at a predetermined point of the stroke of the main
piston the valve in the smaller cylinder is moved so as to uncover the passage
leading to the compression cylinder and in as much as at this point of the stroke
the pressure in the compression cylinder is very much less than the constant
pressure in the condenser-a portion of the liquid gas is injected into the com-
pression cylinder the quantity being regulated by the condenser pressure the length
of time the passage is uncovered and by the area of the passage and once adjusted
it afterwards needs no change-The liquid gas instantly vaporizes on its entrance
into the compression cylinder and the resultant gas is compressed with the gas that
enters the cylinder through the ordinary inlet passage and with it passes to the
condenser and is there reliquefied.
From the foregoing description of the apparatus and its operations it will be seen
that by this arrangement a liquid may be injected into the compression cylinder at
predetermined intervals in prearranged quantities with a degree of certainty and
freedom from liability of accident scarcely attainable with small valves automatically
actuated.
It will be apparent that the compression cylinder may be regularly lubricated
by the same apparatus and in the same manner by the one operation; only
requiring that a reservoir of the lubricant under condenser pressure be from time
to time or continuously connected to the passage d or o in the valve cylinder or to
a separate passage through the cylinder and valve as shewn by dotted lines in
Fig. 3.
The metallic packing for valve rod shewn in Fig 1 is not new and is not
claimed except in combination with other parts of the apparatus believed to be
novel.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
First in apparatus for forcing liquids under pressure into the cylinders of
compression pumps at intervals that have a fixed relation with the speed or
revolutions of the crankshaft between each discharge, the utilizing of the pressure
of the liquid to be injected, in combination with mechanical devices devices for
opening and closing the valve at predetermined points of the stroke-substantially
as and for the purposes described.
Second-in apparatus for forcing liquids under pressure into cylinders of com-
pression pumps at intervals between each discharge the general arrangement
combining a cylindrical valve and valve rod so connected as to admit of a trans-
verse motion of the valve-and metallic packing for valve rod substantially as
shewn in Figs. 1 & 2 and for the purposes described.
Third-in apparatus for forcing liquids under pressure into cylinders of com-
pression pumps at intervals between each discharge the general arrangement
combining a cylindrical valve with one or more passages through it, having a
rotative reciprocating motion imparted to it-a valve rod arranged for actuating
the valve whilst admitting of a transverse motion of the valve-a collar with two
true faces formed on the rod-a flanged bushing forming support for one end of
the valve with one true face on flange-a spring that holds bushing to valve, valve
to collar and collar to seating a sealing chamber encircling the rod having a
connection to inlet pipe or passage and a rod packing out side the sealing chamber
substantially as shewn in Fig. 3 and for the purposes described.
Dated this 27th day of October 1884.
SAMUEL PUPLETT.