IMPROVEMENTS IN AND APPERTAINING TO MACHINERY OR APPARATUS FOR COMPRESSING AMMONIACAL AND OTHER GASES, PARTS OF WHICH IMPROVEMENTS ARE ALSO APPLICABLE TO MACHINERY FOR COMPRESSING AIR AND TO OTHER PUR- POSES.
Year: 1878

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields, in the
County of Middlesex, Gentleman, for the Invention of "IMPROVEMENTS
IN AND APPERTAINING TO MACHINERY OR APPARATUS FOR COMPRESSING
AMMONIACAL AND OTHER GASES, PARTS OF WHICH IMPROVEMENTS ARE ALSO
APPLICABLE TO MACHINERY FOR COMPRESSING AIR AND TO OTHER PUR-
POSES. A communication from abroad by Edgar Gaylord Wheeler, of New
York. in the United States of America.
Sealed the 4th April 1879, and dated the 4th October 1878.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson at the
Office of the Commissioners of Patents on the 4th October 1878.
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman. "IMPROVEMENTS IN AND APPERTAINING TO MACHINERY OR APPARATUS
FOR COMPRESSING AMMONIACAL AND OTHER GASES, PARTS OF WHICH IMPROVE-
MENTS ARE ALSO APPLICABLE TO MACHINERY FOR COMPRESSING AIR AND TO
OTHER PURPOSES." A communication from abroad by Edgar Gaylord Wheeler, of
New York, in the United States of America.
In engines used for compressing ammoniacal and other gases it is of great import-
ance that the compressed gases should be as completely as possible expelled from
the compression cylinder at the end of each stroke of the piston. In order to effect
this it is necessary in the first place that the passages leading to and from the
valves should be so constructed as to contain as little as possible of undischarged
compressed gas when the valves are shut, and yet allow ample area for the passages
of the gases into or from the compression cylinder when the valves are open.
In carrying out this Invention in order to effect this object the inlet and
delivery valves are constructed with flat faces resting on flat seatings and the
opening through the thickness of the metal is filled up by means of a projection or
boss on the valve below the seating of an angular or conical form, the opening in the

page_text: metal being also of angular or conical form, so that when the valve is down upon
its seating the whole space is filled up, the projection of the valve being nearly in
contact with the sides of the opening, and when the valve is lifted off its seating
the sides of the projection recede from the sides of the opening by reason of its
angular form, leaving an enlarged space for the passage of the gas or air. It is
preferred to make the valves of circular form, but they may be made of rectangular
or any other convenient form, and the projecting ends may be made to take
the guiding pins, being hollowed out for that purpose.
It is also essential that the piston should approach the cover so closely at the end
of its stroke in order to discharge the whole, or as nearly as possible the whole of
the compressed gas; that great risk would arise of the piston coming in contact
with the cover and so causing injury to the apparatus or breaking the joint of the
cover. In order to prevent this according to one arrangement the piston is faced
with india-rubber, or with a plate cushioned on india-rubber. Another mode of
effecting this object is to apply in connection with the cross head outside the
cylinder a powerful spring, the strength of which is so adjusted as to stand rigid
against the intended working pressure in the compression cylinder, but to yield or
give way to any excess of pressure or undue strain. In connection with the india-
rubber it is also proposed to render the piston rings self-expanding in proportion to
the pressure in the cylinder, by bringing the inner surfaces of the piston rings into
contact with or so applied to the outer periphery of the india-rubber discs or rings,
that pressure applied to the face of the latter is transmitted radially to the piston
rings and so presses them outwards.
Considerable difficulty has been experienced with the piston working in a closed
cylinder in engines for compressing gases, especially where great pressures are used,
owing to the difficulty of maintaining the pistons perfectly tight, and the con-
sequent escape of gas from the pressure side of the intake side of the piston which
fills up space on the intake side that should be occupied only with the new charge
of gas entering the cylinder, and thus causes a great per-centage of loss in the total
volume of gas compressed. In order to avoid this difficulty in lieu of the enclosed
piston a plain ram or plunger is used, the same working in a cylinder bored
accurately to fit it with piston rings or packing of the description above referred
to at the end of a ram, and also a gland packing at the front end of the cylinder
where the ram enters it. By this means any leakage past the ram piston passes
into the outer air and not round to the intake side, and can be at once detected
and checked by closing in the gland. Two rams bolted or otherwise connected
together may be employed working in two cylinders placed opposite one another,
thus making a double-acting machine, and the cushioning arrangements above
described applied thereto, or the cushioning may be effected by means of a thick
slab of india-rubber inserted at the connection of the two rams or to the cross head
outside the cylinders, or by applying round the bearings of the joint pin in the
cross head a thick ring or rings of india-rubber. The rams are also made hollow
so as to receive water, glycerine, or other liquid for keeping them cool.
In order to maintain the glands perfectly tight and at the same time avoid the
excessive friction arising from the ordinary description of screwed up glands, there
is applied to the glands a liquid or semi-liquid packing of glycerine or other sub-
stance which may serve to lubricate the ram. A pressure is applied thereto
sufficient to overcome any tendency of the gas to escape through such packing.
This pressure may be applied by means of a weighted piston or plunger working in
a chamber filled with the fluid or semi-fluid substance, so that any waste or escape
of the substance is constantly being made up or supplied by the gradual descent of
the the weight upon which is rendered sufficient to keep the packing tight
against any tendency of the gas to escape any of the packing substance that may
escape being returned to the ram chamber and used over again. Any convenient
number of grooves may be used in the gland filled with the fluid or semi-fluid sub-
stance, and for additional security an ordinary screwed up gland may be applied at
the exterior of the whole, which, owing to the checks effected by the liquid glands
ram,

page_text: would not require to be so tight as to cause an undue amount of friction. Or the
packing groove may be fitted with a paste composed of graphite and lead mixed
with a sufficient quantity of glycerine or other suitable substance, or may be filled
with suet, soft soap, mercury, or any other suitable substance.
The gland may also be packed by means of a thin sheet of metal bent round the
rod or the ram, outside which an india-rubber ring is applied, so that by applying
pressure by means of a screwed up gland to the edge thereof the india-rubber is
caused to swell out and press the metal sheet closer round the rod or ram.
The construction and arrangement of the valves may be modified in the following
manner:-The outlet or reduction valve is constructed to cover the whole base of
the cylinder which has an enlarged chamber at the end constructed to form a seat
for the outlet valve.
This chamber is an extension of the cylinder and is distinct from the cover which
closes the end. The inlet valve is in the outlet valve, and is by preference of the
same size as the ram or piston, and is so constructed as to form a perfectly even
smooth space when closed. The outlet valve has a long hollow stem accurately
turned to fit the cylinder head which is bored for it.
The stem of the outlet valve is closed at the end and has an opening or port
about the centre to the inlet valve.
On each side of this port are constructed as many grooves in the cylinder head
(having the valve stem) for the liquid or semi-liquid packing as may be necessary
to prevent any escape of gas or air from the outlet valve or chamber to the inlet
port, the necessary pressure being imparted to the packing by a weighted piston as
before described. The hollow stem of the outlet valve is winged and bored the
whole length to take the stem of the inlet valve which is provided with the
necessary spring at the end of the stem. The outlet valve is also provided with a
spring in the chamber, and in order to more equally balance the valve a port or
passage is constructed from the valve chamber to the back of the valve stem, in
order that the full area of the valve may have the full pressure of the discharge
and follow the ram or piston to its seat. The rams or pistons are so constructed
that they come into contact with the outlet valve, and if necessary lift it from its
seat at each stroke, thus insuring the full and complete discharge of the gas.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Henry Johnson in the Great Seal Patent Office on the 4th
April 1879.
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman. "IMPROVEMENTS IN AND APPERTAINING TO MACHINERY OR APPARATUS
FOR COMPRESSING AMMONIACAL AND OTHER GASES, PARTS OF WHICH IMPROVE-
MENTS ARE ALSO APPLICABLE TO MACHINERY FOR COMPRESSING AIR AND TO OTHER
PURPOSES." A communication from abroad by Edgar Gaylord Wheeler, of New
York, in the United States of America.
The said Invention relates to machinery or apparatus for compressing
ammoniacal and other gases or exhausting or compressing air, and it consists of the
improvements herein-after described in and appertaining to such machinery or.
apparatus whereby important advantages are obtained.
In carrying out the said Invention two rams or plungers are employed, which
äre connected together and are operated by a connecting rod and a cross head from
the crank shaft of an engine or by other convenient motive power. An clastic
inaterial is used, such, for example, as india-rubber, which prevents injury to the
parts in case the ram or plunger comes against the head of the cylinder, the object
being to insure the nearest possible contact of the ram or plunger with the cylinder
head so as to compress the ammoniacal gases.
Other improvements relate to the use of a compound yielding valve in the
cylinder head to admit the gas or air which is exhausted and to allow the escape of
the compressed gases, also to the means of packing or lubricating the rubbing
surfaces of the apparatus.
And in order that the said Invention may be fully understood I shall now
proceed more particularly to describe the same, and for that purpose shall refer to
the several Figures on the annexed 2 Sheets of Drawings, the same letters of
reference indicating corresponding parts in all the Figures.
Figure 1 (Sheet 1) of the accompanying Drawings represents a longitudinal
section of a portion of a pump, having applied thereto certain of the improvements
which form the subject of the said Invention, and Figure 2 is a sectional plan of
the same; Figure 3 is a sectional detail illustrating a modification of a portion of
the apparatus; Figure 4 (Sheet 2) is a longitudinal section of a portion of a pump,
having applied thereto a compound yielding valve according to another part of the
said Invention; Figure 5 is a transverse section taken through the valve and
valve cylinder; and Figure 6 is a horizontal section of the valve cylinder.
Referring to Figures 1 and 2, A, B, are two cylinders axially in a line the one
with the other and containing the rams or plungers C, D, which are connected
together by bolts. Through these rams passes a mortise at the part where they
are united, in which mortise is a cross head E with connecting rods F, F, at each
end passing to cranks upon a shaft which is revolved by suitable power, such, for
example, as a steam engine. Between the cross head E and the rams there are
interposed blocks of yielding material, such, for example, as india-rubber, as shewn
at J, J, the same being compressed by the bolts which hold the rams together.
This india-rubber will yield in case the end of the ram comes in contact with the
interior of the cylinder head A', thereby avoiding injury to the parts.
The induction valve K. is preferably placed in the middle of the cylinder head A¹,
and it is closed by a spring 1. The exit valves L, L, are also in the head A' and
open outwardly and are closed by the springs 2, 2, the said valves being coned upon
their seats with the smaller ends of the valves when closed flush or nearly so with
the inner surface of the head.
The inlet ports or pipes M and exit ports or pipes N are of the usual character.
It is found preferable in some cases to make the end of the ram C as a cap, as
shewn at C' in Figure 3, the said cap which is formed with a rim C² being bolted

page_text: to the ran C, and provided with blocks 4 of india-rubber or similar elastic materials
to allow the end of the ram to yield in case of contact with the head A'. The
nuts 5 on the connecting rods allow for adjusting the position of the ram to the
cylinder; but as variations in temperature may dorange the adjustment, and it is
necessary that the ram should come up and just touch the head,. the yielding
inaterial is introduced at J or 4 to avoid accident.
It will be understood that the cylinder B with its ram D and valves is in all
respects similar to the cylinder A with its ram C and valves, as herein-before
described, and therefore requires no special description.
Another part of the said Invention relates to the use of a compound yielding
valve in the cylinder head to admit the gas or air which is exhausted and to allow
the escape of the compressed gases. This part of the Invention is illustrated in
Figures 4, 5, and 6 (Sheet 2) of the Drawings.
The end A of the pump cylinder A forms a seat for the valve O which is carried
upon a tubular stem O¹ sliding in the valve cylinder P, the valve being forced
towards the seat by the spring 8. This valve forms the eduction valve, and it
yields and opens to the pressure of the gases and also to the pressure of the end of
the ram C in cases where the said ram comes in contact with the valve as it
approaches the end of the stroke. On the return movement of the ram the valve
moves with the same until its edge rests upon its seat, and then the induction
valve is opened by the gases as they rush into the vacuum formed by the retiring
ram. When the ram commences to move towards the valve Q the spring 10 upon
its stem 11 closes the valve and the gases are expelled past the valve O as
before.
.
The passage way 12 connecting from the induction chamber containing the
valve O to the space 13 behind the tubular valve stem o' produces an equalization
of the pressure, and allows tliec valves to move without hindrance by any
unbalanced pressure.
The pump cylinders A, B, and the valve cylinder P are formed on their interior
with annular grooves 15 around the rams C, D, and tubular valve stem O' respec-
tively. These grooves may be filled with suitable material, such, for example, as
steel or leather rings or other packing material, so as to render the parts air-tight.
It is preferred however to use thick heavy oil, tallow, or glycerine, or glycerine
and finely pulverized plumbago or similar material, the same being supplied into
these grooves from a reservoir or vessel (such, for example, as is shewn at V in
Figure 1, Sheet 1) under pressure from a ram or plunger V1, the vessel V being
connected with the annular grooves in the cylinders by pipes 16 and cross
chambers 17 from one groove to the other.
The pressure is sufficient to maintain a supply of the lubricating materials in
the grooves and effectually prevent leakage, and there will be but little waste of
such semi-liquid material when the parts are properly constructed.
The cylinders A and B should be surrounded with a water jacket as usual for
cooling the same.
Having now described and particularly ascertained the nature of the said
Invention, and the manner in which the same is or may be used or carried into
effect, I would observe in conclusion that what I consider to be novel and original,
and therefore claim as the Invention secured to me by the herein-before in part
recited Letters Patent is,-
First. The combination with the two rams C and D in the cylinders A and B of
the cross head E, connecting rods F, and elastic material intervening between
the cross head and the rams, substantially as and for the purpose herein-before
described.
Second. In a plunger pump the false head C' with the rim C bolted to the end
of the ram in combination with the india-rubber springs or cushions 4 between
the ram and the head, substantially as and for the purpose herein-before
described.
Third. The combination with the pump cylinder and ram of the valve O closing

page_text: against the end of the cylinder and the valve Q within the valve O and having its
seat in the said valve, substantially as herein-before described.
Fourth. The combination with the valves O and Q of the tubular stem 0¹ to
the valve and the stem 11 to the valve Q, the axis of the valves coinciding, as
herein-before described.
Fifth. In a plunger pump the annular grooves around the interior of the cylinder
at the place where the packing for the ram or plunger is required in combination
with means for supplying into such annular grooves the lubricating material under
pressure, substantially as herein-before described.
Sixth. The tubular valve stem O' forming an induction port and the containing
cylinder P and inlet pipe in combination with the valve Q, the axis of which is in
the tubular stem of the valve O, substantially as herein-before described.
Seventh. The tubular valve stem O', valve O, and cylinder P, in which the said
tubular valve stem slides in combination with the port or passage connecting the
'rear end of such cylinder with the exit chamber of the pump, substantially as
herein-before described.
Eighth. The employment in combination with the range of grooves around the
interior cylindrical surface of the valve chamber of a tubular connection to such
grooves and a lubricating material supplied under pressure to the same, substantially
as herein-before described.
In witness whereof, I, the said John Henry Johnson, have to this my Specifi-
cation set my hand and seal, the Fourth day of April, One thousand eight
hundred and seventy-nine.