Improvements in or relating to Gas Compressing Pumps and their Application to Refrigerating Apparatus.
Year: 1891

page_text: Date of Application, 2nd Jan., 1891-Accepted, 28th Mar., 1891
COMPLETE SPECIFICATION
Improvements in or relating to Gas Compressing Pumps and their
Application to Refrigerating Apparatus.
I, CHARLES GUSTAVUS MAYER, of 744, Broadway, in the City, County, and
State of New York, United States of America, Mechanical 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 relates generically to certain improvements in gas pumps and their
connections, whereby greater economy of operation is effected and improved means
introduced for producing uniform cooling temperatures in a much more satisfactory
manner than any system heretofore placed upon the market.
One of the objects of my present invention is to facilitate the starting of gas
pumps or compressors as this operation has hitherto been attended with several
serious drawbacks. Heretofore in starting a gas pump the high pressure or com-
pressed ammonia gas, which exists above the discharge valves of the pump, creates
a pressure of from 150 to 200 pounds per square inch on the valves, requiring an
accumulation of power or momentum to overcome. The starting against this
pressure has, as above stated, been heretofore accomplished under difficulties, and
has generally required manual assistance in passing dead centres until a headway
has been gained.
To dispense with this serious difficulty, I provide means for shutting off the high
pressure gas temporarily above the discharge valves of the pump and opening a
pipe or pipes which connect the low pressure directly to the high pressure side of
the pump so that the pump may be started with the high pressure shut off until a
certain momentum is obtained. When the pump has attained the desired speed,
the high pressure gas can be turned on as will be hereinafter more fully described.
Another object of my invention is to effect certain economy in connection with
the steam engine employed to operate the gas pump, and for this purpose I introduce
a compound engine as by such means I am enabled to reduce the expense of operating
the pump, as will be hereinafter more fully described.
1
Another object of my invention is to dispense with certain disagreeable features
which have heretofore existed in nearly all gas pumps, that is, the noise produced
by the valve striking its outer seat upon its upward or outward movement.
dispense with this shock and the consequent noise by introducing a novel cushioning
device which receives the impact of the valve stem and prevents the valve from
striking with any force against the outer seat.
Another object of my invention is the providing of a novel and useful stuffing
box, which is particularly adapted to operate in connection with gas pumps and is
arranged with packing chambers of different sizes, one being contiguous to and the
other remote from the gas pump, the inner one being adapted to pack against high
pressure gas and the outer one against low pressure gas and the two packing
chambers being provided with an intermediate oil chamber that will receive and
absorb all of the volatile fluid escaping through the inner packing from the
gas pump.
In this
Another object of my invention, is the providing of a novel means for cooling
the lubricating material of the pump by withdrawing it from the high pressure trap,
or reservoir and directing it into the low pressure trap or reservoir.
connection I provide means for cooling the stuffing box also by leading the oil or
lubricating material from the low pressure trap into such stuffing box by means of a
natural circulation or otherwise, all of which will be hereinafter more fully
described in connection with the drawings and particularly pointed out in
the claims

page_text: It is also desirable to provide means for handling the oil or lubricating material
in such a manner that, as it passes through the stuffing box the large amount of
ammonia gas under high pressure, which it carries with it will not escape, as such
loss would entail considerable expense and would also be extremely disagreeable
and even sometimes dangerous. Again, the oil used in the pump cylinder and which
is absorbed and carried off with the high pressure gas to the receiver, when returned
to the pump to be re-used is then released from pressure and the ammouia contained
in the oil evaporates, thereby partly filling the suction side with gas, consequently
the vacuum in the pump is proportionately destroyed, thereby reducing the efficiency
of the pump and also decreasing its refrigerating capacity. This defect I also obviate
as will be hereinafter pointed out.
Referring to the accompanying drawings which form part of this Specification.
Figure 1 is a general view showing a refrigerating system consisting of a gas
pump or compressor, a brine tank, gas condenser with high and low pressure
receivers, and a liquid oil receiver all connected by necessary pipe system.
Figure 2 is a partial section and side elevation of a gas pump provided with my
improved valves.
Figure 3 is a longitudinal section of my improved stuffing box.
Figure 4 illustrates a method of providing a circulation of cool oil through the
stuffing box of the pump.
Figure 5 is a detail view.
1 is a gas pump which exhausts the gas through the suction pipe 2 in the low
pressure system and discharges it into the pipe 3 in the high pressure system, see
Figure 1.
From the gas pump the discharge pipe 3 conveys the compressed gas into the
high pressure trap 4. The pipe 3 is provided with a valve 5 and extends some
distance into the trap 4. The pipe 6 which commences at the top of trap 4
conveys the compressed gas away from the trap into the top of the condenser coil 7
through which the gas flows and passes into the liquid receiver 8 by means of the
pipe 9 having the valve or valves 10.
During the passage of the gas through the coil 7 the heat is extracted from the
gas which passes into the receiver 8 in a liquid state under the existing high or
condenser pressure. From this liquid receiver 8 the liquid gas is conveyed by
means of the pipe 11 from, or near, the bottom of the receiver 8 into the top of the
refrigerating coil 12 having the valves 13 and 14 between.
Immediately beyond the valve 14 the liquid gas is relieved from the high or
condenser pressure and enters the low pressure system and follows the refrigerating
coil 12 from which it passes through the pipe 15 into the low pressure trap 16, the
said pipe entering the trap through the top. During this passage the gas is
allowed to satiate itself with heat taken from the brine in which the coil or coils 12
are immersed. From the top of the same trap the pipe 2 having the valve 17
conveys the gas to the suction valves of gas pump 1 to be re-compressed and to
go through the same evolution or transformation. It will be seen by the foregoing
description, that the refrigerating apparatus containing the gas is divided into two
distinct systems.
First The low pressure system in which the liquid gas is allowed to expand or
evaporate in order to produce the necessary low temperature in the gas volume, and
in which the gas is allowed to absorb heat.
Second: The high pressure system in which low pressure gas, after passing
through the low-pressure system and being satiated with heat, is compressed in
order to change the heat contained latent in the low pressure gas into sensitive heat,
thereby increasing the temperature of the gas sufficiently to be taken up or absorbed
by water, or other conductors of heat, whereupon the gas under pressure caused by
its own resistance will again collapse into the liquid state, and be ready to go through
the same evolution.
The first or low pressure system commences on the lower side of the valve 14,

page_text: passes through the coil 12, through the pipe 15 into the low pressure trap 16 and
from thence through the pipe 2 into the gas pump 1.
The second or high pressure system commences at the discharge valve or
valves 5 of the gas pump 1 and extends through the pipe 3 into the high pressure
trap 4 and from there through the pipe 6 into the coil 7, through the pipe 9 into
the liquid receiver 8 and then through the pipe 11 to the upper side of the
valve 14.
That part of my invention which relates to the relieving of the pump from high-
pressure resistance when starting is accomplished by the following means:-
Referring to Figure 1 :-
Between the valve 17 on the suction pipe 2 of the low pressure system and the
valve 5 on the discharge pipe 3 of the high-pressure system, I arrange a connecting
pipe 18 having thereon valves 19, 20; this pipe enters the suction valve 17 above
the valve seat and enters the discharge valve 5 below the valve seat. Between
the valves 19 and 20 on the pipe 18 is connected the pipe 21 provided with the
valve 22.
When the gas-pump is at a stand-still, the conditions under which it ordinarily
has to start up, are the following:
The high, or condenser pressure, begins immediately on top of the discharge
valves of the pump, extends through the pipe 3 and the valve 5 and high pressure
trap 4 to the condenser 7 through pipe 6. The low or back pressure begins imme-
diately from the bottom of the suction valves 2" (Figure 2) of the pump and extends
through the pipe 2, the valve 17, the low pressure trap 16, the pipe 15 to the
refrigerating coil 12. If the gas pump 1 is to be started up, the gas contained in
the pump cannot be discharged in the ordinary manner until the gas pressure in the
pump is great enough to lift the discharge valves 3ª (Figure 2) plus the condenser
pressure thereon, which as previously stated varies between 150 to 200 pounds per
square inch.
To obviate this difficulty, and to be able to start up the gas pump against low
pressure is one of the objects of my invention. The method of operating so as to
accomplish the said object is as follows:-
Before starting the gas pump the valves 17 and 5 being closed, the valves 19
and 20 in the connecting pipe 18 are opened, allowing a free passage of the high
pressure gas between the discharge valves of the pump and valve 5 to escape into
the low pressure system in pipe 2. This operation reduces the pressure on the dis-
charge valves 3ª of the gas pump 1 to that existing in the low pressure system
which is hardly ever above 30 lbs. to the square inch, and the pressure, on the
suction and discharge valves of pump 1, becomes equalised. When the pump
piston 38 begins to move, the discharge valves 3" of pump will immediately open,
thus letting the gas escape through pipe 18 into the low pressure system while the
pump suction reduces the volume of gas existing in the pipe 2 between the suction
valves 2ª of the pump and valve 17.
By this means the pump is started up as easy as an ordinary engine and is allowed
to gather momentum, or the desired rate of speed, after which the valves 19 and 20
are closed, valve 5 is opened full and valve 17 gradually. The gas is then per-
mitted to flow into the high-pressure system.
The pipe 21, the lower end of which is open, is simply for the purpose of
exhausting the air from the apparatus before filling the same with gas. Of course
the arrangement of the apparatus is immaterial and may be changed without
departing from the spirit of the invention.
In the working of a refrigerating apparatus, the combination of the gas pump
with the steam engine and which constitutes a part of my invention affords a more
economical and satisfactory arrangement than any hitherto employed. The piston
of the ammonia gas pump is reciprocated through the instrumentality of the pitman
connection with a crank wrist on the shaft having like crank and pitman connection
with piston rod of the steam engine.
The pistons of the properly encased primary and secondary cylinders of a

page_text: compound steam engine are connected by a rod common to both. A pitman connects
the free end of said rod to the wrist upon one end of a crank shaft, whose other end
carries a second wrist which is connected by a pitman with the piston rod of the
gas or ammonia pump 1.
The said gas pump, which is double acting, is provided with my improved valves
and stuffing box, see Figures 2 and.3.
These valves are constructed as follows:-
The casing 31 of the suction valve is cast integrally with the cylinder 32 of the
gas pump 1, and is provided with the cover 33.
Within the casing 31 are the lining or bushing 34 and the valve seat 35, said
valve seat being fitted in with a ground joint at 36. In the passage between the
valve 2" and the bore of the cylinder, a web 37 is cast, consisting of four or any
convenient number of arms at angles with the longitudinal movement of the
piston 38, the angle of the arms of the web 37 preventing any abrasion or cutting
of the piston 38. The web 37 is shown in detail in Figure 5 of the drawings.
This web 37 is of importance, in that, hitherto, accidents have occurred from the
valve 2ª being sucked into the cylinder, resulting from the loosening or breaking of
the stem 39 of the valve. The valve stem 39 is surrounded by the spring 40, one
end of which rests against the washers 41 and the other end against the head of the
spring casing 42, which forms a guide for the valve stem 39 and is screwed into the
cover 33 at 43. 44 is an adjusting screw provided with stuffing gland 45. A set
screw 46 also provided with a stuffing gland 47 allows an independent means of
insuring a tight joint at 36 by bearing against the end of bushing 34.
The discharge valve 3ª is enclosed in a similar manner, having the casing 48,
cover 49, bushing 50, valve seat 51 and the set screw 52 with its gland 53.
The spring casing or guide 54 is. screwed into the cover 49, against which one
end of the spring 55 bears, the other end of the spring 55 rests against the shoulder 56
on the valve stem 57, the upper end of which, when the valve is forced up by
the discharge of the pump, strikes against the steel head 58 of the pin 59, thereby
compressing the rubber or packing ring 60. A steel ring 61 bears against the
adjusting screw 62 having its gland 63.
By thus cushioning the valve, it is rendered practically noiseless.
The stuffing box 64 (see Figure 3) is constructed as follows:--
The stuffing box containing the packing chamber 65 is cast integrally with the
cylinder head 66 of the gas pump 1 and is provided with the nut 67 having the
jam nut 68 and the gland 69. The oil chamber 70 is formed in the casing 71 and
the said casing is provided with the outer and smaller packing chamber 72. The
outer end of the stuffing box is provided with a gland 73, a nut 74 and also with a
jam nut 75. The oil chamber 70 is tapped by the oil pipe 85, which is in connec-
tion with the low pressure trap 16. The nuts 67 and 74 have wrought iron
rings 67 and 74" shrunk on, for the purpose of strengthening them. The
spaces 76 and 77 are filled with rubber or soft packing to provide against any gas
escaping through the threads. The casing 71 is also provided with a shoulder 79
which is turned to make a ball joint with the nut 67 at 78 which is finely ground to
prevent any escape of gas.
The bearing surfaces between the gland 69 and the casing 71 are also ground
to produce a tight joint. It will be seen that the stuffing box consists of two
chambers for packing, one on each side of the oil chamber 70; the inner packing
chamber 65 must pack against high pressure gas, the outer chamber 72 against
the atmosphere or low pressure gas, in the oil chamber 70. Should any high
pressure gas escape through the inner packing 65, it will immediately expand
when it reaches the oil chamber 70 into low pressure gas, escaping through
pipe 85 into the low pressure system; consequently, the packing in packing
chamber 72 needs only to keep in low pressure gas or oil.
It will be seen that, owing to the great length of the stuffing box, that is to
say, from the inner end at 66 to the outer end at 74, see Figure 3, there will
be some liability to bind at the outer end of the stuffing box, where it is in

page_text: contact with the piston rod 30. A slight lateral vibration of the piston rod
would cause considerable friction at this point, but, by means of the ball joint
at 78, the stuffing box is permitted to vibrate in unison with the piston rod,
thereby preventing the unnecessary friction at this place, and also, by making
the joint more certain, prevents the escape of the volatile fluid into the outer
air that has found its way into the stuffing box.
My lubricating and oil cooling system is arranged as follows:-
From the bottom of the low pressure trap 16, the pipe 80, having the valve 81,
connects with the pipe 82 having the valve 83, the pipe 84 extending into the
bottom of the high pressure trap 4 and is provided with an extension pipe 90
having a valve 91, as shown.
From the side and from the bottom of the low pressure trap 16, I run the pipe 85
having a valve 86 into the stuffing box 64 of the gas pump 1. From this pipe 85,
a branch pipe 87 is taken and led or connected into the low pressure system or
suction pipe 2, preferably at the valve 17. This pipe has the valves 88 and 20 in
the connection.
The high pressure trap 4 and low pressure trap 16 have, as shown, glass
gauges 89 to indicate the oil line.
The method of operation is as follows:-
When the machine is to be charged with oil, the end of the pipe 90 is turned into
an oil barrel or tank and connected with the low pressure trap 16 in which a partial
vacuum is produced by means of the gas pump 1, then, valve 83 being closed,
valves 91 and 81 are opened and the oil allowed to rush into the trap 16 by the
atmospheric pressure behind it, until the glass gauge 89 shows a sufficient quantity,
when both valves are again closed.
When the oil is to be taken out of the machine, the pressure in the trap 16 is
reduced to two or three pounds, the end of pipe 90 turned into a barrel or tank and
the valve 83 being closed and valve 81 entirely opened and valve 91 so manipulated
as to regulate the oil flow.
During the working of a refrigerating machine, the return gas, flowing into the
trap 16 on its way to the pump suction, is always cold enough to reduce the ten-
perature in the oil sufficiently for cooling purposes. For the purpose of cooling
and lubricating the stuffing box, the valve 86 is opened, allowing the heat generated
in the stuffing box 64 to be conducted through the pipe 85 into the body of the oil
volume held in trap 16, where it is absorbed by the return gas on its way to the
gas pump 1.
For the purpose of lubricating the gas pump 1, the valves 88 and 20, on the
branch pipe 87, are opened fully and enough of the lubricant is let into the gas
pump through valve 17 and suction pipe 2 to keep the piston from cutting.
The oil used as lubricant accumulates in the high pressure trap 4 and is sent
from there by its own pressure through the pipe connection 84, 82 and 80, back
into the low pressure trap 16, when the valves 83 and 81 are opened.
The lubricant under the high pressure existing in trap 4 contains from 30
to 35 per cent. of gas, which it loses when released from that pressure. It also parts
with its heat at the same time.
By taking the lubricant to cool my stuffing box from the low pressure trap, as
shown and described, the outside packing of the stuffing box 64 needs only to be
tightened against low pressure gas or oil, thus placing the stuffing box of the
double acting pump which I employ on the same footing with that of the single
acting pump.
The pipe 85 may be constructed to extend from the oil chamber 70 of the
stuffing box 64 to the low pressure trap 16, and the circulation may be back and
forth through this pipe or it may be connected with the discharge of an oil pump 92,
the suction of which is connected by pipe 93 to the bottom of oil tank 94, said oil
tank having a cooling apparatus, as, for instance, a coil 95, as shown in Figure 4,
through which cool brine is circulated.

page_text: The oil is forced from the pump 92 into the lower side of the stuffing box 64,
where it necessarily becomes heated, and out again from the upper side through
pipe 96 into the oil cooling tank 94.
The high pressure gas contained in the oil which enters oil tank 94 through
pipe 96 is permitted to escape through the pipe 97 into the low pressure system.
Otherwise, the accumulation of gas in oil tank 94 would soon be equal in pressure
to that escaping into the oil chamber 70 in stuffing box 64 and would force itself
through the outside packing chamber 72 into the outside atmosphere.
A modified form of this circulating system is shown in dotted lines in Figure 4.
In this case the oil flows by gravity from the oil tank 94 through pipe 85 into the
stuffing box 64 and the heated oil in pipe 96 rises to its level in tank 94 and
circulates by means of the heat generated in the stuffing box 64. These latter con-
structions may be employed where the pipes are of considerable length or where
there are two or more of the refrigerating machines in use.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, I declare that what I
claim is :-
1. A gas pump and gas pump system, constructed, arranged and adapted to
operate substantially as hereinbefore shown and described, and for the purposes set
forth.
2. In a gas pump that pumps against high pressure, the method of shutting off
the high pressure and pumping against low pressure until a certain speed has been
obtained before turning on the high pressure.
3. In a gas pump, the combination with said pump, of a pipe or pipes leading
directly from one side of the pump to the other, said pipe or pipes being provided
with a valve or valves whereby the pump can begin pumping and attain a certain
speed before the high pressure gas is turned on.
4. In combination with a gas pump, the high and low pressure tanks or receivers,
pipes leading therefrom and thereto provided with valves, and a by-pass pipe also
provided with valves for the purpose of cutting off the high pressure and permitting
the pump to operate against low pressure when starting.
5. The combination of the gas pump 1, the pipes 2 and 3, the tanks or receivers 4
and 16, the valves 5 and 17 and the by-pass pipe 18 provided with the valves 19
and 20, all arranged substantially as shown and described with particular reference
to Figure 1 of the accompanying drawings whereby in starting the pump the high
pressure will be cut off and the pump may be permitted to operate against low
pressure only, until a certain speed has been obtained.
6. The combination of the gas pump with an arrangement of pipes and traps or
receivers forming a system of natural circulation for the ammonia, or volatile fluid,
between the high and low pressure traps or receivers.
7. The combination of the gas pipe 1, the pipe 3, trap or receiver 4, pipe 6,
condenser 7, ammonia receiver 8 and its connecting pipe 9, brine tank 12 and its
connecting pipe 11, low pressure trap or receiver 16 with its connecting pipe 15
and the pipe 2 leading to the gas pump, all arranged substantially as and for the
purposes set forth.
8. The combination of the gas pump constructed and arranged substantially as
described with a compound engine connected to said gas pump and adapted to
operate for the purposes set forth.
9. In a gas pump, the combination of the discharge passage provided with a
valve, with a cushioning device for preventing the sudden shock and consequent
noise from the outward and upward movement of the valve.
10. In a gas pump, the combination of the discharge passage provided with a
valve having a valve stem, a pin 59 having a head 58, a rubber or packing ring 60,
a washer 61 and the means for adjustment, substantially as shown and described.
11. In a gas pump, the combination with the suction and discharge pipes and the

page_text: valves having valve stems, valve stem casings 42 and 54 and the valve springs 40
and 55 whereby the valves 2 and 3 are retained in their proper and normal
position as shown and with particular reference to Figure 2 of the drawings.
12. In a gas pump provided with suction and discharge passages, the covers 33
and 49 provided with bushings 34 and 50 and means of adjustment consisting of
valve seats 35 and 51, ground joints 36 and 36", and means consisting of set
screws 46 and 52 and glands 47 and 53, with particular reference to Figure 2 of
the drawings, all arranged substantially as and for the purposes set forth.
13. The combination of a gas pump, with a stuffing box having two packing
chambers, one of which packing chambers is adapted to pack against high pressure
and the other against low pressure.
14. The combination of a gas pump, with a stuffing box having a packing
chamber arranged contiguous to the gas pump for packing against high pressure, a
packing chamber at the outer end of the stuffing box for packing against low
pressure and an oil chamber located between the two packing chambers and adapted
for the reception and circulation of the lubricating and cooling material.
15. The combination of a gas pump with a stuffing box provided with a packing
chamber 65 arranged contiguous to the gas pump, a gland 69, nut 67, jam nut 68,
oil chamber 70, casing 71, packing chamber 72, gland 73, nut 74 and jam nut 75, all
arranged substantially as and for the purposes set forth, with particular reference to
Figure 3 of the drawings.
16. In combination with a gas pump, a stuffing box adapted to pack against high
and low pressure gas, and provided with a packing chamber 65, a nut 67, casing 71,
said casing and nut having a ball joint 78 which will permit the outer ends of the
stuffing box to turn on the ball joint and vibrate in unison with the piston rod
without wear and tear, all arranged with particular reference to Figure 3 of the
drawings.
17. A stuffing box constructed substantially as shown and described with
reference to Figure 3 and provided with the re-enforce rings or collars 67 and 74",
the rubber or other suitable packings 76 and 77 and the nuts 67 and 74, all
arranged for the purposes set forth.
18. The method of cooling the lubricating material of a gas pump by with
drawing it from the high pressure trap and directing it to the low pressure trap.
19. The method of cooling the stuffing box of a gas pump by providing said
stuffing box with an oiling chamber and connecting it by means of a pipe with the
low pressure trap, thereby providing a natural circulation for the oil through the
oil chamber in the stuffing box and means for cooling it as set forth.
20. In a gas pump provided with a stuffing box substantially as shown and
described, and an oil chamber with pipes leading thereto and therefrom and a
pump 92 for keeping the said oil in circulation with particular reference to Figure 4
of the drawings.
21. In a gas pump provided with a stuffing box substantially as shown and
described with an oil chamber approximately centrally located therein, with pipes
leading thereto and therefrom and connected to the oil tank 94 with particular
reference to Figure 4 of the drawings.
22. In a gas pump, means for removing old and waste oil from the apparatus and
introducing fresh oil therein, which consists of the pipes 80, 82, 84, 90, the low
press are trap or receiver 16 and the valves 81, 83, 91, all arranged substantially as
shown and described and for the purposes of rejecting old oil and receiving new oil
from the exterior of the apparatus with particular reference to Figure 1 of the
drawings.
Dated this lot dow of Ianuary 1201
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Agents for the Applicant.