IMPROVEMENTS IN AIR COMPRESSORS AND ENGINES FOR OPERATING THE SAME PARTLY APPLICABLE TO PURPOSES " OTHER
Year: 1883

page_text: LETTERS PATENT to Charles William Potter, of Maida Hill, in the county
of Middlesex for an Invention of "IMPROVEMENTS IN AIR COMPRESSORS
AND ENGINES FOR OPERATING THE SAME PARTLY APPLICABLE TO
PURPOSES
"
OTHER
PROVISIONAL SPECIFICATION left by the said Charles William Potter
at the Office of the Commissioners of Patents on the 9th October 1883.
CHARLES WILLIAM POTTER, of Maida Hill, in the county of Middlesex
"IMPROVEMENTS IN AIR COMPRESSORS AND ENGINES FOR OPERATING THE SAME,
PARTLY APPLICABLE TO OTHER PURPOSES
"
These improvements in air compressors chiefly relate to those air compressors
which are operated directly by steam engines, but certain features of the invention
are applicable to compressors operated by belts or gearing.
One part of the invention relates to means of stopping the action of the
compressor without stopping its motion or the motion of the engine which drives
it, when the pressure of air in the receiver to which the compressor delivers the
compressed air exceeds a certain degree.
According to this part of the invention the compression is suspended partly or
wholly by opening communication between the ends of the compressor cylinder,
so that the whole or part of the air will be circulated back and forth from end
to end of the cylinder without being discharged into the receiver. This part of
the invention consists in the combination with the cylinder of a double-acting air
compressor, of pipes or conduits connecting the two ends of the cylinder, and a
pressure regulator adapted to be operated by an excess of air pressure in the
receiver, for the purpose of so controlling communication between the ends of the
cylinder through the said pipes or conduits as to allow the circulation of air from
end to end of the cylinder through the said pipes or conduits and so stop the
compressing action when the pressure exceeds the desired degree. This regulator
may consist of a cylinder, a piston and a valve connected with the said piston ;
or of a cylinder and a piston which is itself a valve. This part of the invention
further consists in the combination with the cylinder of a double-acting compressor
631....מ

page_text: provided with pipes or conduits for connecting its ends, and a pressure regulator
for controlling communication between the ends of the said cylinder through the
said pipes or conduits, as above mentioned, of an engine for operating the said
compressor provided with a throttle valve and connections through which the
said pressure regulator effects the closing of the throttle valve when it places
the ends of the compressor cylinder in communication and the opening of the said
throttle valve when it shuts off communication between the ends of the said
cylinder. By this means any unnecessary consumption of steam, when the
compressor is not performing any work by pumping air into the receiver, is
prevented.
In air compressors the cooling water is sometimes discharged directly into the
compressor cylinder by means of a pump worked by the compressor or its operating
engine and when the air is circulated back and forth from end to end of the
compressor cylinder as herein before described, it is necessary to diminish or stop
entirely the discharge from the water pump into the cylinder. To this end one
part of the invention consists in the combination with the compressor cylinder and
its pipes or conduits and pressure regulator for controlling communication between
the ends of the said cylinder, as herein before described, of a water supply pump,
and a valve which is so connected with the said pressure regulator that when the
latter operates to place the ends of the cylinder in communication through the said
pipes or conduits, it will also operate the said valve to admit air to the suction
pipe of the said pump, for the purpose of diminishing or cutting off entirely the
discharge of water by the pump.
The invention also consists in the combination of the compression cylinder
provided with pipes or conduits and a pressure regulator whereby the ends of the
cylinder will be placed in communication when desired, as hereinbefore described,
a pump for the supply of cooling water to the said cylinder, having an air inlet
valve in its suction pipe, and connections between the said regulator and the
throttle valve of the engine which works the compressor and between the said
regulator and the said air valve, whereby the operation of the pressure regulator
by an excess of air pressure will simultaneously place the ends of the compressor
cylinder in communication, close or partly close the throttle valve of the engine,
and open the air inlet valve to admit more or less air to the suction of the
pump for the purpose of diminishing or stopping its supply of cooling water.
A part of the invention relates to the means employed for operating the cooling
water-supply pump of the compressor and it consists in the combination with an
air compressor and the water supply pump therefor, of a lever adapted to swing
in a horizontal plane, fulcrumed at one side of the piston rod of the compressor
to one of the cross-head guides, and connected on the other side of the piston rod,
with the crosshead or other reciprocating part of the compressor and a rod for
working the pump connected with the said lever between its fulcrum and the
piston rod, the said levér being preferably arranged between and below the tops
of the crosshead guides.
Inlet valves for air compressors have been commonly constructed with a central
solid stem rigidly attached to or formed with the head of the valve and working
in a guide in the valve seat or casing, but such a construction is objectionable
because of the obstruction which the stem and guide offer to the free passage of
air through the seat or casing, and because of the liability of the head of the valve
to be broken off or to become detached from the stem. With a view of overcoming
the aforesaid objections one part of this invention consists in an inlet valve for an
air compressor, composed of a hollow cylinder or sleeve and a head connected
therewith by a skeleton bridge and having an annular opening between the said
cylinder or sleeve and the head. This part of the invention also consists in the
combination with an inlet valve consisting of a hollow cylinder or sleeve and
a head connected therewith by a skeleton bridge, and a fixed or integral flange at
the end opposite the head and having an annular opening between the said

page_text: cylinder or sleeve and the head, of an axially divided valve seat or casing in which
the cylinder or sleeve works and preferably also a closing spring surrounding the
said cylinder or sleeve and bearing at one end against the flange thereon and at
the other end against the valve casing. In lieu of the fixed or integral flange
on the cylinder or sleeve the latter might be provided with a nut screwed thereon
and forming a bearing for one end of the closing spring, but when the seat or
casing is divided axially such nut is unnecessary as the cylinder or sleeve does
not have to be passed endwise through the seat or casing in placing it in
position.
The invention also consists in the combination with the air chamber or chest for
containing the discharge or outlet valves of a compressor, of a valve casing
consisting of a hollow cylinder and a seat-ring or ring forming the seat, connected
with the cylinder by wings or ribs so as to leave an annular space between them,
and a cap for the casing, all supported in openings in the inner and outer walls of
the said air chamber or chest, a bonnet closing the opening in the said outer wall
and a screw passing through the bonnet and bearing against the cap of the valve
casing so as to hold the latter in proper position.
The invention also consists in the combination with a hollow cylindric discharge
or outlet valve for an air compressor, of a closing spring arranged within the valve
and guided externally by the interior of a guide or bushing placed in the valve.
The invention also consists in the combination with a hollow cylindric discharge
valve of an air compressor and a casing containing a seat for the valve and
provided with a cap or cover, of a spiral spring arranged within the said valve
and having its ends fitted to bearings in the said valve and cap or cover, and a
bushing inserted in the said valve and serving as a guide to the exterior of the
spring.
In air compressors driven by belt or other gearing and not by direct action from
the operating engine we propose to check or stop the compression when the
pressure of the air in the receiver reaches the maximum desired, by holding open
the suction or inlet valve of the compressor so that air taken in through the said
valve will be forced back or returned through it in an uncompressed state;
and one
part of this invention relates to means of producing and regulating such action of
the inlet valve. This part of the invention consists in the combination with the
suction or inlet valve for an air compressor, of a cylinder, a plunger or piston
fitting therein, and adapted to be acted upon by compressed air in or from the
receiver, and serving by its movement to open and hold open the said valve, and a
spring for resisting the action of the said plunger or piston and controlling its
movement to open the valve. This part of the invention also consists in the
combination with the suction or inlet valve and its stem, of a guide for the stem
provided at the outer end with an enlarged head, a casing screwed or otherwise
secured upon the said head and comprising two cylinders of different diameters, a
plunger fitting the cylinder of smaller size and having an attached head fitting the
cylinder of larger size and a spring arranged between the two said heads and
serving to resist and control the movement of the plunger or piston produced by
compressed air and serving to open the valve. This part of the invention further
consists in the combination with the foregoing, of a collar provided with a nipple
for the attachment of an air pipe, surrounding and communicating with the interior
of the cylinder, so that the cylinder may be turned in the collar while its interior
is constantly in communication with the said air pipe.
The improvements in engines for operating air compressors embrace the journal
boxes of such engines and the same improvement in journal boxes are applicable to
journal boxes for other engines and other machinery. In carrying out these
improvements in journal boxes the brasses or linings of the said boxes are made up
of top, bottom and side sections, and the object of the said improvement is to
provide a convenient means for readily adjusting the side sections as they become
loosened by wear or otherwise. To this end one improvement consists in the

page_text: combination in a journal box, of brasses or linings made up of top, bottom and
side sections, hollow or tubular bolts for holding down and adjusting the cap,
wedges for adjusting the side sections, and screws, working through the said
hollow tubular bolts, and serving to adjust or force down the said wedges to
tighten the side sections of the brasses or linings and another improvement
consists in the combination with the aforesaid side sections, hollow or tubular
holding bolts, wedges, and screws for forcing down the wedges, of springs placed
below the wedges for raising the wedges when the said screws are relaxed.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Charles William Potter in the Patent Office on the 8th April
1884.
CHARLES WILLIAM POTTER, of Maida Hill, in the county of Middlesex
"IMPROVEMENTS IN AIR-COMPRESSORS AND ENGINES FOR OPERATING THE SAME,
PARTLY APPLICABLE TO OTHER PURPOSES
"
These improvements in air-compressors chiefly relate to those air compressors
which are operated directly by steam engines, but certain features of the invention
are applicable to compressors operated by belts or gearing.
One part of the invention relates to means of stopping the action of the
compressor without stopping its motion or the motion of the engine which drives
it, when the pressure of air in the receiver to which the compressor delivers the
compressed air exceeds a certain degree.
According to this part of the invention the compression is suspended partly or
wholly by opening communication between the ends of the compressor cylinder, so
that the whole or part of the air will be circulated back and forth from end to end
of the cylinder without being discharged into the receiver. This part of the
invention consists in the combination with the cylinder of a double-acting air
compressor, of pipes or conduits connecting the two ends of the cylinder and a
pressure regulator adapted to be operated by an excess of air pressure in the
receiver, for the purpose of so controlling communication between the ends of the
cylinder through the said pipes or conduits as to allow the circulation of air from
end to end of the cylinder through the said pipes or conduits and so stop the
compressing action when the pressure exceeds the desired degree. This regulator
may consist of a cylinder, a piston, and a valve connected with the said piston; or
of a cylinder and a piston which is itself a valve. This part of the invention
further consists in the combination with the cylinder of a double-acting compressor
provided with pipes or conduits for connecting its ends, and a pressure regulator
for controlling communication between the ends of the said cylinder through the
said pipes or conduits, as above mentioned, of an engine for operating the said
compressor provided with a throttle valve, and connections through which the said

page_text: pressure regulator effects the closing of the throttle valve when it places the ends
of the compressor cylinder in communication and the opening of the said throttle
valve when it shuts off communication between the ends of the said cylinder.
By this means any unnecessary consumption of steam, when the compressor is
not performing any work by pumping air into the receiver is prevented.
In air compressors the cooling water is sometimes discharged directly into the
compressor cylinder by means of a pump worked by the compressor or its
operating engine and when the air is circulated back and forth from end to end of
the compressor cylinder, as herein before described it is necessary to diminish or
stop entirely the discharge from the water pump into the cylinder. To this end
one part of the invention consists in the combination with the compressor cylinder
and its pipes or conduits and pressure regulator for controlling communication
between the ends of the said cylinder as herein before described of a water supply
pump, and a valve which is so connected with the said pressure regulator that when
the latter operates to place the ends of the cylinder in communication through the
said pipes or conduits, it will also operate the said valve to admit air to the suction
pipe of the said pump, for the purpose of diminishing or cutting off entirely the
discharge of water by the pump.
The invention also consists in the combination of the compression cylinder
provided with pipes or conduits and a pressure regulator whereby the ends of the
cylinder will be placed in communication when desired, as herein before described,
a pump for the supply of cooling water to the said cylinder, having an air inlet
valve in its suction pipe, and connections between the said regulator and the
throttle valve of the engine which works the compressor and between the said
regulator and the said air valve, whereby the operation of the pressure regulator
by an excess of air pressure will simultaneously place the ends of the compressor
cylinder in communication, close or partly close the throttle valve of the engine
and open the air inlet valve to admit more or less air to the suction of the pump
for the purpose of diminishing or stopping its supply of cooling water.
A part of the invention relates to the means employed for operating the cooling
water-supply pump of the compressor and it consists in the combination with an
air compressor and the water supply pump therefor of a lever adapted to swing in
a horizontal plane, fulcrumed at one side of the piston rod of the compressor to one
of the cross-head guides, and connected on the other side of the piston rod, with
the cross-head or other reciprocating part of the compressor, and a rod for working
the pump connected with the said lever between its fulcrum and the piston rod,
the said lever being preferably arranged between and below the tops of the
cross-head guides.
Inlet valves for air compressors have been commonly constructed with a
central solid stem rigidly attached to or formed with the head of the valve and
working in a guide in the valve seat or casing, but such a construction is
objectionable because of the obstruction which the stem and guide offer to the free
passage of air through the seat or casing and because of the liability of the head of
the valve to be broken off or to become detached from the stem. With a view of
over-coming the aforesaid objections one part of this invention consists in an inlet
valve for an air compressor, composed of a hollow cylinder or sleeve and a head
connected therewith by a skeleton bridge and having an annular opening between
the said cylinder or sleeve and the head. This part of the invention also consists
in the combination with an inlet valve consisting of a hollow cylinder or sleeve
and a head connected therewith by a skeleton bridge, and a fixed or integral flange
at the end opposite the head, and having an annular opening between the said
cylinder or sleeve and the head of an axially divided valve seat or casing in which
the cylinder or sleeve works; and preferably also a closing spring surrounding the
said cylinder or sleeve and bearing at one end against the flange thereon and at the
other end against the valve casing. In lieu of the fixed or integral flange on the
cylinder or sleeve the latter might be provided with a nut screwed thereon and
forming a bearing for one end of the closing spring, but when the seat or casing is

page_text: divided axially such nut is unnecessary, as the cylinder or sleeve does not have to
be passed end wise through the seat or casing in placing it in position.
The invention also consists in the combination with the air chamber or chest for
containing the discharge or outlet valves of a compressor of a valve casing
consisting of a hollow cylinder and a seat-ring or ring forming the seat, connected
with the cylinder by wings or ribs so as to leave an annular space between them,
and a cap for the casing, all supported in openings in the inner and outer walls of
the said air chamber or chest a bonnet closing the opening in the said outer wall
and a screw passing through the bonnet and bearing against the cap of the valve
casing so as to hold the latter in proper position.
The invention also consists in the combination with a hollow cylindrical
discharge or outlet valve for an air compressor, of a closing spring arranged within
the valve and guided externally by the interior of a guide or bushing placed in the
valve.
The invention also consists in the combination with a hollow cylindrical
discharge valve of an air compressor, and a casing containing a seat for the valve
and provided with a cap or cover of a spiral spring arranged within the said valve
and having its ends fitted to bearings in the said valve and cap or cover, and a
bushing inserted in the said valve and serving as a guide to the exterior of the
spring.
In air compressors driven by belt or other gearing and not by direct action from
the operating engine we propose to check or stop the compression when the
pressure of the air in the receiver reaches the maximum desired, by holding open
the suction or inlet valve of the compressor so that air taken in through the said
valve will be forced back or returned through it in an uncompressed state; and
one part of this invention relates to means of producing and regulating such action
of the inlet valve. This part of the invention consists in the combination with
the suction or inlet valve for an air compressor, of a cylinder, a plunger or piston
fitting therein, and adapted to be acted upon by compressed air in or from the
receiver and serving by its movement to open and hold open the said valve and a
spring for resisting the action of the said plunger or piston and controlling its
movement to open the valve.
This part of the invention also consists in the combination with the suction
or inlet valve and its stem, of a guide for the Stem provided at the outer end
with an enlarged head, a casing screwed or otherwise secured upon the said
head and comprising two cylinders of different diameters, a plunger fitting
the cylinder of smaller size and having an attached head fitting the cylinder
of larger size and a spring arranged between the two said heads and serving"
to resist and control the movement of the plunger or piston produced by com-
pressed air and serving to open the valve: This part of the invention further
consists in the combination with the foregoing, of a collar provided with a nipple
for the attachment of an air pipe, surrounding and communicating with the interior
of the cylinder, so that the Cylinder may be turned in the Collar while its interior
is constantly in communication with the said air pipe.
The improvements in engines for operating air compressors embrace the journal
boxes of such engines and the same improvements in journal boxes are applicable
to journal boxes for other engines and other machinery. In carrying out these
improvements in journal boxes the brasses or linings of the said boxes are made
up of top, bottom and side sections, and the object of the said improvement is to
provide a convenient means for readily adjusting the side sections as they become
loosened by wear or otherwise. To this end one improvement consists in the
combination in a journal box of brasses or linings made up of top, bottom and side
sections, hollow or tubular bolts for holding down and adjusting the cap, wedges
for adjusting the side sections, and screws, working through the said hollow
tubular bolts, and serving to adjust or force down the said wedges to tighten the
Bide sections of the brasses or linings; and another improvement consists in the
combination with the aforesaid side sections, hollow or tubular holding bolts,

page_text: wedges and screws for forcing down the wedges, of springs placed below the
wedges for raising the wedges when the said screws are relaxed.
In the accompanying arangings Figure 1 is a side elevation of an air compressor
and its operating engine embodying the invention; Figure 2 is a plan thereof;
Figure 8 is an end elevation thereof; Figure 4 is a partly sectional side elevation,
upon a larger scale, of the air compressor cylinder, pressure regulator and the throttle
valve of the operating engine; Figure 5 is a plan of the air compressor cylinder
and its appurtenances, including the mechanism for operating the water supply
pump, and upon the same scale as Figure 4; Figure 6 is a transverse vertical
section of the air compressor cylinder and appurtenances on the same scale as
Figures 4 and 5; Figures 7, 8 and 9 are respectively a sectional view, a side view
and a plan of the inlet valve and its casing which are employed in the compressor.
Figure 9* is a longitudinal section of the outlet valve and its casing; Figure 10 is
a partly sectional side view of one of the journal boxes of the operating Engine;
and Figure 11 is a central sectional view of an inlet valve and a regulator
connected therewith, so as to hold the said valve open when the pressure of air in
the receiver exceeds the maximum pressure desired.
Similar letters of reference designate corresponding parts in all the figures.
The general arrangement of the several parts of the compressor will best be
understood from Figures 1, 2, and 3 while for the particular construction of the
several parts to which the invention relates reference may be had to the remaining
figures.
"A." designates the bed plate or frame of the compressor, at one end of which
is secured the compressor cylinder B and at the other end of which is the crank
shaft C mounted in journal bearings or boxes C', which will be hereinafter
described.
Between the crank shaft C and the compressor cylinder B is the steam Cylinder D,
also secured to the bed-plate A.
The pistons of the two cylinders B and D are attached to a common piston rod C².
to which is attached a crosshead C³. working in suitable crosshead guides C.
attached to the bed A. At the outer ends of the crosshead C³. are wrist pins a,
which by means of outside connecting rods C., are connected with crank pins a¹,
fixed in fly wheels Co. which are mounted on opposite ends of the crank shaft C, as
best shown in Figure 2.
The compressor Cylinder B has in. its heads discharge chests or chambers B¹ for
compressed air, which communicate with an air trunk or passage B2 on the top of
the cylinder. From the air trunk or passage B³ the compressed air passes by a
pipe B³ to a receiver, not here shown, and from which a number of rock drills or
other machines derive their supply.
The Steam cylinder D is surmounted by a Steam chest D to which steam passes
by a pipe D in which are a stop valve D³ and a throttle valve D*, which may be
of any suitable construction.
The engine here shown has a cut-off slide valve of which D. is the rod, while Do
is the rod of the main valve.
In rear of the crank shaft O is a rock shaft D7 on which are fulcrumed
levers D. D. The upper ends of these levers are connected by rods or links D¹º. D¹¹.
with the valve rods or stems D5, D6, while to the lower ends of the levers are
connected eccentrics D¹ D₁a on the crank shaft C.
Such in general is the construction of the compressor, but any kind of Engine
may be employed for operating the compressor instead of the one here shown.
The particular construction of the journal boxes C is best seen in Figure 10.
The brass or lining of each journal box C¹ is composed of a top section, b, a
bottom section 6' and two side sections 62. C designates the cap, which is held
down by bolts b. and nuts b. and by tightening these nuts the wear of the top
and bottom sections b, b. is taken up and they are tightened upon the shaft C. At
the back of each side Section 6² is a block 6º. having an inclined outer face and

page_text: bearing against said inclined face is a wedge 66 which fits in the cavity b
immediately below. the holding down bolt b³..
Each holding down bolt 63 is bollow or tubular and through each extends a
screw which bears on the wedge be below, The screw 68 is threaded near each
end and the lower thread screws into a corresponding thread in the lower portion
of the holding down bolt b. while the upper thread receives a jam nut 6, By
tightening the screws 68 the wedges 6 are forced down closing the side sections 6%.
on the shaft C but when the said screws are relaxed, the wedges 6º are raised by
springs b. arranged below them and the side sections 6. are loosened on the shaft C.
The means for taking up wear in the side sections 6" is very compact and desirable,
and although wedges and screws have been before used for tightening up the side
sections of journal box brasses, such screws have not heretofore been inserted through
hollow or tubular holding-down bolta.
In the heads of the compressor cylinder below the discharge chests or chambers B¹.
is a number of inlet or suction valves E working in casings E, working in casings E¹.
The construction of these valves and their casings is best shown in Figures 7.8
and 9, but also in Figure 4.
Each valve E consists of a cylinder or sleeve c, and a head or valve proper E
connected with the cylinder or sleeve, c by a skeleton bridge or web c¹, an annular
space being left between the head and cylinder or sleeve c for the passage of air.
At the end of the sleeve, c, opposite the head E is a flange which is rigidly
secured to or formed integral with the cylinder or sleeve.
The casing E¹ has at one end the valve seat and is externally screw threaded
at co. so as to be fixed in the head of the compressor cylinder, it being provided
with a flange c, in which are notches, c', for the engagement of a wrench for
screwing the casing into and out of the head. A closing spring of surrounds the
Cylinder or sleeve c between its flange c³ and the end of the casing El
As clearly shown in Figures 8 and 9 the casing E¹ is made in two halves or
divided axially, the two sections being connected by steady pins . The Cylinder
or sleeve c, does not therefore have to be slipped end wise through the casing E¹,
but the spring c. being in place on the cylinder or sleeve c, the two sections of the
casing are closed on the latter and the casing, having the valve in place within it,
is then screwed into the head of the compressor cylinder B.
An undivided casing might be used with the valve E, but in that case a nut
screwed upon the outer end of the cylinder or sleeve c, would be substituted for the
flange c³.,
In each air chest or chamber B₁. of the compressor cylinder B. is a number of
outlet or discharge valves F working in casings F¹. and the construction of which is
shown only in Figures 4 and 9*.
Each valve consists of a hollow cylinder, closed at one end to form a valve face
and open at the other end. Each casing F consists of a hollow cylinder within
which the valve works, and the casing has combined with it and forming part of
it a seat-ring d, on which the valve seats. The ring is connected with the cylinder
casing by wings or ribs d¹ leaving a 'nearly continuous annular space d, for the
discharge of compressed air when the valve opens. Each casing rests in openings
or bearings d d in the inner and outer walls of the chest or chamber B₁ and it
and its valve may be inserted in place through the opening in the outer wall, said
opening being closed by a bonnet à³..
Each valve casing is closed by a cap or cover do, and the cap or cover is held in
place on the casing and the casing held in place in the chest or chamber 61, by a
screw d, inserted through the bonnet d³, and bearing on the cap or cover de.
The closing of the valve F is effected by a spring d. bearing at its ends on the
cap or cover do, and the closed end of the valve; and in order to guide said spring
externally the valve has a bushing do, within it, the internal diameter of which
is slightly greater than the external diameter of the spring.
The pump for supplying cooling water to the compressor cylinder B will now be
described, it being best shown in Figures 2 and 5.

page_text: The compressor cylinder B is constructed with passages or conduits, e e, leading
from opposite ends thereof towards the middle, as shown in Figure 4 and the
principal purpose of which will be hereinafter described.
G designates a double pump éxtending parallel with the compressor cylinder B
and secured to the side thereof. A suction pipe f. is divided to form two
branches f¹ leading to opposite ends thereof; and ƒ ƒ³. are respectively the suction
and discharge valves for the two ends. From the discharge valves f³ the water is
delivered through passages f* and ports f only one of which is shown in Figure 4,
into the ports e. e. and thence passes to the two ends of the cylinder B.
In the suction pipe f is an air valve f" which when opened, serves to admit air
to the pump and so diminish or entirely suspend the supply of water to the
compressor cylinder B. The purpose of this will be hereinafter described.
G₁ designates the pump plunger or rod which is operated by the following very
simple and desirable means.
To one end of the cross-head guides C there is fulcrumed at f' a lever G³ which
extends horizontally across to the other side of the piston rod C, and is there
connected by a slot and pin connection ƒ ƒ, with the crosshead C³.. This lever is
between and below the tops of the crosshead guides C, and as the piston rod and
cross-head reciprocate the lever is swung in a horizontal plane.
The Lever G might be operated from some other reciprocating part of the
compressor instead of from the cross-head. The pump plunged or rod G is
connected by a rod G³ with the lever G on the same side of the piston rod on
which it is fulcrumed, and hence the pump piston is reciprocated synchronously
with the compressor piston.
The pressure regulator and appurtenances will now be described, they being best
shown in Figures 4 and 6 but also in Figures-1, 2 and 3.
The two conduits or passages e, e, before referred to are connected by a valve
box H, see Figures 4 and 6 in which is a balanced valve g, controlling communi-
cation between the conduits or passages e, e, and therefore between the ends of the
compressor cylinder B.
Above the valve H. g, is the regulator here shown as consisting of a cylinder, g¹,
and a piston, g³, connected by a rod or stem g³. with the valve g. Below the
Piston g, an inlet pipe 9, enters the cylinder and through this pipe the
regulator is in free communication with the receiver for compressed air not here.
shewn.
The regulator piston g might be loaded by springs, but as here shown a lever I
fulcrumed at g³, bears through a push-piece 8, upon the piston, and has suspended
from its free end a rod 9° carrying weights 97.
When the air in the receiver reaches or exceeds the maximum pressure desired,
and for which the lever I is loaded, the piston will be raised and will open the
valve g so as to place the two ends of the cylinder B in communication through the
conduits or passages e. e.
Some or all of the air in the Cylinder B will then simply be circulated back and
forth from one end of the cylinder to the other and compression will be largely or
wholly suspended When the pressure in the receiver falls the regular piston g
descends and closing the valve g, once more cuts off communication between the
ends of the compressor cylinder and the compression of air is resumed. When
compression is partly or wholly suspended little or no cooling water is required in
the cylinder and therefore connections are provided for then opening the air
valve f in the suction of the pump G.
.
As here shown the weight rod go has upon it a toe 98 and when said rod is raised
by the moving regulator piston g³ the said toe acts on the stem 1 of the valve ƒ6 as
shewn in figure 6 and admits air to the pump G When the regulator ceases to
act the valve fe is automatically closed and the delivery of water into the
compression Cylinder B is resumed. The lever I in its rising and falling moves in
a guide I*.
As the work is largely taken off the engine when compression is suspended
'

page_text: it is advisable to partly close the throttle valve D' to prevent an unnecessary
consumption of steam-The throttle valve D' here shewn is nearly balanced but
the unbalanced pressure will tend to hold the valve open-The connections here
represented consist of a lever I' fulcrumed at gº, and connected by a rod I³ with a
bell crank lever I', which is fulcrumed at g¹º, and one arm of which rests upon the
lever I, When the regulator piston gå raises the lever I it also acts upon the bell
crank lever I' and through the rod 12 and lever I the valve D* is pushed in entirely or
partly closed. By this means the supply of steam to the operating engine is largely
diminished or cut off entirely, when compression is partly or wholly suspended.
Other forms of connections may be used between the pressure regulator and the
engine throttle valve, with substantially the result hereinbefore described―The
pressure regulator shewn in Figure 11 is more particularly adapted for a compressor
operated by a belt or other gearing, but may if desired be used in connection with
a compressor operated directly by an engine.
By this regulator the suction or inlet valve to which it is applied may be held
open so that the air drawn into the compressor cylinder will be again expelled
through the suction valve.
Referring now to figure 11, J designates the valve seat and casing which may
have an external screw thread, h, whereby it may be secured in the head of the
compressor cylinder or in a compressor piston. K designates the valve and K¹ the
valve stem which fits a guide, h¹, formed in the casing J.
Upon the outer end of the guide, h, is formed or rigidly attached a head J¹ and
upon this is screwed a cylinder L, which may be adjusted by turning it and a
lock-nut J' for holding it in place after adjustment.
The cylinder L constitutes a spring case and has formed integral with it a
smaller cylinder L'.
Upon the exterior of the smaller cylinder L' is fitted a collar h³, which is secured
in place thereon between a shoulder, i, and a nut, ¹, so that it may be turned, or
rather so that the cylinder may be turned within the collar.
Upon the collar, h³, is formed a nipple or socket, h³, in which may be screwed an
air pipe, h, which is connected with the compressed air receiver, not here shown,
and air entering the collar through said pipe h*, passes into an annular groove or
channel,, here shown as formed in the exterior of the Cylinder L', and thence
passes through a hole or aperture ³, into the cylinder L¹
L' designates a head which fits, not necessarily tightly, in the Cylinder L and
attached to or formed integral therewith is a plunger or piston L' fitting tightly in
the cylinder L³.
This plunger or piston may be provided with a cup leather packing, j, held in
place by a ring 7, and a screw, 73, or may be provided with any other suitable
packing.
The pressure of air in the cylinder L' tends to move the plunger L³ and head L³,
towards the left, but between the heads J and L² is arranged a spiral spring M,
which resists such movement until the pressure exceeds a predetermined limit,
when it will overcome the resistance of said spring and compress it, the head and
plunger L' L' moving towards the left.
The tension of the spring M may be varied by turning the casing L in or out on
the head J' and locking it by the jam-nut J³, and the heads J¹ L' are cup-shaped or
concave so as to form seats or recesses for holding and properly centering the
Spring M.
Upon the outer end of the valve stem K' is screwed a nut j³, and between this
nut and the head J' is placed the usual spiral closing spring which is centered
and held in place by a groove in the face of the nut and a groove or socket 7 in
the head J¹.
So long as the pressure in the receiver does not exceed the maximum pressure
desired the valve K will operate like an ordinary suction or inlet valve, but as soon
as the maximum pressure is exceeded-the head L³ comes in contact with the end of

page_text: the stem K¹ and acting thereon opens and holds open the valve so that there can
be no compression. As the pressure in the receiver falls to the desired point the
spring M forces back the head and plunger L³ L³, and the valve K resumes its
normal functions as a suction or inlet valve.
It will be seen from the foregoing that not only does this invention provide in a
very simple manner for regulating the compression of air by means of the pressure
of compressed air in the receiver, but that the consumption of steam by the
operating engine and the supply of cooling water to the compressor cylinder are
both regulated correspondingly to the rate of compression and by means of the
same pressure regulator.
The invention is not confined to a pressure regulator of any particular
construction nor to any particular kind of valve for establishing communication
between the ends of the compressor cylinder, nor to any particular system or
combination of connecting devices between the pressure regulator, the air valve
of the pump and the throttle valve of the Engine.
Having thus described the invention what is claimed and desired to be secured
by Letters Patent is :--
Firstly The combination with the Cylinder of a double-acting air compressor, of
pipes or conduits connecting the ends thereof and a pressure regulator, capable of
operation by an excess of air pressure, and serving to control communication
between the ends of said Cylinder through said pipes or conduits, substantially as
described and for the purpose set forth.
Secondly. The combination with the cylinder of a double-acting air compressor,
provided with pipes or conduits for connecting its ends and a pressure regulator
capable of operation by an excess of air pressure, for controlling communication
between the ends of the cylinder through said pipes or conduits, of an operating
engine provided with a throttle valve, and connections through which the said
regulator effects the closing or partial closing of said throttle valve when it places
the ends of the cylinder in communication substantially as described and for the
purpose set forth.
Thirdly:-The combination with the Cylinder of a double acting air compressor,
provided with pipes or conduits connecting its ends and a pump for supplying
cooling water to the Cylinder, of a pressure regulator capable of operation by an
excess of air pressure to place the ends of the cylinder in communication through
Baid pipes or conduits and a valve which is capable of operation by the regulator
at the same time and which serves to admit air to the suction of the pump,
substantially as described and for the purpose set forth.
Fourthly-The combination with the cylinder of a double acting air compressor
provided with conduits connecting its ends, and a pressure regulator capable of
operation by an excess of air pressure to place the ends of the cylinder in
communication through said pipes or conduits of an operating engine for the
compressor provided with a throttle valve, a pump for supplying cooling water to the
compressor cylinder provided with an air inlet valve in its suction, and connections
through which the said regulator closes or partly closes the throttle valve and
opens the said air valve, when acting to place the ends of said Cylinder in
communication with each other, substantially as described and for the purpose set
forth.
Fifthly The combination with an air compressor and a water supply pipe
therefor, of a lever arranged to swing in a horizontal plane, fulcrumed at one side
of the piston rod of the compressor to one of the crosshead guides and connected
on the other side of the piston rod, with the crosshead or other reciprocating part
of the compressor and a rod for working the pump connected with said lever
between its fulcrum and the piston rod, substantially as described and shewn with
reference to Figures 2 and 5 of the Drawing.
Sixthly The inlet valve herein shown and described for an air compressor,
consisting of a hollow cylinder or sleeve and a head connected therewith by a.

page_text: skeleton bridge and having an annular opening between said Cylinder or sleeve and
said head, substantially as described and for the purpose set forth.
Seventhly The combination with an inlet valve for an air compressor, consisting
of a hollow cylinder or sleeve having a head connected therewith by a skeleton
bridge, and a fixed or integral flange at the end opposite the head, and also having
an annular opening between the sleeve and head of an axially divided valve seat
or casing in which said cylinder or sleeve works, substantially as shewn and
described with reference to Figures 7. 8 and 9 of the drawing.
Eighthly The combination of the inlet valve consisting of the cylinder or sleeve c
and head E connected by the skeleton bridge c¹, and having the annular space c
and the fixed or integral flange c³, the axially divided casing E', in which said
cylinder or sleeve works and the closing spring c³, substantially as shown and
described with reference to figures 7. 8 and 9 of the drawing.
Ninthly. The combination with the air chest or chamber for containing the
discharge or outlet valves of a compressor, of a valve casing consisting of a hollow
cylinder and a seat-ring connecting with the cylinder by wings or ribs so as to
leave an annular space between them, and a cap for the casing, all being supported
in openings in the inner and outer walls of the air chest or chamber, a bonnet for
closing the opening in said outer wall, and a screw passing through the bonnet
and bearing against the cap of the valve casing, substantially as shown and
described with reference to figures 4 and 9* of the drawing.
Tenthly -The combination with a hollow cylindrical discharge or outlet valve for
an air compressor, of a closing spring arranged within the valve and guided
externally by the interior of a guide or bushing placed in the valve substantially
as shown and described with reference to Figures 4 and 9 of the drawing.
Eleventhly-The combination with a hollow cylindrical discharge or outlet valve
for an air compressor and a casing containing a seat for the valve, and provided
with a cap or cover of a spiral spring arranged within the valve and having its
ends fitted to bearings in the valve and in the cap or cover of the casing, and a
bushing inserted in said valve and serving as a guide to the exterior of the
spring, substantially as shown and described with reference to Figures 4 and 9* of
the drawing.
Twelfthly The combination with the suction or inlet valve for an air compressor,
of a cylinder, a plunger or piston fitting therein and adapted to be acted on by
compressed air, and serving by its movement to open and hold open said valve,
and a spring for resisting and controlling said plunger or piston in its movement
to open the valve, substantially as shewn and described with reference to figure 11
of the drawing.
Thirteenthly:The combination with the suction or inlet valve of an air
compressor and its stem, of a guide for the stem provided at the outer end with
an enlarged head, a casing screwed or otherwise secured upon said head and
comprising two cylinders of different diameters, a plunger fitting the cylinder of
smaller size and having an attached head fitting the cylinder of larger size, and a
spring arranged between the two heads and serving to resist and control the
movement of the plunger which is produced by compressed air and which serves to
open said valve, substantially as described and shown with reference to Figure 11
of the drawing.
Fourteenthly The combination with the suction or inlet valve K and its stem K¹
of a guide, h¹ and its head J¹, the casing comprising the Cylinders L. L' and
screwed upon said head J', the connected head and plunger L, L³, the spring M,
and the collar, h², provided with the air inlet, h, and in which said cylinder L'
may turn while the interior of the cylinder is constantly in communication with
said air inlet, substantially as described and shown with reference to Figure 11 of
the drawing.
Fifteenthly The combination in a journal box for air compressor engines and
other purposes, of brasses or linings made up of top, bottom and side sections,
hollow or tubular bolts for holding down and adjusting the cap, wedges for

page_text: adjusting the said side sections and screws working through said hollow or
tubular bolts for adjusting the wedges to tighten the said side sections, substan-
tially as described and for the purpose set forth.
Sixteenthly-The combination in a journal box for air compressor engines and
other purposes of brasses or linings made up of top, bottom and side sections,
hollow or tubular bolts for holding down and adjusting the cap, wedges for
tightening said side sections, screws working through said hollow or tubular bolts
for adjusting said wedges to tighten said side sections and springs acting upon the
wedges to loosen them when the said screws are relaxed, substantially as described
and for the purpose set forth.
In Witness whereof I the said Charles William Potter have hereto set my hand
and seal this eighth day of April in the year of our Lord one thousand eight
bundred and eighty four