IMPROVEMENTS IN DIRECT- ACTING STEAM ENGINES FOR PUMPING AND OTHER PURPOSES
Year: 1877

page_text: LETTERS PATENT to Bristow Hunt, of Serle Street, Lincoln's Inn, in the County
of Middlesex, Gentleman, for the Invention of "IMPROVEMENTS IN DIRECT-
ACTING STEAM ENGINES FOR PUMPING AND OTHER PURPOSES" A communication
from abroad by John Burger Waing, of Stamford, County of Faufield, State
of Connecticut, and Joseph Beinaid Wilson, of Philadelphia, Pennsylvania,
United States of America
Sealed the 17th July 1877, and dated the 27th January 1877.
PROVISIONAL SPECIFICATION left by the said Bristow Hunt at the Office
of the Commissioners of Patents on the 27th January 1877
"
BRISTOW HUNT, of Seile Street, Lincoln's Inn, in the County of Middlesex,
Gentleman IMPROVEMENTS IN DIRECT-ACTING STEAM ENGINES FOR PUMPING
AND OTHER PURPOSES " A communication from abroad by John Burger Waring,
of Stamford, County of Fairfield, State of Connecticut, and Joseph Bernard Wilson,
of Philadelphia, Pennsylvania, United States of America
The object of this Invention is to construct a simple and economical direct-action
steam engine, the valve of which shall be automatically operated by the steam
alone, without the aid of external appliances usually employed for operating the
valves of engines of this class.
The main piston which fits snugly to the interior of the main cylinder is composed
of three united sections, being reduced in diameter at two places, so as to form with
the cylinder two annular chambers or passages, as described herein-after On the
top of the cylinder is a cylindrical valve chest containing a cylindrical valve, also
composed of three sections fitting snugly in the chest and reduced in diameter at
two points, so as to form with the said chest two annular chambers or passages At
the lower end of the valve is a piston adapted to the interior of the main cylinder,
this piston and the valve being connected together by a 1od, part of which is less in
diameter than the opening in the top of the cylinder through which the said rod
passes, for a purpose explained herein-after A 1od or plunger depending from the
main piston passes through a stufhing box at the bottom of the cylinder.

page_text: There are
number of channels or passages which will be referied to in the
following description of the operation of the engine
It may be stated in the outset that there are two inlets for live steam, that one
annular chamber of the main piston and one annular chamber of the piston valve
are always exposed to the live steam, that there is a communication between this
annular chamber of-the-piston valve and the space above the valve, on which there
18 consequently a constant live steam pressure, and that there are three outlets for
the exhaust steam
Supposing the main piston to have reached or nearly reached the limit of its
upward movement, live steam from the annular steam chamber of the main piston
having passed through a channel (1) in the cylinder to the space above the piston,
and the pressure of this steam having foiced the upper piston and its valve upwards,
and the steain above the upper piston having escaped through another channel (2)
in the cylinder into the annular exhaust chamber of the main piston, and thence
through the outlet in communication therewith The piston now commences to
descend, owing to the pressure of steam from the channel (1), which is comparatively
small, so that the commencement of the downward movement of the piston is slow
and free from sudden shocks It should here be understood that while the piston
descends the steam below it is being exhausted through a chamber or passage (3) in
the cylinder through the valve chest below its valve, and thence through the outlet
or exhaust passage in communication therewith
As the main piston descends it closes the passage (1), but before the latter is quite
closed the piston exposes a port (5) communicating with the upper steam inlet
through a channel (4) in the cylinder, and through the annular steam chamber of
the piston valve, so that the piston continues its descent under a full head of live
steam
When the piston has reached its lowest position the exhaust port in communication
with its annular exhaust chamber has been closed and the channel (2) has formed a
communication between the piston's annular steam chaunber and the space above the
valve piston, the consequence of which is that the piston valve suddenly descends
By this movement the annulai stenm chamber of the valve is made to communicate
with the upper steam inlet, and also with the channel (3) through which the live
steam passes to, the space beneath the main piston At the same tune theic is
an open communication through the port (5), passage (4), and annulai, exhaust
chamber of the valve between the uppermost exhaust outlet and the space above
the main piston, the consequence of which is that the piston 11ses in its return
movement
Turning back to the anival of the main piston at its lowest position, and to the
downward movement of the valve and its piston, it will be understood that the
latter in its descent is acting against steam above the main piston, this, however,
1s not sufficient to prevent the downward movement of the valve, for there is the
pressure of live steam above the valve piston, plus the pressure of live steam on the
top of the valve, and the combined areas of the two exceed the area of the main
piston
The main piston continues its upward movement until it uncovers the lower port
of the channel 1, when the live steam from the annulai steam chainber of the main
piston gains access to the space above the piston, then the under side of the valve
piston is exposed to the full pressure of live steam, and is only opposed by the
pressure of steam on the lesser area of the valve, and as the main piston is supported
below by a pressure of steam on an annular surface of greater area than that of
the valve the instant rising of the said valve and its piston takes place, after which
there is a repetition of the above-described movements
.
As before remarked a portion of the iod which connects the valve with its piston
is somewhat less in diameter than the hole in the top of the cylinder through which
the rod passes, in other words there is an annular space around a portion of the 10d.
through which space the steam above this piston can escape to the outlet in com-

page_text: munication therewith during the rapid upward movement of the said piston, the
lower portion of the rod, however, is arranged to fit snugly in the hole in the top of
the cylinder, so that a small quantity of steam may be trapped between the piston
and cylinder cover, to serve as a cushion for the former
It will be seen without further description that a reciprocating motion is imparted
to the main piston without the usual valve operating appliances common to other
direct-action engines, and that the engine may be used in connection with a pump,
oi may form part of a steam hammer, or of a rock-drilling machine, or other machines
of like character
It will also be evident to those familiar with engines of this class that the
passages and ports may be arranged in different ways without departing from the
main features of the Invention
The annular exhaust chamber of the main piston, and the outlet in communication
therewith, may be dispensed with, but the use of them is preferred
An important feature of the Invention is the arrangement of the valve chest at
the top of and in line with the cylinder, a plan which facilitates construction, for
1 casons well known to those practically familiar with the construction of steam
engines
In using the engine for pumping purposes, to which it will in most cases be
applied, it may be combined with a pump in the following manner -The body of
the pump which has the usual inlet, outlet, and chamber, and is furnished with
conical or other usual valves not needing description, may form the base of the
engine. On the lower cover of the steam cylinder is situated a stuffing box for the
plunger depending from the main piston The follower of this stuffing box consists
of a tube continued downwards into or nearly into the said chamber of the pump
through another stuffing box, the follower of which consists of a simple ring
surrounding the said tube, on a portion of which latter a screw thread is formed for
a nut, on sciewing which downwards the follower ring is depressed and the tube
elevated, so that equal amount of pressure will be imparted to the packing in both
of the stuffing boxes By this arrangement the plunger of the piston is entirely
inclosed, and protected from dust and dirt
It will be understood that proper provision is made for lubricating the interior of
the tube.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Bristow Hunt in the Great Seal Patent Office on the 27th July
1877.
•
BRISTOW HUNT, of Serle Street, Lincoln's Inn, in the County of Middlesex,
Gentleman. "IMPROVEMENTS IN DIRECT-ACTING STEAM ENGINES FOR PUMPING
AND OTHER PURPOSES" A communication from abroad by John Burger Waring, of
Stamford, County of Fairfield, State of Connecticut, and Joseph Bernard Wilson, of
Philadelphia, Pennsylvania, United States of America.
The object of this Invention is to construct a simple and economical direct-action
steam engine, the valve of which shall be automatically operated by the steam alone,
without the aid of external appliances usually employed for operating the valves of
engines of this class
On the accompanying Drawings Figures 1, 2, and 3 represent vertical sections of
the engine, showing the operating parts in different positions.
The main piston B which fits snugly to the interior of the main cylinder A
is composed of three united sections a, a, a, being reduced in diameter at two
places, so as to form with the cylinder two annular chambers or passages m, n, as
described herein-after On the top of the cylinder A is a cylindrical valve chest
containing a cylindrical valve E, also composed of three sections e, e¹, e¹¹, fitting

page_text: snugly in the chest and reduced in diameter at two points, so as to form with the
said chest two annulai chambers or passages x, Y At the lower end of the valve is
a piston G adapted to the interior of the main cylinder, this piston and the valve
being connected together by a rod f, part of which is less in diameter than the
opening in the top of the cylinder though which the said od passes, for a purpose
explained herein-after A-1od or-plunger II attached to or forming part of the main
piston passes through a stuffing box at the bottom of the cylinder
There are a number of channels or passages which will be referred to in tho
following description of the operation of the engine
It may be stated in the outset that there are two inlets 2, 3, for live steam, that
the ammula chamber m of the main piston and the annulai chamber y of the piston
valve are always exposed to the live steam, that there is a communication t, shown
by dotted lines, between the annular chamber y and the space above the piston
valve, on which there is consequently a constant live steam pressure, and that there
are three outlets k, l, k¹¹, for the exhaust steam
Supposing the main piston to have reached or nearly reached the Innit of its
upward movement, as shown in Figure 1, live steam from the annulai chamber m
having passed through a channel in the cylinder to the space above the piston, and
the pressure of this steam having forced the piston G and its valve E upwards to
the position shown, and the steam above the piston G having escaped through
another channel p in the cylinder into the annulai exhaust chamber n of the
piston B, and thence through the outlet " in communication therewith The piston
now commences to descend, owing to the pressure of steam from the channel L,
which is comparatively small, so that the commencement of the downward move-
ment of the piston is slow and free fiom sudden shocks It should hele be
understood that while the piston descends the steam below it is being exhausted
though a channel or passage w in the cylinder through the valve chest D below its
piston valve, and thence through the outlet or exhaust passage k¹ in communication
therewith
As the main piston descends it closes the passage 1, but before the latter is quite
closed the piston exposes a port v comiuunicating with the steam inlet 1 through a
channel M in the cylinder, and through the annular steam chamber y, so that the
piston continues its descent under a full head of live stcom
When the piston B has reached its lowest position, Figure 3, the exhaust port Z¹i
in communication with its annular exhaust chamber has been closed, and the
channel p has formed a communication between the annulai steam chamber m and
the space 'above the valve piston G, the consequence of which is that the piston.
valve suddenly descends By this movement the annular steam chamber y of the
valve is made to communicate with the steam inlet 3, and also with the channel w,
through which the live steam passes to the space beneath the main piston
same time there is an open communication through the port v, passage M, and
annular exhaust chamber a of the valve, between the exhaust outlet % and the space
above the piston B, the consequence of which is that the piston 11ses in its return
movement
At the
Reverting to the anival of the main piston at its lowest position, Figure 3, and
to the downward movement of the valve and its piston, it will be understood that
the latter in its descent 15 acting against steam above the main piston, this, however,
18 not sufficient to prevent the downward movement of the valve, for there is the
pressure of live steam above the piston G, plus the pressure of live steam on the
top of the valve, and the combined areas of the two exceed the area of the main
piston
The main piston continues its upward movement until it uncovers the lower port
of the channel l, when the live steam from the chainbei m gains access to the space
above the piston B, when the under side of the valve piston G is exposed to the full
pressure of live steam, and is only opposed by the pressure of steain on the lesser
area of the valve, and as the main piston is supported below by a pressure of steam

page_text: on an annular surface of greater area than that of the valve, the instant rising of
the said valve and its piston takes place, after which there is a repetition of the
above-described movements
As before remarked a portion of the rod f which connects the valve with its
piston G is somewhat less in diameter than the hole in the top of the cylinder
through which the 1od passes, in other words there is an annular space around a
portion of the rod, through which space the steam above the piston G can escape to
the outlet during the rapid upward movement of the said piston The lower
portion of the rod f, however, is arranged to fit snugly in the hole in the top of the
cylinder, so that a small quantity of steam may be trapped between the piston and
the cylinder cover, to serve as a cushion for the formei
It will be seen without further description that a reciprocating motion is imparted
to the main piston without the usual valve-operating appliances common to other
direct-action ongines, and that the engine may be used in connection with a pump,
or may form part of a steam hammer, or of a lock-dilling machine, or of other
machines of like character
It will also be evident to those familiar with engines of this class that the
passages and ports may be arranged in different ways without departing from the
main features of the Invention
The chamber n and the outlet kl may be dispensed with, but the use of them is
preferred
An important feature of the Invention is the arrangement of the valve chest at
the top of and in line with the cylinder, a plan which facilitates construction, for
reasons well known to those practically familiar with the construction of steam
ongines
In using the engine for pumping purposes, to which it will in most cases be
applied, the plan, shown in Figure 1, of combining it with a pump is preferi ed.
The body P of the pump, which may form the base of the engine, as shown,
has the usual inlet Q, outlet Q, and chamber R, and 19 furnished with
conical or other usual valves not needing description On the lower cover of the
steam cylinder is situated a stuffing box h for the plunger H depending from the
main piston B The follower of this stuffing box consists of a tube S continued
downwards into or nearly into the chamber R of the pump through another stuffing
box u, the follower of which consists of a simple ing T surrounding the tube S, on
a portion of which latter a screw thread is formed for a nut V, on screwing which
downwards the follower ring T is depressed and the tube S elevated, so that equal
amount of pressure will be imparted to the packing in both of the stuffing boxes u
and By this arrangement the plunger H of the piston B is entirely inclosed and
protected from dust and dirt
It will be understood that proper provision is made for lubricating the interior of
the tube S
Having now described the nature and object of the said Invention, together
with the manner in which the same is to be or may be performed or carried into
practical effect, I would remark in conclusion that I claim as the Invention com-
inumicated to me by the above-named John Burger Wang and Joseph Beinard
Wilson,-
Firstly The combination in a duect-action engine of a main piston B, cylindrical
valve E, and its piston G, with inlets and outlets, and ports, and passages, arranged
substantially as described and for the purpose specified
Secondly An opening in the top of the main cylinder communicating with an
exhaust outlet in combination with the rod f of the valve and its piston, the upper
portion of the said 1od being less than the opening, and the lower portion being
inade to fit the same, all substantially as set forth
Thirdly The combination in a direct-action engine of the main cylinder with
a cylindrical valve chest arranged in line with the said main cylinder, substantially
as set forth,

page_text: And Fourthly The combination of the piston or plunger H, the stuffing box h of
the steam cylinder, the stuffing box u of the pump tube S, and nut V.
In witness whereof, I, the said Bristow Hunt, have hereunto set my hand
and seal, this Twenty-seventh day of July, in the year of our Lord One
thousand eight hundred and seventy-seven.
DPISTOW ITAL
1
BRISTOW HUNT (LS)