IMPROVE- MENTS IN STEAM ENGINES
Year: 1874

page_text: LETTERS PATENT to William M'Naught, the elder, John McNaught,
and William McNaught, the younger, all of Rochdale, in the
County of Lancaster, Engineers, for the Invention of "IMPROVE-
MENTS IN STEAM ENGINES,"
Sealed the 5th February 1875, and dated the 24th September 1874.
PROVISIONAL SPECIFICATION left by the said William McNaught,
the elder, John M'Naught, and William M*Naught, the younger,
at the Office of the Commissioners of Patents, with their Petition,
on the 24th September 1874.
We, WILLIAM MCNAUGHT, the elder, JOHN MCNAUGHT, and WILLIAM
MCNAUGHT, the younger, all of Rochdale, in the County of Lancaster,
Engineers, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN STEAM ENGINES," to be as follows:-
The first part of our Invention relates to improvements in the present
methods of producing an instantaneous cut-off by means of spring
pistons or weights suddenly released, and consists as herein-after
A

page_text: described, that is to say, in employing for this purpose to revolving
cams, one for each end of the cylinders, the form of their peripheries
approximating to that of a geometric spiral of one revolution, or with
one cam with two spirals of half a revolution, having a sudden drop
from its greatest radius to its least, the difference of which radii being
the amount of "lift." As these cams rotate they raise the ends of two
levers in opposition to the force of the aforesaid springs, which suddenly
depress their ends when the drop in the cam arrives. These levers may
be connected to any of the class of valves herein-after described, so that
raising them opens the valve, and the sudden depression shuts it, pro-
ducing the required cut-off; which may be caused to occur earlier or
later in the stroke within a limited range by withdrawing or advancing
those levers lengthwise, either in the direction or contrary to the
direction of the rotation of the cams. Thus withdrawing or advancing
being performed by the governor by usual connections. By employing
two cams, one for each end of the cylinder, we can adjust the amount
of cut-off at either end of the cylinder without interfering with the other
end. In order to increase the range of the said cut-off we drive the
shaft upon which the cams are mounted by a pair of elliptical wheels,
which impart a varying angular velocity to the said shaft, and con-
sequently to the said cams, and those wheels are so geered to the fly
wheel or crank shaft that the cams may have their least angular
velocity when the ends of the said levers are in the vicinity of the drop
on their periphery, by which means a greater range of cut-off is obtained
than by the use of circular wheels.
In order to prevent concussion from the sudden drop we employ an
arrangement of air cylinder having one or more holes in the periphery,
the piston of which after the lever is released passes over the said holes,
the air then becomes confined and its resistance stops the piston, and
consequently the valve to which it is connected. The said holes may be
opened or closed partially by shifting the position of a hoop fitted on
the said cylinder, having holes through its periphery corresponding with
the holes in the cylinder.
The above described method of varying the cut-off may be applied
either to Corliss valves or any description of slide valve, piston valve,
gridiron valve, or rotating disc valve, whether on a stationary surface or
superimposed upon another valve, and either with oval or eccentric or

page_text: circular wheels, and in connection with oval or excentric wheels or the
air cylinder above described.
The second part of our Invention relates to an isochronous governor,
which may be adapted either to an ordinary throttle valve or to the
varying of any cutting-off mechanism. It consists in two or more.
ordinary arms and balls hung from the top of a spindle in the ordinary
way, each arm having a roller mounted on a pin or stud attached
thereto, either above or below the ball. As the balls recede from the
axis of the spindle by virtue of their centrifugal force the said rollers
act on the under side of curved arms or horns attached to a counterpoise
weight, which slides on the said spindle and raises the said weight and
lowers it when the balls approach towards the axis of the said spindle,
the curvature of the said arms or horns being made proportionate to the
increased centrifugal force as the balls move outwards. The counter-
poise weight is connected to the valves in the usual manner.
Other improvements connected with governors coming under the
second head of our Invention relate to a combination of the governor
above described, or any other ordinary or well-known governor, with
hydraulic apparatus for adjusting the throttle valves of a steam engine,
or for acting upon cut-off valves, or arrangements for regulating the
cut-off of the steam, according to the varying speed of, or load upon the
engine; and our improved combination consists in causing the move-
ment of the governor to act upon a balanced valve or valves (we prefer
a piston valve) which will regulate the immission and emission of.
liquid under pressure (derived from a pump, elevated reservoir, boiler,
or other convenient source of pressure) to and from both sides of a
piston in a cylinder as the speed increases or decreases, the rod of such
piston being connected with the mechanism of the valve or cut-off
arrangements to be regulated.
The third part of our Invention relates to and consists in improvements
in valves. Superimposed upon any slide valve we employ another valve
similar to that known as the Corliss, the working surface of which is a
convex portion of a cylinder having a slit or slits similar to those in a
gridiron valve parallel with the axis, with intervening solid spaces which
must be wider than the slits. The slide valve upon which one or two of
these are superimposed has a concave surface corresponding to the
convex surface of the superimposed valve with corresponding slits and
A 2

page_text: spaces, which slits communicate with that end of the valve which
admits the steam into the cylinder. The cut-off is effected by shunting
the spaces aforesaid on the aforesaid cylindrical valve over these slits,
thereby stopping any further supply of steam to the cylinder. For this
purpose we use a spindle adjusted to the axis of the cylinder of which
the valve face is a portion, which spindle passes through a stuffing box
and has a lever keyed upon it which is connected by a link to the lover
described in the first part of our Invention, as being actuated in one
direction by the spiral cam, and in the other direction by the spring or
piston. This superimposed valve may be confined so as not to move
endwise, or it may partake of the endwise motion of the valve upon
which it rests.
Other improvements under this head consists also of a slide valve
having a superimposed valve upon it somewhat similar to that above
described, except that the slits for the steam are not parallel to the axis
of the superimposed valve, but in a diagonal or screw, direction in respect
to such axis, the direction of the slit for one end of the cylinder being
reversed to that for the other end, and the superimposed valve cuts off
the steam by a sliding movement in the direction of its axis, the time of
the cut-off being varied by oscillating the superimposed valve on its
axis (one way to cut off sooner, the other way to cut off later) through
mechanism similar to that above described, which receives movement
by being combined with the hydraulic apparatus herein-before described
under the second head of our Invention, or any other well known
arrangements for regulating cut-off apparatus.
The primary slide valve is actuated by an eccentric in the usual
manner, and the superimposed slide may be actuated by an eccentric,
but we prefer (and this forms one feature of our Invention) to work the
last named valve by a lever or levers in connection with the beam of
beam engines, or some part having reciprocating motion from the piston
of the engine, the movement of the said valve being given at the same
time but in the opposite direction to that of the piston. When the
pressure is great and the stroke is short, as in locomotive and agricutural
engines, we make the said primary valve nearly the length of the
cylinder, which diminishes waste steam in the ports. We arrange the
exhaust port so as to run lengthway of the cylinder instead of crosswise,
by which means we obtain greater wearing surface on the valve and
cylinder facings.

page_text: The fourth part of our Invention which is specially applicable to
locomotive and agricultural engines consists in a method of regulating
the "blast," which we affect by means of a sliding bar passing through
and steadied by the sides of the smoke box in the inside of which
attached to this bar are two, three, or more taper nozzles of various
diameters at the small end, the larger end being the diameter of the
blast pipe. By sliding the bar any one of the nozzles may be brought
over and into contact with the end of the blast pipe. One end of the
bar which protrudes through the sides of the smoke box has rack teeth
into which a pinion is geered, the shaft from which goes to the fire-box
end or any convenient place, and has a handle held by a notch; when
the handle is in this notch one or other of the nozzles is on the blast
pipe, and the diameter of the pinion is so proportioned to the distance
between the nozzles that one revolution thereof shifts the bar the proper
distance, so that any one of the nozzles may be brought over the blast
pipe, thereby varying the draught through the furnace as may be
required.
The fifth part of our Invention relates to piston valves described in
the Specification of Letters Patent dated March Seventh, One thousand
eight hundred and fifty, and Number 12,988, granted to William
M'Naught, senior, and in the Specification of Letters Patent dated
December Twenty-seventh, One thousand cight hundred and fifty-six,
and numbered 3079, granted to the said William M*Naught, and another,
the said piston valve having four or more projections on the steam side
which would cover or uncover a like number of slits through the sides
of the cylindrical shell in which it worked by turning the said piston
valve round its axis, the steam being admitted to and exhausted from
the main cylinder by the usual reciprocating motion of the valve, as
fully described in the Specifications of the said Letters Patent.
Our present improvements consist in making the shell in which the
valve works in two separate pieces, one piece occupying the steam side
of the port, and the other the exhaust side, thus leaving the exhaust side
free from any obstruction. The piece on the steam side of the port has
the slits through which the steam passes in the thickness of metal
instead of opening into a chamber as heretofore, thereby diminishing
waste space betwixt the valve and the cylinder.
Our improvements in the valve itself consists in prolonging the
cylindrical part on the steam side, and adopting slits through it

page_text: corresponding with the slits in the shell instead of projections as hereto-
fore, and thereby obtaining a proportion of wearing surface better
adapted to high pressures than heretofore, not being liable to wear the
shells taper, and secondly, in making the valve more flexible by
employing a horse-shoe spring bearing equally on three equidistant
points of the periphery. The steam slits are opened and closed by
an intermittent rotatory motion in one direction; this is effected by
connecting the levers mentioned under the first head of our Invention to
a lever and ratchet wheel mounted upon a hollow driving spindle which
passes through a stuffing.box on the valve chest, in such a manner that
when the last-mentioned lever rises by the action of the cam it seizes hold
of a fresh tooth of the ratchet wheel, and when the drop occurs the piston
valve is thereby turned on its axis so as to cut off the steam by closing
the slits. The reciprocating motion of the piston valve is communicated
by an eccentric in the usual manner; the rod from the piston is attached
to a swivel on the end of the valve spindle to admit of its being turned
round. This valve spindle passes through the hollow driving spindle
and has two, four, or six, or any number of projections which take into
a like number of grooves in the inside of the hollow spindle; by this
means the hollow spindle turns the valves round intermittently without
interfering with their reciprocating motion. The said hollow driving
spindle has a stuffing box at the outside. end for the valve spindle to
pass through.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William M'Naught, the elder, John M'Naught, 2
and William M*Naught, the younger, in the Great Seal Patent
Office on the 23rd March 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, WILLIAM
MCNAUGHT, the elder, JOHN MCNAUGHT, and WILLIAM M Naught, the
younger, all of Rochdale, in the County of Lancaster, Engineers, send 3
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-fourth day of September, in
the year of our Lord One thousand eight hundred and seventy-four, in
the thirty-eighth year of Her reign, did, for Herself, Her heirs and 3

page_text: successors, give and grant unto us, the said William M'Naught, the
elder, John M'Naught, and William M'Naught, the younger, Her special
license that we, the said William M'Naught, the elder, John M'Naught,
and William M'Naught, the younger, our executors, administrators,
and assigns, or such others as we, the said William M'Naught, the
elder, John McNaught, and William M'Naught, the younger, our
executors, administrators, and assigns, should at any time agree with,
and no others, from time to time and at all times thereafter during
the term therein expressed, should and lawfully might make, use,
exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS IN STEAM ENGINES," upon the condition (amongst others)
that we, the said William M'Naught, the elder, John M'Naught, and
William McNaught, the younger, our executors or administrators, by an
instrument in writing under our, or their, or one of our or their hands and
seals, should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, and
cause the same to be filed in the Great Scal Patent Office within
six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that we, the said William M*Naught, the elder, John
M Naught, and William M'Naught, the younger, do hereby declare the
nature of our said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement and the accompanying Drawings (that is to
say) :—
.
The first part of our Invention relates to improvements upon the
present methods of producing an instantaneous "cut-off" by means of
spring pistons or weights suddenly released, and consists in combining
with cut-off mechanism the combination and arrangement herein-after
described, that is to say, in employing for this purpose two revolving
cams, one for each end of the cylinder, the form of their peripheries
approximating to that of a geometric spiral of one revolution, or with
one cam with two spirals of half a revolution, having a sudden drop
from its greatest radius to its least, the difference of which radii being
the amount of "lift." As these cams rotate they raise the ends of two
levers in opposition to the force of the aforesaid springs, which suddenly
depress their ends when the drop in the cam arrives. These levers may

page_text: be connected to any of the class of valves herein-after described, so that
raising them opens the valve, and the sudden depression shuts it, pro-
ducing the required cut-off, which may be caused to occur earlier or
later in the stroke within a limited range by withdrawing or advancing
tbose levers lengthwise cither in the direction or contrary to the direction
of the rotation of the cams, this withdrawing or advancing being performed
by the governor by usual connections. By employing two cams, one for
each end of the cylinder, we can adjust the amount of "cut-off" at
either end of the cylinder without interfering with the other end. In
order to increase the range of the said cut-off we drive the shaft upon
which the cams are mounted by a pair of elliptical wheels which impart
a varying angular velocity to the said shaft, and consequently to the said
cams, and those wheels are so geered to the fly whcel or crank shaft
that the cams may have their least angular velocity when the ends of
the said levers are in the vicinity of the drop on the periphery of the
cams, by which means a greater range of "cut-off" is obtained than by
the use of circular wheels.
In order to prevent concussion from the sudden drop we employ an
arrangement formerly known as the air cataract, consisting of an air
cylinder having one or more holes in the periphery, the piston of which,
after the lever is released, passes over the said holes; the air then
becomes confined, and its resistance stops the piston, and consequently
the valve to which it is connected. We prefer to open or close the holes
in the cylinder partially by shifting the position of a hoop fitted on the
said cylinder having holes through its periphery corresponding with the
holes in the cylinder.
The above described combination and arrangement of mechanism for
varying the cut-off may be applied either to the "Corliss valve" or any
description of slide valve, piston valve, gridiron valve, or rotating disc
valve, whether on a stationary surface or superimposed upon another
valve, and either with oval, or cccentric, or circular wheels.
The second part of our Invention relates to an isochronous governor,
which may be adapted either to an ordinary throttle valve or to the
varying of any cutting-off mechanism. It consists in two or more
ordinary arms and balls hung from the top of a spindle in the ordinary
way, each arm having a roller mounted on a pin or stud attached thereto,
either above or below the ball. As the balls recede from the axis of the

page_text: spindle by virtue of their centrifugal force the said rollers act on the
under side of curved arms or horns attached to a counterpoise weight,
which slides on the said spindle and raises the said weight and lowers
it, when the balls approach towards the axis of the said spindle the
curvature of the said arms or horns being made proportionate to the
increased centrifugal force as the balls move outwards. The counterpoise
weight is connected to the valves in the usual manner.
Other improvements connected with governors coming under the
second head of our Invention relate to a combination of the governor
above described or any other ordinary or well-known governor with
hydraulic apparatus for adjusting the throttle valve of a steam engine,
or for acting upon "cut-off" valves, or arrangements for regulating the
"cut-off" of the steam, according to the varying speed of or load upon
the engine; and our improved combination consists in causing the
movement of the governor to act upon a balanced valve or valves (we
prefer a piston valve) which will regulate the immission and emission of
liquid under pressure (derived from a pump, elevated reservior, boiler,
or other convenient source of pressure) to and from both sides of a piston
in a cylinder as the speed increases or decreases, the rod of such piston
being connected with the mechanism of the valve or cut-off" arrange.
ment, to be regulated or combined with the governor to act as what is
known as a lengthening and shortening motion.
The third part of our Invention relates to and consists in improve-
ments in valves. Superimposed upon any slide valve we employ another
valve similar to that known as the Corliss, the working surface of which.
is a convex portion of a cylinder having a slit or slits similar to those in
a gridiron valve parallel with the axis with intervening solid spaces,
which must be wider than the slits. The slide valve, upon which one
or two of these are superimposed, has a concave surface corresponding.
to the convex surface of the superimposed valve, with corresponding
slits and spaces, which slits communicate with that end of the valve
which admits the steam into the cylinder. The cut-off is effected by.
shunting the spaces aforesaid on the aforesaid cylindrical valve over
these slits, thereby stopping any further supply of steam to the cylinder.
For this purpose we use a spindle adjusted to the axis of the cylinder,
of which the valve face is a portion, which spindle passes through a
stuffing box, and has a lever keyed upon it, which is connected by a

page_text: link to the lever described in the first part of our Invention, as being
actuated in one direction by the spiral cam, and in the other direction
by the spring or piston. This superimposed valve may be confined so as
not to move endwise, or it may partake of the endwise motion of the
valve upon which it rests.
Other improvements under this head consist also of a slide valve
having a superimposed valve upon it, somewhat similar to that above
described by preference, though a flat valve may be employed, except
that the slits for the steam are not parallel to the axis for giving motion
to the superimposed valve, but in a diagonal or screw direction in
respect to such axis, the direction of the slit for one end of the cylinder
being reversed to that for the other end, and the superimposed valve
"cuts off" the steam by a sliding movement in the direction of its axis,
the time of the cut-off being varied by oscillating or moving to and fro
the superimposed valve on or by the said axis (one way to cut-off sooner,
the other way to cut-off later) through mechanism which may be similar
to that above described, which receives movement by being combined
with the hydraulic apparatus hercin-before described under the second
head of our Invention, or with any well-known arrangements for
regulating cut-off apparatus.
The primary slide valve in the last-described arrangement is actuated
by an eccentric in the usual manner, and the superimposed slide may
be actuated by an eccentric; but we prefer (and this forms one feature
of our Invention) to work the last-named valve by a lever or levers, in
connection with the beam of beam engines, or some part having recip-
rocating motion from the piston of the engine, the movement of the.
said valve being given at the same time, but in the opposite direction
to that of the piston. When the pressure is great and the stroke is short
as in locomotive and agricultural engines, we make the said primary
valve nearly the length of the cylinder, which diminishes waste steam
in the ports. We arrange the exhaust port so as to run lengthway
of the cylinder instead of crosswise, by which means we obtain greater
wearing surface both on the valve and the facings upon which they
slide.

page_text: and steadied by the sides of the smoke box, in the inside of which,
attached to this bar, are 2, 3, or more taper nozzles of various
diameters at the small end, the larger end being the diameter of the
blast pipe at the under side of the bar. By sliding the bar any of
the nozzles may be brought over and into contact with the end of the
blast pipe. One end of the bar which protrudes through the sides of
the smoke box has rack teeth into which a pinion is geared, the shaft
from which goes to the fire-box end, or any convenient place, and has a
handle held by a notch; when the handle is in this notch one or other
of the nozzles is on the blast pipe, and the diameter of the pinion is so
proportioned to the distance between the nozzles that one revolution
thereof (by preference) shifts the bar the proper distance, so that any
one of the nozzles may be brought over the blast pipe, thereby varying
the draught through the furnace, as may be required.
The fifth part of our Invention relates to piston valves described
in the Specification of Letters Patent, dated March Seventh, One
thousand eight hundred and fifty, and Number 12,988, granted
to William McNaught, senior, and in the Specification of Letters
Patent dated December Twenty-seventh One thousand eight hundred
and fifty-six, and Numbered 3079, granted to the said William
McNaught and another, the said piston valve having four or more
projections on the steam side which would cover or uncover a like
number of slits through the sides of the cylindrical shell in which it
worked by turning the said piston valve round its axis, the steam being
admitted to and exhausted from the main cylinder by the usual recip-
rocating motion of the valve, as fully described in the Specifications of
the said Letters Patent.
Our present improvements consist in making the shell in which the
valve works in two separate pieces, one piece occupying the steam side
of the port, and the other the exhaust side, thus leaving the exhaust
side free from any obstruction. The piece on the steam side of the
port has the slits through which the steam passes in the thickness
of metal instead of opening into a chamber, as heretofore, thereby
diminishing waste space betwixt the valve and the cylinder.
Our improvements in the valve itself consists mainly in prolonging
the cylindrical part on the steam side, and adopting slits through it
corresponding with the slits in the shell instead of projections, as here-

page_text: tofore, and thereby obtaining a proportion of wearing surface better
adapted to high pressures than heretofore, not being liable to wear the
shell's taper. The steam slits are opened and closed by an intermittent
rotary motion in one direction; this is effected by connecting the levers
mentioned under the first head of our Invention to a lever and ratchet
.wheel mounted upon a hollow driving spindle which passes.through a
stuffing box on the valve chest in such a manner that when the last-
mentioned lever rises by the action of the cam it seizes hold of a fresh
tooth of the ratchet wheel, and when the drop occurs the piston valve
is thereby turned on its axis so as to cut off the steam by closing the slits,
or rotary motion is imparted by the well-known star wheel intermittent
motion. The reciprocating motion of the piston valve is communicated
by an eccentric in the usual manner; the rod from the piston valve is
attached to a swivel on the end of the valve spindle to admit of its being
turned round. This valve spindle passes through the hollow driving
spindle, and has 2, 4, or 6, or any number of projections which
take into a like number of grooves in the inside of the hollow spindle;
by this means the hollow spindle turns the valves round intermittently
without interfering with their reciprocating motion. The said hollow
driving spindle has a stuffing box at the outside cnd for the valve
spindle to pass through; or this stuffing box may be dispensed with
by arranging the hollow driving spindle so as to be entirely outside the
valve chest.
The first part of our Invention, together with other improvements, is
illustrated by those Figures of the accompanying Drawings herein-after
described (Sheet 1); Figure 1 is a plan sectional view; Figure 2 is a
section upon the line A, B, Figure 1; Figure 3 is an end sectional
elevation; and Figure 4 is a detached side view of the air cataract,
piston, and spring of one arrangement.
(Sheet 3), Fig. 5, is a plan view; Figure 6 is a side elevation; and
Figure 7 is an end elevation of another arrangement.
The same letters and figures of reference are used on the same and
corresponding parts of the Drawings.
a, the two spiral cams secured upon a shaft driven by being geared
with the crank shaft of the engine. These cams (a) act upon levers (a³)
which have their fulcrums upon arms a² keyed upon a rocking shaft a³.

page_text: In the arrangement shown by Figures 1, 3, and 4, the levers a¹ pass
through a slot (see Figure 4) in the piston rod (a) of the air cataract.
This rod at its lower end slides in a step guide (a), and at its upper end
it is secured by a nut, as shewn, to the valve lever (c), the rod (a¹) being
flattened at its upper end, so as to be sufficiently elastic to bend to the
curve of the arc in which the end of the lever c moves; but the piston
rod (at) may be connected with the valve lever (c) by a connecting rod
if desired; a is the piston; a' the spring which acts between the piston
and the end of the cataract cylinder a³, which is bolted to a part of the
frame or valve chest. The spiral cams (a) lift the piston rod a¹ and
open the valves in opposition to the force of the springs (a'), and when
the lever (a¹) comes to the drop upon the cam (a) the valve is suddenly
closed by the reaction of the spring (a'), the air in the cylinder (a³) below
the piston preventing concussion, as is well understood.
In the arrangement shown by Sheet 3, Figures 5, 6, and 7, where the
air cataract is dispensed with each lever a¹ is connected by a rod a with
a lever c* formed by two bars, one on one side, the other on the other
side of the ratchet wheel c', secured upon the hollow shaft m. This
double lever (c*) has two spring pawls attached to it, as shown, which
simultaneously act upon the teeth on opposite sides of the ratchet (c¹)
when the lever (c*) is oscillated by the action of the cam a and the flat
spring a, which is connected with the lever c* by a rod a", this spring
giving the sudden movement to the lever and ratchet and connected
valve when the end of the levers a¹ arrive at the drops on the cams,
concussion being prevented by the said spring a, bending over the
convex or round surface underneath. By using two cams and two
ratchets the cut-off may be adjusted for cach end of the cylinder; and
for quick speed two cams are to be preferred, though one cam and
ratchet may be sufficient.
We prefer to gear the shaft b with the crank shaft of the engine by
eliptical toothed wheels, the side view or profile of which is shown sur-
rounding Figures 12, 13, and 14, Sheet 2, by which means the angular
velocity of the cams a is made slow when the drop comes nearly opposite
the end of the lever a¹.
The rocking shaft a³, Sheets 1 and 3, receives movement to advance the
ends of the levers a¹ towards or withdraw them from the cams (a) by
connection with a governor through the arm a¹ on the rocking shaft a³

page_text: and rod a¹ or other rods and levers, and as the eliptical wheels cause
the cams to linger in their rotation in the vicinity of the drop a greater
range of cut-off can be obtained than when a simple uniform rotary
motion is imparted to the cam.
The second part of our Invention is illustrated by Figure 8 (Sheet 2),
a, the arms for the balls a² of the isochronous governor, which arms are
connected with shaft b, that rotates them in the ordinary manner. The
arms are double or forked, and have each a bowl a², upon which horns or
arms c¹ from a cross bar rest, which cross bar is attached to a weight c
that slides up and down upon the vertical shaft (6) of the governor,
this counterpoise weight being connected in the usual manner by a rod d
to the valve or other apparatus to be acted upon or governed. As the
balls (a) recede from or approach towards the vertical shaft (b) of the
governor their horizontal force, compounded of the centrifugal force and
the gravity of the balls, increases or diminishes, and the curve surface
of each arm (c¹) resting upon the bowls (a²) is such that its steepness
increases or decreases in the same ratio. The method of obtaining the
required curve of the arms or horns c¹ so that the counterpoise weight c
will act in the manner proposed is well known, and is described in works
on mechanics.
Other improvements under the second head of our Invention are
illustrated upon Sheet 1 by Figure 9, an enlarged longitudinal section of
the hydraulic apparatus detached; Figure 10, a side elevation, as com-
bined with the governor and valve of the engine to be regulated; and
Figure 11, a front elevation of the same. The varying of the cut-off is
usually performed by a well known arrangement known as the water wheel
governor, which is also commonly used in steam engines; this governor
is formed by two bevil wheels loose upon the spindle of the governor,
which gear with a third intermediate bevil wheel and turn it one way
or the other when the speed is greater or less than the speed fixed upon;
but when the speed is as required neither of the two bevils are rotated.
The wheels are turned with the spindle by a cottar, which is slided up
and down by the action of the governor; this cottar coming in contact
with projections from the boss of the bevil wheels upon the governor
spindle. The intermediate bevil wheel is commonly connected to the
valve gear by a train of wheels, and either a screw or a worm and worm
whcel segment.

page_text: Instead of the three bevil wheels friction pulleys arranged similarly
to the bevil wheels have been used. By our present arrangement
these bevil wheels or pulleys are dispensed with, though we use the
ordinary governor, as above described, for actuating our improved cut-
off valve mechanism when desired. d is a cylinder fixed upon a stand
or secured to a wall, as convenient; d¹ is the piston; and d², the piston
rod, which passes through an ordinary packing gland (see Figure 9), and
has a toothed rack d³ attached to it, which gears with a pinion d', tho
boss of which is tapped at one end with a right, at the other end with a
left handed screw thread. The boss of the pinion is long enough to slide
freely endways in bearings (as shown) to the required extent. One end
of a rod c connected with the governor is screwed to fit one end of the
boss of the pinion, and the end of another rod e¹ is screwed to fit the
other end of the said boss, and this rod is jointed with an arm e² on a
shaft e³, which has an arm e' that is connected by a rod e³ with the
arm (c) which actuates the valve spindle c², which arm (c³) corres-
ponds with the arm c³, Figure 12, Sheet 2. The rod e from the governor
is connected by means of a bell-crank lever with the cylindrical valve
rod d of the cylinder, as shown, fluid at a pressure, as herein-before
explained, being brought to the apparatus by means of the pipe d'.
The fluid exhausted from the cylinder passes through the tap d³, by
means of which the speed of action of the apparatus may be regulated
as desired. If the tap is wide open the piston d' (according to the
pressure of the fluid and the resistance to be overcome) will move
quickly, and if nearly closed the resistance to the escape of the exhaust
fluid will be increased, and the piston (¹) will move much more
slowly.
The action of the apparatus is as follows:-When the governor balls
rise or fall above or below their position when the speed is correct the
valve rod (d) of the hydraulic apparatus will be moved accordingly,
and will, as the case may be, admit fluid to one end of the cylinder, and
allow it to escape from the other end; consequently the piston (¹) of
the hydraulic apparatus will move one way or the other, according to
the action of the governor, and the toothed rack (d³) will rotate the
pinion (d), and this will shorten or lengthen the connections between
the governor and the cut-off valve to make it cut off earlier for the
increase of speed, and later for a decrease of speed. As the apparatus is
arranged the governor also acts through the pinion (d'), and its right
and left handed screwed boss directly, upon the cut-off valve..

page_text: Instead of applying the hydraulic apparatus as a lengthening and
shortening motion, as above described, it is obvious that the piston
rod (d) of the hydraulic apparatus may be connected directly with the
mechanism that gives the cut-off movement to the valve, but in this
case it would be requisite to have a throttle valve also in connection
with the governor, as the "hydraulic apparatus must necessarily be slow
in its motion, and sufficient traverse would have to be allowed to the
valve of the hydraulic apparatus, or in the connections between it and the
governor, to prevent it from restraining the free action of the governor
upon the throttle valve.
1
This hydraulic apparatus, applied either directly or as a lengthening
and [shortening motion, may be employed to regulate "cut-off" in
connection with the advancing and retarding levers above described, or
to helical or flat shaped superimposed sliders, hercin-after described, or
to any of the "differential movements or " rifled sleeves "now in uso 1
for varying the period of "cut-off."
I
"
The third part of our Invention is illustrated by Figures 1, 2, and 3
(Sheet 1). is the cylinder secured to a frame or bed; f¹ is the piston;
and f the piston rod; is the valve chest; are the primary slides,
and the spindle by which such slides are actuated by the ordinary 2
eccentric; c¹ are the superimposed slides upon the back of the primary
slide valves h, having slots in them, which are covered and uncovered by
the slits in the superimposed valves when it is oscillated. The super-
imposed valve c' and its facing or seating are made to form the segment
of a cylinder, as shown, and the valve spindles c², which actuate the 2
superimposed valves, are arranged and pass through stuffing boxes, as
shown; these spindles give oscillatory movement to the said valves.
Each spindle has a flat part upon it, which will fit a slot in the valve (as
shown) so as to oscillate the valve, but leave it free to be pressed by the
steam close against the facing upon the primary valve (h). The valve 3
spindles are actuated through the arms c by the mechanism herein-
before described in explaining the first part of our Invention. When
the cams (a) left the levers (a¹) the valves c¹ are brought so that their
slits are opposite the openings on the back of the primary valves (h), as
shown in Figure 2, and when the lever a¹ drops, the solid parts in the 3
superimposed valves cover the slits in the primary valve, and thus the
steam is cut off, the cut-off being made sooner or later by reason of the
governor acting upon the levers (a¹) as before explained.

page_text: Other improvements under the third head of our Invention are illus-
trated on Sheet 2 by Figure 12, a longitudinal section; Figure 13, a cross
section; and Figure 14, a plan. f represents the cylinder; is the primary
slide valve actuated by an eccentric in the ordinary manners; o¹ is a
superimposed slide having diagonal slots, as shown, those for one end
being reversed to those for the other end, and these slots correspond to
slots or ports formed in the back of the primary slide valve h. The
superimposed slide c¹ is secured upon a spindle c², which passes through
a stuffing box, as shown, and is connected to the working beam of a
beam engine, or with an eccentric or crank, the motion imparted by
the beam or eccentric being so arranged that the superimposed valve
will always travel in the opposite direction to the motion of the steam

page_text: Separate superimposed valves are mounted upon the primary valves
shown in Figure 16, that is, the valve shown in Figure 12 is in this case
divided into two halves, one half on the primary valve at one end, the
other half on the primary valve at the other end, both halves being
secured upon the same spindle which passes from end to end and passes
through a stuffing box, and is actuated, as described, in reference to
Figures 12 and 13.
.
Instead of the superimposed valve being a portion of a cylinder it may
be flat and arranged to fit the flat top of a primary valve, and may have
end and lateral motion given to it by arrangements similar to those
described in the Specification of a Patent, No. 2123, A.D. 1854, to William
McNaught, Sen'., (one of the present Patentees). This modification is
illustrated by Figure 17, a side elevation; Fig. 18, an end elevation; and
Fig. 19, a plan. The superimposed valve c' has end and lateral move-
ment imparted to it by a spindle c², as described in reference to Figures
12, 13, and 14, the valve being attached to the spindle by two arms c*
connected by a pin c³, upon which there is a bush or flat block that
slides up and down between projections or lugs upon the valve, as shown
in either case, whether circular or flat; the said superimposed valve has
a portion at the ends connected to the main portion of the same by stiff
ribs, as shewn, to support the same when passing the ports of the
primary value and thereby ensure even wearing of the same.
The fourth part of our Invention is illustrated by Figure 20, a plan
showing outline of part of a locomotive boiler in dotted line, and Figure 21,
an end elevation of part of the smoke box and blast pipe. a, blast pipe;
b, a bar sliding in bearings in the sides of the smoke box c, in which bar
are 2, 3, or more holes or nozzles 61, 6%, and 6³ to act as the blast pipe
orifice, which nozzles are all of the same size at the lower side of the a
bar, but vary in size at the outlet, and thus change the force of the blast
as required. There is a toothed rack formed upon one end of the b
in which a pinion d gears upon the end of a shaft e having suitable
bearings, this shaft extending to the fire-box end of the boiler where
there is a handlef by which it can be rotated, being arranged so that one
revolution of the handle (f) will slide the bar so as to bring the next

page_text: nozzle to that in the central position one way or the other exactly over
the blast pipe. The handle is held after each movement by a notch in a
quadrant and spring catch, as shewn, the catch being withdrawn when
the handle is to be turned.
The fifth part of the Invention is illustrated by Figures 5, 6, and 7,
hercin-before described, and by Figure 22, à longitudinal section, and
Figure 23, an end view of the cylindrical piston detached. frepresents
the cylinder of the engine; %, the cylindrical shell, shewn in section, for the
piston valve ; k¹, slots in the shell on the steam side. An outside view
of the piston valve for one end of the cylinder is shewn in Figure 5, and
a longitudinal section by Figure 22 and end view by Figure 23. The
valve consists of a principal boss and lid 1, which is held firmly against
the boss by the hoop and cottar 3. The part which constitutes the
piston has a boss in the centre, which is fitted upon the principal boss 7,
and is connected by one arm 1* with the periphery. This periphery is
expanded when required by a V wedge 1, as shown in Figures 22 and 23,
which is forced outwards by a bent spring 16, as shewn, which may if
desired be acted upon by a wedge or incline 1, which can be adjusted by
a screw nut from the end of the incline or wedge bolt, which comes to the
outside disc plate of the piston, or which, if preferred, packings may be
introduced from time to time in place of the wedge bolt. That portion
of the periphery which projects beyond the cover (") is perforated
with eight slits, corresponding with the slits in the before-mentioned
lining or casing. The spindle c² which works the valve passes through
the hollow spindle m, and has a swivel c' at the end, which is connected
to the eccentric rod c³, and this allows of rotary motion in the spindle c³,
while the reciprocating motion is imparted to it by the eccentric for
working the valve. The end of the hollow spindle m which is inside the
valve box has grooves in the inside (six are used, as shewn in Figure 5),
and the spindle has a like number of star-like projections, shewn by the
cross section, Figure 5ª, which take into and slide in the grooves in the
hollow spindle m.
Instead of the hollow spindle m entering the valve chest it may be
arranged to give rotary movement to the spindle c³ outside the valve
chest, and thus dispense with the stuffing box at the end of the hollow
spindle m. The cut-off is produced by the intermittent rotary motion
which is communicated to the hollow spindle by means of the cam (a)

page_text: and ratchet (c'), as herein-before described in reference to the first part
of our Invention. When the speed of the engine is below 40 revolutions
per minute we prefer to employ one cam (a) with two lifts, the cam
shaft (6) being driven by oval wheels, as herein-before described under
the first head of our Invention. When there is only one ratchet it
requires to have sixteen teeth; but when there are two ratchets and two
cams (a) each ratchet has eight teeth, as shown, the teeth of one ratchet
being set upon the shaft in respect to those of the other ratchet so as
to divide the revolutions of the hollow spindle m into sixteen parts or
movements, the slits and spaces being arranged that the same drop or
sudden movement of the ratchets closes the slits in one valve, and
thus effects the cut-off and at the same time puts the other valve into such
a position as to be open at the proper time.
In place of rotating the valve by cams and ratchets, we also employ
the well-known star wheel intermittent motion, the pin wheel of which
receives motion through a "differential movement" or "rifled sleeve."
We have now particularly described the nature of our said Invention,
and the mode of carrying the same into effect, and claim as our
Invention,―
Firstly. The combination and arrangement of mechanism for actuating i
valves to effect the sudden cut-off of steam to an engine, substantially
as herein-before described and illustrated by the accompanying Drawings,
when applied to valves, like the Corliss valve, modified on the gridiron
principle, rotating, piston, or disc valve, or a superimposed slide or other
valve upon another primary valve.
Secondly. The combination of cliptical, oval, or eccentric wheels with
cut-off mechanism, substantially as herein-before described under the
first head of our Invention.
Thirdly. The combination and arrangement of mechanism to form an
isochronous governor, in which a weight will act through or by means of
curved surfaces so as to resist the outward movement of the balls in
proportion to the increase of their horizontal force, substantially as
herein-before described and illustrated by the Drawings.
Fourthly. The combination of hydraulic apparatus with a governor,
either as a lengthening and shortening motion, or for actuating cut-off a
valves or throttle valves directly, substantially as herein-before described
and illustrated by the Drawings.

page_text: )
Fifthly. The combination of a superimposed valve having a curved
surface and gridiron slits with a primary slide valve, arranged and
actuated substantially as herein-before described and illustrated by
Figures 1, 2, 3, and 4 of the accompanying Drawings.
Sixthly. The combination of a superimposed valve, either the segment
of a cylinder or flat valve, having reversed, diagonal, or screw shaped
ports, with a primary slide valve, arranged and actuated as herein-before
described and illustrated by Figures 12, 13, 14, 15, 16, 17, 18, and 19 of
the accompanying Drawings, also giving reciprocating end motion to the
superimposed valve from the beam or piston of engines, substantially as
herein-before described.
Seventhly. The forming of the primary slide valve near the length of
the cylinder, making the exhaust port in the direction of the lengthway
of the cylinder, in the combination herein-before described and illus-
trated by Figures 12, 13, and 16 of the accompanying Drawings.
Eighthly. The adoption of such exhaust port or ports to the side of
the valve box, as described and illustrated by Figures 12, 13, and 16 of
the accompanying Drawings.
Ninthly. The mode of regulating the blast, as herein-before described
and illustrated by Figures 20 and 21 of the accompanying Drawings.
Tenthly. The improved arrangement, construction, and mode of
actuating the piston valves, herein-before described and illustrated by
Figures 5, 6, 7, 22, and 23 of the accompanying Drawings.
In witness whereof, we, the said William M'Naught, the elder,
John M'Naught, and William M'Naught, the younger, have
hereunto set our hands and seals, this Twentieth day of March,
One thousand eight hundred and seventy-five.
TIZM
CATATOTT