IMPROVEMENTS IN STEAM ENGINES
Year: 1878

page_text: LETTERS PATENT to Daniel Longworth, of Birmingham, in the County of
Warwick, Mechanical Engineer, for the Invention of "IMPROVEMENTS IN
STEAM ENGINES"
aled the 24th April 1878, and dated the 10th January 1878.
PROVISIONAL SPECIFICATION left by the said Daniel Longworth at the
Office of the Commissioners of Patents on the 10th January 1878.
DANIEL LONGWORTH, of Birmingham, in the County of Warwick, Mechanical
Engineer. "IMPROVEMENTS IN STEAM ENGINES."
My Invention has reference to the parts of steam engines which have for their
object the regulation of the speed of the engine, and the working of the engine
expansively; and my said Invention consists of the arrangements or combinations
of parts herein-after described, whereby the regulation of the speed and the working
of the engine expansively are effected in a simple and efficient manner.
When a "high-speed governor is employed to control the speed of the engine, I
mount the governor balls on pins, so that they may act as rollers against the interior
or under side of the counterpoise or slide, which, when the governor is vertical, is
placed above the said balls or rollers. The said counterpoise revolves with the
governor spindle, and is also capable of moving up and down upon it as the speed
of the engine varies.
The part of the counterpoise on which the said balls or rollers act may be varied
in form to suit the requirements of the expansion or throttle valve gear to which
the governor is connected. The governor may also be worked in a horizontal
position, and connected to the throttle valve direct or by means of levers in the
usual manner.
In engines furnished with automatic expansion gear controlled by the governor, I
employ the following arrangement. I will describe this part of my Invention as
applied to a horizontal steam engine, but it may be applied to vertical and other
steam engines. The main slide valve is constructed and worked in the usual
manner.

page_text: In some cases the main slide may be balanced, and it may be used as as steam
admission valve only, a separate valve and ports being provided for the exhaust
steam.
The expansion or cut-off valve may be either of the piston or plate kind, but I
prefer the latter. The steam admission ports in the main slide and expansion
valves are made, when required, of the gridiron type (that is, with one or more
ports in the expansion valve, corresponding with two or more ports in the main
slide valve), so as to diminish the motion of the expansion valve.
The ports in the expansion valve are so arranged that when the admission ports
at one end of the main slide valve are covered or shut by the expansion valve the
admission ports at the other end are left open.
When the expansion valve is at half stroke the admission ports at each end of
the main slide valve are half open. A vertical shaft carried in bearings in the
framing of the engine is caused to revolve at the same speed as the crank shaft of
the engine. On the said vertical shaft I mount a boss, around a portion of whose
circumference a helical cam is formed; a cotter passing through the boss and
through a longitudinal slot in the shaft causes the boss and cam to revolve with the
shaft, while the slot allows the boss and cam to be moved down and up by the
governor as the speed of the. engine varies. The boss and cam are connected by
means of a lever to the counterpoise or slide of the governor.
Instead of using a cotter and slot the vertical shaft may be made of a rectangular
or oval section, and the hole in the said boss and cam have a corresponding figure.
The said cam in revolving acts alternately on two rollers placed on opposite sides of
the said shaft. The said rollers are mounted on studs attached to a slide, which I
will call the roller slide, moving in guides in the framework of the engine. The
centres of the said rollers are not on the centre line of the slide and shaft, but are
placed on one side of that line, so that the steam may be distributed equally to
each stroke of the steam piston. The excentricity or throw of the said cam is such
that the greatest angle which its surface, acting on the rollers, makes with the
vertical shaft is the angle of repose of the acting surfaces, so that when the cam
acts on the rollers there is no tendency to force the cam and governor slide out of
the horizontal position.
The before-mentioned rollers and roller slide actuate the expansion valve by
mechanism constructed as follows:-This mechanism is of two kinds; one kind to
be used when the expansion valve is moved in the direction of the length of the
main slide valve rod, and the other kind to be used when the motion is at right
angles to the length of the main slide rod. This mechanism allows the expansion
valve to travel with the main slide valve, and at the same time allows of the
movement of the roller slide being communicated by the said mechanism to the
expansion valve at any position in the stroke of the steam piston. The expansion
valve remains in the position into which it is moved relative to the main slide
valve, and has no tendency to move therefrom.
In the arrangement in which the expansion valve is to be moved in the direction
of the length of the main slide valve rod, I make the expansion rod pass through
the interior of two tubular rods. The front tubular rod forms the main valve rod,
and is connected to the main valve rod slide, the latter being reciprocated by an
excentric in the usual manner. Both tubular rods pass through stuffing boxes, one
at the front and the other at the back of the valve chest, the said tubular rods
being connected together inside the steam chest by a rectangular frame and
screwed nuts.
There are two snugs, one at each end of the main slide valve, and the said frame
embraces these snugs, so that the main slide valve is actuated by the valve rods at
its extreme ends only. At the exterior ends of the said tubular rods stuffing boxes
are provided for the expansion valve rod. This valve rod is connected to the short
arm of a bell-crank lever, which rocks on a pin on the main valve rod slide, tho
other or long arm of the bell-crank lever is connected to a lever attached to a
rocking shaft carried in the framework of the engine, and in proximity to the roller

page_text: slide. Another lever attached to the rocking shaft is connected to the roller slide,
and the motion of the roller slide is thus communicated to the expansion valve.
In the arrangement in which the expansion valve is moved at right angles to the
direction of the length of the main slide valve rod, the main valve rod is of the
usual kind, and the expansion valve is provided with two snugs placed parallel with
the direction of the motion of the main slide valve rod. Between these snugs a
finger or single-toothed lever is placed which is attached to a rocking shaft which
passes through stuffing boxes at each end of the valve chest. The said rocking
shaft is also placed parallel with the direction of the motion of the main slide
valve rod.
Instead of tho said toothed lever a lever carrying a pin and block or roller may
be used. A lever is attached to the outer end of the said rocking shaft, and is
connected with the roller slide; the motion of the roller slide is thus communicated
to the expansion valve.
When it is required to start or reverse the engine by the hand gear attached to
the main slide valve, as in rolling mill engines, I make a portion of the lower part
of the helical cam of only one-half the excentricity or throw of the remaining
portion, so that when the governor slide falls to its lowest position, and the cam to
its highest position, as on the stopping of the engine, the aforesaid portion of the
cam rises into the same plain as the rollers on the roller slide, and the said portion
of the cam acting on either of the rollers moves the expansion valve into mid-
position, only leaving the steam admission ports at one end of the main slide valve
half open, and at the other end half closed, so that the steam can be admitted at
either end of the steam cylinder to move the engine either way by the attendant
moving the hand gear in the usual manner.
When the new automatic expansion gear described is applied to a pumping
engine for an accumulator, the rod from the accumulator may act on the governor
or cam lever, so that when the accumulator rises to the top of its lift the steam
may be cut off and the pumping engine stopped by the expansion valve instead of
by the usual throttle valve, which may be dispensed with.
In small pumping engines, and where it is not desirable to use a governor, the
helical cam may be moved up and down by a lever or screw, and fixed in different
positions to suit the speed of the engine, instead of throttling the steam by the
stop valve, as is usually done.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Daniel Longworth in the Great Seal Patent Office on the 27th
June 1878.
DANIEL LONGWORTH, of Birmingham, in the County of Warwick, Mechanical
Engineer. IMPROVEMENTS IN STEAM ENGINES."
"
My Invention has reference to the parts of steam engines which have for their
object the regulation of the speed of the engine and the working of the engine
expansively, and my said Invention consists of the arrangements or combinations of
parts herein-after described, whereby the regulation of the speed and the working
of the engine expansively are effected in a simple and efficient manner.
When a "high speed" governor is employed to control the speed of the engine I
mount the governor balls on pins, so that they may act as rollers against the
interior or under side of the counterpoise or slide, which, when the governor is
vertical, is placed above the said balls or rollers. The said counterpoise revolves
with the governor spindle, and is also capable of moving up and down upon it as
the speed of the engine varies.
The part of the counterpoise on which the said balls or rollers act may be varied
in form to suit the requirements of the expansion or throttle valve gear to which
the governor is connected. The governor may also be worked in a horizontal
position, and connected to the throttle valve direct, or by means of levers in the
usual manner.
In engines furnished with automatic expansion gear, controlled by the governor,
I employ the following arrangement I will describe this part of my Invention as
applied to a horizontal steam engine, but it may be applied to vertical and other
steam engines. The main slide valve is constructed and worked in the usual
manner.
In some cases the main slide valve may be balanced, and it may be used as a
steam admission valve only, a separate valve and ports being provided for the
exhaust steam.
The expansion or cut-off valve may be either of the piston or plate kind, but I
prefer the latter. The steam admission ports in the main slide and expansion valves
are made when required of the grid-iron type (that is, with one or more ports in
the expansion valve, corresponding with two or more ports in the main slide valve)
so as to diminish the motion of the expansion valve.
The ports in the expansion valve are so arranged that when the admission ports
at one end of the main slide valve are covered or shut by the expansion valve the
admission ports at the other end are left open.
When the expansion valve is at half stroke the admission ports at each end of
the main slide valve are half open. A vertical shaft carried in bearings in the
framing of the engine is caused to revolve at the same speed as the crank shaft of
the engine. On the said vertical shaft I mount a boss, around a portion of whose
circumference a helical cam is formed. A cotter passing through the boss and
through a longitudinal slot in the shaft causes the boss and cam to revolve with the
shaft, while the slot allows the boss and cam to be moved down and up by the
governor as the speed of the engine varies. The boss and cam are connected by
means of a lever to the counterpoise or slide of the governor.
Instead of using a cotter and slot the vertical shaft may be made of a rectangular
or oval section, and the hole in the said boss and cam have a corresponding figure.
The said cam in revolving acts alternately on two rollers placed on opposite sides of
the said shaft. The said rollers are mounted on studs attached to a slide, which 1
will call the roller slide, moving in guides in the framework of the engine. The
centres of the said rollers are not on the centre line of the slide and shaft, but are

page_text: placed on one side of that line, so that the steam may be distributed equally to
each stroke of the steam piston. The eccentricity or throw of the said cam is such
that the greatest angle which its surface acting on the rollers makes with the
vertical shaft is the angle of repose of the acting surfaces, so that when the cam acts
on the rollers there is no tendency to force the cam and governor slide out of the
horizontal position.
The before-mentioned rollers and roller slide actuato the expansion valve by
mechanism constructed as follows:-This mechanism is of two kinds, one kind to
be used when the expansion valve is moved in the direction of the length of the
main slide valve rod, and the other kind to be used when the motion is at right
angles to the length of the main slide rod. This mechamism allows the expansion
valve to travel with the main slide valve, and at the same time allows of the move-
ment of the roller slide being communicated by the said mechanism to the expansion
valve at any position in stroke of the steam piston. The expansion valve remains
in the position into which it is moved relative to the main slide valve, and has no
tendency to move therefrom.
In the arrangement, in which the expansion valve is to be moved in the direction
of the length of the main slide valve rod, I make the expansion rod pass through
the interior of two tubular rods. The front tubular, rod forms the main valve rod,
and is connected to the main valve rod slide, the latter being reciprocated by an
eccentric in the usual manner. Both tubular rods pass through stuffing boxes, one
at the front and the other at the back of the valve chest, the said tubular rods
being connected together inside the steam chest by a rectangular frame and screwed
nuts.
The
There are two snugs, one at each end of the main slide valve, and the said frame
embraces these snugs, so that the main slide valve is actuated by the valve rods at
its extreme ends only. At the exterior ends of the said tubular rods stuffing boxes
are provided for the expansion valve rod. This valve rod is connected to the short
arm of a bell-crank lever, which rocks on a pin on the main valve rod slide.
other or long arm of the bell-crank lever is connected to a lever attached to a rocking
shaft carried in the framework of the engine, and in proximity to the roller slide.
Another lever attached to the rocking shaft is connected to the roller slide, and the
motion of the roller slide is thus communicated to the expansion valve.
In the arrangement in which the expansion valve is moved at right angles to
the direction of the length of the main slide valve rod, the main valve rod
is of the usual kind, and the expansion valve is provided with two snugs placed
parallel with the direction of the motion of the main slide valve rod. Between
these snugs a finger or single tooothed lever is placed, which is attached to a rocking
shaft which passes through stuffing boxes at each end of the valve chest.
rocking shaft is also placed parallel with the direction of the motion of the main
slide valve rod.
The said
Instead of the said toothed lever a lever carrying a pin and block or roller may
be used. A lever is attached to the outer end of the said rocking shaft, and is
connected with the roller slide; the motion of the roller slide is thus communicated
to the expansion valve.
When it is required to start or reverse the engine by the hand gear attached to
the main slide valve, as in rolling mill engines, I make a portion of the lower part
of the helical cam of only one-half the eccentricity or throw of the remaining portion,
so that when the governor slide falls to its lowest position, and the cam to its highest
position, as on the stopping of the engine, the aforesaid portion of the cam rises into
the same plane as the rollers on the roller slide, and the said portion of the cam
acting on either of the rollers moves the expansion valve into mid-position only,
leaving the steam admission ports at one end of the main slide valve half open, and
at the other end half closed, so that the steam can be admitted at either end of the
steam cylinder to move the engine either way by the attendant moving the hand
gear in the usual manner.

page_text: When the automatic expansion gear described is applied to a pumping engine for
an accumulator, the rod from the accumulator may act on the governor or cam lever,
so that when the accumulator rises to the top of its lift, the steam may be cut off,
and the pumping engine stopped by the expansion valve instead of by the usual
throttle valve, which may be dispensed with.
In small pumping engines, and where it is not desirable to use a governor, the
helical cam may be moved up and down by a lever or screw, and fixed in different
positions to suit the speed of the engine, instead of throttling the steam by the stop
valve, as is usually done.
Having explained the nature of my Invention, I will proceed to describe with
reference to the accompanying Drawing, the manner in which the same is to be
performed.
Figures 1 and 4 are side elevations partly in section; Figures 2 and 5 are end
elevations partly in section; and Figures 3 and 6 are plans, partly in section, of
horizontal steam engines constructed with automatic expansion gear according to
my Invention.
The improved arrangement of high speed governor is shown in Figures 1 and 4;
a, a, are the governor balls or rollers mounted on pins or axes in the ball
arms a', a', the said ball arms being carried by the suspension pin or axis a² in
the governor spindle a³, which spindle is driven by bevel gearing from the crank
shaft b of the engine. The said rollers a, a, act on the interior or under side of the
counterpoise or slide c which is mounted on the governor spindle a³ above the
suspension pin a², and has the general figure of a hollow cone. By this arrange-
ment the bearing a in which the governor spindle a³ rotates can be brought much
nearer to the suspension pin a² of the ball arms a¹ than can be done when the
counterpoise or slide c is placed below the suspension pin a²; the spindle is thus
very effectually steadied, and the governor made more durable.
A pin or cotter passes through the slide c, and through a slot in the governor
spindle a³ as usually constructed to cause the slide c to revolve with the spindle a³,
whilst it is capable of moving up and down upon it, as the speed of the engine and
governor varies ;
d is the main slide valve of the engine which is reciprocated by
the eccentric b¹ on the crunk shaft b in the usual manner.
The steam admission ports in the main slide valve d, shewn in the Drawing, are
of the gridiron type, but other types of slide valves may be employed; e is the
expansion or cut-off valve, which may be in one piece, as shewn in Figures 1, 2,
and 3, or in two parts, as shewn in Figures 4, 5, and 6. The said expansion valve e
has ports in it corresponding to the steam admission ports in the main slide valve d;
fis a vertical shaft carried in suitable bearings in the bracket f' attached to the
framing of the engine. The said shaft f is caused to rotate so as to make the same
number of revolutions per minute at the crank shaft of the engine by means of
the bevel gearing and shaft at f³, as shewn; g is a boss or sleeve mounted on the
said shaft f
A cotter g' passed through the boss g and through a slot in the shaft f, causes the
boss g to revolve with the shaft, whilst it is capable of being moved up or down
upon it by means of the weighted lever y² connected to the counterpoise or slide c
of the governor.
Where required, a "slow speed" governor may be mounted on the vertical shaft f,
and be connected by levers to the said boss g in place of the high speed governor
and lever g; g³ is the spiral or helical cam attached to the boss g, and having the
form in cross section shewn in Figure 3.
When the engine is at its slowest speed, the said helical cam g³ actuating the
expansion valve e, through the rollers h, h, and the mechanisın herein-after described,
causes the said expansion valve to cut off the steam at the latest part of the stroke
of the steam piston.

page_text: As the speed of the engine and governor increases, the slide o of the governor
rises, and acting through the lever g³ causes the boss g and cam g³ to move down-
wards, the twist in the said cam being so arranged that as the cam moves downwards
a more advanced section of the spiral cam is brought into the same horizontal plane
as the rollers h, h, and thus acting sooner on the said rollers causes the expansion
valve e to cut off the steam earlier in the stroke of the steam piston. The steam
supply of each stroke is by this means placed under the control of the governor.
The rollers h, h, are placed on opposite sides of the shaft f, and are mounted on
studs in the slide h¹, the said slide moving in V guides in the bracket f¹. The
rollers h, h, are placed out of the centre line of the slide h' and shaft f, as shewn in
Figures 3 and 5; by this arrangement the angularity of the crank shaft connecting
rod b' is allowed for, and the steam distributed inore equally to each stroke of the
steam piston.
The eccentricity or throw of the cam g³ is of such dimensions that the greatest
angle which its surface, acting on the rollers h, h, makes with the axis of the shaft f
is the angle of repose of the acting surfaces, so that there is no tendency to force
the cam g³ and governor slide c out of the horizontal position, thus dispensing
with the use of cataracts or air cushions attached to the said cam.
As the cam g
does not act on either of the rollers, h during a large portion of its rotation, the
governor has time to assume any new position consequent on a change of speed.
The greatest sensitiveness of governing action is thus obtained; instead of the
rollers h, h, fixed tappets of suitable form may be attached to the roller slide h¹ for.
the cain g³ to act upon.
The rollers h, h, and roller slide h¹ actuate the expansion valve e through
mechanism which I will now describe. This mechanism is of two kinds, one kind
to be used when the expansion valve e is moved in the direction of the length of
the main slide valve rod d, as shewn in Figures 1, 2, and 3, and the other kiud to
be used when the expansion valve e is moved at right angles to the main slide
valve rod d¹, as shewn in Figures 4, 5, and 6.
In Figures 1, 2, and 3, the expansion valve rod e¹ passes through the interior of two
tubular rods d' and d. The front tubular rod d¹ forms the main valve rod, and is
connected to the main valve rod slide d by the plate and bolts, as shewn, or in any
other convenient way. The eccentric rod 63 is connected to the slide d³ by the
pin 63. The slide d³ and main slide valve d are thus reciprocated in the usual
manner. The tubular rods d¹ and d pass through stuffing boxes, one in the front
and one at the back of the steam chest, as shewn. The said tubular rods d¹ and
d² are connected together inside the steam chest by the rectangular frame d* and
screwed nuts, as shewn.
The main slide valve d has a snug at each end, which is embraced by the frame d*,
so that the main slide valve d is actuated at its extreme ends only. The expansion
valve rod e¹ has a stuffing box near one end in the slide d³, and a stuffing box dat
the other end attached to the tubular rod d². The expansion valve rod is thus
placed in equilibrium, and the steam pressure has no tendency to move it.
The expansion valve rod e¹ is attached at its front end to a cross head 62, and by
ineans of a link e³ is connected to the short arm of a bell-crank lever k, which is
mounted on and free to rock upon the pin 6%, carried in the main valve rod slide d³
and moving with it. The other or long arm of the bell-crank lever k is connected
by a link or other suitable connection to the lever, attached to the rocking
shaft, carried in bearings in the bracket f¹. Another lever, also attached to
the said rocking shaft, is, by means of the link k³, connected to the roller slide h',
which carries the rollers h, h, actuated by the can g³ on the vertical shaft f, as
already described. The cam g in rotation gives an intermittent reciprocating
motion to the expansion valve e, which covers or closes the steam admission ports
to one end of the main slide valve d, and opens the ports at the other end, tho
latter ports being closed in their turn to cut off the steam, and the former ports

page_text: opened to admit the steam. The point in the stroke at which the port is closed and
the steam cut off depends on the speed of the engine and horizontal position of the
spiral cam g³, as previously described.
In Figures 4, 5, and 6, the main valve rod d' is of the usual kind. The expan-
sion valves e, e, are shewn as constructed in two parts, each capable of moving in
guides on the main slide valve d, but at right angles to the motion of the latter.
The said expansion valves e, e, are each provided with two snugs or projections e*,
the position of which with respect to the main slide valve rod d¹ will be understood
by reference to Figure 5.
Between the said snugs e a finger or single toothed lever is placed. The
said toothed lever is attached to the rocking shaft l, which is placed parallel with
the main valve rod d¹, and is free to rock in bearings, which also form stuffing
boxes placed one at each end of the steam chest, as shewn. A lever 12 is also
attached to the said rocking shaft l, and is by means of the link 3 connected to
the roller slide h¹, actuated by the spiral cam g³ on the vertical spindle f, as before
described.
It will be seen that in both of the arrangements described, the expansion valve e
moves with the main slide valve d, except when it is operated upon by the cam g³,
and remains in any position on the valve d, into which it may have been brought
by the cam g³, and has no tendency to move therefrom. The expansion valve has
thus a minimum of motion, and is more durable, and requires less power to move it
than expansion valves of the usual construction.
In Figures 4, 5, and 6, the usual hand starting and reversing gear is shewn, con-
nected with the main slide valve d. To enable the said hand-starting gear to be
used when the engine is fitted with an expansion valve, I make the lower portion g'
(or in some cases it may be the upper portion) of the cam g³ of the section, shewn
in Figure 6, having only one half the throw or eccentricity of the remaining
portion, so that when the governor slide c falls to its lowest position, as on
the stopping of the engine, the aforesaid portion 9' of the cam g³ rises into the
same plane as the rollers h, h, on the roller slide h', and acting on one or other of
the said rollers moves the expansion valves e, e, into mid-position only, as shewn
in Figures 5 and 6, leaving the steam admission ports at one end of the main
slide valve d half open, and at the other end half closed, so that the steam can be
admitted at either end of the steam cylinder to move the engine either way by the
attendant moving the hand gear in the usual manner.
When the governor slide c rises above its lowest position as the speed of the
engine increases, the before-mentioned part g³ of the cam acts on the rollers, causing
the expansion valves e to cut the steam off alternately from each end of the cylinder
in the manner previously described.
Having now described the nature of my Invention, and the manner in which the
same is to be performed, I wish it to be understood that I do not limit myself to
the precise details herein described and illustrated, but I claim as my Invention of
improvements in steam engines,--
First. In a high speed governor, in which the balls or rollers act directly on the
counterpoise or slide, I claim the placing of the counterpoise or slide on the
governor spindle above the balls or rollers, for the purpose and substantially as
described, and illustrated in the accompanying Drawing.
Secondly. The combination of the spiral or helical cam, constructed as described,
and illustrated in the accompanying Drawing, with the rollers and roller slide or
their equivalents for actuating the expansion valves of steam engines in the manner
and substantially as described.
Thirdly. The combination of the two tubular rods d' and d with the expansion
valve rod e¹ and bell-crank lever k, for the purpose and substantially as described,
and illustrated in Figures 1, 2, and 3 of the accompanying Drawing.
Fourthly. The combination with the expansion valves of the single finger or toothed

page_text: lever and rocking shaft for the purpose and substantially as described, and illus-
trated in Figures 4, 5, and 6 of the accompanying Drawing.
In witness whereof, I, the said Daniel Longworth, have hereunto set my hand
and seal, this Twentieth day of June, in the year of our Lord One thousand
eight hundred and seventy-eight.
Witness,
JOSEPH HAMILTON,
2, Mayfair Villas,
Battersea,
London.
DANIEL LONGWORTH. (LS.)

page_text: LETTERS PATENT to Daniel Longworth, of Birmingham, in the County of
Warwick, Mechanical Engineer, for the Invention of "IMPROVEMENTS IN
STEAM ENGINES.”
Sealed the 24th April 1878, and dated the 10th January 1878.
PROVISIONAL SPECIFICATION left by the said Daniel Longworth at the
Office of the Commissioners of Patents on the 10th January 1878.
DANIEL LONGWORTH, of Birmingham, in the County of Warwick, Mechanical
Engineer. "IMPROVEMENTS IN STEAM ENGINES."
My Invention has reference to the parts of steam engines which have for their
object the regulation of the speed of the engine, and the working of the engine
expansively; and my said Invention consists of the arrangements or combinations
of parts herein-after described, whereby the regulation of the speed and the working
of the engine expansively are effected in a simple and efficient manner.
When a "high-speed" governor is employed to control the speed of the engine, I
mount the governor balls on pins, so that they may act as rollers against the interior
or under side of the counterpoise or slide, which, when the governor is vertical, is
placed above the said balls or rollers. The said counterpoise revolves with the
governor spindle, and is also capable of moving up and down upon it as the speed
of the engine varies.
The part of the counterpoise on which the said balls or rollers act may be varied
in form to suit the requirements of the expansion or throttle valve gear to which
the governor is connected. The governor may also be worked in a horizontal
position, and connected to the throttle valve direct or by means of levers in the
usual manner.
In engines furnished with automatic expansion gear controlled by the governor, I
employ the following arrangement. I will describe this part of my Invention as
applied to a horizontal steam engine, but it may be applied to vertical and other
steam engines. The main slide valve is constructed and worked in the usual
manner.

page_text: In some cases the main slide may be balanced, and it may be used as as steam
admission valve only, a separate valve and ports being provided for the exhaust
steam.
The expansion or cut-off valve may be either of the piston or plate kind, but I
prefer the latter. The steam admission ports in the main slide and expansion
valves are made, when required, of the gridiron type (that is, with one or more
ports in the expansion valve, corresponding with two or more ports in the main
slide valve), so as to diminish the motion of the expansion valve.
The ports in the expansion valve are so arranged that when the admission ports
at one end of the main slide valve are covered or shut by the expansion valve the
admission ports at the other end are left open.
When the expansion valve is at half stroke the admission ports at each end of
the main slide valve are half open. A vertical shaft carried in bearings in the
framing of the engine is caused to revolve at the same speed as the crank shaft of
the engine. On the said vertical shaft I mount a boss, around a portion of whose
circumference a helical cam is formed; a cotter passing through the boss and
through a longitudinal slot in the shaft causes the boss and cam to revolve with the
shaft, while the slot allows the boss and cam to be moved down and up by the
governor as the speed of the engine varies. The boss and cam are connected by
mcans of a lever to the counterpoise or slide of the governor.
Instead of using a cotter and slot the vertical shaft may be made of a rectangular
or oval section, and the hole in the said boss and cam have a corresponding figure.
The said cam in revolving acts alternately on two rollers placed on opposite sides of
the said shaft. The said rollers are mounted on studs attached to a slide, which I.
will call the roller slide, moving in guides in the framework of the engine. The
centres of the said rollers are not on the centre line of the slide and shaft, but are
placed on one side of that line, so that the steam may be distributed equally to
each stroke of the steam piston. The excentricity or throw of the said cam is such
that the greatest angle which its surface, acting on the rollers, makes with the
vertical shaft is the angle of repose of the acting surfaces, so that when the cam
acts on the rollers there is no tendency to force the cam and governor slide out of
the horizontal position.
The before-mentioned rollers and roller slide actuate the expansion valve by
mechanism constructed as follows:-This mechanism is of two kinds; one kind to
be used when the expansion valve is moved in the direction of the length of the
main slide valve rod, and the other kind to be used when the motion is at right
angles to the length of the main slide rod. This mechanism allows the expansion
valve to travel with the main slide valve, and at the same time allows of the
movement of the roller slide being communicated by the said mechanism to the
expansion valve at any position in the stroke of the steam piston. The expansion
valve remains in the position into which it is moved relative to the main slide
valve, and has no tendency to move therefrom.
In the arrangement in which the expansion valve is to be moved in the direction
of the length of the main slide valve rod, I make the expansion rod pass through
the interior of two tubular rods. The front tubular rod forms the main valve rod,
and is connected to the main valve rod slide, the latter being reciprocated by an
excentric in the usual manner. Both tubular rods pass through stuffing boxes, one
at the front and the other at the back of the valve chest, the said tubular rods
being connected together inside the steam chest by a rectangular frame and
screwed nuts.
There are two snugs, one at each end of the main slide valve, and the said frame
embraces these snugs, so that the main slide valve is actuated by the valve rods at
its extreme ends only. At the exterior ends of the said tubular rods stuffing boxes
are provided for the expansion valve rod. This valve rod is connected to the short
arm of a bell-crank lever, which rocks on a pin on the main valve rod slide, the
other or long arm of the bell-crank lever is connected to a lever attached to a
rocking shaft carried in the framework of the engine, and in proximity to the roller

page_text: slide. Another lever attached to the rocking shaft is connected to the roller slide,
and the motion of the roller slide is thus communicated to the expansion valve.
In the arrangement in which the expansion valve is moved at right angles to the
direction of the length of the main slide valve rod, the main valve rod is of the
usual kind, and the expansion valve is provided with two snugs placed parallel with
the direction of the motion of the main slide valve rod. Between these snugs a
finger or single-toothed lever is placed which is attached to a rocking shaft which
passes through stuffing boxes at each end of the valve chest. The said rocking
shaft is also placed parallel with the direction of the motion of the main slide
valve rod.
Instead of the said toothed lever a lever carrying a pin and block or roller may
be used. A lever is attached to the outer end of the said rocking shaft, and is
connected with the roller slide; the motion of the roller slide is thus communicated
to the expansion valve.
When it is required to start or reverse the engine by the hand gear attached to
the main slide valve, as in rolling mill engines, I make a portion of the lower part
of the helical cam of only one-half the excentricity or throw of the remaining
portion, so that when the governor slide falls to its lowest position, and the cam to
its highest position, as on the stopping of the engine, the aforesaid portion of the
cam rises into the same plain as the rollers on the roller slide, and the said portion
of the cam acting on either of the rollers moves the expansion valve into mid-
position, only leaving the steam adinission ports at one end of the main slide valve
half open, and at the other end half closed, so that the steam can be admitted at
either end of the steam cylinder to move the engine either way by the attendant
moving the hand gear in the usual manner.
When the new automatic expansion gear described is applied to a pumping
engine for an accumulator, the rod from the accumulator may act on the governor
or cam lever, so that when the accumulator rises to the top of its lift the steam
may be cut off and the pumping engine stopped by the expansion valve instead of
by the usual throttle valve, which may be dispensed with.
In small pumping engines, and where it is not desirable to use a governor, the
helical cam may be moved up and down by a lever or screw, and fixed in different
positions to suit the speed of the engine, instead of throttling the steam by the
stop valve, as is usually done.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Daniel Longworth in the Great Seal Patent Office on the 27th
June 1878.
DANIEL LONGWORTH, of Birmingham, in the County of Warwick, Mechanical
Engineer. "IMPROVEMENTS IN STEAM ENGINES."
My Invention has reference to the parts of steam engines which have for their
object the regulation of the speed of the engine and the working of the engine
expansively, and my said Invention consists of the arrangements or combinations of
parts herein-after described, whereby the regulation of the speed and the working
of the engine expansively are effected in a simple and efficient manner.
When a "high speed" governor is employed to control the speed of the engine I
mount the governor balls on pins, so that they may act as rollers against the
interior or under side of the counterpoise or slide, which, when the governor is
vertical, is placed above the said balls or rollers. The said counterpoise revolves
with the governor spindle, and is also capable of moving up and down upon it as
the speed of the engine varies.
The part of the counterpoise on which the said balls or rollers act may be varied
in form to suit the requirements of the expansion or throttle valve gear to which
the governor is connected. The governor may also be worked in a horizontal
position, and connected to the throttle valve direct, or by means of levers in the
usual manner.
In engines furnished with automatic_expansion gear, controlled by the governor,
I employ the following arrangement -I will describe this part of my Invention as
applied to a horizontal steam engine, but it may be applied to vertical and other
steam engines. The main slide valve is constructed and worked in the usual
manner.
In some cases the main slide valve may be balanced, and it may be used as a
steam admission valve only, a separate valve and ports being provided for the
exhaust steam.
The expansion or cut-off valve may be either of the piston or plate kind, but I
prefer the latter. The steam admission ports in the main slide and expansion valves
are made when required of the grid-iron type (that is, with one or more ports in
the expansion valve, corresponding with two or more ports in the main slide valve)
so as to diminish the motion of the expansion valve.
The ports in the expansion valve are so arranged that when the admission ports
at one end of the main slide valve are covered or shut by the expansion valve the
admission ports at the other end are left open.
When the expansion valve is at half stroke the admission ports at each end of
the main slide valve are half open. A vertical shaft carried in bearings in the
framing of the engine is caused to revolve at the same speed as the crank shaft of
the engine. On the said vertical shaft I mount a boss, around a portion of whose
circumference a helical cam is formed. A cotter passing through the boss and
through a longitudinal slot in the shaft causes the boss and cam to revolve with the
shaft, while the slot allows the boss and cam to be moved down and up by the
governor as the speed of the engine varies. The boss and cam are connected by
means of a lever to the counterpoise or slide of the governor.
Instead of using a cotter and slot the vertical shaft may be made of a rectangular
or oval section, and the hole in the said boss and cam have a corresponding figure.
The said cam in revolving acts alternately on two rollers placed on opposite sides of
the said shaft. The said rollers are mounted on studs attached to a slide, which 1
will call the roller slide, moving in guides in the framework of the engine. The
centres of the said rollers are not on the centre line of the slide and shaft, but are

page_text: placed on one side of that line, so that the steam may be distributed equally to
each stroke of the steam piston. The eccentricity or throw of the said cam is such
that the greatest angle which its surface acting on the rollers makes with the
vertical shaft is the angle of repose of the acting surfaces, so that when .the cam acts
on the rollers there is no tendency to force the cam and governor slide out of the
borizontal position.
The before-mentioned rollers and roller slide actuate the expansion valve by
mechanism constructed as follows:-This mechanisin is of two kinds, one kind to
be used when the expansion valve is moved in the direction of the length of the
main slide valve rod, and the other kind to be used when the motion is at right
angles to the length of the main slide rod. This mechamism allows the expansion
valve to travel with the main slide valve, and at the same time allows of the move-
ment of the roller slide being communicated by the said mechanism to the expansion
valve at any position in stroke of the steam piston. The expansion valve remains
in the position into which it is moved relative to the main slide valve, and has no
tendency to move therefrom.
In the arrangement, in which the expansion valve is to be moved in the direction
of the length of the main slide valve rod, I make the expansion rod pass through
the interior of two tubular rods. The front tubular rod forms the main valve rod,
and is connected to the main valve rod slide, the latter being reciprocated by an
eccentric in the usual manner. Both tubular rods pass through stuffing boxes, one
at the front and the other at the back of the valve chest, the said tubular rods
being connected together inside the steam chest by a rectangular frame and screwed
nuts.
The
There are two snugs, one at each end of the main slide valve, and the said frame
embraces these snugs, so that the main slide valve is actuated by the valve rods at
its extreme ends only. At the exterior ends of the said tubular rods stuffing boxes
are provided for the expansion valve rod. This valve rod is connected to the short
arm of a bell-crank lever, which rocks on a pin on the main valve rod slide.
other or long arm of the bell-crank lever is connected to a lever attached to a rocking
shaft carried in the framework of the engine, and in proximity to the roller slide.
Another lever attached to the rocking shaft is connected to the roller slide, and the
motion of the roller slide is thus communicated to the expansion valve.
In the arrangement in which the expansion valve is moved at right angles to
the direction of the length of the main slide valve rod, the main valve rod
is of the usual kind, and the expansion valve is provided with two snugs placed
parallel with the direction of the motion of the main slide valve rod. Between
these snugs a finger or single tooothed lever is placed, which is attached to a rocking
shaft which passes through stuffing boxes at each end of the valve chest. The said
rocking shaft is also placed parallel with the direction of the motion of the main
slide valve rod.
Instead of the said toothed lever a lever carrying a pin and block or roller may
be used. A lever is attached to the outer end of the said rocking shaft, and is
connected with the roller slide; the motion of the roller slide is thus communicated
to the expansion valve.
When it is required to start or reverse the engine by the hand gear attached to
the main slide valve, as in rolling mill engines, I make a portion of the lower part
of the helical cam of only one-half the eccentricity or throw of the remaining portion,
so that when the governor slide falls to its lowest position, and the cam to its highest
position, as on the stopping of the engine, the aforesaid portion of the cam rises into
the same plane as the rollers on the roller slide, and the said portion of the cam
acting on either of the rollers moves the expansion valve into mid-position only,
leaving the steam admission ports at one end of the main slide valve half open, and
at the other end half closed, so that the steam can be admitted at either end of the
steam cylinder to move the engine either way by the attendant moving the hand
gear in the usual manner.

page_text: When the automatic expansion gear described is applied to a pumping engine for
an accumulator, the rod from the accumulator may act on the governor or cam lever,
so that when the accumulator rises to the top of its lift, the steam may be cut off,
and the pumping engine stopped by the expansion valve instead of by the usual
throttle valve, which may be dispensed with.
In small pumping engines, and where it is not desirable to use a governor, the
helical cam may be moved up and down by a lever or screw, and fixed in different
positions to suit the speed of the engine, instead of throttling the steam by the stop
valve, as is usually done.
Having explained the nature of my Invention, I will proceed to describe with
reference to the accompanying Drawing, the manner in which the same is to be
performed.
Figures 1 and 4 are side elevations partly in section; Figures 2 and 5 are end
elevations partly in section; and Figures 3 and 6 are plans, partly in section, of
horizontal steam engines constructed with automatic expansion gear according to
my Invention.
The improved arrangement of high speed governor is shown in Figures 1 and 4;
a, a, are the governor balls or rollers mounted on pins or axes in the ball
arms a', a', the said ball arms being carried by the suspension pin or axis a² in
the governor spindle a³, which spindle is driven by bevel gearing from the crank
shaft b of the engine. The said rollers a, a, act on the interior or under side of the
counterpoise or slide c which is mounted on the governor spindle as above the
suspension pin a², and has the general figure of a hollow cone. By this arrange-
ment the bearing a in which the governor spindle a³ rotates can be brought much
nearer to the suspension pin a² of the ball arms a¹ than can be done when the
counterpoise or slide c is placed below the suspension pin a²; the spindle is thus
very effectually steadied, and the governor made more durable.
A pin or cotter passes through the slide c, and through a slot in the governor
spindle as as usually constructed to cause the slide c to revolve with the spindle a³,
whilst it is capable of moving up and down upon it, as the speed of the engine and
governor varies; d is the main slide valve of the engine which is reciprocated by
the eccentric b¹ on the crank shaft b in the usual manner.
The steam admission ports in the main slide valve d, shewn in the Drawing, are
of the gridiron type, but other types of slide valves may be employed; e is the
expansion or cut-off valve, which may be in one piece, as shewn in Figures 1, 2,
and 3, or in two parts, as shewn in Figures 4, 5, and 6. The said expansion valve e
has ports in it corresponding to the steain admission ports in the main slide valve d;
fis a vertical shaft carried in suitable bearings in the bracket f' attached to the
framing of the engine. The said shaft fis caused to rotate so as to make the same
number of revolutions per minute at the crank shaft of the engine by means of
the bevel gearing and shaft at fƒ³, as shewn ; is a boss or sleeve mounted on the
said shaft f.
A cotter g' passed through the boss g and through a slot in the shaft f, causes the
boss to revolve with the shaft, whilst it is capable of being moved up or down
upon it by means of the weighted lever g³ connected to the counterpoise or slide c
of the governor.
Where required, a "slow speed" governor may be mounted on the vertical shaft f
and be connected by levers to the said boss g in place of the high speed governor
and lever g; g is the spiral or helical cam attached to the boss g, and having the
form in cross section shewn in Figure 3.
When the engine is at its slowest speed, the said helical cam 93 actuating the
expansion valve e, through the rollers h, h, and the mechanisin herein-after described,
causes the said expansion valve to cut off the stern at the latest part of the stroke
of the steam piston,

page_text: As the speed of the engine and governor increases, the slide c of the governor
rises, and acting through the lever gª causes the boss g and cam g³ to move down-
wards, the twist in the said cam being so arranged that as the cam moves downwards
a more advanced section of the spiral cam is brought into the same horizontal plane
as the rollers h, h, and thus acting sooner on the said rollers causes the expansion
valve e to cut off the steam earlier in the stroke of the steam piston. The steam
supply of each stroke is by this means placed under the control of the governor.
The rollers h, h, are placed on opposite sides of the shaft f, and are mounted on
studs in the slide h¹, the said slide moving in V guides in the bracket f¹. The
rollers h, h, are placed out of the centre line of the slide h' and shaft f, as shewn in
Figures 3 and 5; by this arrangement the angularity of the crank shaft connecting
rod b is allowed for, and the steam distributed more equally to each stroke of the
steam piston.
The eccentricity or throw of the cam g³ is of such dimensions that the greatest
angle which its surface, acting on the rollers h, h, makes with the axis of the shaft f
is the angle of repose of the acting surfaces, so that there is no tendency to force
the cam g³ and governor slide c out of the horizontal position, thus dispensing
with the use of cataracts or air cushions attached to the said cam. As the cam g³
does not act on either of the rollers h during a large portion of its rotation, the
governor has time to assume any new position consequent on a change of speed.
The greatest sensitiveness of governing action is thus obtained; instead of the
rollers h, h, fixed tappets of suitable form may be attached to the roller slide h¹ for
the can g³ to act upon.
The rollers h, h, and roller slide h¹ actuate the expansion valve e through
mechanism which I will now describe. This mechanism is of two kinds, one kind
to be used when the expansion valve e is moved in the direction of the length of
the main slide valve rod d', as shewn in Figures 1, 2, and 3, and the other kind to
be used when the expansion valve e is moved at right angles to the main slide
valve rod d', as shewn in Figures 4, 5, and 6.
In Figures 1, 2, and 3, the expansion valve rod el passes through the interior of two
tubular rods d¹ and d. The front tubular rod d forms the main valve rod, and is
connected to the main valve rod slide d by the plate and bolts, as shewn, or in any
other convenient way. The eccentric rod 6 is connected to the slide d³ by the
pin 63. The slide d³ and main slide valve d are thus reciprocated in the usual
manner. The tubular rods d' and d³ pass through stuffing boxes, one in the front
and one at the back of the steam chest, as shown. The said tubular rods d¹ and
d2 are connected together inside the steam chest by the rectangular frame d' and
screwed nuts, as shown.
The main slide valve d has a snug at each end, which is embraced by the frame d*,
so that the main slide valve d is actuated at its extreme ends only. The expansion
valve rod e¹ has a stuffing box near one end in the slide d³, and a stuffing box d³ at
the other end attached to the tubular rod d. The expansion valve rod is thus
placed in equilibrium, and the steam pressure has no tendency to move it.
The expansion valve rod e¹ is attached at its front end to a cross head e³, and by
means of a link e³ is connected to the short arm of a bell-crank lever k, which is
mounted on and free to rock upon the pin 6s, carried in the main valve rod slide d³
and moving with it. The other or long arm of the bell-crank lever k is connected
by a link k or other suitable connection to the lever ², attached to the rocking
shaft, carried in bearings in the bracket f¹. Another lever, also attached to
the said rocking shaft, is, by means of the link k³, connected to the roller slide h',
which carries the rollers h, h, actuated by the cam g³ on the vertical shaft f, as
already described. The cam g in rotation gives an intermittent reciprocating
motion to the expansion valve e, which covers or closes the steam admission ports
to one end of the main slide valve d, and opens the ports at the other end, the
latter ports being closed in their turn to cut off the steam, and the former ports

page_text: opened to admit the steam. The point in the stroke at which the port is closed and
the steam cut off depends on the speed of the engine and horizontal position of the
spiral cam g³, as previously described.
In Figures 4, 5, and 6, the main valve rod d¹ is of the usual kind. The expan-
sion valves e, e, are shewn as constructed in two parts, each capable of moving in
guides on the main slide valve d, but at right angles to the motion of the latter.
The said expansion valves e, e, are each provided with two snugs or projections e,
the position of which with respect to the main slide valve rod d will be understood
by reference to Figure 5.
Between the said snugs e a finger or single toothed lever is placed. The
said toothed lever is attached to the rocking shaft, which is placed parallel with
the main valve rod d³, and is free to rock in bearings, which also form stuffing
boxes placed one at each end of the steam chest, as shewn. A lever is also
attached to the said rocking shaft , and is by means of the link ³ connected to
the roller slide h¹, actuated by the spiral cam g³ on the vertical spindle f, as before
described.
It will be seen that in both of the arrangements described, the expansion valve e
moves with the main slide valve d, except when it is operated upon by the cam g³,
and remains in any position on the valve d, into which it may have been brought
by the cam g³, and has no tendency to move therefrom. The expansion valve has
thus a minimum of motion, and is more durable, and requires less power to move it
than expansion valves of the usual construction.
In Figures 4, 5, and 6, the usual hand starting and reversing gear is shewn, con-
nected with the main slide valve d. To enable the said hand-starting gear to be
used when the engine is fitted with an expansion valve, I make the lower portion g
(or in some cases it may be the upper portion) of the cam g³ of the section, shewn
in Figure 6, having only one half the throw or eccentricity of the remaining
portion 93, so that when the governor slide c falls to its lowest position, as on
the stopping of the engine, the aforesaid portion g' of the cam 9 rises into the
same plane as the rollers h, h, on the roller slide h', and acting on one or other of
the said rollers moves the expansion valves e, e, into mid-position only, as shewn
in Figures 5 and 6, leaving the steam admission ports at one end of the main
slide valve d half open, and at the other end half closed, so that the steam can be
admitted at either end of the steam cylinder to move the engine either way by the
attendant moving the hand gear in the usual manner.
When the governor slide c rises above its lowest position as the speed of the
engine increases, the before-mentioned part g³ of the cam acts on the rollers, causing
the expansion valves e to cut the steam off alternately from each end of the cylinder
in the manner previously described.
Having now described the nature of my Invention, and the manner in which the
same is to be performed, I wish it to be understood that I do not limit myself to
the precise details herein described and illustrated, but I claim as my Invention of
improvements in steam engines,―
First. In a high speed governor, in which the balls or rollers act directly on the
counterpoise or slide, I claim the placing of the counterpoise or slide on the
governor spindle above the balls or rollers, for the purpose and substantially as
described, and illustrated in the accompanying Drawing.
Secondly. The combination of the spiral or helical cam, constructed as described,
and illustrated in the accompanying Drawing, with the rollers and roller slide or
their equivalents for actuating the expansion valves of steam engines in the manner
and substantially as described.
Thirdly. The combination of the two tubular rods d' and d³ with the expansion
valve rod e¹ and bell-crank lever k, for the purpose and substantially as described,
and illustrated in Figures 1, 2, and 3 of the accompanying Drawing.
Fourthly. The combination with the expansion valves of the single finger or toothed

page_text: lever and rocking shaft l' for the purpose and substantially as described, and illus-
trated in Figures 4, 5, and 6 of the accompanying Drawing.
In witness whereof, I, the said Daniel Longworth, have hereunto set my hand
and seal, this Twentieth day of June, in the year of our Lord One thousand
eight hundred and seventy-eight.
Witness,
JOSEPH HAMILTON,
2, Mayfair Villas,
Battersea,
London.
DANIEL LONGWORTH (LS.)