IM- DATA WAY IN EXATVG A AmimED BY STEAM AD OTHER ELASTIC FLUI PROVISIONAL
Year: 1872

page_text: LETTERS PATENT to John William Melling, of Birkett Bank, Wigan,
in the County of Lancaster, Engineer, for the Invention of "IM-
DATA WAY IN EXATVG A AmimED BY STEAM AD OTHER ELASTIC FLUI
PROVISIONAL SPECIFICATION left by the said John William Melling
at the Office of the Commissioners of Patents, with his Petition,.
on the 18th July 1872.
I, JOHN WILLIAM MELLING, of Birkett Bank, Wigan, in the County..
of Lancaster, Engineer, do hereby declare the nature of the said Inven-
tion for "IMPROVEMENTS IN ENGINES ACTUATED BY STEAM OR OTHER ELASTIC
FLUID," to be as follows:-
My Invention consists, first, in actuating admission valves by the
combination of an adjustable lever, levers, or blocks, acted on by a cam
or cams, for the purpose of opening them, and a piston, plunger, or ram,
on which the steam can act, or a spring or weight for the purpose of
closing them. The lever or block is adjustable in a direction across the

page_text: axis of the cam, so that its end is reached by the largest part of the
cam at a sooner or later part of its revolution, as described in the
Specification of former Letters Patent granted to me on the 27th June
1871, No. 1681, which then allows the valve to be closed by the action
of the steam on the piston, or by the spring or weight. One or more
pistons, rams, or enlarged valve spindles may be used to each engine.
The levers or blocks and cams may have any desired number of steps to
suit the greatest variation in the load required. The position of the
adjustable levers or blocks may be regulated either by hand or by the
action of the governor. Where a cut-off plate on the back of the main
valve is used the piston may be arranged to move the plate either in the
same direction as the main valve or across it. The lever or block may
be so connected to the valve that it can be instantly disconnected either
by the action of the governor or by hand, so that no steam shall be
admitted to the cylinder. One way of accomplishing this is to connect
the valve rod to the lever through which it is moved by a pin or bar
that fits in a slot or guide in the lever against an abutment that projects
across the slot and is so fitted as to be readily withdrawn, or it may be
connected to the lever by a hook or strut that can be 'disengaged. When
desired the cut-off plate may also have its action suspended by being
held open altogether by any suitable mechanism, so as not to interfere
with the action of the main valve.
When applied to reversing engines I prefer to use a double block and
two sets of cams, one set to act on one part of the block when running
in one direction, and the others to act in the other direction.
The second part consists in the first place in using adjustable blocks
or levers both for opening and closing the valve, or the opening block
may be fixed and the closing one only be movable, the blocks to be
actuated by cams as before; secondly, in applying to winding or other
reversible engines (where Cornish or stamper valves are used) two
separate and adjustable lifters to each valve, one lifter and cam to act
when running in one direction, and the others to act in the other. The
lifters are so connected that when one is drawn out of reach of its cam
the other is brought within reach of the other cam. The steam lifters
and cams may have one, two, or more steps to extend the time during
which the steam shall be admitted.
The third part consists in the means for placing under the control of
the governor the adjustment of the position of the levers or blocks before

page_text: .
mentioned, or the regulation of the position of other expansion gears
by means of which the speed of the engine is controlled. This is
accomplished by imparting a reciprocating movement from some con-
venient part of the engine to a lever, frame, or slide, on which are
mounted two or more pawls that work over or alongside of and can gear
into the teeth of a wheel or rack that is in connection with the before-
mentioned levers, blocks, or other gear. On the side of the pawl frame
or slide is carried a guard, which fits under and keeps the ends of the
pawls out of gear with the wheel or rack; the guard is so carried that it
can be withdrawn from under one or other of the pawls; this is done by
mcans of two or more shoulders on it, by which its movements are
arrested by coming into contact with one or other of two catches that
are held by the governor and centred on some fixed centre; on the same
or other centre is a double lever, to which the governor rod is attached
and by which the ends of the catches are supported. The pawl frame or
slide in its movements carries along with it the guard which keeps the
pawls out of gear. When the engine is running at the required speed
the governor holds the catches so that the guard is not interfered with,
but when the engine is running either too fast or too slow one or other
of the catches is held in the path of the shoulders on the guard by which
its movement is arrested either during the whole or a portion of the
lever's vibration or the slide's motion; this allows one of the pawls to
fall into gear with and thus propel the wheel or rack in the required
direction. In the return stroke the movement of the guard is again
arrested before the lever or slide has completed its movement by coming
into contact with a fixed stop, and the pawl is again drawn on the guard
at the same time the guard is restored to its mid position. When the
governor lowers the other catch it causes the other pawl to be released,
so that the wheel or rack and its connections are moved in the opposite
direction. The guard may have any number of shoulders on it for the
purpose of arresting its movements, so as to allow the pawls to act
during a greater or less portion of their traverse.
In place of having a guard with projections carried on the catch
frame and moving along with it, a guard may be used on which are
formed two or more steps, along and up and down which the catches
can slide; the steps are to allow the catches to come into gear with the
toothed wheel sooner or later according to the position of the guard.
The guard may be pivotted on any convenient fixture, and its position

page_text: regulated by having attached to it a lever, one end of which is held by
the governor, and attached to and vibrating with the catch frame is a
plate with its inner edges formed into shoulders or steps; when the plate
is near the end of its stroke one or other of these shoulders comes into
contact with a projection on the lever that is held by the governor rod
and determines its position; or the stepped piece may be on the governor
lever.
In cases where the adjustment is effected by means of a wheel turned
by pawls, the range of its action may be limited, if desired, by pre-
venting the pawls, after they are released from the guard, from falling
into gear with the wheel, so that no further movement can be imparted
to the wheel in that direction. This is effected by forming on the wheel
spindle a screw on which is fitted a nut; when the wheel, is turned the
nut traverses along the spindle freely within the limits allowed, but
when those are reached it comes into contact with a pin or bolt carried
by the pawl frame, which when thrust, forward or drawn back causes
one or other of two stops to project and keep the pawl from acting on
the wheel.
Fourthly. In the mode of altering the position of eccentrics when
they are reversed by means of screws or racks. This is accomplished
when the eccentric is reversed by a screw by making the nut of the
screw into a toothed wheel that can be turned in either direction by
means of a bar or bars on which are two or more teeth set in opposite
directions. Part of the teeth are shaped to hold and turn the wheel in
one direction, the other part to turn it in the other. The bar or bars
may be held in contact with the wheel by means of a spring or springs,
and they are actuated by being attached to a sliding grooved bush or
collar that is moved by a forked lever in the usual way. When the
lever is moved from mid position to one side part of the teeth engage
in and turn the wheel, but the teeth are so shaped that when being
brought back they slip over without turning the wheel. When the
lever is moved from mid position to the other side the wheel is turned
in the opposite direction. If two bars are used the wheel will be turned
by both movements. Or in place of using a toothed bar to turn the
wheel the sliding, bush may be connected by means of a link to a lever
or pawl frame centred on the boss of or at the side of the wheel; on the
lever are centred two pawls set in opposite directions. At the side of
the wheel is fixed a guard, along which the ends of the pawls can slide;

page_text: the guard is of such a length that only one of the pawls can be in gear
at the same time. When the lever is moved from its mid position one
pawl gears into and turns the wheel, and the other is drawn on to the
guard clear of the wheel; if the lever is moved from its mid position in
the other direction the other pawl acts on the wheel to turn it the
opposite way. Or two pairs of pawls with their levers may be employed
so arranged that a pawl on one lever shall act on the wheel when the
forked reversing lever is moved from its mid position to the end, and a
pawl on the other lever shall act when the forked lever is being returned
to its mid position. In this case two guards are used, which may be
made movable, so that the pawls can be lifted out of gear while the
lever is in any position; this may be effected by coupling the two
guards to a rod that works through a hole in the guide upon which the
sliding bush fits; to the end of this rod are fitted two collars, with a
loose bush and forked lever in the ordinary way, or the guards may be
connected to a sliding bush. Also when two toothed bars are employed'
to turn the wheel the teeth on them may be released from it by having a
rod similar to the one before mentioned coupled to two wedge pieces,
that when required can, by means of the forked lever at the end of the
rod, be drawn between the boss of the wheel and the bars to force them
out of gear; when not required they are kept clear of the wheel by
suitable guides.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John William Mclling in the Great Seal Patent
Office on the 17th January 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
WILLIAM MELLING, of Birkett Bank, Wigan, in the County of Lan-"
caster, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eighteenth day of July, in the year of
our Lord One thousand eight hundred and seventy-two, in the thirty-
sixth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said John William Melling, Her special licence,
that I, the said John William Melling, my executors, administrators,
and assigns, or such others as I, the said John William Melling, my
:;

page_text: 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 ENGINES ACTUATED BY STEAM OR OTHER ELASTIC FLUID," upon the condition
(amongst others) that I, the said John William Melling, my executors or
administrators, by an instrument in writing under my, or their, or one
of 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 Seal Patent
Office within six calendar months next and immediately after the date
of the said Letters Patent.
NOW KNOW YE, that I, the said John William Melling, do hereby
declare the nature of my said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained
in and by the following Specification thereof, that is to say:-
The first part of my Invention consists in actuating admission valves
by the combination of an adjustable lever or levers, or blocks, acted
upon by a cam or cams for the purpose of opening them, and a piston
or pistons, or an enlarged valve spindle on which the steam acts, or a
spring or weight for the purpose of closing them.
On Sheet 1, Fig. 1 represents an arrangement of machinery for
actuating the main steam valves by means of a single cam acting upon
adjustable blocks. A is a 'horizontal cylinder; B, B, the chests for
the steam valves; and C, C, the chests for the exhaust valves. The
valves are moved by means of the wheel D, which is fixed on a shaft
driven by the engine; the wheel D gears into the wheels E and F;
at the side of the wheel E is the cam a, which acts on the adjust-
able blocks b and 6', fitting on the levers
and c¹; these levers may
' be connected to the pistons e and e¹, as shewn at d, or they may be
connected to them by catches similar to d¹; the ends of the pistons e, e¹,
are always open to the pressure of the steam in the chests B, and they
are connected to the valves f,f¹, by any suitable means.
The cam a
revolves in the direction of the arrow, and first opens the steam valve ƒ¹,
by operating through the adjustable block b', lever c¹, and its con-
nection with the piston e¹, which being forced in against the pressure
of the steam will, when the cam a has reached the end of the block b',

page_text: close the valve and force the lever c¹ back to its original position, the
length of time during which the steam is admitted depends on the
position of the block 6', which may be adjusted on the lever c¹, either
by hand or by the action of the governor, as will be hereafter described.
As the cam continues to rotate it acts in a similar manner on the
sliding block and valve f. The object of the catches d¹ is to prevent
damage in the case of a sudden removal of the whole or the greater
part of the load; the catch d³ is connected to the governor by the rod g
by which it is raised clear of the shoulder h on the lever c¹ so that
when raised no movement is communicated to the valve. When the
catches d¹ are used the ends of the pistons may be received by buffers or
cushions, as shewn at i, or when the links d are used the levers c
and c may be cushioned as shewn at j. The cam a and blocks b, b¹,
arc shewn with two steps, but any number may be used, and the shape
of the steps can be varied so as to cut off the steam either quicker or
slower.
The cam a and adjustable block 6 are similar to those described in the
Specification of Letters Patent granted to me on the Twenty-seventh day
of June One thousand eight hundred and seventy-one, Number 1681.
Figs. 2 and 3 represent a main valve which is supposed to be worked
in the ordinary manner, and a cut-off valve placed at right angles on the
back of the main valve, which is actuated as before described. In this
case two pairs of cams a and a¹ are employed acting upon a double block b,
this arrangement is particularly suitable for a winding or reversing
engine; the movement of the cut-off valve is the same for both ends of the
cylinder; this movement is effected by means of the two cams a, a, acting
on the upper end of the block b, when the engine is running in the
direction of the arrow, and by the cams a¹, a¹, acting on the lower end of
the block when running the reverse way; the blocks may be adjusted
by hand as hereafter described in reference to Figs. 6 and 7, or by any
other means. The block is connected to the valve f by the levers c,
rod d, elbow lever d², piston e, and slotted rod e¹, the steam acting on the
piston c would force it outwards and thus close the valve. The action
of the cut-off valve may be suspended by means of the hook g, which
catches on the pin h of the rod d; when the hook g is in the position
shown in Fig. 2 the cut-off valve would be in operation, but when it is
desired to suspend the action of the cut-off valve the inner shoulder of
the hook g must be allowed to fall on the pin h, which then prevents

page_text: the piston from being forced out by the steam and the cut-off valve is
held full open.
On Sheet 2, Fig. 4 represents an improved arrangement of machinery
for working the admission valves of engines in which Cornish or stamper
valves are used. A is a horizontal cylinder; B, the steam chest; G, G,
the ordinary valve levers; and H, the rocking shaft on which is fixed
the improved lifter k; to the lifter k are hinged the bars k³, and to these
bars are also hinged the struts k², the lower ends of which rest on
shoulders in the lifter. The lower ends of the struts ³ are connected
to the pin by the links A, and the pin fits in a horizontal slot in the
lifter k. To the bridle of the usual eccentric, or to any other convenient
part of the engine, is jointed the link m, which imparts a vibrating
motion to the lever m³, from which projects a stud m², this stud vibrates
within the frame n, supported by the link n¹, jointed to the elbow
lever n², the position of which is regulated by the governor or by hand
gear, the frame n is connected by the rod n³ to the pin l. When the
horizontal arm of the elbow lever n³ has raised the frame n until the
shoulders n' come in the path of the vibrating stud m³, then the frame n
is moved alternately to and fro, the action at first being slight but
gradually increasing as the frame rises, by this means the struts k² are
drawn off the shoulders of the lifter k; when the action of the frame n
is only slight the struts ³ remain on the shoulders of the lifter k for a
greater portion of the stroke, and consequently admit more steam than
when the frame is higher up and is moved earlier. When the strut
has been drawn off the shoulder of the lifter the bar ¹ being no longer
held up by the strut allows the valve to close. When the lifter descends
the strut and bar k¹ are held up by the bridle k*, and the strut
is again brought on to the shoulder of the lifter by the spring k³.
When the frame n is in the position shewn in the Drawing the stud m²
is at liberty to vibrate within the frame without touching it, and the
valves are then worked in the ordinary manner.
Fig. 5 represents a modification of the machinery shewn in Fig. 4.
In this arrangement H' are the ordinary valve lifters, and G are the
improved valve levers, to which are jointed the bars k², resting upon
the lifters H¹; to the bars k¹ are jointed the struts ², the upper
ends of which fit on shoulders on the levers G¹. On the rocking shaft H
is mounted the lever m³, from which projects the stud m³, which works
in the frame n connected by the link n' to an elbow lever similar to n² in

page_text: Fig. 4. The upper end of the lever m¹ has a slot in which are two studs
connected by links to the struts k². The rod; n³ is connected direct
to the eccentric bridle or to any other moving part of the engine, to give
a constant vibrating motion to the frame n. When the frame n is
down it vibrates without communicating motion to the lever m¹, but as
it is raised it acts on the struts ², as above described, the struts arc
replaced under the shoulders of the levers G¹ by the spring ³ acting on
the studs . This arrangement may be modified by keying the lever m¹
on the rocking shaft H, and connecting to it the movable frame n
which is raised and lowered as before described, the inside of the
frame n acts on the pins 7, which are connected to the struts /² by the
links k¹.
Figs. 6 and 7 represent a reversing lever and stand constructed
according to my improvements. In this instance the segmental guide o,
with notches to hold the reversing lever p in position, instead of being
fixed to the stand q as usual is supported on trunnions, so that the
reversing lever may have not only the usual lateral to-and-fro motion
between the segmental guide, but it can also be moved with the guide
into the position shewn in dotted lines lines in Fig. 6. The lever p is
connected by the link p' to the valve gear as usual, and the lever o³,
projecting from the segmental guide o is connected by the link o³ to
the frame n, shewn in Figs. 4 and 5. The lever, p. may be made to
move in both directions on the trunnions of the guide o, and employed
to adjust the blocks b, shewn in Fig. 2, or other kinds of expansion
gear.
On Sheet 3, Figs. 8 and 9, represent a mode of operating the cut-off
valve of an engine that is only required to run in one direction; the
cam a has two sets of steps which act on the three steps of the block b,
the parts a¹ and a² of the cam act on the parts 61 and 62 of the block
for admitting steam to the outer end of the cylinder, and the parts a³, a³,
act on the parts 62, 63, to admit steam to the other end. The double
lever c imparts motion to the rod d by means of the catch d', which is
centered in the levers at one end, and at the other abuts against the
bar d², which is free to slide in the slots as formed in the levers c. The
rod d' is connected to the governor for the purpose of lifting the catch
clear of the bar if the speed of the engine is greatly in excess, thus
cutting off the steam entirely, but at ordinary speeds the rod. head docs.
not reach the catch. When required the. hook g may be lowered, on
the pin g¹ to suspend the action of the cut-off valve by holding it open

page_text: altogether; if two cut-off valves are used, onc for each end of the
cylinder, with separate pistons to actuate them, only one step or set of
steps on the cam will be required. The movable block on the lever c
may either be adjusted by hand or by the action of the governor;
one way of accomplishing this is partially shewn at i, and will be
fully described hereafter. On the screwed spindle j is fitted a bevel
pinion k, which gears into another pinion on the shaft ; on the same
shaft is another wheel that can be turned round by either of two pawls
that are carried by the levers m, to these levers a reciprocating move-
ment is imparted from the eccentric bolt, as shewn, or in any other
convenient manner.
On Sheet 4, Figs. 10 and 11 represent an apparatus for regulating
the position of the adjustable blocks or levers before referred to, or the
position of other expansion gears, by means of which the speed of the
engine is controlled. a is the link through which a reciprocating
movement is given to the levers b, b', by which are carried the pawls
c, c. Fitting on the boss and at the side of the lever b is the guard
plate d, which when in mid position fits under the ends of the pawls
c, c¹; the guard is held against the side of the lever 6 by the spring d¹
in such manner that its position on the lever can be altered; on the
guard plate is fixed the plate e, on which are the projections or shoulders
c¹, e², e³, k¹ and k²; centred on some convenient fixed centre are the two
catches f,f, which overhang the plate o, these catches are supported
at one end by the double lever g, to which is coupled the governor rod h.
The toothed wheel i, to which movement is to be imparted by the
catches, is fixed on and turns the shaft ;, and through this moves the
before-mentioned adjustable blocks or other expansion gear. The levers
b, b', in their vibrations carry along with them the pawls c, c¹, and the
plates & and e, these plates are not interfered with so long as the engine
is running at the required speed, but if running either too fast or too
slow one or other of the catches f,f¹, is lowered into the path of one or
other of the shoulders e¹, e², or e³, and the plates e and d, are stopped
before the vibration of the pawls is completed and the pawl on that side
is allowed to fall into gear with and turn the wheel i partly round, in
the return movement the shoulder k¹or k³, comes into contact with
and is arrested by the fixed stop before the pawls have completed their
vibration, and the pawl is again drawn on to the guard d. If the speed
of the engine was too great and the action of the governor was to lower
the catch f, if only slightly in excess the catch would arrest the plate e

page_text: by means of the shoulder e', which would allow the pawl to fall into gcar
during only a very small portion of its movement, so that the wheel
would only be turned a very little, but if the speed was much in excess
the catch would be lowered to arrest the plates by one or other of the
shoulders e or e³, which would allow the pawl to fall into and turn the
wheel during a greater portion of its vibration, if the speed was too slow
the same operation would take place at the opposite side of the plates d
and e to turn the shaft in the opposite direction. The plate e may have
any desired number of shoulders. If required the action of the catches
c, c', on the wheel i may be limited. One mode of accomplishing this
is shewn in Figs. 12, 13, and 14. The shaft j has on it a screw thread
on which is fitted the nut m, this nut is prevented from turning by the
finger m', which may be made to shew, by means of an index, the point
at which steam is being cut off. On the side of the pawl lever b¹ is.
carried the bar n, which is kept in position by the spring n³, this bar
overhangs the flange of the nut m, leaving the required space for the
nut to travel without touching it, but when the bar is moved by the
nut in either 'direction it prevents the pawl, which up to that time had
been acting on the wheel i, from falling into gear; this is accomplished
by the part n on the bar n being moved in the path of the end of
the pawl c², or the part n³ being moved in the path of the end of the
pawl c. The pawls c³ and c³ are connected by a spring, as shewn in

page_text: "
Figs. 19, 20, and 21, represent three views of a mode of adjusting
the eccentric for actuating the expansion valve, this arrangement of
eccentric is a modification of that shewn in Figs. 1 and 2 of the Speci-
fication of my former Patent above referred to, the eccentric is
provided with internal teeth into which the worm d gears, to this worm
is fixed the pinion & which is driven by the pinion & attached to the
bevel pinion d³. On the shaft e are two pinions e¹ and e², which are
put into gear with the pinion d³ by the lever f, the shaft e is supported
in a bearing in the lever f, and in a bearing in the crank shaft. When
the engine is working at its proper speed both the pinions e¹ and e are
out of gear and are held in that position by a pin f passing through the
lever and the standard f¹, but when an alteration in the speed is
required the screw f² is tightened on to the bearing of the shaft e to
prevent the shaft revolving, and the pin f³ is withdrawn to allow either
of the pinions e¹ or e² to be put into gear with the pinion d³, which then
communicates motion to the pinions d² and d³ and worm d to alter the
position of the eccentric in the direction required. If an alteration is
required in the position of the eccentric when the engine is standing,
the screw is slackened and the shaft e is turned by means of the hand
wheel e. The shaft e, with the pinions e¹, e², and hand wheel e³, and the
lever f, may be used for reversing or adjusting the eccentric for working
the main valve by making the boss of the wheel in which the pinions e²
and e² gear into a nut fitting on the regulating screw of the eccentric.
Having thus stated the nature and particulars of my Invention, I
wish it to be understood that I claim the various improvements shewn
and described when used separately, or when any parts thereof are used
in combination.
And I also claim the application of parts thereof to valve motions and
cut-off gears of other descriptions.
In witness whereof, I, the said John William Melling, have hereto
set my hand and seal, this Sixteenth day of January One
thousand eight hundred and seventy-three.
JOHN WILLIAM MELING (L.S.)
^