IMPROVEMENTS IN REGULATING AND WORKING THE VALVES OF STEAM AND OTHER ENGINES."
Year: 1865

page_text: LETTERS PATENT to John Frederick Spencer, of Newcastle-upon-Tyne,
Consulting Engineer, for the Invention of "IMPROVEMENTS IN REGULATING
AND WORKING THE VALVES OF STEAM AND OTHER ENGINES."
PROVISIONAL SPECIFICATION left by the said John Frederick Spencer at
the Office of the Commissioners of Patents, with his Petition, on the
11th January 1865.
I, JOHN FREDERICK SPENCER, of Newcastle-on-Tyne, Consulting Engineer,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
REGULATING AND WORKING THE VALVES OF STEAM AND OTHER ENGINES," to be as
follows:-
To obtain the economical use of steam, air, or gas as a motive power in an
engine it is desirable to separate and keep distinct the valves which admit.
the steam from those which release the steam, and this Invention refers only
to engines fitted with such separate valves, and in all cases where this Inven-
tion is available the admission valves must be closed or returned home after
being opened by a spring or springs, or weights, the eccentric being only
available for opening and not closing the admission valves. To facilitate
explanations of this class of valve gear it will hereafter be described.. as
"escapement" valvo gear, but the valves themselves may be of any approved
kind requiring slight power to close them when open..

page_text: The immediate object of this Invention is to economize steam, air, or gas
as motive power by introducing into more general use distinct and separate
admission valves and improved escapement gear, and with such valves and
gear materially increasing the speed of piston. The Invention consists of―
First, an arrangement in which two spring plates or clips are connected at
one end to a pin of a lever or wrist plate secured to a weigh shaft, such weigh
shaft having a reciprocating motion produced by an eccentric; the other end
of the spring plates or clips have inside projections which clip hold of or gear
into other projections on a moveable block attached to the spindle or lever of
the admission valve, and as usual in this class of escapement gear the closing
of the admission valves takes place by the action of a trigger or toe, which
by its attachment to some fixed point, and by the motion of the eccentric and
clips on opening the admission valves, releases or throws out of gear at the
same moment both of the spring plates or clips, and the admission port is
suddenly closed as usual by a spring or springs. The advantages secured by
this arrangement are (1) simplicity of construction.; (2) reduction of risk, as
in the event of one clip giving way the other one would act until a convenient
opportunity for repair; (3) increased sensitiveness in releasing, as two clips
need not be so deep in gear as when one is used, and will therefore be more
quickly tripped or disengaged by the trigger or toe; also (4) these double
spring plates or clips can be used in any position without their action being
impaired. The arrangement described admits of many modifications in detail
without affecting the principle of the Invention or lessening the advantages
before described. Each admission valve requires a pair of the spring plates
or clips, but both pairs of clips may be and generally are attached to levers or
a wrist plate attached to one and the same weigh shaft vibrating by the action
of one eccentric.
Secondly, the introduction and application of two or more adinission ports
or passages in each end of cylinders working with slide valves that are
opened and closed with escapement gear; by this improvement the tripping
gear described in the first part of this Invention is rendered still more
efficient, as the maximum movement of the valve spindles or levers may be
much less than when one port is used as usual, and the less the motion
of the valve spindles or levers the more certain is the action of the
escapement gear, and the engines can be worked at an increased number of
revolutions.
Thirdly, attaching the piston of a small cylinder in which a pressure of steam,
air, gas, or water is introduced to the spindle or lever of the admission valves

page_text: when worked by escapement gear, so that such valves are closed by such
pressure instead of by the action of weights or springs.
Fourthly, in the arrangement of springs for closing the admission valves
worked by escapement gear, the introduction of a spiral steel or india-rubber
ring, spring, or springs acting directly on the back of a piston used in a
cylinder as an air cushion to reduce the shock of the closing of the admission
valves, it being usual to have such air piston attached directly by a rod to the
spindle or levers of the admission valves; such air piston and its cylinder is
usually termed the dash pot. This part of this Invention is an improvement
on the present mode of keeping the springs distinct from the dash pots, the
spring or springs being placed between two dash pots and connected to them
by pins, keys, or bolts, in which case a failure of the spring or springs disables
both admission valves instead of one only as in the improved arrangement
previously described.
Fifthly, forming one central chamber fixed midway to the cylinder or engine
framing and arranged to contain the two air pistons or dash pots, and the
recoil springs, such chamber to be equally divided by a central diaphragm
and to have moveable ends or covers for ready access to the dash-pot pistons
and recoil springs of each admission valve. By this improved arrangement
simplicity and cheapness of construction are ensured,
Finally, with reference to the several parts of this Invention, all having
reference to improvements in escapement valve gear, it is to be understood
that to the cylinder of every engine there are two admission valves, two
pairs of spring plates or clips, two dash-pot pistons, and two springs or sets of
springs for closing the admission valves when the escapement clips are disen-
gaged or thrown out of gear by the action of the triggers or toes before
referred to. It has not been considered necessary to refer to the release
or exhaust valves in the preceding as they are separate and distinct from the
admission valves, one eccentric however can work the four valves.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eleventh day of January, in the year of our Lord
One thousand eight hundred and sixty-five, in the twenty-eighth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said John Frederick Spencer, Her special licence that I, the said
John Frederick Spencer, my executors, administrators, and assigns, or such
others as I, the said John Frederick Spencer, my 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 REGULATING AND WORKING THE VALVES OF STEAM AND
OTHER ENGINES," upon the condition, amongst others, that. I, the said John
Frederick Spencer, 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 Frederick Spencer, 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 statement, and on reference to the accompanying Drawings,
that is to say:
The immediate object of this Invention is to economize steam, air, or gas
as motive power, by introducing into more general use distinct and separate
admission valves and improved escapement gear, and with such valves and
gear materially increasing the speed of piston. The Invention consists of-
First, an arrangement in which two spring plates or clips are connected at
one end to a pin of a lever or wrist plate secured to a weigh shaft, such
weigh shaft having a reciprocating motion produced by an eccentric; the
other end of the spring plates or clips have inside projections which clip hold
of or gear into other projections on a moveable block attached to the spindle
or lever of the admission valve, and as usual in this class of escapement gear
the closing of the admission valves takes place by the action of a trigger or
toe, which by its attachment to some fixed point and by the motion of the
eccentric and clips in opening the admission valves releases or throws out of
gear at the same moment both of the spring plates or clips, and the admission
port is suddenly closed as usual by a spring or springs. The advantages

page_text: secured by this arrangement are (1) simplicity of construction; (2) reduction
of risk, as in the event of one clip giving way the other one would act until
a convenient opportunity for repair; (3) increased sensitiveness in releasing
as two clips need not be so deep in gear as when one is used, and will there-
fore be more quickly tripped or disengaged by the trigger or toe; also (4)
these double spring plates or clips can be used in any position without their
action being impaired. The arrangement described admits of many modifica-.
tions in detail without affecting the principle of the Invention or lessening
the advantages before described. Each admission valve requires a pair of
the spring plates or clips, but both pairs of clips may be and generally aro
attached to levers or a wrist plate attached to one and the same weigh shaft
vibrating by the action of one eccentric.
Secondly, the introduction and application of two or more admission ports
or passages in each end of cylinders working with slide valves that are
opened and closed with escapement gear; by this improvement the tripping
gear described in the first part of this Invention is rendered still more
efficient as the maximum movement of the valve spindles or levers may
be much less than when one port is used as usual, and the less the motion
of the valve spindles or levers the more certain is the action of the
escapement gear, and the engines can be worked at an increased number of
revolutions.
Thirdly, attaching the piston of a small cylinder in which a pressure of
steam, air, gas, or water is introduced to the spindle or lever of the admission
valves when worked by escapement gear, so that such valves are closed by.
such pressure instead of by the action of weights or springs.
Fourthly, in the arrangement of springs for closing the admission valves
worked by escapement gear, the introduction of a spiral steel or india-rubber
ring, spring, or springs acting directly on the back of a piston used in a cylinder
as an air cushion to reduce the shock in the closing of the admission valves,
it being usual to have such air piston attached directly by a rod to the spindle
or levers of the admission valves, such air piston and its cylinder is usually.
termed the dash pot. This part of this Invention is an improvement on the
present mode of keeping the springs distinct from the dash pots, the spring or
springs being placed between two dash pots and connected to them by pins,
keys, or bolts, in which case a failure of the spring or springs disables both
admission valves instead of one only, as in the improved arrangement previously..
described.
Fifthly, forming one central chamber fixed midway to the cylinder or engine
framing and arranged to contain the two air pistons and dash pots and the.

page_text: recoil springs, such chamber to be equally divided by a central diaphram and
to have moveable ends or covers for ready access to the dash-pot pistons and
recoil springs of each admission valve. By this improved arrangement
simplicity and cheapness of construction are ensured.
Finally, with reference to the several parts of this Invention, all having
reference to improvements in escapement valve gear, it is to be understood
that to the cylinder of every engine there are two admission valves, two pairs
of spring plates or clips, two dash-pot pistons, and two springs or sets of
springs for closing the admission valves when the escapemen clips are disen-
gaged or thrown out of gear by the action of the triggers or toes before
referred to. It has not been considered necessary to refer to the release or
exhaust valves in the preceding as they are separate and distinct from the
admission valves; one eccentric however can work the four valves.
.
In the accompanying Drawing I have illustrated my Invention.
Views 1 and 2 are front and side elevation of a part of a steam cylinder
sufficient to shew the improvements in valve gear referred to in this Speci-
fication, and views 3 and 4 are intended to shew the improved escapement
rod by itself; C is the cylinder of a steam engine, a portion only of which is
shewn, and such cylinder may be vertical, horizontal, or inclined without
impairing the usefulness of the improved valve gear; D is a portion of the
valve chest in which is one of the ordinary steam admission ports and a plain
slide valve made to cover the port with sufficient lap to prevent leakage and
to suit the action of the valve. The port and slide faces may be flat or curved
according to the plan adopted to move the valve; in the Drawing the port
and valve faces are curved, the slide valve is worked by drivers on a weigh
shaft E, passing through a stuffing box F; this weigh shaft E might give
motion to any other kind of valve which requires little power to move it, but
in the present illustration a valve commonly called the "Corliss" valve is
supposed to be used; G is a rod worked by an eccentric or crank on the main
crank shaft or on a supplementary. shaft driven by the crank shaft, and the
reciprocating motion of this rod causes the disc plate H to vibrate on a pin I.
On the disc plate are four pins K, K, two of which only are shewn, and one
of these gives, motion to the escapement rod L, which is attached by a pin M
and lever N to the weigh shaft E, which gives motion to the slide for admitting
steam to the cylinder. The escapement rod consists of two principal and
distinct parts La and Lb, one of which La is always connected to the
pin K on the disc plate H, and the other Lb to the pin M. O, O, are two
steel spring clips bolted to that part of the escapement rod La which is
attached to the pin K, and these spring clips are connected to that part of the

page_text: escapement rod Lb which is attached to the pin M by the grip of the pro-
jecting edges of hardened steel P, P, P, P; Q is a lever, toe piece, or trigger
working on the pin R, and connected by rods, &c. to an adjustable handle
accessible to the engineer in charge. When the engine is started, and the
escapement rod is in gear, as shewn in the Drawing, the motion of the disc
plate and escapement rod in the direction of the arrows brings the trigger Q
in contact with the insides of the spring clips O, O, and throws them out of
gear, and the admission valve is instantly closed by the action of a spring or
weights acting on the lever S and weigh shaft E, and the time when the clips
are disengaged and the admission valve is closed can be varied at pleasure by
the relative position of the trigger lever, which is held in any position at the
pleasure of the engineer in charge, or the trigger may be connected to a
governor to regulate the speed of the engines by varying the amount of the
steam admitted to the engines. The two parts of the escapement rod before
described are shewn in the Drawing as guided in the same line of motion by
a guide rod and bush.
In views 3 and 4 the escapement rod is shewn disengaged, the steel spring
clips being pressed outwards by the pressure of the toe or trigger, and allowing
the parts La and Lb of the escapement rod to be separated by the closing
action of the slide valve. Escapement valve gear such as used in pumping
engines is so well known to engineers that any further description of the first
part of the Invention is considered unnecessary. Many modifications of
detail may be made without affecting the Invention of the double clip
escapement.
The second part of the Invention requires no Drawing to explain it, and is
limited to cylinders working with slide valves only.
In explanation of the third, fourth, and fifth portions of the Invention, the
piston and cylinder in which the pressure of air, steam, gas, or water is used
to act on the lever S and close the admission valve is shewn at T, and these
cylinders (one to each admission valve) may be supplied with steam, air, &c.
from any convenient source.
To illustrate the improvements in the springs and air pistons for effecting
certainly and yet gently the closing of the admission valves a volute or spiral
spring is shewn at U, U; W is the air piston, X is the central chamber
described in the fifth part of the Invention, and Y is the central diaphram.
The Drawing clearly shews the improved arrangement of air and steam
pistons and springs in one central chamber bolted to the cylinder and used
in connection with escapement gear. In the Drawing only one escapement
rud is shewn, and the exhaust valves may be and commonly are worked from

page_text: pins on that half of the disc not shewn, so that one excentric rod can actuate
the four valves of one cylinder.
In witness whereof, I, the said John Frederick Spencer, have hereunto
set my hand and seal, this Twenty-fourth day of June One thousand
eight hundred and sixty-five.
JOHN FREDERICK SPENCER. (L.S.)
Witness,
JOSEPH E. L. BLACK,
Merchant,
Newcastle-on-Tyne.