IMPROVEMENTS IN WORKING THE. VALVES OF STEAM AND OTHER ENGINES
Year: 1868

page_text: LETTERS PATENT to John Frederick Spencer, of Sunderland, in the
County of Durham, Consulting Engineer, for the Invention of
"IMPROVEMENTS IN WORKING THE. VALVES OF STEAM AND OTHER ENGINES."
Sealed the 10th November 1868, and dated the 18th May 1868.
the 18th May 1868.
I, JOHN FREDERICK SPENCER, of Sunderland, in the County of
Durham, Consulting Engineer, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN WORKING THE VALVES OF STEAM AND OTHER
ENGINES," to be as follows:
These improvements are applicable chiefly to Corliss double beat or
piston valve gear where separate ports are used for steam and exhaust,
and where the steam valve is opened by the motion of the usual

page_text: eccentric and closed by the action of a spring weight or pressure cylinder
in connection with detent or escapement gear.
In the first part of these improvements there are two radial arms,
discs, or segments, both placed to vibrate concentrically to the axis
of the steam valve rod or to the axis of a weigh shaft, giving motion
to the steam valve; one of these arms, discs, or segments is permanently
secured and connected to the usual eccentric and its rods, and the
other arm, disc, or segment is permanently connected to the steam
valve rod (or to the axis of a weigh shaft giving motion to the steam
valve) and also to the spring weight or piston which closes the steam
valve, and both arms, discs, or segments are connected together and
disengaged at the intervals of time necessary to regulate the cut-off
or expansion by detent or escapement gear in the usual or any
convenient way. By this improvement the rods connecting the steam
valve rods with the usual eccentric can be plain simple rods, and
the detent gear forms a portion of the radial arms, discs, or segments
previously described.
The second part of my improvements consists of the closing of steam
valves worked by detent gear by means of a piston working air-tight
in a cylinder and connected to a lever on the steam valve rod or to
a lever on a weigh shaft which gives motion to the steam valve rod,
which said piston is drawn out by the opening of the steam port and
thus forms a partial vacuum on the inner side of the said piston,
and by the pressure of the atmosphere on the outside of the said piston
closes the steam port when the detent releases the valve. By this
improvement the movement required to open the steam valve also
gives motion to the vacuum piston and creates the vacuum, and the
usual dash pot or air cushion can be formed by the vacuum piston
itself or by a separate cylinder and piston as preferred.
Inlet and outlet air valves are fitted to the vacuum cylinder to
regulate the amount of vacuum required, and, in cases where no
separate dash pot is used, also to regulate the amount of cushioning
required.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Frederick Spencer in the Great Seal Patent
Office on the 17th November 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
FREDERICK SPENCER, of Sunderland, in the County of Durham, Con-
sulting Engineer,.send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing, date the Eighteenth day of May, in the year
of our Lord One thousand eight hundred and sixty-eight, in the thirty-
first 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 exe-
cutors, 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
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 two Sheets of accompanying.
Drawings:-
These improvements are applicable chiefly to Corliss double beat or
piston valve gear, where separate ports are used for steam and exhaust,.
and where the steam valve is opened by the motion of the usual
eccentric and closed by the action of a spring weight or pressure cylinder
in connection with detent or escapement gear.

page_text: In the first of these improvements there are two radial arms, discs,
or segments, both placed to vibrate concentrically to the axis of
the steam valve rod or to the axis of a weigh shaft giving motion to
the steam valve; one of these arms, discs, or segments is permanently
secured and connected to the usual eccentric, and its rods, and the
other arm, disc, or segment is permanently connected to the steam
valve rod (or to the axis of a weigh shaft giving motion to the steam
valve) and also to the spring weight or piston which closes the steam
valve, and both arms, discs, or segments are connected together and
disengaged at the intervals of time necessary to regulate the cut-off
or expansion by detent or escapement gear in the usual or any
convenient way. By this improvement the rods connecting the steam
valve rods with the usual eccentric can be plain simple rods, and
the detent gear forms a portion of the radial arms, dises, or segments
previously described.
The second part of my improvements consists of the closing of steam
valves worked by detent gear by means of a piston working air-tight
in a cylinder and connected to a lever on the steam valve rod or to
a lever on a weigh shaft which gives motion to the steam valve rod,
which said piston is drawn out by the opening of the steam port and.
thus forms a partial vacuum on the inner side of the said piston,
and by the pressure of the atmosphere on the outside of the said piston
closes the steam port when the detent releases the valve. By this
improvement the movement required to open the steam valve also
gives motion to the vacuum piston and creates the vacuum, and the
usual dash pot or air cushion can be formed by the vacuum piston
itself or by a separate cylinder and piston as preferred.
Inlet and outlet air valves are fitted to the vacuum cylinder to
regulate the amount of vacuum required, and in cases where no
separate dash pot is used, also to regulate the amount of cushioning
required.
In the accompanying Drawings I have illustrated my Invention.
View 1, Sheet 1, is a side elevation, and View 2, Sheet 1, is a front
elevation of a part of a steam cylinder sufficient to illustrate the
improvements referred to in this Specification.
The detached views 1, 2, 3, 4, Sheet 2, are intended to shew two
distinct modes, among others, in which the improved arrangements can

page_text: be carried into actual practice, and in which the distinctive features of
my improvement are retained, namely, the united or combined action
of two distinct levers, segments, or discs acting radially from the centre
of the weigh shaft that gives motion to the slide which regulates the
admission of the steam to the steam cylinder, and such levers, segments,
or discs being connected together intermittently by ordinary detent or
escapement gear.
C, Sheet 1, 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 a steam port and slide valve with
lap and cover required 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 said faces are supposed to be curved and
the slide valve 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 Drawings
a valve commonly called the "Corliss" valve is supposed to be used;
G is a rod worked by an eccrentic or crank on the main crank shaft of
the engine or on a supplementary shaft driven by the crank shaft, and
the reciprocating motion of this rod causes the wrist plate H to vibrate
on a pin I. On the wrist plate 4 pins are fixed, from which motion is
given to 4 rods that are attached to the two admission and two exhaust
valves of each cylinder, only one of these pins K is shewn, which gives
motion to the escapement rod L which communicates with the weigh
shaft E and the admission slide valve through the radial escapement gear
hereafter described.
The improved radial escapement gear is shewn in detail in different
modifications in Sheet 2, Views 1, 2, 3, 4.
The radial action is illustrated in Sheet 2 by two distinct arrange-
ments, one of which is contained in lateral and transverse sectional
views 1, 2; La is a clip or ring connected by the pin M and rod L to
the wrist plate H (Sheet 1) and Ea is a disc keyed on to the weigh shaft
that gives motion to the admission slide, and it is also attached by the
eye S to the dash pot and spring that closes the steam port when the
escapement is in action, the clip La and disc Ea are connected inter-
mittently together by means of the detent bolt d, b, and trigger t, the

page_text: trigger being kept stationary by an adjustable rod a, r, the movement
of the clip La in the direction of the arrow (by an eccentric or crank
through the medium of the wrist plate) lifts the detent bolt clear
of the clip, and thus releases the disc E a, and allows it and the
admission valve to be acted on by the dash pot spring in the usual
way.
The front and side views 3 and 4, Sheet 2, represent another arrange-
ment of the detent in which a lever is used instead of the clip, and the
detent works on a pin instead of sliding in a slot.
Many other modifications of the detent gear may also be adopted
according to taste or circumstances without affecting the novelty of tho
radial action of the two distinct parts Ea and La. The amount of
expansion can in all cases be varied by providing for change of position
of the trigger, and this change can be effected by the governor or by
hand, acting on the rod a, .
Sections A and B, Sheet 1, shew the second part of my improvements..
In section A the piston p works air-tight in the cylinder, and when
drawn out by the action of the slide valve, a vacuum is formed in the
space S, S, sufficient to allow the atmosphere to act on the piston and
close the port when the detent is released; inlet and outlet air valves
are required to regulate the amount of vacuum and cushioning.
Section B shews the vacuum cylinder V, C, kept distinct from the
dash pot d, p, but in both cases the power to close the admission port
is obtained from atmospheric pressure, the vacuum to obtain which is
produced as before described by the motion of the weigh shaft E in
opening the admission port.
Having described the nature of this Invention, and the manner of
performing the same, I would observe that I do not confine myself to
any particular arrangement of detent or escapement gear required to
connect the before-mentioned radial arms, segment, discs, or levers, but
what I claim as my Invention to be protected by the herein-before in
part recited Letters Patent is,-
1st. Working the valves of steam or other engines by means of two
distinct radial arms, segments, dises, or levers, arranged and operated
in the manner herein shewn and described, or any mere modification of
the same.

page_text: 2nd. I claim the improved mode of closing such valves by means of
a vacuum obtained in the manner herein described.
In witness whereof, I, the said John Frederick Spencer, have
hereunto set my hand and seal, this Fourteenth day. of November,
in the year of our Lord One thousand eight hundred and sixty-
eight.
JOHN FREDERICK SPENCER. (L.S.)
Witness,
SAMUEL GEMMILL,
Engineer,
Gateshead-on-Tync.