IMPROVEMENTS IN MOTIVE-POWER ENGINES.
Year: 1875

page_text: LETTERS PATENT to James Wall O'Toole, of Cork, Ireland, Engineer,
for the Invention of "IMPROVEMENTS IN MOTIVE-POWER ENGINES.'
Sealed the 10th March 1876, and dated the 16th November 1875.
PROVISIONAL SPECIFICATION left by the said James Wall O'Toole
at the Office of the Commissioners of Patents, with his Petition,
on the 16th November 1875.
I, JAMES WALL O'TOOLE, of Cork, Ireland, Engineer, do. hereby
declare the nature of my said Invention for "IMPROVEMENTS IN MOTIVE-
POWER ENGINES," to be as follows:-
My Invention relates to the valve gear of engines generally, and has
for its object enabling the engine to be reversed with facility even
when running with full steam, and that without danger to the man in
charge, providing means of varying the degree of expansion to any
required extent, and also obtaining an equal lead whatever may be the
stroke of the valve.
In carrying out my Invention as applied to a double-cylinder steam

page_text: each of which forms the segment of a ring of the radius herein-after
mentioned, and is made of a length suited to the throw of the eccentric
and the travel of valve required.
On the front face of each segmental lever a segmental groove is cut
for the full length, and in the centre of the back face is a journal upon
which the lever swings. On the back face there is also placed a stud at
a suitable distance from the centre of the journal before mentioned to
which the eccentric rod is attached, whereby the lever is moved
backwards and forwards. To the segmental groove formed in the front
face of the segmental lever there is fitted a slide block carrying a pin
to which is attached one end of a connecting rod, the other end of which
is connected to a slide guide for the valve spindle outside the end of
this connecting rod, which is attached to the slide block in the groove of
the segmental lever, and on the same pin there is provided a second
slide block which works in horizontal guide ways formed in a vertical
slide. This slide which works up and down along suitable guides has
three functions, viz.,-
1st. By it the movements of the segmental lever given to the con-
necting rod and transferred to the valve spindle slide guide are made
equal from the centre both backwards and forwards, thus insuring
equal steam at each side of the piston.
2nd. It is employed in reversing the engine, being connected to a
lever on the reversing shaft by means of a link, whereby the movements
of the reversing shaft are communicated to it.
It is obvious that as the vertical slide is connected to the slide block 2
in the groove of the segmental lever and the connecting rod of the
valve spindle slide guide any movement of the vertical slide in its guides
will be communicated to the slide block in the groove of the segmental
lever, and thence to the valve spindle slide guide by its connecting rod,
such connecting rod being the radius of the segmental lever. Let it a
now be assumed that the crank is at half stroke and the engine is
running forward with full steam, the eccentric will then be at full
stroke, and the segmental lever will be also at full stroke, and as the
engine is running forward with full steam the reversing lever will be
full forward, but as the movements of the reversing shaft regulate those 3
of the vertical slide it follows that the vertical slide will be at the lowest
point in its guides or as it may be termed at full stroke, consequently

page_text: the valve spindle slide guide must be also at full stroke, and the forward
steam port will be fully open.
In order to illustrate how this steam port may be closed and the port
at the other side of the piston opened without changing the position of
the crank, let it now be assumed that the reversing lever is moved to
half way back, its position will be then central, consequently the vertical
slide will also be in a central position in the segmental lever and the
valve will be at half stroke. If now the reversing lever be moved from
this position to that of full back, the position of the other parts will also
be that of full back, consequently the steam port at the other side of
piston will be fully open. In describing these operations the engine has
been assumed to be at rest, but it may be reversed with full steam on
and running at its greatest speed with equal facility and safety to the
driver.
3rd. The third function of the vertical slide is to cause the engine to
work expansively, which result is obtained by placing the reversing
lever in a position suited to the degree of expansion required.
The valve spindle slide guide and its connections are arranged in the
following manner in order to obtain an equal lead of the slide valves.
In the guide works a slide block to which the valve. spindle is made
fast, so that any movement of the block will be given to the valvo
spindle. To the slide block there is also attached one arm of a bell-
crank lever having its fulcrum on a bracket carried on the guide, the
other arm of which lever is attached to a link connected to one end of
another bell-crank lever working on a fixed centre. The other arm of
the second bell-crank lever is attached by means of a connecting rod to
a stud on the back of the segmental lever placed at such a distance from
the centre of the journal as will move the bell-crank lever attached to
the bracket on the valve spindle slide guide the proper distance, so that
the valve spindle may move the slide valve the lap and lead in advance
of whatever distance it may be moved by the segmental lever, thus
securing an equal lead of the slide valve in whichever way it may
necessary to work the engines.
be
When the Invention is applied to locomotive engines two eccentrics
only one will be required in lieu of four as in the ordinary construction.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,'
filed by the said James Wall O'Toole in the Great Seal Patent
Office on the 13th May 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
WALL O'TOOLE, of Cork, Ireland, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixteenth day of November, in the year
of our Lord One thousand eight hundred and seventy-five, in the thirty-
ninth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said James Wall O'Toole, Her special
license that I, the said James Wall O'Toole, my executors, admini-
strators, and assigns, or such others as I, the said James Wall O'Toole,
my executors, administrators, or 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 MOTIVE-POWER ENGINES," upon the condition (amongst
others) that I, the said James Wall O'Toole, my executors or admini-
strators, by an instrument in writing under my hand and seal, 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 James Wall O'Toole, 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, reference being had to the accompanying
Drawings, and to the letters and figures marked thereon, that is to
say:―
My said Invention relates to the valve gear of engines generally, and
has for its object enabling the engine to be reversed with facility even
when running with full steam without danger to the man in charge,
and providing means of varying the degree of expansion to any required

page_text: Figure 1 of the accompanying Sheet of Drawings is a horizontal
section of a pair of locomotive steam engines with my improved
construction and arrangement of valve gear applied thereto as an
example of a mode of carrying out my Invention; Figure 2 is a longi-
țudinal vertical section of the same taken along the line 1, 2, in
Figure 1; and Figure 3 is a similar section taken along the line 3, 4,
Figure 1. The remainder of the Figures are details which will be
herein-after referred to.
In the following description of the pair of steam engines illustrated
by my Drawings I shall refer to one set of apparatus only, it being
understood that the corresponding parts of the other set of apparatus
are indicated by the same letters of reference with the addition of a
dash.
A is a steam cylinder provided with the usual steam inlet ports a, b,
and exhaust port c and with a piston B, which latter is connected by
its rod C, and a connecting rod (not shewn in my Drawings) with the
crank D on the driving shaft E; F is a metal frame secured by any
suitable means to the bed plate or other couvenient part of the engine
(about midway between the cylinder A and the shaft E) to which frame
there is suspended a segmental lever or link G, shewn detached in front
and back elevation respectively in Figures 4 and 5, and in sectional
clevation and horizontal section respectively in Figures 6 and 7. The
lever G is made of a length suited to the travel of the valve H and
the throw of the eccentric I, and is provided at or about the centre of
the back face with a journal K upon which it is caused to oscillate in
a bearing L fitted to or formed on the frame F, and at a suitable
distance from the journal K there is fitted a stud M, to which the
eccentric rod N is attached, whereby the segmental lever G is caused
to oscillate or move backwards and forwards when the shaft E rotates.
In the front face of the segmental lever G there is formed a segmento-
annular groove d extending throughout its entire length, in which
groove there is fitted a slide block e carrying a pin f, to which one end
of the connecting rod O is attached, the opposite end of such rod being
connected to the slide guide P for the spindle Q of the valve H. The
groove d is struck from a radius equal to the length of the rod O, which
latter dimension is to be determined according to circumstances, as
will be well understood. The pin ƒ also carries another slide block g
fitted to work horizontally in guide ways formed in a sliding block h

page_text: arranged to work up and down vertical guides formed in or upon the
frame F. Upon motion being imparted to the segmental lever G by
the eccentric I (which is keyed fast on the shaft E) such motion will be
transmitted through the intervention of the connecting rod O to the
valve spindle guide P, and the slide block g being caused to maintain a
rectilineal position by reason of the sliding block h and the groove d in
the segmental lever G, providing the requisite play to admit of such lever
describing its arc, the movements imparted to the connecting rod O are
made equal from the centre both backwards and forwards, and equal
steam is obtained at both sides of the piston. In the guide P there is
fitted a slide block i to which is attached one arm k of a bell-crank
lever having its fulcrum on a bracket m carried on the guide P the
other arm n of which lever is attached to a link o connected to one.
arm P of another bell-crank lever working on a fixed centre q. The
other arm (Figure 3) of the second bell-crank lever is attached by
means of a connecting rod s¹ to a stud t on the back face of the segmental
lever G¹, at such a distance from the centre of the journal K¹as will
move the bell-crank lever the proper distance, so that the valve
spindle Q may move the slide valve H the lap and lead in advance of
whatever distance it may be moved by the segmental lever G, thus.
securing an equal lead of the slide valve in whichever way it may.
be necessary to work the engines. The slide block his connected'
to the reversing shaft R by means of a link S, one end of which is
jointed to the slide block h, whilst its opposite end is attached to
a lever T keyed on the shaft R, the latter being provided with a lever U
by means of which the reversing of the engine is effected.
It is obvious that as the vertical slide h is connected to the slide
block e in the groove of the segmental lever and the connecting rod O of
the valve spindle slide guide P, any movement by the reversing lever of:
the vertical slide h in its guides will be communicated to the slide
block e in the groove d of the segmental lever G, and thence to the
valve spindle slide guide P by its connection rod O. Let it now be
assumed that the crank D', Figures 1 and 3, is at half stroke and the
engine is running forward with full steam, the eccentric T¹ is at full
stroke and the segmental lever G¹ is also at full stroke, all as shewn in
Figures 1 and 3. As therefore the engine is running forward with full
steam the reversing lever U is full forward, but as the movements of the
reversing shaft R regulate those of the vertical slide h it follows that the

page_text: vertical slide is at the highest point in its guides, or as it may be
termed at full stroke; consequently the valve spindle slide guide P¹
must be also at full stroke and the forward steam port port 6' fully open.
In order to illustrate how this steam port may be closed and the
port a at the other side of the piston opened without changing the
position of the crank, let it now be assumed that the reversing lever U
is moved to half way back so as to bring the lever T into the position
shewn by the dotted lines in Figure 3, its position will be then central,
consequently the vertical slide h will also be in a central position in
the segmental lever G' and the valve H' will be at half stroke. If now
the reversing lever U be moved from this position to that of full back, as
indicated by the red line in Figure 3, the position of the other parts will
also be that of full back, consequently the steam port a¹ at the other
side of the piston will be fully open. In describing these operations the
engine has been assumed to be at rest, but it may be reversed with full:
steam on and running at its greatest speed.
When the engine is working at full speed or at any other speed the
segmental lever G is also in motion, and as the slide blocks e and g are
connected by the same pin f they will both move vertically when the
slide h is acted upon by means of the reversing lever in the act of
reversing the engine. The block e in addition to its vertical motion is
also caused to move horizontally in the slide block h, and thereby the
liability is obviated of any shock being transmitted to the driver who is
enabled to reverse the engine with safety and facility.
When it is required to work the engine expansively this result may
be accomplished by adjusting by the act of operating the reversing
lever U the slide h to an intermediate position in either direction,
according to the degree of expansion desired and the direction in which
the engine is required to work.
When the valves of a pair of engines are arranged to work side by
side, as illustrated by my Drawings, two eccentrics only will be necessary
for working the valves of both of the cylinders in lieu of four as in
locomotive engines of the usual construction.
I prefer to arrange the apparatus in such a manner that the con-
necting rod s¹ attached to the left-hand segmental lever G¹ is connected
to the bell crank for working the slide block attached to the spindles Q
of the valve H of the right-hand cylinder A, and the connecting rod s
0

page_text: attached to the right-hand segmental lever G is connected to the bell
crank for working the slide block attached to the spindle Q¹ of the
valve H of the left-hand cylinder A', as shewn.
In cases where it would be inconvenient to work the bell cranks from
the segmental levers G, G', they may be worked by means of eccentrics
keyed on the shaft E, as shewn in Figure 8, or they may be actuated by
any other suitable attachment connected to any convenient working
part of the engine. If desired in lieu of forming the groove in the
levers G, G¹, the slide blocks e¹, may be grooved and fitted to slide
along the levers, the latter being made of a shape corresponding to the
groove of the slide blocks.
Having now described and particularly ascertained the nature of my
said Invention, and the manner in which the same is, or may be used,
or carried into effect, I would observe in conclusion that what I consider
to be novel and original, and therefore claim as the Invention secured
to me by the herein-before in part recited Letters Patent is,-
0
First. The employment in the valve gear of motive power engines, of
an oscillating segmental lever or link, or of an oscillating lever or link
having a segmento-annular groove or guideways in combination with a
sliding block connected with the distributing valve of the engine, and
working in or on the oscillating segmental lever or link or its segmento-
annular groove or guideways when arranged and operating substantially
in the manner and for the purpose herein-before described.
Secondly. The combination with the sliding block working in or
on a segmental oscillating lever or link, or in or on a segmento-annular
groove or guideways formed in or on an oscillating lever or link, as
herein set forth, of a vertical slide for the purpose of ensuring an equal
motion of the valve connecting rod in both directions, and facilitating
the adjustment of the slide block for reversing the engine and varying
the expansion, substantially as herein-before described.
Thirdly. Obtaining the permanent or constant amount or portion of
the stroke of the distributing valve by the aid of an oscillating lever
mounted upon a moving fulcrum carried by connections which impart
the variable amount or portion of the stroke of the valve, all arranged
and operating substantially as and for the purpose herein-before
described.

page_text: Fourthly. The combination with the reversing lever U of the vertical
slide and horizontal slide 9, of the slide block ¸e and the oscillating
segmento-annularly grooved lever G, the pin f, connecting rod O, and
valve spindle guide P, the whole arranged and operating in connection
with the distributing välve, substantially in the manner and for the
purpose herein-before described and as illustrated by my Drawings.
In witness whereof, I, the said James Wall O'Toole, have to this
my Specification set my hand and seal, this Eighth day of May,
One thousand eight hundred and seventy-six.