IMPROVEMENTS IN STEAM AND OTHER ENGINES
Year: 1859

page_text: LETTERS PATENT to John Elder, of Glasgow, Engineer, for the Invention
of "IMPROVEMENTS IN STEAM AND OTHER ENGINES."
Sealed the 11th April 1860, and dated the 15th October 1859.
PROVISIONAL SPECIFICATION left by the said John Elder at the
Office of the Commissioners of Patents, with his Petition, on the 15th
October 1859.
I, JOHN ELDER,. of Glasgow, Engineer, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN STEAM AND OTHER ENGINES," to be as
follows:
This Invention relates to a novel mode of arranging and working the valve
gear and valves of steam and other engines, by which the alternate admission
and escape of steam, air, &c. is regulated, and it consists in substituting for
the ordinary modes or methods in use for actuating the eccentric and valve
gear, an arrangement, as herein-after described in conjunction with either a
single or double port face, or seat and slide, valve chest, a novel arrangement
of wheel gearing for producing the desired motion of the slides.
Instead of placing the eccentric or eccentrics upon the crank shaft or main
.shaft of the engine, and communicating the motion of the eccentric by means
of a rod connected to the eccentric strap at one end, whilst the other end is
either connacted direct to the slide valve rod; or to the spanner or lever of a
weigh shaft, which in turn communicates the requisite. alternate action or
motion to the slide valve, and instead also.of placing the eccentrics upon inde-
pendent shafts driven uniformly and at the same speed as the crank shaft or

page_text: main shaft, such motion being communicated to such eccentrics by means of
spur gearing; and instead also of the various contrivances for actuating slide
valves, by means of cams of divers shapes, tappets, and such like mechanical
means, I effect any desirable amount of pause, slowing, or cessation of motion
in the travel of the slide valves by the employment of oval or eccentric wheel
gearing for giving motion to the ordinary eccentric or eccentrics, the major
and minor axes of these oval or eccentric wheels being suitably proportioned
to impart the requisite amount of action or motion to the slide valves at the
proper times by the continuous and uniform rotation of the main or crank
shaft upon which the oval or eccentric driving wheel is fixed, whilst the corre-
sponding wheel into which it takes, and which it drives or rotates, is fitted upon
the shaft carrying the ordinary eccentric arrangement connected with the
slide valve..
Now although I propose to apply one or more oval or eccentric driven
wheels connected to and employed for actuating one or more ordinary eccentrics
and their gearing for working a single or double slide valve applied to cylinders
with single or double ported seat and slide chest disposed in the middle of the
cylinder, or in like manner to apply this mode of giving motion to any other of
the well known arrangements ordinarily employed, and the novel arrangement
for giving motion to slide valves may thus be used alone, yet I prefer to
employ it in conjunction with an arrangement of ports, valves, seats and slide
chests which I have designed for the purpose, and by the use of which
economy is effected in the quantity of steam or other power employed. With
this object I construct each cylinder with two small slide chests, one at the
top and the other at the bottom of the cylinder, and I make the steam
ports short and opening direct into the top and the bottom of the cylinder,
the eduction or exhaust port being in each case below each steam port;
the two slide valve rods in this case are not connected together, but are worked
respectively and in proper time by means of two oval or eccentric wheels,
driven or rotated by one or more oval or eccentric wheels fitted upon the main
or crank shaft, which said driven wheels respectively give motion to 'an ordinary
eccentric arrangement for actuating directly or through the intervention of a
weigh shaft and spanner the slide valve, spindles, and slide.
Instead, however, of adopting a single steam port, each at the top and
bottom of the cylinder as just described, I may apply that part of my said
Invention which relates to the production of a pausing or alternately slow and
quick motion by means of oval or eccentric wheels, as described, to the working
of gridiron and other forms of valves.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Elder in the Great Seal Patent Office on the
14th April 1860.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
ELDER, of Glasgow, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifteenth day of October, in the year of our
Lord One thousand eight hundred and fifty-nine, in the twenty-third year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said John Elder, Her special licence that I, the said John
Elder, my executors, administrators, and assigns, or such others as I,
the said John Elder, 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 "IM-
PROVEMENTS IN STEAM AND OTHER ENGINES," upon the condition (amongst others)
that I, the said John Elder, my executors or administrators, 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 John Elder, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement and accompanying Drawings
This Invention relates to a novel mode of arranging and working the valve
gear and valves of steam and other engines, by which the alternate admission
and escape. of steam, air, &c., is regulated; and it consists in substituting for
the ordinary modes or methods in use for actuating the eccentric and valve
gear an arrangement as herein-after described in conjunction with either a
single or double port face or seat and slide valve chest, a novel arrangement
of wheel gearing for producing the desired motion of the slides.
Instead of placing the eccentric or eccentrics upon the crank shaft or main
shaft of the engine, and communicating the motion of the eccentric by means
of a rod connected to the eccentric strap at one end, whilst the. other end is
either connected direct to the slide valve rod, or to the spanner or lever of a
weigh shaft, which in turn communicates the requisite alternate action or motion

page_text: to the slide valve, and instead also of placing the eccentrics upon independent
shafts driven uniformly and at the same speed as the crank shaft or main shaft,
such motion being communicated to such eccentrics by means of spur gearing,
and instead also of the various contrivances for actuating slide valves by means
of cams of divers shapes, tappets, and such like mechanical means, I effect any
desirable amount of pause, slowing or cessation of motion in the travel of the
slide valves by the employment of oval or other eccentric wheel gearing for
giving motion to the slide valve or valves, the major and minor axes of these
oval wheels, or the amount of the eccentricity of the other eccentric wheels
being suitably proportioned to impart the requisite amount of action or motion
to the slide valves at the proper times, by the continuous and uniform rotation
of the main or crank shaft upon which the oval, volute, or other eccentrically
mounted driving wheel is fixed, whilst the corresponding wheel or wheels into
which it takes, and which it drives or rotates, is fitted upon the shaft carrying
the ordinary arrangements connected with the slide valve movement.
Now although I propose to apply one or more oval or other eccentric toothed
wheels as drivers for working a single or double slide valve applied to cylinders
with single or double ported seat and slide chest disposed in the middle of the
cylinder, or in like manner to apply this mode of giving motion to any other
of the well known arrangements ordinarily employed, and a novel arrangement
for giving motion to slide valves may thus be used alone, yet I prefer to employ
it in conjunction with an arrangement of ports, valve seats, and slide chests,
which I have designed for the purpose, and by the use of which economy
is effected in the quantity of steam or other power employed; and by it
the steam may be cut off at a very small proportion of the stroke, and
the exhaust port is kept open nearly the entire period of the stroke. With
this latter object I construct each cylinder. with two small slide chests, one at
the top and the other at the bottom of the cylinder, and I make the steam
ports short, and opening direct into the top and the bottom of the cylinder, the
eduction or exhaust port being in each case below each steam port. The two
slide valve rods in this case are not connected together, but are worked
respectively and in proper time, by means of two oval or other eccentric wheels,
driven or rotated by one or more oval or other eccentric wheels fitted upon the
main or crank shaft, which said driven wheels respectively give motion to an
ordinary eccentric stud-wheel or half crank arrangement for actuating directly
or through the intervention of a weigh shaft and spanner the slide valvė,
spindles, and slide.
Instead, however, of adopting a single steam port, each at the top and bottom
of the cylinder, as just described, I may apply that part of my said Invention

page_text: which relates to the production of a pausing or alternately slow and quick
motion, by means of oval or other eccentrically working wheels, as described,
to the working of gridiron slides and other forms of valves.
In the accompanying two Sheets of Drawings I have shown views of some
of the applications of my Invention to different kinds of steam engines, and
although I have not given any illustrations of its application to air or other
engines, the application thereto will be self-evident.
In Sheet 1, Figure 1 is a side elevation, partly in section, of an overhead beam
engine with a jacketted cylinder, the valves being set in motion by oval wheel
gearing, whilst two separate slide valves: regulate the admission to and escape
of steam from the cylinder, the one valve being at the top and the other at the
bottom of the cylinder; Figure 2 is a front elevation or end view of Figure 1,
looking toward the slide valve chests of the cylinder.
Figure 3 exhibits a part of an overhead beam land engine, fitted with oval
wheel gearing for actuating the slide valves, and combined therewith is shown
an arrangement of reversing gear, which may be applied to any other form
of engine.
In Sheet 2, Figure 1 is a longitudinal elevation, or a fore and aft view of a
pair of marine engines working diagonally. In this view an arrangement of
wheel gearing is shown generally, the same as at Figure 1, Sheet 1, but adapted
to the particular purpose for which they are there required. An arrangement
for reversing is also shown, adapted to the general construction of the engine,
and the position of the cylinders. In this view two sets of steam admission and
exhaust pipes are shown, and the lower valve chest is made to project beyond
the line of the upper valve chest, and each valve has a separate rod.
Figure 2 is a section of a steam jacketed cylinder, external views of which
are shown in Figure 1, having two separate slide valves, one at the top and the
other at the bottom, as before described.
Figure 3 is a modification of wheel gearing according to this Invention, for
giving motion to slide valves. In high-pressure engines, this valve gear
enables the valve-to work expansively without lap and cushioning in of the
steam.
In each of the several views, the respective parts, are so clearly defined, as
to render unnecessary literal references thereto, and the construction and mode
of applying and working the wheel gearing and the slide valves shown in the
several views, as also those applications which are not shown in the Drawings,
but are referred to herein, are so simple and readily understood by any one
conversant with the steam engine, as to render it unnecessary to describe them
at greater length, and although I have only shown a limited number of varia-

page_text: tions in the form and proportions and the mode of applying the toothed wheel
gearing for working the slide valves of steam and other engines, yet it will be
evident, that other proportions of the diameters one to the other of oval and
eccentrically working wheels and other relations of eccentricity may be given
to such wheel gearing, and other modifications and proportions of wheels than
those shewn at Figure 3, Sheet 2, may be substituted for acting upon or giving
motion to the slide valves of steam and other engines, such being in accordance
with the present Invention.
It will be seen on reference to the several views of the steam cylinders, that
by preference separate top and bottom ports and slide valves are shown con-
structed, arranged, and worked according to this Invention, but it will be
perfectly understood by all who are conversant with such matters, that the
wheel gearing shewn at Figures 1 and 3 of Sheet 1, and at Figures 1 and 3 of
Sheet 2, and any modifications thereof according to this Invention, may be
adapted to and employed for working the ordinary or any other description of
slide valve for engines worked by steam, air, or other power.
Having in the earlier part of this Final Specification described the nature of
my said Invention, and afterwards shewn and described some of the modes of
applying the same in practice which I prefer to employ, and in the two Sheets
of Drawings hereunto annexed, having illustrated some of the applications
referred to in the textual description, I wish it to be understood that I claim,
the arrangements and modes of employing and working wheel gearing for
actuating slide valves, as herein set forth; and I also claim the novel arrange-
ment and disposition of two separate sets of ports, slides, and slide chests to
each cylinder, as shewn and described herein, whether the slide valves thereof
be worked or operated by oval or other description of eccentrically working
toothed wheel gearing,
In witness whereof, I, the said John Elder have hereunto set my
hand and seal, this Thirteenth day of April, in the year of our Lord
One thousand eight hundred and sixty.
Witness,
RICHARD S. CUNLIFF.
JOHN ELDER. (L.S.)