IMPROVEMENTS IN APPLIANCES FOR CONTROLLING THE ADMISSION OF STEAM PROVISIONAL SPECIFICTIAON
Year: 1874

page_text: LETTERS PATENT to Edward Hulme, of Liverpool, in the County of
Lancaster, Engineer, and John Hulme and William Hulme, of
Bradford, in the County of York, Engineers, for the Invention of
"IMPROVEMENTS IN APPLIANCES FOR CONTROLLING THE ADMISSION OF STEAM
PROVISIONAL SPECIFICTIAON left by the said Edward Hulme, John
Hulme, and William Hulme at the Office of the Commissioners of
Patents, with their Petition, on the 25th February 1874.
We, EDWARD HULME, of Liverpool, in the County of Lancaster,
Engineer, and JOHN HULME and WILLIAM HULME, of Bradford, in the
County of York, Engineers, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN APPLIANCES FOR CONTROLLING THE ADMISSION
OF STEAM AND OTHER ELASTIC FLUIDS TO MOTIVE POWER ENGINES," to be as
follows:-
The main objects of our Invention are (a) to regulate the motion of
the slide valve in such manner that an equal quantity of steam or other

page_text: 1
clastic fluid shall be admitted to each end of the cylinder; (b) to arrange
the governor to operate the expansion valve in such manner that the
speed of the engine shall be practically uniform.
In engines as at present constructed, where the slide valve eccentric
is scoured on the crank shaft the said valve has a greater speed of
motion at one end of the stroke, and a less speed of motion at the other
than the piston. Tho said want of harmony of the piston and valve
motions arises from transmission of motion from the piston through the
crank and connecting rod to the crank shaft and slide valve.
It will be obvious that in engines where a high degree of expansion
of steam or other clastic fluid is employed it is objectionable to allow
the valve to be open for a longer period at one end of the stroke than at
the other.
Now as means for ensuring the admission of equal quantities of steam
to cach end of the cylinder I place the eccentric which works the slide
valve on a countershaft driven from the crank shaft by eliptical or
eccentric.gearing. The cliptical or eccentric gearing gives the counter-
shaft, and with it the eccentric, a relative increase of speed of revolution
when the crank pin is at the opposite side of its centre of revolution to
the centre of oscillation of the connecting rod, and decrease of speed when
the crank pin is in the opposite position. The eliptical or eccentric
gearing is so adjusted that the eccentric on the countershaft shall give
a motion to the slide valve practically in harmony with the motion of
the piston.
As means for controlling the expansion valve through the governor I
make use of a train of four wheels, the first secured to the crank shaft,
the second attached to a radius rod on the crank shaft, gearing with the
former; the third attached to a radius rod on a countershaft, gearing
with the second; and a fourth secured on a countershaft, gearing with
the third. The second and third wheels on the radius rods are connected
together by a link. The expansion eccentric is secured on the counter-
shaft, or as we prefer, is connected thereto by cliptical or eccentric
gearing, as described for the slide valve eccentric.
It will be obvious that if the two connected radius wheels aro
stationary, as regards their centres of motion, the expansion valve will
cut off steam at a set point of the stroke. To cause the valve to cut off
steam at an earlier or later portion of the stroke all that is necessary is

page_text: to cause the second and third wheels, by means of their connecting
links, to partly rotate round the first and fourth wheels.
To cause steam to be automatically cut off at varying lengths of
stroke, according to the work being done, I cause the governor to move
the second and third wheels through their connecting link. I prefer
that the governor should be entirely detached from the said connecting
link, and should give motion to it in one or other direction by means of
screw friction or other gearing when the governor is revolving above or
below its normal speed.
The gear allows of the cut-off being regulated by hand, and of the
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Edward Hulme, John Hulme, and William Hulmo
in the Great Seal Patent Office on the 25th August 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, EDWARD
IIULME, of Liverpool, in the County of Lancaster, Engineer, and JOHN
HULME and WILLIAM HULME, of Bradford, in the County of York,
Engineers, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-fifth day of February, in the
year of our Lord One thousand eight hundred and seventy-four, in the
thirty-seventh year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto us, the said Edward Hulme, John
Hulme, and William Hulme, Her special licence that I, the said
Edward Hulme, John Hulme, and William Hulme, our executors,
administrators, and assigns, or such others as we, the said Edward
Hulme, John Hulme, and William Hulme, our executors, admini-
strators, and assigns, should at 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 APPLIANCES
FOR CONTROLLING THE ADMISSION OF STEAM AND OTHER ELASTIC FLUIDS TO MOTIVE-

page_text: POWER ENGINES," upon the condition (amongst others) that we, the said
Edward Hulme, John Hulme, and William Hulme, our executors or
administrators, by an instrument in writing under our, or their, or one
of their hands and scals, should particularly describe and ascertain
the nature of the said Invention, and in what manner the same was to be 5
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 we, the said Edward Hulme, John Hulme,
and William Hulme, do hereby declare the nature of our said Invention, 1
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 Sheet of illustrative Drawings, and to
the figures and letters marked thercon, that is to say:―
The main objects of our Invention are (a) to regulate the motion of 1
the slide valve in such manner that an equal quantity of steam or other
clastic fluid shall be admitted to cach end of the cylinder; (b) to arrange
the governor to operate the expansion valve in such manner that the
speed of the engine shall be practically uniform.
In engines, as at present constructed, where the slide valve eccentric 2
is secured on the crank shaft the said valve has a greater speed of
motion at one end of the stroke and a less speed of motion at the other
than the piston. The said want of harmony of the piston and valve
motions arises from transmission of motion from the piston through the
crank and connecting rod to the crank shaft and slide valve.
It will be obvious that in engines where a high degree of expansion
of steam or other clastic fluid is employed it is objectionable to allow
the valve to be open for a longer period at one end of the stroke than at
the other.
Now as means for ensuring the admission of equal quantities of steam
to each end of the cylinder we place the eccentric which works the slide
valve on a countershaft driven from the crank shaft by elliptical or
eccentric gearing. The elliptical or eccentric gearing gives the counter-
shaft, and with it the excentric, a relative increase of speed of revolution
when the crank pin is at the opposite side of its centre of revolution to
the centre of oscillation of the connecting rod, and decrease of speed
when the crank pin is in the opposite position. The elliptical or eccentric

page_text: gearing is so adjusted that the eccentric on the countershaft shall give a
motion to the slide valve practically in harmony with the motion of the
piston.
As means for controlling the expansion valve through the governor we
make use of a train of four wheels, the first secured to the crank shaft,
the second attached to a radius rod on the crank shaft, gearing with the
former; the third attached to a radius rod on a countershaft, gearing
with the second; and a fourth secured on the countershaft, gearing with
thic third. The second and third wheels on the radius rods are connected
together by a link. The expansion eccentric is secured on the counter-
shaft, or as we prefer, is connected thereto by elliptical or cccentric
gearing, as described for the slide valve eccentric.
It will be obvious that if tho two connected radius wheels arc
stationary, as regards their centres of motion, the expansion valve will
cut off steam at a set point of the stroke. To cause the valve to cut off
steam at an earlier or later portion of the stroke all that is necessary is
to cause the second and third wheels by means of their connecting links
to partly rotate round the first and fourth wheels.
. To cause steam to be automatically cut off at varying lengths of
stroke, according to the work being done, we cause the governor to
move the second and third wheels through their connecting link. Wo
prefer that the governor should be entirely detached from tho said
connecting link, and should give motion to it in one or other direction
by means of screw friction or other gearing when the governor is
revolving above or below its normal speed.
The gear allows of the cut-off being regulated by hand, and of the
engine being reversed by ordinary link motion when two eccentrics are
Fig. 1 is a plan, and Fig. 2 a side elevation of expansion and slide
valve gear, constructed and arranged in accordance with our Invention.
The first part is illustrated by the parts a, b, c, d, and e. a, counter-
shaft, on which is secured the slide valve cccentric b. The countershaft a
is driven from the first motion shaft c by the eccentric wheels a, e. It
will be obvious that if the eccentric wheels d, e, are properly arranged
the motion of the slide valve will be in harmony with the motion of the

page_text: piston. Instead of the eccentric gearing shown elliptical gearing might
be used.
The second part is illustrated by the train of wheels f, g, h, i. The
first wheel is secured to the countershaft a; the second g is attached
to the radius rod j, and gears with f; the third is attached to the
radius rod k and gears with 9; and the fourth i is secured on the
countershaft and gears with h. To the countershaft is secured the
expansion valve eccentric. The second and third wheels g, h, are con-
nected by the link or piece m which retains the ends of the rods j, k, in
position.
It will be obvious that end motion in the picco m will cause the
wheels g, h, to move around the wheels f, i. At the same time the
wheels g, h, will turn on their own axes and alter the relative position
of the wheels fand i, thus changing the position of the eccentric n, and
with it the expansion valve. The position of the picco m is changed by
the revolution of the shaft o operated through the friction wheels p, q, ".
The friction wheels p, r, are thrown into gear with the wheel q when
the governor rotates above or below its normal velocity.
Fig. 3 is a plan, and Fig. 4 a side clevation, of a modification
of apparatus constructed under our Invention. Here 1 is the main
shaft; 2, countershaft; 3, 4, eccentric wheels; 5, slide valve eccentric.
As means for altering the expansion valve the four bevel wheels 6, 7,
8, and 9, with the collar wheel 10 and endless screw 11 are used instead
of the arrangement illustrated under Figs. 1 and 2. The wheel 6 is
secured to the shaft 2, the wheel 7 to the eccentric 12 by the sleeve 13.
The wheels 8 and 9 gear with the wheels 6 and 7 and are secured to the
collar wheel 10.
It will be obvious that as the scrow 11 is caused to rotate by the
governor or by hand the collar wheel 10 will revolve, carrying with it
the wheels 8 and 9, which by their rotation around the shaft 2, and at
the same time on their own axes, will alter the relative position of tho
wheels 6 and 7, thus causing the cut-off to come into carlier or later
operation.
Having now described the nature of the said Invention, and par-
ticularized the same in such manner that others will be enabled to carry
our Invention into practice, we claim :—
First. The eccentric or elliptical gearing arranged substantially as

page_text: EDWARD HULME. (L.S.)
In the presence of