Improvements in or connected with Gear for Operating Cut-off or Expansion Valves of Engines Worked by Steam or other Expansible Fluid.
Year: 1894

page_text: Date of Application, 4th Sept., 1894
Complete Specification Left, 19th Oct., 1894-Accepted, 24th Nov., 1894
PROVISIONAL SPECIFICATION.
Improvements in or connected with Gear for Operating Cut-off or
Expansion Valves of Engines Worked by Steam or other
Expansible Fluid.
We, GEORGE THORNLEY and PETER THORNLEY both of Waterloo Engineering
Works, Burton on Trent, in the County of Stafford, Engineers, do hereby declare
the nature of this invention to be as follows:-
-
The object of this invention is to provide means whereby the cut off or expansion
valves of engines worked by steam or other expansible fluid can be operated with
great facility by the governor automatically or adjusted by hand to regulate as
required the degree of cut off. According to this invention the rod of the eccentric
by which the valve is operated is connected to the rod of the said valve by means of
a double armed lever the centre pin of which can be adjusted so as to vary the
amount of motion given to the valve by the said excentric. The adjustment of the
pin can be effected in any desired manner but it is preferred to connect it with
the governor in such manner that the cut off is automatically varied by the said
governor in accordance with the speed of the engine. The following is a convenient
arrangement according to this invention. The centre pin on which turns the lever
to the ends of which the rods of the eccentric and the valve are connected as
aforesaid, is mounted in a block which is movable by the governor the said pin being
provided with a piece which can slide in a slot in the said lever between the points
at which the eccentric rod and the valve rod are connected as aforesaid, so that the
stroke imparted to the valve by the excentric is varied by the governor moving
the said block carrying the said centre pin. To accommodate the movements of the
ends of the rods through arcs of circles the pin by which the excentric rod or the
valve rod is connected to the aforesaid lever may be extended and passed through
the end of a link or lever turning on a fixed centre.
Dated the 3rd day of September 1894.
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in or connected with Gear for Operating Cut-off or
Expansion Valves of Engines Worked by Steam or other
Expansible Fluid.
We, GEORGE THORNLEY and PETER THORNLEY both of Waterloo Engineering
Works, Burton on Trent, in the County of Stafford, Engineers do hereby declare
the nature of this invention and in what manner the same is to be performed
to be particularly described and ascertained in and by the following statement :-
The object of this invention is to provide means whereby the cut off or expansion
valves of engines worked by steam or other expansible fluid can be operated with
great facility by the governor automatically or adjusted by hand to regulate as
required the degree of cut-off. According to this invention the rod of the eccentric
by which the valve is operated is connected to the rod of the said valve by means
of a double armed lever the centre pin or fulcrum of which can be adjusted so as
to vary the amount of motion given to the valve by the said eccentric. The
adjustment of the pin can be effected in any desired manner but it is preferred to
connect it with the governor in such manner that the cut-off is automatically varied
D

page_text: by the said governor in accordance with the speed of the engine. The following
is a convenient arrangement according to this invention. The centre pin on which
turns the lever to the ends of which the rods of the eccentric and the valve are
connected as aforesaid is mounted in a block which is movable by the governor the
said pin being provided with a piece which can slide in a slot in the said lever
between the points at which the excentric rod and the valve rod are connected as
aforesaid, so that the stroke imparted to the valve by the excentric is varied by the
To accommodate the
governor moving the said block carrying the said centre pin.
movements of the ends of the rods through arcs of circles the pin by which
the excentric rod or the valve rod is connected to the aforesaid lever may be
extended and passed through the end of a link or lever turning on a fixed
centre.
In order that this invention may be clearly understood we will further describe the
same with reference to the accompanying drawings Figure 1 of which is a front
elevation, Figures 2 and 3 sectional elevations at right angles to each other
and Figure 4 a plan of apparatus constructed and arranged according to our
invention.
A is a standard carrying the governor B which is actuated by means of bevel
gear from a shaft C driven from the crank shaft or other suitable moving part of
the engine in the usual manner. D is a spindle which is moved longitudinally by
the governor and carries at its lower end a block E fitted to slide in guides F on
the standard A. Mounted so as to turn on a stud or pin G projecting from the
block E is another block H fitted to slide in a slotted bar I constituting a double
armed lever the fulcrum of which is the stud or pin G. To one arm of this lever
is attached at a the rod K of the eccentric by which the cut-off or expansion valve
is operated the other arm of the said lever being connected at 6 to the rod L of the
said valve. The slotted bar or double armed lever I is supported at its lower end
by a link M hung on a stud c from a plate or cap piece N fixed to the standard A
between which plate and the standard the blocks E and H slide. In the drawing
the block H is shewn in its lowest position in the slot of the lever I consequently
the fulcrum G of the lever is at its maximum distance from the end of the lever
where the valve rod L is attached in which position the said valve will receive from
the eccentric a full travel so long as the engine is running at a normal speed, should
however the speed of the engine increase the centrifugal action of the governor
will cause the block H to rise in the slot of the lever I whereby the fulcrum G of
the said lever will be moved nearer to the end and consequently reduce the travel
of the valve causing it to cut off and reduce the admission of steam to the cylinder
of the engine sooner than when the valve makes its full travel. The valve is thus
caused to cut off the steam sooner or later according as the fulcrum G is moved
by the governor nearer to or further froin the end 6 of the lever I the cut off being
thereby automatically regulated by the governor and the speed of the engine
maintained practically uniform.
If it be desired to adjust the travel of the valve by hand instead of automatically
by the governor the block H may be adjusted in position in the slot of the lever I
by any convenient means for example the rod or spindle D may be connected to
one end of a lever centered to the standard A so that by raising or lowering this
lever the block H may be moved into any desired position in the slot of the lever
according to the length of travel it is desired to give to the valve. Or the rod D
may be provided with a screw thread on which may be fitted a nut wheel bearing
on any suitable stationary part so that by turning this nut wheel in one direction or
the other the block will be raised or lowered in the slot of the lever and thereby
adjust the travel of the valve as desired.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed we declare that what we
claim is:
1. In connection with gear for operating cut-off or expansion valves of engines

page_text: worked by steam or other expansible fluid a double armed lever to which arms are
respectively connected the valve rod and the rod of the eccentric by which the valve
is operated the centre pin or fulcrum of the double armed lever being adjustable
on the lever so as to vary the extent of motion given to the valve by the eccentric
substantially as hereinbefore described.
2. In connection with gear for operating cut-off or expansion valve of an engine
worked by steam or other expansible fluid a double armed lever to the arms of
which the valve rod and the rod of the eccentric by which the valve is operated
are respectively connected, the centre pin or fulcrum of the double armed lever
being adjustable thereon and connected with the governor so that the cut-off is
automatically varied by the said governor in accordance with the speed of the engine
substantially as hereinbefore described.
3. The combination and arrangement of parts constituting means, whereby the
cut-off or expansion valves of engines worked by steam or other expansible fluid
can be operated by the governor substantially in the manner herein before described
and illustrated by the accompanying drawings.
2004
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, Agents.