Improvements in the Valve Gear of Steam Engines.
Year: 1887

page_text: Date of Application, 11th Mar., 1887
Complete Left, 12th Dec., 1887
Complete Accepted, 10th Mar., 1888
Improvements in the Valve Gear of Steam Engines.
We, JOHN RICHARDSON of the City of Lincoln, Engineer, and BARTHOLOMEW
RICHMOND ROWLAND Engineer's Draughtsman of the same City do hereby declare
the nature of this invention to be as follows:-
This invention relates to improvements in valve gear for steam engines, whereby
"Corliss and trip-valve gear can be worked more effectively and economically than
previously, and also provides for automatically varying the point of cut-off.
The engine to which it is applied is built with Cornish double beat valves for the
admission and oscillating exhaust valves, and instead of being worked by eccentrics as
is usual, they are all worked by a shaft rotating at the same speed as the crank shaft
and at right angles with the same, parallel to the bed of the engine.
The admission valves are governed by eccentrics direct from this horizonial shaft
and so far the invention is common with many others of the same kind.
One improvement relates to the admission valves and consists of a release arrange-
ment; said valves being lifted by levers, the outer ends of which are depressed by
eccentric rods. The connecting rods carrying the upper ends of the eccentric rods
and also the bearings, describe an are so that as the bearings descend the eccentric
rods are pushed further from the centre of the lever until the said lever is released
which permits the valve to fall instantly into its seat.
We make the centre pin upon which the trip levers work moveable to the right and
to the left and their position is controlled by the governor spindle to which the centre
pin is attached. From this arrangement the centre of the trip lever when moved in
one direction causes the release to take place earlier, while if it is moved in the other
lirection it will be later.
We do not confine ourselves to the above described method but the special feature
of this part is automatically moving this centre to the right or to the left,

page_text: A further part of the invention consists in means for working the oscillating
exhaust valves from a shaft which is at right angles to the main valve gear shaft and
is carried on the same bracket, this shaft has two cranks forged within it, or two
eccentrics fitted upon it at suitable angles for working the exhaust valves.
The shaft could also serve as a convenient means for driving the governors.
CL 1SSZ
H. GARDNER,
166, Fleet Street, London,
Agent for the said J. Richardson
and B. R. Rowland.

page_text: We JOHN RICHARDSON, of the city of Lincoln, Engineer and BARTHOLOMEW
RICHMOND ROWLAND Engineer's Draughtsman, of the same city, do hereby declare
the nature of our said invention and in what manner the same is to be performed to
be particularly described and ascertained in and by the following statement:
This invention relates to improvements in valve gear for steam engines whereby
Corliss and trip valve gear can be worked more effectively and economically than
previously and also provides for automatically varying the point of cut off.
The invention will be understood by the annexed drawings.
The engine to which it is applied is built with Cornish double beat valves A, A, see
Figures 1.2 and 5 (for the admission) and with oscillating exhaust valves B. B,
see Figure and instead of being worked by eccentrics as is usual they are all worked
by a shaft. C rotating at the same speed as the crank shaft and at right angles with
the same parallel to the bed of the engine.
The admission valves A, A, are governed by eccentrics D, D, direct from this
horizontal shaft C and so far the invention is common with many others of the same
kind.
One improvement relates to the admission valves A, A, and consists of a release
arrangement, said valves being lifted by levers E, E, the outer ends F, F of which are
depressed by an appliance I connected to the excentric rods G.
The upper ends of the connecting rods G are carried by link rods H as are also the
irippers I, I, which describe an are so that as the irippers 1. partake of a descending
motion through the action of the excentrics D, they move further from the centre of
the lever E until they release themselves from the end F of the lever E which permits
the valves A, A, to fall instantly on to their seats.
According to one arrangement as at Figure 1, we make the centre pin J, excentric,
upon which the trip levers E, E, work, so that they, i.e. the levers can be moved ió
the right and to the left to determine the length of time that the valves A should be
held open, and their position is controlled by the governor spindle to which the centre
pin is attached. From this arrangement the excentric J. of the trip lever, when
moved in one direction, causes the release to take place earlier, while if it is in the
direction of the arrow it will be later.
Instead of the fulcrum being an excentric as at Figure 1, it may be a round rod,
as at Figures 2. and 3 and movable in the housings horizontally.
The fulcrum Jis coupled by small connecting rods M, M, to lever N by which a
horizontal motion is given to the fulerum in the housings by the varying positions of
the governor which operates the lever l', the iwo being connected at . By this
means the point of the tripping lever is caused to approach to and recede froin the
tripper and thus vary the point of cut off.
:

page_text: The lever P may have a cord or wire Q attached to it which may be carried all
round the mill or factory driven by the engine and in case of accident any person
pulling the cord can at once stop the engine and thus prevent further damage.
Figure 5 shows another modification of the trip gear.
In this case the valve lever E is cranked as shown at R and is acinated by a
tripper which is an arm at right angles to it. When working in the direction of
the arrow so as to open the valve the arin S of the tripper I comes in contact with the
rod I the position of which is adjustable by the governor L. Immediately the arm $
touches the rod T the tripper I is released and the valve A falls.
A further part of the invention shown at Figure 4 relates to means for working the
oscillating exhaust valves B, B, from a short shaft C which is at right angles to the
main valve gear shaft C and is carried by the same bracket W; this shaft C has two
cranks forged within it or two excentrics K, K, fitted upon it at suitable angles for
working the exhaust valves B, B. The shaft also serves as a convenient means for
driving the governors L, L, irough the rod 12.
Instead of fitting oscillating valves, as a Figure 4, we may fit triple ported slide
valves U, U, see Figures 2 and 3 worked at angles to the centre line of cylinder and
close underneath the same.
The working faces of the valves U, U, are those farthest removed from the cylinder
thus they are always pressed towards the face by the pressure of steam within the
cylinder and are never exposed to a greater pressure than this. Owing to their
relation with the valve driving shaft they are easily and simply worked. The
exhaust valves U, IJ, are so made that they can be easily examined or removed for
repairs by unfastening the covers V, V, without disturbing any other joints.
Having now particularly described and ascertained the nature of our said invention
and in what manner the same is to be performed we declare that what we claim is
1. The arrangement or mechanism for adjusting the cut off by altering the
horizontal position of the fulcrum J of valve lever E substantially as shown in the
drawings Figures 1. 2. 3 and 4.
2. The method of releasing the valves A A as described and as shown at Figure 5
of the annexed drawings.
3. The method of arranging the oscillatory exhausi valves B, B, and working same
from horizontal shaft as shown at Figure 1 of the drawings, also the modified
arrangement of exhaust valves shown at Figures 2 and 3 of the annexed drawings.
4. The connection of the lever P io the governor L at Lin the manner described,
also the means by which the engine can be instantly stopped.
The 10th day of December 1887.
H. GARDNER,
166, Fleet Street, London,
Agent for the said J. Richardson
and B. R. Rowland,