A New or Improved Valve Gear suitable for Pumps, Water Motors, Steam Engines, and the like.
Year: 1891

page_text: Date of Application, 11th May, 1891
Complete Specification Left, 11th Feb., 1892-Accepted, 12th Mar., 1892
PROVISIONAL SPECIFICATION.
A New or Improved Valve Gear suitable for Pumps, Water Motors,
Steam Engines, and the like.
I CHARLES HENRY NAYLOR of Moorland Cottage, Drighlington in the
County of York Draughtsman do hereby declare the nature of this invention to be
as follows:-
My invention refers to means for actuating the distributing valve of water,
steam and other motors, directly from the reciprocating motion of the piston rod;
and may in some cases be applied to actuate a cut-off valve working in conjunction
with a distributing valve.
My invention in its simplest form comprises a rocking shaft, whose axis lies
directly above (or below) the mid position of the piston rod crosshead, supposing
the stroke of the latter to be horizontal. On this rocking shaft is mounted a crank,
the pin of which passes through a bearing formed in and towards one end of a
lever; the opposite end of said lever being provided with a fork or suitable slot
bearing, which fits over the pins of the cross-head. The rocking shaft end of the
lever is connected to the distributing valve, whilst the pin of the rocking shaft
crank is connected to a spring or to the piston rod of a piston, which by means of
water or other pressure is pressed or pushed in one direction only; that is so as to
move the crank towards the mid stroke position of the crosshead, or into a position
vertically under the axis of the rocking shaft. For the sake of distinction the piston
just above mentioned is hereinafter referred to as the valve gear piston.
As the crosshead approaches either end of its stroke, the above mentioned lever
and the crank come gradually into line with each other. Immediately this occurs,
which is just as the cross-head completes its stroke, the pressure of the afore-
mentioned spring or of the valve gear piston suddenly draws the crank pin down
into the vertical position; thereby advancing the end of the lever connected to the
distributing valve, and consequently the distributing valve, so as to start the main
piston on the next half stroke.
As the main piston or crosshead moves from the end of its stroke, the cross-head
pins catching against the upper end of the fork or slot bearing of the lever, push
forward and raise the latter, and with it the rocking shaft crank, until a little past
mid stroke; when the lever begins to incline in the opposite direction, gradually
pulling down the crank, so that the crank and the lever gradually come into line
with each other just as the main piston completes the half stroke. The afore-
mentioned spring or valve gear piston then suddenly draws the crank pin down
into the vertical position, advancing the end of the lever connected to the distri-
buting valve and consequently the distributing valve, so as to again reverse the
motion of the main piston.
Modifications in the construction and working of this valve gear may be
made.
a). By making the distance from the distributing valve lever joint to the crank
centre in the lever greater than the length of the rocking shaft crank. This
arrangement is equivalent to adding lap or giving lead to the valve.
6). The lever instead of sliding over the cross-head pins may be arranged to
slide over pins connecting the free end of a swinging link with a connecting link
from the crosshead. The rocking shaft is then centred vertically above the mid
position or mid-swing of such pins, and the swinging link is centred vertically
above the rocking shaft. This arrangement necessitates a shorter extension of the
spring or a shorter stroke of the valve gear piston for moving the rocking shaft
crank.

page_text: Or in this modification the swinging shaft may be centred below the rocking
shaft.
c). By a suitable arrangement of valves or a cataract connected with the valve
gear cylinder, the motion given to the distributing valve from the end of the lever
may be varied, so as to control the speed of the main piston, as for example to
cause a pause at each end of the stroke.
d). By altering the length of the lever, the stroke of the main piston may be
varied.
e). By causing the valve to be brought automatically to the centre of its travel,
whenever the engine exceeds a speed, variable at the will of the attendant. This
may be done in several ways as for example by raising the axis of the rocking
shaft, on carrying forward the lower end of the lever in advance of the crosshead.
Dated this 9th day of May 1891.
J. CLARK JEFFERSON,
2, East Parade, Leeds, Agent for Applicant.
COMPLETE SPECIFICATION.
A New or Improved Valve Gear suitable for Pumps, Water Motors,
Steam Engines, and the like.
I CHARLES HENRY NAYLOR of Moorland Cottage Drighlington in the
County of York Draughtsman 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:-
My invention refers to means for actuating the distributing valve of water, steam,
and other motors, directly from the reciprocating motion of the piston rod; and
may in some cases be applied to actuate a cut-off valve working in conjunction
with a distributing valve.
My invention in its simplest form comprises a rocking shaft, whose axis lies
directly above (or below) the mid-position of the piston rod crosshead, supposing
the stroke of the latter to be horizontal. On this rocking shaft is mounted a crank,
the pin of which passes through a bearing formed in and towards one end of a
lever; the opposite end of said lever being provided with a fork or suitable slot
bearing, which fits over the pins of the crosshead. The rocking shaft end of the
lever is connected to the distributing valve, whilst the pin of the rocking shaft
crank is connected to a spring or to the piston rod of a piston, which by means of
water or other pressure is pressed or pushed in one direction only, that is, so as to
move the crank towards the midstroke position of the crosshead, or into a position
vertically under the axis of the rocking shaft. For the sake of distinction, the
piston just above mentioned is hereinafter referred to as the valve gear piston.
As the crosshead approaches either end of its stroke, the above mentioned lever
and the crank come gradually into line with each other. Immediately this occurs,
which is just as the crosshead completes its stroke, the pressure of the afore-
mentioned spring, or of the valve gear piston, suddenly draws the crank pin down
into the vertical position; thereby advancing the end of the lever connected to the
distributing valve, and consequently the distributing valve so as to start the main
piston on the next half stroke.
As the main piston or crosshead moves from the end of its stroke, the crossbead
pins catching against the upper end of the fork or slot bearing of the lever, push
forward and raise the latter and with it the rocking shaft crank, until a little past
midstroke, when the lever begins to incline in the opposite direction, so that the
crank and lever gradually come into line with each other, just as the main piston
completes the half stroke. The aforementioned spring or valve gear piston, then
suddenly draws the crank down, advancing the end of the lever connected to the
distributing valve, and consequently the distributing valve so as to again reverse
the motion of the main piston.

page_text: Modifications in the construction and working of this valve gear may be
made :-
a). By making the distance from the distributing valve lever joint to the crank
centre in the lever greater than the length of the rocking shaft crank. This
arrangement is equivalent to adding lap or giving lead to the valve.
b). The lever instead of sliding over the crosshead pins, may be arranged to
slide over pins connecting the free ends of a swinging link with a connecting link
from the crosshead. The rocking shaft is then centred vertically above the mid
position or mid swing of such pins, and the swinging link is centred vertically above
the rocking shaft. This arrangement necessitates a shorter extension of the
spring or a shorter stroke of the valve gear piston for moving the rocking shaft
crank.
Or in this modification the swinging shaft may be centred below the rocking
shaft.
c). By a suitable arrangement of valves or a cataract connected with the valve
gear cylinder, the motion given to the distributing valve from the end of the lever
may be varied so as to control the speed of the main piston, or rather the No. of
strokes per minute; as for example to cause a longer or shorter pause at each end
of the stroke.
d). By altering the length of the lever, the stroke of the main piston may be
varied.
e). By causing the valve to be brought automatically to the centre of its travel,
whenever the engine exceeds a speed, variable at the will of the attendant. This
may be done in several ways, as for example by raising the axis of the rocking
shaft, or carrying forward the lower end of the lever in advance of the crosshead.
And in order that my invention and the manner in which the same is to be
performed may be more clearly understood I have annexed hereto the accompanying
sheet of drawings.
In this-
Figs. 1 and 2 are respectively side elevation and plan of a pump or water motor
constructed according to the modification referred to above under heading .
Figs. 3, 4 and 5 are diagrammatic views illustrating the action of my valve gear
as applied to steam or expansive fluid motors.
In all the figures the same letter refers to the same or corresponding part.
a is the rocking shaft placed vertically above the mid position of the pin bat
the free end of the swinging link c. The free end of this swinging link c is con-
nected to the main piston crosshead d by means of the connecting rod e.
C
fis the rocking shaft crank. In these figs. the rocking shaft a is shewn provided
with two cranks ƒ and', instead of one as above described. The pin of the
former (i.e. f) passes through a bearing formed in the lever and near the upper
end of the same. This upper end is connected by means of the connecting rod h
and lever i, with the distributing valve of the pump or motor (shewn in section in
Figs. 3, 4 and 5, and there indicated by the letter (). The lower end of the
lever is provided as shewn in Fig. 1 with a fork or slot bearing, in which
the pin can slide.
b
m is the above mentioned valve gear piston, connected to
the rocking shaft crank, and which (m) serves to bring back the rocking shaft
crank into the vertical position, immediately the crank and lever
line, and thereby operates the distributing valve as above described.
g come into
When constructed as above described without modification, the rocking shaft a is
placed vertically above (or below) the mid position of the piston crosshead d, the
swinging link c is dispensed with, and the fork or slot bearing at the lower end of
the lever g fits over a pin attached to the crosshead.
When the valve gear piston m pushes down the rocking crank f, the slot or fork
at the end of the lever g allows the necessary amount of play for the pin b, or more
strictly allows the lever g to be pulled away momentarily until the motion of the
main piston again brings them into contact.
The modification under the heading a is obtained by making the distance on the

page_text: lever 9, marked 1,-2 in Figs. 1, 3, 4 and 5, greater than the length of the rocking
shaft crank f. This arrangement is equivalent to adding lap or giving lead to the
valve.
The modification under heading c is illustrated in Figs. 2 and 3, the valve gear
piston cylinder or cataract cylinder being shewn in black section. In Fig. 2 the
water or other fluid finds its way back into the cylinder along or through passages
formed in the seat of the valve or in the valve itself. In Fig. 3 which refers to
the valve gear as employed for steam motors, two valves or rather openings are
shewn, the one covered by a ball valve, the other by an adjustable screw by means
of which the rate of the inflow of the water or other fluid can be regulated; so
that if desired, the duration of the pause may be made greater than the time taken
by the motion of the main piston for one half stroke. In other words, the inflow of
water may be made to occupy more time than is required by the main piston to
move from one end of the cylinder to the other.
The modification under heading d is effected by altering the length of the
lever g. Thus if the length of the lever g be shortened, the crank f and the lever g
come into line sooner, and operate the distributing valve sooner, stopping the stroke
earlier ;
i.e. shortening the stroke; whilst if the length of the lever g be increased,
the stroke of the main piston is increased.
P
The distributing valve may be brought automatically to the centre of its
travel whenever the engine exceeds a certain speed, as referred to under heading e,
in the manner illustrated by Figs. 3, 4, and 5; which as above observed refer to
steam motors. A. spring n is inserted between the pin b and the inner end of the
fork or slot bearing of the lever g, or as shewn in Figs. 3, 4 and 5 between an
adjustable collar and the block 3. When the motion of the main piston is not
too rapid, the valve gear piston m is driven in, forcing the water or other fluid
through the valves at the back of the cylinder. If the motion of the motion of
the main piston however becomes so rapid, that it tends to move the valve gear
piston more rapidly than the escape of the water a fluid behind the same can take
place, then the spring n is compressed, and the lever g is less inclined, causing the
distributing valve to be brought automatically towards the centre of its travel,
thereby throttling the steam earlier in the stroke, as shewn in Fig. 5. When the
motion of the main piston is not too fast, as just before described, the cut-off does
not take place till near the end of the stroke, as shewn in Fig. 4.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is:-
1° A valve gear in which the distributing valve is operated by a spring or valve
gear piston actuating a rocking crank, when such crank is brought into line with a
lever hinged about the crank pin by the motion of the main piston.
2° The improved valve gear consisting of the rocking crank, mounted vertically
above (or below) the mid position of the crosshead d or of the swinging link c;
the pin of the rocking crank fitting in bearings near one end of the lever g; the
lever g with a bearing near one end for the pin of the rocking crank f, and con-
nected from this same end to the distributing valve, and with a slot bearing at the
opposite end for the crosshead or swinging link pin b; and a spring or a valve gear
piston tending to bring the rocking crank back to its mid position; all substantially
as herein set forth and also as illustrated.
3° The respective modifications under the headings a, b, c, d and e substantially
as herein set forth or as illustrated.
4° The improved valve gear substantially as herein set forth or as illustrated in
the accompanying drawings.
Dated this 10th day of February 1892.
J. CLARK JEFFERSON,
2, East Parade, Leeds, Agent for Applicant.