IMPROVEMENTS IN CUT OFF VALVE GEAR FOR LOCOMOTIVE ENGINES, AND IN THE METHOD OF LUBRICATING THE SLIDE VALVES OF SUCH AND OTHER ENGINES AND RELIEVING A com- SAID VALVES OF PRESSURE
Year: 1882

page_text: LETTERS PATENT to Arthur William Lovell Reddie of the Office for Patents
66 Chancery Lane in the County of Middlesex, Patent Agent for an invention
of "IMPROVEMENTS IN CUT OFF VALVE GEAR FOR LOCOMOTIVE ENGINES,
AND IN THE METHOD OF LUBRICATING THE SLIDE VALVES OF SUCH AND
OTHER ENGINES AND RELIEVING
A com-
SAID VALVES OF PRESSURE
munication from abroad by John Swann of Montgomery in the State of
Alabama and Frank Richard Fennessy of the City and State of New York,
United States of America
"
PROVISIONAL SPECIFICATION left by the said Arthur William Lovell
Reddie at the Office of the Commissioners of Patents on the 7th March
1882.
ARTHUR WILLIAM LOVELL REDDIE of the Office for Patents 66 Chancery Lane
in the County of Middlesex, Patent Agent, IMPROVEMENTS IN CUT-OFF VALVE
GEAR FOR LOCOMOTIVE ENGINES, AND IN THE METHOD OF LUBRICATING THE
SLIDE VALVES OF SUCH AND OTHER ENGINES AND RELIEVING SAID VALVES OF
PRESSURE." [A communication from abroad by John Swann of Montgomery in the
State of Alabama and Frank Richard Fennessy of the City and State of New
York, United States of America.]
When a locomotive engine is fitted with any of the ordinary forms of link-
motion operating a main or distribution slide valve, the variation of the cut off of
said valve is effected by changing the relative positions of the link and link block.
This variation is limited however on account of the ensuing prejudicial distribution
inherent to the link motion operating a single valve when much linking up
is attempted
Notwithstanding this the link motion with a single valve is almost universally
applied to locomotives because of its simplicity. If, however, a separate cut-off
slide valve which did not entail the usual complexity of mechanism could be
applied to a locomotive, the advantages would be great, and such is the object of
the present invention.

page_text: To this end one feature of this invention consists in the combination with the
main or distribution slide-valve of an engine and an ordinary link motton for
varying the movement thereof, of a cut-off slide valve, consisting of a single plate
driven by suitable connections from the piston rod or cross head of the engine, so
that it has an invariable travel instead of a variable travel like ordinary cut-off
slide valves, and an invariable motion relatively to the piston, moving backward
and forward in unison therewith. Such a combination is advantageous, because
by it can be secured both an earlier and a greater variation of cut-off, with better
distribution, than is possible when a link motion operating a single slide valve is
used alone, as is common.
Another feature of this invention is applicable to slide valves of locomotive and
other engines (whether actuated by steam, compressed air or gas) in which the
valves are held to their seats by the pressure of steam or other motive agent upon
their backs, and has for its object to more effectively lubricate such valves and
valve seats, and at the same time to relieve them of excessive pressure by
counteracting the greater part of the pressure exerted upon their backs by the
steam, or other motive agent.
This feature of my invention consists essentially in the method of lubricating a
slide valve and relieving it of pressure by exposing the face of the valve to the
action of lubricating material under a suitable pressure relatively to the pressure
exerted upon the back of the valve, whereby a greater or less proportion of the
'pressure on the back may be counterbalanced.
The invention also consists in the combination with a valve seat, and a slide
valve having a cavity between them, of a reservoir or chamber in which lubricating
material is maintained under pressure, and a pipe or passage leading from said
reservoir or chamber to said cavity and serving to supply the lubricating material
to said cavity under pressure, whereby provision is afforded not only for effectively
lubricating the valve seat and valve, but also for relieving the valve of
*pressure.
The invention also consists in the combination with the above described cavity,
reservoir, and pipe or passage, of a stop-cock or valve in the latter, a throttle
valve controlling the admission of steam or other motive agent to the engine, and
connections between the first mentioned valve and the throttle valve, whereby the
former is closed slightly in advance of the latter, so that the valve will not be raised
from its seat when the pressure on its back is diminished by the closing of the
throttle valve.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Arthur William Lovell Reddie in the Great Seal Patent
Office on the 7th September 1882.
ARTHUR WILLIAM LOVELL REDDIE of the Office for Patents 66 Chancery Lane
in the County of Middlesex Patent Agent " IMPROVEMENTS IN CUT-OFF VALVE
GEAR FOR LOCOMOTIVE ENGINES AND IN THE METHOD OF LUBRICATING THE
SLIDE VALVES OF SUCH AND OTHER ENGINES, AND RELIEVING SAID VALVES OF
PRESSURE a communication from abroad by John Swann of Montgomery in the
State of Alabama and Frank Richard Fennessy of the City and State of New
York United States of America
"
When a locomotive engine is fitted with any of the ordinary forms of link-
motion operating a main or distribution slide valve, the variation of the cut-off
of said valve is effected by changing the relative positions of the link and link
block. This variation is limited however on account of the ensuing prejudicial
distribution inherent to the link motion operating a single valve when much
linking up is attempted. Notwithstanding this the link motion with a single
valve is almost universally applied to locomotives because of its simplicity. If
however a separate cut-off slide valve which did not entail the usual complexity
of mechanism could be applied to a locomotive, the advantages would be great
and such is the object of the present Invention.
To this end one feature of this Invention consists in the combination with the
main or distribution slide valve of an engine, and an ordinary link motion for
varying the movement thereof, of a cut-off slide valve, consisting of a single plate
driven by suitable connections from the piston rod or cross-head of the engine, so
that it has an invariable travel, instead of a variable travel like ordinary cut-off
slide valves, and an invariable motion relatively to the piston, moving backward
and forward in unison therewith. Such a combination is advantageous because
by it can be secured both an earlier and a greater variation of cut off with better
distribution than is possible when a link motion operating a single slide valve is
used alone as is common.
Another feature of this Invention is applicable to slide valves of locomotive and
other engines (whether actuated by steam, compressed air or gas) in which the
valves are held to their seats by the pressure of steam or other motive agent upon
their backs, and has for its object to more effectively lubricate such valves and
valve seats, and at the same time to relieve them of excessive pressure by
counteracting the greater part of the pressure exerted upon their backs by the
steam or other motive agent. This feature of the Invention consists essentially in
the method of lubricating a slide valve and relieving it of pressure by exposing
the face of the valve to the action of lubricating material under a suitable pressure
relatively to the pressure exerted upon the back of the valve, whereby a greater
or less proportion of the pressure on the back may be counterbalanced.
The Invention also consists in the combination with valve seat and a slide
valve having a cavity between them of a reservoir or chamber in which lubricating
material is maintained under pressure, and a pipe or passage leading from the said
reservoir or chamber to the said cavity and serving to supply the lubricating
material to the said cavity under pressure, whereby provision is afforded not only
for effectively lubricating the valve seat and valve, but also for relieving the valve
of pressure.
The Invention also consists in the combination with the above described cavity,
reservoir and pipe or passage, of a stop-cock or valve in the latter, a throttle

page_text: valve controlling the admission of steam or other motive agent to the engine, and
connections between the first mentioned valve and the throttle valve, whereby
the former is closed slightly in advance of the latter, so that the valve will not be
raised from its seat when the pressure on its back is diminished by the closing of
the throttle valve.
In the accompanying drawing Fig: 1 represents a partly sectional side view of
such parts of a locomotive engine as are necessary to illustrate the Invention;
including a side view of the reservoir for lubricating material, and a throttle valve
for the engine; Fig: 2 represents a longitudinal section of a portion of the cylinder
and the valve chests and valves upon a different plane from that on which the
section of the cylinder in Figure 1 is taken; Fig 3: represents a plan of the valve
seat and cylinder with the valve chest cover removed, and Fig: 4 represents a plan
of the valve face.
Similar letters of reference designate corresponding parts in all the Figures.
A designates the cylinder, and B a guide bar or slide; C designates the piston
which is connected to the cross-head D in the usual way.
A' designates the valve chest and E. the main or distribution slide valve, the
rod E. of which is operated by the arm E2 of the rock shaft in the usual way.
Es designates the arm of the rock shaft which carries the link F. which is
operated in the usual way by excentrics F¹. F. upon the crank shaft G.-
H designates the ordinary reversing lever for operating the link, and which
serves to vary the point of cut off as hereinafter described.
The valve seat has in it the usual induction and eduction ports, a, to which
steam or other motive agent is admitted by ports b. in the main valve, E, and c.
designates the exhaust port.
Upon the back of the main or distribution valve is a cut off valve I consisting
of a single plate, and which therefore is of fixed length. I¹. designates the cut off
valve stem which is connected to an arın in the rock shaft I and I³ designates a
second arm depending from said shaft and connected with the cross-head D by a
link I¹.
Hence it will be seen that the cut off valve I has an invariable travel and moves
backward and forward with the piston thereby having an invariable motion
relatively thereto.
It will be readily understood that the cut off valve is capable of no adjustment
while in operation, and the main or distribution valve E is set to cut off earlier or
later in the stroke by shifting the reversing or link operating lever H more or less,
and a greater variation of cut off with better distribution is thereby obtained than
can be obtained with the link motion alone.
In order that the engine may start at all points of the revolution the latest cut
off must be at least later than half-stroke, and this is insured when the cut off
valve clearance is taken greater than the main valve lap.
It will be evident that if the cut off valve were constructed to cut off upon its
outer edges instead of its inner edges it should travel reversely to instead of with
the piston and hence the valve rod I¹. should be connected above the rock shaft I'
instead of below it.
By driving the cut off valve in this combination by a connection with the piston
rod or cross head of the engine the movements of the said valve are made to corre-
spond exactly with the movements of the piston in both directions, whereas when
the cut off-valve is driven by an excentric, the said valve, owing to the changing
angles of the connecting rod of the excentric, does not exactly correspond with the
movements of the piston in both directions.
Referring now more particularly to Figures 2. 3. and 4, it will be seen that the
ports a. in the valve seat are not continuous across, but are intercepted by a bar or
bridge d. while the ports b. in the main or distribution valve E are intercepted by
a corresponding bar or bridge e. as also is the exhaust cavity or cove f-In the bar
or bridge, d. in the valve seat is formed a cavity g. of such dimensions that it will

page_text: always be covered by the bar or bridge e. of the valve.-From the cavity g. a
passage g leads to the exterior of the valve chest A', and there communicates with
a pipe g, which leads to a reservoir or chamber J for lubricating material, such as
oil. The reservoir or chamber J is provided with a glass gauge h. for indicating
the level of its contents and the passage of lubricating material from it through
the pipe g is controlled by a cock or valve i. Where one reservoir is used for two
cylinders, as in a locomotive the valve; i. may be a three-way cock with pipes
leading to both cylinders.
It will be readily understood that if a pressure be maintained upon the
lubricating material in the reservoir or chamber J. the same will be forced through
the pipe g². when the valve i is opened, and caused to fill the cavity g, so that it
will exert a pressure on the face of the valve which will tend to counteract that
upon its back. Inasmuch however as the area of the cavity g. must necessarily be
small relatively to the area of pressure on the back of the valve, the lubricating
liquid must be maintained under a much greater pressure than that of the steam
or other. motive agent, such a pressure may be maintained by means of an air pump
which may be connected to the pipe j, or by any other suitable apparatus.-It is
preferred to arrange the reservoir or chamber J. in the cab of the engine.
It will be seen that the valve seat will be effectively lubricated by the oil or
other material in the cavity g, and any which may escape therefrom will pass into
the cylinder and lubricate the piston.
K designates the throttle valve and K¹. the pipe through which steam or other
motive agent is conducted to the valve chest A¹.
The throttle valve K is operated by a handle k, and this handle is connected
with the handle l. upon the plug of the valve i by a link or rod . The two
valves when thus connected will be operated simultaneously, and these connections
are arranged so that the valve i will be closed just before the closing of the throttle
valve K.
By this means the pressure of liquid upon the valve face is wholly or nearly
taken off before the pressure of the steam or other motive agent on the back of the
valve is diminished, and hence there is no liability of the valve being thrown
from its seat by the pressure on its face being in excess of that upon its
back.
Having thus described the nature of the said Invention as communicated to me
by my foreign Correspondents and having explained in what manner the same may
be carried into practical effect I wish it to be understood that I claim :-
First In an engine the combination with a main or distribution slide valve,
and an ordinary link motion for varying the movement thereof, of a cut off slide
valve consisting of a single plate driven by a connection with the piston rod or
cross-head of the engine, so that it has an invariable travel and an invariable
motion relatively to the piston, substantially as and for the purpose herein
described.
Secondly. The method of lubricating the slide valve and relieving it of pressure
consisting in exposing the face of the valve to the action of lubricating material
under a suitable pressure relatively to the pressure of steam or other motive agent
exerted upon the back of the valve, substantially as and for the purpose herein
described.
Thirdly: The combination with a valve and valve seat having a cavity between
them, of a reservoir or chamber in which lubricating material is maintained under
pressure, and a pipe or passage leading from said reservoir or chamber to said
cavity, and serving to supply the material to said cavity under pressure, substantially
as and for the purpose herein described.
Fourthly: The combination with a valve and valve seat having a cavity between
them, of a reservoir or chamber in which lubricating material is maintained under
pressure, a pipe or passage leading from said reservoir or chamber to said cavity
and provided with a valve and a throttle valve for supplying steam or other motive

page_text: agent to the engine and so connected with the first mentioned valve that the latter
will be closed in advance of the throttle valve, substantially as and for the purpose
herein described.
In witness whereof I the said Arthur William Lovell Reddie have hereunto
set my hand and seal the seventh day of September in the year of our
Lord one thousand eight hundred and eighty two.
ARTHUR W. L. REDDIE.
(L.S.)