IMPROVEMENTS IN " GOVERNOR AUTOMATIC CUT OFF VALVE GEAR FOR STEAM ENGINES follows:
Year: 1884

page_text: I, GEORGE LOW of Bishops Hill Cottage Ipswich in the County of Suffolk
Engineer do hereby declare the nature of my invention for IMPROVEMENTS IN
"
GOVERNOR AUTOMATIC CUT OFF VALVE GEAR FOR STEAM ENGINES
follows:-
"
to be as:
. I
This Invention has for its object improvements in the valve gear for automatic.
admission of a regulated quantity of steam to each end of the cylinder, according
to the variable load on the steam engine.
For this purpose I employ an ordinary slide valve with closed steam and exhaust.
ports on its front face for the secondary admission of steam to each end of the
cylinder, and for controlling the exhaust as usual; but it has a cylindrical bored
chamber lengthwise on the back of it. In this chamber are three or more ports-
also lengthwise communicating with the ordinary steam ports to which they are
at right angles. This chamber is fitted with a hollow circular turned cut off valve.
having the same number of ports and corresponding to those in the chamber. This
cut off valve has a to and fro circular motion imparted to it by means of which
the multiple ports are opened constant for the admission of steam to cylinder before,
the commencement of each stroke, and then closed against the steam earlier or
later in the stroke from about zero to about 625 or later according to the load on
the engine.
I impart the to and fro circular motion to the cut off valve by means of an arm
having a roller mounted at one end whilst the other end is fixed to the cut off
valve spindle. This roller runs between two circular cam plates mounted
horizontally on governor spindle of which the lower one which is in a constant
position has one or two inclined cams on it (one cam being used when governor is
arranged to run at twice the speed of the engine, and two cams when the same
runs at the same speed as the engine) which raises the aforesaid roller and arm
upwards through which the valve is turned in the direction for opening the
multiple cut off ports for the admission of steam before the commencement of each
stroke, whilst the upper one with corresponding cams, which is moveable by the
governor round its spindle lowers the roller and arm turning the valve in the
opposite direction to close the cut off ports cutting off the steam.

page_text: The governor operates upon the upper or moveable cam plate in the following
manner a sleeve turning upon the governor spindle is cast upon the upper side of
the said moveable cam, and has a spiral groove or grooves (or it may be a feather)
of a length equal to the total lift of the governor ring, and having a turn or pitch,
corresponding to the circular range of the cam or cams which limit is fixed
according to the range of cut off required which in the two cammed plate would
have a turn of about 625 or a little more in the half circle, and in the one cam
plate would have a turn of about 625 in the whole circle. A sliding die or dies
fixed inside the sliding ring of governor works in this spiral groove or grooves,
which as the governor balls and with them the ring rises or falls, turns the sleeve
and with it the moveable cam plate.
The times of cut off earlier or later on the stroke is regulated by the position of
the cam or cams on this moveable cam plate corresponding to the position of
the governor balls operating upon the same, thus when the balls are at the highest
position the cam or cams are in the position for pushing down the roller and arm
turning the valve for the earliest cut off at about zero or say 025 of the stroke,
and when the balls are in the lowest position the same cams are in position for the
latest cut off at 625 of the stroke or thereabouts, and any intermediate positions
of the balls give corresponding positions of the cam or cams for cutting off in the
aforesaid range.
The tendency of the sliding ring to turn with the thrust of the die on side of
spiral groove is prevented by having a reed fitted inside its upper end working in
a groove cut in governor spindle. In some cases however this may be dispensed
with by making the arms of governor sufficiently rigid and work in guides to take
the said thrust.
The governor is advantageously constructed so that the balls move in approximate
parabolic curves lifting a central weight or ring weighted till it balances the
centrifugal force of the balls when running at the average speed, as by this plan
the parabolic curve can be so designed, that the governor may be of any sensitive-
ness required so that the entire range of lift may be effected by 2, 3, 4 or more
revolutions per hundred revolutions of the engine.
Any other system of governor however can be applied to this plan of automatic
cut off gear by designing them so that they will act when running either at the
same speed as the engine or double that of the same.
During the time the roller with arm is free off the lifting and lowering cams
when passing from the one to the other, the circular cut off valve is held in the
proper position by the friction of the packing gland on its spindle, and by the
pressure of the steam, which may be assisted by an adjustable spring against
the back of the valve.
The cut off valve has no endwise movement the main valve therefore slides
over it on its strokes back and forward during part of which time the cut off valve
has a circular to and fro motion which thus equalises the wear of the valve faces.
Dated this 7th dow of Jul 1994
TONGUE & BIRKBECK,
34, Southamption Buildings,
Agents for the Applicant.

page_text: I, GEORGE LOW of Bishops Hill Cottage Ipswich in the County of Suffolk
Engineer do hereby declare the nature of my invention for "IMPROVEMENTS IN
GOVERNOR, AUTOMATIC CUT OFF VALVE GEAR FOR STEAM ENGINES" and in what
manner the same is to be performed to be particularly described and ascertained
in and by the following statement:-
This Invention has for its object improvements in the valve gear for automatic
admission of a regulated quantity of steam to each end of the cylinder, according
to the variable load on the steam engine.
For this purpose I employ an ordinary slide valve, with closed steam and exhaust
ports on its front face for the secondary admission of steam to each end of the
cylinder, and for controlling the exhaust as usual: but it has a cylindrical bored
chamber lengthwise on the back of it. In this chamber are three or more ports
also lengthwise communicating with the ordinary steam ports to which they are at
right angles. This chamber is fitted with a hollow circular turned cut off valve
having the same number of ports and corresponding to those in the chamber.
This cut off valve has a to and fro circular motion imparted to it by means of
which the multiple ports are opened constant for the admission of steam to
cylinder before the commencement of each stroke, and then closed against the
steam earlier or later in the stroke from about zero to about 625 or later according
to the load on the engine.
I impart the to and fro circular motion to the cut off valve by means of an arm
having a roller mounted at one end whilst the other end is fixed to the cut off
valve spindle. This roller runs between two circular cam plates mounted horizon-
tally on governor spindle of which the lower one which is in a constant position
bas one or two inclined cams on it (one cam being used when governor is arranged
to run at twice the speed of the engine, and two cams when the same runs at the
same speed as the engine) which raises the aforesaid roller and arm upwards
through which the valve is turned in the direction for opening the multiple cut off
ports for the admission of steam before the commencement of each stroke, whilst
the upper one with corresponding cams, which is movable by the governor round
its spindle lowers the roller and arm turning the valve in the opposite direction to
close the cut off ports cutting off the steam.
The governor operates upon the upper or moveable. cam plate in the following
manner a sleeve turning upon the governor spindle is cast upon the upper side of
the said movable cam and has a spiral groove or grooves (or it may be a feather)
of a length equal to the total lift of the governor ring, and having a turn or pitch,
corresponding to the circular range of the cam or cams which limit is fixed

page_text: according to the range of cut off required which in the two cammed plate would
have a turn of about 625 or a little more in the half circle and in the one cam
plate would have a turn of about 625 in the whole circle. A sliding die or dies
fixed inside the sliding ring of governor works in this spiral groove or grooves,
which as the governor balls and with them the ring rises or falls, turns the sleeve
and with it the movable cam plate.
The times of cut off earlier or later on the stroke is regulated by the position of
the cam or cams on this movable cam plate corresponding to the position of the
governor balls operating upon the same, thus when the balls are at the highest
position the cam or cams are in the position for pushing down the roller and arm
turning the valve for the earliest cut off at about zero or say '025 of the stroke and
when the balls are in the lowest position the same cams are in position for the
latest cut off at 625 of the stroke or thereabouts, and any intermediate positions of
the balls give corresponding positions of the cam or cams for cutting off in the
aforesaid range.
The tendency of the sliding ring to turn with the thrust of the die on side of
spiral groove is prevented by having a reed fitted inside its upper end working in
a groove cut in governor spindle. In some cases however this may be dispensed
with by making the arms of governor sufficiently rigid and work in guides to take
the said thrust.
The governor is advantageously constructed so that the balls move in approximate
parabolic curves lifting a central weight or ring weighted till it balances the centri-
fugal force of the balls when running at the average speed as by this plan the
parabolic curve can be so designed, that the governor may be of any sensitiveness
required so that the entire range of lift may be effected by 2, 3, 4 or more revolutions
per hundred revolutions of the engine.
Any other system of governor however can be applied to this plan of automatic
cut off gear by designing them so that they will act when running either at the
same speed as the engine or double that of the same.
During the time the roller with arm is free off the lifting and lowering cams
when passing from the one to the other the circular cut off valve is held in the
proper position by the friction of the packing gland on its spindle, and by the
pressure of the steam, which may be assisted by an adjustable spring against the
back of the valve.
The cut off valve has no endwise movement the main valve therefore slides over
it on its strokes back and forward during part of which time the cut off valve has
. a circular to and fro motion which thus equalises the wear of the valve faces.
And in order that my invention may be clearly understood I will proceed to
describe the same with reference to the drawings annexed which show several
views of governor automatic cut off valve gear or apparatus arranged and con-
structed so as to act in accordance with my invention.
Steam is admitted to each end of the cylinder a through an ordinary slide valve b
with closed steam ports c, c¹ and exhaust ports d in its front face access to the
steam ports being through other ports e, e, e, e, at right angles to them in the back
of the valve which is bored to receive a cylindrical valve flying with its axis
parallel to that of the steam cylinder a (Figures 1, 2 and 7 of the drawings).
This cylindrical valve which is open to the valve chest is provided with a set of
ports e¹, e, e³, et, corresponding with the ports e, e, e, e in the cavity in which it
works communicating with the ports c, c, in the face of the slide valve b. The
slide valve as a to and fro reciprocating motion in the usual way, and the
cylindrical valve f has an oscillating motion about its axis it has no endwise
motion.
The oscillating motion of the cylindrical valve f always admits steam to the slide
valve before the commencement of the stroke and then cuts it off again at some
point between zero and '625 according to the load on the engine. The admission

page_text: point is constant but the cut off is varied by the governor which acts on a rotating
cam g that operates the valve setting it backwards and forwards with relation to
the crank shaft h according to the requirements of the work. The motion of the
valve fis effected as follows.-
On the end of its spindle i is an arm k carrying a roller at its extremity. This
roller (Figures 1, 2 and 3) runs between two circular rotating cam plates g and g¹
on the governor spindle m (Figure 3) one of which effects the opening of the
valve and the other the closeure. Figure 11 is a development of these cams.
The former g¹ which is the lower of the two is fixed to the spindle m as its position
does not need to be varied but the latter g although obliged to rotate with the
spindle can be set backwards or forwards in relation to it within certain limits.
These limits depend partly upon the speed of the governor. If it make the same
number of revolutions as the crank shaft h the cams g. 9. must have two pro-
jections n, n, n¹, n¹, in it one for each stroke and its range of motion with relation
to the spindle will be about five eighths of half a revolution.
If the governor runs twice the speed of the engine the cams g, g¹ have one pro-
jection only and must be capable of moving twice the above amount. To operate
the movable upper cam g there is cast upon its upper side a sleeve o Figure 1
having in it a spiral groove p of a length equal to the lift of the governor ring and
a pitch corresponding to the desired motion of the cam g. A sliding dier in the
inside of the ring or sleeve 8 of the governor works in this spiral groove p and as
the arins t, t, rise and fall rotates the cam g one way or the other giving more or
less steam to the engine.
The cam plates g, g¹, are plain for the greater part of their circumference but
each has projections n n, n¹n which come in contact with the roller on the
arm k.
The fixed cam g¹ pushes it up to open the valve and leaves it there held by the
friction of the stuffing box u on the spindle i and by the pressure of the steam on
the back of valve f. The movable cam g then comes round and forces it down. If
the governor arms t t be extended to their widest range this occurs at the com-
mencement of the stroke while if they be closed it does not happen until five
eighths of the stroke have been accomplished. If the governor be constructed so
that the balls v, v, move in an approximately parabolic path and be made very
sensitive the speed of the engine can be kept constant within an extremely small
range.
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 I make
no claim to any of the parts separately which are well known and in common use
but what I claim is
First. The improved method of cutting off the steam by means of a cylindrical
valve (with cut off ports) oscillating on its axis and placed lengthwise in a bored
chamber in the back of an ordinary slide valve and having cut off ports corre-
sponding to those in the cylindrical valve communicating with steam ports in slide
valve all being arranged to act substantially in the manner and for the purpose
hereinbefore fully described and represented in the drawings hereto annexed.
I also claim the method of imparting the oscillating motion to the cylindrical
valve ƒ by means of the rotating cam plates g g¹ on governor spindle substantially
as described and shown.
Second. I claim the method of imparting the rocking motion to the cylindrical
valve f by the arm k and roller & on the spindle i of valve, being raised up or forced
down by the projections on the cam plates g and g¹ substantially as described and
shown in the drawings annexed.
Third. I claim the method of turning or setting the cam plate g for earlier or
later cut off by the governor actuating a die in a spiral groove on the sleeve
attached to the cam plate substantially as described and shown.

page_text: Lastly. I claim the improved general arrangement and combination of governor
automatic cut off valve gear or apparatus for governing and regulating steam
engines substantially in the manner herein before described and represented in the
drawings annexed.
TONGUE & BIRKBECK,
34, Southampton Buildings,
Chancery Lane, W.C.,
Agents for the Patentee.