A NEW OR IMPROVED GOVERNOR FOR STEAM ENGINES
Year: 1874

page_text: LETTERS PATENT to Robert Rankin, of the City of Glasgow, in the
County of Lanark, North Britain, Engineer, for the Invention of
"A NEW OR IMPROVED GOVERNOR FOR STEAM ENGINES."
PROVISIONAL SPECIFICATION left by the said Robert Rankin at the
Office of the Commissioners of Patents, with his Petition, on the
1st April 1874.
I, ROBERT RANKIN, of the City of Glasgow, in the County of
Lanark, North Britain, Engineer, do hereby declare the nature of the
said Invention for "A NEW OR IMPROVED GOVERNOR FOR STEAM ENGINES," to
be as follows:-
This said Invention has reference to a new or improved construction
of governor, consisting substantially of a simple arrangement of three
main parts, namely, a reciprocating air pump, which, according to its
velocity and compression of air, actuates a valve so as to admit high-
pressure steam from the boiler or compressed. air from a close chamber,

page_text: either above or below a piston, reciprocating in a close ended cylinder,
so as to close or open the throttle valve of the engine, to which the
piston is attached by a rod working out through a stuffing box on one
end, and so regulate the speed of the engine; the whole consisting of a
most simple arrangement of reciprocating parts, having no revolving
balls or weights, and therefore more suitable, durable, and economical
for all kinds of high and low pressure steam engines, both for land and
marine purposes, than the governors heretofore in use. The piston of
the air pump, which is preferably solid; has its rod passed out through
the open end of its barrel or cylinder, or out through a stuffing box
when it has a close cover at both ends, so as to be reciprocated by any
motion taken from the engine to be governed by it, and preferably at
nearly the same speed, although it will act at a much faster or slower
speed. The acting end of the air cylinder (or both ends when these
are closed in and desired to compress the air and act) has a close cover,
and is fitted with an automatically acting valve, opening and admitting
air on the in-stroke of the piston, and closed by a light spring or weight
on the out-stroke of the piston, and having small slits or other holes for
the outlet of the air admitted, regulated by a closing ring or other lid to
suit the normal or ordinary speed of the plunger and engine. Thus an
extra pressure of air is caused in the close end of the cylinder, whenever
the piston runs away beyond its normal regulated speed (or, vice versa),
which immediately opens a small valve and admits the air into the
chamber below an equilibrium steam or air valve and chest (preferably
of the double piston slide valve class, so as to raise it and cut off and
exhaust the steam from the one end of the regulating steam (or it might
be air) cylinder and piston of the throttle valve, and admit it to tho
other end, so as to close or partially close the throttle valve, and thus
reduce or bring back the engine to or below its normal speed, when the
equilibrium valve will again fall, and admit the steam or air to the
opposite side of the regulating piston and open the throttle valve, by
the power of a light spring or weight on it, and a small escape spring
valve fitted to the chamber below the equilibrium valve, both of which
valves can be regulated by their springs or weights to the greatest
nicety in their action to suit the pressure of the air caused within the
close end of the air cylinder.
The regulating steam or air piston or its rod is preferabiv fitted witho
:

page_text: piston striking either end of the cylinder, or when preferred the cylinder
might be made to extend some distance beyond the inlet and outlet
ports, and so confine the steam and make it cushion the action of the
piston at the ends. When only one end of the air cylinder is made to
thus actuate the steam valve and govern the action of the regulating
piston and throttle valve, and it is preferred to use air instead of steam
to actuate this piston, the other end might be used as an ordinary air
pump for forcing air into an air receiver to any desired pressure,
regulated by a spring or weight loaded safety valve. To effect this the
air would be led from this receiver to the inlet pipe or duct of the
equilibrium or double piston valve (before described for admitting
the steam to the regulating cylinder), and so dispense with the use of
steam in this case; or a separate pump might be used for forcing the air
into the said chamber, when preferred, for so actuating the regulating
piston of the throttle valve.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Robert Rankin in the Great Seal Patent Office on
the 30th September 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT.
RANKIN, of the City of Glasgow, in the County of Lanark, North
Britain, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the First day of April, in the year of
our Lord One thousand eight hundred and seventy-four, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Robert Rankin, Her special licence that
I, the said Robert Rankin, my executors, administrators, and assigns,
or such others as I, the said Robert Rankin, my executors, adminis-
trators, and assigns, should at any time agree with, and no others,
from time to time, and at all times thereafter during the term therein
expressed, should and lawfully might make, usc, excrcise, and vend,
within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "A NEW OR IMPROVED GOVERNOR
FOR STEAM ENGINES," upon the condition (amongst others) that I, the said

page_text: Robert Rankin, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should
particularly describe and ascertain the nature of the said Invention, and
in what manner the same was to be performed, and cause the same to
be filed in the Great Seal Patent Office within six calendar months
next and immediately after the date of the said Letters Patent."
NOW KNOW YE, that I, the said Robert Rankin, do hereby declaro
the nature of my said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by
the following statement in writing, reference being had to the several
Figures on the accompanying two Sheets of Drawings, and to the
reference letters and figures marked thereon, that is to say :-
My said Invention has reference to and consists substantially of a new
or improved construction of governor for steam engines formed of a
compact and simple arrangement of three main parts, namely, a reci-
procating air pump A worked by the engine to be governed, and which
according to the velocity and compression of air it makes actuates a
controlling valve E (preferably a piston slide valve) so as to admit the
motive high-pressure steam from the boiler (or it might be compressed
air from a close chamber) on either side, or above or below the motive
piston reciprocating in a close ended cylinder I (being the third part),
the piston rod I of which works out through a stuffing box I, I³, on
one or both ends of the cylinder I, and is so connected by a connecting
rod J, and lever K, or other equivalent to the throttle or other inlet or
cut-off valve V of the engine as to regulate its speed, the whole con-
sisting of a most simple arrangement of reciprocating parts and valves
having no revolving wheels, balls, or weights, and therefore more
suitable, durable, and economical for all kinds of high and low pressure
steam engines both for land and marine purposes than the governors
heretofore in use, and particularly for the high speed compound engines
used for screw propulsion subject to rough weather when the power
required frequently varies...
:
I will now proceed to describe the several Figures and modifications
on the two Sheets of Drawings which I have hereunto appended for the
purpose of showing the full nature of my said Invention, and the best
modes and means I am at present aware of for performing or putting it
into effect or practice, the same reference letters indicating the same or
equivalent parts in all the Figures where shown.

page_text: Figures 1 and 1 A, Sheet 1, are vertical and horizontal sections all
complete, constructed in accordance with and illustrative of one modifi.
cation (or construction and arrangement of the parts) of my said Inven
tion or governor for steam engines placed and acting vertically.
Figures 2 and 3, on Sheet 2, are longitudinal and transverse vertical
sections; and Figure 4 is a plan corresponding to Figure 2, all respectively.
of a slightly different modification of my said Invention of new governor
from that shown on Sheet 1, in which however the moving parts aro
placed and arranged to work horizontally.
Figure 5 is a vertical section of a generally similar modification and
arrangement of the parts of this governor to that shown in Figures 2, 3,
and 4, but with the air pump A placed to be worked vertically from
below...
Figures 4A and 4 B arc respectively half plans of the actuating
steam cylinder I and piston I' of the governor showing two different
arrangements of ports k, k,&j, and valves 1, 2, for cushioning the piston I'
by the admission of live steam after the exhaust port i, ¿¹¹, or ¿¹, i³,
has
been shut, and before it reaches cither end of its stroke, the former
(Figure 4 A) corresponding to the mode shown in Figures 2 to 5 by
ports j, j, formed in the neck of the piston rod I², but the latter
(Figure 4 B) shows another mode of doing the same by admitting the
steam by a tappet valve in a port at each end of the cylinder I, and
which is opened by the piston striking its inner end before reaching the
ends of the cylinder.
Figure 6 shows a vertical section of an open speed (or fly) fan, such as
might be used and driven by the engine instead of the air pump A, for
regulating or governing the action of the steam or controlling piston
valve E of the governing steam cylinder I and piston I' attached to
the inlet valve V of the engine to be governed.
Referring, first, to the Figures 1, 1 A, on Sheet 1, the wholo;
governor or apparatus is preferably portable, and carried by the air-
pump A through the brackets or flanges A*, cast on it, and bolted to
any stationary part of the engine framing or side of the engine-house,
as at Z, or it might be carried and secured in any other convenient
manner or position. The piston A¹ of the air pump A in this case is.
shown solid, and is made to work fluid tight by ordinary metallic
packing rings A" sprung into grooves, but when made single acting it.

page_text: might have the inlet valve As fitted in it and packed with any other
metallic or ordinary hemp, or other clastic or flexible packing used for
air pumps, as shown in the modifications on Sheet 2. The actuating
piston rod A² in this instance is firmly fitted and screwed to the central
web at A of the piston A', and though shown broken away in the
Drawing, Figure 1, it is continued up out through the open end of the
barrel or cylinder A (or when this pump A is made double acting it
might work out through a stuffing box in one of the close ends) so as to
be reciprocated by any motion taken from the engine to be regulated by
this governor, and preferably at nearly the same speed; however, it will
act at a regular speed in relation to the engine although considerably
faster or slower than it. The lower or acting end a of the air cylinder
A. (when this is closed in and desired to act and compress the air, and
to give the initial acting power) has a close cover a¹ jointed on it. fitted
with an automatically acting valve A³, which opens to admit the air on
the in-stroke of the piston A', and closes by its own weight and pressure
of air within on the down or out stroke of this piston; or this might be
effected by a light spring or other equivalent when inverted or worked
horizontally, as in the Figures on Sheet 2. A closing or controlling
screw ring valve B and small slits B' (or it might be other equivalent
holes and valve) are fitted to this close end a¹ to regulate the inlet and
outlet of the air, and as a consequence its pressure within the pump, 'to
suit the normal or ordinary speed of the plunger A' and engine; so that
an extra pressure of air is caused in the close end a of the cylinder A
(whenever the piston A¹ and engine run away beyond their said normal
regulated speed, or vice versa) which immediately opens a small retention
valve C and admits the air into a chamber D, D', below or at one end of
a high pressure steam' (or it might be air) controlling valve E and its
chest E (preferably of the equilibrium or differential double piston slide
valve class) so as to raise it and cut off and exhaust the steam from the
one end of the regulating steam (or it might be high-pressed air)
cylinder I, and piston I', liaving its rod I connected to the throttle
valve V, and at the same time admit it to the other end so as to close or
partially close the throttle valve V, and thus cut off the steam from the
engine and reduce or bring it back to or below its normal speed, when.
the piston valve E will again fall (and admit the steam or high-pressure
air to the opposite side of the regulating piston I', and open the throttle
valve V again to the extent required to keep the engine at its normal
speed) by the re-action or power of the light differential regulating.

page_text: weights e on thic stem E3 of the valve E (or it might be a spring or other
equivalent, such as that of making the two acting ends or pistons of
the piston valve E slightly different in diameter) and a small screw
regulating escape balance. tap or valve F fitted to this chamber D, D',
below or between the piston valve E and check valve C (or it might also
be with an escape regulating screw tap or valve. G which nearly closes
by the action of the piston valve E at its extreme positions, as shown in
the modifications on Sheet 2), the opening or action of which valves is
preferred to be regulated by screw plugs, as shown at F' and G', and
fixed by hand jamb nuts F and 'G (but this might also be done by
weighted spring regulated valves), all to the greatest nicety in their
action, to suit the pressure of the air caused within the close end.
a of the air cylinder and that at the one end. D, D₁, of the valvo
chest E'.
.. Tlic regulating high-pressure steam (or air) piston I¹ or its rod I² is
preferably fitted with small buffer springs j inside the cylinder I (but
they might be. outside) to prevent the piston striking either end I
or I of the cylinder. I, or. wlien preferred, the cylinder might be made
to extend a sufficient distance as 3ths of an inch or so beyond the inlet
and outlet ports ¹¹ and after they have been closed by the piston
valvò E, to confine or admit live steam and make it cushion the action.
of the piston I at both ends, instead of by the springs j, j, or other
cushion. In this arrangement Figures 1 and 1A, the piston steam
valve E is made hollow, so that the acting steam from tho boiler which
is admitted by the branch E" enters it by the opening E¼ on one side,
and passes out through it by one or other of the two port e¹ or e² on the
opposite side and ends into the annular ports and leading to the
upper and lower ports " and i respectively of the motive regulating
cylinder I; while the exhaust of the. steam takes place from these ends
of the cylinder and ports through the central chamber f of the piston.
valve E, into the annular exhaust port f¹ out through the discharge
branch f". The ports E and e", e, on the opposite sides of the valve E.
are made of nearly the same area to balance the pressure and make it
nearly equilibric in its action. One end J' of the piston rod I² outside
one of its close ends and stuffing boxes I, I³, through which it works
has the lower end of the connecting rod J jointed to it at J', while the
other end J" is jointed to the lever K keyed on the spindle of the throttle.
valve V of the engine to be governed, so that the rising of the piston I'
:
:

page_text: closes the valve V, and the lowering of it to the position shown in
Figure 1 opens it nearly to its full extent; but it might be connected
in an equivalent manner to any other form or construction of valve for
controlling the inlet of the steam or acting fluid of motive engines, to
which other governers have heretofore been attached and used for
controlling their action.
In setting the governor to work with the parts fitted as shown on
Sheet 1, the operator controls the action of the piston valve E with his
one hand by its stem E³ above the weights e, to admit the steam through|
it, and the ports E, e, i, i", to the upper or lower end of the cylinder I
and piston I¹, to so raiso and lower the latter that it shall regulate or
govern the action of the throttle valve V and velocity of the engine to
its proper normal speed; and then with the other hand screw up the
valve B and shut the holes B', until the pressure of air at every down-
stroke of the air piston A¹ raises the check valve C and the piston
valve E to about half its stroke (the escape valve F being at this time a
very little open), so that the check valve C falls cach up-stroke of the
piston A' and then open open the escape valve Fa little more slowly until
the piston valve E also falls each up stroke of the piston A', and so that
it just seems to float lightly within half its lower stroke up and down,
cach down and up stroke of the air pump never quite cutting off the
steam from the port i, adding a small weight e to the top of the spindle E
if the valve E is too slow in falling to suit the stroke of the pump. The
said setting of the outlet air regulating balance, discharge valves being
done the governor will be self-acting; for the moment the engine and
pump A go too slow it will cease to lift the piston valve E, and leave the
steam entering and fully acting on the top end of the cylinder and
piston I, I³, and so keep the piston I¹ at its lowest position, and the
throttle valve full open as shown in this position in the Figure; and as
soon as the engine and pump A run away the least degree faster than
their normal speed, the pressure of air will be increased in the spaces a
and D, D¹, so as to raise and hold the piston valve E so high as to let the
steam in through the lower ports e², ", and i³, and act in the lower end;
of the cylinder I, and raise the piston I¹ so as to close the throttle
valve V, and so reduce the speed of the engine again to its normal
velocity or motion, acting much quicker than any other governor of
which I am aware; besides having the power of being set by the engine-
man in a few seconds to suit any normal speed of the engine desired for

page_text: the time being, thus making it especially suitable for the engines of sorew
ships which use the sails also, and engines which require thoir speed
to be advantageously varied.
The sharp and dotted blue arrows indicate the free inlet of the air,
b and its course and outlet respectively, in all the Figures where shown;
and the sharp and dotted red arrows indicate the inlet and course of the
high-pressure steam and its exhaust respectively in the positions of the
steam valve E and piston I in all the Figures as shown; while the sharp.
black arrows indicate the acting motion of the parts they are on and
0 their motion to open the throttle valve; and the dotted black arrows
indicate the reacting motion and that which closes the throttle valve of
the same parts. .
Referring to the modification of this my new governor, shown in
Figures 2 to 4, and 4A, on Sheet 2, and particular difference of con-
5 struction, and arrangement or disposition and action of the parts thereof
from that described in reference to Sheet 1, the three main parts A, I,
E, are made in separate castings or pieces, preferably of brass, all
bolted together by flanges and screws at 2, 2¹, over each other, with their
- axes in nearly the same longitudinal and transverse vertical plane as a
0 portable governor, all carried and secured by the broad flanges, and
screws at A on the lower side of the air pump A to any convenient,
part of the framing of the engine or its room, or it might be a bracket Z',
attached thereto for the purpose of forming a fixed or secure basement
or support for the whole, having the pistons A', I, I', and E, preferably
5 working horizontally, as shown (but it might be at an angle or vertically.
when more convenient), the rod A being reciprocated, as before stated,
by any crank, eccentric, or reciprocating or equivalent mechanical
motion of the engine, and all otherwise generally as before described in
reference to the equivalent parts in the Figures on Sheet 1, and as
0 indicated by the arrows on the like parts in these Figures 2, 3, and 4, on;
Sheet 2. The piston rod A² in this case has its inner end jointed at A™
to the air piston A', which is formed with an ordinary central circum-
ferential recess A" for the usual hemp or soft packing, and with the
inlet air valve A³ fitted in it with a closing spring or stop cover A. The
35 pressure regulating valves B, b, B', in this instance are made in the form
of a screw plug B and socket b, the former closing the small outlet
slits B' in the latter, which is screwed tightly into the close end cover a
of the air cylinder A, as also that of the chamber D of the check
1111

page_text: .
.
valve C, which chamber D is connected with the close end air
chamber D of the piston valve E and its chest E' by the pipe D".
This chamber D¹ has a close end D with long pin inside to stop the
piston valve E at its extreme stroke towards this chamber D, where, it
admits the steam to the ports i, ", and end I* of the cylinder. and
piston I, I, and which by its pressure keeps the throttle valve. V of tho
engine open, being connected to one end of the rod I², as described in
reference to the Figures on Sheet 1. In these Figures, 2 to 4, the piston
valve E is solid, with an annular central steam space E" between the
two pistons e and e', working fluid-tight and easy within the steam
chest E', the former e being. slightly larger than the latter e¹ to fully.
counterpoise the pressure of the steam on this, and the slight pressure of
the air on the end of the valve E, to bring it back against the pin D as
the air escapes from the chamber D, D', through the screw plug balance
valve F, F', fitted to it in the end cover D² and also out through the like
escape regulating valve G, G', fitted on the casing E¹ over the long solid
back end of the piston valve E, which has an annular port g in it
opposite the hole in the valve G, and a small hole g¹ through the end
and axis leading into the chamber D' opposite the end of the stop pin D³
which nearly shuts this hole when the end of the valve comes against
it; but when the valve E is driven (by the undue increase of the engine.
and pump A, A, and pressure of air within the chamber D, D',) quite
to the other end of its stroke to close the throttle valve, it shuts the
port g and outlet of air through the escape valve G, G¹, so as to give a
pause, and maintain the valve E there to give the steam time to press
the piston I' to the opposite end of the cylinder I, and close and
maintain the throttle valve V a sufficient time shut to restore the engine
to its normal speed,. when the regular speed of the air pump and
pressure of the air being restored, bring back the piston valve E to its
regular floating position near the chamber D', all otherwise substantially
as described in reference to the modifications and figures shown on
Sheet 1. In this case the exhaust takes place from the opposite
ends I, I, and ports 1, 2, of the governing or regulating steam
cylinder I, through the two annular recesses of formed in the piston
valve E, into the two passages f¹, f', and out through the discharge
branch f, each formed in and on the opposite side of the casing E' to
that of the inlet steam branch E". The stem E of the piston valve E
works out through the opposite close end of its casing E to that of the
air chamber D', and has a wood handle or knob-e on it for the attendant

page_text: to work it by one hand, so that the piston valve E and the actuating
-piston I, I, of the cylinder I control the throttle valve of the engine to
be governed, all as a small direct-acting engine for that purpose, and
by these improvements also worked automatically by the action of
the air pump and its regulating, check, and escape and balanco
valves B, b, C, G, and F.
Although the moving escape valve ports are shown to be full open
to the plug and hole G during the greater part of the traverse of
the piston valve E, and shut it at once, only at the extreme up
stroke, when it makes the steam cylinder or engine E, I, I', shut the
throttle valve, it is to be understood that the port might be made of
curved or other differential shape or construction as to gradually close it
during the stroke of the valve E to the said extreme position, and thus
give a longer pause at any given extreme position to give time for the
steam piston I' to act on the throttle valves, as before explained, before
the pressure. of air falls in the chamber D' and the valve comes away
back. The piston I¹ is cushioned at the ends of its stroke by live-steam
conveyed from the central steam space E of the piston valve case E!
by the port passing round the one side of the steam cylinder I to
the longitudinal port leading into the open bush rings at the
bottom of the end stuffing boxes I¹¹ and I³, so as to pass into cither end
of the cylinder I through the shallow recess. or port j¹, j', formed in the
neck of the piston rod I just before the piston approaches the close
cover I or I³ after the exhaust port. ¹¹ or respectively have been
closed by the valve E or the piston I, so as to cushion it and prevent its
knocking against the end of the cylinder I instead of the springs shown
on the arrangement on Sheet 1, and all as more particularly seen in
Figures 3 and 4 A, and as arranged in Figures 2, 4, and 5; also.
Referring to the half plan, Figure 4 B, instead of this arrangement of
hollow recess and bush in the end covers I¹¹ and I³, and ports j, j', in
this piston rod I² for admitting the cushioning steain at the end of the
cylinder I, a small valve chamber and tappet valve is fitted at the
side of each stuffing box in the end covers 1" and I³, and into which the
live steam port enters. Each valve is inserted through the screw
plug holes and its inner end projects some little distance within the
end of the cylinder so that the piston I strikes it in time to open the
valve and admit the steam and cushion the piston I¹ before it reaches
the end cover I or I³ of the cylinder I. A condensed water drawing

page_text: off tap m is fitted to the lowest part of the steam cylinder I, or it might
be other convenient part of the steam valve chest E and cylinder I
or a lower pocket or pipe connected to these to draw off any water
which might collect from the steam condensing in them, as shown in
Figure 3.
Referring to the modification of my said new or improved governor
shown in Figure 5, the construction and arrangement of the steam valve
and its chest E, E', and motive cylinder I and piston I' or engine for
controlling the throttle valve V of the engine to be governed, and other
air regulating, escape, and balance valves A³. G, g, and F are all sub-
stantially as described in. reference to and shown in Figures 2, 3, 4,
and 4 A; but the air pump A is here inverted and secured vertically by
its upper solid end a¹ to a broad flange I' on the lower middle part of
the cylinder I, and which have the air check valve and its scat. C, C¹,
and air chamber D respectively fitted and formed in them, the latter
being connected by the angle tube Du to the air chamber D' at the end
of the steam piston valve E and chest E'. The whole governor so fitted
is carried in this case by a broad circular flange A* cast all round the
upper part of the pump barrel. A secured by bolts to the flanged eye.
formed in the bracket Z' shown broken away but understood to be
secured to some fixed part of the framing of the engine or to the walls
of the engine room. The air piston A' is thus in this case worked by
the lower end of its piston rod A² from any convenient part of the
engine, and it is formed, packed, and fitted with the inlet air valve A³,
all otherwise as described in reference to and shown in the latter modifi-
fication and Figures 2 to 4, except that as. the valve works vertically it
shuts by its own weight without the use of the spring A' there used.
When only one end of the air cylinder A is made to thus actuate the
steam valve and govern the action of the regulating piston I' and throttle
valve and it is preferred to use air in the cylinder I instead of steam to
actuate the regulating or governing piston I', the other end of the air
pump A might be used as an ordinary air-forcing pump for forcing the
air into an air receiver to any desired pressure which could be regulated
by a spring or weight, loaded escape, or safety valve. . To effect the action
of the piston I¹ in the cylinder I (instead of the steam) the air would be
led from the receiver to the inlet duct pipe e¹ of the equilibrium or
double piston valve E (before described as for admitting the steam to
the regulating cylinder I), and so dispense with the use of steam in this

page_text: case, or otherwise a separate air pump may be used for forcing the air
into the said air pressure magazine or chamber, when preferred, for so
actuating the regulating piston 'I' of the throttle valve I.
I believe that pneumatic governors have heretofore been tried or used,
with but indifferent success, for governing the fluid inlet valves of steami
engines and other motors with an air-forcing pump and pressure regulating
escape valves, but with the air, so forced or pressed, used as the direct
motive power acting in an air cylinder to move its piston coupled by its
rod to the said valves. It will be seen however by the foregoing
description and accompanying Drawings that my said Invention or new
governor is quite different from these and does not make the air to do
this or act in the same way, but consists, substantially or mainly, rather
in the use of a separate and special small direct acting reciprocating
steam engine (or it might be high-pressure air or other motive fluid
engine although I do not prefer these) E, I, I', having its piston rod
coupled to the inlet valve of the engine to be governed, combined with
an air pump A, A¹, worked by the said engine used only for actuating
the slide valve E of the said small special governing engine having the
pressure and action of the pressed air controlled by a regulating check
and balance valve, all as a portable governor for steam engines. The
action of the slide valve E of the governing engine E, I, I', might be
so controlled by other forms or constructions of air-forcing pump or
apparatus than that A, A', hercin described and preferred, either attached
to and portable with it on the same frame, or carried and worked
adjacent to it by the engine to be governed; or otherwise, when desired,
although I do not prefer it, this valve E might be worked direct by the
action of a mechanical governor of the air fan reacting class such as
shown in Figures 6 and 6 A, on Sheet 2 (or other equivalent ordinary
governor), and not by the direct action and pressure of confined air, as
described in reference to and shown in all the other Figures 1 to 5 on
the said accompanying two Sheets of Drawings, and which I prefer to
this reacting fan arrangement.
Referring to the construction and action of this arrangement, as
shown in Figures 6 and 6A, one end of the spindle E² of the slide
valve E working out through the close end of its steam casing E' is
connected direct by a connecting rod or other equivalent to the end of
the rod R, shown as broken off in this Figure. The end R' of this rod,
shown in the Drawing, is connected by a ball-and-socket joint R¹, R",

page_text: revolving loosely on
stays, as shown in the
so that it can reciprocate without revolving with the three longitudinal
arms R² attached to this socket R", and to the neck and stems S¹ of
three of a set of four fan blades S attached to and revolving with their
cross eye or boss S" mounted loosely on so as to revolve with, and
slide laterally on their driving spindle T between the two stay brackets S³
.and Ss keyed or otherwise fixed on the same shaft, and secured to each
other by the two longitudinal stay bars S at such a distance apart, and
on each side of the neck of the stem S₁ of the fourth fan blade S (not
.connected by the links R") as to allow a roller S
the neck of the said fan blade S, S¹, between these
transverse section Figure 6 A, so that the stays S drive the whole set
of fans, and allow them at the same time to traverse as a rolling parallel
action by the roller S¹ more or less according to the velocity of the
spindle T and reaction of the air on the angled fan blades S, so as to
reciprocate the rod R to and fro longitudinally to actuate the steam slide
valve E of the governing engine E, I, I', of the throttle valve of the
engine to be governed. The spindle T of this reacting set of fans is so
carried in the duplex journal bracket T¹ bolted to any convenient part of
the framing of the engine to be governed as to be driven by a band
passing over the pulley U keyed on it, and over any pulley on the
motive-power engine shaft, or any shaft driven by it, and in the direction
indicated by the arrow, and at such a high normal speed in proportion
to the crank shaft, regulated to some extent by the angle the blades $
are or may be set and fixed by the pinching screws & in their sockets of
the boss S¹¹, that the reaction of the air on the fan blades S makes them
float or slide slightly on the spindle T close to the back end of their
lateral motion and bracket S and position shown in the Drawings when
the throttle valve V is open to suit the said normal speed of the engine;
all so that any undue or increased speed and reacting resistance of the
air on the blades S shift the rod R in the outward direction of the arrow
on it, and shut the throttle valve V of the engine to be governed, all by
the action of the steam on the piston I¹ of the governing steam
cylinder I, and vice versa; any lowering of the speed of the fans S and
decrease of the reacting resistance of the air on them would allow the
pressure of steam on the differential parts e, e¹, of the piston valve E to
force back the rod R and set of fans S in the direction of the dotted
arrow on the Figure to their normal working position again, so as to
open the throttle valve of the engine suitably to that speed, all other
wise substantially as herein-before described in reference to the other

page_text: Figures on the accompanying Sheet of Drawings. The backward
reciprocating action of the boss S¹ of the fans S to their normal working
position might when desired be assisted by a spring or other equivalent
in addition to or instead of the differential action of the steam on the
two different sized pistons c, c¹, on the steam or piston slide valve E.
Although a piston slide valve E only has been shown and described
for controlling the inlet and exhaust of the steam (or other motive fluid
used) to and from the motive cylinder I, considering this the best for
being actuated and controlled by the action and pressure of the air, yet
still it is to be understood that other forms of slide valves, or other con-
struction of valves may be adopted, especially when it is to be actuated"
by a mechanical motion or air re-acting fan, or other governor, as shown
at Figures 6 and GA.
Having thus particularly described the nature of my said Invention;
and the manner in which the same is or may be performed, I have
to state that I do not restrict myself to the precise details herein
described or delineated, but what I believe to be novel and original,
and therefore claim as the Invention secured to me by the herein-
before in part recited Letters Patent is,―
First. The construction and use of governors for steam engines, with
a small motive steam engine or cylinder, and piston (I, I¹) with its con-
trolling valve (E) actuated by an air pump and compressed air, con-
trolled by regulating check and escape or balance valves, all substan-
tially as herein described in reference to and shown in the accompanying
Drawings.
Second. The construction and use of governors for steam engines,
cach with a steam cylinder, the piston rod of which is connected to tho
throttle valve of the engine, and having the slide valve of the cylinder
actuated by an air pump worked by the engine, that is, the governor of
a steam engine formed with a steam cylinder and an air pump, the air
forced by the latter actuating the slide valve of the former, the piston
rod of which works the throttle valve of the engine to be governed, all
substantially as herein described in reference to and shown in the
accompanying Drawings.
Third. The construction and use in steam engine governors with a
steam and air cylinder, of an air space (D, D',) between the check valvo
(C) and piston or slide valve (E), fitted with an air balance or escape

page_text: valve (F; F¹,) and either with or without an escape valve and port
(G, G', g) for controlling the action of the valve (E) of the steam
cylinder, all substantially as herein described in reference to and shown
in the accompanying Drawings.
Fourth. The construction and use in steam engine governors with a
steam cylinder, of a hollow or solid piston slide valve (E) or its equi-
valent, balanced in its lateral action and pressure, but having one end
rather larger in diameter than the other to give it a slight extra pressure
and tendency to move in the direction of the large end, whether con-
trolled by an air pump or reacting air or other governor, all substantially.
as herein described in reference to and shown in the accompanying
Drawings.
Fifth. The construction and use in steam engine governors of a closc
ended double acting steam cylinder, with its piston cushioned, all sub-
stantially as herein described in reference to and shown in the accom-
panying Drawings.
In witness whereof, I, the said Robert Rankin, have hereunto set
my hand and scal, this Twenty-eighth day of September, in the
year of our Lord One thousand eight hundred and seventy-four.
Witness,
W. R. M. THOMSON,
Patent Agent, .
Glasgow.
ROBERT RANKIN. (L.S.)