Improvements in Apparatus for Governing or Regulating the Speed of Motive Power Engines.
Year: 1891

page_text: Date of Application, 20th Mar., 1891
Complete Specification Left, 19th Jan., 1892-Accepted, 20th Feb., 1892
PROVIDIUNAL DE DUIFICATION.
Improvements in Apparatus for Governing or Regulating the Speed
of Motive Power Engines.
We, FREDERICK CHARLES DUNAWAY, and FREDERICK WILLIAM DUNAWAY,
both of 183 Hornsey Road, in the County of Middlesex, Engineers, do hereby
declare the nature of this invention to be as follows:-
The invention has for its object improvements in apparatus for governing or
regulating the speed of motive power engines whereby the speed of the engine
can be practically uniformly maintained whilst running under varying loads or
pressures.
For this purpose we use any suitable arrangement of pendulum or other governor,
and we interpose between it and the throttle or other supply valve, an apparatus
which shall be operated by the governor to place a sliding bar connected with the
throttle or other supply valve, and consequently the latter, in position to maintain
the engine at the desired speed and to leave such sliding bar and supply valve in
such position until the speed of the engine is again varied, when by the temporary
increase of speed the governor will shift the said bar and valve so as to place the
latter in position to secure the desired regulation of speed.
The
For this purpose we connect the governor to a sliding rod carrying a pair of
pawls which are capable of acting to move a rack bar in one or the other direction
according to the direction in which the pawl bar is moved by the governor.
rack bar may be provided with a single rack with which both pawls are capable of
acting, the one in the one direction and the other in the contrary direction, to drive
the same, or such rack bar may be fitted with two racks, each of which is driven
by its own pawl, and each of such pawls is acted upon by a fixed cam or incline or
other suitable means, so that when one pawl is driving, the other is raised above
the teeth of the rack bar. Thus, on any variation in the load or pressure on the
engine taking place, the rotation of the governor will be momentarily accellerated
or retarded, whereby the rack bar, and consequently the supply valve, will be
moved in one or the other direction, until the normal or required speed is obtained,
and the valve will be left in such position until the load or pressure on the engine,
or the speed thercof from any cause, is again varied.
When the rack bar has arrived at its extreme position in the direction of opening
the supply valve, the driving pawl will be automatically lifted from the rack, thereby
preventing any injury to the apparatus.
The pawl bar, after having acted upon the rack bar, is capable of returning to
its central or normal position without giving motion to said rack bar.
As a modification the rack bar may be substituted by a toothed segment or
wheel, or by a pair of ratchet wheels or segments, in which case the pawls would
receive motion around the axis of such segments or wheels, and the fixed inclines,
cams, or other means for raising the pawls out of gear with the same would be
conveniently arranged for such purpose.
Dated this 20th day of March 1801
FRED. CHAS. DUNAWAY.
FRED. WM. DUNAWAY.
By Harris & Mills,
23, Southampton Buildings, London, W.C., Agents.

page_text: COMPLETE SPECIFICATION.
Improvements in Apparatus for Governing or Regulating the Speed
of Motive Power Engines.
We, FREDERICK CHARLES DUNAWAY, and FREDERICK WILLIAM DUNAWAY,
both of 183 Hornsey Road, in the County of Middlesex, Engineers, 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:
The invention has for its object improvements in apparatus for governing or
regulating the speed of motive power engines, whereby the speed of the engine
can be practically uniformly maintained whilst running under varying loads or
pressures.
5
For this purpose we use any suitable arrangement of pendulum or other governor, 1
and we interpose between it and the throttle or other supply valve, an apparatus
which shall be operated by the governor to place a sliding bar connected with the
throttle or other supply valve, and consequently the latter, in position to maintain
the engine at the desired speed, and to leave such sliding bar and supply valve in
such position until the speed of the engine is again varied, when, by the temporary 1
increase of speed, the governor will shift the said bar and valve so as to place the
latter in position to secure the desired regulation of speed.
For this purpose we connect the governor to a sliding rod carrying a pair of
pawls, which are capable of acting to move a rack bar in one or the other direction,
according to the direction in which the pawl bar is moved by the governor. The 2
rack bar may be provided with a single rack, with which both pawls are capable
of acting, the one in the one direction and the other in the contrary direction, to
drive the same, or such rack bar may be fitted with two racks, each of which is
driven by its own pawl, and each of such pawls is acted upon by a fixed cam or
incline or other suitable means, so that when one pawl is driving, the other is raised 2
above the teeth of the rack bar. Thus, on any variation in the load or pressure on
the engine taking place, the rotation of the governor will be momentarily accelle-
rated or retarded, whereby the rack bar, and consequently the supply valve, will
be moved in one or the other direction until the normal or required speed is
obtained, and the valve will be left in such position until the load or pressure on 3
the engine, or the speed thereof, from any cause, is again varied.
When the rack bar has arrived at its extreme position in the direction of opening
the supply valve, the rack for giving motion to it in that direction will be
automatically dropped from the pawl, thereby preventing any injury to the
apparatus.
The pawl bar, after having acted upon the rack bar, is capable of returning to
its central or normal position without giving motion to said rack bar.
3
As a modification the rack bar may be substituted by a toothed segment or
wheel, or by a pair of ratchet wheels or segments, in which case the pawls would
receive motion around the axis of such segments or wheels, and the fixed inclines, 4
cams, or other means for raising the pawls out of gear with the same, would be
conveniently arranged for such purpose.
And in order that our said invention may be more clearly understood and readily
carried into effect, we will proceed, aided by the accompanying drawings, more
fully to describe the same.
4

page_text: Figure 4 is a side view, and Figure 5 is a transverse section, of parts for
preventing injury to the apparatus, and Figure 6 is an end view, and Figure 7 is a
side view, of similar apparatus arranged to work in a circular direction instead of
longitudinally.
In all the figures like parts are indicated by similar letters of reference.
We will first describe the arrangement represented at Figures 1 to 5.
A represents the governor, B the valve, and the interposed apparatus giving
motion from the governor to the valve.
The governor shown at Figure 2 is of the kind known as the Pickering governor ;
it consists of three sets of flat or plate springs a fixed at their ends to discs or
frames a', a², and having threaded thereon, or fixed to each of them at the centre
of their length, a ball or weight, which, when a high rotary speed is given
to the governor, will fly out by centrifugal force and, by bending the springs a,
will cause the disc or frame to approach the disc or frame a¹ and thereby
give longitudinal motion to a central rod a fixed at one end to the disc or
frame a in such manner that the disc can revolve freely thereon. The rod a
also moves freely through a hollow spindle a fixed in the end of the frame c,
and forming an axle upon which the drum or pulley a², carrying the frame a¹
and attached governor, revolves.
The pulley is driven by a strap or band from the engine, thereby giving
rotary motion to the governor, and the central rod at has a stop a' fixed thereon to
limit its motion.
The valve B is of the kind known as an equilibrium valve; it consists of a valve
case bhaving an inlet orifice and an outlet orifice and channels or ways ³
bored in their walls to fit a pair of disc valves & fixed upon a rod passing
through a stuffing box at cach end of the valve case b. The governor A and
valve B above described are very suitable for use with our invention, but if desired
other descriptions of governor and valve may be employed. In order to regulate the
passage of steam through the valve as may be required to regulate the speed of the
engine, we cause the governor, through the rod at and interposed apparatus, to
shift the valves in the following manner.
The rod is connected to a sliding rod or bar c', which is mounted in guides or
cross frames fixed to the opposite sides of the frame c.
This rod or bar c¹ has
fixed to a projection on each side thereof, a stud or axis c³, on each of which a pair
of pawls c or are mounted; these pawls are arranged to work respectively with
racks c, c', fixed one on each side of the bar or rode, which is mounted in the
guides or cross frames c³, and is connected with the valve rod 6º.
c, co, are bars, which are connected respectively to the pawls e, , and rest on
the upper edges of the side bars of the frame c, each of which latter is formed with
a recess c or c¹. These recesses, in combination with the other parts of said side
bars, act as fixed cams so that when, in the motion of the bar c', the bars c', c₁ fall
from the more elevated parts of the side bars of the frame into the recesses ell, e¹²,
the pawls c or c are allowed to fall into gear with their rack c or '; the other
pawls cor care raised out of contact with their rack. The bars c, c10 also
extend over the bar c¹ and rest thereon when the pawls c', care in gear with their
racks.
C
If desired our improved apparatus represented at Figures 1, 2, 3, may be provided
with the safety apparatus represented at Figures 4 and 5, so that when the rack
bar has arrived at its extreme position in the direction for opening the valve, the
driving pawls and the rack will be separated from each other, thereby preventing
any injury to the apparatus.
This is effected in the following manner.
The rack c' is connected to the rack
bar e by links c¹³, one end of each of said links being pin jointed to the bar and
the other to the rack; one of these links has connected thereto, an arm c¹, thereby
forming a bell crank lever, and said arm has a pin at its outer end which runs in
the cam slot c¹ formed in one of the side bars of the frame c. By this means, when
the outer end of the arm c" arrives at the sunk portion of the slot c", it permits

page_text: the rack c' to fall away from the pawls c. We would here remark that in our
Provisional Specification we describe the raising of the pawl from its rack, but we
have found this impracticable, and have in consequence adopted the reverse
arrangement. This safety device however is not required if the parts are made
sufficiently strong.
We will now describe the arrangement represented at Figures 6 and 7. In
this case the valve B is an ordinary throttle valve provided with a disc ' fixed on
a shaft 6, which is used to more or less throttle the passage through the valve as
may be required. One end of this shaft is supported in a hearing in one side of
the valve case b, and said shaft passes through a stuffing box carried by the
opposite side of the case, and at its further end is supported in a bearing carried
by a standard 6. Mounted loosely on the shaft is a forked frame c', which is
connected, by a lever c* and connecting rod at, to any suitable governor.
To communicate rotary motion to the shaft, we mount on the frame c',
pawls ce, preferably in pairs and capable of gearing respectively with the
segmental racks c, c', formed or fixed on the wheel c, which latter is fixed on the
shaft between the two arms of the forked frame c¹. The pawls c, have
respectively fixed thereto bars c, co, which, when the said pawls are out of gear
with their respective racks, rest on the raised portions of the frames c and, when
the pawls are about to gear with their respective racks, the said bars c, c¹o fall off
said raised portions of the frames e and rest on the central segmental shaped portion
of the frame c¹, so as to regulate the depth to which the racks will fall and to.
prevent twisting strain thereon.
If required multiplying gear can be interposed between the lever e* and the
frame c, so as to enable the lever c, in moving through a comparatively small
arc, to communicate a more or less increased motion to the frame c and conse-
quently to the valve disc b'.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is
1. In apparatus for governing or regulating the speed of motive power engines,
the peculiar combinations and arrangements of apparatus, substantially as herein
shown and described with respect to Figures 1 to 5.
2. In apparatus for governing or regulating the speed of motive power engines,
the peculiar combination and arrangement of apparatus, substantially as herein
shown and described with respect to Figures 6 and 7.
3. In apparatus for governing or regulating the speed of motive power engines,
the interposition between the governor and the valve of a pawl bar or frame
attached to, and moved by, the governor, and a ratchet bar or wheel attached
respectively to the valve rod or valve shaft, substantially as herein shown and
described.
Dated this 19th day of January 1892
FRED. C. DUNAWAY.
FRED. W. DUNAWAY.
By Harris & Mills,
23, Southampton Buildings, London, W.C., Agents.