IMPROVEMENTS IN GOVERNING OR REGULATING APPARATUS APPLICABLE TO TRAMWAY AND OTHER ROAD LOCOMOTIVE ENGINES
Year: 1881

page_text: LETTERS PATENT to Thomas Hunt, of Fairfield, near Manchester, in the
County of Lancaster, Engineer, for an Invention of "IMPROVEMENTS IN
GOVERNING OR REGULATING APPARATUS APPLICABLE TO TRAMWAY AND
OTHER ROAD LOCOMOTIVE ENGINES."
PROVISIONAL SPECIFICATION left by the said Thomas Hunt at the Office
of the Commissioners of Patents on the 10th November 1881.
THOMAS HUNT, of Fairfield, near Manchester, in the County of Lancaster,
Engineer. "IMPROVEMENTS IN GOVERNING OR REGULATING APPARATUS APPLICABLE
TO TRAMWAY AND OTHER ROAD LOCOMOTIVE ENGINES,"
In carrying out my Invention I apply to a tramway or road locomotive engine,
independently of the driving wheels of the engine, an axle upon which is a wheel
or two wheels with or without flanges, which wheel or wheels rolling upon the
rail or rails, or roadway, give a revolving motion to the axle, which axle by toothed
or other gearing is connected to a governor, such as is used on a steam engine, the
balls of which expanding as the speed increases, actuates a finger which indicates
the speed at which the engine and its load is travelling, and the governor, which
may be of any suitable type, being also connected by levers and rods or any other
convenient arrangement to a valve situated between the steam regulator and the
cylinders, shuts off the steam to the cylinders when the speed of the engine exceeds
the limit fixed upon by the authorities, and at the same time the governor, being
also connected by means of levers and rods or any other suitable method to a valve
which turns the steam on to the steam brake, opens that valve and applies the
steam brake
The rolling wheel or wheels by their revolving motion may also be made to
register the distance travelled by the engine.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Thomas Hunt in the Great Seal Patent Office on the 10th May
1882.
THOMAS HUNT, of Fairfield, near Manchester, in the County of Lancaster,
Engineer. "IMPROVEMENTS IN GOVERNING OR REGULATING APPARATUS APPLICABLE
TO TRAMWAY AND OTHER ROAD LOCOMOTIVE ENGINES."
My Invention consists in applying to tramway and other road locomotives,
independently of the driving wheels of the engine, an axle upon which is a wheel,
or upon which are wheels with or without flanges, which wheel or wheels, by
rolling upon the rail or rails, or roadway, give a revolving motion to the axle, on
which axle a governor may be fixed; or if more convenient, the axle may be
connected by toothed or other gearing to a governor, which governor may be like
that commonly used on a steam engine, the balls of which, expanding as the speed
increases, actuate a finger which indicates the speed at which the engine and its
load are travelling, and the governor being also connected by levers and rods, or
any other convenient arrangement, to a valve situated between the steam generator
and the cylinders, shuts off the steam to-the-cylinders-when-the-speed-of-the-engine-
exceeds the limit fixed upon by the authorities, and at the same time the governor,
being also connected with the inlet for steam to the steam brake, opens the valve
and applies the brake.
And in order that my said Invention may be fully understood, I shall now
proceed more particularly to describe the same, and for that purpose shall refer to
the several Figures on the annexed Sheet of Drawings, the same letters of reference
indicating corresponding parts in all the Figures.
Figure 1 represents in side elevation, and Figure 2 in end elevation, so much of
a locomotive as is necessary to illustrate the application of my Invention thereto;
A, A, are the ordinary running and driving wheels of the locomotive. To the
framing of the locomotive is attached a bracket B by guides, upon which it is
capable of sliding vertically. The said bracket carries in a bearing at its lower end
the shaft C of a wheel C, which runs upon the rail or road, and is independent of
the ordinary wheels A. The said shaft C has keyed thereon a bevel pinion C³,
which gears with another bevel pinion d upon a spindle D, the upper part which
slides vertically within the governor spindle E (which is carried by the bracket B³),
and is caused to rotate with it by means of a key or similar attachment. The
spaces at e are for the allowance of this vertical movement, the object of which is
to enable the wheel C₁ to rise and fall upon the guides with any inequalities of
the road or roads, and to allow the said wheel to be raised out of action if
desired. If necessary the adhesion of the wheel C on the rail or road may be
increased by placing upon it, through a spring, as at x, a portion of the weight of
the engine.
The rod F slides in the upper part of this governor spindle E, cotters g
passing between collars on the said rod, the said cotters having connected to them
the connecting links g' of the governor balls, the arms to which the said balls are
attached being centerd to lugs h carried by the hollow upper part of the governor
spindle E, the said hollow upper part of the spindle having long slots d² therein
for the passage and upward travel of the cotters g with the rod F, which rod has
a rack fat its upper end engaging with a toothed wheel i upon an axis ², carrying
the indicating finger of a speed indicating dial I. The rod F has a collar at fi for
bringing the steain valve to its normal position, as hereinafter explained, and also
a collar at f, which may be adjustable upon a screw thread formed on the said
rod. To a fulcrum J carried by the body of the engine or other support is affixed a
double bell crank or three arm lever 1, 3, 3, one arm j having a fork embracing

page_text: the rod F, another arm carrying a weight, and the third arm being connected
by a rod with the hollow piston, steam valve K sliding in the valve casing L,
into which at M open the steam inlet from the boiler, at N the steam exit to the
cylinders, and at P the steam inlet to the brake. When the parts are in the
position shewn in Figure 1, the steam can pass through the valve to the
cylinders, as indicated by the arrows, the said valve closing the passage P for
steam to the brake. It will be seen that if the valve K be moved backward,
the inlet for steam to the cylinders will be closed by the solid parts of the valve
coming opposite the openings in the valve casing, and that the openings k³ will
come in line with and give communication for the steam from the steam pipe M
through the valve to the inlet pipe P to the brakes.
The mechanism acts as follows:-
The parts are shewn in the Drawing in their normal position, steam entering the
cylinders by the pipe M, valve K, and pipe N, the passage P to the steam brake
being closed by the said valve. The wheel C being in contact with the rails or
road by running thereupon, receives a motion of revolution therefrom as the
engine is traversed, and this motion is transmitted to the governor through the
pinions C and d, and spindles D, E, and lugs h. In accordance with the speed at
which the engine is travelling, this governor will therefore (through the cotters)
raise the rod F to a greater or less extent, and actuate the pointer of the dial I to
a corresponding extent, so that by reference to the graduations upon the dial, the
speed of the engine can readily be ascertained. Should the limit of maximum
speed allowed be reached, the collar f will come into contact with the arm ¹ of
the three armed lever, and, assisted by the falling over of the weight on the arm *
of the lever, will through the rod k draw back the piston valve K so as to close the
passage for steam to the cylinders, and open the passage for steam to the brake
through the pipe P, thus at once reducing the speed or even stopping the engine.
The speed being reduced the governor balls fall, and the collar f coming into
contact with the forked arm j¹ of the lever, the parts are restored to their normal
position.
Having now described and particularly ascertained the nature of my said
Invention, and the manner in which the same is or may be used or carried into
effect, I would observe in conclusion that I wish it to be understood that I do not
limit myself to the employment of the particular forms of valve, speed indicator,
and governor illustrated and described, as any suitable valve, indicator, or governor,
may be employed without departing from the nature of my Invention. It will
also be understood that more than one wheel (C²) may be used if desired, but what
I consider to be novel and original, and therefore claim as the Invention secured to
me by the bereinbefore in part recited Letters Patent is,-
In tramway and other road locomotive engines controlling the speed thereof by
acting upon the controlling mechanism by means of a wheel or wheels rolling
upon the rails or road, and separate from and independent of the ordinary carrying
and driving wheels of the engine.
In witness whereof, I, the said Thomas Hunt, have to this my Specification
set my hand and seal, this Fifth day of May, One thousand eight hundred
THOMAS HUNT. (I.S.)