IMPROVEMENTS IN THE MEANS FOR WORKING THE VALVES AND CONTROLLING THE SPEED OF MOTIVE POWER ENGINES
Year: 1879

page_text: LETTERS PATENT to John Hawthorn Kitson, of Leeds, in the County of York,
Engineer, for the Invention of "IMPROVEMENTS IN THE MEANS FOR WORKING
THE VALVES AND CONTROLLING THE SPEED OF MOTIVE POWER ENGINES."
PROVISIONAL SPECIFICATION left by the said John Hawthorn Kitson at
the Office of the Commissioners of Patents on the 5th November 1879.
JOHN HAWTHORN KITSON, of Leeds, in the County of York, Engineer. "IMPROVE-
MENTS IN THE MEANS FOR WORKING THE VALVES AND CONTROLLING THE SPEED
OF MOTIVE POWER ENGINES."
The first part of my Invention relates to the valve gear of motive power engines,
and consists of an arrangement of parts, the object of which is to give the required
movement to the valve by a combination of a motion derived from the cross head
with a motion at right angles thereto derived from some other convenient part of
the machinery without the intervention of an excentric sheave or its equivalent.
One arrangement consists of a lever, one end of which is coupled by a link or
other suitable arrangement to the cross head and the other to the valve spindle.
To an intermediate point on this lever one end of a radius rod is coupled, the other
end being coupled to a die working in the curved slot of a link pivotted to a fixed
point at about the middle of its length. Opposito this point of attachment the
link is provided with a tail piece, the end of which is connected by a link rod with
a point on the connecting or coupling rod of the engine as may be most convenient.
The slotted link is furnished with pivots at or near to the centre line of the curved
slot, and a bracket or other suitable means is provided for carrying these pivots in
a certain fixed position, thus forming a fulcrum on which the curved slotted link
oscillates.
By means of an ordinary weigh bar shaft and lifting links the die can be placed
in such a position in the slotted link as will give any desired amount of expansion
or a reversed motion.
In some cases, instead of coupling the connecting or coupling rod direct to the
tail piece of the link, I attach one end of a link rod to the coupling or connecting
rod, whilst to the other end of this rod I joint a second link rod which I connect
to the tail piece.

page_text: The second part of this Invention relates to an arrangement of apparatus for
controlling the speed of engines, more particularly tramcar and locomotive engines.
On an axle of such an engine I fit two discs, one of which is keyed fast while the
other is free to slide on a feather. Between these discs I place a loose pulley, to
which is attached a chain leading to a brake apparatus and also connected with
the throttle valve.
I also fix on the opposite sides of the axle two pivots which form centres for two
rock levers. Between the extremities of these levers two weights are fastened, and
I also attach a pin or fulcrum near the middle of their length, which I couple by
means of links with corresponding pins in the sliding disc before mentioned.
Opposite to one of the weights and on the other side of the axle I fix a T shaped
piece carrying springs in tension, which are connected at their other ends with the
opposite weight.
The tension on these springs is such that until the required limited speed is
exceeded no action takes place, but when it is exceeded the centrifugal force of the
weights overcoming the resistance of the springs will cause the disc to slide forward
on the axle and grip the loose pulley between it and the fixed disc, thereby causing
the pulley to wind up the chain. The tension thus put on the chain, which is
attached both to the brake and the steam valve, will simultaneously put on the
brakes and shut off the steam, and thus prevent any required speed being exceeded.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Hawthorn Kitson in the Great Seal Patent Office on the
5th May 1880.
JOHN HAWTHORN KITSON, of Leeds, in the County of York, Engineer. "IMPROVE-
MENTS IN THE MEANS FOR WORKING THE VALVES AND CONTROLLING THE SPEED
OF MOTIVE POWER ENGINES."
This Invention relates, firstly, to a novel arrangement of valve gear for motive
power engines, the object being to give the required "supply," "cut off," and
"reverse" motions to the valves by a combination of a motion derived from the
cross head with a motion at right angles thereto derived from some other con-
venient part of the engine, without the intervention of an excentric or its
equivalent specially provided for the purpose; secondly, to apparatus for con-
trolling the speed of tramcar and other locomotive engines, by bringing into action
a friction brake and cutting off the steam automatically so soon as a given speed is
exceeded. In Sheet I. of the accompanying Drawings the first part of my Invention
is shewn as applied to a locomotive engine, and in Sheet II. as applied to a marine-
engine, a slight modification in the apparatus being made for this purpose. In both
arrangements the same letters of reference are employed to indicate like parts.
A is the steam-cylinder; B, the cross-head; and C, the rod by which the cross-head is
connected to the crank D of the driving wheel (Sheet I.) or crank-shaft (Sheet II.);
E is a lever which is pivotted at its upper end to the rod F of the slide valve, and
is connected at its lower end by a rod G to the cross-head B. This lever is also
connected near its upper end by means of a rod H with the ordinary slotted link I,
which is mounted on a suitable standard or support so that it may pivot on a
central trunnion I*. The rod H is pivotted to a sliding block which fits in the
segment shaped slot of the link I, and is free to be set in any desired position in
the slot by means of the rock bar, levers, and links K, K, in the manner common
to link motions. Projecting from the slotted link I and forming one piece there-
with is a tail piece I', which is connected by a rod L with the head of the connecting
rod C.
From the foregoing description of the parts it will be understood that when the
engine is set in action the connecting rod C will impart, through the rod L, an
oscillating motion to the slotted link I, and at the same time the cross head B will,
by reason of its connection through the rod C with the lever E, impart a rocking
motion to that lever. The Drawing shews the sliding block of the link I at its
dead point, but when shifted to either side thereof the link in its oscillations will
cause the rod H to actuate the lever E and move the slide valve with which it is
connected, thereby admitting steam to and cutting it off from the cylinder as
required.
The action of the link motion as respects the movements of the slide-valve will
be similar to that of the link motions in common use, but the mechanism employed
for imparting motion to the slotted link will by this Invention be greatly
simplified.
In the arrangement shewn in Sheet II., instead of connecting the tail I¹ of the
link I with the crank rod C by means of the rod L, an intermediate rock lever M
and rod N are employed, the lever M having its fulcrum on an independent
standard. This modification is introduced as a convenient means for communi-
cating the motion from the crank rod to the slotted link.
The second part of my Invention is illustrated in Sheet III., Fig. 1 being a side
view of the apparatus by which the motion for putting on the brakes and for
cutting off the steam is obtained, and Fig. 2 being a cross section of the same taken
in the line 1, 2, of Fig. 1.

page_text: Upon the axle A of one pair of travelling wheels of a locomotive or tramcar
engine a friction disc B is keyed. This axle is provided with a feather for receiving
a similar friction disc C, which is capable of sliding freely towards and from the
fixed disc. Between the two discs is mounted loosely upon the axle A a pulley D,
to which a chain E is attached in such manner as to allow of its being wound up
upon the pulley when rotary motion is imparted thereto. By connecting this
chain E with a brake and with a lever in connection with the steam-supply valve
any tension put upon the chain by the pulley will throw the brake into action and
cut off the steam, thereby instantly checking the progress of the engine. The
rotation of the pulley D to effect the winding up of the chain E is produced by the
gripping of the pulley between the discs B and C while the axle A is in rapid
rotation. This gripping of the pulley is effected automatically by the following
means-Pivotted to the axle A is a rocking frame F which is weighted at its
extremities to give the frame a tendency, as the speed of rotation of the axle A
increases, to move to a position at right angles to the axle. This tendency is
counteracted by means of coiled springs G, which tie one end of the frame elastically
to a fixed T-piece H projecting from the axle A. The strength of these springs
will be such as to retain the frame in its normal position, as shewn in the Drawings,
so long only as the axle A rotates at its proper minimum speed. When this speed
is exceeded the springs will yield to the centrifugal action of the loaded frame, and
the frame will then move on its pivots in the direction of the arrow in Fig. 1.
I, I, are rods which serve to connect the disc C with the oscillating frame F. When
therefore this frame is caused to take the dotted position Fig. 1 the disc C will by
means of the connecting rods I be thrust forward against the loose pulley D, which
will be gripped firmly between the two friction discs and caused to rotate therewith.
This rotation of the pulley D will put such a tension on the chain E as to bring
the brake in connection therewith into action, and to shut the steam supply valve.
have not thought it necessary to trace the connection of the chain E with either
the brake or the steam supply valve, as that will vary according to the arrange-
inent of the engine and the brake apparatus employed. The manner however of
effecting this connection will be obvious to any competent mechanic whatever may
be the controlling circumstances of the case.
Having now set forth the nature of my Invention of "Improvements in the
Means for Working the Valves and Controlling the Speed of Motive Power Engines,"
and explained the manner of carrying the same into effect, I wish it to be under-
stood that under the above in part recited Letters Patent I claim,-
First. The means above described for obtaining the motion for working the slide-
valves of motive power engines from the cross heads and cranks of such engines.
Second. The means above described for obtaining automatically the motion for
controlling the speed of tram-car and other locomotive engines.
In witness whereof, I, the said John Hawthorn Kitson, have hereunto set my
hand and seal, the Seventeenth day of April, in the year of our Lord One
thousand eight hundred and eighty.
J. HAWTHORN KITSON. (LS.)