Improvements in Cut-offs for Steam Engines.
Year: 1890

page_text: COMPLETE SPECIFICATION.
Improvements in Cut-offs for Steam Engines.
A communication from GEORGE FUSSELL, of Lockport, New York, United States of
America.
1, ALFRED JULIUS BOULT of 323 High Holborn, London, in the County of
Middlesex, Patent Agent, 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 :--
This improvement relates to cut-offs for steam engines, and it consists in the
peculiar construction, arrangement and combinations of parts hereinafter more
particularly described and then definitely claimed.
The object of this improvement is to provide a cut-off, which will automatically
cut off the steam at the proper point at each stroke to prevent any unnecessary
use of steam and at the same time be durable and readily built at a comparatively
low cost.
In the accompanying drawings-
Figure 1 is an elevation of part of an engine having my improvement.
Figure 2 is a vertical central transverse section of the governor.
Figure 3 is a vertical central transverse section through the line xa, in Figure 1.
Figure 4 is a detail of part of the cut-off with parts removed to show other
parts.
Figure 5 is a perspective detail of part of the cut-off.
Figure 6 is a vertical central section through the valve chest.
Figure 7 is a similar section at right angles to that shown in Figure 6.
Referring now to the details of the drawings by letters and figures-A represents
the cylinder of the engine of any approved form, on the side of which is the
steam chest B, having caps bb, and central partition C dividing it into two parts
for the live and exhaust steam. At each end of the cylinder is a passage D,
(shown in dotted lines in Figures 6 and 7) leading to the ports E, the top of
which communicates with the upper or live steam section of the chest, while the
other communicates with the lower or exhaust section.
The inlet or live steam section is provided with a valve F, and the exhaust with
another valve G, both preferably alike and having suitable valve rods f g. These
valves work between gibs c c, or other suitable guides bolted to the partition C as
shown in Figure 7.
At H, (see Figure 1) is shown a rod operated in any suitable manner by a
connection with the shaft of the engine (not shown) and having an open slot h,
which slips on a wrist pin i on an arm I, which is mounted on a stud J, fixed
to the frame K of the engine. This same pin i carries a link I, whose other end
is pivoted to the valve rod g.
Above the arm I is another arm M, mounted on the same stud (J) that carries
the arm I, and having a pin m that carries a link N pivotally connected to the
valve rod f, so that when these two arms move in unison, simultaneous motion is
given to the valves F G in opposite directions.
At the back of arm M and fast thereon is a pin O and above or below it (at the will
of the constructor) is another pin P fast in the frame of the engine, and bearing on
both sides of these two pins are the ends of a spring Q whose central portion is coiled
around the stud J.
The arm M is provided with a shoulder m' which overhangs the top of the arm I
and is provided with a sliding dog R, which is forced downwards by a spring S into a
hole in the top of the arm I, and is provided with a handler by which it can be
raised out of the hole i when necessary or desired. At the back of the handle is a
D

page_text: toe, which rides over two cut off segments T, (see Figures 4 and 5) pivoted at t to
the frame of the engine and are connected by links U to the governor slides V,
operated by the motion of the ring W, connected to the governor arms X, by the
links Y, in a manner well understood.
Rising from the governor arms X and firmly attached thereto, are two ears 2, each
having a hole in its upper end to receive the ends of a rod 3, around which is a spiral
spring 4, one end of which bears against one of the cars 2 and the other against a
regulating nut 5 which is screwed upon the rod 3, one end of which is threaded for
this purpose. At 6 is shown a collar which is fast on the rod 3 and this collar rests
against one of the ears X as shown in Figures 1 and 2. Motion is given to the
governor by a belt (see Figure 1) which passes over a pulley 7 on a shaft 8, that
carries a bevel gear, meshing with another similar gear 10, on a shaft 11, carrying
the head 12, to which is connected the arms X carrying the balls 13. The shafts 8
and 11 are mounted in suitable bearings 14 and 15 in the casting 16, which is
provided with a flange 17, by which it is bolted to the frame of the engine as
shown in Fig. 1.
The operation is as follows: Steam being admitted to the engine as the shaft
revolves, the rod H gives a vibrating motion to the arm 1, which in its turn gives
inotion to the arin M, by means of the dog R, and these two arms thus give a recipro-
cating motion to the valves G in opposite directions, whereby steam is admitted to
and exhausted from the cylinder in a manner well understood.
As long as the
engine is carrying a load that will keep the engine running at its normal speed,
this action continues, but should there be such a lightening of the load or an
increase in the pressure of the steam as to cause the engine to increase its speed,
the balls of the governor would immediately rise, thus causing the ring W to lift
the segments T, and these latter would act on the toe and lift the dog Rout
of the hole in the arm 1, and thus break the connection hetween the two arms.
The spring (or rather one end of it) now comes into play, and acting on the
pin O, forces the arm M to assume a perpendicular position, thus cutting off the
steam. The arm I, however, continues its motion and as it comes into the per-
pendicular position, the dog R drops into the hole in the arm 1 and thus the
two arms are again connected and the valve F is again given motion in the opposite
direction to open the port to admit steam to the opposite end of the cylinder,
where, if the engine is still running too fast, the same operation is repeated, and
the other end of the spring Q acts on the pin O and again causes the arm M to
assume a perpendicular position and thus cut off the steam from that end of the
cylinder. From this it will be seen that this arrangement makes a perfect
automatic cut off that is not only certain in its operation, but is not likely to get
out of order.
If it is desired to heat the engine before starting, it is only necessary to raise
the handle and thus lift the dog R out of the hole 1, when by pressing on the
handle m", in the desired direction, the valve G may be moved and thus steam may
be admitted to either end of the cylinder, or both in succession as desired.
Below the pivoted end of one of the segments is shown a removable pin 18. If
the engineer should wish to leave the engine room, he should remove this pin, and
should the governor belt break during his absence, the pivoted end of the segments
will drop thus elevating the free ends, which will act on the toe and cut off the
steam, so that all danger from racing, due to the breakage of the governor belt, is thus
prevented.
By adjusting the spring 4, by means of the nut 5, the sensitiveness of the
governor under an increase of speed of the engine may be increased or decreased
at pleasure.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. In a cut off and in combination with inlet and exhaust valves, two arms each

page_text: connected to a separate valve and means for locking said arms together to move
simultaneously or independently, substantially as described.
2. In a cut off and in combination with the inlet and exhaust valves, two arms
locked together to move simultaneously and means for automatically unlocking said
arms, substantially as described.
3. In a cut off and in combination with inlet and exhaust valves, two arms locked
together to move simultaneously and an adjustable unlocking device, substantially as
described.
4. In a cut off and in combination with inlet and exhaust valves, two arms locked
together to move simultaneously, an adjustable unlocking device, and a spring for
returning one of the arms to a perpendicular position when the arms are unlocked,
substantially as described.
5. In a cut off and in combination with inlet and exhaust valves, two arms, locked
together to move simultaneously, an unlocking device and a governor connected with
said unlocking device, substantially as described.
6. In a cut off and in combination with inlet and exhaust valves, two arms, a spring
actuated dog in one locking it to the other, the pivoted segments for unlocking
the same and a connection with the governor for operating said segments, substan-
tially as described.
7. In a cut off and in combination with inlet and exhaust valves, two arms, a spring
actuated dog in one locking it to the other, the pivoted segments T, the rods U, the
slides V working in the standard 16 and operated by the ring W sliding on said
standard, substantially as described.
8. The combination with the reciprocating rod H, the arm I connected thereto, the
arm M connected to the arm I, the valves F G connected to said arms, the dog 1, the
segments T, rods U, slides V and ring W, operated by the motion of the governor
balls, substantially as described.
9. The combination of the standard 16, the slides V moving in grooves therein, the
ring W, acting on said arms and connected to the arms X carrying the balls 13.
10. The combination in a governor, of the balls 13, the arms ✗ having ears 2,
extending above the pivotal point of said arms X and an adjustable spring 4 set
between and acting on the ears 2, substantially as shown and described.
11. The combination of the steam chest B having a central partition C, provided
with triple ended passages therein, communicating with the cylinder and the inlet and
exhaust chambers, with reciprocating valves alternately opening and closing the inlet
and exhaust ends of said passages, substantially as described.
Dated this 10th day of November 1890.
W. P. THOMPSON & BOULT,
Agents for the Applicant.