IMPROVEMENTS IN CERTAIN AGRICULTURAL IMPLEMENTS, AND IN STEAM ENGINES AND BOILERS FOR DRIVING THE SAME
Year: 1851

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
WILLIAM EXALL, of Reading, in the County of Berks, Engineer, send
greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by
Her Royal Letters Patent under the Great Seal of the United King-
dom of Great Britain and Ireland, bearing date at Westminster the
First day of December One thousand eight hundred and fifty-one, in the
fifteenth year of Her reign, did for Herself, Her heirs and successors,
give and grant unto me, the said William Exall, my executors, admini-
strators, and assigns, Her especial licence, full power, sole privilege and
authority, that I, the said William Exall, my executors, administrators,
and assigns, or such others as T, the said William Exall, my executors,
administrators, and assigns, should at any time agree with, and no others,
from time to time and at all times during the term of years therein ex-
pressed, should and lawfully might make, use, exercise, and vend,
within England, Wales, and the town of Berwick upon Tweed, my
Invention of IMPROVEMENTS IN CERTAIN AGRICULTURAL IMPLEMENTS, AND
IN STEAM ENGINES AND BOILERS FOR DRIVING THE SAME;" in which said
Letters Patent is contained a proviso that I, the said William Exall,
shall cause a particular description of the nature of my said Invention,

page_text: and in what manner the same is to be performed, by an instrument in
writing under my hand and seal, to be inrolled in Her Majesty's High
Court of Chancery with six calendar months next and immediately
after the date of the said in part recited Letters Patent, as in and by the
same, reference being thereunto had, will more fully and at large
appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
William Exall, have ascertained and set forth the nature of my Inven-
tion, and the manner of carrying the same into effect, in and by the fol-
lowing description thereof, reference being had to the drawings hereunto
annexed, and to the figures and letters marked thercon, observing that
when two or more figures are given of the same object, the same letters
denote the same parts in the several figures.
My improvements in certain agricultural implements relate to the
construction of chaff-cutting machines, threshing machines, and reap-
ing machines.
Figures 1, and 2, represent my improvements in chaff cutters, which
refer to the mode of compressing and conveying the chaff material to
the cutters, and to the construction of the journals and bearings of the
cutter spindle.
Figure 1, is a section of the feeding apparatus; a, a, are two endless
chains, passing round rollers b, b, and placed at an acute angle with each
other. In lieu of these chains, endless belts or bands composed of
webbing, canvas, coir, matting, or other textile fabric, with or without
battens attached thereto transversely, may be employed; but I prefer
constructing them of two or more endless chains, as shown in the
figure, with the joint pins a', a', of the breadth of the feeding trough,
and passing from side to side through the several chains. The webs
or chains are driven by means of any convenient connexion with
the driving shaft, and when caused to revolve in the direction of the
arrows compress the straw or chaff' material, and carry it forward to the
knife or cutter c.
Figure 2, represents the cutter and cutter spindle, with the spindle
bearings; c, is the cutter, and 7, the spindle, which is formed with jour-
nals at d¹, d, of a tapering form, which revolve in suitably formed

page_text: bearings in the frame; e, is a tightening nut and washer, for the purpose
of drawing up the spindle, as the bearings wear away.
Figure 3, exhibits my improvement in threshing machines, which
consists in conveying the straw into the hopper by means of an endless
band or web; a, is the beater drum; b, the concave; c, the hopper, or
feeding place; d, the endless band or web, composed of canvas, felt, or
other suitable material, upon which the straw is laid to be conveyed to
the hopper; e, e, rollers round which the web passes, and which are
driven in any convenient manner by the driving shaft of the machine.
Figures 4, and 5, represent my improvements in reaping machines;
Figure 4, being a plan, and Figure 5, a side elevation of the same; a, is
the general framing, 6, the driving wheel, and c, c, the gauge wheels;
d, d. cutters fixed to an endless band or chain revolving upon the
wheels c, c, and driven by the wheel b, and the intermediate wheels f.ff;
9, 9, is a row of holding spikes attached to the main frame a, and through
which the cutters pass at nearly right angles; h, is an endless cloth on
to which the material falls as it is cut; i, i, the rollers round which this
cloth passes, driven by the band wheel j, on the main wheel; k, is
another cloth or web, moving round rollers 1, 1, at right angles to h, and
driven by the pinion m; n, is the pole, with whipple-tree, to which the
horses are attached. In certain cases, as in windy weather, and with
short slippery material, I dispense with the carrying cloths, and sub-
stitute for them the gathering machine or "collector" P, which is
constructed as follows: p, is the axle, constituting the frame or support
of the machine; 1, 7. tines supported on a swinging frame, q', q', moving
upon the axle p; r, a scraper, likewise moving upon the axle p; s, a
lever supported by a standard t, attached to the axle p, and to the shaft
frame, by means of which the collector can be attached to the reaping
machine, or the collector may be detached, and, by adding to the shafts
frame a pair of the usual shafts, may be drawn separately by a horse;
w, w, are connecting rods, to lift the tines and to depress the scrapers
simultaneously.
My improvements in steam engines and boilers relate to the con-
struction of the boilers, the position and arrangement of the cylinders,

page_text: to the slide valve, the governor, the condensation of the exit steam,
and to the engine carriage.
Figure 6. is an elevation (partly in section) showing my improve-
ments in the construction of boilers: a, is the fire-box, b, the body of
the boiler, and c, the fire tubes; d. an external casing surrounding the
body of the boiler, and communicating with the smoke box e, so as to
form a return flue, through which the heated gases from the fuel pass,
in their way to the chimney; in their passage they impinge upon the
body of the boiler, and upon the cylinder or cylinders f, situated within
the smoke box, and thus heat the exterior of the boiler, and also
increase the effect of the expansive action of the steam in the cylinders.
Figure 7, represents my improved governor: a, is a small double-
acting forcing pump, worked in any convenient manner from the engine;
b, b, are the inlet valves by which air. water, or other fluid is drawn in;
and c, c, the delivery valves by which the fluid is expelled from the pump,
and, passing along the passage d, enters the regulating cylinder e, by the
aperture f; the regulating cylinder has a piston, g, the rod of which is
connected with the throttle valve, also a spring h, or other resistance, by
which the piston is pressed inwards. At the back end of the regulator
is a regulating cock , for the escape of the fluid. The action is as fol-
lows the regulating cock being partially opened, the fluid and the
pump set in motion, a portion of fluid is injected into the cylinder at
each stroke of the pump, and a portion likewise passes out at the
regulating cock; if the engine and pump move too fast, the fluid accu-
mulating in the regulator forces the regulating piston outwards, and
closes the steam passage, and thereby reduces the speed, and vice versa.
Figure 8, represents in section my improved slide valve, the object
of the improvement being to take off or diminish the pressure of
the steam upon the back of the valve: a, is the slide case, and b. the
cover of the same; c, the slide, having a ring d, cast upon the top or back
of it; c, a loose ring fitting easily upon the ring d, and sliding in a steam-
tight manner over the face of the slide case cover as the slide moves to
and fro, the ring and cover being properly faced for this purpose; ff. are
packing rings, preferably formed of vulcanized India-rubber, to prevent
the steam passing between the ring d, and the ring ey, is a hole in the

page_text: cover, to admit the atmosphere to that portion of the back of the slide
which is enclosed within the ring d.
Another portion of my improvements consists in an arrangement for
condensing a portion of the exit steam. For this purpose a descending
branch pipe is carried from the blast pipe to a chamber or vessel
through which the feed water from the tank passes to the feed pump,
and the steam coming in contact with the water, a portion of the steam
is condensed, and the temperature of the water is proportionably raised.
Another improvement consists in the employment of two trunk
engines set at right angles or nearly so, and acting upon a single crank
on the driving shaft, as shown in Figure 9, with a view to compactness
and saving of space.
Another improvement consists in supporting travelling engines for
agricultural purposes upon two wheels only, with adjustable crutches at
either end of the machine to support it when in action; by this ar-
rangement a great reduction of weight is effected, with economy in the
construction, and a lighter draft.
My last improvement consists in the arrangement of the parts of a
fixed engine for agricultural purposes, shown in Figures 10, 11, 12, and
13, in which the whole of the working parts are comprised within or
supported upon a cylindrical frame, the whole being complete and
easily removable.
Having thus ascertained and set forth the nature of my Invention,
and the manner of carrying the same into effect, I claim, in respect
thereof,-
Firstly, the employment of two endless chains, webs, or other
suitable flexible surfaces to convey the straw or other material to the
knives or cutters of chaff-cutting machines, as herein-before described.
Secondly, the giving to the bearings and journals of the spindle of the
cutters or knives of chaff-cutting machines a tapering form, as herein-
before described.
Thirdly, the employment of an endless web to convey the straw to
the hopper of threshing machines, as herein-before described.
Fourthly, the reaping or cutting grass or corn by a continuous
movement, either by means of a series of cutters carried by an endless

page_text: revolving chain or band, as herein-before represented and described, or
by a series of circular cutters, each revolving upon a separate spindle
or axle.
Fifthly, the employment of two endless revolving carrying webs or
cloths (moving at, or nearly at right angles to each other), one of
which receives the material as it cut, and conveys it to the other,
which latter delivers it at the side of the machine.
Sixthly, the construction of the collector," or rake, in which the
axletree is made to constitute the general frame or support of all the
parts; also the causing the scraper to move simultaneously with and
opposition to the tines, in order to the more speedy and effectual
removal of the material from the tines.
Seventhly, the enclosing the body of the boiler of portable agricultural
steam engines in a casing which serves as a return fluc, through which
the heated air and gases pass, in their passage to the smoke box and
chimney; also placing the cylinder in a smoke-box on the upper part
of the boiler.
Eighthly, the mode, herein-before described, of relieving a portion of
the slide valve from the pressure of the steam.
Ninthly, the improved regulator or governor, herein-before described,
for regulating the speed of the engines.
Tenthly, the arrangement, herein-before described, for condensing a
portion of the exit steam.
Eleventhly, the employment of two trunk engines set at an angle
to each other (preferably at an angle of 90°), and both working on one
and the same crank on the driving shaft of the engine.
Twelfthly, mounting the boiler of moveable agricultural engines upon
two wheels, as herein-before described.
Lastly, the general arrangement of the parts of a steam engine for
agricultural purposes, shown in Figures 10, 11, 12, and 13.
In witness whereof, I, the said William Exall, have hereunto set
my hand and seal, this First day of June in the year of our
Lord One thousand eight hundred and fifty-two
3
WILLIAM EXALL. (L.S.)

page_text: AND BE IT REMEMBERED, That on the First day of June in the
year of our Lord 1852, the aforesaid William Exall came before our
said Lady the Queen in Her Chancery, and acknowledged the specifi-
cation aforesaid, and all and everything therein contained and specified
in form above written; and also the specification aforesaid was stamped,
according to the tenor of the Statute made for that purpose.
Enrolled the First day of June in the year of our Lord One thou-
sand eight hundred and fifty-two.