AN IMPROVEMENT ON STEAM ENGINES AND OTHER MACHINERY WHERE THE CRANK IS USED
Year: 1821

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ALDERSEY, of Hommerton, in the Parish of Hackney, in the County of Mid-
dlesex, Gentleman, send greeting.
WHEREAS His most Excellent Majesty King George the Fourth did, by
His Letters Patent under the Great Seal of that part of the United Kingdom
of Great Britain and Ireland'called England, bearing date at Westminster, the
Third day of February, in the second year of his reign, givé and grant unto
me, the said William Aldersey, my exors, adññiors, and assigns, His especial
licence, full power, sole privilege and authority, that I, the said William
Aldersey, my exors, adññors, and assigns, during the term of years therein
mentioned, should and lawfully might make, use, exercise, and vend, within
England, Wales, and the Town of Berwick-upon-Tweed, and also in all His
Majesty's Colonies and Plantations abroad, my Invention of "AN IMPROVEMENT
ON STEAM ENGINES AND OTHER MACHINERY WHERE THE CRANK IS USED;" in which
said Letters Patent there is contained a proviso that if I, the said William
Aldersey, shall not particularly describe and ascertain the nature of my said
Invention, and in what manner the same is to be performed, by an instrument
in writing under my hand and seal, and cause the same to be inrolled in His
Majesty's High Court of Chancery within four calendar months next and
immediately after the date of the said Letters Patent, that then the said
Letters Patent, and all liberties and advantages whatsoever thereby granted,
shall utterly cease, determine, and become void, as in and by the same,
relation being thereunto had, will more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
William Aldersey, do hereby declare that the nature of my said Invention,
and the manner in which the same is to be performed, are particularly described
and ascertained in and by the Drawings hereunto annexed, and the following
description thereof (that is to say):-
Instead of making use of a revolving crank and a connecting rod to con-
nect the fly wheel or other wheel or wheels or machinery to which I am
desirous of giving rotatory motion with the prime mover, which I presume to be
of such kind as to produce alternating or reciprocating motion, as in the steam
engine, I connect the same either immediately or through the means of a beam,
by the means of cogged or toothed wheels, or segments of wheels, and a frame
containing a double rack or pair of racks, which are also cogged or toothed,
with a degree of strength correspondent with the power of the machine or
force which it has to overcome, the form and disposition of such wheels and
racks, with respect to each other, being more clearly shewn and exemplified in
the Drawing hereunto annexed, in which A, Figure 1, represents a part of a
shaft to which it is proposed to communicate rotatory motion. A fly wheel
B, B, is shown in the Drawing fixed upon the opposite end of that shaft, and
this may be adopted or not, as may be found necessary for the machinery, but
forms no part of my Invention; but I prefer its use for equalizing the power,
and therefore I usually retain it in all cases where it has been used before.
Upon some convenient part of the main shaft A, I firmly fix a metal wheel.
having teeth of the description commonly known by the name of ratchet or
click teeth, the position of such ratchet wheel being shewn in the Drawing
at C. This wheel must be so firmly attached to the shaft upon which it is
placed, either by fitting up on a square or otherwise, that it cannot turn or move
without causing the said shaft to move or turn also. On either side of this
last-mentioned ratchet wheel I apply a cogged wheel of larger diameter than
the ratchet wheel aforesaid, and of sufficient strength to overcome the resist-
ence of the machine whatever it may be. Those two last-mentioned cog
wheels, shewn at D, E, in the Drawing, having a reciprocating motion on the
said shaft, move upon the same common center of motion as the shaft and
ratchet wheel, but they are not fixed or attached to such shaft but are free to
revolve upon it, and for this purpose those parts of the shaft upon which they
hang or turn are turned truly smooth and cylindrical, and the centre holes of
these wheels are. made to fit truly upon such cylindrical bearings on the said
shaft. The wheels D, E, are likewise to be kept in such close contact with
the ratchet wheel C as merely to let the one move past the other without
strain or friction, which is to be prevented by means of bosses, shoulders,

page_text: washers, keys, cotters, or other well known means applied to or placed upon
the said main shaft A, both between the insides and at the outsides of both
the said wheels D and E, and the ratchet wheel C. A click or pall is shewn
at i, the same being firmly attached to the inside of the wheel D upon a
center, in such manner that it may turn or move in a portion of a circle,
and that its end which so moves may fall into, and lay hold of, the ratchet
wheel C; and is a spring fixed on the inside of the wheel D, pressing on
the back or outer side of such pall to insure its due and proper action into
such teeth; a similar pall or click and spring is in like manner affixed to the
inside of the wheel E, but this cannot, of course, be shewn in the annexed
Drawing on account of the opacity of that wheel. It will now be seen, that
if the wheels D and E are required to move more than about between one
third or one fourth part round in opposite directions, the clicks or palls and
springs will run foul of or come into contact with each other, even though they
may be set or affixed to opposite points in the two wheels, and, consequently,
that the ratchet wheel C must be of sufficient thickness or width to permit the
palls or clicks of both the wheels D and E to take into its two opposite sides
without permitting the possibility of the said two palls or clicks, or the bolts,
pins, or other contrivances by means of which they may be affixed to the sides
of the aforesaid two cog wheels ever coming into contact or touching each
other; and in some cases it may be convenient to make the ratchet wheel
even wider or thicker than this would require, by which the cog wheels D and
E may be placed and fitted at any required distance, as under, on the said shaft,
and by which a facility will be afforded of getting at the palls and springs to oil
and repair them when necessary. F, F, is a strong frame of timber, metal, or
other suitable material, which may be made in one or more pieces and shaped
as in the Drawing, or finished with circular, elliptical, or other ends, or may be
open at one of its ends; one end of this frame is to be connected as at G, by
a universal joint, or in any other convenient manner, to the end of the beam or
lever, which is supposed to be thrown into reciprocating or alternating recti-
lineal motion by the steam engine or other prime mover; or by supposing the
Drawing to be inverted, the part H may be conceived to represent the piston
rod of a steam engine, which may thus be made to act immediately upon its
work without the intervention of a beam, parallel motions, or any of those parts
which introduce much friction and vis inertia into the machine. The whole of
this frame moves alternately up and down, and may be guided in such motion by
the side cheeks or pieces I, I, I, I, which may, if necessary, have friction rollers
or wheels fixed to them, for the purpose of diminishing friction; or if it is.
connected by a parallel motion apparatus, or so disposed as to move up and down

page_text: in a rectilineal direction, the whole may be guided by the piston rod itself, or
by two or more turned or other rods like H placed above and below the frame,
or, for instance, one at H and one or two passing into the holes L, L, the
whole of which must be made to slide through steadying holes in the frame-
work above and below; but if the frame is working in the form shewn in the
Drawing, and is not attached to the beam by a parallel motion apparatus, or
has not a direct up and down motion, then it must be kept in its place by
rollers, and have liberty to sweep so as to allow of lateral motion, which will
not be detrimental to its action. This frame F, F, is for the purpose of
carrying two toothed racks, one of which is clearly seen at K, and a part of
the teeth of the other at M. These toothed racks are not opposite to each
other, but are so placed and fixed in the frame, or may be made in one piece
with the frame itself, as to take correctly into the teeth or cogs of the two
wheels D and E; thus the rack K takes into the teeth of the wheel D, while
M takes into E, the consequence of which is, that whenever the frame and
racks are moved either upwards or downwards either in a large or small
degree, circular motion will be given in an equal degree to both the cog wheels
D and E, but in opposite directions, for while one moves to the right
the other will move to the left, and vice versâ, on account of the racks. being
placed on opposite sides of the shaft which is to be moved; and since they
have this alternate motion, it is evident that the pall or click of one wheel
will be pushing against or acting upon the teeth at one side of the ratchet
wheel to drive it round, while the pall or click of the other cog wheel will be
drawn backwards over the opposite side of the same ratchet wheel in the direc-
tion in which it can produce no action on the teeth, and, consequently, whether
the frame F, F, is moved upwards or downwards, it will constantly have the
effect of moving the ratchet wheel round, together with the shaft to which it
is attached as aforesaid; and whether the stroke of this frame be great or
small (provided it is sufficient to carry the palls over a single ratchet tooth),
the effect will be the same, without any cessation or discontinuance of action.
Such is the principle of my Invention, the application of which cannot fail of
being understood by the single case or form of it above described; but it will
be evident to any mechanic that it admits of a variety of forms and applica-
tions; thus, for example, the frame instead of moving vertically may be placed
in an horizontal or even an oblique position, and the power may conse
quently be applied from above, from below, or from either side. The advan-
tages of this Invention for converting, alternating, or reciprocating rectilineal
into rotatory motion over and above the common crank, which is generally
used for this purpose, are,-
2)
..

page_text: 1st. That the power from the prime mover, by being always applied at the
extremity of the radius of the wheels D and E, is uniform and equable, and
is not attended with that great loss and inequality from which the crank is
inseparable, by varying its leverage from nothing at the center to its full
extent when at right angles to its rod of connection.
2ndly. That in many constructions of machinery it is essential that the main
shaft should always revolve in the same direction, which cannot be insured by
the crank, but it is securely provided for by. my Invention, as already described.
3rdly, The power may be applied either from above or below, or laterally,
with equal advantages, and does not require that nicety of adjustment which
the crank does. And,
4thly. While the crank requires one constant and equal quantity of motion,
or length of stroke in every alternation of the prime mover, in order to produce
rotatory motion, my Invention will communicate such motion, even though such
mover may be irregular or have varying motion. I am not, therefore, bound
to any particutar length of stroke, and as my ratchet wheel or wheels D and E
have not the same relation in diameter to the length of stroke that the crank
has, I can increase or diminish their size at pleasure, and thus not only alter
the speed of my machine but cause the power to be applied at different (lis-
tances from the center of the main shaft A, which is attended with many prac-
tical advantages. . It may, however, in many instances, be necessary to limit
or ascertain the stroke of the steam engine or other prime mover to which my
aforesaid Invention may be applied, as well as to change the direction of the
revolution of the main shaft, both of which objects are accomplished without
difficulty in the following mianner-To limit or determine the stroke, it is
necessary to limit or determine the motion of the frame F, F, and this I do
either by connecting some part of that frame by means of an ordinary swinging
connecting rod with a crank and fly wheel, as shewn by dotted lines in the
Drawing at N, N, N, or else, if a beam is used, I connect some part of that
beam to such crank and fly wheel, by which, in either case, the length of
stroke of the machine will be limited and determined, and may be made suit-
able to the stroke or motion of the machine to which it is applied. In those
cases where it may be necessary to change or reverse the direction of the
motion, I use a double set of ratchet or click wheels, (that is to say), in addition
to the one click or wide wheel C placed between the two cogged wheels D, E;
I. likewise use two other ratchet or click wheels, which may be of the same
diameter or not as the central wheel C, but of equal strength, and these two
additional wheels have the points of their teeth pointing in the reverse direc-
tion of the central click wheel C, and are applied and used one on the out
or exterior side of each of the cog wheels D and E, as will be seen at Fig. 2,

page_text: which represents a longitudinal section through the wheels at the main shaft,
with one central and two exterior or reversing click wheels. The same
letters of reference are used in this Figure as in Fig. 1, therefore, A repre-
sents the main shaft; B, a fly whcel upon its end; C, the central click wheel;
D and E, the two cog wheels taking into the racks (one ouly of which is
shewn at K; F, part of the frame for carrying the racks i, i, the clicks or
palls acting into the central ratchet wheel C; , the springs for pressing on
the palls or clicks; N, O, the two exterior or reversing ratchet wheels, with
their teeth in opposite directions to those of the central ratchet wheel; p², the
palls or clicks which act into them, and which of course point in an opposite
direction to those palls on the other side of the same wheel, which act into the
central wheel. In the use of this Invention it is evident that the interior
palls i, i, and the exterior ones p, p, when two sets are so applied and used,
must never be in action at the same time, for this would produce the effect of
locking the machine and preventing its moving at all. It is therefore neces-
sary, when a reversing motion is adopted, to pay particular attention not only
to the situation of the palls, but to the form of the ratchet teeth, for in this
case their acting faces must not overhang, but they must be made to point
in the direction of radii of the ratchet wheel, as shewn at y, z, Fig. 3, other-
wise it will be impossible to withdraw the points of the palls or clicks from
the said teeth, when the machine is in action, without moving it backwards to
disengage them; but when the machine is required to move in one way only,
the reversing wheels are not introduced, and no such attention will be neces-
sary, since the machine cannot go wrong, In order, however, to prevent
accidents when the double motion is adopted, I use an ecentric lifter, which
admits of many forms, but that shewn at 7, r, s, Figs. 3 and 4, is as simple as
any, Fig. 3 being a front view on a large scale of such lifter, with part of
the external ratchet wheel O, its click or pall and springs p, k, as fixed upon
the outside of the cog wheel E, the pall p being shewn as if in action in the
teeth of the ratchet wheel O. The internal pall or click, or that which is
fixed on the other side of the cog wheel E, and, consequently, would be
invisible in this Figure, is drawn in red ink at i, to shew the situation it must
be in when the external pall or click p is down or in action, by which it will
be seen that when p is down i is elevated, and taken completely out of the
reach of the teeth of the internal ratchet wheel C (also drawn in red ink).
The manner in which this disposition of the palls takes place will be obvious
when the construction of the excentric lifter is considered, for it consists
of a cylindrical steel or other axis q, passing through the cog wheel E. by
means of a hole fitting it pretty accurately, and in which it turns round
friction-tight.

page_text: Fig. 4 shews a section of part of the cog wheel E, together with the cylin-
drical axis of the lifter q, and the two eccentric pallets and s, which
fit on to squares at the two ends of the cylindrical axis q, and so are
fixed that one pallet may project upwards while the other projects downwards,
as will be seen in both the last Figures. From the situation of the two
eccentric pallets of the lifter in Fig. 3, it will appear that the pall or click
p is not affected, because the projecting part of the front pallett is turned
is turned downwards the
downwards and cannot reach it; but when
projecting part S of the inner pallet (drawn in red ink) will be upwards,
and consequently will throw the inner pall or click i into the elevated
situation in which it is shewn in the Drawing. By turning the axis q
half round the position of the palls will be reversed, for now p will be
clevated and relieved while i will descend and come into action. The
square t, on the end of the axis q, is for turning it by means of a socket key,
spanner, or fixed lever, and the excentric pallets whenever moved are retained
in their proper or required situations by the studs or projections on the pallets
near and s falling into corresponding notches formed in the under side of
the palls for the purpose of receiving them; the springs k, k, prevent the studs
from being disengaged from the notches by the motion of the machine, but a
small force applied at the square t will be sufficient to disengage them if the
ratchet teeth are properly formed, as herein-before described. *
As the perfection and security of my Invention depends in a great measure
on the freedom of motion of the palls or clicks, and at the same time on their
strength and inability to give way, I sometimes use two palls or clicks to each
of the cogged wheels, one of which may be suspended or not at pleasure, and
some attention is necessary to the manner of attaching them to the cog wheels
D and E, and accordingly I prefer a bolt, having a strong square shank, with
a collar upon it to fit tight into a hole in the wheel, so that it may pass
entirely through such wheel and be secured by a nut screwed and pinned
through on the external part of the said wheels, so as to prevent the possi-
bility of its unscrewing while the pall or click itself turns on the cylindrical
projecting end of the said bolt, as shewn at æ, Figure 6. In case of the
wheels D and E being made of cast iron, a housing bed or recess, as shewn
at Figure 5, may be formed in the face of the wheels, so as to fit round the
back part of the pall, and thus to form an abuttment for it to rest against in
case its pivot bolt should bend or begin to give way. The view of the main
shaft and the sections of the wheels, as shewn at A in Figure 2, will give
sufficient information as to its form and the mode of hanging and arranging
the several wheels. The central part A, for instance, must be square or poly-
gonal for the central ratchet wheel C to be fixed upon, and this may be

page_text: thicker than any other part of that shaft, so as to form shoulders for the
wheels D, E to rest. against, and the parts v, v, must be round or cylin-
drical for the wheels D, E to turn upon. These are all the shoulders
that will be necessary, unless when the reversing motion is used, and
in that case two more square or polygonal parts w, w, must be formed for
the external ratchet wheels N and O to be fixed upon; and those wheels
may be secured in their places by the washers x, x, which may be screwed
on, or, what is better, be made secure by cross wedge keys driven through
them, as shewn in the Figure. The cylindrical bearings y, y, must in
all cases be formed, since they are for the shaft to revolve upon in its
plummer blocks =,=. I do not however bind myself to this form of shaft,
since any mechanic will see that it may be varied in form and con-
struction with equal effect, and I therefore merely describe it as one form
which may be adopted; and for the same reason segments of toothed wheels
may be used instead of the entire wheels D, E, provided such segments
contain a sufficient number of teeth to answer to the length of stroke that
the machine may require. The framework and other parts of the machine
likewise need not follow the form given in the Drawing, but will of course
require to be varied to suit the circumstances of its application, the
whole of my Invention and all that I claim to be secured to myself, my exors,
adiñors, and assigns, by my herein-before in part recited Patent, being
the application of the force and motion of the prime mover at the extreme
radius of two wheels, by means of the racks herein-before described, and
the transfer of that force and motion to the central shaft by the agency of
the ratchet wheel and wheels D and E, and the palls or clicks, thus producing
a uniformly powerful action, instead of the variable and frequently ineffectual
action of the crank; and as this may be done in the manner and upon the
principles above described, both in large and small machinery, and in wood,
metal, or other materials, it becomes unnecessary for me to describe the
dimensions of the several parts or the materials I make use of, as these and
the form and disposition of the framework and wheels must be suited to
the situation in which they are applied, and must admit of many modifications.
The above description will, however, enable a competent workman to apply
my aforesaid Invention to every case that can occur.
In witness whereof, I, the said William Aldersey, have hereunto set my
hand and seal, this Second day of June, in the year of our Lord
One thousand eight hundred and twenty-one.
W. (L.S.) ALDERSEY.

page_text: AND BE IT REMEMBERED, that on the Second day of June, in the year
of our Lord 1821, the aforesaid William Aldersey came before our said Lord
the King in His Chancery, and acknowledged the Specification aforesaid, and all
and every thing 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.
Inrolled the Second day of June, in the year of our Lord One thousand
eight hundred and twenty-one.