CERTAIN IMPROVEMENTS IN THE MAKING OF LOCOMOTIVE AND OTHER STEAM ENGINES
Year: 1837

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPH
WHITWORTH, of Manchester, in the County of Lancaster, Engineer, send
greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Second day of November, One thousand eight hundred and thirty-
seven, in the first year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Joseph Whitworth, Her especial license, full
power, sole privilege and authority, that I, the said Joseph Whitworth, my
executors, administrators, and assigns, and such others as I, the said Joseph
Whitworth, my executors, administrators, and assigns, should at any time agree
with, and no other, from time to time and at all times during the term of years
therein expressed, should and lawfully might make, use, exercise, and vend,
within England, Wales, and the Town of Berwick-upon-Tweed, my Invention
of "CERTAIN IMPROVEMENTS IN THE MAKING OF LOCOMOTIVE AND OTHER STEAM
ENGINES;" in which said Letters Patent is contained a proviso that I, the
said Joseph Whitworth, shall cause a particular description of the nature of
my said Invention, and in what manner the same is to be performed, to bo
enrolled in Her Majesty's High Court of Chancery within 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
Joseph Whitworth, do hereby declare that the nature of the said Inventiou,

page_text: and the manner in which the same is to be performed, is particularly described
and ascertained in Drawings hereunto annexed, and to the following expla-
nation thereof, that is to say :-
My improvements in locomotive and other steam engines consist of an
apparatus for converting the reciprocating motion of the piston rod into a
continuous rotary motion.
In Sheet 1, Figure 1 is a plan view of the apparatus; Figure 2 a side
elevation; and Figure 3 a cross section. A is the piston rod; B, B, are racks
connected with the rod A by the cross head C; D, E, are spur wheels geering
with the racks B, B, and running loosely on the axes F and G. To the spur
wheels D, E, are attached ratchets or drivers H, I, taking into the ratchet
wheels J, K, fixed on the axes F and G. To the axis G is fixed a spur
wheel L taking into the intermediate M, in gear with the wheel N, fixed
on the axis F. As the piston moves from O to P, the wheel E, driven by the
rack B, B, drives the ratchet wheel K and axis G by the ratchet I. As
the piston moves from P to O the wheel D, driven by the racks B, B, drives
the ratchet wheel J and axis F by the ratchet H. From an inspection of the
Drawing it will be manifest that the motion of the wheel E and axis G, as the
piston moves from O to P, is in the same direction as the motion of the
wheel D and axis F, when the piston moves from P to O. This latter motion
is communicated to the axis G by the intermediate M, and thereby a conti-
nuous rotary motion is maintained in the axis G, driven alternately by the
ratchets H and I. To prevent the ratchets slipping on their wheels when
driven the contrary way to that in which they are respectively the drivers,
and to render their action more certain, I employ a contrivance, shewn in
detached parts in Figures 4, 5, 6, 7. The rachet I works loosely on a
pin a, fixed on the side of the wheel E. In the arm of the ratchet are
two lugs b, c. A friction slip d embracing the axis (or boss on the ratchet
wheel) has a projecting piece e passing between the lugs b, c. A pin f on the
As
wheel confines the action of the ratchet in the manner hereafter described.
The wheel E is loose on the axis to which the ratchet wheel K is fixed.
the wheel E revolves in one direction, the lug 6 is brought into contact with
the projecting piece e, causing the ratchet I to fall on the ratchet wheel K,
and drive it round. As the wheel E revolves in the opposite direction, the
lug C is brought into contact with the projecting projecting piece e, which
causes the ratchet I to rise from the wheel K till the lug c comes in contact
with the pin f, by the action of which the friction clip d is made to slip round
on the axis (or boss of the ratchet wheel), keeping the ratchet suspended.
I have not thought it necessary to give the plan of a stationary or marine

page_text: engine with the apparatus above described attached, the application being
sufficiently obvious.
In Sheet 2, Fig. 1 is a plan of a locomotive engine with my improvements
attached. Figure 2 is a longitudinal sectional elevation taken through the
dotted line a, b, in Figure 1. Figure 3 is a cross section of the same.
Figure 8 is a detached view of the cylinder bar and rollers. A is the
cylinder; B the piston rod, connected by a cross head C with the parallel
bar D; E is a groove in the frame of the carriage for the guide F of the
piston rod; G, H, are friction rollers composed of rings of leather firmly com-
pressed. The bar D passes between them, and the principal weight of the
engine being suspended on the axis of the upper roller, the bar and rollers are
in firm contact. When the bar D receives a rectilinear motion from the
piston rod, it produces a rotary motion of the rollers by friction of their
surfaces. The rollers run loose on their axes, which they drive alternately by
ratchets acting on ratchet wheels, in the same manner as the spur wheels
before described (see Sheet 1). The axis I of the roller G is the axis of the
driving wheels of the steam carriage. When the piston rod moves from J to K,
G is the driving roller, giving rotation to its own axis, and thereby an
advancing motion to the carriage. When the piston rod moves from K to J,
His the driving roller, giving rotation to its axis L in the same direction
as that given to the axis I by the roller G, when the piston rod moves from
J to K; the alternate motion thus given to the axis I and L being in the
same direction they may be connected together by a rod between cranks on
each, or by an intermediate friction roller working between two other rollers,
fixed thereon, or by a strap M and pullies N, whereby a continuous rotary
motion will be given to the axis I, and consequently a uniform advancing motion
to the carriage. If the weight of the carriage should not be found to give
sufficient friction to the driving rollers, I propose to employ pressure by steam
or other power acting on the axis of the upper roller. The amount of pressure
may be regulated by the engineer, and adapted to the circumstances of
the carriage in starting, or ascending inclined planes. I do not, however,
intend to limit myself in locomotive steam engines to the use of friction bars
and rollers, but propose, if advisable, to employ the rack and spur wheels
before described in locomotive as well as stationary or marine engine. The
valves of the locomotive engine are moved by a contrivance shewn in
Figures 1, 2. 0, 0, are bell crank levers connected together, and with the
lever P, by the bar Q. The levers O, O, and P, have their fulcra at
R, R, R, in the same straight line, and have a common communication with
the valve.rod S, by the lever T and bar U, Figure 1. On the levers O, O, are

page_text: friction rollers V, V, alternately acted upon by a double inclined plane W, on
the traction bar D. The reciprocating motion of the bar D is thus commu-
nicated to the valve rod S, and thereby regulates the action of the valves.
A represents a valve for shutting of the steam when using it expansively.
This valve may be worked from the opposite side of the inclined plane W, on
the bar D, by means of the rod m. The mode of reversing the motion of the
carriage is shewn in Figures 3, 4, 5, 6, and 7. Figure 4 is a longitudinal
section; Figures 5, 6, and 7, are detached parts of the apparatus. This
apparatus is a modification of that already described, Sheet 1, Figures 4, 5, 6, 7.
It consists of a double ratchet wheel, so called from its having a double set
of teeth, with a contrivance for working the ratchet against either part of
the wheel at pleasure, so as to obtain a forward or backward motion of the
carriage. G is the friction roller running loose on the axis, and carrying the
ratchet X on the pin n; Y is the double ratchet wheel fixed on the axis I ;
Z is the friction clip, embracing the axis (or a boss on the ratchet wheel), with
a projecting piece a passing between the lugs b, c, on the ratchet. When a
forward motion of the carriage is required, the action of the ratchet is con-
fined to the inner set of teeth d, d. When a backward motion is required, the
action of the ratchet is confined to the outer set of teeth e, e. The action of
the ratchet for a forward or backward motion of the carriage is governed in
the following manner: is a plate on the friction roller G, revolving there-
with, and slightly pressed thereto by screws passing through mortices g, g,
which allow it to slip in the manner hereafter described. In the plate f is a
groove h, i, penetrated by a pin j, fixed on the ratchet X, and passing through
a mortice K in the disc 6 of the friction roller G. When the pinj is in the
lower part of the groove h, i, the ratchet is free to fall on the inner set of
teeth d, d, or to rise from it, as the action of the roller G determines, but it is
prevented from rising to the outer set e, c. When the pin is in the upper
part of the groove h, i, the ratchet X has liberty to act or not on the outer
set e, e, as the action of the roller G determines, but cannot fall on the inner
set d, d. The position of the plate f, and thereby of the pin j, in the
groove h, i, is regulated by a brake at the pleasure of the engineer, who, by
throwing friction on the plate causes it to slip on the roller. The principal
advantage of the apparatus I have described for obtaining a continuous rotary
motion from the reciprocating action of the piston rod, is the opportunity
afforded to increase the length of the cylinder, and thereby of what is techni-
cally called the stroke of the engine. This applics more particularly to loco-
motive engines, the stroke of which has never, I believe, exceeded twenty
inches, whereas in the plan I have shewn, Sheet 2, Figure 1, the cylinder and

page_text: stroke are six feet long. Owing to the extra length of the cylinder the steam
may be worked expansively, so as to occasion a considerable economy of fuel,
and the wear and tear of the engine will likewise be diminished by the less
frequent action of the valves. In marine and stationary engines the position
of the cylinder may also be advantageously altered from the vertical to the
horizontal.
In the foregoing description and Drawings are included various parts of
locomotive and other steam engines already known and in use, to which my
improvements not applying, I make no claim. I claim the apparatus above
described for converting the reciprocating motion of the piston rod into a con-
tinuous rotary motion, and more particularly the following parts and combi-
nations, namely,-
First, the racks, spur wheels, and intermediate (Sheet 1, Figures 1, 2, 38).
Secondly, the mode of raising and depressing the ratchet or driver (Sheet 1,
Figures 4, 5, 6, 7).
Thirdly, the employment of friction bars and rollers to produce the change
of motion from rectilinear to rotary (Sheet 2, Figures 1, 2, 3).
And, lastly, the mode of reversing the rotary motion for a backward motion
of the steam carriage (Sheet 2, Figures 3, 4, 5, 6, 7).
In witness whereof, I, the said Joseph Whitworth, have hereunto set my
hand and seal, the First day of May, in the year of our Lord One
thousand eight hundred and thirty-eight.
JOSEPH (L.s.) WHITWORTH.
AND BE IT REMEMBERED, that on the First day of May, in the
first year of the reign of Her Majesty Queen Victoria, the said Joseph
Whitworth came before our said Lady the Queen in Her Chancery, and
acknowledged the Instrument aforesaid, and all and every thing therein con-
contained and specified, in form above written. And also the Instrument
aforesaid was stamped according to the tenor of the Statute made in the fifty-
fifth year of the reign of His late Majesty King George the Third.
Inrolled the Second day of May, One thousand eight hundred and thirty-