IMPROVEMENTS IN BARRING ENGINES OR ENGINES FOR TURNING LARGE ENGINES
Year: 1883

page_text: LETTERS PATENT to William Hargreaves, and William Inglis, both of Bolton,,
in the County of Lancaster. for an Invention of "IMPROVEMENTS IN BARRING
ENGINES OR ENGINES FOR TURNING LARGE ENGINES "
PROVISIONAL SPECIFICATION left by the said William Hargreaves and
William Inglis at the Office of the Commissioners of Patents on the
9th August 1883.
WILLIAM HARGREAVES and WILLIAM INGLIS, both of Bolton, in the County of
Lancaster "IMPROVEMENTS IN BARRING ENGINES OR ENGINES FOR TURNING
LARGE ENGINES
"
This Invention has for its object to construct and arrange the parts of barring
engines in an improved manner, and so that in each case, the part which acts on
the large engine will pass automatically out of gear from the large engine whenever
the latter acquires a greater motion than what corresponds to the motion of the
barring engine.
When factory and other steam engines are of large size it is sometimes necessary
to turn or move them by external means, either to get their parts into suitable
positions for being started or for other purposes; and for such purposes it is desirable
to provide what is known as a barring engine, which is a small engine arranged
to act on and turn the fly wheel of the large engine.
In carrying out the Invention the action of the barring engine is communicatod
by a pinion which when acting gears with teeth upon the flywheel of the largo
engine, and which pinion is keyed fast on a shaft driven, by preference through a
wormwheel and worm from a crank shaft acted on by two small cylinders. The
barring engine is arranged so that the entire engine or only a part carrying the
pinion driving shaft tends by gravitation or .otherwise to assume a position in
which the pinion is not in gear with the teeth of the flywheel; but when the
engine or part of it is moved to put the pinion into gear with the flywheel then it
will keep in that position so long as it is driving or acting on the flywheel. If
the large engine is being started then when its own motion becomes so great
[Price 8d 1

page_text: that the barring engine no longer drives it, the strain which kept the barring
engine in gear discontinues and the pinion at once moves out of gear from and
clear of the flywheel.
In one modification all the parts of the barring engine are carried upon a frame
which is fitted on journals or on a shaft so that it can have a rocking movement
and the parts are balanced so as to tend to hold the pinion out of gear; and when
the barring engine is required to act it is tilted or turned so as to put the pinion
into gear. The parts are arranged with reference to the direction of motion of the
flywheel so that the reaction or resistance to the action of the barring engine acts
on that engine in the direction for keeping it in gear. The barring engine may be
conveniently placed in a box frame inserted in a wall close to which the large
flywheel is placed as in many factory engines. The small cylinders of the barring
engine may be worked by steam or by water under pressure. The motive fluid
may be led to and from the cylinders through flexible tubing or through the
journals on which the engine is carried.
In other modifications the pinion shaft is carried by a frame arranged to rock or
turn concentrically with a pinion or with an internally toothed wheel which with
the worm wheel gearing, crank shaft and cylinders is on a stationary frame, and the
pinion shaft has fast on it a second pinion or wheel gearing like a sun-aud-planet
wheel with the pinion or with the internally toothed wheel of the stationary parts.
The directions of motion of the parts are arranged so that the driving strain
of the barring engine tends to keep the pinion in gear with the flywheel, but the
rocking frame is balanced so as to take the pinion out of gear, as soon as the
driving strain becomes neutralised by the proper motion of the flywheel.
Instead of directly driving a flywheel the barring engine may drive a wheel
fixed anywhere on the shaft of the large engine, or a wheel fixed on any other
suitable shaft connected to the crank shaft of the large engine.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Hargreaves and William Inglis in the Patent Office on
the 7th February 1884.
WILLIAM HARGREAVES and WILLIAM INGLIS, both of Bolton, in the County of
Lancaster. IMPROVEMENTS IN BARRING-ENGINES OR ENGINES FOR TURNING
66
LARGE ENGINES
"
Our said Invention has for its object to construct and arrange the parts of
barring engines in an improved manner and so that, in each case, the part which
acts on the large engine will pass automatically out of gear from the large engine
whenever the latter acquires a greater motion than what corresponds to the motion
of the barring engine.
When factory or other steam engines are of large size it is sometimes necessary
to turn or move them by external means either to get their parts into suitable
positions for being started or for other purposes; and for such purposes it is
desirable to provide what is known as a barring engine, which is a small engine
arranged to act on and turn the flywheel of the large engine.
In carrying out our Invention the action of the barring engine is communicated
by a pinion which when acting gears with teeth upon the flywheel of the large
engine, and which pinion is fast on a shaft driven, by preference, through a worm-
wheel and worm from a crank shaft acted on by two or more small cylinders.
The barring engine is arranged so that the entire engine or only a part carrying
the pinion driving shaft tends by gravitation or otherwise to assume a position in
which the pinion is not in gear with the teeth of the flywheel; but when the
engine or part of it is moved to put the pinion into gear with the flywheel then it
will keep in that position so long as it is driving or acting on the flywheel. If
the large engine is being started, then when its own motion becomes so great that
the barring engine no longer drives it, the strain which kept the barring engine in
gear discontinues, and the pinion at once moves out of gear from and clear of the
flywheel.
And in order that our said Invention and the manner of performing the same
may be properly understood we hereunto append threo sheets of explanatory
drawings to be hereinafter referred to and representing three modifications of
barring engines as made according to our Invention.
Figures 1 and 2, on sheet, 1, of the accompanying drawings are vertical and
horizontal sections of one modification of our improved barring engine, and figure, 3,
is an end elevation. Figure, 4, on sheet 2, is a vertical section of a second modifi-
cation; and figures 5, 6, and 7 on sheet, 3, are sectional views of a third modification.
In these drawings the same referenco numerals are used to mark the same or like
parts wherover they are repeated.
In the first modification, shown on sheet, 1, all the parts of the barring engine
are carried upon a frame, 11, of a box-like form, which is fitted on journals or on
a shaft, 12, so that it can have a rocking movement, the journals or shaft being
set in bearings, 13, on a bracket, 14, represented in figure 3 as fixed to a wall.
A part of the flywheel, 15, of the large engine to which the barring engine is
applied is shown in section in figures 1 and 2, being represented as made with
external grooves for rope driving, and as having a ring of internal shrouded
teeth, 16, formed on the inner side of its rim near one edge for the pinion, 17, of
the barring engine to gear into. The pinion, 17, turns loosely on a spindle, 18,
fixed across the frame, 11, and it is driven by a worm 19, the sides of its teeth
acted on by the worm being shaped like worm wheel teeth whilst the other sides. of

page_text: the teeth are shaped like spur teeth to act on the teeth, 16, of the large flywheel, 15.
The worm, 19, is fast on a shaft, 20, carried in bearings in the frame, 11, and this
shaft is formed with cranks, 21, on which are jointed the rams of three hydraulic
motor cylinders, 22. The rocking shaft, 12, of the frame, 11, is placed relatively
to the weight of the frame and the parts carried by it, so that the frame tends by
gravitation to turn into a position with the part at which the cylinders 22, are
placed, lower than as shown in figure, 1, and with the pinion, 17, moved sufficiently
over to be quite clear of the teeth, 16, of the large flywheel, 15. When the barring
engine is required to act the frame, 11, is placed in the position in which it is
-shown in figure, 1, with the pinion, 17, in gear with the teeth, 16, of the large
flywheel, 15; and then, the directions of motion being as indicated by the arrows
in figure, 1, when the barring engine is made to work, the reaction or resistance
to its action acts through the pinion, 17, on the frame, 11, in the direction to keep
the pinion in gear, the frame, 11, being prevented from moving downwards below
the proper position by abutments, 29, on the bracket, 14. When the large engine
gets into motion of itself to the extent to move the flywheel, 15, as fast as or fastor
than the barring engine tends to drive it, then the resistance to the driving action
of the barring engine being discontinued, gravitation takes effect on the frame, 11,
of the barring engine and turns it so as to take the pinion, 17, out of gear.
The crank shaft, 20, of the barring engine may be driven by cylinders worked
by steam or other motive fluid; and the motive fluid may be led to and from the
cylinders through flexible tubing or through the journals on which the engine is
carried.
In the second modification, shown in figure, 4, the axis of the crank shaft; 20,
and the axis on which the frame, 11, of the barring engine rocks are coincident;
and although a steam cylinder, 24, for driving the crank shaft, 20, is represented as
carried by the rocking frame, 11, it will be obvious that the one or more cylinders
for, driving the shaft may be fixed on a stationary frame or bracket. In this
second modification the worm, 19, which drives the pinion, 17, that gears with the
teeth, 16, of the large flywheel, 15, is not on the crank shaft, 20, but on an inter-
mediate shaft, 25, having fast on it a worm wheel, 26, driven by a worm, 27, on the
crank shaft, 20. In figure, 4, the parts are shown as arranged for turning the part
of the large flywheel, 15, with which the pinion, 17. gears, in the downward
direction, and the rocking frame, 11, and parts carried by it are so arranged as
regards weight or are so weighted as to tend to move the pinion, 17, downwards
and out of gear from the teeth, 16, of the large flywheel, 15, as soon as the driving
strain ceases to act. The teeth of the wheel, 17, are shaped on the sides acted on
by the worm like wormwheel teeth, whilst the other sides of the teeth are shaped
like spur teeth to act on the teeth, 16, of the flywheel, 15.
In the third modification shown in figures, 5, 6, and 7, a stationary frame, 28,
has fixed to it a pair of steam cylinders, 24, which drive a crank shaft, 20, having
on it a worm, 27. This worm, 27, gears with wormwheel teeth, 29, on the outside
of the rim of a wheel or disk, 30, having internal spur teeth, 31, on the inside of
its rim. Gearing with the internal spur teeth, 31, there is a pinion, 32, on one end
of a shaft, 33, having fast on its other end the pinion, 17, which gears with. the
teeth, 16, of the large flywheel, 15. The pinion shaft, 33, is carried by a drum or
rocking frame, 34, and this frame and the disk or wheel, 30, are carried on a
shaft, 35, fixed to the stationary frame, 28. The end of the shaft 33, on which the
pinion, 17, is fixed is carried by a projecting arm formed on the rocking frame, 34.
The rocking frame, 34, is weighted at the part, 36, opposite to the pinion shaft, 33,
so as to tend to raise the pinion, 17, into the position in which it is shown in
figure, 6, and indicated by dotted lines in figures, 5, and 7. In that position the
pinion, 17, is out of gear; and when the barring engine is about to be used for
starting the large engine the rocking frame, 34, is turned or moved by hand in any
convenient way to place the pinion, 17, in the position in which it is shown in full
lines in figure, 7, in gear with the teeth, 16, of the large flywheel, 15.
Instead of directly driving a flywheel the barring engine may be arranged to

page_text: drive a wheel fixed anywhere on the shaft of the large engine, or a wheel fixed on
any other suitable shaft connected to the crank shaft of the large engine.
Having thus particularly described our said Invention and the manner of
performing the same we have to state that we do not restrict ourselves to the
precise details herein described or delineated but that what we believe to be novel
and original and claim as the Invention secured to us by and in terms of the
herein before in part recited Letters Patent is :-
The arranging or combining together of the parts of barring engines or engines
for turning large engines substantially in the improved manner hereinbefore
described, the said improved barring engine acting on the large engine by means
of a pinion which with more or less of the other parts of the barring engine is
carried by a rocking frame weighted so as to move the pinion out of gear whenever
the pinion ceases to drive the large engine.
In Witness whereof, we, the said, William Hargreaves and William Inglis, have
-hereunto set our hands and seals this fifth day of February in the year of our
Lord One thousand eight hundred and eighty-four.
TE BARKUVAČ
HARGREAVES
15.
WILLIAM INGLIS, (L.S.)