IMPROVEMENTS IN BARRING ENGINES OR ENGINES FOR TURNING LARGE ENGINES
Year: 1884

page_text: We, WILLIAM HARGREAVES and WILLIAM INGLIS of The Soho Iron Works,
Bolton, in the County of Lancaster, Engineers, do hereby declare the nature of
our said invention for "IMPROVEMENTS IN BARRING ENGINES OR ENGINES FOR
TURNING LARGE ENGINES" to be as follows:-
Our said Invention has for its object to construct and arrange the parts of
barring engines in an improved manner and so that the part which acts on the
large engine will be automatically moved out of gear from the large engine when-
ever the latter acquires a greater motion than what corresponds to the motion of
the barring engine. The improved engines forming the subject of our present
Invention are of the same class and designed for the same purposes as those
described in the Specification of Letters Patent granted to us and dated 9 August
1883 N° 3867.
'
In carrying out our present Invention a worm wheel is keyed on a line shaft or
other shaft turned by the large engine, and the barring engine is arranged to act
directly on this wormwheel by means of a worm or tangent screw instead of being
arranged as heretofore to act on the flywheel of the large engines. The worm is
made movable along the shaft carrying it, and is made to turn therewith by a
groove and feather or key. Whilst the barring engine is driving the large engine
the strain on the worm is in one direction and keeps the worm against a collar on
its shaft, but when the large engine gets into motion the wormwheel acts on the
worm like a pinion on a rack and presses the worm in the opposite direction.
The worm being free to move in the direction last referred to slides along the shaft
until it gets out of gear from the worm wheel. The improved barring engine in
its simplest form consists of a single steam cylinder and crank shaft carried by a
bracket-like frame which is by preference connected to the shaft of the large
engine by a part constructed like a bearing for the shaft, so that the engine is as it
were hinged or hung on the shaft. The worm is on the crank shaft; or in the
case of very large engines it may be on a shaft driven at a reduced speed from the
crank shaft. The shaft carrying the worm may be driven by any convenient
motor.
When the barring engine is required to be arranged so that the large engine or
shaft can be turned in either direction the part of the shaft on which the pinion

page_text: slides is made long enough for the pinion to move out of gear in either direction,
and a distance block is provided to be inserted at either side to hold the worm in
position whilst acting on the large engine.
Figure, 1, on the accompanying sheet of explanatory drawings is a transverse
vertical section showing an arrangement of our improved barring engine for acting
in one direction only this direction being indicated by an arrow.
the modified arrangement for acting in either direction.
Figure, 2, shows
A bracket-like frame, 3, hinged to the shaft, 4, of the large engine carries in
bearings, 5, 6, a crank shaft, 7, driven by a steam cylinder, 8,. fixed to the frame, 3,
A worm, 9, which is fitted to slide on the crank shaft, 7, being driven by means
of a groove and feather, gears with a worm wheel, 10, keyed on the shaft, 4,
When in action turning the worm wheel, 10, the worm, 9, bears against a collar, 11,
on its shaft, 7; but when the large engine moves of itself, the wormwheel, 10, moves
the worm, 9, along its shaft away from the collar, 11, and out of gear. The
worn, 9, must be pushed back again into gear when next required for acting on
or starting the large engine.
In the modification shown in figure, 2, space is provided for the worm, 9, to
slide in either direction out of gear from the wormwheel, 10, and a distance
block, 12, is placed between the worm, 9, and the bearing, 5, or between the
worm, 9, and the bearing, 6, accordingly as the shaft, 4, is to be turned in one
direction or the other. The engine or motor details must of course be arranged so
that the crank shaft, 7, can be driven in either direction as required.
Dated this seventh day of February 1884

page_text: We, WILLIAM HARGREAVES and WILLIAM INGLIS, of The Soho Iron Works, :
Bolton, in the County of Lancaster, Engineers, do hereby declare the nature of
our said invention for "IMPROVEMENTS IN BARRING ENGINES OR ENGINES FOR
TURNING LARGE. ENGINES" and in what manner the same is to be performed, to
be particularly described and ascertained in and by the following statement, that
is to say:-
Our said Invention has for its object to construct and arrange the parts of
barring engines in an improved manner, and so that the part which acts on the
large engine will be automatically moved out of gear from the large enginė
whenever the latter acquires a greater motion than what corresponds to the
motion of the barring engine. The improved engines forming the subject of our
present Invention are of the same class and designed for the same purposes as
those described in the Specification of Letters Patent granted to us and dated
9 August 1883, N° 3867.
In carrying out our present Invention a worm wheel is keyed on a line shaft or
other shaft turned by the large engine, and the barring engine is arranged to act
directly on this worm wheel by means of a worm or tangent screw instead of being
arranged as heretofore to act on the flywheel of the large engines. The worm is
made movable along the shaft carrying it, and is made to turn therewith by a
groove and feather or key. Whilst the barring engine is driving the large engine
the strain on the worm is in one direction and keeps the worm against a collar on
its shaft, but when the large engine gets into motion the worm wheel acts on the
worm like a pinion on a rack and presses the worm in the opposite direction. The
worm being free to move in the direction last referred to slides along the shaft
until it gets out of gear from the wormwheel. The improved barring engine in its
simplest form consists of a single steam cylinder and crank shaft carried by a
bracket-like frame which is by preference connected to the shaft of the large
engine by a part constructed like a bearing for the shaft, so that the engine is as it
were hinged or hung on the shaft. The worm is on the crank shaft; or in the case
of very large engines it may be on a shaft driven at a reduced speed from the
crank shaft. The shaft carrying the worm may be driven by any convenient
motor.
When the barring engine. is required to be arranged so that the large engine or
shaft can be turned in either direction, the part of the shaft on which the worm
slides is made long enough for the worm to move out of gear in either direction,
and a distance block is provided to be inserted at either side to hold the worm in
position whilst acting on the large engine.
Figure, 1, on the accompanying sheet of explanatory drawings is a transverse
vertical section showing an arrangement of our improved barring engine for acting
in one direction only this direction being indicated by an arrow. Figure, 2, shows
the modified arrangement for acting in either direction.
A bracket-like frame, 3, hinged to the shaft, 4, of the large engine carries in
bearings, 5, 6, a crank shaft, 7, driven by a steam cylinder, 8, fixed to the frame, 3.
A worm 9, which is fitted to slide on the crank shaft, 7, being driven by means of a
groove and feather, gears with a wormwheel, 10, keyed on the shaft, 4.
When in
action turning the worm wheel, 10, the worm, 9, bears against a collar, 11, on its
shaft, 7; but when the large engine moves of itself, the worm wheel, 10, moves the
worm, 9, along its shaft away from the collar, 11, and out of gear. The worm, 9,
must be pushed back again into gear when next required for acting on or starting
the large engine.

page_text: "In the modification shown in figure, 2, space is provided for the worm, 9, to slide
in either direction out of gear from the worm wheel, 10, and a distance block, 12, is
placed between the worm, 9, and the bearing, 5, or between the worm, 9, and the
bearing, 6, accordingly as the shaft, 4, is to be turned in one direction or the other.
The engine or motor details must of course be arranged so that the crank shaft, 7,
can be driven in either direction as required.
We do not restrict ourselves to the precise details herein described or delineated
provided that the distinctive feature of our 'Invention is retained this being the
employment of the worm arranged on the driving shaft so as to slide thereon out of
gear when the large engine gets into motion.
"
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.
:
Having now particularly described and ascertained the nature of our said
Invention and in what manner the same is to be performed we declare that what
we claim is:-
1
The employment in a barring, engine of a worm for acting on a wheel of the
large engine such worm being arranged to slide along its shaft out of gear when
the large engine gets into inotion substantially as hereinbefore described."
..
1.
Dated this fourteenth day of October 1884.
1.1
EDMUND HUNT,
Applicants' Agent.