Improvements in Hydraulic Motors.
Year: 1894

page_text: Improvements in Hydraulic Motors.
I, EUSTACE FITZMAURICE PIERS Baronet of 41 Finsbury Pavement in the
City of London, Mechanical Engineer do hereby declare the nature of this
invention to be as follows:-
An objection to hydraulic motors as hitherto constructed is that the stroke of the
piston or strokes of the pistons of the engine remains or remain the same whatever
may be the load on the motor and consequently waste of power results. The object
of my invention is to overcome this objection and this I effect by making the stroke
through which the piston or pistons of the motor works or work and consequently
the amount of water or liquid used to drive it or them variable with the amount of
work which is to be performed. This may be conveniently effected by making the
crank which the piston or pistons drive adjustable in length. This can be effected
for example by connecting the piston rod or piston rods of the motor cylinder to a
crank pin provided with a part which is movable in a slot in the crank disc or
crank cheeks and mounting the said part upon a screw capable of being rotated so
that by working this screw in one or the other direction the crank pin is moved
nearer to or further from the centre of the crank disc, thus lengthening or
shortening the stroke of the piston or pistons.
Dated this 18th day of September 1894.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, Agents.
Improvements in Hydraulic Motors.
1, EUSTACE FITZMAURICE PIERS Baronet of 41 Finsbury Pavement in the
City of London Mechanical Engineer do hereby declare the nature of my invention
and in what manner the same is to be performed to be particularly described and
ascertained in and by the following statement:-
An objection to hydraulic motors as hitherto constructed is that the stroke of the
piston or strokes of the pistons of the engine remains or remain the same whatever
may be the load on the motor and consequently waste of power results. The
object of my invention is to overcome this objection and this I effect by making
the stroke through which the piston or pistons of the motor works or work and
consequently the amount of water or liquid used to drive it or them variabie with
the amount of work which is to be performed. This may be conveniently effected
by making the crank which the piston drives or pistons drive adjustable in length.
This can be effected for example by connecting the piston rod or piston rods of the
motor cylinder or cylinders to a crank pin provided with a part which is moveable
in a slot in the crank disc or crank cheeks and mounting the said part upon a
screw capable of being rotated so that by working this screw in one or the other
direction the crank pin is moved nearer to or further from the centre of the crank
dise thus lengthening or shortening the stroke of the pistou or pistons.

page_text: Figures 1 and 2 represent in elevation at right angles to each other an arrange-
ment of mechanism for carrying out my invention but I do not restrict myself to
the arrangement shewn. A represents two hydraulic motors arranged to work in a
direction at right angles to each other the pistons of both motors being connected
by rods B to a block C capable of adjustment in a slot or opening D in a disc E
fast on the end of the shaft F.to be driven. The block C carries a nut or is
provided with a screwed hole in which works a screw G mounted in bearings
in the disc E so as to be capable of being turned but prevented from moving
longitudinally. By turning this screw in one direction or the other the block C
will be moved in the slot or opening D nearer to or further from the axis of the
disc according to the direction in which the screw is turned and so vary the strokes
of the pistons in the cylinders A and consequently vary the amount of liquid
admitted to the cylinders to drive the pistons. For example if the work to be done
requires the whole available power of the motors the block C should be moved in
the slot or opening D so far from the axis of disc E as to permit of the pistons
making their maximum length of stroke but if the whole power of the motors be
not required the block C should be moved towards the axis of the disc so as to
reduce the length of stroke of the pistons more or less according to the power
required. By this means it will be seen that a great economy in the use of liquid
for working the motors is effected as the amount of water used will be regulated
according to the amount of work to be done.
Having now particularly described and ascertained the nature of my inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In connection with hydraulic motors means whereby the stroke of the piston or
pistons and consequently the amount of liquid employed to drive it or them may
be varied as required according to the power required or work to be done
substantially as hereinbefore described.
2. Hydraulic motors having their pistons connected to a crank pin capable of
adjustment nearer to or further from the axis of rotation of the crank shaft so as to
vary the stroke of the pistons and consequently the amount of liquid for driving the
pistons substantially as hereinbefore described.
3. The combination with a hydraulic motor or bydraulic motors of a slotted disc
or its equivalent fast on the shaft to be driven by the said motors, a block
adjustable in position on the said disc or the like to which block the piston or
pistons of the motor or motors is or are connected and a screw working in a nut
or screw thread in the said block for the purpose of adjusting the block in position
nearer to or further from the axis of shaft to vary the stroke of the piston
or pistons as required substantially as and for the purpose berein before described
and illustrated by the accompanying drawings.
Dated this 18th day of June 1895.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.