Year: 1887

page_text: We, WILLIAM ROBERT GREEN and ROBERT CAREY both of the Newington Iron
Works Falmouth Road London S.E. Engineers do hereby declare the nature of this
invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement:-
Our invention relates to improvements in hydraulic cranes and lifts and has for its
object to enable a crane or lift designed to work with high pressure water to be
worked at will with low pressure water.
In most cases the only pressure of water available for working hydraulic machinery
is that of the ordinary service mains unless engines and pumps are provided to supply
water at high pressure. To provide engines and pumps for working one or two
machines means considerable outlay in first cost and expense in attendance and
maintainance. Our invention is for the purpose of economically supplying high
pressure water to cranes or lifts without using the ordinary engines and pumps the
motive power being low pressure water taken from the ordinary service water mains
or from tanks, and at the same time to enable high pressure water to be used, should
it at any time be available without altering the cylinder of crane or lift.
In the accompanying drawing we shew one form of our invention as applied to the
cylinder of a crane or lift in such a manner that either high or low pressure water can
be used to operate it.
A is the cylinder of crane or lift designed to work with high pressure water. B is
the "intensifier" of ordinary construction with fixed cylinder b within which works
the large ram b forming the cylinder for the fixed small ram 62. C is the controlling
valve operated in the usual manner by hand rope c. D. E. F. G. H are stop cocks
and d. e. f. the connecting pipes.
When it is desired to lift the load with the low pressure water the cock D is closed
and cock E opened admitting the low pressure water to the controlling valve C. The
cock G is closed and F and H opened so that when the pressure water is admitted
into pipe d it enters cylinder band presses upwards the ram b' causing the water
displaced by ram 2 to pass along pipes and e into cylinder A and so lifting the load.
By this arrangement the pressure of water available in lifting cylinder will be

page_text: greater than the pressure in cylinder & in the proportion that the area of ram b¹ bears
to that of ram 62, and the sizes of rams are so proportioned that the required pressure
may be reached in cylinder A. To lower the load the water is allowed to pass out of
cylinder and the ram b' will therefore descend allowing the water to flow out of
cylinder A and so lowering the load.
When the high pressure water is used the cock E is closed and D opened admitting
the high pressure water to valve C. The cocks F and H are closed shutting off the
intensifier B and cock G opened thus putting cylinder A in direct communication with
valve C by which it is worked in the usual manner.
In cases where it is considered desirable or expedient to work the crane or lift for a
period exclusively with low pressure and then alter it to high pressure the stop cocks
shewn on the accompanying drawing are omitted and valve C supplied with low
pressure water and connected solely to cylinder b, cylinder A being connected solely
by pipes e and fand operated entirely by the intensifier until the change is made to
high pressure. We then connect valve to cylinder A by a new pipe and substitute
the high pressure supply pipe to valve (for the low pressure one and do away with
the intensifier.
In some cases instead of employing rams for setting up the power in the intensifier
we employ pistons or other appliances for producing the same result.
Having now particularly described and ascertained the nature of our invention and
in what manner the same is to be performed we wish it to be particularly understood
that we do not bind ourselves to the exact details hereintofore described and illustrated
nor do we claim the particular construction of "intensifier" but we do declare that
what we claim is :-
:―
The application of an "intensifier," substantially as shewn and described, to
hydraulic cranes and lifts so that the cylinders of said cranes and lifts can be
supplied with high pressure water without the use of engines and pumps the motive
power being derived from low pressure water taken from tanks or from the ordinary
service mains.