IMPROVEMENTS IN THE CONSTRUCTION AND WORKING OF HYDRAULIC LIFTS, PARTS OF WHICH INVENTION ARE APPLICABLE TO OTHER SIMILAR APPARATUS FOR RAISING AND LOWERING LOADS "
Year: 1882

page_text: LETTERS PATENT to John Marsh Day, William Robert Green and Henry
Claude Walker, all of Falmouth Road, Great Dover Street, London in the
County of Surrey, Engineers, for an invention of "IMPROVEMENTS IN THE
CONSTRUCTION AND WORKING OF HYDRAULIC LIFTS, PARTS OF WHICH
INVENTION ARE APPLICABLE TO OTHER SIMILAR APPARATUS FOR RAISING
AND LOWERING LOADS
"
PROVISIONAL SPECIFICATION left by the said John Marsh Day, William
Robert Green, and Henry Claude Walker at the Office of the Commissioners
of Patents on the 27th May 1882.
JOHN MARSH DAY, WILLIAM ROBERT GREEN, and HENRY CLAUDE WALKER,
all of Falmouth Road, Great. Dover Street, London, in the County of Surrey,
Engineers, "IMPROVEMENTS IN THE CONSTRUCTION AND WORKING OF HYDRAULIC
LIFTS, PARTS OF WHICH INVENTION ARE APPLICABLE TO OTHER SIMILAR APPARATUS
FOR RAISING AND LOWERING LOADS
"
The first part of our Invention relates to an improved arrangement of apparatus
for raising or lowering loads, by means of Hydraulic pressure, whereby the use of
the ordinary balance chains and weights is entirely dispensed with.
For this purpose we propose to construct a moveable cylinder, the capacity of
which is such as to give the required power by the pressure of the water from the
tank or other available source necessary to raise the load and overcome the friction
caused by the working of the apparatus. This cylinder which may be made of.
any convenient proportion of the travel of the direct acting Ram is arranged to
slide up and down upon a fixed piston from the upper side of which projects a
trunk, whilst from the lower or under side descends a supply pipe leading from the
tank overhead. At the top of this pipe and immediately beneath the piston are
a number of perforations through which the water from the tank enters the
cylinder, the pressure pipe from the Ram being arranged to pass down through
the trunk and on to the upper side of the piston. In order to counterbalance the
weight of the Ram and Cage a number of weights are suspended from this.
cylinder.
'

page_text: By this arrangement no water is used for balancing the Ram and the respective
pressures due to the head of water in the two cylinders are maintained in the
required ratio during the entire travel of the Ram, the whole being thus equally
balanced at every part of the stroke.
This arrangement also provides for the water being used at the lowest level
whereby a great saving is effected, both in the working and cost of the whole
apparatus.
The second part of our Invention has reference to working the lift by means of
pumps the whole of the water under the accumulator piston being returned to the
high level tank at each stroke, the communication between them being always
open.
In applying our Invention to these we provide a suction tank with suitable
pumps to charge the accumulator with water at the requisite pressure and propose
to construct the Ram with a bucket or piston at its lower end, and to bore out its
cylinder to a corresponding size throughout its entire length; the diameters of the
ram and piston are so proportioned that the pressure on the area above the piston
is sufficient to overcome the load and friction. By so doing we are enabled to
make use of the pressure for the purpose of raising or lowering the load. The
under or larger area of the piston being so proportioned as to be capable of raising
the entire load, that is to say, the Cage, Ram, load and friction. This under or
larger area of the piston is always subjected to the pressure from the accumulator
whilst the apparatus is in use. In operation the action is as follows:-To raise the
Cage the starting valve which may be of ordinary construction is opened whereby
_communication being established between the upper portion of the ram, cylinder
and suction tank, the piston together with its load is caused to rise by the pressure
of the water upon its under surface. To lower the Cage, communication is
established by means of suitable pipes and valves from the accumulator to the
upper side of the piston whereupon owing to the additional thus brought to bear
upon it, the Ram and Cage are caused to descend.
The Third part of our Invention provides for using the above described lift as
a low pressure lift when the pumps are not working. To accomplish this a
suitable valve or valves are inserted in the pipe from the high level. cistern to the
accumulator by means of which the water can be caused to flow either from the
tank to the accumulator or from the accumulator to the discharge outlet.
In working, the Communication between the upper part of the cylinder of the
lift and the suction tank remains constantly open and the lift is worked from the
high level tank as in the first described arrangement.
Our Invention further provides for an automatic safety apparatus, consisting
essentially of a screw clip or collar to be actuated by a suitable governor. This
clip or collar through which the Ram passes may be secured immediately above
the Ram, the governors being driven direct from the Ram by frictional contact or
by means of a band or belt from the overhead gear. Should the speed of the Ram
be suddenly increased by accident or otherwise the speed of the governors would
also be increased which operating by means of a screw and lever upon the clip
or collar would cause the same to immediately grip the Ram and so arrest its
descent.

page_text: In carrying out the first part of our Invention we construct a moveable
cylinder A, the capacity of which is such as to give the required power by the
pressure of the water from the tank, or other available source, necessary to raise
the load and overcome the friction caused by the working of the apparatus. This
cylinder A, which may be made of any convenient proportion of the travel of the
direct acting ram I, is arranged to slide up and down upon a fixed piston B, from
the upper side of which projects a trunk C, whilst from the lower or under side
descends a supply pipe D leading from the tank overhead. At the top of this
pipe and immediately beneath the piston B are a number of perforations E,
through which the water from the tank enters the cylinder A, the pressure pipe G
from the ram I being arranged to pass down through the trunk C and on to the
upper side of the piston B. In order to counterbalance the weight of the ram I
and cage L, a number of weights F are suspended from this cylinder A.
By this arrangement no water is used for balancing the ram and the respective
pressures due to the head of water in the two cylinders A and H are maintained
in the required ratio during the entire travel of the ram; the whole being thus
equally balanced at every part of the stroke.
This arrangement also provides for the water being used at the lowest level,
whereby a great saving is effected, both in the working and cost of the whole
apparatus.
To carry out the second part of our invention we provide (see Figs 1 and 2
Sheets I and II) a suction tank N with suitable pumps to charge the accumulator
with water at the requisite pressure, and also construct the ram I with a bucket or
piston K at its lower end, and bore out its cylinder H to a corresponding size
throughout its entire length; the diameters of the ram and piston are so pro-
portioned that the pressure on the area above the piston is sufficient to overcome
the load and friction. By so doing we are enabled to make use of the pressure for
the purpose of raising or lowering the load. The under or larger area of the
piston being so proportioned as to be capable of raising the entire load, that is to
say the cage, ram, load and frictional resistance. This under or larger area of the
piston is always subjected to the pressure from the accumulator whilst the
apparatus is in use.
To raise the cage L, the starting valve M (which may be of ordinary construction)
is opened, whereby communication being established between the upper portion of
the ram cylinder H and suction tank N, the piston K, together with its load, is
caused to rise by the pressure of the water upon its under surface.
To lower the cage L, communication is established, by means of the pipe G and
valve M, from the accumulator to the upper side of the piston K, whereupon, owing
to the additional load thus brought to bear upon it, the ram I and cage L are
caused to descend.
The means by which we accomplish the third part of our Invention are shown
Fig: 4 Sheet II, where it will be seen that a valve M is inserted in the pipe D
from the high level cistern to the accumulator, by means of which the water can
be caused to flow either from the tank to the accumulator, or from the accumulator
to the discharge outlet Q In working, the communication between the upper
part of the cylinder H of the lift and the suction tank N remains constantly open
and the lift is worked from the high level tank as in the first described
arrangement.
Our improved automatic safety apparatus is shown Figure 6 Sheet I of the
Drawings, where it will be seen that the ram I passes through the clip or collar R,
the governors S being driven direct from the ram I by the friction roller T, or by
means of a band or belt from the overhead gear. Should the speed of the ram be
suddenly increased, by accident or otherwise the speed of the governers would also
be increased, which operating by means of the screw U and lever V upon the clip
or collar R would cause the same to immediately grip the ram and so arrest its
descent.

page_text: Having now described and ascertained the Nature of our said Invention and in
what manner the same is or may be performed
We Claim as secured to us by the hereinbefore in part recited Letters Patent :-
Firstly. In a hydraulic lift, causing the water from the supply tank, or available
source, to enter immediately below the piston or ram of the accumulator or
balancing cylinder, substantially as hereinbefore described and shown Figs 1 to 4
of the accompanying Drawings; whereby we obtain the use of the pressure of the
water at the lowest possible point.
Secondly. The application of our Invention to the working of an ordinary
multiplying cylinder whereby the use of balance weights and chains is entirely
dispensed with as shewn Fig: 5 of the Drawings.
Thirdly. The construction of the apparatus for controlling the descent of the ram
and cage substantially as described and as shown in Fig: 6 of the Drawings.
In Witness whereof I the said Henry Claude Walker for myself and on
behalf of my Co-patentees have hereunto set my hand and seal this Twenty
fifth day of November in the year of Our Lord One thousand Eight
hundred and Eighty two,
HENRY CLAUDE WALKER (L.S.)