AN IMPROVED BALANCE FOR HYDRAULIC LIFTS
Year: 1885

page_text: This Specification was, upon the 11th day of February 1887, amended under
Sections 18 to 21. of the Patents, Designs, and Trade Marks Act, 1883.
I GEORGE ANDREWS, of 14 Laurie Grove, New Cross, in the County of Surrey
Engineer do hereby declare the nature of my Invention for AN IMPROVED BALANCE
FOR HYDRAULIC LIFTS to be as follows:-
The object of my invention, is to construct balances for hydraulic lifts in an
improved manner, whereby I am enabled to dispense with the ordinary counter-
balance weights, chains, and top pullies.
In carrying out my invention, I effect the balance of the lift by means of
hydraulic pressure applied to a parallel piston, or to an annular piston fitted to or
forming part of such parallel piston in a cylinder; and sometimes, but not necessarily,
in combination with a load carried by the piston or pistons.
My invention mainly consists of a cylinder in a vertical or horizontal position
and preferably formed in two halves, and united together by bolts and nuts, one
upon or in line with the other. One half of the cylinder is bored, and the leathers
of the piston are fitted to slide, water tight, in this portion of the cylinder. When
weights are loaded above the piston, the bored portion of the cylinder is placed
upwards; and when such weights are carried below, the bored portion of the
cylinder is also below the unbored portion.
In carrying out my invention in connection with lifts using high pressures,
I place the stuffing box of the cylinder at the top, and the weighted load above the
plunger.
The plunger passes through the stuffing box, which is fitted with ordinary
hydraulic leathers. The plunger is in two lengths, screwed together, the lower
end being stopped or plugged. At the junction of the two parts the plunger
packing is fitted, of any suitable kind. The hore of the cylinder is just so much
larger than the diameter of the plunger, as is necessary to impart the necessary
pressure to the annular piston formed by the packing and its supports.
Water from the accumulator is admitted to the annular space by a suitable port
with a non-return valve. The lower part of the cylinder has a passage leading to
ihe lift cylinder, and the whole area of the plunger is exposed to the pressure
therefrom such area being usually made equal to that of the lift plunger.

page_text: When the lift is being lowered the balance plunger rises, the water from the lift
entering below. The water in the annular space is cut off from the accumulator
by the valve, and such water is ready for immediate use.
In applying my invention to low pressure lifts, I sometimes use a modified form
of that for high pressure, as before described; and in other cases I invert the
plunger, and arrange a water space in a portion of the plunger itself, into which
the water from the lift cylinder may enter, and thereby add to its weight, such
water space being provided with a separate plunger, in some cases, for the purpose
of providing an equal capacity to that of the lift.

page_text: GEORGE ANDREWS, of 14 Laurie Grove New Cross in the County of Surrey,
Engineer, do hereby declare the nature of my said invention and in what manner the
same is to be performed, to be particularly described and ascertained in and by the
following statement :-
The object of my invention is to construct balances for hydraulic lifts in an
improved manner whereby I am enabled to dispense with the ordinary counter-
balance weights, chains, and top pullies.
In carrying out my invention, I effect the balance of the lift by means of
hydraulic pressure applied to a parallel piston or to an annular piston forming part
of such parallel piston in a cylinder, and sometimes, but not necessarily in, combi-
nation with a load carried by the piston.
My invention consists of a cylinder in a vertical or horizontal position, and
preferably formed in two halves and united together by bolts and nuts, one upon
or in line with the other. One half of the cylinder is bored, and the leathers of
the piston are fitted to slide, water tight, in this portion of the cylinder. When
weights are loaded above the piston, the bored portion of the cylinder is placed
upwards; and when such weights are carried below, the bored portion of the
cylinder is also below the unbored portion.
In carrying out my invention in connection with lifts using high pressures,
I place the stuffing box of the cylinder at the top, and the weighted load above the
plunger-The plunger passes through the stuffing box, which is fitted with ordinary
hydraulic leathers. The plunger is in two lengths screwed together, at the junction
of the two parts the plunger packing is fitted, of any suitable kind. The bore of
the cylinder is just so much larger than the diameter of the plunger, as is necessary
to impart the necessary pressure to the annular piston formed by the packing and
its supporis.
Water from the accumulator is admitted to the annular space by a suitable port
in the starting valve. The lower part of the cylinder has a passage leading to the
lift cylinder, and the whole area of the plunger is exposed to the pressure there-
from; such area being usually made equal to that of the lift plunger.
When the lift is being lowered the balance plunger rises, the water from the lift
entering below. The water in the annular space is cut off from the accumulator
by the valve, and such water is ready for immediate use, and passes over to the
store tank.
In applying my invention to low pressure lifts, I sometimes use a modified form
of that for high pressure lifts. I invert the plunger and cylinder, so that the bored
portion of the cylinder is below, and the load weights are carried on the lower end
of the plunger. The lower portion of the cylinder has a pipe which connects it to
the lift cylinder, and is of equal capacity. When the lift is required to be raised, a
communication is opened between the tank, or water main, and the upper portion
of the balance cylinder.
And in order that my invention may be more particularly described and
ascertained, reference is hereby made to the accompanying drawings, in which
similar letters of reference indicate corresponding parts.

page_text: Fig. 1 is a sectional elevation of a hydraulic lift, constructed in accordance with
my invention, as arranged with the load m above the balance ram and cylinder;
Fig. 2 is a section of the ram and cylinder, on the line of Fig. 1. Fig. 3 is a
sectional elevation, shewing the invention arranged with the load ne placed below
the balance ram and cylinder; and Fig. 4 is a plan of the balance cylinder, as used
for low pressure lifts. is the cage, carried on the top of the ram b, which works
in the cylinder c. This cylinder is in communication with the lower portion of
the balance cylinder, by means of the pipe d. Another pipe leads from the upper
portion of the balance cylinder to the starting valve . The pipe is in com-
munication with the valve h and the accumulator or tank. is the parallel
plunger carrying the load m. kare the leathers fitted to the plunger n. 7 shews
the position of the hand line for actuating the starting valve 7, by a person in the
cage, or in other positions.
From the foregoing description the arrangement shown in Figs. 3 and 4 for low
pressure lifts will also be understood.
When the plunger bis raised, the water contained in the space is utilised by
passing through the pipe d to the cylinder the necessary surplus power being
obtained by opening the valve and thus admitting water from the accumulator to
pass up the pipe. y to the cylinder e surrounding the plunger » and pressing upon
the annular piston f.
When the plunger with the cage a are again lowered, the water from the
cylinder returns to the space under the plunger and the small quantity of
water contained in the cylinder e surrounding the piston is allowed to run away
by the valve h.
It will thus be seen that there is a great saving in the quantity of water required
to work lifts constructed as herein described as compared with ordinary lifts and
the ordinary balance weights are dispensed with.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
1. The manufacture and use of hydraulic lifts provided with hydraulic balance
appliances and arrangements for economising water substantially as herein before
described and shewn on the drawings.
2. The general construction and arrangement of the several and respective parts
and of the combination-of-come or all of them as shewn in fig. 1, that is to say, one
cylinder e and plunger n. n. with leathers K K and one stuffing box and fico cater
inlets & and g and balance weight in arranged to work as described in connerion with
a ram and cylinder and forming my invention of an improved balance for
hydraulic lifts substantially as herein before described and shewn on the drawings.
Dail 2 Al 1880
GEORGE DOWNING,
Agent for Applicant.