Year: 1888

page_text: Date of Application, 6th Jan., 1888
Complete Specification .Left, 2nd Oct., 1889
Complete Specification Accepted, 9th Nov., 1888
I, WILLIAM ROBERT GREEN of the Newington Iron Works Falmouth Road
London S.E. Engineer do hereby declare the nature of this invention to be as
follows:-
My invention relates to improvements in the "balance accumulators" of hydraulic
direct-acting lifts and has for its object the working of the lift, balanced, with either
high or low-pressure water.
In the "balance accumulators" as ordinarily constructed for working with low
pressure water the lifting ram of the lift is operated by water taken from a vertical
cylinder with ram, which I here.term the balancing cylinder, weighted so as to nearly
balance the cage. The water in this balancing cylinder is forced out or allowed to
return by the movement of a larger ram operated with low pressure water taken from
the street main or other convenient source, the ingress and egress of this low pressure
water being controlled by suitable valves. This arrangement is suitable only for the
one pressure at which it was designed to work and should it at any future time as
frequently happens be advisable to operate it with high pressure water considerable
alterations are required such as the substitution of a new cylinder and ram entailing
stoppage of the lift and causing in many cases great inconvenience.
In the balance accumulator" of my invention I retain the balancing cylinder as
before but connect it to two rams of different areas instead of the one. The large ram
is designed of suitable area to work at the desired low pressure and the small ram
designed for a pressure of say 700 lbs. per sq. in. such pressure being a usual one for
high pressure hydraulic machinery. Suitable valves are provided to control the
ingress and egress of water to either of these cylinders at will so that a
"balance
accumulator of my invention can be constructed to operate a lift with any one
desired pressure and also be available for working with ordinary high pressure
without any alterations thus obviating loss of time or further expense.
::
In the foregoing description I have for the sake of clearness described my invention
as consisting principally of three rams namely a balancing ram and two rams of

page_text: different areas for operating the same but in some forms of my invention I use
pistons instead of rams or make any or all of the three rams or pistons aforementioned
in duplicate or in some cases instead of fixing the cylinders and allowing the rams or
pistons to move I may fix any of the rams or pistons and allow the cylinders to move
and by this means economise space by causing a large ram to act as the cylinder for a
smaller ram.
In cases where it is not convenient to arrange the cylinders vertically
I may place them horizontally or at an angle.
1 L
J, WILLIAM ROBERT GREEN of the Newington Iron Works, Falmouth Road,
London S.E. Engineer, 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 :-
My invention relates to improvements in the "balance accumulators" of hydraulic
direct-acting lifts and has for its object the working of the lift, balanced, with either
high or low pressure water.
23
In the "balance accumulators as ordinarily constructed for working with low
pressure water the lifting ram of the lift is operated by water taken from a vertical
cylinder with ram, which here term the "balancing cylinder," weighted so as to
nearly balance the cage. The water in this balancing cylinder is forced out or allowed
to return by the movement of a larger ram operated with low pressure water taken
from the street main or other convenient source the ingress and egress of the low
pressure water being controlled by suitable valves. This arrangement of "balance
accumulator "
is suitable only for the one pressure at which it was designed to work
and should it at any future time, as frequently happens, be advisable to operate it with
high pressure water considerable alterations are required such as the substitution of a
new ram and cylinder entailing stoppage of the lift and causing in many cases great
inconvenience.
In the "balance accumulator" of my invention I retain the balancing cylinder as
before but connect it to two rams of different areas instead of the one. The large
ram is designed of suitable area to work at the desired low pressure and the small
ram designed for a pressure of say 700 pounds per square inch such pressure being a
usual one for high pressure hydraulic machinery. Suitable valves are provided to
control the ingress and egress of water to either of these cylinders at will so that a

page_text: "balance accumulator" of my invention can he constructed to operate a lift with any
one desired pressure and also be available for working with ordinary high pressure
without any alterations thus obviating loss of time or further expense.
In the accompanying drawings the same letters indicate the same or corresponding
parts and the different views show various forms of my Invention.
Fig. 1 shows the form in which I preferably construct the "halance accumulator "
of my invention. In this view I have shown my invention fitted with a controlling
valve and also a change valve by means of which the apparatus can be operated with
high or low pressure water at will, But in cases where it is intended to work the lift
entirely with low pressure water until the change is made, and then made permanently,
to high pressure I do not use a change valve but employ only a low pressure controlling
valve until the conversion and then substitute a high pressure one.
Fig. 2 shows an alternative plan of constructing my Invention.
In this form I
arrange the high and low pressure cylinders in tandem fashion instead of one within
the other.
Fig. 3 shows another alternative plan of constructing my Invention. In this form I
use pistons instead of rams.
A is the lifting cylinder of an ordinary direct-acting hydraulic lift with lifting ram a
and cage a
b¹
B is the "balancing cylinder" with ram 6 and pipe 6' connecting it to the lifting
cylinder. In fig. 1 this cylinder also forms the low pressure ram c.
is the low pressure cylinder with rame and pipe e¹ communicating with the
controlling apparatus.
Dis the foundation plate with standards & supporting the low pressure cylinder and
its connections. The balancing ram is fixed at to this foundation plate which is
also provided with stop pieces d² which come into contact with balance weights E
when in their lowest position.
E are the balance weights resting on a flange e formed around the bottom of
balancing cylinder B.
F is a crosshead secured to the low pressure cylinder with bolts and carrying the
high pressure ram g. The upper portion of low pressure cylinder is made
removeable to enable the gland of high pressure cylinder to be easily examined and
is fitted with water-tight joints and secured by crosshead F.
Gis the high pressure cylinder with ram g. The upper part 3 of this cylinder
forms the cover of lifting ram e. g is the pipe communicating with the controlling
mechanism.
H is a controlling valve of ordinary construction operated by hand ropes h. The
pressure water is admitted by pipe and stop valves. The exhaust pipe h³ empties
into tank J.
I is the change valve with operating handle i and pipe communicating with tank .J
below the water line. This change valve is so constructed that the pressure water can
be admitted either to the high or low pressure cylinder at will and that whilst one of
the cylinders is in communication with the controlling valve the other is in communi-
cation with tank J and is thereby kept full of water and any undue vacuum
prevented.
The action of the apparatus shown in fig. 1 is as follows:-
The balancing cylinder has an effective capacity quite equal to the lifting cylinder
and is assumed to be at the top of its stroke. The balance weights E are adjusted so
that together with the weight of balancing cylinder and high pressure cylinder they
almost equal the weight of lifting ram and empty cage, only leaving a preponderance
sufficient to cause the cage to descend at the requisite velocity. To lift the load
pressure water is admitted to either high or low pressure cylinder and so forces the
water out of balancing cylinder into lifting cylinder. To lower the load the water is
allowed to flow out of high and low pressure cylinders and the weight of load together
with preponderance of cage forces the water back into the balancing cylinder and
by lifting the balance weights with their connections forces the water out of high and
low pressure cylinders.
::

page_text: In the foregoing description I have for the sake of clearness described my invention
as consisting principally of three rams, namely, a balancing ram and two other
rams of different areas for operating the same but in some forms of my invention [
use pistons instead of rams or make any or all of the three rams or pistons afore-
mentioned in duplicate.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I wish it to be
particularly understood that I do not bind myself to the exact details shown and
described nor do I confine myself to the arrangement of valves shown for operating
the same but I do declare that what I claim is :-
1. In "balance accumulators" for hydraulic lifts, the employment of three or
more rams or pistons or their equivalent by means of which the lift can be operated
with either high or low pressure water.
2. The combination, construction, and arrangement of "balance accumulator "
*substantially as shewn in fig. 1.
3. The combination, construction, and arrangement of "balance accumulator "
substantially as shown in fig. 2.
4. The combination, construction, and arrangement of "balance accumulator ”
substantially as shewn in fig. 3.
Dated this .29th.day of September 1888.
WILLIAM ROBERT GREEN.