Improvements in Hydraulic Lifts.
Year: 1891

page_text: Date of Application, 22nd Oct., 1891
Complete Specification Left, 18th July, 1892-Accepted, 3rd Sept., 1892
PROVISIONAL SPECIFICATION.
Improvements in Hydraulic Lifts.
I WILLIAM CARTER of No. 32 King Street in the City of Chester Mechanical
Engineer do hereby declare the nature of this invention to be as follows:-
My invention consists of a direct acting hydraulic lift and hydraulic balance
combined, the parts of the said hydraulic lift and balance being constructed,
arranged and acting substantially as hereinafter described.
In constructing a combined direct acting hydraulic lift and balance according to
my invention I use an ordinary differential accumulator consisting of a vertical
fixed tubular or hollow ram having two diameters, the lower portion being of larger
diameter than the upper portion. On this fixed hollow ram, a weighted or balance
cylinder slides, the said cylinder having stuffing boxes at top and bottom corre-
sponding with the two diameters of the fixed ram. Arranged axially in the hollow
fixed ram is the movable ram of the direct acting hydraulic lift to be balanced.
The hollow fixed ram described forms part of the lift cylinder, the remaining part
of the lift cylinder being attached to the lower end of the said hollow fixed ram.
Where the smaller diameter of the hollow fixed ram sets in, one or more holes are
made for forming a communication between the lift cylinder described and the
concentrically arranged balance or moving cylinder. By adjusting the size of the
hole or holes the required speed for working the lift may be obtained. The water
in the lift cylinder and the moving or balance cylinder is an enclosed or fixed
quantity and the said water circulates between the two cylinders as the litt ascends
and descends, the water passing from one to the other cylinder through the hole or
holes hereinbefore mentioned. On the moving or balance cylinder being forced
downwards in the manner hereinafter described, the lift ascends, the reverse motion
of the lift taking place when the moving cylinder rises on the fixed ram.
The moving or balance cylinder is so loaded as to partially balance, or, if
necessary, overbalance the dead weight of the lift ram and the cage or platform
carried by it.
The moving or balance cylinder may be actuated by any of the several arrange-
ments of parts hereinafter described.
According to one of the said arrangements 1 use one or more small tubular rams
arranged concentrically (when more than one is used) about the fixed axial ram or
lift cylinder and carried by a cross head secured to the upper end of the fixed axial
ram or lift cylinder. The small tubular rams carried by the cross head described
are inserted in cylinders carried by and arranged around the exterior of the
balance or sliding cylinder. When pressure water is admitted to the small tubular
rams described the moving or balance cylinder is forced down and when the said
water is exhausted the moving or balance cylinder ascends.
In this arrangement the lift ram and cage or platform are only partially
balanced.
According to another arrangement in place of using a single acting ram or rams
as last described, one or more cylinders, fixed to the balance or sliding cylinder,
having pistons in them may be used, the said pistons and their piston rods being
fixed to the cross head and so constructed that both an upward and downward
pressure may be exerted on the moving or balance cylinder by the said pistons. By
this arrangement greater economy of working is obtained.
In this arrangement and that next described the lift ram and cage are over-.
balanced to the extent of about half the maximum load, so that with an average
load in the cage the whole mechanism is in equilibrium and no power is required

page_text: to cause the load to either ascend or descend beyond that necessary to overcome
the friction of the parts.
Motion may be imparted to the moving or balance cylinder by means of rotary
motion derived from a prime mover in the following manner. To the sides of the
moving cylinder one or more vertical racks is or are attached with which rotary
pinions gear so as to give the required reciprocating motion to the moving cylinder.
The rotary pinions gearing with the racks are driven by toothed or other gearing
from a horizontal shaft the motion of which is made capable of ready reversal.
Instead of the racks and pinions and gearing described vertical screws working
in screw boxes or screw nuts may be employed to give the reciprocating motion to
the sliding. or balance cylinder.
It is preferred to load the sliding or balance cylinder with cast iron or other
weights but the same effect may be produced when water under pressure is available
by using additional single acting rams and cylinders, the latter being fixed to the
moving cylinder and the said additional single acting rams being placed in constant
communication with the pressure water.
Dated the 22nd day of October 1891.
W. T. WHITEMAN,
Agent for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Hydraulic Lifts.
I, WILLIAM CARTER, of No. 32 King Street in the City of Chester, 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:-
My invention consists of a direct acting hydraulic lift and hydraulic balance
combined, the parts of the said hydraulic lift and balance being constructed,
arranged and acting substantially as hereinafter described.
In constructing a combined direct acting hydraulic lift and balance according to
my invention, I use an ordinary differential accumulator consisting of a vertical
fixed tubular or hollow ram having two diameters the lower portion being of larger
diameter than the upper portion. On this fixed hollow ram a weighted or balance
cylinder slides the said cylinder having stuffing boxes at top and bottom corre
sponding with the two diameters of the fixed ram. Arranged axially in the hollow
fixed ram is the movable ram of the direct acting hydraulic lift to be balanced.
The hollow fixed ram described forms part of the lift cylinder the remaining part
of the lift cylinder being attached to the lower end of the said hollow fixed ram.
Where the smaller diameter of the hollow fixed ram sets in, one or more holes are
made for forming a communication between the lift cylinder described and the con-
centrically arranged balance or moving cylinder. By adjusting the size of the hole
or holes the required speed for working the lift may be obtained. The water in
the lift cylinder and the moving or balance cylinder is an enclosed or fixed quantity
and the said water circulates between the two cylinders as the lift ascends and
descends, the water passing from one to the other cylinder through the hole or
holes hereinbefore mentioned. On the moving or balance cylinder being forced
downwards in the manner hereinafter described, the lift ascends the reverse motion
of the lift taking place when the moving cylinder rises on the fixed ram.
The moving or balance cylinder is so loaded as to partially balance or balance
or, if necessary, overbalance, the dead weight of the lift ram and the cage or
platform carried by it.
The moving or balance cylinder may be actuated by any of the several arrange-
ments of parts hereinafter described.
According to one of the said arrangements I use one or more small tubular rams
arranged concentrically (when more than one is used) about the fixed axial ram or

page_text: lift cylinder and carried by a cross head secured to the upper end of the fixed axial
ram or lift cylinder. The small tubular rams carried by the cross head described
are inserted in cylinders carried by and arranged around the exterior of the balance
sliding cylinder. When pressure water is admitted to the small tubular rams
described the moving or balance cylinder is forced down and when the said water is
exhausted the moving or balance cylinder ascends.
or
In this arrangement the lift ram and cage or platform are only partially
balanced.
According to another arrangement in place of using a single acting ram or rams
as last described one or more cylinders fixed to the balance or sliding cylinder,
having pistons in them may be used, the said pistons and their piston rods being
fixed to the cross head and so constructed that both an upward and downward
pressure may be exerted on the moving or balance cylinder by the said pistons.
By this arrangement greater economy of working is obtained.
In this arrangement and that next described the lift ram and cage are over-
balanced to the extent of about half the maximum load, so that with an average
load in the cage the whole mechanism is in equilibrium and no power is required to
cause the load to either ascend or descend beyond that necessary to overcome the
friction of the parts.
Motion may be imparted to the moving or balance cylinder by means of rotary
motion derived from a prime mover in the following manner. To the sides of the
moving cylinder one or more vertical racks is or are attached with which rotary
pinions gear so as to give the required reciprocating motion to the moving cylinder.
The rotary pinions gearing with the racks are driven by toothed or other gearing
from a horizontal shaft the motion of which is made capable of ready reversal.
Instead of the racks and pinions and gearing described, vertical screws working
in screw boxes or screw nuts may be employed to give the reciprocating motion to
the sliding or balance cylinder.
It is preferred to load the sliding or balance cylinder with cast iron or other
weights but the same effect may be produced when water under pressure is available
by using additional single acting rams and cylinders the latter being fixed to the
moving cylinder and the said additional single acting rams being placed in constant
communication with the pressure water.
I will now describe with reference to the accompanying drawing the manner in
which my invention is to be performed.
Figure 1 represents in vertical section a combined direct acting hydraulic lift
and balance constructed according to my invention the balance cylinder being
loaded so as to partially balance the lift ram and its cage or platform. The said
Figure 1 also exhibits one of the arrangements which may be used for actuating
the moving or balance cylinder and consequently the movable ram of the lift.
Figure 2 represents an elevation of the combined hydraulic lift and balance
represented in Figure 1 but the moving or balance cylinder in this arrangement is
actuated by rotary motion derived from a prime mover as hereinafter particularly
explained.
Figure 3 represents in section and Figure 4 a portion of the same also in section,
drawn to a larger scale, the arrangement in which the moving or balance cylinder
is actuated by means of a double acting piston and rod.
:
I will first describe the arrangement represented in Figure 1. a, a² is the fixed
hollow ram of the differential accumulator or balance having two diameters as
represented, the lower portion a' being of larger diameter than the upper portion a.
To the bottom of the larger portion a² of the fixed hollow ram a a², a cylinder c is
fixed a portion only of which is represented. The said cylinder c is closed at
its bottom end and has a length sufficient to accommodate the range of motion of
the lift.
The fixed hollow ram a, a² and the cylinder c at its bottom form one continuous
chamber for holding the water by which the direct acting movable ram b of the
lift is balanced and worked, the said ram b being situated and working axially in

page_text: :
the said fixed ram a a² and ram cylinder c as represented. The direct acting
movable ram b carries at its top the platform or cage f; d is the balance or moving
cylinder weighted as represented, the said cylinder d being concentric with and
capable of rising and falling upon the fixed hollow or tubular ram a, a² the said
moving or balance cylinder d being furnished at top with the stuffing box d' working
upon the reduced part a of the fixed hollow ram and at bottom with the stuffing
At the
box d working upon the larger diameter a of the fixed hollow ram.
shoulder between the smaller part, a and the larger part a² of the fixed hollow
ram a, a³ one or more holes or apertures at e is or are made. By means of the
aperture or apertures at e a communication is established between the balance or
sliding cylinder d and the lift cylinder c in which the lower part of the movable
ram b works through the hollow fixed ram a a². In the balance cylinder d, hollow
ram a, a' and lift cylinder c a fixed or enclosed quantity of water is contained, the
said water circulating through the hole or holes ate as the lift ascends and descends ;
that is to say, as the balance cylinder d is forced down or made to descend upon
the fixed hollow ram a a' the water in it is forced through the hole or holes at e
into the said hollow ram a, a and cylinder c which water under pressure acting
upon the bottom of the movable ram b in the lift cylinder c raises the said ram b
and the load on the platform or in the cage f. When the balance cylinder d rises
the water is returned to it from the lift cylinder c and fixed hollow ram a a² and
the lift ram 6 may descend in its cylinder. By adjusting the size of the hole or
holes at e the desired speed of working the lift may be obtained.
The bottom of the moving or balance cylinder d is provided with a flange or
platform don which weights g are placed for the purpose of partially balancing or
if necessary over-balancing through the water in the said cylinder d, hollow fixed
ram a, a² and ram cylinder c, the dead weight of the lift ram b and the cage or
platform carried by it.
I will now describe the arrangement represented in Figure 1 for actuating the
moving or balance cylinder d and the lift combined with it. Arranged around and
carried by the said moving or balance cylinder d is a series of three or more
cylinders, in which the fixed tubular rams i, i are inserted, the rams i, i being
carried by the cross head k secured to the upper or smaller part a of the fixed
hollow ram a a². These hollow rams i in the cylinders h, are in communication
A single
either with water under pressure or with the exhaust by the pipe l.
cylinder or ram 1, i may be used in place of the series represented in the
drawing.
When pressure water is admitted to the tubular rams i through the pipe / the
balance cylinder d is forced down and the lift operated in the manner hereinbefore
described; and when the said water is exhausted from the tubular rams i the said
balance cylinder is permitted to ascend by the return of the water from the lift
cylinder c as before explained.
In place of the single acting actuating ram or rams i represented in Figure 1
double acting pistons and rods of the kind represented in Figure 3 and a portion
represented, drawn to a larger scale, in Figure 4 may be employed for giving both
an upward and downward motion to the balance cylinder d. In this case, one or
more cylinders, closed at top and bottom, is or are carried by the balance
cylinder d, but in place of a fixed hollow ram, a fixed rod m having at its bottom a
piston n is employed. These rods and their pistons m, n are carried by the cross
head k. In the rod m and passing through the piston n is a water passage m³
opening on the underside of the said piston n and in the rod m is a second water
passage m opening on the upper side of the piston n. These passages can either
be put into communication with the pressure water or the pressure water be
exhausted from them. When the passage m³ is open to the pressure water and the
passage m³ to the exhaust, the balance cylinder d is forced down by the pressure
water acting on the bottom of the cylinder (or cylinders); and when the passage
is open to the water pressure and the passage m³ to the exhaust, the pressure water
is admitted to the upper side of the piston and acting on the top of the cylinder h
m®

page_text: lifts the balance cylinder d. In this arrangement the lift ram 6 and the cage fare
overbalanced by the weights g to the extent of about half the maximum load so
that with an average load in the cage f the whole mechanism is in equilibrium and
no pressure is required to cause the load to either ascend or descend beyond that
necessary to overcome the friction of the parts and the resistance due to the
displacement of the water by the ram b.
I will now describe the arrangement represented in Figure 2 which may be used
for giving motion to the moving or balance cylinder d by means of rotary motion
derived from a prime mover: p, p are vertical toothed racks attached to the sides
of the moving or balance cylinder d. With these vertical racks, pinions q, q gear
the said pinions q, q being driven from the horizontal shaft r, which is capable of
ready reversal through the worms 8, s on the shaft gearing with the worm
wheels t, t on the shafts of the pinions 9, q. When the shaft is driven in one
direction the pinions 9, 9 give a descending motion to the racks p, p and through
them to the balance cylinder d; and when the motion of the shaft r is reversed, an
ascending motion is given to the balance cylinder d. In this way a reciprocating
motion may be imparted to the balance cylinder d.
In place of the racks and pinions 7, p and 9, 9 screws and screw boxes may be
employed. In this modification the screws have only a rotary motion in their
bearings the said screws being driven by toothed gearing from a driving shaft.
On the balance cylinder d screw boxes are fixed in which the screws described
work the balance cylinder being capable only of a sliding motion. By turning the
screws in one or other direction the screw boxes, on the sliding balance cylinder,
can be made to rise or fall upon the said screws and thereby cause the ascent or
descent of the balance cylinder.
In the rack and pinion or screw and screw box arrangement, the lift ram and
cage or platform are overbalanced as in the last described arrangement.
Although I prefer to load the sliding or balance cylinder with cast iron weights
or other weights yet the same effect may be produced, when water under pressure
is available by using additional single acting rams and cylinders of the kind
represented in Figure 1, the said single acting rams being placed in constant
communication with the pressure water.
Having now particularly described and ascertained the nature of my invention
and in what manner the same is to be performed I declare that I claim as my
invention of "Improvements in hydraulic lifts":-
The combination of an ordinary direct acting ram lift with a differential
accumulator or balance consisting of a fixed hollow ram (the upper part being of
less diameter than the lower part) connected with the lift cylinder and a hollow or
balance cylinder sliding on the said fixed hollow ram, the balance or sliding
cylinder being loaded so as to partially balance, to balance or overbalance the
dead weight of the direct acting ram and its attachments, the said balance or
sliding cylinder of the hydraulic lift being actuated by single acting rams or by
double acting pistons and rods or by racks and pinions or screws and screw boxes,
the several parts of the combined lift and balance mechanism being constructed,
arranged and working substantially as hereinbefore described and illustrated in the
accompanying drawing.
Dated the Fifteenth day of July 1892.
WILLIAM CARTER.