Improvements in Hydraulic Cranes, Lifts, and the like,
Year: 1899

page_text: Date of Application, 25th Mar., 1899
Complete Specification Left, 23rd Dec., 1899-Accepted, 24th Feb.,
1900
Improvements in Hydraulic Cranes, Lifts, and the like,
I, WILLIAM BARTHOLOMEW COLE, of 9, Thornhill Road, Leyton, in the County of
Essex, Engineer, do hereby declare the nature of this invention to be as follows:-
This invention has reference to hydraulic cranes, lifts, and the like, and it has for
object to economise, in a simple, effective and cleanly manner, the pressure liquid
hereinafter referred to as water, used in such cranes and lifts.
I will describe my invention with reference to a hydraulic crane in which the
lifting is performed by a ram with a chain or chains or the like, as follows:-
In connection with the lifting ram I provide a differential ram in which the larger
area may be in connection with the lifting ram and the smaller area may be in
connection with the main pressure pipe, and I also provide a controlling value or
valves for the lifting ram and the differential ram, either in combination or separately,
the said valves being so arranged that the lifting rain may be disconnected from the
larger area of the differential ram and placed in communication with the main
pressure pipe, or the lifting ram may be placed in communication with the larger
area of the differential ram and the smaller area of said differential ram in communica-
tion with the main pressure pipe; and I further provide in connection with the larger
area of the differential ram an escape or relief valve, the arrangement being such that
when the controlling valve or valves is or are moved into one position the lifting ram
will be placed in communication with main pressure pipe, and the larger area of the
differential rain disconnected so that the main pressure water may act on the lifting
ram, effecting the lift at high pressure. Another position of the controlling valve or
valves disconnects the lifting ram from the main pressure pipe and connects the
larger area of the differential ram with the lifting ram and the smaller area of said
differential ram is placed in connection with the atmosphere so that water can pass
from the lifting ram to the cylinder containing the larger area of the differential ram,
forcing the larger area ram into (or from) its cylinder and displacing the smaller area
ram, any water in excess of the contents of said cylinder of larger area ram being allowed
to escape by means of the escape or relief valve before mentioned. Another position
of the controlling valve or valves connects the larger area of the differential ram with
the lifting cylinder and the smaller area with the main pressure pipe, water being
forced from the larger area of said differential ram into the lifting cylinder and the
lift effected at low pressure.
The differential ram may conveniently be contained in one cylinder; or by another
arrangement one cylinder may contain two differential rams.
The controlling valves may be of the piston and cup leather type or of the mitre
type, or other suitable construction.
The relief or escape valve may be of the piston & cup leather type or of the mitre
type, or any other suitable construction, and may be loaded either by a spring or
weight to withstand the pressure developed in the cylinder containing the larger area
of the differential ram with which one side of said valve is always in connection, the
other side being open to the atmosphere; and with a second spring or weight of
sufficient load-which is constant,-to withstand the head of water, if any, in the
connecting pipes, cylinder of lifting ram, and other parts if necessary, but not of

page_text: sufficient load to withstand the pressure that is produced in the cylinder containing
the larger area of differential ram by the falling or in-stroke of the lifting ram.
By an arrangement of rods and levers or the like, actuated by the smaller area ram
of the differential ram, the relief valve may be automatically relieved of the heavier
load when the cylinder with which it is in connection becomes fully charged with
water, thus allowing any surplus water to escape to the atmosphere, and also being
the means of connection of the lifting cylinder with the atmosphere, by which
arrangement the cylinder containing the larger area of the differential ram is always
charged with water in readiness for a light lift operation.
All the apparatus above mentioned may conveniently be applied in a like manner
to cranes or lifts of the direct acting type.
D
Improvements in Hydraulic Cranes, Lifts, and the like.
I, WILLIAM BARTHOLOMEW COLE, of 85 Pathfield Road, Streathani Common, in
the County of Surrey (formerly of 9, Thornhill Road, Leyton, in the County of Essex),
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 :---
This invention has reference to hydraulic cranes lifts, and the like, and has for its
object to economise in a simple, effective and cleanly manner the pressure liquid
(hereinafter referred to as water) used in such cranes and lifts.
I will describe my invention with reference to a hydraulic crane in which the
lifting is performed by a ram with a chain or chains or the like, reference being made
to the accompanying drawing in which :-
Figure 1 shows the general arrangement of my invention with the controlling
valves in the exhaust position.
Figure 2 is a sectional view of the relief valve in the closed position.
Figure 3 is a sectional view showing the controlling valves in position for a light
lift operation, and
Figure 4 is a sectional view showing the controlling valves in position for a heavy
lift operation.
The same reference letters indicate the saine parts in the different figures.
In connection with the lifting ram a in the crane cylinder a¹ I provide a
differential ram b in a cylinder 6' the larger area 6* of said ram 6 being in communi-
cation by pipes c, c, with the lifting ram a and the smaller area d² in
communication with the main pressure pipe d by pipe . I provide in the pipe
connections between said rams a and b controlling valves e e¹ which control the
pressure admitted to the lifting and differential rams for the different lifting opera-
tions said valves being so arranged in combination with the pipe connections between
the lifting and differential valves that the lifting ram a is disconnected from the
larger area 62 of the differential ram b and placed in direct communication with the
main pressure pipe d so as to admit high pressure water direct to the crane cylinder a¹
when a load is on the crane hook, the larger area 62 of differential ram 6 being cut off
from communication with cylinder a¹ by means of valve g¹ which is closed by back
pressure on the other hand when the crane hook is light communication between
the main pressure pipe d and crane cylinder a is cut off and communication opened
between said main pressure pipe and the smaller area of the differential ram b,
•

page_text: communication being also opened between the larger area 62 of said ram b and the
ram a in the crane cylinder. The exhaust from the crane cylinder a is also controlled
by the valves e e¹ and relief valve f as more clearly described hereinafter, said relief
valve f being operated by differential ram on its down stroke to discharge any
excess of water from the cylinder b¹.
•
The controlling valve e consists of a piston g having differential areas, and a mitre
valve g¹ which latter is connected by means of a slotted link and rod ¹ to the
operating lever j: the piston valve g of the valve e is weighted by rod and weight k
so as to be normally held down for the light lift operation the movement of the
piston g being limited by stops formed in the valve box.
The valve e¹ is of the ordinary controlling valve construction, and both valves are
provided with the usual leathers or other watertight packing. This valve also be made
on the double mitre valve principle or other usual construction without in any inter;
fering with the operations.
I will now describe the working of my invention for light and heavy lift operations
respectively.
The position of the controlling valves e e¹ being as shown in Figure 3 and the relief
valve fas in Figure 2, to perform a light lift operation water at high pressure is
admitted to said controlling valves through pipe and port d and flows into the annular
space in cylinder 6' by means of the pipe and port forcing up the differential
ram 6 and sending the water contained in the cylinder 61 through the pipe c, relief
valve f, pipe c', through the mitre valve 9', port and pipe c² into the crane cylinder a¹
forcing up the lifting ram a and so drawing up the chain and hook.
The position of valves e e¹ being as in Figure 4 and relief valve f as in Figure 2 in
the case of a heavy lift operation, the resistance offered by the differential ram 6 to
movement will cause pressure upon the piston g of the valve e of which the upper por-
tion is of slightly larger area than the lower portion and enable it to overcome the
weight & thus opening a way for high pressure water to pass direct from the main
pressure pipe through pipe and port into the crane cylinder a¹, the back pressure
on the mitre valve g¹ causing it to close and cut off communication with the cylinder b
of the differential rain, this automatic movement of said mitre valve being per-
mitted by the slotted link h.
To allow the crane ram a to exhaust and return to the bottom of the cylinder a¹
the position for the controlling valves e e¹ and the relief valve will be as shown
in Figure 1. The piston m of valve e¹ is moved into its bottom position, by means of
lever, connecting the annular space d in cylinder b with the exhaust pipe and port
the weight of the ram in cylinder al causing the water in said cylinder to flow
through pipe and port c¹ into valve e and through the mitre valve g¹ (which is opened
at the same time as the piston m of the valve e is put into its lowest position by the
operation of lever ;), through pipe c¹, relief valve f and pipe c into cylinder 6¹
forcing out the differential ram 6 will open the relief valve f by striking the weighted
lever (n or a connection thereto) so that any excess of water will escape through the
relief valve into pipe o and run to waste.
According to the arrangement above described the cylinder 6¹ is always charged
with water in readiness for a light lift operation, and it will be seen that for a light
lift operation only a comparatively small quantity of high pressure water is employed
in the cylinder bi acting on the smaller area d² of the differential ram b therein: no
higher pressure water is employed in the crane cylinder a¹ for a light lift.
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 dis-
tinctly understood that I am aware that differential rams have been employed before
in hydraulic presses and the like for the purpose of economising high pressure water.
I am also aware that automatic controlling valves have been used before. I there-
fore do not claim these broadly, but what I do claim is :—
1. The herein described improvements in hydraulic cranes whereby high pressure
water only is automatically admitted from the pressure supply pipe direct to the

page_text: crane cylinder for the purpose of drawing up the chain when the crane hook is
loaded, and low pressure water only is automatically admitted to the crane cylinder
from the cylinder of the differential rain for drawing up the chain when light,
substantially as and for the purposes set forth and as illustrated in the accompany-
ing drawings.
2. In hydraulic cranes and the like the combination of a lifting ram, a differential
ram, automatic controlling valves for said lifting and differential rams, and a relief
valve operated by the differential ram, all substantially as herein described for the
purposes specified and as illustrated in the accompanying drawings.
3. In controlling valves for hydraulic cranes and the like, the combination with a
differential piston valve and an ordinary piston valve, of a check valve adapted to be
operated by hand for admitting low pressure water to the crane cylinder and for
exhausting from the crane cylinder and automatically by pressure from the
differential ram for admitting low pressure water to the crane cylinder for a
light lift, substantially as herein set forth.
1000
JOHN P. O'DONNELL, Fel. Chart. Inst. P.A.,
Agent for Applicant, 70/1, Palace Chambers, Westminster, S.W.