IMPROVEMENTS IN HYDRAULIC LIFTS
Year: 1881

page_text: LETTERS PATENT to John Sanders Stevens of Janus Works Queen's Road
Battersea in the County of Surrey and Charles George Major of Freke Road
Battersea in the County of Surrey. for an Invention of "IMPROVEMENTS IN
HYDRAULIC LIFTS"
PROVISIONAL SPECIFICATION left by the said John Sanders Stevens and
Charles George Major at the Office of the Commissioners of Patents on the
30th December 1881.
JOHN SANDERS STEVENS of Janus Works Queens Road Battersea in County
of Surrey and CHARLES GEORGE MAJOR of Freke Road Battersea in the County of
Surrey. "IMPROVEMENTS IN HYDRAULIC LIFTS."
This Invention has for its object improvements in hydraulic lifts and the
improvements have reference to that class of hydraulic lifts in which the carrying
cage is carried on the top of a direct acting ram which works in a long hydraulic
cylinder.
We construct this class of lifts in such a manner that when the ram and cage
are to be lifted water under pressure is supplied to the cylinder from an accumulator―
and when the cage has been raised to the required height the communication with
the accumulator is closed and the cage is thereby held in its elevated position.
When the cage is to be lowered a communication is opened between the lift
cylinder and a second hydraulic cylinder which is shorter but of larger diameter
the water in the lift cylinder can then as the lift ram descends pass into the
second cylinder and raise the ram of that cylinder. Above the top of the ram of
the second cylinder there is another ram rigidly fixed to it and working in a third
cylinder of less capacity and inverted.
This third inverted cylinder is connected by a pipe with the accumulator.
When the lift ram and cage descend and the rams of the second and third
cylinders are consequently raised water previously contained in the third cylinder
is forced out from it into the accumulator. When the lift ram and cage are to be
again caused to rise the communication between the second cylinder and lift
T

page_text: cylinder is closed and the communication between the lift cylinder and accumulator
is opened the lift ram and cage therefore rise. At the same time a communication
is opened between the second and third cylinders this allows the rams of these
cylinders to descend by their own weight and the water contained in the second
cylinder is forced upwards into the third cylinder so as to fill it-the surplus water
being led off by a pipe to a cistern. The communication between the second
cylinder and the third cylinder and cistern is closed when the communication
between the second cylinder and lift cylinder is opened. A non return valve is
placed on the pipe leading into the third cylinder and also a non return valve on
the pipe leading from the third cylinder to the accumulator so that the third
cylinder can only be filled through the one pipe and emptied through the other.
It will be evident that the two ends of a single cylinder with trunk piston rod
may be used instead of the second and third cylinders, also that the cylinders
might be moveable instead of the rams and that the cylinders need not necessarily
be placed vertically.
The net result of the above described series of operations neglecting loss by
friction is as follows:-
At the first operation water is drawn from the accumulator in sufficient quantity
to lift the load and the ram and cage.
At the second operation the water is withdrawn from the lift cylinder into the
second cylinder and simultaneously a body of water is forced from the third
cylinder into the accumulator equal to that withdrawn to lift the rain and cage
but not the load.
At the third step the water in the second cylinder is divided into two parts
that which did duty in lifting the ram and cage (useless work) goes to the third
cylinder to replace the equivalent quantity_paid_back_to_the-accumulator whilst
-that-portion-which-lifted the load (useful work) passes over to the store tank.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Sanders Stevens and Charles George Major in the Great Seal
Patent Office on the 30th June 1882.
JOHN SANDERS STEVENS of Janus Works Queens Road Battersea in the County
of Surrey and CHARLES GEORGE MAJOR of Freke Road Battersea in the County of
Surrey. "IMPROVEMENTS IN HYDRAULIC LIFTS"
This Invention has for its object improvements in hydraulic lifts and the
improvements have reference to that class of hydraulic lifts in which the carrying
cage is carried on the top of a direct acting ram which works in a long hydraulic
cylinder.
We construct this class of lifts in such a manner that when the ram and cage
are to be lifted water under pressure is supplied to the cylinder from an accumu-
lator and when the cage has been raised to the required height the communica-
tion with the accumulator is closed and the cage is thereby held in its elevated
position. When the cage is to be lowered a communication is opened between the
lift cylinder and a second hydraulic cylinder which is shorter but of larger
diameter the water in the lift cylinder can then as the lift ram descends pass into
the second cylinder and raise the rain of that cylinder. Above the top of the ram
of the second cylinder there is another ram rigidly fixed to it and working in a
third cylinder of less capacity and inverted.
This third inverted cylinder is connected by a pipe with the accumulator.
When the lift ram and cage descend and the rams of the second and third
cylinders are consequently raised water previously contained in the third cylinder
is forced out from it into the accumulator. When the lift ram and cago are to bo
again caused to rise the communication between the second cylinder and lift
cylinder is closed and the communication between the lift cylinder and accumu-
lator is opened the lift ram and cage therefore rise. At the same time a com-
munication is opened between the second and third cylinders this allows the rams
of these cylinders to descend by their own weight and the water contained in the
second cylinder is forced upwards into the third cylinder so as to fill it-the
surplus water being led off by a pipe to a cistern. The communication between
the second cylinder and the third cylinder and cistern is closed when the com-
munication between the second cylinder and lift cylinder is opened. A non-return
valve is placed on the pipe leading into the third cylinder and also a non return
valve on the pipe leading from the third cylinder to the accumulator so that the
third cylinder can only be filled through the one pipe and emptied through the
other.
It will be evident that the two ends of a single cylinder with trunk piston rod
may be used instead of the second and third cylinders also that the cylinders
might be moveable instead of the rams and that the cylinders need not necessarily
be placed vertically.
The net result of the above described series of operations neglecting loss by
friction is as follows.-
At the first operation water is drawn from the accumulator in sufficient quantity
to lift the load and the ram and cage.
At the second operation the water is withdrawn from the lift cylinder into the
second cylinder and simultaneously a body of water is forced from the third
cylinder into the accumulator equal to that withdrawn to lift the ram and cage
but not the load.
At the third step the water in the second cylinder is divided into two parts
that which did duty in lifting the ram and cage (useless work) goes to the third

page_text: cylinder to replace the equivalent quantity paid back to the accumulator whilst
that portion which lifted the load (useful work) passes over to the store tank.
The Drawing annexed shews a diagram view of an hydraulic lift constructed as
above described. A is the cage carried on the top of a long ram B which works
in a cylinder C. From this cylinder passes a pipe D to a three way cock E from
which cock also passes a pipe F to an accumulator and a pipe G to a second
hydraulic cylinder H from this pipe Ga branch pipe I rises to the third eylinder K,
which is vertically above the second cylinder H. H'K' are the two rams which
are attached together and which work in the cylinders H. K. respectively. L is a
cock on the pipe G which is coupled as shewn to the three way cock E so that
when a quarter turn is given to one a quarter turn is given to the other. M is a
non return valve in the pipe I. N is a branch from the pipe I leading to a store
tank. O is a pipe leading from the cylinder K to the accumulator. P is a non-
return valve on this pipe, R is an endless chain by which the tap E and with it
the tap L can be turned into either one or other of the two positions indicated by
the radial dotted lines. The chain can be acted upon by any one within the cage
just as in other hydraulic lifts when the raising and lowering of the cage is effected
by the opening and closing of a valve or valves. When the taps E. L are turned
so that their radial arms are in position X the cock E cuts off the communication
between the pipe D and the accumulator and connects it with the pipe G leading
to the second cylinder H whilst the cock L is closed. When the cocks are turned
into position Y the cock L is opened and the cock E connects the pipe D to the
accumulator, and cuts it off from the pipe G leading to the second cylinder. The
working of the apparatus is clearly described above.
Having thus described the nature of our Invention and the manner of per-
forming the same we would have it understood that we claim_the_construction-of-
hydraulic lifts substantially-in-the-manner herein before described.
In witness whereof we the said John Sanders Stevens and Charles George
Major have hereunto set our hands and seals this Twenty third day of
June in the year .of our Lord One thousand eight hundred and eighty two.