IMPROVED MEANS AND APPARATUS FOR COMMUNICATING FLUID PRESSURE TO WORK MOVEABLE MACHINERY
Year: 1880

page_text: LETTERS PATENT to Charles Algernon Parsons and William Cross, both of
Elswick, in the Borough and County of Newcastle upon Tyne, Engineers, for an
Invention of "IMPROVED MEANS AND APPARATUS FOR COMMUNICATING FLUID
PRESSURE TO WORK MOVEABLE MACHINERY."
PROVISIONAL SPECIFICATION left by the said Charles Algernon Parsons
and William Cross at the Office of the Commissioners of Patents on the 26th
February 1880.
CHARLES ALGERNON PARSONS and WILLIAM CROSS, both of Elswick, in the
"IMPROVED MEANS
Borough and County of Newcastle upon Tyne, Engineers.
AND APPARATUS FOR COMMUNICATING FLUID PRESSURE TO WORK MOVEABLE
MACHINERY."
Our Invention relates to means and apparatus for communicating fluid pressure
to work moveable machinery, such as, for example, hydraulic cranes, hydraulic
rivetters, and other machines that have to be moved from place to place according
to the demands of the work which they have to perform. For this purpose wo
connect the cylinder or other part of the machine in which the fluid has to act to
an outer pipe of some length, which can slide to and fro along a smaller inner pipo
connected to the pump, accumulator, or cistern that supplies the working fluid.
The inner pipe is closed at its end, and passes through stuffing boxes at the ends
of the outer moveable pipe. At intervals along its length the inner pipe has
lateral apertures provided with valves, any one of which when open permits fluid
to flow from the inner pipe into the annular space surrounding it in the outer pipe
by which it is conveyed to the machine. Each of these valves is so arranged
that it is kept closed by the pressure of the fluid except when that pressure
is sufficiently relieved to permit the valve to be opened by a spring. For
the purpose of so relieving the pressure the valve stem is attached to a
piston fitted to work in a cylindrical cavity in the inner pipe. The part
of this cavity under the piston communicates with two side ports, one of them
some distance in advance of the valve, and the other some distance behind it,
and both having check valves opening outwards. When the two ports are open to
the annular space in the outer pipe, in which space the pressure is nearly equal to

page_text: that in the inner pipe, this pressure acting under the piston balances so much
of the pressure keeping the valve seated that the spring raises the valve and
permits fluid to flow from the inner pipe into the annular space of the larger pipe
whence it supplies the inachine. If by the movement of the machine from one
place to another the outer pipe moving with it is shifted into such a position
relatively to the inner pipe that either of the two ports above mentioned is no
longer within the outer pipe, then the pressure under the valve piston being relieved
by escape of fluid through the port thus uncovered, the valve is held down to its
seat by the excess of pressure in the inner pipe.
By so spacing the valves and their ports along the inner pipe that there is at
least one set of them within the length of the outer pipe, there is always a supply
of fluid available for working the machine, notwithstanding that the machine may
be moved relatively to the supply pipe.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Charles Algernon Parsons and William Cross in the Great Seal
Patent Office on the 21st Augu. + 1880.
"
CHARLES ALGERNON PARSONS and WILLIAM CROSS, both of Elswick, in the
Borough and County of Newcastle upon Tyne, _Engineers. IMPROVED MEANS
AND APPARATUS FOR COMMUNICATING FLUID PRESSURE TO WORK MOVEABLE
MACHINERY."
Our Invention relates to means and apparatus for communicating fluid pressure
to work moveable machinery, such as, for example, hydraulic cranes, hydraulic
rivetters, and other machines that have to be moved from place to place according
to the demands of the work which they have to perform. For this purpose we
connect the cylinder or other part of the machine in which the fluid has to act to
an outer pipe of some length, which can slide to and fro along a smaller inner pipe
connected to the pump, accumulator, or cistern that supplies the working fluid.
The inner pipe is closed at its end, and passes through stuffing boxes at the ends of
the outer moveable pipe. At intervals along its length the inner pipe has lateral
apertures provided with valves, any one of which when open permits fluid to flow
from the inner pipe into the annular space surrounding it in the outer pipe by
which it is conveyed to the machine. Each of these valves is so arranged that
it is kept closed by the pressure of the fluid except when that pressure is
sufficiently relieved to permit the valve to be opened by a spring. For the
purpose of so relieving the pressure the valve stem is attached to a piston fitted
to work in a cylindrical cavity in the inner pipe. The part of this cavity
under the piston communicates with two side ports, one of them some distanco in
advance of the valve and the other some distance behind it, and both having check
valves opening outwards. When the two ports are open to the annular space in
the outer pipe, in which space the pressure is nearly equal to that in the inner

page_text: pipe, this pressure acting under the piston balances so much of the pressure keeping
the valve seated that the spring raises the valve and permits fluid to flow from the
inner pipe into the annular space of the larger pipe whence it supplies the machine.
If by the movement of the machine from one place to another, tho outer pipe
moving with it is shifted into such a position relatively to the inner pipe that
either of the two ports above mentioned is no longer within the outer pipe, then
the pressure under the valve piston being relieved by escape of fluid through the
port thus uncovered, the valve is held down to its seat by the excess of pressure in
the inner pipe.
By so spacing the valves and their ports along the inner pipe that there is at
least one set of them within the length of the outer pipe, there is always a supply
of fluid available for working the machine, notwithstanding that the machine may
be moved relatively to the supply pipe.
Fig. 1 is a side view,.and Fig. 2 an end view of a hydraulic supply pipe with
apparatus according to our Invention applied to it, and Figs. 3 and 4 are respec-
tively longitudinal and transverse sections to an enlarged scale, shewing one of the
valve arrangements with which the supply pipe is provided. The supply pipe A
is inade of any length required for the travel of the crane or other inachine, its
parts being screw jointed together, as shewn in Fig. 3, with a cylindrical valve
box B interposed between the adjacent lengths, the whole pipe, including the valve
boxes which form the junctions of its lengths, being turned or otherwise shaped
truly cylindrical on its exterior, so that it can slide without leakage through stuffing
boxes at the ends of a sleeve pipe C, which extends over and encloses a considerable
length of the pipe A, leaving a free annular space between the exterior of the pipe
and the interior of the sleeve. The sleeve C is attached to the travelling hydraulic
machine with which it communicates by a pipe D. It is of advantage to make this
pipe D bent and somewhat flexible, and to support the sleeve C by a spring E on a
bracket projecting from the machine, so that the sleeve can yield a little to
inequalities in the movement of the machine without straining the pipo A which
the sleeve embraces. When there is a considerable length of pipe A it may be
supported at suitable intervals by levers F, having elastic pads fon which the
pipe A rests. The levers F are counterweighted sufficiently to bear the weight of
the pipe, their counterweights G usually resting on blocks. The front end of each
of the levers F carries a roller H, on which cither of the sloped ends h of the
machine frame comes to bear as the machine is moved to or fro. The slope of h
depresses the lever F sufficiently to permit the passage of the sleeve pipe C which
travels with the machine, and when C has passed the lever F is again raised by its
counterweight to support the pipe A. The pipe A is provided at intervals with
valve boxes, such as are shewn in Figs. 3 and 4, the distance from valve box to
valve box being somewhat less than the length of the sleeve pipe C, so that
wherever that sleeve pipe may be there is at least one of the valves boxes within
its length. The valve box has an aperture to the annular space within the sleeve,
this aperture being fitted with a valve K. The stem of the valve K works through
cup leathers at the mouth of a cylindrical cavity L formed in the valve box, and
it has fixed on it a piston M packed with cup leather. Within the stem which is
hollow is a helical spring W arranged to unseat the valve K, but this spring is not
sufficiently strong to unseat the valve in opposition to the pressure of the liquid
within, the pipe A tending to keep the valve seated when that pressure is not
counterbalanced. The cylindrical cavity L communicates at its upper part by a
passage with the interior of the pipe A, and at its lower part by a a passage 12
with the middle of another cavity in which is fitted a double ended valve N. The
spaces above and below this valve communicate by passages O and P with the
annular space within the sleeve pipe C, the mouths of O and P being at some

page_text: distance apart, as shewn in Fig. 3. When the sleeve pipe C is moved with the
machine along the pipe A there is always one of the valve boxes having the mouths
of its passages O and P wholly within the sleeve, which is made of sufficient length
for that purpose. The pressure in the annular space of the sleevo being nearly the
same as that within the pipe A this pressure communicated through the passages
O and P, past the valve N which is in balance, and through the passage acts on
the underside of the piston M, and the force of the spring W conspires with it to
raise the valve K off its seat. The liquid from A is thus permitted to flow into
the annular space of the sleeve C, and thence by the pipe D to work the machine.
When by the travel of the machine and the sleeve C either or both of the mouths
of O and P come out beyond the stuffing box at either end of the sleeve, then as
liquid escapes by the passage and past the valves N, the underside of the piston
M is relieved from pressure and consequently the valve K is closed. As the mouths
of O and P are at some distance beyond the valve K in each direction the valve K.
will obviously become closed before it passes out beyond the stuffing box of the
sleeve C, escape by either of those mouths, causing the valve K to be closed. Thus
as long as the mouths O and P of any of the valve boxes in the line of the pipe A
are both within the travelling sleeve pipe C that sleeve pipe is supplied by the
open valve K with liquid under pressure, which is communicated to the machine
to which C is connected; but when by the travel of the machine and the sleeve
pipe the stuffing box at its end passes either of the mouths O or P the valve K is
closed, and escape of the liquid from A is prevented. The levers F and their
pads are arranged immediately under the valves K, so as to close the apertures of
the pipe A when it rests upon them.
Having thus described the nature of our Invention, and in what manner the
same is to be performed, we claim,―
First. Communicating fluid pressure to work a moveable machine by means of a
stationary pipe laid parallel to the line of travel of the machine, and passing
through stuffing boxes at the ends of an enclosing sleeve pipe connected to and
travelling with the machine, the stationary pipe being furnished at suitable
intervals with valves, so arranged that each valve opens to give passage for the
fluid from the pipe only when it is wholly within the sleeve, substantially as herein
described.
Second. The construction and arrangement of valve for operating in the manner
referred to in the preceding claim, substantially as herein described with reference
to Figs. 3 and 4 of the accompanying Drawings.
In witness whereof, I, the said Charles Algernon Parsons, have horeunto set
my hand and seal, this Seventeenth day of August, in the year of our Lord
One thousand eight hundred and eigty.