IMPROVEMENTS IN HYDRAULIC PRESSES, WHICH ARE IN WHOLE OR IN PART APPLICABLE TO PUMPS AND OTHER LIKE MACHINES
Year: 1849

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, Baron
LOUIS LO PRESTI, formerly of Paris, in the Republic of France, but now of
Vienna, in the Empire of Austria, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Tenth day of December,
One thousand eight hundred and forty-nine, in the thirteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Baron Louis Lo Presti, my exors, admors, and assigns, Her especial
licence, full power, sole privilege and authority, that I, the said Baron Louis
Lo Presti, my exors, adññors, and assigns, or such others as I, the said Baron
Louis Lo Presti, my exors, admiors, or assigns, should at any time agree with,
and no others, from time to time and at all times during the term of years
therein expressed, should and lawfully might make, use, exercise, and vend.
within England, Wales, and the Town of Berwick-upon-Tweed, my Invention
of "IMPROVEMENTS IN HYDRAULIC PRESSES, WHICH ARE IN WHOLE OR IN PART
APPLICABLE TO PUMPS AND OTHER LIKE MACHINES;" in which said Letters Patent
is contained a proviso, that I, the said Baron Louis Lo Presti, shall cause a
particular description of the nature of my said Invention, and in what manner
the same is to be performed, by an instrument in writing under my hand and
seal, to be inrolled in Her Majesty's High Court of Chancery within six
calendar months next and immediately after the date of the said in part
recited Letters Patent, as in and by the same, reference being thereunto had,
will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Baron Louis Lo Presti, do hereby declare that the nature of my said Invention,

page_text: and in what manner the same is to be performed, are fully described and
ascertained in and by the present Specification thereof, reference being had to
the Drawings hereunto annexed, that is to say: -
Hydraulic presses are constructed on the principle that, if pressure is applied
to any portion of the surface of a liquid contained in a water-tight vessel, that
pressure will be repeated on the sides of the vessel as often as the portion of
the surface of the liquid, to which pressure was first applied, is contained in the
sum of the surfaces of the sides. They commonly consist of a large cylinder
fitted with a piston or ram, and of a small lifting and forcing pump, which is
in communication with the cylinder, and supplies it with water or other liquid,
and as this pump is worked with a lever, great pressure is exerted on its piston
or plunger, which produces on the ram a power equal to the pressure applied
to the plunger of the pump, multiplied by the ratio which the surface of the
plunger bears to that of the ram. Now, it follows from these premises that
the greater the difference between these surfaces, the greater will be the
amount of pressure obtained. This pressure is applied to the compression of
substances by placing them between the head of the ram and a fixed plate
which is suitably attached to the cylinder by iron bars. If, for example, one
pump only were employed, the ram of the cylinder would be moved forward
according to the quantity of water furnished by the pump, and would therefore
act at one uniform degree of pressure from the commencement to the end of
the operation. But inasmuch as the substances to be pressed offer generally
'less resistance at the commencement than at the end, let us suppose two
pumps of different capacities to be used, the larger at the beginning to move
the ram more rapidly by the introduction of a larger quantity of liquid, and
the smaller towards the end of the operation, in order to impart a greater force
to the ram; then it is evident that by employing a series of pumps of different
capacities, we should be able to communicate to the ram a rapidity of motion
in inverse proportion to the resistance of the substances to be compressed;
that is to say, it will travel fast at the commencement of its rise, and gradually
diminish in speed towards the end, when its movement will be very slow, in
consequence of the smallest pump being employed. But the use of a series of
pumps would be a matter of great expence, especially for hydraulic presses
employed to compress soft matters, such as hay or cotton, and in practice
seldom more than two pumps are used, whereby considerable time is lost.
Now, the object of my Invention is to remedy that defect; firstly, by substi-
tuting for a series of pumps a combination of machinery which shall produce
the same results and not be of expensive construction. For this purpose I
'have invented the several methods, next herein-after described, of effecting the

page_text: said combination, preferring, nevertheless, the first of these, because of the
superior simplicity of its construction, and its capability of being adapted to
presses already in use at little cost. My Invention may be said to be based on
the principle that the result of a force employed to overcome a certain amount
of resistance, multiplied by the speed thereof, id est, the distance travelled in
an unit of time, is always equal to the resisting force multiplied by its speed;
from which principle I deduce as a corollary, that the resistance to the small
plunger being feeble at commencement, and becoming stronger by degrees, as
the substances are compressed, I am enabled to change the speed of the
force which is employed, and therefore give more strokes of the plunger at the
commencement, diminishing them gradually until the end of the operation, yet
cause the ram of the cylinder to travel faster at the beginning than at the
conclusion thereof.
Figure 1 (an exterior elevation), Figure 2 (a side elevation, Figure 3
(a plan) in Sheet 1 of the Drawings, represent my first improvements in
hydraulic presses to be worked by hand power, and Figures 5 and 6 are
detached views on an enlarged scale of some of the parts thereof. A is the
barrel of the pump; B, the plunger which is attached to about the centre of
the piston rod C, which passes through the stuffing boxes D, D, fixed to the
valve boxes E, E. These valve boxes are attached to the top and bottom of
the barrel of the pump A, to enable the piston B to force water at each up and
down stroke into the cylinder K, through the pipes F, F, which are united as
indicated in the Drawing, Figure 1; H is a reservoir of water, containing
a sufficient quantity to drive the ram I to the full extent of its course. The
water flows through the pipes J, J, into the top and bottom valve boxes E, E,
and is forced into the cylinder K by the action of the plunger B. The
reservoir H is supported on a table L, a little above the upper valve box E.
The piston rod C is connected by hooks O, O, to the cords P, P, which pass
over two pulleys M, M, the lower one of which is fixed to the ground and the
upper one supported in the top of a frame N; the other ends of the cords
P, P, are attached separately to two escapement wheels Q, Q, which are
keyed upon the same axle. To prevent the cords from twisting, they aro
divided at about the centre, and subsequently united by the shackles R, R;
between the escapement wheels Q, Q, there is keyed upon the same axle a
toothed wheel S. which receives rotary motion from another toothed wheel T,
of the same diameter; one end of the axle of the wheel T is squared to
receive the crank U, which carries the sliding handle V, which may be fixed
at pleasure by means of the catch X acted on by the spring y, (shewn on an
enlarged scale in Figure 6,) in any one of the positions indicated by, the holes

page_text: 1, 2, 3 and 4, in the crank U, Figure 1. The catch which takes into one of
these holes, and is kept in position by the spring, has to be bent back to
withdraw it, and to allow of the position of the handle being changed for the
purpose of increasing or diminishing the leverage as required. A pinion a
is supported in the frame Z, which carries the two toothed wheels S, T, and
gears into the latter (T); one end of the axle of the pinion is also mado
square, and of the same size as that of the axle of the toothed wheel T, to
receive the handle when the pressure reaches a certain limit, for the purpose
of increasing the power in order to carry it beyond that point. To begin
working, the reservoir is once for all filled with water, and the crank
placed on the axle of the wheel T; the handle is fixed in the hole No. 1, as
shewn in the Drawing, and rotary motion communicated to it, whereby the
wheel T will be made to revolve as well also as the wheel S, which will
cause the escapement wheels or pullies Q, Q, to rotate, the one winding up
its cord on the projecting part (shewn on an enlarged scale in Figure 5),
and the cord of the other escapement wheel hanging loose. The cord which
is being wound up will move the plunger B, and eject the water as in the
ordinary pump, until the cord reaches the extremity of the projection at the
point 6, when it will slide off and unrol itself; at this moment the other
escapement wheel or pulley, which has accomplished half of a revolution,
begins to wind on its cord, whereby the piston will be moved in the reverse
direction, and the projecting portion being the same in this instance as in the
preceding, the cord will at a certain point slide off and be unrolled. By sub-
stituting these escapement wheels or pulleys for two cranks or eccentrics
which might have been employed, an advantage is gained, because the distance
travelled in one revolution of the pulleys is three times the diameter thereof,
which produces two strokes of the plunger; while by using cranks or eccentrics
with the same leverage, twice the diameter only would be travelled over.
Figures 4 and 4*, Sheet 1 of the Drawings, represent part of a hydraulic press,
to be worked by a steam engine or other prime mover, constructed according
to my invention. A is the main driving shaft, on which is keyed the conical
pulley b; c is a second conical pulley keyed on the shaft d, which is opposite
to the apex of the cone b. A driving band h passes round the two pulleys e
and f, and communicates the motion derived from the prime mover to the
pulley keyed upon the shaft which in turn imparts rotary motion to the
'pulley f, of the same diameter as the pulley e. The pulley f is mounted on the
shaft, at the ends of which are keyed the escapement wheels g,g. I is a lever
(attached to the cord J which passes over a pulloy, and is connected to the
ram), which causes the driving band H to slide along the conical pulleys b, c.

page_text: The reciprocating motion is communicated from the escapement wheels g, g,
to the plunger, as in the hydraulic press firstly herein-before described.
Figure 4b, Sheet 2, is a longitudinal elevation partly in section, and
Figure 4º, an end elevation of an apparatus for injecting a continuous stream.
of water into a hydraulic press, instead of the arrangement which has been
just described. A is the barrel of the pump fixed at top to the under part of
the water reservoir B. A number of pistons C, C, C, C, working in the barrel
A, ure fixed at equal and determinate distances upon the endless cord D, which
passes over a pulley E (supported in standards F, attached to the reservoir B)
down the barrel A, and under a second pulley G (centred in a box H'
affixed to the lower part of the barrel A), then up the pipe Y (opening into the
box H at bottom, and the reservoir Bat top), and last over the driving pulley I.
The axle M of the driving pulley I turns in bearings in the frames J, J, and
has keyed upon it a toothed wheel K, into which gears a pinion L, keyed on a
second shaft N, also supported in bearings in the frames J, J. Two valves
O, O, faced with caoutchouc or other suitable material, and which turn on
pivots, are made to close the end of the barrel by pressing tightly against it.
The valves have two semicircular holes cut in the opposite sides, to admit of
the passage of the endless band D between them; on motion being communi-
cated to the pulley I, by means of the handle P, the endless band D will
travel in the direction of the arrow and the piston C, which enters the barrel
A, will compress between it and the valves O, O, the water that shall have
previously flowed therein from the reservoir B, and cause it to open the the
valve Q, when it will be forced through the pipe R into the press. When the
piston C has arrived close to the valves O, O, the eccentric S, keyed on the
axle M. will push the rod T, which will act on the levers U, U, so as to move-
the rods V, V, in the reverse direction, and allow the valves O, O, to fall down
to admit of the passage of the piston between them. When the piston has.
passed the valves, the eccentric will cease to act upon the rod T, which will be
pushed back by the spring X, so as to bring the valves O, O, into their first
positions, and close the barrel A. A portion of water will be carried with the
piston into the box or case H, and into the pipe Y, which cominunicates with.
the water reservoir B. The shaft M is fitted with a sliding handle, as in the-
apparatus firstly herein-before described, whereby four different degrees of
velocity can be imparted to it; after which the handle may be placed on the
shaft N, and, through the intervention of the pinion L, four fresh degrees of
velocity will be communicated to the main driving pulley. Figure 4d is an
exterior elevation of another arrangement for communicating the to-and-fro.
movement to the plunger; U is the handle, which is worked in the same

page_text: way as before. A and D are two toothed wheels which gear into one another,
and have keyed on their respective spindles two other wheels C and E,
having teeth on portions only of their peripheries. F is a toothed rack fixed
to the top of the plunger, into which gear respectively the partially toothed
wheels C and E, whereby the necessary to-and-fro motion will be commu-
nicated to the plunger.
Secondly, my invention consists of a method of constructing the rams of
hydraulic presses, whereby I am enabled to obtain different degrees of velocity.
Figure 1, Sheet 2 of the Drawings annexed, is a sectional elevation of a ram,
constructed of five different diameters; A is a pipe which conducts the water
from the pump to beneath the surface B of the part No. 1, which is the
smallest in diameter. As soon as the water is forced in, the ram will ascend
rapidly, in consequence of the small volume of water required to displace it.
The power obtained will be in the ratio of the surface B to that of the plunger
of the pump, multiplied by the power communicated by the lever from the
workinan to the plunger. As soon as the portion No. 1 passes beyond the
first joint, the water will act upon the surface c of the division, No. 2, of the
ram, as well as upon the surface B. The ram will then ascend less rapidly
than before, but will give out an increased degree of pressure, and so on
throughout the series 3, 4, 5, the water acting upon their surfaces successively,
whereby the speed of the ram will be progressively decreased and its pressure
increased. When it is desired to exert the whole pressure at the beginning,
water is forced in through the pipes D and A, which open into one another, at
a point of junction, as shewn in the Drawings, and communicate by means of
the cocks F, F. When the operation is terminated, the water is drawn off' by
the pipes G and H by opening the cock I and a valve placed on the pipe H,
as in the ordinary hydraulic press. The water, compressed by the intermediate
portions of the ram 2, 3, and 4, passes by the channels a, b, c, and returns into
the large ono, whence it escapes by the pipe H.
Figure 2, Sheet 2 of the Drawings annexed, is a sectional elevation of another
mode of constructing an hydraulic ram for obtaining the same object, namely,
variable degrees of speed and pressure. A is the ram, pierced with (say) seven
holes, in which are adjusted as many hollow stoppers B, C, D, E, F, G, H,
shewn in Figure 3 (a plan) of the Drawings of different lengths fixed underneath
the cylinder, which they close completely. The stoppers are supported in
the box I attached to the bottom of the cylinder, and carry at top valves
b, c, d, e, f, g, h, which open upwards. Water is forced into the cylinder as before,
through the pipe K, and acts upon the lower surface of the ram which encircles
the stoppers, whereby it will be raised, and the shortest stopper B withdrawn. lp

page_text: this case the surface of the ram will be augmented by that of the stopper, and
will consequently move upwards with a greater force, but at a less rate of speed.
As the water is pumped in, the ram continues to ascend, whereby the stoppers
will be successively withdrawn from their respective chambers. The effect of this
will be to successively increase the power and decrease the speed of the ram.
As the ram ascends and the stoppers are withdrawn, a partial vacuum is created
in their respective chambers (within the ram), into which the valves will open
and allow the water to flow in through the hollow stoppers from the pipe L
which communicates with a reservoir of water; when the substances have
been sufficiently compressed, and it is desired to bring the ram down into its
first position, the screw M is turned by hand or other power, whereby the plate
N (a plan of which is given separately in Figure 4, Sheet 2) will be pushed
up, which will have the effect of forcing the rods 1, 2, 3, 4, 5, 6, and 7
(Figure 5, Sheet 2 of the Drawings) up the hollow stoppers, within which they
are respectively placed. The ascent of these rods will force open the valves
b, c, d, e, f, g, h, in the upper part of the stoppers, and allow the water which
was contained above them within the hollows of the ram to flow out, which
otherwise would be compressed by the stoppers in the hollows when the ram
descended.
Figure 6, Sheet 2 of the Drawings, represents another mode of con-
structing the rani of an hydraulic press for the purpose of imparting to it a
velocity proportionate to the resistance offered by the matters to be compressed.
A is the ram with a central longitudinal hollow B, within which is placed the
fixed stock or stopper C. The stopper is packed water-tight by the collar D,
beyond which the hollow in the ram is increased in diameter, and that portion
of its external periphery is cut away so as to diminish the thickness of the sides
E, E, which take into a groove cut for them in the bottom of the cylinder.
Water is forced in by the pipe G, which, acting against the surface H, H, of
the ram, forces it up until the sides E, E, are withdrawn from them; the water
> will act in addition upon the surfaces I, I, and J, J, and raise up the ram above
the stopper C, when the whole surface thereof will be acted on by the pressure
of the water. By this arrangement three degrees of velocity are obtained by
using one pump, and six degrees by using two pumps. The pipe K, a portion
of which is made of leather or other flexible water-proof material, is fitted with
a valve L, and conducts water into the hollow of the ram A, above the stopper
C, to allow of the descent of the former when the operation is completed. N
is a pipe opening into the lower part of the cylinder, and also furnished with a
valve, to allow the escape of water from the interior as it is compressed by the
descent of the sides E, E, of the ram. Figure 7 is a cross section, and Figure 8

page_text: a longitudinal section, representing the application of a hydraulic press,
constructed according to my Invention to the working of a lever. The object
of this apparatus is to compress the substances to be operated on more rapidly
when it offers less resistance, and consists in a standard A, to the top of which
is hinged the curved lever B. This lever communicates its upward motion to
the plate C by means of the connecting rods D, D, which are loosely riveted to
either side of the cross head I, I, attached to the lever and to the sides of the
plate C; or the rising motion may be communicated by means of a roller to
the plate C which is guided between four uprights E, E, E, E, which are fixed
at top to the underneath of the head place F, and at bottom in the foundation.
The substances to be compressed are placed between the two plates C and F.
Water is forced into the cylinder H in the ordinary manner. The head of the
ram I is furnished with a roller J, having a groove cut on its circumference
into which fits the lever B. The cylinder of the press is mounted upon wheels
to allow of its moving to and fro upon the rails fixed to the floor. The injec-
tion pipo should be made telescopic to allow of this reciprocating motion.
Water is first pumped into the press when it is at the point O, whereby
the ram in its ascent will raise up the lever B, and consequently the plate C.
As the water is pumped in, the press seeks to adapt itself to the curve of the
lever, and therefore slides forward in the direction of the arrow into the
position marked 1 in the Drawing, Figure 8, when the ram has arrived at
one-fourth of its journey; when the ram has reached the half, the press
slides into position 2; when the three-fourths, into position 3; and when the
end, into position 4. It will be seen from what has been said that the ram
began to act with a degree of pressure less than it was capable of applying
direct, on account of its acting on the lever between the fulcrum and the point
whence the pressure is giving off, and that the amount of pressure obtained
gradually increased the further the press travelled from the fulcrum of the lever
until it reached the position 4, when the resulting power was three times the
normal power of the press, because the distance a, b, is three times the distance
a, c. When the operation is completed, the cylinder is emptied in the ordinary
manner, and the ram brought down. The lever, also falling, forces the press
back into the first position O. In order that the hydraulic presses, constructed
according to my Invention, may be expeditiously worked, I recommend that
the inflow and outflow pipes should be constructed of a larger diameter.
Having now described the nature of my said Invention, and in what manner
the same is to be performed, I declare that what I claim as constituting my
said Invention is as follows:-
Firstly, I claim the general arrangement, combination, and adaptation of

page_text: parts described under the first head of this Specification, and represented in
the Drawings, Figures 1, 2, 3, 4, 5, and 6, Sheet 1, for forcing water or
other liquid into the cylinder of a hydraulic press in a continuous stream, and
for effecting the rise of the ram at a diminishing rate of speed with an increas-
ing amount of pressure, according as the substances are compressed.
Second, I claim the arrangement and combination of the conical rollers,
combined with the apparatus, herein-before first claimed, for communicating
the requisite motion from a steam engine or other prime mover to the axis of
the escapeinent wheels, represented in the Drawings, Figures 4 and 4*, Sheet 1,
and before described.
Third, I claim the general arrangement and combination of parts, repro-
sented in Figures 4b, 4°, Sheet 2 of the Drawings, and before described, for
forcing into a hydraulic press water in a continuous stream.
Fourth, I claim the various modes of constructing the rams of hydraulic
presses, as represented in the Drawings, Figures 1, 2, 3, 4, 5, and 6, Sheet 2,
and before described, in order that the ram may rise at a decreasing rate of
speed with an increasing amount of pressure, in proportion as the resistance of
the substances to be operated upon increases.
Fifth, I claim the use of a lever arranged and combined with the ram and
presser plate, as represented in Figures 7 and 8, Sheet 2 of the Drawings,
and before described.
And, sixth, I claim, generally, causing the rams of hydraulic presses to move
at variable rates of speed by means of the arrangements before described, or
by any mere modifications thereof.
In witness whereof, I, the said Baron Louis Lo Presti, have hereunto set
my hand and seal, this Twenty-third day of May, One thousand eight
hundred and fifty
B. LOUIS LO PRESTI. (L.S.)
Signed, sealed, and delivered by Baron Louis
Lo Presti in my presence at Vienna, this
Twenty-third day of May, 1850 (Fifty).
ARTHUR C. MAGENIS, H.M's. Secretary of Embassy.