IMPROVEMENTS IN HYDRAULIC ENGINES, ACCUMULATORS, AND HOISTING APPARATUS
Year: 1875

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane,
in the County of Middlesex, Patent Agent, for the Invention of
"IMPROVEMENTS IN HYDRAULIC ENGINES, ACCUMULATORS, AND HOISTING
APPARATUS."-A communication from abroad by Ferdinand Rochow,
of Brooklyn, in the County of Kings, and Francis Otto Matthiessen,
of New York City, both in the State of New York, United States of
America
.
.COMPLETE SPECIFICATION filed by the said Alexander Melville Olark
at the Office of the Commissioners of Patents, with his Petition
and Declaration, on the 14th May 1875, pursuant to the 9th
Section of the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent, send greeting.
WHEREAS I am in possession of an Invention for "IMPROVEMENTS IN
HYDRAULIC ENGINES, ACCUMULATORS, AND HOISTING APPARATUS," and have

page_text: power accumulated, and thereby preserve the engine from injurious
strain.
With reference to the hoisting apparatus it is the object of the
Invention to produce an hydraulic press with an adjustable valve
mechanism, which will control the admission of power according to the
requirements of the apparatus, that is to say, which will allow the
requisite access of power when the apparatus is to be raised, but will
promptly shut it off when the apparatus is to be lowered. A device is
also to be provided for automatically disconnecting the power when the
apparatus has reached its greatest height.
The Invention as far as it relates to the engine proper consists
principally in providing one or both heads of the main cylinder of the
engine with projecting chambers of smaller diameter, and in providing
one or both faces of the main piston with projecting plungers of a size
to fit said chambers, a separate valve chamber controlling the supply of
liquid to the main piston, while another valve chamber connects with
the projecting chambers to regulate the flow of the liquid which is
acted upon by the smaller plungers. By this arrangement the
smaller plungers moving in the projecting chambers will constitute
pumps for forcing liquid with a degree of pressure greater than that
required to move the large piston. The liquid moving the large piston
will not enter the smaller chambers, the liquid acted upon being in
entirely disconnected channels.
The Invention also consists in providing the valve chamber which
regulates the supply of liquid to the main piston with a valve rod,
carrying a head or piston at one end and a smaller head or piston at the
other end, so it will be automatically effected by hydraulic pressure, such
pressure acting continuously on the smaller head and alternately on
the larger head.
Another distinguishing feature of the Invention in the engine consists
in the provision of enlarged pockets at the ends of the above-mentioned
pressure chamber for the purpose of receiving a gradually disappearing
water cushion which will prevent the occurrence of shocks at the ends of
the strokes of the pressure plungers.
With reference to the accumulator the Invention consists in devising
a chamber into which the liquid used for operating a hoisting, or.other

page_text: apparatus is forced by the pump, and whence it is passed to such
hoisting or other apparatus. This chamber contains a weighted top
plunger connecting with the valve that controls the supply of operating
liquid to the engine or pump. When the pump operates and the
hoisting apparatus is not used the pressure liquid will accumulate in the
weighted chamber and elevate the weight, thereby however also, if this
process continues, shutting the supply valve so as finally to cause the
pump or engine to cease operating. If subsequently the hoisting or
other apparatus is set in motion, the weight of the accumulator will be
utilized in properly supplying the liquid to said apparatus, and by its
descent it will reopen the valve and restart the engine.
With reference to the hoisting apparatus the Invention consists in a
new valve arrangement for the hydraulic press, devised with the special
object of allowing the elevator to be arrested at any suitable height by
the closing of the valves, or to be raised by the opening of one valve, or
lowered by the opening of another valve and the closing of the first.
The Invention also consists in supplying the piston of the hydraulic
press with an attachment, whereby when said piston has reached its
greatest elevation the valves are closed, and further motion is prevented.
The total discharge of the piston from the cylinder of the press is thereby
averted.
"In the accompanying Drawing Figure 1 represents a longitudinal
vertical section of the hydraulic engine, accumulator, and hoisting
apparatus, showing the parts properly connected; Figure 2 is a plan
view of the engine; Figure 3, an end view of the same; Figure 4, a
detail cross section through one of the reduced plunger chambers;
Figure 5, a detail longitudinal section through one end of said chamber;
Figure 6 is a side elevation on a reduced scale, showing the general
disposition of the parts of the Invention; Figure 7 is a vertical transverse
section of the press; Figure 8 is a detail central section through the
valve chamber of the press; Figure 9 is a side view of said valve
chamber; and Figure 10, a sectional elevation of a modified form of the
accumulator. Similar letters of reference indicate corresponding parts in
all the Figures.
With special reference to Figures 1, 2, 3, 4, and 5 the construction of
'the hydraulic engine will first be described. In these Figures the
letter A represents the main cylinder of the engine, B is its reciprocating

page_text: •
piston. From the opposito faces of the piston project parallel with it.
axis two rods C, C³, both of equal diameter, and each much smaller.in
diameter than the piston` B. D and D³ are two cylindrical chambers,
projecting respectively from the heads of the cylinder A, each of a
diameter somewhat larger than that of a rod C, C³, and both situated to
receive the ends of said rods C, C³, respectively as in Figure 1. The
length of each of the chambers D, D³, is such that they will allow the
rods C, C³, to follow the full strokes of the piston B, and still always
contain the ends of said rods. Suitable packing a is applied at the
mouth of each chamber D, D³, around the rods 0, 0%, to prevent the
liquid in the cylinder A. from entering oither of the said chambers, and
vice versa. The rods C, C', constitute the plungers, and the chambers D, D³,
the barrels of the pump or pressure engine which it is intended to
operate.
The principle of the Invention will be readily understood by an
example, as follows:-Suppose the lead of water acting on the piston B
to excrt a pressure of ten pounds to the square inch, and the piston B to
have an area of 100 square inches, the total pressure on the piston wil.
bc 1000 pounds. Now if the area of cross section of each plunger is
only 2 square inches the piston B would be enabled to create hydrostatic
pressure to the amount of 500 pounds per square inch by means of the
plunger C, minus loss by friction. This increase of pressure on a smaller
column of water or other liquid than that required to operate the
piston B is what it is intended to obtain; it is obtained by each
plunger C, C³, and there may be but one such plunger on one face of the
piston, or one on each face, as shown, or more than one on one or both
faces, and a corresponding arrangement of chambers D, &c, for the
reception thereof.
For operating the piston B a valve mechanism has been devised,
which is clearly illustrated in Figure 1, that is to say:-A cylindrical
valve chamber E connects by two ports b and d with the respective ends
of the cylinder A, and is supplied with water through a middle pipe e,
and exhausts through pipes fand g. Within the chamber E is fitted a
rod F parallel to the axis of the cylinder A, and carrying two valves k
and incarer the middle, and pistons ; and 7 at the respective ends.
Each valve and i fits the chamber E like a piston, and the two said
valves are as far apart from cach other as the ports b and d. The
pistou is as large in diameter as the valves and i, but the piston is

page_text: .smaller in diameter, and is surrounded by a. contracted end of the
chamber E, as is clearly shown in Figure 1. Through a small tube ma
constant head of water is conducted into the contracted end of the
chamber E, and pressing against the outer face of the piston 1. The
opposite end of the chamber E connects by a tube n with a small
cylinder o, within which moves a double-headed piston p. A small water
supply pipe q, having the same head as the pipe m, leads into the
cylinder o and supplies the end of the chamber E, and presses against
the larger piston ; as long as the piston p does not interpose one of its
heads, as it is shown to do in Figure 1, between the pipe q and the
tube n.
In the latter position the tube n communicates with a small
discharge tube 1. The position p is moved the short stroke, required to
connect n alternately with 7 and r by lugs 8, s¹, on a rod t that projects
from the piston B, said lugs striking a crank u on the rod of the
piston p. Now if the piston B moves in the direction of the arrow, :
shown in Figure 1, it will at the end of its stroke draw the lug & against
the crank u, and move the piston p so as to establish connection between
the pipe q and the tube n. The water will then press on the pistonj,
and as the diameter of j is larger than that of the piston 7 the pressure
on j will prevail, and push the rod F with all its attachments in the
direction of the arrow 1. This will bring the valve h between the two
ports b, d, and between the port 6 and the supply pipe e, whereas the
valve will be moved beyond the port d, establishing communication
between the pipo e and the port d, and closing the pipe g. The supply
will then enter through d, and move the piston B in the direction of the
arrow 2, the exhaust escaping through the port 6 and thence through f.
At the end of this stroke the lug s' will strike the crank u and move the
piston p, so as to close the pipe q and establish connection between n
and r.
The pressure on the smaller piston 7. will now prevail, there
being none to counteract in the opposite direction, and thus the rod F
with all its appendages will be moved in the direction of the arrow 2
until the valve h closes the discharge f, and establishes communication
from e to b, while the valve i will establish communication from d to g.
The motion of the piston B is thus once more reversed, and the operation
continued as described.
It will be observed from the foregoing that the automatic adjustment

page_text: piston j. The chambers D, D³, communicate respectively with chambers
G and G³, each of which contains a suction valve and a delivery valve
of usual style. A pipe H connects and joins the chambers G, G³,
discharge pipe H' extending to the machine or place destined to receive
the water that is forced by the pressure pumps C, D, and C³, D'; I, I, aro
suction pipes.
In order to prevent the plungers C, C³, and also the rod F from
coming to an abrupt termination of their motions, and creating shocks
injurious to the machinery, the water which they meet at the ends of
their strokes being nearly inelastic, a pocket w is applied for the
reception of every such rod, that is to say, the chambers D, D³, terminate
in such pockets and also the ends of the valve chamber E. Every such
pocket is just large enough in diameter to receive the end of the rod
(C or C³, or F), and has tapering notches cut into its sides, which
notches are deepest at the mouth of each pocket and become. shallower
the nearer they approach the closed end thereof, as is clearly shown in
Figure 5. When the plunger C (for example) enters its pocket wit will
gradually, and in constantly diminishing quantity, displace the water
from within such pocket, the water escaping through the notches until
the plunger closes the notches entirely. The water in the pocket will
thus feebly resist the entry of the plunger into the pocket, and con-
stitute, by virtue of its gradual and slow escape into the body of the
chamber D (or D²; or E), a cushion for gradually diminishing the speed'
of each plunger and preventing injurious shocks.
The pump above described can be used to be acted upon by one kind
of liquid and to act upon another. Overflow or spent water of any kind.
can be used for operating the pump and raising clean water, or forcing
oil or other liquid to an hydraulic press or other apparatus. If oil is
forced by the plungers C, O, much friction will be avoided, and the oil
after it has acted on the hoisting or other apparatus can be drawn back
to the chamber G, losing nearly nothing by evaporation or otherwise.
In other words a continuous conduit for the oil from the chamber G to
the press and back to G can be used, a suitable liquid for operating the
engine being meanwhile employed.
"
The accumulator and hydraulic press will now be described, with
special reference to Figures 1, 6, 7, 8, 9, and 10. In these Figures the
letter J represents the improved accumulator carrying a chamber 6*,
through which the water or other fluid operating the engine passes to

page_text: the same, and constituting in itself a chamber f*, through which the
liquid that is forced from said engine towards the hoisting apparatus is
caused to pass. The water, steam, or other fluid fed to the engine passes
from the pipe a* into the chamber 6* of the accumulator, and thence
through the pipe d*, which branches into the pipes m, e, and q, to the
engine, working the same in the manner above described; or if a different
engine be substituted the water, steam, or other motor employed passes
to such engine by the passage a*, b, d. The liquid which is forced
from the engine to operate the hoisting apparatus enters by the pipe H¹
the chamber f* of the accumulator and passes from f* through the:
pipe g* to the hydraulic press. There may be two or more hoisting
apparatus in the same building in which the accumulator is placed, in
which case all the pipes 9* that lead to the several hydraulic presses
connect with the chamber f* of the one single accumulator, substantially
as indicated in Figure 1. A weighted plunger L fits tightly into the
upper part of the chamber f* and supports a sleeve M that constitues a
balanced valve working in the chamber 6*. When the pump or other
hydraulic engine is operating, and the lifting apparatus is not used, it is
clear that the pressure liquid supplied by the pump will accumulate in
the chamber f, and will gradually raise the weighted plunger L until
finally it will, by means of said plunger L, raise the valve M into a
position in which the same will shut off all communication between the
openings or passages a* and d*. Then, that is, by such elevation of the
valve-M, the supply of water or other fluid to the pump will be shut off;
and the pump will necessarily cease to operate. When thereupon the
hoisting apparatus is used it will draw its supply of liquid from the
accumulating chamber fx, and cause the weighted plunger L to
gradually descend, said plunger applying its pressure and weight in aid
of the operation of the hoisting apparatus until by its descent it will
gradually withdraw the valve M from the mouth of the pipe d*, and
thereby allow the pump to be fed again with the water or other fluid
which moves it.
3-
Having thus described the accumulator it is now intended to describe
the hydraulic press with which it is connected, said press being a
cylindrical vessel N placed in an upright or other suitable position, and

page_text: upper part and outer side of the cylindor N; in this chamber are
arranged two valves * and i*, both self closing upon their seats, the
valve * being interposed between the passage of the pipe 9* and the
entry j* for the liquid into the cylinder N, while the valve i* is inter-
posed between such communicating opening j* and the final discharge
pipe *, through which the liquid that has operated the press escapes;
two lifting pins m* and n* are arranged respectively benoath the valves h*
and **, and connected with eccentrics or cranks o*, p*, that are mounteḍ
upon a crank shaft R. The eccentrics on said crank shaft are so set, as
indicated in Figure 9, that only one of the pins m*, n*, can be raised at
ono time, so that if the shaft R is turned in one direction it will lift the
pin m*, whereas if turned in the other direction it will lift the pin n*.
When the valve h* is on its seat, as in Figure 8, the pressure liquid
entering through the pipe g* cannot reach the cylinder N. When it is
intended to raise the plunger O the shaft R is turned by hand otherwise
so that it will by the eccentric o* and pin m* raise the valve h* off its
seat, whereby communication is established between the pipe 9* and the
cylinder N. The plunger O is now raised by the pressure liquid which
enters the cylinder N. Meanwhile the pressure of the liquid entering
the cylinder N keeps the valve i* on its seat. When it is desired to
arrest the plunger o at any position the shaft R is turned back to lower
the valve h* upon its seat, and the pressure liquid then serves to hold
the valve h* on its seat and prevent the further entrance of liquid into
the cylinder N, while at the same time the exit of liquid from the
cylinder is prevented by the valve i*. When the valve i* is raised by a
corresponding motion of the shaft R the weight of the plunger o will
gradually force the liquid out of the cylinder N through the channel jr
and pipe *. Thus it is that when the plunger o is connected with the
rope or cable S of a hoisting apparatus, in the manner indicated in
Figure 6, its ascent and descent will cause a corresponding elevation and
lowering of the hoisting platform T, and the operation and position of
the platform can be controlled by a hand line or rope connected with a
crank of the shaft R, which line or rope when pulled by the operator
standing on the platform T will either serve to raise the valve h* or tho
valve *, or to hold both valves down, according to the position or move-
-ment which it is desired to impart to the platform. For purposes of
greater safety a rod * should be attached to the crank shaft R, and the
same provided with a projecting shoulder or stop 8* at its upper portion,
and a sleeve t that projects from the frame should be connected with

page_text: the plunger o to embrace said rod *, so that when said sleeve at the
highest necessary position of the platform T strikes the stop ** it will
cause the crank shaft R to be turned in a way that will lower the pin m*
and valve k*, thus preventing the further ascent of the plunger o and its
final discharge from the cylinder N.
bearings pro-
S
The plunger o carries at its upper end a framework, in which are hung
two loose pulleys u* and **, or a larger number if desired. These
pulleys are raised and lowered with and by the plunger o. The hoisting
rope S has one end attached to a shaft U, that hangs in
jecting from the cylinder N or other suitable framework. The rope
passes from the shaft U over the loose pulley u*, then down on the other
side of the cylinder N, around a loose pulley w*, back again from w*
over the pulley *, thence downwards around a loose pulley x* that is
hung on the shaft U, and up to the top of the building around pulleys y*,
from which the hoisting platform T is finally suspended. By this arrange-
ment of the loose pulleys u*, v*, w*, x*, the motion of the plunger o
can be utilized for an increase of motion of the platform T, more rapid
motion of T being obtained by an additional number of loose pulleys on
the shaft U and on the plunger frame, etc.
With reference to the pipe 9* and its connection with the accumulator
it will be observed that when a series of such pipes 9* are connected with
said accumulator an equal number of hydraulic presses and elevators may
be operated from the same pump or engine, and still the pump or engine
will not be worked to excess, because unless all the elevators are operated
. at the same time in the same direction the pump will only work on a
portion of them, and if a larger number of elevators be raised at once
.the pump or engine, together with the weight of the raised plunger L,
will be sufficient to supply them all with the requisite power for a limited
period. The accumulator will be recharged whenever the elevators
descend.
The accumulator represented in Figure 10 is substantially like that
shown in Figure 1, excepting that in it a weighted lever W is interposed
between the plunger L and valve M, connecting with the same by suit-
able links. This will dispense with the necessity of much dead weight,
which must be used under the arrangement shown in Figure 1, and
yield nevertheless as beneficial results,
:

page_text: Having described the nature of the Invention and the manner of per-
forming the same, I declare that what I claim as new and desire to
secure by Letters Patent is,―
:
First. The main cylinder A, having the projecting chamber D or
chambers D and D formed on its head or heads combined with the
piston B, which carries the plunger C or plungers C and C³, and with the
chamber G, having a section and a delivery valve, and with the pipes H
and I that lead into the chamber G, the plunger and chamber D being
of a smaller diameter than the piston B, for producing hydrostatic
pressure on a liquid supply which does not enter the cylinder A, substan-
tially as specified.
Second. The valve rod F, carrying the larger piston j at one end and
the smaller piston at the other end, to be affected automatically by con-
tinuous hydraulic pressure on the smaller piston and alternately pressure
on the larger piston, substantially as specified.
Third. The reciprocating piston p, placed within the cylinder o and
combined with the supply pipe q, tubes n and r, and chamber E, substan-
tially as and for the purpose herein shown and described.
Fourth. The pocket w arranged at the end of an hydraulic chamber
for the reception of a plunger moving in said chamber and provided with
notches, substantially as set forth.
Fifth. The accumulator J, containing the weighted plunger L and
balanced valve M, the plunger L entering the chamber f* that connects
with the pipe H' and pipes g*, g*, while the valve M when raised closes
the passago d*, substantially as and for the purpose specified.
Sixth. In combination with a hydraulic press the valve chamber P,
containing the valves h*, **, and connected with the pipes 9* and * and
opening j*, substantially as specified, the valves *, **, being arranged
above lifting pins m*, n*, as and for the purpose set forth.
Seventh. The combination of the crank shaft R carrying eccentrics o*
and p* with the lifting pins m*, n*, valves h*, i*, and with the cylinder N
of a hydraulic press, substantially as set forth.
-
Eighth. The rod * carrying the stops and connected with the crank
shaft R that controls the valves *, i*, in combination with a sleeve or
projection t on the reciprocating frame on the hydraulic plunger o, sub-
stantially as herein shown and described.

page_text: Ninth. The hydraulic plunger E, carrying the loose pulleys **, *,
and combined with the loose pulleys x*, w*, that are hung in stationary
framework, substantially as and for the purpose specified.
.In witness whereof, I, the said Alexander Melville Clark, havo
hereunto set my hand and seal, this Fourteenth day of May, in 5
the year of our Lord.One thousand eight hundred and seventy-
five.