of and Apparatus for Automatically Regulating the Supply of Water Under Pressure to Hydraulic Machinery and Motors.
Year: 1898

page_text: Date of Application, 2nd May, 1898
Complete Specification Left, 18th Jan., 1899-Accepted, 18th Feb., 1899
PROVISIONAL SPECIFICATION.
Method of and Apparatus for Automatically Regulating the Supply
of Water Under Pressure to Hydraulic Machinery and Motors.
I, LOUIS LACOIN, of 18, Rue Mogador, Paris, France, Engineer, do hereby
declare the nature of this invention to be as follows:-
All apparatus in which water under pressure is employed as means of trans-
mitting or producing power, such as hydraulic motors, hydraulic presses, cranes,
lifts, and the like, suffer from the same inconvenience, namely, that they are
constructed for producing a certain maximum effort by means of water having a
determined pressure, and when the resistance which they have to overcome is
less than that effort, there is only one method of preventing damage to the
machine, namely, to throttle the water pressure supply, resulting in a loss of
pressure which reduces the pressure behind the hydraulic piston to the required
amount, but involves nevertheless the same expenditure of water under pressure,
so that there is a loss of energy which may be considerable.
For reducing this loss, recourse has been had to arrangements that only serve
as a makeshift; they consist generally in the employment of several pistons that
act either separately or simultaneously.
According to my present invention I obviate the above disadvantage as
follows:
I combine an apparatus supplying a constant and regulatable quantity of water
with a pressure variable in proportion to the load supported, but always less than
the pressure of the body of water under pressure, while using only a quantity
of such water proportional to the work required to be done, the balance of the
water required being supplied by the autoniatic introduction of water at low pres-
sure or even without pressure.
This apparatus has in part a certain analogy to the hydraulic ram; but it
differs from this in that I endeavour to obtain a supply which shall be uniform
notwithstanding the variations of pressure and which can be varied at will, and
that the water pressure supplied by the apparatus is less than, instead of greater
than, that supplied to the apparatus.
For this purpose I arrange on the supply pipe for the pressure water a partially
balanced check valve, closed by the pressure.
Beyond this valve is, firstly, a passage leading to the underside of a heavy
piston working in a cylinder, the weight of which piston tends to open the valve
against the pressure in the supply pipe, through the medium of springs,
secondly, a branch passage leading on the one hand to the upper side of the
heavy piston, in which passage is a throttle valve, and on the other hand, to the
valve apparatus which controls the supply of pressure water to the hydraulic
apparatus to be worked. On the passage leading from the underside of the
heavy piston to the throttle valve is a branch passage provided with a check valve
and leading to a low pressure water supply. When the apparatus is not operat-
ing the heavy piston forces the balanced check valve on the high pressure supply
open, so that water pressure passes through the several above named passages

page_text: above and below the heavy piston, and also to the casing containing the distri
buting valve apparatus.
As soon as this is opened to admit water pressure to the hydraulic press &c.,
the water pressure will flow through the balanced check valve to below the piston,
thence through the throttle valve to the top of the piston and also to the dis-
tributing valve apparatus.
If the throttle valve is set to admit the maximum water pressure to the
hydraulic press to overcome a maximum resistance therein while flowing at a
slow speed, then no regulating action of the apparatus will take place; if how-
ever, the resistance to be overcome by the press is below the maximum, then
there will be a correspondingly accelerated How of the pressure water through
the passages and valves.
In passing through the throttle valve at this accelerated speed, the water will
there be subject to a certain reduction of pressure beyond the valve, due to the
throttling action, which will result in a corresponding reduction of pressure
above the heavy piston, which will consequently be raised somewhat by the
greater pressure below. By such raising of the piston the supply check valve
will be relieved of its downward pressure, and it will consequently, be suddenly
closed by the upward pressure of the high pressure water supply.
Hereupon, as the body of water contained in the passages leading from the
closed supply valve to the distributing valve apparatus (which passages are made
of some length to afford a considerable body of water in them) will, by reason of
its inertia, still move forward with a certain speed, a partial vacuum or suction
will be produced in the passage near the supply valve, in consequence of which
the check valve on the low pressure supply branch, which is there situated,
will be opened, and a quantity of low pressure water will be drawn
in behind the moving body of high pressure water. Meanwhile, the
high pressure supply being cut off, the upward pressure on the piston will
be decreased, and the piston in descending again, will force open the supply
valve, a fresh high pressure supply will take place automatically closing the low
pressure supply, and, if the resistance of the press is still below the maximum,
the resulting accelerated speed of the high pressure water will cause the above
described action to be repeated one or more times, until by the increasing resistance
of the press, the flow of the pressure water is too slow to produce any farther
throttling.
For preventing detrimental concussions due to the sudden stoppages of the
high pressure supply, I provide air vessels both upon the supply passage and on
the passage leading from the throttle valve to the distributing valve apparatus.
In some cases I prefer to connect the hand lever operating the distributing
valve gear to the spindle of the throttling valve by means of suitable gearing,
whereby, the throttle valve being more or less completely closed at starting, the
distributing valve is first completely opened, after which the throttle valve is
gradually opened to admit the full high pressure by degrees.
Dated this 2nd day of Max 1898.
ABEL & IMRAY,
Agents for the Applicant.
Method of and Apparatus for Automatically Regulating the Supply
of Water Under Pressure to Hydraulic Machinery and Motors.
I, LOUIS LACOIN, of 18, Rue Mogador, Paris, France, Engineer, do hereby
declare the nature of this invention and in what manner the same is to be per-

page_text: formed, to be particularly described and ascertained in and by the following
statement:
All apparatus in which water under pressure is employed as means of trans-
mitting or producing power, such as hydraulic motors, hydraulic presses, cranes,
lifts, and the like, suffer from the same inconvenience, namely, that they are
constructed for producing a certain maximum effort by means of water having a
determined pressure, and when the resistance which they have to overcome is
less than that effort, there is only one method of preventing damage to the
machine, namely to throttle the water pressure supply, resulting in a loss of
pressure which reduces the pressure behind the hydraulic piston to the required
amount, but involves nevertheless the same expenditure of water under pressure,
so that there is a loss of energy which may be considerable.
For reducing this loss, recourse has been had to arrangements that only serve
as a makeshift; they consist generally in the employment of several pistons that
act either separately or simultaneously.
According to my present invention I obviate the above disadvantage as
follows:-
I employ an apparatus so arranged as to supply a constant and regulatable
quantity of water with a pressure which is variable in proportion to the work
performed but always less than the pressure of the supply of pressure water,
only a quantity of such water proportional to the work required to be done being
expended while the balance of the water required is supplied by the automatic
introduction of water at low pressure or even without pressure.
This apparatus has in part a certain analogy to the hydraulic ram; but it
differs from this in that I endeavour to obtain a supply which shall be uniform
notwithstanding the variations of pressure and which can be varied at will, aud
that the water pressure supplied by the apparatus is less than, instead of greater
than, that supplied to the apparatus.
For this purpose I arrange on the supply pipe for the pressure water a partially
balanced check valve, closed by the pressure.
Beyond this valve is, firstly, a passage leading to the underside of a heavy
piston working in a cylinder, the weight of which piston tends to open the valve
against the pressure in the supply pipe, through the medium of springs,
secondly, a branch passage leading on the one hand to the upper side of the
heavy piston, in which passage is a throttle valve, and on the other hand, to the
valve apparatus which controls the supply of pressure water to the hydraulic
apparatus to be worked. On the passage leading from the underside of the
heavy piston to the throttle valve is a branch passage provided with a check valve
and leading to a low pressure water supply. When the apparatus is not operat-
ing the heavy piston forces the balanced check valve on the high pressure supply
open, so that water pressure passes through the several above named passages
above and below the heavy piston, and also to the casing containing the distri-
buting valve apparatus.
As soon as this is opened to admit water pressure to the hydraulic press &c.,
the water pressure will flow through the balanced check valve to below the piston,
thence through the throttle valve to the top of the piston and also to the dis-
tributing valve apparatus.
If the throttle valve is set to admit the maximum water pressure to the
hydraulic press to overcome a maximum resistance therein while flowing at a
slow speed, then no regulating action of the apparatus will take place; if how-
ever, the resistance to be overcome by the press is below the maximum then
there will be a correspondingly accelerated flow of the pressure water through
the passages and valves.
In passing through the throttle valve at this accelerated speed, the water will
there be subject to a certain reduction of pressure beyond the valve, due to the
throttling action, which will result in a corresponding reduction of pressure
above the heavy piston, which will consequently be raised somewhat by the

page_text: greater pressure below. By such raising of the piston the supply check valve
will be relieved of its downward pressure, and it will consequently be suddenly
closed by the upward pressure of the high pressure water supply.
Hereupon, as the body of water contained in the passages leading from the
closed supply valve to the distributing valve apparatus (which passages are made
of some length to afford a considerable body of water in them) will, by reason of
its inertia, still move forward with a certain speed, a partial vacuum or suction
will be produced in the passage near the supply valve, in consequence of which
the check valve on the low pressure supply branch, which is there situated,
will be opened, and a quantity of low pressure water will be drawn in behind
the moving body of high pressure water.
I will proceed to describe the said apparatus and method of operating in con-
nection with the accompanying drawing, in which Fig. 1 shews a vertical section
of part of the same, Fig. 2 a diagrammatic elevation of the entire apparatus to
a smaller scale, Figs. 3 and 4 an elevation and plan of an arrangement of the
apparatus as applied to the working of a hydraulic press.
The apparatus consists of a valve B partially in equilibrium, a heavy piston H
acting on spindle T of valve B through springs K and L which piston rises
when the difference of pressure to which it is subject on its upper and underside
attains a certain value, a rotary throttling slide C for controlling the water
supply, a valve D for admission of the low pressure water supply, a conduit
pipe G leading to the machine worked by hydraulic pressure, and lastly, two air
vessels I and J, Fig. 2, which serve to limit the repeated variations of speed
in the operating column of water. M is an ordinary distributing device for
supplying the working machine. Q is the discharge pipe for the waste water,
which generally forms the supply of low pressure water conveyed through pipe F.
The apparatus operates as follows:-
The pressure water is supplied through E and passes through valve B under-
neath the piston H whence, it passes through the regulating valve C and
through channel N to the space above piston H, and into the conduit pipe G
leading it to the air vessel J. Thence it passes through pipe to the distri-
butor M, and pipe P leading it to the apparatus where it is to be utilised.
If the resistance to be overcome by the latter is less than the maximum power
for which the apparatus is arranged, the velocity of the water flowing through
the latter tends to increase, and if the opening of the throttle valve C is suitably
adjusted, there will be produced when the velocity has attained a certain point,
a diminution of pressure on the upper side of the valve C and piston H, as
compared with the pressure below these parts, so that the piston H will conse-
quently be raised by the pressure on its underside. The springs K and L under
the piston have their tension so arranged that they keep the valve B in the open
position until the piston H has risen to a certain extent, when the spring L,
being relieved of a certain amount of the downward pressure of spring K will
effect the rapid closing of the valve B.
By this means an action like that of a hydraulic ram will be produced in the
water in pipe E, which however is expended by compressing the air in air
vessel I. At the same time the water in the pipe G, having attained a certain
momentum does not come to a sudden standstill and in thereby producing a
certain suction behind it, it will cause low pressure water to be drawn in through
pipe F and valve 1, which water will consequently flow together with the high
pressure water into the press or other working apparatus.
As long as the velocity of the water does not sink below a certain value the
reduction of pressure at C will be sufficient to keep the piston H in the raised
position and valve B closed. When the said velocity decreases, H will descend
and will cause the springs K L to open the valve B again, so that high pressure
water again enters, thereby increasing the velocity again, and eventually causing
a repetition of the above described action.
In certain cases it will not be necessary to actuate the throttling valve C,

page_text: when once set to the position required, but in other cases it will be of advantage
to connect the levers R and S actuating respectively the valve C and the dis-
tributing valve M in such manner that the latter is first fully opened before the
valve C is acted upon the latter being then gradually opened to the required
throttling position for obtaining the velocity of water desired.
In cutting off the water supply to the working machine, the valve C is first
closed and then the distributing valve M.
Figs. 3 and 4 shew by way of example one arrangement for producing the
above described action.
The hand wheel R S turns the segment wheel X, which can only perform
one revolution during the first half of which it gears with toothed segment Z
while during the other half it gears with the segment Y; this is connected
by a rod t to an arm on the axis of the throttling valve C, while Z actuates the
distributing valve M.
In the position shewn at Figs. 3 and 4, X has fully opened the distributing
valve by turning %, and in continuing to turn in the direction of the arrow, it
gradually opens the throttling valve in acting on Y. When turning X in the
contrary direction C is first gradually closed and the distributing valve Mis
then also closed.
It will thus be seen that by the above described invention a diminished
hydraulic power is supplied to the working machine without loss of useful
effect, solely by diminishing the quantity of high pressure water consumed
and supplying a quantity of low pressure water in lieu thereof.
Having now particularly described and ascertained the nature of this inven
tion and in what manner the same is to be performed, 1 declare that what I
claim is:-
-
1. In apparatus worked by hydraulic pressure the method of automatically
regulating the supply of pressure water in proportion to the work to be performed,
by causing an increase of velocity in the pressure water beyond the normal conse-
quent upon a decrease of work to be performed below the normal to produce a
reduction of pressure upon a device that keeps the supply valve open, so thas
the supply of water pressure is thereby cut off while at the same time a suction
is produced whereby supply of low pressure water is drawn in to take the place
of the pressure water cut off, substantially as described.
2. Apparatus for automatically regulating the supply of pressure water to
machines worked by hydraulic pressure, in proportion to the work to be per-
formed, consisting of the combination of a heavy piston such as H which con-
trols an admission valve such as B for the pressure water, a throttling valve
such as C interposed between the upper surface of such piston and the supply
of pressure water, which has free access to the underside of the piston, a con-
duit pipe such as G leading from the spaces above the throttling valve C and
upper side of the piston H and a branch pipe F with valve I learling from the
under side of valve O to a low pressure water supply, the said parts being
arranged and operating substantially as and for the purposes herein described.
3. Apparatus for automatically regulating the supply of pressure water to
machines worked by hydraulic pressure, combined and operating as herein
described with reference to the drawings.
nated this 18th dor of January 1800