Improvements in Pumps for Liquid or Gaseous Bodies and for various uses.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in Pumps for Liquid or Gaseous Bodies and for
various uses.
I, JEAN NÉPOMUCÈNE HochgesanD, of 200, Quai Jemmapes, Paris, in the Republic
of France, Engineer, do hereby declare the nature of this invention to be as
follows:-
The present invention has for its object an arrangement of single valve pump
reduced to the parts strictly necessary to ensure an absolutely regular delivery, at
the same time obviating all injurious spaces and all loss due to the more or less
uncertain working of the valves and particularly of the suction valve.
This arrangement of pump enables all liquid or gaseous bodies, such as water,
petroleum, oil, air, etc., to be distributed in exactly determined quantity, capable of
being regulated at will and automatically by the action of a float or other regulating
appliance, according to whether it is used for the automatic feeding of boilers or for
the distribution of petroleum or of spirit of petroleum in oil motors; my arrangement
of pump may also be applied to the distribution of oil for the lubrication of engines
and machines of all kinds, or as pneumatic pump, as air compressor for inflating
pneumatic tyres, or as vacuum pump, etc.
My arrangement of pump consists essentially of a piston which moves in the
interior of a movable cylinder open at its lower part and moved during a part of the
stroke of the piston by the frictional action of the packing of the latter,
and of a fixed seat on which the bottom of the cylinder is seated during the
delivery period, this seat being provided with a passage fitted with escape
valve.
On the rising of the piston the cylinder, following the movement of the latter, is
separated from its seat so that there is communication between the exterior and
interior of the cylinder and consequently suction to the interior of the latter; on
the contrary, on the descent of the piston the cylinder, following anew the movement
of the piston, becomes seated on its seat so as to close all communication between
the exterior and the interior, and the fluid sucked in is forced into the delivery
passage.
The working of my arrangement of pump may therefore be divided into four
times :-
1. Ascent of the cylinder and piston to establish communication between the
exterior and the interior of the cylinder.
2. Ascent of the piston alone or suction to the interior of the cylinder.
3. Descent of the cylinder and piston or application of the cylinder to its seat, so
as to close all communication between the exterior and interior of the cylinder.
4. Descent of the piston alone or delivery of the fluid sucked in.
In order that the invention may be more clearly understood, I have represented
examples of the same in the accompanying drawings.
Fig. 1 is a vertical section showing the general arrangement of my improved pump
provided with a method of mechanical driving.

page_text: Figs. 2, 3, 4 are vertical sections showing the different phases of operation of my
arrangement of pump.
Fig. 5 represents a modification in the mode of driving the piston rod.
Figs. 6, 7, 8, 9 are vertical sections showing the different phases of operation of a
modification of my arrangement of pump applied to a constant delivery apparatus.
Fig. 10 is a horizontal section drawn on the line 1-2 of Fig. 6.
Fig. 11 represents another application of my arrangement of pump.
In the various figures like letters indicate like parts.
As shown at Fig. 1 my arrangement of pump consists essentially of a piston a
provided with suitable packing to render it tight with a movable cylinder 6 provided
with an opening at its lower part, in which cylinder the piston a moves, and with a
fixed seat c upon which the cylinder b rests during the period of delivery, and com-
prising a delivery passage d with escape valve e.
The piston may receive its to and fro motion by any suitable mechanical con-
trivance; in the example represented at Fig. 1 the piston rod receives its to and fro
motion from a link driven by an eccentric receiving its rotary motion from a
toothed or worm wheel gearing with an endless screw upon the axle of which is
mounted a grooved pulley or other driving arrangement.
The piston a, in moving upwards,' carries with it, during part of its stroke,
consequent on the friction of its packing, the cylinder b, until this latter eomes
against a stop piece, for example a sleeve f screwed into the upper part of the
container g and fixed in its regulated position by a lever lock-nut h.
The apparatus being in the position shown by Fig. 2, the orifice i, formed in the
lower part of the cylinder b, opens directly into the interior of the container g,
so that the piston, in its upward motion to the position shown at Fig. 3, sucks
into the interior of the cylinder b, the fluid contained in the container g.
As soon as the piston commences to descend, it carries with it, consequent on the
friction of its packing, the cylinder b, and applies it to its fixed seat c, see Fig. 4, so
as to prevent all communication between the interior of the cylinder b and the
interior of the container g, and to cause the orifice i to open into the delivery
passage d formed in the seat c.
The piston continuing its descent, drives into the passage d, all the fluid which
had been sucked into the cylinder b; the fluid thus driven, in order to escape, pushes
back the valve e, which again closes automatically by the action of its spring, when
the delivery action is finished.
In consequence of the possibility of regulating the position of the sleeve f, the
useful suction stroke of the piston can be varied at will and a variable delivery obtained
ranging from zero to a maximum delivery corresponding with the complete stroke of
the piston minus a certain fraction determined by the necessary rise of the cylinder b
to permit suction through the orifice i.
The variation of the delivery of my arrangement of pump can be regulated
automatically; the part serving as stop to the cylinder b is in that case movable and
is operated in any suitable manner, either by the governor of the engine when it is
applied to oil or spirit engines, or by the lever of a float when it is applied to a boiler
feed apparatus; in order to obviate the reaction of the push of the cylinder, an
eccentric will be preferably employed as intermediary for the transmission of the
motion, and as the motion of the stop piece should be effected before it is in contact
with the cylinder, the power which this motion will necessitate will in all cases be
very small and easy to operate even at a distance.
If a certain number of pumps thus constructed are grouped together, several
points can be simultaneously fed at the same time; the apparatus for regulating the
stops could then be mounted on the same part, which, by an easy motion, will permit
of stopping or of again putting in action the entire series of pumps, without dis-
arranging their delivery, and further, of increasing simultaneously the delivery of all
the pumps, at the same time preserving the power of returning to the normal point of
delivery.

page_text: The upward motion of the piston can also be obtained as shown at Fig. 5, by a
cam acting on a lever jointed to the piston rod a, and the delivery be effected
either by a spring or, as represented in the drawing, by the action of a fluid under
pressure (steam, air, etc.) constantly acting within an auxilliary cylinder upon a piston
mounted at the end of the piston rod a of the pump.
Figs. 6 to 10 show the application of my arrangement of pump to a constant
delivery apparatus.
In this example the cylinder b is guided by a disc f, which also serves as a stop to
limit the motion of this cylinder b to the amount required to uncover its suction
orifice when the cylinder is moved by friction of the piston a.
This disc f has around its inner periphery, notches j for the passage of the liquid.
The piston rod, which is terminated by a knob k, passes through a valve / preferably
of spherical form held against the interior rim of the container g by the action of a
spring pressing at one end against the piston a, and at the other against the inner
face of the valve l.
In this apparatus the upward motion of the piston is effected by hand, whilst the
downward or delivery action is effected by the force only of the spring m, which is
compressed in the rise of the piston, but the general operation of the apparatus is
the same as in the previous example.
When the piston rod a commences to rise, (the apparatus being in the position
shown at Fig. 6) the piston moves the cylinder b until this latter is stopped by the
disc f, as shown at Fig. 7; the cylinder 6 then communicates, by its orifice i, with
the interior of the container g; on the further rise of the piston a, this latter sucks
in, through the orifice i, a determined quantity of the liquid contained in the con-
tainer g, see Fig. 8; then, as soon as the knob k is released, the piston, which is
driven downwards by the action of the spring m, commences by moving the cylinder b
down on to its fixed seat c, see Fig. 9, and drives the liquid which was previously
sucked in into the delivery passage, as previously described.
To fill the container g it is only necessary to push the valve / down; in order that
this may be held down, the sleeve of this valve is provided with a screw, the point n
of which slides in a groove o formed in the piston rod and terminating in a circular
groove, enabling the whole of the valve and its sleeve to be turned upon the piston
rod, so that the screw point n, when engaged in this latter groove, prevents the valve
from again closing by the action of the spring m. To reclose the valve it is only
necessary to turn it slightly until the screw point n has arrived in front of the
groove o, so that this valve inay again rise by the action of the spring m, which keeps
it applied against the inner edge of the container g, and thus secures hermetic
closure.
As in this apparatus the upward motion of the piston for suction is effected by
hand, whilst the delivery is operated by the power of the spring only, it is clear that
the pressure of delivery will be always proportional to the power of the spring; there-
fore if any suitable mechanical movement is adopted, by lever, cam, or other suitable
appliance, to effect the upward motion of the piston, that is to say, the suction, an
automatic apparatus of variable pressure will be obtained by varying the tension of
the spring by any convenient means; besides, the speed of descent of the piston, that is
to say, the delivery, will depend on the consumption of liquid effected in the delivery
passage; for example, by applying my arrangement to a lubricating apparatus of
multiple distribution, the quantity of oil delivered will be in proportion to the
number of points lubricated and to the delivery given to each of them. Therefore,
supposing the maximum delivery of the pump to be equal to that necessary for the
maxima feed of all the points, the descent of the piston will only be partially effected
for all deliveries below this maximum, and therefore the suction will no longer take
place, except in a certain proportion dependent on the quantity of oil used, which will
be regulable for each point by means of a screw or needle valve or other arrangement
for varying the flow.
This individual regulation being effected for each point, this delivery can therefore

page_text: be modified, and that simultaneously for all the points, by the simple variation of the
tension of the spring by a screw or other regulation, as above described.
The upward motion of the piston can be obtained on the contrary by the action of
a spring, and the delivery motion be effected by hand, as is shown by the modification
represented at Fig. 11.
In this modification, in the state of rest, the movable cylinder b and the piston a
will, by the action of the spring m, abut against the stop ring f; the apparatus will
thus be always ready to deliver the liquid which has been sucked up by the upward
motion of the piston caused by the action of the spring.
It will be understood that my arrangement of pump may be varied in form and
dimensions and that the arrangements of details may also be modified without
departing from my invention.
Dated this 17th day of December 1898
HARRIS & MILLS,
23, Southampton Buildings, London, W. C., Agents.
Improvements in Pumps for Liquid or Gaseous Bodies and for
various uses.
I, JEAN NEPOMUCÈNE HOCHGESAND, of 200, Quai Jemmapes, Paris, in the Republic
of France, Engineer, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
The present invention has for its object an arrangement of single value pump
reduced to the parts strictly necessary to ensure au absolutely regular delivery, at
the same time obviating all injurious spaces and all loss due to the more or less
uncertain working of the valves and particularly of the suction valve.
This arrangement of pump enables all liquid, or gaseous bodies such as water,
petroleum, oil, air &c. to be distributed in exactly determined quantity, capable of
being regulated at will and automatically by the action of a float or other regulating
appliance according to whether it is used for the automatic feeding of boilers or for
the distribution of petroleum or of spirit of petroleum in oil motors; my arrange-
ment of pump may also be applied to the distribution of oil for the lubrication of
engines and machines of all kinds, or as pneumatic pump, as air compressor for
inflating pneumatic tyes or as vacuum pump etc.
My arrangement of pump consists essentially of a piston which moves in the
interior of a movable cylinder, open at its lower part and moved during a
part of the stroke of the piston by the frictional action of the packing of the latter,
and of a fixed seat, on which the bottom of the cylinder is seated during the delivery
period, this seat being provided with a passage fitted with escape valve.
On the rising of the piston, the cylinder following the movement of the latter, is
separated from its seat, so that there is communication between the exterior and
interior of the cylinder and, consequently suction to the interior of the latter; on
the contrary, on the descent of the piston, the cylinder, following anew the move-
ment of the piston becomes seated on its seat, so as to close all communication
between the exterior and the interior and the fluid sucked in is forced into the delivery
passage.
The working of my arrangement of pump may therefore be divided into four
periods:
1. Ascent of the cylinder and piston to establish communication between the
exterior and the interior of the cylinder.

page_text: 2. Ascent of the piston alone or suction to the interior of the cylinder.
3. Descent of the cylinder and piston or application of the cylinder to its
seat, so as to close all communication between the exterior and the interior of the
cylinder.
4. Descent of the piston alone or delivery of the fluid sucked in.
In order that the invention may be more clearly understood I have represented
examples of the same in the drawings accompanying my Provisional Specification and
in the accompanying drawings.
Fig. 1 is a vertical section showing the general arrangement of my improved pump
provided with a method of mechanical driving.
Figures 2, 3, 4 are vertical sections showing the different phases of operation of my
arrangement of pump.
Figure 5 represents a modification in the mode of driving the piston rod.
Figures 6, 7, 8, 9 are vertical sections showing the different phases of operation
of a modification of my arrangement of pump applied to a constant delivery
apparatus.
Fig. 10 is a horizontal section drawn on the line 1-2 of Fig. 6.
Fig. 11 represents another application of my arrangement of pump.
Fig. 12 is a vertical sectional view of a modification showing it in a position of
rest.
Fig. 13 is a vertical section drawn on the line A-B of Fig. 12.
Fig. 14 is a horizontal section drawn on the line C-D of Fig. 12.
Fig. 15 shows the apparatus at the end of the first phase of the upward stroke of
the piston, that is to say, when the liquid admission orifice is entirely uncovered.
Fig. 16 is a horizontal section drawn on the line E-F of Fig. 15.
Fig. 17 shows the piston at the end of its upward stroke.
Fig. 18 represents the apparatus at the end of the first phase of the downward
stroke of the piston, that is to say when the liquid admission orifice is closed.
Fig. 19 shows the apparatus regulated so as to produce no useful effect.
In the various figures like letters indicate like parts.
As shown at Fig. 1 my arrangement of pump consists essentially of a piston a
provided with suitable packing to render it tight with a movable cylinder 6 provided
with an opening at its lower part in which cylinder the piston a moves, and with a
fixed seat c upon which the cylinder b rests during the period of delivery, and
comprising a delivery passage d with escape valve e.
The piston may receive its to and fro motion by any suitable mechanical
contrivance, in the example represented at Fig. 1, the piston rod receives its to and
fro motion from a link driven by an eccentric receiving its rotary motion from a
toothed or worm wheel gearing with an endless screw, upon the axle of which is
mounted a grooved pulley or other driving arrangement.
The piston a in moving upwards carries with it during part of its stroke,
consequent on the friction of its packing, the cylinder b until this latter comes against
a stop piece, for example a sleeve f, serewed into the upper part of the container g
and fixed in its regulated position by a lever lock nut .
The apparatus being in the position shown by Fig. 2, the orifice i formed in the
lower part of the cylinder b opens directly into the interior of the container g, so that
the piston in its upward motion to the position shown at Fig. 3 sucks into the interior
of the cylinder 6 the fluid contained in the container g.
As soon as the piston commences to descend it carries with it, consequent on the
friction of its packing, the cylinder b and applies it to its fixed seat c, see Fig. 4, so
as to prevent all communication between the interior of the cylinder b and the
interior of the container g and to cause the orifice i to open into the delivery
d formed in the seat c.
passage
The piston continuing its descent drives into the passage d all the fluid which had
been sucked into the cylinder b, the fluid thus driven, in order to escape pushes back
the valve e which again closes automatically by the action of its spring, when the
delivery action is finished.

page_text: In consequence of the possibility of regulating the position of the sleeve f, the
useful suction stroke of the piston can be varied at will and a variable delivery
obtained ranging from zero to a maximum delivery corresponding with the complete
stroke of the piston, minus a certain fraction determined by the necessary rise of the
cylinder 6 to permit suction through the orifice i.
The variation of the delivery of my arrangement of pump can be regulated
automatically; the part serving as stop to the cylinder b is in that case movable and
is operated in any suitable manner, either by the governor of the engine, when it is
applied to oil or spirit engines, or by the lever of a float when it is applied to a boiler
feed apparatus; in order to obviate the reaction of the push of the cylinder, an
eccentric will be preferably employed as intermediary for the transmission of the
motion, and as the motion of the stop piece should be effected before it is in contact
with the cylinder, the power which this motion will necessitate will in all cases be
very small and easy to operate even at a distance.
If a certain number of pumps thus constructed are grouped together, several
points can be simultaneously fed at the same time, the apparatus for regulating the
stops could then be mounted on the same part which, by an easy motion, will permit
of stopping or of again putting in action the entire series of pumps without dis-
arranging their delivery, and further of increasing simultaneously the delivery of all
the pumps at the same time preserving the power of returning to the normal point
of delivery.
The upward motion of the piston can also be obtained, as shown at Fig. 5 by a
cam acting on a lever jointed to the piston rod a, and the delivery be effected either
by a spring or as represented in the drawing, by the action of a fluid under pressure
(steam, air &c.) constantly acting within an auxiliary cylinder upon a piston mounted
at the end of the piston rod a of the pump.
Figures 6 to 10 show the application of my arrangement of pump to a constant
delivery apparatus.
In this example, the cylinder b is guided by a disc f which also serves as a stop to
limit the motion of this cylinder b to the amount required to uncover its suction
orifice when the cylinder is moved by friction of the piston a.
pre-
The disc f has around its inner periphery notches j for the passage of the liquid.
The piston rod which is terminated by a knob k passes through a valve
ferably of spherical form held against the interior rim of the container g, by the
action of a spring pressing at one end against the piston a and at the other against
the inner face of the valve l.
In this apparatus, the upward motion of the piston is effected by hand, whilst the
downward or delivery action is effected by the force only of the spring m which is
compressed in the rise of the piston, but the general operation of the apparatus is the
same as in the previous example.
When the piston rod a commences to rise (the apparatus being in the position
shown at Fig. 6) the piston moves the cylinder 6 until this latter is stopped by the
disc fas shown at Fig. 7; the cylinder b then communicates by its orifice i with the
interior of the container g, on the further rise of the piston a this latter sucks in
through the orifice i, a determined quantity of the liquid contained in the container g,
see Fig. 8, then as soon as the knob k is released, the piston which is driven down-
wards by the action of the spring m commences by moving the cylinder b down on to
its fixed seat c, see Fig. 9, and drives the liquid, which was previously sucked in, into
the delivery passage, as previously described.
To fill the container g it is only necessary to push the valve down; in order that
this may be held down the sleeve of this valve is provided with a screw the point n
of which slides in a groove o formed in the piston rod and terminating in a circular
groove enabling the whole of the valve and its sleeve to be turned upon the piston
rod so that the screw point n when engaged in this latter groove, prevents the valve
from again closing by the action of the spring m. To reclose the valve, it is only
necessary to turn it slightly until the screw point n has arrived in front of the
groove o, so that this valve may again rise by the action of the spring m which keeps

page_text: it applied against the inner edge of the container g and thus secures hermetic
closure.
As in this apparatus the upward motion of the piston for suction is effected by
hand whilst the delivery is operated by the power of the spring only, it is clear that
the pressure of delivery will be always proportional to the power of the spring,
therefore if any suitable mechanical movement is adopted, by lever, can or other
suitable appliance, to effect the upward motion of the piston, that is to say, the
suction, an automatic apparatus of various pressure will be obtained by varying the
tension of the spring by any convenient means, besides the speed of descent of
the piston, that is to say, the delivery will depend on the consumption of liquid
effected in the delivery passage, for example by applying my arrangement to a
lubricating apparatus of multiple distribution, the quantity of oil delivered will be
in proportion to the number of points lubricated and to the delivery given to each of
them. Therefore supposing the maximum delivery of the pump to be equal to that
necessary for the maxima feed of all the points, the descent of the piston will only
be partially effected, for all deliveries below this maximum and therefore the suction
will no longer take place except in a certain proportion, dependent on the quantity
of oil used, which will be regulable for each point by means of a screw or needle
valve or other arrangement for varying the flow.
This individual regulation being effected for each point, this delivery can therefore
be modified and that simultaneously for all the points by the simple variation of the
tension of the spring by a screw or other regulation as above described.
The upward motion of the piston can be obtained, on the contrary, by the action of
a spring and the delivery motion be effected by hand, as is shown by the modification
represented at Fig. 11.
In this modification, in the state of rest, the movable cylinder b and the piston a
will by the action of the spring m abut against the stop ring f, the apparatus will
thus be always ready to deliver the liquid which has been sucked up by the upward
motion of the piston caused by the action of the spring.
It will be understood that my improved arrangements of pump may be varied in
form and dimensions and that the details may also be modified without departing
from my invention.
The modification shown at Figures 12 to 19 consists, in principle, in employing a
differential piston, the lower part of which, is of smaller diameter and has only for
effect to deliver the oil, whilst the upper part is of larger diameter, and is intended to
establish contact of the movable cylinder with the edge of the delivery orifice at the
same time assuring a perfect joint.
Moreover with this view channels are formed in the movable cylinder, so as to
allow the liquid to arrive as far as under the lower face of the larger piston, in such
manner that the liquid which is thus imprisoned at the moment of delivery,
assures a perfect joint not only between the movable cylinder and the delivery
passage, but also between this movable cylinder and the piston of small diameter.
This modification of my improved pump comprises a differential piston the lower
part a of which is of smaller diameter, and has for its object to drive the liquid into
the delivery opening d whilst the upper part a², is of larger diameter and is solely
intended to draw up a certain quantity of liquid and then to press on this liquid so as
to strongly press the movable cylinder on to its seat c and to assure a perfect joint,
as will be described hereafter.
The double piston a¹ a² receives as herein before described, its constant to and fro
movement from any suitable mechanical arrangement, and is located in a movable
cylinder which has two parts 61 62 of different diameters corresponding respectively
to those of the pistons a¹ a².
In the lower part 6 of the movable cylinder are made channels p opening at one
end into the space in the part 2 below the piston a² and at the other end' into a
circular space q, arranged so as to communicate with the interior of the receiver g
when the movable cylinder arrives at the top of its stroke.
The movable cylinder moves at its lower part in a guider having teeth or

page_text: projections s which allow the liquid contained in the receiver to enter the circular
space q when this cylinder is at the top of its stroke.
In this guider are formed in addition openings t, which, during the period of
admission enables the liquid, contained in the receiver g to enter the cylindrical
space c¹ in the seat c; this space c¹ is closed at its lower part by the escape valve e.
Thus as hereinbefore described, the useful stroke of the piston is regulated by
varying the position of the sleeve f which is secured in its regulated position by the
lock nut h.
The different parts of the present modification of pump being in the position shown
at Fig. 12, the apparatus works as follows:-
The double piston a¹ a² in moving upwards carries with it by friction during a part
of its stroke, the movable cylinder until this latter comes against the abutment sleeve f
(Fig. 15).
The movable cylinder is therefore no longer on its seat c and the circular space q
comes opposite the teeth or projections & in such manner that there is communication
between the interior of the receiver g and the channels p.
The double piston continuing to rise, the piston a² produces a suction of the liquid
through the channels p and into the interior of the free space which is at the lower
end of this piston.
When the double piston is at the top of its stroke (Fig. 17) the lower piston a¹ is
entirely out of the cylindrical space c¹ and the liquid of the receiver g enters freely
through the openings t into the space c¹. The piston then descends and takes with
it the movable cylinder which is applied to its seat c, Fig. 18, the circular space q is
then stopped by the sides of the guide'r.
In the continued downward motion of the piston, the piston a' delivers on the one
hand the liquid to be distributed contained in the space c¹ by forcing this latter to
push back the retaining valve e, on the other hand the liquid below the piston a² is
also driven.
This liquid cannot flow except through the play left between the movable cylinder
and its guide r, and the delivery will be made with a greater resistance in proportion
to the smallness of play left between this movable cylinder and its guide.
There results therefore from this resistance to the delivery a pressure on the upper
surface of the part b¹ of the movable cylinder which has the effect of applying this
latter firmly to its seat c, again the liquid thus compressed has the effect of opposing
any escape between the piston a¹ and the part 6 of the movable cylinder.
Under these conditions, it is ensured that the volume of liquid which has entered
the space c¹ during the period of admission will be completely delivered.
In order that the volume of liquid distributed at every stroke of the piston may be
ascertained, I have devised the following arrangement.
The upper piston a² passes through the regulating sleeve f and is provided with a
cylindrical space the interior diameter of which is equal to that of the lower
piston a¹, and in this space is located a rod which is fixed rigidly to the movable
cylinder by means of the cross pin w.
In order to permit of relative movement between the piston and its guide or
cylinder, a slot x is made in the piston.
The end of the rod v is flush with the end of the piston a² when the latter is at
the bottom of its stroke, Fig. 12.
During the first phase of the upward stroke of the piston, as the movable cylinder
is moved by the latter, the end of the rod remains always at the same level as the
end of the piston a² Fig. 15.
On the contrary, during the second phase of the upward stroke of the piston, as
the movable cylinder is stopped by the abutment sleeve f, the rod v remains
immovable and the piston a2 continues to rise; when this piston has arrived at the
top of its stroke, Fig. 17, the volume of the space y will correspond exactly with the
volume of liquid which is delivered by the piston a¹ in the course of its
descent.
When the abutment sleeve f is placed in a position enabling the movable cylinder

page_text: to accompany the piston through its entire stroke Fig. 19, it will be noted that the
volume of liquid delivered is nothing, and in this case the end of the rod v remains
always at the level of the end of the piston a².
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
1. An arrangement of pump having only one valve and consisting essentially of a
piston which moves in the interior of a movable cylinder, open at its lower part and
moved during a part of the stroke of the piston by the friction of the packing of
the latter and of a fixed seat on to which the end of this cylinder is applied during the
period of delivery, this seat being formed with a delivery passage provided with a
stop valve; the stroke of the cylinder being limited by an abutment either fixed or
adjustable at will substantially as herein set forth.
2. In an arrangement of pump having only one valve, the employment of a
differential piston, the lower part of which is of sinaller diameter and has the function
of driving into the delivery passage, the liquid which has entered during the
admission into the space in the fixed seat, upon which the movable cylinder is
applied, and the upper part of which is of larger diameter, and is intended only to
suck up a certain quantity of liquid, and then to press upon this liquid so as to
forcibly apply this movable cylinder to its seat and thus ensure a perfect tightness,
the flow of this liquid being only possible between the said cylinder and its lower
guide, substantially as herein set forth.
3. In an arrangement of pump having only one valve, as above claimed, the com-
bination therewith of an arrangement of delivery indicator, formed by the prolonga-
tion of the upper piston having a cylindrical space the interior diameter of which is
equal to that of the lower piston and in which is located a rod fixed rigidly to the
movable cylinder, the end of this rod being flush with the end of the upper piston
when the latter is at the bottom of its stroke, so that when this piston is
at the top of its stroke, the difference of stroke between the piston and
its enclosed rod produces in the interior of this piston a space the volume
of which corresponds to that of the liquid which is driven out by the lower piston
during its descent, substantially as herein set forth.
Dated th: 20th day of Ion 1000
HARRIS & MILLS,
23, Southampton Buildings, London, W.C., Agents.