Improvements in and connected with Fluid Motor Apparatus.
Year: 1890

page_text: Date of Application, 15th Nov., 1890
Complete Specihcation Left, 15th Sept., 1891-Accepted, 17th Oct., 1891
PROVISIONAL SPECIFICATION.
Improvements in and connected with Fluid Motor Apparatus.
I, MICHAEL MARY BROPHY, of the firm of James Slater and Company, of
21, High Holborn, in the County of London, Engineers, do hereby declare the
nature of this invention to be as follows:-
My invention chiefly relates to means whereby the power of a fluid motor may
be applied with a constantly varying leverage in direct proportion to the force
expended on the one part and the required amount of work on the other part,
thereby obtaining a maximum of efficiency for the force expended.
In carrying out my invention I employ two levers having suitably curved
surfaces and arranged to work in conjunction with one another in such a manner
that the surface of one lever at the greatest distance from its fulcrum is in connec-
tion with the portion of the surface of the other lever at the shortest distance from
its fulcrum, and that as the two levers move simultaneously the relative distances
from the fulcrums will decrease and increase respectively, as in elliptical wheels, in
graduated proportion.
In practice the curved surfaces may be provided with gear teeth, or one lever
may be connected with the other by means of a chain secured to the two levers at
or near the extremities most remote from their fulcrums. The rods of the driving
and driven pistons are respectively connected with the levers near their fulcrums by
means of pulleys and chains, rack-teeth and pinions or other suitable means in such
a manner that during the outward movement of one piston the other is moved
inwards and vice versa.
The arrangement hereinbefore described is of especial use for compressing air
for driving a motor, which air may be used more or less expansively, according
to the amount of work to be performed, this not being possible when hydraulic
power is directly employed, in which case a uniform quantity of water is used,
notwithstanding the variations in the amount of power required.
The pistons are preferably arranged to work vertically, and in order that all the
air compressed in the cylinder shall be forced into the receiver I use a layer of
water upon the top of the air-compressing piston, which water, when the said piston
is at the top of its stroke, entirely fills all the free space between the piston and the
discharge-valve, a small quantity of water is also employed within the reservoir
(which is above the air-compressing cylinder) to compensate for any leakage which
may take place around the piston.
The curvature of the surfaces of the two levers may be more or less varied
according to the variations of pressure in the two cylinders; and the relative areas
of the driving and driven pistons may be varied according to the pressure of the
motive fluid and the pressure of air to be obtained.
It is to be understood that my invention may be used for applying a diminishing
pressure, as in a steam engine, with a uniform force.
Dated the 15th day of November 1890.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.

page_text: Improvements in and connected with Fluid Motor Apparatus.
I, MICHAEL MARY BROPHY, of the firm of James Slater and Company, of
251, High Holborn, in the County of London, Engineers, 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 :-
My invention chiefly relates to means whereby the power of a fluid motor may
be applied with a constantly varying leverage in direct proportion to the force
expended on the one part and the required amount of work on the other part,
thereby obtaining a maximum of efficiency for the force expended.
In carrying out my invention I employ two levers having suitably curved surfaces
and arranged to work in conjunction with one another in such a manner that the
surface of one lever at the greatest distance from its fulcrum is in connection with
the portion of the surface of the other lever at the shortest distance from its fulcrum,
and that as the two levers move simultaneously the relative distances from the
fulcrums will decrease and increase respectively, as in elliptical wheels, in graduated
proportion.
In practice the curved surfaces may be provided with gear-teeth, or one lever
may be connected with the other by means of a chain secured to the two levers at
or near the extremities most remote from their fulcrums. The rods of the driving
and driven pistons are respectively connected with the levers near their fulcrums
by means of pulleys and chains, rack-teeth and pinions or other suitable means in
such a manner that, during the outward movement of one piston, the other is moved
inwards and vice versa.
The arrangement hereinbefore described is of especial use for compressing air
for driving a motor, which air inay be used more or less expansively, according to
the amount of work to be performed, this not being possible when hydraulic power
is directly employed, in which case a uniform quantity of water is used, notwith-
standing the variations in the amount of power required.
The pistons are preferably arranged to work vertically, and in order that all the
air compressed in the cylinder shall be forced into the receiver, I use a layer of
water upon the top of the air-compressing piston, which water, when the said piston
is at the top of its stroke, entirely fills all the free space between the piston and the
discharge-valve, a small quantity of water is also employed within the reservoir
(which is above the air-compressing cylinder) to compensate for any leakage which
may take place around the piston.
The relative areas of the driving and driven pistons may be varied according to
the pressure of the motive fluid and the pressure of air to be obtained.
It is to be understood that my invention may be used for applying a diminishing
pressure, as in a steam engine, with a uniform force.
To enable my invention to be fully understood I will describe it with reference to
apparatus in which hydraulic pressure is employed for compressing air which may
subsequently be used for any required purposes.
In the accompanying drawings,
Figure 1 is a front elevation of such apparatus; and,
Figure 2 is a side elevation of the same:
Figure 3 is a section on the line a a, Figure 1:
Figure 4 is a plan; and,
Figure 5 is a section on the line y y, Figure 2:
Figure 6 is a diagram hereinafter described.
a indicates the framing of the apparatus,
piston or ram therein. d is the air compressing
and having the valves ƒ, ƒ and the rod y, and
the hydraulic cylinder, and c the
cylinder, e the piston sliding therein
is the reservoir into which, the air

page_text: ()
5
ressed, being the valve for controlling communication between the said
reservoir and the cylinder d.
are the two levers through which the power is communicated from the
piston e to the piston e. k, kare the chains by means of which the pistons c and e
are respectively connected to the levers j, and j', the said chains, which are used
in duplicate and connected to a cross-head on opposite sides of the rods
prevent straining of the same as shewn most clearly in Figure 5, being secured to
and € to
the pulleys, respectively. m is the chain which serves to connect the two levers
so that they shall move simultaneously.
With this construction it will be understood that when under the pressure of
water the hydraulic piston c is moved downwards, the lever j will commence to
move in the direction of the arrow 1, Figure 3, and thereby move the lever in
the direction of the arrow 2 so that the chains will be wound upon the pulleys/
and thereby lift the piston e to compress the air in the cylinder d into the reservoir.
It will be understood that as these two levers move as hereinbefore stated in a
manner similarly to elliptical gear-wheels, that whilst the axial movement of the
lever is uniform, that of the lever j is rapid at first and then gradually decreases,
whereby during the first part of the upward movement of the piston e whilst the
work to be done is small the said piston moves rapidly whilst as the resistance to
the movement of the piston increases the speed diminishes.
It will be seen by reference to the drawings that the diameters of the chain
pulleys, are so proportioned relatively to the stroke of the pistons c and e that
the levers j, j only make half a revolution on their axes.
In the arrangement shewn in Figures 1 to 5 the weight of the piston e and of its
connections is depended upon for returning the parts ready for another impulse
under the force of the water.
additional weight may be attached to the lower end of the rod g. g, c' are stops
Should, however, this weight not be sufficient,
for stopping the rods g, c at the ends of their strokes.
n is the valve for controlling the admission and exit of the water into and from
the cylinder b. This valve may be operated by any suitable mechanism.
shewn in the drawings it is effected through the medium of the levers n', n², the
As
rod 3, the lever n' and the rod n³.
bearing and also through another oscillating bearing n' carried by a crank o
This rod n works through an oscillating
secured to the axis of the lever j. Between the two ends of the bearing n' and
stops o' on the said rod n³ are spiral springs p, p. 7, q' are brackets against the
faces of which the stops o¹, o2 are adapted to bear as hereinafter described.
lever only makes a movement of half a revolution in the direction of the arrow,
As the
Figure 2, and then returns during the outward movement of the piston c it follows
that the crank o makes a similar movement.
stop o comes into contact with the back face of the bracket q', as indicated by the
As the crank moves upwards, the
lotted lines, Figure 2, and as the bearing n' slides upon the said rod n it
compresses the spring p. Just as the crank o completes its half revolution, the
top of moves out of contact with the bracket q', whereby the said rod is moved
nder the reaction of the spring p¹ to the position indicated by the dotted lines r
o operate the valve to exhaust the water from the cylinder b. The knuckle
oint of the rod n' serves to limit the movement of the said rod under the action
f the spring pl by coming into contact with one end of the bearing n which is
ced with india-rubber or other material to form a cushion. During the movement
f the bar n' under the action of the spring p', the stop o is brought to the position
dicated by the dotted lines, Figure 2, so that, as the crank n' commences to
ove in the reverse direction to that in which it previously moved, the said stop o¹
ill bear against the front face of the bracket
mpressed. When, however, the crank just completes its half rotation in this
whereby the spring p will be
ckward direction the spring p reacts to move the rod n in the reverse direction,
stop n limiting the movement of the said rod in this direction by impinging
ainst the other cushioned face of the bearing nº.
It will be noticed by reference to Figures 1 and that the brackets q, q¹ are

page_text: slotted as shewn at s, s' respectively to allow of the oscillating movement of the
rod n³.
It is to be understood that I make no claim in the present application to the
valve operating mechanism hereinbefore described as it forms the subject matter of
an application dated September 15th 1891 No. 15667.
If it is desired to make the piston e double-acting, that is to say, to compress air
both on its in and out strokes, I make the hydraulic piston c also double acting,
and I arrange in connection therewith duplicate sets of pulleys and levers. This
arrangement will be understood by reference to Figure 6, where j, j indicate the
levers which cause the upward movement of the piston e during the downward
movement of the hydraulic piston c, and j, j the levers which cause the downward
movement of the piston e during the upward movement of the piston c.
In this arrangement of apparatus it is to be understood that the rod of the
piston e must be connected to the pulley by two sets of chains k, k wound around
the same in opposite directions in order that the said pulley shall be positively
rotated in both directions. Duplicate sets of chains ', ' must be similarly applied
to the rod of the piston e.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what 1
claim is :-
:―
1. The method of utilizing fluid pressure through the medium of levers in such
a manner that a uniform or decreasing force may be applied with an increasing or
uniform force, substantially as hereinbefore described.
2. The combination with a piston operated by fluid pressure of an arrangement
of levers and chains, substantially as described for operating a second piston for
pumping or compressing.
3. The improvements in apparatus, as hereinbefore described and illustrated in
the accompanying drawings for utilizing hydraulic pressure for compressing air.
Dated the 15th day of September 1891.
G. F. REDFERN & Co.,
4. South Street, Finsbury, London, Agents for the Applicant.