IMPROVEMENTS IN APPARATUS FOR EXHAUSTING, LIFTING, FORCING OR MEASURING FLUIDS
Year: 1882

page_text: LETTERS PATENT to Houston Stewart Stewart of Palace Chambers, St Stephens,
in the city of Westminster for an Invention of "IMPROVEMENTS IN APPARATUS
FOR EXHAUSTING, LIFTING, FORCING OR MEASURING FLUIDS
"
PROVISIONAL, SPECIFICATION left by the said Houston Stewart Stewart
at the Office of the Commissioners of Patents on the 25th November 1882.
HOUSTON STEWART STEWART of Palace Chambers, St Stephens, in the City of
Westminster, "IMPROVEMENTS IN APPARATUS FOR EXHAUSTING, LIFTING, FORCING,
OR MEASURING FLUIDS."
This invention has for its object the improvement of apparatus for exhausting,
lifting, forcing or measuring fluids for which Lotters Patent N° 2588 dated
June 25, 1880 were granted to me, and especially with regard to such apparatus
as requires to be driven at a considerable speed.
The invention consists of a cylindrical metal case or chamber through which
a central shaft passes, the shaft having attached to it vanes as described in the
specification of the above mentioned patent.-In the present invention however
the cogged gearing by which the shaft and vanes are made to revolve is dispensed
with, and in place of it the following arrangement of apparatus is adopted. To
that part of the barrel of one of the vanes which projects through the end of
the case a crank arm is fixed, and a similar crank arm is attached to the spindle.
Each of the crank arms has near its extremity a stud or crank pin sufficiently long
to enter a corresponding metal block which is capable of sliding to and fro in a
slotted bar. This bar is at right angles to the main driving shaft on which is
keyed the belt pulley that serves to transmit motion from the source of power to
the vanes.
The main shaft just alluded to is placed parallel but eccentrically to
the axis of the cylindrical chamber, consequently when motion is imparted to it
the slotted bar will revolve carrying with it the arms attached to the vane and
spindle. The vanes will therefore revolve, but owing to the main shaft being
placed eccentrically to the spindle and vanes, the vanes will move at different

page_text: speeds at different points of their travel. Both vanes are continually revolving
and no dead point exists, or shock can ensue, but the rate at which they travel
varies with the position they occupy, the one vane moving only the distance from
the outlet to the inlet, while the other moves a much greater distance from the
inlet to the outlet. By this means a much more regular flow or delivery of the
fluid is ensured
The position of the outlet and inlet ports respectively will vary according to the
eccentricity of the driving shaft to the axis of the cylindrical chamber.
Wheels or rollers may be used instead of the metal blocks, or rollers may be used
in combination with them.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Houston Stewart Stewart in the Great Seal Patent Office on the
25th May 1883.
HOUSTON STEWART STEWART of Palace Chambers, St Stephens, in the City of
Westminster "IMPROVEMENTS IN APPARATUS FOR EXHAUSTING, LIFTING FORCING
OR MEASURING FLUIDS
"
My invention of improvements in apparatus for exhausting, lifting, forcing, or
measuring fluids, consists in an improved arrangement of rotary apparatus whereby
greater efficiency and simplicity of action are obtained, than has hitherto usually
been the case. The invention has for its object the improvements of pumps or
apparatus similar to those described in the Specification of Letters Patent granted
to me, dated 25th June 1880, N° 2588, but instead of the motion of the vanes being
stopped or brought to rest, their velocity is so varied that each of them alternately
travels from the inlet to the outlet port, in the same space of time as is occupied by
the other vane in travelling from the outlet to the inlet port, by which means great
advantages of working are obtained particularly in cases where the machine has to
be driven at high speeds. In order that my improvements may be understood,
I proceed to describe the same by means of the accompanying drawings.
Figs. 1, 2 and 3 are respectively plan, part elevation, and section of the machine,
at the moment when the vanes are in the position of closest proximity to one
another and when their velocity is alike. Figs. 4, 5 and 6 are similar views, at the
moment when the vanes are at their greatest distance apart, and when the
difference in their velocity is greatest. Figs. 7, 8, 9 and 10 are details of the vanes,
and the crank arms by which they are actuated. In these Figs. the same letters of
reference indicate corresponding parts throughout.
A is the cylinder,-B, B₁ are the inlet and outlet ports. These are preferably
formed by a series of small holes extending nearly from end to end of the cylinder,
In this way the fluid which is being discharged by the approaching vane, is delivered
more uniformly than when concentrated at a single aperture; further the metal
between these small holes serves as a support to the shoes G G₁ while passing the
ports. And further in this way an aggregate area consistent with the large
capacity of the supply and delivery pipes can be obtained in a very small proportion
of the circumference of the cylinder, C, C¹, are the inlet and outlet pipes-
D D¹ are the cylinder ends or covers.E, E are the blades of the vanes.
F F are
the barrels of the vanes.—G, G³ are adjustable shoes of iron, gun-metal, or other
suitable metal or alloy.-H, H¹ are spaces for the insertion of springs of india-
rubber or other suitable means of obtaining adjustment if required.-I, I' are
packings of any suitable metal or alloy.-J is a spindle passing through the axis of
the cylinder. This spindle may be either solid or hollow and in the latter case
may be used as a channel of lubrication.-K, K' are stuffing boxes.-L, L' are crank
arms.-M, M¹ are crank pins.-N, N' are slide blocks.-0 is a crosshead attached
to the shaft from which the motion is to be imparted, and in [or on] which the
slide blocks N, N¹ are free to slide. The spindle J passes through the barrel of
each of the vanes. The barrel is securely fixed to the spindle, while the barrel F'
is free to revolve upon it. The barrel F is extended and passes through the
stuffing box K-The crank arms L L' being securely fixed respectively to the
spindle J, and to the barrel F' it will be seen that motion may be imparted to one
of the blades by means of the crank arm L and to the other by means of the crank
arm L. The axis of the shaft from which motion is to be imparted is eccentric to
the axis of the cylinder, and the crank arms L, L' are propelled at constantly

page_text: changing velocities, according as the slide blocks N, N¹ are brought nearer to, or
further from, the axis of the shaft and crosshead.
The differential movements thus produced may be varied according to the
eccentricity of the cross, the position of the ports being correspondingly varied.
Thus the eccentricity of the belt pulley spindle as shown on the drawings is
four fifths of the radius of the crank arms. If this proportion be increased the
vanes will be brought nearer together at the moment when their velocity is equal,
and the machine will thus deliver a larger volume per revolution, but with a
resulting decrease of pressure. And conversely if a high pressure is required,
the proportion of eccentricity to crank radius may be reduced and the necessary
differential power obtained. The shoes G, Q¹ as well as the packings I, I' may
with advantage be dispensed with where the conditions of pressure permit. In
this case the radius of the blades E, E' is increased so as to produce contact or
a pear approach to contact with the shell of the cylinder.
Instead of the slide blocks N, N', rollers may be employed or a combination of
blocks and rollers.
Having thus described the nature of my invention, I do not confine myself to the
exact form or proportions I show on the drawings, but I hereby declare that what
I claim as of my invention, is the improved rotary apparatus constructed
substantially as and for the purposes herein before described.
In witness whereof I the said Houston Stewart Stewart have hereunto set
my hand and seal this Twenty fifth day of May in the year of our Lord
One thousand eight hundred and eighty-three.
CARITY D