IMPROVEMENTS IN SPIRAL PUMPS AND IN APPARATUS EMPLOYED IN CONNECTION THEREWITH
Year: 1870

page_text: LETTERS PATENT to Thomas Schoenberger Blair, of Pittsburg,
Pennsylvania, in the United States of America, but at present
residing at Swansea, in the County of Glamorgan, for the Invention
of "IMPROVEMENTS IN SPIRAL PUMPS AND IN APPARATUS EMPLOYED IN
CONNECTION THEREWITH."
Sealed the 15th April 1871, and dated the 22nd October 1870.
PROVISIONAL SPECIFICATION left by the said Thomas Schoenberger
Blair at the Office of the Commissioners of Patents, with his Petition,
on the 22nd October 1870.
I, THOMAS SCHOENBERGER BLAIR, of Pittsburg, Pennsylvania, in the
United States of America, but at present residing at Swansea, in the
County of Glamorgan, do hereby declare the nature of the said Invention

page_text: for "IMPROVEMENTS IN SPIRAL PUMPS AND IN APPARATUS EMPLOYED IN CONNECTION
THEREWITH," to be as follows:-
It has been practically proved by Morin and others that the spiral
pump when properly constructed will within certain limits of size yield a
high coefficient of useful effect, while at the same time the simplicity of
its construction affords a considerable economy both in first cost and
maintenance, as compared with the cost and maintenance of pumps of
other construction. It has however not been practically possible here-
tofore to employ the spiral pump on a large scale, because it was found
that when the vertical pipe or rising main up which the fluid was forced
exceeded a certain sectional area, the air that entered with the fluid
from the pump in a state of 'compression would escape up through
the column of fluid in such manner as to cause a loss of the motive
power represented by its expansion from the compressed state to the
ordinary atmospheric pressure.
Now my present Invention has for its object to overcome this difficulty
and enable such spiral pumps to be constructed on a large scale by so
forming the rising main of the pump and regulating the entrance of fluid
and air into the same that although it may be of considerable sectional area,
yet the air shall in passing up it be caused usefully to expend the motive
power due to its compression in assisting to raise the fluid passing up
with it. This end I attain by various means. Thus according to one
method I subdivide the sectional area of the conduit into a number of
smaller conduits, each of about the maximum sectional area that may
be employed without causing the air to escape as before stated. Or I
employ in place of one rising main of large sectional area a number of
rising mains of small sectional area all communicating at the lower end
with the orifice of the spiral pump.
According to another method I cause the air and fluid to pass from
the spiral pump into a closed chamber or air vessel, through the upper
part of which the lower end of the rising main enters and is made to
pass down nearly to the bottom of the air vessel.. The lower end of the
rising main is open, and the surface of that portion contained within the
air vessel is provided with perforations or apertures, so that as the fluid
and air pass into the air vessel from the pump the fluid passes from the
bottom of the former up through the open end of the rising main, while
the air under pressure in rising into the upper part of the air vessel is

page_text: caused by the existing pressure to enter through the lateral perforations
into the rising main, and in thus. being made to mix intimately in the
form of small bubbles with the ascending column of fluid it is effectually
retained in the latter, so as to produce the required effect by its expansion.
Or in place of causing the air under pressure to pass from the air vessel
into the rising main, it may be partially or wholly conducted away
through a pipe to any suitable known construction of motive-power engine
capable of being worked by compressed air, which engine may be made
to drive another spiral pump of smaller dimensions, or it may be otherwise
employed for doing any required work, such as for driving, an ordinary
suction pump or centrifugal pump for raising the fluid from a lower
level to the reservoir in which the spiral pump is situated.. Or the
'compressed air may conveniently and economically be made to act
directly upon an apparatus of the following arrangement:-For so raising
the water a closed air-tight chamber is immersed in the water or other
fluid at the lower level, which chamber has an aperture at the upper end
provided with a valve through which the compressed air enters from.a
pipe leading to the air vessel of the spiral pump. It also has another
aperture at the top also provided with a valve through which the air
after doing duty is allowed to escape. At the lower end the chamber
has one or more valves opening inwards, through which the water in
which the chamber is immersed can enter the latter, and it is also there
provided with a pipe having a stop back valve communicating with the
upper reservoir containing the spiral pump.
In the chamber is contained a float which in rising and falling with
the level of the water therein operates the before-mentioned upper valves
by means of a rod and any suitable known reversing mechanism in the
following manner: Assuming the chamber to be filled with water
passing in through the lower valves from the basin in which it is
immersed, the float has. risen to the top of the chamber in. arriving, in
which position it effects the closing of the escape air valve and: opens
the inlet valve for compressed air. This compressed air in entering the
chamber forces the water out of the same and up the pipe at the lower
end into the reservoir of the spiral pump. As the water. level sinks in
the chamber the float descends, and at any desired point of its descent
it effects the closing of the air inlet valve so as to cause the compressed
air in the chamber to force the remainder of the water out. by its
'

page_text: expansion. Arrived at the bottom of the chamber the float effects the
opening of the escape air valve, and the water of the lower basin will
then enter and fill the chamber as before. Two such apparatus may
conveniently be connected with the spiral pump, and made to work
alternately, so as to maintain a continuous discharge of air and water.
A safety valve or air outlet placed in the chamber into which the con-
tents of the spiral pump are discharged will prevent the air from getting
into the pipe which discharges the water, so that each system will work
independently of the other.
According to another method I so construct the rising main of large
sectional area that the direct line of ascent of the fluid and air is
disturbed; so as to prevent the formation of a central core of ascending
air, which if undisturbed would escape in a condition of greater or less
compression representing a corresponding loss of power. This may be
effected either by forming the rising main with bends or deflections at
various points or with enlargements and contractions, or by introducing
into the same lateral projections or central obstructions or perforated
diaphragms or wire gauze, which would deflect and break up any
escaping body of air.
Or according to another method I introduce into the conduit any
known contrivance, such as a dash wheel or series of revolving blades,
that will effect an intimate admixture of the air with the fluid at one or
more points in the height of the conduit.
Or according to another method I arrest any escaping volume of air,
and after separating it from the fluid in its ascent I reintroduce it into
the fluid under more favourable conditions. This may, for instance, be
effected by constructing one or more closed chambers into which the
conduit opens at one or more points of its height and from which the
fluid passes through a lateral opening into a continuation of the conduit
while the air is conducted through a pipe leading from the top of the
chamber into the side of the conduit. In constructing such spiral
pumps of large capacity I prefer to effect a water-tight joint between
the orifice of the pump and the rising main by means of the well known
"Bramah collar" such as is used in hydraulic presses. Also in order to
reduce the power required for rotating the pump to a minimum, I
support the bearings of the same on antifriction wheels, and the drum
of the pump may also for this purpose. be formed hollow, so as to float
:

page_text: the pump more or less in the water in which it is partially immersed as
has been already proposed by Mr. Airy. The water may readily be main-
tained at a constant or nearly constant level in the reservoir in which
the pump is placed by the application of valves or sluices opened or
closed by floats arranged in any known manner.
Such spiral pumps
when constructed on a large scale may be conveniently and economically
worked by a comparatively small steam or other motive power engine
working at a quick speed and imparting the requisite slow rotary motion.
to the pump at which it works with the maximum useful effect by
means of speed reducing gearing.