Improvements in and relating to Centrifugal Pumps.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in and relating to Centrifugal Pumps.
I, JOSEPH BERNAYS, of No. 96, Newgate Street, in the City of London, Civil
Engineer, do hereby declare the nature of this invention to be as follows:-
My invention relates to that class of pumps known as centrifugal pumps, and
consists of improvements whereby the pump situated above the level of the liquid
to be raised and suction pipe may be efficiently and automatically primed or filled
with liquid on starting to enable it to draw water or liquid at once dispensing with
the use of a foot valve at the bottom of the suction pipe or of an aspirator with
retaining valve at top as generally used and by which improvements also the
volume of flow through the pump particularly at small heads is facilitated and
increased. Where the pump is high above the liquid level to be raised, I prefer to
use for the purpose a device described hereinafter as an air lock and with those
situated a few feet only above the said level I preferably employ for the same
purpose, an auxiliary pan or propeller though either may be adopted in each case
and with centrifugal pumps of either the horizontal or vertical descriptions though
the former device is more easily and practically applicable to pumps with horizon-
tal spindles and the latter to those with vertical spindles.
I will first describe the nature of my invention as most practically applied to
pumps with horizontal spindles.
I adapt to the pump casing, either by casing therewith or connecting
thereto by pipes, a closed chamber or receptacle placed about level with the top of
the said pump, capable of holding a sufficient quantity of water. To that receptacle
are attached two pipe connections, one leading from its lowest part direct to the
pump inlet, the other from the top of the receptacle down into the water which is
to be raised.
Thus, the receptacle is interposed between the suction pipes and the
pump forming an automatic air lock between them, the suction pipes delivering
the raised water into the receptacle at its upper end, the pump drawing it out at
the lower end.
The cubical contents of the air lock are proportioned to the extent of the vacuum
required for drawing the liquid up to the pump and will in practice vary from
two to four or five times the contents of the empty part of the suction pipes at start-
ing. Upon the removal of the water from the receptacle through the action of the
fan the vacuum thereby caused in the chamber or air lock which is in communica-
tion with the suction pipe or through which the suction stream passes will suffice to
sufficiently rarefy the air in the suction pipe to cause a flow of water through that
pipe into the said chamber or air lock.
The pump, from that moment, is continuously and efficiently supplied
with water from the suction pipe or well.
The chamber or airlock is also at its highest point provided with an air tap or
connected by a small pipe with the pump delivery pipe for allowing the escape of

page_text: J
the air when the pump and air lock are being filled. The said air pipe may also
have a cock or tap by which the said pipe may be closed when its purpose as above
described has been fulfilled.
This arrangement obviates entirely the necessity for the use of a foot valve upon
the suction pipe in starting the pump or the alternative use of an aspirator with
retaining valve at any time & thus, offers the great advantage of a clear way
through the suction pipe and pump without valves.
If however it is desired to use a foot valve, but to keep it accessible at all times
above the level of the water to be raised, such foot valve will be situated at some little
height above the extremity of the suction pipe and would leave a short length of
pipe below the foot, valve in-which a volume of air at starting may exist which
would give trouble or delay in starting the pump. To obviate this I may adapt
a simplified modification of my air lock to the suction pipe itself, consisting of a
receptacle of very moderate size (as it only has to deal with a small volume of air)
with a dip pipe therein so arranged as to allow the water to rise to the pump
when the fan commences to work whilst the air is retained in the lock or chamber.
From the highest point of this air lock also as before described a small air pipe
controlled by a cock leads to the delivery neck of the pump."
I similarly carry out my "invention for automatically priming a centrifugal
pump most practically for one with a vertical spindle in the, following way.
It has hitherto been the custom in all installations to fix the fan at the lower end
of the spindle entirely immersed in the liquid which is to be raised.
I
My improvement consists in raising the pump fan to a position at some little
height above the level of the water to be raised and in attaching to the pump casing
below the fan a tail pipe or chamber and reaching well down into the water.
shape the lower end of the tail pipe suitably to form the delivery channel for a
small secondary centrifugal fan which is attached to the lengthened end of the
pump spindle below the water level.
"
(I 4
Upon the spindle being made to rotate at suitable speed, both fans revolving
together, the lower fan being immersed will raise the water through the tail pipe
or receptacle into the main pump chamber and the main fan will assume work as
soon as it is covered by the water.
This system is also applicable to pumps with horizontal spindles in which case I
place the auxiliary fan at the bottom end of the suction pipe immersed in the water
to be raised and fit it to a vertical spindle which is geared at its upper end to the
pump spindle or may be driven from any independent source.
In both cases the auxiliary fan may be fitted to its spindle so as to lift out of the
water way so soon as the stream of water operated by the main pump when in full
action shall produce a lifting effect upon the said auxiliary fan. Or instead of a
secondary centrifugal fan I fit to the lower end of the pump spindle one or more
screw propellors of a suitable pitch for raising the water to the height of the main
pump chamber at starting.
In
The above improvements are applicable to all kinds of centrifugal pumps and
also particularly to such. as. are made according to the Specification attached to
the Letters Patent granted to me under No. 1758 and dated 14th July 1864.
the latter description of pumps. I take further advantage of the improved suction
arrangements hereinbefore described, more particularly under small heads of
delivery by retaining only the outer working joints. between the discs and the
delivery channel, but removing the similar joint between the inner openings of
the discs and the inlet passages of the suction pipes which hitherto had been
required with all centrifugal pumps. At the same time I perforate the sides of
the discs with holes generally one in each of the spaces between the propelling
arms, thereby effecting direct communication between the outsides of the discs
and the space between the arms. The suction of water or other liquid can now
enter the fan when at work through these holes in addition to that which enters by
the ordinary central openings, thereby'augmenting with a free suction supply the
quantity of water delivered."
..
- 1

page_text: Further, to allow issue of such augmented volume with minimum resistance
from the casing, I make the delivery passage around, the pump, rectangular in
shape-in cross-section with largely rounded corners and of a width throughout equal
to the diameter of the delivery pipe and I set out the external or circumferential
wall of this delivery passage in a spiral struck from two centres' at equal distances
above and below the centre of the disc casing relatively to the concentric periphery
of the pump fan apportioning the curve in such a manner as to leave the radial
depth of the channel at its narrowest part at least equal to the clear width between
the working discs at their outer diameter and, at the widest part such as to make
the sectional area of the channel at that point about equal to the area of the
delivery, pipe, pas
.,,་
COMPLETE SPECIFICATION.
...
Improvements in and relating to Centrifugal Pumps. :
14.
3.9
"
I, JOSEPHI BERNAYS, of 96, Newgate Street, in the City of London, Civil 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:
23.
5:
we de
1. I
"
My invention relates to that class of pumps known as "centrifugal pumps, and
consists of improvements whereby, the pump situated above the level of the liquid
to be raised and suction, pipe may be.efficiently and automatically primed or filled
with liquid on starting to enable it to draw water or liquid at once, dispensing with
the use of a foot-valve at the bottom of the suction pipe, or of an aspirator with
retaining valve at top. as generally used and by which improvements also the
volume of flow, through the pump, particularly, at small, heads, is facilitated and
increased. Where the pump is high above the liquid level to be raised I prefer to
use for the purpose a device described hereinafter as an air-lock'; and with those
situated a few feet only above the said level I preferably employ for the same
purpose an auxiliary fan or propeller, though either may be adapted in each case
and with centrifugal pumps of either the horizontal or vertical description, though
the former device is more easily and practically applicable to pumps with horizon-
tal spindles, and the latter to those with vertical spindles.
I will first describe the nature of my invention, as most practically applied to
pumps with horizontal spindles.
I adapt to the pump casing, either by casting therewith, or connecting
thereto, by pipes, a closed chamber or cistern, placed about level with top of
the said punip, capable of holding a sufficient quantity, of water. To that cistern
are attached two pipe connections, one leading from its lowest part direct to the
pump inlet, the other from the top of the cistern, down into the water which is
to be raised. Thus the cistern is interposed between the suction pipes and the
pump, forming an automatic air-lock between them, the suction pipes delivering
the raised water into the receptacle at its upper end the pump drawing it out at
the lower end. Upon the removal of the water from the cistern through the
action of the fan the vacuum thereby caused in the cistern. or air-lock, which is
in communication' with the suction pipe, or through which the suction-stream
passes; will suffice' to sufficiently rarefy the air in the suction pipe to cause a flow
of water through that pipe into the said cistern or air-lock.
.

page_text: The pump, from that moment, is continuously and efficiently supplied with
water from the suction pipe or well.
The cistern or air-lock is also, at its highest point, provided with an air-tap, or
connected by a small pipe with the pump delivery pipe, for allowing the escape of
the air when the pump and air-lock are being filled. The said air pipe may also
have a cock or tap by which the said pipe may be closed, when its purpose as
above described has been fulfilled.
This arrangement obviates entirely the necessity for the use of a foot valve upon
the suction pipe in starting the pump or the alternative use of an aspirator with
retaining valve at any time, and thus offers the great advantage of a clear way
through the suction pipe and pump without valves.
If however it is desired to use a foot valve, but to keep it accessible at all times
above the level of the water to be raised, such foot valve will be situated at some little
height above the extremity of the suction pipe, and would leave a short length of
pipe below the foot valve in which a volume of air at starting may exist, which
would give trouble or delay in starting the pump. To obviate this
may adapt
a simplified modification of my air lock to the suction pipe itself, consisting of a
receptacle of very moderate size (as it only has to deal with a small volume of air)
with a dip pipe therein so arranged as to allow the water to rise to the pump when
the fan commences to work whilst the air is retained in the lock or chamber. From
the highest point of this air lock also as before described, a small air-pipe, con-
trolled by a cock leads to the delivery neck of the pump.
I similarly carry out my invention for automatically priming a centrifugal
pump most practically for one with a vertical spindle in the following way.
It has hitherto been the custom in all such installations to fix the fan at the
lower end of the spindle entirely immersed in the liquid which is to be raised.
My improvement consists in raising the pump fan to a position at some little
height above the level of the water to be raised, and in attaching to the pump
casing below the fan a tail pipe or chamber and reaching well down into the
water.
I shape the lower end of the tail pipe suitably to form the delivery channel for
a small secondary centrifugal fan which is attached to the lengthened end of the
pump spindle below the water level.
Upon the spindle being made to rotate at suitable speed both fans revolving
together the lower fan being immersed will raise the water through the tail pipe
or receptacle into the main pump chamber, and the main fan will assume work as
soon as it is covered by the water.
This system is also applicable to pumps with horizontal spindles in which case I
place the auxiliary fan at the bottom end of the suction pipe immersed in the
water to be raised and fit it to a vertical spindle which is geared at its upper end
to the pump spindle or may be driven from any independent source.
In both cases the auxiliary fan may be fitted to its spindle so as to lift out of the
water way so soon as the stream of water operated by the main pump when in
full action shall produce a lifting effect upon the said auxiliary fan.
Or, instead of a secondary centrifugal fan I fit to the lower end of the pump
spindle one or more screw propellers of a suitable pitch for raising the water to
the height of the main pump chamber at starting.
The above improvements are applicable to all kinds of centrifugal pumps and
also particularly to such as are made according to the Specification attached to the
Letters Patent granted to me under No. 1758 and dated 14 July 1864.
Where my
aforesaid improvements are adapted to such pumps I find it advantageous, more
particularly under small heads of delivery, to retain only the outer working joints
between the discs and the delivery channel and to remove the similar joint between
the inner openings of the discs and the inlet passages of the suction pipes which
hitherto had been required with all centrifugal pumps. At the same time I per-
forate the sides of the discs with holes generally one in each of the spaces between
the propelling arms, thereby effecting direct communication between the outsides

page_text: shown in Figures-1-and 2'; and is attached by the flanged pipe E to the indraught
of a centrifugal pump."
24
-4
C, is the cistern or air-lock, in this case of cylindrical shape; the suction pipe D
entering from below but reaching within the said cistern to near its upper
extremity.
+.
The large flanged opening L, covered by a blank 'flange, is provided, to enable
horizontal supplementary pipes to be attached to the cistern or air-lock C, to
increase its capacity to any desired extent..
In Fig. 3 the cistern or air-lock C is adapted to the suction pipe D, in combina-
tion with a foot-valve M, but when my improved device is used, this foot-valve
may be placed above the level of the water, and therefore accessible.
The indraught to the pump E is in this case continued downwards within the
cistern, C, the lower open end being protected by a baffle K.
The action of the above described apparatus is as follows:-
When the cistern C and pump casing has been primed or filled with water,
which is facilitated by the opening of the air-snifting pipe F or of the cock G, the
starting and restarting of the pump withdraws the water easily and at 'once from
the cistern C, thereby causing a prompt upward flow of water through the suction
pipe D. Thus the pump will promptly start at any time, and this is effected without
the necessary use of a foot-valve, offering the great advantage of a clear way through
the suction pipe and pump, without a valve obstruction; or if a foot-valve K bé
desired to be used, it may be placed above the level of the water which is to be
raised, and therefore remains accessible at all times.
In Figures 4 and 5 usual and convenient forms of centrifugal pumps B are
shown with vertical spindles BI which are elongated, downwards into a lengthened
under casing or suction chamber D', formed suitably as a delivery channel to an
auxiliary centrifugal lifting fan or propeller 1', keyed to the elongated spindle B¹,
and placed in the lower neck of such chamber. The said lower fan P being always
immersed in the water, will raise the water through the tail pipe into the main
pump chamber and the main fan B will assume work as soon as it is covered by
the water. When the ascending current no longer depends upon P for its lifting,
the flow of water upwards will lift the auxiliary fan. P out of the neck of the
chamber D', if it is fitted so as to slip upwards upon the spindle B₁, by a feather in
the boss of P, engaging in a vertical or spiral slot Q in the spindle B, or by equi-
valent means. This will tend to remove all obstruction from the throat of the tail
pipe, when in regular work.
Upon the pump stopping, the auxiliary fan P will again fall by its weight
into the desired position in the throat of the tail pipe for most effective lift on
restarting.
In Figure 6 I show an arrangement of a centrifugal pump with horizontal
spindle B geared by mitre or bevil gearing R to a vertical spindle S carrying an
auxiliary lifting fan or propeller P in the throat of the suction pipe. D as before
described.
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
I claim is
;
* :
1st. In combination with the suction pipe of a centrifugal pump; a. cistern or
receptacle, situated between the said suction pipe and the said pump, having an
exit to the inlet of the pump from its lower part, and an entry for the ascending
column of, water from the tail pipe at its upper part, with or without means for
discharging, the air on filling, thus forming an air-lock, or water seal, in the
continuity of the said suction pipe.
:
...
2nd. A cistern or receptacle, situated between a centrifugal pump and its suction
pipe adapted by its entry and exit passages to form an air-lock or water seal to
the said suction pipe, having a capacity according to the depth of suction, substan-
tially as described.

page_text: 3rd. In the suction pipe of a centrifugal pump, a cistern or receptacle, formed in
and about the same, having an internal dip pipe, protected by a baffle, leading to
the inlet pipe to pump, and a direct lower entry from the suction pipe, in com-
bination with an accessible foot-valve, situated below the said cistern, but above
the level of the water to be lifted, substantially as described.
4th. In combination with the main fan of a centrifugal pump with vertical
spindle, and situated above the level of the water, a submerged auxiliary lifting
fan or propeller or propellers, rotating with the elongated spindle of the main fan
or driven therefrom, and situated in the throat of an extended casing, forming part
of the suction pipe of the main pump substantially as described.
5th. The combination of parts and arrangements of the suction pipe of a centri-
fugal fan substantially as and for the purposes described and as illustrated here-
with.
FELL & JAMES,
Agents for the Applicant, 1, Queen Victoria Street, London, E.C.