Improvements in Helico-centrifugal Pumps, Single or Connected.
Year: 1897

page_text: Date of Application, 7th Dec., 1897-Accepted, 12th Feb., 1898
COMPLETE SPECIFICATION.
Improvements in Helico-centrifugal Pumps, Single or Connected.
I, CLAUDE GUSTAVE PINETTE, of Chalons sur Saône (Saône & Loire), in the
Republic of France, Mechanician, 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 has for its object further improvements in single or connected
helico-centrifugal pumps of the kind for which a Patent No. 3666 of February 18th,
1896 has been granted.
In order to allow of these improvements being better understood reference will
be made to the accompanying drawings, in which:
-
Figure 1 is an elevation in longitudinal section along the axis of a single pump
fitted with my improvements;
Figures 2 and 3 are transverse sections on the lines X Y and X¹ Y¹ respectively
of Figure 1;
Figures 4 and 5 are detail views of modifications of construction relating to
Figure 1;
Figure 6 is an elevation in longitudinal section along its axis of connected pumps
arranged on the same principles;
Figure 7 is a transverse section on the line Z Z¹ of Figure 6;
Figure 8 is a longitudinal vertical section of a particular arrangement of abut-
ment box placed in prolongation of the suction body and employed where the spindle
of the pump is directly operated by an electric motor or other suitable motor.
The same letters of reference represent the same parts in the various figures.
The propeller P, Figure 1, is here provided with a casing C arranged adjusted
and fixed on the edge of the helix H. This casing therefore revolves with the pro-
peller. It is also as thin as possible and has in its smallest diameter a projection
or flange E provided with a deep groove b.
The water port from the propeller P into the body of the suction part A consists
of a ring B cast on the shell or casing G, or better still arranged and maintained
between the joint in this casing and the body of the suction part A. This ring has
two deep grooves a and d opposite the flange E of the casing of the propeller, said
grooves being arranged in such a way that the ring and the flange engage recipro-
cally with as slight a lateral play as possible and a longitudinal play allowing
sufficient margin for the shaft of the propeller to have if required, a reciprocating
movement of a few millimetres and this without the reciprocal engagement being
destroyed. For pumps without spiral suction bodies for instance drawing water
by an elbow or curved joint, the ring B is arranged as shown in Figure 5.
The flange or shoulder E may also be arranged on the casing C of the propeller
as shown in Figure 4 and have several deep grooves b b instead of a single one.
By increasing the number of deep grooves & d'An the ring B, multiple reciprocal
engagements may be obtained.
The revolving casing C also penetrates as much as possible, Figures 1 and 6, into
the interior of the forcing body R, and further I arrange between this casing and

page_text: the casing G a large space 0 enabling water contained in this space to assume by
influence a speed of rotation little inferior to that of the revolving casing C. The
improvements hereinbefore specified may be applied equally well to single or com-
nected pumps.
In connected pumps mounted on the same frame, I have simplified as follows the
arrangement of the central coupling M M¹ connecting the two pumps, mention of
which was made in my previous Patent. This coupling is formed simply by bolt-
ing together the flanges of the central boxes M M of the forcing bodies R R₁ of
each pump, Figure 6. The shaft is guided by a central sleeve D having longi-
tudinal ridges or ribs m leaving between them wide passages rr, Figures 6 and 7,
which allow water contained in the interior of the propeller P¹ to reach the chamber S
and to establish there the same pressure as in the interior of this propeller.
The advantages of my improved construction are as follows:-
1. Very slight longitudinal encumbrance, the length of the casing G being
reduced by the quantity by which the propeller and its casing penetrate the body of
the forcing apparatus R.
2. A reduction of reaction or longitudinal thrust on the shaft, the pressure in the
interior of the propeller having as counterpart the pressure on the exterior surfaces
of the revolving casing C.
3. The removal, or dispensing with the regulating, of the play of the spiral as
regards the casing of the propeller, the last adjustment being indispensable when
the propeller is not provided with a casing revolving with it. It is in fact evident
that the working of the pump cannot be affected in consequence of a more or less
considerable variation in the longitudinal play allowed between the flange E and
the ring B.
4. A considerable diminution of the passive resistance due to friction of the
external surface of the revolving casing C upon the surrounding water because this
casing revolves on the one hand in the water contained in the space O and on the
other hand in the water in circulation in the forcing body, that is to say in water
having itself a considerable speed of rotation in the same direction.
5. An important diminution in the loss of discharge resulting from the return
towards the suction of water contained in the space, because such water having no
other issue than narrow passages and interrupted passages profiled on the line dba,
Figure 1, will experience such loss of power that it can only circulate at a very slow
speed. This result is therefore constant whatever may be the longitudinal play
between the flange E and the projection B provided the parts E and B do not cease
to engage reciprocally.
6. A great facility of inspection of the grooves a b d. It is in fact sufficient to
remove the suction body A in order to have access to the said grooves.
7. The capability of adapting a similar steam pump body AGR to propellers
having a different delivery without other change than the replacement of the ring B
by another ring suited for the new propeller.
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. A helico-centrifugal pump with a casing on the propeller, characterised by
the use of a removable ring (B) in the form of a hollowed out ajutage penetrating
into the interior of the suction body (A) by means of which ajutage the propeller
draws water into said suction body, the said removable ajutage (B) being capable
of being replaced by others having larger or smaller suction orifices which enables
propellers of larger or smaller discharge to be fitted to the same pump body (A GR)
by simply changing the ring ajutage (B), substantially as described.
2. A pump such as hereinbefore described, characterised by the arrangement
between the small base (E) of the casing (C) of the propeller (P) and the ajutage
ring (B), of a peculiar system of caulking obtained by providing the opposite
faces (E B) with a series of deep circular and concentric grooves having lateral

page_text: cylindrical walls (a bd) arranged in such a way that each ring produced between
two consecutive grooves of the said ring B fits into an opposite groove of the said
small base (E) and vice versa, such fitting being made with a slight lateral play and
longitudinal play sufficient to render easy the mounting and regulating of the pro-
peller substantially as described.
3. A connected pump with central box (MM) coupling two pumps such as
hereinbefore described characterised by the arrangement of central sleeve (D) fitted
in the central coupling box and having passages (r) placing the end chamber (S)
in communication with the pump (P¹) substantially as described.
Dated this 6th day of December 1897.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Agents for the Applicant.