[0001] The present invention relates to a pumping unit usable in liquid distribution systems,
such as drinking water distribution systems, fire-fighting systems, garden or agricultural
irrigation systems and vehicle wash systems.
[0002] For the aforestated uses electric pumps of so-called surface type are currently used.
These electric pumps present various drawbacks. In particular, their electric motor
is provided with a cooling fan which is particularly noisy and can disturb those in
the vicinity of the room in which these pumps are located. Moreover, for evident reasons
the said room has to be aerated, hence non-aerated rooms cannot be used. Again, these
pumps require a bed on which they are fixed. A further drawback derives from the fact
that the electric motor is provided with so-called pre-lubricated bearings which,
however, after a determined time period have to be replaced.
[0003] Electric pumps of the aforesaid type are known having an intake port and a delivery
port positioned coaxially one opposite the other (i.e. "in line"), hence these pumps
can be inserted directly into a straight pipe without using elbow connectors.
[0004] Submerged electric pumps in which the motor does not require a cooling fan have also
been known for some time. For this reason they are considerably less noisy than surface
electric pumps, and do not require aeration or maintenance. However they have to be
located in a sump or be kept immersed in the liquid to be pumped.
[0005] It is also known to encase a submerged electric pump in a so-called booster, i.e.
a pipe piece acting as a container for the liquid in which the pump has to be immersed.
The booster is vertical and needs a suitable bed. The liquid inlet is directed horizontally
and lies in the lower part of the booster, while the outlet is provided at its upper
end and is directed vertically. In this case it is evidently not possible to mount
the booster in line with the relative submerged pump.
[0006] Arrangements are known in which the booster is disposed horizontally, supported by
suitable saddles or support rings. The liquid inlet and outlet are provided mutually
coaxial at the two ends of the booster, so that in this case in-line mounting is possible.
There remains however the drawback of the need for suitable supports and the fact
that the booster has a horizontal size equal to its length.
[0007] The object of the present invention is to provide a pumping unit which is decidedly
less noisy than conventional surface pumps, can be located in non-aerated rooms, does
not require a bed or support, can be mounted "in-line", and virtually requires no
maintenance.
[0008] This object is attained by the pumping unit of the present invention, comprising
an electric pump of submerged or submersible type inserted in a booster provided with
an inlet port and an outlet port for the liquid, these two ports both being located
at that end of the booster closer to the electric pump delivery, they facing opposite
directions and being aligned.
If the booster is disposed vertically, its lower end is conveniently shaped to be
able to rest directly on any floor, hence eliminating the need for a specific bed
or other support. However the booster can evidently be disposed horizontally if this
is preferable. Such an arrangement would require a support only at that end of the
booster opposite that in which the inlet and outlet ports are present.
[0009] Preferably the booster comprises a double jacket with the two jackets spaced apart.
The space between the two jackets can be filled with a sound-absorbent material.
[0010] From the aforegoing it is already apparent that the invention provides a pumping
unit which can be mounted directly "in-line", is extremely silent and, if the booster
is vertical, is of minimum plan dimensions. Known pumping units do not enable all
these results to be obtained simultaneously.
[0011] The invention will be more apparent from the ensuing description of one exemplifying
embodiment thereof. In this description reference will be made to the accompanying
drawings, in which:
Figure 1 is an elevation of a pumping unit of the present invention, shown in "in-line"
installation;
Figure 2 is a partly cut-away plan view from above showing the pumping unit alone;
Figure 3 is a vertical section therethrough on the line 3-3 of Figure 2;
Figure 4 is a partial vertical section therethrough on the line 4-4 of Figure 3;
Figure 5 is a plan view of a pumping assembly formed from a determined number of modular
pumping units identical to that of the preceding figs;
Figure 6 is an elevation of the pumping assembly in the direction of the arrow 6 of
Figure 5.
[0012] As can be seen from Figures 1-4, the pumping unit 10 comprises a conventional submerged
electric pump 12 (Figure 3) positioned coaxially within a booster 14. This latter
has an overall parallelepiped shape with a support foot 16 which closes its lower
end.
[0013] As can be seen from Figure 1, specific supports or a bed are not required for the
pumping unit 10 as it is simply rested on a floor 54, it being maintained in position
by the pipe 55 in which it is inserted "in-line". Even in the case of the pumping
assembly of Figures 5 and 6, it is sufficient simply to rest the various pumping units
10 directly on the floor 54, the connectors 56 and 58 plus the system headers 62 and
64 (provided with their supports 60) then being sufficient to maintain the individual
units 10 in position.
[0014] The lateral wall of the booster comprises two jackets, of which the outer 18 is for
example of anodized duralumin and the inner 20 is of stainless steel. The interspace
between the two jackets 18 and 20 can be filled with a conventional sound-absorbent
material, although good silencing levels are already obtained even if the interspace
is empty (i.e. containing air). From Figure 3 it can be seen that an anti-vibration
ring 22 is fixed to the internal jacket 20 to retain the lower end of the electric
pump 12, the rest of which is suspended by a connector 24 from a headpiece indicated
overall by 26 and fixed by screws to a connector element 42, itself fixed by screws
to the top of the booster 14. The headpiece 26 comprises, in one piece therewith,
both the inlet port 30 and the outlet port 28, with the relative connection channels.
[0015] With the electric pump 12 in operation, the liquid entering from the inlet port 30
flows through the inlet channel portion 32 which deviates it downwards, so that the
liquid flows between the outer lateral surface of the electric pump 12 and the inner
lateral surface of the booster 14, reaching the lower end of the electric pump 12,
to be then drawn through its intake port and leave through the said delivery connector
24, to flow through the outlet channel 34 which deviates the liquid in a horizontal
direction until it leaves from the outlet port 28. As can be seen, the inlet port
30 and the outlet port 28 are aligned on the same axis 36 and opposite to each other,
forming (considering that the electric pump is vertical) a T-shaped path of the liquid.
This enables the pumping unit 10 to be directly inserted into a pipe without having
to provide connection bends.
[0016] In the specific example illustrated, the pumping unit 10 also comprises a control
unit indicated overall by 44 located below the headpiece 26. The control unit 44 comprises
an electronic card 46 and a display 48, all enclosed in a casing 38 provided with
a removable cover 50. The casing 38 also contains an inverter 40 supported by the
headpiece 26 and connected to a pressure transducer 41. This latter enables the delivery
pressure to be measured and a signal to be fed to the inverter 40 to regulate the
operation of the motor of the electric pump 12, this enabling electrical energy to
be saved.
[0017] The unit 10 also comprises a level sensor 52 preventing the electric pump 12 from
operating under dry conditions.
From Figures 1-4 and from the preceding description it will be apparent that, in addition
to the aforespecified advantages, the pumping unit 10 is very compact, is of very
small overall plan dimensions, and presents a ""clean" appearance, and in any event
a decidedly more acceptable appearance than known pumping units with the same type
of use.
[0018] The pumping unit 10 can represent a modular unit with which the said pumping assembly
shown in Figures 5 and 6 can be formed, and which in this specific example comprises
five pumping units 10 and relative connectors 56 and 58, with the two headers 62 and
64. This arrangement makes it possible to provide a pilot pumping unit and arrange
that, if this latter develops a fault, another pumping unit of the assembly automatically
takes over as the pilot. The number of pumping units can obviously be different, according
to specific requirements and design choices.
1. A pumping unit (10) usable in liquid distribution systems, comprising an electric
pump (12) of submerged or submersible type inserted in a booster (14) provided with
an inlet port (30) and an outlet port (28) for the liquid, both (30, 28) being located
at that end of the booster (14) closer to the electric pump (12) delivery, and being
mutually opposite and aligned (along 36).
2. A pumping unit (10) as claimed in claim 1, wherein the booster (14) is disposed vertically
and has its lower end (16) shaped to be able to rest directly on a floor (54).
3. A pumping unit (10) as claimed in claim 1, wherein the booster (14) comprises a double
jacket, the two jackets (18, 20) being spaced apart.
4. A pumping unit (10) as claimed in claim 3, wherein the interspace between the two
jackets (18, 20) is filled with a sound-absorbent material.
5. A pumping unit (10) as claimed in claim 4, wherein the outer jacket (18) is of aluminium.
6. A pumping unit (10) as claimed in claim 4, wherein the inner jacket (20) is of stainless
steel.
7. A pumping unit (10) as claimed in claim 1, wherein the booster (14) is of overall
parallelepiped shape.
8. A pumping unit as claimed in claim 2, wherein an anti-vibration ring (22) is fixed
to the inner jacket (20) to retain the lower end of the electric pump (12).
9. A pumping unit (10) as claimed in claim 2, wherein the electric pump (12) is suspended
from a headpiece (26) fixed to the top of the booster (14), in the headpiece (26)
there being provided in one piece therewith both the inlet port (30) and the outlet
port (28), with the relative connection channels (32, 34).
10. A pumping unit (10) as claimed in claim 9, wherein a control unit (44) is provided.
11. A pumping unit (10) as claimed in claims 9 and 10, wherein the control unit (44) is
located above the headpiece (26).
12. A pumping unit (10) as claimed in claim 10, wherein the control unit (44) comprises
an electronic card (46) and a display unit (48).
13. A pumping unit (10) as claimed in claim 10, wherein a pressure transducer (41) and
an inverter (40) are provided, the pressure transducer (41) being arranged to measure
the delivery pressure and to feed a signal to the inverter (40) to hence regulate
the operation of the motor of the electric pump (12).
14. A pumping unit (10) as claimed in claim 13, wherein the inverter is supported by the
headpiece (26).
15. A pumping unit (10) as claimed in claim 2, wherein a level sensor (52) is provided
connected to the control unit (44) to prevent the electric pump (12) from operating
under dry conditions.