[0001] The present finding refers to improvements made to sets for generating current in
generals, be they fixed or mobile.
[0002] More specifically, it concerns a system for silencing said current generator sets.
[0003] These generator sets, a typical use of which is in emergencies, for example to provide
electrical energy to the essential apparatuses of a hospital in the case of a black-out,
briefly comprise an electrical machine, like an alternator, which is driven by a combustion
engine, generally a Diesel-cycle internal combustion engine, all being installed on
a suitable platform.
[0004] The internal combustion engine is generally cooled by water, which flows in a radiator
that is crossed by a flow of air driven by a fan controlled by the engine, and intended
to cool down both the engine and the alternator. During operation, such generator
sets are generally rather noisy and therefore there is a requirement to cut out or
reduce as much as possible its noisiness, without of course altering the characteristics
of the overall cooling system for obvious reasons.
[0005] The main purpose of the finding is, indeed, that of providing a silencing system
for such generator sets that is able to fulfil the quoted requirement.
[0006] Another purpose of the finding is that of making a sound-proofing system that, as
well as having excellent silencing properties, allows access to the various parts
of the generator set, for example for control and maintenance interventions, both
general and specific, in a particularly simple, quick and easy manner.
[0007] A further purpose consists of making a sound-proofing system capable of achieving
the quoted goals in the context of a simple, rational, functional, strong and cost-effective
constructive solution.
[0008] Said purposes are achieved thanks to the characterising elements indicated in the
main claim.
[0009] Preferred and advantageous embodiments are outlined in the dependent claims.
[0010] In a totally general manner, said generator set is of the type outlined in the preamble,
or rather it comprises an internal combustion engine that is fitted onto a platform,
and at the opposite axial ends of which are associated a current generator and a cooling
fan suitable for creating a flow of fresh air that flows generally according to the
direction taken up by the axis of the engine, typically in the direction that goes
from the current generator to the cooling fan.
[0011] In accordance with the finding, said platform is provided with an overlying generally
parallelepiped sound-proofing shell that provides, at the bottom, a surrounding case
that contains the engine and its additional parts, and takes care of channelling the
cooling air flow, and at the top, a service chamber that provides two manifolds for
fresh air and exhaust air, respectively, the first of which places the outside in
communication with the underlying area of the case intended for the current generator,
and the second of which places the underlying area of the case intended for the fan
in communication with the outside.
[0012] Preferably, the flow of air between case and manifolds takes lace through a horizontal
wall that separates case and chamber.
[0013] Said horizontal wall preferably consists of a sound-absorbing baffle.
[0014] Thanks to the structure outlined above, the set is practically completely surrounded
by a sound-proofed jacket, obviously apart from the ports for the passage of fresh
air coming in and exhaust air going out, respectively, which allows a drastic reduction
in noise as has been able to be seen following specific tests carried out on various
types of generator sets, obviously tested with and without the silencing system according
to the finding.
[0015] The same tests have also allowed the excellent cooling characteristics of the generator
set thus jacketed to be detected.
[0016] Moreover, said sound-proofed shell preferably consists of a box-shaped body that
is open at the bottom suitable for resting on the engine-carrying platform, and removably
fixed there through threaded members so as to totally uncover the engine in a short
space of time.
[0017] Advantageously, said box-shaped body has hatches and removable panels intended for
localised interventions.
[0018] Thanks to the special characteristics indicated above all of the purposes of the
finding are thus achieved.
[0019] The characteristics and constructive advantages of the finding shall become clear
from the following detailed description, given with reference to the figures of the
attached tables of drawings that illustrate a particular and preferred embodiment
thereof, purely as an example and not for limiting purposes, and where:
Fig. 1 is a perspective view that shows the finding from the fresh air entry side.
Fig. 2 is a view totally similar to the previous one that shows the finding from the
exhaust air exit side.
Fig. 3 is an enlarged transparent view obtained according to the direction III indicated
in Fig. 2.
Fig. 4 is the section IV-IV indicated in Fig. 3.
[0020] From the quoted figures a strong metal platform 1 can be seen (figs. 1 to 3) on which
a generator set is installed.
[0021] It should be specified that the platform 1 can be of the type intended to be fixed
to the floor, or of the type suitable for being arranged on a mobile, self-propelled
or dragged means.
[0022] The generator set is of the known type and comprises, in short, an internal combustion
engine 2, generally with Diesel-cycle, which on one side (on the left in fig. 3) is
kinematically coupled with a current generator 3, typically an alternator, and on
the other side (on the right in the same figure) is kinematically connected to a fan
4 with a radiator 5 in front for circulating the cooling water for the engine 2.
[0023] With reference to the engine 2, the fan 4 creates a flow of air that generally runs
parallel to its axis in the direction that goes from the alternator 3 to the radiator
5 (see fig. 3).
[0024] The fresh air that reaches the generator set from the outside is indicated with A
in the figures, whereas the exhaust air that leaves the generator set and discharges
to the outside is indicated with B.
[0025] The elements making up the quoted generator set are received in the bottom part of
a generally parallelepiped insulated shell 6 with a rectangular plan (figs. 1, 2 and
4).
[0026] The shell 6 is open at the bottom so as to be able to be slotted from above onto
the platform 1, and be removably fixed there.
[0027] This takes place through a series of perforated ears 7 that stem from the lower edge
of the shell 6, and that carry respective locking through screws (see fig. 3). In
order to move the shell 6, once again see fig. 3, two lugs or handles 8 are foreseen
on top.
[0028] The same shell 6 is equipped with a horizontal separator baffle 9 (figs. 3 and 4)
that divides it into a bottom case 60 and a top chamber 66 communicating with each
other, where the first 60 encloses the generator set and the second 66 acts as a passage
for the respective flows of fresh air A and exhaust air B.
[0029] The side walls and the top of the shell 6, as well as the quoted separator baffle
9, individually consist of a generally cornice-shaped frame the port of which is buffered
by at least one sound-proofing sound-absorbing panel.
[0030] Between the top and bottom of said top chamber 66 a vertical dividing wall 10, consisting
of sheets of metal plate and sound-absorbing panels is arranged, which in plan (fig.
4) has a sinuate extension developing substantially according to a diagonal of the
shape in plan of said chamber 66.
[0031] In such a way the chamber 66 is divided into two areas that in plan have substantially
the shape of an elongated right-angled triangle extending generally parallel to the
axis of the underlying engine 2 (fig. 4).
[0032] One of said areas, the one in the top left in fig. 4, acts as a manifold for fresh
air A, and the other area, in the bottom right of the same figure, acts as a manifold
for exhaust air B.
[0033] In particular, the manifold for fresh air A communicates with the area of the case
60 intended for the alternator 3 (fig. 3) through a generally trapezium-shaped horizontal
opening 61 that is formed on the baffle 9 (fig. 4), and with the outside through a
vertical window 161 equipped with a grate (fig. 1).
[0034] Said horizontal opening 61 and said vertical window 161 are arranged in substantially
opposite positions with respect to the longitudinal development of the manifold for
fresh air A (fig. 3).
[0035] Similarly, the manifold for exhaust air B communicates with the area of the case
60 intended for the alternator 3 (fig. 3) through a rectangular-shaped horizontal
opening 62 that is formed on the baffle 9 (fig. 4), and with the outside through a
vertical window 162 equipped with a grate (figs. 2 and 3).
[0036] Said horizontal opening 62 and the respective vertical window 162 are arranged in
substantially opposite positions with respect to the longitudinal development of the
manifold for exhaust air B (fig. 3).
[0037] Moreover, to access the different parts of the generator set without having to remove
the shell 6 as explained previously, and to access the different inner areas of the
same shell 6, it is equipped with hatches and removable panels as is clearly illustrated
in figs. 1 and 2.
[0038] Finally, it is advantageously foreseen that the fuel tank, indicated with 20 in fig.
3, is removably arranged in a suitable side space formed on the platform 1. The special
characteristics and advantages of the finding can clearly be understood from the above
and from the examination of the attached figures.
1. Generator set, comprising an internal combustion engine (2) that is fitted onto a
platform (1), and at the opposite axial ends of which are associated a current generator
(3) and a cooling fan (4) suitable for creating a flow of fresh air that flows according
to the direction taken up by the axis of the engine, characterised in that said platform is equipped with an overlying sound-proofed shell (6) that provides,
at the bottom, a surrounding case (60) that contains the engine and its additional
parts, and takes care of channelling the flow of fresh air in transit, and at the
top a service chamber that provides two manifolds for fresh air and exhaust air respectively,
the first of which places the outside in communication with one end of the case, and
the second of which places the opposite end of the case in communication with the
outside.
2. Set according to claim 1, characterised in that the flow of the air between case and manifolds takes place through a horizontal wall
that separates said case and chamber.
3. Set according to claim 2, characterised in that said horizontal wall consists of a baffle with sound-absorbing properties.
4. Set according to claim 1, characterised in that said manifolds are separated by a vertical divider wall arranged between the top
and the bottom of said chamber.
5. Set according to claim 4, characterised in that each of said manifolds has, at one end, a horizontal opening formed on the bottom
of said chamber and opening into the case below, and, at the opposite end, a vertical
window communicating with the outside that is formed on the side wall of the chamber.
6. Set according to claim 5, characterised in that said dividing wall consists of a structure with sound-absorbing characteristics.
7. Set according to claim 1, characterised in that said shell consists of a substantially parallelepiped hollow body that is open at
the bottom which is slotted from above onto the platform, and is removably fixed here
through threaded members.
8. Set according to claim 7, characterised in that said hollow body is equipped with at least one upper handle for lifting and manoeuvring.
9. Set according to claim 7, characterised in that said hollow body is equipped with hatches and removable panels intended for access
to specific parts of the generator set and/or inner areas of the respective shell.
10. Set according to claim 1, characterised in that the platform is equipped with a space that is accessible from the outside where the
fuel tank for said internal combustion engine is removably received.