[0001] The present invention relates to a device for supporting the motor unit of fans and
the like, particularly for filtering suction hoods.
[0002] In the above field it is known to use fans, for example of the centrifugal type,
which are constituted by an impeller driven by a corresponding motor unit inside a
suitable enclosure. A conventioal enclosure has a pair of mutually opposite heads
between which a jacket, forming a sort of volute, is fastened; these heads are formed
by rings of metal plate which are closed by respective grilles, made for example of
plastics, one of which supports the motor.
[0003] The generation of unpleasant vibrations is often complained about in the operation
of said suction elements. These vibrations are generally produced by impellers which
are not perfectly balanced and by defective driving shafts; the impellers can become
dirty over time, collecting grease particles, or deform due to the high temperatures.
[0004] The aim of the present invention is to solve the above-described problem, providing
a device for supporting the motor unit of fans and the like which can absorb any vibrations
that might be produced, so as to ensure silent operation.
[0005] Within the scope of this aim, an object of the present invention is to provide a
device for supporting the motor unit which is simple in concept, safely reliable in
operation and versatile in use.
[0006] This aim, these objects and others are all achieved, according to the invention,
by the present device for supporting the motor unit of fans and the like, of the type
comprising a grille which is suitable to be applied in a front region, along a peripheral
annular part, to a head of the enclosure of an impeller and forms, in a central region,
means for coupling to a motor unit of said impeller, which is supported in a cantilevered
manner inside said enclosure, which is characterized in that it comprises a vibration-damping
insert made of elastic material which is adapted to be interposed between said grille
and said head at said peripheral annular part, and is provided with flaps which protrude
transversely through corresponding slots formed in said head; and means for locking
said grille to said head which are adapted to be inserted through respective openings
formed in said grille, at said slots of said head, and to retain said flaps of said
vibration-damping insert on said head so as to wrap around said head in the fastening
position by acting from outside.
[0007] The details of the present invention will become apparent from the following detailed
description of a preferred embodiment of the device for supporting the motor unit
of fans and the like, illustrated only by way of non-limitative example in the accompanying
drawings, wherein:
Figure 1 is a partially cutout lateral view of the device according to the invention
for supporting the motor of a fan for filtering suction hoods;
Figure 2 is a sectional view of said device, taken along the plane II-II of Figure
1;
Figure 3 is a sectional view of a detail of said device, taken along the plane III-III
of Figure 1;
Figure 4 is an exploded perspective view of a portion of the device according to the
invention;
Figure 5 is a similar perspective view of a different embodiment of the device;
Figure 6 is a sectional view of another detail of the device, taken along the plane
VI-VI of Figure 2.
[0008] With particular reference to the above figures, 1 generally designates the device
for supporting the motor unit of fans and the like, particularly for filtering suction
hoods.
[0009] The device 1 has a grille 2, particularly made of plastic material, which is adapted
to be applied in a front region to a head 3 of the fan enclosure. The head 3 is conventionally
shaped, by a sheet metal ring which is shaped like a scroll and is surrounded by sides
4 and 5 along the outer and inner edges.
[0010] The grille 2 has a peripheral annular part 6 which is circular and is surrounded
by corresponding sides 7 and 8 which are directed toward the head 3, along the outer
and inner edges; the grille 2 forms, in a central region, a shaped portion 9 for the
coupling of the motor unit of the fan, which is not shown. In the illustrated case,
the coupling portion 9 is adapted to rigidly couple a motor having a rectangular profile;
however, the grille 2 may of course be provided so as to support motors having a different
shape, for example a circular or square one.
[0011] An insert 10, made of a material such as rubber and suitable to damp the vibrations
produced by the motor, is suitable to be interposed between the grille 2 and the head
3. The vibration-damping insert 10 is constituted by an annular element 11 which has
corresponding peripheral edges 12 and 13 which are directed toward the circular annular
part 6 of the grille 2 in the assembled position.
[0012] A series of prism-shaped protrusions 14 is formed along the annular element 11 of
the vibration-damping insert 10; said protrusions are evenly distributed and are directed
toward the head 3 in the assembled position. The protrusions 14 delimit corresponding
cavities 15 formed at the internal perimeter of the annular element 11 and are suitable
to wrap around corresponding raised portions 16 which are prism-shaped, in practice
rectangular, and are formed at the rim of respective openings 17 formed in the circular
annular part 6 of the grille 2.
[0013] The raised portions 16 are joined to the outer side 7 of the grille 2 by a series
of ribs or ridges 16a which are suitable to center the insert 10 and damp vibrations.
The ridges 16a engage a corresponding cavity 12a formed on the edge 12 of the insert
10 (reference should be made in particular to Figure 6).
[0014] In the illustrated case, the annular element 11 of the vibration-damping insert 10
covers the entire circumference and has protrusions 14 which are evenly distributed
along said circumference. However, it is possible to use individual inserts which
are localized at said raised portions 16 of the grille 2, each insert forming a corresponding
protrusion 14 which is shaped like the one that has already been described.
[0015] The head 3 in turn has, along the internal edge, a corresponding series of slots
18 which are adapted to wrap around respective protrusions 14 of the vibration-damping
insert 10. In practice, said protrusions 14 are clamped, in the assembled position,
respectively between the raised portions 16 of the grille 2 and the edge of the slots
18 of the head 3.
[0016] The protrusions 14 further have two transverse notches 19 which are suitable to delimit
a median portion 14a of said protrusions which substantially forms a flexible flap.
[0017] The grille 2 is meant to be locked to the head 3 by means of a plurality of step-shaped
brackets 20 which are inserted through said openings 17 formed in the grille 2 and
are fastened by means of corresponding screws 21 which screw into respective stubs
22 which are formed by said grille 2 along the inner side 8 at said openings 17.
[0018] The brackets 20 are adapted to fold said flaps 14a of the vibration-damping insert
10 onto the head 3, so as to wrap around said head 3 in the clamping position.
[0019] More specifically, the brackets 20 have, at their ends, respective portions 20a and
20b which are folded in a parallel arrangement on opposite sides; the first folded
portion 20a has a hole 23 for the insertion of the screw 21, while the second portion
20b is adapted to fold, in the assembled position shown by the dashed lines 20c in
figure 4, the flap 14a of the vibration-damping insert 10 onto the opposite head 3.
[0020] The operation of the device can be easily understood from the above description.
[0021] The vibration-damping insert 10 is interposed between the grille 2 and the metal
plate head 3 of the enclosure, taking care to fit the protrusions 14 on the corresponding
raised portions 16 of the grille 2 and to subsequently engage thereon the corresponding
slots 18 of the head 3.
[0022] It should be observed that the slots 18 formed on the head 3 also center said head
3 with respect to the grille 2 and prevent their mutual rotation.
[0023] In the assembled position, the flaps 14a formed by said protrusions 14 of the vibration-damping
insert 10 protrude transversely through said slots 18 of the head 3 (see Figure 2
in particular).
[0024] The respective locking brackets 20 are then inserted through the openings 17 of the
grille 2 by acting from outside. Said brackets 20 pass through the corresponding cavities
15 of the annular element 11 of the insert 10 and, by means of the folded portion
20b, fold the flaps 14a of said insert 10 against the head 3 (see also Figure 3).
[0025] The locking brackets 20 are then fastened to the grille 2 by means of the screws
21 which screw into the stubs 22.
[0026] In the locking position, essentially, the grille 2 that supports the motor is rigidly
coupled to the head 3 of the casing by interposing the vibration-damping insert 10
wrapping around said head 3 by means of the flaps 14a folded by the locking brackets
20. In other words, there is no direct contact of the sheet metal head 3 of the casing
with the grille 2 or with the brackets 20 that provide mutual locking, and this produces
an elastic support.
[0027] The vibration-damping insert 10 acts as a damping element for the vibrations produced
by the motor and by the elements connected thereto, particularly the impeller. Said
vibration-damping effect also affects axial rotation in the two opposite directions
and the radial direction, by virtue of the configuration of the protrusions 14 of
the insert 10 wrapping around the slots 18 of the head 3.
[0028] The vibration-damping insert 10 can of course be made of materials having different
rigidities according to the weight of the motor, so as to achieve the best damping
effect according to the specific requirements.
[0029] Said damping effect can also be adjusted appropriately by means of suitable washers
inserted between the folded portion 20a of the locking brackets and the corresponding
sleeves 22 so as to act as spacers. The insert is accordingly compressed more or less
intensely according to the thickness of said washers.
[0030] The outer edge 12 of the insert 10 also acts as a hermetic sealing element if a charcoal
filter or the like is applied to the grille 2 to form a filtering hood.
[0031] Figure 5 illustrates a different embodiment of the device, in which the means for
locking the grille 2 to the head 3 are constituted by a plate 24 which is provided
with a threaded stem 25 whereon a corresponding nut 26 is preassembled. The raised
portion 16 shaped on the grille 2 forms, in this case, a sort of hollow into which
the plate 24 is guided, causing in this case also the bending of the flap 14a of the
insert 10 so as to wrap around the head 3, providing a latch-like closure. The stem
25 of said plate 24 passes through a slot 27 formed on the bottom of said hollow.
[0032] As an alternative, the flaps 14a of the vibration-damping insert 10 can be provided
rigidly in said folded shape adapted to wrap around the head 3. In this case, of course,
the brackets 20 retain said flaps 14a in said fastening position.
[0033] The aim of the present invention is to provide the support of the motor unit of fans
and the like so as to damp any vibrations produced and thus ensure silent operation.
[0034] This aim is achieved in particular thanks to the fact that said brackets 20 or, as
an alternative, the plates 24 can be inserted after assembling the supporting elements
of the motor and the corresponding insert in the respective seat.
[0035] It should be observed that the device can be advantageously applied not only to the
above-mentioned centrifugal aspirators but also to helical and vane aspirators and
more generally to other similar industrial and civil applications and in different
fields, such as for example the automotive field, the air-conditioning field and the
like.
[0036] It should be observed that the device according to the invention allows to easily
lock the support of the motor by way of the locking means earlier described once said
motor has been arranged in its seat. Likewise, it is possible to perform release from
the outside.
[0037] This is particularly advantageous if the scroll-shaped head is small, as in the case
of hoods.
[0038] Furthermore the device is very sturdy and electrically very safe, when it uses plastics
elements, such as said grille, to support the motor, and in particular does not require
earthing.
[0039] In the practical embodiment of the invention, the materials employed, as well as
the shape and the dimensions, may be any according to requirements.
[0040] The disclosures in Italian Patent Application No. BO97A000526 from which this application
claims priority are incorporated herein by reference.
[0041] Where technical features mentioned in any claim are followed by reference signs,
those reference signs have been included for the sole purpose of increasing the intelligibility
of the claims and accordingly, such reference signs do not have any limiting effect
on the interpretation of each element identified by way of example by such reference
signs.
1. A device for supporting the motor unit of fans and the like, comprising a grille (2)
which is adapted to be applied in a front region, along a peripheral annular part,
to a head (3) of the enclosure of an impeller and forms, in a central region, means
(9) for coupling to a motor unit of said impeller, which is supported in a cantilevered
manner inside said enclosure, characterized in that it comprises a vibration-damping
insert (10) made of elastic material adapted to be interposed between said grille
(2) and said head (3) at said peripheral annular part and is provided with flaps (14a)
protruding transversely through corresponding slots (18) formed in said head (3);
and means (20,24) for locking said grille (2) to said head (3) which are adapted to
be inserted through respective openings (17,27) formed in said grille (2), at said
slots (18) of said head (3), and to retain said flaps (14a) of said vibration-damping
insert (10) on said head (3) so as to wrap around said head in the fastening position
by acting from outside.
2. The device according to claim 1, characterized in that said vibration-damping insert
(10) is constituted by an annular element (11) provided with respective prism-shaped
protrusions (14) which form said flaps (14a) and are adapted to delimit corresponding
cavities (15) formed in said annular element (11), at said openings (17,27) formed
in said grille (2).
3. The device according to claim 2, characterized in that said protrusions (14) of said
vibration-damping insert (10) are adapted to wrap around corresponding prism-shaped
raised portions (16) which are formed respectively at the edge of said openings (17,27)
formed in said grille (2).
4. The device according to claim 1, characterized in that said slots (18) of said head
(3) engage, in said locking position, corresponding prism-shaped raised portions (16)
formed by said grille (2), respectively at said openings (17,27), by way of the interposition
of corresponding protrusions (14) of said vibration-damping insert (10).
5. The device according to claim 1, characterized in that said means for locking said
grille (2) to said head have a series of step-shaped brackets (20) which are adapted
to be inserted through said openings (17) formed in said grille (2), so as to engage
said flaps (14a) of said vibration-damping insert (10), and are fastened through corresponding
screws (21) screwing into respective stubs (28) formed by said grille (2).
6. The device according to claim 5, characterized in that said brackets (20) have, at
their ends, respective portions (20a,20b) which are folded in parallel directions
on opposite sides and are meant respectively for the insertion of said screws (21)
and to retain said flaps (14a) of said vibration-damping insert (10) on said head
(3).
7. The device according to claim 1, characterized in that said means for locking said
grille to said head have a series of plates (24) which are respectively provided with
a threaded stem (25) whereon a corresponding nut (26) is preassembled, passing through
said openings (27) formed in said grille (2), said plates (24) being adapted to be
guided within a corresponding raised portion (16) which is shaped on said grille (2)
at said openings (27), so as to engage said flaps (14a) of said vibration-damping
insert (10).
8. The device according to claim 1, characterized in that said vibration-damping insert
(10) is constituted by a series of annular elements (11) provided with respective
prism-shaped protrusions (14) which form said flaps (14a) and are adapted to delimit
corresponding cavities (15) formed on said annular element (11) at said openings (17,27)
formed in said grille (2).