[0001] The present invention concerns a fastening system of an exhaust group to a scooter.
[0002] In the field of two-wheeled vehicles known as scoters, the engine is typically an
integral part of the rear fork that in such a way makes the rear suspension.
[0003] According to the aforementioned solution the engine is "hinged" to the frame and
oscillates with respect to it about a centre of rotation.
[0004] In this type of embodiment, the muffler is therefore installed integrally to the
engine, fixing the manifold of the muffler to the exhaust hole present on the engine,
whereas the end part thereof is fixed to the engine by means of a rear suspension
element. Such a suspension element is, in general, also used for the attachment of
the shock absorber.
[0005] In this way, the muffler, like the engine, also has an oscillating movement with
respect to the frame and, consequently, the entire exhaust system increases the so-called
"non-suspended mass" of the vehicle.
[0006] In other words, this is the mass of the components of the vehicle integral with the
wheels.
[0007] Therefore, a distribution of the masses is created that is particularly disadvantageous
from the point of view of rider comfort, meaning the degree of transmission to the
rider, through the interface points (handlebars, foot rest, seat), of the vibrations
originating from the unevenness of the road surface.
[0008] In some cases, rider comfort can even reach critical levels also from the point of
view of safety.
[0009] In light of the above, there is clearly a need to be able to have a fastening system
of an exhaust group to a scooter that ensures that most of the mass linked to the
exhaust system, integral with the oscillating engine, is transformed into suspended
mass improving rider comfort.
[0010] Therefore, the purpose of the present invention is that of solving the problems of
the prior art by providing a fastening system of an exhaust group to a scooter that
allows the non-suspended masses to be reduced and allows the suspended masses of the
vehicle to be increased, at the same time improving rider comfort.
[0011] Another purpose of the present invention is that of providing a fastening system
of an exhaust group to a scooter that allows the transmission of the vibrations generated
by the unevenness of the road surface in the interface points between vehicle and
rider to be decreased.
[0012] Another purpose of the present invention is that of providing a reliable and safe
fastening system of an exhaust group to a scooter that is, at the same time, easy
and cost-effective to produce.
[0013] These and other purposes are accomplished by the fastening system of an exhaust group
to a scooter according to the present invention that has the characteristics of the
attached claim 1.
[0014] Substantially, a fastening system of an exhaust group, comprising at least one muffler
and at least one manifold pipe to a scooter according to the present invention is
characterised in that it comprises at least one flexible coupling, arranged between
the muffler and the exhaust hole of the engine, and attachment means suitable for
connecting the muffler to the frame of the scooter.
[0015] Further characteristics and advantages of the present invention shall become clearer
from the following description, given for illustrative and not limiting purposes,
with reference to the attached drawings, in which:
- figure 1 shows a side view of the rear of a scooter equipped with the fastening system
of the exhaust group according to the present invention;
- figure 2 shows an enlarged partial perspective view of a detail of the fastening system
of an exhaust group to a scooter according to the present invention;
- figure 3 shows an enlarged view of the attachment means of the muffler to the frame
of a scooter according to the present invention; and
- figure 4 shows a side view of the rear of a scooter equipped with a second embodiment
of the fastening system of the exhaust group according to the present invention;
[0016] With reference to the figures, a fastening system of an exhaust group, equipped with
at least one muffler 2 and with at least one manifold pipe 3', 3, 4, to a scooter
10 is shown.
[0017] The fastening system, according to a preferred embodiment, shown in figures 1 to
3, has a flexible coupling 5, arranged between the muffler 2 and the exhaust hole
6 of the engine 7, and suitable attachment means 8 suitable for connecting the muffler
2 to the frame 9 of the scooter.
[0018] In detail, the attachment means 8 are arranged to fasten the muffler 2, near to its
rear portion, to the end portion of the frame 9.
[0019] Advantageously, according to the present embodiment, the attachment means 8 are represented
by a first bracket 14, integral with the muffler 2, by a second bracket 15, integral
with the frame 9, and by a support arm 16, hinged to both of the brackets 14, 15.
[0020] In detail, the support arm 16 is hinged, through known means such as screws and bolts,
at one end to the first bracket 14 and at the other end to the second bracket 15.
[0021] Alternatively, the support arm 16 could be integral with the frame 9, in other words
made as a projecting portion of the frame itself, and hinged at the free end to a
bracket integral with the muffler 2.
[0022] In a further embodiment, the suspension arm 16 can be integral with the muffler 2
and be hinged to a bracket integral with the frame 9.
[0023] Returning to the preferred embodiment, shown in figures 1-3, it is revealed that
the flexible coupling 5 is connected and arranged between a first 3 and second 4 manifold
pipe.
[0024] In detail, the first manifold pipe 3 connects the coupling 5 to the exhaust hole
6 of the engine 7, whereas the second manifold pipe 4 connects the coupling 5 to the
muffler 2.
[0025] On the second manifold pipe 4, as shown in figure 1, there is a flanged portion 17
suitable for coupling, through known means such as screws and bolts, with a corresponding
flanged portion 18 of the muffler 2.
[0026] According to the present invention, the flexible coupling 5 is positioned near to
the centre of rotation 11 of the engine 7 with respect to the frame 9 so as to reduce
possible ripping away on the coupling itself, whilst the scooter 10 moves.
[0027] A flexible coupling particularly suitable for the purpose is described in patent
EP0083910 to Tubiflex S.p.A.
[0028] To protect the flexible coupling from dangerous relative torsions between the manifold
pipes 4 and 5, protective elements 12, 13 are foreseen, at least one of which is hinged
on the centre of rotation 11 of the engine 7 with respect to the frame 9.
[0029] The two protective elements 12, 13 partially wrap around the flexible coupling 5
and the end portions of the manifold pipes 3 and 4 and are shaped to protect the coupling,
as well as from torsions, also from relative axial and lateral movements of the manifold
pipes 3 and 4.
[0030] In figure 4 an alternative embodiment of the present invention is shown that is totally
similar to the one illustrated in figures 1 to 3 apart from the fact that it has just
one manifold pipe 3' and attachment means 8 of the muffler 2 to the alternative frame
9.
[0031] In detail, the manifold pipe 3' is connected at one end to the exhaust hole 6 of
the engine 7 and at the other end to the flexible coupling 5.
[0032] The flexible coupling 5, as shown in figure 4, is directly connected to the muffler
2.
[0033] Also according to this embodiment, the flexible coupling 5 is positioned at the centre
of rotation 11 of the engine 7 with respect to the frame.
[0034] The attachment means 8, as shown in figure 4 according to the present embodiment,
comprise a first bracket 14', integral with the muffler 2, hinged directly to the
frame 9 of the scooter 10.
[0035] The fastening system of the exhaust group to the scooter according to the present
invention allows the mass of the exhaust group to be transformed from non-suspended
mass into suspended mass, improving rider comfort.
[0036] In other words, the mass of the exhaust group is no longer, like in conventional
scooters, integral with the engine and with its oscillations with respect to the frame,
but is separate from it and from its oscillating movements, so as to be suspended
at the frame.
[0037] In such a way, the transmission of vibrations originating from the unevenness of
the road surface in the interface points between scooter and rider is reduced, increasing
rider comfort.
[0038] The present invention has been described for illustrating, but not limiting purposes,
according to its preferred embodiments, but it should be understood that variations
and/or modifications can be brought by men skilled in the art without for this reason
departing from the relative scope of protection, as defined by the attached claims.
1. Fastening system of an exhaust group, comprising at least one muffler (2) and at least
one manifold pipe (3, 4), to a scooter (10) characterised in that it comprises at least one flexible coupling (5), arranged between said muffler (2)
and the exhaust hole (6) of the engine (7), and attachment means (8) suitable for
connecting said muffler (2) to the frame (9) of the scooter (10).
2. Fastening system of an exhaust group according to claim 1, characterised in that said flexible coupling (5) is positioned near to the centre of rotation (11) of the
engine with respect to the frame (9) of the scooter (10).
3. Fastening system of an exhaust group according to any one of the previous claims,
characterised in that it comprises at least one protective element (12, 13), hinged to said frame (9) at
said centre of rotation (11) of the engine, suitable for protecting said flexible
coupling (5) and for avoiding dangerous movements of said flexible coupling (5).
4. Fastening system of an exhaust group according to any one of the previous claims,
characterised in that it comprises a first manifold pipe (3) connected to said exhaust hole (6) of the
engine (7) and to said flexible coupling (5) and a second manifold pipe (4) connected
to said flexible coupling (5) and to said muffler (2).
5. Fastening system of an exhaust group according to any one of claims 1 to 3, characterised in that it comprises a single manifold pipe (3') connected at one end to said exhaust hole
(6) of the engine and at the other end to said flexible coupling (5) in turn directly
connected to said muffler (2).
6. Fastening system of an exhaust group according to any one of the previous claims,
characterised in that said attachment means (8) comprise a first bracket (14) integral with said muffler
(2), a second bracket (15) integral with the frame (9) of the scooter and a connection
arm (16) hinged at one end to said first bracket (14) and at the other end to said
second bracket (15).
7. Fastening system of an exhaust group according to any one of the previous claims from
1 to 5, characterised in that said attachment means (8) comprise a first bracket (14') integral with said muffler
(2), hinged directly to said frame (9) of the scooter.
8. Scooter characterised in that it comprises a fastening system of an exhaust group to the scooter according to any
one of the previous claims.