ROLL OVER VALVE
FIELD OF TECHNOLOGY
[0001] The present invention relates to fuel tank and, more particularly to roll
over valve.
BACKGROUND
[0002] In order to control evaporative emission, vehicles are generally equipped
with an evaporated fuel collecting system. The system typically involves an evaporated
fuel collecting device connected to the .fuel tank through a breather pipe and to engine
intake side through a purge pipe. Typically, a roll over valve is installed between the fuel
tank and the evaporated fuel collecting device to avoid the entry of liquid fuel into the
evaporated fuel collecting device.
[0003] A roll over valve is an angle responsive valve which remains open so long
as the vehicle is operating in the normal position (for example, a vertical position in case
of a two-wheeled vehicle). In a roll over event of the vehicle, the roll over valve operates
to close the conduit between the fuel tank and the evaporated fuel collecting device so
that the fuel does not leak through the breather pipe into the evaporated fuel collecting
device. In the conventional systems, when the vehicle is brought into the upright position
after it is rolled over, the fuel left in the breather pipe enters the evaporated fuel
collecting device.
[0004] Existing roll over valves are complex and difficult to mount inside the
fuel tank, particularly at the opening of the breather tubc inside the fuel tank. Further,
there is a cost constraint involved in designing such roll over valves, and moreover the
conventional roll over valve system is not simple in configuration.
SUMMARY
[0005] In an embodiment, a fuel tank breathing system of a vehicle comprises a
breather tube and a roll over valve. The breather tube is disposed in a fuel tank of a
vehicle. The breather tube comprises a first end portion and a second end portion, where
the first end portion is disposed substantially horizontal in a longitudinal direction of the
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vehicle within the fuel tank, and the first end portion comprises a vent hole. The roll over
valve prevents liquid fuel from the fuel tank to enter the breather tube through the vent
hole in a roll over event of the vehicle. The roll over valve comprises a rotating element
rotatably mounted within the first end portion of the breather tube. The rotating element
has a cylindrical cross section comprising an arc segment such that a .gap segment is
created inside the breather tube between the arc segment and an inner surface of the
,breather tube. The roll over valve also comprises an oscillating element coupled with the
rotating element, where the oscillating element is configured to maintain a substantially
vertical position. During a normal operating condition of the vehicle, the rotating
element coupled with the oscillating element is aligned within the first end portion of the
breather tube such that the ,gap segment is upward of the vent hole for maintaining
communication between the fuel tank and the breather tube. Further, upon occurrence of
I the roll over event of the vehicle, a relative rotation between the rotating element and the
breather tube causes the arc segment to overlap with the vent hole thereby temporarily
sealing the vent hole to prevent.comrnunication of the liquid fuel from the fuel tank to
the breather tube.
[0006] In an embodiment, the oscillating element is positioned outside of the
breather tube in a pendulum like arrangement and is connected to the rotating element
via a connecting means such as a metallic wire. In an embodiment, the fuel tank
breathing system fiu-ther comprises a cap for closing an opening of the first end portion
of the breather tube. The cap comprises a provision for passing the connecting means
therethrough.
[0007] In an embodiment, an intermediate portion of the rotating element
comprises a notch for allowing the evaporated fuel to enter the breather tube.
[0008] In an embodiment, the rotating element is made up of at least one of a
rubber and a metal.
[0009] In another embodiment, a fuel tank breathing system of a vehicle
comprises a breather tube and a roll over valve. The breather tube is disposed in a fuel
tank of the vehicle. The breather tube comprises a first end portion comprising a vent
hole and a second end portion. The roll over valve prevents liquid fuel from the fuel tank
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to enter the breather tube in a roll over event of the vehicle. The roll over valve
comprises a clamping element, a first arm, a second arm and a wire. The clamping
element is of a substantially circular arc shaped structure comprising a first end and a
second end. The clampihg element is rotatably partially circumscribing the first end
portion of the breather tube such that the vent hole is capable of being exposed. The first
arm extends from the first end and the second arm extends from the second end. The
wire is connected between a lower portion of the first suln and a lower portion of the
second arm: The wire is configured to extend from the lower portion of the first arm to
the lower portion of the second arm by transversely piercing through a ball. During a
normal position of the vehicle, the ball is configured to be in a substantially intermediate
position along a length of the wire between the first arm and the second arm thereby
facilitating the clamping element to expose the vent hole for maintaining communication
1 between the fuel tank and the breather tube. Upon occurrence of the roll over event of the
vehicle, the ball is configured to slide on the wire towards one of the first arm or the
second arm from the substantially intermediate position and the sliding of the ball causes
the clamping element to rotate around the first end portion of the breather tube thereby
blocking the vent hole for temporarily sealing the vent hole to prevent communication of
the liquid fuel from the fuel tank to the breather tube.
[0010] In an embodiment, the wire is aligned in a transverse axis ,of the vehicle
for enabling the ball to slide along the length of the wire when the roll over event is in a
left direction or a right direction.
[0011] In an embodiment, the breather tube is coupled with a tube main body of a
kel filler structure of the fuel tank using at least one bracket. In an embodiment, the fuel
tank,breathing system further comprises an evaporated fuel collecting device connected
to the second end portion of the breather tube for collecting evaporated fuel generated
fiom within the fuel tank.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The invention itself, together with further features and attended
advantages, will become apparent from consideration of the following detailed
description, taken in conjunction with the accompanying drawings. One or more
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embodiments of the present invention are now described, by way of example only, with
reference to the accompanying drawing wherein like reference numerals represent like
elements and in which:
[0013] Figure 1 illustrates a side view of a fuel tank of a two-wheeled vehicle
according to a1 embodiment of the present invention;
[0014]. Figlire 2 illustrates a rear view of the fuel tank with a fuel filler structure
of the two-wheeled vehicle according to an embodiment of the present invention;
[0015] .Figure 3 illustrates another view of the fuel tank of the two-wheeled
vehicle according to an embodiment of the present invention;
[0016] Figure 4 illustrates an enlarged view of the fuel filler structure fitted with
a breather tube according to an embodiment of the present invention;
[0017] Figure 5 illustrates enlarged view of a portion of the breather tube
according to a first embodiment of the present invention;
[0018] Figure 5A illustrates another enlarged view of a portion of the breather
tube according to the another embodiment of the present invention;
[0019] Figure 6 illustrates a cross sectional view of the breather tube according to
the first embodiment of the present invention;
[0020] Figure 6A illustrates a cross sectional view of the breather tube according
to the another embodiment of the present invention;
[0021] Figure 7 illustrates an enlarged side view of the fuel filler structure fitted
with a breather tube according to a second embodiment of the present invention;
100221 Figure 8A illustrates an enlarged portion of the breather tube provided
with a clamping member in a normal condition of the vehicle according to the second
embodiment of the present invention;
[0023] Figure 8B illustrates an enlarged portion of the breather tube povided
with a clamping member during the vehicle rolling over situation according to the second
embodiment of the present invention; and
[0024] Figure 8C illustrates an enlarged portion of the breather tube provided
with the clamping member in the rolled over colidition of the vehiclc according to the
second embodiment of the present invention.
[0025] The drawings referred to in this' description are not to be understood as
being drawn to scale except if specifically noted, and such drawings are only exemplary
in nature.
DETAILED DESCFUPTION
[0026] While the invention is susceptible to various modifications and alternative
forms, specific embodiment thereof has been shown by way of example in the drawing
and will be described below. It should be understood, however that it is not intended to
limit the invention to the particular forms disclosed, but on the contrary, the invention is
to cover all modifications, equivalents, and alternative falling within the spirit and the
scope of the invention.
[0027] The terms "comprises", "comprising", or any other variations thereof, are
intended to cover a non-exclusive inclusion, such that a setup, device or method that
comprises a list of components or steps does not include only those components or steps
but may include other components or steps not expressly listed or inherent to such setup,
device or method. In other words, one or more ele~iiellts in a system or apparatus
proceeded by "comprises.. . a" does not, without more constraints, preclude the existence
of other elements or additional elements in the system or apparatus.
[0028] It is to be noted that terms such as "two-wheeled vehicle" and "vehicle"
are interchangeably used throughout the description. The term "two-wheeled vehicle"
includes vehicles such as motorcycles, scooters, bicycles, mopeds, all terrain vehicles
(ATV) and the like. Further, the terms "front 1 forward", "rear 1 rearward I back 1
backward", "up 1 upper 1 top I upward", "down 1 downward 1 lower 1 lowenvard", "left 1
leftward", "right I rightward" used therein represents the directions as seen from a
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vehicle driver sitting astride. Particularly, the directions "up / upper / top / upward",
"down. / downward / lower / lowerward", "left / leftward" and "right / rightward" are
referred by arrows U, Lr, L, R, respectively in one or more of the drawing figures.
[0029] For the better understanding of this invention, reference would now be
made to the embodiments illustrated in greater depth in the accompanying figures and
description hereinbelow, further, in the following figures, the same reference numerals
are used to identify the same components in various views.
[0030] Figure 1 and Figure 2 illustrate a side view and a rear view of a fuel tank
(100) of a two-wheeled vehicle according to an embodiment of the present invention.
The fuel tank (100) as per the preferred embodiment includes a tank body (122) and a
bottom member (123), where the tank body (122) and the bottom member (123) are fixed
to each other such that a sealed closed space (described later) is formed. The fuel tank
(100) has a shape which is elevated at its frontal portion, as compared to its rear portion
so as to maintain the streamlined body structure. Furthermore, the lower portion of the
fuel tank (100) is formed in a bifurcated shape so as to enable the straddling frame
element existing in the centre of vehicle body.
[0031] As depicted, the tank body (122) includes a top wall (101) and side walls
(1 02A) and (1 02B) extending downwardly from the top wall (1 01). The bottom member
(1 23) comprises bottom walls (1 03A) and (1 03B) 'and a tunnel wall (1 04). The bottom
walls (103A) and (103B) extend towards each other from the side walls (102A) and
(1 02B), and the tunnel wall (1 04) extends between the bottom walls (1 03A) and (1 03B)
to 'define an inverse U-shaped cavity (105) of the fuel tank (100). The inverse U-shaped
cavity (105) is formed along a longitudinal direction of the fuel tank (100). In the
illustrated construction, the top wall (101) and the side walls (102A) and (102B) form
aesthetic shape of the fuel ,tank (100) and are contoured accordingly. It should be
understood that shapes of the fuel tank (100) may vary and such shapes are often selected
to achieve desirable aesthetic appearances.
[0032] The fuel tank (100) has an enlarged forward end (107) and a tapered
rearward end (108) (visible in Figure 3). As depicted in Figure 2, the top wall (101), side
walls (102A) and (102B), the bottom walls (1 03A) and (103B) and the tunnel wall (104)
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are joined to define a sealed closed space to be used as a fuel chamber (1 11) with the file1
chamber (1 11) having a first side (1 12) and a second side (1 13). The inverse U-shaped
cavity (105) extends between the first side (1 12) and the second side (1 13) of the fuel
tank (100). The inverse U-shaped cavity (105) forms part of the fuel tank (100) that
straddles along a main frame of the two-wheeled vehicle.
[0033] With reference to Figure 3, the tank body (122) on its top wall (101) is
crowned to form a fuel cap opening portion (124). The fuel cap opening portion (124) is
equipped with a fuel filler structure (1 18), where the fuel filler structure (1 18) is
provided with an opening in its central region. In an embodiment, the fuel filler structure
(1 18) is welded to the fuel cap opening portion (124) of the fuel tank (100). The fuel
filler structure (1 18) has an opening portion (129) and can be closed by a removable tank
cap (not shown).
1 [0034] With reference to Figure 4, the fuel tank (100) is normally provided with
a breather tube (1 19) for the purpose. of allowing fuel vapour to escape from the fuel tank
(100). The breather tube (1 19) is provided in the proximity of a tube main body (1 3 1) of
the fuel filler structure (1 18). A first end portion (135) of the breather tube (1 19) is
provided along a longitudinal direction of the vehicle and is located at a relatively high
position inside the fuel tank (100). The -first end portion (135) is substantially horizontal
within the fuel tank (1 00). A second end portion (1 33) of the breather tube (1 19) may be . .
outside of the fuel tank (135) and communicates with an evaporated fuel collecting
device (130) for adsorbing fuel vapours and diverting it to the intake system of the
internal combustion engine by suitable means.
[0035] . When the fuel tank (100) is filled up with fuel, the fuel vapours are
lbb. trapped in an upper portion of the fuel tank (100) in which the first end portion (135) of
the breather tube (1 19) opens. In a roll over event of the vehicle, the fuel tank (100) rolls
over towards left or right direction beyond a predetermined angle. In such a scenario,
. there is a possibility of liquid fuel entering the breather tube (1 19) which may deteriorate
the. performance of the evaporated fuel collecting device (130), however various
embodiments of the present invention preclude such undesired entry of the liquid fuel in
the breather tube (1 19) as described later in the present description.
[0036] Figure 5 illustrates an enlarged side view of the breather tube (1 19)
according to a first embodiment of the present invention. The breather tube (1 19) on its
first end portion (135) is provided with a vent hole (136) on its lower surface. The
breather tube (1 19) is further provided with a rotating element (137) that is rotatably
mounted in the breather tube (1 19): More specifically, the rotating element (137) is
rotatably arranged within the first end portion (135) of the breather tube (1 19). For
example, the rotating element (137) is arranged along the length of the first end portion
(135) which is substantially horizontal within the fuel tank (100). An oscillating element
(1 43) is connected to the rotating element (1 37) through a connecting means (1 44). In an
example, the rotating element (137) is made up of rubber. In another example, the
rotating element (137) is made up of metal. Moreover, the rotating element (137) may be
made up of other kinds of suitable materials as well apart from rubber and metal.
[0037] As per 'the first embodiment depicted in Figure 5 and Figure 6, the
rotating element (137) is cylindrical in shape with circular segment like configuration
and comprises a solid arc segment (138). A gap segment (139) is created inside the
breather tube (1 19) between the solid arc segment (138) of the rotating element (137)
and the inner surface (134) (e.g., inner lower surface) of the breather tube (1 19). The
rotating element (137) is arranged along the length of the breather tube (1 19) such that
the rotating element (137) is rotatable along the longitudinal axis (A-A') (see, Figure 5)
of the first end portion (1 35) of the breather tube (1 19). Within the breather tube (1 19),
the rotating element (137) is so arranged that the gap segment (139) aligns upwards of
the vent hole (136) when the vehicle is in vertical or substantially vertical position.
Hence, in the vertical or substantially vertical position of the vehicle, the vent hole (136)
is in communication with the breather tube (1 19). The vent hole (136) gets sealed when
the arc segment (138) is overlapped with the vent hole (136) particularly in a scenario
when the roll over event of the vehicle occurs (described later).
[0038] The breather tube (1 19) on its surfaces proximal to the tube main body
(131) is.provided' with at least one bracket (145) to ensure the rigidness of the breather
tube (1 19) in terms of its alignment and position with respect to the fuel filler structure
(1 18).
[0039] In another embodiment as depicted in Figure 5A and Figure 6A, the
rotating element (137) is cylindrical in shape and is arranged along the length of the
breather tube (1 19), particularly along the length of the first end portion (135) of the
breather tube (1 19) where the first end portion (135) is substantially horizontal. The
rotating element (137) in its intermediate portion along the length is provided with a
notch (141) for fuel vapour to enter the breather tube (1 19). The notch (141) is further
connected with a provision (142) running along the length of the rotating element (137)
and facilitates the charging of fuel vapours into the breather tube (1 19). *
[0040] To maintain the rotating element (137) within the breather tube (1 19), the
breather tube (1 19) is provided with a cap (140) to close an opening (146) of the first end
portion (1 35) of the breather tube (1 19). The cap (1 40) ensures that the rotating element
(137) remains rotatable within the breather tube (1 19). The cap (140) covers the opening
(146) of the first.end portion (135) of breather tube (1 19). The cap (140) has a provision
(not shown in Figures) to let the connecting means (144) pass therethrough. In an
embodiment, the connecting means (144) is made of metallic wire.
[0041] Referring to Figures 5 and 5A, the oscillating element (143) hangs from
the opening (146) of the first end portion (135) of the breather tube (1 19) in a pendulum
like arrangement. The oscillating element (143) is maintained in a substantially vertical
position irrespective of whether the vehicle is in the normal operating position or under a
roll over event. Hence, in the roll over event of the vehicle, there in a relative motion
between the rotating element (137) and the breather tube (1 19). For example, in the roll
over event of the vehicle, the orientation of the breather tube (1 19) changes and there is a
relative rotation of the rotating element (137) within the breather tube (1 19), and the
substantially vertical position of the oscillating element (143) is maintained within the
fuel tank (1 00).
[0042] During the normal operating condition (i.e. the normal position of the
vehicle) during running or standing, as per the first embodiment, the base segment or the
gap segment (139) of the rotating element (137) lies upwards of the vent hole (136)
provided on the bottom surface of the breather tube (1 19). In such a situation, there is no
physical contact between the rotating element (137) and the vent hole (136), and
communication between the file1 tank (100) and the breather tube (1 19) is maintained via
the vent hole (136). Furthermore, the oscillating element (143) lies hanging in a vertical
direction.
I [0043] During the banking of the vehicle in left/ right sides beyond a predetermined
angle, the oscillating element (143) tends to sway in the same direction in
which the vehicle falls down and such tendency of the oscillating element (143) causes
the rotating element (137) to rotate inside the breather tube (1 19) along the axis of the
breather tube (1 19). More specifically, there. is a relative rotation between the rul-ating
element (137) and the breather tube (1 19), and the relative rotation to a pre-determined
extent leads to the overlap of the arc segment (138) with the vent hole (136). As the arc
section of the arc segment (138) overlaps with the vent hole (136), the vent hole (136) is
temporarily sealed. The sealing of the vent hole (136) blocks the communication of the
fuel tank (100) with the breather tube (1 19), thus eliminating the risk of liquid fuel
entering the breather tube (1 19).
[0044] In the event of bringing the vehicle back from the rolled over position to
the normal position of the vehicle, the oscillating element (143) tends to move in the
same direction, and there occurs a relative rotation between the rotating element (137)
and the breather tube (1 19). Such relative rotation between the rotating elekent (137)
and the breather tube (1 19) causes the alignment of the gap segment (139) upwards of
the vent hole (1 36) thereby re-establishing the communication of the fuel tank (1 00) with
the breather tube (1 19) via the vent hold (136). It would be appreciated by those skilled
in the art that in the present embodiment, no liquid fuel is accumulated in the breather
tube (1 19) during the roll-over event, hence no liquid fuel is entered into the evaporated
fuel collecting device (130) when the vehicle is brought back to its normal position.
[0045] Figure 7 illustrates an enlarged side view according to second
embodiment of the present invention.
[0046] Referring to Figure 7 along with the Figures 8A, 8B and 8C, the breather
tube (1 19) towards its first end portion (135) is clamped with a clamping member (150)
comprising a first arm (151) a second arm (152) and a clamping element (153). More
specifically, the clamping element (153) is a substantially circular arc shaped structure
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HPO DELHI 18-04-2016 P7:3&
with its first end (156) extending as the first arm (151) and its. second end (157)
extending as the second arm (152). The first arm (151) and the second arm (152) are
connected to each other through an assembly of a ball (154) and a wire (155). The wire
(155) is configured to extend from a lower portion (see, 158) of the first arm (151) to a
lower portion (see, 159) of second arm (1 52) transversely piercing through the centre of
the ball (154). The wire (155) is connected to the first arm (151) and the second arm
(152) in the lower portions thereof.-In an embodiment, a thread of suitable material can .
be used instead of the wire (155). It will be understood by those skilled in the art that the
movement of the ball (154) along the length of the wire (1'55) towards either the first arm
(1 5 1) or the second arm (152) controls the gripping action of the clamping element (1 53)
over the breather tube (1'1 9).
[0047] As depicted in Figure 7 and Figure 8A, the first end portion (135) of the
breather tube (1 19) is mounted with the clamping element (1 53) and the integrated first
arm (1 5 1) and the second arm (1 52) hang down from the clamping element (1 53). The
clamping element (153) is arranged around the first end portion (135) of the breather
tube (1 19) in such a manner that the vent hole (1 36) is exposed and a communication is
established between the fuel tank (100) and the breather tube (1 19). For instance, the
clamping element (1 53) is rotatably partially circumscribing the first end portion (1 35) .of
the breather tube (1 19) such that the vent hole (136) is exposed for the intake of the
evaporated fuel. The wire (155) at one end is fixed to the first arm (151) and at other end
is fixed to the second arm (152). The ball (154) is slidable on the wire (155). The wire
(155) is aligned along the transverse axis of the vehicle to ensure movement of the ball
(154) along the length of the wire (155) when the vehicle rolls over in left or right
direction. In the normal operating condition (e.g., in the normal position of the vehicle),
the ball (154) lies at a substantially intermediate position along the length of the wire
(155). In the roll over event of the vehicle (e.g. when the vehicle rolls over in left or right
sides), the ball (154) moves towards the first arm (151) or the second arm (152)
depending upon the direction of vehicle roll over.
[0048] As depicted in Figure 8A, Figure 8B and Figure 8C, in the roll over event
of the vehicle in the left or right direction, the ball (154) slides on the wire (155)
corresponding to the direction of the vehicle roll over and moves along the length of the
.wire (1 55). The movement of the ball (1 54) causes the first arm (1 5 1) and the second
arm (152) to expand thereby rotating the clamping member (150) around the breather
tube (1 19). This rotation of the clamping member (1 50) blocks the exposure of vent hole
(136) to the fuel tank (100) thereby eliminating the risk of liquid fuel entering the
breather tube (1 19) in the roll over event of the vehicle.
[0049] Further, when the vehicle is brought back to its normal position from the
rolled over position of the vehicle, the ball (154) comes back to its almost intermediate
position along the length of the wire (155) thereby bringing the first arm (151) and the
second arm (1'52) back to their normal positions.
[0050] Various embodiments of the present invention provide a roll over valve in
a fuel' tank breathing system of a vehicle, where the roll over valve is capable of
eliminating the risk of liquid fuel entering a breather tube during any roll over event of
vehicle.
[0051] The roll over valves provided in the present invention offer cost effective
way of eliminating risk of liquid fuel entering into the breather tube during the roll over
event of the vehicle. Moreover, the examples of the roll over valves provided herein are
simple in construction.
[0052] Various embodiments of the present invention provide a fuel tank
breathing system designed to minimize the possibility of fuel entering into the breather
pipe during the rolling over of the vehicle beyond a predetermined angle.
[0053] While few embodiments of the present invention have been described
above, it is to be understood that the invention is not limited to the above embodiments
and modifications may be appropriately made thereto within the spirit and scope of the
invention.
[0054] While considerable emphasis has been placed herein on the particular
features of this invention, it will be appreciated that various modifications can be made,
and that many changes can be made in the preferred embodiments without departing
from the principles of the invention. These and other modifications in the nature of the
invention or the preferred embodiments will be apparent to those skilled in the art from
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the disclosure herein, whereby it is to be distinctly understood that the foregoing
descriptive matter is to be interpreted merely as illustrative of the invention and not as a
limitation.

CLAIMS
We claim:
1. A fuel tank breathing system of a vehicle, comprising:
a breather tube disposed in a fuel tank of the vehicle, the breather tube
comprising a first end portion and a.second end portion, the first end portion disposed
substantially horizontal 'in a longitudinal direction of the vehicle within the fuel tank,
the first end portion comprising a vent hole; and
a roll over valve for preventing liquid fuel from the fuel tank to enter the breather
tube through the vent hole in a .roll over event of the vehicle, the roil over valve
comprising:
a rotating element rotatably mounted within the first end portion of the
breather tube; the rotating element having a cylindrical cross section comprising
an arc segment such that a gap segment is created inside the breather tube
between the arc segment and an inner surface of the breather tube; and
an oscillating element coupled with the rotating element, the oscillating
element configured to maintain a substantially vertical position,
wherein during a normal operating condition of the vehicle, the rotating element
coupled with the oscillating element is aligned within the first end' portion of the
.breather tube such that the gap segment is upward of the vent hole for maintaining
communication between the fuel tank and the breather tube, and
wherein upon occurrence of the roll over event of the vehicle, a relative rotation
between the rotating element and the breather tube causes the arc segment to overlap
with the vent hole thereby temporarily sealing the vent hole to prevent communication
of liquid fuel from the fuel tank to the breather tube.
2. The fuel tank breathing system as claimed in claim 1, wherein the oscillating
element is positioned outside of the breather tube in a pendulum like arrangement and is
connected to the rotating element via a connecting means.
3. The fuel tank breathing system as claimed in claim 2, wherein the connecting
means is a metallic wire.
4. The fuel tank breathing system as claimed in claim 2 and further comprising a
cap for closing an opening of the first end portion of the breather tube, the cap
comprising a provision for passing the connecting means therethrough.
5. The fuel tank breathing system as claimed in claim 1, wherein an intermediate
portion of the rotating element comprises a notch for allowing evaporated fuel to enter
the breather tube. .
6. The fuel tank breathing system as claimed in claim 1, wherein the rotating
element is made up of at least one of rubber and a metal.
7. The fuel tank breathing system as claimed in claim 1, wherein the breather tube is
coupled with a tube main body of a fuel filler structure of the fuel tank via at least one
bracket.
8. The fuel tank breathing system as claimed in claim 1 and further comprising an
evaporated fuel collecting device connected to the second end portion of the breather
tube for collecting evaporated fuel from the fuel tank.
9. A fuel tank breathing system of a vehicle, comprising:
a breather tube disposed in a fuel tank of the vehicle, the breather tube
comprising a first end portion and a second end portion, the first end portion comprising
a vent hole; and
a roll over valve for preventing liquid fuel from the fuel tank to enter the breather
tube through the vent hole in a roll over event of the vehicle, the roll over valve
comprising:
a clamping element being of a substantially circular arc shaped structure
comprising a first end and a second end, the clamping element rotatably partially
circumscribing the first end portion of the breather tbbe such that the vent hole is
capable of being exposed;
a first arm extending from the first end;
a second arm extending from the second end; and
a wire connected between a lower portion of the first Arm and a lower
portion of the second arm, the wire configured to extend from the lower portion
of the first arm to the lower portion of the second arm transversely piercing
through a ball,
wherein during the normal position of the vehicle, the ball is configured to be in a
substantially intermediate position along a length of the wire betweei the first arm and
the, sec.ond arm thereby facilitating the clamping element to expose the vent hole for
maintaining communication between the fuel tank and the breather tube; and
wherein upon occurrence of the roll over event of the vehicle, the ball is
configured to slide on the wire towards one of the first arm or the second arm from the
substantially intermediate position, and wherein sliding of the ball causes the clamping
element to rotate around the first end portion of the breather tube thereby blocking the
vent hole for temporarily sealing the vent hole to prevent communication of the liquid
fuel from the fuel tank to the breather tube.
10. The fuel tank breathing system as claimed in claim 9, wherein the wire is aligned
in a transverse axis of the vehicle for enabling the ball to slide along the length of the
wire when the roll over event is in a left direction or in a right direction.
11. The fuel tank breathing system as claimed in claim 9, wherein the breather tube is
coupled with a tube main body of a fuel filler structure of the fuel tank via at least one
bracket.
12. The fuel tank breathing system as claimed in claim 9 and further comprising an
evaporated fuel collecting device connected to the second end portion of the breather
tube for collecting evaporated fuel from the fuel