FIELD OF INVENTION
The present invention relates to fuel door position sensors and more
particularly to an apparatus, assembly and method for monitoring the closed position
of a fuel door and accordingly indicate the status of the fuel door by an audible/visual
warning indicator provided in a vehicle information display instrument of the
vehicles such as three wheelers, four wheelers, and the like.
BACKGROUND OF THE INVENTION
The statements in this section merely provide background information related
to the present disclosure and may not constitute prior art(s).
In a general trend, the automotive vehicles, running on liquid fuel, are
structured with a fuel tank provided to store the liquid fuel for supplying required
source of energy to the vehicles. These fuel tanks are typically designed with an
opening in a side thereof wherein a substantially cylindrical tube with a threaded end
is inserted into the opening and thus fixed to the fuel tank. The threaded end is
screwed by a fuel filler cap to control the vaporization and theft of the liquid fuel
from the fuel tank. The fuel filler cap is generally protected by a fuel tank door which
is pivotally connected to the extended portion of the cylindrical tube and biased in its
opening direction by a torsion spring. The fuel tank door is held closed by a locking
device that hooks on a protrusion formed on the inner surface of the fuel tank door.
The locking device is connected to an opening lever, provided beside the driver's seat,
by a cable such that the locking device unlocks if the driver pulls the opening lever to
open the fuel tank door.
In this way, its always a responsibility to close the fuel tank door after
refilling the fuel tank with the fuel. However, since the fuel tank door is opened from
within the vehicle and the same should be closed by a fuel service station attendant
(while refilling at a fuel station), the driver cannot always assure the closing of the
fuel tank door! This sometimes lead to driving of vehicle with the fuel tank door open
throughout the journey leading to the irritation of closing the fuel tank door midway.
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Further, the unclosed fuel tank door may lead to the theft of fuel too. Thus, the driver
may accidently run out of fuel if he relies on the fuel last noticed in the fuel tank.
Additionally, the liquid fuel, if left exposed, may vaporize and form fuel vapor
leading to unalarming loss of fuel.
Various automatic and manual attempts have been made in prior arts to
monitor the position of locking of the fuel tank door of the vehicles in case the fuel
tank door is either unclosed or partially closed. For instances, magnetic switches such
as reed switches are employed to read and sense the open and closed position of the
fuel tank door of the vehicles. However, while desirable from a performance and cost
point of view, the reed switches do not perform reliably over wide range of
temperature ranges, particularly at low temperature due to change in sensitivity of
reed switches at different temperatures. Further, the opening of the fuel tank door are
also sensed by limit switches that must be secured to the inside of the fuel tank during
manufacturing of the fuel tank. However, these limit switches may invite the chance
of spark and subsequent explosion if all the limit switches are not properly grounded
to the chassis of the vehicles. Furthermore, some vehicles are also provided with a
"Check Engine" warning indicator that is also an indication of opened fuel tank door
of the vehicle. However, "Check Engine" warning indicator is a broad indication of
any malfunctioning inside and related to the engine. Thus, the same excludes any
specific indication of fuel tank door unless specifically checked by mechanics or any
service bay, resulting in further enhanced cost.
Hence, there is an urgent need for a fuel tank door sensor that may overcome
the above mentioned drawbacks such as reliability over a wide range of temperature,
safety in terms of usage, cost effectiveness, accurate, customers' satisfaction and the
like. Importantly, there is a demand for the fuel tank door sensor that can read the
unclosed fuel tank door as well as partially closed fuel tank door of the vehicles.
BRIEF SUMMARY AND OBJECTIVES OF THE INVENTION
The present subject matter relates to a fuel tank door warning indicator for
automotive vehicles that basically includes a fuel tank to receive fuel via a fuel inlet,
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a thread ended cylindrical tube inserted into the fuel inlet, a fuel filler cap screwed on
the thread ended cylindrical tube and a fuel tank door pivotally connected to an
extended portion of the thread ended cylindrical tube to cover the fuel filler cap and
the fuel tank. The present subject matter uniquely discloses a locking device
projected as a movable protrusion integral to the inner surface of a lock plate
provided with the fuel tank wherein the locking device hooks on a protrusion formed
on the inner surface of the fuel tank door. Further, the arrangement is also provided
with a plunger body structured on interior of the lock plate in a way that the locking
device and the plunger body gets pushed by a ball type extrusion on closing the fuel
tank door wherein the fuel tank door warning indicator is actuated if the plunger body
remains non-pushed after closing the fuel tank door. The present subject matter
discloses a reliable, compact, less costly and a customer's friendly indicates unclosed
or partially closed fuel tank door warning indicator for automotive vehicles.
An object of the present subject matter is to design the fuel inlet as an opening
in a side thereof wherein substantially cylindrical tube with the threaded end is
inserted into the fuel inlet and thus fixed to the fuel tank.
An object of the present subject matter is to continuously push the plunger
body during the closed status of the fuel tank door.
An object of the present subject matter is to make the opening lever pulled by
the driver to open the fuel tank door.
An object of the present subject matter is to provide an audible fuel tank
warning indicator in automotive vehicles.
Yet another objective of the present invention is to provide an easy, compact,
less costly and advanced vehicle information display instrument wherein the
visual/audible fuel tank warning can be indicated. .
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BRIEF DESCRIPTION OF DRAWINGS
The summary narrated above and the following detailed description of the
invention can be understood with the drawings appended to this claim. The
illustrations provide the details of the invention. However, it should be understood
. that the invention is not limited to the arrangements shown. In the drawings:
FIG. 1 shows a perspective view of a four wheeler in an embodiment of the present
subject matter.
FIG. 2 illustrates a perspective view of a closed fuel tank assembly in an embodiment
of the present subject matter.
FIG. 3 illustrates a perspective view of an open fuel tank assembly in an embodiment
of the present subject matter.
FIG. 4 illustrates a perspective view of a arrangement of a fuel tank door in an
embodiment of the present subject matter.
FIG. 5 illustrates a perspective view of a plunger body in an embodiment of the
present subject matter.
FIG. 6 illustrates a cross sectional view of a plunger body in an embodiment of the
present subject matter.
FIG. 7 illustrates a view of a telltale for fuel tank warning indicator in a vehicle
information display instrument in an embodiment of the present subject matter.
DETAILED DESCRD7TION OF THE INVENTION
The embodiments of the present subject matter are described in detail with
reference to the accompanying drawings. However, the present subject matter is not
limited to these embodiments which are only provided to explain more clearly the
present subject matter to the ordinarily skilled in the art of the present disclosure. In
the accompanying drawings, like reference alphabets and numerals are used to
indicate like components. The drawings are not necessarily drawn to the scale, and in
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some instances the drawings have been exaggerated and/or simplified in places for
illustrative purposes only.
The present invention relates to fuel door position sensors and more
particularly to an apparatus, assembly and method for monitoring the closed position
of a fuel door and accordingly indicate the status of the fuel door by an audible/visual
warning indicator provided in a vehicle information display instrument of the
vehicles such as three wheelers, four wheelers, and the like. The following
description is merely exemplary in nature and is not intended to limit the present
disclosure, application, or uses. The present invention will hereinafter be described in
detail, below as applied to a four wheeler. However, the principles of the present
invention are also applicable to other vehicles such as three wheelers, and the like.
Upward, lower, front and rear directions (see the directions indicated by the arrows in
FIG. 1) will be described with respect to directions as seated by the driver in the
vehicle. Further, the present subject matter is explained with reference to a fuel tank
door warning indicator as shown in the vehicle information display instrument of the
four wheelers.
FIG. 1 illustrates a perspective view of the four wheeler 100 in an accordance
with an embodiment of the present subject matter. The four wheeler 100 include an
internal combustion engine to generate a torque required to propel the four wheeler
100. In an embodiment of the present subject matter, the engine may be a gasoline
type engine, diesel powered engine, and the like. The four wheeler 100 is generally
provided with a fuel system 200 that supplies liquid fuel and fuel vapor to the engine
of the four wheeler 100. FIG. 2 and FIG. 3 show the fuel system includes a fuel tank
102 specifically provided to store the liquid fuel for propelling the four wheeler 100.
The liquid fuel is stored in the fuel tank 102 via a fuel inlet 104 structured" as an
integral part of the fuel system 200 as shown in FIG. 4, in an embodiment of the
present subject matter. The fuel inlet 104 is designed as an opening in a side thereof
wherein a substantially cylindrical tube 106 with a threaded end is inserted into the
fuel inlet 104 and thus fixed to the fuel tank 102. The threaded end is screwed by a
fuel filler cap 108 to control the vaporization and theft of the liquid fuel from the fuel
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tank 102. In an embodiment of the present subject matter, the fuel filler cap 108 is
generally protected by a fuel tank door 110 which is pivotally connected to the
extended portion of the cylindrical tube 106 and biased in its opening direction by a
torsion spring (not shown). The fuel tank door 110 is held closed by a locking device
112 that hooks on a protrusion 114 formed on the inner surface of the fuel tank door
110. The locking device 112 is pushed by a wedge shaped extrusion 116 designed
integrally to the fuel tank door 110, in an embodiment of the present subject matter.
The locking device 112 is connected to an opening lever (not shownX provided
beside the driver's seat, by a cable (not shown) such that the locking device 112
unlocks if the driver pulls the opening lever to open the fuel tank door 110. In an
embodiment of the present subject matter, the locking device 112 is designed as a
movable protrusion integral to the inner surface of a lock plate 118 provided with the
fuel tank 102 as shown in FIG. 4. In a preferred embodiment of the present subject
matter, the lock plate 118 is also structured with a plunger body 120 (as shown in
FIG. 5) interior to the locking device 112. The plunger body 120 include a plunger
126 which is pushed by the wedge shaped extrusion 116 once the fuel tank door 110
is completely closed. In an embodiment of the present subject matter, the plunger 126
is continuously pushed during the closed status of the fuel tank door 110. However, if
the fuel tank door 110 is opened (by the driver or the fuel station attendant), plunger
126 will be in its original position of rest which consequently send signals to an
electronic circuit structure via terminals 124 and subsequently to a vehicle
information display apparatus 122 in the four wheeler 100. The signals, thus received,
by the electronic circuit structure will accordingly activate a visible warning indicator
300 in the vehicle information display apparatus 122 to indicate the driver about the
opened status of the fuel tank door 110, in an embodiment of the present subject
matter. In an embodiment of the present subject matter, the plunger body 120 may be
replaced by any other functionally similar mechanical or electronic component. The
material applied in the arrangement should not be a limiting parameter with reference
to the present subject matter.
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During the refilling of the fuel in the four wheeler 100, the driver pulls the
opening lever to open the fuel tank door 110. In this course, the locking device 112
connected to the opening lever also gets pulled resulting in the opening of the fuel
tank door 110. The opening of the fuel tank door 110, as a result, will automatically
actuate signals for displaying the status of the opened fuel tank door 110 as warning
indicator 300 in vehicle information display instrument 122 of the four wheeler 100.
Now, when the fuel tank door 110 is closed after refilling of the liquid fuel, the
locking device 112 is hooked on the protrusion 114 formed on the inner surface of the
fuel tank door 110. On subsequent push of the locking device 112, the fuel tank door
110 further pushes the plunger body 120 (by the wedge shaped extrusion 116) that
consequently push a metallic sleeve 130 (via spring 128 as shown in FIG. 5 and FIG.
6) to generate a continuous signal that further activates an electronic circuit structure
to switch ON the visible warning indicator 300 to glow in the vehicle information
display instrument 122 of the four wheeler 100. In an exemplary embodiment of the
present subject matter, the plunger body 120 has threaded outer portion that can be
screwed and fitted into the lock plate 118. In an embodiment of the present subject
matter, the warning indicator .300 may be an audible buzzer to inform the driver about
the opened status of the fuel tank door. In another embodiment of the present subject
matter, the warning indicator 300 may be in the form of texts displayed on a liquid
crystal display in the vehicle information display instrument of the four wheeler.
The fuel tank door indicator according to the present subject matter
advantageously facilitates an automatic and assured arrangement for sensing,
indicating and thus correcting the status of the fuel tank door. This subject matter
reduces any chance of theft of fuel from the four wheeler to a great extent. Further,
since there are no electronical components involved in the present subject matter,
hence the possible chances of spark and explosion also are foreshortened.
Additionally, the status of the fuel tank door is indicated by a separate warning
indicator 300 (as is evident from FIG. 7) which different from a 'check engine'
warning indicator as present in prior technologies, hence the additional cost of cross
checking the exact malfunction gets diminished. Furthermore, the fuel tank door
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indicator according to the present subject matter beneficially works on any
temperature range since the basic components involved are mechanical in nature.
Therefore, the present subject matter ensures an efficient and reliable arrangement for
indicating the status of fuel tank door of four wheelers. Moreover, since there are not
major complexities involved in terms of the components and their functions, hence
the arrangement is less costly too. In other words, the driver can enjoy a hassle-free
travel without the headache of opened fuel tank door (esp during traffic and on
highways) with the advantages of reliability, less cost, customer's satisfaction, and
the like.
It will be appreciated by those skilled in the art that changes could be made to
the embodiments described above without departing from the broad inventive concept
thereof. The present embodiments are therefore to be considered in all respects as
illustrative and not restrictive, the scope of the invention being indicated by the
appended claims rather than by the foregoing description and all variations,
substitutions and changes which come within the meaning and range of equivalency
of the claims are therefore intended to be embraced therein.

WE CLAIM:
1. A fuel tank door warning indicator 300 for automotive vehicles 100 comprising:
a fuel tank 102 to receive fuel via a fuel inlet 104;
a thread ended cylindrical tube 106 inserted into the fuel inlet 104;
a fuel filler cap 108 screwed on the thread ended cylindrical tube 106;
a fuel tank door 110 pivotally connected to an extended portion of the thread
ended cylindrical tube 106 to cover the fuel filler cap 108 and the fuel tank
102;
a locking device 112 projected as a movable protrusion integral to the inner
surface of a lock plate 118 provided with the fuel tank 102 wherein the
locking device 112 hooks on a protrusion formed on the inner surface of the
fuel tank door 110;
a plunger body 120 structured on interior of the lock plate 118;
the locking device 112 and the plunger body 120 gets pushed by a wedge
shaped extrusion 116 on closing the fuel tank door 110; wherein
the fuel tank door warning indicator 300 is actuated if the plunger body 120
remains non-pushed after closing the fuel tank door 110.
2. The fuel tank door warning indicator 300 as claimed in claim 1, wherein the
wedge shaped extrusion 116 is designed integrally to the fuel tank door 110.
3. The fuel tank door warning indicator 300 as claimed in claim 1, wherein the
locking device 112 is actuated by a cable provided beside the driver's seat.
4. The fuel tank door warning indicator 300 as claimed in claim 1, wherein the
plunger body 120 is continuously pushed during the closed status of the fuel tank
door 110.
5. The fuel tank door warning indicator 300 as claimed in claim 1, wherein the nonpushed
plunger body 120 sends signal to an electronic circuit structure that
subsequently actuates the fuel tank door warning indicator.
6. The fuel tank door warning indicator 300 as claimed in claim 1, wherein the fuel
tank door warning indicator 300 is visible, audible and/or text in nature.
7. The fuel tank door warning indicator 300 as claimed in claim 1, wherein the
plunger body has threaded outer portion to screw into the lock plate.
8. The fuel tank door warning indicator 300 as claimed in claim 1, wherein the fuel
tank door warning indicator 300 is evident on a vehicle information display
instrument 122 of automotive vehicles 100.
9. The fuel tank door warning indicator 300 as claimed in claim 1, wherein the
plunger body 120 may be replaced by any other functionally similar mechanical
or electronic component.
10. The fuel tank door warning indicator 300 as claimed in claim 1 indicates
unclosed or partially closed fuel tank door 110.