FIELD OF PRESENT INVENTION
The present invention relates to a locking device. More particularly, the present invention relates
to a locking device for a fuel tank of a vehicle having a shutter plate with an auto-return
mechanism.
BACKGROUND OF INVENTION
It is known that fuel tank caps are provided on fuel tanks for preventing fuel leakage and thefts.
These fuel tank caps are either hinge type or bayonet type. Further, in hinge type caps, the shutter
plate is provided on top of caps to protect the key insertion hole or key-hole from dust and water.
During filling of fuel in the vehicle the shutter plate is first opened by the rider to uncover the
key-hole. The lock is operated with the help of key. Such protecting shutter plates are usually
hinged type. This type of shutter plate limits the amount by which fuel tank cap can be opened
during filling of fuel in the vehicle or fuelling in the vehicle thereby making fuelling difficult at
gas station. Further, when the fuel tank cap is operated with the shutter plate in open condition,
either key or rider’s hand touches with the shutter plate. This makes the fuel tank cap usage
difficult.
On the other hand, in case of bayonet type caps, the whole cap has to be taken out for fuelling
which consequently makes handling difficult.
In the existing locking caps, where the shutter plate is being provided to cover the key-hole, the
shutter plate has to be open and close manually. There are instances when the operator may
forget to close the shutter plate after using the fuel tank cap. This consequently leads to the entry
of water and dust in the locking area and reducing the life of the lock.
OBJECTIVES OF THE PRESENT INVENTION
The main objective of the present invention is to overcome at least one of the above mentioned
problems.
Another objective of the present invention is to provide a locking device for a fuel tank of a
vehicle.
Still another objective of the present invention is to provide a locking device for a fuel tank of a
vehicle having a shutter plate with an auto-return mechanism.
3
BRIEF DESCRIPTION OF THE DRAWINGS
Further aspects and advantages of the present invention will be readily understood from the
following detailed description with reference to the accompanying figures.
The figures together with a detailed description below, are incorporated in and form part of
the specification, and serve to further illustrate the aspects and explain various principles
and advantages, in accordance with the present invention wherein:
Figure 1: shows a locking device of conventional technology.
Figure 2: is a perspective view of the locking device according to an aspect of the present
invention.
Figure 3: is a perspective view of the locking device comprising mounting base and shutter plate
according to an aspect of the present invention.
Figures 4-5: are perspective views of the mounting base and shutter plate according to an aspect
of the present invention respectively.
Figure 6: shows a bottom view of the shutter plate according to an aspect of the present invention
Figures 7-14: show views of locking device during working of the same according to an aspect
of the present invention.
Figure 15: shows the side view of the locking device comprising locking means according to an
aspect of the present invention.
DESCRIPTION OF THE PRESENT INVENTION
While the invention is susceptible to various modifications and alternative forms, specific
embodiment thereof has been shown by way of example in the figures and will be
described in detail 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 as defined by the appended claims.
Before describing in detail aspects it may be observed that the novelty and inventive
step that are in accordance with the present invention resides in locking device for a fuel tank
of a vehicle. It is to be noted that a person skilled in the art can be motivated from the
4
present invention and modify the various constructions of assembly. However, such
modification should be construed within the scope and spirit of the invention.
Accordingly, the drawings are showing only those specific details that are pertinent to
understanding the aspects of the present invention so as not to obscure the disclosure with
details that will be readily apparent to those of ordinary skill in the art having benefit of the
description herein.
The terms “comprises”, “comprising”, or any other variations thereof, are intended to cover
a non-exclusive inclusion, such that a setup, locking device that comprises a list of
components does not include only those components but may include other components not
expressly listed or inherent to such setup or locking device. In other words, one or more
elements in a system or locking device proceeded by “comprises… a” does not, without more
constraints, preclude the existence of other elements or additional elements in the locking
device. The following paragraphs explain present invention wherein a locking device for a fuel
tank of a vehicle (as shown in figure 2). The invention in respect of the same may be deduced
accordingly.
Accordingly the present invention relates to a locking device for a fuel tank of vehicle with an
auto-return shutter plate comprising a mounting base assembly (15) and a mounting plate (8),
the mounting base assembly is provided with plurality of slots for assembling of the mounting
plate (8) coaxially with the mounting base (15), the said mounting plate (8) is being provided
with plurality of grooves ,whereby the first groove (9) is provided to accommodate a rotor (4),
and at least three pair of grooves(8a,8b,8c,8d,8e,8f) provided around the rotor (4) assembly,
wherein one pair of groove (8e,8f) accommodates a main resilience means (11,12), the other
pairs of grooves (8a,8b,8c,8d) accommodates resiliently energized locking means (6a,6b,7a,7b)
in each groove; the rotor (4) provided with at least one pair of diagonally opposite protruded
portion on the periphery of the rotor (4) that remains in contact with diagonally placed locking
means (6a,6b,7a,7b); a shutter plate (1) being slidably mounted on the cover plate (9), the said
shutter plate (1) having U shape, the shutter plate (1) provided with plurality of longitudinal
grooves on the bottom surface of the shutter plate (1) to accommodate the main resilience means
(11, 12).
5
A first aspect of the present invention wherein the rotor (4) comprises a key slot (5) disposed in
the rotor (4).
A second aspect of the present invention wherein the mounting plate (8) is provided with at least
two pairs of longitudinal grooves (8a, 8b, 8c, 8d) on the periphery of the rotor (4) to resiliently
accommodate the pair of primary locking means (6a, 6b) and pair of secondary locking means
(7a, 7b), wherein the primary locking means are disposed diagonally opposite to each other in
grooves (8a, 8c) and the secondary locking means (7a, 7b) disposed in grooves (8b,8d).
Also another aspect of the present invention wherein the protruded portion provided on the rotor
(4) remains in contact with tip of either primary locking means (6a, 6b) or secondary locking
means (7a,7b) at LOCK position and UNLOCK position respectively.
Also another aspect of the present invention wherein the locking means (6a, 6b, 7a, 7b) are
accommodated with auxiliary resilient means.
Also another aspect of the present invention wherein the main resilience means (11,12) disposed
in the pair of grooves (8e, 8f) provided in the mounting plate (8) tends to push the shutter plate
(1) to close position.
Yet another aspect of the present invention wherein the shutter plate (1) is slidably open by user
either manually or by key
Yet another aspect of the present invention wherein the shutter plate (1) is capable of being
engage and disengage with either primary locking means (6a,6b) or the secondary locking means
(7a, 7b) at LOCK or UNLOCK position respectively from the slots (1a,1b,1c,1d) provided on the
both longitudinal side (2,3) of the shutter plate (1) .
In one another aspect of the present invention wherein the longitudinal grooves (14, 15) on the
bottom surface of shutter plate are extending between lateral side (10) of shutter plate (1) to the
rotor.
6
In another aspect of the present invention wherein the longitudinal grooves on the bottom surface
of shutter plate are extending from lateral side (10) and longitudinal sides (2, 3) up to
predetermined distance
In yet another aspect of the present invention wherein the longitudinal grooves (1a, 1b, 1c, 1d)
on the bottom surface of shutter plate are accommodating and engaging locking means (6a, 6b,
7a,7b) in such a manner that rotation of the rotor disengages the locking means from the shutter
plate.
Yet another aspect of the present invention wherein the auto return of the shutter plate (1)
mechanism covers the key slot 5 , upon rotating the key in the key slot (5) from UNLOCK to
LOCK position and withdrawing the same, the auto return of shutter plate mechanism involves
the de-energizing of main resilience means (11,12) disposed in the grooves (8e, 8f) of the
mounting plate (8) which is in connection with the grooves (13,14) provided on the bottom
surface of the shutter plate (1), this de-energizing of main resilience means (11,12) moves the
shutter plate (1) to closing position and closes the key slot 5 in response to withdrawing the key
from the key slot 5.
Accordingly the present invention provides a locking device for a fuel tank of vehicle comprising
a shutter plate (1) mounted on mounting sub-assembly and a base for mounting of mounting subassembly
according to an embodiment of the present invention. The mounting sub-assembly
comprises a mounting base (15), a cover plate, plurality of resilience means such as main
resilience means (11, 12) which tend to energize in a direction to move the shutter plate (1) in
close position and auxiliary resilience means which tend to energize in a direction to move
locking means (6a, 6b, 7a, 7b) in locking position, locking means i.e. primary locking means (6a,
6b) and secondary locking means (7a, 7b) and a rotor (4) as shown in figure 4. The shutter is
slidably mounted on the cover plate. The mounting base (15) is provided with plurality of holes
for fixing of the mounting plate (8) on the base. The mounting plate (8) consist plurality of
grooves of predetermined length to accommodate the main resilience means (11,12) and locking
means (6a, 6b, 7a, 7b) along with auxiliary resilience means therein. The resilience means are
being provided to support the reciprocating movements of locking means (6a, 6b, 7a, 7b) and
shutter plate (1). The primary locking means (6a, 6b) and secondary locking means (7a, 7b) are
7
preferably two in numbers. The locking means (6a, 6b, 7a, 7b) have a protruded portion at its
rear side while a round edge on front side. A groove (9) is provided centrally in mounting base
(8) to accommodate the rotor (4) at predetermined location in such a way that primary locking
means (6a, 6b) and secondary locking means (7a, 7b) are mounted on periphery of the rotor (4).
The rotor (4) comprises a key slot (5) centrally disposed in the rotor (4). The front sides of
primary locking means (6a, 6b) and secondary locking means (7a, 7b) having round edges which
faces rotor (4). The locking means (6a, 6b, 7a, 7b) are L shaped. The L shaped locking means
have a vertical and a horizontal portion, the said vertical portion is extended perpendicular to the
surface of the mounting plate (8) and engagable with the shutter plate, the said horizontal portion
is extended towards the periphery of the rotor (4).Preferably, both primary locking means (6a,
6b) are placed diagonally in longitudinal grooves (8a, 8c) provided in the mounting plate (8) i.e.
one primary locking means is placed at one side of the rotor (4) while the other primary locking
means is placed on another side of the rotor at the diagonal end. In similar way both the
secondary locking means (7a, 7b) are also placed diagonally in the longitudinal grooves (8b, 8d).
The rotor (4) has one or more extruded portion at predetermined location having round edges.
Preferably, two protruded portions are being provided which are located the end of diameter of
the rotor (4).
Referring to figure 5 and figure 6, the shutter plate (1) is provided with one or more extended
portions such as legs. The legs are sufficiently apart from each other so as to allow insertion of
key into the key slot (5) of rotor (4). Plurality of grooves are being provided on bottom surface
and longitudinal surface (2,3) of the shutter plate (1) at predetermined locations. A pressing area
is being provided on top surface of the shutter plate (1) at the adjoining portion of the legs. The
shutter plate (1) is movably mounted on the mounting plate (8). The slots (14, 15) provided at
lateral side (10) of the shutter plate (1) accommodate the resilience means as shown in figure 6.
The shutter plate (1) is provided with three pair of longitudinal grooves (1a, 1b, 1c, 1d , 16, 17)
wherein two pair of longitudinal grooves (1a, 1b, 1c, 1d) are provided on the bottom surface
shutter and extending from longitudinal sides (2, 3) and one pair (16, 17) are provided on the
bottom surface of the shutter plate which are extending from lateral side (10) and longitudinal
side (2, 3) up to a predetermined distance and one pair of slot (14, 15) provided on the lateral
side (10) of the shutter plate (1) to accommodate the main spring as shown in the figure 6,
wherein the figure 6 shows the bottom view of the shutter plate (1). The locking means (6a, 6b,
8
7a, 7b) are engage able in the longitudinal grooves (1a, 1b, 1c, 1d) to lock the position of the
shutter plate (1).
The different stages of the locking device during the operation are described as follows:
Stage 1: Locking device is locked and shutter plate (1) is in closed position.
Referring to figure 2(a), the shutter plate (1) is shown in closed position in figure 2a. In this
situation, the closed shutter plate (1) has covered the key slot (5) completely.
Stage 2: Locking device is locked and shutter plate (1) is in open position.
Referring to figures 2(a) and 2(b) via figure 7, the shutter plate (1) is shown in closed position in
figure 2a while the figure 2(b) shows the shutter plate (1) in open position. It can be seen from
figure 2(b) that when the shutter plate (1) is in open position, it uncovers the key slot (5).
The shutter plate (1) is opened by sliding the pressing area by any external means such finger or
key. Once the shutter plate (1) is pressed backwardly, it is locked with the help of primary
locking means (6a, 6b). As shown in figures 4 and 6, the extruded portions of the rotor (4) have
pressed the secondary locking means (7a, 7b) and primary locking means (6a, 6b) are in released
position. As the shutter plate (1) slides backwardly, the longitudinal grooves (1a, 1d) are
provided in shutter plate (1) which , engages with primary locking means (6a, 6b) as shown in
figures ( 7) and ( 12). In such way the primary locking means (6a, 6b) lock this position of the
shutter plate (1). Now, as the shutter plate (1) is pushed away from rotor, therefore, the key slot
(5) is uncovered.
Stage 3: Locking device is unlocked and shutter plate (1) is engaged with secondary locking
means (7a, 7b).
Referring to figure 8, as the key is being inserted in key slot (5) and rotated in a predetermined
direction to unlock the locking device, the extruded portions of the rotor (4) shift from secondary
locking means (7a, 7b) to primary locking means (6a, 6b) i.e. the rotor pushes the primary
locking mean (6a, 6b) against the auxiliary resilience means and releases the secondary locking
means (7a, 7b) to move due to the auxiliary resilience means. This shifting causes the primary
locking means (6a, 6b) to move away from rotor (4) so as to unlock the shutter plate (1) from
9
locking engagement between shutter plate (1) and primary locking means (6a, 6b) as shown in
figures ( 8). As the shutter plate (1) is unlocked from primary locking means (6a, 6b), due to the
restoring force of main resilience means (11, 12) the shutter plate (1) will slightly move toward
rotor (4). Meanwhile, as the secondary locking means (6a, 6b) are in released position now,
therefore, the secondary locking means (7a, 7b) will tend to move toward rotor (4) due to the
restoring resilience force of auxiliary resilience means. In this way, the protruded portion of the
secondary locking means (7a, 7b) will engages with the longitudinal grooves (1b, 1d) provided
on the longitudinal sides (2, 3) of the shutter plate as shown in the figures ( 8) and ( 11) (figure
13 shows the locking at other end of the shutter plate (1)).
Stage 4: Locking device is locked and shutter plate (1) is free from its engagement with the
secondary locking means (7a, 7b).
Referring to figure 9, when the key is being rotated in a predetermined direction to lock the
locking device, the extruded portions of the rotor (4) again shift from primary locking means (6a,
6b) to secondary locking means (7a, 7b). This shifting causes the secondary locking means (7a,
7b) to move away from rotor (4) against the resilience force so as to unlock the shutter plate (1)
from locking engagement between shutter plate (1) and secondary locking means (7a, 7b) as
shown in figures ( 9). As the shutter plate (1) is unlocked from the secondary locking means (7a,
7b), due to the restoring force of main resilience means (11, 12) the shutter plate (1) will tend to
move toward rotor (4). In this situation, as the shutter plate (1) is not locked with any locking
means (6a, 6b, 7a, 7b), therefore the adjoining portion of legs of shutter plate (1) lies against the
key itself.
Stage 5: Locking device is locked and shutter plate (1) closes automatically.
Now, as described in previous stage, the shutter plate (1) lies against the key. Therefore, as the
key is being taken out from the key-slot (5), the shutter plate (1) will automatically cover the
key- slot (1) due to restoring force of main resilience means (11, 12) as shown in figures ( 10)
and ( 14) (figure 14 shows the locking at other end of the shutter plate (1)).
Referring to figure 15, the protruded portions of the locking means are provided with varying
height according to an aspect of the present invention. Both the locking means (6a, 7b) placed
toward the lateral side (10) of the shutter plate (1) are having comparatively shorter height
10
protruded portion than the other two locking means (6b, 7a). This variation in height is being
provided to facilitate the proper locking of the shutter plate (1).The size of the vertical portion of
the locking means (6a, 6b, 6c, 6d) are different such that it permits atleast one diagonal locking
of the shutter. The shutter plate (1) also has variation in height in the longitudinal grooves (8a,
8b, 8c, 8d) provided therein so as to accommodate the locking means of respective heights.
ADVANTAGES OF THE PRESENT INVENTION
The advantage of the present invention is to provide a locking device for fuel tank of a vehicle.
One more advantage of the present invention is to provide a locking device for fuel tank of a
vehicle with a shutter plate (1) to cover the key slot (5).
Another advantage of the present invention is to provide a locking device for fuel tank of a
vehicle with a shutter plate (1) having auto-return mechanism.
The inventors have developed the invention, so that advantage can be achieved in an
economical, practical, and facile manner. While preferred aspects and example
configurations have been shown and described, it is to be understood that various further
modifications and additional configurations will be apparent to those skilled in the art. It is
intended that the specific embodiments and configurations herein disclosed are illustrative of
the preferred nature of the invention, and should not be interpreted as limitations on the
scope of the invention.

We claim:
1. A locking device for a fuel tank of vehicle with an auto-return shutter plate comprising:
a mounting base assembly (15) and a mounting plate (8), the mounting base
assembly is provided with plurality of slots for assembling of the mounting plate
(8) coaxially with the mounting base (15), the said mounting plate (8) is being
provided with plurality of grooves ,whereby the first groove (9) is provided to
accommodate a rotor (4), and at least three pair of grooves(8a,8b,8c,8d,8e,8f)
provided around the rotor (4) assembly, wherein one pair of groove (8e,8f)
accommodates a main resilience means (11,12), the other pairs of grooves
(8a,8b,8c,8d) accommodates resiliently energized locking means (6a,6b,7a,7b) in
each groove;
the rotor (4) provided with at least one pair of diagonally opposite protruded
portion on the periphery of the rotor (4) that remains in contact with diagonally
placed locking means (6a,6b,7a,7b);
a shutter plate (1) being slidably fixed on the cover plate (9), the said shutter plate
(1) having U shape, the shutter plate (1) provided with plurality of longitudinal
grooves on the bottom surface of the shutter plate (1) to accommodate the main
resilience means (11, 12).
2. The locking device as claimed in claim 1, wherein the rotor (4) comprises a key slot (5)
disposed in the rotor (4).
3. The locking device as claimed in claim 1, wherein the mounting plate (8) is provided
with at least two pairs of longitudinal grooves (8a, 8b, 8c, 8d) on the periphery of the
rotor (4) to resiliently accommodate the pair of primary locking means (6a, 6b) and pair
of secondary locking means (7a, 7b), wherein the primary locking means are disposed
diagonally opposite to each other in grooves (8a, 8c) and the secondary locking means
(7a, 7b) disposed in grooves (8b,8d).
12
4. The locking device as claimed in claim 1, wherein the protruded portion provided on the
rotor (4) remains in contact with tip of either primary locking means (6a, 6b) or
secondary locking means (7a,7b) at LOCK position and UNLCOK position respectively.
5. The locking device as claimed in claim 1, wherein the locking means (6a, 6b, 7a, 7b) are
accommodated with auxiliary resilient means.
6. The locking device as claimed in claim 1, wherein the main resilience means (11,12)
disposed in the pair of grooves (8e, 8f) provided in the mounting plate (8) tends to push
the shutter plate (1) to close position.
7. The locking device as claimed in claim 1 , wherein the shutter plate (1) is slidably open
by user either manually or by key
8. The locking means as claimed in claim 1, wherein the shutter plate (1) is capable of being
engage and disengage with either primary locking means (6a,6b) or the secondary
locking means (7a, 7b) at LOCK or UNLOCK position respectively from the slots
(1a,1b,1c,1d) provided on the both longitudinal side (2,3) of the shutter plate (1) .
9. The locking means as claimed in claim 1, wherein the longitudinal grooves (14, 15) on
the bottom surface of shutter plate are extending between lateral side (10) of shutter plate
(1) to the rotor.
10. The locking means as claimed in claim 9, wherein the longitudinal grooves on the bottom
surface of shutter plate are extending from lateral side (10) and longitudinal sides (2, 3)
up to predetermined distance
11. The locking means as claimed in claim 1 and 9, wherein the longitudinal grooves (1a, 1b,
1c, 1d) on the bottom surface of shutter plate are accommodating and engaging locking
means (6a, 6b, 7a,7b) in such a manner that rotation of the rotor disengages the locking
means from the shutter plate.
13
12. The locking device as claimed in claim 1, wherein the auto return of the shutter plate (1)
mechanism covers the key slot 5, upon rotating the key in the key slot (5) from
UNLOCK to LOCK position and withdrawing the same, the auto return of shutter plate
mechanism involves the de-energizing of main resilience means (11,12) disposed in the
grooves (8e, 8f) of the mounting plate (8) which is in connection with the grooves (13,14)
provided on the bottom surface of the shutter plate (1), this de-energizing of main
resilience means (11,12) moves the shutter plate (1) to closing position and closes the key
slot 5 in response to withdrawing the key from the key slot 5.