DESC:TECHNICAL FIELD
[001] The embodiments herein generally relate to a locking mechanism in vehicles, and more particularly to a locking mechanism for opening and closing a lid of a fuel tank in the vehicles.

BACKGROUND
[002] Vehicle automation also deals with automatic cap assemblies for fuel tanks or automatic fuel lid locking mechanisms. A vehicle body is provided with a fuel filler neck for filling a fuel tank with fuel at outside of the vehicle body and the fuel filler neck is opened and closed by a fuel door openably attached to the vehicle body using a hinge. The fuel door of a vehicle is typically made of steel or plastic and is provided with a locking structure, which can easily open the fuel door in response to a simple manipulation of a button by a driver and can maintain the fuel door in a closed state when a person manually pushes the fuel door after filling the fuel.
[003] In the related art, a locking structure for the fuel door using a push type latch structure has been proposed and used. However, the locking structure using the push type latch structure is problematic in that, even when the fuel door is pushed in a state in which the fuel door is closed and locked, the latch structure may operate and may fail. Fuel filling in the tank of vehicle almost always raises a doubt whether an operator at a petrol bunk has closed the fuel lid properly or not. Improper closing of fuel lid may lead to some safety hazards including fire out or fuel leakage if the fuel cap opens abruptly.
[004] A known art describes an apparatus and circuit for monitoring the closed position of a fuel cap relative to a tank connection pipe. The fuel cap has a ratchet torque limiter for controlling the tightening of the fuel cap to the tank connection pipe. A magnet is connected to the fuel cap and a magnetic switch, such as a reed switch, is connected to the tank connection pipe or proximal thereto. The movement of the magnet relative to the magnetic switch, indicating a locked fuel cap condition, is sensed by an abrupt change in magnetic field strength of the magnet. When releasing members snap over the cams therein, a current pulse is induced in a pickup coil. This current pulse is sensed and a logic level high voltage is produced corresponding to a tightened fuel cap condition. A dashboard lamp is then turned off indicating that the fuel cap is safely and securely tightened.
[005] However the prior art design to ensure the fuel lid locking uses complicated mechanism and serviceability of the mechanism is a major issue.
[006] Hence there exist a need for a simple and effective locking mechanism for locking a lid of a fuel tank in the vehicle and a method for locking a lid of a fuel tank in the vehicle which eliminates the aforementioned drawbacks.

OBJECTS
[007] The principal object of the embodiments of this invention is to provide a simple and effective locking mechanism for locking a lid of a fuel tank in a vehicle.
[008] Another object of the embodiments of this invention is to provide a simple locking mechanism for easy opening and closing of a lid of a fuel tank in a vehicle.
[009] Yet another object of the embodiments of this invention is to provide a simple method of opening and closing a lid of a fuel tank in a vehicle.
[0010] These and other objects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.

BRIEF DESCRIPTION OF DRAWINGS
[0011] The embodiments of the invention are illustrated in the accompanying drawings, through out which like reference letters indicate corresponding parts in the various figures. The embodiments herein will be better understood from the following description with reference to the drawings, in which:
[0012] FIG. 1 illustrates an electro-permanent magnet used in a fuel lid locking mechanism, according to embodiments as disclosed herein;
[0013] FIG. 2 illustrates the booster converter circuit, used in the fuel lid locking mechanism according to embodiments as disclosed herein;
[0014] FIG. 3 illustrates a thyristor bridge circuit used in the fuel lid locking mechanism, according to embodiments as disclosed herein;
[0015] FIG. 4 is a flow diagram illustrating a method for locking a fuel lid when the fuel Lid is in open state, according to embodiments as disclosed herein;
[0016] FIG. 5 is a flow diagram illustrating a method for opening a fuel lid when the fuel Lid is in closed condition, according to embodiments as disclosed herein;
[0017] FIG. 6a and 6b illustrates the mounting of components onto the fuel lid, according to embodiments as disclosed herein;
[0018] FIG. 7 illustrates working of reed switch used for fuel lid operating mechanism, according to embodiments as disclosed herein; and
[0019] FIG. 8 is a flow diagram illustrating a method of opening and closing a lid of a fuel tank in a vehicle, according to embodiments as disclosed herein.

DETAILED DESCRIPTION
[0020] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
[0021] The embodiments herein achieve a simple and effective locking mechanism for locking a lid of a fuel tank in a vehicle. Further, the embodiments herein achieve a simple locking mechanism for easy opening and closing of the lid of the fuel tank in the vehicle. Furthermore, a simple method of opening and closing a lid of a fuel tank in a vehicle. Referring now to the drawings, and more particularly to FIGS. 1 through 8, where similar reference characters denote corresponding features consistently throughout the figures, there are shown embodiments.
[0022] In an embodiment, the fuel lid locking mechanism 100 includes, a fuel tank connection pipe (not shown), a fuel inlet (not shown), a fuel cap 102, housing 104, at least one electro-permanent magnet (not shown) (EPM), a lid 108, a hinge 110, at least one engaging member 112, at least one reed switch 114, at least one permanent magnet 116, at least two ferromagnetic blades 118, a cavity 120, a first toggle switch (not shown), and a second toggle switch (not shown).
[0023] In an embodiment, the fuel lid locking mechanism 100 includes the fuel tank connection pipe (not shown) having the fuel inlet (not shown) with the fuel cap 102 integrated to a body structure of the vehicle. In an embodiment, the fuel is supplied to a fuel tank by the fuel tank connection pipe. The fuel is received through the fuel inlet. The fuel inlet is closed using the fuel cap 102.
[0024] In an embodiment, the fuel lid locking mechanism 100 includes the housing 104. The housing 104 is made of predetermined shape. In an embodiment, the housing 104 is integrated to the fuel tank connection pipe and the fuel inlet. In an embodiment, the fuel cap 102 is contained within the housing 104.
[0025] In an embodiment, the fuel lid locking mechanism 100 includes the lid 108. In an embodiment, the lid 108 is connected to the housing 104 by the hinge 110. In an embodiment, the lid 108 covers the fuel cap 102 when the lid 108 is located in a closed position and in an open position the lid 108 provides access to the fuel cap 102.
[0026] In an embodiment, the fuel lid locking mechanism 100 further includes the at least one engaging member 112. In an embodiment, the at least one engaging member 112 is disposed on the lid 108 at a predetermined position. In an embodiment, the at least one engaging member 112 is a selected from at least one of permanent magnet or a metal strip having magnetic properties.
[0027] FIG. 1 illustrates an electro-permanent magnet used in a fuel lid locking mechanism, according to embodiments as disclosed herein. In an embodiment, the fuel lid locking mechanism 100 includes the at least one electro-permanent magnet (herein after electro-permanent magnet). In an embodiment, the electro-permanent magnet is used to replace the conventional fuel lid closing mechanism which either uses a cable controlled mechanism or a solenoid or an electromagnet. The present day electromagnets require continuous power dissipation to maintain a holding force in contrast to the electro-permanent magnets. In an embodiment, the electro-permanent magnets may be energized and de-energized (i.e. switched on and off) by the application of a momentary electrical pulse. In an embodiment, the fuel lid locking mechanism 100 uses a high instantaneous power but less energy than the conventional systems and reduces an electrical load on the vehicle.
[0028] In an embodiment, the electro-permanent magnet is in the form of a printed circuit board (herein after PCB). In an embodiment, the PCB includes a lower surface which acts as a magnet when an electrical pulse magnetizes it. In an embodiment, the PCB (electro-permanent magnet) includes an exterior surface 106 which engages with the at least one engaging member 112. In an embodiment, the conversion of PCB to a magnetized state is permanent unless a reverse electrical pulse (negative current) of same magnitude is passed in the reverse direction. The magnetized surface attracts the engaging member 112 with a predetermined holding force. In an embodiment, the electro-permanent magnet is enclosed in the housing 104 and the exterior magnetic surface 106 is projected out of it.
[0029] In an embodiment, the engaging member 112 is attached to the fuel lid 108. In an embodiment, the electro-permanent magnet (PCB) includes a first toggle switch (not shown) coupled to the at least one electro-permanent magnet to energized the at least one electro-permanent magnet by a first pulse, and a second toggle switch (not shown) coupled to the at least one electro-permanent magnet to de-energized the at least one electro-permanent magnet by a second pulse. In an embodiment, the first pulse and the second pulse are generated by at least one of current, voltage, and electromagnetic-field energy.
[0030] In an embodiment, the electro-permanent magnet attracts the at least one engaging member 112 and maintains the lid 108 in the closed position when the at least one electro-permanent magnet is energized by the first pulse. In an embodiment, the at least one electro-permanent magnet releases the at least one engaging member 112 and maintains the lid 108 in the open position when the at least one electro-permanent magnet is de-energized by the second pulse.
[0031] In an embodiment, the fuel lid locking mechanism 100 further includes the at least one reed switch 114 (herein after reed switch 114) and the at least one permanent magnet 116 (herein after permanent magnet 116). In an embodiment, the reed switch 114 is affixed on the housing 104 and a permanent magnet is fixed to the fuel lid 108. In an embodiment, the reed switch 114 is configured to indicate a position of the lid 108. The position of the lid 108 includes the open position and the closed position.
[0032] In an embodiment, the reed switch 114 includes the at least two ferromagnetic blades 118 located adjacently in the cavity 120. In an embodiment, the at least two ferromagnetic blades 118 are separated by a predetermined distance. The at least two ferromagnetic blades 118 are held in the predetermined distance by a predetermined spring force. In an embodiment, the at least two ferromagnetic blades 118 are configured to contact each other to form a contact switch when the permanent magnet 116 disposed in the lid 108 is guided towards the reed switch 114.
[0033] In an embodiment, an output (not shown) of the reed switch 114 is fed to a body control module (or ECU), which in turn encodes the output into a CAN signal. This signal available as a known signal in the CAN dbc files of any vehicle platform. The encoding involves mapping of the signal to a particular dataset of a CAN message, which is read through the CAN network of the vehicle and is used to give a “Fuel Lid Open” Alert. This alert can also be visible as a “Tell Tale” on the instrument cluster.
[0034] FIG. 2 illustrates the booster converter circuit used in the fuel lid locking mechanism, according to embodiments as disclosed herein. In an embodiment, the boost converter is a DC to DC converter with an output voltage greater than the source voltage. In an embodiment, the booster convertor is used in the fuel lid locking mechanism 100 to increase the voltage of the momentary electrical pulse.
[0035] FIG. 3 illustrates a thyristor bridge circuit used in the fuel lid locking mechanism, according to embodiments as disclosed herein. In an embodiment, the thyristor is used as a DC switch to control larger DC currents and loads. In an embodiment, the thyristor as a switch it behaves like an electronic latch because once activated it remains in the “ON” state until manually reset.
[0036] FIG. 4 is a flow diagram illustrating a method 400 for locking of the fuel lid when the fuel lid is in open condition, according to embodiments as disclosed herein. In an embodiment, the electro permanent magnet (EPM) facilitates in magnetizing the electro permanent magnet EPM as soon as the fuel filling operation has been completed. In an embodiment, the electro permanent magnet EPM generates a sufficient force to hold the engaging member 112, even if the lid 108 has not been completely closed by a petrol bunk operator.
[0037] In an embodiment, the electro permanent magnet EPM is mounted on the housing 104. Initially, the electro permanent magnet EPM is de-magnetized. In an embodiment, a driver presses the first toggle switch which increases the magnetic flux in the electro permanent magnet EPM and magnetizes its magnetic surface. In an embodiment, when the petrol bunk service operator pushes the fuel lid towards the housing 104 for closure, the electro permanent magnet EPM attracts the engaging member 112 mounted on the fuel lid 108. In an embodiment, the electro permanent magnet EPM generates sufficient pulling force to pull the engaging member 112 even if the lid 108 is not perfectly closed by the operator.
[0038] In an embodiment, the reed switch 114 is mounted on the housing 104. Initially, the reed switch 114 is in open condition. In an embodiment, the permanent magnet 116 needed to close the reed switch 114 is mounted on the fuel lid 108. When the petrol bunk service operator pushes the fuel lid 108 towards the housing 104 for closure, the permanent magnet 116 comes in the vicinity of the reed switch 114 and closes it. In an embodiment, the reed switch output is fed to the ECU, which shares this information over CAN network and trigger a tell-tale for fuel lid closure on an Instrument Cluster.
[0039] An appendage to countering the above problem is to alert the customer that the fuel lid 108 is closed or open. The incorporation of the Reed Switch 114 can provide handy information to the customer about the status of the fuel lid. Collectively, the locking mechanism 100 eliminates the concern in the mind of the driver regarding the status of the fuel lid after fuel filling.
[0040] The various actions in method 400 may be performed in the order presented, in a different order or simultaneously. Further, in some embodiments, some actions listed in FIG. 4 may be omitted.
[0041] FIG. 5 is a flow diagram illustrating a method for opening of the fuel lid when the fuel Lid is in closed condition, according to embodiments as disclosed herein.
[0042] In an embodiment, the exterior magnetic surface 106 of the electro-permanent magnet is demagnetized in the initial state. The first toggle switch is pressed. This causes a positive polarity current to flow, thus magnetizing the electro-permanent magnet. This attracts the engaging member 112, thus keeping the lid 108 closed. When the lid 108 is to be opened for refilling of the fuel, the second toggle switch on the PCB is pressed. This causes a negative polarity current to demagnetize the exterior magnetic surface 106, thus allowing the lid 108 to be opened. After filling the fuel, the fuel lid 108 is closed and the first toggle switch is pressed to magnetize the electro-permanent magnet and keep the fuel lid 108 closed.
[0043] The various actions in method 500 may be performed in the order presented, in a different order or simultaneously. Further, in some embodiments, some actions listed in FIG. 5 may be omitted.
[0044] FIG. 6a and 6b illustrates the mounting of components onto the fuel lid, according to embodiments as disclosed herein. Fig. 6a illustrates the mounted electro-permanent magnet and the engaging member 112, whereas FIG. 6b illustrates the mounted reed switch 114 and the permanent magnet 116. In an embodiment, the at least one engaging member 112 is disposed on the lid 108 at a predetermined position. In an embodiment, the electro-permanent magnet is enclosed in the housing 104 and the exterior magnetic surface 106 is projected out of it. In an embodiment, the reed switch 114 is affixed on the housing 104 and a permanent magnet is fixed to the fuel lid 108.
[0045] FIG. 7 illustrates working of reed switch used for fuel lid operating mechanism, according to embodiments as disclosed herein.
[0046] In an embodiment, the reed switch 114 is configured to indicate a position of the lid 108. The position of the lid 108 includes the open position and the closed position. In an embodiment, the reed switch 114 includes the at least two ferromagnetic blades 118 located adjacently in the cavity 120. In an embodiment, the at least two ferromagnetic blades 118 are separated by a predetermined distance. The at least two ferromagnetic blades 118 are held in the predetermined distance by a predetermined spring force. In an embodiment, the at least two ferromagnetic blades 118 are configured to contact each other to form a contact switch when the permanent magnet 116 disposed in the lid 108 is guided towards the reed switch 114.
[0047] FIG. 8 is a flow diagram illustrating a method 800 of opening and closing a lid of a fuel tank in a vehicle, according to embodiments as disclosed herein. In an embodiment, the method 800 of opening and closing a lid of a fuel tank in a vehicle is disclosed, the vehicle including a fuel tank connection pipe having a fuel inlet with a fuel cap 102, integrated into the vehicle, the method comprising steps of, integrating a housing 104 to the fuel tank connection pipe and the fuel inlet (step 802). Further, the method includes, coupling a lid 108 to the housing 104 by a hinge 110 (step 804), wherein in a closed position the lid 108 covers the fuel cap 102 and in an open position the lid 108 provides access to the fuel cap 102. Furthermore, the method includes mounting at least one engaging member 112 on the lid 108 at a predetermined location (step 806). In addition the method includes, providing at least one electro-permanent magnet in the housing 104 (step 808). In an embodiment, the at least one electro-permanent magnet includes an exterior surface 106 configured to contact the at least one engaging member 112 when the lid 108 is in the closed position. In an embodiment, the at least one electro-permanent magnet attracts the at least one engaging member 112 and maintains the lid 108 in the closed position when the at least one electro-permanent magnet is energized by a first pulse. In an embodiment, the at least one electro-permanent magnet releases the at least one engaging member 112 and maintains the lid 108 in the open position when the at least one electro-permanent magnet is de-energized by the second pulse.
[0048] The embodiments disclosed herein can be implemented through at least one software program running on at least one hardware device and performing network management functions to control the network elements. The network elements shown in Fig. 1 through 8 include blocks which can be at least one of a hardware device, or a combination of hardware device and software module.
[0049] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

Referral numerals:
Locking mechanism 100
Fuel cap 102
housing 104
Electro-permanent magnet exterior surface 106
lid 108
hinge 110
Engaging member 112
Reed switch 114
Permanent magnet 116
Ferromagnetic blade 118
cavity 120
,CLAIMS:STATEMENT OF CLAIMS
We claim,
1. A fuel lid locking mechanism 100 for a vehicle, the vehicle including a fuel tank connection pipe having a fuel inlet with a fuel cap 102, integrated into the vehicle, the locking mechanism comprising:
a housing 104 integrated to the fuel tank connection pipe and the fuel inlet;
a lid 108 coupled to the housing 104 by a hinge 110, wherein in a closed position the lid 108 covers the fuel cap 102 and in an open position the lid 108 provides access to the fuel cap 102;
at least one engaging member 112 mounted on the lid 108 at a predetermined location; and
at least one electro-permanent magnet disposed in the housing 104;
wherein
the at least one electro-permanent magnet includes an exterior surface 106 configured to contact the at least one engaging member 112 when the lid 108 is in the closed position;
the at least one electro-permanent magnet attracts the at least one engaging member 112 and maintains the lid 108 in the closed position when the at least one electro-permanent magnet is energized by a first pulse,
and
the at least one electro-permanent magnet releases the at least one engaging member 112 and maintains the lid 108 in the open position when the at least one electro-permanent magnet is de-energized by a second pulse.
2. The fuel lid locking mechanism 100 as claimed in claim 1, wherein the fuel lid locking mechanism 100 further includes:
at least one reed switch 114 disposed in the housing 104; and
at least one permanent magnet 116 disposed in the lid 108;
wherein
the at least one reed switch 114 is configured to indicate a position of the lid 108;
the position of the lid 108 includes the open position and the closed position.
3. The fuel lid locking mechanism 100 as claimed in claim 2, wherein the at least one reed switch 114 includes:
at least two ferromagnetic blades 118 located adjacently in a cavity 120;
wherein
the at least two ferromagnetic blades 118 are separated by a predetermined distance;
the at least two ferromagnetic blades 118 are configured to contact each other to form a contact switch when the permanent magnet 116 disposed in the lid 108 is guided towards the at least one reed switch 114.
4. The fuel lid locking mechanism 100 as claimed in claim 1, wherein the first pulse and the second pulse are generated by at least one of current, voltage, and electromagnetic-field energy.
5. The fuel lid locking mechanism 100 as claimed in claim 1, wherein the locking mechanism 100 further includes:
a first toggle switch coupled to the at least one electro-permanent magnet to energized the at least one electro-permanent magnet by the first pulse; and
a second toggle switch coupled to the at least one electro-permanent magnet to de-energized the at least one electro-permanent magnet by the second pulse.
6. A method 800 of opening and closing a lid 108 of a fuel tank in a vehicle, the vehicle including a fuel tank connection pipe having a fuel inlet with a fuel cap, integrated into the vehicle, the method 800 comprising steps of:
integrating a housing 104 to the fuel tank connection pipe and the fuel inlet;
coupling a lid 108 to the housing 104 by a hinge 110, wherein in a closed position the lid 108 covers the fuel cap 102 and in an open position the lid 108 provides access to the fuel cap 102;
mounting at least one engaging member 112 on the lid 108 at a predetermined location; and
providing at least one electro-permanent magnet in the housing 104;
wherein
the at least one electro-permanent magnet includes an exterior surface 106 configured to contact the at least one engaging member 112 when the lid 108 is in the closed position;
the at least one electro-permanent magnet attracts the at least one engaging member 112 and maintains the lid 108 in the closed position when the at least one electro-permanent magnet is energized by a first pulse,
and
the at least one electro-permanent magnet releases the at least one engaging member 112 and maintains the lid 108 in the open position when the at least one electro-permanent magnet is de-energized by the second pulse.
7. The method as claimed in claim 6, wherein the locking mechanism further including:
a reed switch 114 disposed in the housing 104; and
a permanent magnet 116 disposed in the lid 108;
wherein
the reed switch 114 is configured to indicate a position of the lid 108;
the position of the lid 108 includes the open position and the closed position.
8. The method as claimed in claim 7, wherein the reed switch 114 includes:
at least two ferromagnetic blades 118 located adjacently in a cavity 120;
wherein
the at least two ferromagnetic blades 118 are separated by a predetermined distance;
the at least two ferromagnetic blades 118 are configured to contact each other to form a contact switch when the permanent magnet 116 disposed in the lid 108 is guided towards the reed switch 114.
9. The method as claimed in claim 6, wherein the first pulse and the second pulse are generated by at least one of current, voltage, and electromagnetic-field energy.
10. The method as claimed in claim 6, wherein the locking mechanism further including:
at least one first toggle switch coupled to the at least one electro-permanent magnet to energized the at least one electro-permanent magnet by the first pulse; and
at least one second toggle switch coupled to the at least one electro-permanent magnet to de-energized the at least one electro-permanent magnet by the second pulse.