FIELD OF INVENTION
[01] The present disclosure generally relates to sensors used to detect fuel level. More
particularly, the present disclosure relates to an apparatus and a method for determining a level of fuel in a reservoir such as a fuel tank.
BACKGROUND
[02] All automobiles such as trucks, cars, buses and so on currently utilize internal
combustion engines. Generally, the internal combustion engines run on fuel such as petrol, diesel and so on. Typically, the fuel is stored in a fuel tank/reservoir.
[03] Conventionally, the automobile comprises a fuel monitoring system for monitoring/
measuring a level of the fuel in the fuel tank. The fuel monitoring system comprises a fuel sensing unit (such as fuel sensors) and a fuel gauge. Generally, the fuel sensing unit is provided in the fuel tank/reservoir and the fuel gauge is provided in a dashboard of the automobile. The fuel sensing unit is configured for determining the level of the fuel in the fuel tank. The fuel gauge is configured for providing a reading of the level of the fuel in the fuel tank.
[04] The fuel sensing unit comprises a float object and a float arm. The float object is placed
on surface of the fuel in the fuel tank. The float object is coupled to the float arm via a pin joint. The float arm is provided in a shape of a bar or rod. The float arm is also known as a lever arm. The float arm moves in relation to the float object floating on surface of the fuel in the reservoir.
[05] In one example, when the reservoir is filled with the fuel, the float object floats on top
surface of the fuel and the float arm moves up from the base of the reservoir. In another example, when the reservoir is empty i.e., no fuel available in the reservoir, the float object rests on base of the reservoir and the float arm moves down toward the base of the reservoir.

[06] The float arm is further communicatively coupled to the fuel sensing unit via a resistor
for detecting the movement of the float arm in the reservoir. The resistor is electrically connected to a battery for receiving electric charge as input. The resistor is configured for transferring a heat/current in response to the movement of the float arm, through the resistor to the fuel gauge.
[07] In one example, when the reservoir is full with the fuel, the resistor detects the movement of the float arm and generates small resistance with respect to position of the float arm in the fuel sensing unit and provides current at low voltage which passes through the fuel sensing unit to the fuel gauge. It should be understood that the resistance is directly proportional to the current i.e., when the resistance increases, the current increases and when the resistance decreases, the current decreases as well.
[08] Further, the fuel gauge comprises a heating coil and a bimetallic strip. The heating coil is coupled to the resistor for receiving the heat generated in response to the movement of the float arm. Further, the heating coil and the bimetallic strip are coupled in such a way to transfer a heat through the heating coil to the bimetallic strip. The bimetallic strip is generally made up of two metals combination such as brass and steel or copper and steel, with different expansion coefficients. The metals strips are joined together throughout their length by riveting, brazing or welding. The bimetallic strip expands and contracts in response to the temperature change received by the heating coil.
[09] In one example, as the resistance decreases (fuel level ups), less current passes through the heating coil and the bimetallic strip cools down (contract). In other example, as the resistance increases (fuel level drops), large current passes through the heating coil and the bimetallic strip heats (expand).
[010] Further, the bimetallic strip is coupled to the gauge for providing mechanical displacement in response to the expansion and contraction of the bimetallic strip and the gauge indicates the reading of the fuel level in the reservoir.

[Oil] In one example, as the bimetallic strip cools, the strip straightens out and pulls an indicator of the gauge from empty level of fuel reading to full level of fuel reading. In another example, as the bimetallic strip heats, the strip bends in and pushes the indicator of the gauge from full level of fuel reading to empty level of fuel reading.
[012] Typically, the components of the conventional fuel monitoring systems wear over time due to mechanical contacts, have limited life cycle and produces measurement errors, etc. Further, the components may not be able to survive long term exposure to fuel used in the automobiles. For example, exposure to methanol, ethanol and other additive breaks down the linking adhesives and eventually the float arm and the resistive components opens up causing operational failure of the fuel monitoring systems.
[013] Further, in another conventional technique, the fuel monitoring systems comprise a first microprocessor which reads the resistor network in the fuel tank and communicates the readings to a second microprocessor which in turn displays the fuel level through the fuel gauge. However the above described techniques are complex to use.
SUMMARY
[014] Before the present and methods, the embodiments are described, it is to be understood that this description is not limited to the particular systems, and methodologies described below, as there can be multiple possible embodiments of the present description and which are not expressly illustrated in the present disclosures. It is also to be understood that the terminology used in the description is for the purpose of describing the particular versions or embodiments only, and is not intended to limit the scope of the present description.
[015] The present description provides an apparatus and a method for determining a level of fuel in a resorvoir.
[016] It is the primary object of the present disclosure is to provide an apparatus and a method for determining a level of fuel in a reservoir.

[017] It is yet another object of the disclosure is to provide an apparatus comprising a magnet holder wherein the float object is coupled to the magnet holder through the float arm. The magnet holder comprising a magnet rotatably fixed in magnet holder. Further, the apparatus comprises a hall sensor communicatively coupled to the magnet holder to provide an output voltage that is proportional to the applied magnetic field intensity.
[018] It is yet another object of the disclosure is to provide an apparatus which provides linear readings of the level of fuel inside the fuel tank.
[019] It is yet another object of the present disclosure is to provide an apparatus which eliminates the operational failures due to mechanical contacts and long term exposure to the fuel.
[020] In one embodiment of the present disclosure, the apparatus for determining a level of fuel in a reservoir is disclosed. The apparatus comprises a float object and a float arm. Further, the apparatus comprises a magnet holder. One end of the float arm is coupled to the float object and other end of the float arm is coupled to the magnet holder. The magnet holder moves with respect to movement of the float object in the reservoir. The magnet holder comprises a magnet wherein the magnet is provided as ratable form and induces a magnetic field. The apparatus comprises a hall sensor in proximity of the magnet holder. The hall sensor and the magnet are communicatively coupled with respect to movement of the magnet holder. The hall sensor is configured to provide an output voltage proportional to the induced magnetic field intensity and drives the fuel gauge to determine the level of fuel in the reservoir.
[021] The method of the present disclosure comprises generating a variable magnetic field in accordance with the variations in the level of the fuel in the reservoir, detecting the variations in the variable magnetic field representative of different levels of the fuel in the reservoir and providing an output voltage proportional to the variations in the magnetic field intensity to indicate the fuel level inside the reservoir.

BRIEF DESCRIPTION OF FIGURES
[022] The foregoing summary, as well as the following detailed description of preferred embodiments, are better understood when read in conjunction with the appended drawings. For the purpose of illustration exemplary constructions of the description are shown in the drawings; however, the description is not limited to the specific methods and system disclosed.
[023] Figure 1 illustrates a reservoir, in accordance with an embodiment of the present disclosure.
[024] Figure 2 illustrates an apparatus for determining a level of fuel in the reservoir, in accordance with an embodiment of the present disclosure.
[025] Figure 3 illustrates a perspective view of the apparatus for determining a level of fuel in the reservoir, in accordance with an embodiment of the present disclosure.
[026] Figure 4 illustrates a side view of the apparatus, in accordance with an embodiment of the present disclosure.
[027] Figure 5 illustrates an exemplary implementation of the apparatus used to a determining a level of fuel in the reservoir, in accordance with an embodiment of the present disclosure.
DETAILED DESCRD?TION
[028] Some embodiments of this disclosure, illustrating its core functional features, will now be described below:
[029] The disclosed embodiments are merely exemplary of the description, which may be embodied in various forms.

[030] Present description generally relates to sensors used to determine a level of fuel in the reservoir.
[031] The words reservoir and fuel tank, mean the same and are used interchangeably in the description.
[032] Referring to Figure 1, a reservoir 100 used to store fuel is shown. The reservoir 100 may be made up aluminum or high-density polyethylene HDPE capable of withstanding pressure caused by the fuel such as petrol and diesel stored in the reservoir 100. The reservoir 100 may be i provided in various shapes and sizes depending upon an automobile in which the reservoir 100 is used. The reservoir 100 comprises an opening 105 at the top surface of the reservoir 100 to receive fuel 110 into the reservoir 100.
[033] Referring to Figure 2, the reservoir 100 comprises an apparatus 200. The apparatus 200 is provided at one corner e.g., at the top surface of the reservoir 100. The apparatus 200 is made up of plastic or stainless steel material. The apparatus 200 is provided in a shape of square, rectangular or any other shape. Further, the apparatus 200 comprises a float object 204 and a float arm 206. The float object 204 is made of a noncorrosive material such as plastic, stainless steel and so on. The float arm 206 is also made up of noncorrosive material. As can be seen, one i end of the float arm 206 is coupled to the float object 204 via a pin joint (not shown) and other end of the float arm 206 is coupled to the apparatus 200.
[034] Now referring to Figure 3, 4 and 5, the apparatus 200 is shown in accordance with an embodiment of the present disclosure. The apparatus 200 comprises a magnet holder 208. The magnet holder 208 may be provided in an elongated structure. Further, the magnet holder 208 is provided as a movable structure. For example, the magnet holder 208 is provided to move at any angle that lies between 0 degree and 45 degree with respect to Y-Y axis of the magnet holder 208. The magnet holder 208 may made of a non-metallic material such as brass, steel and so on. The magnet holder 208 comprises a magnet 210. The magnet 210 is provided in axial form for i producing axial magnetic field. The magnet holder 208 and the float arm 206 are coupled via an adjustable mechanical joint (not shown) such as spider joint. Due to the placement of the magnet

210 in the magnet holder 208, the magnetic field does not vary with respect to magnetic drift, temperature differences, and air gap produced while the magnet holder 208 rotates about its axis.
[035] Further, the apparatus 200 comprises a hall sensor 214. The hall sensor 214 comprises plates (not shown). The plates may be provided in a square or rectangular or circular or any other shape. The plates may be made up of a metal such as a cast iron. In one implementation, the hall sensor 214 is provided in proximity to the magnet holder 208. The magnet 210 rotates about its axis in the magnet holder 208 with respect to the hall sensor 214 i.e., when the magnet 210 comes in proximity to the plates of the hall sensor 214, the magnet 210 rotates about the axis of the magnet 210 within the magnet holder 208. Further, the hall sensor 214 comprises an angle sensor (not shown) for determining angular distance from the magnet holder 208.
[036] The apparatus 200 comprises a positive terminal 216 and a negative terminal 218, collectively termed as terminals 216, 218. The terminals 216, 218 are powered by a power unit (not shown). The terminals 216, 218 are provided for receiving an input voltage 3.0 to 12V from the power unit and then transferring the input voltage to the hall sensor 214 via the terminals 216,218.
[037] The apparatus 200 further comprises a Printed Circuit Board (PCB) 220 for providing an output voltage. The hall sensor 214 is electrically coupled to the Printed Circuit Board (PCB) 220. In one example, the hall sensor 214 may provide with a linear program for identifying differences between the output voltages generated by the PCB 220. The output voltage is directly proportional to the intensity of the magnetic field.
[038] The manner in which the apparatus 200 operates to determine the level of fuel in the reservoir 100 is described in detail with reference to Figure 5, in accordance with one exemplary embodiment of the present disclosure.
[039] As can be seen in Figure 5, the float object 204 may rest on the surface of the fuel 110 at different levels e.g., at level 505 and level 510. when the float object 204 floats at level (may be 505 or 510), the magnet holder 208 also rotates and covers an angular distance with respect to

axis Y-Y. As described above, the magnet holder 208 and the float arm 206 are coupled via the adjustable mechanical joint. It should be understood that the movement of the magnet holder 208 is based on the movement of the float arm 206 in the reservoir 100
[040] In one example, when the float object 204 comes at level 510, the magnet holder 208
rotates at approximately 45 degree with respect to axis Y-Y. Further, the magnet holder 208 comes in proximity to the hall sensor is placed 214. As a result, the hall sensor 214 measures/detects a relatively large intensity of the magnetic field of the magnet 210.
[041] On the other hand, when the float object 204 comes at level 505, the magnet holder 208 is placed at 0 degree with respect to axis Y-Y, and the magnet 210 turns away the proximity to the hall sensor 214. As a result, the hall sensor 214 measures/detects low intensity of the magnetic field from the magnet 210.
[042] In one example, the hall sensor 214 works on a Hall Effect principle. Accordingly, the hall sensor 214 measures the magnetic field intensity depending on the relative position or orientation of the magnet 210. Based on the magnetic field strength measured, the hall sensor 214 provides an output voltage. Further, the output voltage of the hall sensor 214 is provided to a fuel gauge (not shown). The output voltage corresponding to the intensity of the magnetic field of the magnet (204 is used to determine level of fuel in the reservoir (100). After determining the level of fuel, the fuel gauge is configured to indicate the fuel level readings of the fuel 110 in the reservoir 100.
[043] It is apparent from the above description that the apparatus 200 is used for determining different levels of the fuel 110 in the reservoir 100 in accordance with the variations in the magnetic field of the magnet 210.
[044] The apparatus 200 disclosed in the present disclosure provides linear output with high measurement accuracy and eliminates the possible error due to mechanical contacts.

[045] Even though the apparatus and the method are described to determine the fuel level in the reservoir 100, the apparatus and method may be used or adapted to determine any type of fluid in any type of fluid reservoir.
[046] The written description describes the subject matter herein to enable any person skilled in the art to make and use the embodiments of the invention. The scope of the subject matter embodiments are defined by the claims and may include other modifications that occur to those skilled in the art. Such other modifications are intended to be within the scope of the claims if they have similar elements that do not differ from the literal language of the claims or if they include equivalent elements with insubstantial differences from the literal language of the claims.

Reference Numerals:
Reservoir 100
Opening 105
Fuel 110
Apparatus 200
Float Object 204
Float Arm 206
Magnet Holder 208
Magnet 210
Hall sensor 214
Positive terminal 216
Negative terminal 218
Printed Circuit Board (PCB) 220
Fuel levels 505, 510

WE CLAIM:
1. An apparatus (200) for determining level of fuel (110) in a reservoir (100), the apparatus (200)
comprising:
a magnet holder (208) comprising a magnet (210), wherein the magnet holder (208) includes an elongated structure and the magnet (210) is housed at one end of the magnet holder (208), wherein rotating the magnet holder (208) rotates the magnet (210);
a hall sensor (214) provided in proximity to the magnet (210), wherein the magnet (210) induces magnetic field with respect to the hall sensor (214);
a float object (204) placed on surface of the fuel (110) in the reservoir (100); and a float arm (206) coupled to the float object (204) and the magnet holder (208), wherein the float arm (206) engages the magnet holder (208) with respect to the position of the float object (204) on surface of the fuel (110) in the reservoir (100) such that the magnet holder (208) rotates the magnet (210) and the magnet (210) comes in proximity to the hall sensor (214), wherein the hall sensor (214) provides an output voltage corresponding to the intensity of the magnetic field of the magnet (210), and wherein the output voltage is used to determine level of fuel (110) in the reservoir (100).
2. The apparatus (200) as claimed in claim 1, wherein the magnet (210) is provided in an axial form for producing axial magnetic field
3. The apparatus (200) as claimed in claim 1, wherein the hall sensor (214) comprises an angle sensor for determining angular distance of the magnet holder (208).
4. The apparatus (200) as claimed in claim 1, wherein the hall sensor (214) comprises a positive terminal (216) and a negative terminal (218) to receive electric charge from a battery.
5. The apparatus (200) as claimed in claim 1, wherein the hall sensor (214) is electrically coupled to a Printed Circuit Board (PCB) (220) for providing the output voltage.

6. The apparatus (200) as claimed in claim 1, wherein the hall sensor (214) is provided with a linear program for identifying a difference between the output voltages, wherein the output voltage is directly proportional to the intensity of the magnetic field.
7. The apparatus (200) as claimed in claim 1, wherein the hall sensor (214) is electrically coupled to a fuel gauge for indicating the level of the fuel (110) in the reservoir (100).
8. The apparatus (200) as claimed in claim 1, wherein the magnet holder (208), the magnet (210) and the hall sensor (214) are provided in the apparatus (200).