Description:TECHNICAL FIELD

Present disclosure generally relates to the field of automobiles. Particularly, but not exclusively, the present disclosure relates to replacement of air filter element in a vehicle. Further, embodiments of the present disclosure describe a method and a system for indicating replacement of the air filter element in the vehicle.

BACKGROUND OF THE INVENTION

Generally, vehicles employing internal combustion engines require air to be mixed with fuel for combustion and in-turn maneuver such vehicles. Air is drawn from the surrounding atmosphere and is pressurized inside the engine to ensure combustion of fuel. The air present in the atmosphere includes contaminants such as, particulate matter, dust, smog, and other suspended substances which may affect performance of the internal combustion engine.

To ensure that the air drawn into the internal combustion engine is clean and free from contaminants, generally an air filter assembly is employed in the vehicles, through which the air is drawn . The air filter assembly includes an air filter element, which is employed to filter the unwanted particles. Further, vehicles that generally operate in regions having high degree of contaminants, for example, mines, construction sites or agricultural locations, may have to filter more contaminants than those which may be employed for cruising in plain terrain. Consequently, the replacement intervals for air filter elements may vary for different vehicles and is also dependent on the operating conditions of the vehicle.

Conventionally, air filter elements in vehicles were replaced after a pre-determined time period or after the vehicle traverses for a pre-determined distance or with the help of a mechanical service indicator which indicates air filter element choked condition when pressure drop reaches certain defined threshold. However, replacing air filters in the above manner may not be feasible since air filter degradation may vary based on the driving conditions and the environment in which the vehicle is used. All the conventional methods are mechanical in nature. Therefore, replacement of air filters may often be delayed, and the vehicle is often forced to operate with clogged air filters. Clogged air filters often starve the engine by supplying less filtered air than the required volume. Consequently, the performance and fuel efficiency of the vehicle is adversely affected. Further, combustion of fuel in the engine is partial due to the lack of availability of filtered air. Therefore, emissions from the engine of the vehicle increases due to insufficient combustion of fuel in the engine. Further, the impurities often tend to damage the engine resulting in frequent servicing or frequent replacement of major parts in the engine. Thus, the maintenance cost of the vehicle increases significantly, which is undesired.

Considering the above and with the advancement in technology, pressure sensors are mounted proximal to air filters. The pressure sensors measure the pressure in the airflow path before and ahead of the air filter. Based on pressure difference from the obtained pressure values, clogging extent or life of the air filter determined. However, such techniques require external sensors to be mounted, leading to packaging constraints, increased cost, which is again undesired.

The present disclosure is directed to overcome one or more limitations stated above or any other limitations associated with the conventional configuration of air intake system.

SUMMARY OF THE DISCLOSURE

One or more shortcomings of the conventional system or method are overcome, and additional advantages are provided through the provision of the method as claimed in the present disclosure.

Additional features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail and are considered a part of the claimed disclosure.

In a non-limiting embodiment of the disclosure, a method of indicating replacing of an air filter element in a vehicle is disclosed. The method includes aspects of receiving by a control unit, a signal from a first sensor associated with an intake manifold of the vehicle where, the signal corresponds to a first intake manifold pressure at Ignition ON and an engine OFF condition. The control unit further receives a signal from the first sensor, corresponding to a second intake manifold pressure during at least one operating condition of the engine. The control unit determines a pressure drop at the intake manifold based on the received first intake manifold pressure and the second intake manifold pressure. Further, the control unit compares the determined pressure drop with a pre-determined threshold pressure. The control unit operates an indication unit for indicating the replacing of the air filter element, when the pressure drop at the intake manifold exceeds the pre-determined threshold pressure.

In a non-limiting embodiment of the disclosure, the control unit receives the signal corresponding to the first intake manifold pressure at ignition ON condition and at engine OFF condition.

In an embodiment of the disclosure, the at least one operating condition of the vehicle corresponds to one of engine speed exceeding a predetermined threshold engine speed and a throttle valve opened beyond a predetermined threshold opening within a throttle body.

In an embodiment of the disclosure, the predetermined threshold engine speed is equivalent to the speed of the engine operating at maximum power.

In an embodiment of the disclosure, the predetermined threshold opening of the throttle valve within the throttle body is open more than 90%.

In an of the disclosure, the control unit determines the pressure drop based on difference between the first intake manifold pressure and the second intake manifold pressure.

In an of the disclosure, the control unit records a count corresponding to number of times the pressure drop is greater than the pre-determined threshold pressure.

In an embodiment of the disclosure, the control unit indicates replacing of the air filter element when the recorded count exceeds a predetermined threshold count which ranges from 2 to 5.

In an embodiment of the disclosure, the control unit indicates replacing of the air filter element through an indication unit which is one of an audio signal and a visual signal.

In an embodiment of the disclosure, the control unit detects replacing of the air filter element, when the pressure drop becomes less the pre-determined threshold pressure after the threshold count and sets the count to zero upon detecting replacing of the air filter element.

In an embodiment of the disclosure, the first sensor associated with the intake manifold of the engine is a manifold absolute temperature-pressure sensor.

In another non-limiting embodiment of the disclosure, a system for indicating an air filter element replacement in a vehicle is disclosed. The system includes a first sensor associated with an intake manifold of an engine in the vehicle and a control unit communicatively coupled to the first sensor. The control unit is configured to receive a signal from a first sensor associated with an intake manifold of the vehicle where the signal corresponds to a first intake manifold pressure at Ignition ON and an engine OFF condition. The control unit further receives a signal from the first sensor, corresponding to a second intake manifold pressure during at least one operating condition of the engine. The control unit determines a pressure drop at the intake manifold based on the received first intake manifold pressure and the second intake manifold pressure. Further, the control unit compares the determined pressure drop with a pre-determined threshold pressure. The control unit operates an indication unit for indicating the replacing of the air filter element, when the pressure drop at the intake manifold exceeds the pre-determined threshold pressure.

The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE ACCOMPANYING FIGURES

The novel features and characteristics of the disclosure are set forth in the appended claims. The disclosure itself, however, as well as a preferred mode of use, further objectives, and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying figures. One or more embodiments are now described, by way of example only, with reference to the accompanying figures wherein like reference numerals represent like elements and in which:

Figure 1 illustrates a block diagram of a system for indicating replacement of an air filter element in a vehicle, in accordance with an embodiment of the disclosure.

Figure 2 is a flowchart of a method for indicating the replacing of the air filter element in the vehicle, in accordance with an embodiment of the disclosure.

Figure 3 is a flowchart of a method for resetting a counter after replacing a choked air filter element.

The figure depicts embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the method for pre-heating an exhaust gas after treatment unit without departing from the principles of the disclosure described.

DETAILED DESCRIPTION

The foregoing has broadly outlined the features and technical advantages of the present disclosure in order that the description of the disclosure that follows may be better understood. Additional features and advantages of the disclosure will be described after which form the subject of the disclosure. It should be appreciated by those skilled in the art that the conception and specific embodiments disclosed may be readily utilized as a basis for modifying or designing other systems for carrying out the same purposes of the present disclosure. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the disclosure. The novel features which are believed to be characteristic of the disclosure, as to its organization, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present disclosure.

In the present document, the word “exemplary” is used to mean “serving as an example, instance, or illustration.” Any embodiment or implementation of the present subject matter described as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.

While the disclosure is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and will be described below. It should be understood, however, that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternative falling within the scope of the disclosure.

The terms “comprises”, “comprising”, or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a system that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such mechanism. In other words, one or more elements in the device or mechanism proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the mechanism.

The following paragraphs describe the present disclosure with reference to Figures. 1 and 2. In the figures, the same element or elements which have the same functions are indicated by the same reference signs. It is to be noted that, the vehicle including powertrain and the chassis is not illustrated in the figures for the purpose of simplicity. One skilled in the art would appreciate the method and system for indicating the replacing of the air filter element in the vehicle as disclosed in the present disclosure that may be used in any vehicles that employs/includes combustion engines, where such vehicles may include, but not be limited to, light duty vehicles, passenger vehicles, commercial vehicles, heavy duty vehicles and the like.

Figure. 1 illustrates a system (100) for indicating replacement of an air filter element (1) for an internal combustion engine (6) of a vehicle. The vehicle may include but not limited to passenger vehicles, utility vehicles, commercial vehicles, heavy duty vehicles and any other vehicle having an internal combustion (IC) engine (6) [after referred as engine], as a prime mover. Further, the engine (6) of the vehicle may be fluidly connected to an air intake assembly. The air intake system may be configured to direct an incoming stream of air into the engine. The air intake system may include an inlet conduit [not shown] which is adapted to receive air from the surrounding atmosphere. Further, the air intake system may include a snorkel [not shown in figures], extending from an end of the inlet conduit. In an embodiment, the snorkel may be configured to filter large particles stone pellets, leaves, polythene bags and any other unwanted large particles which need to be restricted from entering the vehicle intake system. Further, the snorkel may be positioned such that water, and any other liquids in the surrounding of the air intake system are prevented from entering. Furthermore, the air intake system includes an air filter element (1) disposed in a portion of the inlet conduit. In an embodiment, the air filter element (1) may be configured to filter the air received from the inlet conduit before channelizing the air into the engine (6). That is, the contaminants may initially be filtered from the air in the air filter element (1) and post filtering, the clean air may be channelized to an intake manifold through an outlet conduit of the air filter element (1). As apparent from Figure. 1, the air intake system may further include an intake manifold (5), which may be fluidly coupled to the air filter element (1) through an outlet conduit and) may be configured to guide or direct the clean/filtered air from the air filter element (1) into the engine (6) of the vehicle.

The air intake system may also include a throttle valve (8). The throttle valve (8) in a preferable but not limiting embodiment may be positioned between the outlet conduit of the air filter element (1) and the intake manifold (5). The throttle valve (8) may be connected to an accelerator pedal of the vehicle. The depression of the accelerator pedal may proportionally open/rotate the throttle valve (8). The throttle valve (8) may rotate and may allow the flow of clean air into the intake manifold (5). Further, the degree of rotation of the throttle valve (8) may be dependent on the extent to which the accelerator pedal is pressed. The complete pressing of the accelerator pedal may cause the throttle valve (8) to rotate and allow the complete/un-restricted flow of air from the air filter element (1) into the intake manifold (5).

Referring further to Figure. 1, the system (100) may further include a first sensor (3). The first sensor (3) may be associated with the intake manifold (5). As an example, the first sensor (3) may be but not limiting may be a manifold absolute temperature-pressure sensor (TMAP/MAP sensor), which may be configured to determine pressure in the intake manifold. The first sensor (3) is an integral and pre-existing part of the internal combustion spark ignited (SI) engine (6) which is accommodated in the intake manifold (5) of the engine (6). The first sensor (3) may be configured to detect a pressure in the intake manifold during Ignition ON and OFF condition of the engine and at least one operating condition of the engine. As an example, the at least one operating condition of the engine is one of engine (6) speed exceeding a predetermined threshold engine speed and a throttle valve being opened beyond a predetermined threshold opening within a throttle body. Furthermore, the system (100) may include a control unit (2), which may be communicatively coupled to the first sensor (3). The control unit (2) may be configured to receive a signal from the first sensor (3) that corresponds to the detected pressure in the intake manifold (5) during Ignition ON and OFF condition of the engine (6) and at least one operating condition of the engine (6).

In an embodiment, the system (100) may include a second sensor (7) which may be associated with the engine (6) of the vehicle and communicatively coupled to the control unit (2). The second sensor (7) may be configured to detect the engine speed. The second sensor (7) may also be a pre-existing component in the engine (6) and as an example, the second sensor may be a speed sensor. The second sensor (7) may be configured to detect the engine speed by means including but not limited to measuring the revolutions per minute (RPM) of the crankshaft. The control unit (2) may be configured to receive signals from the second sensor (7) which corresponds to the operational speed of the engine (6). In an embodiment, the system (100) may further include a third sensor (9). The third sensor (9) may be associated with the throttle valve (8) and may be communicatively coupled to the control unit (2). The third sensor (9) may be configured to detect the extent to which the throttle valve (8) is open. The control unit (2) may be configured to receive signals from the third sensor (9) that corresponds to the extent to which the throttle (8) is open to allow the flow of air into the intake manifold (5).

In an operational embodiment, the control unit (2) receives a signal from the first sensor (3) associated with the intake manifold (5) of the vehicle where, the signal corresponds to a first intake manifold pressure (P1) at Ignition ON and engine OFF condition. The control unit (2) further receives a signal from the first sensor (3), corresponding to a second intake manifold pressure (P2) during at least one operating condition of the engine (6). The operating condition of the vehicle corresponds to one of engine speed exceeding a predetermined threshold engine speed and a throttle valve opened beyond a predetermined threshold opening within a throttle body. The control unit (2) may be configured to detect the engine speed through the signal from the second sensor (7) and the throttle valve position may be detected through the signal from the third sensor (9). The control unit (2) determines the pressure drop (PD) at the intake manifold (5) based on the received first intake manifold pressure (P1) and the second intake manifold pressure (P2). Further, the control unit (2) compares the determined pressure drop (PD) with a pre-determined threshold pressure (PT). The control unit (2) operates the indication unit (4) for indicating the replacing of the air filter element (1), when the pressure drop (PD) at the intake manifold (5) exceeds the pre-determined threshold pressure (PT). Further, the control unit (2) may be pre-fed with values that correspond to the pre-determined threshold pressure (PT) of the intake manifold (5).

Turning now to Figure. 2 which is a flowchart of a method executed by the system (100) for indicating the replacing of the air filter element (1) in the vehicle. The method includes a first step 201 of detecting if the ignition of the vehicle is in an ON condition and engine is in OFF condition. The control unit (2) may be configured to receive a signal that corresponds to the ignition ON and engine off condition. Subsequently, the control unit (2) may be configured receive a signal from the first sensor (3). The first sensor (3) may transmit a signal that corresponds to the pressure in the intake manifold (5). The pressure in the intake manifold (5) during ignition ON and engine off condition may be referred to as the first intake manifold pressure (P1).

Further, the control unit (2) checks if the engine (6) is in an ON condition. The control unit (2) may be configured to receive a signal that corresponds to the engine (6) ON condition. The control unit (2) may receive the signal from the first sensor (3) for determining the engine ON condition of the vehicle. The first sensor (3) may transmit a signal as the pressure in the intake manifold increases. As the engine is turned ON/cranked by an operator, the air filter element (1) begins to filter the air and the clear air is further circulated into the intake manifold (5). As the clean air flows into the intake manifold (5), the pressure in the intake manifold (5) increases. Subsequently, the control unit (2) may receive the corresponding signal from the first sensor (3) which is indicative of the increase in the pressure in the intake manifold (5) which further indicates the engine ON condition. In an embodiment, the control unit (2) detecting the engine ON condition must not be limited through the first sensor (3). The control unit (2) may be configured to receive signal from other sensors including but not limited to torque sensor, engine temperature sensor etc. for determining if the engine is in ON condition. Further, if the control unit (2) fails to receive the signal which corresponds to the engine ON condition, the control unit (2) checks for the ignition ON condition in step 201. If the control unit (2) receives the signal that corresponds to the engine ON condition, the control unit shall proceed to step 202.

The control unit (2) in step 202 may receive the signal from the first sensor (3) that corresponds to the pressure in the intake manifold (5) when the engine (6) of the vehicle is in the ON condition. Further, the control unit (2) may be configured to record the pressure in the intake manifold (5) when at least one operating condition of the vehicle corresponds to one of engine (6) speed exceeding a predetermined threshold engine speed and a throttle valve opened beyond a predetermined threshold opening within a throttle body.

In an embodiment, the pre-determined threshold of the engine speed may be defined as the band close to maximum operational speed of the engine (6). The maximum operational speed of the engine (6) may further be defined as maximum revolutions per minute of a crankshaft in the engine (6). In an exemplary embodiment, the predetermined threshold engine speed is equivalent to the speed of the engine operating at maximum power. In an exemplary embodiment, the maximum revolutions of the crankshaft in the engine (6) ranges from 3000 revolutions per minute of the crankshaft to 4500 revolutions per minute of the crankshaft.

Further, the pre-determined threshold opening of the throttle valve (8) in the throttle body may be defined as the maximum limit/extent to which the throttle valve (8) is opened in the throttle body. In embodiment, the pre-determined threshold opening of the throttle valve (8) may be defined as the opening of the throttle valve (8) that extends beyond 90% open. In an embodiment, the control unit (2) may also be configured to receive signals from the third sensor (9) which may be associated with the throttle valve (8). The third sensor (9) may be configured to transmit a signal to the control unit (2) when the throttle valve (8) is open beyond the pre-determined threshold opening or when the throttle valve (8) is in the fully open state/condition.

The control unit (2) may be configured to detect and record the second intake manifold pressure (P2) when the at least one operating condition of the vehicle corresponds to one of engine (6) speed exceeding the predetermined threshold engine speed and the throttle valve (8) being opened beyond the predetermined threshold opening within the throttle body. The control unit (2) may record the pressure in the intake manifold (5) when the control unit (2) receives the signal from at least one of the second sensor (7) and third sensor (9) that correspond to the engine (6) speed exceeding the predetermined threshold engine speed and the throttle valve (8) being opened beyond the predetermined threshold opening, respectively.

In a preferable embodiment, the control unit (2) records the second intake manifold pressure (P2) only when the engine is operating beyond the predetermined threshold engine speed and the throttle valve (8) being opened beyond the predetermined threshold opening. The control unit (2) records the second intake manifold pressure (P2) in the above condition since, the pressure fluctuates/varies when the engine is not operational in the above-described conditions. A vacuum is created in the intake manifold (5) when the engine is not operating beyond the predetermined threshold engine speed or when the throttle valve (8) is not opened beyond the predetermined threshold opening. Due to the vacuum in the intake manifold (5), the pressure drops in the intake manifold (5) and the recorded pressure values are inaccurate. Consequently, the control unit (2) only records the second intake manifold pressure (P2) when the engine is operating beyond the predetermined threshold engine speed and the throttle valve (8) being opened beyond the predetermined threshold opening. In an embodiment, the above operational conditions of the engine (6) must not be considered as a limitation and any condition which is indicative of the engine being operational at maximum power/capacity may be considered for recoding the second intake manifold pressure (P2).

Once the control unit (2) records the second intake manifold pressure (P2) and the first intake manifold pressure (P1), the control unit (2) may determine the pressure drop (PD) at the intake manifold (5) in step 203. The pressure drop (PD) of the intake manifold (5) may be difference between the recorded pressure values of second intake manifold pressure (P2) and the first intake manifold pressure (P1). The estimated pressure drop (PD) of the difference between the second intake manifold pressure (P2) and the first intake manifold pressure (P1) is recorded by the control unit (2).

The control unit (2) in step 204 may compare the determined pressure drop (PD) at the intake manifold (5) with the pre-determined threshold pressure (PT). If the pressure drop (PD) is lesser than the pre-determined threshold pressure (PT), the control unit (2) determines that the air flow in the intake manifold (5) is optimal. The pressure drop (PD) in the intake manifold (5) remains lesser than the pre-determined threshold pressure (PT) when the air filter element (1) is not clogged and the air flow to the engine (6) through the intake manifold (5) remains un-restricted. Consequently, the control unit (2) reverts to step 201 where the ignition ON condition of the vehicle is checked. Further, if the pressure drop (PD) is greater than the pre-determined threshold pressure (PT), the control unit (2) determines that the air flow in the intake manifold (5) is hampered/obstructed. The pressure drop (PD) in the intake manifold (5) remains greater than the pre-determined threshold pressure (PT) when the air filter element (1) is clogged and the air flow to the engine (6) through the intake manifold (5) is restricted.

Upon determining the pressure drop (PD) to be greater than the pre-determined threshold pressure (PT), the control unit (2) records a count (R) in step 205. The count (R) may be numerical, and the control unit (2) is configured to record/store the numerical value when the pressure drop (PD) is determined to be greater than the pre-determined threshold pressure (PT). The control unit (2) is further configured to numerically increase the count (R) every time the pressure drop (PD) is determined to be greater than the pre-determined threshold pressure (PT). For instance, the control unit (2) may numerically record the count (R) as “one” when the pressure drop (PD) is determined to be greater than the pre-determined threshold pressure (PT) for the first time. Further, the control unit (2) may numerically increase the count (R) from “one” to “two” when the pressure drop (PD) is determined to be greater than the pre-determined threshold pressure (PT) for the second instance. The control unit (2) may thus numerically increase the count (R) by one for each instance when the pressure drop (PD) is determined to be greater than the pre-determined threshold pressure (PT).

The control unit (2) may compare the count (R) with the with a pre-determined threshold count (RT). The pre-determined threshold count (RT) may range from a numeric value ranging from 2 to 5. The pre-determined threshold count (RT) in this preferable embodiment may be set to a numerical value of “three”. For instance, when the recorded count is “one”, and when the pressure drop (PD) is determined to be greater than the pre-determined threshold pressure (PT), the control unit (2) may initially compare the count (R) with the pre-determined threshold count (RT). Since, the recorded count of “one” is lesser than the pre-determined threshold count (RT), the control unit (2) may numerically increase the count (R) by a value of “one” for each instance of determining the pressure drop (PD) to be greater than the pre-determined threshold pressure (PT). Further, when the count (R) increases to the value greater than “three”, the control unit (2) compares and determines the recorded count (R) to be greater than the pre-determined threshold count (RT). Subsequently, the control unit (2) may operate an indication unit (4). The indication unit (4) provides an indication for replacing of the air filter element (1) and the indication signal may be any type of signal including but not limited to an audio signal, a visual signal etc.

Reference is made to Figure 3 which illustrates a method of resetting the count in the control unit (2) after the replacement of the air filter element (1) in the vehicle. As described above and subsequent to replacing of the air filter element (1) in step 205, the control unit (2) may re-check if the pressure drop (PD) in the intake manifold (5) is lesser than the pre-determined threshold pressure (PT). The control unit (2) may check in the step 206 if the pressure drop (PD) in the intake manifold (5) is lesser than the pre-determined threshold pressure (PT) when the engine is operational at maximum power condition which corresponds to at least one operating condition of the vehicle engine (6) speed exceeds a predetermined threshold engine speed and the throttle valve is opened beyond the predetermined threshold opening. If the pressure drop (PD) in the intake manifold (5) is lesser than the pre-determined threshold pressure (PT) when the engine (6) is operational at the maximum power, the control unit (2) determines that the air filter element (1) is not clogged and the air flow to the engine (6) through the intake manifold (5) remains un-restricted. The control unit (2) may further reset the counter to a numeric value of “zero” in step 207. Once the count (R) is reset to “zero”, the process as described above beginning from the step 201 may be followed again until the air filter element (1) is clogged.

In an embodiment, the third sensor (9) may also be configured to the accelerator pedal of the vehicle. However, the third sensor (9) must not be limited to the sensors associated with the throttle valve (8). In an embodiment, the present disclosure provides a cost-effective arrangement and method for effective tracking and indication for the replacing of the air filter element (1). In an embodiment, the present disclosure provides a method and system for indicating the replacing of the air filter element (1) without using any additional components or sensors and the existing sensor configuration of the vehicle is adapted for indicating the replacing of the air filter element (1). In an embodiment, the present disclosure provides the arrangement and method where the replacing indication is only provided after the count (R) increases beyond the pre-determined threshold count (RT). Consequently, false indications for the replacing of the air filter element (1) are completely reduced/eliminated and premature replacing of the air filter element (1) is avoided which further saves maintenance and repair costs. In an embodiment of the present disclosure, the clogged condition of the air filter element (1) is determined with improved accuracy since, the first pressure in the intake manifold (5)/atmospheric pressure in the intake manifold (5) is calculated in real time and is not a pre-fed value. Consequently, the pressure drop (PD) is calculated with greater accuracy since the pressure is calculated in real time irrespective of the variations in altitude and varying operating environments of vehicle.

Equivalents

With respect to the use of substantially any plural and/or singular terms, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth for sake of clarity.

It will be understood by those within the art that, in general, terms used, are generally intended as "open" terms (e.g., the term "including" should be interpreted as "including but not limited to," the term "having" should be interpreted as "having at least," the term "includes" should be interpreted as "includes but is not limited to," etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding the description may contain usage of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an" (e.g., "a" and/or "an" should typically be interpreted to mean "at least one" or "one or more"); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of "two recitations," without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to "at least one of A, B, and C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, and C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to "at least one of A, B, or C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, or C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase "A or B" will be understood to include the possibilities of "A" or "B" or "A and B."

While various aspects and embodiments have been disclosed, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated in the description.

Referral Numerals:

Referral numerals Description
1 Air filter element
2 Control unit
3 First sensor
4 Indication unit
5 Intake manifold
6 Engine
7 Second sensor
8 Throttle valve
9 Third sensor
100 System
201-207 Method steps
, Claims:We Claim:

1. A method for indicating replacing of an air filter element (1) in a vehicle, the method comprising:
receiving by a control unit (2), a signal from a first sensor (3) associated with an intake manifold (5) of the vehicle, corresponding to a first intake manifold pressure (P1), at Ignition ON and engine (6) OFF condition;
receiving by the control unit (2), a signal from the first sensor (3), corresponding to a second intake manifold pressure (P2) during at least one operating condition of the engine (6);
determining by the control unit (2), a pressure drop (PD) at the intake manifold based on the received first intake manifold pressure (P1) and the second intake manifold pressure (P2);
comparing by the control unit (2), the determined pressure drop (PD) with a pre-determined threshold pressure (PT); and
indicating by the control unit, replacing of the air filter element (1), when the pressure drop (PD) at the intake manifold exceeds the pre-determined threshold pressure (PT).

2. The method as claimed in claim 1, wherein the control unit (2) receives the signal corresponding to the first intake manifold pressure (P1) at ignition ON condition and at engine (6) OFF condition.

3. The method as claimed in claim 1, wherein the at least one operating condition of the vehicle corresponds to one of engine speed exceeding a predetermined threshold engine speed and a throttle valve opened beyond a predetermined threshold opening within a throttle body.

4. The method as claimed in claim 3 wherein, the predetermined threshold engine speed is equivalent to a speed of the engine operating at maximum power..

5. The method as claimed in claim 3 wherein, the predetermined threshold opening of the throttle valve within the throttle body is more than 90% open.

6. The method as claimed in claim 1 wherein, the control unit (2) determines the pressure drop (PD) based on difference between the first intake manifold pressure (P1) and the second intake manifold pressure (P2).

7. The method as claimed in claim 1 comprises, recording by the control unit (2) a count (R) corresponding to number of times the pressure drop (PD) is greater than the pre-determined threshold pressure (PT).

8. The method as claimed in claims 1 and 6, wherein the control unit (2) indicates replacing of the air filter element (1) when the recorded count exceeds a predetermined threshold count which ranges from 2 to 5.

9. The method as claimed in claim 8, wherein the control unit (2) indicates replacing of the air filter element (1) through an indication unit (4) which is one of an audio signal and/or a visual signal.

10. The method as claimed in claims 6 to 8, wherein the control unit (2) detects replacing of the air filter element (1), when the pressure drop (PD) becomes less the pre-determined threshold pressure (PT) after the threshold count and sets the count to zero upon detecting replacing of the air filter element (1).

11. The method as claimed in claim 1 wherein, the first sensor (3) associated with the intake manifold (5) of the engine (6) is a manifold absolute temperature-pressure sensor.

12. A system (100) for indicating replacing of an air filter element (1) in a vehicle, the system (100) comprising:
a first sensor (3) associated with an intake manifold (5) of an engine (6) in the vehicle; and
a control unit (2) communicatively coupled to the first sensor (3), the control unit (2) is configured to:
receive a signal from the first sensor (3) associated with an intake manifold (5) of the vehicle, corresponding to a first intake manifold pressure (P1), at Ignition on and engine (6) OFF condition;
receive a signal from the first sensor (3), corresponding to a second intake manifold pressure (P2) during at least one operating condition of the engine (6);
determine a pressure drop (PD) at the intake manifold based on the received first intake manifold pressure (P1) and the second intake manifold pressure (P2);
compare the determined pressure drop (PD) with a pre-determined threshold pressure (PT); and
indicate replacing of the air filter element (1), when the pressure drop (PD) at the intake manifold exceeds the pre-determined threshold pressure (PT).

13. The system (100) as claimed in claim 12, wherein the first sensor (3) associated with the intake manifold (5) of the engine (6) is a temperature manifold absolute pressure sensor.

14. The system (100) as claimed in claim 12, wherein the at least one operating condition of the vehicle corresponds to one of engine speed exceeding a predetermined threshold engine speed and a throttle valve opened beyond a predetermined threshold opening within a throttle body.

15. The system (100) as claimed in claim 12, the control unit (2) determines intake manifold pressure drop (PD) based on difference between the first intake manifold pressure (P1) and the second intake manifold pressure (P2).

16. The system (100) as claimed in claim 12, wherein the control unit (2) indicates replacing of the air filter element (1) through an indication unit (4) which is one of an audio signal and/or a visual signal