Description:Complete Specification:
The following specification describes and ascertains the nature of this invention and the manner in which it is to be performed:

Field of the invention:
[0001] The present disclosure relates to a device and method to detect clogging of a filter in Exhaust Gas Treatment (EGT) system.

Background of the invention:
[0002] In an Exhaust Gas Treatment (EGT) system, when a main filter of supply module gets clogged, it will be detected as pressure drop error and upon continuous pressure drops, the vehicle will be subjected to limited operating condition (Limp home mode).

[0003] According to a prior art 202041006254 a method to detect a degree of filter clogging in a Diesel Exhaust Fluid (DEF) filter is disclosed. The prior art proposes the method for detecting a degree of filter clogging in a DEF filter of a Selective Catalytic Reduction (SCR) module. An Electronic control unit (ECU) of a vehicle is adapted to detect a degree of clogging in DEF filter. In first step, the ECU receives measured values of a set of parameters from one or more sensors provided in the SCR module. In second step the ECU compares the received values with a set of pre-determined data points stored in the ECU. In a third step, the ECU indicates the value of degree of filter clogging in DEF filter to the vehicle user.

Brief description of the accompanying drawings:
[0004] An embodiment of the disclosure is described with reference to the following accompanying drawing,
[0005] Fig. 1 illustrates an Exhaust Gas Treatment (EGT) system and a device to detect clogging of a main filter of a supply module in the EGT system, according to an embodiment of the present invention, and
[0006] Fig. 2 illustrates a method for determining clogging of a main filter in the EGT system, according to the present invention.

Detailed description of the embodiments:
[0007] Fig. 1 illustrates an Exhaust Gas Treatment (EGT) system and a device to detect clogging of a main filter of a supply module in the EGT system, according to an embodiment of the present invention. The EGT system 100 comprises the supply module 102 to circulate/supply a Diesel Exhaust Fluid (DEF) from a storage tank 108. The supply module 102 comprises a pump 104 and valve arrangement, which takes in DEF from the tank 108 through a pre-filter y suction, and pressurizes and circulates further. The EGT system 100 also comprises a dosing module 112 to deliver/inject the DEF into an exhaust path 114. The DEF is supplied by the supply module 102 through a main filter 106. A backflow connection is also provide through one-way valve back to the tank 108. Further, a control unit 110 is connected to operate the supply module 102 and the dosing module 112 as per the requirement, characterized in that, a resistor 116 (such as a shunt resistor) connected in series with a power supply line 122 of the supply module 102. A parameter associated with at least one of the resistor 116 and the supply module 102 is monitored to determine clogging of the main filter 106.

[0008] In accordance to an embodiment of the present invention, the parameter is at least one of a current through the resistor 116, a voltage across the resistor 116 and a duty cycle of a pump 104 in the supply module 102.

[0009] According to an embodiment of the present invention, a controller 124 in the EGT system 100 to determine the clogging is provided. The controller 124 configured to detect variations in the parameter beyond a threshold value, compare the detected variation with respect to a look-up table stored in a memory element of the controller 124, and determine clogging of the main filter 106 based on the comparison. In accordance to an embodiment, the controller 124 is further configured to determine a level of clogging based on detected variation of the parameter, and indicate the clogging level through brightness level of a light indicator 118 on a dashboard of the vehicle or through digital instrument cluster. Any other indicator 118 such as audio, haptic is also usable.

[0010] According to the present invention, the controller 124 is provided with necessary signal detection, acquisition, and processing circuits. The controller 124 is the control unit which comprises input/output interfaces having pins or ports, a memory element (not shown) such as Random Access Memory (RAM) and/or Read Only Memory (ROM), Analog-to-Digital Converter (ADC) and a Digital-to-Analog Convertor (DAC), clocks, timers, counters and at least one processor (capable of implementing machine learning) connected with each other and to other components through communication bus channels. The memory element is pre-stored with logics or instructions or programs or applications or modules/models and/or threshold/safe limit values/ranges, which is/are accessed by the at least one processor as per the defined routines. The internal components of the controller 124 are not explained for being state of the art, and the same must not be understood in a limiting manner. The controller 124 may also comprise communication units to communicate with ECU of the vehicle through wireless or wired means such as Global System for Mobile Communications (GSM), 3G, 4G, 5G, Wi-Fi, Bluetooth, Ethernet, serial networks, Controller Area Network (CAN), and the like. The controller 124 is implementable in the form of System-in-Package (SiP) or System-on-Chip (SOC) or any other known types as the Engine Control Unit itself or external control unit interfaced with the Engine Control Unit.

[0011] In accordance to an embodiment of the present invention, the EGT system 100 is suitable to be used in vehicle such as a four-wheeler such as car, and other vehicles such as trucks, buses, off road vehicles etc.

[0012] In accordance to an embodiment of the present invention, a device 120 to detect clogging of main filter 106 in an Exhaust Gas Treatment (EGT) system 100 is provided. The EGT system 100 comprises the supply module 102 to circulate/supply the DEF from the storage tank 108, and the dosing module 112 to inject/dose/deliver the DEF supplied by the supply module 102 into the exhaust path 114, the DEF is supplied through the main filter 106, characterized in that, the device 120 comprises the resistor 116 connected in series with the power supply line 122 of the supply module 102, and the controller 124 configured to monitor the parameter associated with at least one of the resistor 116 and the supply module 102 and determine clogging of the main filter 106.

[0013] In accordance to an embodiment, the parameter is at least one of the current through the resistor 116, the voltage across the resistor 116 and the duty cycle of the pump 104 in the supply module 102. The measurement of current and voltage is performed as known in the art and the same must not be understood in limiting manner.

[0014] According to the present invention, the controller 124 configured to detect variations in the parameter beyond a threshold value, compare the detected variation with respect to the look-up table stored in the memory element of the controller 124, and determine clogging of the main filter 106 based on the comparison. The controller 124 is further configured to determine a level of clogging based on the detected variation, and indicate the clogging level through brightness level of a light indicator 118 on the dashboard of the vehicle or through the digital instrument cluster of the vehicle.

[0015] An example of the parameters is provided for clarity. For example, the threshold value for current comprises a first current threshold which when breached confirms the start of clogging of say 20%. If the measured current exceeds a second current threshold, then clogging is at 40%. If the measured current exceeds a third current threshold, then the clogging is at 70% and the like. Similar threshold values are set for all parameters. The controller 124 also checks the duration of the measured parameter and if the duration is also exceeded, then the clogging is confirmed with corresponding level of clogging.

[0016] According to the present invention, a working of the EGT system 100 and the device 120 is provided. Consider the vehicle is in operation and being driven on a roadway. Consider the main filter 106 in the path between the pump 104 of the supply module 102 has started to clog after a long usage. Due to clogging, the pump 104 needs to be put more power to pump the required amount to the dosing module 112 in comparison to the power required for the same amount during unclogged filter. This leads to increase in duty cycle which is monitored by the control unit 110 of the EGT system 100. Further, the increase in duty cycle also causes increase in load current through the resistor 116. The controller 124 receives the measured duty cycle from the control unit 110 or directly from the pump 104 or the supply module 102. The increase in load current also causes increased voltage drop across the resistor 116. The parameters comprising the measured current, measured voltage and the measured duty cycle are received by the controller 124 and processed with stored look-up table to confirm the clogging. Alternatively, instead of the look-up table, the controller 124 comprises a model which when fed with the input as the value of the parameter, the output is obtained as the clogging detected or not. Further, the controller 124 also provides the details of the level of clogging based on the value of the parameter. The model is either based on simple mathematical function or based on machine learning algorithms. Once the clogging and level of clogging is determined, the same is notified to the driver, user, operator through the visual means in the cabin such as light indicator 118 or digital instrument cluster.

[0017] Fig. 2 illustrates a method for determining clogging of a main filter in the EGT system, according to the present invention. The EGT system 100 comprises, the supply module 102 to circulate/supply the DEF from the storage tank 108, and the dosing module 112 to inject/dose/deliver the DEF supplied by the supply module 102 through the main filter 106, to the exhaust path 114. The method is characterized by plurality of steps of which a step 202 comprises detecting, by the controller 124, variations in the parameter beyond the threshold value. A step 204 comprises comparing, by the controller 124, the detected variation with respect to the look-up table stored in the memory element of the controller 124. Alternatively, a model is usable for determination of clogging. A step 206 comprises determining, by the controller 124, clogging of the main filter 106 based on the comparison. The parameter is monitored for at least one of the supply module 102 and the resistor 116 connected in series with the power supply line 122 of the supply module 102. The method further comprises a step 208 for determining the level of clogging based on the detected variation. A step 210 comprises indicating the clogging level through brightness level of the light indicator 118 on the dashboard of the vehicle or through the digital instrument cluster of the vehicle.

[0018] According to the method, the parameter is at least one of the current through the resistor 116, the voltage across the resistor 116 and the duty cycle of the pump 104 of the supply module 102.

[0019] According to the present invention, the main filter 106 clogging detection in EGT system 100 is provided by using shunt resistor 116. The driver/operator gets indication of filter clogging at different percentage of clogging conditions on the dash board. A filter replacement alert is issued which prevents the vehicle going into limited operating mode. The EGT system 100 consist of the supply module 102, the dosing module 112, control unit 110, pressure line, wiring harness, etc. The filter clogging detection and indication layout is added additionally to the existing EGT system 100 which as per the present invention consists of wiring harness, shunt resistor 116 and indicator 118 (optional). The indication is provided in the dashboard through an externally fit light indicator 118 or through the digital instrument cluster. In an alternative, the method is programmable and implementable through the ECU, the signals are sent to cluster when the main filter 106 is clogged.

[0020] It should be understood that embodiments explained in the description above are only illustrative and do not limit the scope of this invention. Many such embodiments and other modifications and changes in the embodiment explained in the description are envisaged. The scope of the invention is only limited by the scope of the claims.
, Claims:We claim:
1. An Exhaust Gas Treatment (EGT) system (100) for a vehicle, said EGT system (100) comprises:
a supply module (102) to circulate a Diesel Exhaust Fluid (DEF) from a storage tank (108), and
a dosing module (112) to deliver said DEF into an exhaust path (114), said DEF is supplied by said supply module (102) through a main filter (106), characterized in that
a shunt resistor (116) connected in series with a power supply line (122) of said supply module (102), wherein a parameter associated with at least one of said resistor (116) and said supply module (102) is monitored to determine clogging of said main filter (106).

2. The EGT system (100) as claimed in claim 1, wherein said parameter is at least one of a current through said resistor (116), a voltage across said resistor (116) and a duty cycle of a pump (104) in said supply module (102).

3. The EGT system (100) as claimed in claim 1, comprises a controller (124) to determine said clogging, said controller (124) configured to
detect variations in said parameter beyond a threshold value,
compare said detected variation with respect to a look-up table stored in a memory element of said controller (124), and
determine clogging of said main filter (106) based on said comparison.

4. The EGT system (100) as claimed in claim 3, wherein said controller (124) is configured to,
determine a level of clogging based on detected variation, and
indicate said clogging level through brightness level of a light indicator (118) on a dashboard of said vehicle.

5. A device (120) to detect clogging of main filter (106) in an Exhaust Gas Treatment (EGT) system (100), said EGT system (100) comprises
a supply module (102) to circulate a Diesel Exhaust Fluid (DEF) from a storage tank (108), and
a dosing module (112) to deliver said DEF supplied by said supply module (102) into an exhaust path (114), characterized in that, said device (120) comprises
a resistor (116) connected in series with a power supply line (122) of said supply module (102), and
a controller (124) configured to monitor a parameter associated with at least one of said resistor (116) and said supply module (102) and determine clogging of said main filter (106).

6. The device (120) as claimed in claim 5, wherein said parameter is at least one of a current through said resistor (116), a voltage across said resistor (116) and a duty cycle of a pump (104) in said supply module (102).

7. The device (120) as claimed in claim 5, wherein said controller (124) configured to
detect variations in said parameter beyond a threshold value,
compare said detected variation with respect to a look-up table stored in a memory element of said controller (124), and
determine clogging of said main filter (106) based on said comparison.

8. The device (120) as claimed in claim 7, wherein said controller (124) is configured to,
determine a level of clogging based on said detected variation, and
indicate said clogging level through brightness level of a light indicator (118) on a dashboard of a vehicle.

9. A method for determining clogging of a main filter (106) in an Exhaust Gas Treatment (EGT) system (100), said EGT system (100) comprises, a supply module (102) to circulate a Diesel Exhaust Fluid (DEF) from a storage tank (108), and a dosing module (112) to deliver said DEF supplied by said supply module (102) into an exhaust path (114), characterized by, said method comprises the steps of:
detecting, by a controller (124), variations in a parameter beyond a threshold value,
comparing, by said controller (124), said detected variation with respect to a look-up table stored in a memory element of said controller (124), and
determining, by said controller (124), clogging of said main filter (106) based on said comparison,
wherein said parameter is related to at least one of a supply module (102) and a resistor (116) connected in series with a power supply line (122) of said supply module (102).

10. The method as claimed in claim 9, wherein said parameter is at least one of a current through said resistor (116), a voltage across said resistor (116) and a duty cycle of a pump (104) of said supply module (102).