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 tank for storing an aqueous solution in a selective catalytic reduction(SCR) system of a vehicle.

Background of the invention
[0002] Selective Catalytic Reduction (SCR) is an emissions control technology system used in diesel engines to ensure that the exhaust gases are treated and harmful emissions coming out of a vehicle are kept as low as possible. The most popular exhaust gas treatment devices and strategy is dosing an aqueous solution or ad-blue commonly known as Diesel Exhaust Fluid (DEF) to treat oxides of nitrogen. One of the many components of the exhaust gas is different oxides of nitrogen that contribute to the greenhouse effect and other types of contamination. Hence emission norms around the world require that the oxides of nitrogen be treated to convert them to elemental nitrogen before they are let out into the atmosphere. One of the most popular methods of treating the exhaust gases to convert the oxides of nitrogen to elemental nitrogen is by using an aqueous solution.

[0003] The ad-blue or aqueous solution stored in a tank is delivered to a dosing device by means of a supply pump in a supply module. The aqueous solution dosing device is used to dose a metered quantity of the aqueous solution into the exhaust gas path. The metered quantity of the aqueous solution reacts with the oxides of nitrogen and converts it to elemental nitrogen. DEF is stored in the tank mounted on vehicle and through hydraulics and dosing request based on NOx conversion efficiency requirements, DEF is dosed into the exhaust stream. There exists a high probability that during re-filling of DEF tank, instead of DEF, a low-quality solution or a flammable liquid like diesel is filled. In such case system would inject diesel into the exhaust stream. This could damage the system and lead to safety hazard due to uncontrolled burning of diesel in the exhaust line. The effect of misfuelling further results in damage of elastomer membrane of supply pump by swelling effect and damaging the suction of pump. Conventional methods use various algorithms and changes in structure of the SCR system to solve this issue. We propose a new design for the DEF tank to solve this issue.

[0004] Patent application US20150210529A1 “Device for preventing the incorrect filling of a container” discloses A device for preventing the incorrect filling of a container includes a fuel delivery nozzle with an outlet pipe, a container filler neck, into which an end of the fuel nozzle is inserted and a permanent magnet assembly. The magnet assembly includes a first permanent magnet subassembly, with an individual magnet, on one of the outlet pipe and the filler neck and a second permanent magnet subassembly with a plurality of permanent magnets arranged in an annular pattern. The second permanent magnet subassembly is arranged on another of the outlet pipe and the filler neck whereby the first permanent magnet subassembly is arranged radially within the second permanent magnet subassembly, or vice versa, when the fuel nozzle is inserted.

Brief description of the accompanying drawings
[0005] An embodiment of the invention is described with reference to the following accompanying drawings:
[0006] Figure 1 depicts a tank (100) for storing an aqueous solution; and at least
[0007] Figure 2 depicts a selective catalytic reduction(SCR) system (10) for an automobile.

Detailed description of the drawings
[0008] Figure 1 depicts a tank (100) for storing an aqueous solution. The tank (100) comprises two horizontal chambers in an operative position of the tank (100). The horizontal chambers, an upper chamber (101) and a lower chamber (102) are separated by a plate (108). The tank (100) is characterized by the location of the inlet port (103), outlet port (106) and the presence of a quality sensor (104) and an electronically actuated valve (105). The inlet port (103) is located on the upper walls of the upper chamber (101). The outlet port (106) is located on the side walls of the upper chamber (101). The outlet port (106) is proximate to the plate (108) separating the horizontal chambers. A supply module (107) is integrated with the walls of the lower chamber (102) for delivering aqueous solution onward from the tank (100).

[0009] It should be understood at the outset that, although exemplary embodiments are illustrated in the figures and described below, the present disclosure should in no way be limited to the exemplary implementations and techniques illustrated in the drawings and described below.

[0010] The quality sensor (104) is located on the plate (108). The quality sensor (104) is placed on the plate (108) such that it comes in contact with the liquid entering the inlet port (103) first and foremost. The quality sensor (104) in communication with a Dosing Control Unit (DCU (110)). It measures the quality of the aqueous solution entering the upper chamber (101) via the inlet port (103) and communicates the quality information of the aqueous solution to the DCU (110). The quality sensor (104) uses ultrasonic principle to measure the height, temperature and concentration of urea liquid level in the aqueous solution tank (100) in the SCR and send corresponding signals to DCU (110).

[0011] The electronically actuated valve (105) is located on the plate (108), said electronically actuated valve (105) is adapted to provide fluid communication between the upper chamber (101) and the lower chamber (102). In an exemplary embodiment of the present invention the electronically actuated valve (105) is solenoid based valve (105). The electronically actuated valve (105) is normally in a closed position. The DCU (110) operates the electronically actuated valve (105) to an open position in dependance of the quality information received from the quality sensor (104).

[0012] Figure 2 depicts a selective catalytic reduction(SCR) system for an automobile. The SCR system (10) comprises the tank (100) disclosed in accordance with figure 1 and at least the dosing module (130) amongst other components such known to a person skilled in the art. The tank (100) stores an aqueous solution which comprises a diesel exhaust fluid (DEF) which is also known as Ad-blue. It is a liquid reductant agent and usually automotive-grade urea. The supply module (107) disclosed in accordance with figure 1 is fitted inside the operative bottom of a tank (100). In an embodiment of the present disclosure, the supply module (107) is welded on the bottom of the tank (100). The supply module (107) comprises a supply pump and at least a heater. The heater maintains temperature of the aqueous solution ensuring that it remains in a liquid states and doesn’t freeze. The supply pump of the supply module (107) configured to deliver aqueous solution to the dosing module (130)

[0013] The dosing module (130) controls the amount of Ad-blue or DEF that needs to be injected from the tank (100) into an exhaust gas tailpipe. A selective catalytic reduction reaction occurring in the exhaust gas tailpipe converts nitrogen oxides (NOx) into nitrogen, water and tiny amounts of carbon dioxide (CO2) using Ad-blue fluid, thereby reducing NOx emissions. All the components of the SCR system (10) are in communication with the Dosing Control Unit (DCU (110)) of the vehicle. The DCU (110) regulates the dosing quantity of ad-blue by controlling the operation of the dosing module (130).

[0014] The DCU (110) is an electronic circuitry that responds to and processes logical instructions from the SCR system (10). In an alternate embodiment of the present invention, the DCU could be a part of the main Electronic control unit (ECU) of the vehicle. The DCU (110) may be implemented as any or a combination of: one or more microchips or integrated circuits interconnected using a parent board, hardwired logic, software stored by a memory device and executed by a microprocessor (20), firmware, an application specific integrated circuit (ASIC), and/or a field programmable gate array (FPGA) and/or any component that operates on signals based on operational instructions.

[0015] The most important non-limiting feature of present invention is the design of the tank (100). The tank (100) is divided into two partitions. The solenoid valve or any electronically actuated valve (105) acts as a pathway of the flow of AdBlue from upper chamber (101) to lower chamber (102). When fresh AdBlue or DEF is refilled, the filling is done in upper chamber (101). During the working of the SCR system (10) the DCU (110) configured to: receive quality information of the aqueous solution measured by the quality sensor (104); and operate the electronically actuated valve (105) to an open position in dependance of the quality information received from the quality sensor (104).

[0016] The quality sensor (104) in upper chamber (101) continuously monitors the quality of the fluid being filled and sends feedback to the DCU (110). DCU (110) compares feedback signal with the Quality sensor (104) threshold value and send signals to the solenoid valve (105) the upper chamber (101). When the quality is not within the threshold limit, the solenoid valve (105) is closed. Optionally in one embodiment of the present invention, the outlet port (106) is electronically actuated by the DCU (110) to flush out the contaminated fluid. When the quality meets the expected standards the DCU (110) operates the solenoid valve (105) to an open position. In an alternate embodiment of the present invention, the DCU (110) is configured to communicate with an indicating means on the dashboard of the vehicle in dependance of the quality information received from the quality sensor (104).

[0017] This idea to develop a specific design for the tank (100) storing aqueous solution in SCR system (10) aims to provide an improved feature/behavior without allowing the diesel/other liquid to enter the supply pump. This will protect the supply pump component (armature membrane that is made of high-density polyethylene (HDPE) rubber material) when there is accidental fill of diesel or other undesired liquid. Additionally, the DCU (110) with support of on-board diagnosis i.e. the indicating means can show an error on the dashboard and hence inform the driver about the wrong medium in the tank (100).

[0018] It must be understood that the embodiments explained in the above detailed description are only illustrative and do not limit the scope of this invention. Any modification are envisaged and form a part of this invention. The scope of this invention is limited only by the claims.
, Claims:We Claim:
1. A tank (100) for storing an aqueous solution, said tank (100) comprising two horizontal chambers in an operative position of the tank (100), an upper chamber (101) and a lower chamber (102) separated by a plate (108), characterized in that tank (100):
an inlet port (103) located on the upper walls of the upper chamber (101);
an outlet port (106) located on the walls of the upper chamber (101);
a quality sensor (104) located on the plate (108) , said quality sensor (104) in communication with an Dosing Control Unit (DCU (110));
a electronically actuated valve (105) located on the plate (108), said electronically actuated valve (105) adapted to provide fluid communication between the upper chamber (101) and the lower chamber (102), said electronically actuated valve (105) connected to the DCU (110).

2. The tank (100) for storing an aqueous solution as claimed in claim 1, wherein the quality sensor (104) measures quality of the aqueous solution entering the upper chamber (101) via the inlet port (103) and communicates the quality information of the aqueous solution to the DCU (110).

3. The tank (100) for storing an aqueous solution as claimed in claim 1, wherein the electronically actuated valve (105) is normally in a closed position.

4. The tank (100) for storing an aqueous solution as claimed in claim 1, wherein the DCU (110) operates the electronically actuated valve (105) to an open position in dependance of the quality information received from the quality sensor (104).

5. The tank (100) for storing an aqueous solution as claimed in claim 1, wherein a supply module (107) integrated with the walls of the lower chamber (102) for delivering aqueous solution onward from the tank (100).

6. A selective catalytic reduction(SCR) system (10) for an automobile, the SCR system (10) comprising a tank (100) for storing an aqueous solution, a dosing module (130) placed downstream of the tank (100), said dosing module (130) adapted to dose a definite quantity of aqueous solution into exhaust gas pipe (120), the system characterized by:
the tank (100) comprising two horizontal chambers in an operative position of the tank (100), an upper chamber (101) and a lower chamber (102) separated by a plate (108);
an inlet port (103) located on the upper walls of the upper chamber (101);
an outlet port (106) located on the walls of the upper chamber (101);
a quality sensor (104) located on the plate (108), said quality sensor (104) in communication with the DCU (110);
a electronically actuated valve (105) located on the plate (108), said electronically actuated valve (105) adapted to provide fluid communication between the upper chamber (101) and the lower chamber (102), said electronically actuated valve (105) connected to the DCU (110).
a supply module (107) integrated with the walls of the lower chamber (102) of the tank (100), said supply module (107) configured to deliver aqueous solution to the dosing module (130);
the DCU (110) configured to:
receive quality information of the aqueous solution measured by the quality sensor (104);
operate the electronically actuated valve (105) to an open position in dependance of the quality information received from the quality sensor (104).

7. The selective catalytic reduction(SCR) system (10) as claimed in claim 6, wherein the electronically actuated valve (105) is normally in a closed position.

8. The selective catalytic reduction(SCR) system (10) as claimed in claim 6, wherein the DCU (110) is configured to communicate with an indicating means on the dashboard of the vehicle in dependance of the quality information received from the quality sensor (104).