CLIAMS:We Claim:
1 An exhaust path (105) in which a catalytic converter (110) is disposed in said exhaust path (105);
characterized in that
a bypass path (115) comprising an inlet and an outlet, said bypass path (115) branching off from said exhaust path (105) and merging again with said exhaust path (105) upstream of said catalytic converter (110);
a flap (120) located at said inlet of said bypass path (115), wherein said flap (120) adapted to operate between a closed position and an open position;
a voltage varying element (125), at least a part of said flap (120) in electrical contact with said voltage varying element (125); and
a heating element (130) located upstream of said inlet of said bypass path (115) and in electrical contact with said voltage varying element (125).

2 The exhaust path (105) as claimed in claim 1, wherein said flap (120) is made of a bi-metallic material.

3 The exhaust path (105) as claimed in claim 1, wherein said electrical contact between said voltage varying element (125) and said flap (120) is established through a connector (145) that is configured to deflect along surface of said voltage varying element (125).

4 The exhaust path (105) as claimed in claim 1, wherein said closed position corresponds to closure of said inlet of said bypass path (115) and said open position corresponds to opening of said inlet of said bypass path (115).

5 The exhaust path (105) as claimed in claim 1, wherein said voltage varying element (125) is at least one selected from a group of voltage varying elements such as a potentiometer, a rheostat and a voltage divider. ,TagSPECI:FIELD OF THE INVENTION
[001] This invention relates to an exhaust path in which a catalytic converter is disposed downstream of said exhaust path.

BACKGROUND OF THE INVENTION
[002] A catalytic converter is a component required for treatment of exhaust gas. For optimal functioning of the catalytic converter, temperature of the exhaust gas is required to be maintained within a defined range. Temperature of the exhaust gas being above a maximum temperature, with respect to the defined range, causes damage to the catalytic converter. Also, the temperature of the exhaust gas being below a minimum temperature, with respect to the defined range, causes the catalytic converter to be non-functional as the catalytic converter does not light off and hence untreated exhaust gas is emitted into the atmosphere.

[003] When the temperature of the exhaust gas is above the maximum temperature, a technique to cool the exhaust gas, such that the temperature, of the exhaust gas, is maintained within the defined range, is required. If the temperature of the exhaust gas is below the minimum temperature then a technique to heat the exhaust gas such that the catalytic converter lights off is required.

[004] An US patent number US6951099 discloses one such method of heating the exhaust gas and an US application number US 2010/0000205 discloses a method of cooling the exhaust gas.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
[005] Figure 1 illustrates flow of exhaust gas along an exhaust path in accordance with an embodiment; and

[006] Figure 2 illustrates flow of exhaust gas along a bypass path in accordance with an embodiment.

DETAILED DESCRIPTION
[007] Figure 1 illustrates flow of exhaust gas along an exhaust path in accordance with an embodiment.

[008] In accordance with this disclosure, an exhaust path 105 in which a catalytic converter 110 is disposed in the exhaust path 105 is characterized by a bypass path 115. The bypass path 115 comprises an inlet and an outlet. The bypass path 115 branches off from the exhaust path 105 and merges again with the exhaust path 105 upstream of the catalytic converter 110. The exhaust path 105 is also characterized by a flap 120 located at the inlet of the bypass path 115. The flap 120 is adapted to operate between a closed position and an open position. The exhaust path 105 is further characterized by a voltage varying element 125. At least a part of the flap 120 is in electrical contact with the voltage varying element 125. Further the exhaust path 105 is characterized by a heating element 130 located upstream of the inlet of the bypass path 115 and is in electrical contact with the voltage varying element 125.

[009] The bypass path 115 may be made of materials such as aluminium, ceramic, CI and alloys of steel. Surface area of the bypass path 115 is proportional to difference between maximum temperature and the minimum temperature with respect to a defined temperature range over which the catalytic converter 110 functions optimally.

[0010] The flap 120 is located at the inlet of the bypass path 115. In one example, the flap 120 may be made of a bi-metallic material. The flap can also be made of various other materials similar to the bi-metallic material. One end of the flap 120 is fixed to the bypass path 115 and another end is pivotally connected to the connector 145 so that the movement of the flap 120 is imparted to the connector 145. The flap 120 is adapted to operate between the closed position and the open position thereby closing and opening the bypass path 115 based on the temperature of the exhaust gas.

[0011] The electrical contact between the voltage varying element 125 and the flap is established through the connector 145. The connector 145 is adapted to deflect along surface of the voltage varying element 125 based on movement of the flap 120. Position of the connector 145 on the surface of the voltage varying element 125 corresponds to a current value that is supplied to the heating element 130. Therefore, as the position of the connector 145, on the voltage varying element 125 varies, the current value, supplied to the heating element 130, varies correspondingly.

[0012] One end of the heating element 130 is in electrical contact with the voltage varying element 125. Another end of the heating element 130 is connected to the power source 140. Hence, the heating element 130 and the voltage varying element 125 are in series connection with the power source 140.

[0013] The voltage varying element 125 is at least one selected from a group of voltage varying elements such as a potentiometer, a rheostat and a voltage divider. One end of the voltage varying element 125 is in electrical contact with the flap 120 through the connector 145. Another end of the voltage varying element 125 is connected to a power source 140 so that the voltage varying element 125 supplies current, to the heating element 130, based on the position of the connector 145 on the surface of the voltage varying element 125.

[0014] The catalytic converter 110 aids in treatment of the exhaust gas only if temperature of the exhaust gas is within the defined temperature range. In one case, the temperature of the exhaust gas may be lesser than the minimum temperature with respect to the defined temperature range.

[0015] In such cases, the flap is adapted to position itself in a closed position as shown in Figure 1. The closed position, of the flap, corresponds to closure of the inlet of the bypass path 115 so that the exhaust gas is allowed to flow only along the exhaust path 105. When the flap is in the closed position, the position of the connector, on the voltage varying element 125, is such that the voltage varying element 125 outputs a current equal to the power source. This current is supplied to the heating element 130 for heating the exhaust gas.

[0016] The heating element 130 is adapted to heat the exhaust gas such that the temperature of the exhaust gas reaches a temperature equal to a light off temperature of the catalytic converter 110. Hence, heating of the exhaust gas enables the catalytic converter 110 to light off and thereby aid in the treatment of the exhaust gas.

[0017] In another case, the temperature of the exhaust gas may be higher than the maximum temperature with respect to the defined temperature range. When the exhaust gas of such a temperature strikes the flap 120, the shape of the flap 120 is deformed. Deformation of the flap 120 causes opening of the inlet of the bypass path 115 and blockage of the exhaust path 105 as shown in Figure 2. As a result, the exhaust gas flows through the bypass path 115.

[0018] Flow of the exhaust gas along the bypass path 115 enables reduction of the temperature of the exhaust gas since the exhaust gas travels a larger distance that corresponds to the surface area of the bypass path 115. The reduction is such that the exhaust gas temperature falls within the defined temperature range.

[0019] Also, the deformation of the flap 120 moves the connector 145 such that the connector 145 undergoes deflection along the surface of the voltage varying element 125. The position of the connector 145 due to deflection is such that the current supplied to the heating element 130 is zero. Hence, heating of the exhaust gas does not occur.

[0020] In yet another case, the temperature of the exhaust gas deforms the flap 120 such that the inlet of the bypass path 115 is partially open. In such cases the exhaust gas flows through both the exhaust path 105 and the bypass path 115.

[0021] Such deformation of the flap 120 causes deflection of the connector 145 along the surface of the voltage varying element 125. The position of the connector 145, due to the deflection, corresponds to a current that is supplied to the heating element 130. Based on the current that is supplied to the heating element 130, the exhaust gas is heated to a temperature that falls within the defined temperature range.

[0022] Hence by operating the flap based on the temperature of the exhaust gas optimal functioning of the catalytic converter 110 is ensured.

[0023] It must be understood that the embodiments explained above are only illustrative and do not limit the scope of the disclosure. Many modifications in the embodiments with regard to the voltage varying element 125, heating element 130, material and shape of the flap 120, material and shape of the bypass path 115 are envisaged and form a part of this invention. The scope of the invention is only limited by the claims.