Claims:We Claim:
1. A supercharger (100), said supercharger (100) adapted to be located upstream to an engine (102), and comprising at least:
an inlet path (104), an outlet path (106), and a bypass path (108) comprising a control valve (110); characterized in that:
at least one sensor (112) located in said outlet path (106), said at least one sensor (112) in communication with a control unit (114), said control unit (114) adapted to control said control valve (110) for regulating air flow through any one of the inlet path (104) and said bypass path (108), based upon output of said at least one sensor (112).
2. The supercharger (100) of claim 1, wherein said at least one sensor (112) is a boost pressure sensor.
3. The supercharger (100) of claim 2, wherein said boost pressure sensor is integrated with said outlet path (106) of said supercharger (100).
4. A method for controlling flow of air in a supercharger 100, said supercharger 100 adapted to be located upstream to an engine 102, and comprising at least:
an inlet path 104, at least one sensor (112) located in an outlet path 106, and a bypass path 108 comprising a control valve 110, said method comprising:
receiving (200), by a control unit (114) the pressure of air at said outlet path 106 from said sensor (112);
determining (202), by said control unit (114), the pressure of air required in said engine 102; and
operating (204) said control valve 110 to regulate flow of air in dependence of the pressure of air required in said engine 102.
, Description:Field of the invention
[0001] This invention relates to a supercharger.

Background of the invention
[0002] Emission regulation for single cylinder engine, poses a challenge, especially in light of Bharat stage VI regulations. Main disadvantage of single cylinder naturally aspirated engine is the high sensitivity to smoke emission especially in full load and the lack of power and torque. One of the methods for increasing power developed by the engine is through the use of a supercharger. A few superchargers have a switchable bypass flap, in order not to permanently pressurize the inlet air when the engine doesn’t need it and to avoid therefore an unnecessary loss in engine power. The bypass of the charger is usually done by an electrically controlled bypass valve/ control valve.
[0003] Due to production variations in parts of supercharger, the boost pressure of air in supercharger changes. Hence, there is a need for accurate control of bypass flap by taking the actual boost pressure of the supercharger in consideration.
[0004] Prior art patent application US4891946 discloses an apparatus for control of operational characteristics of supercharger in an internal combustion engine. The apparatus is provided for controlling the operational characteristics of a supercharger in an internal combustion engine with the supercharger, including a compressor. The apparatus comprises a pressure sensor positioned in an intake passage downstream of the compressor for detecting the pressure of the compressor at a revolution sensor operatively coupled to the engine for detecting the revolution speed of the engine. An arithmetic means has its inputs coupled to the pressure sensor and revolution sensor and arithmetically operates on the output signals of the pressure sensor and revolution sensor in accordance with predetermined control characteristics for providing an output signal in accordance therewith. A control means is coupled to the output of the arithmetic means for controlling the pressure of the compressor in accordance with the output signal of the arithmetic means, and changing means are provided for manually changing the predetermined control characteristics of the arithmetic means.

Brief description of the accompanying drawing
[0005] Different modes of the invention are disclosed in detail in the description and illustrated in the accompanying drawing:

[0006] FIG. 1a illustrates a supercharger;
[0007] FIG. 1b illustrates working of the supercharger; and
[0008] FIG. 2 illustrates a method for controlling flow of air in a supercharger.

Detailed description of the embodiments
[0009] FIG. 1 illustrates a supercharger 100. The supercharger 100 is adapted to be located upstream to an engine 102, and comprises at least an inlet path 104, an outlet path, and a bypass path 108 comprising a control valve 110. At least one sensor is located in the outlet path 106, and is in communication with a control unit 114, the control unit 114 adapted to control the control valve 110 for regulating air flow through any one of the inlet path 104 and said bypass path 108, based upon output of at least one sensor 112. In an embodiment, the sensor may be a boost pressure sensor. The boost pressure sensor is integrated with said outlet path 106 of said supercharger 100.
[0010] FIG. 1b illustrates working of the supercharger. The supercharger 100 is mechanically driven by the engine 102 through a pulley mechanism. The supercharger 100 comprises a control valve 110 also called as a bypass flap which is electrically actuated by the control unit 114 to do supercharging only when requested. Whenever supercharging is required the control valve 110 will close the bypass path 108, and air from atmosphere will flow through the inlet path 104 of the supercharger 100 and into the engine 102. When the power that is to be produced from the engine 102 is such that, supercharging is not required, the control unit 114 will operate the control valve 110 to close the inlet path 104 of the supercharger 100. Hence the air will now flow only through the bypass path 108.
[0011] FIG. 2 illustrates a method for controlling flow of air in a supercharger 100. The supercharger 100 is adapted to be located upstream to an engine 102 and comprises an inlet path 104, an outlet path 106, at least one sensor located in the outlet path 106, and a bypass path 108 comprising a control valve 110. The method comprises, receiving 200, by a control unit (114) the pressure of air at the outlet path 106 from a sensor. The control unit also determines 202, the pressure of air required in the engine 102. The control valve 110 is operated 204 to regulate flow of air in dependence of the pressure of air required in the engine 102.
[0012] In the proposed method, the control unit 114 uses the boost pressure value detected by the sensor that is located at the outlet path 106 as an input. The control unit 114 determines the pressure of air that needs to the supplied to the engine based on engine operational information and engine characteristics. In case the demand from the engine is less, the control unit 114 operates the control valve 110 to close the inlet path 104. Therefore, air passes through the bypass path 108. In case the demand from the engine is more, the control unit 114 operates the control valve 110 to close the bypass 108 so that air flows through the supercharger 100. The proposed method enables a very accurate defining of the opening and/ or closing of the control valve 110. Also, it is possible to define with the proposed design the control valve switchings points for various pressure values.
[0013] It should be understood that embodiments explained in the description above are only illustrative and do not limit the scope of this invention in terms of type of supercharger. 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.