Claims:We claim:
1. A throttle body (100) for a vehicle, comprising:
an intake conduit (102);
a throttle valve (106) for said intake conduit (102) to control passage of air intake to at least one cylinder of an engine of said vehicle, and
an actuator (116) to control operation of said throttle valve (106),
characterized in that
a stop assembly (122) comprising a stop element (1222) supported by a spring (1224), so as to stop opening of said throttle valve (106) to two different positions.

2. The throttle body (100) as claimed in claim 1, wherein said spring (1224) moves said stop element (1222) against said actuator (116) to a limp-home position, when power supply to said actuator (116) is absent.

3. The throttle body (100) as claimed in claim 1, wherein said spring (1224) moves said stop element (1222) against said actuator (116) to a limp-home position, when an Engine Control Unit (ECU) operates said vehicle in a limp-home mode.

4. The throttle body (100) as claimed in claim 1, wherein said stop element (1222) is moved against said spring (1224) to an idle position by said actuator (116), said idle position provides minimum opening in said intake conduit (102).

5. The throttle body (100) as claimed in claim 1, wherein said throttle valve (106) is selected from a group comprising a rotating type valve and a sliding type valve.

6. The throttle body (100) as claimed in claim 1, wherein said actuator (116) is a stepper motor coupled to said throttle valve (106) through a throttle shaft (120).

7. The throttle body (100) as claimed in claim 1, wherein said actuator (116) is mechanically coupled to a coil spring (112).

, Description:Field of the invention:
[0001] The present invention relates to a throttle body and particular relates to a stop element to stop the throttle valve to specific positions.

Background of the invention:
[0002] According to a patent literature GB1357540, a throttle valve control mechanism for internal combustion engines is disclosed. The patent further discloses throttle stopper contains a plunger A which is loaded by a spring B into a position in which it holds the throttle valve slightly open during engine idling, the plunger being automatically withdrawn via a flexible cable C when the engine speed is above the idling speed, so as to allow complete closure of the throttle valve during engine over-run. For this purpose, the cable C may be operated by a solenoid or by a vacuum servo controlled by an electrically actuated valve, the engine speed being sensed by an electronic circuit responsive to the ignition impulse rate; a switch responsive to the alternator frequency; a relay connected in series with the battery charging circuit; or a switch operated by the engine vacuum.

Brief description of the accompanying drawings:
[0003] An embodiment of the disclosure is described with reference to the following accompanying drawing,
[0004] Fig. 1 illustrates a throttle body of a vehicle, according to an embodiment of the present invention, and
[0005] Fig. 2 illustrates a stop assembly of the throttle body, according to an embodiment of the present invention.

Detailed description of the embodiments:
[0006] Fig. 1 illustrates a throttle body of a vehicle, according to an embodiment of the present invention. The throttle body 100 comprises an intake conduit 102, a throttle valve 106 for the intake conduit 102 to control passage of air intake to at least one cylinder of an engine of the vehicle, and an actuator 116 to control operation of the throttle valve 106. The throttle body 100 is an electronic throttle body 100 where the throttle valve 106 is operated by the actuator. The throttle body 100 further comprises a stop assembly 122 comprising a stop element 1222 supported by a spring 1224 so as to stop opening of the throttle valve 106 to two different positions.
[0007] The throttle body 100 comprises the intake conduit 102. The intake conduit 102 is the throttle bore in case where the throttle body 100 is removable from an air intake system of the vehicle. A position sensor 104 is provided to detect the opening of the throttle valve 106. Alternatively, by monitoring the actuator 116, the position of the throttle valve 106 is detected by an Electronic Control Unit (ECU) of the vehicle. A throttle shaft 120 is coupled to the throttle valve 106. The throttle shaft 120 is operated by the actuator 116. A coil spring 112 is also coupled to the throttle shaft 120 through a spindle 110. The actuator 116 and the coil spring 112 are coupled to the throttle shaft 120 through gears 118 and 108, respectively. The actuator 116 is powered by a battery and controlled by the Electronic Control Unit (ECU). The electric connection is shown by the cables 114.
[0008] In accordance to an embodiment of the present invention, the actuator 116 is a stepper motor and the throttle shaft 120 is a lead screw. Alternatively, the actuator 116 is a mechanical assembly such as Bowden cable. In yet another alternative, the actuator 116 is a DC motor.
[0009] The cross-section of the intake conduit 102 or the throttle bore is rectangular, but the same must not be understood in limiting sense as other shaped cross-sections are equally applicable for different air-flow requirements. The air-flow is shown by the arrows.
[0010] Fig. 2 illustrates a stop assembly of the throttle body, according to an embodiment of the present invention. The throttle body 100 comprises the stop assembly 122, which either provided on a vehicle chassis or the intake conduit 102 itself. At least three positions of the throttle valve 106 is illustrated. At a first position 200 of the throttle valve 106, the spring 1224 moves the stop element 1222 against the actuator 116 to a limp-home position, when power to the actuator 116 is cut/absent. Alternatively, the spring 1224 moves the stop element 1222 during the failure of the actuator 116 or activation or operation of limp-home mode by the Engine Control Unit (ECU) of the vehicle. The limp-home mode corresponds to the limited functionality of the vehicle due to malfunction or fault in at least one important component of the vehicle. In the presence of limp-home mode, the vehicle needs to be driven at restricted conditions to nearby service station or house. The spring 1224 is designed to move the stop element 1222 against the resistance of the gearing 118 or 108 and the actuator 116. Thus, under current-less (no electric power) condition, the throttle valve 106 rests on the stop element 1222 providing opening for desired air flow to the engine. This ensures that the throttle valve 106 comes to a limp-home positon as a safety feature.
[0011] Further, the coil spring 112 does not overcome the force of the spring 1224. The coil spring 112 is designed to overcome the weight of throttle valve 106, the actuator 116, including the friction due to gearing 118, 108.
[0012] A second position 202 of the throttle valve 106 defines the idle position. When an ignition is switched ON and the engine is at idle, the actuator 116 overcomes the compression force of the spring 1224 and moves the throttle valve 106 to the idle position or the second position 202. The stop element 1222 is moved against the spring 1224 to the idle position by the actuator 116. The idle position provides required opening in the intake conduit 102 for idling of the engine.
[0013] A third position 204 of the throttle valve 106 defines the Wide Open Throttle (WOT) position. During the acceleration of the vehicle, the actuator 116 moves the throttle shaft 120 in the opposite direction to move the throttle valve 106 and provide more airflow cross-section. This repeats for each acceleration and deceleration of the vehicle.
[0014] In accordance to an embodiment of the present invention, the stop assembly 122 is provided for an electronic throttle body 100 with linear actuated throttle valve 106. The throttle body 100 is either provided with a fuel injector or is without the same. The throttle body 100 provides a simple construction with reduced cost. The construction is simple without any additional actuators and linkages, which also helps in the reducing the complexity with number of child parts hence the assembly line optimization. The geometrical tolerances are not critical for the components which are directly responsible for airflow control comprising a housing, the throttle shaft 120, throttle valve 106, gearings 108, 118 and the like. The throttle body 100 with linear throttle valve 106 is driven by electric-motor via a small lead-screw. The coil spring 112 acts as energy store for returning the throttle valve 106 in case of power cut-off and absorb operational vibration.
[0015] 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.