Claims:We claim:
1. An electronic throttle control system (100) in a vehicle comprising:
an ECU (109) powered by a power source (101), said ECU (109) electrically configured to a throttle position sensor (112) to receive a position of a throttle actuator of said vehicle; and
a throttle motor (105) controlled by said ECU (109) to receive a motor driving signal to actuate a throttle valve (107);
wherein said ECU (105) controls the supply of power to said throttle motor (105) from said power source (101) based on one or more predetermined condition.
2. The electronic throttle control system (100) as claimed in claim 1, wherein a first predetermined condition of said one or more predetermined condition is starting an engine (108) within a predetermined time.
3. The electronic throttle control system (100) as claimed in claim 1, wherein a second predetermined condition of said one or more predetermined condition is achieving a threshold voltage for electronic start stop switch (110).
4. The electronic throttle control system (100) as claimed in claim 1, wherein a third predetermined condition of said one or more predetermined condition is when said vehicle achieves a predetermined speed.
5. The electronic throttle control system (100) as claimed in claim 4, wherein said predetermined speed is measured using one or more vehicle speed sensor (111).
6. A method for actuating a throttle motor (105) in an electronic throttle control system (100) comprising the steps of:
switching ON an ignition key of a vehicle;
receiving a throttle input from a handle grip position sensor (112);
controlling a power to said throttle motor (105) based on one or more predetermined conditions; and
enabling said throttle motor (105) when an engine is ON.
7. The method for actuating a throttle motor (105) as claimed in claim 8, wherein a first condition of said one or more predetermined conditions is checking an engine ON condition for a predetermined time comprising the steps of:
disconnecting a battery from said throttle motor (105) if said engine (108) is OFF;
8. The method for actuating a throttle motor (105) as claimed in claim 8, wherein a second condition of said one or more predetermined conditions is checking a threshold voltage for an electronic start stop switch (105) comprising the steps of:
enabling throttle motor (105) when battery voltage is greater than a threshold voltage of said electronic start stop switch (110).
9. The method for actuating a throttle motor (105) as claimed in claim 8, wherein a third condition of said one or more predetermined conditions is checking a predetermined speed of said vehicle comprising the steps of:
monitoring said vehicle speed sensor (111) and one or more CAN lines;
checking for a malfunction in said vehicle speed sensor (111) and said one or more CAN lines;
enabling said throttle motor (105) when a malfunction detected in said vehicle speed sensor (111) or in said one or more CAN lines;
enabling a limp home mode when no malfunction detected in said vehicle speed sensor (111) and said one or more CAN lines; , Description:TECHNICAL FIELD
[0001] The present subject matter generally relates to a vehicle. The present subject matter specifically but not exclusively relates to an electronic throttle control system for a vehicle.
BACKGROUND
[0002] Generally, in motorcycle the grip on the handlebar can be rotated to control a throttle system of the motorcycle to control the air intake flow and thereby power and the torque output of the engine. The throttle valves are linked to the accelerator hand grip by a throttle cable located on a handle bar of a two or three wheeled vehicle.
[0003] Whereas an electronic throttle control system determines a target throttle valve position based on the accelerator position and various engine operating parameters and based on the control unit decision the position of the throttle valve is regulated electronically.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] The detailed description is described with reference to the accompanying figures. The same numbers are used throughout the drawings to reference like features and components.
[0005] Fig. 1 illustrates a flow diagram of the present subject matter involving an electronic throttle control system.
[0006] Fig. 2 illustrates a flow chart of the operation of the electronic throttle control system to check the engine ON condition for a predetermined time.
[0007] Fig. 3 illustrates an actuation of the throttle motor when the predetermined time to check the engine condition gets elapsed.
DETAILED DESCRIPTION
[0008] Unlike a mechanical throttle system, where the throttle valve is controlled by a throttle cable, the electronic throttle control system controls the opening and closing of the throttle valve electronically. The rider’s throttle position & input is determined by an ECU (Engine control unit) through a throttle opening sensor and based on the input received by the throttle opening sensor, the ECU makes a decision related to the throttle opening required for a throttle valve. An output signal from the ECU is sent to a DC motor to control the opening of the throttle valve. The DC motor is coupled to the throttle valve by a gear mechanism. Therefore, on the basis of the movement of the DC motor, the throttle valve opens and closes accordingly. The electronic control of the throttle system improves the response time and drivability over the mechanical throttle system.
[0009] The throttle valves are controlled electronically through a DC (Direct current) motor and any rider input in the throttle grip will enable the DC motor to actuate the throttle valve. It has been observed in many instances that the rider tends to turn the ignition key ON and do not actuate the electronic start switch (ESS). This behaviour tends to increase the delay time between the turning ON of the ignition key and the activation of ESS. Typically, during this condition, the battery continues to supply electric current to the throttle motor of the electronic throttle control device leading to undesirable drain of the battery.
[00010] Also in the case where the engine is in OFF condition but the battery of the vehicle is operating and the user of the vehicle rotates the handle bar throttle grip either intentionally or unintentionally then the battery supplies the required voltage to operate the DC motor to open or close the throttle valve and thereby causing draining of the battery. The draining of the battery leads to poor start ability of the vehicle as the battery State of Charge (SOC) can end up being low leading to SOC where at times SOC may not be sufficient to provide the required voltage to the components installed in the vehicle.
[00011] Hence, it is the object of the present subject matter to provide an electronic throttle control system to eliminate the problem associated with the draining of the battery when handle bar throttle grip input or throttle actuator input is provided to the ECU during the engine OFF condition. The present subject matter provides an electronic throttle based control system to control the throttle motor through ECU based on one or more predetermined conditions. First condition is based on the predetermined time for which the ECU checks for engine ON condition. Second condition is threshold voltage required for an electronic start stop switch in order to restart the throttle motor after the elapse of a predetermined time. Third condition is pre determined speed of the vehicle using a vehicle speed sensor when the electronic start stop switch starts malfunctioning.
[00012] Another aspect of the present subject matter is to provide an electronic throttle control system with a method to control a throttle motor on the basis of ON or OFF condition of the engine and the ECU receives a throttle input from the throttle position sensor configured to the handle bar of the vehicle. The said ECU checks the ON or OFF condition of the engine and if the engine is started within a predetermined time then the throttle motor gets enabled and if the engine fails to start then the battery gets disconnected and the power supply from the battery to the throttle motor gets disabled thereby preventing the wastage of the battery power.
[00013] Yet another aspect of the present subject matter is to provide an electronic throttle control system with an electronic start stop (ESS) switch. When the battery is disconnected from the throttle motor then electronic start stop switch enables the throttle motor.
[00014] Another aspect of the present subject matter is to provide a method to enable the throttle motor in the electronic throttle control system through a speed sensor, configured to detect the speed of the vehicle, when the battery voltage is below a threshold voltage and fails to enable the electronic start stop switch. In order to enable the throttle motor, the speed sensor detects the speed of the vehicle and if the speed is greater than a predetermined speed, then the ECU enables the throttle motor.
[00015] Yet another aspect of the present subject matter is to provide a method to monitor the speed sensor and CAN lines and to detect when the vehicle speed sensor, responsible for detecting the speed of the vehicle, fails to provide the speed input of the vehicle to the ECU. The ECU checks for any malfunction in the speed sensor or in a CAN line. If any malfunction is found in the speed sensor or any of the CAN line then the ECU enables the throttle motor and if no malfunction is found in the speed sensor or the CAN line and at the same time the throttle motor is not enabled then the vehicle’s limp home mode gets enabled. The above and other features, aspects and advantages of the subject matter will be better understood with regard to the following description, appended claims and accompanying drawings which are explained with reference to an embodiment of a two wheeled vehicle comprising an IC engine powertrain. However, in alternate embodiment, the powertrain can be an electric motor or a hybrid powertrain.
[00016] Fig. 1 illustrates the flow diagram of the present subject matter involving an electronic throttle control system (100). An ECU (109) powered by a power source such as a battery (101) is electrically configured to receive input from the electronic start stop switch (110) when the throttle motor (105) needs to be operated after switching ON the ignition of the vehicle in order to open a throttle valve (107) to provide air intake for combustion of fuel in the engine (108).The ECU (109) is also electrically configured to receive a speed input of the vehicle from a vehicle speed sensor (111) to determine whether the vehicle is in moving condition or not in order to actuate the throttle motor (105) to open the throttle valve when the battery (101) of the vehicle gets drained. ECU (109) is electrically configured to a handle grip or throttle position sensor (112) to receive a position of a handle grip or throttle actuator of the vehicle.
[00017] Further, in an additional embodiment, the ECU (109) provides one or more output to be displayed on the instrument cluster (113) based on various parameters of the engine (108). The instrument cluster (113) is connected to CAN (control area network) low lines. Similarly, in an additional embodiment, a tester (102) for testing the ECU (109) and an HECU (Hydraulic and Electronic control unit) (103), to prevent the rear wheels locking when braking, are connected to the ECU (109) through CAN low lines.
[00018] The vehicle speed sensor (111) can be a magnet based sensor such as a Hall Effect sensor which can detect the vehicle speed by detecting speed of the drive wheel and sends the information to the ECU (109). The ECU (109) is connected to the vehicle speed sensor (111) through a speed sensor cable (not shown). A handle grip or throttle actuator of the vehicle is provided with a handle grip position sensor (112). The handle grip of the vehicle is rotated by the user of the vehicle and handle grip position sensor (112) senses the change in the movement of the handle grip and the sensed movement of the handle grip is sent to the ECU (109) to indicate the required amount of opening to be enabled on the throttle (107) valve for intake of air into the intake system of the engine. A throttle motor (105) is configured to the ECU (109) to receive a motor driving signal to actuate the throttle vale (107). The throttle valve (107) is detachably attached to the engine (109) of an engine assembly of the vehicle to enable the air intake.
[00019] Fig.2 illustrates the flow chart of the operation of the electronic throttle control system (100) when the engine (108) condition is checked for a predetermined period. In step 201, the rider switches ON the ignition key and after the ignition key is switched ON the rider may give input for the opening of the throttle valve (107) by rotating the handlebar grip. In step 202, the handle grip position sensor (112) senses the rotation of the handle bar grip and receives the input from the rotation of the handlebar grip. The handle grip position sensor (112) is electrically connected to the ECU (Electric control unit) (109) powered by a power source such as a battery (101). The ECU (109) receives the throttle input from the handle grip position sensor (112). But before the ECU (109) enables the throttle motor (105) to open the throttle valve (107) for air intake, the ECU (109) , in step 203, checks whether the engine (108) is in ON condition or not. If the engine (108) is in ON condition then in step 204, the ECU (109) enables the throttle motor (105) and thereby throttle motor (105) actuates the throttle valve (107). But if the engine (108) is not in an ON condition then in step 205, the ECU (109) checks for a predetermined time (step 205) for the engine condition. And even if after the elapse of the predetermined time (set by e.g. the manufacturer and the predetermined time may be kept 8 to 10seconds) the engine (108) remains in an OFF condition then in step 207, the ECU (109) disconnects the battery (101) supply to the throttle motor (105) and prevents wastage of battery power. But if the user starts the ignition of the engine (108) within the predetermined time then the throttle motor (105) starts getting the power supply from the battery (101) and allows the throttle valve (107) to actuate as per the user’s requirement to allow air intake for combustion of the fuel in the engine (108). The predetermined time for checking the engine ON condition can be set by the manufacturer and ideally the predetermined time can be set in the range of 10 seconds to 12 seconds.
[00020] Fig.3 illustrates the actuation of the throttle motor (105) when the predetermined time to check the engine condition gets elapsed. After the elapse of the predetermined time for checking the engine ON condition if the user wants to start the ignition, a separate electronic start stop switch (110) is provided in the vehicle, which can be operated after the elapse of the predetermined time to start the throttle motor (105) by enabling the battery (101) supply to the throttle motor (105).
[00021] In step 301, the electronic start stop switch (110) is switched ON when the battery (101) gets disconnected. Generally, an electronic start stop switch (110) operates at certain voltage (~11volt) but if the state of charge of the battery (101) is not capable of providing voltage greater than 11 volt to the electronic start stop switch (110) then the throttle motor (105) does not start. Hence, after the electronic start stop switch (110) is switched ON by the user then, in step 302, the ECU (109) checks whether the battery voltage is greater than the voltage required to enable the electronic start stop switch (110). If the battery voltage is greater than the voltage required to operate the electronic start stop switch (110) then in step 303, the electronic start stop switch (110) is switched ON in order to enable the throttle motor (105) to actuate the throttle valve (107).
[00022] But if the battery voltage is below the required voltage to operate the electronic start stop switch (110) then the user of the vehicle has to push the vehicle to achieve a minimum vehicle speed. A vehicle speed sensor (111) detects the speed of the drive wheel and sends the speed input to the ECU (109) through a speed sensor cable (not shown). The ECU (109) checks for the speed of the vehicle in step 304 and compares the speed of the vehicle with the predetermined speed. When the vehicle is set in motion to achieve the predetermined speed then the ECU (109) monitors the vehicle speed sensor (111) and the CAN lines in step 305. Then, in step 306, ECU (109) checks if there is any malfunction in the vehicle speed sensor (111) or in any of the CAN lines or not.
[00023] When ECU (109) detects any malfunction in either of the vehicle speed sensor (111) or in the CAN line then in step 307, the ECU (109) enables the actuation of throttle motor (105). But if the ECU (109) does not detect any malfunction then in step (308), the ECU (109) further checks for the throttle motor (105) and if the throttle motor (105) does not get enabled despite of not detecting any malfunction in the vehicle speed sensor (111) or any of the CAN line then in step 309, the ECU (109) enables limp home mode and an indicator corresponding to the limp home mode in the instrument cluster (113) gets switched ON and starts indicating it to the user about any malfunction in the throttle motor (105). Further, if no malfunction is detected and the throttle motor gets enabled then no further action is taken by the ECU (109).