Claims:

1. An idle engine shut down system (100) for a vehicle comprises:
plurality of vehicle sensors viz;
a clutch pedal sensor (10),
a brake pedal sensor (20),
a accelerator pedal sensor (30),
a vehicle speed sensor (40),
a gear position sensor (50),
a battery state detecting sensor (60) and
an ECU (80) configured to receive signals, process and calculate engine torque for detecting working state of air conditioner for controlling the idle engine shutdown of a vehicle.

2. The idle engine shut down system (100) for vehicle as claimed in claim 1, wherein the said clutch pedal sensor (10) is a clutch switch configured to be mounted on clutch pedal to determine clutch pedal position and send signal to ECU (80).

3. The idle engine shut down system (100) for vehicle as claimed in claim 1, wherein the said brake pedal sensor (20) is a brake switch configured to be mounted on brake pedal to determine brake pedal position and send signal to ECU (80).

4. The idle engine shut down system (100) for vehicle as claimed in claim 1, wherein the said accelerator pedal sensor (30) is an accelerator switch configured to be mounted on accelerator pedal to determine accelerator pedal position and send signal to ECU (80).

5. The idle engine shut down system (100) for vehicle as claimed in claim 1, wherein the said gear position sensor (50) is configured for detecting gear positions and sending signals to ECU (80).

6. The idle engine shut down system (100) for vehicle as claimed in claim 1, wherein the said ECU (80) is configured for calculating engine torque value and determining working state of air conditioner compressor (70).

7. The idle engine shut down system (100) for vehicle as claimed in claim 1, wherein the said ECU (80) is configured to shut down the engine based on detection of clutch pedal in depressed position, detection of brake pedal in depressed position, detection of accelerator pedal in released position, speed of vehicle to be zero, gear in neutral position, state of charge of battery above predetermined value and engine torque value less than predetermined value.

8. The idle engine shut down system (100) for vehicle as claimed in claim 1, wherein the idle engine shut down system (100) is configured to save fuel and increase fuel efficiency of vehicle.
, Description:FORM 2

THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENT RULES, 2003

COMPLETE SPECIFICATION
(See Section 10 and Rule 13)

Title of invention:
SYSTEM FOR IDLE SHUTDOWN OF VEHICLE ENGINE

Applicant:
Tata Motors Limited
A company Incorporated in India under the Companies Act, 1956
Having address:
Bombay House, 24 Homi Mody Street,
Hutatma Chowk, Mumbai 400001,
Maharashtra, India

The following specification particularly describes the subject matter and the manner in which it is to be performed.

TECHNICAL FIELD
[001] The present subject matter described herein, in general, relates to idle shutdown of vehicle. More particularly, the subject matter relates to idle shutdown of vehicle by ECU based on inputs from multiple sensors to improve fuel economy.
BACKGROUND
[002] In current scenario cost of fuel are rising and optimum use of fuel to improve the fuel economy is required. Many times people keep the vehicle engine running when the vehicle is idle or stationary; this leads to increase in fuel consumption. Idle shutdown is to stop working of an engine during a stop of a vehicle, in order to reduce fuel consumption and gas emission during the stop of the vehicle. It is preferable to perform idle shutdown when the automobile stops for a relatively long time, for example, when the automobile stops at a traffic light.
[003] The vehicles offered by manufacturers are available in non-air conditioner and air conditioner model. The hardware configuration and engine calibration remains same for both non-air conditioner and air conditioner model. Customer buying a Non AC vehicle and later on converting the vehicle into AC model in this case the existing idle shut down technology does not detect the AC compressor condition. This may lead to vehicle shut down during AC ON running condition and it will create discomfort to vehicle occupants. In order to solve this problem, varieties of techniques have been associated for prediction of engine shutdown in idle condition. Accessory load such as air conditioner or alternator or compressor also causes heavy loss in engine efficiency, so a system has to be developed for idle shutdown of an engine after considering various vehicle parameters.
OBJECTS OF THE INVENTION
[004] Main object of the present invention is to idle shutdown the vehicle engine to improve fuel economy of vehicle.
[005] Another object of the invention is to determine AC compressor ON/OFF based on engine torque value to ECU.
[006] Yet another object of the invention is to idle shutdown the vehicle engine based on working state of AC compressor.
[007] Yet another object of invention is to idle shutdown the vehicle engine by ECU based on inputs from vehicle clutch pedal, accelerator pedal, brake pedal, speed, battery charge state, gear in neutral position and AC compressor OFF.
SUMMARY
[008] Before the present systems and methods, are described, it is to be understood that this application is not limited to the particular systems, and methodologies described, as there can be multiple possible embodiments which are not expressly illustrated in the present disclosure. It is also to be understood that the terminology used in the description is for the purpose of describing the particular versions or embodiments only and is not intended to limit the scope of the present application. This summary is provided to introduce concepts related to idle shut down of vehicle engine to improve fuel economy, which is further described below in the detailed description. This summary is not intended to identify essential features of the claimed subject matter nor is it intended for use in determining or limiting the scope of the claimed subject matter.
[009] In one implementation, an idle vehicle shut down system to monitor multiple idle shutdown vehicle parameters and control the vehicle engine shutdown by engine control unit. The idle vehicle shut down parameters include detection of vehicle clutch pedal depression, brake depression, accelerator pedal not depressed, vehicle speed is zero, gear position in neutral, battery charge state greater than predetermined value and air conditioner compressor OFF to shut down the vehicle engine by ECU. The idle vehicle shut down system improves vehicle fuel economy. Air conditioner compressor ON/OFF condition is determined by value of engine torque calculated by ECU. The monitoring of air conditioner ON/OFF for shut down of vehicle engine reduces the discomfort to vehicle occupants.
STATEMENT OF INVENTION
[0010] Accordingly, the present invention discloses an idle engine shut down system for a vehicle comprising of plurality of vehicle sensors viz; clutch pedal sensor, a brake pedal sensor, an accelerator pedal sensor, a vehicle speed sensor, a gear position sensor, a battery state detecting sensor and an ECU configured to receive signals, process and calculate engine torque for detecting working state of air conditioner for controlling the idle engine shutdown of a vehicle.
[0011] Accordingly, the present invention discloses the clutch pedal sensor is a clutch switch configured to be mounted on clutch pedal to determine clutch pedal position and send signal to ECU. The brake pedal sensor is a brake switch configured to be mounted on brake pedal to determine brake pedal position and send signal to ECU. The accelerator pedal sensor is an accelerator switch configured to be mounted on accelerator pedal to determine accelerator pedal position and send signal to ECU. The gear position sensor is configured for detecting gear position and sending signal to ECU. The ECU is configured for calculating engine torque value and determining working state of air conditioner compressor. The ECU is configured to shut down the engine based on detection of clutch pedal in depressed position, detection of brake pedal in depressed position, detection of accelerator pedal in released position, speed of vehicle to be zero, gear in neutral position, detecting state of charge of battery above predetermined value and engine torque value less than predetermined value. The idle engine shut down system is configured to save fuel and increase fuel efficiency of vehicle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The foregoing summary, as well as the following detailed description of embodiment, is better understood when read in conjunction with the appended drawing. For the purpose of illustrating the disclosure, there is shown in the present document example constructions of the disclosure, however, the disclosure is not limited to the specific methods and apparatus disclosed in the document and the drawing.
[0013] The detailed description is described with reference to the accompanying figure. In the figure, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the drawing to refer like features and components.
[0014] Figure 1 illustrates a circuit diagram of idle engine shut down system for vehicle.
[0015] Figure depicts various embodiments of the present disclosure for purpose of illustration only. Only skilled in the art will readily recognize from the following discussion that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
DETAILED DESCRIPTION
[0016] Some embodiments of this disclosure, illustrating all its features, will now be discussed in detail. The words “comprising”, “having”, and “including,” and other forms thereof, are intended to be equivalent in meaning and be open ended in that an item or items following any one of these words is not meant to be an exhaustive listing of such item or items, or meant to be limited to only the listed item or items. Although any systems and methods similar or equivalent to those described herein can be used in the practice or testing of embodiments of the present disclosure, the exemplary, systems and methods are now described. The disclosed embodiments are merely exemplary of the disclosure, which may be embodied in various forms.
[0017] Various modification to the embodiment will be readily apparent to those skilled in the art and the generic principles herein may be applied to another embodiment. However, one of ordinary skill in the art will readily recognize that the present disclosure is not intended to be limited to the embodiments illustrated but is to be accorded the widest scope consistent with the principles and features described herein.
[0018] The present invention discloses an idle shutdown system for vehicle. The idle shut down system is adapted for monitoring different operating conditions vehicle to determine that the vehicle is stationary. The vehicle conditions like clutch pedal position, brake pedal position, accelerator pedal position, the gear engagement, vehicle speed zero, state of charge of battery and checking the working condition of air conditioner compressor. The air conditioner compressor ON/OFF input to ECU is determined by engine torque or load. Various switches or sensors are configured to determine the state of different parameters of vehicle and send signal to ECU for controlling the idle shut down of vehicle. ECU shuts down the engine based on the signals received from various sensors like clutch pedal depression sensor, brake pedal depression sensor, accelerator pedal depression sensor, vehicle speed sensor, gear position sensor, battery state of charge sensor and air conditioner compressor ON/OFF detected by ECU based on engine torque value.
[0019] Now Figure 1 illustrates a circuit diagram of idle engine shut down system (100) for vehicle. The idle engine shutdown system includes a clutch pedal sensor (10), brake pedal sensor (20), accelerator pedal sensor (30), vehicle speed sensor (40), gear position sensor (50), battery state detecting sensor (60), air conditioner compressor (70) and ECU (80). The above parameters play an important role in shutting down the engine to save fuel and improve fuel economy.
[0020] Further, referring to figure 1 the ECU (80) is configured to receive inputs from clutch switch, brake switch, accelerator switch, speed sensor, gear position sensor, battery state sensor and air conditioner compressor ON/OFF. The switch or sensor configured on clutch pedal (10) signals the ECU (80) of the current position of clutch pedal like whether the clutch pedal is released or in depressed condition. The switch or sensor configured on brake pedal (20) signals the ECU (80) of the actual position of brake pedal like whether the brake pedal is released or in depressed condition. The switch or sensor configured on accelerator pedal (30) signals the ECU (80) of accelerator pedal in released or in depressed condition. A vehicle speed sensor (40) is configured to monitor vehicle speed and signal the vehicle speed to ECU (80). A gear position sensor (50) is configured to monitor gear positions and send signal to ECU (80) of gear position. A battery state detecting sensor (60) is configured to detect the available battery percentage and signal the available battery value to ECU (80). However, the occupants of the vehicle must have kept the vehicle in idle condition for use of air conditioner. Hence only based on above parameters ECU should not ideally shut down the vehicle after satisfying the aforesaid parameters related to idle running of engine. One of the crucial parameter for idle engine shutdown to be considered is working state of the compressor of air conditioner. Hence, as per one embodiment of this invention the idle engine shutdown will occur only after checking the working state of AC compressor. The ECU (80) is configured for calculating engine torque value and determining working state of air conditioner compressor (70) based on engine torque value. The engine torque value in air conditioner ON state will always be higher than air conditioner OFF state. The vehicle idle condition is determined based on clutch pedal depressed, brake pedal depressed, accelerator pedal not depressed, vehicle speed is equal to zero, gear in neutral position, battery charge is greater than 70% and AC compressor OFF based on engine torque value. On detecting the vehicle, idle condition the ECU (80) shuts down the engine to improve fuel economy.
[0021] According to one embodiment of invention the idle engine shutdown system can be installed on vehicles manufactured by OEM’s and vehicles retrofitted with air conditioners.
[0022] Accordingly, the present invention discloses an idle engine shut down system (100) for a vehicle comprises: plurality of vehicle sensors viz clutch pedal sensor (10) a brake pedal sensor (20) a accelerator pedal sensor (30) a vehicle speed sensor (40), a gear position sensor (50), a battery state detecting sensor (60) and an ECU (80) configured to receive signals, process and calculate engine torque for detecting working state of air conditioner for controlling the idle engine shutdown of a vehicle. The clutch pedal sensor (10) is a clutch switch configured to be mounted on clutch pedal to determine clutch pedal position and send signal to ECU (80). The brake pedal sensor (20) is a brake switch configured to be mounted on brake pedal to determine brake pedal position and send signal to ECU (80). The accelerator pedal sensor (30) is an accelerator switch configured to be mounted on accelerator pedal to determine accelerator pedal position and send signal to ECU (80). The gear position sensor (50) is configured for detecting the gear position and sending signal to ECU (80). The ECU (80) is configured for calculating engine torque value and determining working state of air conditioner compressor (70). The ECU (80) is configured to shut down the engine based on detection of clutch pedal in depressed position, detection of brake pedal in depressed position, detection of accelerator pedal in released position, speed of vehicle to be zero, gear in neutral position, detecting state of charge of battery above predetermined value and engine torque value less than predetermined value. The idle engine shut down system (100) is configured to save fuel and improve fuel efficiency of vehicle.
[0023] Exemplary embodiments discussed above may provide certain advantages. Though not required to practice aspects of the disclosure, these advantages may include those provided by the following features.
[0024] Some embodiments provide an idle shut down system for vehicle.
[0025] Some embodiments improve fuel economy of vehicle.
[0026] Although implementations for an idle engine shut down system for vehicle to improve fuel economy have been described in language specific to structural features and/or methods, it is to be understood that the appended claims are not necessarily limited to the specific features or methods described.
[0027] Figure 1 is now described using the reference numbers stated in the below table.
[0028] REFERRAL NUMERALS:
Element Description Reference Numeral
Clutch pedal sensor 10
Brake pedal sensor 20
Accelerator pedal sensor 30
Speed sensor 40
Gear Position sensor 50
Battery state detecting sensor 60
AC compressor 70
ECU 80
Idle shut down system 100