Claims:1. A method for controlling the hydraulic system of a vehicle to control stalling of an engine comprising :
? At least one sensing unit 1 is mounted on an alternator of the engine to measures real time engine speed and further transfers it to the micro-controller unit;
? At least one sensing unit 2 is disposed on the travel pump to estimate real time travel pump pressure ;
? At least one sensing unit 3 is disposed on the vibration pump to estimate the real time vibration pump pressure;
? At least one micro-controller unit to receive input values from the sensing units;
? At least one audio or visual or both types of indications to trigger an operator; and
? At least one joystick or lever to regulate the travel pump pressure, the vibration pump pressure and the engine speed.

2. A method for controlling the hydraulic system of a vehicle to control stalling of an engine claimed in claim 1 wherein, the micro-controller unit receives real time inputs from the sensing unit 1, the sensing unit 2 and the sensing unit 3.
3. A method for controlling the hydraulic system of a vehicle to control stalling of an engine claimed in claim 1 wherein, certain pre-determined threshold values against the sensing unit 1, the sensing unit 2 and the sensing unit 3 are recorded into the micro-controller unit.

4. A method for controlling the hydraulic system of a vehicle to control stalling of an engine claimed in claim 1 wherein, the input values received from the sensing unit 1 is less than the pre-determined threshold values against the sensing unit 1 recorded into the micro-controller unit then the audio or visual or both type of indications activated on the dashboard placed proximity to the operator.

5. A method for controlling the hydraulic system of a vehicle to control stalling of an engine claimed in claim 1 wherein, the input values received from the sensing unit 2 or the sensing unit 3 are more than the pre-determined threshold values against the corresponding sensing unit recorded into the micro-controller unit then the audio or visual or both type of indications activated against the corresponding sensing unit interface placed on the dashboard located proximity to the operator.

6. A method for controlling the hydraulic system of a vehicle to control stalling of an engine claimed in claim 1 wherein, the operator ignores or does not manipulate the joystick or the lever to regulate the travel pump pressure, the vibration pump pressure and the engine speed within a pre-determined time then the micro-controller unit self-regulate or adjust the value against either of the travel pump pressure, the vibration pump pressure and the engine speed or all against which the audio or visual or both types of indications activated on the dashboard.

7. A method for controlling the hydraulic system of a vehicle to control stalling of an engine claimed in claim 1 wherein,
? the threshold values against the sensing unit 1 is recorded in between 1000-1600 RPM the micro-controller unit;
? the threshold values against the sensing unit 2 is recorded in between 200 - 500 bar the micro-controller unit; and
? the threshold values against the sensing unit 3 is recorded in between 100- 300 bar in the micro-controller unit.

8. A method for controlling the hydraulic system of a vehicle to control stalling of an engine claimed in claim 7 wherein,
? the input values received from the sensing unit 1 is less than 1000-1600 RPM;
? the input values received from the sensing unit 2 is more than 200 - 500 bar ; and
? the input values received from the sensing unit 2 is more than 100- 300 bar;
then the audio or visual or both type of indications activated on the dashboard placed proximity to the operator.

9. A method for controlling the hydraulic system of a vehicle to control stalling of an engine claimed in claim 8 wherein, the operator ignores or does not manipulate the joystick or the lever to regulate the travel pump pressure, the vibration pump pressure and the engine speed within a pre-determined time then the micro-controller unit self-regulate or adjust the input value against either of the travel pump pressure by de-stroking the travel pump against which the audio or visual or both types of indications activated on the dashboard.
, Description:FIELD OF THE INVENTION
The present invention relates to an off-road vehicle, earthmoving vehicle and particularly a method for controlling an engine stall for the off-road vehicle, construction, earthmoving vehicle such as tractor, wheel loader, excavator, compaction machine etc. and more particularly to controlling a hydraulic system in order to control stalling of the engine.

BACKGROUND OF THE INVENTION
Due to the huge size and weight of the off-road or construction machine and functions need to perform while in the field and hence these off-road or construction machine generally well equipped with hydraulics system to control various operations of machine such as digging, excavating, loading, hammering, compaction etc. as well to provide power to various auxiliary or additional equipment used in such machine.
The hydraulic system further utilized in earthmoving or construction machine to convenience to operator to control various functions and also to provide better safety to operator and people working around the machine.

The typical earthmoving or construction equipment includes hydraulic system having one or more hydraulic pump. Various hydraulically operated services are linked with the hydraulic pump. One or more pressure relief valve or control valves are used to control supply of hydraulic fluid from the hydraulic pump to fluid pressure lines used for various operations. These pressure relief valve or control valves are controlled by operator via joystick or dashboard or any other actuating means. Thus machine operation may use control interface to control operation of the one or more control valves to cause actuation of one or more of the actuators. The actuators are used for controlling various operation and parts of machine.
The hydraulic pump is used for circulating pressurised hydraulic fluid across various fluid circulation lines to perform various mentioned operations. The standard corresponding fluid pressure is required throughout these lines to perform such operations. However, if there has been least little pressure drop across the pressure line causes operation may stop or stall. There may possibility that the hydraulic pump become disabled or is not operating.
Conventionally the earthmoving or construction machine equipped with above mentioned hydraulic system. However, pressure of hydraulic fluid is controlled by operator through joystick or any other manual means. It is often observed that a machine operator has to perform two or more tasks simultaneously while working on a machine. A machine operator has always needs to control the pressure of one or more hydraulic pumps at a real time. Whenever the hydraulic pump get stalled, disabled or not operating because of overloading or lack of hydraulic fluid in pressure line, machine operator has to regulate control valve or relief valve through joystick or any other manual means.
In order to overcome the stalling effect due to the hydraulic pump system is disabled or not operating because of overloading, it is more desirable to have a method for controlling an engine stall which is simple in construction, effective and cost effective than previously known methods and solves or at least relieves some of the problems discussed above.
It is therefore an object of the present invention is to overcome one or more problems associated with the prior art.
Another object of the present invention is to develop simple and effective have the method for controlling an engine stall.
Yet another object of the present invention is to the method for controlling an engine stall which is simple in construction for a vehicle.
One more object of present invention is to develop the method for controlling an engine stall which is user friendly and cost effective.
One more object of present invention is to develop a new electric and hydraulic logic based on various sensors input placed in the system.
A method according to an aspect of the present invention is also disclosed.
Further advantageous embodiments and further advantages of the invention emerge from the detailed description below.

SUMMARY OF THE INVENTION
The present invention relates to the method for controlling the hydraulic system in order to control stalling of the engine, by self-regulating the hydraulic pressure of a travel pump, vibration pump and an engine speed.
The method for controlling the hydraulic system effectively prevents the stalling of engine in the earthmoving vehicle. The method for controlling the hydraulic system prevents the stalling of engine when the earthmoving vehicle is in motion.
The method for controlling the hydraulic system includes electronic and hydraulic logic which further utilized for indicate the operator about loading condition further prevent the stalling of the engine.
The method for controlling the hydraulic system includes atleast one engine speed sensor, atleast one vibration pump and atleast one travel pump. One or more sensing means are placed on the vehicle inorder to receive real time pressure inputs from the vibration pump and the travel pump. The inputs received from these sensors or sensing means further transferred to the microcontroller. A certain pre-determined hydraulic pressure values against each the vibration pump and the travel pumps are recorded in the microcontroller to form a logic. A certain pre-determined engine speed value is also recorded in the microcontroller to form the logic.
If the abovementioned one or more received input values are more than the pre-determined recorded values against the vibration pump, the travel pump then an audio type or visual type or both indications against each of these three inputs are activated on a dashboard placed proximity to the operator.
If received input value is less than the pre-determined recorded values against the engine speed then an audio type or visual type or both indications against the engine speed is activated on the dashboard placed proximity to the operator.
This indication triggers the operator to reduce respective value against the engine speed, the travel pump, the vibration pump through a joystick or a lever.
If the operator ignores the audio-visual type indication, then the micro-controller automatically stops or self-regulates the function of either of the travel pump, the vibration pump or the engine speed or all.
Other advantages and features of the present invention will become apparent when viewed in light of detailed description of the preferred embodiment when taken in conjunction with the drawings and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS
With reference to the following drawings, a more detailed description of different exemplary embodiments of the invention will follow below.
In the drawings:
Figure 1 Illustrates the method for controlling an engine stall according to the preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION
A method for controlling an engine stall according to preferred embodiment of the present invention will be described hereinunder with reference to accompanying drawings FIG. 1
As shown in FIG. 1, methods for controlling an engine stall of an utility vehicle or the off-road vehicle, construction, earthmoving vehicle comprising of an engine speed sensor mounted on an alternator in order to receive real time engine speed, a sensing mean mounted on the vibration pump in order to receive real time vibration pressure input, a sensing mean mounted on the travel pump in order to receive real time travel pressure input and a micro-controller unit.
The sensing unit 1 is mounted on the alternator of the engine which measures real time value of the engine speed and further transfers it to the micro-controller unit.
The sensing unit 2 is disposed on the travel pump and used for estimating the real time travel pump pressure. The estimated real time travel pump pressure further transferred it to the micro-controller unit.
The sensing unit 3 is disposed on the vibration pump and used for estimating the real time vibration pump pressure. The estimated real time vibration pump pressure further transferred it to the micro-controller unit.
Certain pre-determined threshold values against each the vibration pressure, the engine speed and the travel pressure are recorded into the micro-controller unit to form the logic.
The micro-controller unit works on the logic where if either of the received sensing or input values against the vibration pressure and the travel pressure through the sensing means are greater than the pre-determined threshold values against each the vibration pressure and the travel pressure are recorded into the micro-controller unit then the audio type or visual type or both indications against each of these both inputs are activated on the dashboard placed proximity to the operator.
The micro-controller unit works on the logic where if the received sensing or input values against the engine speed less than the pre-determined threshold values against the engine speed recorded into the micro-controller unit then the audio type or visual type or both indications against the engine speed is activated on the dashboard placed proximity to the operator.
Further this indication triggers the operator to reduce or increase respective value against the engine speed, the vibration pump, the travel pump through the joystick or the lever.
Yet another embodiment of the present invention, if the operator ignores the audio-visual type indication, then the micro-controller automatically stops or self-regulates the various input values by de-stroking the travel pump.
Another preferred embodiment of the present invention, threshold value for the vibration pressure, the engine speed and the travel pressure ranges between 100- 300 bar, 1000-1600 RPM, 200 - 500 bar respectively are recorded into the micro-controller unit to form the logic.
The micro-controller unit works on the logic where if either of the received sensing or input values against the vibration pressure and the travel pressure through the sensing means are greater than the range 100- 300 bar and 200 - 500 bar respectively then the audio type or visual type or both indications against each of these both inputs are activated on the dashboard placed proximity to the operator.
The micro-controller unit works on the logic where if the received sensing or input values against the engine speed less than the range 1000-1600 RPM then the audio type or visual type or both indications against the engine speed is activated on the dashboard placed proximity to the operator.
Further this indication triggers the operator to reduce or increase respective value against the engine speed, the vibration pump, the travel pump through the joystick or the lever.
The abovementioned description describes the exemplary embodiments of the present invention. One skilled in the art will easily understand from the description and from the accompanying drawings and claims that various changes, modifications and variations can be made therein without changing scope of the invention as defined by the following claims.