FORM – 2
THE PATENTS ACT, 1970
(39 OF 1970)
PROVISIONAL SPECIFICATION
(See Section 10)
TITLE OF INVENTION
"Governing System for Engine and Method of Operating Thereof"
a) Mahindra & Mahindra.Ltd.
(b) R&D Centre, Automotive Devision, 89, M.I.D.C.,Satpur, NASHIK-422007.
The following specification particularly describes the nature of the invention
Field of Invention
The invention relates to a fuel injection system. In particular the invention relates to a governing system of the engine and a method of operating the same.
Background of the Invention
The fuel input into the combustion chamber of an internal combustion diesel engine is controlled by Fuel Injection System. This fuel flow shall be controlled by different types of fuel injection system depending upon the engine performance requirements. The quantity of the fuel to be injected depends upon the fuel rack position as well as the time of injection. In order to meet the engine requirements the fuel injection quantity is controlled by the mechanical governor and the time of injection is controlled by the mechanical timer.
The flyweight of mechanical governor is driven by the engines camshaft which acts against the force of governor spring connected to the control rack by a system of levers. During static operation centrifugal and spring forces are in a state of equilibrium with the control rack positioned for the delivery quantity corresponding to the engines output at the respective point of its performance curve. A drop in engine speed for instance due to increased load results in a corresponding reduction in centrifugal force and the governor springs move the flyweights and with them the control rack in the direction for increased delivery quantity until equilibrium is restored.
If the fuel quantity governed by the conventional mechanical governing system is not precise then undesirable fuel get injected into combustion chamber will cause incomplete combustion, increase of smoke, undesired performance. Precise fuel control is affected by poor response time the mechanical system and reliability of the system is very much limited by the spring mechanism. Mechanical governors are bulky and have more moving parts. This makes the system response sluggish.


United States Patent 5591021 discloses a fuel-injection pump for internal combustion engines, particularly an in-line injection pump for diesel engine, with a control bore in the pump cylinder and with an upper control edge for determining the start of feed and an oblique spill edge for determining the end of feed. The pump piston is rotated about its longitudinal axis in order to set the desired feed quantity, for the purpose of achieving a better regulating behavior of the system as a whole, comprising the fuel-injection pump, feed-quantity regulator and internal-combustion engine. The spill edge is subdivided, along its run over a part of the circumference of the pump piston, into portions with different angles of inclination to the axis of the pump piston.
United States Patent 7293548 discloses a high pressure fuel pump control apparatus for an engine can suppress or avoid uncontrolled fuel delivery of a flow control valve upon delivery of a maximum amount of fuel, and resultant great deterioration in drivability and exhaust gas. An advance angle setting limiting section limits a closed position of the flow control valve from being set to a location advanced from a predetermined advance angle limiting position. A flow control valve control section decides a target pressure in accordance with an engine operating condition, and sets the closed position such that the fuel pressure coincides with the target pressure.
United States Patent 4616616 discloses a fuel control system which includes a hydraulic servo system for moving a fuel rack in response to movement of a rack control member. A brushless direct current torque motor, having a rotor and a control lever fixed thereto, is arranged with its lever end confined between opposed shoulders on the rack control member. Electronically energized movement of the rotor and its control lever in one direction, or spring biased movement in the other, causes corresponding movement of the control member and fuel rack. A second control lever movable by a mechanical governor control is engageable with another shoulder on the rack control member to move it in a fuel-decreasing direction.
United States patent 657359 discloses a fuel supply system for an internal combustion engine, wherein the speed or discharge pressure of a fuel pump is feedback controlled


depending on fuel pressure monitored by a fuel pressure sensor. Returnless piping structure has been proposed for simplifying the fuel piping and lowering the fuel temperature in a fuel tank to prevent vapor formation therein. The returnless piping structure eliminates a fuel return line for returning an excessive portion of fuel, which is delivered under pressure from a fuel pump to fuel injectors (fuel injection valves), to the fuel tank.
US 70830202 discloses an automatic stop/start controller for a vehicle which automatically stops and starts a vehicle engine without operation of an ignition key, wherein: a control unit automatically stops the engine without operation of the ignition key when a condition of vehicle speed is less than or equal to a predetermined vehicle speed, when a condition of distance of travel of the vehicle is more than or equal to a predetermined automatic stop prohibit distance before stop, and when a condition in which a direction indicator of the vehicle is deactivated, are at least satisfied; the control unit automatically starts the engine immediately without operation of the ignition key if the direction indicator is activated after the engine is automatically stopped without operation of the ignition key.
Thus the study of the related prior art reveals major technological gaps such as:
 complex system with substantial number of moving parts resulting in reducing the response time of the system that negatively affects fuel economy
 governing, based on the average speed that results in damping response of the system
 inconsistency in low idle and high idle and dependency on fuel rack position
 substantial power consumption by the system itself
 substantial weight of the system is less due to linkages and flyweights.
 use of oil seals.
 number of moving parts makes it difficult to control the system precisely resulting in emission problems


 noise and vibration in the system because of the weight and number of moving
components
 substantial lubrication requirement
 difficult to assemble and replace the system and components.
Necessity has constantly been felt to develop an engine governing system with substantially low response time, reduced moving parts, having capability of adapting and integrating with the available fuel injection pumps.
Summary of the Invention
The main object of the invention is to provide a governing system for an engine. It is the further object to provide an integrated governing system with fuel injection pump of engine.
Yet another object of the invention is to provide a governing system for an engine with a mono block mechanical unit pump.
Another object of the invention is to substantially reduce response time of the system.
Another object of the invention is to provide a simple mechanism with substantially reduced moving parts for governing of the engine.
Yet another object of the invention is to substantially reduce weight of the governing system.
Another object of the invention is to integrate operations such as engine speed governing, vehicle speed limiter control, EGR Control, mild start/stop, cooling fan ON/OFF control and fuel lift pump control with the governing system.
Yet another object of the invention is to provide easily maintainable system.


Yet another object of the invention is to enhance fuel economy.
Another object of the invention is to achieve consistency in low idle and high idle irrespective of the fuel rack position
Yet another object of the invention is to substantially reduce power consumption of the system.
Another object of the invention is to reduce noise and vibration in the system.
Another object of the invention is to govern the system based on the instantaneous speed.
Yet another object of the invention is to substantially reduce lubrication requirement of the system.
Another object of the invention is to enhance /ease starting process of the engine thereby enhancing life of starter motor.
Thus in accordance with the invention, the fuel injection system comprises of:
a mono block mechanical fuel injection unit pump;
a rotating means that rotates in increments / steps wherein speed of rotation is
determined by the time delay between each increment;
control unit configured with the said rotating means and engine sensors;
wherein the said rotating means is operably connected to the lead screw shaft to
convert rotational motion in linear motion wherein the said lead screw shaft is adapted
to fit the fuel control rack of the said fuel injection unit pump;
wherein


the stepwise increment/s of the said rotating means is actuated by the said control unit based on the feedback from various sensors of the engine to precisely control the fuel input to the engine.
Description of the Invention
Features and advantages of this invention will become apparent in the following detailed description and the preferred embodiments with reference to the accompanying drawings.
Figure 1 Schematic of the system (Sheet 1)
Figure 1 depicts schematic of the configuration of the governing system of the present invention. The system comprises of a mono block mechanical fuel injection unit pump 1, rotating means 7 that rotates in increments / steps and the control unit 13 with sensors configured with the rotating means. The figure indicates two cylinders (2 and 3) of the engine 4 as representation however, it is possible to use engines of a single, two and three cylinders in one of the preferred embodiment. The invention is not limited by the number of cylinders of the engine. The said cylinders of the engine are operably connected through fuel lines 5 and 6 to the said pump unit assembly 1 that comprises of two pumps 20 and 21 as shown in the Figure. The said rotating means 7 is operably connected to the lead screw shaft 8 to convert rotational motion in linear motion wherein the said lead screw shaft is adapted to fit the fuel control rack 9. In another embodiment unit link, split link with thread joint ,riveted joint, Rack & Pinion arrangement, piston with linkage mechanism etc. can be used in place of lead screw shaft to convert rotational motion in linear motion. The said control rack 9 has a linear motion (as indicated by the arrow 10) proportional to the incremental / stepwise rotation of the said rotating means. The said control rack is operably connected through control arms 11 and 12 to the said pump 1. The metering of fuel in the engine is a function of the control arm position which in turn is a function of the linear motion of the fuel control rack 9 which is positioned by the lead screw 8 based on the increments of the said


rotating means 7. The control unit is configured with the sensors such as engine speed sensor, throttle position sensor but not limited to it. Further, the said control unit is configured with the said rotating means 7 and the pump 1. In one of the embodiment the said throttle position sensor is selected from resistance, inductive type, piezotype.. The of the said control means with these is represented by the lines 20, 21 and 22. The said control unit 13 is further configured with cluster of sensors indicated by 14 that include engine coolant sensor, fuel rack position sensor, W-terminal sensor that is mounted on alternator of the engine to indirectly measure engine speed, vehicle speed sensor but not limited to it and the actuators such as cooling fan actuator (not shown). In one of the embodiments the speed sensors are Hall effect, inductive type sensors. The governing system of the present invention operates to maintains engine speed with desired limits by regulating / metering the amount of fuel based on the feedback of the various sensors thereby adjusting the fuel pump delivery to meet the various operating conditions of the engine.
In one of the embodiments governing system of the present invention is integrated with a vehicle speed limiting means.
In yet another embodiment the governing system of the present invention is integrated with the engine starting system to control the starter motor according to operating condition, driver intention.
In yet another embodiment the governing system of the present invention is integrated to control the cooling fan of the engine.
In yet another embodiment the said governing system changes fuel control rack linear direction.
In yet another embodiment the governing system of the present invention is used to integrate cruise control, traction control of the vehicle.


In yet another embodiment the governing system of the present invention is integrated with a solenoid of fuel Injection Pump.
In yet another embodiment the governing system of the present invention adapted to run the generator setup, air compressor.
Thus it is evident that the synergistic combination and configuration of the a mono block
mechanical fuel injection unit pump, a rotating means that rotates in increments / steps
control unit configured with the said rotating means and sensors and the
means to convert rotational motion in linear motion results in precise control of the
precisely control the fuel input to the engine based on the instantaneous speed of the
engine obviating the problems associated flyweight, linkages etc. thereby substantially
reducing the response time of the system that results in better / improved fuel economy,
reducing emission, offering consistency in low and high idle, reducing power
consumption and vibration of the system yet providing capability of adapting and
integrating with the available fuel injection pumps and achieving substantially low