DESC:FORM 2

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

COMPLETE SPECIFICATION
(See Section 10 and Rule 13)

Title of invention:
AN ELECTRONIC SYSTEM FOR SETTING OF FUEL INJECTION TIMING IN IC ENGINE AND METHOD THEREOF

Applicant:
BEML Limited
A company Incorporated in India under the Companies Act, 1956
Having address:
BEML Soudha, 23/1, 4th Main,
Sampangirama Nagar, Bengaluru - 560 027,
Karnataka, India

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

CROSS-REFERENCE TO RELATED APPLICATIONS AND PRIORITY

[001] The present invention claims priority from Indian patent Provisional Application 202041044706 filed on 14 October 2020.
TECHNICAL FIELD
[002] The present subject matter described herein, in general, relates to a system and a method for setting of fuel injection timing in an IC engine and more specifically relates to an electronic system for fuel injection time setting in the IC engine.
BACKGROUND
[003] Generally, to regulate the pollution emitted by cars and two-wheelers, the government has set regulations termed as Bharat Stage Emission Standards (BSES). According to BSES, an emission level of pollutant gases including particulate matter and NOx has been set. Further, the emission of particulate matter and NOx is an important parameter to decide an engine performance. However, during engine optimization, the emission level of particulate matter and NOx can be varied to meet the emission norms.
[004] Basically, the engine emissions are also based on a fuel injection timing in an engine cylinder and hence, the fuel injection timing plays vital role. Further, the fuel injection pump is an important part of engine as it supplies fuel to number of cylinders at desired pressure and time. Timing and pressure at which fuel is supplied to various cylinders is very important. So, the fuel injection time optimizing is a crucial parameter.
[005] Generally, the fuel injection time is adjusted by varying an angle of a crank wherein the angular markings are provided on a smooth circumference surface of the fuel injection pump and to set the fuel injection pump to a desired crank angle, a pointer is provided near the said surface. In majority of engines, the angular markings are provided on a damper of the fuel injection pump. Conventionally, the fuel injection time optimizing is done manually and there is possibility of human error while optimizing the desired crank angle or optimizing the fuel injection timing. In some cases, the damper diameter is so small that the marking for each degree is absent on the damper. In such cases, user need to set the desired crank angle by approximation. There is difficulty in accessibility to timing marks as markings are not clear or may be small in some cases.
[006] Hence, there is a need to provide a system that eliminates the approximation and error, and which facilitates an accurate fuel injection time optimizing.

OBJECT OF THE INVENTION
[007] It is a main object of the present invention to provide an electronic system for accurate setting of fuel injection timing in an IC engine.
[008] It is an object of the present invention to provide a digital display for displaying fuel injection timing.
[009] It is an object of the present invention to eliminate human error in setting fuel injection timing.
SUMMARY
[0010] Before the present system and method are described, it is to be understood that this application is not limited to the particular machine or an apparatus, and methodologies described, as there can be multiple possible embodiments that are not expressly illustrated in the present disclosures. 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 aspects related to setting of a fuel injection timing through an electronic system. This summary is not intended to identify essential features of the proposed subject matter nor is it intended for use in determining or limiting the scope of the proposed subject matter.
[0011] The present subject matter relates to an electronic system for setting of fuel injection timing in an IC engine comprising:atleast one tacho drive configured to be connected to an engine camshaft for transmitting a rotary motion of the engine camshaft, atleast one rotary potentiometer configured to be connected to the tacho drive to convert rotary motion to voltage signal, a microcontroller configured to be connected to the rotary potentiometer wherein the microcontroller is configured to supply voltage to the rotary potentiometer to convert an output voltage of the rotary potentiometer to determine an engine crank angle and an alphanumeric display configured to display the engine crank angle. In the said electronic system, the engine crankshaft is configured to rotate the tacho drive gear through the engine camshaft. Further, the rotary potentiometer is configured to be connected to the tacho drive after optimization of a first cylinder TDC position. Furthermore, a damper of the IC engine is configured for marking of the TDC position of the first cylinder.
[0012] Further, a method of operating the said electronic system for setting of fuel injection timing in an IC engine comprises the steps of: optimizing a first cylinder firing TDC position with help of TDC marking on a damper of the IC engine and a pointer located near the damper, connecting a tacho drive to an engine camshaft, connecting a rotary potentiometer to the tacho drive, connecting a microcontroller to the rotary potentiometer, connecting an alphanumeric display to the microcontroller, rotating an engine crankshaft to a predetermined angle by observing a value on the alphanumeric display and optimizing the required engine crank angle or a fuel injection timing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The foregoing summary, as well as the following detailed description of embodiments, 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.
[0014] 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.
[0015] Figure 1 illustrates a damper with a pointer and markings.
[0016] Figure 2 illustrates a tacho drive of the proposed system.
[0017] Figure 3 illustrates a rotary potentiometer of the proposed system.
[0018] Figure 4 illustrates a flowchart for setting a fuel injection timing by the proposed system.
[0019] The figure depicts various embodiments of the present disclosure for purposes of illustration only. One 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
[0020] 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.
[0021] Various modifications to the embodiment will be readily apparent to those skilled in the art and the generic principles herein may be applied to other embodiments. 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.
[0022] The present subject matter discloses an electronic system for setting a fuel injection timing of a fuel injection pump in an IC engine. The proposed system comprises a tacho drive to act as coupling, a rotary potentiometer to convert a rotary motion to a voltage signal, a microcontroller to supply voltage and to send a signal to a display unit and an alphanumeric display to read an output signal of the microcontroller.
[0023] Referring to figure 1, line markings on a damper (102) of an IC engine along with a pointer (108) is shown. The damper (102) is a smooth circumference component of an IC engine and mounted on an engine camshaft. Generally, there are two type of markings provided on the damper (102) wherein the first marking (104) is for optimizing an angle of a crank which also represents a fuel injection timing and the second marking (106) is provided for optimizing top dead center (TDC) or an engine cylinder position. There may be multiple TDC markings on the damper (102) depending on number of cylinders in the IC engine. As shown in the figure 1, there may be a single marking (106) for cylinder 1 and cylinder 6. Further, as shown, there may be multiple line markings (104) with the crank angle marked on each line. For setting the fuel injection timing through the proposed electronic system, a first cylinder firing TDC position is set by matching the provided TDC line marking (106) with a pointer (108) as shown in figure 1.
[0024] Referring to figure 2, a tacho drive (200) used in the present invention is shown. The tacho drive (200) may be configured to be connected to the engine camshaft. As the IC engine rotates, a drive gear (202) the tacho drive also rotates along with the engine camshaft and the damper. The tacho drive (200) may be configured to be coupled to the engine camshaft and a rotary potentiometer (300). A driven gear (204) of the tacho drive (200) may be connected to the rotary potentiometer (300). The tacho drive (200) may also be known as revolution pick up.
[0025] Referring to figure 3, a rotary potentiometer (300) of the proposed invention is shown. The rotary potentiometer (300) is very known and generally converts a rotary motion to a voltage signal. The rotary potentiometer comprises three terminals (a, b, c) and a sliding or rotating contact that acts as an adjustable voltage divider. The slider may move clockwise or anticlockwise as the IC engine rotates. When the engine crank shaft rotates to set a desired crank angle, for example 20 degrees before top dead centre (BTDC), the rotary potentiometer (300) also rotates through the tacho drive (200) and hence an output voltage of the rotary potentiometer (200) may get varied. In the present invention, the output voltage may be interpolated with respect to the crank angle.
[0026] Further, the microcontroller is used in the proposed system to supply reference voltage to the rotary potentiometer (300) and to convert an output voltage of the rotary potentiometer (300) to the engine crank angle in degree. After converting the output voltage to the engine crank angle, a value of the engine crank angle in degrees is sent to an alphanumeric display. Further, the alphanumeric display unit reads a signal sent by the microcontroller and displays the engine crank angle value in degrees. The display unit may also be equipped with a reset button wherein the reset button resets the engine crank angle value to “0” degrees.
[0027] Referring to figure 4, a flowchart of the proposed system is shown. For setting the engine crank angle or the fuel injection timing, the engine may be rotated such that the first cylinder firing TDC position marked on the damper is matched with the pointer (108). After optimizing the first cylinder firing TDC position, the rotary potentiometer (300) may be connected to the tacho drive (200) and then a power may be switched on. After turning on the switch, the engine crank angle value may be observed on the alphanumeric display unit and if the engine crank angle value is 0 degree, then the engine crank shaft may be rotated to set a required engine crank angle and if the engine crank angle value is other than 0 degree then the reset button on the display unit may be pressed to set the engine crank angle to 0 degree.
[0028] Further, a method to set the fuel injection timing by the proposed electronic system is disclosed. The first cylinder is set to the firing position at TDC. For optimizing the firing position TDC, the TDC marking on the damper is matched with the pointer (108) located near the damper. Further, the tacho drive (200) is connected to the engine cam shaft and then the rotary potentiometer (300) is connected to the tacho drive (200). The rotary potentiometer (300) is connected to the microcontroller and the microcontroller in turn is connected to the alphanumeric display unit. Further, to set the required engine crank angle or to set the required fuel injection timing, the engine crankshaft is rotated. As the engine crankshaft rotates, the rotary potentiometer (300) also rotates through the tacho drive (200) and the rotated angle is displayed on the alphanumeric display unit. As the engine crank angle value is visible on the alphanumeric display, the value may be precisely set to the required crank angle.
[0029] 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.
[0030] Some object of the present invention provides accurate fuel timing setting in an IC engine.
[0031] Some object of the present invention provides setting of fuel injection timing without any timing mark on a damper of an IC engine.
[0032] Some object of the present invention provides a digital display to ensure a value of required fuel injection timing.
[0033] Some object of the present invention eliminates human error during setting of a fuel injection timing.
[0034] Some object of the present invention ensures a precise setting of a fuel injection timing where an accessibility to timing mark is difficult.
[0035] Some object of the present invention eliminates difficulty in adjusting fuel injection timing from fuel cut off position.
[0036] Some object of the present invention helps in adjusting a fuel injection timing during cross checking.
[0037] Some object of the present invention helps in setting a fuel injection timing whenever fuel injection pump is replaced.
[0038] Some object of the present invention provides time reduction in setting a fuel injection timing.
[0039] Some object of the present invention improves an IC engine safety.
[0040] Following are the reference numerals used in figures according to the present invention.
Reference No. Part Name
102 Damper
104 First marking
106 Second marking
108 Pointer
200 Tacho drive
202 Drive Gear
204 Driven Gear
300 Potentiometer

,CLAIMS:
1. An electronic system for setting of fuel injection timing in an IC engine comprising:
at least one tacho drive (200) configured to be connected to an engine camshaft for transmitting a rotary motion of the engine camshaft;
at least one rotary potentiometer (300) configured to be connected to the tacho drive (200) to convert rotary motion to voltage signal;
a microcontroller configured to be connected to the rotary potentiometer (300) wherein the microcontroller is configured to supply voltage to the rotary potentiometer (300) to convert an output voltage of the rotary potentiometer (300) to determine an engine crank angle; and
an alphanumeric display configured to display the engine crank angle.
2. The electronic system for setting of fuel injection timing in the IC engine as claimed in claim 1, where in the engine crankshaft is configured to rotate the tacho drive gear (202) through the engine camshaft.
3. The electronic system for setting of fuel injection timing in the IC engine as claimed in claim 1, wherein the rotary potentiometer (300) is configured to be connected to the tacho drive (200) after optimizing of a first cylinder TDC position.
4. The electronic system for setting of fuel injection timing in the IC engine as claimed in claim 1, where in a damper (102) of the IC engine is configured for marking of the TDC position of the first cylinder.

5. A method of operating the said electronic system for optimization of fuel injection timing in an IC engine comprises the steps of:
optimizing a first cylinder firing TDC position with help of TDC marking on a damper (102) of the IC engine and a pointer (108) located near the damper (102);
connecting a tacho drive (200) to an engine camshaft;
connecting a rotary potentiometer (300) to the tacho drive (200);
connecting a microcontroller to the rotary potentiometer (300);
connecting an alphanumeric display to the microcontroller;
rotating an engine crankshaft to a predetermined angle by observing a value on the alphanumeric display;
setting the required engine crank angle or a fuel injection timing.