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:
SYSTEM TO PROVIDE A SECONDARY SPEED INPUT TO ENGINE CONTROL UNIT

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 202041004188 filed on 30 January 2020.

TECHNICAL FIELD
[002] The present invention relates to an electronic control unit of an engine and more particularly relates to a system of providing a secondary speed input signal to the electronic control unit of engine.
BACKGROUND
[003] An alternator is a type of electric generator used in modern automobiles to charge the battery and to power the electrical system when its engine is running. Modern vehicles now use the compact alternator layout. This is electrically and magnetically similar, but has improved air cooling. Better cooling permits more power from a smaller machine. The casing has distinctive radial vent slots at each end and now encloses the fan. Two fans are used, one at each end, and the airflow is semi-radial, entering axially and leaving radially outwards. The stator windings now consist of a dense central band where the iron core and copper windings are tightly packed, and end bands where the windings are more exposed for better heat transfer. The closer core spacing from the rotor improves magnetic efficiency. The smaller, enclosed fans produce less noise, particularly at higher machine speeds. Typical passenger car and light truck alternators are rated around 50–70 A though higher ratings are becoming more common, especially as there is more load on the vehicle's electrical system with air conditioning, electric power steering and other electrical systems. Very large alternators are used on buses, heavy equipment or emergency vehicles may produce 300 A.
[004] Generally, most of the automobile engines are controlled by a central electronic control unit or in some cases by a dedicated engine control unit. Further, in the automobiles the fuel to engine cylinders is supplied based on the engine speed input or boost pressure inputs. However, in case of Off-high way engines, the fuel supply is controlled based on the engine speed only.
OBJECT OF THE INVENTION
[005] The main objective of the invention is to provide an alternator speed output signal as secondary speed input to engine control unit for engine.
[006] Another object of the invention is to reduce the damage and breakdown of engine.
[007] Yet another object of the invention is to control the fuel supply to engine in case of the engine speed sensor malfunctioning.

SUMMARY
[008] 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 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 aspects related to a method to provide a secondary speed input to the electronic control unit from an alternator speed output, and the aspects are further elaborated below in the detailed description. 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.
[009] In one implementation, a system to provide a secondary speed input to the electronic control unit of engine from an alternator speed output is disclosed. Further, if a speed sensor is malfunctioned, the secondary input may run the engine without speed sensor input. This arrangement ensures smooth running and prevents breakdown of engine.

BRIEF DESCRIPTION OF THE DRAWINGS
[0010] 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.
[0011] 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.
[0012] Figure 1(a) and 1(b) shows speed sensor configured near flywheel housing, according to an embodiment of the present subject matter.
[0013] Figure 2 shows connection and terminals of alternator speed sensor according to an embodiment of the present subject matter.
[0014] Figure 3 shows flowchart of the alternator speed input to ECU system.
[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 engine of an automobile is controlled by an engine control unit to obtain optimized engine efficiency. More specifically the fuel supply to engine cylinders is controlled by the engine control unit based on the engine speed input. To provide the engine speed input, a speed sensor is used. However, in case of malfunctioning of the speed sensor, the engine efficiency gets deteriorated. Hence, the present disclosure discloses a method to provide a secondary speed input to the electronic control unit from an alternator speed output. The speed of the alternator depends on the speed of the engine that may be driven by an alternator belt pulley through engine drive parts. The engine control unit may continuously monitor the alternator speed output and matches a speed ratio between the alternator speed and engine speed. Further, the alternator speed output may be provided to the engine control unit as the secondary speed input. In case of malfunctioning of the speed sensor, the alternator speed output functions as the secondary speed input to run the engine without the speed sensor input.
[0019] Referring now to Figure 1(a) and 1(b) it shows the flywheel housing (20) comprising of engine speed sensor, engine control unit not shown in figure and flywheel (30), flywheel teeth (36), alternator speed sensor (40) and gap (34) of 1 to 1.5 mm between flywheel teeth (36) and alternator speed sensor (40). Encoder not shown in figure is configured with number of flywheel teeth and alternator speed ratio. Alternator speed ratio is calculated between to alternator pulley drive rotational speed N1 to Engine Speed N2.
Alternator speed ratio = N1/N2
Where, N1= Alternate pulley drive speed.
N2= Engine Speed (Flywheel).
[0020] Referring now to Figure 2 it shows the connection established form the alternator to provide the alternator speed output (60) as secondary speed input the ECU. The positive line of the battery (50) may be connected to POS terminal of an alternator while the negative terminal of the battery may be connected to a body ground of the alternator. Further, CN-ALT cable may be connected to lamp (46) terminal of the alternator.
[0021] Referring now to Figure 3 it shows the flowchart of the alternator speed input to ECU system. On initial cranking of engine the engine control unit starts engine using speed sensor input from engine. When an abnormal or failure of engine speed sensor occurs engine fuel control is established by taking speed input from alternator.
[0022] Further, the invention can be used, but not limited to, in the following applications.
[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 may reduce damage and break down of a heavy-duty engine.
[0025] Some embodiments may enable to save cost to repair a damaged engine due to speed sensor malfunctioning.
[0026] REFERRAL NUMERALS:

Element Description Reference Numeral
Flywheel Housing 20
Flywheel 30
Flywheel teeth 36
Alternator speed sensor 40
Lamp 46
Gap 34
Battery 50
alternator speed output 60

,CLAIMS:
1. Secondary speed input system to engine ECU comprises of;
atleast one engine speed sensor for providing engine speed to ECU;
atleast one encoder configured to process alternator speed signal;
and atleast one alternator speed sensor (40) to provide alternator speed output (60) to ECU for controlling fuel supply to engine.

2. Secondary speed input system to engine ECU as claimed in claim 1, wherein said alternator speed sensor (40) is configured to be mounted on flywheel housing (20).

3. Secondary speed input system to engine ECU as claimed in claim 1, wherein the encoder is configured to process the alternator speed signal based on alternator pulley drive speed (NI) / engine speed (N2).

4. Secondary speed input system to engine ECU as claimed in claim 1, wherein the system to provide alternator speed output (60) to engine ECU is configured by connecting positive line of the battery (50) to POS terminal of an alternator and the negative terminal of the battery is connected to a body ground of the alternator.

5. Secondary speed input system to engine ECU as claimed in claim 1, wherein said alternator speed sensor (40) provides signal to engine ECU in absence of engine speed sensor signal to control fuel supply to engine.

6. Secondary speed input system to engine ECU as claimed in claim 1, wherein the alternator speed sensor input to engine ECU is configured to prevent the damage and breakdown of engine.