FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
PROVISIONAL SPECIFICATION
(See section 10, rule 13)
"STARTER GENERATOR FOR VEHICLE"
MINDA CORPORATION LIMITED, an Indian company, of E-5/2, Chakan Industrial Area, Phase-Ill, M.I.D.C., Nanekarwadi, Tal: Khed, Dist. Pune - 410501, Maharashtra, India
The following specification particularly describes the invention;

"STARTER GENERATOR FOR VEHICLE"
TECHNICAL FIELD
The present disclosure relates to an integrated starter generator motor for IC engine used for starting engine, generating electric power to charge the battery and controlling idle stop function. Basic elements of the integrated starter generator are motor/generator and Electronic Control Unit.
BACKGROUND
Generally, motor/generator is a 30 brushless motor with rotor position sensors. Motor/Generator has three basic parts- Stator, Rotor and sensor assembly. Stator has n number of poles of coils wounded on iron core. Electric current flows through the coils, because of varying electric current magnetic flux generated. Rotor is a cup shaped part, having m number of poles of permanent magnets. Rotor is mounted on crank shaft. Because of magnetic flux generated by stator currents, rotor starts rotating and hence crank shaft rotates.
In a brushless motor, position of the rotor relative to the stator is required to be determined so that the windings in the stator can be energized based on position of the rotor to effect relative angular movement between the stator and the rotor. In order, to sense the position of the rotor, position sensors are used. These magnetic sensors are generally placed 120° (electric angle) apart. Because of high current flow through the stator coils, temperature of the stator becomes high. As rotor position sensors are placed in inner periphery of the stator, performance of the sensors may degrade due to high temperature. On the other hand, only temperature

sensors which can perform in such high temperature environment can be used in such assemblies. Moreover, mounting of the sensors inside periphery of the stator is cumbersome.
Present disclosure is directed to address one or more problems as discussed above and other problems associated with the art.
SUMMARY
One or more drawbacks of conventional motor/ generator as described in the prior art are overcome and additional advantages are provided through a starter generator as claimed in the present disclosure. Additional features and advantages are realized through the technicalities of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered to be a part of the claimed disclosure.
In one non-limiting embodiment of the present disclosure, there is provided a starter generator for vehicle. The starter generator comprises a base plate and a rotor. The rotor is movably attached to the base plate. The rotor comprises a side wall, a cavity and a stator. The cavity is configured to accommodate the stator therein. The cavity is encapsulated through the side wall. A plurality of sensing elements is disposed at an outer surface of the said side wall. A set of position sensors is rigidly mounted on the base plate. The set of position sensors is placed outside periphery of the rotor to sense the sensing elements.
In an embodiment, at least one of the position sensors is a hall sensor,

In an embodiment, the set of position sensors is placed one after another at a gap of 120 degrees electric angle between two consecutive sensors.
In an embodiment, at least one of the position sensors is cuboidal in shape.
In an embodiment, at least one of position sensors is mounted such that the longitudinal length of the position sensors is oriented orthogonal to a planar surface of the base plate.
In an embodiment, the set of position sensors is electronically connected to Electronic Control Unit (ECU) of the vehicle.
In an embodiment, a plurality of magnets is mounted on an inner surface of the side wall of the rotor, the plurality of magnets is positioned consecutively with alternate north and south pole configuration.
In an embodiment, the plurality of sensing elements is positioned corresponding to either north poles of the plurality of magnets or south poles of the plurality of magnets.
In an embodiment, the base plate includes a protrusion, the protrusion is configured for mounting of the stator.
The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent with reference to the drawings and the following detailed description.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The novel features and characteristics of the disclosure are set forth in the appended description. The disclosure itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying figures. One or more embodiments are now described, by way of example only, with reference to the accompanying figures wherein like reference numerals represent like elements and in which:
Figure 1 illustrates a perspective view of a starter generator in accordance with an embodiment of the present disclosure.
Figure 2 illustrates a top view of the integrated starter generator of figure 1, according to an embodiment of the present disclosure.
Figure 3 illustrates a perspective view of a stator and a base plate with the position sensors in accordance with an embodiment of the present disclosure.
Figure 4 illustrates a perspective view of a base plate with the position sensors in accordance with an embodiment of the present disclosure.
Figure 5 illustrates a cross-sectional view of the integrated starter generator taken along line 5-5 of figure 2.
Figure 6 illustrates a rotor in accordance with an embodiment.
Figure 7 illustrates a rotor in accordance with an embodiment.

The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the assemblies and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
DETAILED DESCRIPTION
While the invention is subject to various modifications and alternative forms, specific embodiment thereof has been shown by way of example in the figures and will be described below. It is to be noted that a person skilled in the art can be motivated from the present disclosure and can perform various modifications. However, such modifications should be construed within the scope of the invention.
The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that an assembly, setup, system, device that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such system or device or setup. In other words, one or more elements in the system or apparatus or device proceeded by "comprises a" does not, without more constraints, preclude the existence of other elements or additional elements in the assembly or system or apparatus.
Accordingly, it is an aim of the present disclosure to provide a starter generator for vehicle that is economical.
Another aim of the present disclosure is to develop a starter generator having design flexibility.

Accordingly, the present disclosure provides a starter generator for vehicle. The starter generator may be integrated with an internal combustion engine (not shown). The starter generator may be used for starting engine, generating electric power to charge the battery and controlling idle stop function, or other functions as suitable.
As shown in figures 1-5, the starter generator (10) has a rotor (12), a stator (14), a base plate (16), a boss (18) and a set of position sensors (20, 22, 24). The starter generator (10) may be coupled to an electronic control unit (not shown). In the embodiment as shown, the starter generator (10) is a three-phase brushless DC motor.
The rotor (12) includes magnets or magnetized portions as known in the art. Figures 6 and 7 illustrate the arrangement of the north and south poles of magnets in the rotor (12). The rotor (12) is a cup shaped part, having m number of poles of permanent magnets. The rotor (12) has a cavity to accommodate the stator (14) therein. The cavity is encapsulated through a side wall (28) of the rotor (12). On an outer surface (26) of the side wall (28) of the rotor (12), a plurality of sensing elements (30) is disposed. Whereas, on an inner surface of the cylindrical wall, a plurality of magnets (38) is provided. The plurality of magnets (38) is positioned consecutively with alternate north and south pole configuration. The number of sensing elements correspond to the number of magnets. The number of sensing elements may be equal to the number of the magnets. The number of magnets may vary as required. The sensing elements are rigidly attached with the rotor (12) on the outer surface (26). In the embodiment as shown, one sensing element (30) is provided for each of the north poles on the rotor (12), as shown in figure 6. In an alternate embodiment, as shown in

figure 7, the sensing element (30) may be provided for each of the south pole of the magnets in the rotor (12). The angular length of the sensing elements (30) corresponds to the angular length of the magnet poles. The sensing elements (30) provided for sensing for relative position of the rotor (12) and the stator (14) as described later herein. The sensing elements (30) may be made of any suitable material such as metal. The boss (18) is fitted with the rotor (12) in an opening (32) on a top surface (34) of the rotor (12) to facilitate mounting of the rotor (12) on a crank shaft of an engine.
Further, the rotor (12) is movably attached to the base plate (16) whereas the stator (14) is rigidly mounted on the base plate (16). The windings on the stator (14) are not shown in the drawings for simplicity in illustration. In the embodiment as illustrated, the stator (14) and the base plate (16) are provided with three corresponding bolt holes to facilitate fixing of the stator (14) on the base plate (16).
The base plate (16) is in form of circular plate. The base plate (16) is provided with a protrusion (36) in the center to provide a supporting and guiding surface for mounting the stator (14) on the base plate (16), as shown in figures 4 and 5. The protrusion (36) is circular in shape. The base plate (16) may be made of the any suitable material, for example metal.
As known, for operation of the brushless motor, it is required to provide current to the windings on the stator (14) based on the relative angular position of magnets of the rotor (12). The position sensors (20,22,24) used in the starter generator (10) as disclosed herein can be any position sensor such as hall sensors, proximity sensors, etc. In the embodiment as illustrated, the position sensors (20,22,24) are magnetic sensors and three position sensors (20,22,24) are provided, namely a first position sensor

(20), a second position sensor (22) and a third position sensor (24). The set of position sensors (20,22,24) may be elongated in shape. In the embodiment as shown, the sensors are cuboidal in shape. Further, the set of position sensors (20,22,24) are rectangular in cross-section.
Each position sensor is placed one after another at a gap of 120 degrees electric angle between two consecutive position sensors (20,22,24). The position sensors (20,22,24) of the starter generator (10) are rigidly mounted on the base plate (16). The position sensors (20,22,24) are mounted such that the longitudinal length of the position sensors (20,22,24) is oriented orthogonal to the planar surface of the base plate (16), as shown in figures 1 to 5. Any suitable mechanism may be provided for mounting of the position sensors (20,22,24) on the base plate (16). Further, suitable provisions may be provided for connection of the position sensors (20,22,24) with the ECU.
The position sensors (20,22,24) are placed outside periphery of the rotor (12) to sense the sensing elements (30). A gap is provided between the stator (14) and the position sensors (20,22,24) such that the cylindrical wall (28) of the rotor (12), along with the sensing elements (30) attached to the outer surface (26) of the cylindrical wall (28), can be accommodated between the position sensors (20,22,24) and the stator (14). The gap is such that the rotor (12) can move relative to the stator (14) and position sensors (20,22,24) without any interference from the position sensors (20,22,24) or the stator (14). However, the gap between the position sensors (20,22,24) and the sensing elements (30) can be kept to minimum to ensure proper sensing of the sensing elements (30) by the position sensors (20,22,24). Accordingly, the position sensors (20,22,24) are mounted outside the stator

(14). Figures 1, 2 and 5 illustrate the assembled condition of the starter generator (10) as disclosed herein.
In the embodiment as illustrated, to facilitate mounting of the position sensors (20,22,24), the base plate (16) has been provided with a diameter slightly greater than the diameter of the rotor (12). In an alternate embodiment the base plate (16) may be provided with a mere extension plate for facilitating the mounting of the position sensors (20,22,24) thereon. Any other suitable provision may be provided for mounting of the position sensors (20,22,24) outside the stator (14).
Working of the starter generator (10) is explained as following. The position sensors (20,22,24) detect proximity of the sensing elements (30) to determine relative positioning of the rotor (12) and the stator (14). When the sensing element is in proximity with the position sensor, the position sensor detects presence of north pole of the magnet of the rotor (12) and generates a corresponding signal to the ECU. For example, as shown in Figures 2 and 5, the first position sensor (20) and the third position sensor (24) are in proximity with the sensing element, hence the first position sensor (20) will determine position of the north pole and accordingly signal the ECU to provide current to stator windings to effect angular movement of the rotor (12) relative to the stator (14). Similarly, when the sensing element is away from the position sensor, the position sensor will determine absence of north pole, or in corollary, presence of south pole proximate to the position sensor. Accordingly, the second sensor will signal the ECU so that ECU can send current to the stator windings as required. For example, as shown in figure 2, the second position sensor (22) is away from any sensing element. Accordingly, the second position

sensor (22) will detect presence of south pole of the magnet of the rotor (12) and signal the ECU based on the detection.
For ascertaining proximity, the position sensors (20,22,24) may be configured to detect presence or absence of element if the sensing elements (30) are present or absent within a threshold distance from the position sensor. Any suitable threshold distance value may be selected depending on the size and configuration of the starter generator (10).
Rotor position sensors (20,22,24) are mounted outside the stator (14) and the rotor (12) of the motor/generator. As shown in figures 1 to 5, three position sensors (20,22,24) are mounted on base plate (16) at 120° apart from each other. As shown in figures 1, 2 and 5, sensing elements are mounted on the rotor (12). The angular length of the sensing element is t° and it is overlapping on North Pole or South Pole of the permanent magnets in the rotor (12).
Since the position sensors (20,22,24) are mounted outside the stator (14), the position sensors (20,22,24) will not be exposed to high temperatures which are generated in the stator (14). Therefore, the temperature configuration of the position sensors (20,22,24) used herein may be comparatively lesser. Further, since the mounting of the position sensors (20,22,24) are outside the stator (14), the mounting process is simple and less time consuming. Therefore, the starter generator (10) as disclosed herein is economic to manufacture.

List of Reference Numerals

Sr. No. Description
10 Starter generator
12 Rotor
14 Stator
16 Base plate
18 Boss
20, 22, 24 Set of position sensors
26 Outer surface
28 Side wall
30 Plurality of sensing elements
32 Opening

34 Top surface
36 Protrusion
38 Plurality of magnets
Equivalents:

With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/ plural permutations may be expressly set forth herein for sake of clarity.
It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as "open" terms (e.g., the term "having" should be interpreted as "having at least," etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an" (e.g., "a" and/or "an" should typically be interpreted to mean "at least one" or "one or more"); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of "two recitations," without other modifiers, typically means at least two recitations, or two or more recitations). It will be further understood by

those within the art that virtually any disjunctive word and/ or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase "A or B" will be understood to include the possibilities of "A" or "B" or "A and B."
While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.

We claim
1. A starter generator (10) for vehicle, the starter generator (10)
comprising:
a base plate (16);
a rotor (12) movably attached to the base plate (16), the rotor (12) comprising
a side wall (28);
a cavity to accommodate a stator (14) therein, the cavity is encapsulated by the side wall (28);
a plurality of sensing elements (30) disposed at an outer surface (26) of the said side wall (28);
a set of position sensors (20, 22, 24) rigidly mounted on the base plate (16), wherein the set of position sensors (20, 22, 24) is placed outside periphery of the rotor (12) to sense the sensing elements (30).
2. The starter generator (10) as claimed in claim 1, wherein at least one of the position sensors (20, 22, 24) is a hall sensor.
3. The starter generator (10) as claimed in claim 1, wherein the set of position sensors (20, 22, 24) is placed one after another at a gap of 120 degrees electric angle between two consecutive sensors (20, 22, 24).
4. The starter generator (10) as claimed in claim 1, wherein at least one of the position sensors (20, 22, 24) is cuboidal in shape.

5. The starter generator (10) as claimed in claim 1, wherein at least one of the position sensors (20, 22, 24) is mounted such that the longitudinal length of the position sensors (20, 22, 24) is oriented orthogonal to a planar surface of the base plate (16).
6. The starter generator (10) as claimed in claim 1, wherein the set of position sensors (20, 22, 24) is electronically connected to Electronic Control Unit (ECU) of the vehicle.
7. The starter generator (10) as claimed in claim 1, wherein a plurality of magnets (38) is mounted on an inner surface of the side wall (28) of the rotor (12), the plurality of magnets (38) positioned consecutively with alternate north and south pole configuration.
8. The starter generator (10) as claimed in claim 1 and 7, wherein the plurality of sensing elements (30) is positioned corresponding to either north poles of the plurality of magnets (38) or south poles of the plurality of magnets (38).
9. The starter generator (10) as claimed in claim 1, wherein the base plate (16) includes a protrusion (36) configured for mounting of the stator (14).